description
stringlengths 2.98k
3.35M
| abstract
stringlengths 94
10.6k
| cpc
int64 0
8
|
|---|---|---|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. provisional patent application No. 62/361,309, entitled “Method for Making Insulated Door Panels Using Separate Façade Surfaces”, filed on Jul. 12, 2016, which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] This disclosure relates to manufacturing garage door panels, in particular, to manufacturing insulated garage door panels.
BACKGROUND
[0003] Exterior cosmetic design of door panels, such as those for garage doors, is often integrated with the door panels. For example, an exterior cosmetic design is often stamped onto the structural component, such as a “U” shaped steel sheet to form an exterior structure of a door panel. The exterior structure may then be married with an interior structure with expanded foam or other insulation material filled in between the exterior structure and the interior structure to form an insulated garage door panel. The tooling cost is often substantial as a result of the complicated shape of the exterior structure that includes both a design pattern and different structural elements and is thus a disincentive for providing various trendy designs.
SUMMARY
[0004] This disclosure describes assemblies and methods for making insulated door panels using separate façade surfaces, in order to separate the manufacturing process of the exterior cosmetic design surface from the structural components of the door panels. This allows for a same production line for the door panels to accept façade surfaces of different designs and to produce door panels of these different designs and lowering the overall tooling costs for the different designs.
[0005] The facade surfaces are made in separate production lines using various techniques, including casting, molding, vacuum forming, extrusion, and the like. A particular production technique may be selected based on the desired material, cost consideration, or both. The façade surfaces are then fed into door panel production lines that fill polyurethane foams to form complete insulated garage door panels.
[0006] There are several advantages using such offline façade surfaces to make door panels. First, different door panel façade designs can be created on demand without altering the door panel production lines. Second, compared to previous manufacturing methods, a wider selection of materials and costs of the façade surfaces becomes available to the market using this method. Third, using this manufacturing method, different lamination structures (e.g., steel to foam, urethane to foam, fiberglass to foam, or wood to foam, among others) can be selected to cope with geographical requirements in terms of wind, rain, temperature variation, humidity, etc. Last but not least, the raw material for making the separated façade surface can be substantially two dimensional (such as a steel or plastic sheet) and the tooling cost for creating new and different designs on the two-dimensional raw material is significantly lowered due to the offline façade surface production.
[0007] In a first general aspect, a method for making an insulated door panel includes providing a façade surface having a design pattern. The design pattern is surrounded by a planar frontal surface near edges of the façade surface. A backing bracket is provided to receive the façade surface. The backing bracket includes a top wall, a bottom wall, and a pair of side walls to form an interior area. The façade member is aligned with the backing bracket such that a rear surface of the façade member contacts the backing bracket top wall. The façade surface is adhered to the backing bracket directly or via an expandable medium.
[0008] In some embodiments, providing the façade surface includes providing a design member onto the façade member front surface. For example, the design member may be stamped or roll-formed onto the façade member.
[0009] In some other embodiments, providing the façade surface includes stamping or roll-forming the design pattern in the originally flat piece of material to form the façade surface. For example, the originally flat piece of material is a metal sheet, such as steel.
[0010] In yet some other embodiments, providing the façade surface includes heat-forming at least one of the design pattern in the originally flat piece of material to form the façade surface. For example, the originally flat piece of material is a polymer based plastic sheet.
[0011] In some embodiments, providing the backing bracket includes providing a metal sheet and forming the metal sheet in a tool into a pan shape having a cross section of at least four folded corners. The receiving planar frontal surface if formed at an edge of the metal sheet. For example, the metal sheet can be made of steel. In some specific examples, forming the metal sheet in a tool further includes forming a groove and a tongue, wherein the groove is in between a first and a second folded corners and the tongue is in between a third and a fourth folded corners. The groove and tongue have matching outer profiles such that when the garage door is at a closed position, the groove and tongue form a barrier against rain, wind, and dust.
[0012] In yet some other embodiments, producing the planar frontal surface near edges of the façade surface includes molding a compliant material to form the planar frontal surface along with the design pattern on the façade surface. For example, the compliant material can be a curable composite that is one of urethane, a mixture of epoxy and fiberglass, and a mixture of resin and filler material.
[0013] In some embodiments, an overlay surface is adhered on top of the façade surface, wherein the overlay surface includes natural wood.
[0014] In a second general aspect, a garage door panel assembly includes a façade surface having a planar frontal surface near edges of the façade surface. A three dimensional design pattern is within the planar frontal surface. A backing bracket has a receiving planar frontal surface that is mate-able with the planar frontal surface near edges of the façade surface. The backing bracket is assembled to the façade surface. An adhesive holds the façade surface to the backing bracket.
[0015] In some embodiments, the façade surface further includes a convex guide next to the planar frontal surface. The convex guide abuts the edges of the façade surface.
[0016] In some other embodiments, the convex guide abuts a transitional planar frontal surface meeting the edges of the façade surface.
[0017] In yet some other embodiments, the backing bracket further includes a concave guide for receiving the convex guide.
[0018] In some embodiments, the backing bracket comprises at least four substantial right-angle folds.
[0019] In some other embodiments, the receiving planar frontal surface is between an edge of the backing bracket and one of the at least four substantial right-angle folds that is closest to the edge.
[0020] In yet some other embodiments, the backing bracket further comprises a groove and a tongue, the groove and the tongue having a substantially similar shape such that the tongue can fit into the groove conformingly.
[0021] In some embodiments, the façade surface is a piece of metal, a piece of urethane, a piece of composite including fiberglass and resin, or a piece of plastic.
[0022] In some other embodiments, the adhesive is expandable foam filled in between the façade surface and the backing bracket.
[0023] In a third general aspect, a garage door panel assembly includes a stainless steel backing bracket bent to form at least four bends and having a receiving planar frontal surface between an edge of the stainless steel backing bracket and one of the at least four bends closest to the edge. A flat plywood layer is mated onto the receiving planar frontal surface and aligned with the stainless steel backing bracket. A filler material fills in between the flat plywood layer and the stainless steel backing bracket for insulation and adhering the flat plywood layer to the stainless steel backing bracket. An outer layer is adhered onto the flat plywood layer, the outer layer made of real wood and shaped with decorative designs.
DESCRIPTION OF THE FIGURES
[0024] FIG. 1A is an illustration of an assembly and method for producing an insulated garage door panel using a separate piece of façade surface.
[0025] FIG. 1B illustrates a cross sectional side view of the assembly of FIG. 1A .
[0026] FIG. 2A is a first embodiment of an assembled insulated garage door panel of FIGS. 1A and 1B .
[0027] FIG. 2B is a second embodiment of an assembled insulated garage door panel of FIGS. 1A and 1B .
[0028] FIG. 3A is a high-speed embodiment of an assembly of a steel façade surface and an backing bracket.
[0029] FIG. 3B is a high speed embodiment of an assembly of a urethane or fiberglass façade surface and the backing bracket of FIG. 3A .
[0030] FIG. 4A is another high-speed embodiment of an assembly of a steel façade surface and an backing bracket.
[0031] FIG. 4B is another high-speed embodiment of an assembly of a urethane or fiberglass façade surface and the backing bracket of FIG. 4A .
[0032] FIG. 5A is yet another high-speed embodiment of an assembly of a steel façade surface and an backing bracket.
[0033] FIG. 5B is another high-speed embodiment of an assembly of a urethane or fiberglass façade surface and the backing bracket of FIG. 5A .
[0034] FIG. 6A illustrates a front view of several garage door panels made using the assembly of separate façade surfaces.
[0035] FIG. 6B illustrates a detailed view of an example of the façade surface of FIG. 6A .
[0036] Like elements are labeled using liked reference numerals.
DETAILED DESCRIPTION
[0037] FIGS. 1A and 1B are illustrations of an insulated garage door panel assembly 100 in which a separate façade member 110 is employed to advantage. In the embodiment illustrated in FIGS. 1A and 1B , the garage door panel assembly 100 includes the façade member 110 , a backing bracket 120 , and a filler 130 deposited between the façade member 110 and the backing bracket 120 to act as an insulator and in some embodiments, an adhesive, to at least partially secure the façade member 110 to the bracket 120 .
[0038] In the embodiment illustrated in FIG. 1B , the backing bracket 120 includes a top wall 120 a, a bottom wall 120 b and a pair of sidewalls 120 c and 120 d formed from four substantial right-angle folds 142 , 144 , 146 and 148 to enclose an interior area 133 . In the embodiment illustrated in FIGS. 1A and 1B , the top wall 120 a includes an opening 131 , which enables access to the interior area 133 when filling the interior area 133 with the filler 130 . When assembled, the top wall 120 a, provides support to and enables attachment of the of the façade member 110 to the backing bracket 120 . In particular and specifically referring to FIG. 1B , the top wall 120 a of the backing bracket 120 is sized and otherwise configured to receive and/or mate with the façade member 110 near and/or otherwise adjacent to edges 111 of the façade member 110 . As illustrated in FIG. 1B , for example, when the façade member 110 is secured to the backing bracket 120 , the edges 111 of the façade member 110 generally align with the folds 142 and 148 ; however, it should be understood that the size of the façade member 110 may vary such that the edges 111 may not extend and to and otherwise align with the folds 142 and 148 .
[0039] According to some embodiments, the backing bracket 120 includes a tongue 122 and a groove 124 formed in respective sidewalls 120 c and 120 d. The tongue 122 and the groove 124 have complementary shapes such that a tongue 122 in a first panel assembly 100 fits within the groove 124 of a second and adjacent panel assembly 100 , as best illustrated, for example, in FIGS. 2A and 2B , when multiple panel assemblies 100 are secured together. When securing adjacently positioned panel assemblies 100 together, traditional panel hinges (not illustrated) are secured to the bottom wall 120 b of the backing bracket 120 for pivotably connecting adjacently positioned door panel assemblies 100 . According to some embodiments, the backing bracket 120 may have different thicknesses 130 and lengths 132 to accommodate different product lines.
[0040] According to some embodiments, the backing bracket 120 is formed by a separate stand-alone manufacturing process, such as, for example, roll forming, stamping, or other suitable methods. For example, according to one particular embodiment, the backing bracket 120 is produced using steel sheets that are roll-formed into a desired cross-sectional shape.
[0041] In the embodiment illustrated in FIGS. 1A and 1B , the façade member 110 includes a front surface 114 and a rear surface 115 . According to some embodiments, all or a portion of the front surface 114 and/or the rear surface 115 includes a three-dimensional design or pattern 112 extending therefrom. In other embodiments, the front surface 114 and/or the rear surface 115 can be formed without any design or pattern 112 extending therefrom, can include indentations, print, can optionally can be curved, stepped or any other configuration and/or can include any combination of these particular configurations. In other embodiments, an additional overlay layer can be secured onto the front surface 114 , such as, securing a natural wood overlay onto the front surface 114 . According to some embodiments, the façade member 110 is formed by a separate manufacturing process, such as stamping from sheet metal, molding (such as vacuum forming or otherwise) from sheet plastic or composite materials (such as urethane, resin, epoxy and fiberglass).
[0042] During assembly, the backing bracket 120 and the façade member 110 are aligned and assembled by confining their bodies using a plurality of rollers, such as a pair of side rollers 150 a and 150 b, a bottom roller 152 , and a top roller 154 , as best illustrated in FIG. 1A . Although only four rollers 150 a, 150 b, 152 and 154 are illustrated, any number of rollers can be used to confine, position and/or otherwise resist relative movement of the façade member 110 and the backing bracket 120 , especially when the foam 130 is deposited within the interior area 133 and expands during curing. In operation, the top roller 154 and the bottom roller 152 (or additional rollers, as needed, including downstream of the assembly line) may be used to exert a force to push or otherwise sandwich the façade member 110 and the backing bracket 120 together. It should be understood that although the bottom roller 152 and the top roller 154 are illustrated as cylindrical bodies, in some embodiments, the rollers may include two or more wheels spaced or otherwise positioned across the width of the façade member 110 or the backing bracket 120 in order to avoid contact with and potentially damaging the design pattern 112 .
[0043] In addition, the side rollers 150 a and 150 b provide side/lateral support for the side walls 120 c and 120 d of the backing bracket 120 such that the side walls 120 c and 120 d resist and otherwise prevent deformation outwards (i.e., away from the interior area 133 ) under any internal pressure generated by the expandable foam 130 . According to some embodiments, the side rollers 150 a and 150 b also function to align the façade member 110 with the backing bracket 120 such that the frontal surface 114 is aligned with the top wall 120 a. Although rollers 150 , 152 , and 154 are illustrated to assemble the façade member 110 to the backing bracket 120 , it should be understood that other methods may also be used to guide and assemble the façade surface 110 to the backing bracket 120 . According to embodiments disclosed herein, the illustrated assembly method enables rapid assembly of the same backing bracket 120 to façade members 110 having different designs 112 .
[0044] According to various embodiments disclosed herein, the configurations of the façade members 110 and the backing bracket 120 , and in particular, the top wall 120 a, may vary. For example, in the embodiment illustrated in FIG. 2B , the top wall 120 a is formed having an upturned end portion 210 to increase the strength of the top wall 120 a and thus, resistance to overall bending.
[0045] In some embodiments, the filler 130 is an expandable foam disposed inside the interior area 133 that functions as both an insulator and an adhesive. Thus the expandable foam 130 holds the façade surface 110 to the backing bracket 120 and fills any empty space within the interior area 133 . In addition to the expandable foam functioning as an adhesive, it should be understood that other method of securing the façade member 110 to the backing bracket are available, such as, for example, the use of an adhesive provided on the top wall 120 b of the backing bracket 120 or by use of bolts or any other type of securing or clamping mechanism.
[0046] FIG. 3A is another embodiment illustrating a door panel assembly 310 having a façade member 312 attachable to a backing bracket 120 . In FIG. 3A , the façade member 312 includes a self-aligning guide structure 314 extending from the edge 111 of the façade member 110 for mating with a corresponding receptacle 324 on the top wall 120 a of the backing bracket 120 to facilitate high speed assembly. In operation, the self-aligning guide structure 314 is formed of a curvilinear structure extending from the edge 111 of the façade member 314 and is shaped such that as the façade member 314 is positioned adjacent to the backing bracket 120 , the self-aligning structure 314 self-aligns and nests within the corresponding receptacle 324 to align the façade member 314 with the backing bracket 120 . As illustrated in FIG. 3A , As illustrated, the self-aligning structure 314 is formed of a convex shape and is sized to nest within the concave receptacle 324 . Such contoured coupling between the convex and concave guides 314 and 324 enables a much faster assembly speed than using the planar frontal surface 114 alone, even if the rollers 150 provides a certain amount of alignment. For example, the convex and concave guides 314 and 324 allow for a production speed of about 100 feet per minute, while using the planar frontal surfaces 114 and 120 a can only allow for a production speed of about 9 feet per minute. This difference is a result of the alignment efficiency and accuracy that the convex/concave coupling contours provide. After production, such concave and convex contours may further reinforce the bending rigidity, and/or improve the overall structural integrity by enabling the façade member 312 to limit the bending movement of the tongue 122 and the groove 124 . According to some embodiments, the façade member 312 is preferably formed of steel; however, it should be understood that other materials may be used for form the façade member 312 .
[0047] FIG. 3B is a high speed embodiment of an assembly 320 of a urethane or fiberglass and the interior structure of FIG. 3A . The assembly 320 uses the same configuration for the backing bracket 120 and replaces the stainless steel façade surface 312 with a molded façade surface 332 . The molded façade member 332 may be made from urethane, fiberglass, plastic, or other moldable materials. The façade member 332 is formed having a concave slot 333 on the planar rear surface 115 thereof. The concave slot 333 may avoid any substantial thick portion in the façade surface 332 in order to prevent molding shrinkage or other potential manufacturing defects.
[0048] In the embodiment illustrated in FIG. 3B , the concave slot 333 receives a tubular or cylindrical guide 334 , which is sized to align the façade member 332 to the backing bracket 120 , as similarly described above. According to some embodiments, the tubular or cylindrical guide 334 is made of a different material than the façade member 332 . For example, the façade member 332 may be made from a mixture of resin and fiberglass and the tubular or cylindrical guide 334 may be made of extruded plastic or rubber. However, it should be understood that the façade member 332 and the guide 334 may be integrally formed (i.e., a single unitary piece) of the same material. Compared to the assembly 310 of FIG. 3A , the assembly 320 enjoys similar production speeds. In addition, the different geometries can be selected based on different design patterns. For example, some design patterns are more suitably formed using stamping while other design patters are more suitably formed by molding.
[0049] FIG. 4A is another high-speed embodiment of an assembly 410 in which a façade member 412 is employed to advantage. Similar to the façade member 312 , the façade member 412 includes convex guides 414 extending from an edge of the façade member 412 for alignment during high speed production. Correspondingly, the backing bracket 120 includes corresponding concave guides 424 to receive the convex guides 414 therein. As illustrated, the convex guides 414 are formed having a triangular cross section having an apex 416 ; however, it should be understood that other cross-sectional shapes may be utilized. Regardless of the cross-sectional shape of the guides 414 , the corresponding guide 424 is formed of a complementary shape to receive the guide 414 therein. According to preferred embodiments, the façade member 412 is formed of a steel material, however, it should be understood that other materials may be utilized.
[0050] FIG. 4B is another high-speed embodiment of an assembly 420 in which a urethane or fiberglass façade surface 432 is employed to advantage. As illustrated, the façade member 432 is formed having integral convex guide 434 for insertion within a corresponding concave guide 424 of the backing bracket 120 . In some embodiments, additional structures may be provided to increase the bending stiffness of the façade surface 432 , such as additional extrusions or ribs 436 .
[0051] FIG. 5A is yet another high-speed embodiment of a door panel assembly 510 in which a steel façade member 512 is employed to advantage. In the embodiment illustrated in FIG. 5A , the façade member 512 includes an upturned portion 514 formed having a first leg 516 extending from a rear surface 115 , a second leg 518 extending generally perpendicularly from the first leg 516 and a third leg 520 , extending generally perpendicular to the second leg 518 and generally parallel to the first leg 516 . As illustrated, the upturned portion 514 , and in particular, the third leg 520 , serves as a ledge or surface to receive and otherwise engage portions of the backing bracket 520 , and in particular, a fold 511 at the edge of the. Such configuration enables high speed assembly without substantially altering the backing bracket 120 of FIGS. 1A and 1B . The backing bracket 120 may further include a fold or otherwise upturned end 522 formed on the top wall 120 a. In use, the fold 522 provides a rounded contact surface for contacting and otherwise engaging the third leg 520 . The assembly 510 enables similar high speed production as the assembly 310 and 410 .
[0052] FIG. 5B is another high-speed embodiment of an assembly 520 in which a urethane or fiberglass façade member 532 is employed to advantage. In the embodiment illustrated in FIG. 5B , the façade member 532 includes at least one guide member 536 extending from the rear surface 115 of the façade member 532 for alignment with the upturned ends 522 of the backing bracket 120 .
[0053] FIG. 6A illustrates a front, external view of a garage door 600 made using the assembly of separate façade members 610 . FIG. 6B illustrates a detailed cross sectional view of the façade member 612 of FIG. 6A . In this example, the façade surfaces 610 are made by stamping on metal sheets to produce design pattern 612 . The design pattern 612 includes a deep draw portion 616 and a transitional portion 618 . The total width 615 of the design pattern 612 is less than the width of the façade member 610 . During installation, the façade member 612 is coupleable to a backing bracket 120 , as described above. Alternatively, the frontal surface 114 may be modified into one of the examples illustrated in FIGS. 3A, 4A, and 5A .
[0054] In the foregoing description of certain embodiments, specific terminology has been resorted to for the sake of clarity. However, the disclosure is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes other technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as “left” and right”, “front” and “rear”, “above” and “below” and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms.
[0055] In this specification, the word “comprising” is to be understood in its “open” sense, that is, in the sense of “including”, and thus not limited to its “closed” sense, that is the sense of “consisting only of”. A corresponding meaning is to be attributed to the corresponding words “comprise”, “comprised” and “comprises” where they appear.
[0056] In addition, the foregoing describes some embodiments of the disclosure, and alterations, modifications, additions and/or changes can be made thereto without departing from the scope and spirit of the disclosed embodiments, the embodiments being illustrative and not restrictive.
[0057] Furthermore, the disclosure is not to be limited to the illustrated implementations, but to the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the disclosure. Also, the various embodiments described above may be implemented in conjunction with other embodiments, e.g., aspects of one embodiment may be combined with aspects of another embodiment to realize yet other embodiments. Further, each independent feature or component of any given assembly may constitute an additional embodiment.
|
This disclosure describes methods for making insulated door panels using separate façade members, in order to separate the manufacturing process of the exterior cosmetic design surface from the structural components of the door panels. This allows a same manufacturing line for the door panels to accept façade members of different designs and to produce door panels of these different designs. The facade members are made in separate production lines using various techniques, including casting, molding, vacuum forming, extrusion, and the like. The façade members are then fed into door panel production lines that fill polyurethane foams to form complete panels. The façade members become the exterior skins of the panels with minimum overlay with any backing structure to reduce material wastes, as well as lowering tooling costs for different designs due to the common backing structure that may be shared.
| 4
|
FIELD OF THE INVENTION
[0001] The present invention relates to a composition for improving brain function and a method for improving brain function.
BACKGROUND OF THE INVENTION
[0002] The symptoms and diseases caused by a deterioration of brain function include depression, schizophrenia, delirium, dementia (cerebrovascular dementia, Alzheimer's disease, and the like), and the like. With the aging of the population in modern society, especially the increase in the number of people with dementia is becoming a serious social issue. There are various symptoms observed among individuals with dementia, and symptoms commonly observed among them include dysmnesia, disorientation, decline in judgment and thinking ability, and the like. The forms of dementia which affect especially a large number of individuals are cerebrovascular dementia and Alzheimer's disease. For example, in patients with cerebrovascular dementia, damage to the nerve cells in the cerebral cortex and hippocampus caused by obstruction of the brain blood flow gives a rise to cognitive impairment and dysmnesia. For this reason, in addition to treating pre-existing diseases, such as high-blood pressure, diabetes, and hypercholesterolemia, which may trigger cerebrovascular disorders, drugs which are capable of improving brain blood flow and/or drugs which are capable of protecting brain nerve cells are administered. In the meantime, causes of Alzheimer's disease have not been clearly elucidated; however, since a decrease in the level of acetylcholine, which is a neurotransmitter in the brain, is observed in the patients with this disease, a hypofunction of cholinergic neurons is assumed to be one of the causes (reference 2). Therefore, a therapeutic strategy aiming at preventing the hypofunction of cholinergic neurons by increasing the concentration of acetylcholine has been the mainstream for the treatment of Alzheimer's disease.
[0003] Currently, as a therapeutic drug against Alzheimer's disease, acetylcholinesterase inhibitors, for example, such as donepezil hydrochloride, are commercially available. However, the acetylcholinesterase inhibitors, such as donepezil hydrochloride, have their drawbacks that they should not be administered for an extended period of time due to their hepatotoxicity and strong side-effects as well as that they are costly.
[0004] Meantime, as a report in regard to peptides showing an anti-amnesic effect, for example, it has been reported that XPLPR (X represents L, I, M, F, or W) (SEQ ID NO:1) demonstrated an improving effect against scopolamine-induced amnesia when administered intracerebroventricularly or orally at 300 mg/kg, and, a release of acetylcholine from the intracerebral C3a receptor has been suggested as one of the mechanisms involved in this effect (reference 1). However, all these peptides need to be administered in a large dose orally, intraabdominally, intracerebroventricularly, or the like in order to demonstrate their actions; therefore, they are not considered to be orally ingestible substances capable of demonstrating a sufficient level of effects. In addition, there has been no report on evaluation of peptides of the present invention and their analogs; therefore, their actions involved in the improvement of brain function have been hitherto unknown.
[0005] Thus, with the progress of the aging of the society, demands for development of pharmaceutical agents, which prevent the symptoms and diseases caused by a deterioration of brain function and further demonstrate curative effects on the symptoms and diseases, and for further development of safer compounds which are excellent in food application are becoming increasingly stronger.
[0006] Scopolamine is believed to function as a muscarinic receptor antagonist that induces the hypofunction of cholinergic neurons. Working as an inducer of brain dysfunction, scopolamine is used in the production of model animals to be used in the development of therapeutic drugs against Alzheimer's disease. In regard to the prophylactic and/or curative activities against brain dysfunction by the action of scopolamine, their effects may be demonstrated in behavioral pharmacological tests, such as a Y-shaped maze test, an eight-arm maze test, and a passive avoidance test. Further, the effects of improving and/or strengthening brain function may be demonstrated in the same behavioral pharmacological tests with use of normal animals.
[0007] Regarding the function of Phe-Pro a hypotensive lowering activity based on ACE inhibitory activity has been reported (reference 3). However no reports evaluated activities of the peptide Phe-Pro in improving brain functions and such activities of these peptides can not be expected.
SUMMARY OF THE INVENTION
[0008] The present invention provides a composition which may be ingested orally in a small dose for the purpose of improving brain function. Further, the present invention provides a method for improving brain function. Several aspects of the present invention are as follows.
[0009] (1) The present invention is a composition for improving brain function, comprising, as an active ingredient, Phe-Pro or a salt thereof.
[0010] (2) The present invention is also the composition according to (1), which is for oral ingestion.
[0011] (3) The present invention is also a method for improving brain function, the method including administering to a non-human animal Phe-Pro or a salt thereof.
[0012] (4) The present invention is also the method according to (3), in which the administering is oral administration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 shows a prophylactic effect of a peptide Phe-Pro (FP) against scopolamine-induced amnesia. Water (control), scopolamine alone, or 500 nmol/kg weight or 5000 nmol/kg weight of FP together with scopolamine, was administered to mice, and their respective prophylactic effects against amnesia were evaluated in accordance with a method described in Example 1. The vertical axis in FIG. 1 shows the percentage of spontaneous alternation behavior. In order to confirm whether or not amnesia was induced, a significant difference between a water-administered control group and a scopolamine control group to which scopolamine was administered alone was calculated using Student's t-test. ** indicates P<0.01 with respect to the water-administered control group. A significant difference between the FP-administered group and the scopolamine control group was calculated using Student's t-test. # indicates P<0.05 with respect to the scopolamine control group.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] The peptide Phe-Pro in the composition of the present invention includes may be chemically-synthesized peptide or a peptide derived from a natural product. For the chemical synthesis of these peptides, a commonly-used method, such as a solid phase synthesis (t-Boc-chemistry or Fmoc-chemistry) and a liquid phase synthesis, may be employed. For example, these peptides may be synthesized using an automated peptide synthesizer, such as the peptide synthesizer (PSSM-8) available from Shimadzu. A method for the peptide synthesis, appropriate reaction conditions, and the like may be selected based on the common general technical knowledge of a person skilled in the art at the discretion of the person. A method for purifying a chemically-synthesized peptide is also well known to those in the art.
[0015] As used in the specification, when referring to the peptide Phe-Pro, “Phe-Pro” and “the peptide Phe-Pro” include salts thereof unless otherwise clearly indicated or otherwise obvious within the context that they should be excluded. Examples of such salts include salts, such as sodium salts, potassium salts, and hydrochloride salts, which may exist under physiological conditions. Meanwhile, the composition of the present invention may include other peptide and a free amino acid or a salt thereof, in addition to the peptide Phe-Pro, which is the active ingredient of the composition of the present invention. In relation to the present invention, three-letter codes, single-letter codes, and peptide notation follow the general rules well known to those in the art.
[0016] The effect in improving brain function of the composition of the present invention or the peptide Phe-Pro may be confirmed using a system based on an evaluation system for therapeutic drugs against Alzheimer's disease, the system using a Y-shaped maze test, for example. Specifically, a muscarinic receptor antagonist, such as scopolamine, may be used on a rat or a mouse so as to cause a hypofunction of the cholinergic neurons. Then, either the rat or the mouse may be administered with a drug which induces amnesia by causing brain dysfunction alone or together with the composition of the present invention or the peptide Phe-Pro, or alternately the rat or the mouse may be administered, prior to the administration of such a drug, with the composition of the present invention or the peptide Phe-Pro. Then, the mouse or the rat may be subjected to a test using a Y-shaped maze so that the prophylactic actions against amnesia of the composition of the present invention may be confirmed by using the percentage of change in spontaneous alternation behavior to different arms and the total number of entries into the maze as indicators.
[0017] In the tests, the negative control may be, for example, an animal received only water. In an experiment to confirm the prophylactic action against drug-induced amnesia of the peptide Phe-Pro, an animal administered only with a drug, which induces amnesia by causing brain dysfunction, such as scopolamine, may be included to be used as a control.
[0018] The composition of the present invention includes, as an active ingredient, the peptide Phe-Pro and oral administration or oral ingestion thereof allows achievement of the desired effects described above. The period of administration or ingestion of the composition of the present invention may be variously adjusted upon consideration of the age of a target of the administration or ingestion, such as a human or non-human animal, and the health conditions and the like of the target. Examples of the non-human animal include non-human higher vertebrate animals, particularly non-human animals, including pet animals, such as dogs and cats, and domestic animals, such as cattle, horses, pigs, and sheep; however, the non-human animal is not limited thereto. A single administration of the composition of the present invention is enough to demonstrate its effects; however, a continuous effect may be expected by continuous ingestion, which is once or more a day. The composition of the present invention when used as medicine may be in the form of drugs for oral administration. For example, the form may be a tablet, a pill, a hard capsule, a soft capsule, a microcapsule, a powder, a granule, a liquid, or the like. When produced as medicine, the composition of the present invention may be produced in a unit dose required for commonly-approved drug administration by, for example, including a pharmaceutically approved material, such as a carrier, an excipient, a filler, an antiseptic, a stabilizer, a binder, a pH modifier, a buffer, a thickener, a gellant, a preservative, and an antioxidant, accordingly as needed.
[0019] The composition of the present invention may also be used as a material for food and beverage or a material for animal feed. For example, the composition of the present invention or the peptide Phe-Pro which is the active ingredient of the composition of the present invention, may be considered a functional food, such as a food for specified health use, which is effective in improving brain function.
[0020] The dose of administration or ingestion of the present composition or the peptide Phe-Pro is preferably 0.1 mg/kg weight to 10 mg/kg weight per administration or ingestion in general in order to obtain desired effects, in terms of the amount of the peptide Phe-Pro which is the active ingredient. The dose per ingestion in a food, which is, for example, a functional food, may also be lowered further than the above-described level, depending on the number of ingestions per day. An appropriate dose of ingestion may be further adjusted upon consideration of various factors as described above.
[0021] The nutritional balance, flavors, and the like of a food, such as a functional food, including the composition of the present invention or the peptide Phe-Pro which is the active ingredient of the composition, may be improved by addition of an additive either: made of other ingredient used in food, such as a saccharide, a protein, a lipid, a vitamin, a mineral, and a flavor, which include various carbohydrates, lipids, vitamins, minerals, sweeteners, flavoring agents, coloring agents, texture enhancers, and the like, for example; or made of a mixture thereof. Animal feed containing the composition of the present invention or the peptide Phe-Pro which is the active ingredient of the composition, may be prepared similarly to food for human consumption.
[0022] For example, the above-described functional food may have the form of a solid, a gel, or a liquid, may be in the form of, for example, any one of various processed foods and beverages, dry powder, a tablet, a capsule, a granule, and the like, and, further, may be any of various beverages, yogurt, a liquid food, jelly, a candy, a retort pouch food, a tablet confectionary, a cookie, a sponge cake, bread, a biscuit, a chocolate, and the like.
[0023] When a functional food, such as a food for specified health use, containing the composition of the present invention is manufactured, although depending on how the composition has been added and how the food containing the composition is served as a product, the functional food is prepared so that the amount of the peptide Phe-Pro which is the active ingredient of the composition, to be contained in 100 g of the final product may be 1 μg to 10 g, preferably 10 μg to 1 g, more preferably 100 μg to 100 mg.
[0024] The composition of the present invention or the peptide Phe-Pro which is the active ingredient of the composition, may improve brain function, thereby being capable of preventing amnesia and strengthen memory. Further, the composition of the present invention or any one of the above-described peptides, which is the active ingredient of the composition, may also be used for treatment or prevention of the symptoms and diseases caused by a deterioration of brain function, the symptoms and diseases including depression, schizophrenia, delirium, dementia (cerebrovascular dementia, Alzheimer's disease, and the like), and the like.
[0025] Hereinafter, the present invention will be specifically described by way of Examples; however, the scope of the invention is not limited to Examples.
EXAMPLES
Example 1
Prophylactic Activity of Phe-Pro Against Amnesia
[0026] Male mice (n=15) of the ddY strain (approximately 7-week old) were used, and they took food and water ad lib. Test substances used were 500 mol/kg weight (130 μg/kg weight) or 5000 nmol/kg weight (1300 μg/kg weight) of FP. The test substances were administered to the mice once orally 60 minutes before the execution of a Y-shaped maze test for evaluation of spontaneous alternation behavior. Further, 30 minutes before the execution of the Y-shaped maze test, 1 mg/kg weight of scopolamine was subcutaneously administered on the backs of the mice in order to induce brain dysfunction (dysmnesia and/or cognitive impairment) in the mice. In the Y-shaped maze test, a Y-shaped maze was used as an experimental device, in which the length of each arm was 40 cm, the height of the wall was 12 cm, the width of the floor was 3 cm, and the width of the upper part was 10 cm, and three arms were connected to each other at an angle of 120 degrees. Each of the mice was placed at the tip of any one of the arms of the Y-shaped maze, and then let go to freely explore in the maze for 8 minutes. The sequence of the arms each of the mice entered was recorded. The number of entries by each of the mice for each of the arms during the measurement time was counted to be the total number of entries. In the sequence, the combination in which three different arms were selected in succession (for example, with the three arms respectively called A, B, and C, if the sequence of the arms entered is ABCBACACB, the count is 4 inclusive of overlapping) was investigated, and the number of the count was used as the number of spontaneous alternation behavior. The percentage of spontaneous alternation behavior was calculated by dividing the number of spontaneous alternation behavior by a number obtained by subtracting 2 from the total number of entries, and multiplying a resultant number by 100. The percentage of spontaneous alternation behavior was used as an indicator. A higher value of the indicator suggested better maintenance of short-term memory. The measured values were expressed in the form of mean±standard error for each group. A significant difference between the control group and the scopolamine control group was calculated using Student's t-test. A significant difference between the scopolamine control group and FP-administered group was calculated using Student's t-test. Results are shown in FIG. 1 . It was suggested that Phe-Pro had a prophylactic activity against amnesia when administered at a dose of 5000 nmol/kg weight (1300 μg/kg).
REFERENCES
[0000]
1. Japanese Patent No. 3898389
2. Science, 217, 408-417 (1982)
3. Journal of Dairy Science, 81, 3131-3138 (1998)
|
The present invention provides a composition which may be ingested orally in a small dose for the purpose of improving brain function, and a method for improving brain function. The present invention is a composition for improving brain function, comprising, as an active ingredient, Phe-Pro.
| 0
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of PCT Application No. PCT/IN2011/000401 filed on Jun. 15, 2011, which claims the benefit of Indian Patent Application No. 2099/MUM/2010 filed on Jul. 23, 2010. The entire disclosures of each of the above applications are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to polymerization processes for the manufacture of condensation polymer, yarn and other products.
BACKGROUND OF THE INVENTION
[0003] Traditionally, batch processes have been used for continuous polymerization in the manufacturing of yarn and other products which are costly and time consuming, as well as lack in product uniformity. For example there is viscosity variation from batch to batch and also during polymer extrusion from the reactor into strands, leading to poor spinning, also leading to high pressure rise across the filters in the polymer lines and spinning packs, high spinning breaks per tonne and poor post processing performance (broken filaments on textured bobbins). Some methods do mention use of a continuous process with different variations such as the use of additives with the accompanying polymerization temperature, spin pack pressure, less uniformity and higher filament breakage rate.
[0004] Cationic dyeable polyester (PET) has been conventionally made by introducing (during polymerization) as a comonomer
a) the sodium salt of 5, sulfoisophthalic acid dimethyl ester (abbreviated SIPM)
or
b) in case of PTA process for PET, after transesterification (catalyzed by sodium acetate etc) of SIPM with excess ethylene glycol to the sodium salt of 5, sulfoisophthalic acid diglycolate (abbreviated SIPE or SIPEG)
[0007] JP 2002-284863 suggests that SIPEG (or SIPM) charge may give a gel with high acid groups in PTA slurry and cationic dyeable polyester PTA route is more complex. (DMT or PTA route)
[0008] U.S. Pat. No. 6,707,852 suggests that to provide increased compatibility with the glycol end-group carrying oligomer (such as BHET) in the PTA route, transesterification of SIPM with MEG to SIPEG is carried out in the PTA route.
[0009] Fully or part conversion from SIPM to SIPEG is recommended by some. JP 2002-284863 and EP 1862488 recommend full conversion; U.S. Pat. No. 6,706,852 recommends part conversion to address the issue of solution stability (vs. crystallization-precipitation).
[0010] High concentration of SIPEG in MEG is desired to reduce MEG removal load on the polymerization reactor and to reduce recycle of the excess solvent in the process. U.S. Pat. No. 6,706,852 suggested that fully converted SIPEG solution is not stable at high concentration (40% or higher) at room temperature. Therefore it needs to be prepared (i.e. SIPM to SIPEG conversion) immediately before use in polymerization. Else, either a lower concentration of less than 20% should be employed, or a partial conversion to SIPEG should be adopted.
[0011] Also point of addition of TiO2 and SIPM/SIPEG, due to the anticipated interaction between the two plays an important role in the reaction. Section [0019] of JP 2002-284863 suggests that the SIPEG charge may give gel with high acid groups in slurry, hence better add later in reaction when carboxylic acid concentration has fallen. JP 2002-284863 suggests feeding SIPEG in slurry. Similarly, EP 1862488 talks about various modes, but section [0043], [0048] and [0057] there suggest preference for addition to slurry. However, that does require adjustment of pH of the slurry. JP 2002-284863 and EP1862488 suggest TiO2 addition in slurry immediately after SIPEG. U.S. Pat. No. 6,706,852 also recommend TiO2 addition immediately following SIPEG, but in oligomer from PTA. U.S. Pat. No. 5,559,205 instead recommends TiO2 addition to oligomer, and before SIPEG, to avoid agglomeration of TiO2.
[0012] Also, the MEG to PTA mole ratio is critical for good spinning. of JP 2002-284863 and the EP 1862488 suggest use of MEG not exceeding 1.2 to avoid excess DEG to avoid spinning problems in continuous polymerization.
[0013] JP 2002-284863 and [0051] in EP 1862488 suggest solving the problem of high viscosity/thickening (resulting from aggregation of ionic/charged parts of SIPEG, and deteriorating spinning/giving gelling) with addition of PEG. [0035] of this patent says only 280 deg C. is used. EP1862488 under [0030] also mentions that PEG reduces heat resistance of polyester, and reduces color tone. EP1862488, under [0057] item 5 sets temp not higher than 280 deg C. Also [0010] of EP 1862488, it introduces the additional problem that “dark-color light fastness” becomes unsatisfactory (because PEG introduces somewhat ‘open’ structure in fiber). This EP 1862488 also claims dyeability at low temp/normal pressure, essentially because of the PEG, a well known effect. JP 2002-284863 under [0025] also suggests that PEG introduces undesirable foaming possibility during polymerization.
[0014] Batch processes as disclosed in the U.S. Pat. No. 6,706,852, employ agitated vessel for carrying out polymerization with SIPM/SIPEG. But polyester manufacturing in large continuous plants has largely moved to reducing/eliminating moving parts (such as agitators) in reactors, particularly the esterifier and prepolymerizer, in an effort to reduce process costs (CAPEX and OPEX). U.S. Pat. No. 5,559,205 suggests additive addition is generally carried out in ‘oligomer line’ leading from esterifier to prepolymerizer U.S. Pat. No. 5,559,205 mentioned need for TiO2 to be well-mixed in oligomer without mentioning how to achieve this as they only ‘metered-in’ the slurry, perhaps with some static mixers, but the later addition of SIPEG simply by ‘metering-in’ into the oligomer line. No mention of need for particularly good dispersion of TiO2 in the TiO2-MEG slurry itself prior to addition to the PTA-MEG slurry.
[0015] Also in U.S. Pat. No. 670,852 and U.S. Pat. No. 6,075,115, it is common knowledge to use phosphoric acid or another phosphorus compound in process using SIPEG is to control the polymer discoloration, particularly when using Ti catalyst as it slows down the catalytic activity of Ti. It teaches that sometimes H 3 PO 4 is not effective and other polymers may perform better. In another application JP 2001-086169 of Kanebo Synthetic Fibers Ltd, discloses a method for producing atmospheric cationic dyable polyester. It suggests an improvement over existing methods but has many drawbacks such as the spinning operatibility is remarkably bad, light fastness is inferior and the degree of polymerization is low.
[0016] JP58-45971B and JP62-89725 disclose batch polymerization methods. If a batch type manufacturing method is used it will extrude by aging of polymer extrusion, will extrude with the polymer viscosity at the time of a start and a difference will arise in the polymer viscosity at the time of the end. When the number of batches increased, there was a problem that the foreign matter in which residual polymer in an iron pot deteriorated mixed or the polymer property difference between the batches became large. Hence the problem of productive efficiency remains with batch processes.
[0017] JP62-146921A suggests a method of extracting oligomer after the end of esterification, leading to another polymerization tank, using continuous polymerization method directly as the above-mentioned measure and manufacturing by the batch type polymerizing method. Since the polymerization reaction serves as a batch method, there are spots of polymer physical properties and there is also a problem that equipment becomes complicated. It also suggests use of additive like PEG which limits polymerization temperature to 285 deg C. Similarly [0030] of EP 1862488 suggests that PEG reduces heat resistance and color tone of polyester and EG:PTA mole ratio of 1.1-1.2. This gives remarkably bad spinning operatibility. [0058] of EP1862488 suggests need of light resistant and heat resistant agents. Also spinning breakage rate is remarkably higher in this art.
[0018] U.S. Pat. No. 5,559,205 discloses a process for adding fully esterifted bis(2-hydroxyethyl) sodium 5 sulfoisophthalate (Na-SIPEG) or bis(2-hydroxyethyl) lithium 5-sulfoisophthalate (Li-SIPEG) to the monomer line of DMT process, or oligomer line or the second esterifier of TPA process to make cationic dyeable polyesters. This patent does not allow addition of TiO 2 in slurry and do not specify need of addition of SIPEG into oligomer. SIPEG is added after TiO 2 addition. Also no reference is made about “continuous process” thus limiting the performance.
[0019] U.S. Pat. No. 6,075,115 discloses a process for making Na-SIPEG solution and Li-SIPEG solution from sodium 5-sulfoisophthalic acid (Na-SIPA) and lithium 5-sulfoisophthalic acid (Li-SIPA) powder. In order to fully esterify Na-SIPA and Li-SIPA, a special titanium catalyst 65 is used, which comprises (1) a titanium compound, a solubility promoter, a phosphorus source, and optionally a solvent or (2) a titanium compound, a complexing agent, a phosphorus source and optionally a solvent, a sulfonic acid. The fully esterified Na-SIPEG and Li-SIPEG solutions were manufactured by a vendor and then shipped to polyester producers. The solution was then injected into the monomer line of DMT process or oligomer line or the second esterifier of TPA process or the second or third vessel of batch polymerization process to make copolyesters. A metal salt of 5-sulfoisophthalic acid fully esterified with methanol is also commercially available. This process makes no mention of continuous process or injection into oligomer line. Also batch process is employed here and TiO 2 is not added in slurry. Also problems of spinning are evident. Hence there is long standing need for faster continuous method of polymerization.
[0020] Patent No. U.S. Pat. No. 7,087,706 and U.S. Pat. No. 4,110,316 suggest use of static mixers in the transfer line for mixing of additives while agitated mixing equipments are generally avoided in order to eliminate chance of process disturbances. However, the chances of gel formation are higher in such vessels. This problem is not addressed by existing methods.
STATEMENT OF THE INVENTION
[0021] A continuous polymerization process wherein a plurality of stirred vessels(intermittent reactor vessels) are employed in oligomer transfer line and least one additive is charged in slurry or solution or as reacted with at least one of the monomers through the stirred vessel. Addition of further additive depends on the kind of reaction and final product.
[0022] The polymerization temperature is 285 deg C. or above. The stirring speed inside the vessel is about 400 to 1000 rpm. The yarn obtained from this process has higher uniformity and filament breakage rate during melt spinning is considerably reduced.
SUMMARY OF THE INVENTION
[0023] In accordance with the present invention there is provided a continuous polymerization process for manufacturing a condensation polymer; said process comprising the following steps:
a. employing an assembly comprising at least one initial reactor vessel, at least one final reactor vessel and optionally at least one intermittent reactor vessel; b. connecting said reactor vessels to each other through one or more transfer lines for leading the reactive materials from one vessel to another; c. adding the reactant components to at least one of the initial reactor vessels; d. optionally adding additives to any of said reactor vessels or in the transfer lines; e. stirring the reactive materials relatively vigorously in the intermittent reactor vessel after the addition of the additives; f. optionally stirring the reactive materials relatively mildly in the initial reactor vessel; g. obtaining intermediates from at least one of the intermittent reactor vessel; and h. obtaining reaction products from the final reactor vessel.
[0032] Typically, the polymerization is carried out at a temperature not lower than 285 deg C.
[0033] Typically, the step of vigorous stirring is carried out at a speed of about 400 to about 1000 rpm.
[0034] Typically, the step of vigorous stirring is carried out for a period less than 10 minutes, preferably less than 5 minutes.
[0035] Typically, the step of mild stirring is carried out at a speed less than 200 rpm.
[0036] Typically, the condensation polymer is polyester.
[0037] Typically, the additive is carbon black with a particle size within the range of about 0.02 to about 1 microns.
[0038] Typically, the additive is a co-monomer containing a sulphonic acid group and which is capable of attaching to a cationic dye.
[0039] Typically, the co-monomer is at least one selected from the group consisting of 5-sulfoisophthalic acid (SIPA), 5-sulfoisophthalic acid dimethyl ester (SIPM), 5-sulfoisophthalic acid diglycolate (SIPEG) and alkali metal salts thereof.
[0040] In accordance with another aspect of the present invention there is provided a condensation polymer made from said continuous polymerization process.
[0041] In accordance with still another aspect of the present invention there is provided a yarn having filament breakage less than about 20 to about 30% made from said continuous polymerization process of any of the preceding claims.
[0042] In accordance with yet another aspect of the present invention there is provided a process for making a yarn from a condensation polymer wherein the spin pack pressure rise rate is attenuated by about 25 to about 35%.
[0043] In accordance with another aspect of the present invention there is provided a system for carrying out the continuous polymerization process comprising:
a. at least one initial reactor vessel; b. at least one final reactor vessel; c. optionally at least one intermittent reactor vessel; d. transfer lines for connecting the reactor vessels; and e. vigorous stirring means fitted in at least one of the intermittent reactor vessel.
[0049] Typically, the system further comprises mild stirring means fitted in at least one of the initial reactor vessels.
[0050] The process in accordance with the present invention includes employing plurality of stirred vessels (intermittent reactor vessels) in oligomer transfer line where least one additive is charged in slurry or solution through the stirring vessel. The vessel provides reactants residence time of less than ten minutes preferably less than five minutes. Any further vessels employed provide higher residence time proportionate to output. Use of such vessels in reactor system is independent of the any further additives. The Stirring vessel in the transfer line reduces chance of gel formation without necessitating use of diluents.
DETAILED DESCRIPTION OF THE INVENTION
[0051] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept and therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.
[0052] As used herein, “Small” vessel is small relative to the large un-stirred or less stirred reactors. “Small” is to be quantified as that size in a given throughput which provides less than 10 minute residence time, preferably less than 5 minute, while sizes of other bigger vessels/reactors in the line with same throughput will be proportionate with the higher residence times as chosen.
[0053] As used herein, the term “Vigorously” stirred vessel means wherein the stirring speed of vessel is about 400 to about 1000 rpm.
[0054] As used herein, the term “Additive” includes all possible additives which may or may not react with monomer.
[0055] In accordance with the present invention there is provided a continuous polymerization process for manufacturing a condensation polymer. The process comprising the following steps:
First step is employing an assembly comprising at least one initial reactor vessel, at least one final reactor vessel and optionally at least one intermittent reactor vessel. Second step is connecting said reactor vessels to each other through one or more transfer lines for leading the reactive materials from one vessel to another. Third step is adding the reactant components to at least one of the initial reactor vessels. Fourth step is optionally adding additives to any of said reactor vessels or in the transfer lines. Fifth step is stirring the reactive materials relatively vigorously in the intermittent reactor vessel after the addition of the additives.
[0061] Typically, the step of vigorous stirring is carried out at a speed of about 400 to about 1000 rpm for a period less than 10 minutes, preferably less than 5 minutes.
[0062] Next step is optionally stirring the reactive materials relatively mildly in the initial reactor vessel.
[0063] Typically, the step of mild stirring is carried out at a speed less than 200 rpm.
[0064] Finally the intermediates are obtained from at least one of the intermittent reactor vessel and the reaction product is obtained from the final reactor vessel.
[0065] In accordance with the present invention the polymerization is carried out at a temperature not lower than 285 deg C.
[0066] The additive used in the polymerization process in accordance with the present invention is carbon black with a particle size within the range of about 0.02 to about 1 microns.
[0067] In accordance with another embodiment of the present invention the additive is a co-monomer containing a sulphonic acid group and which is capable of attaching to a cationic dye.
[0068] The co-monomer employed is at least one selected from the group consisting of 5-sulfoisophthalic acid (SIPA), 5-sulfoisophthalic acid dimethyl ester (SIPM), 5-sulfoisophthalic acid diglycolate (SIPEG) and alkali metal salts thereof.
[0069] In accordance with another aspect of the present invention there is provided a condensation polymer made from said continuous polymerization process.
[0070] Typically, the condensation polymer is polyester.
[0071] In accordance with still another aspect of the present invention there is provided a yarn having filament breakage less than about 20 to about 30% made from said continuous polymerization process of any of the preceding claims.
[0072] In accordance with yet another aspect of the present invention there is provided a process for making a yarn from a condensation polymer wherein the spin pack pressure rise rate is attenuated by about 25 to about 35%.
[0073] In accordance with another aspect of the present invention there is provided a system for carrying out the continuous polymerization process comprising:
a. at least one initial reactor vessel; b. at least one final reactor vessel; c. optionally at least one intermittent reactor vessel; d. transfer lines for connecting the reactor vessels; and e. vigorous stirring means fitted in at least one of the intermittent reactor vessel.
[0079] Typically, the system further comprises mild stirring means fitted in at least one of the initial reactor vessels.
[0080] According to present invention, at least one vigorously stirred vessel (intermittent reactor vessel) is employed in a polymerization line that is otherwise devoid of reactors, to allow injection of additive solution in the oligomer while it is undergoing intense mixing. It works by immediate dispersion of the fluid additive into the oligomer, before the heat transfer from oligomer to additive droplet can cause freezing of oligomer at the interface of the additive fluid droplets. The stirring speed of vessel is about 400 to about 1000 rpm. Reduction in the rate of pressure rise up to 25% and reduction in the rate of broken filament during melt spinning up to 20% is achieved due to uniformity in the product obtained by such mixing. This vessel eliminates need of any other moving parts in reactor and reduces expenditure.
[0081] In one of the preferred embodiments a continuous polymerization process is provided to manufacture a semi-dull cationic dyeable polyalkylene terephthalate. Particularly, a continuous polymerization process to manufacture a semi-dull cationic dyeable polyalkylene terephthalate where alkali metal salt of 5-sulfoisophthalic acid dimethyl ester is converted to an alkali metal salt of 5-sulfoisophthalic acid diglycolate through a tranesterification reaction in at least one of an excess alkylene glycol is provided. Reduction in the rate of pressure rise during melt spinning, as well as reduction in broken filaments of textured yarn, is achieved while using cationic dyeable polyester is made in a continuous process that employs additive injection into oligomer in a stirred vessel.
[0082] Then the additive such as TiO 2 slurry in a glycol is added into a purified terephthalic acid (PTA) slurry in at least one glycol or into an oligomer formed. Here, TiO 2 is added first to the purified terephthalic acid slurry followed by addition of alkali metal salt of 5-sulfoisophthalic acid diglycolate to said oligomer after the transesterification. The mole ratio of alkylene glycol to purified terephthalic acid is around 2. An especially fine dispersion of PTA-MEG slurry (obtained through an otherwise known centrifugal separation/recirculating system) being added to PTA-MEG slurry, 20% converted SIPEG solution addition to molten oligomer undergoing intense mixing in highly agitated vessel in the continuous polymerization line.
[0083] About 15% to 45% of converted solution of alkali metal salt of 5-sulfoisophthalic acid diglycolate is injected into a oligomer transferline, alkali metal salt of 5-sulfoisophthalic acid diglycolate undergoes mixing with oligomer in a stirring vessel placed within oligomer transfer line. About 10 to 100 ppm of phosphoric acid is added in the oligomer transfer line. Use of phosphoric acid eliminates need of other additives like PEG. Elimination of addition of PEG which is thermally sensitive, thereby enabling the use of higher polymerization temp (˜295° C.) and hence provides higher productivity. The stirring speed inside the vessel may be about 400 to about 1000 rpm.
[0084] In another aspect polyalkylene terephthalate yarn made from a semi-dull cationic dyeable polyalkylene terephthalate is provided. The cationic dyeable polyalkylene terephthalate is manufactured through a continuous polymerization process, the process including: converting a alkali metal salt of 5-sulfoisophthalic acid dimethyl ester to a alkali metal salt of 5-sulfoisophthalic acid diglycolate through a transesterification reaction in at least one of excess alkylene glycol; adding additive slurry in a glycol into a purified terephthalic acid (PTA) slurry in at least one glycol or into an oligomer formed therefrom; injecting about 15% to 45% of converted solution of the alkali metal salt of 5-sulfoisophthalic acid diglycolate into a oligomer transferline wherein the alkali metal salt of 5-sulfoisophthalic acid diglycolate undergoes mixing with the oligomer in a stirring vessel placed within the oligomer transfer line.
[0085] In other possible embodiment, there can be additives which do not react with the monomer and hence do not convert into such a derivative as the glycolate but only remain soluble.
[0086] In a further possible embodiment, there can also be additives which neither react nor dissolve in the monomer but some complex or may even remain as neutral slurry and added through the stirred vessel.
[0087] In accordance with the preferred embodiment of the present invention carbon black slurry and small part of mono-ethylene glycol are added to oligomer at 290 deg C. in the small vessel at 400-1000 rpm vessel speed. This gives fine dispersion in high shear zone of stirred vessel by breaking the drop into small particles.
[0088] In further embodiment, a cationic dyeable polyester manufactured using vigorously stirred small vessel is provided where spin pack pressure rise of only 5 Bars/day for POY 128/72 is required and filament breakage is reduced to 10 per bobbin.
[0089] While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the invention. These and other changes in the preferred embodiment of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.
|
A continuous polymerization process where one or more stirred vessels (intermittent reactor vessels) are employed in oligomer transfer line for mixing additives. An additive is added in the stirred vessel either as a solution or as slurry. The additive may or may not be reactive with the other monomer of the polyester molecule. The additive reacts with the monomer and incorporates in the polymer backbone in one of the embodiment. One or more further additives are mixed with the pre-reactor monomer mix and are charged in the first reactor or charged through the stirred vessel in the form of single slurry or solution or multiple slurries or solutions. Any further vessels employed provide higher residence time proportionate to output and use of such vessels in reactor system is independent of the any further additives.
| 2
|
PRIORITY
[0001] This application makes reference to, claims all benefits inuring under 35 U.S.C. §119 and 120 from, and incorporates herein a provisional application filed in the U.S. Patent & Trademark Office on the 5 Feb. 2007 and there duly assigned Ser. No. 60/899,578.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method for transmitting data in a closed-loop multiple input multiple output system, and more specifically, a method for transmitting information regarding transmission format in a closed-loop multiple input multiple output system.
[0004] 2. Description of the Related Art
[0005] Orthogonal Frequency Division Multiplexing (OFDM) is a popular wireless communication technology to multiplex data in frequency domain.
[0006] A multiple antenna communication system, which is often referred to as multiple input multiple output (MIMO) system, is widely used in combination with OFDM technology, in a wireless communication system to improve system performance.
[0007] In a MIMO system, both transmitter and receiver are equipped with multiple antennas. Therefore, the transmitter is capable of transmitting independent data streams simultaneously in the same frequency band. Unlike traditional means of increasing throughput (i.e., the amount of data transmitted per time unit) by increasing bandwidth or increasing overall transmit power, MIMO technology increases the spectral efficiency of a wireless communication system by exploiting the additional dimension of freedom in the space domain due to multiple antennas. Therefore MIMO technology can significantly increase the throughput and range of the system.
[0008] When the transmission channels between the transmitters and the receivers are relatively constant, it is possible to use a closed-loop MIMO scheme to further improve system performance. In a closed-loop MIMO system, the receiver informs the transmitter of feedback information regarding the channel condition. The transmitter utilizes this feedback information, together with other considerations such as scheduling priority, data and resource availability, to optimize the transmission scheme.
[0009] A popular closed-loop MIMO scheme is MIMO precoding. With precoding, the data streams to be transmitted are precoded, i.e., pre-multiplied by a precoding matrix, before being passed on to the multiple transmit antennas in a transmitter.
[0010] In a contemporary closed-loop MIMO precoding scheme, when a transmitter precodes data before transmitting the data to a receiver, the transmitter informs the receiver of the precoding information such as an identification of the precoding matrix by transmitting dedicated pilots (also referred to as reference signals) or explicit control information that carries the precoding information. A significant problem with this approach is that the control information inefficiently consumes a significant amount of system resources and degrades the overall system throughput and capacity.
SUMMARY OF THE INVENTION
[0011] It is therefore an object of the present invention to provide an improved system and an improved method for transmitting data in a closed-loop multiple input multiple output (MIMO) system.
[0012] It is another object to provide an improved system and an improved method that is capable of transmitting data in a closed-loop MIMO system to save system resources and improve overall system throughput and capacity.
[0013] According to one aspect of the present invention, there is provided a system and a method for performing data transmission between a transmitter and a receiver, by generating a feedback message at the receiver in response to a reference signals or a pilot signal received from the transmitter, assigning an identifier for the feedback message, storing the feedback message in association with the identifier in the receiver, transmitting the feedback message and the identifier to the transmitter, determining, at the transmitter, the transmission format for data to be transmitted to the receiver based on the feedback message received from the receiver; and transmitting data and a control message, via the transmitter, using the determined transmission format, with the control message comprising the identifier of the feedback message based on which the transmission format is determined.
[0014] When the receiver receives data and the identifier of the feedback message from the transmitter, the receiver may look up information corresponding to the transmitted identifier and process the received data according to that information.
[0015] When the feedback message transmitted from the receiver and received by the transmitter contains errors, the transmitter may determine transmission format based on another feedback message received by the transmitter prior to the erroneous feedback message.
[0016] The identifier of the feedback message may be a number.
[0017] The number may indicate the index of the feedback message in a series of feedback messages transmitted by the receiver, with the smallest number indicating that the feedback message being the first one of the series of feedback message transmitted by the receiver.
[0018] Alternatively, the number may indicate the index of the feedback message in a series of feedback messages previously received by the transmitter, with the smallest number indicating that the feedback message being the most recent feedback message that is received by the transmitter.
[0019] Still alternatively, the number may a subframe number during which the feedback message is transmitted.
[0020] The number may be represented by binary digits.
[0021] The transmission format may be established in dependence upon frequency subbands in which the data is to be transmitted.
[0022] According to another aspect of the present invention, there is provided a system and a method for performing data transmission between a transmitter and a receiver, by generating a feedback message at the receiver in response to a reference signal or a pilot signal received from the transmitter, transmitting the feedback message to the transmitter, storing information in the feedback message in the receiver, deciding, at the transmitter, whether to transmit data to the receiver according to a first transmission format determined based on the feedback message received from the receiver, or according to a second transmission format which is not related to the feedback message received from the receiver, and transmitting data and a control message, by the transmitter, using either the first transmission format or the second transmission format, and when the first transmission format is used, informing the receiver that the transmission format is determined based on the feedback message received from the receiver, and when the second transmission format is used, informing the receiver that the transmission format is not related to the feedback message received from the receiver and transmitting the second transmission format to the receiver.
[0023] When the first transmission format is used, the transmitter may inform the receiver that the transmission format is determined based on the feedback message received from the receiver by including a bit ‘ 0 ’ in the control message transmitted to the receiver.
[0024] When the second transmission format is used, the transmitter may inform the receiver that the transmission format is not related to the feedback message received from the receiver by including a bit ‘ 1 ’ in the control message transmitted to the receiver.
[0025] According to still another aspect of the present invention, there is provided a system and a method for performing data transmission between a transmitter and a receiver, including the steps of generating a feedback message at the receiver in response to a reference signal or a pilot signal received from the transmitter, transmitting the feedback message to the transmitter, transmitting data from the transmitter to the receiver, transmitting a control message which carries a transmission format used for the data transmission, decoding, at the receiver, the control message in order to obtain the transmission format of the data transmitted from the transmitter, and, when the decoding is successful, processing the data received from the transmitter according to the obtained transmission format, and when the decoding is unsuccessful, processing the data received from the transmitter according to the most recent feedback message that the receiver has sent to the transmitter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] A more complete appreciation of this invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:
[0027] FIG. 1 is an illustration of an Orthogonal Frequency Division Multiplexing (OFDM) transceiver chain suitable for the practice of the principles of the present invention;
[0028] FIG. 2 is an illustration of a multiple input multiple output (MIMO) system suitable for the practice of the principles of the present invention;
[0029] FIG. 3 is an illustration of a single-code word MIMO scheme suitable for the practice of the principles of the present invention;
[0030] FIG. 4 is an illustration of a multi-code word MIMO scheme suitable for the practice of the principles of the present invention;
[0031] FIG. 5A and FIG. 5B are examples of precoding in a precoding MIMO-system suitable for the practice of the principles of the present invention;
[0032] FIG. 6 is an illustration of an example of MIMO precoding on different subbands suitable for the practice of the principles of the present invention;
[0033] FIG. 7 is an illustration of an example of MIMO rank on different subbands suitable for the practice of the principles of the present invention;
[0034] FIG. 8 is an illustration of an example of MIMO layer ordering on different subbands for a 2×2 MIMO system suitable for the practice of the principles of the present invention;
[0035] FIG. 9 is an illustration of control signaling in a wireless communication system suitable for the practice of the principles of the present invention;
[0036] FIG. 10 illustrates MIMO feedback and signaling according to a first embodiment of the principles of the present invention;
[0037] FIG. 11 illustrates MIMO feedback and signaling according to a second embodiment of the principles of the present invention;
[0038] FIG. 12 illustrates MIMO feedback and signaling according to a third embodiment of the principles of the present invention;
[0039] FIG. 13 illustrates MIMO feedback and signaling according to a fourth embodiment of the principles of the present invention;
[0040] FIG. 14 illustrates MIMO feedback and signaling according to a fifth embodiment of the principles of the present invention;
[0041] FIG. 15 illustrates MIMO feedback and signaling according to a sixth embodiment of the principles of the present invention;
[0042] FIG. 16 illustrates MIMO feedback and signaling according to a seventh embodiment of the principles of the present invention;
[0043] FIG. 17 is a flow chart showing the processing of MIMO signals according to an eighth embodiment of the principles of the present invention; and
[0044] FIG. 18 illustrates an example of Physical Downlink Control Channel (PDCCH) containing MIMO transmission format information according to the principles of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0045] The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.
[0046] FIG. 1 illustrates an Orthogonal Frequency Division Multiplexing (OFDM) transceiver chain. In a communication system using OFDM technology, at transmitter chain 110 , control signals or data 111 is modulated by modulator 112 and is serial-to-parallel converted by Serial/Parallel (S/P) converter 113 . Inverse Fast Fourier Transform (IFFT) unit 114 is used to transfer the signal from frequency domain to time domain. Cyclic prefix (CP) or zero prefix (ZP) is added to each OFDM symbol by CP insertion unit 116 to avoid or mitigate the impact due to multipath fading. Consequently, the signal is transmitted by transmitter (Tx) front end processing unit 117 , such as an antenna (not shown), or alternatively, by fixed wire or cable. At receiver chain 120 , assuming perfect time and frequency synchronization are achieved, the signal received by receiver (Rx) front end processing unit 121 is processed by CP removal unit 122 . Fast Fourier Transform (FFT) unit 124 transfers the received signal from time domain to frequency domain for further processing.
[0047] The total bandwidth in an OFDM system is divided into narrowband frequency units called subcarriers. The number of subcarriers is equal to the FFT/IFFT size N used in the system. In general, the number of subcarriers used for data is less than N because some subcarriers at the edge of the frequency spectrum are reserved as guard subcarriers. In general, no information is transmitted on guard subcarriers.
[0048] FIG. 2 illustrates a multiple input multiple output (MIMO) system. In a MIMO system, transmitter 130 and receiver 140 are respectively equipped with multiple antennas 135 and 145 . Therefore, transmitter 130 is capable of transmitting independent data streams 131 simultaneously in the same frequency band.
[0049] An example of a single-code word MIMO scheme is given in FIG. 3 . In case of single-code word MIMO transmission, a cyclic redundancy check (CRC) 152 is added to a single data stream 151 and then coding 153 and modulation 154 are sequentially performed. The coded and modulated symbols are then demultiplexed 155 for transmission over multiple antennas 156 .
[0050] In case of multiple-code word MIMO transmission, shown in FIG. 4 , data stream 161 is demultiplexed 162 into smaller stream blocks. Individual CRCs 163 are attached to these smaller stream blocks and then separate coding 164 and modulation 165 is performed on these smaller blocks. These smaller blocks are then transmitted via separate MIMO antennas 166 . It should be noted that in case of multi-code word MIMO transmissions, different modulation and coding can be used on each of the individual streams resulting in a so called PARC (per antenna rate control) scheme. Also, multi-code word transmission allows for more efficient post-decoding and interference cancellation because a CRC check can be performed on each of the code words before the code word is cancelled from the overall signal. In this way, only correctly received code words are cancelled to avoid any interference propagation in the cancellation process.
[0051] When the transmission channels between the transmitters and the receivers are relatively constant, it is possible to use a closed-loop MIMO scheme to further improve system performance. In a closed-loop MIMO systems, the receiver informs the transmitter of the feedback information regarding the channel condition. The transmitter utilizes this feedback information, together with other considerations such as scheduling priority, data and resource availability, to optimize the transmission scheme.
[0052] A popular closed-loop MIMO scheme is MIMO precoding. With precoding, the data streams to be transmitted are precoded, i.e., pre-multiplied by a precoding matrix, before being passed on to the multiple transmit antennas in a transmitter.
[0053] An optional precoding protocol that employs a unitary pre-coding before mapping the data streams to physical antennas is shown in FIGS. 5A and 5B . The optional precoding creates a set of virtual antennas (VA) 171 before the pre-coding. In this case, each of the codewords is potentially transmitted through all the physical transmission antennas 172 . Two examples of unitary precoding matrices, P 1 and P 2 for the case of two transmission antennas 172 may be:
[0000]
P
1
=
1
2
[
1
1
1
-
1
]
,
P
2
=
1
2
[
1
1
j
-
j
]
(
1
)
[0054] Assuming modulation symbols S 1 and S 2 are transmitted at a given time through stream 1 and stream 2 respectively. Then the modulation symbol T 1 after precoding with matrix P 1 in the example as shown in FIG. 5A and the modulation symbol T 2 after precoding with matrix P 2 in the example as shown in FIG. 5B can be respectively written as:
[0000]
T
1
=
P
1
[
S
1
S
2
]
=
1
2
[
1
1
1
-
1
]
×
[
S
1
S
2
]
=
1
2
[
S
1
+
S
2
S
1
-
S
2
]
(
2
)
T
2
=
P
2
[
S
1
S
2
]
=
1
2
[
1
1
j
-
j
]
×
[
S
1
S
2
]
=
1
2
[
S
1
+
S
2
jS
1
-
jS
2
]
[0000] Therefore, the symbols
[0000]
T
11
=
(
S
1
+
S
2
)
2
and
T
12
=
(
S
1
-
S
2
)
2
[0000] will be transmitted via antenna 1 and antenna 2 , respectively, when precoding is done using precoding matrix P 1 as shown in FIG. 5A . Similarly, the symbols
[0000]
T
21
=
(
S
1
+
S
2
)
2
and
T
22
=
(
jS
1
-
jS
2
)
2
[0000] will be transmitted via antenna 1 and antenna 2 , respectively, when precoding is done using precoding matrix P 2 as shown in FIG. 5B . It should be noted that precoding is done on an OFDM subcarrier level before the IFFT operation as illustrated in FIGS. 5A and 5B .
[0055] An example of MIMO precoding is Fourier-based precoding. A Fourier matrix is a N×N square matrix with entries given by:
[0000] P mn =e j2πmn/N m,n= 0,1, . . . ( N− 1) (3)
[0056] A 2×2 Fourier matrix can be expressed as:
[0000]
P
2
=
1
2
[
1
1
1
j
π
]
=
1
2
[
1
1
1
-
1
]
(
4
)
[0057] Similarly, a 4×4 Fourier matrix can be expressed as:
[0000]
P
4
=
1
4
[
1
1
1
1
1
j
π
/
2
j
π
j3
π
/
2
1
j
π
j
2
π
j
3
π
1
j3
π
/
2
j
3
π
j9
π
/
2
]
=
1
4
[
1
1
1
1
1
j
-
1
-
j
1
-
1
1
-
1
1
-
j
-
1
j
]
(
5
)
[0058] Multiple precoder matrices can be defined by introducing a shift parameter (g/G) in the Fourier matrix as given by:
[0000]
P
mn
=
j
2
π
n
N
(
n
+
g
G
)
m
,
n
=
0
,
1
,
…
(
N
-
1
)
(
6
)
[0059] A set of four 2×2 Fourier matrices can be defined by taking G=4. These four 2×2 matrices with g=0, 1, 2 and 3 are written as:
[0000]
P
2
0
=
1
2
[
1
1
1
-
1
]
P
2
1
=
1
2
[
1
1
j
π
/
4
-
j
π
/
4
]
(
7
)
P
2
2
=
1
2
[
1
1
j
π
/
2
j
3
π
/
4
]
P
2
3
=
1
2
[
1
1
j
3
π
/
4
-
j
3
π
/
4
]
(
8
)
[0060] In a transmission path from a base station to a user equipment (UE), i.e., downlink transmission, the precoding matrix is usually determined in dependence upon a precoding feedback information that is transmitted by the user equipment to the base station. The precoding feedback information typically includes precoding-matrix identity.
[0061] When the total bandwidth in an OFDM system is divided into a plurality of subbands, each subband being a set of consecutive subcarriers, due to frequency-selective fading in the OFDM system, the optimal precoding for different subbands (SBs), can be different, as shown in one example illustrated in FIG. 6 . That is, in FIG. 6 , different SBs use different precoding matrix. Subband 1 (SB 1 ) which includes continuous OFDM subcarriers 1 through 64 , use precoding matrix P 2 2 ; SB 2 which includes continuous OFDM subcarriers 65 through 128 , use precoding matrix P 2 1 , etc. Therefore, the precoding feedback information is transmitted on a subband basis. Moreover, due to feedback errors, the base station also needs to inform the user equipment of the precoding information used on transmitted subbands. This results in additional signaling overhead in the downlink.
[0062] Besides precoding information, another form of feedback information is rank information, i.e., the number of MIMO layers. A MIMO layer is a spatial channel that can carry data symbols. It is well known that even when a system can support 4×4 MIMO, rank-4 (4 MIMO layers) transmissions are not always desirable. The MIMO channel experienced by the UE generally limits the maximum rank that can be used for transmission. In general for weak users in the system, a lower rank transmission is preferred over a higher rank transmission from the throughput perspective. Moreover, due to frequency-selective fading, optimal rank may be different on different subbands. As shown in the example of FIG. 7 , SB 1 uses rank-1 transmission; SB 2 uses rank-2 transmission, etc. Therefore, the UE needs to include the rank information in the feedback information on a subband basis. Also, due to a possibility of feedback errors, the base station additionally needs to indicate the transmitted MIMO rank on different subbands. The rank information can also be common across the subbands, that is, a single rank value is reported for all the subbands. In any case, this results in additional overhead on the downlink.
[0063] Still another form of MIMO feedback information is layer ordering information. In the example of FIG. 8 , the layer order for SB 1 , SB 2 , SB 4 , SB 5 and SB 8 is layer 2 , and then layer 1 ; while the layer order for SB 3 , SB 6 and SB 7 is layer 1 , and then layer 2 . The layer ordering information is generally transmitted by the UE and also indicated by the base station in control signaling on the downlink. The ordering of layers can be based on the channel quality they experience or other similar criteria.
[0064] Another form of MIMO feedback information which applies to both MIMO and non-MIMO scenarios is the selected subbands for transmission. In this case, the MIMO feedback information such as precoding, rank, IDs of selected layers and layer ordering is provided for the selected subbands only. In this case, however, both the UE and the base station need to signal the information on the selected subbands.
[0065] In packet-based wireless data communication systems, a control signal accompanies the data transmission as shown in FIG. 9 . In the 3 rd Generation Long Term Evolution (3G LTE) system, the control channel that carries the control signal is referred to as Physical Downlink Control Channel (PDCCH). The PDCCH carries information such as UE ID, resource assignment information, Payload size, modulation, Hybrid Automatic Repeat-reQuest (ARQ) HARQ information, MIMO related information.
[0066] As described above, when the base station transmits data to the user equipment, the base station determines a transmission format in dependence upon the MIMO information that is inform by the user equipment through a feedback message. Contemporarily, the base station transmits the MIMO information, based on which the transmission format of the data is determined, together with the data, to the user equipment.
[0067] In the present invention, we have constructed a protocol where the base station does not need to explicitly signal those items of the MIMO information such as precoding, rank, selected MIMO layers and layer ordering, etc. in a downlink transmission. The base station simply indicates the identification of the feedback message to the user equipment in conformance with the protocol used by the base station to perform the MIMO transmission format.
[0068] FIG. 10 illustrates MIMO feedback and signaling according to a first embodiment of the principles of the present invention. In this first embodiment, a base station (BS) 210 simply indicates the identification of the feedback message to UE 220 in accordance with the protocol used by base station 210 to perform the MIMO transmission format. Specifically, at time t, US 220 transmits feedback message A 221 in response to a reference signal or a pilot signal received from base station 210 . Feedback (FB) message A 221 contains information such as selected subbands, precoding, rank and layer ordering, etc. At the same time, when UE 220 transmits feedback message A 221 , UE 220 also stores the information in feedback message A 221 in a buffer (not shown). At time (t+1), base station 210 sends control message 222 and data 223 to UE 220 . Instead of transmitting feedback message A back to UE 220 , base station 210 indicates in the control message that the format for data transmission is determined based on feedback message A 221 . Subsequently, UE 220 already knows the feedback information feedback message A and therefore reads the feedback message A 221 stored in the buffer and processes the received data transmission according to the information in feedback message A. In this way, base station 210 does not have to explicitly transmit the precoding or other MIMO information such as rank and layer ordering to UE 220 in the downlink transmission. At time (t+2), base station 210 receives updated feedback information carried in feedback message B 224 from UE 220 . Feedback message B 224 is generated in response to another reference signal received from base station 210 . At time (t+3), base station 210 performs data transmission to UE 220 using the updated feedback information feedback message B 224 . Base station 210 also indicates in control message 225 that the condition for data transmission including precoding, rank and layer ordering is determined based on feedback message B. UE 220 then processes received information data 226 according to the information indication in feedback message B 224 that UE 220 has already stored.
[0069] In a second embodiment according to the principles of the present invention as shown in FIG. 11 , base station 210 uses feedback from an earlier feedback message because the most recent feedback message contains error as detected by some erasure detector or Cyclic Redundancy Check (CRC) unit. In the example of FIG. 11 , base station 210 performs a transmission at time (t+3) according to feedback message A 221 received earlier at time t because feedback message B 227 received at time (t+2) contained errors. UE 210 then processes the received data 229 according to the information, such as precoding, rank and layer ordering information, carried in feedback message A 221 . This scheme assures that the UE always decodes the information using a correct format as confirmed by the base station.
[0070] In a third embodiment of the principles of the present invention as shown in FIG. 12 , the Feedback (FB) messages are numbered with sequence numbers 0 , 1 , 2 and 3 in the order of generation by UE 220 . This would require 2-bits overhead to indicate the sequence numbers 0 through 3 . Base station (BS) 210 informs UE 220 of the sequence number of the FB message that is used for determining format for MIMO transmission. In the third embodiment as shown in FIG. 12 , the time for data transmission is divided into a plurality of subframes. In subframe # 1 , BS 210 receives FB # 0 message. In subframe # 2 , BS 210 performs data transmission to UE 220 according to the transmission format determined based the information carried in FB# 0 , and simultaneously receives FB# 1 message from UE 220 . In subframe# 3 , the transmission is performed by BS 210 according to the transmission format determined based on FB# 1 message received in subframe# 2 , and BS 210 simultaneously receives FB# 2 message from UE 220 . But BS 210 detects that FB# 2 message contains error. Therefore, base station 210 ignores FB# 2 message and performs transmission according to FB# 1 message in subframe# 4 . This scheme assures that UE always know the FB message used to determine the format (i.e. precoding, rank and layer ordering etc.) of the MIMO transmission.
[0071] In a fourth embodiment according to the principles of the present invention as shown in FIG. 13 , the Feedback (FB) messages transmitted by UE 220 are not sequentially numbered. Instead, base station 210 transmits one of four possible combinations of binary symbols 0 and 1. These combinations indicate which previously received FB message is used to determine format for MIMO transmission. Based on the received combination, UE 220 can determine which FB message is actually used for MIMO transmission in a given subframe. In the example of FIG. 13 , in subframe# 2 and subframe# 3 , base station 210 transmits FB( 0 ) message (i.e., combination of ‘0’ and ‘0’) in control signal, which indicates that the most recent FB message was used for determining the MIMO transmission format. In subframe# 3 , FB message is received in error, and therefore in subframe# 4 , base station 210 indicate FB( 1 ) message (i.e., combination of ‘0’ and ‘1’) which means that the FB message received prior to the most recent message is used for determining MIMO transmission format. UE 220 can then processes the received signal according to the FB message which is sent in subframe# 2 because UE 220 knows that FB message in subframe# 3 was received in error. In subframe# 5 , the received FB message contains error, and therefore in subframe# 6 base station 210 transmits FB( 1 ) message to UE 220 to indicate that the transmission format in subframe# 6 was determined based on the FB message that is earlier than the most recent FB transmitted by UE 220 . In subframe# 6 , the received FB message contains error again, and therefore in subframe# 7 base station 210 transmits FB( 2 ) message (i.e., combination of ‘1’ and ‘0’) to UE 220 to indicate that the transmission in subframe# 7 was determined based on the FB message received before the two recent FB messages received from the UE. Note that the formats for transmission by BS 210 in subframe# 6 and subframe# 7 are the same because there was no correctly received FB message in sunframe# 6 and subframe# 7 . It should also be noted that the same goal can be achieved if the combinations indicate how many previous consecutive FB messages were received in errors with indication of 0 through 3.
[0072] In a fifth embodiment according to the principles of the present invention as shown in FIG. 14 , the Feedback (FB) messages are not sequentially numbered. We also assume that MIMO FB messages are sent in every 2 subframes. Note that the MIMO feedback rate in the time domain can be configured by the network. In the fifth embodiment, base station 210 indicates the subframe number in which the FB is received and is used for determining MIMO transmission format in the downlink. This indication is done on the downlink control channel that accompanies the downlink data transmission. As shown in FIG. 14 , in subframe# 2 and subframe# 3 , the MIMO transmission format, which includes precoding, rank, IDs of selected layers and layer ordering, is determined using the FB message received in subframe# 1 . This is indicated by FB( 1 ) indication. In subframe# 4 through subframe# 7 , the MIMO transmission format is determined according to the FB message received in sub frame# 3 . This is indicated by FB( 3 ) indication. Note that FB message in subframe# 5 is received in error and hence is not used. Finally in subframe# 8 , the MIMO format corresponding to FB message in subframe# 7 is used.
[0073] In a sixth embodiment of the current invention, a 1-bit indication is used to indicate whether the MIMO transmission format including precoding, rank, IDs of selected layers and layer ordering information is determined based on the most recent UE feedback message or not. If the base station decides to use another transmission format than the one determined based on the most recent UE feedback message for data transmission, this other transmission format is explicitly transmitted to the UE as shown in FIG. 15 . A ‘0’ in the control information indicates that the MIMO transmission format is determined using the most recent FB message received. A ‘1’ in the control information indicates that the MIMO transmission format is carried explicitly. The MIMO transmission format can then be separately coded, modulated or jointly coded, modulated with other downlink control information and transmitted by the base station. An explicit MIMO format indication may be necessary when the base station uses different MIMO format than one reported by the UE or if the most recent FB message was received erroneously and base station uses MIMO format according to an earlier FB message.
[0074] In a seventh embodiment according to the principles of the current invention as shown in FIG. 16 , the MIMO feedback is provided for part of the whole bandwidth in a given FB message. In the example of FIG. 16 , FB# 1 covers the lower half of the bandwidth while FB# 2 covers the upper half of the bandwidth. In this case, the base station can indicate that MIMO transmission format (precoding, rank, IDs of selected layers and layer ordering etc.) is determined either according to FB# 1 if the UE is scheduled in the left half of the bandwidth or according to FB# 2 if the UE is scheduled in the right half of the bandwidth. If the UE is scheduled in both left and right halves then the base station needs to indicate both FB# 1 and FB# 2 . Also, the base station can simply indicate the MIMO transmission format by 1-bit indication if the most recent FB# 1 and FB# 2 are used for transmission or MIMO transmission format is explicitly indicated.
[0075] In an eighth embodiment according to the principles of the current invention as shown in FIG. 17 , the base station always transmit the MIMO transmission format explicitly, and the user equipment always try to decode the control message that contains the MIMO transmission format information. FIG. 17 illustrates a flow chart of the processing of MIMO signals according to the principles of the current invention. In this embodiment, no 1-bit indication informing the UE if MIMO format is explicitly signaled or not is used in the regular control message. After a UE receives control message through control channels from a base station (step S 10 ), the UE decodes the control message carried through the control channels at step S 20 to determine which part of the control message carries MIMO transmission format information and which part of the control message carries information regarding the UE ID/CRC, etc. Then at step S 30 , the UE determines whether the decoding process performed at step S 20 is successful. If the decoding process is not successful, the UE stops the process (step S 50 ). Otherwise, if the decoding process at step S 20 is successful, the UE tries to decode the part of the control message that contains the MIMO transmission format (precoding, rank and selected layers etc.) at step S 40 . Then at step S 60 , the UE determines whether the decoding process performed at step S 40 is successful. If the decoding succeeds, the UE processes the signal received from the base station according to MIMO transmission format information contained in the control message (step S 80 ). If the decoding fails, the UE processes the signal received from the base station assuming that the base station used the MIMO transmission format that is determined based on to most recent Feedback message transmitted from the UE.
[0076] In a ninth embodiment according to the principles of the current invention, the base station uses a plurality of common MIMO transmission formats (precoding, rank and selected layers etc.) on all the data scheduled to be transmitted to the UE in cases when the base station does not use the MIMO transmission format that is determined based on the FB message reported by the UE. In this way, a MIMO format indication field including a fixed amount of bits (2-6 bits) can be included in the Physical Downlink Control Channel (PDCCH) as shown in Format I in FIG. 18 . In case where the BS uses the subband specific MIMO transmission format determined based on the UE feedback, a certain combination of bits (e.g. ‘00’ for 2-bits and ‘000000’ for 6-bits) included in the MIMO format field will indicate this. As shown in Table 1, ‘000000’ in the MIMO format indication field in PDCCH indicates that the base station uses the MIMO transmission format based on the most recent FB message transmitted from the UE; ‘000001’ in the MIMO format indication field in PDCCH indicates that the base station uses the MIMO transmission format based on one-earlier than the most recent FB message transmitted from the UE; ‘000010’ 000001’ in the MIMO format indication field in PDCCH indicates that the base station uses the MIMO transmission format based on two-earlier than the most recent FB message transmitted from the UE. Therefore, if the base station is using subband specific MIMO transmission format determined based on UE feedback, the MIMO format field in the PDCCH will indicate this. In case when the base station overrides the UE feedback, the base station transmits a MIMO format indication selected from ‘000011’ through ‘111111’ to the UE to indicate that a common MIMO format selected from the sixty-one common MIMO transmission formats will be used for all the allocated resource blocks (RB, i.e., the minimum frequency subband) and indicated in the MIMO format field. It should be noted that in this case another format Format 0 (not including MIMO format field) may be required for PDCCH. This format can be used in cells not supporting MIMO. It should be noted that there will be no need to perform a blind detection between Format 0 and Format I because these formats will not be used simultaneously in a cell.
[0000]
TABLE 1
An Example of MIMO format indication on the downlink for support of
SU-MIMO
6-bits MIMO
Information
(MI) in the
downlink
Purpose
‘000000’
BS uses MIMO transmission format determined based
on the most recent Feedback from the UE
‘000001’
BS uses MIMO transmission format determined based on
one-earlier than the most recent UE Feedback from the UE
(assuming BS detected errors in the most recent UE
Feedback)
‘000010’
BS uses MIMO transmission format according to two-
earlier Feedback than the most recent UE Feedback
from the UE UE (assuming BS detected two consecutive
errors in the UE Feedback)
‘000011-
BS overrides the UE feedback and uses a common MIMO
111111-’
transmission format for all the RBs allocated to the UE.
This common MIMO transmission format is indicated by
one out of the 61 combinations (4-63).
[0077] It should be noted that in the ninth embodiment of the present invention, the UE needs to store the information carried in the three previous Feedback messages. Based upon the MIMO Information (MI) field in the PDCCH, the UE uses the information in the corresponding Feedback message or the MIMO format indicated in the MIMO format field to process the received MIMO signal. It should be noted that this approach also applies to the schemes where UE Feedback is provided for the “best-M” subbands (the subbands having the highest channel quality indication) or over part of the total bandwidth.
[0078] It is also possible to use another bits combination in another field in the control message such as payload size field, modulation, HARQ information or resource allocation fields indicating that Node-B is following the MIMO format according to the feedback from the UE.
|
A method for performing data transmission between a transmitter and a receiver. The method includes the steps of generating a feedback message at the receiver in response to data received from the transmitter, assigning an identifier for the feedback message, storing the feedback message in association with the identifier in the receiver, transmitting the feedback message and the identifier to the transmitter, determining, at the transmitter, transmission format for data to be transmitted to the receiver based on the feedback message received from the receiver; and transmitting data and a control message, by the transmitter, using the determined transmission format, with the control message comprising the identifier of the feedback message based on which the transmission format is determined.
| 7
|
FIELD OF INVENTION
This invention relates to electrical switch means and, in particular, to an electrical slide switch of improved construction and simplicity.
BACKGROUND OF THE INVENTION
Typically, a slide switch is characterized by a base defining at least two contacts and an assembly including a slider and a bridging contactor. When the assembly is attached to the base, the slider provides for sliding movement of the bridging contactor relevant to the spaced-apart contacts for changing switch positions.
BRIEF STATEMENT OF THE PRIOR ART
The prior art includes numerous slide switch designs which employ an assembly of two or more leaf spring members as the spring contact member such as shown in U.S. Pat. No. 3,461,252.
The prior art is also replete with attempts to obtain a snap action in the making and breaking of electrical contacts. One attempt, shown in U.S. Pat. No. 3,072,757, employs a single element spring contact member which is bowed outwardly at a central portion to provide a central protrusion that rides over the contact poles.
Another prior art patent of interest with regard to the present invention is U.S. Pat. No. 3,917,921. This reference describes a switch having a U-shaped actuator which fits over (cantilevered) lead contacts. One of the leads is L-shaped in a contact area, while the other is L-shaped with an S-shaped contact section. Actuation of the switch is achieved by interaction of a downwardly projecting actuating member formed on the slider which contacts the upward bend to force the downward bend into contact with the contact area when the switch is closed. Apparent shortcomings of this switch construction are that the surface between the contact areas do not undergo a sliding and, thereby, cleaning motion and that the leads must be formed from highly resilient material which increases manufacturing costs.
Other prior art patents of some interest include U.S. Pat. Nos. 3,221,115 issued Nov. 30, 1965 to Feher; 3,139,746 issued Feb. 13, 1979, to Farrell et al; 4,035,594 issued July 12, 1977, to McKinney; 3,719,788 issued Mar. 6, 1973, issued to Holland; 4,081,632 issued Mar. 28, 1978 to Schaffeler; 4,092,504 issued May 30, 1978, to Kotaka; 4,095,060 issued June 13, 1978, to Keprda; 2,762,880 issued Sept. 11, 1956, to Hathorn et al; 2,966,560 issued Dec. 27, 1960, to Gluck; and 3,072,757 issued Jan. 8, 1963 to Gluck.
These patents are mentioned as being representative of the prior art and other pertinent patents/references may exist. None of the above cited patents are deemed to affect the patentability of the present claimed invention.
In contrast to the prior art, the present invention provides a slide switch assembly which utilizes a free-ended serpentine shaped spring bridging contactor pivotally held approximately at its mid region which cooperates with a camming surface(s) on a slider to combine the advantages of both a sliding and rocking action in moving from one switch condition to the other, effects self-detenting of the bridging contact in the selected switch "on" and "off" position and involves a minimum of associated parts.
SUMMARY OF THE INVENTION
The invention comprises a slide switch construction which has particular utility for side-by-side slide switches housed in a dual in-line programming (DIP) switch package. The stationary contacts of each switch are flat and spaced across the bottom of the switch housing. The bridging contactor comprises a serpentine shaped leaf spring which is pivotally or rotatably held approximately at its mid region. Two upper curved (apex) portions of the bridging contactor cooperate with a camming element(s) on a slide track actuator to cause the bridging contactor to undergo a compound motion, i.e. a pivoting and sliding motion, during the switch make/break transactional operation.
Detent means is defined by at least one upper curved portion of the bridging contactor and by a camming element on the slide (track) actuator.
Accordingly, an object of the invention is to provide a new and improved slide switch.
It is a further object of the invention to provide a bridging contactor which combines the advantages of both a sliding and rocking action in moving from one switch condition to the other.
It is a further object of the invention to provide a new and improved bridging contactor having a serpentine shape.
It is a further object of the invention to provide a free-ended bridging contactor.
It is a further object of the invention to provide a new and improved bridging contactor which is pivotally held approximately at its mid region.
It is a further object of the invention to provide a free-ended serpentine shaped leaf spring bridging contactor pivotally held approximately at its mid region.
Another object of the invention is to provide a new and improved bridging contactor which cooperates with a slide (track) actuator to combine the features/advantages of both a sliding and rocking action in moving from one switch condition to the other, and effects self-detenting in at least one switch position.
Other objects and advantages will be apparent to those skilled in the art from the detailed description of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate the preferred embodiments of the present invention by way of example. Like numerals refer to like parts throughout.
FIG. 1 is a cross-sectional side view of one switch section constructed in accordance with the invention with the contacts open;
FIG. 2 is a cross-sectional side view of one switch section constructed in accordance with the invention with the contacts closed;
FIG. 3 is a top view of the bridging contactor constructed in accordance with the invention;
FIG. 4 is an upturned perspective view of the slider shown in FIGS. 1 and 2;
FIG. 5 is a partial top view of a housing having a plurality of side-by-side elongate cavities in a DIP switch package constructed in accordance with the invention with the top cover and slider assembly removed;
FIG. 6 is a partial top view of the DIP switch package shown in FIG. 5 with the top cover and slider utilized; and
FIGS. 7A and 7B are cross-sectional side views of an alternative embodiment of the invention with the contacts open and closed, respectively.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, particularly FIGS. 1 through 5, there is shown a slide switch 10 constructed in accordance with the invention to have a simple on-off action comprising a housing which includes a top cover 11 and a base member 12, two spaced apart flat stationary contacts 13 and 14 secured in the base member 12, a bridging contactor 15 having a serpentine or sinusoidal shape and a slider, or operating member, 16 disposed within the slide switch 10. The contacts 13, 14 have leadouts 17 and 18, respectively, projecting downwardly through the base member 12.
As noted above, the switch housing includes a top cover 11 and a base member 12. The housing may be formed of any suitable insulating material. The base member 12 includes a peripheral ledge 19 and a longitudinal cavity 20 extending from one end wall of the switch to the other. The cavity 20 is open at the top and has two intermediate slots 21 and 22 for accommodating the rocker arm means 23 and 24, respectively, of the bridging contactor 15. The top cover 11 includes downwardly projecting wall means 25 which is supportably mounted on the ledge 19 of the base portion 12, a recess or cavity 26 for receiving the slider 16 and an elongate aperture 27 to accommodate the slide head portion 28.
The bridging contactor 15 is formed from resilient sheet material, and has a serpentine configuration with at least two upper and two lower curved portions 29, 30 and 31, 32, respectively. The bridging contactor 15 is disposed within the longitudinal cavity 20 of the base member 12 to permit rocking or pivoting about the lower curved portion 32 while being maintained in electrical contact with switch (terminal) contact 14.
As noted above, the rocker or pivot arm means 23, 24 extend sidewards into a respective slot 21, 22, and are adapted to cooperate with the slots 21, 22 for defining the longitudinal position of the bridging contactor 15 within cavity 20. According to another feature of the invention, the pivot arm means 23 and 24 are contoured to cooperate with slots 21 and 22, respectively, to enable pivoting of the bridging contactor 15. The pivot arm means may also be adapted to permit sliding engagement between the lower curved portion 32 and contact 14 during the switch make/break operation.
Lower curved portion 31 is contoured to permit sliding engagement with contact 13 during the switch make/break operation.
The two upper curved (apex) portions 29, 30 are contoured and spaced-apart, at a distance approximately equal to or less than the length of the flat track portion 33 of slider 16, to cooperate with the slide camming surfaces 34, 35, respectively, to effect pivoting, compressing and detent holding of the bridging contactor 15 during switching "on" and "off" transaction.
The slider 16 is movable between the "off" position (shown in FIG. 1) and the "on" position (shown in FIG. 2) and includes an upwardly extending head portion or knob 28 protruding through the elongate aperture 27 in the top cover 11, and a flat track portion 33 having its ends forming inclined camming surfaces 34 and 35.
The base portion 36 of slider 16 overhangs cavity 20 and is in sliding engagement with the flat surface 37 of base member 12. The flat track portion 33 projects downwardly into the longitudinal cavity 20 and rides on the upper curved portions 29 and/or 30 of the bridging contactor 15.
With reference to FIGS. 5 and 6, it can be seen that the invention has particular utility in applications where a plurality of slide switches are arranged side-by-side in a common housing to form a dual in-line programming (DIP) switch package. The stationary contacts 13 and 14 are shown in phantom outline. The slider head 28 and/or the elongate aperture 27 may contain bifucated cut-outs 38 and 39, to facilitate slider actuation with a small or pointed object.
OPERATION
As mentioned, the slider 16 is in the "off" position in FIG. 1, and when the projecting head portion 28 is subjected to an operating force directed from right to left in the Figure, the slider 16 moves to the left. As the slider 16 moves to the left, the (first) upper curved portion 29 abuts camming surface 34 which drives the (second) lower curved portion 31 in a downward direction. As the (first) upper curved portion 29 is cammed downward, the (second) lower curved portion 31 is forced into electrical contact with switch contact 13 and causes it to slide or wipe across contact 13 with outward bowing relative to the (first) lower curved portion 32.
Continued operating force on the slider 16 to the left will force the bridging contactor 15 into a fully compressed state (not shown) with both upper curved portions 29, 30 at or near an unstable (straddling) position between camming surfaces 34, 35 respectively, and the flat track portion 33. Further operating force on the slider 16 to the left results in the (second) upper curved portion 30 being cammed/biased in an upward direction resulting in a pivoting or rocking motion of the bridging contactor 15 about the lower curved portion 32 and detenting of the upper curved portion 30 with camming surface 35. Since the (first) upper curved portion 29 is compressed under the flat track portion 33 of slider 16, the lower curved portions 31, 32 are pressed or biased yeildingly into electrical (bridging) contact with switch contacts 13, 14, respectively.
To turn the switch off, an operating force directed from left to right is applied to the slider 16. With rightward movement of slider 16, upper curved portion 30 contacts camming surface 35 which forces it downward into the unstable (straddling) position (not shown) with consequential full compression of the bridging contactor 15. Continued rightward movement of slider 16 causes the bridging contactor 15 to pass through the unstable position whereupon it rotates in a clockwise manner forcing upper curved portion 29 upward into contact with base 36 of slider 16.
From the above it should be appreciated that the wiping or rubbing action of the lower curved portions 31, 32 on the flat contacts 13, 14, respectively, sweeps off oxide films, and pollutants facilitating electrical contact therebetween. And that the rocking and self-detenting action of the bridging contactor 15 are facilitated by the actions of the free-end portions 40, 41, i.e., the none cantilevered and none affixed ends, of the bridging contactor 15.
With reference to FIGS. 7A and 7B, an alternative construction of the slide switch is shown. The slide switch assembly shown in these drawings is similar to that shown in FIGS. 1 and 2 with the exception that the slider 42 includes a split slide track 33A, 33B having an intermediate upturned trough or recess 42, with tapered side walls 44, 45. At least one of the tapered side walls, in this embodiment side wall 44, forms a camming surface which coacts with upper curved portion 29 to effect both a detent holding in the switch "off" position (shown in FIG. 7A) and for camming the bridging contactor 15 into the switch "on" position (shown in FIG. 7B) when the slider 42 is subjected to an operating force directed from left to right.
While there has been shown what is considered to be the preferred embodiments of the invention, it is desired to secure in the appended claims all modifications as fall within the true spirit and scope of the invention.
|
A slide switch construction including two spaced-apart stationary contacts and a free-ended serpentine shaped leaf spring bridging contactor which undergoes both a rocking and sliding motion in making/breaking bridging contact across the stationary contacts. The slide actuator includes camming surfaces which in addition to urging the bridging contactor into the make/break position, coacts therewith to provide a detent holding of the switch in the "on" and "off" position.
| 7
|
CONTINUING DATA
[0001] The present application is a continuation-in-part of U.S. patent application Ser. No. 13/231,077 filed Sep. 13, 2011 which is a continuation-in-part of U.S. patent application Ser. No. 12/924,628 filed Sep. 30, 2010 which claims priority to the following:
[0000] (1) U.S. Provisional Patent Application No. 61/277,871 filed Sep. 30, 2009; (2) U.S. Provisional Patent Application No. 61/281,046 filed Nov. 12, 2009; (3) U.S. Provisional Patent Application No. 61/336,242 filed Jan. 19, 2010; (4) U.S. Provisional Patent Application No. 61/339,273 filed Mar. 2, 2010; which is further a continuation-in-part of U.S. patent application Ser. Nos. 12/806,114; 12/806,117; 12/806,121; 12/806,118; 12/806,126; 12/806,113, all filed Aug. 5, 2010, all of which claim priority to: (1) U.S. Provisional Patent Application No. 61/273,518 filed Aug. 5, 2009; (2) U.S. Provisional Patent Application No. 61/273,536 filed Aug. 5, 2009; (3) U.S. Provisional Patent Application No. 61/277,871 filed Sep. 30, 2009; (4) U.S. Provisional Patent Application No. 61/281,046 filed Nov. 12, 2009; (5) U.S. Provisional Patent Application No. 61/336,242 filed Jan. 19, 2010; (6) U.S. Provisional Patent Application No. 61/339,273 filed Mar. 2, 2010; all of which are further continuations-in-part of U.S. patent application Ser. No. 12/803,805 filed Jul. 7, 2010 which claims priority to: (1) U.S. Provisional Patent Application No. 61/224,904 filed Jul. 12, 2009; (2) U.S. Provisional Patent Application No. 61/273,518 filed Aug. 5, 2009; (3) U.S. Provisional Patent Application No. 61/273,536 filed Aug. 5, 2009; (4) U.S. Provisional Patent Application No. 61/277,871 filed Sep. 30, 2009; (5) U.S. Provisional Patent Application No. 61/281,046 filed Nov. 12, 2009; (6) U.S. Provisional Patent Application No. 61/336,242 filed Jan. 19, 2010; (7) U.S. Provisional Patent Application No. 61/339,273 filed Mar. 2, 2010; which further is a continuation-in-part of U.S. patent application Ser. No. 12/360,467 filed Jan. 27, 2009; and which further is a continuation-in-part of U.S. patent application Ser. No. 12/584,143 filed Sep. 1, 2009 which claims priority to U.S. Provisional Patent Application No. 61/094,595 filed Sep. 5, 2008.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to illumination devices and, more particularly, to controlling illumination devices.
[0004] 2. Description of Related Art
[0005] A wide variety of lighting control systems are currently commercially available for controlling a variety of lighting features from simple on/off switching to complex color adjustment and performance monitoring. Such systems also communicate according to a wide variety of protocols over various communication channels. As an example, a simple system could be just a triac dimmer and a single lamp. As another example, a complex system could be a hierarchical campus wide network. In such a complex system, up to 64 intelligent fluorescent lamp ballasts within a room or group of rooms could be wired together using the Digital Addressable Lighting Interface (DALI) standard, for instance, with an Ethernet enabled DALI controller, which then communicates with other DALI controllers and a computer server over Ethernet within each building. At the top layer of the hierarchy, the computer servers in different buildings within a campus could communicate over the Internet using Internet Protocol (IP).
[0006] Some lighting control systems use protocols that are somewhat specific to lighting, such as 0-10V, DMX512, DALI, and Dynalite, while others use protocols that target building automation in general, such as X10, LonWorks, C-Bus, and ZigBee. Still other lighting control systems use industry standard networking protocols such as Ethernet, Wi-Fi, and HomePlug. At the campus wide level with communication over the Internet, such complex lighting control systems can also use telecom networking protocols such as SONET and ATM. All theses standards and protocols communicate at different rates, using different modulation and packetizing schemes, over various communication channels. Such channels include powerline for X10 and HomePlug, RF for ZigBee and Wi-Fi, optical fiber for SONET, and dedicated wires for most of the others including 2 wire DC for 0-10V, twisted pair for DALI and others, and CAT5 for Ethernet.
[0007] The 0-10V standard was one of the earliest and simplest lighting control signaling system, which is still supported by many fluorescent ballasts produced by companies such as GE, Philips, and Sylvania. Such ballasts produce light from an attached fluorescent lamp that is proportional to the DC voltage input to the ballast through two wires. Although simple to understand and implement, each ballast must have a dedicated cable to the system controller, which can become very expensive and cumbersome in large installations. Additionally, such a lighting control system can only control light level and cannot extract information from the ballast, such as if a bulb has burned out.
[0008] The DMX512 stands for “Digital Multiplex with 512 pieces of information” and is a standard for digital communication commonly used in theaters and production studios. DMX512 communicates over shielded twisted pair cable using EIA-485 standard voltages levels with node connected together in a daisy chain manner. Data is sent one byte per packet at 250 kbaud in a manner similar to RS232. The DMX512 protocol is popular for stage lighting due to the robustness of its cable and the relatively long communication distances.
[0009] The DALI standard, which is becoming relatively popular for commercial lighting systems, is similar to DMX512 in that various lamps can be individually controlled using a relatively low data rate digital control bus, however, there are many differences ranging from the type of communication cable and interconnections to data format and messaging requirements. While DMX512 communicates uni-directionally over shielded twisted pair cable between two nodes, DALI communicates bi-directionally over un-shielded twisted pair that can be tapped by up to 64 devices. While all DMX512 data frame comprise one start bit, 8 data bits, and two stop bits, DALI has different sized frames for communication in the different directions with both acknowledge and data bytes in one direction and no acknowledge in the other direction.
[0010] Unlike DALI, DMX512, 0-10v, and other protocols developed specifically for lighting, X10 was developed for general home automation of which lighting is an important subset. A further substantial difference is that X10 typically communicates data over the power lines that are already connected to most devices. X10 devices typically communicate one bit of information around each zero crossing of a 50 or 60 Hz AC mains cycle, by coupling bursts of a high frequency signal onto the powerline. As such, the data rate is very low. To compensate, the protocol is very simple in which all packets consist of an 8 bit address and a 4 bit command. Since only 16 commands are possible, functionality is limited.
[0011] HomePlug is another protocol that uses the power line for communication, however, unlike X10, which was architected for home automation, HomePlug was designed to allow products communicate with each other and the Internet through existing home electrical wiring. A variety of versions of HomePlug have been released with data rates ranging from 10 to 200 Mbit/s. HomePlug achieves such data rates using adaptive modulation and complex error correction algorithms on over a thousand Orthogonal Frequency Division Multiplexed (OFDM) sub-carriers.
[0012] Data in a HomePlug network is typically communicated in Ethernet compatible packets, which comprise of a header with about 22 bytes, the payload with up to 1500 bytes, and a CRC code with 4 bytes, however, HomePlug also provides a variety of higher level services that provide, among other things, guaranteed delivery, fixed latency, quasi-error free service, and jitter control. As such, a HomePlug interface is much more complicated than is needed for simply lighting control.
[0013] Although communication over a power line is a good solution for some building networking applications, there are some drawbacks. For instance, there can be excessive attenuation between different phases of typically three phase systems, which can be overcome by active repeaters or sometimes with special capacitors. Additionally, signals can propagate through the power line between different buildings causing interference and security concerns. When appliances turn on and off significant noise is generated that can corrupt transmission. HomePlug physical layer interfaces have overcome some of such issues at the expense of complex analog and digital signal processing.
[0014] LonWorks is a building automation protocol that typically uses either twisted pair cable at 78 kbit/sec or the power line at a few kilobits per second for the communication channel. For communication over the power line, LonWorks uses dual carrier frequency operation in which messages are sent using one carrier frequency and, if a response is not received, the message is sent a second time using a second carrier frequency. More recent releases of the protocol allow IP data frames to be communicated across a LonWorks network, and a library of commands for a wide variety of appliances and functions have been and continue to be developed for a range of residential and commercial applications.
[0015] The C-Bus Protocol targets home automation systems as well as commercial lighting systems. Unlike the X10 protocol, C-Bus typically uses dedicated CAT5 cables and is considered by some to be more robust as a result. Ethernet also typically uses CAT5 cable for communicating between devices in a star topology with a router or switch at the center. Common data rates include 10, 100, and 1000 Mbit/sec, which are all deployed widely worldwide for computer networking. As mentioned previously, Ethernet data frames comprise a header of typically 22 bytes, a payload of up to 1500 bytes, and a CRC of four bytes. In many applications, the payload of an Ethernet frame is an Internet Protocol (IP) packet. Although overkill for simple lighting systems, Ethernet comprises the backbone of a variety of building lighting control networks, such as those from LumEnergi and others.
[0016] ZigBee comprises a group of high level communication protocols that typically use the IEEE 802.15.4-2003 standard for Wireless Personal Area Networks (WPANs) as the physical layer. As such, ZigBee typically uses small low power radios to communicate between appliances, light switches, consumer electronic, and other devices in a residence for instance. IEEE 802.15.4 uses either the 868 MHz, 915 MHz, or 2.4 GHz radio frequency bands. Data is direct-sequence spread spectrum coded and then Binary Phase Shift Key (BPSK) or Orthogonal Quadrature Phase Shift Key (OQPSK) modulated prior to transmission. Data is communicated in one of four different types of frames with variable data payload. Such frames include beacon frames, which specify a super-frame structure similar to that of HomePlug, data frames used for transfers of data, acknowledge frames used for confirming reception, and MAC command frame used for controlling the network. The SuperFrame structure allows certain devices guaranteed bandwidth and provides shared bandwidth for other devices. Many aspects of the network enable very low power communication with battery powered devices.
[0017] Wi-Fi or 802.11 is a very common wireless network for data communication between computers. A number of versions of the protocol including 802.11a, 802.11b, and 802.11g have been released over the years. The recent version, 802.11g, operates at the 2.4 GHz band and uses Orthogonal Frequency Division Multiplexing (OFDM) and typically achieves about 22 Mbit/sec average throughput. Similar to Ethernet, Wi-Fi frames comprise of a header, payload, and CRC. Similar to 802.15.4, Wi-Fi has a variety of different types of frames for communication management. In general, Internet Protocol (IP) and the associated Transport Control Protocol (TCP) run over Wi-Fi networks.
[0018] Although wireless protocols such as ZigBee and Wi-Fi do not need dedicated wires to communicate between devices, nor do they have the limitation previously mentioned associated with power line communication, such wireless networks can be limited by congestion in the increasingly crowded RF spectrum. Additionally, different countries in the world allocate spectrum differently which forces devices to sometimes operate in different frequency bands.
SUMMARY OF THE INVENTION
[0019] An alternative physical layer communication channel and associated network protocol for lighting control among other applications have been introduced that use modulated visible light traveling through free space to communicate data. According to such visible light communication (VLC) protocol, all devices synchronize to a frequency or phase of the AC mains for instance and produce gaps during which messages can be sent. At other times, lamps using LEDs or any other type of light source, simply produce illumination. During the gap times some number of bytes of data can be sent from one lamp to one or more other lamps that can comprise a complete message in itself, or such data can accumulate over any number of gaps to produce much larger messages.
[0020] Using visible light to communicate between lamps and other devices in a lighting system has many advantages over wired, wireless, and powerline communication networks such as those previously described. No dedicated wires are needed, which is important especially for installation in existing buildings. The visible light spectrum is unregulated globally and does not suffer from the congestion and interference common in RF wireless communication. Electrical noise on the powerline, from appliances turning on and off for instance, does not affect communication integrity as in powerline communication protocols. No expensive and complicated analog and digital signal processing is necessary to modulate and demodulate data as in many wireless and powerline protocols. The light source needed to transmit data is necessary anyway to provide illumination, and in the case that the light source is one or more LEDs, the LEDs can operate as the light detector as well. As such, the visible light communication protocol can be implemented in an LED lamp for virtually no additional cost.
[0021] A limitation of such a visible light communication protocol is that data cannot be communicated through walls between various rooms in a building. Another limitation is that, other than the remote controller, it is difficult to cost effectively control such a visible light communication network. The invention described herein, in various embodiments, provides solutions to overcome these limitations.
[0022] According to one embodiment, an electronic device is provided herein for controlling a lighting system. In certain exemplary embodiments, the electronic device is mounted to a wall in a room or held in a hand, for instance, and comprises a Human Machine Interface (HMI), such as a touch screen or a set of buttons (e.g., dedicated to specific lighting functions or programmable to perform a variety of functions) that are illuminated by a light source. In addition to illuminating the HMI, the light source also transmits messages through free space using visible light to one or more lamps in the room. For example, a HMI could comprise an LCD panel, which is illuminated by an LED backlight for displaying information about the controls or lighting system, and either an overlaid touch screen sensor or additional pushbuttons for entering information. Alternatively, the HMI could comprise just pushbuttons that are illuminated by some light source for use in the dark.
[0023] For a handheld electronic device (otherwise referred to herein as a wireless communication device), such as a smart phone or tablet computer, the display backlight could be modulated in a variety of ways including playing a video with alternating light and dark frames to produce light modulated with data. The ambient light sensor available on many handheld electronic devices could be used to receive data transmitted through free space using visible light. An alternative light source in many handheld electronic devices such as smart phones is the camera flash, which typically comprises one or more LEDs that can be modulated through software to transmit data through free space using visible light.
[0024] As another example, the light source in an electronic device that is mounted to a wall, for instance, can be synchronized to a frequency or phase of the AC mains, produce communication gaps that are synchronous to the communication gaps used by lamps in the room, and transmit data to the lamps in response to input from a user. Additionally, such an electronic device can have a light detector for receiving information from the lamps that is transmitted through free space using visible light. If the light source is one or more LEDs, then the LEDs can be both the light source and the light detector. In a further embodiment, the light produced by a light source in the electronic device is perceived as unchanging by a user independent of whether data is being transmitted or not. This is accomplished, for instance, by producing a small amount of light continuously when data is not being transmitted and by turning this small amount of light off before or after data is transmitted at high brightness for instance. In this exemplary embodiment, control circuitry within the electronic device is configured to produce commands in response to input directly from a user.
[0025] In certain exemplary embodiments, an electronic device comprising an HMI with a light source and a light detector also comprises circuitry to interface to any type of data communication network typically used for lighting or building control information. Such data communication network could communicate over dedicated wires (e.g., Ethernet, DALI, DMX512, and others), the power line (e.g., X10, HomePlug, and others), RF wireless (e.g., ZigBee, Wi-Fi, and others), or any other communication channel including for instance fiber optic cable and wireless infra-red. Such data communication network could interface for instance to a central building controller over Ethernet or DALI, or could interface for instance to a wireless communication device (such as a smartphone) over Wi-Fi, Bluetooth, IRDA, or any other data communication protocol supported by such wireless communication device. In some instances, the electronic device could comprise interfaces to multiple data communication networks, such as Ethernet and Wi-Fi, to support lighting control systems with mixed environments.
[0026] In an electronic device comprising an HMI that can communicate through free space using visible light, and interfaces to one or more data communication networks, control circuitry would receive input directly from the user through the HMI, data received from such data communication networks, or data received optically through free space. Such control circuitry in response to such input or data would produce commands encoded and transmitted according to a visible light communication protocol.
[0027] In certain exemplary embodiments, a lamp comprises a light source for illuminating an area and transmitting data through free space using visible light, a light detector for receiving data transmitted through free space using visible light, and an interface to one or more other types of data communication networks that carry lighting control information. If one or more LEDs can operate as the light source, then such LEDs could also be operable as both the light source and the light detector. The data communication network could communicate with the lamp over any type of communication channel and communication protocol. The lamp could be a lamp in a ceiling, for instance. In such a lamp, control circuitry receives input from one or more such data communication network or networks and produces commands encoded and transmitted according to a visible light communication protocol such as that described in the one or more priority applications listed herein.
DESCRIPTION OF THE DRAWINGS
[0028] The present invention may be better understood, and its numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings.
[0029] FIG. 1 is an exemplary block diagram of a lighting control system comprising a plurality of lamps, an electronic device and optional wireless communication device.
[0030] FIG. 2 is an exemplary block diagram of a lamp that communicates with an electronic device and/or other lamps through free space using visible light.
[0031] FIG. 3 is an exemplary block diagram of a lamp that communicates with other lamps through free space using visible light and with a network and other controlling devices through a Wi-Fi interface.
[0032] FIG. 4 is an exemplary diagram for the structure of a Wi-Fi data communication packet.
[0033] FIG. 5 is an exemplary diagram for a packet communicated through free space using visible light.
[0034] FIG. 6 is an exemplary drawing of an electronic device with an HMI, wherein the electronic device controls a lighting system by communicating with lamps through free space with visible light and communicating with a network and other controlling devices through Wi-Fi and Ethernet interfaces.
[0035] FIG. 7 is an exemplary block diagram of an electronic device with an HMI, wherein the electronic device controls a lighting system by communicating with lamps through free space with visible light and communicating with a network and other controlling devices through Wi-Fi and Ethernet interfaces.
[0036] FIG. 8 is an exemplary timing diagram for communicating between an HMI and lamps through free space using visible light.
[0037] The use of the same reference symbols in different drawings indicates similar or identical items. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.
DETAILED DESCRIPTION
[0038] Turning now to the drawings, FIG. 1 is one example of a building lighting system 10 that comprises building controller 11 configured for controlling the lighting system and a network 12 that connects room1 13 , room2 14 , and roomN 15 to building controller 11 . The lighting system 10 shown in FIG. 1 further includes an electronic device 16 , or possibly a lamp 22 , which communicates with the network 12 . The designation room1 through roomN represents any number of rooms in a building or even multiple buildings to one of more central controllers represented by building controller 11 . Within any particular room, a plurality of lamps (e.g., lamps 17 , 18 , and 19 within room1, or lamps 22 , 23 and 24 within room2) may communicate with each other and with an electronic device 16 through modulated visible light shown in FIG. 1 with bi-directional arrows.
[0039] In example room1 13 , electronic device 16 interfaces between network 12 , lamps 17 , 18 , and 19 , and optionally wireless communication device 20 . Wireless communication device 20 may or may not be part of building lighting system 10 , but if included, can be any type of mobile device including but not limited to mobile phones, smart phones, personal digital assistants (PDA), and mobile computers such as netbooks, notebooks, and laptops. Wireless communication device 20 could also be a stationary device, such as a desktop computer. In some embodiments, wireless communication device 20 may communicate with electronic device 16 using any radio or infra-red frequency wireless communication protocol including, but not limited to, Zigbee, Wi-Fi, and Bluetooth. In some embodiments, wireless communication device 20 may be configured for controlling the lighting system, similar to electronic device 16 , and may be considered to be a hand held electronic device.
[0040] Network 12 typically might communicate according to the wired DALI or Ethernet standards, or the wireless ZigBee or Wi-Fi standards, but could communicate according to any data communication protocol using wired, wireless, powerline, fiber optic, or any other type of communication channels. Network 12 and optional wireless communication device 20 can communicate according to the same or different wireless protocols, or can communicate over different protocols using different wired or wireless communication channels.
[0041] Electronic device 16 represents any electronic device that provides an interface between lamps 17 , 18 and 19 and network 12 , and that also provides a human machine interface (HMI) 21 . HMI 21 is configured to receive input from a user, which is typically used, but not limited to, local control of lamps 17 , 18 , and 19 in room1 13 , for instance. In one embodiment, electronic device 16 could be a device mounted on a wall within room1 13 that enables a user to control the lighting within room1 13 independent of and/or overriding commands from building controller 11 . Electronic device 16 could be a device about the size of a conventional light switch or a ganged light switch. In one example, electronic device 16 could be implemented with an HMI 21 , such as a display and touch screen that enables a user to select lighting functions from a menu or nested menus for instance. Electronic device 16 also, for instance, could be implemented with an HMI 21 , such as a set of buttons that are dedicated to particular functions, such as on/off, dimming, color, timing, and other functions such as those described in the one or more priority application listed herein.
[0042] In the example lighting system of FIG. 1 , electronic device 16 communicates with lamps 17 , 18 , and 19 through modulated visible light. According to one embodiment, electronic device 16 could comprise a dedicated light source, which is configured to provide illumination and to transmit data optically through free space using visible light, and optionally an additional light detector, which is configured to receive data transmitted optically through free space using visible light. According to another embodiment, the dedicated light source may be used to both illuminate the HMI 21 and to communicate modulated visible light uni-directionally or bi-directionally with lamps 17 , 18 , and 19 in the example room1 13 of FIG. 1 .
[0043] In order for the HMI 21 to be visible in the dark, for instance, the electronic device typically comprises a backlight (or a light source positioned behind the HMI) that illuminates the HMI (e.g., various push buttons or an LCD display with an overlaid touch screen sensor) from behind. Many possible HMIs are possible with the commonality that a light source is typically necessary for a user to see in at least a dark environment. Such a light source typically will be an LED or array of LEDs, but could comprise any type of light source including, for instance, Cold Cathode Fluorescent lamps (CCFL). If the light source is a CCFL or, for instance, a white LED with a phosphor coating, preferentially the electronic device also comprises an additional photo-detector.
[0044] According to one embodiment of the invention, the light emitted from the backlight of the HMI is modulated in such a way that one or more of lamps 17 , 18 , and 19 can detect the data represented by such modulation. In some embodiments, electronic device 16 can also receive data sent by lamps 17 , 18 , or 19 , e.g., through the additional photo-detector, or through the backlight. For example, if the backlight comprises one or more LEDs for illumination and data transmission, and preferentially mono-chromatic LEDs such as red, green, and blue, the LEDs used for illumination and data transmission may also be used to receive data sent by lamps 17 , 18 , or 19 .
[0045] According to another embodiment of the invention, wireless communication device 20 , which could be any type of computing device with a backlit display such as a smart phone, PDA, or a tablet, netbook, notebook, or desktop computer, may communicate directly with electronic device 16 or with lamps 17 , 18 , and 19 through free space using visible light. For example, wireless communication device 20 may produce commands in response to input received directly from a user, and may transmit such commands to the electronic device 16 or directly to the lamps 17 , 18 and 19 using visible light. As with electronic device 16 , the backlight for the display of the wireless communication device 20 can be modulated to transmit data or commands optically to the electronic device 16 or directly to lamps 17 , 18 , and 19 . This can be accomplished in various ways including, but not limited to, playing a video with alternating light and dark frames producing the transmitted data. The ambient light sensor available on many wireless communication devices can also be used as a light sensor to receive data. Alternatively, the camera flash, which typically comprises one or more LEDs on a smart phone, for instance, can also be modulated through software to transmit data to electronic device 16 or to lamps 17 , 18 , and 19 in the example of FIG. 1 .
[0046] According to another embodiment, a lamp may be used to interface with the network 12 instead of an electronic device. As represented by room2 14 , for instance, lamp 22 provides an interface between the lamps 22 , 23 , and 24 within room2 14 and network 12 . As such, lamp 22 comprises a network interface, which is capable of communicating with network 12 according to any protocol using any communication channel including, but not limited to, RF wireless, wired, fiber optic, or power line. In this example room2 14 , lamp 22 further comprises a light source for illumination and data transmission, and a light detector for receiving data from lamps 23 and 24 . In one embodiment of the invention, if the light source is one or more LEDs, then such LEDs can also operate as the light detector depending on when data is to be sent or received.
[0047] As in example room1 13 and wireless communication device 20 , wireless communication device 25 in room2 14 , for instance, can locally control lamps 22 , 23 , and 24 by overriding commands from building controller 11 or can implement any functionality supported by lighting system 10 . In this example room2 14 , wireless communication device 25 communicates with lamp 22 , which also provides the interface to network 12 . As such, according to one embodiment of the invention, lamp 22 further comprises a wireless interface compatible with wireless (RF, infra-red, etc) communication device 25 and an interface compatible with network 12 .
[0048] Within the example room1 13 and room2 14 , lamps 17 , 18 , and 19 , and lamps 22 , 23 , and 24 respectively communicate between each other using modulated visible light. When observed by the human eye, although the light is visible, the modulation of the light is typically not discernable and is typically perceived as constant and unchanging light. The maximum distance between any two lamps, for instance lamps 17 and 18 , is determined by the brightness and directionality of the data transmitting lamp and the light detection sensitivity of the data receiving lamp. In the example room1 13 , lamps 17 and 18 are positioned within such maximum communication distance, and lamps 17 and 19 for instance are positioned beyond such maximum communication distance. According to another embodiment of the invention, lamp 18 in the example room1 13 relays messages sent through modulated visible light between lamps 17 and 19 to enable communication between large numbers of lamps that are large distances apart.
[0049] According to the invention, lamps that relay commands first receive data on a light detector and forward such input to control circuitry that regenerates commands in response to such input. For instance, commands can be directed from lamp 17 to lamp 19 only, while lamp 18 simply receives and retransmits such commands along a dedicated path as in the Internet. Alternatively, messages from an example lamp 17 can be broadcast to all lamps in which lamp 18 for instance responds to such broadcast command and also retransmits such command to lamp 19 for instance. As such, commands can be sent through a network of lamps as broadcast messages or through dedicated or ad-hoc paths between particular lamps or groups of lamps. Ad-hoc paths are well known to those practicing in the field of mesh networking, which is commonly used in Zigbee wireless networks for instance.
[0050] FIG. 1 is just one example of many possible lighting control systems 10 , which could comprise any number of buildings, rooms within each building, and lamps within each room, hallway, entryway, etc. Additionally, lighting control system 10 may comprise of any number of building controllers and any type or multi-types of networks between rooms. The networks 12 between rooms can communicate according to any type of protocol including standards such as Ethernet, DALI, Wi-Fi, and others that use wired, RF, power line, fiber optic, or any other type of data communication channel.
[0051] The embodiments of the invention illustrated by this example FIG. 1 include, but are not limited to, the following devices:
a. electronic device 16 that produces commands in response to input received directly from a user through an HMI 21 , from a lighting control network 12 , or from a wireless communication device 20 , and transmits such commands using the same light source that is used to illuminate the HMI 21 of the electronic device 16 ; b. wireless communication device 20 that produces commands in response to input directly from a user and transmits such commands to the electronic device 16 or directly to the lamps 17 , 18 or 19 using the backlight or the flash of the wireless communication device 20 ; c. lamp 22 that produces commands in response to input received from a lighting control network 12 or a wireless communication device 25 and transmits such commands to lamps 23 and 24 using the same light source that is used for illumination; d. lamp 17 that produces commands in response to input received from another lamp 18 or 19 or an electronic device 16 and detected by the light sensor, and transmits such commands using the same light source that is used for illumination.
[0056] Preferentially, lamps 17 , 18 , 19 , 22 , 23 , and 24 and optionally electronic device 16 communicate between each other in synchronization with the AC mains 31 , as described in one or more priority applications listed herein; however, such devices could communicate according to any communication protocol that uses visible light traveling through free space. Such communication can be between devices that are in or out of synchronization and according to any modulation technique, data rate, or distance. Likewise, any routing or mesh networking protocol can be implemented using such devices that receive and retransmit commands optically through free space. As noted herein, the term “free space” refers to communication within space, but not confined to, for example, an optical fiber. Thus, transfer of commands occurs optically, but not constrained within an optical fiber or any other type of waveguide device, yet is free and able to travel optically in any non-obstructed direction. The example of a building lighting system 10 does not limit the embodiment to a single building, but can be among several buildings or within a portion of the building. Moreover, each room shown in the lighting system 10 is configured according to one example if, for example, there are several rooms controlled by a lighting system. If the system controls only a single room, then the example in FIG. 1 would apply to different sub-regions within that room, each having a different interface to a network. Likewise, each room or sub-regions of a room can be controlled according to that shown in room1 13 , room2 14 , or both.
[0057] Thus, the lighting system can be controlled with an electronic device 16 that comprises a HMI 21 and provides an interface between lamps 17 , 18 , 19 and network 12 . Alternatively, the lighting system can be controlled with a wireless communication device, e.g., device 25 , and interface to the network 12 can be achieved solely with a light source (e.g., lamp 22 ), which can also function as a light detector. In this case, the HMI can be achieved by a wireless communication device (e.g., device 25 ) that need not be configured between the lamps 22 , 23 , and 24 and the network 12 .
[0058] Accordingly, an electronic device is provided herein having both a light source and a light detector, as well as control circuitry, which is configured to produce commands for controlling the lighting system in response to received input and/or data. The electronic device can further comprise an HMI configured to receive input from a user, and/or a network interface configured to receive data from a network, depending on the configuration shown in the examples of FIG. 1 . Various embodiments of lamps are also provided herein having a light source, a light detector and control circuitry that produces commands transmitted by the light source in response to commands received through the light detector. In some embodiments, a lamp may be configured to produce commands in response to input received from a network 12 or a wireless communication device 25 and to transmit such commands to other lamps using the same light source that is used for illumination.
[0059] FIG. 2 is one example of a block diagram of a lamp 30 comprising a light source that is configured to provide illumination and transmit data optically through free space, a light detector that is configured to receive data transmitted optically through free space, and a control circuit that produces commands transmitted by the light source in response to commands received through the light detector. According to one embodiment, LEDs 36 may be configured at different times as both the light source and the light detector. Example lamps 17 , 18 , 19 , 23 or 24 could comprise the circuitry represented by this example FIG. 2 . As such, in addition to providing general illumination, a lamp comprising such control circuitry can receive messages sent via modulated visible light (e.g., from electronic device 16 , wireless communication device 20 or 25 , or another lamp) and can retransmit such information according to any pre-determined fixed routing or any ad-hoc mesh networking protocols for instance.
[0060] As shown in FIG. 2 , lamp 30 connects to the AC mains 31 that provides power and synchronization in this example. Power supply 32 converts AC power to DC power that provides current to LEDs 36 and voltage to the remaining circuitry in lamp 30 . Timing 33 typically comprises a phase locked loop (PLL) that locks to the AC mains 31 frequency and/or phase, and provides timing information to visible light communication (VLC) network controller 34 and physical layer interface (PLI) 35 . Since the example electronic device 16 and lamps 17 , 18 , 19 , 22 , 23 , and 24 ( FIG. 1 ) are all coupled and thus synchronized to the same AC mains 31 , the timing of the VLC network controllers 34 and PLIs 35 in all such example devices is substantially the same, which simplifies data communication as described in one or more priority applications listed herein.
[0061] PLI 35 typically comprises an LED driver circuit (not shown) that produces a substantially DC current to produce illumination from LEDs 36 and modulated current to transmit data from LEDs 36 . Such substantially AC and DC currents can be combined in many different ways to produce both illumination and transmit data using the same light source. Periodic time slots can be produced in synchronization with the AC mains 31 during which the example DC current is turned off and the example AC current is turned on during gaps in which data is transmitted.
[0062] PLI 35 also typically comprises a receiver circuit (not shown) that in this example FIG. 2 detects photo-current induced in LEDs 36 while receiving data transmitted using visible light through free space. Such receiver typically converts such photo-current to voltage, which is then compared to a reference voltage to determine a sequence of ones and zeros sent by the transmitting device. The details of one example PLI 35 are described in one or more priority applications listed herein.
[0063] VLC network controller 34 interfaces with PLI 35 and memory 37 to receive commands transmitted using visible light through free space, to implement the necessary control circuit functionality of lamp 30 , and in some cases, re-transmit commands using LEDs 36 that were previously received by LEDs 36 during gap times. Commands received by the light detector, in this case LEDs 36 , can be stored in memory 37 and further processed. Commands that target lamp 30 can be interpreted by VLC network controller 34 and processed locally. For instance, the brightness or color of LEDs 36 can be adjusted by adjusting the substantially DC current applied to LEDs 36 by the driver function within PLI 35 . Commands that target other or additional lamps can be stored in memory 37 and re-transmitted by PLI 35 and LEDs 36 during subsequent gap times for instance. Such commands can be routed through a pre-determined path, through an ad-hoc mesh network, or broadcast to all electronic devices for instance. VLC network controller 34 may be configured to communicate such commands according to a visible light communication protocol.
[0064] In this example FIG. 2 , timing 33 can not only synchronize all electronic devices and lamps 30 in the network, but can also provide timing to power supply 32 to minimize noise coupling into PLI 35 . As such, FIG. 2 is just one example of many possible lamps 30 that receive commands communicated through free space using a light detector and re-transmit such commands to other electronic devices or lamps using visible light. The preferential visible light communication protocol is described in one or more priority applications listed herein, however, any visible light communication protocol and multiplexing scheme between illumination and data communication are possible. Additionally, lamp 30 could have a variety of block diagrams different from this example FIG. 2 . For instance, lamp 30 could be DC or solar powered for instance. Likewise, any type of light source is possible including, but not limited to, fluorescent tubes, compact fluorescent lights, incandescent light, etc. In particular, lamp 30 could comprise a light detector, such as a silicon photo-diode in addition to the light source, which in this example FIG. 2 is LEDs 36 .
[0065] FIG. 3 is one example block diagram of a lamp 40 (e.g., lamp 22 in FIG. 1 ) that can transmit and receive data communicated using visible light through free space, and can also communicate according to the wireless 802.11 protocol with building controller 11 and wireless communication devices 20 and 25 . As in lamp 30 , lamp 40 comprises LEDs 36 , PLI 35 , VLC Network Controller 34 , memory 37 , and timing 33 . Power supply 41 may be slightly different from power supply 32 due to the additional load provided by the additional processor 42 and Wi-Fi interface 43 .
[0066] In this example lamp 40 , LEDs 36 operate as both the light source and the light detector for transmitting and receiving data using visible light communicated through free space. LEDs 36 also provide illumination. Wireless 802.11 interface 43 can receive messages from wireless communication devices (e.g., a smart phone) 20 and 25 , or from building controller 11 , and can forward such messages to processor 42 , which can implement the control circuitry functionality necessary to interpret or translate such messages to commands that can be transmitted through free space using visible light (e.g., using LEDs 36 as the light source). Likewise, commands transmitted optically through free space can be received by LEDs 36 operating as light detectors, interpreted or translated by processor 42 , and transmitted by Wi-Fi interface 43 back to wireless communication devices 20 and 25 or building controller 11 .
[0067] Whether or not a lamp includes a processor and separate Wi-Fi interface, as shown in FIG. 3 , it is appreciated that the lamp operates as a light source and a light detector via one or more LEDs to which it controls. When a separate processor and Wi-Fi interface are not included, as in the embodiment of FIG. 2 , the VLC network 34 of the lamp 30 provides the control circuitry through the PLI 35 to the light source and light detector dual purpose function of the LEDs 36 . The controllable LEDs can control other LEDs within optical range, both within a bank of LEDs 36 or external to the bank of LEDs as shown by the bi-directional arrows of FIGS. 2 and 3 .
[0068] FIG. 4 illustrates the typical data frame format 50 for Wi-Fi, which comprises up to thirty bytes for header 60 , zero to two thousand three hundred twelve (2312) bytes for data 58 , and four bytes for frame check sequence (FCS) 59 . Header 60 typically comprises two bytes for frame control 51 , two bytes for the duration ID 52 , six bytes for source address 53 , six bytes for destination address 54 , six bytes for receiver address 55 , two bytes for sequence control 56 , and six bytes for transmitter address 57 . Typically in a Wi-Fi network, data 58 comprises packets that conform to the Internet Protocol (IP), which comprise up to an additional 20 bytes of header.
[0069] FIG. 5 illustrates a possible data frame format, which is generally compatible with the ZigBee wireless RF protocol, for communicating with visible light. The data frame format shown in FIG. 5 comprises a Physical Protocol Data Unit (PPDU) 70 , which further comprises four bytes for preamble sequence 66 , one byte for start of frame delimiter 67 , one byte for frame length 68 , and up to 128 bytes for Mac Protocol Data Unit (MPDU) 69 . MPDU 69 comprises two bytes for frame control 61 , one byte for data sequence number 62 , four to twenty bytes for address information 63 , N bytes for data 64 , and four bytes for Frame Check Sequence (FCS) 65 .
[0070] In the example lamp 40 illustrated in FIG. 3 , Wi-Fi interface 43 can forward received data frames conforming to the example Wi-Fi protocol illustrated in FIG. 4 to processor 42 . Processor 42 interprets such data frames and creates data frames conforming to the example visible light communication protocol illustrated in FIG. 5 . Processor 42 inputs such data frames to VLC network controller 34 for transmission through PLI 35 and LEDs 36 . Likewise, data frames input to VLC network controller 34 through LEDs 36 and PLI 35 can be processed and transmitted through PLI 35 and LEDs 36 or forwarded to processor 42 , which can interpret such data frames, create data frames conforming to the example Wi-Fi protocol and forward such data frames to Wi-Fi interface 43 for transmission over such Wi-Fi network.
[0071] FIG. 3 is just one of many possible block diagrams for lamp 40 . For instance, instead of the LEDs 36 shown in FIG. 3 , the light source could be a fluorescent bulb or any other type of light source. Lamp 40 could also comprise a photo-detector, such as a silicon photodiode, instead of using LEDs 36 as both the light source and light detector. Lamp 40 does not need to be synchronized to the AC mains and comprise timing block 33 . Many other means of synchronization are possible and communication even without synchronization is possible. Lamp 40 could be battery or solar powered, for instance, and as such would have a different or no power supply 41 . VLC network controller 34 and PLI 35 in this example implement the data frame format illustrated in FIG. 5 , but could implement any type of communication protocol using visible light. For instance, the protocol described uses substantially the same frame format as ZigBee, however, any frame format including substantially simpler versions with smaller headers are possible.
[0072] Wi-Fi interface 43 is just one example of many different network interfaces using many different types of communication channels that are possible. It is also possible to have multiple interfaces to different networks. Some other network examples include X10, DMX512, DALI, Ethernet, ZigBee, HomePlug, LonWorks, C-Bus, Dynalite, Bluetooth, and even SONET and ATM. A typical configuration for lamp 22 in FIG. 1 could include a Wi-Fi interface 43 for communicating with a smart phone for instance for local control, and an Ethernet interface (not shown) for communicating with a building controller 11 .
[0073] FIG. 6 illustrates one embodiment of the electronic device 16 from FIG. 1 that interfaces to network 12 , wireless communication device 20 , and lamps 17 , 18 and 19 . In this example FIG. 6 , a user can also control lamps 17 , 18 , and 19 within room1 13 , and potentially the entire lighting system 10 , by pushing regions of touch screen 80 that overlay menu 84 that is an image produced by LCD 81 and illuminated by backlight 82 . The example menu 84 provides various buttons to turn lights on and off (ON/OFF), adjust brightness (DIM), change color (COLOR), set the timer (TIMER), adjust the ambient light sensor (AMB), and access advanced programming functions (PROG). In this example FIG. 6 , electronic device 16 is powered by the AC mains 31 and is contained within housing 83 . The HMI in FIG. 6 is provided by the touch screen 80 and LCD 81 .
[0074] Electronic device 16 communicates with building controller 11 through network 12 according to any one of many different data communication protocols over any of a variety communication channels including but not limited to CAT5 or twisted pair cable, RF wireless, powerline or fiber optics. Although it need not communicate with device 20 , electronic device 16 can also optionally communicate with wireless communication device 20 (which could be a smart phone) using any one of many different RF, infrared, or other wireless communication protocols, including but not limited to Wi-Fi, ZigBee, Bluetooth, IRDA, or others. According to one embodiment of the invention, electronic device 16 communicates with lamps 17 , 18 , or 19 through free space using modulated visible light that also provides illumination for electronic device 16 .
[0075] FIG. 7 is an example functional block diagram of the electronic device 16 that comprises a touch screen 80 , LCD 81 , backlight 82 , and housing 83 , as shown in FIG. 6 . Housing 83 can comprise the same timing 33 , memory 37 , VLC network controller 34 , PLI 35 and Wi-Fi interface 43 as illustrated in FIG. 3 , and can also comprise Ethernet interface 91 , touch screen controller 93 , graphic controller 94 , and processor 92 . LEDs 36 in the examples of FIG. 6 and FIG. 7 reside in backlight 82 and produce illumination for LCD 81 , and transmit data through free space using visible light. Additionally, LEDs 36 (which in the example of FIG. 7 could be red LEDs) can also operate as light detectors for receiving data transmitted through free space using visible light.
[0076] In this example FIG. 7 , electronic device 16 interfaces with building controller 11 according to the Ethernet protocol, which typically uses CAT5 cable as the communication channel. Messages received by Ethernet interface 91 can be forwarded to processor 92 , which can implement the control circuitry necessary to interpret or translate such messages to commands that can be transmitted through free space using visible light with LEDs 36 as the light source. As in FIG. 3 , messages received through Wi-Fi interface 43 can also be forwarded to processor 92 for interpretation and translation to commands that can be transmitted through free space using visible light with LEDs 36 as the light source.
[0077] In this example FIG. 7 , commands transmitted optically through free space can also be received by LEDs 36 operating as light detectors, interpreted or translated by processor 92 , and transmitted by Wi-Fi interface 43 back to wireless communication devices 20 or 25 , or transmitted by Ethernet interface 91 to building controller 11 . Likewise, processor 92 can route messages from any of Ethernet interface 91 , Wi-Fi interface 43 , and VLC network controller 34 to any other such network interface.
[0078] The protocol for communicating through free space using visible light can be the same as, or different from, the protocol described in one or more priority applications listed herein. In this example FIG. 7 , LEDs 36 can be configured to continuously provide illumination and communicate for instance with lamps 17 , 18 , or 19 , building controller 11 , or wireless communication device 20 at any time. As another possibility, LEDs 36 could typically be turned off and electronic device 16 could be in a low power state until a user first touches touch screen 80 , after which electronic device 16 powers up, illuminates LEDs 36 , and enables communication.
[0079] FIG. 6 and FIG. 7 are just examples of many possible diagrams for an electronic device 16 comprising an HMI 21 . Although FIGS. 6 and 7 illustrate the HMI 21 of the electronic device 16 as including a touch screen 80 and LCD 81 , the HMI could have any one of many other possible mechanical forms that do not necessarily include touch screen 80 or LCD 81 . For example, HMI 21 could comprise mechanical buttons that are illuminated from in front, behind, above, or below. As a further example, HMI 21 could comprise an Organic LED (OLED) display instead of an LCD. Backlight 82 can be any type of light source positioned in any manner to provide illumination for HMI 21 , which may have a dedicated light detector (such as a silicon photodiode) or use LEDs 36 for both emitting and detecting light. If HMI 21 comprises an OLED or any other type of active matrix display, such light source could be such active matrix display. Likewise, an OLED display could be the detector as well.
[0080] Electronic device 16 could be battery or solar powered, or powered in any other way instead of being powered by AC mains 31 . Electronic device 16 could be synchronized to lamps 17 , 18 , and 19 through any one of a number means, or not at all. Electronic device 16 could be a mobile computing device such as a smart phone, PDA, or netbook, notebook, or laptop computer, or a stationary computing device such as a desktop computer or even a television.
[0081] Menu 84 and the associated functionality described herein is just one possibility. Any number of different menus with totally different functionality is possible. If HMI 21 does not comprise some sort of display, then menu 84 may be replaced by pushbuttons for instance.
[0082] The block diagram for the electronic device 16 illustrated in FIG. 7 is just one of many possible examples. For instance, the light source could be a CCFL or even a CFL instead of the LEDs 36 . The electronic device 16 could also comprise an additional photodetector. Memory 37 could be a part of processor 92 . Other than the Wi-Fi and Ethernet interfaces illustrated, any type of network interface is possible to communicate with building controller 11 , network 12 , or wireless communication device 20 . Any number of network interfaces is also possible, including none. For instance, a smart phone could communicate directly with lamps 17 , 18 , and 19 by modulating the backlight or the camera flash, and as such, would not need a Wi-Fi interface 43 or Ethernet interface 91 . Ambient light sensors could be used to receive data transmitted optically.
[0083] FIG. 8 is an example timing diagram for transmitting data optically from electronic device 16 in a way that minimizes or eliminates flicker. The current through LEDs 36 is typically I1 103 , which should produce sufficient light to see menu 84 . As described in one or more priority applications listed herein, the current supplied to the LEDs 36 is periodically reduced from I1 103 to I0 102 to produce communication gaps 100 and 101 in synchronization preferentially with the AC mains 31 . As noted in the priority applications, the communication gaps are produced at regular, periodic intervals of each cycle of the AC mains, and the time duration of said communication gaps may be less than one quarter of each cycle of the AC mains. During gaps 100 when data is not being transmitted, the current through LEDs 36 is reduced to I0 102 , which could be a low level close to or equal to zero. During gaps 101 when data is being transmitted, the current through LEDs 36 is modulated between I0 102 and I2 104 , which is higher than I0 102 , so that the LEDs 36 emit light at two different output levels. I2 104 is preferentially, but not necessarily, the highest current LEDs 36 can tolerate in order to produce the most light to communicate the maximum distance. Any data modulation technique is possible including but not limited to Non-Return to Zero (NRZ) and Bi-phase.
[0084] To minimize possible flicker produced by gaps 101 during which data is transmitted at high brightness, during time 105 preceding gap 101 , as shown in FIG. 8 , or after gap 101 (not shown), the current through LEDs 36 is reduced from I1 103 to I0 102 , such that the average brightness of light produced by LEDs 36 is the same whether or not data is transmitted during the gap times.
[0085] FIG. 8 is just one of many possible examples of a timing diagram for transmitting data optically from electronic device 16 . For instance, communication gaps could occur at a faster or slower rate than the AC mains 31 , at rates totally unrelated to the AC mains 31 , or not at all. As an example, a video could be played on a smart phone that modulates the backlight or the light from an active display, such as an OLED, with light and dark frames in the video. The light from the electronic device could also be allowed to flicker for instance and as such could have a significantly different timing diagram from FIG. 8 .
[0086] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown and described by way of example. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed.
|
Intelligent illumination device are disclosed that use components in an LED light to perform one or more of a wide variety of desirable lighting functions for very low cost. The LEDs that produce light can be periodically turned off momentarily, for example, for a duration that the human eye cannot perceive, in order for the light to receive commands optically. The optically transmitted commands can be sent to the light, for example, using a remove control device. The illumination device can use the LEDs that are currently off to receive the data and then configure the light accordingly, or to measure light. Such light can be ambient light for a photosensor function, or light from other LEDs in the illumination device to adjust the color mix.
| 8
|
GOVERNMENT CONTRACT
The present invention was conceived and developed in performance of employment for the Department of the Army of the U.S. Government. All rights in the invention have vested in the U.S. Government.
FIELD OF THE INVENTION
This invention relates to electronic detection devices of the type used to sense the proximity of vehicles and more particularly, to antitank or other type anti-vehicle land mine simulation devices.
DESCRIPTION OF THE PRIOR ART
Proximity detectors have been used for many years and have been built in many designs. Such designs include mechanical trip-detectors, motion detectors, magnetic flux disruption detectors, and microwave detectors.
Generally a comparator or other signal level sensor is used to initiate a signal in response to a predefined "detection parameter". This signal then operates an alarm or a device, such as an electric door opener.
It is important to develop a casualty assessing proximity or other position detector to simulate an anti-vehicle land mine. No such type devices are known today. Such a device would simulate, as closely as possible, the size, structure and operation (reaction without an explosion) of a land mine. An electronic signal is substituted for any explosion.
OBJECTS OF THE INVENTION
An object of the present invention is to provide a land mine simulation system.
A second object of this invention is to provide such a system which includes for simulated land mine detonation and an electronic simulation of the effects of the explosive discharge of a land mine to duplicate the detonation operation of an actual land mine and thereafter electronically react to the simulated detonation.
A further object of this invention is to provide such a system with a casualty assessing subsystem wherein the casualty effects of simulated detonation are electronically assessed.
SUMMARY OF THE INVENTION
The objects of this invention are realized in a casualty assessing, mine effects simulator system.
A ground/land implantation device has a cylinder containing a low power level transmitter which forms a simulation land mine. A tilt rod type fuse and a pressure fuse activating device, a battery, a tilt switch and a logic card are all included in this device.
Logic gates allow the device to activate only one time per arming cycle regardless of the number of encounters.
The mine simulation device transmits one of two electronic signals when activated. A first signal occurs when the tilt rod is activated. This triggers the transmission of a low power signal which is received by a receiver unit in place on a vehicle. This reception triggers logic circuitry within the vehicle receiver unit to activate audio and visual signals. These signals can vary according to the type vehicle upon which the receiver subsystem device is mounted.
The activation of the tilt rod is classified by the system diagnostic and recording devices as a total "kill" of the vehicle. The receiver circuitry will pause and then transmit an alarm signal, to an on board training device processor.
If the pressure fuse in the simulation land mine is activated, it overrides the tilt rod fuse and creates a second signal which indicates a "mobility kill". The total kill (K-kill) and mobility kill (M-kill) provide different programmably predetermined events for training realism. These events can range from energizing the electrical horn system of the vehicle to causing the activation of a smoke grenade. Additionally, the vehicle receiver has the capability of an inter-face with a MILES system (multiple integrated laser engagement system).
The ground/land buried device is relocatable, reusable and programmable to operate as any of a variety of friendly or any antitank mine devices. It simulates live mines and is usable in providing training in mine deployment and mine breaching activities without threat of actual casualties.
DESCRIPTION OF THE DRAWINGS
The features operation and advantages of the present invention will be better understood from a reading of the following invention in which like numerals refer to like elements and in which:
FIG. 1 is a perspective view of an armor-class vehicle approaching a simulation mine of the present invention;
FIG. 2 is a side view cross-section of a tilt rod/pressure switch type simulation mine;
FIG. 2A is a detail of the construction of an illustrative tilt switch;
FIG. 3 is a block diagram of the mine effects simulation of the present invention;
FIG. 4 is a schematic circuit diagram of the mine core transmitter and associated circuitry.
FIG. 5 is a schematic circuit diagram of the receiver and associated circuitry.
FIGS. 6A, 6B and 6C are a schematic circuit diagram of the decoding/processing/conditioning circuit of the system.
FIG. 7 is a schematic circuit diagram of the relay that activates the smoke grenade and the Hoffman device.
FIG. 8 is a schematic circuit diagram of the voltage regulators used to power the circuitry.
FIG. 9 is a schematic diagram showing how the various circuits fit together.
FIG. 10 is a schematic flow chart of the logical operation by which the system is programmed to operate.
DETAILED DESCRIPTION OF THE INVENTION
The mine effects simulator system consists of a single type of simulated land mine, FIG. 1. The device is a combination tilt rod and pressure fuse type mine 1. The mine 1 is operative against any type of vehicle including an armor-class vehicle 2, such as the tank shown in FIG. 1.
Such vehicles 2 will include as part of the mine effects simulator system an electronic receiver box 3 located inside the vehicle. The purpose of the mine effects simulator system is to simulate the operation and the effects of the detonation of any of a plurality of land mines, such as that shown in FIG. 1, upon any of a plurality of vehicles, including the tank 2.
The vehicle 2, FIG. 1, with the receiver 3, is set up to receive low power radio frequency signals indicative of a certain type of detonation of a tilt rod/pressure fuse mine 1. It is imperative to note that the tilt rod/pressure fuse mine 1 does not carry an active explosive charge. What it does carry however, is activator circuitry for generating a low power radio frequency signal which indicates the activation of what would normally be a certain type of explosive reaction to the presence of the vehicle 2.
The receiver 3, FIG. 1, includes an antenna 4 for receiving a signal from the tilt rod/pressure fuse type mine 1. In a preferred embodiment this signal is a 49 MHz carrier with either a four or a five pulse code. These two codes distinguish the type of kill which will be further discussed below. The tilt rod/pressure fuse simulation mine 1, FIG. 2, includes a standard type tilt rod activation mechanism 5, a standard type pressure fuse activation mechanism 6 and electronic circuitry components 7. A long whip antenna 8 is connected to the electronic components and is of a sufficient length to be exposed above ground (to transmit a 49 MHz radio frequency signal) when the mine 1 is properly buried.
FIG. 2A shows an illustrative tilt/pressure type switching mechanism. Rod 5 would be rigidly connected to item 101. Tilting rod 5 caused actuator tilt item 104 to move which forces plunger 102 downward. That causes beveled ends of the plunger to force the top ends of sear 109 to move away from firing pin 110. Firing pin 110 was being held in place by those parts item 130 of sear 109. Spring 116 is under compression when pin 110 is in place as shown. Once items 130 are displaced pin 110 is forced downward by the spring. When pin 110 moves down it strikes the switch graphically illustrated by items 118, 119 and causes an electrical output from the switch. This produces a K-kill indication. Another switch within the body of the simulated mine responds to pressure and produces a M-kill indication. It should be recognized that the foregoing is merely an illustrative embodiment of a device which will respond to both a tilt and pressure. Others will be apparent to one of skill in the art.
It is to be understood that the simulation mine 1 does not contain any of the actual components of an operational, live tilt rod/pressure fuse type mine.
This simulation mine 1 of course, is absent the detonator and explosive charge of a normal mine. Where possible mine 1 to make its to add dead weight or ballast to the simulation mine 1 to make its physical characteristics as close as possible to the actual mine which it is intended to simulate.
The electronic circuitry 7 is comprised of logic circuitry and a 49 MHz radio transmitter. The electronic circuitry 7 is connected to a battery 9 and to a long whip antenna 8.
When the mine is activated the transmitter is activated and one of the pulse codes is placed on the 49 MHz frequency carrier depending on whether the tilt rod contact is made or the pressure fuse contact is made.
FIG. 3 is a block diagram of the system components for the mine effects simulator system of the present invention. This system has the ability to assess vehicle casualties. The simulation tilt rod/pressure fuse mine activated mechanically by the presence of the vehicle either by tilting the tilt rod or depressing the pressure fuse. The receiver 3 output is connected into a decoder circuit 10 which provides two principal functions. The first principal function is to decode the code on the radio frequency signal to determine whether it is a M-kill signal 11 or a K-kill signal 12. Once these signals 11, 12 are decoded they are sent on to processing circuitry 13 which determines and assesses the location of the simulated mine explosion with respect to the vehicle. The processing circuitry may be connected to a recorder/display unit 14 which records the operation of events with respect to movement of the vehicle and simulated mine detonations. This unit 14 may also provide a real-time visual display to the personnel within the vehicle to alert them as to a mine near miss, hit or kill.
In order to simulate the results of a mine detonation, the processing circuitry 13 is further connected to an audio/visual display device control circuitry 15. This audio/visual device control circuitry can be connected to smoke grenade devices 16, Hoffman type (audio/visual alarm devices) 17 and other type of devices 18 as may be selected for the particular type of vehicle. These other type of devices 18 can vary from simple lights to operating the vehicles horn.
The decoder 10 also includes circuitry for interfacing with a MILES system 19. This is a multiple integrated laser engagement system incorporated into many types of vehicles. The MILES itself is not a part of this invention.
When the mine circuitry, FIG. 4, is activated either by the tilt rod switch 20 or the pressure switch 21 power is supplied through one of the LM4148 diodes 22 to a 2N2222 NPN transistor 23 in an inverting configuration. The 2N2222 NPN transistor 23 causes the flip-flop formed by the two cross-connected NAND gates 24 to lock in at a "high" state. This disables the reset of the 555 timer 25 allowing it to oscillate and also turns on the 2N2222 NPN transistor 26 which supplies power to the transmitter/encoder chip LM1871 27 allowing it to transmit a 49 MHz carrier. The output (pin 3) of the 555 timer 25 is fed into the NAND gates 28 and 29. The other input of NAND gate 28 is tied to the tilt rod switch 20 and if this switch is closed a logical zero is sent to pin 5 of the transmitter/encoder chip LM1871 27 causing a four pulse code to be sent on the 49 MHz carrier. The other input of NAND gate 29 is tied to the pressure switch 21 and if this switch is closed a logical zero appears on pin 6 of transmitter 27 causing a five pulse code to be sent on the carrier.
The oscillation of the 555 timer 25 causes the codes being sent by the transmitter to be turned on and off. The circuitry of FIGS. 6A, 6B, 6C (hereinafter FIG. 6) counts the number of times the code is turned on and off and processes that information. The RC network 30 causes the 555 timer 25 to reset when the 15 k resistor discharges the 47 uF capacitor to the reset threshold level thus stopping the on/off switching of the codes.
The receiver, FIG. 5, is a superheterodyne receiver with digital outputs A and B. The four pulse code is output on channel A 31 and the five pulse code is output on channel B 32. These digital outputs toggle on and off corresponding to the on and off toggling of the transmitter.
The first part of FIG. 6 is the CD4518 Dual Synchronous Up Counter 33, this chip counts the incoming toggles of the A and B channels. If channel A toggles four times indicating a K-kill the RC Network 34 will delay it for approximately one second to see if there is an overriding M-kill on the B channel. If there is no M-kill the K-kill will cause output (pin 2) of the flip-flop 35 to go "low". If there is an M-kill the flip-flop 36 will go "high" on pin 13. When pin 13 goes "high" the counter 33 and the flip-flop 35 are both reset, this gives the M-kill priority. If neither channel A nor B toggles four times the RC networks of 37 and 38 will reset the counter 33 after approximately 2.2 seconds.
The flip-flops 35 and 36 are used to hold the data until the rest of the circuitry can process it. The processing consists of determining if there are breaching devices simulated on the vehicle and sending either an M-kill, a K-kill, or a near-miss code to the MILES equipment. If there are breaching devices a CD4518 Counter 44 and a CD4511 BCD-to-7 Segment Latch/Decoder/Driver 45 increment a 7-Segment display 46 to show the crew how many training mines they have encountered. The first two encounters will produce a near-miss code and the third will cause a K-kill or M-kill code to be sent to the MILES equipment.
The breaching device is simulated by putting power to 39 through the rotary switch 40. When the breaching device is portrayed the NOR gate 41 enables the counter 44 and allows it to increment on the falling edge of the pulse supplied by the one-shot formed by NOR gate 42, RC network 43, and NOR gate 41. If the count is less than three the four NAND gates 47 and the two NOR gates 48 load the near-miss code into the parallel-to-serial shift registers 49 and 50 of FIG. 6. If the count is three, the array of NOR gates 51 determine if the encounter was a K or M-kill and load the appropriate code into the shift registers 49 and 50 via the NOR gates 48.
The MILES signal conditioning portion of the signal processing circuit of FIG. 6 is made up of 49, 50, and 56 through 62. Here an oscillator circuit 56 supplies pulses to a type CD4060 frequency divider 57. The output pin 15 of the CD4060 frequency divider 57 is fed into the serial shift registers 49 and 50 and the jam circuitry 58. The jam circuitry 58 consists of a CD4040 counter and two, 4-input NAND gates. When the CD4040 counter reaches eleven the parallel data is jammed into 49 and 50 and the CD4040 counter of 58 is reset. The outputs 59 of the CD4060 frequency divider 57 are send into the 8-input NAND gate 60, this along with the serial output of shift register 50 creates the proper MILES pulse format. This pulse code is buffered by CD4011 2-input NAND gate 61 and a 2N2222 transistor 62 and is available for input into the MILES system.
The MILES code is sent when the output of NAND gate 51 goes "high" this is done by the same circuitry that loads the MILES codes. When NAND gate 51 goes "high" it also enables the counter 52, which is the other half of counter 44. This counter 52 receives input from the continuously running 555 timer 53 and when it counts four pulses it sends a "high" signal to reset the counter 33 and the flip-flops 35 and 36. It also resets itself after a short delay caused by the RC circuit 54.
The Hoffman/Smoke Grenade Relay, FIG. 7, is activated by the NAND gate 55, FIG. 6, only when a K or M-kill MILES code is being sent to the MILES computer.
FIG. 8 is a schematic of the two LM338K voltage regulators used to convert vehicle power, typically 24 volts, to 6 volts for the circuitry of FIGS. 5 and 6 and to 12 volts for the relay of FIG. 7.
FIG. 9 shows all of the previously discussed figures as they would fit together to form a complete system.
FIG. 10 shows a flow chart of the logical operation by which the system is programmed to operate. The first step 63 is to arm the mine after that it is determined whether a mine contact is made or not, step 64. If no mine contact is made then the system remains alert until it is retrieved or the battery goes dead.
However, if a mine contact is made then the system interrogates to determine if it is a tilt rod strike step 65. If there is not tilt rod strike determined in step 65 then interrogation is made to determine if the pressure plate has been hit step 66 and an M-kill signal has been sent step 67. If these steps 66 and 67 have been operated upon the mine then becomes inactive step 68.
If the tilt rod strike interrogation step 65 determines that there has been such a strike the next interrogation is determined whether the pressure plate has been hit step 69. If no pressure plate has been hit than a K-kill signal is sent 70 and the mine goes inactive step 68. If it has been determined in step 69 that the pressure plate has been hit then an M-kill signal is sent step 71 and the mine goes inactive step 68. The anti-tank training mines operate by transmitting a 49 MHz radio frequency (RF) signal when activated. The signal is of sufficiently low power to localize its effective radius to approximately 50 feet. This is sufficient to activate on-vehicle components of vehicles encountering mines, but not those of adjacent vehicles operating in a doctrinally correct formation.
When a mine is encountered, one of two RF codes will be generated: One code for catastrophic kill (K-kill) and another for mobility kill (M-kill). These signals are transmitted to on board vehicle receivers to be further processed.
Each mine is powered by a 9 volt battery, which will be connected when the mine(s) are issued to the receiving unit. Batteries are to be removed when the mines are returned to storage. The item referred to as a mine is actually a "mine core" component. The "mine core" can be used in a stand-alone configuration, and provide training realism (except for the physical characteristics of an actual mine).
To gain total realism, and additional protection for the "mine core", the mine core is meant to be emplaced in a prepared existing metal case mine, or in locally fabricated mines constructed of plastic, wood or concrete. The concrete mine is recommended, because of ease of construction, strength, and cost. When the "mine" is buried in soft ground its outer shell is not as important as when it is emplaced above ground. The strength of concrete provides additional stability and protection to the "mine core". The tilt rod/pressure fuse "mine core" has been designed for total battlefield realism to allow units to train as they will fight. The "mine core" is capable of providing the following training and realism:
a. Inserting the "mine core" into the mine simulates preparing existing mines for arming by inserting the firing chain boosters;
b. Screwing the tilt rod into the fuse, and the fuse assembly onto the "mine core" simulates attaching the fuse. Removing the safety pin and fuse stiffeners from the fuse simulates arming the mine;
c. The tilt rod is inserted into the fuse cap to arm the tilt rod function. The tilt rod/pressure fuse "mine core" can perform both type encounters, or can be configured to perform one or the other . . . allowing total realism in mine fuse selection;
d. A tilt switch in the "mine core" turns the firing circuit off if the mine is tipped over. If the mine is placed upright again it returns to "ready";
e. Training realism is provided by reversing the mine's arming sequence. This allows hand breaching, clearing the battlefield recovery of mines; and
f. The mines do not contain anti-handling devices, nor do they assess individual soldier casualties.
The vehicle receiver box assembly consists of a 49 MHz receiver; logic circuits and electronic components to activate a "Hoffman device", standard military smoke grenade or vehicle horn; logic circuits to differentiate between M and K-kill signals; and microprocessing to store, load and transmit appropriate binary codes to the hose vehicle's MILES system.
The vehicle receiver box assembly has built in capability to use all, or some of the functions listed above and may be used with MILES or future generation training system, or in a stand alone configuration. Additionally it can be used in conjunction with vehicles which have mechanical or electronic breaching systems employed. Vehicles with these devices will detonate, but ignore any mines they encounter.
Vehicles with blades, plows, rollers which activate placed (tilt rod/pressure fuse) mines will not be affected by the mine detonation, until the third encounter. At this time it is portrayed that the vehicle breaching device would be sufficiently damaged to allow the vehicle to encounter the mine. Mines encountered (number one through number two) would cause a "near miss/mine" encountered signal to be processed, but not acted on by the kill indicators in the vehicle receiver box, or MILES (if attached). This process does not effect FASCAM (a generic term representing all scatterable mine system) mine encounters unless the vehicle's electromagnetic breaching selection is operating.
Vehicles using the electromagnetic mine breaching selection will ignore FASCAM mine encounters. The near miss/mine encounter designator will function when the mine "detonates", but no damage to the vehicle occurs. This allows the vehicle crew to take action to notify other vehicles of the minefields existence. As long as the electromagnetic breaching selection is activated, the vehicle is protected from FASCAM mines.
Changes can be made in the above-described invention without departing from the intent and scope thereof. The above description is intended to be illustrative of the invention and not limiting.
|
A mine effects simulator system for simulating the operation and encounterf land mines and their potential effects on an armored vehicle. The system utilizes an authentic land mine activation mechanism, radio transmitter and logic circuitry and provides a radio frequency signal when activated by the proximity of an armored vehicle. The armored vehicle has a receiver device which receives the signal to determine a "hit" or "kill" based upon the time of the mine detonation with respect to mine to vehicle position.
| 5
|
The present invention refers to a measuring weft feeder which utilizes a yarn clamping device to prevent defects caused by yarn slippage and/or loose turns of yarn on the storage surface of the weft feeder.
BACKGROUND OF THE INVENTION
Measuring weft feeders are normally used for feeding jet looms with weft yarn, the stopping element being used for limiting the weft yarn length and being removed from the passage slot for such a period of time that the exact weft yarn length is drawn off, the yarn circulating around the storage body in the course of this process. In the stopping position, the stopping element defines the circumferential stop for the circulating yarn. The stopped yarn extends from the last turn on the storage surface at an oblique angle to the stopping element and then approximately axially to a yarn guide element or a yarn-insertion or auxiliary nozzle exerting a pulling force on the yarn. At the end of the yarn-insertion movement, a whipping effect will occur when the yarn has struck the stopping element, said whipping effect causing a noticeable increase in the yarn tension and, subsequently, a relief of yarn tension, and this will exert an influence on the turns of yarn up to the last turns on the storage surface. The tension of the last turns of the yarn will be relieved to such an extent that these turns will hang down freely. This may result in a displacement of the turns and it may interfere with the next insertion. It may also happen that a loose last turn falls off the storage surface without any external influence so that the next weft yarn will then be too long. A turn falling down may wind itself around the stopping device and cause yarn breakage. Several superimposed turns may be registered as one turn during the next insertion, and this will result in malfunction. When the yarn geometry is changed between the measuring weft feeder and the edge of the woven fabric during the working cycle of the loom, very lively and highly twisted yarn qualities tend to slip away below the stopping element due to the pulling force exerted by the yarn-insertion or auxiliary nozzle, even if said stopping element engages a recess provided in the storage surface. This will result in incorrect weft yarn lengths and in yarn defects which will be visible in the woven fabric later on. In order to eliminate this disadvantage, the stopping element must move deeply into the recess with a long operating stroke and this necessitates an expensive and strong operating magnet having a delayed response behaviour.
SUMMARY OF THE INVENTION
It is the object of the present invention to provide a measuring weft feeder of the type described at the beginning in the case of which yarn defects caused by loose turns on the storage surface or by a yarn slipping away below the stopping element are avoided.
In accordance with the present invention, this object is achieved by use of a measuring weft feeder that includes a storage body where yarn is stored by being wound thereon, a stopping device which defines a passage area where yarn passes through when being unwound off of said storage body, and a stopping element, which when placed in a stopping position, is moved transversely through the passage area so as to form a circumferential stop which prevents yarn from further unwinding off of said storage body by placing an oblique force upon the yarn. In addition, a yarn clamp, which is connected to and displaced by said stopping element, is used to prevent tension forces being created in and displaced throughout the yarn when it strikes the stopping element. When the stopping element is displaced through the passage area so as to function as a circumferential stop, the yarn clamp is placed in a passive clamping position. In this position, a direct clamping force is applied upon the yarn, thereby preventing tension from building up in the stored yarn when it strikes the stopping element.
In the case of this structural design, the yarn caught at the stopping element is stabilized by the yarn clamp to such an extent that the turns of the yarn on the storage surface will no longer loosen due to the increase in and relief of yarn tension downstream of the measuring weft feeder so that even lively, highly twisted yarns will no longer slip under the stopping element. The yarn clamp prevents the yarn from sliding back and it also prevents loosening of the yarn directly at the stopping element, since it fixes the yarn in a comparatively large area thereof. In view of the fact that the yarn clamp is adapted to be controlled, it will no longer exert any negative influence during the drawing-off movement of the yarn. The yarn clamp will be come effective precisely at the moment at which a critical condition of the stopped yarn occurs.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the subject matter of the invention are explained on the basis of the drawings, in which
FIG. 1 shows a schematic side view of a measuring weft feeder,
FIGS. 2A, 2B, and 2C show three associated views of a first embodiment, FIG. 2C being a view in the plane
I--I of FIG. 2B,
FIG. 3A, 3B, and 3C show associated views of two additional variants of embodiments,
FIGS. 4A, 4B, and 4C show three associated views of an additional embodiment,
FIGS. 5A, and 5B show an additional embodiment in two different positions, and
FIGS. 6A, and 6B show an additional embodiment in two different positions and in a drawing shown partly in section.
DETAILED DESCRIPTION
A measuring weft feeder M according to FIG. 1 serves to feed e.g. an air-jet loom (not shown) with weft yarn sections having an exactly measured length, said weft yarn sections being drawn off successively. The measuring weft feeder M comprises a housing G having arranged thereon a storage body F in the form of a drum which is provided with an external storage surface 1 for the yarn Y wound in turns W onto said storage surface 1 by a winding member 2. The yarn Y is drawn off a yarn supply coil, which is not shown, and is inserted into the measuring weft feeder M where it is wound in successive turns onto the storage surface 1 by the winding member 2, said winding member being adapted, to be driven such that it rotates. From said storage surface 1, the yarn Y is drawn off overhead (i.e. over one end of the drum) below a stopping device S, which is attached to the housing G, by means of a weft-insertion or auxiliary nozzle 3. The stopping device S includes a selectively extendable stopping element P and a controllable yarn clamp K.
According to FIGS. 2A, 2B and 2C, the storage surface 1 is provided with axial fingers 5 distributed in the circumferential direction. One finger 5 is in alignment with the stopping device S and it is provided with a recess 7 for a free end 8 of the stopping element P which is constructed as a pin. By means of an operating magnet 4, the stopping element P can be moved up to and into the recess 7 to the stopping position shown and retracted with the aid of a restoring spring, which is not shown. It is, however, also possible to push out the stopping element P by means of a pushing spring (not shown) and to retract it with the aid of the operating magnet 4 against the force of the pushing spring.
A passage slot A is defined between the stopping device S and the storage surface 1, the yarn Y passing through said passage slot A upon being drawn off in the circumferential direction. The yarn clamp K, which is arranged on the stopping device S, is provided with a clamping element C, in the present case a lamina or plate 6 with bent-up edges, which is positioned on the stopping element P and which is adapted to be moved together therewith from a position of rest indicated by the broken lines to the clamping position shown by the solid lines. The stopping element P forms a circumferential stop B for the yarn Y. The storage surfacer 1 forms a passive clamping surface 1' with which the clamping element C cooperates so as to clamp the yarn Y abutting on the stopping element P.
The stopping device S has provided therein an opening 9 for the clamping element C, said opening 9 being open at the bottom and being adapted to the shape of the clamping element C so that, when the stopping element P and the clamping element C are retracted, the yarn Y which may perhaps have been raised together therewith will be stripped off the free end 8. FIG. 2C shows clearly how the yarn comes into contact with the circumferential stop B after having been drawn off in the circumferential direction 10. The yarn has applied thereto a pulling force in the direction of an arrow 11 by means of the weft-insertion or auxiliary nozzle 3 and it is held in an approximately axially stretched condition. Upstream of the stopping element P, the yarn Y extends at an oblique angle to the next turn of the yarn on the storage surface 1. The clamping element C is large enough for extending beyond the edge of the engagement recess 7 and for fixing the yarn at least in two spaced-apart areas 12 and 13 so that the yarn Y cannot slip away below the free end 8 of the stopping element P.
In the embodiment according to FIG. 3A, the clamping element C is a leaf spring 16 which is bent into a U-shape or V-shape and which has its upper leg 17 secured in position on a shoulder 15 of the stopping element P. The lower leg 18 of said leaf spring 16 is movably guided on a lower part 14 of the stopping element P via a recess 19. It will be expedient to pretension the leaf spring 16 so that the leg 18 will be slightly raised when the yarn Y strikes the lower part 14 of the stopping element P and clamp the yarn Y in position. In the view from below of FIG. 3B, it can be seen that, if necessary, the lower leg 18 rests on the stopping element P so that it is guided thereon, said lower leg 18 being, however, still movable. In the embodiment according to FIG. 3C, which corresponds with the view of FIG. 3A, the clamping element C is a spring-wire bow 16' whose upper leg 17' is secured in position at the stopping element P and whose lower leg 18' is guided on said stopping element or extends round said stopping element with a certain amount of lateral play (recess 19'). Also the spring-wire bow 16' clamps the yarn Y, just as in FIG. 2C, at both sides outside of the engagement recess 7 on the passive clamping surface 1'.
The embodiments above are advantageous insofar as, due to the movement of the stopping element, the yarn clamp is displaced to a passive clamping position and is there ready to act on the yarn. When the yarn strikes the stopping element, the weft yarn will be an exactly measured length, and the yarn will fix itself automatically in the position so that there will be no inadmissable relief of the tension of the last turns of yarn on the storage surface, thereby preventing yarn from slipping away below the stopping element. The yarn is held comparatively stretched at the stopping element between at least two clamping points by means of the yarn clamp. It is thus possible to choose a small penetration depth of the stopping element as well as a short operating stroke for the stopping element, thus permitting the use of an inexpensive and rapidly responding operating magnet or pushing spring by means of which the stopping element is extended only a short stroke.
According to FIGS. 4A, 4B and 4C, the clamping element C is a leaf spring or a spring-steel component 20 which has been produced by punching or stamping and which has a fastening end 21 and a mouthlike cut-out portion 24 at the free end thereof. The leaf spring 20 is supported in the stopping device S via its fastening end 21. The mouthlike cut-out portion 24 extends round a transverse groove 22 of the stopping element P above the free end 8 of said stopping element P. The magnet 31 of the stopping element can be so strong that it will deflect the leaf spring 20 from the position of rest shown in FIG. 4A together with the stopping element P into the clamping position shown in FIG. 4B in which the yarn Y caught at the stopping element P is pressed against the passive clamping surface 1' on the storage surface 1. It is, however, just as well possible to pretension the leaf spring 20 in the direction of an arrow 23 and to fix it in the stopping device S in such a way that it will serve as a pushing spring for the stopping element P and push out said stopping element P as soon as the magnet 31, which is constructed as a restoring magnet, is de-excited. Furthermore, it would be possible to pretension the leaf spring 20 upwards as a restoring spring so that it will act against the magnet 31 serving as a pushing magnet. For the clamping element C, the opening 9 is provided in the stopping device S so as to keep the passage slot A free for the yarn Y in the position of rest. FIG. 4C shows a top view of a possible shape of the leaf spring 20.
In the embodiment according to FIG. 5A, the stopping element P serves as a driver for the clamping element C, which consists e.g. of a bent leaf spring 25, a lamina of plastic material, a wire bow or the like, and which is pivotably supported in the stopping device S in a pivot bearing 26. A driver connection 27 between the stopping element P and the clamping element C guarantees that, in the stopping position of the stopping element P (FIG. 5B), the clamping element will move at least partially from the stopping device S into the passage slot A and clamp the yarn Y as soon as said yarn Y has come into contact with the stopping element P. In the clamping position, the clamping element defines together with the storage surface 1 a clamping nip 28 which narrows in the direction of the stopping element P and in which the yarn Y is decelerated in the course of its movement towards the stopping element P. The clamping element C can be constructed such that it has little mass so that the actuating force applied by the stopping element P will remain small.
FIG. 6A shows an additional embodiment in the position of rest, whereas FIG. 6B shows said embodiment in the stopping or clamping position. The clamping element C is a leaf spring 30 pretensioned in the direction of an arrow 23, said leaf spring 30 having its ends supported in the stopping device S at 31' and resting on a shoulder 29 of the stopping element P in the central area thereof. The magnet 31 is constructed as a traction magnet which, when excited, generates a tractive force in the direction of the arrow 32. For moving the stopping element P to the stopping position according to FIG. 6B, the magnet 31 is de-excited so that the leaf spring 30 will urge the stopping element P into the engagement recess 7 provided in the storage surface 1. At the same time, the leaf spring 30 partly enters the passage slot A for clamping the yarn Y which has arrived at the stopping element 8 and for defining a clamping nip which narrows in the direction of the stopping element P. The opening 9 in the stopping device S is adapted to the shape of the leaf spring 30 at least in the outlet area thereof so that the abutting yarn Y will be stripped off when the stopping element P is being raised.
It would just as well be, possible to support the leaf spring 30 according to FIG. 6A and 6B such that it is pretensioned in the opposite direction and to use it as a restoring spring for the stopping element P. In this case, it would be necessary that the magnet 31, when excited, generates a magnetic force acting in the direction of the arrow 23.
The yarn clamp K arranged in the stopping device S could just as well be provided with a structural design deviating from the embodiments shown. The important point is that the yarn clamp is moved and advanced to its clamping position and displaced to its position of rest in synchronism with the stopping element so that it will only become effective if also the stopping element fulfills its stopping function. Due to the arragnement of the yarn clamp in the stopping device, a separate holding means for said yarn clamp can be dispensed with. Furthermore, it is not necessary to provide an independent control for the yarn clamp, since said yarn clamp makes use of the stopping device or rather of the stopping element.
An advantageous expedient of the present invention is that the yarn clamp is actuated in synchronism with the stopping element when said stopping element has to catch the yarn, whereas the yarn clamp will remain inactive when also the stopping element is passive.
Also, a structurally simple arrangement is provided in the embodiment in which the storage surface defines the passive clamping surface so that a simple clamping element will suffice for fixing the yarn. In view of the fact that the clamping element is supported in an opening of the stopping device in its position of rest, the yarn, which may perhaps be entrained when the stopping element is being retracted, can be stripped off.
An alternative and reliable embodiment is disclosed due to the fact that the clamping element is supported in the stopping device such that it is adapted to be deflected and need not be moved by any component other than the stopping element, so that the actuating force which the stopping element has to apply to the yarn clamp is very small. The response behavior of the stopping device will not noticeably be impaired.
Further, in the case in which the clamping element fixes the yarn outside of the edge of the engagement recess at several points, even if a small penetration depth has been chosen for the stopping element, the yarn will not slip away below the stopping element.
Also, a structurally simple, functionally reliable and space-saving embodiment is disclosed since, by means of a leaf spring, it will additionally be possible to achieve a desirable elasticity and, consequently, a deceleration of the unwinding operation which becomes effective gradually when the yarn is being clamped.
A particularly advantageous embodiment is also disclosed wherein the leg of the leaf spring which faces the passage slot and which is movably guided on the stopping element clamps the yarn gently but reliably. Moreover, the movable lower leg of the leaf spring will strip off the yarn when the stopping element is being retracted. The retracting movement of the stopping element may be supported by the leaf spring the tension of which is relieved.
In the case of the embodiments wherein the clamping element has an additional function causing the stopping element to move in the pushing direction or in the restoring direction, components in the stopping device which have hitherto been necessary for this purpose, e.g. a pushing spring or a restoring spring, are either no longer necessary or they can be constructed as weak components which will, consequently, have small dimension.
Although a particular preferred embodiment of the invention has been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention.
|
A measuring melt felder (M) has a storage body (F) for the thread (Y) wound in turns (W) and at least one stopping device (S) outwardly associated to the storage body (F) that delimits a thread (Y) passage slot (A). A stopping element (P) capable of moving transversely through the passage slot (A) to a stopping position acts as a circumferential stop (B) for the thread (Y). The stopping device (S) has, associated with the stopping element (P), an adjustable thread clamp (K) for the thread (Y) held at the stopping element (P).
| 3
|
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application claims benefit to provisional patent application No. 60/629,006 (WFVA/CyVERA nos. 714-1.18/CV 75PR), filed Nov. 17, 2004, which is hereby incorporated by reference in their entirety.
[0002] The following cases contain subject matter related to that disclosed herein and are incorporated herein by reference in their entirety: U.S. patent application Ser. No. 10/661,116 (CyVera Docket No. CV-0044), filed Sep. 12, 2003, entitled “Method of Manufacturing of a Diffraction grating-based identification Element”.
BACKGROUND OF INVENTION
[0003] 1. Technical Field
[0004] The present invention relates to a method and apparatus for manufacturing a filament having an easily removed protective coating, as well as a method and apparatus for easily removing the protective coating from the filament.
[0005] 2. Description of Related Art
[0006] Optical filament is typically manufacturer with a protective coating that protects the filament during its handling from the time it is manufactured to the time its is used in any particular application.
[0007] When such filament is used to make microbeads, the fabrication of micro beads requires as a starting material a very small glass filament, approximately 28 microns in diameter. Before codes can be written into the filament the protective coating must be removed. For this, there are different known techniques, including thermal-mechanical, thermal, chemical-mechanical and chemical (e.g. sulphuric acid), for removing the protective coating from the filament.
[0008] In particular, the thermal-mechanical process involved heating the coating to about 500 degrees C. while pulling it through a mechanical die, which physically strips the coating off the filament. The approach works on conventional filament sizes (125 um-65 um) with conventional coatings, such as a UV cured acrylate. However, due to the mechanical nature of the process, the filament was inevitably weakened. Moreover, this approach breaks down with filament smaller than 65 um. Since the target filament size for micro beads is 28 microns (um), this approach is not effective.
[0009] The thermal ablation method may be used to remove the protective coating from the filament that is used to make microbeads. This method involves using superheated nitrogen (˜1000 degrees C.) to essentially evaporate the coating off the filament without ever needing to touch it with a die. Although this method essentially works in that it removed the coating, it has the disadvantage of having a slow speed combined with questions surrounding the effectiveness of the strip at the molecular level.
[0010] In view of this, there is a need in the industry to remove the protective coating from the filament that overcomes the aforementioned disadvantages of the methods known in the art.
SUMMARY OF INVENTION
[0011] The present invention provides a new and method and apparatus for applying a removable protective coating to the filament during a draw process that can be easily removed with a reasonably benign, and environmentally-friendly, solvent such as water, or if necessary, acetone or ethanol. The protective coating can be easily dissolved in-line with the spooling process.
[0012] The material may include a water-soluble “wax-like” material called Aquabond 65, distributed by Aquabond Technologies, as well as other grades of Aquabond such Aquabond 55 and Aquabond 85, which behave essentially the same but are dissolved at different temperatures.
[0013] Another material, which may be used for this application is called Crystalbond. However, this is soluble in acetone, which is more hazardous and therefore more expensive to work with.
[0014] The present invention also relates to the method and Illumina, Inc. Proprietary apparatus for easily removing the protective coating with the reasonably benign, and environmentally-friendly, solvent, as well as the microbeads resulting from using all of these new techniques.
[0015] The present invention also has the following advantages, including minimizing the volume of reagent needed, providing easy to set up devices, and providing easy to scale up and down depending on the requirements of the application.
BRIEF DESCRIPTION OF THE DRAWING
[0016] The drawing, which are not drawn to scale, include the following:
[0017] FIG. 1 shows apparatus for applying a protective coating to a filament being drawn in a draw tower that is easily removable according to the present invention.
[0018] FIG. 2 , including FIGS. 2 ( a ) and ( b ), show two graphs, one having break strain (% dl/length) plotted versus cumulative failure probability, the other having mean distance between failure (meters) plotted versus mean load (grams).
[0019] FIG. 3 shows a method for removing or stripping the protective coating from a filament according to the present invention.
[0020] FIG. 3 a shows one or more alternative methods for removing or stripping the protective coating from a filament according to the present invention.
[0021] FIG. 4 shows another method for removing or stripping the protective coating from a filament according to the present invention.
[0022] FIG. 5 shows four photographs of the filament based on these new techniques, including FIG. 5 ( a ) showing a filament having full coat; FIGS. 5 ( b ) and ( c ) showing a filament after stripping using the method in FIG. 4 , and FIG. 5 ( d ) showing a filament after stripping using the method in FIG. 3 .
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 : Applying the Coating
[0023] FIG. 1 shows a drawing tower generally indicated as 10 having a preform 12 arranged in a furnace 14 , in which a filament 16 of bare glass is drawn. In operation, the bare filament 16 is coated by passing it through a cup 18 that has a hole in the bottom and is filled with an Aquabond coating 20 . A heater 22 arranged in relation to the cup 18 provides heat to the cup 18 for maintaining it at a predetermined temperature. After the filament is coated with Aquabond 20 , the filament 16 with the Aquabond coating 20 thereon is taken-up on a wheel or spool 24 , as shown.
[0024] FIG. 5 ( a ) shows a filament 16 having a full coating of Aquabond according to the present invention.
[0025] In effect, the method involves applying the Aquabond coating 20 directly to the filament 16 during the draw process. Like other thermoplastic coatings the material transitions from a solid to a liquid at an elevated temperature. Aquabond 65 begins to soften at about 60 degrees C. and becomes watery at about 80 degrees C. To apply the Aquabond coating 20 to the filament 16 , the heated cup 18 with the small hole or die is used to establish the diameter of the coating material (<about 100 microns works best). The optimal viscosity was achieved when the cup 18 was heated to about 70 degrees C. It was determined that once the filament 16 is drawn and spooled on a mandrel, it can be handled normally without risk of degrading its pristine strength.
[0026] FIG. 2 ( a ) shows a graph of the failure statistics. Bare filament tends to be extremely fragile, to the extent that it will not stay intact while it is still on the spool. Handling such filament in long contiguous lengths is virtually impossible. A characteristic Weible plot will exhibit a long slow decay rolling off less than 1% strain. Conversely, high strength telecom style filament with an optimized robust coating will exhibit a very sharp roll off starting near 7%. Such a curve indicates that the probability of failure even at high tensile strains (greater than about 6%) is very low. The failure statistics for the Aquabond coated filament, not surprisingly, indicate that the coating is not as good at maintaining strength as filament with those coatings which are designed to not be easily removed. However, the relatively steep curve indicates that the coating is providing a significant level of protection against failure use to mechanical abrasion and attack from humidity.
[0027] FIG. 1 a shows, by way of example, a die/cup arrangement generally indicated as 30 having a die 32 arranged in a cup 34 for use according to the present invention. The cup 34 holds the coating material which is applied to the filament F as it passes through the arrangement. It has been determined by experimentation that the die size (D die ) to filament (D filament ) size is about 2:1 for the optimal application of the coating. This unique ratio results in self-centering forces causing the filament to pass through the center of the die 32 to increase the uniformity of the coating being applied to the filament F. In one embodiment, the die 32 is made from a silicon mold with a diameter (D die ) in a range of about 60-80 microns, and preferably about 75 microns, depending on the diameter (D filament ) of the filament.
[0028] FIG. 1 b shows an alternative embodiment to that shown in FIG. 1 . Similar elements are shown and described with similar reference numerals. The overall objective is to cool the coated filament in a reasonably short distance possible to keep the height/length of the overall draw tower to a minimum. In FIG. 1 b , a variable speed capstan 26 is preferably arranged at a minimum distance D minimum from the preform 12 so as to provide cooling and curing of the coating on the filament. The cooling time depends on the coating thickness and the temperature difference between the surrounding environment and the filament, and the cooling distance depends on the draw velocity of the filament and the cooling time. Alternatively, a cooling tube may be added to accelerate the cooling of the coating material on the filament. The capstan 26 may be independently controlled by a capstan controller (not shown).
[0029] Embodiments are also envisioned in which multiple die/cup arrangements like element 30 used in an in-line technique for applying the protective coating to the filament 16 . This embodiment may include a series of arrangements 30 such as that shown in FIG. 1 a . This approach randomizes the coating centering for a more even application of the coating.
[0030] FIG. 1 c shows a fiber F having the removable coating 20 and a substrate 21 in the form of a device.
Removal of the Coating
[0031] FIG. 3 shows a method and apparatus generally indicated as 52 according to the present invention for easy removal of a protective coating 20 from a filament 16 , which is achieved by drawing the filament 16 off a spool 54 and through a 24 inch long Teflon tube 56 with hot water flowing through it, which is known herein as the hot aqueous stripping method. Although the present invention is described using a 24 inch long Teflon tube 56 , the scope of the invention is intended to include using other length tubes and tubes made from other materials. As shown, at either end of the tube 56 there are small diameter orifices 58 , 60 (e.g. about 0.020″). Although the scope of the invention is not intended to be limited to any particular orifice diameter, it has been found through experimentation that the tighter the overall fit is between the small diameter orifices 58 , 60 and the filament 16 , the better the overall method operates. A short distance from each end, two respective end ports 62 , 64 are tied into the tube 56 to allow the flow of respective liquids into the tube 56 , and a center port 66 located in the middle of the tube 56 is arranged so that liquid can be removed from the tube 56 . Liquid is drawn in through the two end ports 58 , 60 by applying a vacuum to the center port 66 using a vacuum pump 68 and collected in a tank 69 . This prevents liquid from flowing out the small orifices 58 , 60 at the ends. This three-port configuration also enables the flow of two different liquids at the same time, but separated by a virtual boundary in the middle of the tube 56 .
[0032] The process uses a hot aqueous solution of detergent 70 in a temperature range of about 65-100 degrees Celsius (preferably about 90 degrees C.) in one section generally indicated as 71 provided from a container 72 and pure hot water 74 also in a temperature range of about 65-100 degrees Celsius (preferably about 90 degrees C.) in another second section 75 provided from a container 76 . The aqueous solution detergent 70 is designed to dissolve the water-soluble coating, while the pure water is used to rinse or flush any residue in or from the detergent 70 and to remove undesirable entrained air. It has been found that linear draw rates exceeding 20 meters/minute have been achieved with the 24″ long tube 56 and modest water usage (less than 2 gallons/hour), although the scope of the invention is not intended to be limited to any particular draw rate. In principle, the system is scalable to nearly any linear feed rate, providing the length of the tube 56 is design to provide adequate dwell time in the hot aqueous solution 70 . In addition to being highly effective at cleaning the filament 16 , easy to use, environmentally friendly, and providing high throughput, this method produces very low residual tension on the filament 16 , which is particularly important when ultra fine diameter filament is used (less than 40 microns). As shown, after exiting the tube 56 , the stripped or bare filament 76 is wound on a take-up spool 80 .
[0033] FIG. 5 ( d ) shows the bare or stripped filament using Aquaclean according to the method shown in FIG. 3 .
[0034] In alternative embodiments, water may also be drawn from a tap or line having an in-line heater with the Aquabond metered into one line and provided to port 62 and the hot water alone provided to tap 64 . Moreover, instead of using the tank 69 , the liquid may be drawn from port 66 into a line and drawn from the tube 56 .
[0035] Embodiments are also envisioned in which the tube 56 is heated to keep the liquid at a desired temperature consistent with that described herein.
[0036] Embodiments are also envisioned in which multiple tubes like element 56 are used in an in-line technique for removing the protective coating from the filament. This embodiment may include a series of arrangements such as that shown in FIGS. 3 and/or 3 a , or a series of arrangement that may include a tube such as 56 having Aquabond cleaning, followed by a tube such as 56 having a hot water cleaning, etc. The scope of the invention is not intended to be limited to any particular type or kind of in-line arrangement that may be configured consistent with that shown and described herein.
[0037] Embodiments are envisioned using a camera suitably arranged for inspecting the bare filament 76 . Such a camera may be viewed by an operator or inspector for evaluating quality control, or a camera signal from the camera may be fed to a suitable processing device for analyzing the image in the camera signal and adjusting the operation of the overall device based on the same, including but not limited to adjusting the draw rate of the filament being fed through the tube 56 , as well as the flow of the liquid to/from the tank 56 .
[0038] Embodiments are also envisioned in which the protective of the filament is removed by steam cleaning, as well as other suitable techniques like chemical cleaning or gas cleaning, consistent with that described herein.
[0039] Moreover, the scope of the invention is not intended to be limited to using a vacuum pump for drawing the liquid out of the tube 56 . For example, embodiments are envisioned using other type or kind of pumps for drawing the liquid out of the tube 56 either now known or later developed in the future, including but not limited to a diaphragm pump.
[0040] FIG. 3 a shows an alternative embodiment of the present invention in which the tube 56 also has a rumble strip 57 arranged in, or forming part of the interior surface of the tube 56 . By way of example, the rumble strip 57 may consist of a corrugated surface that helps to break up the laminar flow of the liquid in the tube 56 . As shown, the rumble strip 57 is arranged or forms part of the upper and lower interior surface; however, embodiments are envisioned in which the rumble strip 57 is circumferentially arranged about the interior surface as well. FIG. 3 a also shows an ultrasonic device 59 arranged in relation to the tube 56 which may be used to improve stripping efficiency and to keep the length of the tube 56 to a minimum.
[0041] An embodiment of the present invention is also envisioned in which the tube 56 has a transparent top surface in order for an operator to look inside for contaminants.
The Graphs in FIGS. 2 ( a ) and ( b )
[0042] FIG. 2 ( b ) illustrates the significance of maintaining a low working load. For the filament characterized by the failure statistics in FIG. 2 ( a ), a predictive model was made to estimate the mean distance between failure for a range of working tensile loads. The graph in FIG. 2 ( b ) shows that as the load (y-axis) decreases, the mean distance between failures increases. For example, the maximum usable operating load must be maintained less than 100 grams to achieve a mean distance of failure of greater than 600 meters.
FIG. 4 : Alternative Method—the Bath Method
[0043] FIG. 4 shows a bath method generally indicated as 102 that was also developed as an alternative to the method shown in FIG. 3 . The bath method involves drawing a filament such as 16 coated with Aquabond 20 from a supply spool 104 through a bath 106 having a hot aqueous detergent 108 . The hot aqueous detergent 108 strips the Aquabond 20 off the filament, resulting in a stripped filament 110 that is wound on a takeup spool 112 . As shown, the coated filament 16 is first drawn over a spool/wheel 114 before entering the bath 108 , drawn around a spool/wheel 116 in the bath 118 and over a spool/wheel 118 , then onto the takeup spool 112 .
[0044] FIGS. 5 ( b ) and 5 ( c ) show a typical photograph of the filament 110 stripped with Aquaclean using this method. The visible residue 111 on the surface of the filament 102 was characteristic of this approach and led the inventors to develop the aforementioned improved method shown and described in relation to FIG. 2 .
FIG. 6 : Trough Stripper
[0045] FIG. 6 shows another embodiment generally indicated as 200 according to the present invention, wherein the filament 201 goes through 1, 2, 3 or more small tanks 202 , 204 through a groove 206 a , 206 b , 208 a , 208 b on both end. A liquid in the form of a cleaning solution is pumped via tubes 209 inside the tanks 202 , 204 and overflows into a secondary container 210 below. The overflow can be either on both end where the grooves 206 a , 206 b , 208 a , 208 b are, or all around as shown. In the secondary container 210 the liquid is drained by tubes 211 to a pump 212 where it is warmed/filtered and recirculated back to the upper container 202 , 204 .
[0046] Alternatively, the scope of the invention is intended to include a system having one of each arrangement to accommodate various properties of liquid, for instance if the liquid cannot bead up then the groove become necessary.
[0047] This concept is designed to limit the amount of liquid used, and maximized the usage of liquid by using a re-circulation system. It minimizes the chemical waste and loss of heat.
[0048] The quality of liquid can be monitored in the recirculation loop and a supply of fresh cleaning solution could be added replacing and pushing to waste partially “dirty” cleaning solution.
FIGS. 7 a , 7 b , 7 c : The Overflow Stripper
[0049] FIGS. 7 a , 7 b , 7 c show an embodiment of the invention generally indicated as 300 , wherein the cleaning solution is prepared in a tank 302 , then by a gravity feed, or with a pump (not shown), the liquid is pushed (see arrows 303 ) into the cleaning container 304 for cleaning the filament 301 . The level of liquid increase until it fills completely the small tank and starts to overflow (see arrows 305 ). Below the small tank is a secondary container 306 collecting the overflowed liquid. At one end a tube connected to a pump 308 brings the liquids back to the container 302 (or the pump).
[0050] FIG. 7 c shows an embodiment generally indicated as 400 in which one container 402 has Aquaclean for cleaning the filament 301 and the other container 404 has water, consistent with that described herein.
FIG. 8 : Surface Tension Stripper
[0051] FIGS. 8 a , 8 b show an embodiment of the present invention generally indicated as 500 , using the concept of a meniscus stripper. Similar elements in FIGS. 6 and 8 a have similar reference numerals with the additional of 300 to the reference numerals in FIG. 8 a . In FIG. 8 a , the filament 501 goes through 1, 2, 3 or more small tanks 502 , 504 . The cleaning solution is pumped via tubes 509 inside the tanks 502 , 504 and overflows into a secondary container 510 below. However, in this embodiment, the filament 201 does not go through grooves as described in relation to FIG. 6 , but instead surface tension of the liquid and the resulting beading up is conveniently use to allow the liquid to rise above the edge of the upper channel, and create a volume of liquid where the filament 201 can get cleaned. In the secondary container 510 the liquid is drained by tubes 211 to a pump 512 where it is warmed/filtered and recirculated back to the upper container 502 , 504 .
[0052] FIG. 8 b shows an alternative embodiment generally indicated as 600 , where there is having an inlet 602 of liquid and an overflow on the other side. At the outlet, after the overflow the liquid is monitored for change of turbidity, or any optical change of the liquid. If the liquid properties change due to contamination or increase concentration by the material it is suppose to clean, then a system controlling the flow rate of liquid in the inlet, increase the flow rate to bring the cleaning liquid to what it should be. The filament 601 to be cleaned move from the left to the right and the liquid in the opposite direction, so the dirtiest liquid face the incoming filament 601 and the clean filament has the cleanest solution. The system can have sonic device 625 to help the cleaning, an infrared lamp 630 prior to it to fragilised/liquefied the coating of the filament, and a heater 635 to maintain the overall apparatus at a desired temperature. The edge of the liquid channel may be coated with Teflon 640 to allow the liquid to bead up and increase the usable volume of liquid. The apparatus can be closed by a lid (not shown) to minimize evaporation and change of concentration, dirt and dust contamination, potential exposure to the hot liquid by an operator, and to minimize overall heat loss.
[0053] An Infrared devise 650 can be added if it is required to increase the speed of the cleaning and if the overflow system cannot keep up in removing the filament coating. It is also possible to use much higher temperature acceptable by the cleaning solution.
[0054] The sonic device 625 can be added to maximize the cleaning efficiency
Applications
[0055] Microbeads made using the aforementioned techniques may be used in many different applications, including those set forth in the following cases, which are incorporated herein by reference in their entirety: U.S. patent application Ser. No. 10/661,234 (CyVera Docket No. CV-0038A), filed Sep. 12, 2003, entitled “Diffraction Grating-Based Optical Identification Element”; U.S. patent application Ser. No. 10/661,031 (CyVera Docket No. CV-0039A) filed Sep. 12, 2003, entitled “Diffraction Grating-Based Encoded Micro-particles for Multiplexed Experiments”; U.S. patent application Ser. No. 10/661,082 (CyVera Docket No. CV-0040), filed Sep. 12, 2003, entitled “Method and Apparatus for Labeling Using Diffraction Grating-Based Encoded Optical Identification Elements”; U.S. patent application Ser. No. 10/661,115 (CyVera Docket No. CV-0041), filed Sep. 12, 2003, entitled “Assay Stick”; U.S. patent application Ser. No. 10/661,836 (CyVera Docket No. CV-0042), filed Sep. 12, 2003, entitled “Method and Apparatus for Aligning Microbeads in order to Interrogate the Same”; U.S. patent application Ser. No. 10/661,254 (CyVera Docket No. CV-0043), filed Sep. 12, 2003, entitled “Chemical Synthesis Using Diffraction Grating-based Encoded Optical Elements”; U.S. patent application Ser. No. 10/661,116 (CyVera Docket No. CV-0044), filed Sep. 12, 2003, entitled “Method of Manufacturing of a Diffraction grating-based identification Element”; and U.S. patent application Ser. No. 10/763,995 (CyVera Docket No. CV-0054), filed Jan. 22, 2004, entitled, “Hybrid Random Bead/Chip Based Microarray”, US Provisional Patent Applications, Ser. Nos. 60/609,583, 60/610,059 and 60/609,712, all filed Sep. 13, 2004 (CV-0082PR, 83PR and 84PR); U.S. Provisional Patent Application Ser. Nos. 60/611,205, 60/610,910, 60/610,833, 60/610,829, 60/610,928, all filed Sep. 17, 2004 (CV-0085PR, 86PR, 87PR, 88PR and 89PR); U.S. Provisional Patent Application Ser. No. 60/611,676, filed Sep. 20, 2004 (CV-0091PR); and U.S. patent application Ser. No. 10/956,791, filed Oct. 1, 2004 (CV-0092 US).
SCOPE OF THE INVENTION
[0056] The dimensions and/or geometries for any of the embodiments described herein are merely for illustrative purposes and, as such, any other dimensions and/or geometries may be used if desired, depending on the application, size, performance, manufacturing requirements, or other factors, in view of the teachings herein.
[0057] It should be understood that, unless stated otherwise herein, any of the features, characteristics, alternatives or modifications described regarding a particular embodiment herein may also be applied, used, or incorporated with any other embodiment described herein. Also, the drawings herein are not drawn to scale.
[0058] Although the invention has been described and illustrated with respect to exemplary embodiments thereof, the foregoing and various other additions and omissions may be made therein and thereto without departing from the spirit and scope of the present invention.
[0059] Moreover, the invention comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth.
[0060] It will thus be seen that the objects set forth above, and those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.
|
The present invention provides a filament with an easily removable protective coating as well as a method and apparatus for applying the protective coating to the filament during a draw process that can be easily removed with a reasonably benign solvent such as water, or if necessary, acetone or ethanol. The protective coating is water-soluble and can be easily dissolved in-line with a spooling process. The coating material may include a water-soluble “wax-like” material called Aquabond 65, distributed by Aquabond Technologies, as well as other grades of Aquabond such Aquabond 55 and Aquabond 85, which behave essentially the same but are dissolved at different temperatures.
| 3
|
FIELD OF INVENTION
[0001] The present invention relates to a field control method and system. More particularly, but not exclusively, the present invention relates to a method and user interface system for changing the values of a field by use of a virtual slider.
BACKGROUND TO THE INVENTION
[0002] Software programs exist which have user interface elements that enable the user to change the values of a field.
[0003] Present solutions to change the values of a field include the user entering in the new value manually by typing a string of characters from a keyboard or using a software mechanism called a slider.
[0004] There are visual sliders which can be represented on a display by a bar, optionally with buttons at each end marked with arrows and a smaller bar visible between the ends of the first bar whose position relative to the first bar gives an approximate indication of the value of the field.
[0005] There are also virtual sliders. A simple virtual slider works by a user moving a pointer by the use of a mouse or other device over the field to be adjusted and clicking a button, such as a mouse button, and moving the pointer to the left while the button is depressed (dragging the pointer) to decrement the value of the field or the right to increment the value. One known implementation of a virtual slider enables a user to define the magnitude of change by pressing specific keys on a keyboard. Another known implementation utilizes variation in the Y axis of mouse movement (or Y axis positions relative to the field) to change magnitude and decrement or increment the value of the field relative to mouse motion in the X axis according to the magnitude.
[0006] These approaches have the following difficulties:
[0007] The keyboard modified virtual slider method introduces another input device, thereby complicating the process and requiring the use of two hands to operate.
[0008] The Y axis virtual slider method requires precise movement of the mouse as small Y axis movements and small X axis movements can result in large value changes.
[0009] The Y axis virtual slider requires motion in 2 axes to affect a single value.
[0010] The Y axis virtual slider has fixed ranges of magnitude which, depending on the implementation, may not correspond to the magnitude of the value to be edited.
[0011] The magnitude defined by both methods is either unknown by the user or requires an additional interface element to display.
[0012] It is an object of the present invention to provide a field control method and system which enables a user to change values within a field by use of a virtual slider and overcomes the above difficulties.
PREFERRED EMBODIMENTS OF THE INVENTION
[0013] According to a first aspect of the invention there is provided a method of controlling a field, the method including the steps of:
[0014] i. displaying a value from the field on a display device;
[0015] ii. selecting a digit of the value displayed in response to user input from a pointer device; and
[0016] iii. changing the value by the magnitude of the selected digit in response to user input from a pointer device.
[0017] The pointer device is a user input device for controlling the pointer within a graphical user interface. The pointer device may be a mouse, a scroll wheel mouse, a trackball, a joystick or stylus and graphics tablet.
[0018] The digit may be selected by using the pointer device to position a pointer over the digit and pressing and holding down a button, such as a mouse button, or by pressing and releasing a button. The digit may be selected by using the pointer device to press and hold down a button and dragging the pointer over the digit.
[0019] The magnitude of the selected digit is the position of the digit within the value. If the digit is the third digit to the left of the decimal point within a base-10 value then the digit has the magnitude of 100 (10 2 ). If the digit is the third digit to the left of the decimal point within a base-16 value represented using the following digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F; then the selected digit has a magnitude of 256 (16 2 ).
[0020] If the value within a field is changed by the magnitude of the selected digit then the value is increased or decreased by the amount of the magnitude. Therefore if the magnitude of the selected digit is 100, the value will be increased by the amount 100 or decreased by the amount 100 for each increment or decrement of the pointer position along an axis.
[0021] Movement of the pointer device by the user may change the value by the magnitude of the selected digit.
[0022] Movement of the pointer device to the left may decrease the value by the magnitude of the selected digit.
[0023] Movement of the pointer device to the right may increase the value by the magnitude of the selected digit.
[0024] The value may be changed in multiples of the magnitude in proportion to the displacement of the pointer device.
[0025] The selected digit may be signified on the display device by highlighting the digit.
[0026] According to a further aspect of the invention there is provided a method of controlling a first field and any number of associated fields, the method including the steps of:
[0027] i. displaying the value of the first field and values of the associated fields;
[0028] ii. selecting a digit of the value of the first field in response to user input from a pointer device; and
[0029] iii. changing the value of the first field and values of the associated fields by the magnitude of the digit selected in response to user input from a pointer device.
[0030] Fields may be defined as associated with each other by the software application using the method.
[0031] The value of first field may be changed by movement of the pointer device along one axis and the value of an associated field may be changed by movement of the pointer device along a different axis.
[0032] Further associated fields may be changed by movement of the pointer device along different axes. For example, the pointer device may be a mouse with a scroll wheel, in which case the scroll wheel adds a third axis of movement.
[0033] According to a further aspect of the invention there is provided a user interface system for controlling a field, the system comprising:
[0034] i. a processor for changing a value in response to movement of a user input device;
[0035] ii. memory for storing the value;
[0036] iii. a user input device to select a digit of the value and to provide feedback to the processor to change to value; and
[0037] iv. an output device for displaying the value.
[0038] The user input device may be a mouse or a similar device which can control a pointer within a graphical user interface such as a scroll wheel mouse, a joystick or a track-ball or a stylus and graphics tablet.
[0039] According to a further aspect of the invention there is provided a user interface system for controlling a first field and any number of associated fields, the system comprising:
[0040] i. a processor for changing the value of the first field and values of the associated fields in response to movement of a user input device;
[0041] ii. memory for storing the values of the first and associated fields;
[0042] iii. a user input device to select a digit of the value of the first field and to provide feedback to the processor to change the values of the first and associated fields; and
[0043] iv. an output device for displaying values of the first and associated fields.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] The invention will now be described by way of example with reference to the accompanying drawings in which:
[0045] [0045]FIG. 1: shows a state transition diagram illustrating the method.
[0046] [0046]FIG. 2: shows a visual representation of an example of one implementation of the method for controlling a field.
[0047] [0047]FIG. 3: shows a visual representation of an example of one implementation of the method for controlling a first field and an associated second field.
[0048] [0048]FIG. 4: shows a visual representation of an example of one implementation of the method for controlling a first field and two associated fields.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0049] The present invention relates to a method and a system for providing a user interface to enable the changing of a value within a field. The method involves the selection of a digit of the value and changing the value by integer steps of the magnitude of the digit.
[0050] Referring to FIG. 1, the method may be implemented as a widget. A widget is a software module within an application that provides an element for the graphical user interface such as displaying information or providing a specific way for a user to interact with the application.
[0051] The application which is using the widget will open the widget in step 1 in relation to a specific field. The widget will wait in step 2 until a user presses a mouse button when the pointer is over the field in step 3 . The user may be using another device such as a trackball or a joystick.
[0052] The widget will determine which digit of the value the pointer is over and select that digit in step 4 . In another implementation of the method the widget may select the digit by the user clicking and dragging the pointer.
[0053] In step 5 the widget will highlight the digit selected.
[0054] The widget then hides the on-screen pointer from the user in step 6 . Other implementations may leave the pointer on-screen.
[0055] The widget waits until movement from the mouse is detected. If the mouse is moved left the value is decreased in step 7 by the magnitude of the selected digit. If the mouse is moved right the value is increased in step 8 by the magnitude of the selected digit. Other axes may be used and the orientation may be reversed.
[0056] Once the value has been changed the new value will be displayed in step 9 and the widget waits at step 6 for further movement. Each increment or decrement may correspond to a given displacement of the mouse so that the amount incremented or decremented is proportional to movement of the mouse. If the mouse button initially pressed is released in step 10 the widget will unselect the digit, redisplay the pointer and return to wait at step 2 until another digit is selected.
[0057] Other implementations of the method may select the digit by clicking—pressing and releasing—the mouse button in which case the digit may be unselected by clicking the button again.
[0058] [0058]FIG. 2 shows an example of one possible implementation of the method for controlling a field.
[0059] In the first step 12 the pointer is over the field and over the “2” digit within the value. In the second step 13 the “2” digit has been selected. This may have occurred by the pressing and holding down of a mouse button, by clicking a mouse button or by some other user action. The “2” digit has been highlighted as the selected digit by backlighting the digit in a different shade. The user now moves the mouse to the left by one increment.
[0060] The third step 14 shows the value as it has been changed. The digit “2” within the value “2786” has a magnitude of 1000. The original value, “2786”, has been changed by 1000. In this example, the mouse moving left decreases the value. The new value is “1786”. Movement of the mouse to the left by another increment will decrease the value to “786”.
[0061] [0061]FIG. 3 shows an example of one possible implementation of the method for controlling a first field and an associated second field.
[0062] In the first step 15 the pointer is over the first field and over the “7” digit within the value. In the second step 16 the “7” digit within the first field has been selected. This may have occurred by the pressing and holding down of a mouse button or by clicking a mouse button. The “7” digit is at magnitude 100 within the value. The “7” digit within the first field has been highlighted and the “0” digit corresponding to magnitude 100 in the second associated field has been highlighted.
[0063] The user then moves the mouse down by one increment and right by one increment.
[0064] The third step 17 shows the value of the first field and the value of the second field as they have been changed. The original value of the first field, “2786”, has been increased by 100 to “2886”. In this example, the movement of the mouse along the X axis changes the value of the first field and movement to the right increases this value.
[0065] In this example, movement of the mouse along the Y axis changes the value of the second field and movement downwards decreases this value. The original value, “4012”, less 100 results in a new value of “3912”.
[0066] [0066]FIG. 4 illustrates an example where there are three associated fields. All of the fields are spatial co-ordinates and represent the three axes of a 3-D environment.
[0067] This example is similar to the example given in FIG. 3. In this example the third z axis field is controlled by the scroll wheel on the mouse.
[0068] The scroll wheel is moved forward by one increment in the second step 19 . In this particular example movement of the scroll wheel forward increases the value of the field.
[0069] The value within the z axis field has changed in step 20 by increasing by 100—the magnitude of the selected digit.
[0070] It will be appreciated that there are mouse devices that exist with different mechanisms to control different axes of movement, such as mouse devices with two scroll wheels or built-in track-balls. It will be appreciated that such devices may increase the number of associated fields which may be controlled at one time.
[0071] In the examples given in FIGS. 3 and 4, the mouse device is being moved in all axes of movement. It will be appreciated that the mouse device may be moved only along one axis of movement. If the mouse device is moved along only one axis only the value within the field over which that axis of movement has control will change.
[0072] The method can be deployed on a standard personal computer with at least a processor, memory, a user input device, and an output device.
[0073] The present invention provides the advantage of coarse and fine control over a field. This advantage is beneficial for applications with fields with large ranges of values that are modified by user input. Such applications include three-dimensional modelling and animation software, where the fields can contain X and Y co-ordinates, or activation values. Activation values (including animation keyframes, which have a time value and an orthogonal value which is used to interpolate animation data between consecutive keyframes) are values which specify the activation conditions (including timing) for animation actions.
[0074] The present invention provides a simple user interface method and system to enable a user to change the value of a field, or the values of two or more associated fields, with a high degree of control and ease of use. The method and system is intuitive to users of pointer based graphical user interfaces and may be incorporated into existing applications with minimal or no alteration to existing visual components.
[0075] While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of applicant's general inventive concept.
|
The present invention relates to a field control method and system. More particularly the present invention relates to a method for changing the values of a field by use of a virtual slider. A value from a field is displayed on a display device ( 12 ). A digit of the value is selected in response to user input from a pointer device ( 13 ). The value is changed by the magnitude of the selected digit in response to user input from a pointer device ( 14 ). The invention may find particular application in graphical user interface systems. A field control user interface system is disclosed. A method and user interface system for controlling a field and one or more associated fields is also disclosed.
| 6
|
This is a continuation of application Ser. No. 850,953 filed Nov. 14, 1977, which is a continuation of application Ser. No. 751,607 filed Dec. 17, 1976, now abandoned, which is a continuation of application Ser. No. 652,802 filed Jan. 27, 1976, now abandoned, and which is a continuation of application Ser. No. 508,985 filed Sept. 25, 1974, now abandoned.
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates in general to the sport of ice skating and, more particularly, to a surface for such purpose.
Heretofore, the only suitable surfaces for ice skating have been those of refrigerated character, as well as naturally formed ice in ponds and the like. However, due to the expense of installation and maintenance, refrigerated ice skating surfaces have necessarily only found usage in urbanized areas providing a volume of admissions commensurate with the investment and expenses involved. Efforts to the present time to develop a non-refrigerated skating surface have consistently proved fruitless.
Therefore, it is an object of the present invention to provide a non-refrigerated surface suitable for accepting ice skates in a manner substantially equivalent to ice.
It is another object of the present invention to provide a skating surface which may be substantially preformed thereby obviating the necessity for costly installation services and permitting of the establishment of the surface for usage by relatively unskilled individuals.
It is a further object of the present invention to provide a skating surface of a non-refrigerated character which may be composed of a preselected number of integrated components thereby permitting of skating areas of predetermined extent so that the developed surface may accommodate the available space.
It is a further object of the present invention to provide a non-refrigerated skating surface which does not necessitate an especially prepared foundation but which may be readily laid out upon any flat, plane surface regardless of constitution; which is wear resistant; which may be most economically manufactured and maintained; and which may be utilized both outdoors and indoors.
It is a still further object of the present invention to provide a skating surface which may be disassembled and easily stored during any periods of disuse; as well as permitting of facile transportability of the same.
GENERAL STATEMENT OF THE INVENTION
It is within the contemplation of the present invention to provide a surface for use by ice skaters which is constituted of a multiplicity of interengaged flat components or units formed as by extrusion from resinous material. The said components being disposed upon a flat surface and with the upper face thereof being then treated with a lubricant, applied, as by spraying. The said lubricant may be applied periodically during the period of use of the surface, which latter has the desired extent of "give" or limited deformability to provide the users with substantially the same use characteristics and sensations as are encountered when skating upon a refrigerated, frozen surface.
DESCRIPTION OF THE INVENTION
By the present invention there is provided a skating surface comprised of a preselected number of discrete components, each being of like shape and size for economic production and with the same being of flat, sheet-like character having a thickness of approximately 1/4", and an area of any predetermined extent, desirably commensurate with ease of handling. Thus, in actual practice, such components have been of generally four-sided character and being of 1'×1' or 2'×2' dimensions, although obviously the generally square form is not critical. The edge portions of each component are of zig-zag or like alternating ridge and valley character for interlocking relationship with the confronting edge of the adjacent components for thereby developing the resultant surface.
It is to be understood that the aforesaid dimensions and thickness are preferred since the same conduce both to economy in production, as well as facile handling for shipping, storing, assembling and disassembling purposes.
The said components are formed by extrusion from high density polyethylene and may also be formed from polypropylene, as well as fluorinated polyethylene.
In developing the skating surface the said components may be disposed upon any suitable support area, whether the same be formed of wood, concrete, carpeting or the like; the only necessity being that the same be flat, in order that the skating surface will likewise be planar to assure of the absence of any unevenness, as well as appropriate interlock between the individual components.
Although it is evident that a skating surface of the type under discussion may be obtained from components having smooth, rectilinear edges, such has not been found preferable in practice since any contraction due to ambient conditions would tend to enlarge the joint between adjacent components and thus promote a skating hazard, while with the interlock as above described, separation of adjacent components by virtue of conditions causing contraction would be obviated.
After the components have been disposed upon the support area in surface formation there is applied upon the upwardly directed face of such surface a lubricant which comprises approximately one part by volume of a water soluble glycol and three parts by volume of water. Glycerin, or glycerol, has proved particularly suitable for formation of the lubricant, although other water soluble glycols, such as ethylene glycol, butylene glycol, propylene glycol, diethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, and the like are equally suitable. It is requisite that such compounds have a relatively high boiling point so as to avoid evaporation; be water soluble; provide the desired slickness to the surface treated, and possess the capacity for water retentivity. The lubricant, as stated, is applied preferably by spraying, as from a conventional spray gun, so as to form a mist which settled upon the surface of the components, with the spraying being desirably effected roughly one to two feet above the said surface. The lubricant will form a light film which serves to protect the surface against heating from the skate blades, as well as to protect the surface against cutting. Thus, the lubricant serves to dissipate the heat created by the friction developed between the blades and the surface.
The resultant surface has been found to very closely simmulate, from the standpoint of a skater, the properties of a refrigerated surface; with the same having been accorded a 90 percent efficiency in comparison. The resinous components possess the desired degree of "give" without being elastic so as to both resist the pressure of the skate blades to prevent damage, as well as to permit of a smooth skating or gliding action as provided by refrigerated surfaces.
Thus, the said material uniquely comprehends both the desired hardness, as well as the property of limited deformability. It is to be recognized that the lubricant is nontoxic and maintains the surface in a cool state, inhibiting undesired heat buildup.
The surface of the present invention may be utilized within an ambient temperature range of 40°-80° with about 60° being preferred. Consequently, the said surfaces are adaptable for indoor, as well as outdoor use, but with the latter being in seasons when ice skating is normally not provided.
Accordingly, in view of the foregoing, it is apparent that the present invention is indeed unique, providing a surface for ice skates which is both durable and economic and which does not require costly preparatory measure for installation so that the same can be used within any available area and within zones of limited population which have been unable heretofore to support a refrigerated surface.
|
A surface for ice skating purposes comprised of a multiplicity of discrete flat components formed of extruded resinous material with the same being edgewise interlocked. A lubricant of water and a glycol is applied to said surface for heat dissipation purposes, and promoting slickness.
| 2
|
[0001] The present invention relates generally to a manner by which efficiently to communicate packet formatted data in a packet radio communication system in which data is formatted at two or more logical layers, such as a TCP (Transport Control Protocol) layer positioned above an RLP (Radio Link Protocol) layer. More particularly, the present invention relates to apparatus, and an associated method, by which to alert an upper level logical layer of changes in loading, or other communication, conditions detectable at a lower level logical layer, thereby to permit the upper level logical layer to alter the amount, or rate, at which data is provided to the lower level logical layer.
[0002] Spurious communication timeouts are reduced as the upper level logical layer is made aware of the changing conditions, known at the lower level logical layer. And, the upper level logical layer provides data to the lower level logical layer at a rate appropriate to the communication conditions. When, for instance, supplemental channel (SCH) allocation to effectuate a data communication service in a CDMA2000 cellular communication system changes, the changed allocation is reported by the RLP layer to the TCP layer. And, the TCP window is altered, thereby to alter the amount of data provided by the TCP layer to the RLP layer within a designated time interval.
BACKGROUND OF THE INVENTION
[0003] The need to communicate is a regular aspect of many facets of modem society. Access to communication systems through which data is communicated is needed by many to provide and to receive conventional communication services. And, as advancements in communication technologies continue, new communication services, effectuated by improved communication systems, are likely to become available.
[0004] A communication system is formed of a set of communication stations including at least one sending station and at least one receiving station that are interconnected by way of a communication channel. Data sourced at a sending station is communicated upon a communication channel to a receiving station. If necessary, the sending station converts the data into a form to permit its communication upon the communication channel, and the receiving station converts the data received thereat into a form to permit the recovery of the informational content thereof.
[0005] A radio communication system is an exemplary type of communication system. The communication channel utilized upon which to communicate data between sending and receiving stations of a radio communication system is formed of a radio channel defined upon a radio air interface, a portion of the electromagnetic spectrum. Communication channels are otherwise generally defined in other communication systems upon conductive paths, i.e., wirelines, that interconnect the communication stations. By utilizing radio channels rather than channels formed upon wirelines, the wirelines that are otherwise required to interconnect the communication stations are obviated.
[0006] Because a wireline connection is not required to interconnect communication stations to communicate data therebetween, communication services are effectuable by way of a radio communication system when wireline connections interconnecting the locations at which the communication stations are positioned is not possible. Additionally, a radio communication system is available for implementation as a mobile communication system in which one or more of the communication stations is permitted mobility.
[0007] A cellular communication system is a mobile communication system. The networks of various cellular communication systems have been installed throughout significant portions of the populated areas of the world. Cellular communication systems are used to communicate telephonically to effectuate both voice and data communication services.
[0008] A user communicates by way of a cellular communication system through use of a mobile station. A mobile station is a radio transceiver that transceives data-containing communication signals with fixed-site transceivers that form parts of the network of the communication system. More generally, a mobile station, sometimes in conjunction with an additional device, is referred to as user equipment (UE). The fixed-site transceivers are referred to as base stations. The base stations are installed at spaced-apart locations throughout the geographical areas encompassed by the network of the communication system. The base stations each define a cell that represents a coverage area encompassed by the base station that defines the cell.
[0009] Communications by a mobile station, when positioned within a cell defined by a particular base station, generally communicates with that base station. Due to the inherent mobility of a mobile station, the mobile station might travel between cells defined by successive ones of the base stations. Continued communications with the mobile station are permitted through the effectuation of communication handoffs between successive ones of the base stations associated with the cells through which the mobile station passes.
[0010] First-installed cellular communication systems, referred to as first-generation systems, utilize analog communication techniques. So-called second-generation communication systems utilize digital communication techniques and provide limited data communication services. And, third-generation systems, are presently undergoing deployment. Third-generation systems provide for high-speed, variable rate data communication services.
[0011] An exemplary third-generation cellular communication system operates pursuant to the operating protocol set forth in a CDMA2000 operating specification. Packet-based communication services, and the operating protocols for effectuating such services, are set forth in the operating specification.
[0012] Various technology proposals by which to effectuate communication of packet data at high data rates in a CDMA2000 system have been proposed. The 1xEV-DV data communication service is one such proposal. Other data communication services are also proposed. Channels defined in a CDMA2000 system, as well as other code-division, multiple-access systems, are based upon codes by which communication data is coded. The code forms a spreading code that spreads data that is to be communicated from a low data rate to a spreading rate of 1.2288 Mcps. Codes assigned to communicate different concurrently-communicated data are orthogonal to one another to provide channel separation.
[0013] High data rate channels permit data to be communicated at high data rates and use proportionally more power for their transmission. Generally, this is achieved through the assignation of multiple orthogonal codes to a single communication session so that the throughput is the sum of all the related orthogonal channels assigned to the communication session. The number of orthogonal codes that are available by which to code data is limited. As the number of communication sessions increases, assignment of the codes must be controlled to allocate communication resources in a desired manner. Assignment of multiple orthogonal codes maps to so-called, 2×, 4×, 8×, or 16× supplemental channel assignments upon which high data rate communication services are effectuated.
[0014] When a cell is relatively unloaded, a communication allocation can be granted to a mobile station to effectuate the communication service at a high rate, such as through allocation of a 16× supplemental channel upon which to communicate the data to effectuate the communication service. When such a grant is made, an RLP (Radio Link Protocol) logical layer is permitted to send increased amounts of data on the radio air interface extending between the mobile station and the base station. And, accordingly, the TCP-layer (Transport Control Protocol-layer) window size is correspondingly sized.
[0015] However, in the event that loading conditions in the cell increase, i.e., the 16× supplemental channel assignment is reduced, e.g., to a 2× supplemental channel assignment. Reduced amount of data is communicated at the RLP layer. However, conventionally, the TCP layer is not made aware of the changed allocation. And, the TCP layer remains at a correspondingly large window size, and TCP-layer data is attempted to be communicated at the higher rate. TCP layer timeouts occur as a result. But, such timeouts are essentially spurious as the data is not actually sent out at the RLP layer. Analogous problems occur as a result of changing FER (Frame Error Rate) conditions that result in lower supplemental channel assignments. The spurious timeouts adversely affect the efficiency at which the data is communicated and the time period required to complete the communication service.
[0016] If a manner could be provided by which to reduce the occurrence of spurious timeouts, as a result of changes in loading conditions, improved communications would result.
[0017] It is in light of this background information related to communications in a packet radio communication system that the significant improvements of the present invention have evolved.
SUMMARY OF THE INVENTION
[0018] The present invention, accordingly, advantageously provides apparatus, and an associated method, by which efficiently to communicate packet formatted data in a packet radio communication system in which data is formatted at two or more logical layers, such as a transport control protocol (TCP) layer positioned above a radio link protocol (RLP) layer.
[0019] Through operation of an embodiment of the present invention, a manner is provided by which to alert the TCP, or other upper-level logical layer of changes in loading, or other communication, conditions detectable at the RLP, or other lower-level, logical layer, thereby to permit the amount, or rate, at which data is provided by the upper logical layer to the lower logical layer.
[0020] Because the data provided by the upper level layer to the lower level layer is provided at a rate better matched to the rate at which the data is communicated by a communication station upon a radio link, spurious communication timeouts at the upper level logical layer are less likely to occur.
[0021] The lower level logical layer is notified, or otherwise alerted, to the channel allocation of channel capacity upon which to communicate data at the lower level logical layer. Responsive to notification of the lower layer logical level of the communication allocation, the lower level logical layer generates an indication of the allocation and provides the indication to the upper level logical layer.
[0022] The upper level logical layer includes a detector for detecting the indication generated at the lower level logical layer and, responsive thereto, changes are made at the upper level logical layer of the amount, or rate, at which data is provided to the lower level logical layer to be communicated therefrom. Thereby, the upper level logical layer is made aware of the communication allocations available at the lower level logical layer upon which to communicate data. Improved communication efficiency results as the data formed at the upper level logical layer is applied to the lower level logical layer at a rate that matches the capability of the data to be communicated from the lower level logical layer.
[0023] When the communication station forms a mobile station operable in a CDMA2000, or other, communication system in which data services are provided at a selectable, variable rate, improved communications are possible. When data is to be communicated by the mobile station, the mobile station generates a request of the network for channel capacity upon which to communicate the data. Depending upon, e.g., loading conditions, the network grants channel allocations to the mobile station to communicate the data. When the communication conditions are relatively unloaded, the allocation granted to the mobile station is relatively large. And, conversely, during relatively high loading conditions in the network, a correspondingly smaller allocation is granted to the mobile station.
[0024] The channel allocations are dynamic; that is to say, the allocations are changeable as loading conditions at the network change. For instance, if a request for allocation is made when network conditions are relatively unloaded, a relatively large allocation is granted to the mobile station. But, during effectuation of the communication of the data, the loading conditions change, and the allocation to the mobile station is susceptible to decrease. If the allocation is decreased, the rate at which data is communicated by the mobile station is correspondingly reduced. The allocations and reallocations are provided to an RLP logical layer of the mobile station.
[0025] A detector is functionally operable to detect the allocations and reallocations granted by the network. And, responsive to the detections, the RLP layer also includes an indication generator functionally operable to generate an indication that is provided to the TCP layer of the mobile station to alert the TCP layer of the allocation, or its change. A detector functionally embodied at the TCP layer detects the indications provided thereto by the RLP layer. And, responsive to detection of the indications, the size of the TCP window that is determinative of the amount or rate at which data is provided by the TCP layer to the RLP layer is correspondingly altered. By matching the amount of, and the rate at which, data is delivered to the RLP layer from the TCP layer, with the rate at which data is able to be communicated by the RLP layer, spurious timeouts are less likely to occur.
[0026] In these and other aspects, therefore, apparatus, and an associated method, is provided for a communication station operable in a packet communication system to communicate packet data. The communication station is defined in terms of logical layers having at least one mid-stack layer and at least one upper-level layer positioned thereabove. Communication of the packet data is facilitated. A detector is embodied at the mid-stack layer. The detector detects channel allocations allocated to the communication station to communicate the packet data. And, a reporter is embodied at the mid-stack layer and coupled to the detector. The reporter reports at least changes of the channel allocations detected by the detector to the upper level layer.
[0027] A more complete appreciation of the present invention and the scope thereof can be obtained from the accompanying drawings that are briefly summarized below, the following detailed description of the presently-preferred embodiments of the present invention, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 illustrates a functional block diagram of an exemplary radio communication system in which an embodiment of the present invention is embodied.
[0029] FIG. 2 illustrates a logical layer representation of a portion of the radio communication system shown in FIG. 1 including the functional entities that form an embodiment of the present invention.
[0030] FIG. 3 illustrates a message sequence diagram representative of signaling generated during operation of an embodiment of the present invention.
[0031] FIG. 4 illustrates a method flow diagram listing the method steps of the method of operation of an embodiment of the present invention.
DETAILED DESCRIPTION
[0032] Referring first to FIG. 1 , a radio communication system, shown generally at 10 , provides for the effectuation of radio communication services. Communication services are provided by, and to, mobile stations, of which a single mobile station 12 is shown in FIG. 1 . In the exemplary implementation, the radio communication system forms a cellular communication system operable generally pursuant to the operating protocols defined in a CDMA2000 operating specification.
[0033] The communication system provides for high data rate communication services, e.g., pursuant to an 1xRTT communication scheme or pursuant to a 1xEV-DV communication scheme. Each of such communication schemes provides for communication of data at high, and selectable, data rates.
[0034] While the following description of operation of an exemplary embodiment of the present invention shall describe its implementation in a CDMA2000-compliant, cellular communication system that provides for the high data rate communication services, the teachings of the present invention are implementable in other cellular, and other, communication systems.
[0035] The mobile station 12 communicates by way of radio communication channels formed between the mobile station and a network part of the communication system. The radio channels are defined upon the radio air interface formed upon the frequency bandwidth allocated for radio communications in the CDMA2000 communication system by appropriate regulatory bodies. The arrow 14 is here representative of radio channels defined upon the radio air interface. Various signaling and traffic channels are defined upon the radio air interface, of characteristics and used for purposes, set forth in the CDMA operating specification. Forward-link channels are defined upon which to communicate data originated at the network part of the communication system to the mobile station.
[0036] Various functional entities of the network of the radio communication system are shown in the figure. An exemplary base transceiver station (BTS) forms part of the network of the radio communication system. The base transceiver station comprises radio transceiver circuitry for transceiving data communicated on forward- and reverse-link channels defined upon the radio air interface.
[0037] The base transceiver station defines a coverage area, referred to as a cell. When a mobile station, such as the mobile station 12 , is positioned within the cell defined by a particular base transceiver station, such as the base transceiver station 18 , the mobile station generally communicates with the base transceiver station in whose cell that the mobile station is positioned. As the mobile station travels through successive cells defined by successive base transceiver stations, handoff procedures are performed to permit continued communications with the mobile station with successive ones of the base transceiver stations.
[0038] The base transceiver station is coupled to a control device, here a radio network controller (RNC) 22 . The radio network controller controls operation of base transceiver stations, such as the base transceiver station 18 , including communication operations during which the base transceiver station communicates with mobile stations within its coverage area. The radio network controller, in turn, is coupled to a radio gateway (GWY) 24 .
[0039] The gateway connects radio-network entities, here formed of the radio network controller and base transceiver station, with an external network. Here, the external network forms a packet data network (PDN) 28 . Correspondent entities, such as the correspondent entity (CE) 34 , are coupled to the packet data network. The correspondent entity 34 is representative of a correspondent node forming a data source or data sink at which data is sourced or terminated during a communication session with the mobile station 12 .
[0040] The data communicated between the correspondent entity and the mobile station comprises, for instance, data communicated pursuant to a high data rate communication service, such as a 1xEV-DV data communication service or a 1xRTT data communication service. A data communication service is initiated by either a correspondent entity or by a mobile station. Here, for instance, a data communication service is initiated by the mobile station 12 for delivery to the correspondent entity 34 .
[0041] When the data communication service is to be initiated, the mobile station sends a request to the network part of the communication system to request allocation of communication capacity on the radio air interface to permit the data to be communicated thereon to effectuate the data communication service. While communication capacity must be available in the network by which to route the data therethrough to deliver the data to the correspondent entity, bandwidth limitations are not regularly as severe at the network part of the communication system, and allocation of communication capacity therein is less problematical than the allocation of communication capacity by way of the radio air interface.
[0042] Communication capacity allocation allocated to the mobile station to effectuate the communication of the data pursuant to the high data rate communication service is dependent on various factors, including the loading in the cell. That is to say, other communications in the cell or reservations for communication capacity for other mobile stations pursuant to other communication sessions, are at least in part determinative of the allocations that are made to a particular mobile station to effectuate a data communication service. Additionally, loading conditions in a cell are not constant and dynamically change. As loading conditions change, communication capacity available to effectuate the data communication service also change.
[0043] In a CDMA2000 communication system, a supplemental channel is defined. And, 2×, 4×, 8×, and 16× SCH (Supplemental Channel) allocations are made, depending upon loading conditions in the cell when the request is made. And, after an allocation is made, reallocations are made, if needed, as a result of changing loading conditions.
[0044] Conventionally, communication capacity reallocations are made known to a RLP (Radio Link Protocol) layer of the mobile station. But, indications of reallocation of the communication capacity are not delivered by the RLP layer to layers positioned thereabove, such as the TCP layer. As a result, the upper level logical layers are not made aware of changes in communication capacity available to the mobile station to communicate data to effectuate the data communication service. And, the upper level logical layers continue to provide data at a rate corresponding to an earlier-allocated level of communication resources to the RLP layer. Because the RLP layer, however, communicates the data at a rate corresponding to the allocated communication capacity, data back-ups result in the event that the allocated communication capacity is decreased. Spurious timeouts at the TCP layer occur as a retransmission of a complete congestion window size of data into the network occurs.
[0045] The mobile station 12 further includes apparatus 42 of an embodiment of the present invention that, through its operation, facilitates a reduction in the number of spurious timeouts that occur as a result of changes in communication allocations to the mobile station during effectuation of the communication service. The apparatus 42 detects, or otherwise is made aware of, the allocations of communication resources provided to the mobile station to effectuate a communication service. Changes in such allocations are also detected or made known. In turn, notification is made to the TCP or other upper level logical layer of the change in allocation of communication capacity allocated to the mobile station to effectuate the data communication service. And, responsive thereto, changes are made at the upper level logical layer in the rate at which data is provided to the RLP layer. As the detections are dynamically made and the reports of the changes to the allocations are dynamically made to the upper level logical layer, dynamic changes in the rate at which the data is provided from the upper level logical layer to the lower level logical layer is possible. Spurious timeouts are less likely to occur, and improved communications result.
[0046] FIG. 2 again illustrates the mobile station 12 that forms a portion of the radio communication system 10 shown in FIG. 1 . Here, the mobile station is represented in logical layer form. That is to say, the mobile station is here shown to include an RLP (Radio Link Protocol) layer 48 and a TCP (Transport Control Protocol) layer 52 positioned thereabove. Logical layers formed beneath and above the RLP and TCP layers, respectively, are not separately illustrated, for purposes of simplicity. The apparatus 42 is also again shown. Here, the apparatus 42 is shown to be formed of functional entities, implemented at one of the RLP and TCP layers. The functions provided by such functional entities are implementable in any desired manner, such as by algorithms executable by processing circuitry.
[0047] Here, the apparatus includes a detector 56 . The detector 56 operates to detect grants of communication capacity allocations to the mobile station to communicate by way of radio channels, here reverse-link channels with the network part of the communication system. And, as reallocations of the channel capacity are made, the detector also detects such reallocations. The RLP layer, a mid-stack layer, also includes a reporter 58 . The reporter is coupled to receive indications of detections made by the detector. The reporter generates a report that is communicated to the TCP layer 52 . And, the TCP layer includes a selector 62 that operates to select the packet sizes of TCP-formatted packets formed at the TCP layer. As channel allocations change, the detector detects the changes, and the reporter generates indications of the changes. Responsive thereto, the selector 62 operates to alter its selection of the packet sizes of the TCP-formatted packets that are to be formed at the TCP layer and provided to the RLP layer.
[0048] Here, additionally, the apparatus includes a TCP packet formatter 64 that is coupled to the selector 62 to receive indications of the packet size selections made thereat.
[0049] Thereby, through operation of the apparatus 42 , changes in load conditions are deduced at the RLP layer based upon, e.g., detection of supplemental channel assignment changes. And, the detected changes are passed on to the TCP layer. Once delivered to the TCP layer, the sending window of the TCP layer is adjusted to be in accordance with the supplemental channel allocation. Analogous operation is performed when the supplemental channel assignments are changed due to changing FER (Frame Error Rate) conditions.
[0050] In other words, the interface between the TCP and RLP layers at the mobile station, or other sending station, is enhanced. When the RLP layer receives supplemental channel assignments that result in changes to the supplemental channel assignments or the supplemental channel being taken away, the RLP layer sends the indications to the TCP layer over the enhanced interface. The TCP layer then adjusts the window size such that proportionately lesser amounts of data are sent over to the RLP layer.
[0051] FIG. 3 illustrates a message sequence diagram, shown generally at 72 , representative of signaling generated during operation of the radio communication system shown in FIG. 1 . First, and as indicated by the segment 74 , when a communication service is to be effectuated by the mobile station, the mobile station generates a request for channel capacity allocation to the network, here represented by the base transceiver station/radio network controller 18 / 22 . And, responsive to the request for channel allocation, an allocation grant is generated, and returned, indicated by the segment 76 to the RLP layer of the mobile station. Detection is made at the RLP layer and a report is generated and provided, here indicated by the segment 78 , to the TCP layer. When delivered to the TCP layer, a TCP window size is selected, indicated by the block 82 . And, effectuation of the communication service commences, here indicated by the block 84 .
[0052] Subsequently, in the event that loading conditions change, the network reallocates the communication capacity allocated to the mobile station and notifies the mobile station, here indicated by the segment 86 , of the changed allocation. In turn, the RLP layer of the mobile station forms a report and provides the report, indicated by the segment 88 , to the TCP layer. At the TCP layer, the TCP window size is reselected, indicated by the block 92 , and communication operations continue. As the TCP window size is resized corresponding to the changed allocation of communication capacity granted to the mobile station, the rate at which data is provided by the TCP layer to the RLP layer is meshed with the communication capacity on the radio air interface upon which data is subsequently communicated. Spurious timeouts are less likely to occur.
[0053] FIG. 4 illustrates a method flow diagram 102 illustrating the method steps of the method of operation of an embodiment of the present invention. The method facilitates communication of packet data in a packet communication system by a communication station that includes a mid-stack logical layer and an upper-logical layer positioned thereabove.
[0054] First, and as indicated by the block 104 , channel allocations allocated to the communication station to communicate packet data is detected at the mid-stack layer. Then, and as indicated by the block 106 , a report is made to the upper level logical layer of at least changes of the channel allocations detected at the mid-stack logical layer. Thereafter, and as indicated by the block 108 , selection is made at the upper level logical layer of desired packet sizes of packets that are to be delivered by the upper level logical layer to the mid-stack logical layer.
[0055] By better matching the upper level packet size, and rate at which data is provided to the mid-stack layer, spurious timeouts resulting from decreased channel allocations on a radio air interface upon which to communicate the data are less likely to occur.
[0056] The previous descriptions are of preferred examples for implementing the invention, and the scope of the invention should not necessarily be limited by this description. The scope of the present invention is defined by the following claims.
|
Apparatus, and an associated method, for facilitating communication of data in a packet radio communication system to effectuate a packet communication service in which packet data is communicated at a variable, selectable rate. A detector embodied at an RLP layer detects channel allocations and channel reaollcations, granted to the mobile station to effectuate the data communication service. A report is generated at the RLP layer and forwarded to the TCP layer. At the TCP layer, selection is made of the TCP window to match the rate at which data is provided to the RLP layer to the rate, based upon the channel allocations provided to the mobile station, at which the data is communicated therefrom.
| 7
|
BACKGROUND OF THE INVENTION
This invention relates to a system for modifying the environment in a personal work station area and in particular to a system for providing task lighting and air circulation for such a work station. While the invention is primarily intended for use with a computer work station, including a video display terminal, it may find application in other work station settings.
Computer work stations typically provide an environment that contributes to fatigue of the operator One of the most difficult environmental factors to regulate in a computer work station is task lighting. Lighting that may be appropriate for typical desk work is wholly inappropriate for a video display terminal (VDT) operator. Variations in the contrast between the VDT brightness and illumination of the reference copy materials creates eyestrain. Glare, which is undesirable in any environment, is especially fatiguing in the context of a VDT work station.
Characteristically, the conventional computer work station is provided in the form of a cubicle having walls extending, partially or fully, from the floor to the ceiling. Such cubicles tend to be installed subsequent to the design of the larger room in which they are placed and the lighting in the ceiling grid is usually not matched to the location of the work station cubicle. Thus, contrast variations between the VDT and the reference copy materials, as well as shadows that are cast across both the VDT and the reference copy materials, are aggravated by the use of paneled cubicles.
An additional difficulty created by cubicle work stations is the interference caused by the paneled walls, with the natural air circulation in the larger room in which the cubicle is positioned. The paneled walls block the natural air flow and tend to trap heat generated by the computer system. The environment of the computer work station is thus further degraded by inadequate air circulation and a buildup of heat.
While attempts have been made to improve these factors tending to degrade the work station environment, most such attempts have had serious drawbacks. Various task lighting devices have been proposed. Most such devices, however, take up premium work space within the human reach zone of the work station. Those devices that may be remotely located, tend to create fatigue-generating glare because of compromises resulting from the remote location. While attempts have been made to provide a light source that allows adjustment of the direction of the light, and/or the intensity of the light, one variable is usually dependent upon the other. The usual result is that either light intensity is improper or glare is produced. Additionally, the proposed prior art devices have not addressed the problem of inadequate air circulation and a buildup of heat, generated by the computer equipment, in the work station environment. Accordingly, it is the object of the present invention to provide a solution to such environmental problems present in the personal work station.
SUMMARY OF THE INVENTION
The above difficulties are overcome by the present invention which provides an apparatus for modifying the environment in a work area. The apparatus includes means for transmitting energy in a first medium, such as visible light, in a given direction and second means for transmitting energy in a second medium, such as air, in the same direction. First deflection means is provided, spaced from the first energy transmission means in the direction of energy transmission, and capable of deflecting the first medium. The invention further provides second deflecting means, spaced from the second energy transmission means and positioned between the first energy transmission means and the first deflecting means. The second deflecting means is capable of deflecting the second medium and passing the first medium. In this manner, both energy transmission means and both deflecting means may be aligned along an axis, with the first medium passing through the second deflecting means to be deflected by the first deflecting means and the second medium being deflected by the second deflecting means. Thus, independent control of the first and second mediums is provided in a compact unit that may be positioned remotely of the human reach zone in a work station.
These and other related objects, advantages and features of this invention will become apparent upon review of the following specification in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a work station environmental system according to the invention;
FIG. 2 is a sectional view taken along the lines II--II in FIG. 1; and
FIG. 3 is an enlarged partial plan view taken along the lines III--III in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now specifically to the drawings and the illustrative embodiments depicted therein, a work station environmental system, generally shown at 10, includes as base unit 12, a support member 14 extending upwardly from base 12 and first and second deflecting members 16 and 18, respectively, attached to support member 14.
Base unit 12 includes a unidirectional light source 20 and an air moving fan 22 positioned within a housing 24. Housing 24 includes a recessed flange portion 26 on a top wall thereof. Flange 26 is circular in configuration and includes edge means for defining a circular opening 28 in the housing. A donut-shaped screen member 30 is supported in opening 28 by flange 26 and includes a central opening 32 having the diameter of light source 20 and which is aligned with the light source. A cylindrically-shaped light shade 34 surrounds light source 20 and is supported by screen member 30.
Light source 20, in a preferred embodiment, includes a quartz bulb 36 surrounded by a reflector 38 for directing the light generated by bulb 36 unidirectionally along a vertical axis designated A. The bulb and reflector are commercially available as a combined unit manufactured by the General Electric Company under Model Q42MR16/VNSP (EZY). Such a unit is powered by a 12 volt DC power supply 40. The voltage provided from power supply 40 to bulb 36 may be varied by a rheostat (not shown) in order to provide intensity adjustment for the light source. Air flow fan 22 is, in a preferred embodiment, a 27 cubic foot per minute high-speed fan that is commercially available and sold by the Radio Shack Corporation under Catalog No. 273-243A. In the preferred embodiment, air flow fan 22 is energized by a 120 volt AC power source, such as conventional house power. It is to be understood that light source 20 may alternatively be configured to be supplied by a 120 volt AC power source and air moving fan 22 may alternatively be energized by 12 volt DC power supply 40 through a speed-adjusting rheostate. A connector 42 attached to a non-rotating portion of fan 22 provides electrical connections to bulb 36 from power source 40. Air moving fan 22 is positioned within housing 24 in a manner to unidirectionally move a stream of air along axis A, i.e., coaxially with the unidirectional light beam generated by light source 20.
Accordingly, energy is transmitted vertically along axis A in two media: by radiation in the visible light spectrum from light source 20 and pneumatically by air flow directed through screen member 30 from fan 22. The vertically ascending light beam and air stream encounter first deflecting member 16, which is configured to transmit the light beam therethrough into contact with second deflecting member 18. Deflecting member 16 is sufficiently imperforate, however, to deflect a significant amount of the air stream away from the surface of deflecting member 16 at the angle of incidence of the air stream. Second member 18 includes a light reflecting surface 44, such that the light beam transmitted through member 16 is deflected at the angle of incidence from member 18 by surface 44.
In a preferred embodiment, first deflecting member 16 is a transparent planar plexiglass member mounted to support member 14 by adjustable mounting means 46. In this preferred embodiment, second deflecting member 18 is a planar plexiglass member having a mirrored surface 44 for deflecting the light beam and is attached to support member 14 by another adjustable mounting means 46.
Mounting means 46 includes a forked bracket member 48 having a pair of fingers 50 (only one of which is illustrated) spaced-apart the thickness of the respective deflecting member (FIG. 3). A ball 52 is engaged with a mating socket within bracket member 48 and includes a threaded shaft 54 extending through a slotted opening 56 in support member 14 and threadably engaged by an adjusting knob 58.
With adjusting knob 58 loosened, shaft 54, and hence the respective deflection member, may be longitudinally positioned along support member 14. Additionally, the resulting clearance between ball 52 and its mating socket (not shown) provides means for adjusting the angular orientation of the respective deflecting member with respect to axis A. The deflecting member may be angularly adjusted in mutually perpendicular planes extending laterally and longitudinally through system 10. This allows the deflecting members 16 and 18 to be independently pivoted relatively upwardly or downwardly and laterally from side-to-side with respect to support member 14. By adjusting deflecting member 16, the air stream exiting base unit 12 may be substantially deflected laterally at a desired angle to one side or the other, or towards the forward portion of the unit, away from support member 14 or any combination of directions. Likewise, by adjusting the angular orientation of second deflecting member 18, the light beam reflected therefrom may be directed laterally at a desired angle to one side or the other or may be directed forwardly or a combination of directions. By adjusting the longitudinal positions of deflecting members 16 and 18 along support member 14, the size of the light spot produced on the work surface by the light beam may be increased or decreased and the relative density of the air stream increased or decreased. While longitudinal adjustment of the deflecting members 16 and 18 may additionally provide a degree of adjustment of the intensity of the light and air reaching the desired targets, in the preferred embodiment the intensities are controlled by varying the voltage from power source 40 to the respective light source 20 and air moving fan 22.
The present invention is thus seen to provide a compact unit that provides a unique solution to two difficult environmental problems. The unit is not only compact and requires little support room, but may be positioned remotely of the human reach zone. The ability to independently direct, focus and adjust the intensity of the light source enhances the ability of the invention to reduce the production of unwanted glare and to produce a balance in contrast between the VDT screen and the work copy.
Changes and modifications in the specifically described embodiments can be carried out without departing from the principles of the invention which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law, including the doctrine of equivalents.
|
A compact system provides task lighting and ventilation assistance for a personal work station. The system includes a unidirectional light source and air moving fan positioned to coaxially, upwardly transmit a light beam and air stream. First and second deflection members are positioned along the axis in the path of the light and air. The lower deflection member transmits the light beam therethrough to the upper deflection member and deflects the air stream in an adjustable direction. The upper deflection member deflects the light beam in an independently adjustable direction.
| 5
|
FIELD OF THE INVENTION
[0001] The following invention relates generally to instrumentalities and methodologies in blood component separation. More specifically, the instant invention is directed to a method and apparatus for collecting a blood sample and subsequently separating the collected sample into constituent blood components for individual storage or use.
BACKGROUND OF THE INVENTION
[0002] Blood collection is always important, particularly in times of emergency (immediate use), but whole blood may only be stored for about 30 days before it is “outdated”. For long term storage, the ability to separate the whole blood into its major components (white blood cells, platelets, red blood cells and plasma) is of paramount importance because the long term storage condition for each component is different in terms of temperature and storage media. The most important component separations occurring after collection is the separation of red blood cells (RBC), white blood cells (WBC), platelets, and plasma from one another. Within the WBC it is sometimes important to separate the granulocytes from the lymphocytes and monocytes. After separation and extraction of particular components, a fraction of the blood may be returned to the patient.
[0003] It is possible to separate the various components of whole blood either under or after centrifugation, due to their differing densities. Some prior art methods, such as that in U.S. Pat. No. 4,120,448, utilize a chamber connected to a centrifuge. The centrifuged blood separates in the chamber, and a plurality of collection means are positioned at various locations in the chamber corresponding to the areas where each component congregates, which is density-dependent.
[0004] The present (prior art) technique for sequestering white blood cells from whole blood: requires skilled technicians, is labor intensive in that it requires 16 steps conducted over the span of one hour, and produces inconsistent results because of the requirements placed on the technician in the exercise of technique. Most significantly, however, the 16 step present technique is “open”; that is, the blood product is processed in a manner that does not maintain the sterility of the product because the need to obtain samples or add sedimenting agents or cryoprotectants at the various stages of production can not be accomplished with allowing the outside environment access to the interior, meaning potential contamination of the product:
[0005] The 16 steps are:
[0006] 1. Collect placental blood into collection bag (range 60-200 ml).
[0007] 2. Add HES to collection bag (20% v/v).
[0008] 3. Load collection bag into special centrifuge cup supports.
[0009] 4. Centrifuge at 50 G for 13 min. to raise WBC from RBC (up to 6 units at one time).
[0010] 5. Spike or sterile dock collection bag to expressor and processing bag set to scale.
[0011] 6. Gently transfer collection bag to expressor and processing bag set to scale.
[0012] 7. Express off WBC rich plasma and 10-15 ml of the top layer of RBC into processing bag—leaving excess RBC.
[0013] 8. Remove collection bag with excess RBC.
[0014] 9. Load processing bag set in special centrifuge cup supports.
[0015] 10. Centrifuge processing bag set at 400 G for 10 min. (up to 6 units at one time).
[0016] 11. Gently transfer processing bag to expressor.
[0017] 12. Express off excess plasma leaving 20 ml WBC concentrate.
[0018] 13. Remove excess plasma bag from processing set.
[0019] 14. Add 5 ml cryoprotectant to WBC in processing bag at 4° C.
[0020] 15. Transfer cryoprotected WBC to freezing bag.
[0021] 16. Tube seal and separate freezing bag from processing bag.
[0022] The following prior art reflects the state of the art of which applicant is aware and is included herewith to discharge applicant's acknowledged duty to disclose relevant prior art. It is stipulated, however, that none of these references teach singly nor render obvious when considered in any conceivable combination the nexus of the instant invention as disclosed in greater detail hereinafter and as particularly claimed.
[0000]
PATENT NO.
ISSUE DATE
INVENTOR
4,120,448
Oct. 17, 1978
Cullis
4,720,284
Jan. 19, 1988
McCarty
Des. 314,824
Feb. 19, 1991
Moon
5,674,173
Oct. 7, 1997
Hlavinka et al.
5,723,050
Mar. 3, 1998
Unger et al.
5,792,038
Aug. 11, 1998
Hlavinka
5,921,950
Jul. 13, 1999
Toavs et al.
6,315,706
Nov. 13, 2001
Unger et al.
6,348,031
Feb. 19, 2002
Unger et al.
6,652,475
Nov. 25, 2003
Sahines et al.
WO95/01842
Published: Jan. 15, 1995
Unger
[0023] The prior art references listed above but not specifically described teach other devices for blood processing and further catalog the prior art of which the applicant is aware. These references diverge even more starkly from the reference specifically distinguished above.
SUMMARY OF THE INVENTION
[0024] The present invention comprises a bag set that may be used to collect a whole blood sample from a source. Most significantly, the bag set defines a closed system in that once the blood is introduced, processing can occur outside a clean room or away from a sterile hood because access to any pathogens in the exterior environment is prevented. The bag set is then placed into a centrifuge for component separation. The whole blood processing bag, which may contain an anticoagulant such as CPD, ACD or CPD-A, contains at least one inlet and one outlet port connected to a plurality of component bags. The processing bag may optionally contain a sedimenting aid such as HES, but, unlike the prior art, such sedimenting aid is not required. Each component bag has a separate line leading from the whole blood processing bag, and each line can be clamped, tube-sealed and separated from the whole blood processing bag once a particular component bag has been filled.
[0025] In practice, the blood is collected and directed into an inlet port on the whole blood processing bag and the input line is clamped, sealed off, and separated from the whole blood processing bag. The whole blood processing bag, which is asymmetrically shaped, hangs in a bag set holder having a complementally shaped opening that closely contacts the bag at the bottom end, and an exterior of the bag set holder is adapted to fit in a conventional centrifuge cup or socket. The centrifuge is operated at varying G-forces to optimally separate the components. Once the components are separated by density in the whole blood processing bag, a servo motor is engaged to open a metering valve on the line leading from the processing bag to a bag that will contain the densest component. This allows the densest component to fill its particular storage bag, usually under centrifugation.
[0026] Applicant's process can be summarized in the following 7 or 8 steps which are performed over a span of 25 minutes, resulting in repeatable yields in excess of 90% of the lymphocytes and monocytes.
[0027] 1. Collect placental blood into collection bag (range 60-200 ml).
[0028] 2. Spike or sterile dock collection bag to bag processing set and transfer blood to processing bag.
[0029] 3. Add HES to processing bag (20% v/v). (Optional)
[0030] 4. Load processing bag set onto auto expresser.
[0031] 5. Centrifuge at an uninterrupted Run at two different speeds: 1,400 G for 20 min. to segregate WBC at RBC/plasma interface and 85 G for 5 min. to express the RBC to the RBC bag and WBC to freezing bag.
[0032] 6. Tube seal and separate excess RBC and plasma bags from processing set.
[0033] 7. Add 5 ml cryoprotectant to WBC in freezing bag at 4° C.
[0034] 8. Tube seal and separate freezing bag from cryoprotectant line.
[0035] Complete collection of the first component is indicated preferably by an optical sensor that is present in the bag set holder device. The servo motor, directed by the sensor, automatically closes the metering valve on the line, terminating collection of that particular component. The servo motor then further engages the metering valve to allow collection of the next component through a second output line connecting the metering valve and the second storage bag. The process may sequentially continue until all desired components are collected in separate storage bags: red blood cells, white blood cells (lymphocytes and granulocytes), platelets, and plasma. If so desired, multiple components, such as the white blood cells and the platelets can be directed to the same storage bag. The sensor may be other than optical. For example, the sensor may monitor changes in electrical characteristics inherent in differing densities, such as capacitance, viewing the fluid as a dielectric. Commercially available markers (e.g. monoclonal antibodies, polarized particles, magnetic density, or fluorescence markers, etc.) can be introduced into the blood and monitored.
[0036] The bags receiving fluid components may also be supported for weighing both during centrifugation and when at rest. Accurate separation occurs.
[0037] Once collected, each storage bag may be sealed off and separated from the whole blood processing bag. Any necessary preservatives or additives may be introduced through the collection lines before processing or storing.
OBJECTS OF THE INVENTION
[0038] Accordingly, it is a primary object of the present invention to provide a new and novel device and method for separating the components of whole blood for subsequent storage or use.
[0039] It is a further object of the present invention to provide a device and method as characterized above in which separation may be accomplished entirely by machine during a single uninterrupted centrifugation run without the considerable handling between multiple centrifugation runs typically practiced in a blood bank with conventional means of separating blood components.
[0040] A further object is to precisely sequester red blood cells, plasma, platelets and white blood cells even separating within white blood cell populations.
[0041] It is a further object of the present invention to provide a device and method as characterized above in which the separation apparatus is self-contained to simplify the operation.
[0042] Viewed from a first vantage point, it is an object of the present invention to provide a device for sequestering components from whole blood, comprising, in combination: a bag set, said bag set including a first bag and plural other bags; a bag set holder, whereupon the first bag is contained within an interior portion of the bag set holder, and the plural other bags are located at an elevation lower than said first bag; and a centrifuge having at least two diametrically opposed receiving sockets, at least one socket dimensioned to receive the bag set holder.
[0043] Viewed from a second vantage point, it is an object of the present invention to provide an apparatus for use with a conventional centrifuge and a blood processing bag set, comprising, in combination: a first pocket having an unenclosed top portion, the first pocket dimensioned to receive a blood processing bag; means to support the blood processing bag in the first pocket, the support means located adjacent the unenclosed top portion of the first pocket; a movable bottom portion below the first pocket, the movable bottom portion having an open position and a closed position; a hinged portion located along a long axis of the first pocket, the hinged portion opening to allow access to the first pocket when the movable bottom portion is in the open position; and a second pocket, wherein access to the second pocket is only possible when the movable bottom portion is in the open position.
[0044] Viewed from a third vantage point, it is an object of the present invention to provide a method for separating components from whole blood, the steps including: preparing a blood processing bag set having a processing bag, at least one auxiliary bag, a sampling site adjacent the processing bag, and a sampling site adjacent each auxiliary bag; introducing whole blood into the processing bag; sampling the whole blood for later analysis; centrifuging the whole blood, wherein components are separated in the processing bag; directing each component into the at least one auxiliary bag of the blood processing bag set; removing a sample of each component for later analysis; and storing each component for later use.
[0045] Viewed from a fourth vantage point, it is an object of the present invention to provide a bag set, comprising, in combination: a first bag having an inlet and an outlet; plural auxiliary bags, each auxiliary bag having at least one port for admitting or expelling contents of the auxiliary bags; conduit means leading from the first bag to each auxiliary bag; valve means on the conduit means, the valve means adjustable to allow selective access between the first bag and the plural auxiliary bags.
[0046] These and other objects will be made manifest when considering the following detailed specification when taken in conjunction with the appended drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] FIG. 1 shows the bag set holder of the present invention in open position.
[0048] FIG. 2 shows the bag set holder of the present invention in closed position
[0049] FIG. 3 shows the bag set of the present invention.
[0050] FIG. 4 shows the bag set in position in the bag holder in open position.
[0051] FIG. 5 shows the bag set in position in the bag holder in closed position.
[0052] FIG. 6 shows positioning of two bag holders in a conventional centrifuge.
[0053] FIG. 7 shows the bag set in the bag set holder before component separation.
[0054] FIGS. 8A , 8 B, 8 C show the stages of harvesting components from the processing bag.
[0055] FIG. 9 shows the bag set in the bag set holder after component separation.
[0056] FIG. 10 shows the bag set after collection of a blood sample before components are separated.
[0057] FIG. 10 a depicts the same state as FIG. 10 , but without the intermediate buffycoat bag.
[0058] FIG. 11 shows the bag set after the red blood cell component is separated.
[0059] FIG. 11 a depicts the same state as FIG. 10 , but without the intermediate buffycoat bag.
[0060] FIG. 12 is a flowchart of the preferred process.
[0061] FIG. 13 illustrates the separation of whole blood components in graphical form.
[0062] FIGS. 14A , 14 B, 14 C show the operating positions of the metering valve.
[0063] FIG. 15 shows an alternative embodiment of the bag set.
[0064] FIG. 16 shows the attachment of a collection bag to the bag set.
[0065] FIG. 17 shows the operation of draining the contents of the collection bag into the processing bag of the bag set.
[0066] FIG. 18 shows the disconnection of the connection bag and clot filter from the bag set.
[0067] FIG. 19 depicts the process of filling the sampling pillow with blood from the processing bag.
[0068] FIG. 20 shows the disconnection of the sampling pillow and its associated sampling port from the bag set.
[0069] FIG. 21 depicts the addition of an optional sedimenting agent to the processing bag.
[0070] FIG. 22 illustrates the insertion of the bag set into the bag set holder.
[0071] FIG. 23 is a depiction of the transfer of blood components that occurs under centrifuge while the bag set is in the bag set holder.
[0072] FIG. 24 shows the disconnection of the red blood cell bag from the bag set.
[0073] FIG. 25 illustrates the manner in which the contents of the freezing bag are mixed.
[0074] FIG. 26 depicts the process of filling the sampling pigtail with the contents of the freezing bag.
[0075] FIG. 27 shows the disconnection of the sampling pigtail and its associated sampling port from the bag set.
[0076] FIG. 28 depicts the addition of DMSO into the freezer bag and its subsequent mixing.
[0077] FIG. 29 illustrates the manner in which residual DMSO and air is drawn out of the system.
[0078] FIG. 30 shows the disconnection of the freezing bag from the bag set.
[0079] FIG. 31 illustrates the manner in which samples from the freezing bag portion are created for preservation.
[0080] FIG. 32 shows the extraction of processing bag material and the small amount of freezing bag material left in the tubing from FIG. 31 for subsequent analysis.
[0081] FIG. 33 shows the disconnection of the DMSO inlet line and its associated junctions from the processing bag.
[0082] FIG. 34 illustrates the manner in which samples are taken from the processing bag for subsequent analysis.
[0083] FIG. 35 is a schematic of the servo motor and valve system connections.
[0084] FIG. 36 plots, as a function of time while centrifuging: mass and liquid levels monitored by sensors. Also shown is the series of on/off valve rotations causing incremental weight increases of the harvested WBC solution, resulting in a full WBC freezing bag.
[0085] FIG. 37 is a further iteration of a bag set schematically showing freezer bag (white blood cell) weighing during centrifugation.
[0086] FIG. 38 reflects an alternate processing device 50 .
[0087] FIG. 39 is another view of FIG. 38 .
DESCRIPTION OF PREFERRED EMBODIMENTS
[0088] Considering the drawings, wherein like reference numerals denote like parts throughout the various drawing figures, reference numeral 10 as shown in FIG. 3 is directed to the bag set according to the present invention.
[0089] In its essence, the bag set 10 includes a whole blood processing bag 2 , a red blood cell (RBC) bag 4 having a hanger 16 , and a freezing bag 6 for the collection and storage of white blood cells. The processing bag 2 is supplied through an inlet line 12 , either through a phlebotomy needle 8 ( FIG. 10 ) or by being spiked, or sterile docked, to another bag containing the anti-coagulated blood. The processing bag 2 has an asymmetric shape including a top edge 11 a , a short side edge 11 b , a long side edge 11 c , and a sloped bottom edge 11 d between the side edges such that the bottom portion tapers to an asymmetric point 14 , which leads to an outlet 26 .
[0090] Asymmetric processing bag allows concention of a monuclear cell fraction of a white cell population in a time frame that excludes 30-50% of the granulocyte white cells. Granulocytes have no role in the hematoprietic reconstition and, thus their deletion results in a more purified selection of white cells for transplant.
[0091] Also, the asymmetric bag set allows this purification to take place without the need for a sedimenting agent—which is too viscous to sterilize through a filter—thus allowing the MNC to be concentrated in a “closed” sterile bag set as the DMSO can be made sterile by passage through a 0.2μ filter at the cryoprotectant inlet to the bag set.
[0092] The outlet 26 directs output from the processing bag 2 into a three-way metering valve 20 . The operating positions of the metering valve 20 are shown in FIGS. 14A-14C . Two supply lines 24 a , 24 b lead from the metering valve 20 to the RBC bag 4 and the freezing bag 6 , respectively. The supply lines 24 a , 24 b and the inlet line 12 may each be heat sealed and separated from the bag set 10 . All lines are equipped with line clamps 22 that may be closed to prevent fluid passage when desired. If other components are to be separated, the bag set 10 may include additional bags with a corresponding adjustment to the metering valve 20 to accommodate the additional bags.
[0093] Various supply lines may also be present in the bag set 10 . For example, the freezing bag supply line 24 b may have an inlet 16 for the introduction of cryoprotectant into the system. Such inlets may be equipped with filters 30 (see, e.g., FIG. 10 ), preferably 0.2μ filters, to, inter alia, prevent contamination from pathogens in the outside air and to allow venting of air from the freezing bag and tubing. An intermediate buffycoat bag 40 ( FIG. 10 ) may be present on the freezing bag supply line 24 b . The buffycoat bag 40 collects a separate white cell fraction, which includes platelets and white cells and includes some small volume of plasma or red blood cells. FIGS. 10 a and 11 a show the bag set without the intermediate buffycoat bag 40 .
[0094] Initially, the processing bag 2 is either filled with an anticoagulant, such as CPD (citrate, phosphate, and dextrose) and blood is drawn through a phlebotomy needle into the bag, or the inlet line is spiked or sterile docked to another bag containing anticoagulated blood. The metering valve 20 begins in the closed position ( FIG. 8A ). All clamps 22 are closed with the exception of the clamp 22 on the inlet line 12 . Blood, preferably peripheral, placental umbilical cord blood, or bone marrow is obtained from a source through the phlebotomy needle 8 or other appropriate inlet, which feeds into the processing bag 2 through the inlet line 12 . The inlet line 12 is then clamped, heat sealed, and separated from the bag set 10 . Optionally, HES may be introduced into the RBC bag 4 through an optional inlet either before or after blood collection.
[0095] At this point, the bag set 10 is placed in a bag holder 50 , shown in FIGS. 1 , 2 . The bag holder 50 is somewhat cylindrical, having a substantially elliptical shape, having two rounded ends connected by substantially straight sides. The main compartment 70 has an elongated oval shape dimensioned to receive the processing bag 2 . The main compartment 70 is accessed by sliding down a bottom portion 162 of the bag holder 50 (along arrow Z), then opening a cover 72 about a hinge 71 (along arrow X) present at one of the rounded ends of the bag holder 50 . The processing bag 2 is oriented in the bag holder 50 such that the hinged cover 72 closes over the edge 11 c coinciding with the point 14 leading to the metering valve 20 . The metering valve 20 is received in an orifice 74 a located on the major portion of the bag holder 50 . A complimental orifice 74 b , located on the hinged cover 72 , receives the protruding end of the metering valve 20 . The hinged cover 72 will only close when the bottom portion 162 is in the closed position. When the bottom portion is closed, a notch 164 in the bottom portion 162 registers with a retaining tab 166 present on the main body of the bag holder 50 .
[0096] Referring to FIG. 1 , the bag holder 50 includes a bag hanger 76 having hooks 60 that engage the loops 28 on the processing bag 2 , maintaining the bag in position during the centrifuging process. The main compartment 70 of the bag holder 50 is shaped to receive the processing bag 2 , having a sidewall 156 that is complemental to the asymmetric shape of the processing bag 2 , which terminates in an outport 160 dimensioned to receive the asymmetric point 14 and the outlet 26 of the processing bag 2 . The sidewalls 156 cradle the processing bag 2 loosely around the middle and more tightly at the bottom (near the outlet 26 ). Closer tolerance near the bottom of bag 2 is desired to minimize disturbing the contents of the bag after sedimentation. Thus, the top of compartment 70 mirrors the exterior elliptical shape but tapers down to the outport 160 while maintaining bag edges 11 b , 11 c , 11 d in supporting relationship.
[0097] A notch 78 is present along one of the substantially straight sides of the bag holder 50 . The notch 78 receives the hanger 16 on the RBC bag 4 . The RBC bag 4 hangs along the outside of the bag holder 50 in a curved recess 80 leading to a lower support shelf 83 via transition 81 . The freezing bag 6 is cradled in a receptacle 82 located beneath the main compartment 70 of the bag holder 50 , accessed by sliding the bottom portion 162 down to open along arrow Z. FIGS. 4 and 5 show the entire bag set 10 loaded in the bag set holder 50 before component separation occurs. FIG. 37 shows a further iteration of a bag set showing schematically that the freezer bag is weighed during the separation process. FIG. 38 shows the freezer bag has been encapsulated in a shell 501 which depends from platform 503 that supports, on its top side a control chip module 57 and on its bottom side the shell and freezer bag via a weighing load cell 505 . Shell 501 floats in an air space 508 , protected by “U” shaped bracket 509 .
[0098] The metering valve 20 is connected to a motor driver 56 in the bag holder 50 . The servo motor 56 is connected to a software-controlled control chip module 57 powered by a rechargeable battery B. Module 57 may require temperature compensation due to heat generation during centrifugation. A port P is provided to utilize a battery charger C ( FIG. 35 ). The servo motor 56 controls the operation of the metering valve 20 while the bag set 10 is mounted in the bag holder 50 . One or more optical sensors 58 trigger the proper time for the servo motor 56 to close the metering valve 20 after each fraction is harvested. The sensor may be present at the position shown in FIG. 1 or lower, closer to the outport 160 ( FIG. 8C ) adjacent the asymmetric point 14 of the processing bag 2 . Sensors 58 , for example may monitor all branches around valve 20 and the inlets of bags 4 and 6 . The sensor 58 shown is optical but can be based on density, weight, infrared, radioactivity, fluorescence, color, magnetism, ultrasonics, capacitance, wherein the characteristic measured may be an additive.
[0099] The bag holder 50 , when closed, is adapted to fit into a centrifuge cup 66 dimensioned to reside within a conventional centrifuge 100 . Preferably, at least two bag set holders 50 are placed in diametrically opposed centrifuge cups 66 , as shown in FIG. 6 , for balance. A bag set 10 in the centrifuge cup 66 may be subjected to more than one G-force in order to achieve the optimum stratification of components ( FIGS. 8A-8C ). The servo motor 56 then operates the metering valve 20 to open and allow access to supply line 24 a for the harvest of red blood cells, at an optimum G-force, into bag 4 . The servo motor 56 closes the metering valve 20 when the optical sensor 58 indicates that the red blood cells are harvested (FIGS. 8 A, 8 B). The optical sensor 58 senses the boundary between the white cell fraction and the plasma fraction.
[0100] The next fraction, which includes white cells and/or platelets, is then harvested from the processing bag 2 ; the servo motor 56 opens the metering valve 20 to allow access to supply line 24 b ( FIG. 8C ) leading to bag 6 for the next harvest. As shown in FIG. 9 , during the harvest (WBC) into the freezing bag 6 , air in the supply line adds to air already in the freezing bag 6 , producing an air bubble 70 , which is useful to assist the proper mixing of the WBC and/or platelets with the cryoprotectant. The servo motor 56 then closes the metering valve 20 , as shown in FIG. 8A , and the centrifuge 100 is allowed to stop. FIG. 9 shows the bag set 10 in the bag set holder 50 after component separation has taken place.
[0101] The buffycoat bag 40 , if present, preferably has a 25 ml capacity. 20 ml of buffycoat is introduced into the buffycoat bag 40 , and 5 ml of DMSO solution is subsequently introduced. The buffycoat bag is placed between two cold strata and rotating or kneading of the buffycoat bag 40 in order to mix the cryoprotectant and WBC solution takes place.
[0102] The bag holder 50 is removed from the centrifuge cup 66 and opened, and the bag set 10 is removed, with the servo motor 56 disconnected from the metering valve 20 . Each supply line 24 a , 24 b is clamped, heat sealed, and removed from the processing bag 2 . Any additional bags may be similarly removed.
[0103] After the supply line 24 b connected to the freezing bag 6 is disconnected, a cryoprotectant may be introduced into the collected component in the freezing bag 6 through an inlet. The air bubble 70 in the freezing bag 6 allows the cryoprotectant to be thoroughly mixed with the collected component. After mixing, the air bubble 70 is expelled, perhaps through a filter-protected cryoprotectant inlet 16 ( FIG. 10 ). The component is then prepared for storage by heat-sealing the tubing and removing the bag 6 downstream of the cryoprotectant inlet 16 .
[0104] Preferably, each line (the inlet line 12 and the supply lines 24 a , 24 b ) is oriented to allow access to a sampling site (e.g., site 18 ) near the collection or storage bags. Thus, a sample of the blood or fluid in the line may be taken without disturbing the bulk of the collected component.
[0105] FIG. 13 depicts the separation of whole blood components as a function of time. Under centrifugation, each fraction stratifies in the processing bag 2 as a function of its density. The overlapping areas 175 ( FIG. 13 ) indicate the area in the separation along each strata line in the processing bag 2 . As centrifugation continues, the boundary of each fraction becomes more clearly defined; thus, the area 175 ( FIG. 13 ) decreases and each fraction is more completely harvested. Thus, the centrifugation strategy combines separation by density, the time involved for stratification, which differs with the exterior surface area and density of the various cells, centrifugal force, and boundary layer clarity. Decisions on harvesting will vary based on these tradeoffs as a function of the constituent of greatest value and its desired purity.
[0106] Preferably, the stratification centrifugation occurs at an excess of 1000 Gs, preferably 1400 Gs, for approximately 20 minutes. The transfer centrifugation step occurs at less than 100 Gs, preferably 78 Gs, and stops subject to output from the optical sensor 58 . The right hand side of FIG. 36 shows the white cell bag (Freezer bag 6 ) topped off in increments by throttling the valve 20 on and off in order to extract the WBC population.
[0107] It is appreciated that while the instant invention is preferably used in the separation of blood components, the separation techniques and apparatus are suitable for separation of other fluids. The software programmed into the control chip module may cause the servo motor to open and close the valve many times, thereby throttling the valve during strata delivery. Also by varying time increments during a harvest procedure, precise cut-offs between the cell components can be achieved in order to reduce the mixing between cell types that may occur as a result of the “toroidal” (Coriolis) effect during removal of the blood component from processing bag 2 and may be modified for the separation of other fluids or to compensate for various hardware conditions, such as uneven centrifuge loading.
[0108] Yet another embodiment of the bag set 210 is shown in FIG. 15 . In its essence, the bag set 210 includes a whole blood processing bag 202 , a red blood cell (RBC) bag 204 , and a freezing bag 206 . The processing bag 202 is supplied through an inlet line 212 that terminates in a spike 208 . The processing bag 202 has an asymmetric shape including a top edge 211 a , a short side edge 211 b , a long side edge 211 c , and a sloped bottom edge 211 d between the side edges such that the bottom portion tapers to an asymmetric point 214 , which leads to an outlet 226 . The outlet 226 directs output from the processing bag 202 into a stopcock valve 220 . Two supply lines 224 a , 224 b lead from the stopcock valve 220 to the RBC bag 204 and the freezing bag 206 , respectively. The supply lines 224 a , 224 b and the inlet line 212 may each be heat sealed and separated from the bag set 210 . All lines are equipped with line clamps 222 that may be closed to prevent fluid passage when desired. If other components are to be separated, the bag set 210 may include additional bags with a corresponding adjustment to the stopcock valve 220 to accommodate the additional bags.
[0109] Initially, the blood of interest is collected in a collection bag 200 or similar container. The spike 208 is inserted into the collection bag 200 , and the blood is drained from the collection bag 200 into the processing bag 202 through the inlet line 212 (FIGS. 16 , 17 ). The inlet line 212 preferably has a clot filter 230 , through which the blood passes before it reaches the processing bag 202 . After the blood is transferred, the inlet line 212 is heat sealed and the collection bag 200 and clot filter 230 are removed ( FIG. 18 ).
[0110] The inlet line 212 also preferably has a sampling port 232 , a sampling pillow 234 , and an access port 236 ( FIG. 19 ). After the collection bag 200 and clot filter 230 are moved from the inlet line 212 , the sampling pillow 234 is squeezed and released to fill the sampling pillow with blood. The inlet line 212 is then heat sealed and the sampling pillow 234 is removed, along with the sampling port 232 ( FIG. 20 ). The blood in the sampling pillow 234 may then be accessed through the sampling port 232 for separate assay.
[0111] Unlike the prior art where a sedimentation agent is required, a sedimenting agent, such as hydroxyethyl starch (HES) may optionally be added to the processing bag 202 through the access port 236 on the inlet line 212 using syringe means 236 a or similar delivery means, and the processing bag 202 is manipulated to thoroughly mix the agent with the blood ( FIG. 21 ). The bag set 210 is then placed into the bag holder 50 and used with a centrifuge, as detailed hereinabove, to separate the cells therewithin ( FIG. 22 ). The separated red blood cells are transferred into the RBC bag 204 and the WBC fraction is transferred to the freezing bag 206 during this operation. The bag set 210 is then removed from the bag holder 50 ( FIG. 23 ). Supply line 224 a is then heat sealed and the RBC bag 204 is removed ( FIG. 24 ). The contents of the RBC bag are accessed through a sample port 238 .
[0112] Referring to FIG. 25 , supply line 224 b is preferentially equipped with a first junction 260 connecting an auxiliary inlet line 240 terminating in an auxiliary port 242 . A second junction 262 is present on the auxiliary inlet line 240 itself to connect a branch line 244 that terminates in a bulb 246 . The branch line 244 also contains a sampling pigtail 248 and a sampling port 250 . After removal of the RBC bag 204 , the bulb 246 on the branch line 244 is squeezed to direct any residual plasma remaining in the supply line 224 b into the freezing bag 206 . Clamp 222 on branch line 244 is then closed. The contents of the freezing bag 206 are then mixed, preferably by holding the freezing bag 206 at a 45° angle and slowly squeezing the small compartment 206 a of the freezer bag 206 a total of ten times at one squeeze per second.
[0113] The clamp 222 on the branch line 244 is then opened, and the bulb 246 is squeezed and released to fill the sampling pigtail 248 with the contents of the freezer bag 206 ( FIG. 26 ). The branch line 244 is heat sealed and removed from the bag set 210 ( FIG. 27 ). The contents of the sampling pigtail 248 are accessed through the sampling port 250 for separate assay.
[0114] The freezing bag 206 is placed on its side and sandwiched between two ice packs 252 ( FIG. 28 ). DMSO is introduced into the freezing bag 206 through the auxiliary port 242 which has a sterile filter 242 a (i.e. less than or equal to 0.2 microns) on the auxiliary inlet line 240 . An orbital mixer 254 is used with the sandwiched freezer bag 206 to thoroughly mix the contents of the freezer bag 206 . The sandwiched freezer bag 206 is then placed in stationary holder 256 ( FIG. 29 ). A syringe 258 is inserted into the auxiliary inlet 242 and used to draw out any residual DMSO and trapped air in the supply line 224 b and the auxiliary inlet line 240 . The buffy coat/DMSO from the freezing bag 206 is drawn out by the syringe 258 until it reaches the second junction 262 from the supply line 224 b . The freezing bag 206 is then removed from the bag set 210 by heat sealing the supply line 224 b ( FIG. 30 ).
[0115] A portion of the supply line 224 b after the first junction 260 remains attached to the freezing bag 206 . This portion of the supply line 224 b is heat sealed to form three separate samples 275 a , 275 b , 275 c (still connected to the freezing bag 206 ), and the area separating the small compartment 206 a of the freezer bag 206 is heat sealed to separate it from the rest of the freezer bag 206 ( FIG. 31 ). The final product is then frozen for storage.
[0116] The stopcock valve 220 is turned to allow plasma in the processing bag 202 to contact the buffy coat in the supply line 224 b near the first and second junctions 260 , 262 ( FIG. 32 ). A sample of the plasma diluted buffy coat is drawn into the syringe 258 for bacterial sampling, and the syringe 258 is removed from the auxiliary port 242 . The supply line 224 b containing the auxiliary line 240 and the first and second junctions 260 , 262 is then disconnected from the processing bag 202 and is discarded ( FIG. 33 ). Samples of the plasma in the processing bag 202 may be removed by using the access port 236 ( FIG. 34 ).
[0117] Moreover, having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the instant invention as set forth hereinabove and as described hereinbelow by the claims.
|
An apparatus and method for collecting whole blood and then separating it into components for subsequent use or storage. A self-contained bag set is used to collect the sample, which may then be placed into a device adapted to fit into a centrifuge for separation of components. Each component is then sequentially extracted according to density, with a sensor present in the device to control the operation of valves directing the collection of each component. The sensor may be reading one or more of the following characteristics: infrared, optics, density, weight, radioactive, fluorescence, color, magnetism, ultrasonic, capacitance wherein the characteristic is inherent in the blood and blood component or is an additive. Each component may then be separated into its own storage container. The preferred sensors include optics and weight. Besides blood density separation, the device may contain a solution including cells, proteins, subcellular particles or viruses which may be mixed with affinity media or antibodies prior to separation.
| 0
|
This application claims the benefit of U.S. provisional patent application No. 61/539,036 filed Sep. 26, 2011.
BACKGROUND OF THE INVENTION
The angular disposition of a sound source from a position directly in front of a listener to a position to the side of a listener is accompanied by audible amplitude increases in frequencies greater than ˜300 Hz at the near side (outer ear contributions), reduced amplitudes at the far side (because of the head shadow), and relative phase differences and arrival times to each ear. Such cues are used by the brain to locate angular or azimuth sound source positions relative to the listener. Additional cues created by outer ear geometry allow vertical sounds to be located.
Stereophonic playback inherently creates such cues for two loudspeaker locations as the sound sources that are correspondingly processed by the listener's brain. These cues psychoacoustically define an essentially flat two-dimensional soundstage that spans the area between the speakers.
The present invention relates to a new method and apparatus for accurately interfacing three-dimensional spatial cues inherently embedded in audio sources with a listener's cognitive psychoacoustic responses when the sources are played back through two loudspeakers.
BRIEF DESCRIPTION OF THE PRIOR ART
Numerous attempts have been made to diminish spatial playback shortcomings. Typical examples are signal processors that subjectively widen the apparent image of the reproduced sound stage using phase shifts and/or equalization as disclosed for example in the Bruney U.S. Pat. Nos. 4,495,637 and 4,567,607 and Kirkeby U.S. Pat. No. 6,928,168. Also known are designs which apply equalization, phase shift, or time delays as disclosed in the Carver U.S. Pat. No. 4,218,585, the Myers U.S. Pat. No. 4,817,149, and the Suzuki U.S. Pat. No. 7,711,127 or processes that create “surround-sound” effects using multiple loudspeakers or phase-shifting effects. Other examples include multiple-speaker recording and/or playback techniques as disclosed for example in the Lokki et al U.S. Pat. No. 7,787,638. Attempts have been made to address various problems that arise from multi-speaker geometries, such as phase shifts to avoid intracranial sense as disclosed in the Kasai et al U.S. Pat. No. 7,242,782. All of these prior efforts create various forms of image distortions. These designs fail to recognize that dimensional cues are inherently preserved in audio feeds as a function of the location of a sound source relative to a microphone, fail to take into account the consequences of attempting to reproduce the spatial location of a real single sound source with two loudspeakers resulting from a misapplication of existing head related transfer functions, and fail to understand human cognition responses, i.e., how sound is interpreted by the mind.
The first successful attempt at dimensionally accurate image fidelity was described in the Bruney U.S. Pat. No. 4,204,092 which incorporated an additional factor crucial to spatial localization. Here, the role of the well-known Fletcher-Munson (F-M) effect to both distance and angular perception via the shape of the outer ears and head was first hypothesized. The passive circuit interface described in the patent incorporated four loudspeakers in a coordinate system centered on a listener. It presented sounds to the listener's ears that tracked relative channel balance analogous to the outer ear and head shadow effects that occur in natural free-field hearing. This allowed inherently encoded angle and distance information between sound sources and microphones to be accurately perceived in the forward 180° free-field environment of a listener, with the listener virtually occupying the position of the recording microphones. However, the Bruney '092 patent did not appreciate that relative phase differences between the ears arose intrinsically for the side-positioned speakers in the configuration. Nor were the phase differences anticipated or the explicit frequency changes addressed in the two-speaker versions described in the same patent.
The only other notable three dimension design is a recent one that is optimized for the playback of binaural recordings; i.e., recordings made with a binaural mannequin head. Such recordings already contain outer ear and head shadow modifications and are traditionally intended for headphone playback. This two-speaker playback process utilizes an elaborate set of filters to cancel the inherent acoustic location cues of the two loudspeaker positions and operates at frequencies primarily below 6 kHz. It requires a calibration procedure that measures the acoustical traits of the playback environment in conjunction with the listener's outer ears and head shadow or, less optimally, a binaural mannequin head in the listening position. Listener location (the so-called “sweet spot”) is critical, as the system requires minimizing the head shadow effect. The loudspeakers are optimally placed closely together with the subtended angle between the speakers and the listener about 10°. Greater speaker separation reduces image quality. It is best suited to physically small loudspeakers to minimize image shifts caused by small head movements. Playback of mixed-microphone recordings using this method does not address the consequences of reproduced sound sources located at different angles relative to a listener and does not attempt to provide additional head and outer ear modifications.
SUMMARY OF THE INVENTION
The present invention is based on a greater understanding of how humans hear. It represents a comprehensive application of cognitive neuroscience that spans both recording and playback processes by directly addressing how sound is interpreted by the brain. The resultant interface establishes a direct link between stimuli or location cues in sound sources and the corresponding cognitive hearing responses.
It is a primary object of the present invention, using only two speakers, to allow a listener to accurately perceive distance information inherently encoded within standard audio recordings as a function of the distance between recorded sound sources and the recording microphones, or the distance information as modified by recording and/or mixing techniques. Another object of the invention is to accurately recover and reproduce angular information within recordings as a function of stereo channel balance by using newly derived hearing measurements made with two correlated sound sources. These hearing measurements produce curves referred to as stereo transfer functions or STFs. Additional consequences are the ability to discern vertical image locations preserved in standard recordings, a broadened listening position including not only the optimal position but also regions to either side where spatial cues can be perceived, and significantly improved sonic clarity and detail presently conjectured as related to the precision of reproduced locations. These objects are accomplished without highly-restrictive limitations on loudspeaker size, type, or location by directly linking dimensional cues embedded in audio program sources to the psychoacoustic responses of a human listener via a precision audio cognition interface. Interface applications include, but are not limited to, music reproduction, movie soundtracks, television sound, 3-D movies, 3-D video games, and 3-D television, wherein apparent moving sound sources in three-dimensional space are faithfully synchronized with and track their corresponding three-dimensional moving visual images.
A primary problem addressed by the invention concerns the non-linear nature of human cognitive hearing responses as it pertains to stereo image fidelity. The focus of this nonlinearity is the above-mentioned Fletcher-Munson effect. This “loudness” trait demonstrates that the perception of sounds does not strictly correspond to reality. The Fletcher-Munson measurements show that the same tonal balance is perceived differently at different volume levels, and over the changing volume range there is little or no linear correspondence of what is subjectively heard relative to the frequency balance actually present. The more sophisticated ability to discern sound locations in three-dimensional space directly involves the Fletcher-Munson effect, so the listener's ability to localize sounds reproduced through two stereo loudspeakers is likewise subject to associated nonlinearities with unanticipated consequences.
For this reason, the playback method and apparatus of the present invention employ a new approach: unique equalization and phase curves derived from new free-field hearing measurements. The measurement method was developed solely for the purpose of faithful angular (azimuth) image reproduction relative to a listener using two loudspeakers.
The resulting curves represent a notable departure from the prior art. There have been numerous attempts in stereo playback to make spatial imaging more natural. Some past efforts incorporate conventional measurements of sound locations relative to the human head. These measurements are derived using a single sound source of fixed volume level placed in various equidistant positions around a human subject. The measurements denote the location of the real sound source and yield well-known head-related transfer functions or HRTFs. However, employing HRTF curves in stereo playback fails by varying degrees to accurately restore apparent image locations. The difference is that the locations are played back by one or both off-center sound sources (the two loudspeakers) placed in fixed positions forward of the listener's head rather than a real single sound source positioned at some angle relative to the listener's head. One would naively expect that these speaker-related location changes relative to the listener could be correspondingly corrected using the existing HRTF curves. However, the perceived location changes are additionally aberrated by the nonlinear Fletcher-Munson process involved in sound localization. This thwarts the ability to straightforwardly calculate the HRTFs for the stereo format and instead results in unanticipated and largely unpredictable differences in the perception of reproduced sound locations.
By contrast, the azimuth curves of the subject invention avoid the HRTF failings altogether by directly measuring what two stereo loudspeakers must do to accurately reproduce the apparent sound positions. These new and distinctly different curves are the aforementioned stereo transfer functions (STFs). They are derived from measurements of two stationary real sound sources and denote various locations of a single imaginary or virtual sound source as determined by the listener. These curves uniquely redefine outer ear/head shadow corrections for two-speaker playback and reveal critical areas of error when misapplying standard HRTF curves.
In the present invention, these STF curves are applied such that relative channel balance in normal stereo sound sources is equated to the forward 180° free-field space centered on the listener. A second test method, analogous to the first, employs these unique curves to provide accurate distance perception using two loudspeakers.
Consequently, the new STF parameters are combined with the knowledge of the link between spatial localization and the Fletcher-Munson, or loudness, effect and can be incorporated within active circuitry or software for stereo playback applications. The resulting audio process utilizes only two speakers and allows the listener to accurately localize distance, angular, and vertical image locations inherently preserved in standard recordings. Adjustments for equalization and phase accommodate a range of different speaker/listener geometries, loudspeaker types, and variations in recordings.
Although primarily intended for imaging in the forward 180° free field of a listener using regular, mixed multi-microphone recordings, some sound locations recorded slightly behind the listener can be accurately reproduced. Further, an optional modified method and apparatus is designed to accommodate non-standard recordings made either with a binaural head or with a pair of closely spaced microphones. The success of this option depends heavily on the performance of filters used in the phase-related portions of the apparatus execution.
BRIEF DESCRIPTION OF THE FIGURES
Other objects and advantages of the invention will become apparent from a study of the following specification when viewed in the light of the accompanying drawing, in which
FIG. 1 is a circuit diagram of the testing format of the free-field two-speaker azimuth according to the invention;
FIG. 2A is a graphical representation of the resultant azimuth equalization and phase plots (STF curves) from the tests of FIG. 1 and typical HRTF curves for the same 90° image location;
FIG. 2B is a graphical representation of an HRTF curve for a ±180° range of single sound source locations at 2.2 kHz;
FIG. 3 is a diagram illustrating a Fletcher-Munson/localization demonstration test;
FIG. 4A is a block diagram illustrating the interrelationships among the three essential elements and an optional fourth element of the auditory cognition method of the present invention;
FIG. 4B is a schematic block diagram of the apparatus of the present invention;
FIG. 5A is a graphical representation of the mixed bridge attenuation function for individual stereo channels relative to channel balance according to the invention;
FIG. 5B is a graphical representation of the mixed bridge cross-feed function for a single channel input;
FIG. 5C is a schematic diagram of a mixed bridge resistive network; and
FIG. 6 illustrates graphical plots for ranges of equalization and filter/phase cross-feed settings.
DETAILED DESCRIPTION
In FIG. 1 , there is shown a layout of the new free-field test system utilized to determine listener responses to stereo playback in accordance with the inventive method. In these tests, a range of audio signals are played back through a pair of stereo speakers configured in traditional stereo geometry wherein the listener and the speakers form an equilateral triangle. In the tests, a group of subjects is asked to compare the stereo signals directly to corresponding sounds from a single reference loudspeaker located either directly in front of the listener at 0° or to one side at 90°, such that the location of the sound from the reference speaker and the apparent location of the sound from the stereo speaker or speakers is indistinguishable. All of the subject's results are averaged for the final set of curves. The resultant stereo curves or stereo transfer functions (STFs)—which are in the form of azimuth equalization curves—recreate sound image angles equivalent to those of a single real loudspeaker located either directly in front of a listener at 0° or to one side at 90°.
More particularly, FIG. 1 shows a layout of the free-field tests conducted outdoors in an open field, wherein the 0° and 90° reference speakers are shown, respectively, in front of and to the right of the subject. All amplifiers in the test are identical with equal gains. All speakers in the test are identical and positioned at ear height.
The test apparatus includes a sine wave generator 1 and pink noise generator 2 as the signal sources with a bandpass filter 3 in series with the pink noise generator. The signal generator and center of the bandpass filter are always tuned to the same frequency. The pure tone and filtered noise are mixed together or selected separately at a mixer 4 . The mixer output is delivered to a stereo/reference selector switch 5 . From switch 5 , the signal is switched either to reference selector switch 6 or to the rest of the stereo speaker input circuits. The reference selector switch 6 selects between the side reference speaker 7 or the center reference speaker 8 via power amplifier 19 . The distances 17 between the reference speakers and the listening subject 9 are equal.
If the selector switch 5 is in the stereo pair position, the signal passes to phase switch 10 which selects between a phase inverter 11 or a bypass line 18 . Both go to the left channel volume control 12 . The signal also goes directly into the right channel volume control 13 . Both signals then pass through the dual overall volume control 14 . The respective output signals then pass through respective left and right amplifiers 20 and 21 and to left and right speakers 15 and 16 , respectively. Signal amplitudes are measured at reference speaker test point 22 and respective left and right speaker test points 23 and 24 .
Test subjects make adjustments so that the individual sounds reproduced by the stereo speaker pair were indistinguishable in loudness and angle from the reference source when switched. The subjects compare the reproduced sound source directly with the real reference sound source by using the selector switch, 5 . Multiple tests were conducted at test frequencies ranging from 20 Hz-15 kHz. For some frequency bands, both a pure tone and bandwidth-limited noise (using a narrow bandpass filter centered on the same frequency) needed to be mixed together as an aid to localization. Only the pure tone amplitudes were then compared and measured.
The following is a summary of the test method steps:
(A) Select frequency (B) Select front or side reference speaker
(1) Listen to the reference speaker
(2) Listen to speaker pair for level and angular location
(3) Adjust speaker pair levels
(4) Compare apparent level and angular location to reference speaker
(5) Repeat steps 1-4 until no difference is heard in level and angular location
(6) Record speaker pair levels for that frequency
(C) Select next frequency (D) Repeat steps 1-6 (E) Repeat all steps for other reference speaker positions.
In FIG. 2A , the averaged curves for both channels are shown. The dashed plot 25 represents a centrally placed monaural signal from speaker 8 , plot 26 A represents the near signal from speaker 16 , and plot 27 A represents the far signal from speaker 15 . The signals corresponding to the latter plots 26 A and 27 A, when heard together, are the psychoacoustic equivalent of the 90° side-positioned sound source of speaker 7 . Plots 26 A and 27 A together constitute the stereo transfer functions for 90°. The frequencies between 200 Hz-1.5 kHz that are reproduced by speaker 15 represented by plot 27 A are fixed at 180° out-of-phase with the corresponding frequencies reproduced by speaker 16 represented by plot 26 A. The out-of-phase condition was chosen for its simplicity and ease of incorporation into the tests.
For reproducing the monaural tones only, which correspond to the position of speaker 8 at 0°, the frequency response of left and right stereo channels remains flat, but their individual levels are reduced by −3 dB each. The result is that the two loudspeakers 15 and 16 sum their outputs acoustically by +3 dB. This −3 dB level is shown as the 0 dB reference level in the curves of FIG. 2A with the left and right channel levels actually expressed relative to 0 dB. Note that this same total −3 dB monaural reduction is incorporated within studio stereo recordings where Orban-type pan potentiometers are used for placing signals relative to left or right channels (i.e., −3 dB in both channels for centrally-located sounds).
Relative amplitudes for intermediate angles are not shown, but can be derived by the same measurement process.
Plot 26 A in FIG. 2A can be characterized as possessing specific regions: a flat response for all frequencies <100 Hz; a transition region in the 100-200 Hz range; another essentially flat response between 200-500 Hz; a very slight transition downward between 500-800 Hz; another upward transition between 800 Hz-1 kHz; an increasing slope from 1 kHz to ˜2.3 kHz; a downward transition from ˜2.3 kHz to a minimum at 4 kHz; and a generally increasing range above 4 kHz with peaks at ˜6 kHz, a maximum at ˜10 kHz, a lower peak at ˜15 kHz, and intervening dips at ˜8 kHz and ˜12 kHz.
The unexpected imaging deviations created by stereo playback are first seen by comparing the common regions of line 26 A with the corresponding HRTF curves such as disclosed in Sivian, L., et al, On Minimum Audible Sound Fields , J. Acoust. Soc. Amer., 4, 1933, p. 288-321. The HRTF curves for the near and opposite ears for a sound source located at 90° to one side of a listener are shown by respective long-dashed plots 26 B and 27 B in FIG. 2A .
In plot 26 A, the flat region between 200-500 Hz is +6 dB above the 0° (monaural) level. By contrast, the HRTF plot 26 B notably differs; at 300 Hz it is +1.5 dB and at 500 Hz it is +4 dB. At 1 kHz, plot 26A is +7.5 dB, whereas HRTF plot 26 B has a peak at 1.1 kHz of only +6 dB. At 2.2 kHz, plot 26 A has a peak at +10 dB, whereas the HRTF curve 26 B falls considerably in the opposite direction at +4 dB. At 3.2 kHz, plot 26 A is +6.5 dB, whereas HRTF plot 26 B is still very low at only +2 dB.
It should be noted that the latter two large deviations occur in the most sensitive or audible frequency range of human hearing. At 4.2 kHz, plot 26 A is +3 dB and HRTF plot 26 B is +1.5 dB. At 5 kHz, plot 26 A is +9.5 dB and HRTF plot 26 B is +7 dB. At 6.6 kHz, plot 26 A is +13 dB and the HRTF plot is +11 dB. At 7.6 kHz, plot 26 A dips down to +7.5, but the HRTF plot 26 B peaks at +16 dB. At 10 kHz, plot 26 A peaks at +16 dB, but the HRTF plot 26 B drops to +11 dB. At these two latter points, the frequencies of the troughs and strong peaks have exchanged positions between 7.6 kHz and 10 kHz. These frequencies are in the region of the spectrum associated with the perception of vertical elevation. At 12 kHz, plot 26 A and HRTF plot 26 B are both +9 dB. At 15 kHz, plot 26 A rises to about +10.5 dB, whereas HRTF plot 26 B is −3 dB.
The more pronounced comparison discrepancies cited in the frequency bands above coincide with the same frequency regions of the Fletcher-Munson curves that exhibit increased nonlinear loudness responses.
The deviations of plot 27 A from the HRTF curves are also revealing. At 300 Hz, both plot 27 A and the HRTF plot 27 B are equal at 0 dB. At 500 Hz, plot 27 A remains at 0 dB, whereas the HRTF plot 27 B drops to −3 dB. At 1 kHz, plot 27 A remains at 0 dB and the HRTF plot 27 B is −1 dB. At 1.5 kHz, plot 27 A remains at 0 dB, then drops dramatically above that. There is no HRTF value for 1.5 kHz but an interpolated value would be −2.5 dB. At 2.2 kHz, plot 27 A is −10 dB, whereas the HRTF plot is only −4.5 dB.
It was noted in measuring the STF curves that any output in plot 27 A immediately above 1.5 kHz reduces the angular location of the side image, so the steepness of the slope just above 1.5 kHz is critical.
Test subjects further reported that the out-of-phase signal, plot 27 A, was absolutely necessary throughout the 200 Hz-1.5 kHz range in order to place images 90° to the side of the listener. This STF range and phase result departs significantly from previous conventional single-sound-source hearing data, which indicates that phase sensitivity diminishes above the 700-800 Hz maximum-sensitivity range (wavelengths˜19.3″-16.8″) and becomes essentially non-existent at approximately 1.4-1.5 kHz.
It is, however, understandable that such out-of-phase information at 1.4-1.5 kHz could still be processed by the hearing localization system when stimulated by the two-speaker playback geometry in the tests. The 700-800 Hz region is associated with the width of the head. Since an average ear-to-ear distance is ˜6.5″, this suggests that the out-of phase ½-wavelength in this maximum phase-sensitivity range, or about 9.65-8.4″, corresponds to the lengths of acoustic paths around the head to the opposite ear. For example, a 1 . 5 kHz sine wave (the averaged resultant frequency of the azimuth tests) has a wavelength of 9″, which is approximately half a 750 Hz wavelength (the average frequency of maximum phase sensitivity). A sine wave at this frequency, emanating from a single 90° sound source, is attenuated by the head but not totally blocked from the far ear. As such, an out-of-phase condition can exist at opposite ears for two consecutive 1.5 kHz wavelengths. Human localization ability may thereby still naturally possess a reduced sensitivity to this frequency range when strongly excited by two distinctly separate but correlated sound sources.
It is also easily shown that the HRTFs for loudspeakers at a given location cannot be simply calculated to produce the above STF curves. For example, consider attempting to reproduce an apparent 90° sound position from a speaker located at 30°. According to the HRTF curve 27 C for 2.2 kHz ( FIG. 2B ), a speaker positioned at 30° has an amplitude contribution of +2.5 dB relative to 0 . That frequency would only need a +1.5 dB boost to be equivalent to the HRTF value of +4 dB to create an apparent 90° sound location, whereas the measured STF value for an apparent 90° location is actually +10 dB. The computed HRTF correction has an error of −6 dB. This error would place the sound only slightly beyond the actual loudspeaker location rather than out to the extreme side of the listener.
More generally, the cognitive STF shapes, frequency peaks, troughs, amplitudes, and phases in critical portions of the spectrum differ in non-obvious and significant ways from their conventional HRTF counterparts.
It should be emphasized that neither distance perception nor vertical perception was evaluated in the above azimuth tests which instead focused exclusively on relative amplitudes and angles of single tones alone, not the subjective judgments of distances or elevations of groups of frequencies taken as single signals in the near field.
In near field hearing, overall volume level decreases as a sound source moves away from a listener or a microphone. Low frequency amplitudes decrease more rapidly with increasing distance relative to midrange content because of low-frequency omnidirectional dispersion, while higher frequencies, which tend to be directional or beaming, are attenuated with increasing distance by dissipative losses in the air medium. Only low frequencies persist at great distances.
A connection exists between these acoustic properties and the evolved frequency bias of the Fletcher-Munson loudness effect, where higher volume levels appear to have more high- and low-frequency content relative to midrange frequencies than sounds at lower volume levels. Distance assessments of complex sounds and angles, such as occur in everyday hearing, intrinsically entail the relationship between the geometry of the head and ears and the Fletcher-Munson effect. The effect compliments the shape and size of the head and outer ears and is thus directly implicated in angular, vertical, and distance localization. Distance perception is in turn dependent on the degree of intracranial sense, which in its pure form, such as with headphones, creates the illusion that the sound is completely inside a listener's head. In free-field hearing, as the proportion of this sense is increased, the relative distance of a sound source is perceived as coming closer to the listener.
As a clear illustration of this interrelationship, consider the 4-speaker geometry in FIG. 3 , with all speakers placed equidistant to the listener. Left and right loudspeakers 28 and 29 , respectively, are positioned forward of the listener 30 and loudspeakers 31 and 32 are located to the listener's respective left and right sides. The speakers are driven with a single channel of a preamplifier/amplifier 33 equipped with bass and treble tone controls, 34 and 35 , respectively, and a single main output volume control 36 . The preamplifier/amplifier uses a pink noise generator 37 as its sound source.
With tone controls in the flat position without any boosts or cuts, the monaural pink noise source is fed through the preamplifier/amplifier 33 to both front speakers equally, such that the noise appears centered between the two front speakers. The same sound is fed equally to both side speakers at a reduced but still audible volume with an in-line volume control 38 . This moves the apparent center sound somewhat closer to the listener. In this format, the side speakers provide sounds analogous to those reflected down the ear canals by the outer ears during free-field hearing of an actual centrally-placed sound source. This is an active angle-dependent outer ear function that remains static during stereo (two-speaker) playback. Side-speaker volume control 38 determines a ratio that remains fixed. Any changes in the main volume or tone control settings via control 36 and controls 34 and 35 occur together by the same ratio in all speakers.
If either the bass or treble or both tone controls are turned up, the sound will be heard to advance toward the listener. If either or both are turned down, the sound will appear to recede away from the listener. If the listener repeats these steps with one ear plugged, the sound will appear to move angularly either towards or away from the side of the open ear, respectively. The change in tonal balance defines an angular clue to the listener. If, instead of manipulating the tone controls, the main output volume control 36 is either increased or decreased, the same distance and angular results will be observed because of the subjective change in tonal balance created by the listener's Fletcher-Munson effect. This also illustrates that the side speaker sounds, analogous to the reflected outer ear contributions, operate in concert with the Fletcher-Munson effect to vary the proportion of intracranial sense, and thereby distance perception, when heard with both ears. For this reason, a variable Fletcher-Munson loudness control, well-known in the art, can be used instead of tone controls as an adjustment for apparent image distances when the proper outer ear contributions are present.
Additional tests were conducted using recordings of a pink noise sound source played through a loudspeaker at known distances from a single microphone. Recordings were played back at the same volume level using the playback format of FIG. 3 and the two stereo playback loudspeakers in the geometry as shown in FIG. 1 using the newly-derived azimuth playback equalization curves. Analogous to the above test method, relative distance was subjectively judged by comparing the recorded and played-back distances to an actual reference sound source such as a loudspeaker located at those same distances from the listener. A pan control sweeping the image from left to right verifies that the space between two stereo loudspeaker locations requires a progressively increasing augmentation of these outer ear cues for intracranial sense to restore distance perception for increasingly monauralized or centrally-placed images. That is, the redefined azimuth equalizations including frequencies above 1.5 kHz need to be increasingly emphasized for centrally located images, the degree of increase depending on the loudspeaker angle relative to the listener. This new finding for reproduced distance perception using two sound sources also generally matches prior single-sound-source angular hearing measurements that concluded directional azimuth cues are based only on intensity differences heard between the ears for frequencies above 1.5 kHz. This further corroborates the connection between distance perception and angular perception abilities.
It follows from this interrelationship and from the traits of sound propagation through air that the relative distance between a sound source and a microphone is inherently encoded in recordings as a function of the distance-related volume level and frequency content, or those sounds as modified by recording or mixing techniques. This distance information can be decoded by a listener's cognitive localization abilities provided its playback is properly interfaced to the listener's ears.
With such an interface, accurate vertical location decoding is also possible if (a) an actual recorded sound source is well above the ground surface where bass frequencies are more rapidly attenuated by the absence of a nearby reinforcing ground surface to limit omnidirectional dispersion, or (b) if a sound is equivalently recorded or mixed with higher relative amplitudes in and above the 7-8 kHz range. This frequency range is within a non-linear region of the Fletcher-Munson effect that at highest loudness levels becomes centered at ˜10 kHz, and is in this same region as the outer ear contributions made for vertically-displaced sound sources. Thus, the vertical cognition result likewise conforms to the relationship between the Fletcher-Munson effect, outer ear frequency alteration, and psychoacoustic localization ability. It also corroborates the correction in this high-frequency region seen in the STF curves as noted above.
From the above description, (a) the two-speaker format creates azimuth-related STFs that differ significantly from single sound source (HRTF) measurements in order to recreate correct angular image positions, and (b) the Fletcher-Munson effect plays an integral localization role in concert with these changes. When a single sound source is placed center-stage the sound common to both ears includes contributions from the outer ears that are reflected directly down the ear canals. These cues are dependent on the actual distance of the sound source to the listener or, in the case of a recording, on the actual distance between the sound source and the microphone or as those cues are modified by recording techniques.
Proper interfacing with the listener thus entails dynamic psychoacoustic corrections to the stationary location “signatures” of the two loudspeakers. In addition to perceptually amending the erroneous loudspeaker position cues, it necessitates appropriately engaging the listener's Fletcher-Munson/localization responses. This allows 3-D sound source position cues preserved in recordings to be correctly perceived.
The manner in which these interrelated aspects of cognition are simultaneously addressed for two-loudspeaker playback are schematically represented in the block diagram of FIG. 4A wherein left and right signal inputs are represented by terminals 39 and 40 and outputs by terminals 50 and 51 . The method incorporates three essential elements that operate in tandem dynamically. The resultant cognitive responses of the listener are dependent upon localization information intrinsically embedded within the audio signal sources as follows:
(1) channel balance-dependent phase-bandpass processes, represented by blocks 46 and 47 , together can accommodate phase and amplitude discrimination with a changing angle corresponding to channel balance relative to a human listener;
(2) a channel-mixing process dependent on channel balance, represented by block 41 , accommodates amplitude discrimination and cross-talk with changing angle relative to a human listener; and
(3) equalization, represented by blocks 44 and 45 , initially corrects head and outer ear anatomically related azimuth discrimination of loudspeaker locations.
During playback, the summed combination of steps dynamically alters the resultant phase, amplitude, and equalization of the outputs in real time according to the stereo source content, thereby simultaneously accommodating the Fletcher-Munson-related localization abilities of a human listener.
A non-dynamic adjustment for bass level is provided for resultant tonal balance to compensate for the loudspeaker location-related equalization setting.
In addition, the method can be modified to accommodate binaural recordings, as described below, by reducing inter-channel crosstalk and outer ear equalization while still providing requisite equalized loudspeaker location compensation. This option requires an additional method step:
(4) Optional channel balance-dependent subtractive signals that minimize monaural signal content, represented by block 52 .
FIG. 4B illustrates the circuitry corresponding to the components shown in the block diagram of FIG. 4A . Left and right signal inputs 39 and 40 , respectively, pass to an adjustable mixed bridge 41 that tracks channel balance. In FIG. 4B , this bridge is characterized as being equipped with a bridge/bypass selector switch 42 and a control 43 to vary the degree of cross-feed. This function may be implemented either actively or passively in hardware or in software by those skilled in the art. This stage of the process alters the incoming stereo signals prior to being input to left and right adjustable equalization stages 44 and 45 , respectively.
The two simultaneous mixed bridge functions are: (a) to provide proper distance perception of centrally-located images by reducing amplitudes of single channel signals relative to monaural signals (i.e., intracranial sense is increased for monaural signals), and (b) to compensate for excessive separations in mixed multi-microphone recordings which do not exist in normal free-field hearing circumstances by providing these separated stereo signals with the required cross-feed for intracranial sense and distance perception of side-located images.
The relative attenuation between single-channel and monaural inputs and the amplitudes of cross-feed mixing are dependent upon signal imbalance between both channels. For monaural signals, there is no cross-feed because both channel signals are identical. Maximum attenuation of the dominant channel and cross-feed to the opposite channel occurs when a signal is present in only the dominant channel.
A representation of the mixed bridge attenuation function, showing both channels relative to channel balance appears in FIG. 5A wherein an example of left-only, monaural-only, and right-only audio input levels is shown by solid line 55 . The corresponding mixed bridge left-only, monaural-only, and right-only output levels for the single channels are shown by dashed line 56 . No cross-feed effects on opposite channels are represented or included in this figure.
FIG. 5B shows a representation of the mixed bridge cross-feed function between both channels. An unmixed single channel input level is shown by solid circle 57 with zero output on the opposite channel. Corresponding mixed bridge output levels are indicated on the single attenuated and opposite cross-fed channel sides, respectively represented by circles 58 and 59 .
An example of the implementation of the mixed bridge providing these functions is shown schematically in FIG. 5C . The bridge/bypass selector switch 42 and cross-feed control 43 are in series with a limit resistor 66 . These are connected between resistors 67 and 68 in one channel and like resistors 69 and 70 in the opposite channel.
The diagram in FIG. 4B also incorporates left and right channel phase-shifted or phase-inverted cross-fed bandpass filters 46 and 47 the types of which are known to those skilled in the art. These filters have adjustable output levels as shown in FIG. 4B . By combining these crisscrossed, filtered, and phased signals with the mixed-bridged and equalized stereo signals as shown at the left and right channel summing stages 48 and 49 , respectively, amplitudes in left and right channel outputs 50 and 51 , respectively, vary according to channel balance within the 200 Hz-1.5 kHz frequency band while simultaneously satisfying the requisite azimuth curves. Output signals in this frequency band that are more monauralized are attenuated or cancelled relative to single-channel-only signals by the added out-of-phase cross-feed filter amplitudes.
An analog hardware implementation of the bandpass filters or its software equivalent requires a two-pole high-pass element and at least a six-pole or greater low-pass element. For analog filters, the degree of phase shift through the bandpass region will vary with frequency such that a trade-off between pass band frequencies and phase shifts are necessary. Alternatively, a digital “brick wall” finite impulse response (FIR) filter or its software equivalent can be used. This type of filter exhibits a constant phase within the bandpass region (for example, 180° out-of-phase with the corresponding equalized region) with an extremely steep low-pass roll-off.
Adjusted amplitudes for these phased cross-feed signals can vary considerably. Amplitudes depend on the angle subtended by the location of the loudspeakers relative to a listener and on recording characteristics such as channel separation, multi-microphone mixing and/or microphone separations. For either, reduced separation requires increased phased cross-feed.
The optional binaural playback method can be implemented, for example, by an apparatus summing stage 52 as shown in FIG. 4B and can be selected by switch 53 . Its output level is adjusted by a variable control 54 . It is intended for use with recordings made with two closely spaced microphones or a binaural head. The vast majority of recordings do not fall within this category.
Such recordings already contain considerable phase-shifted and/or out-of phase information, and additional outer ear and head shadow signatures in the binaural case, so the cross-feed out-of-phase amplitudes are correspondingly reduced. However, these recordings have substantial signal content common to both channels. This monauralized content must therefore be reduced relative to the mixed-microphone settings. In this case, the filters are fed to a summing stage 52 before mixing with the left and right equalized signals to further attenuate the monaural component within the 200 Hz-1.5 kHz frequency band. For binaural recordings, the low-pass roll-off must completely block all frequencies above 4 kHz in order to avoid interference with images placed behind the head.
Equalization settings are also correspondingly changed for these recordings. Frequencies greater than ˜1 kHz are tilted upward to compensate for reduced high-frequency separation during two-speaker playback. Even though outer ear contributions are already present for angularly- and vertically-displaced sound sources in a binaural recording, the speaker-placement correction is still required.
The equalization tilt for frequencies greater than ˜1 kHz similarly depends on speaker separation relative to the listener as well as loudspeaker traits. For example, wide-dispersion loudspeaker types need more high-frequency correction because they reduce high-frequency separation at the listener's ears.
Changes in high-frequency equalization and cross-feed levels in turn influence the relative volume setting for frequencies below 200 Hz in order to maintain tonal balance.
Generally, equalization settings above 1 kHz and cross-feed amplitudes both increase with reduced spacing between speakers relative to a listener, reduced separation in recordings, and broad-dispersion loudspeakers.
An example of the range of equalization adjustments for use in the process according to the invention in equalization stages 44 and 45 is shown in FIG. 6 , but does not necessarily represent the range limits for some actual situations. These modified settings for two-speaker playback differ from the pure azimuth curves for speakers placed to the sides of a listener because the dynamic process recovers the full forward 180° free-field of the listener. A typical range of equalization settings for frequencies below ˜200 Hz is shown by segments 60 and 61 . A range of filtered and phased cross-feed settings for various speaker geometries and separations in recordings is indicated by plots 62 and 63 . A range of typical equalization settings for frequencies above 1 kHz for various speaker types, loudspeaker geometries, and separations in recordings are indicated by plots 64 and 65 . The effects of altering the filtered and phased cross-feed amplitudes on the corresponding portion of equalization curves at 200 Hz-1.5 kHz are not shown. The overall gain can be adjusted using the equalization and filter level settings.
The subject invention is not limited to the particular details of construction, components, and processes described herein since many equivalents will suggest themselves to those schooled in the art. It is clear, for instance, that the application of the new STF azimuth parameters can be applied to any two-speaker stereo playback process for more accurate reproduction. Equally, applications of the above frequency and amplitude cues that elicit human localization responses can be applied to any such playback process incorporating these STFs. Further, the equalization process may be implemented using a conventional equalizer or a digital signal processor (DSP). Equalization, or the entire process, can be executed in software. Also, the optional binaural feature can be used as an additional compensation device for the frequency range 200 Hz-1.5 kHz when playback loudspeakers are very closely spaced relative to a listener. It will also be appreciated that portions of the equalization curve can be averaged. For example, the peaks and dips above 4 kHz can be averaged and centered generally around the 10 kHz region without departing from the spirit of this aspect of the invention.
|
An audio imaging method and cognition interface for two-loudspeaker playback is intended for use with standard stereo recordings. The process applies new azimuth-based equalization and phase measurements specifically derived for stereo playback while faithfully interfacing with and eliciting human psychoacoustic localization responses via the Fletcher-Munson loudness effect. The process accurately recovers and reproduces three-dimensional sonic image locations inherently encoded in standard recordings so that a listener may accurately perceive the three-dimensional sound. Sound images are reproduced in at least the forward 180° free-field environment of the listener. The apparatus is designed to allow reproduction of atypical recordings made with closely-spaced microphones if desired.
| 7
|
BACKGROUND OF THE INVENTION
The present invention relates to a throttle opening control device for a marine propulsion arrangement, and more particularly to a device which may be utilized in connection with the propulsion arrangement of an outboard motor, wherein the angle of throttle opening may be regulated, and automatically controlled, by an interconnection to the transmission shifting system.
The induction systems for many internal combustion engines frequently employ throttle valves. Throttle valves control the air flow through the induction passages of respective charge forming devices. The position of the throttle valves, and thus the amount of air inducted, may be controlled by an operator by way of a remote shift-type lever or a remote rotatable hand grip, for example, as upon the tiller of an outboard motor.
It has been known to interrelate the operation of such a throttle control arrangement with the operation of a transmission system, having forward, neutral, and reverse operating stages, in order to avoid certain problems. Problems might be incurred, for example, when attempting to start, or restart, an engine when the throttle is set for a high engine speed, or during an attempt to urgently shift the transmission into another operating stage during engine running conditions. The consequences of such problems might include quick and jerking water vehicle motions, tending to throw passengers off balance, or breakage of the shift control mechanism.
In certain prior types of marine propulsion devices, the transmission may be shifted from forward to neutral, or from reverse to neutral, only when the throttle opening angle is within prescribed safety limits. Also, the engine may be started only when the transmission is in the neutral stage. By employing such arrangements, the above-mentioned potential problems can be avoided.
The above-discussed prior art devices have, however, been recognized as lacking in operational efficiency in certain respects. For example, when operating an engine above idle speeds, before it is fully warmed up, stalling may occur. In accordance with the prior art devices, a two-step procedure must be carried out in order to restart the engine. First, the throttle must oftentimes be adjusted so that its opening angle falls within the prescribed safety limit, as it will likely have been moved outside such limit during operation. Next, the transmission must be shifted from the forward or reverse operating stage to the neutral operating stage. It is only at this point, then, that restarting may be initiated. Similarly, during usual running conditions in order to shift between the various transmission operating stages it is usually necessary, first, to decrease the throttle opening and, then, to make the desired shift. Thus, it is apparent that restarting, as well as shifting operations, can be a cumbersome procedure.
It is, therefore, a principle object of the present invention to provide an improved throttle opening control device for a marine propulsion arrangement.
It is a further object of this invention to provide a device which allows an operator of a marine propulsion unit to shift from a forward or reverse operating state into neutral, in order to start or restart an engine, or to effect an urgent transmission shift change during operation, without having to execute an independent step of separately reducing the throttle opening angle beforehand.
It is still a further object of this invention to provide a throttle opening control arrangement wherein the angle of throttle opening is automatically controlled by an interconnection to the transmission shifting system.
SUMMARY OF THE INVENTION
The present invention provides a throttle opening control arrangement adapted to be embodied in a marine propulsion unit. The invention comprises a transmission system having an operative driving stage and a neutral stage. A transmission system shift arrangement communicates with, and is operable to control, the transmission system. The invention further comprises an engine and an induction system. The induction system supplies a charge to the engine. A throttling arrangement is associated with the induction system for controlling the constitution of the charge. A throttle control arrangement is provided which communicates with the throttling arrangement and is operable to adjust a set throttle opening angle of the throttling arrangement. The invention additionally comprises a throttle position regulating system which interlinks the transmission system shift arrangement with the throttle control arrangement. The throttle position regulating system is operable to automatically determine a permissible range of throttle opening and, further, is operable to automatically decrease the angle of throttle opening upon shifting the transmission system from its operative driving stage to its neutral stage, solely in response to movement of the transmission system shift arrangement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a throttle opening control device constructed in accordance with the present invention and as embodied in an outboard-type marine propulsion unit.
FIG. 2 is a top plan view of the arrangement illustrated in FIG. 1.
FIG. 3 is an enlarged side elevational view of the throttle opening control device of the invention when the transmission of the marine propulsion unit is in its neutral operating stage.
FIG. 4 is a top plan view of the arrangement illustrated in FIG. 3.
FIG. 5 is an enlarged side elevational view of the throttle opening control device of the invention when the transmission of the marine propulsion unit is in its forward operating stage.
FIG. 6 is an enlarged side elevational view of the throttle opening control device of the invention when the transmission of the marine propulsion unit is in its reverse operating stage.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring initially to FIGS. 1 and 2, a side elevational view and a top plan view are shown, respectively, of a throttle opening control device constructed in accordance with the present invention, and as embodied in an outboard motor type marine propulsion unit. Such an embodiment is typical of the environments in which the invention can be utilized. It is to be understood, however, that the invention can be employed in conjunction with other propulsion arrangements, such as an inboard-outboard watercraft propulsion system, and with other uses for internal combustion engines and their throttle valve mechanisms.
In the illustrations, the outboard motor is identified generally by the reference numeral 2. The outboard motor 2 includes a power head consisting of an internal combustion engine 4 and a surrounding protective cowling 6. The engine may be of any known type; for example, an engine operating on the twostroke crankcase compression principle would be suitable.
As is conventional with outboard motor practice, the engine 4 is disposed so that its output shaft (not shown) rotates about a vertically extending axis and is coupled to a drive shaft (not shown) that is journalled within a drive shaft housing 8. A lower unit (not shown), which is located beneath the drive shaft housing 8, contains a forward, neutral, reverse transmission (not shown) so that the drive shaft may drive a propeller (not shown) in selected forward and reverse directions, as is well known in this art. It is to be understood that the invention may also be practiced with a transmission provided with other than solely a forward, neutral and reverse gear system.
The engine 4 is supplied with charge forming devices 10 which are depicted as being of the carburetor type and include respective butterfly-type throttle valves 12 which are affixed to throttle valve shafts for movement thereabout. A manually controlled throttle linkage system cooperates with the carburetors 10 for controlling their throttle valves 12. The throttle linkage system includes a throttle rod 14 which is connected to a lever 15 which drives one of the throttle valves 12, which is a directly driven throttle valve. Movement of the throttle rod 14, thus, controls the rotational movement of the driven throttle valve. The further throttle valve 12 is a slave valve and its rotational movement is controlled by a further linkage arrangement 16 emanating off of the driven valve. The throttle rod 14 is connected to one end of a generally L-shaped throttle control lever 18 and is, in turn, driven by the movement of the L-shaped throttle control lever 18 which is pivotal about a shaft 20. The other end of the L-shaped throttle control lever 18 is connected to a throttle control cable 22. Movement of the control cable 22 may be manually determined by a remote, operator controlled throttle device, such as a rotatable tiller handgrip 24. The degree of throttle opening is adjusted in proportion to the degree of rotation of the throttle control lever 18. It should be noted that the throttle control lever could be of a directly driven type instead of remotely operated.
Next, the throttle opening control arrangement 26, wherein the angle of throttle opening is automatically controlled by an interconnection to the transmission shifting system, as contemplated by the present invention, will be discussed.
As shown in FIGS. 1 and 2, a remote transmission shift lever 30 is provided along a forwardly located area of the marine propulsion unit 2, with respect to an associated watercraft (not shown). The transmission shift lever 30 is positioned in such a manner that it is readily accessible to an operator for running the watercraft. A shift control cable 32 mechanically interlinks the shift lever 30 with a slider member 34 which is disposed for linear reciprocal movement along a guide 36.
A shifting apparatus 38 is disposed beneath the slider member 34 and associated guide 36. The shifting apparatus 38 operates to shift the transmission of the propulsion unit 2 between its various operating stages (e.g., forward, neutral and reverse) by way of a rotating movement of the shifting apparatus 38. A shift rod lever 40 extends outwardly and upwardly of a generally vertically extending shaft of the rotatable transmission assembly 38. An elongate shift plate 42 mechanically interlinks the slider member 34 and the shift rod lever 40 so that linear movement of the slider member 34 imparts a rotational movement to the shift rod lever 40 via the shift plate 42. As just described, such rotational movement of the shift rod lever 40 ultimately effects gear changes within the transmission of the propulsion unit 2 by rotating the shift device 38.
With additional reference to FIGS. 3 and 4, which show the throttle opening control device of the invention when the transmission of the marine propulsion unit is in its neutral operating state, it can be seen that the throttle control lever 18 is located beneath the slider member 34 for rotation about an axis defined by shaft 20. A throttle stopper member 46 is also disposed beneath the slider member 34 and is rotatable about the axis defined by the shaft 20. A projection 48 is located to one end of the throttle stopper member 46. The projection 48 is provided with a threaded hole therethrough for receiving a bolt member 50. The bolt member 50 is a set bolt which is adjustable via its rotation within the threaded hole so that the throttle opening angle may be regulated, as will be described below.
A connecting rod 52 mechanically interlinks the slider member 34 and the throttle stopper member 46 so that the position of the throttle stopper member 46 about its axis of rotation, and thus the disposition of the associated projection 48 and set bolt 50, can be determined according to the position of the slider member 34. The throttle control member 18 is provided with a stepped portion 56, having a working face region 58, along its lower end. The working face 58 is disposed so that it will contact an abutting end of the set bolt 50, under certain operating conditions to be discussed, which will impede further rotational movement of the throttle control member 18 in a direction tending to increase the angle of throttle opening. In this way, a limited angle of rotation for the throttle control lever 18 can be set. By adjusting the position of the set bolt 50, via its rotation within its threaded holder, this angle can be fine tuned within a range determined by the adjusting length of the set bolt 50.
Next, the operation of the throttle opening control device 26 under dynamic operating conditions, wherein the transmission is operated initially in forward, then to neutral, and finally to reverse, will be set forth.
FIG. 5 is a side elevational view of the throttle opening control 26 device when the transmission is in its forward operating state. The slider 34, which is reciprocally movable in a linear fashion backwards and forwards along the guide 36, is located towards the right hand side of the guide 36 in the forward operating state, when viewed in the direction of FIG. 5. The connecting rod 52 acts upon the throttle stopper 46 tending to pull the throttle stopper 46, and its associated set bolt 50, in a direction upwardly and away from the working face 58 of the step 56. Thus, the angle available for throttle opening, defined by the angular distance between the abutting face of the set bolt 50 and the working face 58 of the step 56 about the central axis of the shaft 20, is set as shown by the reference letter f. Accordingly, the throttle control lever 18 can be rotationally adjusted, via the remote, operator throttle control 24, through the angle f during forward operation of the marine propulsion unit 2.
With reference, once again, to FIGS. 3 and 4, the slider 34 becomes positioned centrally along the guide 36 when the transmission is shifted from forward into the neutral operating state. Such movement of the slider 34 causes the throttle control lever 18 to move downwardly by way of the resultant simultaneous movement imparted to the connecting rod 52 located therebetween. If the throttle's position during forward operation, just prior to the shifting of the transmission into neutral, was outside the permitted angular position for neutral operation, the abutting end of the set bolt 50 will contact the working face 58 of the step 56. It is by such contact that the throttle positioning is automatically controlled by shifting of the transmission. In such a case, the throttle control lever 18 will be automatically rotated around towards its closed position, without any independent manual operation of the throttle arrangement. Once in neutral, the angle of permitted throttle movement is that depicted by the reference letter n in FIG. 3, which is, likewise, defined by the angular distance between the abutting face of the set bolt 50 and the working face 58 of the step 56 about the central axis of the shaft 20.
FIG. 6 is a side elevational view of the throttle opening control device 26 when the transmission is in its reverse operating state. The slider 34 is located towards the left hand side of the guide 36 in the reverse operating state, when viewed in the direction of FIG. 6. The connecting rod 52 acts upon the throttle stopper 46 tending to pull the throttle stopper 46, and its associated set bolt 50, in a direction upwardly and away from the working face 58 of the step 56 when the transmission is shifted from neutral into reverse. Thus, the angle available for throttle opening, defined by the angular distance between the abutting face of the set bolt 50 and the working face 58 of the step 56 about the central axis of the shaft 20, is set as shown by the reference letter r. Accordingly, the throttle control lever 18 can be rotationally adjusted, via the remote, operator throttle control 24, through the angle r during reverse operation of the marine propulsion unit 2.
In addition to the advantages detailed above, the present invention avoids certain transmission shifting errors wherein forces acting in concert with the normal forces involved in effecting a shift result in the inadvertent achievement of an undesired shifting posture. For example, when the throttle is opened, an external force may be imposed, via the connecting rod 52, upon the slider 34. An external force acting upon the slider 34 could conceivably result in a mistaken shift. According to the present arrangement, however, the external force imposed by the connecting rod 52 extends in a direction which is generally perpendicular to the direction of the operational reciprocal movement of the slider 10. Thus, the force transmitted by way of the connecting rod 52 does not have a directional component sufficient to cause a mistaken shift.
Additionally, when the propulsion unit 2 is run in its reverse mode of operation other potential problems are existent. For example, if the throttle is opened to a rather high degree, the propeller might impose a strong thrust force in a direction which opposes a tilt or trim device force tending to angle the propulsion unit somewhat upward. If the propeller thrust force overcomes the tilt or trim device force, the desired tilt or trim angle might become inadvertently decreased. According to the present arrangement, the regulated angle available for opening the throttle during reverse operation, denoted by the reference letter r in FIG. 6, is set so that the propeller thrust force during reverse operation will not be able to overcome the holding force supplied by a tilt or trim device.
It is to be understood that the foregoing description is primarily intended to be exemplary, in particular to provide the preferred embodiment of the invention as contemplated by the inventor, and is not meant to be limiting. Accordingly, various changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims.
|
The present invention provides an improved throttle opening control device for a marine propulsion arrangement. The invention allows an operator of a marine propulsion unit to shift from a forward or reverse operating state into neutral, in order to start or restart an engine, or to effect an urgent transmission shift change during operation, without having to execute an independent step of separately reducing the throttle opening beforehand. According to the present invention, the angle of throttle opening is automatically controlled by an interconnection to the transmission shifting system of the propulsion arrangement.
| 1
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable.
STATEMENT CONCERNING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
FIELD OF THE INVENTION
[0003] The invention relates to fabrics for manufacturing non-woven textiles and paper products.
BACKGROUND OF THE INVENTION
[0004] Non-woven textiles, or simply “non-wovens”, are well-known products formed from webs of randomly arranged and entangled fibers. In most cases, the fibers of non-wovens are bonded to each other, for example, adhesively, mechanically, thermally, or chemically. Non-wovens may be single use products with relatively low strength, such as hygienic wipes and the like. Non-wovens may also be stronger and more durable products, such as medical gowns and geotextiles.
[0005] Processes for forming non-wovens typically involve forming the fiber web on a structure of interwoven yarns, typically referred to as a forming fabric. These processes include, for example, wet forming, carding, spunbonding, and meltblowing. In both spunbonding and meltblowing processes, the fibers are formed of a molten polymer that is extruded through a die and eventually collects on the forming fabric. The molten polymer may be, for example, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), or copolymers of PET and PE, and the forming fabric is typically formed of PET yarns.
[0006] Both spunbonding and meltblown processes can occasionally produce drops of the molten polymer that adhere to the forming fabric. In some cases, adherence and accumulation of the molten drops can cause blemishes, burn holes, or other surface defects on the forming fabric. These defects can reduce the quality of non-wovens formed on the forming fabric; for example, a damaged forming fabric can create products with relatively rough surfaces or other undesirable characteristics. In most cases, it is easiest to replace a defective forming fabric with a new forming fabric.
[0007] Further still, in some cases the molten polymer drops can penetrate the web-facing side and accumulate within the fabric, thereby reducing the permeability and the usefulness of the fabric. Certain well-known chemicals, such as sulfuric acid (H 2 SO 4 ) for PET and toluene or methyl ethyl ketone (MEK) for PE, could be used to dissolve the polymer drops; unfortunately, such chemicals would also damage the PET yarns of the forming fabric. As a result and as described above, it is easiest to replace a defective forming fabric with a new forming fabric.
[0008] Considering the limitations of previous fabrics, it would be desirable to have a fabric with heat resistance to resist damage from molten polymer drops produced in some non-woven forming processes. It would also be desirable for such a fabric to resist corrosion from common chemicals, such as chemicals that dissolve the polymer residues but do not harm the base fabric. Further still, it would also be desirable for such a fabric to dissipate static electricity in some cases; that is, it would be desirable for such a fabric to act as an antistatic fabric. Further still, it would be desirable for such a fabric to have a smooth upper surface, including in some cases, the seam between ends or different sections of the fabric.
SUMMARY OF THE INVENTION
[0009] In one non-limiting aspect, the present invention provides a fabric for supporting a fibrous web. The fabric comprises a layer that includes a plurality of weft yarns and a plurality of warp yarns interwoven with the plurality of weft yarns. The warp and weft yarns define a web-facing side and an opposite machine-facing side. The warp yarns comprise at least one of polyphenylene sulfide (PPS) and polyetheretherketone (PEEK). In addition, a yarn count, weave pattern, and yarn shape of the fabric are configured such that molten polymer drops are scrapable from the web-facing side leaving a support surface that does not blemish a fibrous web supported by the fabric.
[0010] In another non-limiting aspect of the invention, the fabric comprises a layer that has a web-facing side and a machine-facing side. The layer includes a plurality of weft yarns that comprise at least one of polyphenylene sulfide (PPS) and polyetheretherketone (PEEK). The layer further includes a plurality of warp yarns interwoven with the plurality of weft yarns. The warp yarns comprise at least one of PPS and PEEK. At least some of the warp yarns define floats over at least five consecutive weft yarns and have flat upper surfaces such that molten polymer drops do not penetrate an upper plane of the web-facing side.
[0011] The foregoing and other objects and advantages of the invention will appear in the detailed description which follows. In the description, reference is made to the accompanying drawings which illustrate a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
[0013] FIG. 1 shows an exemplary weave repeat of a fabric according to the invention;
[0014] FIG. 2 is a schematic representation of the weave pattern of individual warp yarns with weft yarns of the fabric of the invention;
[0015] FIG. 3 is a side view of the weave pattern of several warps yarns with several weft yarns;
[0016] FIG. 4 is a view of a machine-facing side of the fabric of the invention;
[0017] FIG. 5 is a top view of a spiral or “spiro-pin” seam connecting ends of the fabric of the invention;
[0018] FIG. 6 is a side view of one end of the spiro-pin seam and the fabric of the invention; and
[0019] FIG. 7 is a top view of a double loop pin seam connecting ends of the fabric of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The particulars shown herein are by way of example and only for purposes of illustrative discussion of the embodiments of the invention. The particulars shown herein are presented to provide what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for the fundamental understanding of the invention. The description taken with the drawings and photographs should make apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
[0021] It is noted that while the discussion of the invention that follows may refer specifically to forming fabrics in the non-wovens industry, the invention is applicable to other fabrics in the papermaking industry and other industrial applications. For example, the fabric of the invention may be used as an oven fabric or a dryer fabric on a papermaking machine.
[0022] Further, when an amount, concentration, or other value is given as a range of preferable upper values and preferable lower values, this should be understood as specifically disclosing all ranges formed from any combination of a preferable upper value and a preferable lower value, regardless of whether ranges are separately disclosed.
[0023] Referring to FIGS. 1-7 , the fabric of the invention includes a layer 10 , such as the base layer of the fabric, that has a web-facing side 12 and a machine-facing side 14 . The layer 10 comprises interwoven warp (machine direction) yarns and weft (cross-machine direction) yarns. By way of non-limiting example, FIGS. 1-7 show a fabric having one layer of weft yarns. However, it is contemplated that the fabric may include any number of layers of weft yarns. Those skilled in the art would modify the number of layers based on any number of parameters, such as fabric length, weight and strength requirements, desired permeability, the type of product being produced, and the like. By way of non-limiting example, the fabric preferably has from one to three layers of weft yarns, and most preferably one or two layers of weft yarns.
[0024] Each warp yarn is made of a high temperature thermoset polymer; preferably polyphenylene sulfide (PPS), although polyetheretherketone (PEEK) may be used in some embodiments. In some embodiments, each warp yarn is a monofilament yarn made of extruded PPS or PEEK polymeric resin material plus any other appropriate material used in the manufacture of industrial process fabrics and paper machine clothing. However, each warp yarn may be a plied monofilament or the like. Each weft yarn is also preferably made of PPS, although in some embodiments PEEK or polyester may be used, and is a monofilament, plied monofilament, or the like.
[0025] Warp and weft yarns comprising PPS and/or PEEK advantageously provide a heat-resistant fabric layer 10 . As such, the web-facing side 12 and other parts of the fabric layer 10 resists blemishes and damage caused by molten polymer drops occasionally formed during certain processes, such as spunbonding and meltblowing. Instead, the molten drops solidify on the web-facing side 12 and typically do not adhere to the fabric. However, an operator may use a scraper to remove any residual polymer drops that adhere to the fabric without damaging the fabric. As a result, the fabric does not form blemishes on the non-woven web after residual polymer drops are removed from the fabric. In addition, warp and weft yarns comprising PPS and/or PEEK advantageously provide a fabric layer 10 that resists corrosion caused by well-known cleaning chemicals, such as sulfuric acid for PET, solvents such as toluene or methyl ethyl ketone (MEK) for PE, or sulfuric acid followed by MEK for copolymers of PET and PE. As a result, instead of using a scraper, an operator may use these chemicals to dissolve any residual polymer drops without damaging the fabric.
[0026] In some embodiments, some of the weft yarns are antistatic yarns in order to provide a fabric layer which dissipates static electricity that accumulates during some dry forming processes. The antistatic yarns may be formed of carbon-impregnated nylon, metal, conductive PPS or conductive PEEK and conductive nylon using techniques described in U.S. Pat. No. 7,094,467, the disclosure of which is hereby incorporated by reference in its entirety. In these embodiments, the fabric may also include additional features, such as conductive edging, to form an electrostatic grid that dissipates static electricity.
[0027] It is contemplated that the fabric layer may use differing shapes and sizes for the yarns. For example, the warp yarns may have a greater thickness than the weft yarns, or vice versa. In some embodiments, the warp yarns may be round or circular with diameters in the range of 0.10 mm to 1.20 mm. However, in a preferred embodiment, the warp yarns have flat upper surfaces 16 ( FIG. 3 ) that define a large portion of the web-facing side 12 . The flat upper surfaces 16 may be formed by grinding the web-facing side 12 of the fabric, or, preferably, by using warp yarns with rectangular cross-sections. The rectangular warp yarns, if used, preferably have width and height dimensions in the range of 0.40 mm to 1.20 mm, and are most preferably 0.63 mm wide by 0.37 mm high. These preferred shapes and sizes advantageously reduce the mesh (number of warp yarns per inch) of the fabric by one half compared to previous designs.
[0028] The flat upper surfaces 16 of the warp yarns provide a sufficiently solid and flat support surface on the web-facing side 12 from which polymer drops can be removed easily with a scraper. That is, the molten polymer drops do not penetrate an upper plane of the fabric. The term “upper plane” should be understood to mean a plane beyond which polymer drops would create a mechanical form fit or wrap around yarns of the fabric. For example, the upper plane for a layer of round yarns would pass through the centers of the yarns. In contrast, the upper plane for a layer of rectangular yarns is at the bottom surface of the yarns. In any case, polymer drops cannot be removed easily with a scraper if the polymer drops flow past the upper plane, and an attempt to do so may damage the fabric. As a result, the surface tension of the polymer drops is preferably considered and the shapes and spacing between yarns are selected such that the polymer drops do not penetrate the upper plane of the fabric.
[0029] The weft yarns may be, for example, circular, oval-shaped, circle-like or oval-like as shown in FIGS. 3 and 6 . The weft yarns preferably have a diameter in the range of 0.10 mm to 1.20 mm and most preferably 0.70 mm. In embodiments in which some of the weft yarns are antistatic yarns, the antistatic yarns preferably have a diameter in the range of 0.10 mm to 1.10 mm and most preferably 0.28 mm.
[0030] In a preferred embodiment, the warp and weft yarns are woven as shown specifically in FIGS. 1-4 . FIG. 1 shows a single repeating pattern area, or a “weave repeat”, of the fabric layer that encompasses four warp yarns (yarns 1 - 4 extending vertically in FIG. 1 ) and eight weft yarns (yarns 1 - 8 extending horizontally in FIG. 1 ). In some embodiments, some of the weft yarns, for example, the even-numbered weft yarns, are antistatic weft yarns as described above. In FIG. 1 , the symbol ‘X’ represents a position where a warp yarn passes over a weft yarn (e.g., warp yarn 1 passes over weft yarn 2 ) as viewed from the web-facing side of the fabric. Conversely, an empty box represents a position where a warp yarn passes under a weft yarn (e.g., warp yarn 1 passes under weft yarn 1 ) as viewed from the web-facing side of the fabric. FIG. 2 depicts the paths of warp yarns 1 - 4 as they weave with weft yarns 1 - 8 . While FIGS. 1 and 2 only show a single section of the fabric, those of skill in the art will appreciate that in commercial applications the pattern shown in FIGS. 1 and 2 would be repeated many times, in both the warp and weft directions, to form a large fabric suitable for creating non-wovens.
[0031] Referring to FIGS. 1 and 2 , each warp yarn weaves the same pattern with the weft yarns. That is, each warp yarn passes over five consecutive weft yarns, and then passes under three consecutive weft yarns. For example, warp yarn 1 passes over weft yarns 2 - 6 , and then passes under weft yarns 7 , 8 , and 1 . However, it should be noted that the pattern is offset between adjacent warp yarns; specifically, the pattern of one adjacent warp yarn is offset by four weft yarns, and the pattern the other adjacent warp yarn is offset by two weft yarns. For example, the last weft yarn passed over by warp yarn 2 is weft yarn 2 , the last weft yarn passed over by warp yarn 1 is weft yarn 6 (i.e., an offset of four weft yarns), and the last weft yarn passed over by warp yarn 3 is weft yarn 4 (i.e., an offset of two weft yarns).
[0032] Each warp yarn defines a long warp float by passing over five consecutive weft yarns. These warp floats define a large portion of the web-facing side. Further still, the long warp floats advantageously contribute to the smoothness of the web-facing side. As described above, the smooth web-facing side permits polymer drops to be removed easily. It is also contemplated to use warp floats of other lengths because warp floats of any length (i.e., passing over two or more consecutive weft yarns) advantageously provide a web-facing side with some degree of smoothness. However, it is preferred to use warp floats that pass over less than six consecutive weft yarns to ensure that the fabric layer is relatively stable.
[0033] As described above, the long warp floats define a large portion of the web-facing side. However, weft floats that pass over two consecutive warp yarns (e.g., weft yarn 5 passes over warp yarns 2 and 3 ) also define a portion of the web-facing side. The weft floats are recessed compared to the long warp floats, and as a result, the weft floats define pockets on the web-facing side. The short length of the weft floats and pockets advantageously provide a sufficiently solid and flat support surface that prevents polymer drops from penetrating the upper plane of the web-facing side and creating a mechanical form fit with the fabric. Instead, polymer drops remain on the web-facing side and can be removed easily.
[0034] The fabric of the invention preferably has a permeability in the range of 50 cfm to 1200 cfm and most preferably about 500 cfm. The fabric preferably has a caliper in the range of 1 mm to 4 mm and most preferably about 1.5 mm. However, those skilled in the art will appreciate that the aforementioned characteristics depend on the yarn shape, yarn size and the weave pattern. As a result, appropriate permeability and caliper ranges may vary depending on the specific fabric design.
[0035] The fabric of the invention may be formed as an endless belt without using additional components. However, in some embodiments, a well-known seam connects ends of the fabric layer to form a belt. Referring to FIGS. 5 and 6 , the fabric preferably includes a spiral or “spiro-pin” seam 18 to connect the ends of the fabric. Referring to FIG. 6 , one side of the spiro-pin seam 18 includes first and second anchor yarns 20 and 22 that support a spiral yarn 24 that extends in the weft direction. The first anchor yarn 20 also supports portions of the warp yarns proximate the seam 18 , and the portions of the warp yarns are rewoven with adjacent weft yarns. Referring to FIG. 5 , the spiral yarn 24 meshes with a second spiral yarn 26 on the opposite end of the fabric to form the endless belt.
[0036] In some embodiments, the seam may be a single loop seam; such a seam is well-known to those skilled in the art. Further still, in some embodiments, the seam may be a double loop pin seam 28 as shown in FIG. 7 . The double loop pin seam 28 includes first and second anchor yarns 30 and 32 that support first and second offset yarn loops 34 and 36 on each end of the fabric layer. The first and second yarns loops 34 and 36 are formed from portions of the warp yarns, and each weave repeat includes one set of first and second yarn loops 34 and 36 . Other aspects of double loop pin seams are well-known to those skilled in the art. Regardless of the type of seam used, the seam preferably has the same permeability and caliper as other areas of the fabric to provide a non-marking fabric belt. In addition, the components of the seam (e.g. the anchor yarns and the spiral yarns) are preferably made from the same material as the warp and weft yarns (e.g., PPS or PEEK) to prevent damage from polymer drops and corrosion from cleaning chemicals.
[0037] The fabric layer of the invention is preferably manufactured as follows: first, the warp and weft yarns are woven using well-known techniques. The fabric is unstable and the yarns do not mesh well with one another after weaving because yarns formed from PPS and/or PEEK are relatively rigid compared to other types of yarns. The fabric is heat set and stretched to address this issue, and the yarns mesh with one another to provide a stable fabric. Next, if the fabric is to include a seam, yarns proximate the ends of the fabric are fringed and the warp yarns are rewoven with the seam components and the weft yarns. The fringed yarns are then clipped flushly with the web-facing or machine-facing side of the fabric to maintain the smoothness of the fabric. Finally, the seam is heat set so that the seam is in-line with other areas of the fabric and to ensure the seam is non-marking.
[0038] From the above disclosure it should be apparent that the fabric of the present invention can provide any combination of the following advantages: heat resistance and resistance to damage from molten polymer drops; corrosion resistance to chemicals that dissolve polymer drops; light weight and high strength; high permeability; and use of a heat and corrosion-resistant non-marking seam.
EXAMPLE
[0039] A fabric for a non-wovens application was woven on a loom utilizing Voith's weave pattern #24 plus a stuffer. The fabric included rectangular PPS warp (machine direction) yarns that were 0.63 mm wide by 0.37 mm high at 44 ends per inch. The weft (cross-machine direction) yarns had a diameter of 0.70 mm and alternated with 0.28 mm diameter carbon-impregnated nylon antistatic yarns at 30 picks per inch. The fabric was heat set at 480 degrees F. and stretched to 30 pli. The fabric was cut to length and then prepared for seaming. PEEK spiral yarns were installed at both ends and joined. The fabric was then cut to finished width and heat sealed. A carbon loaded adhesive was applied over a width of 1″ along both edges. The carbon edge formed an electrostatic grid to dissipate static electricity accumulated during formation of non-wovens or paper products.
[0040] It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to exemplary embodiments, it should be understood that the words that have been used are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the invention has been described herein with reference to particular arrangements, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein. Instead, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.
|
A fabric for supporting a fibrous web is disclosed. The fabric has a layer that includes a plurality of weft yarns and a plurality of warp yarns interwoven with the plurality of weft yarns. The warp and weft yarns define a web-facing side and an opposite machine-facing side. The warp yarns include at least one of polyphenylene sulfide (PPS) and polyetheretherketone (PEEK). In addition, a yarn count, weave pattern, and yarn shape of the fabric are configured such that molten polymer drops are scrapable from the web-facing side leaving an upper support surface that does not blemish a fibrous web supported by the fabric.
| 3
|
REFERENCES CITED
U.S. patent Document Nos. 3,883,750, 5/1975--Uzzell, 4,012,163, 3/1977--Baumgartner, 4,088,419, 5/1978--Hope, 4,116,581, 9/1978--Bolie, 4,127,356, 11/1978--Murphy, 4,140,433, 2/1979--Eckel, 4,204,126, 5/1980--Diggs, 4,254,843, 3/1981--Han 4,278,896, 7/1981--McFarland, 4,302,684, 11/1981--Gogins.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This device relates to an augmented turbine power plant that extracts energy from a moving stream such as a river, an ocean current, and the wind.
2. Description of Prior Art
Wind, ocean currents, and rivers have long been recognized as sources of alternate energy. Two groups of devices lead the state of the art for converting moving stream energy to useful electrical or mechanical energy.
The more recent and current leader in the state of the art in wind energy conversion is the twin blade device. It consists of specifically shaped propellar blades pivoted at the top of a support structure. The shape of the blades cause a circulation in the air stream around the blades which produces rotation. However these blades work efficiently at only high tip speeds. These devices are impractical for underwater use and sites with lower average wind velocities.
The larger the blades become, the lower the rotations per minute and requires less efficient high gearing ratios to a generator.
The augmentation of a sawmill waterwheel by constructing a dam across a stream is the oldest representative of the second group of devices. The modern versions are hydroelectric dams. However dams are impractical in wind and ocean currents. Dams require massive investment, are only feasible at a few sites, and cause considerable damage to the environment. Several recent attempts have been made to augment a turbine to eliminate the inadequacies of the current leaders in the state of the art. Murphy's "Wind Motor Machine" demonstrates many of the problems with augmenting a turbine in a free stream. A converging tube augmenter focuses more of the wind than would effect the turbine without the tube. However the tube requires considerable structural support to obtain large volumes of wind and must be rolled around tracks at ground level. This places the mouth of the tube in the slowest velocity stream present at a site due to ground drag effects. Uzzell's "Method and Apparatus for Generating Power From Wind Currents" elevates a Venturi tube type augmenter above ground drag effects, however the support structure required to elevate the augmenter makes it uneconomical for large volumes of wind required in a slow moving stream. McFarland's "Wind Power Generator" uses a shield to improve efficiency of a verticle axis turbine. However the structural requirements of the shield and turbines and the ground drag effects on the turbine results in similar shortcomings as Murphy's device. Hope's "Wind Operated Power Plant" uses an airplane wing type augmenter and a vertical construction efficiency. However the turbines interfere with the circulation required by the wing augmenters to perform their function. Other patents referenced are less promising than those devices discused above.
SUMMARY OF THE INVENTION
New and Different Function
I have invented a device with a new and different augmenter system. The augmenter circulates and focuses portions of the moving stream which produces the same conditions as tube type augmenters but with far lower structural requirements. The turbine does not interfere with the circulating function of the augmenter and the augmenter does not require high tip speed and is efficient at all wind or water speeds. This makes the device feasible at low wind velocity sites and underwater. An elevated horizontal axis turbine and augmenter system placed out of the effects of ground drag make more energy available to the device.
OBJECTS OF THE INVENTION
An object of the invention is to extract usable energy from moving streams such as wind, rivers, and ocean currents. Further objects are to achieve the above with a device that is durable yet economical to build and maintaine.
The specific nature of the invention, as well as other objects, uses, and advantages therof, will clearly appear from the following description and from accompanying drawings, the different views of which are not scale drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of the device in a moving stream
FIG. 2 is a schematic of augmenter system geometry
FIG. 3 is a top view of the device in a moving stream
FIG. 4 is a side view of the device in a moving stream
FIG. 5 is a sectional view taken from FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 refers to the front view of the device claimed when viewed by an observer located upstream of the device. Ground 10 can be the grade level at a wind energy site or ocean floor. A single pylon support structure 11 is provided and buried as required as required by structural requirements. The invention is not limited to this particular design of support structure. On top of support structure 11, rotational platform 29 has support truss 15 and support truss 16 mounted on 29 to hold right base augmenter 13 and left base augmenter 14 in an outstreached position. The governor augmenter 12 is attached to platform 29 by a hinge connection 26 hidden from this view behind 29. Right throat augmenter 17 and left throat augmenter 18 are held in position by similar frame structure as 15 and 16 and held at one attack angle by stream splitter support 27. In combination 15, 17 and 27 form a triangular truss with a high strength to weight ratio. Similarly on the left side 16, 18, and 27 form another high strength truss. Rotating platform 29 is covered by nacelle 21 which has journal bearings 23 and 24 mounted on 21. Journal bearings 22 and 25 are supported on top of truss 15 and 16 respectively. Rotating shaft 30 turns inside journals 22,23 24, and 25. Turbine 19 and turbine 20 are mounted on shaft 30. Although American savonus type turbines are shown, this does not limit the invention to this one turbine design. Right base augmenter 13 in combination with governor augmenter 12 are positioned in the moving stream to create overpressure in front of the augmenters and underpressures downstream of each augmenter such that angular momentum is added to produce clockwise circulating stream 41,42,43. Left base augmenter 14, and governor augmenter 12 produce counter clockwise circulation 45,46,47. In higher viscosity moving streams smaller sub-augmenters a,b,c,d,e,67,g,h,i,j,k,l,68, and n are provided to add drag produced circulation to enhance base and governor circulation producing function. The relative position between the turbine system and augmenter system is not limited to this one embodiment for the invention. In highly predictable ocean currents turbines and augmenter may be mounted on seperate support structures. FIG. 2 provides a geometric description of the augmenter system prefered embodiment to achieve the other primary function of the augmenters, focusing the circulating streams downstream of the device. With 40 indicating a moving stream direction and axis 50 represents the axis of a right circular cone 60 is oriented parallel to stream direction 40 with cone focus 52 downstream of cone base 51. Planes 53,54, and 55 cut through the cone at different angles forming hyperbolic surface 56, parabolic surface 57, and elliptical surface 58 respectively. In the prefered embodiment, the augmenter system is shaped and held in position in the moving stream by the support structure to form elliptical surface 58, with governor 12 having a focus at 61, throat augmenters in combination having focus 59, and in combination base, throat and governor augmenters have a common focus 52. The circulating streams produced by the base and governor augmenters come under the cone shaped underpressure zone behind the augmenter system and are focused toward the cone axis 50 and cone focus 52.
FIG. 3 represents a top view of the device in moving stream 40 directed from bottom to top. Right throat augmenter 17 and left throat augmenter 18 having leading edge 65 shaped similar to the leading edge of the elliptical surface shown in FIG. 2. Governor augmentor 12 has trailing edge 66 similar to the elliptical surface trailing edge shown in FIG. 2. The edges of the base augmenters also are extended to points 67 and 68 such that all portions of moving stream 40 going around and behind the augmenter system converge toward common focus 52. Clockwise circulating stream 41,42,43, with its axis of rotation previously paralled to moving stream direction 40 is turned by the focusing effect of the augmenter system at position indicated by circulating stream 70.71,72 with axis of rotation 90 becoming nearly perpendicular to stream direction 40. Further downstream this circulating stream converges toward common focus 52 at locations 76,77,78. In a similar manner counterclockwise stream 45,46,47, axis of rotation is turned to 73,74,75, with axis 91 and later downstream toward common focus 52 at 79,80,81. Right throat augmenter 17 in combination with left throat augmenter 18 focus streams 85,86,87,88,90 into turbines 19 and 20. Nacelle 21 has streamline shape to improve stream flow through the turbine system.
FIG. 4 shows a side view of the device with moving stream 40 direction left to right. Support structure 11 is indicated in ground 10 to support the augmenter and turbine system and resist the overturning moment caused by moving stream forces on the augmenter system, turbine system, and support structure. Governor augmenter 12 is attached to rotational platform 29 by hinge 26 at the furthest point downstream on 29. The drag force on 12 maintains the downstream position of it automatically during a change in stream direction. This also helps keep the turbine system axis perpendicular to moving stream direction 40. The nacelle 21 and interior of platform 29 are sectioned at 5 and provided in FIG. 5. Moving stream direction 40 which can be a representation of wind or ocean current observes physical laws similar to a slow moving incompressible fluid. The focused circulation 70,71,72 rotates with an axis almost perpendicular to moving stream 40. A higher mass flow rate is produced in the area above 70,71,72 which decreases the backpressure below and downstream of turbine 19 resulting in improved performance. The reduced pressure behind the turbine system allows the portion of the stream influencing the turbine system 100,101,102,103, and 104 to have a higher volumetric flow rate to increase power to the turbine than would be available without the augmenters.
The same conditions are created on the other side of the device hidden from this view to drive turbine 20. The circulating stream 70,71,72 converge at location 76,77,78 toward focus 52 and further reduce the backpressure downstream of the augmenter system for improved device performance. As moving stream 40 varies in velocity, governor augmentor 12 is able to swing on its hinge 26 since the drag force is proportional to stream velocity. During dangerous stream velocities governor augmenter 12 will swing up to a minimum attack angle and greatly reduce the overturning moment on the support structure as a means of protection. At sites where stream velocity is unsteady the varying attack angle of the governor augmenter 12 maintains a constant backpressure for improved turbine performance. The vertical orientation of the base and governor augmenters require no support for snow loading and reduce requirements of the support structure. The higher flow rate into the turbine system allows a higher revolutions per minute for the turbine and more efficient gearing to the turbine.
FIG. 5 shows a cut away view of nacelle 21 and rotational platform 29. On top of support structure 11 rotational platform 29 is able to rotate by means of a set of roller bearings 111 mounted on base plate 110. At least two others are provided to allow 29 to turn in any stream direction. Roller bearings 112 are also provided to resist overturning of nacelle 21. Flywheel 113 is mounted on turbine shaft 30 and protected inside the nacelle 21. Flywheel 113 has its circumference provided with bevel gear 113. Bevel gear 114 and generator shaft 115 transfer power from the turbine system to the transmission 116 and generator 117. The shaft 115 is held in position in raceway 119 by ball bearing 118 inside a journal. Nacelle 21 reduces maintenance on gears and generator. The device claimed is not limited by this one method of transferring power from turbine system to generator or pump shaft. The method indicated allows the turbine system to turn in any direction while the generator remains stationary. This eliminates a set of slip rings that would be required if the generator was also required to rotate.
|
A device and method of extracting energy from a moving stream such as an ocean current and the wind using a new and different augmenter system. Light weight augmenters are provided that circulate and focus portions of the moving stream to improve performance of a horizontal axis turbine system. Both turbine and augmenter systems are elevated above ground drag effects by a support structure. Means are provided to orient the device with changing stream direction and vary the augmenter system with changing stream velocity. Means are provided for conversion of the energy extracted from the moving stream to useful electrical or mechanical energy. Means are provided to protect the device and minimize maintenance.
| 8
|
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display device, a color filter substrate used therein and a color filter member.
A liquid crystal display device comprises two electrode substrates each having an alignment film and arranged such that the alignment films of the two substrates face each other and a liquid crystal layer arranged between the two substrates. The two electrode substrates are bonded to each other with a sealing member arranged in the peripheral region of the substrate and an end-sealing material. Also, a granular spacer or a spacer column made of a resin and formed by a photolithography method is arranged between the two substrates for keeping these two substrates a predetermined distance apart from each other. For allowing the liquid crystal display device to perform a color display, colored layers of red (R), green (G) and blue (B) are arranged on one of the substrates and, as desired, a transparent protective layer made of a resin is formed on the substrate having colored layers and a switching element mounted thereto.
In a liquid crystal display device of the particular construction, nonuniformity such as an image sticking and a display unevenness taking place after the durability (reliability) test are derived from the members in direct contact with the liquid crystal layer or the alignment film such as the sealing member, the end-sealing material, the spacer material, the protective layer and the colored layer.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to provide a liquid crystal display device that permits preventing the display unevenness, etc. derived from the members in direct contact with the liquid crystal layer or the alignment film.
Another object is to provide a member of a colored layer of a liquid crystal display device that permits preventing the display unevenness, etc. derived from the members in direct contact with the liquid crystal layer or the alignment film.
In the present invention, total amounts of an alkyl acid, phenyl carboxylic acid, a phenyl carboxylic acid derivative, phenylene dicarboxylic acid, a phenylene dicarboxylic acid derivative, an alkyl amine, aniline, an aniline derivative, phenylene diamine, a phenylene diamine derivative, phenyleneamine carboxylic acid, a phenyleneamine carboxylic acid derivative and an alkyl imide contained in or extracted from the sealing member, the end-sealing material, the spacer, the colored layer, etc. is controlled to fall within a predetermined range so as to prevent alignment unevenness and image sticking.
The alignment unevenness or image sticking is considered to take place by eluation into the liquid crystal or adsorption on the alignment film of organic impurities contained in the sealing member, the end-sealing material, the spacer material, the colored layer, etc. such as an alkyl acid, phenyl carboxylic acid, a phenyl carboxylic acid derivative, phenylene dicarboxylic acid, a phenylene dicarboxylic acid derivative, an alkyl amine, aniline, an aniline derivative, phenylene diamine, a phenylene diamine derivative, phenyleneamine carboxylic acid, a phenyleneamine carboxylic derivatives an alkyl imide, a phthalimide derivative, a cyano benzene derivative, and a dicyano benzene derivative, when the liquid crystal layer is held between the electrode substrates to assemble a liquid crystal display device. In other words, the alignment unevenness or image sticking is considered to take place in the case where the sealing member, the end-sealing material, the spacer material, the colored layer, etc. include a region that is brought into direct contact with the liquid crystal layer or the alignment film. It is considered reasonable to understand that the impurities contained in the sealing member, the end-sealing material, the spacer material, the colored layer, etc. permeate into the liquid crystal layer or the alignment film that are included in the display region so as to bring about eluation of these impurities into the liquid crystal layer and adsorption of these impurities on the alignment film so as to generate the alignment unevenness and image sticking. These impurities have been found to be contained in large amounts in, particularly, the green layer and the black layer included in the colored layers. Pigments G7 and G36 are generally used as parts of the green coloring material and the black coloring material of the color filter included in the liquid crystal display device. The impurities given above are contained in large amounts in these pigments. Further, impurities are contained in large amounts in the dispersant and polymer components used for dispersing these pigments into a colored paste. It is also conceivable that impurities are mixed unexpectedly in the resist preparation step in which the colored paste is mixed and dispersed. Further, the pigments and the dispersant are considered to be decomposed under high temperatures, by contact with an alkali or by exposure to an ultraviolet light, so as to generate the organic impurities noted above. Therefore, the green layer has been found to cause large amounts of impurities to be generated in the liquid crystal layer and the alignment film, compared with the red or blue layer. It is possible to suppress generation of the organic impurities by suitably refining the pigment and dispersant for preparation of a resist used for forming the green layer and by suitably selecting the materials used for the refining.
The present inventors have conducted a simple evaluation test in respect of the influences (particularly, image sticking) given to the display when various organic and inorganic substances are contained in a liquid crystal cell and when the materials used are refined. The experiment was conducted as follows.
Specifically, a TN liquid crystal cell was prepared by coating an alignment film on each of an array substrate having a switching element and a pixel electrode formed on a glass substrate and a counter substrate having a counter electrode formed on a glass substrate, followed by arranging these two substrates to permit the alignment films to face each other with a liquid crystal layer interposed therebetween. Two kinds of alignment film materials and two kinds of liquid crystal materials were used in the experiment, and the image sticking and display unevenness taking place after a durability (reliability) test were evaluated under the conditions that various organic and inorganic substances were attached to the alignment films. Table 1 shows the results.
TABLE 1
Display characteristics
Liquid crystal A
Liquid crystal B
nonuniform image
nonuniform image
sticking/nonuniform
sticking/nonuniform
Alignment
reliability (display
reliability (display
Attached substance
film
unevenness)
unevenness)
1
phthalic acid
P1
x/x
x/x
2
phthalic acid
P2
x/x
x/x
3
terephthalic acid
P1
x/x
x/x
4
terephthalic acid
P2
x/x
Δ/x
5
para-phthalic acid
P1
x/x
x/x
6
para-phthalic acid
P2
Δ/x
Δ/Δ
7
dichlorophthalic acid
P1
x/x
x/x
8
dichlorophthalic acid
P2
x/x
Δ/x
9
benzoic acid
P1
x/x
Δ/x
10
benzoic acid
P2
x/x
Δ/Δ
11
decanoic acid
P1
x/x
x/x
12
decanoic acid
P2
x/x
Δ/x
13
tetradecanoic acid
P1
x/x
x/x
14
tetradecanoic acid
P2
x/x
Δ/x
15
acetic acid
P1
x/x
Δ/x
16
acetic acid
P2
Δ/x
Δ/Δ
17
oxalic acid
P1
x/x
x/x
18
oxalic acid
P2
Δ/Δ
Δ/Δ
19
hexadecamine
P1
x/x
Δ/Δ
20
hexadecamine
P2
x/x
Δ/Δ
21
aniline
P1
x/x
Δ/Δ
22
aniline
P2
Δ/x
Δ/Δ
23
N-methyl aniline
P1
x/x
Δ/x
24
N-methyl aniline
P2
x/x
Δ/Δ
25
phthalic acid amide
P1
x/x
x/x
26
phthalic acid amide
P2
Δ/Δ
Δ/Δ
27
N-methylamino aniline
P1
x/x
x/x
28
N-methylamino aniline
P2
x/x
Δ/Δ
29
para-chlorobenzoic acid
P1
x/x
Δ/Δ
30
para-chlorobenzoic acid
P2
Δ/x
Δ/Δ
31
table salt
P1
◯/◯
◯/◯
32
hydrochloric acid
P2
◯/◯
◯/◯
33
calcium carbonate
P1
◯/◯
◯/◯
34
phthalic anhydride
P2
◯/◯
◯/◯
35
hexadecane
P1
◯/◯
◯/◯
36
toluene
P1
◯/◯
◯/◯
37
ethanol
P1
◯/◯
◯/◯
Notes:
Alignment film:
P1 . . . SE-5291 (trade name); P2 . . . Al-1051 (trade name)
Liquid Crystal:
A . . . ZLI-1565 (trade name); B . . . LIXON-5 (trade name)
x . . . occurrence of nonuniform image sticking/nonuniform reliability (display unevenness)
Δ . . . occurrence of slightly nonuniform image sticking/slightly nonuniform reliability (display unevenness)
◯ . . . no occurrence of nonuniform image sticking/nonuniform reliability (display unevenness)
A soluble polyimide SE-5291 manufactured by Nissan Chemical K. K. and a soluble polyimide A1-1051 manufactured by JSR K. K. were used for forming alignment films P1 and P2, respectively, shown in Table 1. Also, cyano series liquid crystal material ZLI-1565 manufactured by E. Merc Inc. and LIXON5001 manufactured by Chisso K. K. were used as liquid crystals A and B, respectively, shown in Table 1. For preparing the liquid crystal cell, an array substrate and a counter substrate were prepared first. Then, each of these substrates was coated with an alignment film material, followed by applying a heat treatment to the coating at 180° C. for 60 minutes and subsequently applying a rubbing treatment to the coating to prepare an alignment film. The alignment film thus prepared was partially coated with 1 μliter of an IPA (isopropyl alcohol) solution prepared by dissolving 10% by weight of the organic or inorganic substance shown in Table 1 as an attached material in IPA, followed by arranging the array substrate and the counter substrate to face each other with a liquid crystal layer interposed therebetween so as to assemble the liquid crystal cell. For evaluating the nonuniform image sticking, a checker pattern of the liquid crystal cell was kept imaged for 3 hours for evaluating the degree of nonuniform image sticking of the checker pattern in the vicinity of the coated region by the whole tone display pattern. Further, the liquid crystal cell was kept imaged for 100 hours at 50° C. and a relative humidity of 80% for evaluating the display unevenness, by a reliability test. Through these evaluation tests, the present inventors have found that the presence of specified organic substances within the liquid crystal cell brings about an image sticking and a display unevenness in the reliability test, as shown in Table 1. The specified organic substances noted above include an alkyl acid represented by formula (1), phenyl carboxylic acid or a phenyl carboxylic acid derivative represented by formula (2), phenylene dicarboxylic acid or a phenylene dicarboxylic acid derivative represented by formula (3), an alkyl amine represented by formula (4), aniline or an aniline derivative represented by formula (5), phenylene diamine or a phenylene diamine derivative represented by formula (6), phenyleneamine carboxylic acid or a phenyleneamine carboxylic acid derivative represented by formula (7), an alkyl imide represented by formula (8), a phthalimide derivative represented by formula (9), a cyano benzene derivative represented by formula (10), and a dicyano benzene derivative represented by formula (11):
R 1 COOH) n (1)
R 1 —NH 2 (4)
R 1 —NR 2 R 3 (8)
where R 1 is an alkyl group having 1 to 20 carbon atoms, R 2 is —H or an alkyl group having 1 to 20 carbon atoms, R 3 is an alkyl group having 1 to 20 carbon atoms, each of V, W, X, Y and Z is one selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, —F, —Cl, —Br, —C 6 H 5 and —H, and n is 1 or 2.
In the present invention, the impurity content represents the percentage by weight (% by weight) based on the total amount of the sealing member, the end-sealing material, the spacer material and the colored layer of the liquid crystal cell, i.e., the impurity content under the condition that these cell members of the liquid crystal cell were cured. On the other hand, the extraction amount represents a value when the cell members were assembled to form a liquid crystal cell, i.e., a value when the sealing member, the end-sealing material, the spacer material and the colored layer after curing were extracted into the liquid crystal. For extraction, the cured pieces of the cell members and the liquid crystal were put in an ampule tube and, after the ampule tube was sealed, stored for 100 hours at 80° C. for the analysis. The amounts of the cured pieces of the cell members were found to be 10 mm 3 for the colored layer, 2 mm 3 for the sealing member, 0.1 mm 3 for the spacer material, and 0.05 mm 3 for the end-sealing material. The amount of the liquid crystal was 50 cc. A fluorine-contained liquid crystal and a cyano-contained nematic liquid crystal can be used as a liquid crystal material for the extraction. Specifically, used were a cyano-contained liquid crystal of ZLI-1565 manufactured by E. Merc Inc. and a fluorine-contained liquid crystal of LOXON50001 manufactured by Chisso K. K. It is possible to use “Shimazu 14A” (trade name of a gas chromatography analytical apparatus manufactured by Shimazu Seisakusho K. K.) or “Shimazu 10AS” (trade name of a liquid chromatography analytical apparatus manufactured by Shimazu Seisakusho K. K.) as a measuring apparatus. A gas chromatography analytical apparatus was used this time.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention.
FIG. 1 is a vertical cross sectional view showing a liquid crystal display device according to one embodiment of the present invention;
FIG. 2 is a vertical cross sectional view showing an array substrate included in the liquid crystal display device according to the embodiment of the present invention;
FIG. 3 is a vertical cross sectional view showing a liquid crystal display device according to another embodiment of the present invention; and
FIG. 4 is a plan view schematically showing the coating positions of the sealing member and the end-sealing material included in the liquid crystal display device of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
A liquid crystal display device according to a first embodiment of the present invention will now be described with reference to FIGS. 1 and 2.
FIG. 1 schematically shows a liquid crystal display device of the present invention and schematically illustrates the color filter substrate included in the liquid crystal display device shown in FIG. 2 .
As shown in FIG. 1, a liquid crystal display device 10 includes a counter substrate 120 , a color filter substrate 110 , and a liquid crystal layer 70 held between the substrates 120 and 110 . These two substrates are held apart from each other by, for example, a granular spacer 31 . As shown in FIG. 4, the counter substrate 120 and the color filter substrate 110 are bonded to each other by a sealing member 25 arranged to surround the outer peripheries of these substrates except a liquid crystal filling port 32 . Also, the liquid crystal filling port 32 is sealed with an end-sealing material 33 . ZLI-1565 manufactured by E. Merc Inc. was used as the liquid crystal material. Also, a thermosetting epoxy series adhesive ES-5500 manufactured by Mitsui Toatsu Kagaku K. K. was used as the sealing material.
The counter substrate 120 includes a transparent substrate 21 , a transparent electrode 22 made of ITO and formed on the substrate 21 , and an alignment film 13 formed on the electrode 22 .
As shown in FIG. 2, the array substrate includes a transparent substrate 11 . A scanning line (not shown) made of MoW (molybdenum·tungsten) and a gate electrode 16 are formed on the transparent substrate 11 . A gate insulating film 12 made of silicon oxide or silicon nitride is arranged to cover the scanning line and the gate electrode 16 . A semiconductor layer 15 made of amorphous silicon or the like is formed on the gate insulating film 12 . Further, a source electrode 20 , a drain electrode 18 and a signal line (not shown) each having a three-layer structure of Mo/Al/Mo are also formed on the gate insulating film 12 . The signal line and the scanning line are arranged to cross each other. A switching element 14 consisting of the gate electrode 16 , the gate insulating film 12 , the semiconductor layer 15 , the source electrode 20 and the drain electrode 18 and a pixel electrode 30 connected to the switching element 14 are arranged at each cross point between the signal line and the scanning line. Further, a red (R) colored layer 24 a , a green (G) colored layer 24 b and a blue (B) colored layer 24 c are arranged to cover the switching element 14 and to form a stripe on the entire substrate surface. The pixel electrode 30 , which is positioned on the colored layer 24 , is connected to the source electrode 20 via a contact hole 26 formed in the colored layer 24 . Further, an alignment film 13 is formed on the entire substrate surface to cover the pixel electrode 30 and the colored layer 24 . The colored layer portions were formed of CG-2000, CR-2000 and CB-2000 (trade names of ultraviolet light curing type acrylic resins manufactured by Fuji Hunt Technology K. K.) and the alignment film was formed of AL-1051 (trade name of polyimide manufactured by JSR K. K.).
The manufacturing process of the liquid crystal display device of this embodiment and the relationship between the amount of the impurities contained in the colored layer and the display characteristics will now be described.
The manufacturing process of the color filter substrate 110 will be described first. In the first step, the gate electrode 16 and the scanning line were formed by depositing a molybdenum·tungsten film in a thickness of about 0.3 μm by a sputtering method on the transparent substrate 11 , followed by pattering the deposited film. Then, an amorphous silicon film was deposited by a CVD method, followed by patterning the deposited film to form the semiconductor layer 15 of TFT. Further, Mo, Al and Mo were deposited successively, followed by patterning the deposited films to form the signal line, the source electrode 20 and the drain electrode 18 .
In the next step, the substrate surface having the electrodes formed thereon was coated with an ultraviolet light curing type acrylic red resist solution CR-2000 by a spin coating method. The coating was pre-baked for about 5 minutes at about 90° C., followed by exposing the pre-baked coating to an ultraviolet light having an intensity of 150 mJ/cm 2 through a predetermined mask pattern. The photo mask pattern used in this step included a stripe pattern corresponding to the red colored layer and a circular pattern having a diameter of 15 μm corresponding to the contact hole 26 for connecting the pixel electrode 30 to the source electrode 20 . Then, development was performed for about 60 minutes by using an aqueous solution containing about 0.1% by weight of TMAH (tetramethylammonium hydride), followed by water wash and, then, post-baking for about one hour at about 200° C. so as to form the red colored layer 24a including the contact hole 26 .
Then, the green colored layer 24 b and the blue colored layer 24 c were formed similarly.
Further, indium tin oxide (ITO) was deposited on the colored layer 24 by a sputtering method, followed by patterning the resultant ITO layer to form the pixel electrode 30 . Then, the entire surface of the substrate was coated with polyimide used as a material of the alignment film, followed by applying an alignment treatment to the polyimide coating to form the alignment film so as to obtain the color filter substrate 110 .
In the next step, ITO was deposited in a thickness of about 100 nm by a sputtering method on the transparent substrate 21 to prepare the counter electrode 22 . Then, the entire surface of the substrate was coated with polyimide used as a material of the alignment film, followed by applying an alignment treatment to the polyimide coating to form the alignment film so as to prepare the counter substrate 120 .
Granular spacer particles 31 each having a diameter of about 5 μm were dispersed on the alignment film of the counter substrate 120 at a rate of about 100 particles per square millimeter. Then, the outer peripheral portion of the counter substrate 120 was coated with the sealing member 25 having fibers of a predetermined size mixed therein except the liquid crystal filling port. The counter substrate 120 of the particular condition was bonded to the color filter substrate 110 using the sealing member 25 so as to form a vacant cell.
Finally, a nematic liquid crystal material having a chiral material added thereto was introduced under vacuum into the cell through the liquid crystal filling port. After the filling, the filling port was sealed with an ultraviolet light curing resin used as the end-sealing material 33 , followed by arranging polarizing plates on both sides of the cell so as to form the liquid crystal display device.
The present inventors have found through the trial manufacture that the impurities contained in the sealing material, the end-sealing material, the spacer material and the colored layer are eluded into the liquid crystal or adsorbed on the alignment film so as to bring about the display unevenness and nonuniform image sticking and that the display unevenness and the nonuniform image sticking can be prevented by regulating the impurity content. The specific impurities were already described herein under the heading “Brief Summary of the Invention”.
Tables 2 to 5 show experimental data covering the cases where various impurities were added to the liquid crystal cell included in the liquid crystal display device described above. The total impurity content shown in the Tables denotes the percentage by weight of the impurities based on the sum in weight of the sealing member, the end-sealing material, the spacer material and the colored layer. Also, the total extraction amount of the impurities denotes the extraction amount in the case where the cell members were assembled into a liquid crystal cell.
Table 2 shows the experimental data on the display characteristics covering the case where aniline used as an impurity was added to the sealing member in various amounts.
TABLE 2
Total extraction
amount of
Total
impurities when
Display characteristics
Added
Addition
impurity
extracted with
Poor display
Poor display
impurity
amount
content
liquid crystal
(image sticking)
(poor reliability)
aniline
0%
1%
20 ppm
none
none
aniline
2%
4%
70 ppm
none
none
aniline
5%
6%
110 ppm
slight image
display unevenness
sticking occurred
occurred
aniline
10%
11%
200 ppm
severe image
display unevenness
sticking occurred
severely occurred
Table 3 shows the experimental data on the display characteristics covering the vase where phthalic acid used as an impurity was added to the sealing member in various amounts.
TABLE 3
Total extraction
amount of
Total
impurities when
Display characteristics
Added
Addition
impurity
extracted with
Poor display
Poor display
impurity
amount
content
liquid crystal
(image sticking)
(poor reliability)
phthalic acid
0%
1%
20 ppm
none
none
phthalic acid
2%
4%
80 ppm
none
none
phthalic acid
5%
6%
150 ppm
slightly occurred
poor display
around filling port
occurred around
filling port
phthalic acid
10%
11%
320 ppm
slightly occurred
poor display
around filling
severely occurred
port
around filling port
Table 4 shows the experimental data on the display characteristics, covering the case where the spacer of the liquid crystal cell was prepared by patterning a black resin CK-2000 in place of using the granular spacer, and benzoic acid used as an impurity was added to the spacer material in varied amounts.
TABLE 4
Total impurity
Total extraction
Impurity
content of
amount of
Addition
content
colored layer
impurities when
Display characteristics
Added
amount to
under
under cured
extracted with
Poor display
Poor display
impurity
resist
resist state
state
liquid crystal
(image sticking)
(poor reliability)
benzoic acid
0%
0.05%
1%
40 ppm
none
none
benzoic acid
0.05%
0.10%
2%
90 ppm
none
none
benzoic acid
0.5%
0.55%
4%
160 ppm
none
slight
occurrence of
poor display
benzoic acid
2%
2.05%
11%
250 ppm
slight
occurrence of
occurrence
poor display
Table 5 shows the experimental data on the display characteristics, covering the case where decanoic acid used as an impurity was added to the resist for the red colored layer in varied amounts.
TABLE 5
Total impurity
Total extraction
Impurity
content of
amount of
Addition
content
colored layer
impurities when
Display characteristics
Added
amount to
under
under cured
extracted with
Poor display
Poor display
impurity
resist
resist state
state
liquid crystal
(image sticking)
(poor reliability)
decanoic acid
0%
0.01%
1%
20 ppm
none
none
decanoic acid
0.05%
0.06%
2%
100 ppm
none
none
decanoic acid
0.5%
0.501%
4%
180 ppm
slight occurrence
none
decanoic acid
2%
2.01%
11%
260 ppm
occurred
none
Table 6 shows the experimental data on the display characteristics, covering the case where used was resist having the impurity content reduced by using a refined resist for the green colored layer as well as a refined pigment and a refined dispersant.
TABLE 6
Total extraction
amount of
Addition
Total
impurities when
Display characteristics
amount to
impurity
extracted with
Poor display
Poor display
resist
content
liquid crystal
(image sticking)
(poor reliability)
resist for green
0.3%
8%
500 ppm
occurred
poor display
colored layer not
occurred
using refining material
resist for green
0.01%
2%
50 ppm
none
none
colored layer
using refining material
FIG. 3 shows a second embodiment of the present invention. In the first embodiment, the switching element is of reverse staggered type in which an amorphous silicon is used as a semiconductor layer. In the second embodiment, however, the switching element is of a forward staggered type in which a polycrystalline silicon is used as a semiconductor layer. Also, a columnar spacer is used in the second embodiment, though a spherical spacer is used in the first embodiment. In the second embodiment, a black resin having red, green and blue pigments mixed therein is used for forming the spacer.
As shown in FIG. 3, a liquid crystal display device 10 of the second embodiment comprises a counter substrate 120 , an array substrate 310 , a liquid crystal layer 70 held between the counter substrate 120 and the array substrate 310 , and a columnar spacer 230 for keeping these two substrates a predetermined distance apart from each other. The counter substrate 120 includes a glass substrate 21 , a counter electrode 22 formed on the glass substrate 21 , and an alignment film 13 formed on the counter electrode 22 . On the other hand, the array substrate 310 includes a glass substrate 210 , an undercoating layer 211 of a double-layer structure consisting of a silicon oxide film and a silicon nitride film and formed on the glass substrate 210 , a semiconductor active layer 214 (channel region) and high impurity regions 213 forming source and drain regions, said active layer 214 and high impurity regions 213 being formed on the undercoating layer 211 , a gate oxide film 212 formed to cover the active layer 214 and the high impurity regions 213 , and a gate electrode 215 formed on the gate oxide film 212 , thereby forming a polycrystalline silicon TFT of a forward staggered type. Incidentally, the scanning line (not shown) is formed in the step of forming the gate electrode 215 . A signal line 219 of a double-layer structure consisting of a Mo layer and an Al layer is formed on the scanning line and the gate insulating film 212 . The signal line 219 is connected to the high impurity regions 213 via a first contact hole 221 extending through an interlayer insulating film 220 and the gate insulating film 212 . An inorganic insulating film 216 of a double-layer structure consisting of a silicon oxide film and a silicon nitride film and a colored layer 217 made of an organic resin, having a thickness of 3 μm, and in the shape of a stripe of red, blue and green colors are formed on the signal line 219 . A second contact hole 222 is formed through the inorganic insulating film 216 and the colored layer 217 . The columnar spacer 230 is formed on that region of the colored layer 217 in which a pixel electrode is not formed in the subsequent step to keep the array substrate 310 and the counter substrate 120 a predetermined distance apart from each other. A pixel electrode 218 consisting of ITO (Indium Tin Oxide) is formed on the colored layer 217 so as to be electrically connected to the signal line 219 . Further, the alignment film 13 is formed to cover the spacer 230 , the pixel electrode 218 and the colored layer 217 . The columnar spacer 230 is formed of a black colored layer, i.e., a layer of CK-2000 (trade name of an ultraviolet light curing type acrylic resin consisting of an organic resin and red, green and blue pigments contained in the organic resin and manufactured by Fuji Hunt Technology K. K.). In forming the columnar spacer 230 , a light shielding layer was formed simultaneously along the outer periphery of the substrate.
The amounts of impurities when the colored layer and the spacer are extracted in the liquid crystal material and the impurity content of the colored layer and the spacer after formed are defined in the second embodiment, too, making it possible to obtain a liquid crystal display device exhibiting good display characteristics.
As described above, the impurities have been found to be contained in large amounts in, particularly, the green layer among the three colored layers, supporting that it is effective to define the impurity content of, particularly, the green layer among the colored layers. It has also been found that, in the case of using a black resin, i.e., resin containing red, green and blue pigments, it is effective to decrease the impurity content of the black resin because the black resin contains a green pigment.
The particular effect of the present invention can also be obtained in the case where the technical idea of the present invention is applied to a liquid crystal display device constructed such that a color filter is arranged on the counter substrate positioned to face the array substrate and the counter electrode is formed on the color filter. In a liquid crystal display device of the particular construction, a lead-out electrode or the like is patterned in the step of forming the counter electrode, and the display device includes a region in which the liquid crystal layer is in contact with the colored layer directly or with an alignment film interposed therebetween. It is effective to decrease the impurity content of the colored layer as in the present invention in the display device of the particular construction, too. Also, when it comes to a liquid crystal display device in which an opening is formed in the counter electrode to partially control the generated electric field so as to control the direction of alignment of the liquid crystal molecules, the technical idea of the present invention produces a prominent effect because the liquid crystal layer is in contact with the colored layer directly or with the alignment film interposed therebetween.
As described above, the impurity content of an organic resin film that is in contact with the liquid crystal layer directly or with a film that is likely to permit permeation of impurities such as an alignment film interposed therebetween is decreased in the present invention so as to obtain a liquid crystal display device capable of preventing an image sticking and achieving a good display performance.
It should be noted that the amounts of the impurities contained in the colored layer, the sealing member and the spacer material are defined in the present invention so as to prevent nonuniform image sticking and the display unevenness taking place after the durability (reliability) test.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
|
Disclosed is a liquid crystal display device, comprising two substrates each having an alignment film, a sealing member arranged in the outer peripheries of the two substrates to permit the outer peripheries of these two substrates, which are arranged such that the alignment films of these two substrates face each other, to be bonded to each other except a liquid crystal filling port, a spacer for keeping the two substrates a predetermined distance apart from each other, a liquid crystal layer formed by filling a liquid crystal material through the liquid crystal filling port into the clearance between the two substrates, and an end-sealing material for sealing the liquid crystal filling port, wherein total amounts of an alkyl acid, phenyl carboxylic acid or a phenyl carboxylic acid derivative, phenylene dicarboxylic acid or a phenylene dicarboxylic acid derivative, an alkyl amine, aniline or an aniline derivative, phenylene diamine or a phenylene diamine derivative, phenyleneamine carboxylic acid or a phenyleneamine carboxylic acid derivative, an alkyl imide, a phthalimide derivative, a cyano benzene derivative, and a dicyano benzene derivative contained in the sealing member, the end-sealing material and the spacer is not larger than 3%.
| 8
|
BACKGROUND OF THE INVENTION
Ice fishing is a popular sport in areas where fresh water lakes freeze over in the winter. Ice is safe to walk on when it reaches 4 or 5 inches in thickness, and in colder climates the ice may reach a depth of 3 feet or more. The fishing is conducted through a hole drilled in the ice ranging from 5 inches to 13 inches in diameter which is cut by either a manually operated or a motorized ice auger. Ice augers powered by a power unit having a gasoline engine are currently popular and are available from many manufacturers.
When a fish is hooked under the ice, it must be pulled up through the hole and, while that is not a problem with smaller fish, many large fish are lost when they must be turned to come up into the hole through which the fishing line extends. The vertical sidewall surface of the hole forms a 90° angle with the bottom of the ice so on most occasions the fish on the hook must make a 90° turn to enter the bottom of the hole. Many large fish are lost at this point because of the extra stress placed on the fishing line and hook when extra pressure is applied to the line to pull the fish around the corner and, in some cases, a sharp edge formed at the bottom of the hole may even cut the line.
SUMMARY OF THE INVENTION
We have discovered that the loss of fish for the reason outlined above can be largely eliminated by enlarging the opening in the ice at the water surface by cutting away the ice around the bottom edge of the hole to form a larger opening with a beveled sidewall gradually diverging away from the vertical walls of the original hole. The enlarged opening, which may extend upwardly from the bottom of the hole six inches or so, still has a circular cross-section but has a truncated, triangular shape in vertical section. If the resulting angle between the surface of the enlarged hole and the bottom of the ice is increased to about 135°, for example, much less effort is required to pull the fish around that corner, thus reducing the likelihood that the line will break or the hook will break loose.
To cut this enlarged opening, we have designed an instrument that can be attached to the power unit of the ice auger. The cutting instrument includes an elongated shaft having an adjustable cutting edge mounted at its bottom end. The instrument is attached to the power unit and lowered into the hole far enough so the cutting edge is below the bottom of the ice. At that time, the cutting edge is extended outwardly by a control linkage to a desired position at an angle with the vertical, at which point the power unit is started, the power is increased and upward pressure is applied causing the cutting edge to engage the ice at the bottom of the hole and gradually cut the larger opening.
These and other features of the invention will be described more fully in the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view in side elevation of the ice auger attachment attached to a power unit, shown positioned in a hole in the ice, the ice being shown in section;
FIG. 2 is a fragmentary, enlarged view in side elevation of the instrument, with portions being shown in section, and with the cutting edge shown in a resting position; and
FIG. 3 is a view similar to that shown in FIG. 2, with the cutting edge shown in an operative position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, wherein like elements of the invention are identified by like numerals, an ice auger attachment 10 is shown attached to a power unit 11. In FIG. 1, attachment 10 is positioned in a hole 12 drilled in the ice 13. When originally drilled, hole 12 has a circular cross-section and extends vertically through the ice so that the inner surface of the hole 12 forms a 90° angle with the top surface of the ice 13 and also with the bottom surface of the ice 13, as shown in dash lines at the bottom.
A control shaft 14, which in the preferred embodiment is a one inch steel pipe, 48 inches long, is attached at its upper end to the power unit 11 and extends vertically through the hole 12 at its center. Control shaft 14 at its top end 14a has a metal ring 15 welded thereto to form a stop against which the drive socket 11a of the power unit rests. Near its bottom end 14b, an L-shaped stop member 16 is attached by welding or the like to extend perpendicular to the control shaft 14.
A first spacing device, comprising a circular disk 17, having a central opening with a band clamp 18 attached at one end to the disk around the opening, is positioned on control shaft 14 with the shaft extending through clamp 18 and the center opening in disk 17. Disk 17 is clamped to shaft 14 at a location spaced from bottom end 14b so that it will be positioned within the central area of opening 12 in ice 13 to assist in centering and stabilizing the ice auger attachment 10 in the hole 12.
A second spacing device, comprising a circular disk 20 having a central opening through which shaft 14 extends is permanently welded to the shaft at the central opening at a selected position between disk 17 and stop member 16. Disk 20 preferably has the same diameter as disk 17 to again engage the sidewalls of the hole 12 to provide additional stability. Disk 20 is positioned in a horizontal plane in hole 12 and is provided with an upwardly extending rim member 21 on its upper surface adjacent its edge to strengthen the disk and to provide an enlarged surface area for engaging the ice opposite the cutting blade.
Attached to the bottom surface of plate 20 and extending radially outwardly from shaft 14 are a pair of spaced support bracket members 22, 23 which extend to a position near the edge of disk 20 and are provided at their outer ends with aligned openings through which a pivot pin 23b extends. An L-shaped member 24 having a control arm portion 24a connected to a support portion 24b at a pivot point is pivotally mounted to support bracket members 22, 23 at pivot pin 23b. Control arm portion 24a extends toward shaft 14 and support portion 24b extends outwardly and downwardly, generally toward stop member 16. As shown in FIGS. 2 and 3, L-shaped member 24 can be pivoted from a position with support portion 24b parallel to shaft 14 and engaging or resting against stop member 16 to a position outwardly therefrom forming an angle with shaft 14, as shown in FIG. 3. As best shown in FIG. 2, support bracket members 22, 23 and stop member 16 are about the same length and are constructed and arranged so that when the support portion 24b of L-shaped member 24 is resting against stop member 16, it is located within a diameter smaller than the diameter of hole 12 so that the ice auger attachment 10 can be easily inserted into the hole.
A control linkage extends along the shaft to permit an operator to move the L-shaped member between its two positions. The control linkage includes a control rod 27, which in the preferred embodiment is a 3/8 inch steel rod, 36 inches long, extending along shaft 14 through openings in disks 17 and 20 and pivotally connected at one end to a link 28 pivotally connected at its other end to the free end of control arm portion 24a. The upper portion of control rod 27 is held in position and guided by a U-shaped metal bracket 14c welded at its ends to shaft 14. Control rod 27 is also provided at its upper end with an elongated generally U-shaped handle 27a welded at its ends to rod 27. The upper end 27b of rod 27 is bent at a 90° angle and is, thus, shaped to have that end portion engageable with a selected one of a plurality of openings or holes 30, 30a in shaft 14. End portion 27b can be inserted into one of the openings 30, 30a to prevent axial movement of control rod 27 with respect to shaft 14. A collar member 31 is moveable on shaft 14 between ring 15 and handle 27a, and has an inner diameter such that when placed over rod 27 as shown in FIG. 1 it will hold end portion 27b in a selected one of the openings 30, 30a in shaft 14.
A cutting blade 32 is mounted on support portion 24b and has a cutting edge facing away from support portion 24b and shaft 14. In the preferred embodiment, the cutting edge is approximately 10 inches in length and the cutting blade is made of 1/8 by 11/2 inch cold roll steel material having a plurality of bolts welded thereto which extend through openings in control arm portion 24b so that threaded nuts can be used to attach cutting blade 32 to L-shaped member 24. The cutting blade can thus be easily removed to permit sharpening or replacement of the blade. The mounting bolt holes for the cutting blade are positioned so that the cutting blade can be turned (rotated end for end). The reason for this change is that one manufacturer's power unit turns in one direction and another manufacturer's unit may turn in the opposite direction. The rotation of the cutting blade allows the cutting edge to engage the ice for either clockwise or counter-clockwise rotation of individual power units.
In the embodiment shown, control shaft 14 has two openings 30, 30a. Axial movement of control rod 27 from its engagement with opening 30a as shown in FIG. 2, to its engagement with opening 30 as shown in FIG. 3, causes the link 28 to push control arm portion 24a downwardly and, thus, rotate L-shaped member 24 to swing support portion 24b outwardly to the position shown in FIG. 3 so that a line extending through support portion 24b to intersect control shaft 14 would form an angle of approximately 45° therewith. With the apparatus locked in the position shown in FIG. 3, the entire unit can be pulled upwardly. With the power unit 11 operating, the entire ice auger attachment 10 will rotate rapidly to, thus, rotate cutting blade 32 around an axis formed by shaft 14 to engage the ice around the bottom edge of the hole and gradually cut it away to form a larger opening at the bottom end of opening 12 with sides diverging downwardly and outwardly away from the walls of the original opening to form an enlarged opening with a generally truncated, triangular shaped vertical cross-section, as shown in FIG. 1. With the cutting blade positioned as shown, the angle between the new sidewall portion 12a cut by the blade and the bottom surface 13a of the ice 13 is approximately 135°. After the opening has been formed, the control rod 27 is, again, moved upwardly to return the cutting blade to the position shown in FIG. 2, at which point the unit can be removed from the opening.
The above specification, examples and data provide a complete description of the structure and use of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.
|
An ice cutting instrument for beveling the ice around the bottom of a hole cut in the ice on a lake, which is driven by a motorized power unit. A vertical power shaft supports a cutting blade which can be adjusted between a position near the shaft to an angled position by a control rod extending along the shaft. The shaft carries one or more spacing devices to center it in the hole. The instrument is inserted in the hole, the blade is extended, and the power unit is then energized to rotate the instrument, which is then pulled upwardly to cut the enlarged opening.
| 4
|
FIELD OF THE INVENTION
The present invention relates to a semiconductor field, and more particularly to a method for preventing auto-doping effect on substrate having heavily-doped region during epitaxial growth.
BACKGROUND OF THE INVENTION
Epitaxial technology where heavily arsenic (As)-doped semiconductor acts as substrate has been increasingly widely used in device fabrication, and especially in diode, triode, VDMOS, varactor diode, IGBT and etc. With the miniaturization and the increase of integration level of devices, the consistency of epitaxial wafer having heavily As-doped silicon substrate and the transition region width of epitaxial layer are crucial for the performance and reliability of devices.
During chemical vapor epitaxy, the impurity of As is unavoidable between the epitaxial layer and the heavily-doped region of substrate and between the epitaxial layer and the undoped region of substrate. Take the example of the growth of intrinsic epitaxial layer on silicon wafer having heavily-doped region, wherein an impurity distribution vertical to heavily-doped region is named as vertical auto doping (as the direction indicated by AA′ in FIG. 1 ) and an impurity distribution not vertical to heavily-doped region is named as horizontal auto doping (as the direction indicated by BB′ in FIG. 1 ), wherein the impurity vertical diffusion mainly comprises two parts of 1. solid thermal diffusion at the interface between the epitaxial layer and the heavily-doped substrate and 2. auto-doping of the impurity ion absorbed by the substrate surface or the impurity gas in the background atmosphere into the epitaxial layer during epitaxial growth, and wherein horizontal auto doping effect is mainly caused by the second phenomenon.
Conventional silicon wafer epitaxial process of heavily As-doped substrate mainly utilizes the process of so-called “two-step epitaxy”, wherein key steps are as follow: 1. loading the substrate in the reaction chamber with the temperature increased to 1000-1200° C. before the hydrogen chloride (HCl) is introduced to clean the substrate surface and the inner wall of the reaction chamber; 2. introducing a large amount of hydrogen (H2) to clean the inner wall of the reaction chamber and the substrate so as to remove the impurity absorbed on the substrate surface and in the reaction chamber; 3. growing an intrinsic epitaxial layer to prevent further out-diffusion of impurities from the substrate; 4. re-introducing a large amount of H2 into the reaction chamber to clean the inner wall of the reaction chamber and the substrate so as to remove impurities absorbed on the substrate surface and in the reaction chamber; and 5. performing a second stage growth until a desired thickness of the epitaxial layer is reached. Conventional process of “two-step epitaxy” has the advantage of minimizing the vertical diffusion effect for thick epitaxial layer growth, and the disadvantages of 1. poor inhibition of vertical auto doping effect for thin epitaxial layer growth; and 2. no obvious inhibition of horizontal auto doping effect. Auto-doping effect of As for epitaxial film formed by conventional chemical vapor deposition is as shown in FIG. 2 .
Therefore, it is a technical problem for urgent solution to prevent vertical and horizontal diffusion of atoms heavily doped and reduce the doping concentration for epitaxial layer in undoped region during the epitaxial layer growth on substrate having heavily-doped region.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method of epitaxial layer growth preventing vertical and horizontal diffusion of auto-doping atoms so as to ensure the performance and enhance the reliability of the devices in peripheral circuit region.
In order to solve the above technical problems, the invention adopts the following technical schemes:
Technical Scheme 1:
This technical scheme provides a method of epitaxial growth effectively preventing auto-doping effect, comprising the steps of:
1) Preparing a semiconductor substrate having heavily-doped buried layer and removing surface oxide from said semiconductor substrate;
2) Cleaning the reaction chamber to be used so as to remove dopant atoms and other impurities absorbed on the inner wall of the reaction chamber;
3) Loading said semiconductor substrate into the cleaned reaction chamber and pre-baking said semiconductor substrate under vacuum conditions so as to remove moisture and oxide from the surface of said semiconductor substrate before the extraction of dopant atoms desorbed from the surface of said semiconductor substrate;
4) Under high temperature and low gas flow conditions, growing a first intrinsic epitaxial layer on the surface of said semiconductor substrate where the dopant atoms have been extracted out; and
5) Under low temperature and high gas flow conditions, growing a second epitaxial layer of required thickness on the structural surface of the first intrinsic epitaxial layer formed previously.
Preferably, the dopant used in the heavily-doped buried layer region of said semiconductor substrate is one of arsenic, phosphorus, tellurium and boron; said heavily-doped buried layer region is prepared by ion implantation or solid thermal diffusion; said semiconductor substrate can be silicon or other semiconductor materials such as germanium.
Preferably, in said step 2), the reaction chamber can be cleaned by HCl gas under conditions of a temperature of 1190° C., a flow of 20 sccm, a carrier gas of nitrogen (N2) or H2, and a duration of 30 seconds.
Preferably, said first and second intrinsic epitaxial layers are formed at a low pressure of less than 100 Torr.
Preferably, dichlorosilane is used as source gas for the growth of the first and second intrinsic epitaxial layers, wherein a low growth rate can be achieved by controlling the flow of dichlorosilane gas and the carrier gas of hydrogen.
Preferably, the growth method used for said first and second intrinsic epitaxial layers is chemical vapor epitaxy or molecular beam epitaxy.
Preferably, said first intrinsic epitaxial layer is grown with a thickness between 10 and 200 nm, wherein growth conditions are a temperature in the range of 1100° C. to 1250° C., a dichlorosilane flow in the range of 50 sccm to 400 sccm, and a hydrogen flow in the range of 5 slm to 80 slm.
Preferably, said second epitaxial layer is grown under conditions of a temperature in the range of 900° C. to 1250° C., and a dichlorosilane flow in the range of 100 sccm to 800 sccm.
Preferably, said second epitaxial layer is undoped layer, P type doped layer, or N type doped layer, wherein dopant atoms for said P type doped layer can be boron and dopant atoms for said N type doped layer can be phosphorus or arsenic.
Preferably, said pre-baking conditions in step 3) are a temperature in the range of 1000° C. to 1250° C., a duration of 20 seconds to 10 minutes, and an atmosphere of inert gas.
Preferably, said inert gas is hydrogen or nitrogen.
The epitaxial growth method in foregoing technical scheme 1 is more suitable for use when the area of the heavily-doped buried layer region is less than 50% of the surface area of the semiconductor substrate.
Technical Scheme 2:
This technical scheme provides a method of epitaxial growth effectively preventing auto-doping effect with an additional step, based on the technical scheme 1, of partial etch of the first intrinsic epitaxial layer to reduce the thickness of said first intrinsic epitaxial layer and remove the surface dopant atoms thereon.
Preferably, HCl gas can be introduced into said reaction chamber to etch said first intrinsic epitaxial layer.
Preferably, conditions of etching the first intrinsic epitaxial layer are a temperature in the range of 1100° C. to 1200° C. and a pressure of less than 40 Torr.
Preferably, the method of epitaxial growth in this technical scheme can be used when the area of the heavily-doped buried layer region of said semiconductor substrate is greater than half of the surface area of said semiconductor substrate.
Technical Scheme 3:
This technical scheme provides a method of epitaxial growth effectively preventing auto-doping effect, wherein the pre-baking step in technical scheme 1 is replaced by a step of etching the surface of said semiconductor substrate; that is to say, under vacuum and high temperature conditions, gas is introduced to clean the surface of said semiconductor substrate so as to etch away dopant atoms absorbed on said semiconductor substrate surface and extract them out of the reaction chamber.
Preferably, said vacuum and high temperature conditions are a temperature of 1200° C., a pressure of about 20 Torr and a duration of 30 seconds.
The invention has the advantages that:
(1) said “pre-baking” process in the method of epitaxial growth in the invention can effectively prevent horizontal auto-doping effect;
(2) the growth of intrinsic epitaxial layer adopts an epitaxial method of low pressure, high temperature, low gas (DCS) flow and low deposition rate, wherein the process conditions of this step are also crucial to prevent horizontal auto-doping effect;
(3) HCl is adopted to etch back the first thin intrinsic epitaxial layer and thus reduce horizontal auto-doping effect;
(4) before the semiconductor substrate is loaded in the reaction chamber, HCl gas is used under high temperature to clean dopant atoms absorbed by the inner wall of the reaction chamber, which greatly reduce the possibility of auto-doping of impurity gas of the background atmosphere into the epitaxial layer during the epitaxial growth; and
(5) process conditions for the growth of ultra thin epitaxial layer (0.2˜0.6 microns) are provided.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the structure of silicon wafer having heavily-doped region.
FIG. 2 is a schematic view of arsenic auto-doping in an epitaxial film formed by conventional chemical vapor deposition.
FIG. 3 is a flowchart of a method of epitaxial growth effectively preventing auto-doping effect according to the present invention.
FIG. 4 is a temperature graph adopted by each step in method of epitaxial growth effectively preventing auto-doping effect according to the present invention.
FIG. 5 is a schematic view showing the relationship between pre-baking time and horizontal auto-doping effect of arsenic in the method of epitaxial growth effectively preventing auto-doping effect according to the present invention.
FIG. 6 is a schematic view showing the relationship between deposition time and hydrogen flow of the first intrinsic epitaxial layer and horizontal auto-doping effect of arsenic in the method of epitaxial growth effectively preventing auto-doping effect according to the present invention.
FIG. 7 is a schematic view of the auto-doping effect of arsenic of the epitaxial film deposited by the method of epitaxial growth effectively preventing auto-doping effect according to the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
The technical schemes of the embodiments of the present invention are described below in a detailed and complete manner with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. Without creative effort, all other embodiments to be acquired by an ordinary person skilled in the art on the basis of the embodiments of the present invention belong to the protection scope of the present invention.
In order to further clarify the object, technical schemes and advantages of the invention, the method of epitaxial growth effectively preventing auto-doping effect of the invention is described in detail below with reference to the accompanying drawings. It shall be noted that the following description of each embodiment is based on that arsenic is used as the dopant in the heavily-doped buried layer region of the semiconductor substrate; however, a person skilled in the art shall understand that the dopants in the heavily-doped buried layer region are not limited to arsenic, but include other materials such as phosphorus, tellurium and boron, and that semiconductor substrate materials include but are not limited to silicon as well.
Embodiment 1
Please refer to FIG. 3 . The method of epitaxial growth effectively preventing auto-doping effect of this embodiment comprises the following steps:
Firstly, form a silicon wafer substrate having heavily-doped buried layer region by As ion implantation, wherein the depth of said buried layer is 0.4 μm and the heavy doping concentration of said buried layer is 8E19 atoms/cm3.
Next, HF acid solution is used to remove the surface oxide from said silicon wafer substrate.
Next, before said silicon wafer substrate is loaded in the reaction chamber, introduce HCl gas into the reaction chamber to clean the reaction chamber under atmospheric pressure and high temperature (as the temperature graph shown in FIG. 4 ) so as to remove dopant atoms and other impurities absorbed on the inner wall of the reaction chamber, wherein preferred conditions are a temperature of 1190° C., a HCl flow of about 20 sccm, a carrier gas of N2 or H2, and a duration of 30 seconds.
Next, cool the reaction chamber to a low temperature (e.g., of about 850° C.) before load in said silicon wafer substrate having heavily-doped buried layer region.
Next, under vacuum and high temperature conditions, pre-bake said silicon wafer substrate so as to remove moisture and oxide caused by exposure to air from the surface of said silicon wafer substrate. The dopant atoms of As absorbed on the surface of silicon wafer substrate are much easier to be desorbed under high temperature before said desorbed As atoms are extracted out of the reaction chamber under low vacuum conditions, which in turn better the prevention of the horizontal auto doping of As. Preferred pre-baking conditions are a temperature of 1150° C., a pressure of about 20 Torr (1 Torr=1/760 atm=1 mmHg=133.322 Pa), a hydrogen flow of 60 slm, and a duration of 20 seconds.
Next, a first thin intrinsic epitaxial layer is grown under conditions of a high temperature (e.g., 1150° C.), a low pressure (e.g., of about 20 Torr), and a low DCS gas flow (e.g., of about 122 sccm) wherein a preferred thickness is about 100 nm and a duration is 20 seconds. On one hand, the process conditions of high temperature enable the dopant atoms absorbed on the surface of the heavily-doped buried layer region to be desorbed and extracted out of the reaction chamber, and, on the other hand, the process conditions of high temperature and low deposition rate facilitate the improvement of the crystal lattice structure of the epitaxial layer ready to be formed and reduce the absorption of the dopant atoms on the freshly formed surface of the epitaxial layer.
Lastly, a main silicon epitaxial layer of required thickness is grown under conditions of a low temperature (of 1000° C.), a low pressure (of 70 Torr), and a high DCS gas flow (of 400 sccm) so as to form a required epitaxial layer structure, wherein a typical epitaxial layer thickness is 0.3 μm, 0.4 μm, 0.6 μm, 0.8 μm and etc.
The epitaxial films prepared by the method of epitaxial growth adopted in this embodiment and by the prior methods have the same structure, as shown in FIG. 1 ; however, in this embodiment, wherein temperatures employed for each step is as shown in FIG. 4 , if the pre-baking time is prolonged, the As concentration of the interface between the epitaxial layer and the undoped substrate will decrease with the increase of the pre-baking time; that is to say, the horizontal auto-doping effect of As is further inhibited when the pre-baking time increases, specifically as shown in FIG. 5 . FIG. 6 is the schematic view showing the relationship between the horizontal auto-doping effect of As and the deposition time and hydrogen flow of the first intrinsic epitaxial layer, and, as shown in this figure, no matter increasing the growth temperature of the first intrinsic epitaxial layer or reducing the deposition rate by increasing the carrier gas flow, the As concentration of the interface between the epitaxial layer and the substrate that is not heavily doped is greatly reduced. Also, as shown in FIG. 7 , both the vertical and horizontal auto doping effects of As atoms are effectively prevented, wherein the impurity concentrations of As in the epitaxial layers of both heavily-doped and undoped silicon wafer substrates are around 1E15 atoms/cm3, which are far below the impurity concentration in the epitaxial layer formed by conventional epitaxial growth process (as shown in FIG. 2 ).
As can be seen from the above, the method of epitaxial growth on silicon wafer substrate adopted in this embodiment effectively prevents the vertical and horizontal auto-doping effect of arsenic atoms caused by heavily-doping buried layer region, which is of significant importance for the use of diode array of low resistance buried layer and the application of high-speed BiCMOS, IGBT and other devices. During the process, dopant atoms absorbed on the surface of the silicon wafer substrate are desorbed and extracted out of the reaction chamber by pre-baking under high temperature and low pressure conditions, the first intrinsic epitaxial layer is grown at low deposition rate (high temperature, low pressure and low gas flow) to improve the crystal lattice quality of the epitaxial layer and cover the heavily-doped buried layer so as to prevent the horizontal auto doping of dopant atoms, and the main epitaxial layer (i.e., the second epitaxial layer) is grown under low temperature, low pressure and high gas flow conditions, characterized by high deposition rate, low temperature and the reduction of the diffusion of dopant atoms in the buried layer.
Embodiment 2
The method of epitaxial growth effectively preventing auto-doping effect of this embodiment comprises the following steps:
Step 1: form a silicon wafer substrate having heavily-doped buried layer by solid thermal diffusion of heavily As-doped silicon glass, wherein said buried layer has a depth of 0.5 microns and the heavy doping concentration of said buried layer is 3E19 atoms/cm3.
Step 2: remove the surface oxide from the silicon wafer substrate with HF acid solution.
Step 3: before said silicon wafer substrate is loaded in the reaction chamber, introduce HCl gas into the reaction chamber to clean the reaction chamber under atmospheric pressure and high temperature so as to remove dopant atoms and other impurities absorbed on the inner wall of the reaction chamber, wherein a typical temperature is 1190° C., a HCl flow is about 20 sccm, a carrier gas is N2 or H2, and a duration is 30 seconds.
Step 4: cool the reaction chamber to a low temperature (e.g., of about 850° C.) before load in said silicon wafer substrate.
Step 5: under vacuum and high temperature conditions, pre-bake said silicon wafer substrate under conditions of a temperature of 1150° C., a pressure of about 20 Torr and a duration of 20 seconds.
Step 6: a first thin intrinsic epitaxial layer is grown under conditions of a high temperature (e.g., 1150° C.), a low pressure (e.g., of about 20 Torr), and a low DCS gas flow (e.g., of about 122 sccm), wherein a preferred thickness is about 100 nm and a duration is 20 seconds.
Step 7: a silicon epitaxial layer of required thickness is grown under conditions of a low temperature (e.g., of 1000° C.), a low pressure (e.g., of 70 Torr), and a high DCS gas flow (e.g., of 400 sccm) so as to form a required epitaxial layer structure, wherein a typical epitaxial layer thickness is 0.3 μm, 0.4 μm, 0.6 μm, and etc.
This embodiment has the advantage that the buried layer is formed by solid thermal diffusion of heavily As-doped silicon glass, which provides a simpler process.
Embodiment 3
The method of epitaxial growth effectively preventing auto-doping effect of this embodiment comprises the following steps:
Firstly, form a silicon wafer substrate having heavily-doped buried layer by As ion implantation or by solid thermal diffusion of heavily As-doped silicon glass.
Next, remove the surface oxide from the silicon wafer substrate with HF acid solution.
Next, before said silicon wafer substrate is loaded in the reaction chamber, introduce HCl gas into the reaction chamber to remove, under atmospheric pressure and high temperature, dopant atoms and other impurities absorbed on the inner wall of the reaction chamber, wherein a typical temperature is 1190° C., a HCl flow is about 20 sccm, a carrier gas is N2 or H2, and a duration is 30 seconds.
Next, cool the reaction chamber to a low temperature (e.g., of about 850° C.) before load in said silicon wafer substrate.
Next, under vacuum conditions, pre-bake said silicon wafer substrate under conditions of a temperature of 1150° C., a pressure of about 20 Torr and a duration of 20 seconds.
Next, a first thin intrinsic epitaxial layer is grown under conditions of a high temperature (of 1150° C.), a low pressure (of about 20 Torr), and a low DCS gas flow (of about 122 sccm), wherein a preferred thickness is about 20 nm and a duration is 40 seconds.
Next, under conditions of a high temperature (of 1150° C.) and a low pressure (of about 20 Torr), HCl gas is introduced to etch the surface of said first thin intrinsic epitaxial layer so as to remove partial thickness thereof and dopant atoms absorbed on the surface of the epitaxial layer, wherein said etch thickness is less than or equal to the thickness of the first epitaxial layer.
Lastly, a second epitaxial layer (e.g., a P type doped layer or a N type doped layer) of required thickness is grown under conditions of a low temperature (of 1000° C.), a low pressure (of 70 Torr), and a high DCS gas flow (of 400 sccm) so as to form a required epitaxial layer structure, wherein a typical epitaxial layer thickness is 0.3 μm, 0.4 μm, 0.6 μm, 0.8 μm and etc.
This embodiment has the advantage that, upon the growth of the first intrinsic epitaxial layer, HCl gas is used to etch the surface thereof under high temperature and low pressure conditions to remove partial thickness thereof and dopant atoms absorbed on the surface of the epitaxial layer, and therefore prevent the auto-doping effect of dopant atoms. This embodiment is more suitable for the epitaxial growth of silicon wafer substrate where the area of the heavily-doped buried layer region is large (normally when the area of the heavily-doped region is more than 50% of the surface area of the silicon wafer substrate).
Embodiment 4
The method of epitaxial growth effectively preventing the auto-doping effect of arsenic of this embodiment comprises the following steps:
Firstly, form a silicon wafer substrate having heavily-doped buried layer by As ion implantation or by solid thermal diffusion of heavily As-doped silicon glass, wherein said buried layer has a depth of 0.3 microns and the doping concentration of said buried layer is 3E19 atoms/cm3.
Next, remove the surface oxide from said silicon wafer substrate with HF acid solution.
Next, before said silicon wafer substrate is loaded in the reaction chamber, introduce HCl gas into the reaction chamber to clean the reaction chamber under atmospheric pressure and high temperature so as to remove dopant atoms and other impurities absorbed on the inner wall of the reaction chamber, wherein a typical temperature is 1190° C., a HCl flow is about 20 sccm, a carrier gas is N2 or H2, and a duration is 30 seconds.
Next, cool the reaction chamber to a low temperature (e.g., of about 850° C.) before load in said silicon wafer substrate.
Next, under vacuum and high temperature conditions, introduce HCl gas to clean the surface of said silicon wafer substrate so as to etch away dopant atoms absorbed on the surface of the silicon wafer substrate and extract them out of the reaction chamber, wherein a temperature is 1200° C., a pressure is about 20 Torr and a duration is 30 seconds during the etch process.
Next, a first thin intrinsic epitaxial layer is grown under conditions of a high temperature (of 1150° C.), a low pressure (of about 20 Torr), and a low DCS gas flow (of about 122 sccm), wherein a typical thickness is 20 nm and a duration is 40 seconds.
Lastly, a silicon epitaxial layer of required thickness is grown under conditions of a low temperature (of 1000° C.), a low pressure (of 70 Torr), and a high DCS gas flow (of 400 sccm) so as to form a required epitaxial layer structure, wherein a typical epitaxial layer thickness is 0.3 μm, 0.4 μm, 0.6 μm, 0.8 μm and etc.
This embodiment is different from foregoing embodiments in that pre-baking is replaced by the introduction of HCl gas into the reaction chamber to etch the semiconductor substrate surface and remove the surface dopant atoms thereof and therefore prevent the auto-doping effect of dopant atoms.
To sum up, the present invention provides a method of epitaxial growth effectively preventing vertical and horizontal auto-doping effect, wherein a semiconductor substrate is subject to a process of pre-baking or etch at first, then an intrinsic layer is formed under high temperature and low gas flow conditions, and next a main epitaxial layer is grown under low temperature and high gas flow conditions. As a result, the auto-doping effect of arsenic atoms is effectively prevented and a relatively thin epitaxial layer is obtained. This method is suitable not only to the fabrication of the driving diode of phase change memory, but also to the fabrication of other electronic devices, and, in particular, of high application value to the fabrication of triode, high-speed BiCMOS and so on.
|
An epitaxial growth method for preventing auto-doping effect is presented. This method starts with the removal of impurities from the semiconductor substrate and the reaction chamber to be used. Then the semiconductor substrate is loaded in the cleaned reaction chamber to be pre-baked under vacuum conditions before the extraction of the dopant atoms desorbed from the surface of the semiconductor substrate. Next, under high temperature and low gas flow conditions, a first intrinsic epitaxial layer is formed on the surface of said semiconductor substrate. Following this, under low temperature and high gas flow conditions, a second epitaxial layer of required thickness is formed on the structural surface of the grown intrinsic epitaxial layer. Last, silicon wafer is unloaded after cooling. This method can prevent auto-doping effect during the epitaxial growth on semiconductor substrate and thus ensure the performance and enhance the reliability of the devices in peripheral circuit region.
| 7
|
FIELD OF THE INVENTION
[0001] The invention relates to an external breast prosthesis, and in particular to a breast prosthesis that can be reshaped or customized to the individual user.
BACKGROUND OF THE INVENTION
[0002] External breast prostheses are artificial breast forms that can be worn after a surgery or other treatment in which the breast has been altered or removed. For example, external breast prostheses are available for women who have had a mastectomy or lumpectomy to remove breast cancer, and to those who have uneven or unequal sized breasts resulting from radiation, reconstruction procedures or birth defects.
[0003] Currently, most prosthetic breasts consist of a polyurethane film outer skin filled with a soft silicone, foamed silicone gel, or some other type of silicone elastomer usually containing any number of filler materials, herein referred to as silicone. The form is set in a particular shape as the silicone vulcanizes. This shape is permanent and is determined by the shape of the mold used to manufacture the part. The silicone is soft and relatively lightweight but does not provide any drape or movement that would be expected from an actual human breast. Prosthetic breasts presently on the market are also filled with such soft silicone materials mixed together with glass micro spheres to lighten the weight of the prosthesis.
[0004] Generally, silicone gel has become the most widely accepted material used in external breast prostheses, for the most part for its resilient properties. A prime example of this style of external breast prosthesis is disclosed in U.S. Pat. No. 4,019,209 issued to Spence. However, in the ensuing years, it became apparent that the weight of the gel is such that it produces undo strain on the mastectomy patient's back, resulting in side effects ranging from discomfort to painful back injuries. As a result, significant effort has been undertaken to develop lighter weight breast prostheses without losing the look, feel and behavior of a natural breast. One such improvement is disclosed in U.S. Pat. No. 4,380,569 issued to Shaw. As illustrated in FIG. 3, the external breast prosthesis includes an elastic covering layer 24 enclosing a silicone gel core 20 containing glass microspheres 22 with a back piece 26. Although this product provided lighter weight breast prostheses, it was at the expense of the natural look, feel and behavior of a natural breast. Another breast prosthesis designed to be light-weight but not at the expense of the natural look, feel and behavior is disclosed in U.S. Pat. No. 6,066,220 issued to Schneider-Nieskens. As illustrated in FIG. 1, Schneider-Nieskens developed an external breast prosthesis having an inner core 2 housed within cover layers 3 and 4. The cover layers are each comprised of two foils 5, 6, 7 and 8 made of thermoplastic polyurethane between which is a layer of standard silicone gel. The inner core 2 is enclosed within the cover layers and consists of a silicone compound mixed with lightweight fillers such as micro glass spheres.
[0005] Further efforts in the design an even lighter external breast prosthesis are disclosed in U.S. Pat. No. 5,902,335 and U.S. Published Application No. 2007/0293945. These type of breast prostheses included dual chambers, i.e., an outer chamber filled with regular silicone gel mixed with glass microspheres to reduce weight, and an inner chamber filled with just regular silicone gel.
[0006] It is noted that all of the above discussed breast prostheses are made of silicone gel. As previously discussed the silicone assumes the shape of the mold that it was formed in, and further shaping is not possible. Since no two women have the same residual tissue configuration, it is not ideal to have a breast form of the exact same shape for everyone. The use of silicone gel in the currently known products presents a limitation in developing an extremely lightweight breast prosthesis that retains the look, feel, and behavior of a natural breast.
[0007] Furthermore, lightweight silicone sometimes referred to as foamed or whipped silicone is very costly to produce. The manufacturers which use this material often must have it imported from Europe where the majority of it is manufactured. Or the breast forms themselves are made overseas where the silicone is supplied. Lead times and costs of the filler material can be considerable.
[0008] In light of the limitations of the currently known breast prostheses, there exists a tremendous need not only for an extremely lightweight breast prosthesis, but also one less expensive and one capable of being reconfigured or reshaped to be customized to the individual user. Applicant's invention, as discussed in greater detail hereinbelow, provides a solution to such drawbacks.
BRIEF SUMMARY OF THE INVENTION
[0009] In view of the foregoing, it is an object of the present invention to provide an external breast prosthesis that is extremely lightweight.
[0010] It is another object of the present invention to provide an external breast prosthesis that is capable of being reconfigured or reshaped to be customized to the individual user.
[0011] It is another object of the present invention to provide an external breast prosthesis that is less expensive than other prior art breast prostheses.
[0012] It is another object of the present invention to provide an external breast prosthesis that is more exact to the natural breasts of the user.
[0013] It is another object of the present invention to provide an external breast prosthesis that closely mimics the natural feel of a natural breast.
[0014] It is another object of the present invention to provide an external breast prosthesis that closely mimics the natural behavior of a natural breast.
[0015] It is another object of the present invention to provide an external breast prosthesis that is comfortable to wear and will minimize strain on a user's spine.
[0016] To accomplish the above objectives, the external breast prosthesis of the present invention uses a polyurethane film outer skin filled with a different type of gel filler which consists of a mixture of white mineral oil, hydrogenated styrenic block copolymer, and glass micro spheres (for weight reduction). The combination of these ingredients will be referred to as copolymer gel filler from here forward. The copolymer gel filler provides a much more realistic feel than the silicone gel filler. In addition the drape and rheological properties are more consistent with natural human tissue.
[0017] The copolymer gel filler is a thermoplastic elastomer that can be reshaped with the application of heat. The breast prosthesis of the present invention could provide a considerable advantage over silicone gel filled breast prostheses with respect to customization. It is highly desirable to have a breast form that conforms to the shape of the residual tissue, both for quality of appearance and more importantly comfort. The tissue of a post operative chest cavity is highly sensitive for a considerable amount of time following the surgery so any addition to comfort level could greatly increase quality of life for the patient.
[0018] The copolymer gel filler used in the present invention is mostly comprised of mineral oil which is an abundant commodity. Thus, the cost of processing the copolymer gel filler of the present invention is considerable less that the cost of any silicone gel filler available. Also, the copolymer gel of the present invention has a density of 0.87 gram/cubic centimeter, which is considerably lower than silicone at 0.99 grams/cubic centimeter. These are densities before any filler or glass bubbles are added.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 illustrates a perspective view of the external breast prosthesis of the present invention.
[0020] FIG. 2 illustrates a cross-sectional view of the external breast prosthesis of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Referring to FIG. 1 , a perspective view of the lightweight breast prosthesis (1) of the present invention is illustrated. Although the perspective view is taken from a side angle, the breast prosthesis is symmetrical about its central axis affording its use to either the left or right chest of the user.
[0022] Referring to FIG. 2 , a cross-sectional view of the breast prosthesis of the present invention is illustrated. The breast prosthesis includes front skin ( 2 ) and rear skin ( 3 ) comprised of polyurethane films and initially formed to approximate the shape of a natural breast by any conventional molding technique. The front skin ( 2 ) is secured at its peripheral edge to the peripheral edge to rear skin ( 3 ) such as by an adhesive or by any conventional heat sealing technique. The front skin also has nipple ( 5 ) formed therein during the molding process. Contained within the front and rear skins is a copolymer gel filler ( 7 ). The copolymer gel filler consists of a mixture of white mineral oil, hydrogenated styrenic block copolymer comprised of a SEPS type: polystyrene-b-poly(ethylene/propylene)-b-polystyrene, of a SEPS type: polystyrene-b-poly(ethylene/butylene)-b-polystyrene, of a SEEPS type: polystyrene-b-poly(ethylene-ethylene/propylene)-b-polystyrene, or a mixture of any of the above copolymers, and glass micro spheres. As illustrated in FIG. 2 , the glass microspheres ( 4 ) are added mainly to reduce the weight of the copolymer. In the preferred embodiment, the mixture consists of approximately 89% Kaydol® oil, 3.5% Septon® 2006 SEPS, 0.2% Septon® 4033 SEEPS, and 7.3% glass micro spheres. However, this ratio is not concrete and could consist of 80% to 93% mineral oil, 2% to 12% copolymer, and 0% to 15% glass micro spheres depending on the desired feel of the final product. Also, although in the preferred embodiment, the block copolymer consists of Septon® 2006 or 4033, although others may be used.
[0023] Other types of block copolymers may include a triblock copolymer or combinations thereof, such as a hydrogenated poly(styrene-b-isoprene), a hydrogenated poly(styrene-b-isoprene-b-styrene), a hydrogenated poly(styrene-b-butadiene-b-styrene), a hydrogenated poly(styrene-b-isoprene/butadiene-b-styrene), or combinations thereof. Also, a polystyrene-b-poly(ethylene/propylene) (SEP), polystyrene-b-poly(ethylene/propylene)-b-polystyrene (SEPS), polystyrene-b-poly(ethylene/butylene)-b-polystyrene (SEBS), or polystyrene-b-poly(ethylene-ethylene/propylene)-b-polystyrene (SEEPS), or combinations thereof may be used. Some of such polymers are sold, for example, under the trademarks SEPTON® or KRATON®.
[0024] Kraton® D SBS (http://www.kraton.com/Products/Kraton_D_SBS/) The Kraton D SBS family of polymers is versatile with a combination of high strength, wide range of hardness, and low viscosity for easy thermoplastic melt processing or processing in solution. The SBS block copolymers are composed of blocks of styrene and butadiene. It is the material of choice for footwear and the modification of bitumen/asphalt. It is also very useful in pressure sensitive adhesives, hot melt spray diaper adhesives, construction adhesives, impact modification of styrenics, thermoformed clear rigid packaging, and compounds.
[0025] Kraton® D SIS (http://www.kraton.com/Products/Kraton_D_SIS/) The Kraton D SIS family of polymers are high performance thermoplastic elastomers with a combination of high strength, low hardness and low viscosity for easy thermoplastic processing as a melt or in solution. SIS polymers are based on styrene and isoprene and are the lowest hardness and lowest viscosity of all the styrenic block copolymers. They are ideally suited for formulating pressure sensitive adhesives (packaging tape, labels, etc.), hot melt spray diaper adhesives, elastic films, and many other innovative applications.
[0026] Kraton® FG (http://www.kraton.com/Products/Kraton_FG/) Kraton FG polymers are SEBS polymers with maleic anhydride (MA) grafted onto the rubber midblock. The commercial Kraton FG polymers have 1.0 to 1.7 wt. % MA grafted onto the block copolymer. The MA grafting improves the adhesion to nylon, polyester, ethylene vinyl alcohol, aluminum, steel, glass, and many other substrates. The FG polymers are very efficient impact modifiers in nylon and polyesters for making super tough engineering thermoplastic materials.
[0027] Developmental Products
[0028] (http://www.kraton.com/Products/Developmental_Products/)
[0029] Kraton Polymers is committed to continuous innovation and subsequently is frequently introducing new polymers. These polymers are being specifically designed for new applications and new property sets that cannot be achieved with existing commercial block copolymers.
[0030] The Kraton® A polymer series are hydrogenated block copolymers which have styrene copolymerized with ethylene/butylene in the midblock (S-(EB/S)-S).
[0031] The Kraton® S polymer series are unsaturated block copolymers that have isoprene and butadiene copolymerized in the midblock (S-(I/B)-S).
[0032] The Kraton® ERS polymers have an enhanced ethylene/butylene rubber midblock which is more compatible with polypropylene.
[0033] In addition to Kaydol® oil, other plasticizers particularly preferred for use in practicing the present invention are well known in the art, they include rubber processing oils such as paraffinic and naphthenic petroleum oils, highly refined aromatic-free paraffinic and naphthenic food and technical grade white petroleum mineral oils, and synthetic liquid oligomers of polybutene, polypropene, polyterpene, etc. The synthetic series process oils are high viscosity oligomers which are permanently fluid liquid nonolefins, isoparaffins or paraffins of moderate to high molecular weight.”
[0034] The high viscosity triblock and branched copolymers: SEEPS, SEBS, SEPS, (SEB).sub.n, and (SEP).sub.n can be measured under varying conditions of weight percent solution concentrations in toluene. The most preferred and useful triblock and branched copolymers selected have Brookfield Viscosity values ranging from about 1,800 cps to about 80,000 cps and higher when measured at 20 weight percent solution in toluene at 25.degree. C., about 4,000 cps to about 40,000 cps and higher when measured at 25 weight percent solids solution in toluene. Typical examples of Brookfield Viscosity values for branched copolymers (SEB).sub.n and (SEP).sub.n at 25 weight percent solids solution in toluene at 25.degree. C. can range from about 3,500 cps to about 30,000 cps and higher; more typically, about 9,000 cps and higher. Other preferred and acceptable triblock and branched copolymers can exhibit viscosities (as measured with a Brookfield model RVT viscometer at 25.degree. C.) at 10 weight percent solution in toluene of about 400 cps and higher and at 15 weight percent solution in toluene of about 5,600 cps and higher. Other acceptable triblock and branched copolymers can exhibit about 8,000 to about 20,000 cps at 20 weight percent solids solution in toluene at 25.degree. C. Examples of most preferred high viscosity triblock and branched copolymers can have Brookfield viscosities at 5 weight percent solution in toluene at 30.degree. C. of from about 40 to about 50 cps and higher. While less preferred polymers can have a solution viscosity at 10 weight percent solution in toluene at 30.degree. C. of about 59 cps and higher.
[0035] The high viscosity triblock, radial, star-shaped, and multi-arm copolymers of the invention can have a broad range of styrene end block to ethylene and butylene center block ratio of about 20:80 or less to about 40:60 or higher. Examples of high viscosity triblock copolymers that can be utilized to achieve one or more of the novel properties of the present invention are styrene-ethylene-butylene-styrene block copolymers (SEBS) available from Shell Chemical Company and Pecten Chemical Company (divisions of Shell Oil Company) under trade designations Kraton G 1651, Kraton G 1654X, Kraton G 4600, Kraton G 4609 and the like. Shell Technical Bulletin SC:1393-92 gives solution viscosity as measured with a Brookfield model RVT viscometer at 25.degree. C. for Kraton G 1654X at 10% weight in toluene of approximately 400 cps and at 15% weight in toluene of approximately 5,600 cps. Shell publication SC:68-79 gives solution viscosity at 25.degree. C. for Kraton G 1651 at 20 weight percent in toluene of approximately 2,000 cps. When measured at 5 weight percent solution in toluene at 30.degree. C., the solution viscosity of Kraton G 1651 is about 40. Examples of high viscosity SEBS triblock copolymers includes Kuraray's SEBS 8006 which exhibits a solution viscosity at 5 weight percent at 30.degree. C. of about 51 cps. Kuraray's 4055 SEEPS (styrene-ethylene/ethylene-propylene-styrene) block polymer made from hydrogenated styrene isoprene/butadiene block copolymer or more specifically made from hydrogenated styrene block polymer with 2-methyl-1,3-butadiene and 1,3-butadiene which exhibits a viscosity at 5 weight percent solution in toluene at 30.degree. C. of about 90 mPa-S, at 10 weight percent about 5800 mPa-S. Kuraray's 2006 SEPS polymer exhibits a viscosity at 20 weight percent solution in toluene at 30.degree. C. of about 78,000 cps, at 5 weight percent of about 27 mPa-S, at 10 weight percent of about 1220 mPa-S, and at 20 weight percent 78,000 cps. Kuraray SEPS 2005 polymer exhibits a viscosity at 5 weight percent solution in toluene at 30.degree. C. of about 28 mPa-S, at 10 weight percent of about 1200 mPa-S, and at 20 weight percent 76,000 cps. Other grades of SEBS, SEPS, (SEB).sub.n, (SEP).sub.n polymers can also be utilized in the present invention provided such polymers exhibits the required high viscosity. Such SEBS polymers include (high viscosity) Kraton G 1855X which has a Specific Gravity of 0.92, Brookfield Viscosity of a 25 weight percent solids solution in toluene at 25.degree. C. of about 40,000 cps or about 8,000 to about 20,000 cps at a 20 weight percent solids solution in toluene at 25.degree. C.
[0036] The styrene to ethylene and butylene (S:EB) weight ratios for the Shell designated polymers can have a low range of 20:80 or less. Although the typical ratio values for Kraton G 1651, 4600, and 4609 are approximately about 33:67 and for Kraton G 1855X approximately about 27:73, Kraton G 1654X (a lower molecular weight version of Kraton G 1651 with somewhat lower physical properties such as lower solution and melt viscosity) is approximately about 31:69, these ratios can vary broadly from the typical product specification values. In the case of Kuraray's SEBS polymer 8006 the S:EB weight ratio is about 35:65. In the case of Kuraray's 2005, 2006, and 4055 the and S:EEP weight ratios are 20, 35 and 30 respectively. Much like S:EB ratios of SEBS and (SEB).sub.n, the S:EP ratios of very high viscosity SEPS, (SEP).sub.n copolymers are expected to be about the same and can vary broadly. The S:EB, S:EP weight ratios of high viscosity SEBS, SEPS, (SEB).sub.n, and (SEP).sub.n useful in forming the gel compositions of the invention can range from lower than about 20:80 to above about 40:60 and higher. More specifically, the values can be 19:81, 20:80, 21:79, 22:78, 23:77, 24:76, 25:75, 26:74, 27:73, 28:72, 29:71, 30:70, 31:69, 32:68, 33:67, 34:66, 35:65, 36:64, 37:63, 38:62, 39:61, 40:60, 41:59, 42:58, 43:57, 44:65, 45:55, 46:54, 47:53, 48:52, 49:51, 50:50, 51:49 and etc. Other ratio values of less than 19:81 or higher than 51:49 are also possible. Broadly, the styrene block to elastomeric block ratio of the high viscosity triblock, radial, star-shaped, and multi-arm copolymers of the invention is about 20:80 to about 40:60 or higher, less broadly about 31:69 to about 40:60, preferably about 32:68 to about 38:62, more preferably about 32:68 to about 36:64, particularly more preferably about 32:68 to about 34:66, especially more preferably about 33:67 to about 36:64, and most preferably about 33:67. In accordance with the present invention, triblock copolymers such as Kraton G 1654X having ratios of 31:69 or higher can be used and do exhibit about the same physical properties in many respects to Kraton G 1651 while Kraton G 1654X with ratios below 31:69 may also be use, but they are less preferred due to their decrease in the desirable properties of the final gel.
[0037] Other polymers and copolymers (in major or minor amounts) can be selectively melt blended with one or more of the high viscosity polymers as mentioned above without substantially decreasing the desired properties; these (III) polymers include (SBS) styrene-butadiene-styrene block copolymers, (SIS) styrene-isoprene-styrene block copolymers, (low styrene content SEBS) styrene-ethylene-butylene-styrene block copolymers, (SEP) styrene-ethylene-propylene block copolymers, (SEPS) styrene-ethylene-propylene-styrene block copolymers, (SB).sub.n styrene-butadiene and (SEB).sub.n, (SEBS).sub.n, (SEP).sub.n, (SI).sub.n styrene-isoprene multi-arm, branched or star-shaped copolymers and the like. Still, other (III) polymers include homopolymers which can be utilized in minor amounts; these include: polystyrene, polybutylene, polyethylene, polypropylene and the like.”
[0038] Applicant has discovered that the copolymer gel filler of the present invention provides a much more realistic feel than the silicone gel filler of the prior art prostheses. Furthermore, in using the gel copolymer filler, the drape and rheological properties of the present invention are more consistent with natural human tissue.
[0039] Referring again to FIG. 2 , adhered to the rear skin ( 3 ) of the breast prosthesis is a lightweight fabric ( 6 ) made of polyester and Lycra®. Alternatively, Nylon® could also be employed. The fabric may be printed with a logo and an attractive pattern if desired. The fabric ( 6 ) serves several purposes. First of all, it serves as an aesthetic enhancement, and as a means to remove moisture from perspiration through wicking. The fabric also provides a structure to the rear surface of the breast prosthesis that serves to hold the shape of the form. The fabric could be adhered to the rear skin by any conventional technique, preferably a thermal bonding process.
[0040] The uniqueness of the breast prosthesis of the present invention is that its copolymer gel filler is a thermoplastic elastomer that can be reconfigured or reshaped by subjecting the prosthesis to heating, followed by reshaping, and then allowing the prosthesis to cool until it retains the new shape. The breast prosthesis can be heated by any conventional source that would not be detrimental to the overall structure. Such sources would include a conventional hair dryer, submersion into a pool of hot water, or any type of oven set to an appropriate temperature. The copolymer gel filled breast prosthesis is a considerable advantage over silicone gel filled breast prostheses with respect to customization. As discussed earlier, the silicone gel filled breast prostheses of the prior art are thermosetting and cannot be reshaped once they have been vulcanized. It is highly desirable to have a breast form that conforms to the shape of the residual tissue or to a natural breast formation, both for quality of appearance and more importantly comfort. The tissue of a post operative chest cavity is highly sensitive for a considerable amount of time following the surgery so any addition to comfort level could greatly increase quality of life for the patient.
[0041] Since the copolymer gel filler of the present invention is mostly comprised of mineral oil which is an abundant commodity and much cheaper than silicone, the cost of manufacturing the breast prosthesis of the present invention is drastically reduced.
|
An external lightweight breast prosthesis comprising an elastomeric polyurethane skin filled with copolymer gel filler comprising a mixture of mineral oil, thermoplastic copolymer and glass microspheres and initially configured to approximate the shape of a natural breast wherein the breast prosthesis can be reconfigured to be customized to the individual wearer by subjecting the prosthesis to heating, reshaping, and followed by cooling until the prosthesis retains its new shape.
| 0
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. application Ser. No. 339,419, filed Jan. 15, 1982, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a preparation for conditioning and grooming the hair.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a preparation which conditions and grooms the hair. This preparation is simple and economical to make and easy and agreeable to use.
The excellent grooming and conditioning action of the preparation according to the invention can largely be attributed to the following findings. Sebum and dandruff deposits are removed as a result of the high proportion of phosphatides (lecithins of a vegetable and animal origin, kephalins), which are solvents for hydrophobic substances. There is in particular an in-depth action on the hair follicles. Cholesterol deposited on the cellular membranes and which blocks cellular metabolism is emulsified and transported away. This can stimulate follicle cellular metabolism.
Preferably, nutrients and build-up substances are simultaneously supplied to the follicle cells representing the growth of the hair in order to assist this process. These substances include phosphatidic acids which aid permeable membrane transport, inositols which exercise a growth function under certain conditions and cytochromes serving as catalysts on the final respiratory path. These are catalysts on the final oxidation path and bring about electron transfer between flavin enzymes and molecular oxygen. The last enzyme in the cytochrome series is cytochrome oxidase, which directly reacts with oxygen and catalyzes the oxidation of cytochrome C. By change of valency (electron valency change) copper participates in this reaction, in addition to heme iron. The activity of cytochrome oxidase is limited by lipids. According to the present invention there must be a combination of at least two of the following components in the hair preparation:
(1) Vegetable lecithins,
(2) Cytochromes, particularly cytochrome oxidase,
(3) Phosphatidyl inositols,
(4) Phosphatides, and
(5) Phosphatidic acids, particularly free phosphatidic acids.
Advantageously the preparation according to the invention contains all five substances. Although in actual fact, lecithins should be placed with the phosphatides they are indicated separately here (cf. component (1) or (4)), because components (1) and (2) to (5) are separated from one another, while taking into account the preparation process. From the chemical standpoint the most important phosphatides are kephalins and lecithins in which the base colamine or choline appears.
Advantageously component (1), i.e. vegetable lecithins are prepared by extraction from the tonic 3N lecithin of VEB Arzneimittelwerke Dresden or Buer lecithin obtained from soya beans.
Component (2), i.e. cytochromes, is the enzyme group of cellular hemins, whose biochemical function is based on the transfer of electrons, as stated hereinbefore. However, for reasons of completeness reference is made to Beyer, Lehrbuch der organischen Chemie, S. Hirzel-Verlag, Leipzig 1968, p. 743 ff.
Of particular importance for the purpose of the present invention is the process for preparing the hair conditioner and grooming agent, which is characterized by 16 different stages, as recited in claim 14, including the preparation of an animal heart, particularly a bovine or cattle heart for isolating components or active substances (2) to (5), which are then combined with component (1) in stages (15) and (16).
The hair conditioner and grooming agent according to the invention can be used in different forms, e.g., as a solution, emulsion or dispersion. The conditioner and grooming agent should be applied substantially externally, but internal application is not excluded. It is known that in the case of epicutaneous application, the preparations remain on the scalp after application. These consist of hair lotions or tonics which, as is known, have as their main constituents water, ethanol or isopropanol. However it is also possible to use ointments, gels, creams emulsions and in particular, suspensions. The hair preparation according to the invention is advantageously stored so that it is protected from light and kept at low temperature. At this point reference is also made to the subclaims, which give further advantages and features, which can all be of significance for the present invention.
The preparations according to the present invention may also contain conventional cosmetic substances for caring for the hair and scalp, as well as further known medically active ingredients. Particular reference is made to anti-dandruff and anti-seborrheic products, as well as vitamins, hormones, preservatives and other similar substances, which must obviously be compatible with the constituents according the invention and must not prevent growth of the hair.
Obviously the scalp should be pretreated together with the hair or cleaned with conventional products, so that as far as possible no fatty substances prevent the penetration of the hair conditioner and grooming agent according to the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
The invention is described in greater detail hereinafter relative to a number of non-limitative exemplified embodiments.
EXAMPLE I
Alcoholic hair lotion in the form of a suspension (approximately 1 liter):
400 mm. of absolute ethanol
400 ml. of distilled water
50 g. of vegetable lecithins
Cytochromes, phosphatidyl inositols
Free phosphatidic acids
Lecithins as an extract from 250 g. of fresh bovine heart.
EXAMPLE II
(Preparation Process)
Fatty residues are removed with a sharp knife from 250 g. of fresh bovine heart, which is minced in a mincer-like scraped meat, giving a homogeneous paste which is fed into a 1 liter beaker. This is then topped up to 0.5 liters with distilled water and the paste is then stirred for about 30 minutes with a mixer on the lowest stage.
The aqueous slurry or paste is then placed on a soft folded filter and the aqueous filtrate collected. The meat residues are stored.
The resulting filtrate is briefly boiled, i.e. heated to boiling. However, as soon as a fine precipitate is formed, it is immediately stopped and filtration again takes place. The precipitate is discarded, and the aqueous solution obtained can be termed a cytochrome solution, which is stored for further processing at a refrigerator temperature of 6° C.
The meat residues separated after the first filtration are added to approximately 250 ml. of absolute of ether and stored for two days at ambient temperature in an air-tight, sealed dark vessel with a screw cap. It must be ensured that there is no escape of the ether.
The resulting ethereal solution is then filtered and separated from the meat residues, which are then discarded. The solution is transferred into a 1 liter separating funnel, where the aqueous, reddish solution is separated from the supernatant ethereal, yellowish solution. The aqueous red solution is discarded. During phase separation the separating funnel is left to stand for a short time to improve the phase separation. The ether is then removed at normal pressure using an electrically heated waterbath and the residue is then immediately suspended in the distilling flask with 2×75 ml. of distilled water. It is assumed that this suspension essentially contains phosphatidyl inositols, free phosphatidic acids and lecithins.
This suspension is then combined with the stored aqueous cytochrome solution and then 50 g. of vegetable lecithin are added, which have been extracted from the tonic 3N lecithin (VEB Arzneimittelwerke Dresden). 400 ml. of absolute ethanol are then added to the resulting suspension and the latter may optionally be topped up to 1 liter with distilled water.
EXAMPLE III
100 ml. contain:
______________________________________ethanol 35.0lecithin 5.0L-cystin 0.0001ascorbinic acid 0.0001deionized water ad 100.0______________________________________
The water contains the watery extract as well as the residue suspended in water and prepared from the ether fraction.
EXAMPLE IV
Fatty residues are essentially removed from 250 g. of bovine heart, which is minced in a mincer. 300 ml. of 0.02 m phosphate buffer, pH=7.2, containing 0.1% sodium azide are added and the mixture is stirred in a mixer for 2 to 3 minutes. This mixture is sucked and pressed through a moistened filter having wide pores, and is separated by a high speed centrifuge. The resulting filtrate or the output of the centrifuge respectively is briefly boiled; after cooling down the denatured proteins are separated by a folded filter and discarded. The filtrate (I) containing the cytochromes is stored in the refrigerator until further processing. The remaining meat residues are briefly pressed between filter paper, 300 ml. i-dropanol is poured on them, a drop of tocopherol is added, and the mixture is stirred for 20 minutes. Thereafter the mixture is passed through a Buechner filter and evaporated essentially to dryness in a rotating evaporator. The still moist residue is resuspended with about 100 ml. water and 50 ml. ethanol (Suspension II). The vegetable lecithin (50 g.) is suspended in 500 ml distilled water, stirring vigorously. To this are added, one after the other, the filtrate I and the suspension II, while the mixture is stirred vigorously. Then 350 ml. ethanol are added in a thin stream under stirring and the mixture is topped up to 1000 ml with distilled water.
|
The present invention provides a preparation for conditioning and grooming the hair. The active ingredients are vegetable lecithins, as well as cytochromes, phosphatidyl inositols, phosphatides and phosphatidic acids. Apart from the vegetable lecithins the other active ingredients are obtained by aqueous or ethereal extraction from fresh animal hearts, more particularly bovine hearts.
| 0
|
BACKGROUND OF THE INVENTION
I. Field of the Invention
This invention relates to earth moving equipment which is adapted to be hitched to and pulled behind a tractor. More specifically, the present invention relates to a tractor drawn land arranger having the capability to scrape, level, dig, and carry.
II. Description of the Prior Art
The prior art discloses several types of tractor drawn earth shaping machines. Examples of these machines are disclosed in U.S. Pat. Nos. 1,911,511 to Jordan, 2,483,033 to Baker, 3,110,972 to Waite, and 3,651,589 to Reynolds. The patent to Jordan discloses a tractor drawn device including a frame having a hydraulically actuated scoop operable to either scrape, scoop, or dump dirt. The problem associated with the Jordan device is that the scoop has a limited range of operation, and is forced to function in an inferior manner. Specifically, the Jordan scoop can only level dirt after it is itself full to the point of refusal. As such, the scoop unavoidably removes a substantial amount of dirt before scraping can occur. Such a system leads to problems during operation because it can become a guessing game as to when scraping, as opposed to scooping, will occur, and in some instances the scoop will merely become a heavy dragged object accomplishing neither scooping or scraping. Such guess work often leads to trial and error operation when using the device in unfamiliar soil, and can produce poor results.
The Baker device is a scoop adapted to be mounted on the front of an earth moving implement equipped with a blade. The blade is positioned so as to push dirt into the scoop for carrying and later deposition as desired. The scoop cooperates with the blade and tractor earth moving capability to add a dirt carrying capability previously not associated with the bulldozer.
The Waite device is a tractor drawn earth scooping and carrying device. The scoop includes a frontal shroud portion which prevents scooped earth from exiting the device while in the transport mode. Also, the scoop can be substantially tipped so as to empty the scoop. However, the Waite device is disadvantaged in a manner similar to the Jordan device in that simple scraping cannot be accomplished without some guess work. Instead of simply scraping and moving a layer of dirt in front of a blade, a certain amount of scooping and carrying may take place which will lessen the scraping effect of the blade.
The patent to Reynolds reveals a tractor drawn scraper wherein the angle of inclination of the bucket or scoop can be adjusted somewhat in order to spread dirt collected evenly and smoothly. However, the inventive hydraulic system in this patent is such that the bucket may only be lowered while it is in its horizontal or loading position. Consequently, it becomes difficult to perform controlled scraping and levelling without also scooping and collecting dirt in the bucket.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a earth moving machine of the kind adapted to be pulled behind a tractor which facilitates scraping, levelling, digging and carrying dirt and which is not characterized by the drawbacks of prior art devices.
It is a further object of the invention to provide an earth moving machine of simple and robust construction which may be easily controlled by an operator to efficiently perform any one of several earth moving functions.
Specifically, the invention comprises an earth moving machine adapted to be towed behind a powered vehicle having a horizontally extending frame member with a forward end and a rearward end. Hitch means are disposed at the forward end of the frame member and are adapted to be connected to the powered vehicle for permitting the earth moving machine to be pulled by the powered vehicle. A suspension member is connected to the frame member, and the suspension member has a displaceable portion which is movable relative to the frame at least in a vertical direction. A wheel assembly is secured to the displaceable portion of the suspension member, the wheel assembly having a plurality of wheels adapted to roll along a ground surface on which the earth moving machine travels.
The earth moving machine is further provided with a scoop having a pair of side plate sections rigidly joined to opposite ends of a trough-shaped section and defining a scoop opening. The scoop is pivotally mounted relative to the frame about a pivot location on the frame intermediate the forward and rearward ends thereof. The trough shaped section of the scoop comprises a scoop lip portion located adjacent the scoop opening to which at least one blade means is attached for selectively cutting into the ground surface.
The earth moving machine is provided with first and second motor means. The first motor means is used for controllably moving the displaceable portion of the suspension member relative to the frame member so as to controllably vary the vertical position of the displaceable portion relative to the frame member. Similarly, the second motor means is used for controllably pivoting the scoop relative to the frame so as to controllably vary the orientation of the scoop opening relative to the frame member. More specifically, the second motor means is operative to controllably pivot the scoop between a first and a second position. In the first position, the scoop is oriented such that the scoop opening faces generally upwards and the scoop is effective for carrying a load as the earth moving machine travels along the ground surface, while in the second position, the scoop is oriented such that blade means is positioned rearwardly of the pivot location of the scoop, whereby scraping and levelling of dirt is facilitated.
According to the invention, the earth moving machine includes a plurality of ripper means for breaking up the ground surface which are attached to the frame member and extend downwardly therefrom.
According to another aspect of the invention, the side plate sections are each provided with a reinforcement member, and the scoop is pivotally connected relative to the frame by means of a pair of pivot axles, each pivot axle being secured to the reinforcing member on a respective one of the side plate sections and being received within a complementary opening of the frame member.
In another aspect of the invention the trough shaped section is provided with a first reinforcing member which extends in an axial direction thereof and a second part-circular reinforcing member which extends along an outer circumference thereof. Moreover, the trough-shaped section defines a part-circular cylinder.
In a preferred embodiment of the invention, the first and second motor means comprise hydraulic cylinder assemblies. In conjunction with the hydraulic cylinder assemblies, means are provided for selectively securing a brace between a portion of the machine rigid with the wheel assembly and a portion of the machine rigid with the frame member, thereby relieving a force exerted on the hydraulic cylinder assembly of the first motor means when the hydraulic cylinder assembly of the first motor means is to be maintained in an extended position. Moreover, the earth moving machine includes hydraulic lines leading to the hydraulic cylinder assembly of the first motor means, the hydraulic lines being disposed at least partially within a hollow horizontal member which is located above the scoop and supported on the frame member, whereby the hydraulic lines leading to the hydraulic cylinder assembly of the first motor means are substantially protected during operation of the machine.
In yet another aspect of the invention, the second motor means comprises a pair of the hydraulic cylinder assemblies which are located on opposite sides of the scoop and which are each pivotally connected between the scoop and a frame support member secured to the frame member.
Moreover, according to the invention, pivot axle means are provided on each of the side plate sections for pivotally supporting the scoop relative to the frame member. When the scoop lip is substantially horizontal, a vertical distance from an uppermost portion of the scoop to the pivot axle means is at least three times as great as a vertical distance from the pivot axle means to a bottommost portion of the scoop.
Still another aspect of the invention is characterized in that the blade means comprises a double edged grader blade and the scoop lip portion comprises an angle-iron section to which the double edged grader blade is secured.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 reveals a side view of a land arranger according to the present invention.
FIG. 2 reveals a top view of the land arranger shown in FIG. 1 when the drum-like scoop is in its loaded or travelling position.
FIG. 3 reveals a detailed perspective view of a preferred embodiment of the drum-like scoop.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, there is shown a land arranger 1 comprising a frame 2 which supports a drum-like scoop 3 for pivotal movement about a pair of short pivot axles 4 which extend outwardly from the scoop 3 and are received in complementary openings provided within the frame 2. A pair of vertical support members 5 extend upwardly from the frame 2 and are joined together by a longitudinal member 6 so as to encompass at least the upper portion of the scoop 3. The frame 2 and the members 5, 6 each comprise e.g. box section steel.
The frame 2 is provided at its forward end with a hitch means 7 which is adapted to be connected to a tractor or other working vehicle for permitting the land arranger 1 to be towed. At its rearward end, the land arranger 1 is provided with a box beam axle 9 which carries a plurality of (e.g. four) wheels 8. The axle 9 is adjustably suspended from the frame 2 via a plurality of pivotable trailing arm suspension members 10 and a first hydraulic cylinder assembly 11. The first hydraulic cylinder assembly 11 is pivotally connected to both an outer casing portion of the axle 9 and a suitable non-pivoting portion of the land arranger 1 (such as a bracket secured to the rear vertical member 5). A plurality of adjustable land rippers 12 (the purpose of which will be described hereinafter) extend downwardly from the rearward end of the frame 2. (The distance which the rippers 12 extend downwardly from the frame 2 is, in the preferred embodiment, manually adjustable both side to side and up and down along the frame 2 by means of selectively positioned locking bolts or hydraulic actuators, not shown. The number of rippers and their particular location along the frame is optional.)
The scoop 3 specifically comprises a pair of substantially part-circular side plates 13 which are joined (e.g. by welding) to opposite axial ends of a trough shaped, substantially half-circular cylindrical member 14. As shown in the Figure, the diameter of the side plates is substantially equal to the diameter of the half-cylindrical member. The pair of side plates are, however, angularly offset relative to and about the axis of the half cylindrical member in the clockwise direction, thereby producing a scoop lip 15 at one circumferential end of the half-cylindrical member to which a transverse blade 16 (e.g. made from hardened steel) is attached. A scoop opening 3a is formed above the lip 15 and between the side plates 13, through which dirt (or any other material) may be loaded into the half-cylindrical member 14.
Each of the part-circular side plates 13 are reinforced by a pair of steel reinforcing members 17, 18. The reinforcing member 17 is secured along a diameter of the side plate 13 while the reinforcing member 18 is secured to the side plate 13 substantially perpendicularly to the member 17. (The pivot axles 4 on either side of the scoop 3 are rigidly secured to the reinforcing members 17. When the scoop is pivoted such that the reinforcing member 17 is oriented vertically, the scoop 15 is substantially horizontal, and that the blade 16 occupies a position forward of the pivot axles 4 and beneath the frame 2, a vertical distance from the top of the scoop to the center of the pivot axle is preferably greater than or equal to three or four times the vertical distance from the center of the pivot axle to the bottom of the scoop.) The half-cylindrical member is reinforced by at least one transverse member 19 which secured thereto along an axial (i.e. transverse relative to the travelling direction of the land arranger) length thereof. Additional reinforcement for the half-cylindrical member 14 is provided by a pair of part-circular support members 20 which are secured along the outside circumference of the scoop 3 at axially spaced locations.
The angular position of the scoop 3 is controlled by means of a pair of second hydraulic cylinder assemblies 21 located on opposite sides of the scoop 3, each of which comprises a cylinder end pivoted to a frame support member 23 and a piston rod end 22 pivoted to the reinforcing member 18. Each frame support member 23 is secured (e.g. by welding) one of the side bars 2a of the frame 2. In a preferred embodiment, each of the hydraulic cylinder assemblies 21 and the frame support members 23 may be shrouded by a cover C secured to the respective side bar 2a, as shown by dotted lines in FIG. 1, to protect the cylinder assemblies 21 from falling dirt, rocks, etc. during operation of the land arranger.
The first and second hydraulic cylinder assemblies are independently connected to a convenient source of hydraulic power (e.g. the existing hydraulic system of the tractor) via hydraulic lines L1 and L2, respectively. As seen in FIG. 1, the hydraulic lines L1 extend from opposite ends of the first cylinder assembly 11, through the longitudinal member 6, through an intermediate support 24 (e.g. made from a steel rod extending from the frame 2 and having a bent to present a spiral shape at its free end for receiving the lines L1, as shown), and forwardly of the land arranger 1 to the source of hydraulic power. In operation, a hydraulic pressure supplied to a cylinder end of the hydraulic cylinder assembly 11 through one of the lines L1 will cause an extension of the hydraulic cylinder assembly, while a hydraulic pressure supplied to a piston rod end of the hydraulic cylinder assembly 11 through the other of the links L1 will cause the same to retract. The hydraulic lines L2 extend from opposite ends of the second cylinder assemblies 21, along the frame 2, and forwardly of the land arranger to the source of hydraulic power. Hydraulic pressure applied to the second cylinder assemblies cause the same to extend and retract in a manner similar to that described above with reference to the first hydraulic cylinder assembly 11. A hydraulic control system (not shown) is employed to independently control the amount of hydraulic pressure in each of the lines L1, L2, as will be explained hereinafter. A suitable source of and control of hydraulic pressure can be a conventional hydraulic equipment actuator found on most tractors outfitted for hydraulic equipment operation.
FIG. 3 reveals a presently preferred manner of connecting the blade of the land arranger to the scoop As shown in the Figure, reinforcement members 19',20' are provided on the substantially half-circular cylindrical member 14' in the manner described with reference to the members 19, 20 above. Moreover an angle-iron 28 is secured (e.g. by welding) to the half-cylindrical member 14' at a horizontal marginal area 29 of the member 14'. The angle-iron 28 defines a scoop lip and is itself reinforced by a steel brace 30 secured thereto (e.g. by welding. Moreover, the angle-iron 28 butts against end portions of the reinforcement members 20', whereby the structural rigidity of the angle-iron relative to the member 14' is ensured. A double edged grader blade 31 is releasably secured (e.g. by bolts, rivets, fasteners, etc. as shown at 32) to the angle-iron 28 in such a manner that a downwardly depending edge 33 of the grader blade 31 extends about two inches below the lowermost portion of the angle-iron 28. As shown in the Figure, the side plates 13' and pivot axles 4' are located in substantially the same locations and orientations as described above with reference to the side plates and pivot axles 13, 4 shown in FIGS. 1 and 2. Consequently, according to the invention, when the scoop of FIG. 3 is employed in the land arranger, its blade tip 33 occupies the same positions as shown and described with reference to the blade 16 in FIGS. 1 and 2. The blade may also be equipped with rippers on a leading edge thereof, i.e., in a manner similar to conventional front end loaders or bull dozers, so that ripping can be accomplished when the blade is positioned in the scraping position.
In operation, the land arranger 1 is attached to a source of motive power (such as a tractor) via the hitch means 7. The hydraulic lines L1, L2 are connected to a source of hydraulic power through the hydraulic control system. The hydraulic control system, which is conveniently operated (e.g. via a control panel) by the operator of the motive power source, is used to selectively and independently control the magnitude of hydraulic pressure in the lines L1 and L2 to produce the various modes of operation explained below.
The field travelling mode is used when it is necessary to pull the land arranger 1 from one field location to another. In this mode, a hydraulic pressure is supplied to the lines L1 and L2 so as to cause the cylinder assemblies 11 and 21 to assume their extended positions. The extension of the first hydraulic cylinder assembly 11 causes the trailing arms 10 to rotate (e.g. through an acute angle) in a counterclockwise direction, thus raising the rear end of the frame 2 higher off the ground. This provides a travelling clearance between e.g. the rippers 12, the scoop 3, etc. and the ground. The extension of the second hydraulic cylinders 21 causes the scoop to rotate (e.g. pivot about the axle 4) in a counterclockwise direction. When the second hydraulic cylinder 21 is extended, the opening 3a of the scoop 3 faces generally upwardly. The counterclockwise rotation of the scoop 3 is effective to prevent dirt which may have been accumulated in the scoop 3 from falling out of the scoop when the land arranger is being towed or transported. Once the cylinders 11, 21 have been extended, it is possible to cut off hydraulic communication between the pressure source and the lines L1, L2 (e.g. through the use of conventional cut-off valves), thereby isolating the cylinders 11, 21 from the hydraulic source and maintaining the cylinders 11, 21 in their extended positions. This eliminates the need for continually supplying a high hydraulic pressure to the lines L1, L2 during the field travelling mode. Moreover, once the cylinders have become extended, it is possible to employ a structural brace, such as shown at 25 in FIG. 1, disposed in parallel with the hydraulic cylinders, to remove the operating load from the hydraulic cylinders. In particularly, after the cylinder 11 has been extended, the brace 25 is inserted and secured between the flanges 26 on the rearward vertical support member 5 and flanges 27 (note FIG. 2) on a rearward portion of the box beam axle 9. The brace 25 is thus employed e.g. when travelling long distances to relieve the extended hydraulic cylinder 11 its entire operating load, thereby increasing the durability and reliability of the hydraulic system.
In the leveling or scraping mode, a hydraulic pressure is supplied to the lines L2 so as to cause the second hydraulic cylinders 21 to assume their fully retracted position. The retraction of the piston rods 22 causes the scoop 3 to rotate (e.g. pivot) in the clockwise direction about the axle 4. After the clockwise rotation of the scoop 3, the scoop lip 15 will be oriented at the bottom rear portion of the scoop 3 (relative to the travelling direction of the land arranger 1) and blade 16 (or the blade tip 33 shown in FIG. 3) will point in a downward direction. Once the hydraulic cylinders 21 are retracted, the hydraulic pressure to the hydraulic cylinder 11 is controlled so as to (at least partially) retract the hydraulic cylinder 11. This retraction of the hydraulic cylinder 11 causes the trailing arms 10 to pivot clockwise, thereby reducing (and eliminating) the clearance between the blade 16 and the ground. Further retraction of the hydraulic cylinder 11 causes the blade 16 to dig into the ground, thereby determining a depth of scraping of the blade 16 when the land arranger is towed. Specifically, the hydraulic pressure to the first hydraulic cylinder 11 is precisely controlled so as to effect an optimum retraction of the cylinder 11, thereby producing the desired depth of cut in the scraping operation. Moreover, because the scoop 3 is oriented such that the blade 16 is positioned at a bottom and rearward position thereof relative to the direction of travel, most of the dirt displaced by the blade 16 will merely be pushed by the scoop 3 during a leveling or scraping operation, and only a minimal amount of dirt will be collected within the scoop 3. This facilitates the leveling operation because the operator of the land arranger 1 need not be concerned with collecting too much dirt within the scoop. According to the invention, when the second hydraulic cylinders are fully retracted and the scoop 3 has been rotated (e.g. pivoted) clockwise to its leveling or scraping position, the blade 16 (or alternately, the blade tip 31) is disposed rearwardly of the axle 4 relative to the travelling direction of the land arranger, as shown partially in phantom lines in FIG. 1.
In the dirt carrying mode, the first hydraulic cylinder 11 is initially extended while the second hydraulic cylinder 21 is initially retracted. Next, when the land arranger 1 is travelling over an area in which it is desired to pick up or scrape up dirt from, the first hydraulic cylinder 11 is retracted so that the blade 16 scrapes the ground to a desired depth of cut. As the scraped dirt begins to enter the scoop, the hydraulic pressure to the second hydraulic cylinders 21 is controlled to gradually extend the second hydraulic cylinders, thereby allowing more dirt to be collected within the scoop 3. (As the second hydraulic cylinders are gradually extended, if desired, the hydraulic pressure to the first hydraulic cylinder 11 may be continually adjusted to vary the depth of out of the blade 16 so as to produce the largest possible load of dirt within the scoop 3 within the least amount of time.) Once the scoop 3 is substantially filled, the hydraulic pressure in the lines L1, L2 is controlled so as to fully extend the first and second hydraulic cylinders 11 and 21. Thus the scraping operation is terminated and the land arranger 1, with its scoop 3 substantially filled with dirt, enters the travelling mode. When the land arranger 1 arrives at a location where it is desired to unload the collected dirt, the dirt may be easily unloaded merely by supplying a hydraulic pressure to the lines L2 which causes the second hydraulic cylinders 21 to retract smoothly, thereby rotating the scoop 3 in a clockwise direction. As the scoop rotates in the clockwise direction, the collected dirt falls to the ground through the scoop opening 3a in a controlled and even manner, thereby emptying the scoop.
The ripping mode is used when it is necessary to rip up hard or dry ground e.g. before levelling or scraping can take place. In this mode, the rippers 12 are caused to dig into the ground as the land arranger 1 is travelling. Specifically, the vertical position of the rippers relative to the frame 2 is adjusted (if necessary) before entering the field travelling mode. Once the field travelling mode has been established, the hydraulic pressure in the lines L1 is adjusted to retract the hydraulic cylinder 11 and lower the rear end of the frame 2 relative to the ground until the rippers dig into the ground a desired amount. In this condition, as the land arranger 1 is towed, the rippers 2 will continually act so as to break up the dry and hard ground. Alternately, the ripping mode may be employed in conjunction with other modes of operation of the land arranger 1. For example, the rippers 12 may be used effectively when scraping up dirt in the dirt carrying mode for the purpose of loosening up dirt which is going to be scraped up in the next pass of the land arranger 1.
Although the embodiment shown in the Figures has been described as comprising hydraulic cylinder assemblies for pivoting the scoop 3 and the trailing arms 10, it will be understood that other kinds of motor devices (e.g. pneumatic, electric, etc.) may be used instead of the hydraulic cylinder assemblies, if desired.
While the present invention has been described with certain particularity, it is not meant to be limited to the disclosed embodiment. Those skilled in the art will be aware of numerous modifications which can be made to disclosed embodiment. Therefore, the present invention will encompass the disclosed embodiment and any modifications thereof which will fall within the scope of the appended claims.
|
An earth moving machine is adapted to be pulled behind a tractor or other powered vehicle. The earth moving machine comprises a hitch at a forward end thereof adapted to be connected to the tractor and an axle assembly at a rearward end thereof. A trough-shaped scoop is pivoted on a frame of the earth moving machine at a point intermediate the forward and rearward ends thereof. A first hydraulic cylinder assembly is operable to control the height of the axle assembly relative to the frame, while a second hydraulic cylinder assembly is operable to pivot the trough-shaped scoop relative to the frame. By controlling the fluid pressure supplied to the first and second hydraulic cylinder assemblies, the scoop on the earth moving machine can be used to effect scraping, levelling, digging, carrying, and dumping of dirt. When the scoop is pivoted to its scraping position, a blade provided on the scoop for selectively cutting into the ground surface is located at a position rearward of the pivot point of the scoop.
| 4
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of International Application No. PCT/EP2013/066953 filed on Aug. 14, 2013, which is entitled to the priority of EP Application 12180802.6 filed on Aug. 17, 2012, the disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
A synthetic approach to the pyrazole carboxylic acid derivative of the formula I has been described in scheme 3 of the Int. Patent Publication WO 2011/117264 applying a method disclosed in Hanzlowsky et al., J. Heterocyclic Chem. 2003, 40(3), 487-489.
However, under the acid-catalyzed cyclocondensation conditions described, besides of the desired isomer, also a substantial amount of the undesired N−1 substituted isomer was formed. In many cases, especially on larger scale, this undesired isomer is the major product in the reaction mixture with ratios of up to 70:30 in favor of the undesired isomer, leading to isolated yields of ca. 30% of the undesired isomer, along with ca. 25% of the desired isomer.
Separation of the desired from the undesired isomer, e.g. in the example described above, could only be achieved by applying chromatography techniques. Such methods are not desired for technical scale synthesis, due to economic and ecologic considerations.
SUMMARY OF THE INVENTION
The present invention relates to a novel process for the preparation of a pyrazole carboxylic acid derivative of the formula
wherein R 1 is C 1-7 -alkyl and R 3 is C 1-7 -alkyl which is optionally substituted with halogen or C 1-4 -alkoxy.
The pyrazole carboxylic acid derivative of the formula I can be used as building block in the preparation of pharmaceutically active principles, e.g. for compounds acting as phosphodiesterase (PDE) inhibitors, particularly PDE10 inhibitors. PDE10 inhibitors have the potential to treat psychotic disorders like schizophrenia (Int. Patent Publication WO 2011/117264).
Object of the present invention therefore was to find a synthetic approach which allows a more selective and a more scalable access to the desired pyrazole carboxylic acid derivative of the formula I.
The object could be achieved with the process of the present invention, as described below.
This process for the preparation of a pyrazole carboxylic acid derivative of the formula
wherein R 1 is C 1-7 -alkyl and R 3 is C 1-7 -alkyl which is optionally substituted with halogen or C 1-4 -alkoxy comprises the steps,
a) reacting an oxoacetate of the formula
wherein R 2 is C 1-7 -alkyl and X is halogen with an acrylate of the formula
wherein R 1 is as above and R 4 and R 5 are C 1-7 -alkyl in the presence of a base to form an aminomethylene succinic ester of the formula
wherein R 1 , R 2 , R 4 and R 5 are as above;
b) coupling the aminomethylene succinic ester of the formula IV with an N-protected hydrazine derivative of formula
wherein R 3 is as above and R 6 is an amino protecting group to form the hydrazinomethylene succinic acid ester of the formula
wherein R 1 , R 2 , R 3 and R 6 are as above;
c) ring closing the hydrazinomethylene succinic acid ester of formula VI under acidic conditions to form the pyrazole dicarboxylic acid ester of the formula
wherein R 1 , R 2 and R 3 are as above and;
d) hydrolyzing the pyrazole dicarboxylic acid ester of the formula VII in 3-position with a base to form the pyrazole carboxylic acid derivative of the formula I.
DETAILED DESCRIPTION OF THE INVENTION
Unless otherwise indicated the following definitions are set forth to illustrate and define the meaning and scope of the various terms used to describe the invention herein.
The term C 1-7 -alkyl alone or combined with other groups, refers to a branched or straight chained monovalent saturated aliphatic hydrocarbon radical of one to seven carbon atoms. This term can be exemplified by radicals like methyl, ethyl, n-propyl, i-propyl, n-butyl, s-butyl, t-butyl, pentyl, hexyl and heptyl and its isomers.
Likewise the term C 1-4 -alkyl alone or combined with other groups, refers to a branched or straight chained monovalent saturated aliphatic hydrocarbon radical of one to four carbon atoms. This term can be exemplified by radicals like methyl, ethyl, n-propyl, i-propyl, n-butyl, s-butyl or t-butyl.
The term C 1-4 -alkoxy stands for a C 1-4 -alkyl group as defined above which is attached to an oxygen radical. This term can be exemplified by radicals like methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy or t-butoxy.
The term “amino protecting group” refers to an acid or Lewis acid sensitive substituent conventionally used to hinder the reactivity of the amino group. Suitable acid or Lewis acid sensitive amino protecting groups are described in Green T., “Protective Groups in Organic Synthesis”, 4 th Ed. by Wiley Interscience, 2007, Chapter 7, 696 ff. Suitable amino protecting groups for R 6 can therefore be selected from Boc (t-butoxycarbonyl), Fmoc (fluorenylmethoxycarbonyl), Cbz (benzyloxycarbonyl), Moz (p-methoxybenzyl carbonyl), Troc (2,2,2-trichloroethoxycarbonyl), Teoc (2-(Trimethylsilyl)ethoxycarbonyl), Adoc (adamantoxycarbonyl), formyl, acetyl or cyclobutoxycarbonyl. More particularly Boc is used.
The term halogen refers to fluorine, chlorine, bromine or iodine, particularly to fluorine, chlorine or bromine.
In the graphical representations of compounds of formulae IV and VI, a wavy line indicates the existence of two possible isomers, E- and Z-, across the attached double bond. In this case, the representation refers to both, E- or Z-isomers, as single isomers or as mixtures thereof.
Step a:
Step a) requires the reaction of the oxoacetate of the formula II with an acrylate of the formula III to form an aminomethylene succinic acid ester of the formula IV.
Both the oxoacetates of formula II and the acrylates of formula III are starting compounds which are either commercially available or can be synthesized by methods known in the art.
The ethyl-2-chloro-2-oxoacetate (X═Cl and R 2 =ethyl) and the ethyl 3-(dimethylamino)acrylate (R 4 , R 5 =methyl and R 1 =ethyl) are particularly useful as starting materials.
The reaction is performed in the presence of a base which can be selected from a C 1-4 -trialkylamine ideally combined with a catalytic amount of 4-(dimethylamino)-pyridine or from pyridine. Particular useful C 1-4 -trialkylamines are trimethylamine, diisopropylethylamine or triethylamine.
As a rule the reaction takes place in an aprotic organic solvent, such as in 2-methyltetrahydrofuran, dichloromethane, toluene, tert-butylmethylether or tetrahydrofuran or in mixtures thereof at reaction temperatures between −20° C. and 40° C., particularly between −5° C. and 30° C.
The aminomethylene succinic acid ester of the formula IV can be isolated from the reaction mixture using methods known to the skilled in the art, however in a particular embodiment of the invention, the succinic acid ester of the formula IV is not isolated i.e. synthesis steps a) and b) are combined.
Step b):
Step b) requires the coupling of the aminomethylene succinic acid ester of the formula IV with an N-protected hydrazine derivative of formula V to form the hydrazinomethylene succinic acid ester of the formula VI.
The N-protected hydrazine derivative of formula V is either commercially available or can be synthezised by methods known in the art, e.g. as described in Int. Patent Publ. WO 2011/140425 or by Park et al. in European Journal of Organic Chemistry 2010, pages 3815-3822, or by analogous methods known to the person skilled in the art.
As outlined above once the reaction in step a) is completed step b) can be added without the isolation of the reaction product of step a).
Following the definition of the amino protecting group R 6 as outlined above suitable protected hydrazine derivatives of formula V can be selected from but are not limited to N-Boc-N-methylhydrazine, N-Boc-N-ethylhydrazine, N-Boc-N-n-propylhydrazine, N-Cbz-N-methylhydrazine, N-Fmoc-N-methylhydrazine, N-Moz-N-methylhydrazine, N-Troc-N-methylhydrazine, N-Teoc-N-methylhydrazine, N-Adoc-N-methylhydrazine. N-formyl-N-methylhydrazine. N-acetyl-N-methylhydrazine. N-cyclobutoxycarbonyl-N-methylhydrazine.
Particularly N-Boc-N-methylhydrazine is used.
The reaction can be performed in a polar aprotic or protic organic solvent, such as in 2-methyltetrahydrofuran, ethanol, methanol, ethyl acetate, isopropyl acetate, tetrahydrofuran, tert-butylmethylether, acetic acid, or mixtures thereof at reaction temperatures between −10° C. and 60° C., particularly between 0° C. and 40° C.
If steps a) and b) are combined the reaction can be performed in a polar aprotic organic solvent, such as in 2-methyltetrahydrofuran, tetrahydrofuran, tert-butylmethylether, or mixtures thereof at reaction temperatures between −10° C. and 60° C., particularly between 0° C. and 40° C.
Advantageously, a catalytic or stoichiometric amount of an acid which is not able to affect the amino protecting group such as phosphoric acid or acetic acid can be added.
The reaction mixture can be concentrated in vacuo at temperatures between 10° C. and 50° C., particularly between 15° and 35° C. to drive the reaction to completion.
The resulting hydrazinomethylene succinic acid ester of the formula VI can be obtained in crystalline form after concentration of the reaction mixture.
Further purification can be reached by dissolving the crystalline residue in a lower aliphatic alcohol such as in methanol and by adding water to invoke crystallization, or by recrystallization from an organic solvent, such as tert-butylmethylether.
The hydrazinomethylene succinic acid esters of the formula
wherein Wand R 2 are C 1-7 -alkyl and R 3 is C 1-7 -alkyl which is optionally substituted with halogen or C 1-4 -alkoxy and R 6 stands for an amino protecting group are compounds not described in the art and thus represent a further embodiment of the present invention.
Particular hydrazinomethylene succinic acid esters of formula VI are those wherein R 1 , R 2 and R 3 are C 1-4 -alkyl and R 6 is an amino protecting group selected from Boc, Fmoc, Cbz, Moz, acetyl or formyl.
More particular compounds of formula VI carry the following substitution pattern:
R 1
R 2
R 3
R 6
ethyl
ethyl
methyl
Boc
methyl
ethyl
methyl
Boc
ethyl
methyl
methyl
Boc
ethyl
ethyl
ethyl
Boc
methyl
ethyl
ethyl
Boc
ethyl
methyl
ethyl
Boc
ethyl
ethyl
n-propyl
Boc
methyl
ethyl
n-propyl
Boc
ethyl
methyl
n-propyl
Boc
Step c)
Step c) requires ring closing of the hydrazinomethylene succinic acid ester of formula VI under acidic conditions to form the pyrazole dicarboxylic acid ester of the formula VIII.
The ring closing is usually performed with an inorganic acid, an organic acid or a Lewis acid in a polar solvent such as in ethylacetate, ethanol, methanol, water, tetrahydrofuran, dioxan, acetic acid, or mixtures thereof, at reaction temperatures between 0° C. and 60° C., more particularly between 10° C. and 50° C.
Suitable inorganic or organic acids are, for example, hydrochloric acid, hydrobromic acid, trifluoroacetic acid orp-toluenesulfonic acid. A suitable Lewis acid is, for example, trimethylsilyliodide. Usually hydrochloric acid is used which, can be generated in situ, e.g. by adding a lower aliphatic alcohol, e.g. ethanol to a solution of acetyl chloride in a suitable polar solvent, e.g. ethylacetate.
The pyrazole dicarboxylic acid ester of the formula VII can be isolated from the reaction mixture applying methods known to the skilled in the art, e.g. by adding water to the reaction mixture and by subsequent extraction of the reaction product with a suitable solvent, such as with ethylacetate.
Step d:
Step d) requires hydrolyzing the pyrazole dicarboxylic acid ester of the formula VII in 3-position with a base to form the pyrazole carboxylic acid derivative of the formula I.
The base as a rule is an aqueous solution of an alkali hydroxide selected from lithium-, sodium-, potassium-, or cesium hydroxide or of an alkali hydrogencarbonate selected from sodium- or potassium hydrogen carbonate. Lithium hydroxide is particularly used.
A polar aprotic or protic solvent like tetrahydrofuran, N-methylpyrrolidone, ethanol or methanol, or mixtures thereof may be used for dissolving the pyrazole dicarboxylic acid ester of the formula VII.
The hydrolysis can be performed at reaction temperatures between −20° C. and 80° C., particularly between −10° C. and 30° C.
After completion of the reaction the desired product can be isolated in crystalline form by applying methods known to the skilled in the art e.g. by acidifying the aqueous phase which has been previously washed with a suitable solvent such as dichloromethane.
EXAMPLES
General Part
All solvents and reagents were obtained from commercial sources and were used as received. All reactions were followed by TLC (thin layer chromatography, TLC plates F254, Merck), LC (liquid chromatography) or GC (gas chromatography) analysis. Proton nuclear magnetic resonance (1H NMR) spectra were obtained on Bruker 300, 400 or 600 MHz instruments with chemical shifts (δ in ppm) reported relative to tetramethylsilane as internal standard in the following format: chemical shift in ppm (peak form, coupling constants if applicable, integral). In case of a mixture of isomers, both peaks are reported in the format chemical shift of peak 1 & peak 2 in ppm (peak forms, coupling constants if applicable, integral, isomers). NMR abbreviations are as follows: s, singlet; d, doublet; t, triplet; q, quadruplet; quint, quintuplet; sext, sextuplet; hept, heptuplet; m, multiplet; br, broadened. Purity was analyzed by reverse phase HPLC or GC. Mass spectra were recorded on an Agilent 6520 QTOF spectrometer for ESI (electrospray ionization) & APCI (atmospheric pressure chemical ionization), that is achieved simultaneously (multimode), and on an Agilent 5975 instrument for EI (electron ionization) mode, with either positive (standard case, not especially noted) or negative (neg.) charged ion detection. Further used abbreviations are: IPC, internal process control; DMAP, 4-(dimethylamino)pyridine.
Example 1
2-[1-Dimethylamino-methylidene]-3-oxo-succinic acid diethyl ester
Ethyl 2-chloro-2-oxoacetate (99 g, 725 mmol) was dissolved in 2-methyltetrahydrofuran (800 ml) and 4-(dimethylamino)-pyridine (1.25 g, 10.0 mmol) was added. The mixture was cooled to −5° C. and a solution of triethylamine (76.2 g, 753 mmol) and (E)-ethyl 3-(dimethylamino)acrylate (106 g, 740 mmol) in 2-methyltetrahydrofuran (70 ml) was added via dropping funnel. The mixture was stirred for 3 h at ca. 0° C. After that, 5% (m/m) aqueous sodium chloride solution (250 mL) was added, the mixture was concentrated in vacuo to remove the 2-methyltetrahydrofuran. Ethyl acetate (800 mL) and 5% (m/m) aqueous sodium chloride solution (250 mL) were added, the organic phase was washed with 5% (m/m) aqueous sodium chloride solution (4×250 mL), the combined aqueous layers reextracted with ethyl acetate (2×300 mL) and the combined organic extracts concentrated in vacuo. The residue was filtered over silica gel (500 g, eluting with ethyl acetate/n-heptane 3:2 (v/v)) and the combined filtrates concentrated in vacuo to afford 146 g crude product as an orange oil. The crude product was dissolved at room temperature in tert-butylmethylether (1 L) and cooled to 1° C. Crystallization started at ca. 13° C. The suspension was filtered and washed with few cold tert-butylmethylether to afford 116.6 g of the title compound as light yellow crystals (66%, purity 99.9% by HPLC). MS (GC-split): m/z=243 [M] + . 1H NMR (CDCl3, 600 MHz); δ 1.26 (t, J=7.1 Hz, 3H), 1.36 (t, J=7.1 Hz, 3H), 3.03 (s, 3H), 3.36 (s, 3H), 4.17 (q, J=7.1 Hz, 2H), 4.30 (q, J=7.1 Hz, 2H), 7.85 (s, 1H). The product was isolated as single isomer.
Example 2
2-(N′-tert-Butoxycarbonyl-N′-methylhydrazinomethylene)-3-oxo-succinic acid di-ethyl ester
In a 1500 mL jacket controlled reaction flask equipped with mechanical stirrer, condenser and internal thermometer 2-[1-dimethylamino-meth-(Z)-ylidene]-3-oxo-succinic acid diethyl ester (73.2 g, 301 mmol) was dissolved in ethyl acetate (700 ml) and the solution was cooled to −5° C. A solution of N-tert-butoxycarbonyl-N-methylhydrazine (61.5 g, 421 mmol) in ethyl acetate (60 mL) was added dropwise within 45 min. The reaction mixture was stirred for 30 min at −5° C. Then, it was concentrated in vacuo to a volume of 100 mL and at a constant volume, solvent was exchanged with tert-butylmethylether (1.6 L), resulting in a thick suspension. More tert-butylmethylether (400 mL) was added, the suspension was stirred for 1 h at 0° C., filtered and the precipitate was washed with cold tert-butylmethylether (200 mL). After drying in vacuo (45° C., 20 mbar) the title compound was obtained as a colorless crystalline solid (93.2 g, 90%). MS (ESI & APCI, neg.): m/z=343.15 [M−H] − . 1H NMR (CDCl3, 600 MHz); δ 1.29 (t, J=7.1 Hz, 3H), 1.37 & 1.37 (2t, J=7.1 Hz, 3H, isomers), 1.48 & 1.48 (2s, 9H, isomers), 3.23 & 3.24 (2s, 3H, isomers), 4.22 & 4.24 (2q, J=7.1 Hz, 2H, isomers), 4.31 & 4.35 (2q, J=7.1 Hz, 2H, isomers), 8.07 & 8.12 (2d, J=10.3 Hz & 11.6 Hz, 1H, isomers), 11.51 & 11.53 (2br, 1H, isomers). The isolated product is a mixture of (E)- and (Z)-isomers.
Example 3
2-(N′-tert-Butoxycarbonyl-N′-methylhydrazinomethylene)-3-oxo-succinic acid diethyl ester (telescoped process)
Process Variant 1:
In a 12 L jacket controlled vessel equipped with mechanical stirrer, condenser, internal thermometer and inert gas supply, ethyl 2-chloro-2-oxoacetate (192 g, 158 mL, 1.38 mol) was dissolved under argon at 20° C. in 2-methyltetrahydrofuran (1.34 L). DMAP (2.41 g, 19.3 mmol) was added as solid to the clear, colorless solution. The mixture was cooled to 2° C. internal temperature. A solution of (E)-ethyl 3-(dimethylamino)acrylate (179 g, 1.24 mol) in 2-methyltetrahydrofuran (960 mL) and triethylamine (154 g, 212 mL, 1.51 mol) was prepared in a separate flask by subsequent addition at room temperature, and added to the solution of ethyl 2-chloro-2-oxoacetate and DMAP at a rate that the internal temperature was kept at ca. 2° C. (cooling necessary). The mixture became cloudy, later a thick crystal mash (still stirrable). After 30 min stirring at 2° C., the mixture was warmed to room temperature, filtered, the precipitate was washed with 2-methyltetrahydrofuran (2 L). N-tert-Butoxycarbonyl-N-methylhydrazine (250 g, 254 mL, 1.66 mol) was added to the combined filtrate at 20° C. and the resulting mixture was stirred for 1 h. After that, the reaction mixture was concentrated in vacuo to an orange crystalline residue. The residue was dissolved in methanol (4 L, dark red solution) and water (4 L) was added. The product crystallized spontaneously, the slurry was stirred over night at room temperature. The mixture was filtered, the crystalline precipitate subsequently washed with water (8 L) and heptane (8 L), and dried over night at 50° C. and 12 mbar to afford 352 g of desired product as white powder (83%). M.p. 130.2-131.3° C. MS (ESI & APCI, neg.): m/z=343.15 [M−H] − . 1H NMR (CDCl 3 , 600 MHz); δ 1.29 (t, J=7.1 Hz, 3H), 1.37 & 1.37 (2t, J=7.1 Hz, 3H, isomers), 1.48 & 1.48 (2s, 9H, isomers), 3.23 & 3.24 (2s, 3H, isomers), 4.22 & 4.24 (2q, J=7.1 Hz, 2H, isomers), 4.31 & 4.35 (2q, J=7.1 Hz, 2H, isomers), 8.07 & 8.12 (2d, J=10.3 Hz & 11.6 Hz, 1H, isomers), 11.51 & 11.53 (2br s, 1H, isomers). The isolated product is a mixture of (E)- and (Z)-isomers.
Process Variant 2:
A 300 L reactor equipped with temperature control and vacuum system was charged under nitrogen atmosphere with (E)-ethyl 3-(dimethylamino)acrylate (10.0 kg, 69.8 mol), tetrahydrofuran (80 kg), triethylamine (8.6 kg, 85.0 mol) and DMAP (0.14 kg, 1.25 mol) and the resulting solution was cooled to −5-0° C. A solution of ethyl 2-chloro-2-oxoacetate (11.0 kg, 80.6 mol) in tetrahydrofuran (9 kg) was added dropwise to the mixture at a rate that the internal temperature was kept at −5-0° C. (within ca. 3 h). Then, the mixture was warmed to 15-25° C. and stirred for 40 min or until IPC showed complete consumption of (E)-ethyl 3-(dimethylamino)acrylate. N-tert-Butoxycarbonyl-N-methylhydrazine (13.5 kg, 85.7 mol) was added to the mixture within ca. 5 min. The solvent was removed by evaporation and the mixture was heated to ca. 30-35° C. The evaporation was stopped when tetrahydrofuran distillation ceased (after ca. 4 h). The obtained semi-solid was cooled to 20-25° C. Methanol (39.6 kg) was added and the mixture was stirred for 10 min. Water (110 kg) was added at internal temperature 15-20° C. within 10 min. The mixture was stirred for 2 h at 15-25° C., filtered and the filtered precipitate washed subsequently with water (2×25 kg) and n-heptane (2×16.7 kg). It was then dried at 50-55° C. for 10 h to obtain the title compound as a white solid (21.0 kg, 85.0%, purity 99.2% by HPLC). The isolated product is a mixture of (E)- and (Z)-isomers, product identity was confirmed by 1H NMR and MS.
Example 4
2-Methyl-2H-pyrazole-3,4-dicarboxylic acid diethyl ester
Process Variant 1:
A 12 L jacket controlled vessel equipped with mechanical stirrer, condenser, internal thermometer and inert gas supply was charged with ethyl acetate (2.21 kg, 2.45 L, 25.0 mol) under argon at 20° C. Acetyl chloride (564 g, 511 mL, 7.11 mol) was added (slight exotherm, clear colorless solution). Ethanol (656 g, 826 mL, 14.2 mol) was added at a rate that the internal temperature was kept at 20-25° C. (process-controlled, strongly exothermic, efficient cooling necessary). A suspension of (Z)-diethyl 2-((2-(tert-butoxycarbonyl)-2-methylhydrazinyl)methylene)-3-oxosuccinate (350 g, 1.02 mol) in ethyl acetate (1.05 L) was added via pump at 20° C. to the anhydrous hydrochloric acid solution in ethyl acetate/ethanol. The resulting white suspension became a greenish solution, no exothermy. The mixture was stirred at 50° C. for 2 h. After that, the mixture was cooled to 20° C. and water (6 L) was added (slight exotherm, internal temp. 34° C., rapid phase separation). After phase separation, the aqueous phase was extracted with ethyl acetate (2×1 L). The combined organic extracts were dried (sodium sulfate) and concentrated in vacuo (50° C. jacket temperature, 10 mbar) to obtain 236 g crude product as a yellow oil (99%, purity 96.8% by HPLC). MS (ESI & APCI): m/z=227.1 [M+H] + . 1H NMR (CDCl3, 600 MHz); δ 1.34 (t, J=7.1 Hz, 3H), 1.41 (t, J=7.1 Hz, 3H), 4.02 (s, 3H), 4.30 (q, J=7.1 Hz, 2H), 4.44 (q, J=7.1 Hz, 2H), 7.82 (s, 1H).
Process Variant 2:
A 300 L reactor equipped with temperature control and vacuum system was charged with a solution of hydrogen chloride in ethanol (58.6 kg, assay: 38.6% m/m, 620 mol) and the solution was cooled to ca. 0-5° C. (Z)-Diethyl 2-((2-(tert-butoxycarbonyl)-2-methylhydrazinyl)methylene)-3-oxosuccinate (58.6 kg, 171 mol) was added to the solution in portions within 50 min at 0-15° C. The mixture was then warmed to 15-25° C. and stirred for 3 h, or until IPC showed complete consumption of starting material, tert-Butylmethylether (87.9 kg) was added to the mixture and the mixture was transferred to a 500 L reactor. Water (175.8 kg) was added to the solution at a rate that the internal temperature was kept below 25° C. After phase separation, the aqueous layer was transferred to a 1000 L reactor and it was extracted with tert-butylmethylether (2×87.9 kg). The organic layer was combined in a 500 L reactor and washed subsequently with water (87.9 kg) and a solution of sodium hydrogencarbonate (4.7 kg) in water (87.9 kg), and dried over sodium sulfate (39.3 kg). The mixture was filtered and the filtrate was evaporated in vacuo at 30-55° C. to afford the title compound as a yellow liquid (36.7 kg, 95.3%, purity 99.6% by HPLC). Product identity was confirmed by 1H NMR and MS.
Example 5
2-Methyl-2H-pyrazole-3,4-dicarboxylic acid 4-ethyl ester
Process Variant 1:
In a 63 L steel/enamel vessel equipped with a reflux condenser combined with a thermometer, a mechanical stirrer and an inert gas supply 2-methyl-2H-pyrazole-3,4-dicarboxylic acid diethyl ester (2.84 kg, 12.6 mol) was dissolved in a mixture of tetrahydrofuran (20.0 L) and ethanol (8.5 L) under nitrogen at room temperature. The mixture was cooled to −5° C. and a solution of lithium hydroxide monohydrate (0.53 kg, 12.6 mol) in water (10.0 L) was added within 90 min at −5° C. The dropping funnel was rinsed with water (1.4 L). The reaction mixture was stirred for 95 min at −4° C. to −6° C. After that, the mixture was diluted with dichloromethane (10.0 L) and water (10.0 L) at −5° C. to 0° C. and stirred for 10 min. The organic layer was separated. The aqueous phase was washed with dichloromethane (2×10.0 L). The aqueous phase was acidified to pH<2 by addition of hydrochloric acid (2.75 kg, assay: 25% m/m, 18.8 mol) in water (2.0 L) within 15 min at 20° C. to 25° C. The resulting crystal suspension was stirred for 17 h at 22° C. Then, the crystal suspension was filtered over a glass filter funnel. The filter cake was washed successively with water (7.0 L) and n-heptane (4.0 L). The white crystals were dried in vacuo at 50° C./<5 mbar for 70 h to afford 1.99 kg of the title compound as white crystals (80%). MS (ESI & APCI): m/z=199.1 [M+H] + . 1H NMR (D6-DMSO, 600 MHz); δ 1.25 (t, J=7.1 Hz, 3H), 3.94 (s, 3H), 4.22 (q, J=7.1 Hz, 2H), 7.85 (s, 1H), 14.18 (br s, 1H).
Process Variant 2:
A 1000 L reactor equipped with temperature control and vacuum system was charged with 2-methyl-2H-pyrazole-3,4-dicarboxylic acid diethyl ester (36.5 kg, 161 mol), tetrahydrofuran (253 kg) and ethanol (20.0 L) under nitrogen at room temperature. The mixture was cooled to −10-−5° C. In another 300 L reactor, a solution of lithium hydroxide monohydrate (6.47 kg, 154 mol) in water (135.8 kg) was precooled to 5-10° C. and added dropwise to the 1000 L reactor at a rate that the internal temperature was kept at −10-−5° C. (ca. 3 h). The mixture was stirred at −10-−5° C. for 3 h or until IPC met the specification (i.e. 2-methyl-2H-pyrazole-3,4-dicarboxylic acid diethyl ester<10% by HPLC and byproduct 2-methyl-2H-pyrazole-3,4-dicarboxylic acid<4% by HPLC). Dichloromethane (190.8 kg) and water (146.8 kg) were then added and the mixture was stirred for 20 min. The organic layer was separated, the aqueous phase was washed with dichloromethane (2×190.8 kg), after that the aqueous layer was filtered through an 8 cm plug of Celite and the filtrate was transferred to a 500 L reactor. It was cooled to 5-10° C., hydrochloric acid (18% m/m) was added dropwise within 50 min at 5-15° C. until pH=1-2 (ca. 30 kg). The product crystallized gradually as a white solid. The suspension was stirred at 25-30° C. for 10 h. The precipitate was centrifuged, washed with water (69.4 kg) and n-heptane (2×29 kg) and dried in vacuo at 40-55° C. for 48 h to afford the title compound as white solid (22.2 kg, 69.4%, purity 99.7% by GC). Product identity was confirmed by 1H NMR and MS.
|
The present invention relates to a novel process for the preparation of a pyrazole carboxylic acid derivative of the formula
wherein R 1 is C 1-7 -alkyl and R 3 is C 1-7 -alkyl which is optionally substituted with halogen or C 1-4 -alkoxy. The pyrazole carboxylic acid derivative of the formula I can be used as building block in the preparation of pharmaceutically active principles e.g. for compounds acting as phosphodiesterase (PDE) inhibitors, particularly PDE10 inhibitors. PDE10 inhibitors have the potential to treat psychotic disorders like schizophrenia.
| 2
|
BACKGROUND OF THE INVENTION
This invention relates to apparatus and method for compacting food particles into a unified edible product. More particularly, the invention involves the formation of shaped edible products by binding pieces of food together with pressure and heat.
Illustrative of an edible product composed of pieces of food bonded together is the pasta-based product of U.S. Pat. No. 5,411,752 to Taylor et al. The patent discloses the formation of discrete pieces of cooked pasta with a binding composition into a desired shape. The pasta-based product is proposed as the base or shell of a pizza and as such may be garnished with tomato sauce, cheese, mushrooms, etc. U.S. Pat. No. 4,693,900 to Molinari also describes a shaped pasta product formed of cooked pasta. Zukerman discloses in U.S. Pat. Nos. 3,711,295; 3,961,087 and 5,137,745 shaped food products composed of rice and other cereal grains.
The prior art, however, fails to teach a simple apparatus and method for forming shaped products composed of food particles.
Accordingly, a principal object of this invention is to provide an apparatus and method suitable for commercial production of shaped products composed of food particles.
Another object is to provide an apparatus that compresses and bakes food particles into a unified, shaped product.
A further object is to provide apparatus that minimizes manual labor.
These and other features and advantages of the invention will be apparent from the description which follows.
SUMMARY OF THE INVENTION
In accordance with this invention, an apparatus for forming a shaped product composed of food particles comprises a heated top metal plate and a heated, two-part bottom metal plate, the two parts of which can be alternately moved together and apart. A desired amount of food particles deposited on the bottom plate when the two parts thereof are abutted together can be compressed and baked by applying the heated top plate thereon. Following a selected heating period, the top plate is lifted and the two parts of the bottom plate are separated to release a unified, shaped food product.
The top and bottom plates may be flat to form a pancake-type product but preferably the opposed faces of the top and bottom plates are patterned so that the food particles compressed and baked therebetween will form a three-dimensional product varying in shape from a disk with a turned-up rim to pans or bowls of various configurations. Instead of bowl-like edible products, the invention can form products shaped like hamburgers, frankfurters, croquettes, etc. While the bottom plate will have a hollow or depression and the top plate will have a bulge or protrusion to form a pan or bowl-shaped product, both the bottom and top plates will have hollows or depressions to form a product shaped like a meat ball or bun. For conciseness, a plate having any protrusion will hereinafter be said to have a convex face, while a plate with any depression will hereinafter be said to have a concave face.
Because the products of the invention are formed between heated plates, the term "waffle-type product" will be used hereinafter for conciseness even though the product will not be made of a batter or have the characteristic indentations of popular waffles.
While the apparatus of the invention can be operated manually, its commercial usefulness is maximized by having the top and bottom plates mechanically moved by a timing device so that sequentially the top plate is brought against the bottom plate with its two parts abutted together, then the top plate is removed from the bottom plate and the two parts of the bottom plate are separated and again abutted together, thus readying the apparatus for the next cycle of movements. The timing device can also control dispensing means for depositing a measured amount of food particles on the bottom plate at the start of the cycle before the top plate is brought against the bottom plate.
Manual placement of a measured amount of food particles on the bottom plate at the start of the cycle of movements of both plates is rarely justified because of various common devices that are designed to deliver particulate matter on a timed basis. Extruders and screw pumps are examples of devices used to deliver particulate matter.
The top and bottom plates, preferably made of aluminum, may be heated by steam or other heating fluid or even by combustion of fuel gas, but electrical heating is in most cases preferred. Besides the simplicity of electrical heating elements that can be attached to the top and bottom plates, there is the advantage of simple temperature control.
As for the many types of food particles that can be converted into unified, shaped products, the aforementioned U.S. Patents specify some common examples. To begin with, the term "particle" as used herein is intended to embrace discrete matter ranging in size from about a grain of rice to a pasta shape such as ziti. Such particles may be adapted for cohering in the apparatus of the invention by the addition of a binding agent such as egg white used in the aforementioned Taylor et al patent with cooked pasta. The aforementioned patents to Zukerman illustrate that food particles such as cereal grains can be pretreated in hot water or steam to develop sticky surfaces and thus adapt these cereal grains for use in the apparatus of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
For further clarification of the invention, the ensuing description will refer to the appended drawings of which:
FIG. 1 is a diagrammatic lateral representation of the basic elements of the apparatus of the invention positioned during the baking period;
FIG. 2 is a similar representation of the basic elements of FIG. 1 at the end of the baking period when the baked product is discharged;
FIG. 3 is a further diagram of the basic elements of FIG. 1, positioned to receive a measured amount of food particles from a supply container;
FIG. 4 is a side elevation of an apparatus embodying the three elements of FIGS. 1-3 together with mechanical means for moving the elements;
FIG. 5 is a right end elevation of the apparatus of FIG. 4; and
FIG. 6 is a side elevation like FIG. 4 showing the elements in different positions.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 and FIG. 2 show the basic elements of the apparatus 10 in their closed and open positions, respectively. Top plate 11 has a protrusion 12 and contains electrical heater 13. Two parts 14, 15 that form the bottom plate of apparatus 10 have a recess 16 that is deeper than the height of protrusion 12; the dimensional difference corresponds to the thickness of the shaped food product formed between top plate 11 and two bottom plate parts 14,15. Likewise, periphery 17 of protrusion 12 is smaller than periphery 18 of recess 16 by an amount corresponding to the desired thickness of a turned-up rim on the shaped food product formed by the apparatus. Parts 14,15 are provided with electrical heaters 19, 20, respectively.
With an appropriate amount of food articles adapted for cohesion having been placed on bottom parts 14,15 abutted together, FIG. 1 shows top plate 11 positioned to compress and bake the particles into a unified, shaped product. FIG. 2 shows top plate 11 and bottom parts 14,15 as separated to drop the resulting shaped product at that end of the baking period.
In a simple embodiment of the invention, the surfaces of protrusion 12 and recess 16 are flat and peripheries 17,18 are cylindrical so that the shape of the product formed therebetween is a circular disk with a turned-up rim. Such shaped product formed of cooked pasta can be garnished with tomato sauce that will be retained by the rim. Of course, peripheries 17,18 can be made square, oval or any other shape. Likewise, the surfaces of protrusion 12 and recess 16 can be lightly corrugated or otherwise contoured to provide a desired surface pattern in the shaped food product.
FIG. 3 differs from FIG. 2 in that bottom plate parts 14,15 have been reunited to permit the deposition of food particles in recess 16. As soon as the food particles have been deposited in recess 16, top plate 11 is brought down and pressed against united bottom plate parts 14,15, as shown in FIG. 1, to bake another unified product.
Top plate 11 and bottom plate parts 14,15 are usually formed from thick aluminum stock and electrical heaters are attached thereto along the sides opposite the sides that come together for the molding and baking period. Preferably, the thick aluminum plate 11 and plate parts 14,15 are drilled or milled to provide cavities into which the electrical heating elements fit. All exterior portions of heated plate 11 and heated plate parts 14,15 should be covered with insulation to reduce heat losses and prevent injury to personnel involved with the operation of the apparatus of the invention.
Depending on the type of food particles to be molded and baked into a shaped product, some may tend to stick to the metal parts. In many cases, a Teflon coating on the metal parts will overcome the sticking problem. Chromium plating may be another way of eliminating sticking.
Food compositions deposited on abutted plate parts 14,15 which contain moisture and other volatile components require the release of the volatiles particularly at the beginning of the molding and baking period. Release of volatiles is simply accomplished by permitting top plate 11 to pop up slightly for an instant. A few successive pop-ups of the top plate will usually eliminate the development of any troublesome gas pressure during the baking period.
FIGS. 4-6 show the three basic elements of the invention together with a preferred type of mechanical devices to move the elements. A simple apparatus 30 has a support frame, formed of angle iron or metal tubing, which comprises four legs 31, two side members 32, two end members 33, four uprights 34, two top side members 35, and two top end members 36. Members 32,33 form a rectangular frame supported at its corners by legs 31. Similarly, members 35,36 from a smaller frame supported at its four corners by uprights 34 which are attached to side members 32.
A pair of tubular rails 37 with pedestals 38 are supported by the frame of members 32,33 and are parallel to members 32. A pair of Teflon slide bearings 39 partially encircle each tubular rail 37 as seen in FIG. 5. For simplicity, bottom plate part 41, rod 45, cylinder 46 and bracket 47 have been omitted in FIG. 5.
The two parts 40,41 of the bottom plate are each attached to two slide bearings 39, one on each of parallel rails 37. Bottom plate part 40 is connected by rod 42 to pneumatic cylinder 43 fastened to bracket 44 which is mounted on the frame of members 32,33. Bottom plate part 41 is similarly connected by rod 45 to pneumatic cylinder 46 fastened to bracket 47 which is also mounted on the frame of members 32,33. As shown in FIG. 4, bottom plate parts 40,41, shown in cross section in FIGS. 4 and 6, have been pushed together by their respective cylinders 43,46. At this point in the description, abutted parts 40,41 should be visualized as being without the shaped food product P.
While bottom plate parts 40,41 are pressed together by opposed pneumatic cylinders 43,46, a measured quantity of food particles is dropped on the circular recess 48 in united parts 40,41. Recess 48 has a shallow cylindrical surface 49. Top plate 50 is now pushed down by pneumatic cylinder 51 and connecting rod 52 against the peripheral band 53 of bottom parts 40,41. Cylinder 51 is supported by the top frame of members 35,36. The bottom side of top plate 50 has a cylindrical protrusion 54 with a periphery 55 that is slightly less than periphery 49 of recess 48 in bottom part 40,41. Protrusion 54 can extend into recess 48 only partly so that a narrow space remains between protrusion 50 and recess 48; this space together with the space between cylindrical wall 49 and contoured periphery 55 provides the mold hollow in which the food particles are compressed into the shaped product P, i.e., a circular shell with a rolled up rim 56. Each of plates 40,41,50 are provided with electrical heating elements that are not shown in describing the mechanical movement of these plates.
After a chosen baking period, top plate 50 is pulled up away from bottom plate parts 40,41 by cylinder 51 to expose the circular product P as shown in FIG. 1. Thereupon, bottom plate parts 40,41 are pulled apart by cylinders 43,46 and connecting rods 42,45, as seen in FIG. 6, with the result that circular shell product P drops, e.g., on conveyor 57. Cylinders 43,45 now drive bottom plate parts 40,43 together so that a measured quantity of food particles can be deposited in recess 48 to repeat the sequential movements of top plate 50 and bottom plate parts 40,41 that lead to the formation of shell product P.
Variations and modifications of the invention will be apparent to those skilled in the art without departing from the spirit or scope of the invention. For example, bottom plate parts 40,41 can have two cavities or recesses 48, side by side, into each of which is deposited a measured quantity of food particles. After compression by top plate 50 and a desired baking period, the separation of parts 40,41 will cause two shaped food products to drop out. Also, two or more pneumatic cylinders may be used to move each of bottom parts 40,41 and top plate 50. Accordingly, only such limitations should be imposed on the invention as are set forth in the appended claims.
|
A method for forming and baking food particles into a unified, shaped product, e.g., shaped like pizza, has heated top and bottom plates, the mating faces of which have recesses and protrusions for molding the desired shaped product. The bottom plate is in two parts that are abutted together when food particles are deposited thereon and during a baking period with the top plate placed thereon. After raising the top plate, the two bottom parts are moved apart to release the baked, shaped product. Cooked pasta, such as spaghetti, can be formed into a pizza-like shell.
| 0
|
FIELD OF INVENTION
The present invention relates to a novel solvent based of elastomeric paints and protective coating composition including a major amount of mixture of solvents and minor amount of polymers, cyanoacrylate, mineral oils, pigments, and additives. The coating process can be applied by pad printing, screen printing, brush, and spray. The solvent based elastomeric protective coating composition provides scratch resistance between top coat treatment and painted surface of styrenic block copolymer articles.
BACKGROUND OF THE INVENTION
In recent years, more and more commercial thermoplastic elastomeric products are formed into power tools, electronic and telecommunication equipment, personal care, housewares and appliances, sporting goods, medical devices, industrial machines, packaging, food and beverages, and toys and games. The key features of a thermoplastic elastomer include softness, flexibility, and elasticity, excellent grip characteristics, and good weatherability. These features attract the interest of users and consumers. However, the styrenic block copolymer of thermoplastic compounds contains mineral oil and non-polar polypropylene which have little surface energy. Because the surface of compounds is non-polar, permanent marking becomes difficult to achieve by conventional application methods such as pad printing, screen printing, hot foiling, hand painting and spray coating. The styrenic block copolymer can be commercial grade as soft as 30 shore 00 (near 0 shore A) and as hard as 90 shore A. In general, the composition of the softer grade styrenic block copolymer contains higher amounts of mineral oil only. However, the composition of the harder grade styrenic block copolymer contains more propylene and less mineral oil. The high oil absorbent styrenic block copolymer products have excellent elasticity and elongation but high sensitivity to solvents. If the elongation of elastomeric paint film is much lower than that of the decorated substrate, the applied decorated image will rub off after stretching the substrate.
DESCRIPTION OF THE PRIOR ART
In the prior art, some have approached the paint coating at the surface of styrenic block copolymer. However, the prior art provides limited information regarding the solvent corrosion effect at the substrate surface. Also, no prior art described the scratch resistance of the paint coating when protected by a top coat treatment at the surface of styrenic block copolymer.
U.S. Pat. No. 3,519,466 to Akamatsu, et al., discloses a process for printing on molded articles of a thermoplastic resin or a rubber. This process heats an ink containing a benzene-soluble reactive dye and a wetting agent soluble in benzene in contact with the surface of the molded article of an organo-metallic compound. When the article reaches a temperature over 50° C., but lower than the softening point of the article, the dye will permeate the article and react with the organo-metallic compound to become fixed therein.
The U.S. Pat. No. 6,367,384 to Cass reveals a process for printing a four-color image directly onto a fishing lure. The process begins by preparing the soft bait fishing lure to receive the ink. By employing a four-color pad printing machine, the process prints a four-color image on one side of the fishing lure and may turn over the lure to print on the other side. This process requires pretreatment of the printing articles and an optional clear top coat application upon the lure.
The U.S. Pat. No. 3,991,002 to Sadlo discloses that oily or other difficult-to-adhere surfaces become receptive to a pressure-sensitive adhesive when sprayed, or coated, with an organic solvent solution or dispersion of a certain rubbery styrenic block copolymer and large amount of thermoplastic resin.
The U.S. Pat. No. 5,334,646 to Chen discloses a gelatinous composition and articles formed from an admixture of styrenic block copolymer and plasticizing oil. The gelatinous articles have high elongation, tensile strength, and excellent shape retention under extreme deformation. These properties become essential for the gelatinous composition when used as toys, therapeutic hand exercising grip, shock absorbers, and the like.
The European Patent Application EP0239890 to Blomquist discloses an opaque cyanoacrylate adhesive or coating composition that has a monomeric ester of 2-cyanoacrylic acid and 5% to 50% by weight, based on the monomeric ester, of semi-compatible plasticizers. Plasticizers, useful as opacifiers, come from a non-hydrogen bonding solvent or a moderately hydrogen bonding solvent.
The U.S. Pat. No. 6,503,569 to Sneddon reveals an invention directed to resin coating, adhesives, and cement compositions of styrenic copolymers and terpene solvents. The composition form has high adhesion bonding with molded elastomeric styrene copolymer surface substrates. The invention also has a method of applying the instant coating to substrate surfaces.
The U.S. Pat. No. 7,001,947 to Cordova shows a cyanoacrylate adhesive composition having high shear bond strength, peeling bond strength, tensile strength, impact bond strength, and superior wear characteristics particularly in toy applications. The cyanoacrylate adhesive composition contains (a) up to 20% by weight of cyanoacrylate monomer, (b) a styrene-based elastomeric block copolymer, and (c) a specific solvent which is selected to effect the solution of both components.
The currently available methods to apply images onto thermoplastic rubber compounds include either hand painting or spray coating. Because the composition of thermoplastic rubber compounds contains up to 80% mineral oil, a formed coating film has extreme difficulty sticking to the surface of the substrate due to the non-polar oily substance surface. The prior art thermoplastic elastomer gel articles have good tensile strength and elongation. The prior art make paints by dissolving styrene polymers with solvents alone. Commercial thermoplastic elastomer products have the different durameter from shore 00 to 80 durameter A produced by varying the ratio between styrenic copolymer and mineral oil. With a different amount of mineral oil in the coating composition, the strength of a formed elastomeric gel film varies depending on the elongation of the coating substrate substance. Currently the composition of commercial molded products contains a styrenic block copolymer and mineral oil. Most problems occur when attempting to apply the protective coating to the painting surface of substance and where the cracking and melting of the surface substrate risks the compatibility between the coating film and the molded products. The mineral oil, though, must be in the coating composition which will have more compatibility with molded products. During application of the paint coating, the high polar solvents such as ester and ketone should be avoided. Those solvents will dissolve the surface substrate of molded soft styrenic copolymer products and cause the cracking or melting of the substrate surface. The formed painting film will stretch, strain, and impact much like its substrate under layer and show no splitting. However, the painting film easily scratches off the substrate substance.
The present invention overcomes the difficulties of the prior art. The present invention solves these problems by using the various coating methods such as pad printing, screen printing, hand painting, and spray with an elastomeric gel protective coating to protect the painting image on the surface of the substance.
SUMMARY OF THE INVENTION
A durable and stretchable painting film allows a designated image upon the substrate of thermoplastic elastomeric articles. The film also provides a top coating to form a durable and scratch resistant elastomeric gel with a designated image upon the substrate of the thermoplastic elastomeric articles. The coating adheres to an article with pad printing, screen printing, hand painting, and spraying. The elastomeric gel paint coating contains resins, pigments, solvents, plasticizers, and additives. Furthermore, the elastomeric gel protective coating contains resins, cyanoacrylate, solvents, plasticizers and additives. The paint coating can have other interesting colors and effects provided by fluorescent ink, glitter powder, thermochromic ink, and glow-in-the-dark pigments. There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and that the present contribution to the art may be better appreciated. Additional features of the invention will be described hereinafter and which will form the subject matter of the claims attached.
It is an object of the present invention to provide the elastomeric paint coating by varying the ingredients of formula to form the soft, flexible and stretchable painted image on the surface of elastomeric compounds. It is another object of the present invention to use top coat treatment to provide an elastomeric protective coating by varying the ingredients of formula to form a soft, flexible and scratch resistant protective layer on a painted image on the surface of elastomeric compounds. It is an additional object of the present invention to provide the elastomeric paint and protective coating by pad printing, screen printing, brushing and spraying.
It is an object of the present invention to provide the elastomeric paint coating by varying the ingredients of a formula to form the soft, flexible and stretchable painted image on the surface of elastomeric substrates.
It is another object of the present invention to use a top coating to provide an elastomeric protective coating by varying the ingredients of the formula to form a soft, flexible, and scratch resistant protective layer upon a painted image on the surface of an elastomeric substrate.
A further object of the present invention is to provide the elastomeric paint and protective coating by pad printing, screen printing, brushing, and spraying.
Numerous objects, features and advantages of the present invention will be readily apparent to those of ordinary skill in the art upon a reading of the following detailed description of the presently preferred, but nonetheless illustrative, embodiment of the present invention. Before explaining the current embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
Further objects and advantages of the subject invention will be apparent to those skilled in the art. These together with other objects of the invention, along with the various features of novelty that 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 the specific objects attained by its uses, reference should be had to the descriptive matter in which there is described a preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention includes an elastomeric paint applied on the surface substrate, and followed by a top coat treatment of an elastomeric gel protective coating. The composition of the elastomeric paint contains styrenic block copolymer, mineral oil, solvents, pigments, and additives. However, the composition of elastomeric protective coating has additional alkyl cyanoacrylate for scratch resistance. The coating applies upon the gel paint by pad printing, screen printing, and spraying methods.
Styrenic Block Copolymer
The coating composition is composed of one or more resins, mostly as pellets or crumbs. The resins must dissolve in a suitable solvent or a mixture of solvents. As a main component of the invention, the resins form the elastic film and serve as the carrier for the coloring material used in the coating composition. The selection and combination of the resins determine the utilization of the coating area and the resulting properties: adhesion to various substrates, grades of gloss, and scratch resistance. With the present invention, varying the amount and types of polymers affects the features of coating composition. For example, preferably using triblock, radical block and/or multiblock copolymers, and optionally a diblock copolymer, the printing ink, which has desirable rheological properties, will produce a durable and stretchable elastic film. The polymers used comprise at least one copolymer selected from the radical block and multiblock copolymers. This invention contains at least two thermodynamically incompatible segments, one hard and one soft. In general, in a triblock polymer, the ratio of the segments is one hard, one soft, and one hard or an A-B-A copolymer. The multiblock and radical block copolymer can contain any combination of hard and soft segments. In the optional diblock copolymer, the blocks are sequential with respect to hard and soft segments.
Commercially available thermoplastic rubber type polymers are especially useful in forming the compositions of the present invention. Kraton Chemical Company and Septon Company of America sell commonly used polymers. The most common structure is the linear ABA block type such as styrene-butadiene-styrene (SBS) and styrene-isoprene-styrene (SIS) which is the Kraton D rubber series. Kraton G is another type of polymer preferred for this invention. The copolymer includes a styrene-ethylene-butylene-styrene (S-EB-S) structure. The optionally blended diblock polymers include the AB type such as styrene-ethylene-propylene (S-EP) and styrene-ethylene-butylene (S-EB), styrene-butadiene (SB) and styrene-isoprene (SI). Septon resins are available in either diblock (A-B) or the more common triblock (A-B-A) types. These include a hydrogenated poly-isoprene (S-EP, S-EP-S), a hydrogenated poly-isoprene/butadiene (S-EEP-S) polymer or a hydrogenated poly-butadiene (SEBS) polymer. Depending on the hardness of the surface of elastomeric substrate, various combinations of triblock and radical block in the paint composition are necessary.
Another polymer is chlorinated polyolefin. Commercially available chlorinated polymers are especially useful in forming the compositions of the present invention. Du Pont Company and Nippon Paper Chemicals sell commonly used chlorinated polyolefin. The preferred chlorinated polyolefin compounds are Hypalon CP 826 and Superchlon 830 mws.
The paint and protective coating compositions preferably include resins from about 1% to 12% by weight, more preferably from about 5% to 10% by weight, and still preferably from about 6% to 8% by weight.
Cyanoacrylate
Cyanoacrylates are typically clear, high shear strength adhesives that form an instant bond to a wide variety of surfaces. Cyanoacrylates also form clear, tough, plastic coatings. These coatings provide gloss, scratch resistance, chemical resistance, electrical resistance, and improved structural performance. Cyanoacrylate coatings are generally methyl or ethyl cyanoacrylate-base. Other cyanoacrylates of commercial importance include 2-propyl, n-butyl, and allyl esters. All of these monomers are clear, colorless, low viscosity liquids with pungent odors. The relative benefits and limitation of various types of cyanoacrylate monomers make them appropriate for different applications. Formulation of the protective elastomeric gel coating containing cyanoacrylate causes difficulty because of 1) the sensitivity of cyanoacrylate to contaminants, 2) the extreme reactivity of the cyanoacrylate curing mechanism, 3) compatibility between elastomeric gel and cyanoacrylate, 4) solubility parameter between elastomeric gel, solvent and cyanoacrylate, and 5) the dissolving effect of solvent and cyanoacrylate on the surface substrate.
Mineral Oil
Mineral oil is a highly refined, colorless, and odorless petroleum oil. A preferred mineral oil to mix with thermoplastic rubber of the invention is white mineral oil, generally recognized as safe for contact with human skin. Mineral oil, characterized in terms of its density and viscosity, has a light mineral oil of relatively less viscous than heavy mineral oil.
Light mineral oils are preferred for the invention. Mineral oils are available commercially in both USP and NF grades. USP mineral oils have viscosities that range from 35 to 125 cSt and pour points that range from −12° C. to −20° C. NF light mineral oils have lower viscosities, typically 3 to 30 cSt, and pour points as low as −40° C. The mineral oil may be of technical grade, having a viscosity ranging from 4-90 cSt and a pour point ranging from −12° C. to 2° C. Examples of commercially available suitable mineral oils include Sonneborn® and Carnation® white oils from Witco, Isopar® K and Isopar® H from ExxonMobil, and Drakeol®, Draketex®, Parol® white mineral oils from Penreco Company. The amount of mineral oil in the paint and protective coating should range from about 10% to about 30% by weight based on the total weight of pad printing ink components, preferably from about 15% to about 25% by weight.
Solvents
Solvents differ in their evaporation rates and strengths. The amount of solvent in paints has a major effect on its solvency, drying rate, spraying speed, and adhesion to a substrate. Solvents function as retarders and thinners. Retarders serve when printing speed is slow and when a paint system dries extremely fast. Functioning as diluents in the corresponding paints system, thinners are a mixture of solvents. Mixing paints with thinners in the correct ratio to achieve the desired viscosity is extremely important. The viscosity of the final mixture determines the effectiveness of the elastic coating film transfer. The type and amount of solvents will depend on the resins and pigment used in the paint system. In some cases, the surface substrates also play a role in determining the solvent to be used. The physical evaporation process of the paint induces the drying of elastomeric film on substrate. At the same time the surface substrate of thermoplastic rubber compound partially dissolves, the slight dissolution of the coating surface results in a direct bond between the paints and the substrate.
In general, the commercial styrenic thermoplastic elastomer article has a blend of styrenic copolymer and mineral oil. In the present invention, both the base coat and the top coat use aromatic solvents to increase the adhesion between the elastomeric gel film and the substrate of thermoplastic elastomer products. The very low evaporation rate of glycol ether acetate also reduces the volatility of aromatic solvents. The solvents used include these chemical groups: aromatic hydrocarbons, aliphatic solvent, ester, glycol ether acetate and ketone. For aromatic hydrocarbon solvents, toluene, xylenes, aromatic 100, and aromatic 150 are preferred. In aliphatic solvents, heptane, cyclohexane, hexane, mineral spirits, VM & P are preferred. From the ester group, isopropyl acetate and amyl acetate are preferred. In the glycol ether acetate group, propylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate and ethylene glycol monobutyl ether acetate are preferred. Lastly, cyclohexanone, diacetone alcohol, and isophorone are preferred from the ketone group.
Preferably compositions of the present invention utilize a combination of aromatic hydrocarbon, aliphatic hydrocarbon, glycol ether acetate and ketone. The paint and protective coating preferably includes solvents from about 80% to about 95% by weight, more preferably from about 85% to about 90% by weight.
Colorants
Colorants provide the color tone of the ink and determine its hiding power. Colorants, either organic pigments or inorganic pigments, color a substrate by altering its reflective characteristics. Hundreds of different types of pigment exist. Nature forms some by mineral or vegetable means, but most are synthetic materials. When ink is applied to a substrate, colorants either remain on the surface or tend to fill voids in irregular surfaces. The present invention contains a coloring agent that produces a desired color, preferably organic pigments. The pigments may include those suitable for use in printing ink as is known in the art. Examples of such pigments include: pigment yellow 83 (C.I. 21108), pigment orange 34 (C.I. 21115), pigment red 48:3 (C.I. 15865:3), pigment violet 23 (C.I. 51319), pigment blue 15:2 (C.I. 74160), pigment green 7 (C.I. 74260), pigment white 6 (C.I. 77891), and pigment 7 (C.I. 77266). In this invention, pigment constitutes about 10% to about 30% by weight, preferably in an amount of about 15% to about 25% by weight.
Additives
The additives, normally used in small quantities, adjust the coating compositions for flow, viscosity, or surface characteristics. Adhesion modifiers, matting powder, anti-foam agent, wetting agent, antioxidant, antistatic agents, and flow control agents are a few examples. However, solvents have the most profound effect on coating performance.
EXAMPLE
A 3% by weight of styrenic block copolymer elastomer, known as Kraton 1652, and 7% by weight of mineral oil are dissolved in an 87% by weight solution of an aromatic 150 in a beaker. After a clear solution was obtained, 3% by weight of blue pigment was added to a paint coating solution, and kept stirring until the pigment dispersed homogeneously. A molded, or hot & melt, styrenic thermoplastic elastomer article was provided. The hardness of molded articles varies from shore 00 to 15 shore A. The paints were applied at the surface substrate by spray applicator.
The protective coating was prepared by mixing a 3% by weight of styrenic block copolymer elastomer, known as Kraton 1652, and 7% by weight of mineral oil then dissolving both in an 87% by weight solution of an aromatic 150 in a beaker. After a clear solution was obtained, 3% by weight of ethyl cyanoacrylate was added and kept stirring until the solution dispersed homogeneously. The protective coating was applied at the painted surface of a substrate by a spray applicator, and after waiting 24 hours a hard film forms with good scratch resistance. The applied paints and protective coating film are then subjected to an Eraser Abrasion Test, a surface coating adhesion test, and stretch tests to determine the adhesion, stretch and scratch resistance features of present paint and protective coating compositions, pursuant to ASTM standards.
From the aforementioned description, an elastomeric paint with protective coating upon styrenic block copolymer articles has been described. The elastomeric paint is uniquely capable of applying and coating an image upon a styrenic substrate without the coating fragmenting upon stretching the substrate. The elastomeric paint and its various components may be manufactured from many materials, including but not limited to, polymers, polyethylene, polypropylene, nylon, and composites.
The invention has been described herein with the reference to certain preferred embodiments. It is understood that obvious variants thereon will become apparent to those skilled in the art. The invention is not to be considered as limited thereto.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the design of other structures, methods and systems for carrying out the several purposes of the present invention. Therefore, the claims include such equivalent constructions insofar as they do not depart from the spirit and the scope of the present invention.
|
A process for forming a protective sealant and coating onto a thermoplastic elastic substrate forming an article, including applying a paint coating composition to the surface of the elastomeric formed article, to provide a permanent printed coating thereon, and the step of applying a top coat treatment onto the paint coating composition as previously applied onto the thermoplastic elastomeric substrate forming the article.
| 1
|
BACKGROUND
To market their products, pharmaceutical companies commonly provide samples of the products to physicians, such as sample prescription medications. Typically, a pharmaceutical representative visits a physician's office where the representative discusses with the physician such things as the applications of their product and advantages of their product over competing products. The representative may then provide the physician with free samples of the product (packaged as, for example, blister packs, bottles or sample boxes) to prescribe to patients. This serves two principle purposes. First, it is hoped the patients will like the samples and will want to continue use of the product. Second, it is hoped that the physician will learn from the patients using the samples that the product is effective, causing the physician to prescribe or recommend the product to future patients. There are also other reasons pharmaceutical companies give out samples. For example, pharmaceutical company sponsored patient assistance programs provide both samples and regular prescriptions of medications to those unable to afford the medications.
However, the current process of distributing and prescribing sample prescriptions suffers from numerous problems. First, there is insufficient control over who receives the samples. It is intended that the physicians or pharmaceutical companies give the samples to deserving patients. However, the current system has inadequate control checks, occasionally resulting in samples being misused by patients (e.g. used abusively) or redirected to unintended users. Second, the current system typically has insufficient examination procedures to determine whether or not a sample prescription is right for a particular patient. For example, the patient may be taking a different drug that adversely interacts with a sample medication. Third, the companies providing the products (e.g., pharmaceutical companies) desire better sample prescription tracking information for marketing purposes. Current prescription tracking systems only provide limited information, which is typically inadequate for comprehensive marketing evaluations. Other attributes of the current system are also inefficient for the provision of products from the physician's perspective, including the need for additional paperwork related to ordering or receiving physical stock of the products. This may be in the form of shipping companies requiring signatures to validate receipt of products, which demand more time throughout the process from the physician. The involvement of pharmaceutical company representatives also creates inefficiencies from the regular turnover of personnel, which may result in depleted sample stocks not being replenished in a timely fashion. This disrupts patient care for the physician. Fourth, the current sample prescription system frequently results in waste. For example, pharmaceutical companies frequently provide sample prescriptions to physicians in packaged sample containers that have expiration dates. The packaging itself is expensive, and further waste is added if the samples are not given to patients prior to a sample's expiration date. Disposal of expired samples poses a health risk to the general public in that samples may end up either in dumpsters or flushed into the water system. This has resulted in significant levels of medication found in lakes and municipal water systems. Fifth, after new U.S. Food and Drug Administration (“U.S. FDA”) Black Box Labeling regulations were implemented, all antidepressant packaging inserts inside sample boxes needed to be recalled and replaced with U.S. FDA compliant samples having updated inserts. This resulted in expensive shipping and repackaging costs. Sixth, as a further result of new U.S. FDA Black Box warnings and labeling, pharmaceutical companies have been initiating new policies resulting in discontinuing distribution of many types of samples (e.g., certain classes of medication) to pediatric practices. Consequently, the pharmaceutical companies are requiring the physicians to sign “reinstatement requests” in which the physician certifies that they examine and treat adult patients that require that class of medication. Otherwise, the pharmaceutical company will not provide the samples to the physician. This is an often lengthy process requiring the completion of many forms that may not be readily accessible. This causes delay and additional work for the physician in obtaining samples, which may disrupt patient care. Moreover, there has been no mechanism in place to streamline this authorization process.
The overriding impetus for pharmaceutical companies to move away from traditional sampling is that the cost of packaging, warehousing and distributing the samples, under current practices, is very expensive. This ultimately raises the cost of medications from production all the way down to what the patient eventually pays for their prescriptions. One fashion in which pharmaceutical companies have attempted to address this is by introducing different media, which can be distributed to patients by physicians and taken to a dispensing pharmacy to collect the sample. Current media in the marketplace include paper vouchers and magnetic strip cards, among other things (all of which have expiration dates which leave gaps in initiating new prescriptions written, and require additional storage space in the prescribers' offices). These approaches remove the physician from needing to maintain sample box inventory at their office, but create an inconvenience in the process by requiring the transfer of the media between the participants in the sample chain. While it does create a partial electronic record of the dispensing of the sample to the patient, many significant data gaps in the sample's life-cycle remain.
Some attempts have been made to remedy some of the above-described problems. For example, some are attempting to implement radio frequency identification (“RFID”) systems. However, such RFID systems have many disadvantages, including, among other things, being unreliable. Other gaps in the RFID systems as applied to pharmaceutical company samples include a maximum radius for tracking, high expense in tracking to the individual package (beyond a bulk shipment), and the absence of recipient information (e.g. gender, age, diagnosis code, etc.) that is critical in the distribution of a healthcare product such as a prescription drug sample.
For the foregoing reasons, there is a need for improved systems and methods for giving sample prescriptions.
SUMMARY
The preferred, non-limiting embodiments of the present invention are directed to systems and methods that satisfy the need for providing sample prescriptions electronically (thereby bypassing the need for packaging and shipping sample medications) and creating a complete data set of information regarding the life-cycle of the sample prescription. A sample prescription system having features of the present invention comprises a management module that stores files corresponding to sample prescriptions. Each corresponding file is linked to a unique sample code. The sample code and linked file together comprise an electronic history of the sample's life-cycle, which is built dynamically over time into a comprehensive code containing all information relevant to a prescribed sample and it's path to consumption. The sample codes are allocated to subscribing pharmaceutical companies, who in turn distribute the sample codes to physicians. Prior to the allocation of the codes the code itself is an “empty set” devoid of any data except a unique coded identifier, or Universal Tracking Pharmacy Code (‘UTPC’). The unique UTPC is the coded string that identifies the life-cycle of the prescription or sample to which it is assigned, once it is distributed by an authorized physician. As a matter of form, the present invention provides for an infinite number of UTPCs to be available to allocate to physicians. UTPCs may ultimately be attached to several fields or character strings that are commonly used in prescription tracking for which there are already recognized standards (e.g. prescription number, national drug code, etc.). Inherent in this process is the ability to control the distribution of codes for the class/type of medication they represent and the physicians that are chosen to have access to samples of that drug. This automatically reduces exposure to pharmaceutical companies since physical samples or sample media are not physically present in the environment to be misdirected to non-approved physicians/specialties or patient groups for which the medication is not U.S. FDA approved. The physicians use the codes to assign specific samples to patients by transmitting the sample code, along with a prescription, to a dispensing entity, such as a pharmacy, for delivery to the patient.
Throughout the above-described process, information about the sample prescription is acquired by a management module and appended to a file corresponding to the sample code. Such information may generally include information about the prescribing physician, the dispensing pharmacy and the patient using the sample prescription. Dates and times of actions connected to the samples may also be captured.
The entire electronic process together creates a uniform utility for tracking sample information throughout it's life-cycle from allocating the sample code to the physician, to the physician assigning the sample code to a drug and patient, to the recipient patient obtaining the prescription from an appropriate dispensing entity.
Several parties may derive benefit from the uniform utility that captures this information such as a pharmaceutical company, governmental or regulatory agency, or the physician or physician group through which the sample codes were originally provided. They may have access to portions of the aggregate information stored in the files, which may advantageously be used for marketing purposes.
A first aspect of the present invention includes the creation of a permanent relationship between two distinct data sets, which include a static pharmacy tracking code known as a Universal Tracking Pharmacy Code and a linked file that dynamically builds as information is added. A first half of the tracking code is possessed within a pool with alpha-numeric sequences that may be put into building a bar code that may be used by pharmacies and pharmaceutical companies. A management entity owns the tracking codes and corresponding files (which together comprise a unique code) for their use and sale and manages all access to the codes and files. The management entity builds and administers these codes. Hospitals, clinics, pharmacies, insurance companies, governmental agencies and the like may reference these codes to obtain tracking information. Use of a code itself is tracked, so that any time it is used the sample prescription system tracks its use by connection to partner companies through which the codes pass for routing instructions (an example of this is a pharmacy claim ‘switch’ company, such as NDC Health or Emdeon). As data is collected, it is appended to files corresponding to the assigned code. The management entity may then disseminate selected tracking information to subscribing entities for a user fee.
A second aspect of the present invention is an aggregate code which is born of the related data sets created by the first aspect of the invention. This aggregate code is referred to as a “Universal Sample Pharmacy Code” (or “USPC”). A USPC is a UTPC that pharmaceutical companies purchase to use for direct attachment to distribution of samples or prescriptions, then receive data to track the life cycle of that sample or prescription. The USPC is a UTPC which has been attached to a file that is populated with information captured from numerous sources throughout the life-cycle of the sample or prescription. As described above, the USPC is comprised of a UTPC and an electronic file which includes all available history of that code. The USPC may be embodied in an encrypted character string of a 128-bit or 256-bit key. As the life-cycle content is built into the file attached to the UTPC, it is then encrypted into the character string so that a user with the encryption key may access the current data. A physician writing a prescription may pull from a preset pool of sample codes allocated by a pharmaceutical company. The pharmaceutical company may also select the number of sample codes they wish to allocate (e.g., 50,000, 100,000, or over a million codes). The pharmaceutical company may choose to allocate and terminate their initial sample codes via a secure electronic interface by authorized representatives of the pharmaceutical company.
In a third aspect of the present invention, the aggregate code, including both the UTPC code and the USPC, are encrypted into a data packet and may additionally have bundled with them software/next directions and a self-executing program for each pharmacy to universally open up an information window enabling the pharmacy to read information contained in the codes. The software may additionally comprise import/integrate software that provides for seamless integration of code information in a pharmacy's computer system. This integration may allow a pharmacy system to directly feed the sample code information into their transmission for adjudication. Access to read the data carried in the code for manual entry to initiate adjudication shall also be supported in the software. When implemented, and after the sample prescription is either given to the patient, picked up, mailed, or otherwise delivered to the patient, the code may support creation of a bar code to be used for scanning by a conventional scanner. This may bundle the code into an encrypted state within the data packet that is now represented by a bar code. It may then be sent to a sample prescription manager as instructed in the software attached to any scanning system able to read the bar code.
In a fourth aspect of the present invention, the users contract with the management entity for the sample prescription services. The contracted user is provided with a unique “unbundler” code (also referred to as a “key”) enabling the user to view the sample prescription information contained in the aggregate code. If the code has been encrypted, the key would allow for the activation of the software that functions to decode the character string that represents the UTPC and attached files (the USPC). The contracting users (e.g., pharmaceutical companies) pay for use of the sample prescription services via electronic deposit automatically as invoiced electronically, given the high number of codes used.
In a fifth aspect of the present invention, a first part of the USPC may contain the following information and is present in the USPC after the pharmaceutical company allocates the code to the physician:
A) 11-digit National Drug Code (“NDC-11” which includes the drug manufacturer, dosage and form, and package type) B) Quantity available C) Terms of patient contribution (e.g. free sample, dollars-off, number of refills available) D) Version of medication (e.g., in capsule, tablet or liquid form) E) Bin number F) Group number, and other processing variables to support adjudication G) Unique physician number or NPI (“National Provider Identification”) number
In a sixth aspect of the present invention, other parts of the USPC are added at various steps after the corresponding prescription is written and dispensed and new information is communicated back to the USPC Management Module. These parts of the USPC may contain the following information:
Date prescription written Sig (directions) Diagnosis code Zip code of origin/dispense zip code Hospital/clinic of origin code (inpatient vs. outpatient) Patient Social Security number, date of birth, age, sex Payer coding Date prescription filled and received by patient Dispensing pharmacy data
In a seventh aspect of the present invention, the first half of the USPC as noted above is in a pool of sample codes that a physician may pull from to write prescriptions. These codes are created, distributed, attached to active prescriptions, and transmitted to the dispensing pharmacy electronically. This replaces the pharmaceutical company's need to produce wasteful sample boxes of medications. Instead, the codes are purchased by pharmaceutical companies for less than what it costs them to produce samples of their medications (effectively an electronic trial sample code). The codes are then housed in a central location for national distribution by local pharmaceutical representatives or other centrally located authorized representatives. The actual product is then provided to the receiving patient from the regular operating inventory of the dispensing pharmacy upon request from the authorized patient.
After the aggregate USPC code is built with collected data following a prescription being dispensed to a patient (e.g., a first part of the code plus other parts of the code), then contracting users, such as pharmaceutical companies, may purchase select information that has been built into the USPC. Preferably, the contracting user is only granted access to confidential information as dictated by current laws such as, in the United States, the Health Insurance Portability Accountability Act (“HIPAA”). For example, information that may be restricted from contracting subscribers includes a patient's social security number and other personal, confidential information. The other non-confidential demographic information may be used by pharmaceutical companies, as an example, for tracking all sample prescriptions. If a USPC arrived at the filling pharmacy and was designated in the first part of the code as a free sample, then it would allow for the sample prescription to be filled for no cost to the patient. Other structures of an offer such as a dollar-amount off the prescription may be administered through the code. The dispensing pharmacy will be reimbursed by the pharmaceutical company for the cost of filling the sample prescription via the functions of a pharmacy benefit manager (“PBM”). The PBM would verify the code carries the financial terms (e.g. number of units, free, dollar-amount off) intended by performing an eligibility function on the code submitted from the dispensing pharmacy. The PBM also becomes a central vehicle for capturing dispensing and patient data for relay back to the Management Module which builds on the code and the corresponding data files, which ultimately complete the entire USPC aggregate code. Desirably, the cost for distributing promotional products in this fashion is less than what a pharmaceutical company pays for fulfillment and distribution of samples using current methods.
Although the aggregate USPCs, when completed, would be available, the pharmaceutical companies would not have to buy the accompanying data if they choose not to. All of the USPCs (UTPCs and corresponding data files) are encrypted, and pharmaceutical companies are only able to get the tracking information if they purchase a final key which grants them access to the USPC (UTPC and corresponding data files).
In an eighth aspect of the present invention, in order to overcome barriers that organizations may have regarding these codes and development/implementation on their system, “turnkey” software is provided so that little or no programming is required on behalf of any users of the sample prescription system. This enables the users to interface and integrate with software already installed on the users' organization's system(s).
A ninth aspect of the present invention is that the management entity stores prescription information in a central database, protected by security measures to ensure that confidential information is not unlawfully obtained.
A tenth aspect of the present invention is centralizing and standardizing prescription sampling and tracking. In this manner the present invention serves as a neutral clearinghouse and utility service for manufacturers that provide samples as promotional products.
For purposes of summarizing the invention, certain features, aspects and advantages of the invention have been described herein above. It is to be understood, however, that not necessarily all such features, and aspects are used, and advantages 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 feature, aspect or advantage as taught herein without necessarily achieving other advantages or using other aspects as may be taught or suggested herein.
DRAWINGS
These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description and accompanying drawings where:
FIG. 1 is a diagrammatic illustration of the general architecture of one embodiment of a sample prescription system of the present invention;
FIG. 2 is a flow diagram of one embodiment of the sample prescription system process in accordance with the present invention;
FIG. 3 is a diagrammatic illustration of an embodiment of a sample code and illustrates a flow of information among components of the present invention; and
FIG. 4 A-F is a flow diagram of a further embodiment of the sample prescription system process in accordance with the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
A. System Architecture
FIG. 1 illustrates one non-limiting embodiment of the general architecture of a sample prescription system 100 (herein also referred to as “SPS”) that operates in accordance with the present invention. The SPS 100 includes a prescriber module 101 , a pharmaceutical module 102 , a pharmacy module 103 and a management module 104 , that communicate via communication mediums 113 , such as an electronic prescribing switch 114 , and the Internet 115 .
1. Prescriber Module 101
The prescribing module 101 may be implemented using any type of computing device for operating a web browser 106 . The computing device is defined as a device that enables a user to browse a remote web site through the communication medium using, for example, a web browser, such as Microsoft® Internet Explorer developed by Microsoft Corporation. Examples of the computing device include a desktop computer, a lap top computer, a personal digital assistant, an interactive wireless communications device, a handheld computer, a computer server, or the like, which connects with the communication medium. Additionally, the computing device may include any number of known peripheral devices that cooperate with the computing device, such as a printer, a scanner, a bar code scanner, facsimile machine and the like.
The prescriber module 101 is located where sample prescriptions are prescribed, such as a medical private practice, a hospital, or a clinic. In general, the prescriber module 101 enables a prescribing entity, such as a physician, to access the management module 104 to distribute sample prescription codes and prescribe a sample to a patient via an electronic prescription switch. The distribution of a code to a patient is paired with the electronic prescription when completed in the prescriber module 101 and sent into the communication mediums 113 . The paired data may then be split into two transmissions at the management module 104 , with the electronic prescription being submitted to the electronic prescription switch (denoted as eRx switch) 114 for ultimate delivery to the chosen pharmacy. A switch refers to an organization that receives live pharmacy claims from a pharmacy management system and then routes them to the appropriate claims processor for PBM functions. Once the claims processor adjudicates the claim and sends a response, the switch also returns the adjudicated claim from the claims processor to the management module 104 from where it originated. The USPC is updated with the new information received at the management module 104 during this step and is then stored to be made available to other users with appropriate access.
2. Pharmaceutical Module 102
The pharmaceutical module 102 is implemented using one or more computing devices for operating a web browser 107 . The pharmaceutical module 102 may be located at a company's physical facilities. It is also contemplated that the pharmaceutical module 102 comprises a main server located at a pharmaceutical company's facilities, which may be remotely accessed by other computer devices. For example, pharmaceutical sales representatives may access the pharmaceutical company's server via a wireless personal digital assistant device, which advantageously enables the sales representatives to access the management module 104 remotely. Alternatively, the wireless personal digital assistant device may be capable of accessing the management module 104 directly without having to first access the pharmaceutical company's server.
The pharmaceutical module 102 contains within it various levels of permission to assign drugs, patient terms, and physicians to sample codes. Specifically, it is contemplated that an appropriate party at the pharmaceutical company has protected administrative entry screens to control the drug chosen for available sample codes and how many are available to a given employee and physician. The party also controls the patient terms (e.g. free or patient contribution, number of refills, etc.) and establishes parameters for the code distribution such as a maximum number of codes for a specific product to a specific physician, and may also designate the maximum number of authorizations allowed per patient.
3. Pharmacy Module 103
The pharmacy module 103 is also implemented using one or more computing devices for operating a web browser 108 . The pharmacy module 103 is at a location that dispenses prescriptions and sample prescriptions. The pharmacy module 103 is capable of accessing the management module 104 and receiving information sent from the management module 104 , such as emails, via the communication medium 113 . The pharmacy module may also be used to apply a key to the sample code in the management module and access the stored data for that sample code. The pharmacy module 103 may also contain an application to receive electronic prescriptions from the electronic prescription switch 114 in addition to the tools to access the management module 104 .
4. Management Module 104
In general, the management module 104 provides functionality for managing sample prescriptions utilized in the SPS 100 . Typically, the management module 104 is operated by a business entity that handles various sample prescription order processing tasks, collections, distribution of information and customer service tasks associated with the SPS 100 . The management module 104 may include software 109 that implements an online registration process (not shown) for enabling other entities, such as physicians, physician practice groups, hospitals, clinics, pharmaceutical companies, pharmacies, and so forth, to register as members. The management module 104 contains administrative screens which allow various users with the appropriate privileges to establish terms to apply to the codes, as referenced above under Section 2, ‘Pharmaceutical Module 102 .’ The management module 104 may identify customers using any appropriate method, such as cookie retrieval or log-in procedures. Additionally, communications between devices of the SPS 100 preferably use an authenticated certificate in accordance with governmental regulations, such as U.S. Drug Enforcement Administration (“DEA”) policy.
The management module 104 illustrated in FIG. 1 includes components that may be used to implement the above-described features. The exemplary management module 104 includes a web server 110 , which accesses a database collection 111 that includes a database of sample prescription information 112 and related content. The web server 110 also manages a web site accessible via the communication medium 113 . The web server 110 may also process requests made with an appropriate permission level or de-coding key for the sample prescription information contained in the aggregate code and the attached files, review and authenticate the sample prescription information, and send and receive sample prescription information to and from the prescriber module 101 , the pharmaceutical module 102 and the pharmacy module 103 via the communication medium 113 . The information may be used to provide sample prescriptions to patients via submission to the electronic prescribing switch 114 , track the sample prescriptions and generate sample prescription marketing reports among other functions.
The web server 110 communicates with management module software 109 as well as the database collection 112 to manage the sample prescription process and to provide prescription related information to appropriate users. Additionally, the management module software 109 generally implements the functions of the management module 104 , including releasing information, populating the database 111 and operating the management module web site.
a. Database Collection 111
The database collection 111 illustrated in FIG. 1 includes the database 112 for storing sample prescription related information. The database 112 contains a plurality of files, each designated by a unique encrypted alphanumeric sample code corresponding to a sample prescription. In other words, each sample prescription used in the SPS 100 has a corresponding file in the database 112 that, together with the tracking code, represent the aggregate sample code that is the USPC. The sample code may be randomly generated or may be generated using a convention where the sample code has specific meaning. Specifically, in the latter instance, a person with knowledge on how to read the sample code may obtain information about the corresponding sample prescription by analyzing the sample code. For example, the sample code may have a first portion that identifies the pharmacy company of origin, a second part that identifies the type of drug corresponding to the prescription, and the like.
The files in the database 112 contain fields that are capable of being populated with desired prescription information as the corresponding sample prescription moves through the SPS 100 process and data from different users is returned to the management module 104 . In general, the fields contain information that a pharmaceutical company using the SPS 100 would find useful and information that will aid in the sample prescription distribution process. Examples of such fields include:
NDC-11 code for the drug Sample prescription quantity available Terms of patient contribution (e.g. free sample, dollars-off, number of refills available) Date prescription written Sig (i.e. directions how the medication is to be administered to the patient) Diagnosis code (in format of ICD9 & ICD10 nomenclature) Unique physician number, NPI number or DEA number Zip code of origin or sample prescription dispensing location zip code Hospital or clinic of origin code (e.g., inpatient or outpatient) Patient information, including social security number, date of birth or age, and sex. (Advantageously, the patient's information may be used by the government authorities to prevent or apprehend “physician shoppers,” and flag or alert the prescription filling pharmacy that the patient recently had a similar prescription filled.) Payer coding Date sample prescription filled and other dispensing pharmacy data related to this transaction Sample code activation or deactivation date Version of medication (e.g., type of tablet, capsule or liquid) Prescription BIN number Drug representative unique identifier for pharmaceutical company reference
In an exemplary embodiment, the fields are populated by inputting information into the SPS 100 by the prescriber module 101 , the pharmaceutical module 102 , the pharmacy module 103 or from another source, such as a pharmacy benefit manager or electronic prescription switch, that has the desired information. The information may be inputted in any number of ways known by those skilled in the art, such as automatic uploading when a triggering event occurs during the SPS process or manual inputting of the information.
In connection with the database collection 111 , in one embodiment, there may be several processes (not shown) such as ID generators, number generators and temporary storage units that may work with the database collection. Furthermore, it is recognized that the database collection 111 may be implemented using a variety of different databases such as relational databases, flat file databases, or object oriented databases. Moreover, while the database collection depicted in FIG. 1 is comprised of one database 112 , it is recognized that in other embodiments, the database collection may include other databases. In addition, the database collection may be implemented as a single database with separate tables or as other data structures that are well known in the art such as linked lists, stacks, binary trees, and so forth.
5. Communication Mediums 113
The communication mediums 113 include an electronic prescription switch 114 and the Internet 115 , though a wide range of interactive communication mediums may be employed in the SPS 100 as is well known to those skilled in the art via encrypted, HIPAA compliant encoding.
6. Other Embodiments
While FIG. 1 illustrates an embodiment wherein the management module 104 primarily implements the SPS process, it is recognized that in other embodiments, the management module 104 may include or work in conjunction with one or more third parties (not shown) to provide the sample prescription service. In some embodiments, the third party web site may receive requests for samples and/or send sample prescriptions to the pharmacies. In other embodiments, a pharmacy benefit manager may be central to communicating data between the management module and the users that interact with the sample code along the chain to a patient receiving a sample.
Furthermore, although the embodiments described herein use web site technology to disseminate information, a variety of electronic dissemination technologies may be used.
In addition, although the SPS 100 is described using “a” management module 104 , it is recognized that the management module 104 may comprise multiple different sites.
B. Sample Prescription Process Using the Sample Prescription System 100
A description of the sample prescription system process using the sample prescription system 100 is described with particular reference to FIG. 2 . In a step 200 , a pharmaceutical company, via the pharmaceutical module 102 , requests an allotment of sample codes from the management module 104 . In an exemplary embodiment, the pharmaceutical company uses the pharmaceutical module 102 via web browser 107 to accesses the web site of the management module 104 . Once logged into the web site, the web site provides an option for the pharmaceutical company to request an allotment of sample codes. Additionally, the web site prompts the pharmaceutical company to submit information about the sample prescriptions that will be used in conjunction with the sample codes. This information may include the number of requested sample codes, the corresponding sample prescription medication type, the terms available for the patient with that sample code, length of time the pharmaceutical company desires sample codes to be valid and any other pertinent information available at this time.
In a step 201 , the management module 104 generates a number of sample codes corresponding to the number of sample codes requested in the step 200 . An alternate mode of generating codes is a virtual “infinite” number of codes for the pharmaceutical company to activate sequentially. The management module 104 also creates a file corresponding to each sample code, which is stored in the database 112 . Thus, each sample code corresponds to one sample prescription that the pharmaceutical company plans to distribute. Furthermore, information obtained during the step 200 is populated into the corresponding sample code file to build the aggregate sample code, or USPC.
In a step 202 , the management module 104 provides the sample codes to the requesting pharmaceutical company. In an exemplary embodiment, the management module 104 emails a list of sample codes that correspond to the files created in the step 201 . Alternatively, the pharmaceutical module 102 may be capable of downloading the list of sample codes or otherwise accessing the list of sample codes via the management module web site. Of course, other methods of transmitting the sample codes may also be used, such as via regular mail or faxing.
In a step 203 , the pharmaceutical company activates allotments of the sample codes and provides them to prescribing physicians, which may be accomplished in any number of ways. For example, a pharmaceutical company sales representative may visit the physician's office and discuss the sample prescriptions with the physician. The sales representative may then use a wireless personal digital assistant to access the list of available sample codes corresponding to the desired sample prescription parameters and transmit (e.g., via email, fax or other electronic means) a number of sample codes to the physician for the physician's use. The sample codes may be transmitted with prepared hard copy prescriptions (e.g., paper form) having the physician's demographic data for simplifying the prescription process. Alternatively, the sales representative may provide the sample codes to the physician by “reserving” a number of sample codes. The physician may thereafter access the reserved sample codes via the management module web site.
In a step 204 , sample prescriptions are prescribed to a patient. Here a patient visits a physician whom was previously allocated sample codes as discussed above. Alternatively, the patient-physician examination may be performed via a real time video conferenced appointment. The physician examines the patient and determines that the patient should take a particular medication. The physician then accesses the list of sample medications allocated to him by, for example, accessing the management module web site or a third party e-prescribing entity's web site.
There are a number of alternative ways in which the physician can prescribe the sample prescription. In one embodiment, the physician accesses the management module web site or third party e-prescribing entity if the prescriber module 101 includes access to both. The physician then navigates to an application of the web site that enables the physician to “e-prescribe” the sample prescription. In general, “e-prescribe” means that the physician can use a computer device to transmit the prescription to a medication dispensing facility, such as a pharmacy.
The “e-prescribe” application prompts the physician for information required to fill the prescription. This information may include the desired dispensing location (e.g. pharmacy location), patient information (e.g. name, age, sex, and other identifiers) and sample code, if any. If a sample code is provided, then the prescription is for a sample prescription corresponding to the sample code. The sample code may be verified by submission to a pharmacy benefit manager as the prescription number or the patient ID field. The physician then submits the prescription, and the information is routed to the management module 104 . The management module 104 may then perform any number of processes, including populating the fields of the file corresponding to the sample code in the database 112 and checking the database collection 111 to determine whether or not the patient was recently prescribed similar medication that may indicate unlawful conduct (e.g. “physician shopping”). The SPS 100 also may authenticate the prescriber by verifying that the prescriber is lawfully able to prescribe the medication by referencing the prescriber's DEA designation.
In a step 205 , the prescription is sent to a participating dispensing location. In an exemplary embodiment, the “e-prescribe” application transmits the prescription from the management module 104 to the pharmacy module 103 via the communication mediums 113 . The communication mediums may or may not include a combination of the electronic prescription switch 114 and the Internet 115 . In alternative embodiments, the prescription may be sent via fax. For example, a hardcopy of the sample prescription, which was provided by pharmaceutical representative, may be used.
In a step, 206 , before reaching the pharmacy module 103 , the prescription is routed to an organization that administers the electronic prescription switch 114 , such as SureScripts, located in Alexandria, Virginia, and having a web site at the web address:
www.surescripts.com, or RxHub, LLC, located in St. Paul, Minn., and having a web site at the web address: www.rxhub.net. The transmission to the electronic prescription switch 114 may be initiated by an e-prescribing application with direct access to the switch 114 or through the management module via the Internet 115 .
In a step 207 , the pharmacy module 103 receives the sample code and electronic prescription, triggering any number of actions. If the electronic prescribing switch 114 has accessed the appropriate PBM prior to delivery of the sample code and prescription to the pharmacy module 103 , than the pharmacy may dispense the sample and complete a dispensing confirmation to send to the PBM. If the PBM has not yet been accessed, the pharmacy module 103 instructs a pharmacy's practice management system, which may or may not be part of the pharmacy module 103 , to send the prescription to the appropriate PBM for adjudication. In general, in the step 208 , the SPS 100 preferably coordinates with a pharmacy benefit manager verification that the sample prescription is valid (e.g. not forged), authenticates that the prescription originated from the management module 104 and determines whether or not the sample prescription is likely to cause an adverse reaction with other medications taken by the patient. In one embodiment, the pharmacy module 103 receives the prescription in the form of an encrypted email or faxed sample prescription having a bar code.
In a step, 209 , the pharmacy module 103 transmits sample prescription information to the management module 104 via the PBM. In a preferred embodiment, the pharmacy module 103 may automatically transmit the desired information when the sample prescription is delivered to the patient as an additional transmission. For example, the pharmacy module 103 may produce a bar code (e.g., print a bar code label via a printer 117 ) that is affixed to a package (e.g., container) of the sample prescription. Desirably, the bar code corresponds to the sample code. Thus, a pharmacy employee scans the bar code with a bar code scanner 118 when a patient picks up the prescription. The pharmacy module 103 recognizes the bar code and automatically updates the management module database 112 with additional sample prescription information, such as the date and time the patent picked up the sample prescription. Alternatively, instead of using a bar code and bar code scanner, the pharmacy employee may enter a prescription identification number that corresponds to the sample code into the pharmacy module 103 . This allows for the collection of data specific to the patient receipt of the sample, as adjudication through the PBM is often asynchronous to the time of pickup by a patient. A similar process integrating shipment delivery data may be used to support the collection of the data for prescriptions received at home by a patient.
It is desired that the pharmacy module 103 assist in reporting information about the sample code and the patient by interacting with a designated PBM. Typically, the PBM functions to manage eligibility, conduct utilization reviews for appropriateness of a therapy, and perform settlements between pharmacies, pharmaceutical companies and insurance companies. In this embodiment the PBM also is a primary conduit for the collection of data that is ultimately added to the USPC.
In step 209 , the sample prescription information collected by the PBM is delivered back to the SPS 100 for addition to the code's file in the database 112 . The PBM or the electronic prescription switch 114 may be used to analyze drug interactions between medications prescribed to patients.
In an embodiment, the pharmacy modules 103 have “keys” that enable the pharmacy module 103 to read the sample prescription submitted by the management module 104 . If the pharmacy module 103 does not have the appropriate key, then the pharmacy module 103 cannot open the sample prescription. Also, the pharmacy module 103 may be given a unique pharmacy identifier. When the sample code is sent to the pharmacy module 103 , the unique pharmacy identifier is automatically sent to the management module 104 . If the pharmacy identifier matches pharmacy information populated in the corresponding sample code file (step 204 ), then the management module sends a “key” code to the pharmacy module 103 that enables the pharmacy module 103 to open the sample prescription. This is independent of verifications made on an electronic prescription by the electronic prescribing switch 114 or a PBM. Regardless of the pharmacy module's 103 ability to open a sample prescription, it is still able to adjudicate the sample with a PBM assuming the pharmacy has received an electronic prescription for the sample. The PBM receives the code information ahead of the transaction and is able to verify if the submitted transaction matches the parameters in the code. In this instance the PBM still receives all of the necessary information on the dispensing of the sample to appropriately update the sample code and files in the database 112 .
Advantageously, the sample prescription need not be prepackaged in sample packets, as is commonly the case in current sample prescription allocation methods. Instead, the pharmacy may fill the sample prescription in a similar method as it would with a non-sample prescription, with an exception that the sample prescription is likely a smaller quantity of medication. Thus, the SPS process saves companies the expense of producing the sample prescription packets and also eliminates the cumbersome manual transfer by the pharmacist of media (e.g. paper vouchers or magnetic strip cards) that may represent samples and provides an automatic fully electronic process to complete the transaction. It is also contemplated that the pharmaceutical company reimburse the pharmacy for any costs incurred in filling the sample prescription, which is adjudicated electronically via a third party (e.g., a third party PBM).
In a step 210 , the subscribing pharmaceutical company, having the pharmaceutical module 102 , obtains sample prescription information. In general, the pharmaceutical company purchases information from the management module 104 , which was acquired for the sample codes that were allotted to the pharmaceutical company in the step 200 . In an embodiment, the pharmaceutical company accesses the management module web site via the pharmaceutical module 102 and navigates through the web site to a data report application. Here, the pharmaceutical company can download information stored in the database 111 after paying a fee to the management module entity. In another embodiment, the pharmaceutical company or other subscribing company is provided with a unique identification number, after paying a fee, that allows them to access the sample code files. Preferably, the pharmaceutical company has access limited to only non-confidential information. For example, the pharmaceutical company may be denied access to private patient information, such as social security numbers or names, but has access to non-confidential information such as demographic and metric data. Thus, the pharmaceutical company has access to valuable marketing information, but yet does not violate a patient's confidentiality rights.
Although the present invention has been described in considerable detail with reference to certain preferred embodiments thereof, other versions are possible. For example, one embodiment uses the codes shown in FIG. 3 and a further embodiment uses the sample prescription system process shown in FIG. 4 A-F. Also, many of the steps described herein may be accomplished via mail, fax or other communication method instead of the Internet. Additionally, it is contemplated that the embodiments of the present invention can be used with regular prescriptions as well as sample prescriptions.
Therefore, the spirit and scope of the invention should not be limited to the description of the preferred embodiments contained herein.
|
Systems and methods are disclosed for providing sample prescriptions electronically and creating a complete data set of information regarding the life-cycle of the sample prescription. In one embodiment, a sample prescription system comprises a management module that stores files corresponding to sample prescriptions. Each corresponding file is linked to a unique sample code. The sample code and linked file together comprise an electronic history of the sample's life-cycle, which is built dynamically over time into a comprehensive code containing all information relevant to a prescribed sample and it's path to consumption.
| 6
|
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention describes tubular parts suitable for being used as embeddable electrical boxes, electrical distribution boxes, electrical mechanisms or electrical connection boxes.
[0002] The tubular parts described are characterized by the presence of a rib running across the outer surface of the tubular part through a helical path, and by the presence of support means inside the part for screwing the part into the wall, such as longitudinal channels, for example, suitable for placing screws or other securing means. Additionally, the tubular part is coupled to a receptacle.
BACKGROUND OF THE INVENTION
[0003] In recent years building with prefabricated plaster boards with a paper, cardboard or paint covering has become popular in recent years, such as those marketed under the Pladur® brand, for example. The use of prefabricated boards allows building quickly. Once the inner structure is manufactured, the different water, gas, telecommunications or light installations and their respective outer taps or mechanisms are done.
[0004] In the particular case of electric installations, the state of the art describes different anchoring or embedding systems for electrical mechanisms in the wall. One of the most widely used methods are boxes for the electrical gear which are fixed to the wall by means of through screws and a perforated clamp which adjusts to the thickness of the partition, locking onto the rear portion of the partition.
[0005] These systems have different drawbacks. The process is slow because the operator has to screw in at least two screws for fixing the box to the wall. The box cannot be embedded with its outer portion flush with the wall because the boxes have a support in the transverse direction and projecting outwardly above their side wall of the contour thereof, which support is intended for being supported on the outer surface of the wall and projecting from the front face of the wall.
[0006] The continuous repetition of applying screws can injure operators. For example, if screws are applied by hand, it can cause joint problems. If screws are applied with a machine, the vibrations and noises generated by these machines cause the operator discomfort.
[0007] Patent document ES 241329T3 describes a monoblock box provided with nuts and a screw. Patent document ES 2200284T3 describes an embeddable electrical box without screws, but comprising gripping pins associated with a lever with notching means, where the construction of the electrical box with the interconnection of several elements increases manufacturing costs. The placement of the screws and of the outer ring is slow, while the use of flanges produces a non-removable fixing.
[0008] The state of the art does not show any fixing system for electrical boxes characterized by the presence of ribs on the outer surface of the box which screw said box directly into the wall.
[0009] The problem solved by the invention is that an electrical connection box is obtained which allows a quicker assembly, installs the electrical boxes flush with the wall, improves the fixing to the wall, does not cause or reduces injuries in operators, in which the mechanisms and their trim frames are not separated from the wall and having a simple and more cost-effective manufacture.
[0010] The solution found by the inventors is a tubular part that screws directly into the wall. Therefore, a quick fixing is obtained by means of turning using the support means of the inside of the tubular part, without damaging the wall, by increasing the attachment to said wall and without having to use screws or gripping pins.
DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows a perspective view of the tubular part.
[0012] FIG. 2 shows a perspective view of the receptacle.
[0013] FIG. 3 shows a perspective view of the receptacle coupled to the tubular part.
[0014] FIG. 4 shows the tightening part.
[0015] FIG. 5 shows a section of the tubular part.
[0016] FIG. 6 shows a tubular part with serrated edges.
[0017] FIG. 7 shows the tightening part for a drill.
DESCRIPTION OF THE INVENTION
Definitions
[0018] The term “tubular part” is understood as a hollow conical or cylindrical part.
[0019] The term “receptacle” is understood as a part having a cylindrical or conical section with a base in the lower portion thereof.
[0020] The term “upper portion” corresponds to the portion located in the outer portion of the wall after placing the parts in the wall, i.e., the upper portion of the tubular part corresponds to the outer face of the longitudinal channels in which screws or other securing means are placed and/or where the receptacle is introduced.
[0021] The term “lower portion” corresponds to the portion located in the inner portion of the wall after placing the parts in the wall, i.e., the lower portion corresponds to the face opposite the upper portion, characterized by an inner projection.
[0022] The term “insulating” is understood as any non-conductive material suitable for electrical installations.
[0023] In a first aspect of the invention, the tubular part ( 1 ) comprises on its side surface a rib ( 6 ) projecting from the surface and running along the outer surface of the tubular part through a helical path. The tubular part comprises in the inner portion thereof support means for screwing in.
[0024] The support means can be at least two longitudinal channels ( 3 ) suitable for housing screws or other securing means. FIG. 1 shows the orientation of the tubular part ( 1 ) with four longitudinal channels: the upper portion of the tubular part ( 1 ) corresponds to the area where the screws or other securing means are introduced. The prefabricated plaster wall is perforated with a circular crown drill. The tubular part ( 1 ) is held in the operator's hand by the upper portion thereof, introduced in the wall and screwed in using the support means inside the tubular part. The lower portion of the tubular part ( 1 ) will be located in the inner portion of the wall, while the upper portion of the tubular part ( 1 ) will be located in the outer face of the wall. The rib ( 6 ) allows, by means of the turns made with the aid of the support means, the tubular part to be completely embedded in the wall, because the rib produces a threaded surface in the wall. In a preferred embodiment, the tubular part ( 1 ) is embedded using two channels ( 3 ) as a support point for making the turn.
[0025] In a preferred embodiment, the tubular part has a serrated edge ( 11 , FIG. 6 ) in the lower portion thereof. The serrated edge allows making holes in the wall directly. To make it easier to perforate the wall, the serrated edge can have metallic elements or diamonds.
[0026] The tubular part ( 1 ) embedded in the wall is suitable for being used as an electrical box or as a support for pictures or paintings, light fixtures, wall fittings, shelves, etc. If the tubular part ( 1 ) is used as an electrical box, screws or other anchoring means for securing the electrical mechanisms, switches, trims, sockets or similar elements are placed in the channels ( 3 ). If the tubular part ( 1 ) is used as a support for other elements, eye bolts, hooks or hook nails are introduced in the channel ( 3 ).
[0027] The tubular part ( 1 ) allows quickly assembling electrical boxes, installing the tubular part ( 1 ) completely flush with the wall and giving them optimal strength. By changing the number of ribs and the length and thickness of the rib ( 6 ), the grip of the tubular part ( 1 ) with the wall could be optimized. FIG. 1 shows for example the tubular part ( 1 ) with a rib ( 6 ) running one and a half turns along the outer surface. Alternatively, the tubular part can have several ribs ( 6 ).
[0028] Once the tubular part ( 1 ) is embedded in the wall, any type of channeling from one side to another of the wall could go through the tubular part.
[0029] In a preferred embodiment, the tubular part ( 1 ) comprises inner projections ( 7 ) in the lower portion thereof, as shown in FIG. 1 . The channels ( 3 ) have a shorter length than the length of the tubular part ( 1 ), creating a rail ( 11 ) as illustrated in FIG. 5 .
[0030] In other preferred embodiments, the tubular part ( 1 ) is coupled to a receptacle ( 2 ), as shown in FIG. 3 . FIG. 2 shows the orientation of the receptacle ( 2 ), where the lower portion corresponds to the base of the receptacle. The base of the receptacle ( 2 ) contains break points ( 4 ) to facilitate the passage of cables. The receptacle ( 2 ) has outer projections ( 5 ) in the upper portion thereof which coincide with the inner projections ( 7 ) present in the lower portion of the tubular part ( 1 ) when the receptacle ( 2 ) is nested in the tubular part ( 1 ), see FIG. 3 .
[0031] The installation of the electrical box when the receptacle ( 2 ) is present follows the following steps: the wall is perforated with a crown drill, the tubular part ( 1 ) is screwed into the wall, being flush with it, raceway ducts or cables are passed through the tubular part, the receptacle ( 2 ) is broken at the break point ( 4 ), raceway ducts or cables are passed through the gaps created by breaking the base of the receptacle, the receptacle ( 2 ) is introduced in the tubular part ( 1 ), the receptacle ( 2 ) is moved inside the tubular part ( 1 ) until the inner projections ( 7 ) of the tubular part come into contact with the outer projections ( 5 ) of the receptacle ( 2 ) and the receptacle is turned for the purpose of fixing it to the tubular part.
[0032] The presence of a channel ( 11 ) allows the receptacle ( 2 ) to turn when it is nested in the tubular part ( 1 ). This turning allows avoiding tension in the cables.
[0033] The advantage of the system with respect to other methods of placing electrical boxes is that it is quicker, easier and improves strength and all the parts can be placed on one side of the wall and the wall does not have to be dismantled for placing the parts.
[0034] After applying a 30 kg force perpendicular to the wall, the tubular part ( 1 ) does not come out of place and the wall is not damaged, but when the same force is applied on a distribution box clamped down with screws, the box comes out of the wall.
[0035] Given that the receptacle ( 2 ) is nested in the tubular part ( 1 ) as shown in FIG. 3 , the volume of the receptacle/tubular part assembly is equal to the volume of the tubular part ( 1 ), thereby reducing volumes during transport. Furthermore, the stowed volume of the electrical boxes described in the invention is less than the volumes of the monoblock boxes described in the state of the art, reaching standard measurements once it is assembled.
[0036] The diameter of the tubular part ( 1 ) is comprised between 25 millimeters and 100 millimeters. In a preferred embodiment, the tubular part ( 1 ) has a diameter of 70 millimeters so it can be coupled to the mechanisms and standard drill crowns.
[0037] The part can be screwed into the wall with one hand or with the aid of parts ( 8 , 12 ) of FIGS. 4 and 7 .
[0038] The flat part ( 8 ) contains a rectangular base ( 9 ) the length of which is equal to the inner diameter of the tubular part ( 1 ) and is provided with a surface suitable for gripping with the fingers ( 10 ). The flat part ( 8 ) is introduced inside the tubular part ( 1 ) and the tubular part ( 1 ) is tightened using the support points inside the tubular part.
[0039] The part for a drill ( 12 ) of FIG. 7 is formed by a shank ( 15 ) for being coupled to a drill chuck, and it comprises support means ( 13 ) for the tubular part formed by radial arms and ends in a centering pilot bit ( 14 ) marking and fixing the drilling point. The part ( 12 ) allows effortlessly screwing the parts in more quickly and without having to initially perforate the wall with a crown drill, particularly when the tubular part ( 1 ) has a serrated edge ( 11 ). The part for coupling to the drill needs at least two support points, and to improve the support, the part for a drill ( 12 ) and the tubular part ( 1 ) contain 4 support points as seen in detail in FIG. 7 and FIG. 1 .
[0040] The tubular part ( 1 ), the receptacle ( 2 ) and the flat rectangular part ( 8 ) can be manufactured according to the methods known by the skilled person, for example by injection.
[0041] The described system is primarily suitable for electrical conduits but it can also be used for gas, telecommunication or water conduits.
[0042] The parts described in the invention can be manufactured from any material. If the system is going to be used for electrical boxes, the material must be an insulating material. In a preferred embodiment, the parts are manufactured from PVC or halogen-free thermoplastic ABS material.
[0043] In other aspects, the tubular part described can be used as a support for hanging different objects: pictures or paintings, light fixtures, wall fittings, shelves, etc., furthermore making it easier to house elements or pass them through the wall by changing the diameter of the tubular part ( 1 ). The tubular part ( 1 ) is coupled to the wall and hook nails, eye bolts or hooks are placed in the channels ( 3 ). The attachment by means of the tubular part ( 1 ) prevents damage to the wall and allows hanging heavier objects. The tubular part allows the passage of installations, making connections or housing elements necessary for the light fixtures to operate.
|
The invention relates to a tubular part, an embeddable electrical box and kits formed by both. The tubular part is characterised by a rib that runs helically along its external surface, and by internal support means. The electrical box comprises the tubular part and a cup which fits together with the tubular part and which has break points and external projections. The kits facilitate the assembly of the tubular part and of the electrical box.
| 7
|
FIELD OF THE INVENTION
The present invention relates to the testing of digital circuits and, more particularly, to identifying feedback loops crossing non-scannable memory elements.
SUMMARY OF THE INVENTION
The present invention provides for finding a feedback loop that has no clearing elements. A first node, having a distance count, is employable to record the distance count associated with at least one ancestor node of the first node. There is a loop connecting the first node to a second node. A count analyzer is employable to determine whether the second node, having its own distance count, is the same node as the recorded ancestor of the first node. In one aspect, the loop is flagged as unallowable if the second node is the same node as the ancestor node of the first node.
BACKGROUND
As modern circuit networks shrink in physical dimensions and element counts (transistors, gates, wires) increase exponentially over time, testing a chip for defects after fabrication has become increasingly important and complex. Current state of the art incorporates automated testers which scan computer or hand-generated test cases (known as test vectors) into scan-latches within the circuit network. Generally, scannable memory elements, such as scan-latches, are those elements whose values can be directly observed during a test process. These scannable memory elements are employable to reveal logic values of the circuit blocks under test.
Through employment of known input values, fed into a particular logic function, an output measured by the automated tester can be compared to an expected result. Correspondence of measured results with expected results verifies correct operation of the device.
The physical topology of the circuit network, particularly the arrangement and operation of scannable memory elements, helps to determine the complexity of the test patterns used for verification, the time required for testing each chip, and the quality of those tests in terms of potential faults covered.
Feedback that crosses a particular class of network elements, however, is a physical topology which makes this verification process extremely difficult. Feedback crossing a network element can be generally defined as a feedback loop containing the network element. Feedback across non-scan latches (NSLS)—memory elements whose stored values cannot be directly observed or altered during the test process—pose problems to test pattern generation, test time and test quality.
When a network of logic elements driven by an NSL is fed back to the input of that same NSL, a loop is created that can make testing the circuit networks involved very difficult. Generally, the output value of the NSL at time t n , known as F(t n ), depends on the input F(t n−1 ) because of feedback. F(t n−1 ) in turn depends on F(t n−2 ) in a regression all the way back to the initial state F(0). If this initial state is unknown, testing can be impossible. Even if the initial state is known, however, all values F(0) to F(t n ) (or at a minimum, all the values before some known pattern begins to repeat) should be known by the test pattern generation program in order to determine the next expected output of the circuit network F(t n+1 ). Obtaining and retaining the output values is very costly in terms of compute time and memory, respectively. However, not retaining this information can be even more costly. Not retaining the output values means that the node of logic involved in the loop cannot be tested and, as a result, may have errors that will go unnoticed until use by a customer.
Feedback crossing scannable latches (SLs), however, effectively short-circuits this infinite loop. With SLs, known values can be injected into the circuit network loop at any time and the output can be tested for correspondence to these known inputs. Because it does not pose any special difficulty for test pattern generation, feedback across a scannable element is generally permitted in circuit networks.
A circuit network can be modeled as a directed graph, wherein the nodes or vertices of the graph are the circuit elements (transistors, gates, and so on), while the edges of the graph are the wires, buses or nets of the circuit network. Generally, directed graph is traversed by entering an input pin to the circuit network. A breadth first traversal can be performed from the input. Generally, a breadth first traversal can be defined as visiting and marking all unvisited elements a distance of one from the input, then all unvisited elements a distance of two from the input, and so on. Unvisited elements can generally be defined as a state wherein the element has not yet been visited by the directed graph during a traversal.
However, in the run time of such breadth first traversal algorithms, quadratic O(N 2 ) time is typically required to find feedback cycles in a directed graph. Here, N equals the number of network elements plus the number of wires or nets connecting those elements. With circuit networks where N is in the range of hundreds of millions to billions of elements, this run time is unacceptably slow. Enormous run time in the case of the O(N 2 ) breadth first traversal algorithm means that few, if any, of the detrimental feedback cycles crossing non-scan latches will be detected. This in turn makes the circuit network harder to test, diminishes test coverage and increases test time.
As feedback loops cross non-scannable elements, it is desirable to find and eliminate such loops prior to fabrication. Therefore, what is needed is a feedback detector that overcomes the limitations of conventional feedback detectors.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following Detailed Description taken in conjunction with the accompanying drawings, in which:
FIG. 1A schematically depicts a directed map comprising scannable and non-scannable elements;
FIG. 1B schematically depicts a directed map comprising a hidden feedback loop;
FIG. 2A schematically depicts a circuit network with feedback loops crossing scannable and non-scannable latches;
FIG. 2B schematically depicts the circuit network expressed as a directed graph;
FIGS. 3A and 3B illustrate a method for checking for illegal feedback loops;
FIG. 4 schematically depicts two coupled networks;
FIG. 5A illustrates pseudo-code for a BFS traversal; and
FIG. 5B illustrates pseudo-code for a DFS traversal.
DETAILED DESCRIPTION
In the following discussion, numerous specific details are set forth to provide a thorough understanding of the present invention. However, those skilled in the art will appreciate that the present invention may be practiced without such specific details. In other instances, well-known elements have been illustrated in schematic or block diagram form in order not to obscure the present invention in unnecessary detail. Additionally, for the most part, details concerning network communications, electro-magnetic signaling techniques, and the like, have been omitted inasmuch as such details are not considered necessary to obtain a complete understanding of the present invention, and are considered to be within the understanding of persons of ordinary skill in the relevant art.
It is further noted that, unless indicated otherwise, all functions described herein may be performed in either hardware or software, or some combination thereof. In a preferred embodiment, however, the functions are performed by a processor, such as a computer or an electronic data processor, in accordance with code, such as computer program code, software, and/or integrated circuits that are coded to perform such functions, unless indicated otherwise.
Turning to FIG. 1A , disclosed is a directed map of circuit network 100 comprising scannable, or “clearing,” elements 110 and non-scannable, or “non-clearing,” elements 120 . Generally, the network 100 is tested for non-allowable feedback loops between different logic blocks.
In one embodiment, the scannable and non-scannable elements 110 , 120 are pairs of flip-flops. In the network 100 , clearing elements, such as scan latches 110 , are interposed in electrical paths through the circuit network 100 . FIG. 1 further comprises logic blocks 115 , 125 and 135 . Generally, a node comprises circuit network elements, such as memory elements, logic gates and logic blocks.
The network 100 further comprises a distance incrementer 117 , an attribute assignor 119 and a count analyzer 122 within a feedback detector engine 116 . Generally, the distance incrementer 117 increments a count associated with a node when traversing from node to node or from node to non-scannable flip-flop. For instance, the count is incremented by one when traversing from node 125 to non-scannable element 120 . In one embodiment, the count set by the distance incrementer 117 is reset to zero when encountering a scannable element. For example, when traversing from node 115 to scannable element 110 , the count is reset to zero.
In the network 100 , feedback lines can cross either clearing elements or non-clearing elements. Turning briefly to FIG. 2A , disclosed is a network 200 with feedback crossing clearing and non-clearing elements. Turning back to FIG. 1 , typically, feedback lines are allowed in the circuit network 200 if they cross a clearing element. However, there are design constraints if the feedback loop crosses non-clearing elements. Generally, denoting clearing and non-clearing elements in the circuit network 100 allows for detection of unallowable feedback loops. Generally, feedback loops which cross scan-latches 110 are allowed. Feedback cycles which cross only non-scan latches 120 are not allowed.
In the circuit 100 , these clearing elements are placed a maximum distance D from the last clearing element and a maximum distance D from the circuit network input pins. The parameter D is generally defined by design criteria. For example, a maximum of D=30 logic blocks are allowed to be interposed between scan latches. If a feedback loop contains a clearing element, and meets the design criteria, then the feedback loop is allowable. If a feedback loop does not contain the clearing element within the specified parameter D, then the feedback loop is unacceptable.
In FIG. 1A , for each node 115 in the network 100 , graph information is stored by an attribute assignor 119 .
The network 100 is tested for unacceptable feedback loops through employment of a traversal of the network 100 . When traversing the network 100 from input to output, the logic blocks 115 have one of their attributes assigned to them by the attribute assignor 119 . In one embodiment, these attributes are color-coded.
TABLE 1
Information for Breadth First Traversal
Characteristic
Description
Attribute
First, Second or Third
(Color)
(RED, GREEN, or BLACK)
Distance
The distance away from the last
clearing element if the color of this node
115 is GREEN or RED, or the distance away
from the input if the color of this node 115
is BLACK. (“DIST”).
Predecessor
The unique element from which the
directed map first reached this logic block.
Also known as the parent element. By
definition, a parent element is a distance
of 1 away from its children.
Nodes inherit the color of their predecessor node except for the following initial and special conditions. In one embodiment, the attribute assignor 119 performs the attribute assignment of inheritance. Nodes are assigned a first attribute by the attribute assignor 119 when they are first traversed as an input to the circuit network 100 . In one embodiment, the first attribute is the color BLACK. Nodes are assigned a second attribute by the attribute assignor 119 , after a path passes through a clearing element 110 , such as a scan latch between a parent node and a child logic block. In one embodiment, the second attribute is the color GREEN. Nodes are assigned a third attribute after a traversal crosses a non-clearing element. In one embodiment, the third attribute is the color RED.
The distance characteristic DIST associated with each element is incremented by the distance incrementer 117 with each node 115 or a non-scannable element 120 of the network 100 from a starting point of zero at the input. The increment occurs with each traversal of a node except after passing through a clearing element 110 , whereupon the distance is reset to zero by the distance incrementer 117 . Hence, the distance characteristic DIST associated with each node 115 measures the distance to the last clearing element 110 , if the node 115 color is RED or GREEN. The distance characteristic DIST also measures distance to the input, if the node 115 color is BLACK. If this distance characteristic DIST ever exceeds the predetermined constant value D, set by the architectural design criteria, a design violation occurs.
In FIG. 1A , feedback cycles across logic blocks 115 have design restraints. Again, feedback loops which cross logic element paths having scan latches 110 are allowed, if they meet the other design criteria. Feedback cycles which cross only non-scan latches are not allowed.
In FIG. 1A , logic blocks 115 are previously visited if they have the first, second or third attribute. In traversing a directed graph of the network 100 , encountering a first node from a second node can indicate a feedback line, or it can denote the convergence of two paths. The test is then performed by the count analyzer 122 .
For instance, if the attribute color associated with an originating, or first logic element, is GREEN, a potential feedback loop, to a potential predecessor second node, is automatically permitted. The count analyzer 122 performs no further testing of this loop and flags it as an allowable connection. This is because feedback originating from a GREEN node would necessarily cross a scannable element 110 . Therefore, determining whether the second node is a predecessor of the first node is not necessary and the operation completes in constant time. This type of scannable element 110 is known as a “clearing element” because after passing through it, the DIST characteristic is reset to zero by the distance incrementer 117 . A check for feedback within its cleared, or GREEN, zone is not necessary.
However, if the second, or intersected, node has the third, or RED, attribute, an illegal feedback loop could be present. An illegal feedback loop is detected by the count analyzer 122 if the second node that the first node intersects is a predecessor of the current logic block, and if there is no scannable element between the first node and the second node that would make the feedback legal.
In order to determine if an illegal feedback cycle has been found, the count analyzer 122 traverses the list of predecessors of the first, or generating, node back to the distance corresponding to the intersected second node. If the second node is an ancestor of the first node, then an illegal feedback loop has occurred. If the ancestor having the same DIST value is not the second node, an illegal feedback loop has not occurred, and the count analyzer 122 flags an allowable feedback loop. In other words, by the count analyzer 122 enquiring to, at most, the last scannable element 110 , but not beyond it, it can be discovered that no scannable element 110 exists between the first node and the second node that would make the feedback allowable. If feedback is not allowable, then the design can be altered to either eliminate the feedback loop or make it allowable by inserting a scannable element.
Following is pseudo-code to ensure that a predecessor logic element 115 contains or does not contain a scannable element.
CurrNode = Y
WHILE Distance[CurrNode] > Distance[X] DO
# Iterate back through predecessor list
CurrNode = Predecessor[CurrNode]
OD
# Distance[CurrNode] = = Distance[X]
IF CurrNode = = X THEN
RETURN FeedbackCycleFound
FI
RETURN FeedbackCycleNotFound
As is understood by those of skill in the art, OD represents closing the statement that is started with DO, in a similar manner to FI closing a statement starting with IF.
Since the distance characteristic DIST measures the distance away from the last clearing element 110 or the initial input, and this distance can be, at most, a constant distance D away, the above operation takes O(D) constant time. That is, at most, D predecessors will be queried to determine if that predecessor matches the requested DIST value of the intersected node X. Run time depends upon the design criteria which set D at a constant value. For example, there can be no more than D=30 logic gates between scan latches.
When the search for a particular input is complete, the attribute assignor 119 and the distance incrementer 117 are applied to the next input pin to the circuit network, and so on, until all of the inputs to the network are traversed. Distance, color and predecessor characteristics are retained on node 115 elements during this process. That is, nodes 115 that were visited and assigned an attribute during the traversal on one input pin will still remain colored via the previous traversal on the traversal of the next input pin.
Turning now to FIG. 1B , disclosed is a hidden feedback loop. In the case of two converging paths of different colors (such as the attributes of GREEN and RED or BLACK and RED), the BFS traversal could proceed in a way that hides feedback crossing an NSL. Typically, this occurs only when a RED path and a non-RED path converge at an element. Whichever path reached the node first will color it and be listed as the predecessor.
In FIG. 1B , DIST=distance as measured by the BFS. The top path reaches node P at DIST=2 and colors it GREEN. Since node P is GREEN, the algorithm does not check output leading to the BLACK node at distance 1 as a potential feedback. Therefore, the BFS determines there is no unallowable feedback loop from P with respect to the top path. However, there could be an unallowable feedback loop with respect to another path leading to node P if that other path is RED. When the bottom path reaches node P, RED dominates the converging paths and is propagated through. This allows for the detection of any illegal feedback from nodes P and beyond leading back to the bottom path.
Since the RED path dominates GREEN and BLACK, each path in the network is traversed, at most, twice; once when coloring GREEN or BLACK, and then potentially a second time if RED dominates a converging path. Hence, the overall run time 2*n=O(n) stays linear.
Turning again to FIG. 2A , illustrated is a circuit network 200 with feedback loops crossing scannable and non-scannable latches. The network 200 comprises inputs IN 0 , IN 1 and IN 2 . The IN 0 is input into AND gate 210 . The output of AND gate 210 is input into a scannable latch (SL 1 ) 220 and a non-scannable latch (NSL 1 ) 230 . The NSL output is then fed into a 2-way AND gate 231 . The output of the 2-way AND gate is fed into an input of the AND gate 210 , thereby creating a feedback loop. The output of the scannable latch 220 is inverted by the inverter 225 . The output of the inverter 225 is input into a scan latch 235 and a non-scannable latch 237 . The output of scan latch 235 and the non-scannable latch 237 are OUT 0 and OUT 1 , respectively. The output of inverter 225 is also fed into an input of the 3-way AND gate 210 , thereby creating another feedback loop.
IN 1 and IN 2 are input into two signal buffers 240 and 241 , respectively. The buffers are then fed into a 3-way AND gate 242 . The output of the AND gate 242 is fed into a scannable latch 244 . The output of the scannable latch 244 is fed into a 2-way AND gate 246 . The output of AND gate 246 is fed into the 2-way input AND gate 231 , and also fed into NSL 3 248 . The output of NSL 248 is input into the 3-way AND gate 242 , thereby creating a feedback loop. Furthermore, the output of NSL 248 is input into the AND gate 246 , thereby creating another feedback loop. Finally, the output of NSL 248 is also fed to OUT 2 .
Turning now to FIG. 2B , illustrated is the network 200 of FIG. 2A expressed as a directed graph 270 . For purposes of illustration, the various nodes of the directed graph 270 have been expressed as a first, second and third attribute, such as RED, GREEN and BLACK, but those of skill in the art understand that other coloring schemes are within the scope of the present invention.
When testing for feedback loops that violate design parameters, the directed graph 270 is characterized. Starting at IN 0 , the node “a,” corresponding to a node 115 , is colored “BLACK,” as it has not intersected an SL or non-SL latch. The DIST count at node “a” is 1. Then, each path 211 and 212 is traversed in the next round of the BFS, which looks at elements a distance of two away from IN 0 , and memory elements, such as latches, are encountered. SL ( 220 ) is scannable, so it is colored GREEN. Furthermore, the distance variable is set back to zero. However, path 212 encounters a non-scannable latch NSL ( 230 ), so a color transition is made from BLACK to RED, and the Distance variable is incremented and stored in the non-scannable latch. SL 220 is then traversed to node “b” which is GREEN due to the GREENness of its immediate predecessor, and the Distance variable for this node is incremented to “1.” NSL 230 is then traversed into node “c.” Node “c” is RED due to the REDness of its immediate predecessor, and its associated Distance is incremented to “2.”
The output of node “b” is then in a feedback loop to node “a.” Because the color of NSL 3 is RED, a check is performed to determine whether a scannable element exists between the NSL 3 and the nodes “e” and “f” which are found to have already been visited. It is determined that “f” having DIST count 1, is the ancestor of NL 3 having DIST count 1. Therefore, the feedback loop to node “f” is not allowable. It is determined that “e” having DIST count 2 is not the ancestor of NSL 3 having DIST count 2. For this reason, there is a scannable element between NSL 3 and node “e.” Indeed, SL 3 is between NSL 3 and node “e,” so the feedback is allowable. Furthermore, in FIG. 2B , the distance is within the allowable design constraint D, so the second design feature is met. Therefore, feedback loop 213 is allowable.
In FIG. 2B , because node “a” already has an associated attribute, node “c” checks to see whether an ancestor node that has the same distance count, before the last scannable element, is the same as the intersected node. In the illustrated embodiment of FIG. 2B , node “a” is the same node as the predecessor node having the same distance count, so the feedback is illegal.
Starting from input IN 1 and IN 2 , the input nodes “d” and “g” are both BLACK. They are, in turn, traversed into node “e,” which also inherits the color attribute, in this case BLACK, from its immediate predecessor. The output of BLACK is then fed into SL 3 ( 244 ), which resets the count to zero and changes the inheritable attribute to the second attribute, GREEN. This second, or GREEN, attribute is inherited by node “f.” The output of node “f” is input into node “c” and NSL 3 .
Because node “f,” the originating node, has the second attribute, any feedback that occurs between node “f” and node “c” is an allowable feedback. However, node “f” is also input into NSL 3 , thereby changing the color from GREEN to RED from this element and after. The output of RED is then fed into the node “e.”
Because the color input into node “e” is RED, a check is performed to determine whether a scannable element exists between the NSL 3 and the node “e.” It is then determined whether or not a node “e,” having its associated distance count, is the same node as the ancestor node of NSL 244 . These two nodes are not the same, so this is a legal loop.
In a further embodiment, it is determined whether the total number of logic elements between scannable elements exceeds D. This is typically performed as part of the same traversal as determining for an illegal feedback loop. In one embodiment, this is performed by determining if the DIST value for the tested node is greater than the D allowable value.
In a further embodiment, combinational logic feedback loops are discovered. Combinational logic loops are detrimental to chip testing for similar reasons that non-scan latch feedback loops are. A combinatorial logic loop can be generally defined as a logic loop where the loop does not involve any memory elements. Typically, combinational logic loops create infinite loops whose values cannot be directly observed or altered by the test equipment.
In one embodiment, to find combinational logic loops, the predecessor list is examined up to the value of DIST of the intersected node, regardless of the color of the source node. If the source node identifies the intersection node as a predecessor, then this loop is either a combinational logic loop or an illegal NSL feedback loop. Either way, the feedback loop is identified and reported for correction. The testing for a single combinatorial logic loop is O(D) constant time. The run time of this new method to find all such loops is O(D*N)=O(N), where D is a constant value independent of N, where N is equal to the number vertices (nodes) plus the number of edges (arcs) in a directed graph representation of the circuit network. Equivalently, this is the number of circuit elements plus the number of interconnections between those elements.
Turning now to FIGS. 3A and 3B , illustrated is a method 300 for checking for illegal feedback loops in a circuit network using a BFS algorithm. In step 301 , the method starts. In step 302 , an input of the circuit network is entered. In step 305 , distance count (DIST) is set to zero. Generally, distance count at a node is the path length from that node back to the last scannable element. In step 307 , a default attribute is set to the third attribute. In one embodiment, the third attribute comprises the color BLACK.
In step 310 , there is an increment from either an input or a parent node to a child node. In other words, the next child node for the BFS traversal is examined. In step 314 , the method 300 determines whether the child node has been visited before. In one embodiment, this is performed through determining whether the child node has a first, second or third attribute assigned to it. In other words, if the child node has any of the RED, GREEN or BLACK colors assigned to it.
If the child node has been visited before, in step 320 , the method 300 determines whether the intersected node is RED. If the intersected node is RED, then the DIST value of the intersected node is determined in step 322 . Then, in step 325 , the parent/originating node predecessors are traversed to the same DIST as the intersected node in step 330 . In step 340 , the method 300 determines whether the intersected node is the same node as the node having the same DIST value in the predecessor list. If it is, then the feedback is unacceptable, and the method stops in step 345 . However, if the two nodes are not the same, the feedback is determined to be allowable in step 347 .
However, if the intersected node is determined not to be RED in step 320 , the method 300 determines if the parent node is RED in step 330 . If the parent node is not RED, then step 347 executes, and feedback is allowable. However, if the parent node is RED, then step 362 executes, and the color of the intersected node is set to the third attribute (RED).
If step 314 determines that the child node does not have an attribute of RED, GREEN or BLACK associated with it, that child node has not been visited before, and step 350 executes. Step 350 determines whether the child node is a memory element and, if so, whether it is a scannable memory element. If the child node is a scannable memory element, then the second attribute (GREEN) is set for the child node, in step 361 . Then, the DIST count is reset to zero in step 364 . If the child node is a non-scannable memory element, then the third attribute (RED) is set for the child node, in step 362 . If the child node of step 350 is not a memory element, the child node inherits its color from the parent node, in step 363 . In either case of step 362 or step 363 , the child DIST is set to equal the parent DIST+1 in step 365 . In either the case of step 364 or step 365 , in step 370 , the parent node indicia (that is, the first second or third attribute) is stored in the predecessor attribute of the child node, such as a pointer to the parent node in the child node's predecessor attribute. Typically, one such value is stored per node.
After either step 347 or step 370 executes, the method 300 then determines whether a parent node has any other child nodes to look at, in step 375 . If there are more child nodes to look at, step 310 re-executes, and the next child node is looked at. If not, in step 380 , the method 300 determines if there are any more nodes left to test. If there are more nodes to test for illegal feedback, then in step 382 , the BFS moves to the next node. Determination of the next node is implementation specific. In general, each node stores a list of pointers to its children. Once done iterating through this list of children, the next node can be obtained by popping the top element off a queue, and step 310 re-executes. If there are no nodes to be tested, then in step 385 , it is determined whether there are any more inputs to the circuit network. If there are more inputs, then the new input is entered again in step 302 , and the flow re-executes. If not, then in step 390 , the method indicates that it is done, and exits the program.
In a further embodiment, a depth first traversal is performed from an input to the circuit network. Depth first searches (DFS) go to the end of a given path before returning to go to the end of the next path. The attributes of the DFS are as follows.
TABLE 2
DEPTH FIRST EMBODIMENT
Characteristic
Description
Attribute
First, Second or Third
(Color)
(RED, GREEN, or BLACK)
Distance
The distance away from the last
clearing element if the color of this node
115 is GREEN or RED, or the distance away
from the input if the color of this node 115
is BLACK.
Predecessor
The unique element from which the
directed map first reached this logic block.
Also known as the parent element. By
definition, a parent element is a distance
of 1 away from its children
The unique ID assigned to the last
scannable latch encountered on the path
leading to this node.
Status
NULL/NOT — VISITED,
NOT — FINISHED,
FINISHED.
ZONE — ID
The unique element from which the
directed map first reached this logic block.
Also known as the parent element. By
definition, a parent element is a distance
of 1 away from its children.
The distance, predecessor and color attributes of the BFS of Table 1 substantially correspond to the DFS of Table 2. However, DFS have two additional characteristics. These are the “status” attribute and the “ZONE — ID” attribute.
Before being encountered in an attribute-assigning traversal, each node has the status of NULL/NOT VISITED. When first visited, a node is designated as NOT — FINISHED. A node is not marked FINISHED until all of its children nodes have completed their depth first traversals.
The ZONE — ID is a unique ID assigned to the last scannable latch seen on the path leading to a logic block. After passing through a scannable latch (SL), the logic blocks on the subsequent paths are inside the given zone until the paths pass through a different SL.
If during traversal a first node runs into a second node that already has an attribute associated therewith, it can be determined if the second node is a predecessor through reading the status of the second node. If the status of the second node equals NOT — FINISHED, then the second node is a predecessor and feedback has been found. To determine whether this is an illegal or permissible feedback loop, the ZONE — ID of the first and second nodes are compared. If the ZONE — ID of the second node is equal to the ZONE — ID for the first node, then a feedback loop which does not cross any scannable element has been found. Therefore, this feedback is not allowed (that is, it is illegal).
If the ZONE — ID for the second node is not equal to the ZONE — ID of the first node, there is a scannable element between the first and second node, and feedback is allowed. This follows from the definition of the ZONE — ID. This definition is that nodes along all paths originating from a scannable element inherit that scannable element's ZONE — ID. This continues until those paths pass through a different scannable element wherein the nodes will obtain a different ZONE — ID.
DFS and BFS are two fundamental and widely used ways to traverse graphs. By providing methods for detecting feedback crossing only NSLs using both traversals, the invention can more easily be integrated into existing microelectronics design tools and methodologies.
Whether DFS or BFS is used is implementation specific and may depend on some knowledge of the circuit network. For example, a circuit network with wide fan out relative to its depth would require a large BFS queue and a relatively small DFS stack. Conversely, a circuit network with low fan out and long relative depth would require a larger DFS stack than a BFS queue. This can be important if system memory is a limiting bottleneck.
Turning now to FIG. 4 , illustrated are two networks 410 and 420 . Large integrated circuit designs, including system-on-a-chip designs, can consist of many interconnected modules, or networks. In FIG. 4 , the networks 410 and 420 , each free of illegal NSL feedback loops, form an illegal NSL feedback loop when connected.
To avoid such problems, in a further embodiment, when networks 410 and 420 are verified to be free of detrimental feedback loops across NSLs, the resulting aggregate circuit network is also verified to be free of boundary violations. This can be enforced through the following boundary rules.
1) A scannable element is reached on any input path before a non-scannable element is reached. This is the “input” rule. 2) A scannable element is the last latch seen on an output path. This is the “output” rule. In other words, a non-scannable element cannot be seen last (that is, after a scannable element). 3) Finally, a latch is to be seen at some point on the path before being output. The is the “latch” rule.
If both the input and output rules are employed in the design of the plurality of networks 410 and 420 , a feedback loop will not cross only an NSL when networks 410 and 420 are connected. Generally, if either the input or output rules are applied, along with the latch rule, there cannot be any NSLs between the output of a first module and its connection to the input of a second module, and hence no illegal feedback loops are possible.
In this further embodiment, at least some of the boundary latches, such as 235 , 237 and 248 are scannable between every large functional unit, such as networks 200 are scannable. This means that at least the first latch traversed along any input path, such as latches 220 , 230 , and 244 , are scannable. In a further embodiment, the last latch seen on any output, such as latches 235 , 237 and 248 , are scannable. In a still further embodiment, scan latches may be placed as both the first input and last output latches. This configuration allows control over the inputs of the network 200 and observation of all outputs to match with the expected results. Any one of these three boundary scan embodiments, if employed within a plurality of aggregated networks 200 , will ensure that no feedback loops crossing only NSLs can exist between network 200 . FIG. 3 indicates how this could happen. If only the output rule is applied, this again is sufficient to guarantee no feedback loops crossing only NSLs can occur when networks 410 and 420 are connected, provided the latch rule is applied.
To enforce the boundary rules, it is necessary to ensure that, for the input rule, there is no color transition from the first attribute to the third attribute, for example, from BLACK to RED. Such a transition indicates that a non-clearing element was seen before a clearing element on an input path, which is not allowed under the input rule. To enforce the output rule, the attribute color of the last node (the node connected to the output pin) is not RED, the third attribute. If the attribute color is RED, then the last latch seen on the output path was not scannable. For the latch rule to be enforced, the color of the last node must be GREEN or RED. This ensures that the input to output path has a latch on it.
Those of skill in the art understand, however, that discovering illegal feedback loops can apply to communication networks, power networks, computer networks, control networks, and so on. In other words, the present invention can be applied to networks having feedback present within.
Turning now to FIGS. 5A and 5B , disclosed are source and pseudo-code for a BFS and DFS implementation, respectively, of the methods described in this invention. Input and output boundary checking is performed. Design criteria validation is also performed. This ensures that the distance between non-scan latches never exceeds the predetermined value D=MAX — DIST.
In FIG. 5A , the procedure Find — All — Feedback( ) is called on the directed graph representation of the circuit network. From there, a breadth first search (BFS) traverses the graph looking for feedback loops. All feedback loops crossing only non-scan latches are found in linear O(N) time. N=|V|+|E|, the number of nodes plus the number of edges or, equivalently, the number of circuit elements plus the number of interconnects/wires between them. In a further embodiment of FIG. 5B , a depth search (DFS) traverses the graph looking for feedback loops.
It is understood that the present invention can take many forms and embodiments. Accordingly, several variations may be made in the foregoing without departing from the spirit or the scope of the invention. For example, different communications standards may be implemented, and the like.
Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered obvious and desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.
|
All feedback cycles in a circuit network which cross only non-scannable memory elements are detected in linear run time. The method models a circuit network as a directed graph, then attributes network elements so that a single feedback cycle may be found in constant time. In the breadth first version, feedback is detected by traversing at most a constant distance back to the last scannable memory element. In the depth first version, graph nodes are not FINISHED until all predecessors are FINISHED. Feedback is found immediately if a node runs into another node that is NOT — FINISHED. This feedback is illegal if both nodes are in a zone defined by the same scannable memory element. The resulting identification and removal of feedback loops crossing only non-scannable memory elements significantly reduces the subsequent complexity of test pattern generation. This ensures a faster, more reliable, and more accurate test process after circuit fabrication.
| 6
|
TECHNICAL FIELD
The present invention relates to a method of compiling an image database, an image database compilation program, and an image retrieval method. More specifically, the present invention relates to a method of compiling an image database used for specific object recognition using local features, a program for causing a computer to execute the method of compilation, and an image retrieval method using the image database.
BACKGROUND ART
Specific object recognition is processing of determining which, among objects in other images, an object taken as an image is identical to. As used herein, this processing is also referred to as image recognition. For example, such processing can be used for detection of excess or deficiency of parts, detection of counterfeits or the like, or substitute for bar-code processing, thus having a high utility. Here, “an object taken as an image” means an instance (retrieval target) included in the image as a query, and “processing of determining which, among objects in other images, an object taken as an image is identical to” is also understood as processing of retrieving an image including an identical instance from an image database in which multiple images have been registered in advance, that is, processing of image retrieval.
A method using local features is known as one of methods of the specific object recognition. In the method using local features, an image is represented by local features extracted from the image through a predetermined procedure, and the local features are compared or matched with local features extracted from another image, whereby identification (recognition) is performed. For example, local features are used in SIFT (Scale-Invariant Feature Transform) (for example, see Non-Patent Literature 1) and PCA-SIFT (Principal Component Analysis-SIFT) (for example, see Non-Patent Literature 2). Such a local feature is represented as a multidimensional vector, and therefore, is also referred to as a feature vector. The above methods have a merit that recognition with a high accuracy can be performed even when there is some occlusion or variation in an instance included in a query image and/or an instance included in an image registered in an image database, because multiple feature vectors are extracted based on local characteristics of an image.
Other literatures relevant to the present invention include Non-Patent Literatures 3, 4, and 5. Specific relevancy between the present invention and each of the literatures will be described later.
CITATION LIST
Non-Patent Literature
Non-Patent Literature 1: D. G. Lowe, “Distinctive image features from scale-invariant keypoints”, Internal Journal of Computer Vision, 60, 2, pp. 91-110, 2004.
Non-Patent Literature 2: Y. Ke, and R. Sukthankar, “PCA-SIFT: A more distinctive representation for local image descriptors”, Proc. CVPR' 04, vol. 2, pp. 506-513, 2004.
Non-Patent Literature 3: Noguchi, Kise, and Iwamura: “Experimental Study of Memory Reduction for Object Recognition based on Local Descriptors”, Collection of papers in Meeting on image recognition and understanding (MIRU 2008), OS 10-3, pp. 251-258, 2008.
Non-Patent Literature 4: D. Nister and H. Stewenius, “Scalable Recognition with a Vocabulary Tree”, Proc. CVPR 2006, pp. 775-781, 2006.
Non-Patent Literature 5: S. Arya, D. Mount, R. Silverman and A. Y. Wu, “An optimal algorithm for approximate nearest neighbor searching”, Journal of the ACM, vol. 45, no. 6, pp. 891-923, 1998.
SUMMARY OF THE INVENTION
Disclosure of the Invention
The number of local features extracted from one image is, if the image has a size of VGA, normally, about several thousand, or it can sometimes be several tens of thousand. Therefore, in the case where the sizes or the number of images to be recognized are large, processing time needed for comparing local features of the images, and a memory amount needed for storing the local features become problems.
In order to solve the above problems, an approach that a memory amount needed for storing each local feature is reduced has been proposed (see Non-Patent Literature 3). Specifically, scalar quantization which reduces the bit number of multivalued data representing the values of the dimensions of each feature vector, is performed to reduce a memory amount needed for registering each local feature into an image database, whereby a memory amount needed for the entirety of the image database is reduced. This method has a merit that scalar quantization can be performed in a relatively easy manner by investigating the distribution of the values of the dimensions of each feature vector in advance. Meanwhile, a concept of vector quantization has been also proposed. D. Nister, et al., have proposed a method using a tree structure called Vocabulary Tree, as one of methods of vector quantization (for example, see Non-Patent Literature 4). However, in this method, the height of the tree structure needs to be increased to maintain a high recognition rate. Therefore, there is a problem that a sufficient effect of reducing a memory amount cannot be expected.
The present invention has been made in light of the above context, and provides a method for, in a method of performing object recognition by means of near neighbor search using local features extracted from an image, reducing a memory amount needed for an image database used in the object recognition, without largely decreasing the recognition rate of the object recognition; and a program for causing a computer to execute the method. In addition, the present invention provides a method for retrieving an image using an image database compiled based on the above method.
Solution to the Problems
The present invention provides a method of compiling an image database storing reference images to be compared with a query image and being used for object recognition, the method comprising: an extracting step of extracting a plurality of reference feature vectors representing local features of different locations from a reference image to be stored into the image database, each reference feature vector having a vector length and a vector direction; a clustering step of forming clusters, each cluster being composed of different feature vectors; a selecting step of selecting a feature vector from each cluster as a representative vector of each cluster; and a storing step of storing the representative vector into the image data base in relation with the reference image, wherein: the clustering step forms each cluster so that the reference feature vectors representing local features locating closely on the reference image belong to the same cluster; the selecting step gives a priority to any of the reference feature vectors each having a long vector length to select the representative vector; the comparison is made by generating at least one query feature vector from the query image in the same manner as that of extracting the reference feature vector and adopting a near neighbor search between the query feature vector and the representative vector; and each of the above steps is executed by a computer.
In another aspect, the present invention provides an image database compilation program for causing a computer to execute a compilation of an image database storing reference images to be made comparison with an query image and being used for object recognition, the program comprising: an extracting step of extracting a plurality of reference feature vectors representing local features of different locations from a reference image to be stored into the image database, each reference feature vector having a vector length and a vector direction; a clustering step of forming clusters, each cluster being composed of different feature vectors; a selecting step of selecting a feature vector from each cluster as representative vector of each cluster; and a storing step of storing the representative vector into the image data base in relation with the reference image, wherein: the clustering step forms each cluster so that the reference feature vectors representing local features locating closely on the reference image belong to the same cluster; the selecting step gives a priority to any of the reference feature vectors each having a long vector length to select the representative vector; and the comparison is made by generating at least one query feature vector from the query image in the same manner as that of extracting the reference feature vector and adopting a near neighbor search between the query feature vector and the representative vector.
In addition, the present invention provides, as a method associated with the above method of compiling the image database, an image retrieval method of retrieving from an image database storing previously a plurality of reference images to be compared with a query image and being used for an image retrieval, each reference image being stored in conjunction with representative vectors extracted from each reference image, a particular reference image corresponding to the query image, the method comprising: an extracting step of extracting at least one query feature vector representing local feature of the query image and having a vector length and a vector direction; a comparing step of making comparison between the query feature vector and the representative vectors related to each reference image adopting a near neighbor search therebetween, wherein: the representative vectors are obtained through a procedure of extracting a plurality of reference feature vectors from each reference image in the same manner as that of extracting the query feature vector; forming clusters, each cluster being composed of the reference feature vectors, so that the reference feature vectors representing local features locating closely on each reference image belong to the same cluster; selecting the representative vector from each cluster giving a priority to any of the reference feature vectors having a long vector length to select the representative vector; and each of the above steps is executed by a computer.
It is noted that a procedure of generating a query feature vector from the query image is the same as the procedure of extracting a feature vector.
Effects of the Invention
In the method of compiling an image database according to the present invention, each cluster is formed so that the reference feature vectors representing local features locating closely on the reference image belong to the same cluster; a priority is given to any of the reference feature vectors each having a long vector length to select a predetermined number of representative vectors from each cluster; and the comparison is made between the representative vectors and the query feature vector. Therefore, it is possible to save a memory amount needed for registering feature vectors into the image database, in comparison with the case where such selection of representative vectors is not performed. In addition, representative vectors selected from the respective clusters are registered, that is, the registration is performed in a substantially uniform manner over the entire area of an image without taking feature vectors only from partial areas of the image. Therefore, even when instances are unevenly included in an image or an image was taken being subject to distortion due to geometrical conversion, it is possible to perform robust recognition.
The program for compiling an image database according to the present invention has the same merit as the above method for compiling an image database.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram for explaining the concept of ANN which is a known method of approximate nearest neighbor search. The ANN is employed as a method of approximate nearest neighbor search in an embodiment of the present invention.
FIGS. 2( a ) to 2 ( c ) show examples of images registered in an image database in experiments of the present invention. FIG. 2( a ) shows examples of images collected by using Google image search. FIG. 2( b ) shows examples of images published on a Web site of PCA-SIFT. FIG. 2( c ) shows examples of images collected on “flick” which is a photograph sharing site.
FIGS. 3( a ) to 3 ( d ) show examples of images used as query images in the experiments of the present invention. FIGS. 3( a ), 3 ( b ), and 3 ( c ) show images obtained by shooting pictures of an instance at shooting angles of 90°, 75°, and 60°, respectively. FIG. 3( d ) shows an example of an image obtained by shooting a part of a picture of the instance.
FIG. 4 is a graph showing a result of an experiment of the present invention. This graph shows recognition rates for query images shown in FIGS. 3( a ) to 3 ( d ), and an average recognition rate of the recognition rates.
DESCRIPTION OF EMBODIMENTS
Hereinafter, preferred embodiments of the present invention will be described.
The clustering step may form a predetermined number of clusters. Even when instances are unevenly distributed in an image or an image was taken being subject to distortion due to geometrical conversion, if the representative vectors are distributed in a substantially uniform manner over the entire area of the image, it is possible to perform robust recognition. The larger the number of clusters to be generated is, the more uniformly the representative vectors are distributed. If the number of clusters that allows sufficiently robust recognition is determined in advance, for example, by experiment, and if the clustering step forms the determined number of clusters, it is possible to perform sufficiently robust recognition.
In addition, the selecting step may determine a sole representative vector from each cluster.
In addition, the clustering step may form the clusters using k-means clustering. Thus, it is possible to cluster feature vectors by k-means clustering such that the representative vectors are evenly distributed over the entire area of the image.
The preferred modes described above may be combined with each other.
Hereinafter, the present invention will be further described in detail with reference to the drawings. It is noted that the following description is in all aspects illustrative. It should not be understood that the following description limits the present invention.
A characteristic aspect of the present invention is to consider reduction of a memory amount for an image database used in image recognition from a viewpoint of sifting selection of local features, and to provide a method for achieving the reduction. More specifically, sifting selection of local features is performed in consideration of the vector lengths (scales) of feature vectors and the uniformity of distribution of the feature vectors in an image space.
According to the following embodiments and experiments, a recognition rate of 98% was obtained even in the case of using an image database for which a memory amount is reduced to about 10% of a memory amount for an image database used in the case where sifting selection of local features is not performed. In this way, the effectiveness of the present invention was verified.
Here, a conventional memory amount reduction method using scalar quantization and the corresponding image recognition processing, performed in specific object recognition, will be once described, before the description of a method for reducing a memory amount according to the present invention. The conventional memory amount reduction method using scalar quantization reduces a memory amount for an image database by an approach different from the method of the present invention. The conventional memory amount reduction method may be combined with the method of the present invention, and it is effective to combine them.
<<Memory Amount Reduction Method using Scalar Quantization>>
Non-Patent Literature 3 proposes an approach using scalar quantization to reduce a memory amount needed in specific object recognition. In this approach, values that each dimension of a feature vector representing each local feature can take are limited to discrete values, whereby reduction of the memory amount is realized. That is, the value of each dimension is limited to a value having a predetermined bit length. Although the number of local features registered in an image database does not vary, a memory amount needed for storing each local feature is decreased. Therefore, the whole memory amount needed for the image database is reduced.
<Extraction of Feature Vectors>
In the present embodiment, local features (feature vectors) are extracted from a reference image and a query image by using PCA-SIFT.
Non-Patent Literature 3 states that even if each dimension of a feature vector obtained by using PCA-SIFT is represented by 2 bits, the recognition rate in image recognition hardly varies. The value of each dimension of a feature vector extracted by using PCA-SIFT is, if the value is represented as a short-type integer, represented by 16 bits. Therefore, if each dimension of a feature vector is reduced to 2 bits through scalar quantization, a memory amount needed for one feature vector becomes about ⅛ of the original memory amount. Although a memory amount for an image database also includes memory amounts needed besides the memory amount for storing each feature vector, Non-Patent Literature 3 states that, even in consideration of such memory amounts, it is possible to reduce the memory amount for the image database to about ⅓ of the original memory amount.
<Comparison between Query Feature Vector and Reference Feature Vector>
Image retrieval is performed by a query feature vector and a reference feature vector being compared with each other. In the comparing processing, the distance between each query feature vector extracted from a query image, and each reference feature vector registered in an image database is calculated, and a reference feature vector that is a near neighbor of the query feature vector is determined. Then, an image ID associated with the determined reference feature vector is obtained.
<Determination of Reference Image as Recognition Result>
Processing of determining a result of image recognition, based on the result of the comparison, is performed. In this processing, votes are given to the image IDs obtained in the comparing processing, to which the query feature vectors correspond, and then a reference image indicated by an image ID that has obtained the most votes is determined as a recognition result.
The accuracy of the distance calculation is deteriorated as a result of the scalar quantization. One of reasons why the recognition rate hardly varies in spite of the deterioration is that erroneous image IDs are removed in accordance with rule of majority in the voting.
<<Memory Amount Reduction Method by Sifting Selection of Local Features>>
The inventors focused on sifting selection of feature vectors as a method for reducing a memory amount for an image database by an approach different from the above-described method using scalar quantization.
<Guideline for Sifting Selection>
Also in a method for reducing a memory amount by sifting selection of reference local features, local features are extracted by using PCA-SIFT.
The number of local features extracted from a reference image differs depending on the content of the reference image. In the case of using an image database that is in a no-reduction state, for which sifting selection of local features is not performed, all local features extracted from an image are registered into the image database. Therefore, the number of local features to be registered largely differs among reference images. If a reference image includes a large number of local features, a large number of similar local features are sometimes extracted from a specific part of the reference image. It is not necessary to register all the similar local features into an image database. This is because such similar local features will not greatly contribute to improvement in the recognition rate owing to the similarity. Therefore, the maximum number of local features to be registered into an image database per one image is restricted to R, so that a memory amount needed for storing reference feature vectors will be prevented from increasing. If the number of extracted reference feature vectors does not exceed R, all the extracted local features are registered into an image database. If the number of extracted reference feature vectors exceeds R, local features to be registered are selected based on the following idea.
<Clustering>
In the present invention, feature vectors having long vector lengths, which have a relatively robust resistance to variation in a shooting angle, are preferentially selected and registered into an image database. The probability that the entirety of a retrieval target is included in a reference image that is to be a recognition result, and in the corresponding query image, is not low. However, if feature vectors having long vector lengths are mostly included in partial areas of a reference image or a query image, feature vectors included in the area other than the partial areas become noise, and as a result, it becomes difficult to retrieve a reference image corresponding to a query image. In order to cope with such uneven presence in a retrieval target image, k-means clustering with a maximum clustering number of R is performed for coordinate values indicating the positions of reference feature vectors in a reference image from which the reference feature vectors have been extracted.
<Selection of Representative Vector and Registration into Image Database>
Next, a reference feature vector having the longest vector length is preferentially selected from among reference feature vectors included in each cluster obtained by k-means clustering. The selected feature vector is registered into an image database. That is, only a representative vector which represents each cluster is registered into an image database.
Through the above procedure, reference feature vectors are selected in a substantially uniform manner from a reference image, without unevenly selecting reference feature vectors. Therefore, even if only a part of an object to be retrieved is included in a reference image, the probability that the object will be recognized can be increased.
<Method of Approximate Nearest Neighbor Search used in Comparison>
ANN (Approximate Nearest Neighbor) (for example, see Non-Patent Literature 5) can be used for comparison between a query feature vector and a reference feature vector (or a representative vector). ANN is a method of performing approximate nearest neighbor search at a high speed by using a tree structure. Although the accuracy of vector comparison decreases owing to approximation, the processing time taken for retrieval can be reduced.
FIG. 1 shows the concept of approximate nearest neighbor search according to the ANN. It is noted that only cells that are engaged in explanation are shown for the purpose of simplification. Reference feature vectors are registered in an image database such that the reference feature vectors are divided into several cells and form a tree structure. Here, q represents a query feature vector of a query image, and p 1 to p 6 represent reference feature vectors. In addition, it will be assumed that p 1 has been discovered as a near neighbor vector at present. r is the distance between the query feature vector q and the reference feature vector p 1 . In the case of executing nearest neighbor search, cells overlapped by a hypersphere indicated by a solid line are targets of retrieval because there is a possibility that a reference feature vector that is a nearer neighbor vector than p 1 , that is, a reference feature vector whose distance to q is smaller than r is present in the cells. On the other hand, in the case of executing approximate nearest neighbor search, a hypersphere defined by applying a tolerance error ε to the distance r which is a distance to p 1 is set, and only cells overlapped by the set hypersphere are targets of retrieval.
r/(1+ε) [Expression 1]
In this case, although there is a possibility that a reference feature vector that is the nearest neighbor (p 3 in FIG. 1 ) cannot be discovered, the number of cells to be retrieved decreases, whereby the retrieval time can be reduced.
In the method of the present invention, there is a possibility that a reference feature vector that is the nearest neighbor (reference feature vector that is to be an answer) corresponding to a query feature vector is not present, because of reduction of local features. Therefore, only when the distance d between a query feature vector and a reference feature vector associated with each other as a result of the comparison by ANN is smaller than a predetermined threshold value t, a vote is given to the corresponding image.
<<Experiments>>
<Reference Image and Image Database>
Experiments for verifying the effectiveness of the sift selection of local features were conducted. An image database in which 100,000 reference images were registered was used in the experiments. The image database of 100,000 reference images included three data sets A, B, and C. The data set A included 3,100 images collected by using Google image search. Search keywords used in collection of the images included “Poster”, “magazine”, “cover”, and the like. The data set B included 18,500 images published on a site of PCA-SIFT. The data set C included 78,400 images collected on “flickr” which is a photograph sharing site by using tags of “animal”, “birthday”, “food”, “japan”, and the like. The data set C mainly included photographs of an object, nature, a person, and the like.
FIG. 2 shows examples of the reference images collected through the above procedure.
It is noted that, in collecting reference images, images having sizes equal to or smaller than 600×600 pixels were excluded, and the sizes of reference images were reduced such that the longitudinal sides of the reference images were equal to or smaller than 640 pixels. The sizes of the reference images were almost equal to a VGA size.
Then, local features were extracted from the reference images by using PCA-SIFT (PCA-SIFT provided on http://www.cs.cmu.edu/yke/pcasift/ was used). The total number of the extracted local features was 1.82×10 8 . The total number of local features extracted from a database of 10,000 reference images, which is a sub set of the above image database, was 2.07×10 7 .
Then, for the purpose of comparison, a conventional memory amount reduction method using vector quantization according to Non-Patent Literature 4, and a memory amount reduction method using the sifting selection of local features according to the present invention were each applied to the image databases, whereby a total of four image databases were compiled.
<Memory Reduction Method using Vector Quantization>
Here, a conventional memory amount reduction method using vector quantization will be briefly described.
In vector quantization, feature vectors distributed in a certain area in a feature space are grouped. Therefore, it is necessary to define some method for grouping feature vectors. In the present specification, feature vectors are grouped as follows. First, a feature space is divided by using a standard kd-tree splitting rule which is used for generating a kd-tree. In this method, a dimension indicating the largest variance in a feature space is selected, and the feature space is divided at the median value of coordinates of points distributed on the selected dimension. The maximum number (bucket size) b of feature vectors to be included in each divided feature space is set. The feature space is divided until the number of feature vectors included in each divided feature space is equal to or smaller than b. Then, the center of gravity of the feature vectors distributed in each divided feature space is calculated, and the feature vectors in the divided feature space is replaced by a center-of-gravity vector. The center-of-gravity vectors are registered into a database, and image IDs attached to the feature vectors that have been replaced are attached to the respective center-of-gravity vectors, whereby vector quantization is performed.
The center-of-gravity vectors correspond to codewords in vector quantization, and are often called visual words.
<Experiment Parameters>
The values of a parameter b used for compiling an image database by the method using vector quantization are 1, 2, 3, 5, 10, and 20.
On the other hand, the values of a parameter R used for compiling an image database by the memory amount reduction method using sifting selection of local features are 300, 200, 100, 75, and 50. Table 1 shows the numbers, of local features registered in the image database of 100,000 reference images, that correspond to the respective values of R.
TABLE 1
Number of local features registered in database (sifting selection)
Number of local
No-reduction
R
features
ratio [%]
50
4.99 × 10 6
2.7
75
7.49 × 10 6
4.1
100
9.98 × 10 6
5.5
200
1.98 × 10 7
10.9
300
2.94 × 10 7
16.1
<Query Image>
100 reference images, 200 reference images, and 200 reference images, i.e., 500 images in total, were selected in a random manner from the data sets A, B, and C, respectively, to obtain retrieval targets. Therefore, reference images to be recognized as the retrieval targets were necessarily included in the image database. Next, these retrieval targets were printed on sheets of A4 paper, and the resultant sheets were shot by a camera.
FIG. 3 shows examples of the shot images. As shown in FIG. 3 , each sheet including the retrieval target was placed such that the entirety of the sheet could be shot, and then the sheet was shot to obtain a shot image while an angle θ of the optical axis of the camera with respect to the sheet was set at 90°, 75°, and 60°. In addition, a part of the sheet was shot, the angle θ being 90°. As a result, four shot images were obtained per one retrieval target. In addition, the sizes of the shot images were reduced to a size of 512×341 pixels to obtain query images, and feature vectors were obtained by PCA-SIFT. As a result, 612 query feature vectors were obtained on average per one query image.
<Determination of Threshold Value t>
First, experiments for examining an appropriate value to be set as the threshold value t of distance for the comparison using ANN, were conducted. Specifically, how the recognition rate varies by the value of t being varied was examined, for each of the compiled image databases. Table 2 shows a result of the experiment obtained when R was set at 50, where R is the maximum number of local features extracted per one reference image in each image database. From the result shown in Table 2, it is found that the recognition rate was high roughly when the threshold value t was set at 3873 and 3162. Also when the value of R was varied, in general, the recognition rate was high roughly when the threshold value t was set at 3873 and 3162. In view of the above result, the threshold value t was set at 3873 in the following experiments.
TABLE 2
Recognition rate with value of t being varied (R = 50)
Recognition rate [%]
Processing
t
Average
60°
75°
90°
Part
time [ms]
∞
92.6
94.4
96.8
96.2
83.0
440.7
4472
92.8
94.4
96.8
96.4
83.4
454.4
3873
93.3
94.0
97.2
97.0
84.8
465.5
3162
93.2
93.0
97.6
96.8
85.2
450.8
2236
90.1
79.8
97.4
96.8
86.4
448.9
<Effectiveness of Sifting Selection of Features>
Next, the following four methods of (A), (B), (C), and (D) were compared. In the method (A), k-means clustering is performed and a feature vector having a long vector length is selected from each cluster. In the method (B), k-means clustering is performed in an image space, for each image, and local features are selected in a random manner from each cluster. In the method (C), some feature vectors having the largest vector lengths are selected from each image. In the method (D), local features are selected in a random manner from each image.
In the above four methods, image databases were compiled by using the same value of R, and the recognition rates were compared to each other. The threshold value t of distance was set at 3873. FIG. 4 shows a result obtained when R was set at 50.
In FIG. 4 , the value on the vertical axis indicates the recognition rate. On the horizontal axis, “average” at the left end indicates an average recognition rate of all recognition rates obtained in the following four conditions. “60°” indicates an average recognition rate for query images shot at a shooting angle of 60°, “75°” indicates an average recognition rate shot at a shooting angle of 75°, “90°” indicates an average recognition shot at a shooting angle of 90°, and “part” indicates an average recognition rate for query images obtained by shooting a part of a sheet. As shown in FIG. 4 , in the case where the entirety of a sheet was shot, the method (A) had the highest recognition rate.
In comparison between the methods (A) and (C) in FIG. 4 , in the case where an image including the entirety of a specific planar object is to be recognized, it can be said that it is advantageous to use feature vectors having long vector lengths, which have robust resistance to variation in the shooting angle.
However, in the case where feature vectors having long vector lengths were merely registered as in the method (C), if a query image including only a part of a retrieval target was used, the recognition rate significantly decreased. One of possible reasons for the decrease is that feature vectors having long vector lengths were mostly present outside a shooting range of a query image, and as a result, a query feature vector and a reference vector could not successfully be compared.
On the other hand, in the case where k-means clustering is used and local features are evenly selected from every portion of an image as in the method (A), the recognition rate was largely restored. Therefore, it can be said that it is important to evenly select feature vectors having long vector lengths from an image.
Table 3 shows the recognition rate obtained in the method (A) while the value of R is varied. ∞ indicates the case where the maximum number of local features to be registered into an image database was not restricted.
TABLE 3
Recognition rate with value of R being varied (t = 3873)
No-reduction
Recognition rate [%]
Processing
ratio [%]
Average
60°
75°
90°
Part
time [ms]
100
98.7
97.8
99.0
99.0
99.0
1038
16.1
98.8
98.4
99.0
99.0
98.8
778.6
10.9
98.4
98.2
98.6
98.6
98.0
658.8
5.5
97.6
97.6
98.2
98.6
95.8
553.5
4.1
96.7
96.8
98.2
97.8
94.0
537.2
2.7
93.3
94.0
97.2
97.0
84.8
465.5
As shown in Table 3, even in the case where a memory amount for an image database was reduced to about 10% of the original memory amount, a recognition rate of 98% or more was realized. As the value of R decreased, a query image including a part of a sheet began to decrease, and the degree of the decrease gradually became large. It is considered that this is because feature vectors having long vector lengths were selected.
As shown in the above experiments, if sifting selection of local features was performed in consideration of the vector lengths of feature vectors and the uniformity of distribution of feature vectors in an image space, even in the case of using an image database having a size of about 1/10 of an image database that is in a no-reduction state, a recognition rate of 98% was obtained, whereby the effectiveness of the memory amount reduction method of the present invention was verified.
Various modifications of the present invention may be attained other than the above mentioned embodiment. Such modifications should not be deemed to be out of the scope of the present invention. The present invention should include all the modifications within the scope of the claims, their equivalents, and within the above scope.
Industrial Applicability
The present invention is highly effective for, when specific object recognition is to be performed for a large-scale image database including several tens of thousands of images or several hundreds of thousands of images by using local features obtained by SIFT (Scale-Invariant Feature Transform) or the like, compiling the image database.
In the case of using a large-scale image database for specific object recognition, the number of local features (feature vectors) to be stored in the image database is large. Therefore, a problem that a memory amount needs to be reduced arises. According to the present invention, by using modified method for sifting selection of local features, it becomes possible to save a memory amount needed for storing local features in an image database.
Description of the Reference Characters
p 1 , p 2 , p 3 , p 4 , p 5 , p 6 feature vector in image included in image database
q feature vector of query
r distance between vectors p 1 and q, i.e., radius
|
A method for creating an image database comprising an extraction step of extracting reference feature vectors from a reference image which should be compared with a retrieval query image for object recognition, the reference feature vectors corresponding to local features at different positions of the reference image and representing the position and characteristics of each of the local features as a vector position, vector length, and a vector direction, a clustering step of creating a plurality of clusters consisting of different reference feature vectors in such a manner that each reference vector belongs to any of the plurality of clusters, a selection step of selecting the representative vector of the clusters from among the reference feature vectors of each of the clusters, and a step of associating the representative vector with the reference image and registering the representative vector associated therewith in the image database for the object recognition, wherein, in the clustering step, each of the clusters is created in such a manner that reference feature vectors at a near vector position belong to the same cluster, and in the selection step, reference feature vectors with long vector length are given priority to select the representative vector, and wherein the retrieval query image and the reference image are compared with each other by generating at least one query feature vector from the retrieval query image, and applying local search between the query feature vector and the representative vector, each of the steps being executed by computers.
| 6
|
BACKGROUND
Field
[0001] Microelectromechanical systems (MEMS) include micro mechanical elements, actuators, and electronics. Micromechanical elements may be created using deposition, etching, and/or other micromachining processes that etch away parts of substrates and/or deposited material layers or that add layers to form electrical and electromechanical devices. One type of MEMS device is called an interferometric modulator. As used herein, the term interferometric modulator or interferometric light modulator refers to a device that selectively absorbs, transmits, and/or reflects light using the principles of optical interference. In certain embodiments, an interferometric modulator may comprise a pair of conductive plates, one or both of which may be transparent and/or reflective in whole or part and capable of relative motion upon application of an appropriate electrical signal. In a particular embodiment, one plate may comprise a stationary layer deposited on a substrate and the other plate may comprise a metallic membrane separated from the stationary layer by an air gap. As described herein in more detail, the position of one plate in relation to another can change the optical interference of light incident on the interferometric modulator. Such devices have a wide range of applications, and it would be beneficial in the art to utilize and/or modify the characteristics of these types of devices so that their features can be exploited in improving existing products and creating new products that have not yet been developed.
SUMMARY OF THE INVENTION
[0002] One aspect of the invention is a dimming mirror, comprising a plurality of interferometric light modulators and a control circuit adapted to configure the plurality of interferometric light modulators to at least one of a plurality of predefined states, including a first state having a substantially reflective appearance and a second state having a dimmed visual appearance as contrasted with the first state.
[0003] Another aspect of the invention is a method of using a dimming mirror, comprising receiving a signal indicative of one of a plurality of predefined states, including a first state having a substantially reflective appearance and a second state having a dimmed visual appearance as contrasted with the first state and setting a plurality of interferometric light modulators into the indicated state.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is an isometric view depicting a portion of one embodiment of an interferometric modulator display in which a movable reflective layer of a first interferometric modulator is in a relaxed position and a movable reflective layer of a second interferometric modulator is in an actuated position.
[0005] FIG. 2 is a system block diagram of a dimming mirror comprising an array of interferometric modulators.
[0006] FIGS. 3A-3D illustrate exemplary embodiments of the invention using different input devices.
[0007] FIGS. 4A-4J illustrate examples of the plurality of states the array of interferometric modulators can be configured to take.
[0008] FIG. 5 is a system block diagram of another embodiment of the invention.
[0009] FIGS. 6A-6C show another use for the array of interferometric modulators within the dimming mirror to display information.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0010] Typical usage of an interferometric light modulator involves taking advantage of the optical properties of the device. In some embodiments, the interferometric light modulator is a bistable device having two states, each with different optical properties. The state a particular modulator is in is controllable by the application of an appropriate electrical signal. Thus, the interferometric light modulator is well-suited for display applications. Interferometric modulators can be used in a variety of display applications, including motion (e.g., video) or stationary images (e.g., still image), and whether textual or pictorial. Interferometric modulators may be used in or associated with a variety of electronic devices such as, but not limited to, mobile telephones, wireless devices, personal data assistants (PDAs), hand-held or portable computers, GPS receivers/navigators, cameras, MP3 players, camcorders, game consoles, wrist watches, clocks, calculators, television monitors, flat panel displays, computer monitors, auto displays (e.g., odometer display, etc.), cockpit controls and/or displays, display of camera views (e.g., display of a rear view camera in a vehicle), electronic photographs, electronic billboards or signs, projectors, architectural structures, packaging, and aesthetic structures (e.g., display of images on a piece of jewelry).
[0011] More simply, taking advantage of the bistable nature of a modulator, an array of interferometric modulators can take on a plurality of states, wherein each state represents a transition from fully reflective to a dimmed state. Such an array could find use, among other applications, as the rear-view mirror of a vehicle. Such a designed mirror could be dimmed to reduce glare from the headlights of other vehicles. The user of a dimming mirror comprising an array of interferometric modulators may set the array in one of a plurality of preconfigured states, wherein each state represents a transition from a reflective state to a dimmed state. It is also possible to equip the dimming mirror with a sensor, which would sense the amount of light impinging on the mirror and adjust the array of interferometric modulators accordingly.
[0012] FIG. 1 is an isometric view depicting a portion of one embodiment of an interferometric modulator array in which a movable reflective layer of a first interferometric modulator is in a relaxed position and a movable reflective layer of a second interferometric modulator is in an actuated position. The depicted portion of the modulator array in FIG. 1 includes two adjacent interferometric modulators 12 a and 12 b . In the interferometric modulator 12 a on the left, a movable reflective layer 14 a is illustrated in a relaxed position at a predetermined distance from an optical stack 16 a , which includes a partially reflective layer. In the interferometric modulator 12 b on the right, the movable reflective layer 14 b is illustrated in an actuated position adjacent to the optical stack 16 b.
[0013] The optical stacks 16 a and 16 b (collectively referred to as optical stack 16 ), as referenced herein, typically comprise several fused layers, which can include an electrode layer, such as indium tin oxide (ITO), a partially reflective layer, such as chromium, and a transparent dielectric. The optical stack 16 is thus electrically conductive, partially transparent, and partially reflective, and may be fabricated, for example, by depositing one or more of the above layers onto a transparent substrate 20 . The partially reflective layer can be formed from a variety of materials that are partially reflective such as various metals, semiconductors, and dielectrics. The partially reflective layer can be formed of one or more layers of materials, and each of the layers can be formed of a single material or a combination of materials.
[0014] In some embodiments, the layers of the optical stack 16 are patterned into parallel strips, and may form row electrodes in a display device as described further below. The movable reflective layers 14 a , 14 b may be formed as a series of parallel strips of a deposited metal layer or layers (orthogonal to the row electrodes of 16 a , 16 b ) deposited on top of posts 18 and an intervening sacrificial material deposited between the posts 18 . When the sacrificial material is etched away, the movable reflective layers 14 a , 14 b are separated from the optical stacks 16 a , 16 b by a defined gap 19 . A highly conductive and reflective material such as aluminum may be used for the reflective layers 14 , and these strips may form column electrodes in a display device.
[0015] With no applied voltage, the gap 19 remains between the movable reflective layer 14 a and optical stack 16 a , with the movable reflective layer 14 a in a mechanically relaxed state, as illustrated by the pixel 12 a in FIG. 1 . However, when a potential difference is applied to a selected row and column, the capacitor formed at the intersection of the row and column electrodes at the corresponding pixel becomes charged, and electrostatic forces pull the electrodes together. If the voltage is high enough, the movable reflective layer 14 is deformed and is forced against the optical stack 16 . A dielectric layer (not illustrated in this Figure) within the optical stack 16 may prevent shorting and control the separation distance between layers 14 and 16 , as illustrated by interferometric light modulator 12 b on the right in FIG. 1 . The behavior is the same regardless of the polarity of the applied potential difference. In this way, row/column actuation that can control the reflective vs. non-reflective pixel states is analogous in many ways to that used in conventional LCD and other display technologies.
[0016] FIG. 2 is a system block diagram of a dimming mirror comprising an array of interferometric modulators. In one embodiment of the invention, the dimming mirror comprises an array of interferometric modulators 22 , an input device 24 , a sensor 26 , and a control circuit 28 . In other embodiments, the dimming mirror comprises only one of an input device 24 and a sensor 26 . It may be advantageous, in an embodiment with both an input device 24 and a sensor 26 to have a switch (either logical or physical) between the input device 24 and the sensor 26 to avoid conflicting signals being received at the control circuit. In an exemplary operation, the control circuit receives signals from either the input device 24 or sensor 26 causing the array of interferometric modulators to be in one of a plurality of preconfigured states. In some embodiments, the control circuit 28 will be responsible for determining which of the plurality of preconfigured states to cause the array of interferometric modulators 26 to be in based on a signal received from the sensor 26 . The sensor may be configured, for example, to measure the brightness of light on the sensor.
[0017] FIGS. 3A-3D illustrate exemplary embodiments of the invention using different input devices. In FIG. 3A , the input device is a slider 32 . In some embodiments, the plurality of preconfigured states is ordered by a dimming value. By sliding the slider 32 to, e.g., the right, the array 22 would be placed in a preconfigured state with a smaller dimming value. By sliding the slider 32 in the opposite direction, the array of interferometric modulators 22 would take one of the preconfigured states with a greater dimming value. In FIG. 3B , the input device is a set of two buttons 34 a , 34 b . By pressing the brighten button 34 b , the array 22 would take a preconfigured state with a lower dimming value. Similarly, by pressing the dim button 34 a , the array 22 would take a preconfigured state with a higher dimming value. The dimming mirror of FIG. 3B may also be embodied with one button, which causes the array of interferometric modulators 22 to take either a darker or lighter state, and when the array 22 has reached its darkest or lightest state, another press of the button cycles back to the lightest or darkest state, respectively. The dimming mirror may also be equipped with a plurality of buttons, each button corresponding to one of the preconfigured states. In FIG. 3C , the input device is a dial 36 having much the same functionality as the slider. In FIG. 3D , the input device is replaced by a sensor 38 . In this case, the sensor would detect the brightness of light on the sensor, and thus, the mirror, and adjust the dimming value of the array accordingly.
[0018] FIGS. 4A-4J illustrate examples of the plurality of states the array of interferometric modulators can be configured to take. In FIGS. 4A-4J , the white squares represent interference modulators in a reflective state, and the darkened squares represent interference modulators in a dimmed state. The array of interference modulators can be designed such that each modulator is reflective in the released state and dimmed in the actuated state. The array of interference modulators can also be designed where the opposite is true, such that each modulator is dimmed in the released state and reflective in the actuated state. Although FIGS. 4A-4J illustrate examples of the plurality of states the array of interferometric modulators can be configured to take, the invention does not require that each of these states are available, or preclude the use of other states. Also, FIGS. 4A-4J illustrate the use of a rectangular array of interference modulators, but this does not have to be the case. The array may be designed such that individual rows are offset from neighboring rows, or there may be a different number of modulators in each row. FIG. 4A illustrates a state in which all of the interferometric modulators are in a reflective state. FIG. 4B illustrates a state in which only 89% of the interferometric modulators are in a reflective state. Although this state shows the case where most of the dimmed modulators share a similar row or column with other dimmed modulators, this is not a necessary feature of this state, or of the invention. Each row may be advantageously offset to avoid negative optical effects, such as those associated with regular arrays. FIG. 4C illustrates a state in which only 75% of the interferometric modulators are in a reflective state. FIG. 4D illustrates a state in which only 55% of the interferometric modulators are in a reflective state. FIG. 4E illustrates a state in which only 50% of the interferometric modulators are in a reflective state. FIG. 4F illustrates a state in which only 45% of the interferometric modulators are in a reflective state. FIG. 4G illustrates a state in which only 25% of the interferometric modulators are in a reflective state. FIG. 4H illustrates a state in which only 11% of the interferometric modulators are in a reflective state. FIG. 4I illustrates a state in which none of the interferometric modulators are in a reflective state. FIGS. 4A-4I illustrate only a few of the multitude of options for the plurality of states which the array of interferometric modulators can take, and are meant in no way to be limiting. Although FIG. 4A-4I have shown regular patterns, irregular, or even random, patterns can be used as a state of the array of interferometric modulators as shown in FIG. 4J . Through the use of irregular, or even random, patterns such as the one shown in FIG. 4J it is possible that the plurality of states are not predetermined, but created randomly by the control circuit in response to a request to increase or decrease the dimming value of the state of the array of interference modulators.
[0019] As the above described dimming mirror includes an array of interferometric light modulators, it may be possible to use the same array for other purposes, such as displaying images or information. FIG. 5 is a system block diagram of another embodiment of the invention. In this embodiment, the dimming mirror comprises an array of interferometric modulators 22 , an input device 24 , a sensor 26 , a control circuit 28 , a processor 52 , a memory 54 , an image source module 56 , and a transceiver 58 . The transceiver 58 can additionally serve as a transmitter or receiver. A variety of other uses of the array of interferometric modulators 22 can be achieved using this embodiment of the invention. For example, the array may be quickly alternated between the fully reflective and fully dimmed state as an indicator of an event, such as the need to check the engine, being low on fuel, or an incoming phone call. As another example, the right half of the dimming mirror may be quickly alternated between fully reflective and fully dimmed to indicate that the driver of a vehicle will need to soon turn right. FIGS. 6A-6C shows another use for the array of interferometric modulators within the dimming mirror. In this example, the array displays an arrow progressively moving to the right, to indicate, for example that the driver of a vehicle will need to soon turn right, or that the right turn indicator is active. The image source module 56 may receive new image information via the transceiver 58 for application on the array of interferometric modulators 22 .
[0020] The foregoing description sets forth various preferred embodiments and other exemplary but non-limiting embodiments of the inventions disclosed herein. The description gives some details regarding combinations and modes of the disclosed inventions. Other variations, combinations, modifications, modes, and/or applications of the disclosed features and aspects of the embodiments are also within the scope of this disclosure, including those that become apparent to those of skill in the art upon reading this specification. Thus, the scope of the inventions claimed herein should be determined only by a fair reading of the claims that follow.
|
A dimming mirror comprises an array of interferometric light modulators is disclosed. In one embodiment of the invention, the dimming mirror comprises a plurality of interferometric light modulators and a control circuit adapted to configure the plurality of interferometric light modulators to at least one of a plurality of predefined states, including a first state having a substantially reflective appearance and a second state having a dimmed visual appearance as contrasted with the first state. Additional features may include additional states having an appearance with a dimmed visual appearance as contrasted with the first state and a reflective appearance as contrasted with the second state.
| 6
|
BACKGROUND OF THE INVENTION
This invention relates to improvements in apparatus for adjustably supporting a workpiece or the like while an operation is performed on the workpiece. The invention herein disclosed may be embodied as a part of or as an attachment to any of several different varieties of grinding machines.
It is of course well known in the art to provide a supporting member upon which a workpiece to be ground can be supported with respect to a grinding device, but in most instances, the arrangement is sufficiently inexact as to make it very difficult for a number of similarly configured workpieces to be ground in a consistently repeatable manner.
It was in an effort to overcome the shortcomings of such prior art devices as these that the present invention was evolved.
SUMMARY OF THE INVENTION
A highly satisfactory means for supporting a workpiece or component to be ground to size by the use of a grinding device may, in accordance with this invention, comprise a base member having a work-supporting means operably associated therewith, with the base member and the work-supporting means being operably interconnected, preferably by the use of a hinge member. The hinge member or hinge means makes it possible for the relationship of the work-supporting means to the base member to be readily changed by a user, should such be desired.
The work-supporting means has thereon a work-clamping device, with this work-clamping device being constructed and arranged to hold a workpiece or component to be ground in a selected position. The workpiece is supported in such a manner that a portion of the workpiece can be brought into direct contact with a grinding means, such as a bench grinder, belt grinder, disk grinder or the like.
Advantageously, a depth-controlling member is operably mounted upon the base member, with part of such member being in contact with the workpiece to be ground. The relationship of the depth-controlling member with respect to the base member can be readily adjusted. By a part of the depth-controlling member being in contact with the workpiece, the user, by controlling the position of the depth-controlling member, is selectively able to determine the amount of material removed from the workpiece by the grinding device. This highly significant arrangement makes it readily possible for a user to grind a large number of workpieces in a consistent and repeatable manner.
After a workpiece or component has been ground to a selected size and configuration it can, most significantly, be released without altering the position of the depth-controlling member by relative movement of the work-supporting means with respect to the base member, accomplished by the utilization of the hinge means.
Latch means are preferably utilized for controlling the relationship of the work-supporting means to the base member, with this latch means normally holding the work-supporting means in a rigid relationship to the base member. Upon manipulation of the latch means by a user, the work-supporting means can be readily moved about the hinge with respect to the base member.
Position-controlling means are attached to the work-supporting means, with this position-controlling means being usable for establishing a precise position of the work-clamping device and therefore the workpiece with respect to the grinding device. Means are provided for enabling a user to adjust the relationship of the position-controlling means to the work-supporting means.
One embodiment of our invention is particularly adopted to be used in conjunction with a single axis component, such as a bolt, rod or the like, whose end is to be ground in a particular manner. Another embodiment is adapted for the mounting thereon of a multiaxis component such as a U-bolt or the like. If desired, the user can accurately, and repeatably, grind the legs of the U-shaped member to a desired angularity, and the legs to different lengths.
It is to be understood that our novel device is readily adapted to be supported in operative relation to a bench grinder, belt grinder, disk grinder or the like, for generating and duplicating both simple and complex contours.
It is a primary object of this invention to provide a device of straightforward and inexpensive construction, making it readily possible to consistently grind a number of differently shaped workpieces to a desired length and angularity.
It is another object of this invention to provide a means for mounting a workpiece of specified construction, such as of U-shaped configuration, in a workpiece-receiving device held in operative relationship to a grinder means, with the workpiece being mounted in such a way as to enable a user to grind numerous workpieces to a consistent angularity and length.
It is yet another object of this invention to provide a base member interconnected with a novel workpiece-supporting device by the use of hinge means, with this arrangement making it readily possible to remove an already-ground workpiece from the workpiece-supporting device, and then insert a new workpiece to be ground to a specified configuration, without having to modify the desired relationship of the workpiece to a depth-controlling member utilized in cooperation with the base member, which member is utilized for assuring a consistent relationship of the workpiece to the grinder means.
It is yet still another object of our invention to provide a base member supporting a pair of positioning rods disposed in a spaced-apart, parallel relationship to the base member, where a work-supporting means operatively associated with such base member supports a workpiece to be ground at a specific angle, with the appropriate placement of the positioning rods in dissimilar positions enabling the end or ends of a single workpiece, or of a plurality of similar workpieces, to be ground to a specific and consistent angle. If desired, a protractor may be mounted on the base member, for simplifying the accurate positioning of the positioning rods.
These and other objects, features and advantages will become more apparent from a study of the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of our novel hand-held tool arranged to support a single axis component such as a bolt in a position enabling a selected, precise amount of metal to be removed from one end of the bolt as a result of contact with a grinding means;
FIG. 1a fragmentary perspective view to a large scale of the clamping arrangement utilized in FIG. 1 for holding a single axis component a rotatable relationship, with a portion of the clamping device broken away to reveal internal construction;
FIG. 1b is a fragmentary perspective view of the arrangement that may be utilized for securing the work-clamping arrangement in a desired location with respect to the work-supporting means, with a portion of the device broken away to reveal details of the mounting arrangement;
FIG. 2 is perspective view illustrating how the work-supporting means of our novel hand-held tool can be rotated downwardly about a pivot location so as to permit the removal of an already-ground component and the substitution of a new component, this being accomplished without affecting the accuracy of the depth-establishing device we utilize on the base member in order to obtain consistency of length and angularity of the components being ground;
FIG. 2a is a fragmentary view to a somewhat larger scale revealing the use of adjustable spacing device in conjunction with the grinding of the single axis component of the type revealed in FIG. 1;
FIG. 3 is a perspective view similar to FIG. 1, but in this instance utilizing a somewhat enlarged work-supporting means, the construction of which enables U-shaped components of various sizes to be held to a precise angularity, such that the ends of each of a series of U-shaped components can be ground in a consistent manner;
FIG. 4 is a plan view of our device, revealing in full lines that our novel hand-held device utilizes separately adjustable positioning rods, enabling each of a series of U-shaped components to be ground to a consistent angularity and length, and also revealing by the use of dashed lines how each of a series of U-shaped components may be ground in such a manner that both legs of a U-shaped compare of identical length;
FIG. 5 s a view similar to FIG. 3 but showing the use of an even larger work-supporting means than depicted in FIG. 3, in order that U-shaped components of substantial width can be ground in a desirable manner; and
FIG. 5a is a fragmentary view of the arrangement utilized to hold the protractor of FIGS. 4 and 5 in a selected rotational position.
DETAILED DESCRIPTION
With initial reference to FIG. 1, it will there be seen that we have illustrated a portion of a tool 10 configured to hold a component or workpiece such as a bolt B, in such a position as to readily permit the outer end of the component to be ground to a certain length and/or a certain angle, by contact with a grinding means such as bench grinders, belt grinders, disk grinders and the like. However, our tool is not limited to use with grinding devices, for it could be used with other type devices on certain occasions
Our tool 10 is principally made up of a base member 12, having a handle portion 14, and a work-supporting means 20, which is equipped with a work-clamping device 30 serving to support in a very appropriate and stable manner, a bolt B or other such component or workpiece to be ground or contoured in accordance with a carefully designed mounting arrangement described in detail hereinafter. On the opposite end of the base member 12 from the handle portion 14 is a clevis-shaped (fork-shaped) arrangement 16, between the members of which an elongate portion 22 extends. The elongate portion 22 is a part of the work-supporting means or member 20, with a latch member 23 disposed on the end of the portion 22 farthest from the work-clamping device 30 utilized for supporting the component B.
It is to be understood that a longitudinal centerline 28--28 passes through the base member 12 and the work-supporting means 20, with both of these members being symmetrically disposed about the longitudinal centerline 28--28.
An interconnection means is utilized for operably connecting the base member to the work-supporting means, which interconnection means preferably takes the form of a hinge pin 26. The hinge pin is disposed in a perpendicular relationship to the centerline 28--28, with the hinge pin passing through suitable aligned apertures in the portions 16 and 22. Pin 26 is thus being utilized to hold the base member and the work-supporting means in what may be regarded as a hinged relationship. We may also regard the pin 26 as being an intrinsic part of a hinge, hinge means or hinge member. The normal or operative relationship of the base member 12 and the work-supporting means 20 is illustrated in FIG. 1, where the latch member 23, by its interaction with spring biased latch pin 24, serves to hold the members 12 and 20 in a fixed relationship. Preferably the base member 12 and the work-supporting means reside in what may be regarded as a common plane. We refer collectively to the latch member 23 and the latch pin 24 as the latch means.
With reference now to FIG. 2, it will be noted that in this figure we reveal the work-supporting means 20 having been moved downwardly for at least 90° about the hinge pin 26, and preferably for an angular extent of 135°. By the work-supporting means 20 being rotated for a limited yet substantial extent about the hinge pin 26, the work-clamping device 30 assumes a position such that an already-ground component B can be readily removed from the work-clamping device 30, and a new component to be ground easily substituted. Quite significantly, this is readily accomplished without disturbing the depth settings we utilize for consistency in the grinding of workpieces, which features we will describe hereinafter.
As will be noted from FIG. 2, the latch member 23 is located on the far side of the hinge pin 26 from the work-clamping device 30, and from FIG. 1 it will be noted that the work-clamping device 30 as well as the component B carried therein are located upon the longitudinal centerline 28--28, and mounted quite close to the front end of the work-supporting means 20.
It is thus to be seen that the hinge arrangement involving the pin 26 makes it readily possible for the work-supporting means 20 to be selectively moved from the operational position or co-planar relationship with the base member 12 as shown in FIG. 1, to an angular relationship with the base member 12 as depicted in FIG. 2. Then, after a new component to be ground has been inserted into the work-clamping device 30 subsequent to the removal of the already-ground component, the work-supporting means is returned to the operational position depicted in FIG. 1, FIG. 3, and certain other figures. The previously mentioned spring biased latch pin 24, hereinafter described at further length, is positioned to engage the rigidly mounted latch member 23, and thus hold the work-supporting means 20 stably in the operational position, in which it is coplanar relationship with base member 12.
In the embodiment of our invention depicted in FIGS. 1 and 2, the work-supporting means 20 is comparatively narrow, which is ideal when a single axis component such as a bolt, rod or the like is being ground by the use of a grinding device.
It is important to note that we are not to be limited to the specific type of work-supporting means 20 depicted in FIGS. 1 and 2, for as will be seen in detail hereinafter, we may substitute a work-supporting means of a different configuration for the work-supporting means 20 when a different type of component or workpiece is to be ground. FIGS. 3 through 5 depict work-supporting means of somewhat larger size, which may support components of U-shaped configuration, for example.
To facilitate the substitution of one work-supporting means for another, we prefer to utilize a hinge pin 26 having a raised shoulder at one end. A knurled nut or other securing means is utilized at the other end of the hinge pin to prevent unwanted displacement of the pin from its position connecting the base member 12 to the selected work-supporting means.
With reference now to FIG. 1a, it is to be seen that a portion of the work-clamping device 30 has been cut away so as to reveal that a structural member 32 is utilized upon the work-supporting means 20 for supporting a housing 34 of generally circular configuration. The underside of the housing 34 is typically welded to the upper surface of the structural member 32. The housing 34 has a circular interior in which a needle bearing 36 is operatively mounted. The interior of the needle bearing 36 receives a circular bushing 38, in the interior of which bushing, the workpiece or component B to be ground can be closely received. We prefer for the bushing to be press-fitted into the needle bearing 36, so that these members in effect become one unit, hereinafter referred to as a bushing unit. We prefer to use a locking device 39 known as a grub screw for maintaining the selected bushing unit in the desired location in the housing 34.
Knowing the diameter of a specific component B to be ground, we select a bushing 38 whose inner diameter will rather closely receive the component B. We prefer to stock a series of bushing units of graduated sizes, so that a comparatively wide range of components to be ground can be readily accepted. Because of the provision of the needle bearings, the single axis component B carried in the bushing can rotate during the procedure of grinding the end of the component.
Inasmuch as we may wish to mount components of different size and configuration on the end of the work-supporting means 20, we arrange for the position of the work-clamping device 30 on the work-supporting means to be readily adjustable, and to that end we utilize suitable position-controlling means 40, one aspect or part of which is a slot 42 extending for some distance along the work-supporting means 20. The slot 42, best seen in FIGS. 1 and 1b, is disposed along the longitudinal centerline 28--28, and extending through this slot are a pair of bolts 44. The bolts 44, visible in FIG. 1b, engage threaded holes 46 provided in the underside of the structural member 32, so that when the member 32 has been slid to an appropriate position on the work-supporting means 20, the bolts 44 may be tightened so as to hold the structural member 32 tightly in the desired position in the slot 42. The heads of the bolts 44 are of large enough size as to engage the work-supporting means 20 on both sides of the slot 42.
When our device is to be utilized with a component to be ground that is of a length or configuration substantially different from that previously ground, it is desirable to loosen the bolts 44 so that the structural member 32 can if necessary be moved to a new location on the work-supporting means 20. We may refer to the bolts 44 as the adjustment means enabling a user to readily adjust the position or relationship of the work-clamping device to the work-supporting means. It is to be borne in mind that the bushing unit, comprising a needle bearing 36 and bushing 38, can be removed so that a bushing unit having the correct inside diameter can be substituted in order to properly receive the new component. Typically the bushing does not impose more than a relatively small restraint upon the longitudinal positioning of the workpiece therein.
It is important to note that means must be provided for preventing the component B from "retreating" when the outer end of such component is brought into forceful contact with the grinding means. To that end, we provide in accordance with this invention, a novel, highly advantageous depth-establishing device 50 that can be adjusted to come into contact with the end of the component B remote from the end being ground, thus to effectively prevent the component from moving along its longitudinal axis away from the grinding means.
Of significance to this invention is the depth-establishing device 50 we prefer to use, which is to be seen in FIG. 1 to involve the use of a mounting means 52 secured on the base member 12 at a location remote from the handle portion 14, or in other words, the mounting means 52 is located comparatively near the location of the hinge pin 26. On the mounting means 52 a collet member 54 is operably mounted, with the interior diameter of the collet member being such as to slidably receive a slide member or slidably mounted depth-controlling member 56. The front end of the slide rod or depth-controlling member 56 of the depth establishing device 50 has an enlarged, component-contacting member 58, so that components to be ground can be of a widely varying size and/or configuration, with the enlarged member 58 assuredly being of sufficient size to contact the end of the component B remote from the end to be ground or contoured. For obvious reasons we may refer to the slide member or depth-controlling member 56 as being a depth-controlling member or depth-controlling means, whose longitudinal position may be readily adjusted by the user. To be noted is the fact that we may provide evenly spaced marks or indicia 57 along the length of slide member or depth-controlling member 56 for facilitating its placement in a particular and consistent longitudinal position or location.
As visible in FIG. 1, our depth-establishing device 50 also includes a tightening device 62 that is operably mounted on the collet 54. As visible in FIG. 3, the tightening device involves a screw-threaded member 64 that is threadedly received in the sidewall of the collet 54, such that the innermost end of the threaded member can be brought into firm contact with the depth-controlling member or slide member 56, in order that the slide member 56 can be locked in a desired position. As is obvious, the slide member or depth-controlling member 56 may be readily adjusted to different positions, and by virtue of this arrangement, the near end of the component or workpiece to be ground can be held firmly in a desired position. Quite importantly, the opposite end of the component or workpiece, which of course is the end to be ground, can be maintained in a desired relationship to the bench or other support member upon which a bench grinder, belt grinder, disk grinder or the like is mounted.
It is thus to be seen that firm contact of the enlarged member 58 of the slide member 56 with the rear (near) end of the component B makes it readily possible for a user of our device to accurately grind the ends of numerous, substantially identical components to a consistent configuration, as will be further described in subsequent figures.
It is to be noted that we provide a pair of vertically disposed slots 68 in the enlarged, component-contacting member 58 in order to provide a ready means for securing a short, horizontally disposed member 70 upon the side of the member 58 opposite the slide member or depth-controlling member 56. A pair of screws (not illustrated) inserted from the backside of member 58 through the slots 68 enable the member 70 to be held in a selected location on the member 58. By loosening such screws, the height of the member 70 can be vertically adjusted to accommodate different shaped and differently sized heads of bolts. This member 70 can also be adjusted to accommodate different thicknesses of U-bolts. A centering pin 74 in the form of a raised cone or tip visible in FIG. 1 is provided in a center location on the horizontally disposed member 70 in order to enable a single axis component such as the component B to spin freely about the centering pin 74. This may be analogized to the use of a centering pin on a lathe.
With regard now to a further consideration of FIG. 1, it will be seen that a cross member 76 is mounted on the lower side of the base member 12, with a pair of essentially parallel mounting rods 78 tightly affixed to the underside of member 76, in what may be regarded as an orthogonal relationship to the longitudinal centerline 28--28 of the members 12 and 20. Supported on each end of the rods 78 is a slide guide or collet, with collet 82 intended to receive the slide member or positioning rod 84, and collet 86 being intended to receive slide member or positioning rod 88. Although the collet 82 and slide member or positioning rod 84 are not shown in FIG. 1, these members are clearly visible in FIG. 4.
It is to be understood that the slide members or positioning rods 84 and 88 are disposed in a spaced-apart, parallel relationship with the longitudinal centerline 28--28 common to the base member 12 and the work-supporting means 20 that together constitute our tool 10. The forwardmost ends of the positioning rods 84 and 88 are intended to be brought into contact with the bench or other structure upon which the grinding means is mounted, to set the relationship of the work-supporting means to the grinding means. We therefore regard the rods 84 and 88 as positioning rods, and as noted in FIG. 4, the forward ends of these rods may be extended to dissimilar positions, which is made clear in the full line position of our novel tool in this figure. It should now be clear that by setting the slide members or rods 84 and 88 in an unequal length relationship, such as illustrated in full lines in FIG. 4, the end or ends of the selected component can be ground to a desired angularity. On the other hand, by setting the slide members or rods 84 and 88 in an evenly spaced relationship, in the manner shown in dashed lines in FIG. 4, the workpiece or component held in the work-clamping device 30 may be ground to have square end or ends. This highly advantageous capability of our device that enables the legs of a U-bolt to be accurately ground to unequal lengths will be described in more detail shortly, in conjunction with subsequent figures.
Readily seen in FIGS. 1 and 2 is a tightening device 92 operably mounted on the collet 86, involving a screw-threaded member 94 that is threadedly received in the sidewall of the collet 86, such that the inner end of the threaded member can be brought into firm contact with the positioning rod or slide member 88, in order that this slide member can be locked in a desired position. As to be seen in FIG. 4, a similar locking device 90 is operably mounted in collet 82, so that the positioning rod or slide member 84 may be locked in a position corresponding to, or deliberately different than, the position of the positioning rod 88.
We may provide evenly spaced marks or indicia 96 along the length of positioning rod or slide member 84, and evenly spaced marks or indicia 98 along the length of positioning rod or slide member 88 for facilitating the accurate placement of these members in a desired location or relationship. As an example, each of the positioning rods may be six inches in length, with the marks or indicia placed every one-half inch, but we are obviously not limited either to this length or to this spacing. As should be quite apparent, the positioning rods 84 and 88 are provided in an array of sizes to accommodate the needs of certain users for relatively short or relatively long rods, depending on the size of the bed of the grinder.
As should now be clear, by virtue of the positioning rods 84 and 88 being able to be secured in positions of different effective lengths, our tool 10 may be disposed in a desired relationship to the bench or other mounting means upon which a rotary grinder, belt grinder or the like is mounted. It is this construction that makes it readily possible for a user to grind the ends of numerous, substantially identical components such as U-bolts to a consistent configuration and angularity, as will be described in conjunction with FIGS. 3, 4 and 5.
There are many instances in which it may be desirable to grind the end of a bolt or other single axis component to a precise length, without regard to the particular angularity of the end of the component. This is of course in contrast with the ability of our device to enable the legs of a U-bolt or the like to be ground to specified unequal lengths and to a particular angularity. As previously mentioned, in FIG. 4 we show in dashed lines, the relationship of the positioning rods 84 and 88 making it possible to grind a square end on a single axis component or a dual axis component.
With reference now back to the embodiments of FIGS. 1 and 2, in order to enable a user to grind a single axis component to a precise length, we prefer to utilize an adjustable spacing device 100 on the underside of the work-supporting means 20, which device 100 is only shown to a slight extent in FIGS. 1 and 2. However we reveal in clearer detail in FIG. 2a that the adjustable spacing device 100 involves a mounting member 102 to which a collet 104 is rigidly attached. A pair of tapped holes 106 are located on the flat side of the mounting member 102, opposite the collet 104. Suitable bolts 108 are to be received in the tapped holes 106, with this arrangement enabling the mounting member 102 and its collet 104 to be mounted on the underside of the work-supporting means 20 in the manner shown in FIGS. 1 and 2. This is accomplished by inserting the bolts 108 into the previously-described slot 42 disposed along the centerline of the work-supporting means 20, with the heads 110 of the bolts 108 being large enough to engage the surface of the means 20 on each side of the slot 42, and with the threaded portions of these bolts extending through the slot 42 so as to engage the tapped holes 106 of the member 102.
Received in the collet 104 is a single slide member or rod 112, with the forwardmost end 114 of this member being available to contact the support means for the grinder means, such as the support member for a grind wheel or grind belt. A tightening means 116, involving a threaded device of the previously described type, threadedly engages a tapped hole located in the sidewall of the collet 104. An inner end of the tightening means may be brought into forceful contact with the slide member or rod 112, so as to secure it firmly in what may be regarded as the appropriate length setting for the slide member or rod 112. By setting the slide member or rod 112 such that the outermost tip 114 is in a desirable relationship to the bench or support for the grinder means, the user, by the use of this adjustable spacing device, can be assured that the outermost end of each successive component B will be ground to a desired and consistent length.
Returning now to a consideration of the previously-described depth establishing device 50 depicted in FIGS. 1 and 2, we regard it as being most important for the user to be able to remove an already-ground component from the selected bushing means without the user having to change the setting of the slide member or depth-controlling member 56. It is for this reason we advantageously provided the hinged relationship depicted in FIG. 2, wherein the work-supporting means 20 is enabled to pivot, on occasion, downwardly about the previously-mentioned hinge pin 26.
To permit the work-supporting means 20 to normally be held in the fully operational relationship with the base member 12 as depicted in FIG. 1, we of course provide the previously-mentioned latch member 23 on the elongate portion 22 of the means 20, which latch member is normally engaged by the spring biased latch pin 24. As previously-mentioned, the latch pin 24 is slidably mounted in a lower portion of the mounting means 52, in accordance with construction that will be discussed in greater detail in conjunction with FIG. 3. As a result of this arrangement, the spring biased latch pin 24 normally resides in a firm, operational contact with the latch member 23 that is rigidly mounted on the elongate portion 22 of the means 20. This latch means or latch arrangement is the same for all embodiments of our invention, and it serves to hold the base member 12 and the work-supporting means 20 in an operational arrangement until such time as the work-supporting means is to be pivoted about the hinge pin 26 to the position depicted in FIG. 2, so that an already-ground workpiece can be removed.
Turning now to a detailed consideration of FIG. 3, it is to be understood that an important purpose of this invention is to enable a U-shaped component C to be supported such that the ends of its legs will reside at a carefully selected angle to a grinding device, such as that depicted at G in FIG. 4. Except for a different configuration of the work-supporting means in FIG. 3, which is now designated as work-supporting means 120, most of the other components of the device depicted in FIG. 3 are the same as were described in conjunction with the embodiment of FIGS. 1 and 2. Therefore, it will be noted that most of the reference numerals utilized on FIG. 3 are the same as those previously used and previously explained.
By the appropriate use of the previously-mentioned slide members or positioning rods 84 and 88, that can be readily adjusted to different lengths and then tightly maintained in the selected positions, it is apparent that our device makes it relatively easy for a user to cause one leg of the U-shaped component C to be longer than the other leg, and to cause the end of the one leg of the U-shaped component to be disposed at the same angle as the end of the other leg. Because of the previously mentioned procedure of moving the work-supporting means about the hinge pin 26 at such time as the grinding of one component has been completed and a new component is to substituted, the setting of the slide member or depth-controlling member 56 of the depth-establishing device 50 need not be disturbed, and a large number of like components can be ground to a selected length and/or angularity on a very rapid and consistent basis.
It is to be noted that the work-supporting means 120 of FIG. 3 is wider than the work-supporting means 20 of the previous embodiment, and this greater width enables two parallel slots, slots 140 and 142, to be disposed in the means 120, in lieu of the previously-described single slot 42 in the means 20. The slots 140 and 142 are both parallel to the longitudinal centerline 28--28.
As will be seen by an inspection of FIG. 3, a pair of mounting members are utilized for supporting the separate legs of the U-shaped component C, with mounting member 130 being mounted over the slot 140, and mounting member 132 being mounted over the slot 142. The underside of both of these mounting members is equipped with a pair of threaded holes, which are intended to receive bolts 144 inserted through the respective slots 140 and 142. As is obvious, the heads of these bolts are large enough as not to be able to pass through the slots, so it is readily possible to tightly affix these mounting members to the work-supporting means 120.
Supported on the mounting member 130 is a device 134 in the nature of a collet, and supported upon the mounting member 132 is a device 136 in the nature of a collet, with these devices each being of a size to receive one leg of a U-shaped component to be ground. By virtue of the provision of longitudinally extending slots 140 and 142, the user, by loosening the bolts 144, can readily adjust the relationship of the mounting members 130 and 132 as well as the respective collets to the forward edge of the work-supporting means 120. Also, it is readily possible for the user to entirely remove the collet-like members 134 and 136, and to substitute collets of a different internal diameter.
Inasmuch as a dual axis component such as a U-bolt cannot rotate during the time it is being ground, we do not ordinarily find it necessary or desirable to use a bushing means of the type described in conjunction with FIG. 1a, which of course involved a needle bearing 36 receiving a bushing 38. However, if the construction of FIG. 1a for some reason was desired in conjunction with the embodiment of our invention shown in FIG. 3, we could of course substitute the previously-described bushing means in lieu of the collet-like members 134 and 136.
We are aware of the fact that not only may the legs of one U-shaped member be of a different wire diameter than the legs of another U-shaped member, but also the legs of one U-shaped member may be spaced a different distance apart than the legs of another U-shaped member. To that end we may provide orthogonally placed slots adjacent a forward portion of the work-supporting means 120, so that the user may move one collet toward or away from the other collet in order to accommodate a particular U-shaped member. In FIG. 5 we show typical orthogonally placed slots of a suitable type.
It is important to note that we cause the ends of the U-shaped component illustrated in FIG. 3 to protrude beyond the forward edge of the work-supporting means 120. This arrangement makes it readily possible for the user to bring these ends into contact with the bench grinder or belt grinder in the general manner depicted in FIG. 4, so that the ends can be ground to a selected angle, which may, for example, be an angle of 13°.
In the same manner described in conjunction with the earlier figures, we may utilize in FIG. 3, a depth-establishing device 50 of the previously-described type, which of course involves the mounting device 52, the collet member 54, the slide member or depth-controlling member 56 and the tightening device 62. It will be noted in FIG. 3 that we have shown the collet 54 partially broken away in order to reveal internal detail, such as the threads 64 on the tightening device 62. In FIG. 3 we have also shown the member 52 in the vicinity of the spring biased latch pin 24 broken away in order to reveal that the pin 24 is biased by a compression spring 60 that normally biases the latch pin outwardly, in the direction toward the latch member 23. A suitable shoulder 61 on the aft end of the spring biased latch pin 24 prevents it from being entirely expelled from the mounting device 52.
Extending through the hollow central portion of the compression spring 60 is a shaft member 65 of elongate construction, which is affixed in a right-angle relationship to handle member 66. The handle member 66 is configured so as to be easily grasped by the user, and this handle is visible in FIGS. 1 and 2 as well as in FIG. 3.
As is apparent, this arrangement readily enables the user, by grasping the handle 66, to pull the latch pin 24 against the bias of the compression spring 60 for a sufficient extent as to permit the latch member 23 to move past the latch pin 24. As a result of this, the work-supporting means or device 20 is enabled to drop down into the general position depicted in FIG. 2.
It is to be noted from FIG. 2 that the undersurface of the latch member 23 is angled in a manner similar to the angling of the movable portion of a conventional door latch, so as the user moves the work-supporting means 20 upwardly, subsequent to the insertion of the new component to be ground into the collet, the angled undersurface of the latch member 23 readily moves past the latch pin 24. By our utilization of the compression spring 60, the latch pin 24 automatically resumes the outwardly-extending position after the latch member 23 has moved past the pin 24, in which outwardly-extending position the latch pin 24 normally engages the latch member 23 and holds the work-supporting means 20 firmly in the operational position in which the base member 12 and the work-supporting means 20 are caused to reside in substantially planar relationship.
Recalling the depth-establishing device 50, it should be noted in FIG. 3 that the enlarged member 58 disposed on the end of the depth-controlling member 56 is clearly of a size large enough to contact the end of a U-bolt of a wide range of different sizes, thus to assure the ends of each U-bolt extending for a consistent distance beyond the respective collet, into contact with the grinding means.
On the centerline 28--28 in FIG. 3, we show a hole 178 into which a bolt concerned with the support of the protractor 170 of FIGS. 4 and 5 can be inserted.
Turning now to a detailed consideration of FIG. 4, it will be seen that we have shown a device of the previously-described type in which a work support WS shown in full lines is disposed in an angled relationship to the grinding means G. In this particular instance the grinding means G is a belt, but we are not limited to this, and another type of grinding means could in many instances be used equally well. The surface S in FIG. 4 represents the bench or work table or mounting means upon which the grinding device is mounted.
By virtue of the fact that in FIG. 4, the positioning rod 88 has been extended for a lesser distance outwardly than the positioning rod 84, when the forwardmost tips or ends of these rods have been brought into contact with the surface S, this positions our hand held tool such that the leg of the U-shaped component nearest the positioning rod 88 such that it can be extensively ground away, whereas the leg of the U-shaped component nearer the positioning rod 84 will remain significantly longer. Importantly, the tips of both of these legs will be ground at the same angle, making it a relatively simple manner to create a large number of substantially identical U-shaped members that could be welded at a specified angle to a mounting surface. An example of this might be the rack of a dishwasher or other type of power washer, wherein it was desirable to have U-shaped members mounted at a prescribed angle to the rack, rather than being mounted in a vertical relationship to the rack. Our novel arrangement makes it a relatively simple matter for a user to create a large number of U-shaped members of identical length and configuration, with the tips of both of the legs of all of the components residing at the same angle to the centerline of the legs of the U-shaped components.
We obviously are not limited to an arrangement for grinding the legs of a U-shaped component to unequal lengths, for by disposing the work support WS in a perpendicular relationship to the grinding means G, as shown in dashed lines in FIG. 4, the legs of the U-shaped component will be ground to an equal length, and the ends of the legs will be square. In this latter instance, however, both of the positioning rods 84 and 88 should be set to the same length, so that the outermost tips of the rods 84 and 88 will both contact the surface S in a perpendicular relationship, and thus serve to hold the workpiece to be ground in a perpendicular relationship to the grinding means G.
Turning now to FIG. 5, we have shown an embodiment in which essentially the same depth-establishing components are utilized, involving for example the slide member or depth-controlling member 56 and the enlarged, component contacting member 58; the same hinge pin 26; and the same latching means, involving the latch member 23 and the spring biased latch pin 24. The embodiment of FIG. 5 differs, however, in the use of a substantially larger work-supporting means 150 that we prefer to utilize in order that comparatively large U-shaped components can be accommodated. In accordance with this embodiment, a pair of slots 152 and 154 are provided in a perpendicular relationship to the slide member or depth-controlling member 56 of the depth-establishing device 50 that we use. In other words, the slots 152 and 154 extend laterally rather than longitudinally, and are in an orthogonal relationship with the centerline 28--28. Because the mounting members 160 and 162 are movable laterally along the slots 152 and 154, the collets 164 and 166 carried by the mounting members 160 and 162 can be moved together or apart, so as to accommodate the particular width of the U-shaped component whose ends are to be ground. Suitable screws extending upwardly through the slots 152 and 154 and entering the underside of the members 160 and 162 in a threaded relationship are responsible for securing the members 160 and 162 and their respective collets in a fixed relationship, so that a large number of successive U-shaped members of precisely the same basic configuration can be ground.
As before, the preferred depth-establishing components including the slide member or depth-controlling member 56 and the enlarged, component contacting member 58 function to prevent "retreat" of the U-shaped component during the time that its ends are being ground.
Also depicted in FIG. 5 is a protractor 170 that is rotatably mounted upon a mid portion of the work-supporting means 150, with the pivot point for this protractor being located on the longitudinal centerline 28--28 of the work-supporting means 150. We utilize a large-headed pin 172 for rotatably securing the protractor in the desired relationship to the work-supporting means 150, with the lower end of the pin 172 being inserted into the previously-mentioned hole 178 visible in FIG. 3. We utilize an index mark 174 on the longitudinal centerline 28--28, at a location between the hole 178 and the hinge pin 26, which index mark coincides with the 90° mark of the protractor 170 when the protractor is in the "squared" or non-angled relationship illustrated in FIG. 5. A suitable locking device such as a lock nut or wingnut 176 threadedly engages the threads located on the lower end of the pin 172, in the manner shown in FIG. 5a, so that when the user tightens the wingnut or lock nut 176, the protractor is held firmly in a desired relationship to the work-supporting means.
As is obvious, when the protractor is positioned such that the 90° mark of the protractor is in coincidence with the index mark 174, the straight edge 180 of the protractor 170 is perpendicular to the longitudinal centerline 28--28 of the tool 10. By way of example, when the protractor is moved with respect to the work-supporting means such that the 60° mark on the protractor coincides with the index mark 174, the straight edge 180 of the protractor will be at a 60° angle with respect to the centerline 28--28.
In FIG. 4, our hand-held tool depicted in dashed lines is in a 90° relationship to the grinder G, with of course the straight edge 180 of the protractor being in a parallel relationship with the edge S of the grinder bench when the 90° mark on the protractor coincides with the index mark 174.
Our hand held tool 10 may be turned to the left or right of a line perpendicular to the grinder G, depending on which leg of the U-bolt, for example, is desired to be longer.
It should now be clear that our novel arrangement makes it unnecessary for an operator having to guess when the legs of a multi-axis component have been ground to a specified length and angularity, for it is apparent that we are able to rely upon the individually adjustable positioning rods 84 and 88 being adjusted to lengths appropriate in order that the work-supporting means and the work-clamping device will hold the workpiece in a preselected angular relationship to the rotary grinder, belt grinder, or other such grinding means.
It was earlier explained that it would be quite undesirable to have to change the positioning of the depth-controlling member 56 just to permit a freshly-ground component to be removed, so that a new, unground U-shaped component can be inserted into the collets 134 and 136, or the collets 164 and 166. The setting of the depth-controlling member 56 manifestly should not be disturbed inasmuch as it is the consistency of the location of the depth-controlling member 56 and the member 58 with respect to each U-shaped component that assures that both legs of each successive U-shaped component will be ground to a prescribed length and angle. Therefore, instead of any other arrangement, we have provided the hinge arrangement utilizing the hinge pin 26, as was described at length in conjunction with the embodiment of FIGS. 1 and 2.
It should already be clear from the illustration in FIG. 3 with regard to the release of the latch pin 24 that at such time as a freshly ground U-shaped component C is to be removed, the user pulls the handle member 66 to release the latch member 23 such that the work-supporting means 120 can rotate downwardly about the hinge pin 26 with respect to the base member 12, with this causing the U-shaped member C to move out of contact with the slide member or depth-controlling member 56 and the enlarged end member 58, which remain in their same positions. This makes it quite easy for the user to remove the freshly ground U-shaped component from the collet members 134 and 136, and to quickly insert the next U-shaped member to be ground.
Similarly, in the embodiment of FIG. 5, upon the work-supporting means 150 being released to pivot downwardly about the pivot pin 26, it becomes relatively easy to remove the freshly ground U-shaped component from the collet members 164 and 166, and to immediately insert the next U-shaped member to be ground.
It should also be clear that the slide member or depth-controlling member 56 and the enlarged, component contacting member 58 prevent a U-shaped member from "retreating" during the grinding operation, thus assuring that each successive U-shaped member will be of the same size and the same configuration as the previous ones.
The operation of our multipurpose tool is as follows:
Presuming for example that the end of a component or workpiece is to be ground to an angle of 26°, the user loosens the locknut or wingnut 176 of FIG. 5a, so that the protractor 170 may be rotated away from the 90° mark in the desired direction. After a particular point on the graduated, curved edge of the protractor 170 has been aligned with the index mark 174, the protractor is locked in the new position by tightening the locknut 176.
The tightening means 90 and 92 are now loosened, permitting the positioning rods 84 and 88 to be readily adjusted in a lengthwise manner. The straight edge 180 of the protractor 170 is now brought into a parallel relationship with the edge S of the grinder bench. This can usually be accomplished quite well by eye, but if particular accuracy is involved, this visual alignment can be followed up by the use of a ruler for measuring the distance from the edge 180 of the protractor to the edge S of the bench. When the distance from one end of the protractor edge 180 to the adjacent edge S of the bench, is the same as the distance from the other end of the edge 180 to the adjacent edge S, it can be concluded that the straight edge 180 of the protractor is parallel to the edge S of the bench.
The forwardmost or active ends of the positioning rods 84 and 88 are now brought into firm contact with the edge S of the bench, after which the tightening device 90 is utilized to lock the positioning rod 84, and the tightening device 92 is utilized to lock the positioning rod 88. In this way the positioning rods 84 and 88 are secured in positions reflecting the desired angularity of the grinding operation to take place. A recheck of the positioning of the edge 180 of the protractor 170 with respect to the edge S can now be undertaken if desired.
The protractor 170 no longer needs to be mounted on the member 120 or 150, so it can be removed by loosening the lock nut or wingnut 176, and set aside for the next use.
The grinding can now proceed, with the active ends of the positioning rods 84 and 88 continuing to remain in contact with the edge or surface S, thus to assure that the grinding of each successive component will be accomplished in an accurate manner.
As is obvious, when the ends of a component different from the preceding components are to be ground, the user or operator can go through the procedure of reinstalling the protractor 170, and then rotating the protractor with respect to the mark 174 until the desired angularity of the edge 180 has been achieved. The operator then proceeds to align the straight edge 180 of the protractor with the surface or edge S. When this has been accomplished, the active ends of the positioning rods are brought into contact with the surface or edge S, and the positioning rods 84 and 88 are locked in the adjusted positions. The protractor can now be removed and set aside for future use, so that grinding of the ends of the components or workpieces can proceed.
We are not to be limited to any particular constructional materials, but tool steel is quite satisfactory in most instances, although in certain other instances, it is desirable to make the components of stainless steel or some other non-rusting, noncorrosive material.
Inasmuch as the protractor 170 is not normally subjected to heavy use, it can be made of aluminum, which is a considerably less expensive material to utilize for such an application.
|
A device for supporting a workpiece for being ground to size by the use of a grinding means, comprising a base member having a work-supporting means operably associated therewith. The base member supports the work-supporting means by a hinge member, with the base member and the work-supporting means normally being in an aligned relationship, but with the hinge member enabling the relationship of the work-supporting means to the base member to be angularly modified on occasion. The work-supporting means has thereon a work-clamping device constructed and arranged to hold a workpiece in a selected position, such that a portion of the workpiece held in the work-clamping device can be brought into direct contact with the grinding means. A depth-controlling member operably mounted upon the base member is positioned to normally contact a workpiece held in the work-clamping device. The position of the depth-controlling member is adjustable, so that the amount of material to be removed from the workpiece can be selectively controlled. A latch member under control of a user and operatively associated with the hinge member makes it readily possible to move the work-supporting means and its work-clamping device out of the aligned relationship, thus enabling an already-ground workpiece to be removed from the work-clamping device and an unground workpiece substituted, without altering the position of the depth controlling member.
| 1
|
BACKGROUND OF THE INVENTION
Counterbatten systems are used with tile roof installations to elevate the roof tiles above the roof deck surface. By elevating the roof tiles, water is prevented from gathering under and/or around the roof tiles, which protects the roof deck from damage, and the air space created between the roof deck and the roof tiles facilitates ventilation of the roof.
Counterbatten systems are typically created by fastening wood strips, which are called vertical battens, in a vertical direction up the roof at 16″ or 24″ on center onto the roof decking. Horizontal, or anchor, battens are then fastened directly onto these vertical battens. The size of the batten strips will vary according to spacing and load factors, but the minimum dimensions are typically ⅜″ thick for the vertical strips and nominal 1″×3″ for the horizontal strips. By installing the horizontal battens onto the vertical battens, nail penetrations into the roof decking are minimized, and the nails that penetrate the roof deck are less likely to be exposed to water because they only penetrate the vertical strips that run parallel to water flow.
Although such counterbatten systems provide some advantages to tile roof installations, they may be time consuming to install. U.S. Pat. No. 6,536,171 discloses an elevated batten system solution in which pads or blocks are attached to the underside of the horizontal batten strips prior to installation, and these pads serve the function of the vertical strips of the counterbatten system. By not having to install the vertical strips, the installation may progress more quickly and with less materials. This elevated batten system uses diamond-shaped pads, which diverts the flow of any water to either side of the pad. Such systems require relatively accurate orientation and attachment of the pads relative to the strips, which can increase the amount of time and cost it takes to manufacture the batten strips. In addition, inconsistencies in the height of the batten strips at each pad may be introduced when the pads are attached to the horizontal strips if a fastener, such as a nail or staple, is not inserted into the pad properly or if varying amounts of adhesive are used to couple the pads to the horizontal strips.
Thus, there remains a need in the art for an improved elevated batten system.
SUMMARY OF THE INVENTION
Various embodiments of the invention provide an improved elevated batten assembly for use atop an inclined roof supporting surface and for supporting tiles above the inclined roof supporting surface. The elevated batten assembly comprises (1) an elongate horizontal batten strip that has an underside for generally facing the inclined roof supporting surface and (2) a plurality of support pads that are spaced apart and coupled to the underside of the batten strip. The support pads each include opposing first and second sides, wherein each of the first and second sides comprises a substantially flat surface. The first side is coupled adjacent to and substantially in planar contact with the underside of the batten strip. In addition, the second side of each support pad is configured for being substantially in planar contact with the inclined roof supporting surface, the support pads support the batten strip above the inclined roof supporting surface, and each of the support pads have a cylindrical wall that extends between the first and second sides. According to one embodiment of the invention, the cylindrical-shaped pads do not require orientation relative to the horizontal batten, which may be required when using square or rectangular shaped pads. In addition, the cylindrical wall of the pads deflects water around the pads to prevent pooling, and the first and second sides of the pads allow the pads to fit substantially flush against the underside of the horizontal battens and the roof deck surface, which prevents debris and other materials from getting caught between the pads and the batten and/or the roof deck and prevents damming that can result in roof leaks or premature deterioration of the underlayment, battens, and/or fasteners.
According to other various embodiments of the invention, an elevated batten assembly for use atop an inclined roof supporting surface and for supporting tiles above the inclined roof supporting surface is provided. The elevated batten assembly comprises (1) an elongate horizontal batten strip that has an underside for generally facing the inclined roof supporting surface and (2) a plurality of support pads that are spaced apart and coupled to the underside of the batten strip. The support pads each include opposing first and second substantially flat side portions, and the first substantially flat side portion of each support pad is coupled adjacent to and substantially in planar contact with the underside of said batten strip. The second substantially flat side portion of each support pad is configured for being substantially in planar contact with the inclined roof supporting surface. In addition, the support pads support the batten strip above the inclined roof supporting surface, and each of the second substantially flat side portions defines a depressed portion that is configured for receiving a fastener for coupling the support pad to the horizontal batten strip. According to one embodiment, installing the fastener in the depressed portion can prevent inconsistencies in the height of the horizontal batten along the length of the batten due to an improperly attached fastener.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of an elevated batten assembly 10 according to various embodiments of the invention.
FIG. 2A is a lower plan view of the elevated batten assembly 10 assembled according to a first configuration, according to various embodiments of the invention.
FIG. 2B is a lower plan view of the elevated batten assembly 10 assembled according to a second configuration, according to various embodiments of the invention.
FIG. 3 is schematic diagram of the flow of water 13 around an exemplary pad, according to various embodiments of the invention.
FIG. 4A is a lower plan view of a support pad having a depressed portion according to various embodiments of the invention.
FIG. 4B is a side elevational view of the support pad shown in FIG. 4A .
FIG. 5 is a pictorial view showing the outline of an exemplary group of tiles 100 installed atop the elevated batten assembly 10 according to various embodiments of the invention.
FIG. 6 shows two configurations of batten assemblies 10 a , 10 b stacked relative to each other such that the pads of the two batten assemblies have nest between each other in an alternating fashion, according to various embodiments of the invention.
FIG. 7A is a lower plan view of an assembled elevated batten assembly according to an alternative embodiment of the invention.
FIG. 7B is a perspective view of two of the assembled elevated batten assemblies shown in FIG. 7A stacked together according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The elevated batten system according to various embodiments of the present invention is designed to eliminate the need to install the vertical and horizontal battens in separate steps. In particular, pads 14 are attached to the underside of the horizontal battens 12 at the lumber mill or other assembly facility. These pads serve the function of spacing the horizontal batten strips above the roof deck surface, which was served by the the vertical strips used in the prior art counterbatten system described above, but the pads provide a more efficient method of installation and reduce the amount of materials used during installation.
According to various embodiments of the invention, the pads may be cylindrical-shaped or rectangular or square-shaped and made from wood (e.g., plywood) or another suitable material such as rubber, plastic (e.g., HDPE) or other polymer, and/or recycled materials. The pads are attached at pre-defined increments along horizontal batten strips with a suitable fastener (e.g., staples, adhesive, or nails) prior to bundling and shipping from the assembly facility. The pre-defined increments and the dimensions of the pads and the horizontal strips may depend on the load conditions and/or weather conditions to which the roof will be subject. The elevated batten system according to various aspects of the invention may then be installed horizontally along a roof such that the pads are disposed immediately adjacent the roof deck surface or underlayment. In addition, the pre-assembled elevated batten system can be used with any profile of roof tiles and in a variety of load conditions, according to various embodiments. Furthermore, in a particular embodiment, the battens may be treated with pressure treating or other weather resistant properties as needed.
In a particular embodiment, the pads 14 are cylindrical and have a diameter of about 1½″ and a thickness of about ⅜″. The pads are installed on one side of the horizontal batten 12 at 12 ″ intervals using a staple or other suitable fastener. The pads elevate the horizontal batten above the roof deck by a height substantially equal to the thickness of the pads 14 and provide adequate support for the horizontal batten 12 to prevent deflection.
Elevating the battens 12 allows for water and debris to pass freely beneath the battens and allows improved airflow above the roof support surface, which reduces heat gain in the roof system and reduces cooling costs. In addition, unlike rectangular or square-shaped pads, which may require orientation into a diamond-shape relative to the horizontal axis of the horizontal batten prior to attachment to the horizontal batten, cylindrical-shaped pads do not require orientation relative to the horizontal batten. Furthermore, the cylindrical walls of the pads deflect water around the pads to prevent pooling, and the flat sides of the pads allow the pads to fit substantially flush against the underside of the horizontal battens and the roof deck surface, which prevents debris and other materials from getting caught between the pads and the batten and/or the roof deck and prevents damming that can result in roof leaks or premature deterioration of the underlayment, battens, and/or fasteners. For example, as shown in FIG. 3 , water and/or debris 13 flow around the pad 14 .
In other various embodiments, the pads 14 have rectangular, square, or other polygonal shapes, have thicknesses greater than or less than ⅜″ depending on the height requirements of the installation, and may be installed at alternative selected intervals (e.g., 16 inches on center, 24 inches on center, or other selected distances).
According to a particular embodiment of the invention which is shown in FIGS. 2A and 2B , the pads 14 are spaced from the ends of the horizontal battens in at least two configurations. A first configuration 10 a is shown in FIG. 10A and a second configuration 10 b is shown in FIG. 10B . The pads 14 a in the first configuration 10 a are positioned closer to the end of the horizontal batten 12 a than the pads 14 b in the corresponding second configuration 10 b . The pads 14 b in the second configuration 10 b are spaced from the end of the horizontal batten 12 b such that a pair of battens 10 a , 10 b may be stacked with their respective pad sides cofacing, with the pads nesting between each other in an alternating fashion, such as shown in the embodiment in FIG. 6 . In addition, this alternating configuration provides for more efficient stacking and shipping and provides solid support at each end of adjoining battens. The batten assemblies 10 a , 10 b can be aligned and bundled with plastic strapping.
In an alternative embodiment, which is shown in FIGS. 7A and 7B , the pads are spaced from the ends of the battens to minimize the risk of splitting during the attachment to the roof. In a particular embodiment, the pads are positioned about three inches from each end of the batten, and when stacked, as shown in FIG. 7B , the ends of the battens are slightly staggered with respect to the each other.
The horizontal batten strips 12 are manufactured from wood, according to various embodiments of the invention. In a particular embodiment, the wood used for the strips 12 is Douglas Fir lumber, which is a strong, construction-grade material. Furthermore, the horizontal strips may be nominal about 1″×about 3″ or about 1″×about 2″ lumber and cut into about 4 foot or about 8 foot strips, according to various embodiments. The thickness of the lumber may be between about ⅜″ and about 1″ (e.g., about ¾″) and the height of the lumber may be between about 1″ and about 3″ (e.g., about 1½″ or about 2½″), according to various embodiments of the invention.
In addition, in a particular embodiment, twenty four 4 foot strips that are assembled with the support pads are bundled together and strapped, and each bundle provides a sufficient number of battens for installing approximately one square (100 square feet) of roofing tile. In another embodiment, twelve 8 foot strips assembled with support pads are bundled together and strapped, and each bundle provides a sufficient number of battens for installing approximately one square (100 square feet) of roofing tile. Furthermore, according to various embodiments, the strips 12 may be marked on the side of each strip 12 opposite the side to which the pads 14 are attached with to indicate nailing points, making installation easier for the roof system installers.
In other various embodiments such as those embodiments shown in FIGS. 1 , 4 A, and 4 B, the pads 14 comprise two substantially flat sides that are opposite each other. The first substantially flat side 16 a is installed adjacent the horizontal batten 12 , and the second substantially flat side 16 b is installed adjacent the roof deck surface.
In a particular embodiment which is shown in FIGS. 4A and 4B , a depressed portion 15 is further defined in at least one of the first and/or second substantially flat sides 16 a , 16 b . According to one embodiment, the depressed portion 15 is defined in the second substantially flat side 16 b and a fastener, such as a staple, nail, or screw, is engaged into the depressed portion 15 to attach the pad 14 to the horizontal batten 12 . The depth of the depressed portion 15 is dimensioned such that the head of the fastener when attached to the pad 14 and the horizontal batten 12 does not extend past the plane in which the substantially flat side 16 a , 16 b lies (e.g., the depth of the depressed portion 15 is at least as deep as the thickness of the head of the fastener and may further include some additional tolerance to provide for variations in manufacture of the fasteners, according to one embodiment), and the width of the depressed portion 15 is at least as wide as the width of the head of the fastener.
Installing the fastener in the depressed portion 15 prevents inconsistencies in the height of the horizontal batten 12 along the length of the batten 12 due to an improperly attached (e.g., protruding) fastener, for example. In addition, according to various embodiments such as the embodiment shown in FIG. 5 , the horizontal battens 12 are secured to the roof deck surface 200 using fasteners that are installed into the surface of the battens 12 opposite the underside to which the pads 14 are attached.
By installing the fasteners 20 through the batten 12 and the pad 14 , according to one embodiment, a hole in the roof deck surface 200 made by the fastener is protected from water and debris by the edges of the pads' 14 substantially flat sides 16 b . In addition, the depressed portion 15 allows for flush and non-flush type fasteners to be used to secure the pads 14 to the battens 12 . Upon installing the batten assemblies 10 to the roof deck surface 200 , tiles 100 may be installed over the batten in a conventional manner on the upwardly facing side of the battens.
CONCLUSION
Although this invention has been described in specific detail with reference to the disclosed embodiments, it will be understood that many variations and modifications may be effected within the spirit and scope of the invention as described in the appended claims.
|
Various embodiments of the invention are directed to an elevated batten system that includes a horizontal batten strip to which cylindrical-shaped pads are coupled. The pads elevate the horizontal batten strip above the roof deck surface, preventing water and debris from gathering on the roof deck surface and eliminating the need to install the vertical and horizontal battens in separate steps. Other various embodiments of the invention are directed to an elevated batten system that includes a horizontal batten strip to which pads are coupled that define a depressed portion. The depressed portion receives a fastener for coupling each pad to the horizontal batten strip, and in some embodiments, prevents irregularities in the height of the horizontal batten strip relative to the roof deck surface when installed on the roof deck surface.
| 4
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a grout impregnation method and more particularly to a method for impregnating two-part curable grout, for example a composite grout comprising water glass and carbonated water or carbon dioxide gas, into soil to stabilize the earth.
2. Related Arts
In an early grout impregnation method, a single-liquid grout was used. Thereafter, various improvements have been introduced into this method. For example, two liquids, which are curable when they react each other, are used as a grout (two-part curable grout) in such a manner that they are mingled in a Y-shaped pipe provided at a base portion of an injection tube. Recently, a further improvement has been made and a method has become predominant in which the two liquids are mingled and mixed within the injection tube and the resulted grout is injected into the earth.
Although various kinds of two-part curable grouts have been known, a grout containing water glass (sodium silicate) is most widely used today because it does not pollute the soil. Water glass may be used with a reactant such as an acid or a salt of the acid.
Water glass may alternatively be used with a reactant of carbonated water to provide a grout to be impregnated into the earth for stabilization of the soil. This is disclosed, for example, in Japanese Kokai No. 53-74709.
Carbon dioxide gas has such an advantage that it is less expensive and harmless. However, to prepare carbonated water by absorbing carbon dioxide gas in water and to use the resultant carbonated water with water glass as a grout, there is a problem to be solved as will be described later. By this reason, this grout has not been put into practical use heretofore.
Such a reaction is given by:
2H.sup.+ +CO.sub.3.sup.2- +Na.sub.2 O nSiO.sub.2 →Na.sub.2 CO.sub.3 +H.sub.2 O+nSiO.sub.2
Thus, when carbonated water and water glass are impregnated into the soil after their mixing, silica and sodium carbonate are produced in the soil to solidify flimsy portions of the earth, stabilizing the same.
In the conventional grout impregnation using a two-part curable grout, it has been considered essential to mix the two liquids supplied in equal amounts under equal pressures. The conventional grout impregnation of this type, in effect, is carried out by mixing the two liquid-parts of equal amounts under equal pressures.
However, when carbonated water is preliminarily prepared and supplied to the injection tube, carbonated water is liable to be separated into water and carbon dioxide gas if the pressure within the tube is not high enough, and can not be reacted sufficiently with water glass. On the other hand, when it is required to prepare carbonated water at an execution site, water and carbon dioxide gas must be contacted under a high pressure in a closed vessel to obtain carbonated water of high concentration. By this reason, carbonated water should inevitably be led to the injection tube under a high pressure. In addition, the pressure within the dissolving vessel for preparing carbonated water should be increased to shorten a gelling time of the grout as shown in FIG. 10.
If carbonated water is thus supplied into the injection tube under a high pressure and water glass is supplied thereinto under a lower pressure, the flow of carbonated water become dominant within the tube and the two liquids are not reacted sufficiently.
A valve provided after the mixing of two liquids has been known. However, the known valve after the mixing of the liquids is a check valve for preventing back flow of soil into the injection tube after injection of the grout into the soil, and not a valve for holding a pressure of the mixing section. A valve is not provided, in a conventional technique, upstream the mixing section.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to provide a grout impregnation method which allows components of a curable grout to contact, mix and react with each other sufficiently and positively to prepare the grout which is capable of developing sufficient strength.
It is another object of the present invention to provide a grout impregnation method which enables sufficient mixing of materials when one material is supplied under a higher pressure than the other in such a case of carbonated water or cabon dioxide gas and water glass used as components of a two-part curable grout.
SUMMARY OF THE INVENTION
The present invention features a grout impregnation method which uses an injection tube for contacting and mixing therein different kinds of materials supplied separately thereinto to prepare a grout and impregnates the prepared grout into the earth through an injecting opening provided at a tip end of the tube, which method is characterized in that: a first pressure-holding valve is provided within a higher-pressure path for one of the materials which is supplied under a higher pressure, a mixing section is provided downstream said first pressure-holding valve but in the vicinity thereof for letting said one of the materials contact and mix with another one which is supplied under a lower pressure, and a second pressure-holding valve is provided downstream the mixing section; said one of the materials is passed through said first pressure-holding valve, which reduces the pressure of said one of the materials, and then contacted and mixed with said another one at the mixing section; the contacting and mixing is carried out under a pressure exceeding atmospheric pressure and determined by the second pressure-holding valve; and the grout resulting from said contacting and mixing and passed through the second pressure-holding valve is impregnated into the earth through the injecting opening of the tube.
The present inventors have conducted various laboratory tests and pilot tests to achieve a grout impregnation method using water glass and carbonated water or carbon dioxide gas and found that there are some problems to be solved. Among these is a problem that carbonated water and water glass are impregnated into the earth possibly without being reacted sufficiently, deteriorating the soil stabilizing effect, if they are kept at a high pressure and subjected to a reaction for a sufficient time. More particularly, unless the material liquids are mixed and reacted sufficiently, carbonated water and water glass are separately injected into the earth. Moreover, carbonated water is further separated into water and CO 2 gas. It has been observed that a desired grout is not obtained when the mixing and rection are not sufficient and that CO 2 gas bubbles up from the injecting opening of the tube.
This phenomenon can be explained as follows: when one of the material liquids, for example, carbonated water is supplied under a high pressure and another material liquid, for example, water glass is supplied under a lower pressure, if appropriate valve means are not provided for controlling the pressures and flow rates, carbonated water of a higher pressure becomes predominant in the flow and carbonated water is sprouted from the injecting opening of the tube without being sufficiently contacted, mixed and reacted with water glass. Carbonated water is further separated into carbon dioxide gas and water and carbon dioxide gas spurts out.
With the first pressure-holding valve provided within the path for the higher pressure material leading to the mixing section according to the present invention, the pressure after the first pressure-holding valve is kept lower than the actuation pressure of the valve. At this lowered, substantially equalized pressure, the material is made to contact and mix with the material which has been supplied under a lower pressure at the same supplying rate. As a result of this, the materials can be mixed with each other sufficiently and uniformly.
With the second pressure-holding valve provided between the mixing section and the injecting opening of the tube, the mixing section is held at a pressure substantially the same as the actuation pressure of the second pressure-holding valve. If the second pressure-holding valve is not provided, the pressure of the mixing section is substantially atmospheric. Under this condition, the materials of the grout can not be mixed well. Whereas, if the pressure of the mixing section is kept at 1 kg/cm 2 G or higher, preferably 3 kg/cm 2 G or higher, more preferably 5 kg/cm 2 G or higher, the materials are contacted and mixed with each other in the mixing section at a high pressure and they are mixed uniformly.
To obtain carbonated water of high concentration or a grout of shortened gelling time, the operating pressure within the dissolving vessel (packed absorber) for the preparation of carbonated water should be high as described above. For this reason, it may be possible to provide means for keeping the pressure within the packed absorber high and to provide a pressure reducing valve in a path for carbonated water leading to the injection tube. The mixing section is provided far downstream of the reducing valve for letting carbonated water contact with water glass. In this case, even if carbonated water and water glass may be supplied and mixed under equal pressures, it is not possible to obtain a uniform, homogeneous grout.
In contrast, it has been found that if the mixing section is provided within 2 m, preferably within 1 m, more preferably within 0.5 m from the first pressure-holding valve, the desired mixing of the materials can be attained. The reason of this is not known, but it may be inferred that the pressure of the carbonated water is rapidly reduced when carbonated water passes through the first pressure-holding valve and it is diffused into the flow of water glass.
The inventors have also found that mere contact of the two materials, carbonated water and water glass, is not sufficient to achieve sufficient reaction between them. In this case, carbonated water and water glass are impregnated into the earth separately. Whereas, if the materials are kept to dwell, for a sufficiently long time, within a space limited by and between the first pressure-holding valve and the second pressure-holding valve, sufficient reaction between the materials is attained. To improve the contact and mixing, the contacting and mixing zone may be prolonged. However, the injection tube is formed, in use, by coupling a plurality of tube members into a desired length. Therefore, the length of the tip tube member of the injection tube is limited and can not be lengthened as desired.
In a preferred embodiment of the present invention, a mixing accelerating section may be provided within the injection tube. In the mixing accelerating section, carbonated water and water glass flow a path consisting of at least one reciprocating path segment which is first directed towards the tip and then turns towards the base. Thus, an elongated or extended path length can be attained in a limited length of the tip tube member. As a result of this, sufficient reaction time can be obtained without elongating the tip tube member. This is also advantageous in maintenance and cleaning of the tube.
Before this invention, there has not been known an idea of reciprocating flow of the material mixture in an axial direction of the tube.
The present invention is suitably applied when the supplying pressures of the two materials of the two-part curable grout are different, especially when the ratio in supplying pressure of the higher-pressure material to the lower-pressure material is 1.2 or higher.
The actuation pressure of the first pressure-holding valve is preferably 0.5 times or more and 1.5 times or less the supplying pressure of the material passing through the valve. If the ratio is less than 0.5, the higher-pressure material passing through the first pressure-holding valve becomes too predominant over the lower-pressure material to be mixed with the latter uniformly.
When the desired grout comprises equal parts of two materials, the supplying rates of the liquids should be substantially equal. The ratio in supplying rate between the higher-pressure material and the lower-pressure material is preferably 0.7 to 1.3, more preferably 0.85 to 1.15 to attain uniform and homogeneous mixture. Of course, the above.
The present invention may also be applicable to the reaction between other known two-component system such as the reaction between carbon dioxide gas and water glass or the reaction between cement and water glass.
When the grout used has a shortened gelling time, it is preferred to provide the first pressure-holding valve, the mixing section and the second pressure-holding valve in the tip tube member of the injection tube to prevent clogging of the flow path of the grout due to curing of the grout. However, if a grout of longer gelling time is used, the valves and the mixing section may be provided at more upstream portions of the tube because there is no fear of clogging due to the curing of the grout.
The pressure-holding valve employable in the present invention may be valves biased by springs, or needle valves, or may be orifices. In other words, any kind of means may be employable as far as it operates to hold the pressure of the supplying line of the higher-pressure material, as the first pressure-holding valve or to keep the pressure within the mixing section or function as a check valve, as the second pressure-holding valve. Thus, the word "valve" used herein should be interpreted widely.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a half-sectional view of one form of a tip tube member of an injection tube according to the present invention;
FIG. 2 is a half-sectional view of a principal portion of the injection tube shown in FIG. 1;
FIG. 3 is a front view of a mixing accelerator employable in the present invention;
FIG. 4 is a block diagram showing an entire system for grout impregnation;
FIG. 5 is a perspective view of another form of mixing accelerator;
FIG. 6 is a half-sectional view of another form of a tip tube member of an injection tube employable in the present invention;
FIGS. 7, 8 and 9 are sectional views of other forms of pressure-holding valve; and
FIG. 10 is a diagram showing a relationship between a pressure within a dissolving vessel during the preparation of carbonated water and a gelling time of the resultant grout.
DESCRIPTION OF PREFERRED EMBODIMENTS
The invention will now be described referring to the drawings.
FIG. 4 illustrates an entire system for soil stabilization.
1 is an injection tube which is inserted into the earth E and set there for impregnating grout into an ambient portion of the ground. The injection tube 1 is used in combination with a grout supplying system consisting essentially of a carbon dioxide gas CO 2 source, e.g. a carbon dioxide gas bomb 2, a packed absorber 3, a water source 4, a water-glass tank 5 and a grouting pump 6. Carbon dioxide gas CO 2 from the gas bomb 2 is supplied to the absorber 3, preferably to a lower portion of the absorber 3 through a vaporizer 7 for enhancing vaporization especially in a winter season and a gas flow control valve 8. The absorber 3 has packings 9 such as saddles or Raschig rings packed therein. The absorber 3 further includes a spray nozzle 10 installed at an upper portion thereof for spraying water 4 fed by a pump 11 through a flow control valve 12.
Thus, the carbon dioxide gas and water are brought into contact with each other in the absorber 3 to produce carbonated water. At this time, the packings 9 enhance the gas-liquid contact. The carbonated water thus produced is drawn out from the bottom of the absorber 3 by the double acting pump 6 to be led, for example, into an inner path of the injection tube 1.
It is very crucial to balance the production of the carbonated water with the feed (or consumption) of the carbonated water by the pump 6. For this reason, an upper- and a lower-limit level detector 13U, 13L are provided at a lower portion of the absorber 3 in the present embodiment to control the water flow rate by operating the water flow control valve 12 by an liquid level controller 14 so that the liquid level of the carbonated water is kept between the upper- and lower-limit levels. In addition to the liquid level control, the concentration of carbon dioxide dissolved in the carbonated water is also to be controlled because it influences the reactivity of the carbonated water with water glass. To this end, a pressure detector 15 is provided within the absorber 3. The gas flow is controlled by operating the gas flow control valve 8 by a pressure controller 16 to control the carbonated water concentration.
On the other hand, water glass is drawn up from the tank 5 by a liquid feeding pump 17 and then led, for example, into an outer path of the injection tube 1.
Referring further to FIGS. 1 to 3, the carbonated water CW and the water glass NS are fed to a tip tube member of the injection tube as illustrated in FIG. 1 through a swivel joint (not shown) and a coupling barrel of a known double-tube structure.
The tip tube member comprises an outer pipe elements 20A to 20E within which various members as will be described below are provided.
At a base end portion of the tip tube member, a leading member 30, an intermediate member 31, a connecting member 32 and a trailing member 33 are threadedly engaged with each other and installed inside the tip tube member. The carbonated water CW first enters a first path a1 formed at a center of the leading member 30, passing through a plurality of second paths a2 formed so as to extend from a tip end of the first path a1 slantingly in a radial direction, through a third path a3 defined by a gap between the outer periphery of the leading member 30 and the inner surface of the outer pipe element 20A, and through a fourth path a4 formed so as to extend from a tip end of the third path a3 slantingly to a center of the outer pipe element 20A. The carbonated water CW is then led into a fifth path a5 formed at a central portion of the intermediate member 31 and further led to a sixth path a6 formed inside the trailing member 33, while pushing down a first dwelling or pressure-holding valve 41 which is biased by a spring 34 resting against the trailing member 33.
The water glass NS is introduced into a first path b1 formed by a gap between the outer periphery of the leading member 30 and the outer pipe element 20A and is forced to pass through a plurality of second paths b2 formed in the leading member 30 to extend along the axis thereof to reach a third path b3 formed centrally at the tip end portion of the leading member 30. The water glass then passes through a fourth path b4 within the intermediate member 31 while pushing down a check valve 43 urged by a spring 35 rested against the intermediate member 31 and passes through a plurality of fifth paths b5 formed within an increased diameter portion of the intermediate member 31 to extend along the axis thereof to reach a sixth path b6 formed by a gap between the outer peripheries of the intermediate member 31, the connecting member 32 and the trailing member 33 and the inner surfaces of the outer pipe elements 20A and 20B.
36 is a lock nut for locking the trailing member 33 relative to the intermediate member 32 after the force of the spring 34 is set by screwing the trailing member 33 to set an actuation pressure of the first pressure-holding valve 41. 37 is a guide for the spring 35.
A tip end portion of the trailing member 33 receives a mixing accelerator 50 fitted therein. A valve seat 61 for a second dwelling or pressure-holding valve 42 is disposed next to the tip end of the mixing accelerator 50. The second pressure-holding valve 42 is biased towards the valve seat 61 by a spring 64 resting against a seat 63 which is locked relative to the outer pipe element 20C by a lock nut 62.
The mixing accelerator 50 is fitted closely within the outer pipe element 20B. The mixing accelerator 50 is formed in a columnar shape and is, for example, about 25 cm in length. The mixing accelerator 50 has a groove on the outer periphery thereof. The groove comprises one or more reciprocating flow paths 51, five in the present embodiment. Each of the reciprocating paths is formed of a forward path section directed from a base to a tip and a backward path section returning to the base which communicate with each other. The groove further comprises an extra forward path for finally directing towards the tip end of the injection tube. Therefore, the materials flow along the groove of about 275 cm (25×5×2+25) in total. In general, the mixing accelerating path has a length of 0.5 m or more, preferably lm or more.
As can be understood from the foregoing description, the path system a1 to a6 for the carbonated water CW and the path system b1 to b6 for the water glass NS are separate from each other before the tip end of the trailing member 33. The carbonated water CW and the water glass NS first meet when they enter the mix accelerating path 51 through an entrance recess 52A at a base end of the mixing accelerator 50 after they have passed the tip end of the trailing member 33. These materials thereafter are mixed sufficiently while being subjected to reaction for a sufficient time during their course of flowing through the long mix accelerating path 51. The resultant mixed up grout leaves the mix accelerating path 51 through an exit 52B and enters within the valve seat 61, then passing through grout paths g1 to g5 therein to be injected into the earth E through an injecting opening 70 at the tip end of the injection tube 1.
In this connection, it is to be noted that only two reciprocating paths and one extra forwarding path are shown in section of the mixing accelerator 50 in FIGS. 1 and 2 to simplify the illustration.
As described above, the mixing accelerator 50 having the reciprocating paths can provide a desired length of mixing and reacting time prolonged as compared with that of the length of the mixing accelerator 50. Thus, the materials, the carbonated water and the water glass, can be mixed sufficiently and it can be avoided that the materials are impregnated as they are separate. Ordinary two-part curable grouts other than that specified herein may be used after simple mixing of the two parts. However, carbonated water is not easily mixed with water glass. For this reason, the mixing acceleration arrangement employed in the present embodiment is very effective for the grout consisting of carbonated water and water glass.
To handle carbonated water and water glass which are difficult to mix, it is desirable, as well as to prolong the reaction time, to mix them under a relatively high pressure within a mixing section (chamber), for example 1 kg/cm 2 G or higher, preferably 3 kg/cm 2 G or higher, more preferably 5 kg/cm 2 G or higher.
To this end, the first pressure-holding valve 41 and the second pressure-holding valve 42 are provided before and after the mixing accelerator 50 in this embodiment. More specifically, to keep the mix accelerating path 51 at a relatively high pressure, carbonated water is supplied to the first pressure-holding valve 41 under a pressure of 5 kg/cm 2 G or higher, preferably 10 kg/cm 2 G or higher, more preferably between 15 kg/cm 2 G and 40 kg/cm 2 G. In addition, the actuating pressure of the second pressure-holding valve 42 is set to be 1 kg/cm 2 G or higher, preferably 3 kg/cm 2 G or higher, more preferably 5 kg/cm 2 G or higher. With this arrangement, the pressure within the mixing section is kept at a pressure corresponding to the actuating pressure of the second pressure-holding valve 42. With respect to water glass NS, the check valve 43 is set so that it may operate when the dynamic pressure of the water glass acts on the valve. The pressure for supplying the water glass is 1.5 to 10 kg/cm 2 G, preferably 3 to 7 kg/cm 2 G.
In a conventional injection tube, a check valve operates when a dynamic pressure is applied, whereas in this embodiment, the pressure-holding valves 41 and 42 are provided to keep the mix accelerating section between the pressure-holding valves 41 and 42 at a desired high pressure, which is novel in the grout impregnation method.
The mixing accelerator 50 of the present embodiment may be replaced by a mixing accelerator 50' having a helical mix accelerating path 51'. In this case, the helical path consists of two helical path segments disposed alternatingly. These helical path segments communicate each other at a turning point 53' and one is directed to a tip end and another returns to a base. The returning path segment further communicates at the base end thereof with a center path 54' which opens at a tip end 55 thereof.
The water glass and the carbonated water may alternatively be brought- into contact with each other at a position upstream from the mixing accelerator 50 as illustrated in FIG. 6. In this case, the water glass NS passes through a seventh path b7 formed in a wall of the connecting member 32 and is brought into contact with the carbonated water CW at a position adjacent to and downstream from the first pressure-holding valve 41.
In this connection, it is to be noted that a plurality of mix accelerators may be combined in an axial direction of the tube. The injecting opening 70 may be set back from the tip end face of the injection tube 1. The injection tube 1 may have a triple-flow path structure. In this case, two flow paths may be used for grout feeding and one flow path is used for water feeding at a time of boring.
Although the first and the second pressure-holding valve and the mixing section are provided within the injection tube, it may alternatively be provided outside of the tube as illustrated in FIG. 7. In FIG. 7, water glass NS supplied from a pump through a hose enters a mixing chamber 102 provided at an intersection, while pushing down a check valve 101. On the other hand, carbonated water CW supplied from a pump through a hose pushes down a check valve 103 and then passes through a space between a conical portion of a first pressure-holding valve 104 and a valve seat 105 to enter the mixing chamber 102, where the carbonated water is brought into contact with the water glass and mixed therewith. When the pressure for supplying the carbonated water is changed, an adjusting handle 106 may be operated to change a gap between the conical portion of the first pressure-holding valve 104 and the valve seat 105 to maintain the pressure determined by the first pressure-holding valve. A reacting chamber 108 having a long pipe path 107 is connected to the mixing chamber 102. The liquids are allowed to react sufficiently when they flow through the reacting chamber 108. A second pressure-holding valve 109 is provided downstream of the reacting chamber 108. The grout passes through the second pressure-holding valve 109 and is fed to a supplying hose 111 through an exit 110 and supplied to an injection tube lA. An actuating pressure of the second pressure-holding valve 109 is adjustable by a control handle 112.
FIG. 8 illustrates another form of a pressure-holding valve system which is identical with that of FIG. 7 except that a first pressure-holding valve 104A is urged by a spring 113, the force of which is controllable by the control handle 106. In this case, a seat 104B for the spring 113 is displaced.
FIG. 9 illustrates a still another form of a pressure-holding valve system in which a first pressure-holding valve 115 and a check valve 116 are provided within a T-shaped casing 114. Carbonated water CW passes through a through hole 115a of the first pressure-holding valve 115 and pushes down the first pressure-holding valve 115 against the action of the spring 117. The carbonated water CW then passes through a long, narrow flow path 118 to reach a mingling chamber 119. The water glass NS passes through a through hole 116a to push down a check valve 116 and is then combined with the carbonated water CW at the mingling chamber 119. The mixed liquids are then guided through a mix accelerating path (not shown) to reach a second pressure-holding valve (not shown).
|
An improved grout impregnation method which uses an injection tube for contacting and mixing different kinds of materials supplied thereinto separately to prepare a grout and impregnates the grout into the earth through an injecting opening provided at a tip end of the tube.
In this method, a first pressure-holding valve is provided within a higher-pressure path for one of the materials which is supplied under a higher pressure, a mixing section is provided downstream the first pressure-holding valve but in the vicinity thereof for contacting and mixing said one of the materials with another one which is supplied under a lower pressure, and a second pressure-holding valve is provided downstream the mixing section; said one of the materials is passed through the first pressure-holding valve, which reduces the pressure of said one of the materials, and then contacted and mixed with said another one at the mixing section; the contacting and mixing is carried out under a pressure exceeding an atmospheric pressure and determined by the second pressure-holding valve; and the grout resulting from the contacting and mixing and passing through the second pressure-holding valve is impregnated into the earth through the injection opening.
| 4
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a pseudo GPS signal transmitting system in a base station which is installed on the ground and transmits a pseudo GPS signal for use as one of GPS satellites.
2. Description of the Related Art
To use a conventional base station as one of GPS satellites in determining the position, the time system of the base station is controlled according to the GPS time. Specifically, just as each GPS satellite transmits a distance-measuring signal in synchronization with the GPS time, the base station also transmits a distance-measuring signal (a pseudo GPS signal) of a specified reference point in synchronization with the GPS time.
However, since the Department of Defense has been implementing a selective availability (SA) policy, whereby the accuracy of GPS time is forced to deteriorate, it is very difficult to accurately monitor the GPS time serving as a reference in a base station.
Such monitoring errors in the GPS time in a base station affect the accuracy of measuring distance between the base station and the user's GPS receiver, consequently degrading the position-determining accuracy of the user's GPS receiver.
SUMMARY OF THE INVENTION
As described above, since the pseudo GPS signal transmitting system in a conventional base station cannot monitor the GPS time accurately owing to SA, the monitoring errors affect the accuracy of measuring the distance between the base station and the user's GPS receiver, consequently degrading the position-determining accuracy of the user's GPS receiver.
The object of the present invention is to provide a pseudo GPS transmitting system in a base station which prevents GPS-time monitoring errors due to SA from affecting the accuracy of distance measurement between the base station and the user's GPS receiver, thereby maintaining the position-determining accuracy of the user's GPS receiver.
The foregoing object is accomplished by providing a pseudo GPS signal transmitting system in a base station installed on the ground and transmitting a pseudo GPS signal for use as one of GPS satellites, comprising: a GPS receiving antenna for picking up radio waves from GPS satellites; a monitor GPS receiver containing a receiving section for receiving GPS signals from each GPS satellite via the GPS receiving antenna, a satellite data sensing section for sensing satellite data from the received GPS signals, a pulse generating section for generating user clock pulses synchronized with a reference clock, and an observation data calculating section for obtaining observation data from the received GPS signals on the basis of the user clock pulses; a data processing unit containing an error data computing section for determining a pseudo range error value for the theoretical distance between a transmitting GPS satellite and a known receiving point from the satellite data and the observation data obtained at the monitor GPS receiver, and a transmission data generating section for formatting these data items in a specified manner to generate transmission data; a transmitter containing a PN code generating section for generating PN codes for spectrum diffusion in synchronization with the user clock pulses, a pseudo GPS signal generating section for generating pseudo GPS signals by combining PN codes generated at the PN code generating section with the transmission data from the data processing unit on the basis of the user clock pulses, a carrier generating section for generating a carrier signal synchronized with the reference clock, a modulator for modulating the carrier signal generated at the carrier generating section using the pseudo GPS signal, and a power amplifier for power-amplifying the output of the modulator; and a transmitting antenna for transmitting the pseudo GPS signal from the transmitter in a given direction, wherein the pseudo GPS signal sent from the transmitting antenna is transmitted directly or via a specific stationary satellite to a user GPS receiver.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention.
FIG. 1 is a block circuit diagram of a first embodiment of a pseudo GPS signal transmitting system in a base station according to the present invention;
FIG. 2 showing a basic concept of overlay in the first embodiment;
FIG. 3 is a block circuit diagram of a second embodiment of a pseudo GPS signal transmitting system in a base station according to the present invention; and
FIG. 4 shows a basic concept of the entire system in a case where there are two pseudolite terrestrial stations as base stations in the second embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, referring to the accompanying drawings, embodiments of the present invention will be explained.
FIG. 1 shows the configuration of a first embodiment of a pseudo GPS signal transmission system according to the present invention.
A monitor GPS receiver A1 comprises a receiving section 11 for receiving the GPS signal from each GPS satellite via a GPS receiving antenna A2, a satellite data sensing section 12 for sensing satellite data (ephemeris and almanac) from the received GPS signals, a pulse generating section 13 for generating user clock pulses synchronized with the reference clock from a reference oscillator A3, and an observation data calculating section 14 for obtaining the observation data (including a pseudo range, and a delta range) from the received GPS signals in accordance with the user clock pulses.
A data processing unit A4 comprises an error data computing section 41 for determining the pseudo range error value for the theoretical distance between the transmitting GPS satellite and the receiving point (known) from the satellite data and observation data obtained from the monitor GPS receiver A1, and a transmission data generating section 43 for producing transmission data by formatting these data items in a specified manner.
A transmitter A5 comprises a PN code generating section 51 for spectrum diffusion, a pseudo GPS signal generating section 52 for producing a pseudo GPS signal by combining the PN codes generated at the PN code generating section with the transmission data from the data processing unit A4, a carrier generating section 53 for producing a carrier signal synchronized with the reference clock from the reference oscillator A3, a modulator 54 for modulating the generated carrier signal using the pseudo GPS signal, and a power amplifier 55 for power-amplifying the output of the modulator 54.
A GPS transmitting antenna A6 is directed toward a specific stationary satellite and transmits the pseudo GPS signal from the transmitter A5 to a user GPS receiver via the stationary satellite.
That is, with the above configuration, the entire processing is effected in synchronization with the user clock pulses. Hereinafter, such processing is called a user clock synchronizing method.
Since the format of the transmission data is written in various technical books and documents, its detailed explanation will be omitted. The method is characterized in that the amount of delay in the pseudo GPS signal over the entire hardware is added as overlay channel correlation data items.
Hereinafter, using overlay as an example, explanation will be given as to how the user GPS receiver determines the position by the user clock synchronizing method, regardless of time errors due to SA.
FIG. 2 shows a basic concept of overlay. In the figure, reference symbol A indicates the base station of FIG. 1, B a GPS satellite, C a stationary satellite equipped with a transponder that receives radio waves from the base station A and reradiates them toward a specific range, D a navigating object (user) now moving in the specific range, D1 a user GPS receiver, and D2 a user GPS antenna. Here, the parameters in FIG. 2 are defined as follows:
ρ m : the pseudo range between GPS satellite B and GPS receiving antenna A2
γ m : the actual distance between GPS satellite B and GPS receiving antenna A2
ρ u : the pseudo range between GPS satellite B and user GPS antenna D2
γ u : the actual distance between GPS satellite B and user GPS antenna D2
ρ o : the pseudo range between GPS transmitting antenna A6 and user GPS antenna D2
γ o : the actual distance between GPS transmitting antenna A6 and user GPS antenna D2
The relationship between each pseudo range and the corresponding actual distance is as follows:
ρ.sub.m =γ.sub.m -Δρ.sub.mc +Δρ.sub.all +Δρ.sub.sa(t1) +Δρ.sub.mh (1)
ρ.sub.u =γ.sub.u -Δρ.sub.uc +Δρ.sub.all +Δρ.sub.sa(t2) +Δρ.sub.uh (2)
ρ.sub.o =γ.sub.o -Δρ.sub.uc +Δρ.sub.tc +Δρ.sub.th +Δρ.sub.tr +Δρ.sub.uh(3)
where
Δρ mc : a range error due to a clock error (delay) in monitor GPS receiver A1
Δρ uc : a range error due to a clock error (delay) in user GPS receiver D1
Δρ tc : a range error due to a clock error (delay) in transmitter A5
Δρ all : a range error (excluding an SA error) in GPS satellite due to all error factors including the ionosphere
Δρ sa (ti): a range error due to an SA error at time ti (i=1, 2, . . . )
Δρ mh : a hardware delay in monitor GPS receiver A1 (from monitor GPS receiving antenna A2 to a spectrum reverse diffusion)
Δρ uh : a hardware delay in user GPS receiver D1 (from user GPS antenna D2 to a spectrum reverse diffusion)
Δρ th : a hardware delay in transmitter A5 (from a spectrum diffusion to transmitting antenna A6)
Δρ tr : a hardware delay in the transponder of stationary satellite C
Here, ionospheric errors in overlay up-link and down-link radio waves are not included in equation (3), assuming that it is possible to remove them by modeling.
From equation (1), the correction value Apcor for each satellite is expressed as follows:
Δρ.sub.cor =-Δρ.sub.mc +Δρ.sub.sa(t1) +Δρ.sub.mh (4)
Because the user GPS receiver D1 corrects the pseudo range of each of the observed GPS satellites B, from equation (2) and equation (4), the pseudo range ρ u ' after correction is expressed as follows:
ρ.sub.u '=γ.sub.u -(Δρ.sub.uc -Δρ.sub.mc)+(Δρ.sub.sa(t2) -Δρ.sub.sa(t1))+(Δρ.sub.uh -Δρ.sub.mh)(5)
Here, since the difference between reception time t 1 at the base station and reception time t 2 at user GPS receiver D1 is short for the same GPS signal, Δρ sa (t2.sub.) can be considered to be almost equal to ρ sa (t1). At this time, ρ u ' is expressed as follows:
ρ.sub.u '=γ.sub.u -(Δρ.sub.uc -Δρ.sub.mc)+(Δρ.sub.uh -Δρ.sub.mh)(6)
Now, an overlay signal will be considered. Since Δρ tc synchronizes with Δρ mc in this method, these fulfill the following relationship:
Δρ.sub.mc =Δρ.sub.tc (7)
More precisely, γ o is broken down as follows:
γ.sub.o =γ.sub.ou +γ.sub.od (8)
where γ ou : the actual distance between transmitting antenna A6 and stationary satellite C
γ od : the actual distance between stationary satellite C and user GPS antenna D2
Substituting equation (7) and equation (8) into equation (3) gives the following equation:
ρ.sub.o =γ.sub.ou +γ.sub.od -Δρ.sub.uc +Δρ.sub.mc +Δρ.sub.th +Δρ.sub.tr +Δρ.sub.uh (9)
Here, after (γ ou +Δρ th +Δρ tr +Δρ mh ) is transmitted as overlay channel correction data, from equation (9), the pseudo range ρ o ' after correction at user GPS receiver D1 is expressed as follows:
ρ.sub.o '=γ.sub.od -(Δρ.sub.uc -Δρ.sub.mc)+(Δρ.sub.uh -Δρ.sub.mh)(10)
Because equation (6) and equation (10) have the same error of-(Δρ uc -Δρ mc )+(Δρ uh -Δρ mh ), it is possible to determine a position using the pseudo GPS signal without being affected by SA.
Therefore, when making DGPS corrections and measuring a distance using the pseudo GPS signal, the pseudo GPS signal transmitting system employing the user clock synchronizing method can avoid time errors due to SA, thereby maintaining the position-determining accuracy of the user GPS receiver.
While in the embodiment, the operation has been explained, using overlay as an example, the method may be applied to a pseudolite approach in which a pseudo GPS signal is transmitted directly to a user GPS receiver, not by way of a stationary satellite.
FIG. 3 shows the configuration of a second embodiment of a pseudo GPS signal transmitting system according to the present invention. In FIG. 3, the same parts as those in FIG. 1 are indicated by the same reference symbols.
A monitor GPS receiver A1 comprises a receiving section 11 for receiving GPS signals from a plurality of GPS satellites and a pseudo GPS signal from another base station via a GPS receiving antenna A2, a satellite/base station data sensing section 12 for sensing satellite data (ephemeris and almanac) from the received GPS signals and the base station data (including the position of the base station) from the pseudo GPS signal, a pulse generating section 13 for generating user clock pulses synchronized with the reference clock from a reference oscillator A3, and an observation data calculating section 14 for obtaining the observation data (including a pseudo range, and a delta range) from the received GPS signal and pseudo GPS signal in accordance with the user clock pulses.
A data processing unit A4 comprises an error data computing section 41 for determining the pseudo range error value for the theoretical distance between the transmitting GPS satellite and the receiving point (known) and the pseudo range error value for the theoretical distance between another transmitting base station and the receiving point (known) from the satellite/base station data and observation data obtained from the monitor GPS receiver A1, and a transmission data generating section 43 for producing transmission data by formatting these data items in a specified manner.
A transmitter A5 comprises a PN code generating section 51 for spectrum diffusion, a pseudo GPS signal generating section 52 for producing pseudo GPS signals by combining PN codes generated at the PN code generating section with the transmission data from the data processing unit A4, a carrier generating section 53 for producing a carrier signal synchronized with the reference clock from the reference oscillator A3, a modulator 54 for modulating the generated carrier signal using the pseudo GPS signal, and a power amplifier 55 for power-amplifying the output of the modulator 54.
A GPS transmitting antenna A6 transmits the pseudo GPS signal from the transmitter A5 to a user GPS receiver and another base station.
That is, with the above configuration, a pseudo GPS signal is generated by, on the basis of the pseudo GPS signal transmitted from the different station, making DGPS corrections and measuring a distance, taking into account time errors between this station and a different station.
Since the format of the transmission data has been written in various technical books and documents, its detailed explanation will be omitted. The method is characterized in that the amount of delay in the pseudo GPS signal over the entire hardware is added as one of the data items.
Hereinafter, using a case where two pseudolite terrestrial stations as base stations, explanation will be given as to how a user GPS receiver measures the position, regardless of time errors due to SA.
FIG. 4 shows a basic concept of the entire system. In the figure, reference symbols A and B indicate pseudolite terrestrial stations, C a GPS satellite, D a navigating object (user) now moving in a range where it can receive the respective pseudo GPS signals from the terrestrial stations A and B and the GPS signal from a GPS satellite C, D1 a user GPS receiver, and D2 a user GPS antenna. Here, the parameters in FIG. 4 are defined as follows:
ρ m1 : the pseudo range between GPS satellite C and GPS receiving antenna A2 at terrestrial station A
γ m1 : the actual distance between GPS satellite C and GPS receiving antenna A2 at terrestrial station A
ρ m2 : the pseudo range between GPS satellite C and GPS receiving antenna B2 at terrestrial station B
γ m2 : the actual distance between GPS satellite C and GPS receiving antenna B2 at terrestrial station B
ρ u : the pseudo range between GPS satellite C and user GPS antenna D2
γ u : the actual distance between GPS satellite C and user GPS antenna D2
ρ s1 : the pseudo range between GPS transmitting antenna B6 at terrestrial station B and GPS receiving antenna A2 at terrestrial station A
γ s1 : the actual distance between GPS transmitting antenna B6 at terrestrial station B and GPS receiving antenna A2 at terrestrial station B
ρ s2 : the pseudo range between GPS transmitting antenna A6 at terrestrial station A and GPS receiving antenna B2 at terrestrial station B
γ s2 : the actual distance between GPS transmitting antenna A6 at terrestrial station A and GPS receiving antenna B2 at terrestrial station B
ρ t1 : the pseudo range between GPS transmitting antenna A6 at terrestrial station A and user GPS antenna D2
γ t1 : the actual distance between GPS transmitting antenna A6 at terrestrial station A and user GPS antenna D2
ρ t2 : the pseudo range between GPS transmitting antenna B6 at terrestrial station B and user GPS antenna D2
γ t2 : the actual distance between GPS transmitting antenna B6 at terrestrial station B and user GPS antenna D2
The relationship between each pseudo range and the corresponding actual distance is as follows:
ρ.sub.m1 =γ.sub.m1 -Δρ.sub.mc1 +Δρ.sub.all +Δρ.sub.sa (11)
ρ.sub.m2 =γ.sub.m2 -Δρ.sub.mc1 +Δρ.sub.all +Δρ.sub.sa (12)
ρ.sub.u =γ.sub.u -Δρ.sub.uc +Δρ.sub.all +Δρ.sub.sa (13)
ρ.sub.s1 =γ.sub.s1 -Δρ.sub.mc1 +Δρ.sub.tc2(14)
ρ.sub.s2 =γ.sub.s2 -Δρ.sub.mc1 +Δρ.sub.tcl(15)
ρ.sub.t1 =γ.sub.t1 -Δρ.sub.uc +Δρ.sub.tc1(16)
ρ.sub.t2 =γ.sub.t2 -Δρ.sub.uc +Δρ.sub.tc2(17)
where
Δρ mc1 : a range error due to a clock error (delay) in monitor GPS receiver A1 at terrestrial station A
Δρ mc2 : a range error due to a clock error (delay) in monitor GPS receiver B1 at terrestrial station B
Δρ uc : a range error due to a clock error (delay) in user GPS receiver D1
Δρ tc1 : a range error due to a clock error (delay) in transmitter A5 at terrestrial station A
Δρ tc2 : a range error due to a clock error (delay) in transmitter B5 at terrestrial station B
Δρ all : a range error (excluding an SA error) in GPS satellite C due to all error factors including the ionosphere
Δρ sa : a range error due to an SA error
From equation (11), the correction value Δρ cor1 for GPS satellite C is expressed as follows:
Δρ.sub.cor1 =-Δρ.sub.mc1 +Δρ.sub.all +Δρ.sub.sa (18)
Because the user GPS receiver D1 corrects the pseudo range of each of the observed GPS satellites C, from equation (13) and equation (18), the pseudo range ρ u ' after correction is expressed as follows:
ρ.sub.ul '=γ.sub.u -Δρ.sub.uc +Δρ.sub.mc1(19)
Now, a pseudolite signal will be considered. When the transmission signal from the pseudolite terrestrial station B is monitored at the pseudolite terrestrial station A, the correction value Δρ cor2 can be determined by the following equation at pseudolite terrestrial station:
Δρ.sub.cor2 =-ρ.sub.mc1 +Δρ.sub.tc2(20)
On the other hand, the user GPS receiver D1 receives correction value Δρ cor2 of pseudolite terrestrial station B carried on the data from pseudolite station A, and then corrects the pseudo range of the pseudolite terrestrial station B observed with user GPS receiver D. The pseudo range ρ t2 ' after correction can be determined from the following equation derived from equation (17) and equation (20):
ρ.sub.t2 '=γ.sub.t2 -ΔΔρ.sub.uc +Δρ.sub.mc1 (21)
The case where monitoring is effected at pseudolite terrestrial station A has been explained. Similarly, a case where monitoring is effected at pseudolite terrestrial station B will be considered. The pseudo range ρ u2 ' after correction for each GPS satellite is expressed as follows:
ρ.sub.u2 '=γ.sub.u -Δρ.sub.uc +Δρ.sub.mc2(22)
The pseudo range ρ t1 ' after correction in the pseudolite terrestrial station A is expressed as follows:
ρ.sub.t1 '=γ.sub.t1 -ρ.sub.uc +Δρ.sub.mc2(23)
With the user GPS receiver D1, when use of pseudolite terrestrial station B achieves DOP (Dilution of Precision) optimum, a position can be determined from equation (19) and equation (21) (because these equations have the same expression: a common error-Δρ uc +Δρ mc1 ). Similarly, when use of pseudolite terrestrial station A achieves DOP optimum, a position can be determined from equation (22) and equation (23).
Furthermore, a case where DOP optimum is achieved when both pseudolite stations A and B are used will be considered. By substituting the values for the same GPS satellite C into equation (19) and equation (22) to obtain the difference between them, the difference between Δρ mc1 and Δρ mc2 can be determined as follows:
Δρ.sub.mc1 -Δρ.sub.mc2 =ρ.sub.u1 '-ρ.sub.u2(24)
Therefore, a position can be determined by using equation (19), equation (21), equation (23) and equation (24), or by using equation (21), equation (22), equation (23), and equation (24).
Accordingly, with the base-station's pseudo GPS signal transmitting system constructed as described above, a pseudo GPS signal is generated by, on the basis of the pseudo GPS signal from another base station, making DGPS corrections and measuring a distance, taking into account time errors between the base stations. This enables the user to avoid time errors due to SA, thereby maintaining the position-determining accuracy of the user GPS receiver.
While in the embodiment, two pseudolite terrestrial stations are used, a position can be determined even when three or more pseudo terrestrial stations are used. The present invention is not limited to the pseudolite technique, but may be applied to range overlay.
The present invention may be practiced or embodied in still other ways without departing from the spirit or essential character thereof.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
|
The object of this invention is to prevent GPS time monitor errors from effecting the distance-measuring accuracy. To achieve the object, a monitor GPS receiver receives GPS signals from each GPS satellite via a receiving antenna, senses satellite data, and obtains observation data on the basis of user clock pulses synchronized with a reference clock from a reference oscillator. A data processing unit computes a pseudo range error value from the satellite data and observation data obtained at the monitor GPS receiver on the basis of the user clock pulses, and formats these data items to generate transmission data. A transmitter combines PN codes with the transmission data on the basis of the user clock pulses to generate a pseudo GPS signal, modulates a carrier signal synchronized with the reference clock, and power-amplifies the modulated output. A transmitting antenna is directed toward a specific stationary satellite and transmits a pseudo GPS signal to a user GPS receiver via the stationary satellite.
| 6
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. 119 based upon Japanese Patent Application Serial No. 2005-001033, filed on Jan. 5, 2005. The entire disclosure of the aforesaid application is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a cancer-specific gene and a diagnostic kit using the same, and further relates to a method for using the diagnostic kit.
BACKGROUND OF THE INVENTION
The most crucial challenge in measures against cancer is the early detection of cancer. Particularly, early detection is important for cancers originating from the upper part of the large intestine since they cause only limited subjective symptoms and the medical condition may likely to be in its advanced stage by the time of discovery.
Traditional measures against large intestine cancer include screening by the fecal occult blood test, diagnosis by serum markers such as CEA or CA19-9, and diagnosis during a course of treatment. However, the positive rates of these methods are high only for advanced cancers and extremely low for early cancers, making accurate diagnosis difficult in their early stages.
Meanwhile, a biological diagnostic method using a cancer tissue-specific protein marker is suggested as a method allowing simple and reliable early diagnosis of malignancy. This method can be performed on a broad range of asymptomatic subjects since it does not require a large-scale facility and causes small burdens for the subject. For instance, Japanese Patent Application Publication No. H07-51065 discloses a usage of glycoprotein 39 as a tumor marker.
In addition, International Patent Application Publication No. WO/2004/018679 describes a technology regarding a cancer diagnostic kit using CENP-A. Sugata, N., et al., “Human CENP-H multimers colocalize with CENP-A and CENP-C at active centromere-kinetochore complexes,” Hum. Mol. Genet ., vol. 9, no. 19, 2000, pp. 2919-2926 discloses the sequences of human CENP-H protein and its corresponding encoding nucleotide which correspond to SEQ ID No: 1 and SEQ ID No: 2 of the present application. Sugata et al. also discloses the biochemical characterization and the localization of CENP-H protein suggesting its role in cell cycle progression.
WO 03/104426 discloses CENP-E with additional background information relating to CENP-A, B, C, and D. Also, WO 03/104426 discloses a method to detect the abnormal amount of CENP-E protein in biopsied tissue for diagnosis of predisposition or actual clinical symptoms of cancer and the kits for detecting the presence of aberrant CENP-E protein expression.
However, cancer expression cannot be thoroughly verified by the technology described in the above JP-A-H7-51065 alone and a plurality of means must be used to ensure positive identifications.
Considering the above situation, the purpose of the present invention is to provide a further identification of a gene related to cancer expression and a diagnostic kit using the same.
SUMMARY OF THE INVENTION
Considering the above situation, the present invention employs specific means described below.
A first means is a polynucleotide as in one of the following (a)-(c):
(a) a polynucleotide consisting of a base sequence as in SEQ ID NO: 1 or a complementary base sequence thereof; (b) a polynucleotide consisting of a base sequence having at least 70% homology with the base sequence as in SEQ ID NO: 1 or the complementary base sequence thereof; and (c) a polynucleotide coding a protein consisting of an amino-acid sequence as in SEQ ID NO: 2, or another amino-acid sequence defined by the amino-acid sequence having one or several amino acid deletions, substitutions or additions, wherein the polynucleotide is a marker for detecting cancer.
The polynucleotide in this means may greatly contribute to a cancer diagnosis when used as a marker since the polynucleotide has been discovered to exhibit a high expression in cancer tissues. The homology with the base sequence as in SEQ ID NO: 1 is preferably equal to or greater than 70%, more preferably equal to or greater than 80%, and even more preferably equal to or greater than 90%.
A second means is a cancer diagnostic kit comprising a primer consisting of a base sequence as in SEQ ID NO: 3.
A third means is a cancer diagnostic kit comprising a primer consisting of a base sequence as in SEQ ID NO: 4.
A fourth means is a cancer diagnostic kit comprising a primer set consisting of the primers as in SEQ ID NOS: 3 and 4. Each of these cancer diagnostic kits may be used to diagnose rectal cancer or colon cancer.
A fifth means is a method comprising the steps of: measuring an expression level of a protein consisting of an amino-acid sequence as in SEQ ID NO: 2 for each of two collected cells; and determining whether or not the ratio between the measured expression levels is equal to or great than 1.7. In this case, one of the two samples is collected from a non-cancer tissue; the other sample is collected from, for example, a tissue suspected to be a cancer tissue; and if the expression level ratios of the two samples are different, the subject from whom the samples were collected may be determined to be at a high risk of cancer.
Preferably for this means, the step of measuring the expression level of the protein is performed with the western blot, wherein one of the two collected cells is a cell in a non-cancer tissue, wherein one of the two collected cells is a cell in a cancer tissue.
As described above, a gene related to cancer expression may be newly identified, and a diagnostic kit using the same may be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing western blot results for CENP-H;
FIG. 2 is a diagram showing western blot results for hMis12;
FIG. 3 is a diagram showing the results of staining cross-sectional areas of rectal cancer tissues and their respective nearby non-rectal cancer tissues with anti-human CENP-H polyclonal antibody;
FIG. 4 is a diagram showing analysis results on amounts of CENP-H mRNA in each of the surfaces of rectal cancer tissues and normal tissues using RT-PCR and real-time quantitative PCR; and
FIG. 5 is a diagram showing analysis results on amounts of CENP-H mRNA in each of the surfaces of rectal cancer tissues and normal tissues using RT-PCR and real-time quantitative PCR.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
One embodiment of the present invention will be described below.
Tissue Collection
Body tissues were collected with a surgical method from 15 patients with early-stage colorectal cancer. The tissues were taken from cancer tissue (hereinafter referred to as “cancer tissue”) and tissue at a part 5-10 cm away from the cancer tissue (hereinafter referred to as “non-cancer tissue”), respectively. The collected tissues were immersed in liquid nitrogen and stored at −80° C.
Protein Extraction
The cryonically-preserved tissues were then placed into lysis buffer (7 M urea, 2 M thiourea, 2% 3-[(3-Cholamidopropyl)Dimethylammonio]-1-Propanesulfonate, 0.1 M DTT, 2% IPG buffer (made by Amersham Pharmacia Biotech), 40 mM Tris), lysed using polytron homogenizer (made by Kinematica), and centrifuged at 10,000 g and 4° C. for 1 hour to collect supernatant and extract proteins.
Immunoblot
The proteins were blotted to polyvinylidene fluoride membranes (made by Millipore) in a tank transfer device (made by Bio-Rad) and the membranes were then blocked with phosphate buffered saline (PBS) containing 5% skim milk. Next, 1:5000 diluted rabbit anti-CENP-H antibody, 1:100 diluted rabbit anti-hMis12 antibody and 1:500 diluted goat anti-β-actin antibody, each placed in the blocking buffer, were used as a primary antibody; and 1:3000 diluted goat anti-rabbit IgG HRP and 1:500 diluted rabbit anti-goat IgG HRP, each placed in the blocking buffer, were used as a secondary antibody.
Note that antibodies on the antigen membrane were detected with enhanced chemiluminescence detection reagent (made by Amersham Pharmacia Biotech). Also the intensity of each band was measured with an NIH image.
PCR and Real-Time Quantitative PCR
TotalRNA was extracted from the cancer tissue and the non-cancer tissue, respectively, using RNeasy Mini Kit (made by Qiagen). Also cDNA was synthesized from each extracted totalRNA, respectively, using a 1st Strand cDNA Synthesis Kit for RT-PCR (made by Roche).
Then each cDNA obtained by this synthesis was used as a template to amplify the cDNA of CEMP-H with PCR. In the PCR, a primer comprising a base sequence as in SEQ ID NO: 3 or 4 were used as the forward and reverse primer, respectively, and cDNA of GAPDH or β-actin were amplified as the controls.
Subsequently cDNA real-time quantitative PCR for CENP-H was performed in a LIGHTCYCLER®capillary. For the PCR reaction mixture, 3.0 mM of MgCl 2 , 0.5 μM of the primer as in SEQ ID NO: 3 and 0.5 μM of the primer as in SEQ ID NO: 4 were added to LIGHTCYCLER® DNA Master SYBR Green I (FastStart Taq DNA polymerase, dNTP, buffer, SYBR Green I), and the procedure was conducted within a total of 2.0 μl.
LIGHTCYCLER® software version 3.3 (made by Roche) was then used for analysis.
Immunohistochemical Staining Method
The frozen tissue sections were dried on a glass slide and fixed in 4° C. acetone. The tissues were then washed with PBS 3 times and blocked with the blocking buffer (10% fetal bovine serum/PBS) for 1 hour.
The sample was incubated for 1 hour in 3% bovine serum albumin/PBS using one or both of 1:2000 diluted rabbit anti-CENP-H antibody and 1:1000 diluted anti-human CENP-A monoclonal antibody. After washing with PBS, the sample was incubated for 1 hour with 1:1000 diluted ALEXA FLUOR® 488- or 594-bound goat anti-rabbit anti-mouse IgG secondary antibody (made by Molecular Probes) and/or ALEXA FLUOR® 594-bound goat anti-mouse IgG secondary antibody.
DNAs were counterstained using DAPI III Counterstain (made by Vysis). The sample was observed with a fluorescence microscope (made by Leica QFISH). The tissue sections were stained with hematoxylin for 30 minutes for HE staining, dried over 100% ethanol and xylene and encapsulated with Permount.
Results
FIG. 1 shows results of the western blot. As shown in FIG. 1 , CENP-H was highly expressed in the cancer tissue in any of the 15 cases. Particularly, a ratio between the non-cancer tissue and the cancer tissue CENP-H expressions was 1.7-9.6, indicating a large difference between these two kinds of tissues. For another centromere protein hMis12, on the other hand, no notable difference was discovered between the cancer tissue and the non-cancer tissue. (See FIG. 2 , in which tissues with the same case number as in FIG. 1 are identical with those in FIG. 1 ).
Next, in order to verify that CENP-H is expressed in the cancer cell, but not in stromal cells, cross-sectional areas of colorectal cancer tissues and nearby non-cancer tissues were stained with an anti-human CENP-H polyclonal antibody. The results are shown in FIG. 3 . Note that FIG. 3( a ) shows an HE-stained image of the cancer tissue; FIGS. 3( b ), ( c ) and ( d ) show a CENP-H antibody immunostained image of the cancer tissue; FIG. 3( e ) shows an HE-stained image of the non-cancer tissue; and FIG. 3( f ) shows a CENP-H-stained image of the non-cancer tissue.
As a result, it was confirmed that CENP-H existed as small patchy points in cell nuclei at positions coinciding with the centromeres in a similar manner to that of other centromere proteins such as CENP-A and CENP-C. It was also confirmed that the CENP-H had been increased both in number and size in the cancer tissues ( FIGS. 3( c ) and ( d )) compared to the non-cancer tissue ( FIG. 3( f )). It should be noted that the stained CENP-H was verified not in the stromal cells, but in the cancer tissue epithelia. Also the present experiment was conducted on. various tissue sections and all the results were similar to each other.
Accordingly, it was confirmed that CENP-H was expressed in cancer cells.
Subsequently, in order to verify that the CENP-H overexpression was a result of its increase due to transcription, amounts of mRNA of CENP-H in the colorectal cancer tissues and the non-cancer tissues were analyzed, respectively, using RT-PCR and real-time quantitative PCR. The results are shown in FIGS. 4 and 5 .
As shown in FIG. 4 , an expression level of the CENP-H mRNA in the cancer tissues is far more increased than in the non-cancer tissues. Furthermore, it was discovered that the expression level of the CENP-H mRNA indicated a strong correlation with the CENP-H expression ratio between the non-cancer tissues and the cancer tissues illustrated in FIG. 1 . As a control, when confirmation was done pertaining to GAPDH, there was no significant difference in the expression level of the CENP-H mRNA between the cancer tissues and the non-cancer tissues.
FIG. 5 illustrates a comparison of the mRNA expression levels shown in FIG. 4 between the non-cancer tissues and the cancer tissues using StatView statistical analysis software. According to FIG. 5 , the CENP-H mRNA expression level in the cancer tissues (Cancer) was 5 times higher than that of the non-cancer tissues (Normal). In this way, the presence of cancer can be also verified by examining the CENP-H expression level.
INDUSTRIAL AVAILABILITY
Thus according to the present invention, a gene related to cancer expression may be newly identified, and a diagnostic kit using the same may be also provided.
|
The present invention provides a new additional identification of a gene related to cancer expression and a diagnostic kit using the same.
| 2
|
REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of pending International Patent Application PCT/KR2013/008989 filed on Oct. 8, 2013, which designates the United States and claims priority of Korean Patent Application No. 10-2012-0124160 filed on Nov. 5, 2012, the entire contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a heating apparatus or a hot air blowing apparatus and, more particularly, to a germicidal heating apparatus using superheated vapor in which air is sterilized while passing through a space of a sheath heater having the temperature of 600° C. or more and then is mixed with high temperature dry and pure vapor discharged from a cylindrical water vessel that is installed to cool the sheath heater, thereby producing aseptic greenhouse air good for organisms and causing an increase in indoor temperature owing to the vapor of high energy.
BACKGROUND OF THE INVENTION
[0003] In general, for example, a hot air fan heater or an oil fan heater is universally used as a conventional heating apparatus. The hot air fan heater includes a heater to heat air, a fan to blow the air heated in the heater, and a cabinet body configured to receive the heater and the fan therein. The hot air fan heater is adapted to heat an indoor space by heating air inside the cabinet body using the heater and, thereafter, exhausting the heated air from the cabinet body using the fan.
[0004] In addition, the oil fan heater includes a tank in which oil is stored, a burner to burn the oil supplied from the tank, a fan to blow air heated by the burner, and a cabinet body configured to receive the tank, the burner and the fan therein. The oil fan heater is adapted to heat an indoor space by exhausting the air heated by the burner from the cabinet body using the fan.
[0005] However, in the case of the conventional hot air fan heater, air is heated by the heater and additionally dried prior to being exhausted to an indoor space, which causes generation of dry indoor air. Moreover, the resulting dry hot air has a low thermal capacity and results in a poor heating efficiency. In addition, in the case of the oil fan heater, indoor ventilation is required since carbon dioxide is generated during burning of oil and, due to environmental load applied by carbon dioxide, there is a demand for a heating apparatus that causes substantially low environmental load in consideration of global warming.
SUMMARY OF THE INVENTION
[0006] Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a heating apparatus or a hot air blowing apparatus and, more particularly, a germicidal heating apparatus using superheated vapor in which air is sterilized while passing through a space of a sheath heater having the temperature of 600° C. or more and then is mixed with high temperature dry and pure vapor discharged from a cylindrical water vessel that is installed to cool the sheath heater, thereby producing aseptic greenhouse air good for organisms and causing an increase in indoor temperature owing to the vapor of high energy.
[0007] In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of a germicidal heating apparatus using superheated vapor, the apparatus including a water supply unit configured to supply water, a superheated vapor generation unit configured to generate superheated vapor using the water supplied from the water supply unit, and a blower configured to blow the superheated vapor generated in the superheated vapor generation unit through a discharge opening, the apparatus including an annular vessel constituting the superheated vapor generation unit, the annular vessel being configured to receive the water supplied from the water supply unit and provided at the entire inner peripheral surface thereof with a spiral sheath heater, and the annular vessel including an inner sidewall and an outer sidewall configured in such a manner that an upper end of the inner sidewall is bent so as to come into close contact with the outer sidewall in order to prevent leakage of the received water and to ensure discharge of vapor generated by heat of the sheath heater, a semi-opening type cover provided at an upper end of the annular vessel, the semi-opening type cover serving to secondarily prevent leakage of the water received in the annular vessel, an auxiliary fan and an auxiliary heater arranged in a vapor transfer path between the annular vessel and the discharge opening, the auxiliary fan and the auxiliary heater serving to control a temperature around the discharge opening so as to fall within a range of 100° C. to 150° C., a noise reduction device located in the vapor transfer path between the annular vessel and the discharge opening in order to reduce noise having a negative effect on organisms in consideration of an air flow rate and air pressure of the blower, the noise reduction device having a V-shaped or I-shaped cross section to maximize a sound absorption area, and a plurality of ceramic members arranged at the exterior of the annular vessel to achieve minimized heat loss and maximized usage of vapor and to prevent superheating inside the apparatus.
[0008] With a heating apparatus or a hot air blowing apparatus as proposed in an embodiment, as air is sterilized while passing through a space of a sheath heater having the temperature of 600° C. or more and then is mixed with high temperature dry and pure vapor discharged from a cylindrical water vessel that is installed to cool the sheath heater, there are effects of producing aseptic greenhouse air good for organisms and causing an increase in indoor temperature owing to the vapor of high energy.
[0009] In addition, the resulting high temperature dry vapor, i.e. superheated vapor tends to emit far infrared heat and anions. Far infrared heat is good for growth and anions have sterilization and deodorization functions as known. In addition, when an indoor temperature is set to about 22 degrees, the superheated vapor may maintain an indoor humidity at about 45%, which efficiently prevents respiratory diseases, xeroderma, fatigue and stress, thus having an advantageous effect on organisms.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is an exemplary sectional view illustrating a configuration of a germicidal heating apparatus using superheated vapor according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0011] Hereinafter, a germicidal heating apparatus using superheated vapor according to the present invention will be described in detail with reference to the annexed drawing.
[0012] The annexed FIG. 1 is an exemplary sectional view illustrating a configuration of a germicidal heating apparatus using superheated vapor according to the present invention. The germicidal heating apparatus using superheated vapor according to the present invention, designated by reference numeral 100 , includes a water supply unit 110 to supply water, a superheated vapor generation unit 120 to generate superheated vapor using the water supplied from the water supply unit 110 , and a blower 130 to blow the superheated air generated in the superheated vapor generation unit 120 through a discharge opening.
[0013] At this time, the superheated vapor generation unit 120 includes an annular vessel 121 to receive the water from the water supply unit 110 and a spiral sheath heater 122 formed at the entire inner peripheral surface of the annular vessel 121 . To prevent leakage of the water received in the annular vessel 121 and to ensure discharge of the vapor generated by heat of the sheath heater 122 , an upper end of an inner sidewall 121 B of the annular vessel has a bent or protruding portion so as to come into close contact with an outer sidewall 121 A.
[0014] Accordingly, the upper end of the inner sidewall 121 B and the outer sidewall 121 A of the annular vessel define a nozzle for discharge of the vapor.
[0015] In the configuration as described above, note that reference numeral 121 is a common reference numeral designating reference numerals 121 A to 121 C of FIG. 1 and is not actually written in the drawing.
[0016] In addition to the above-described configuration, the germicidal heating apparatus further includes a cabinet body 140 to receive the aforementioned components therein. The cabinet body is configured in such a manner that the discharge opening (not designated by reference numeral) of the cabinet body 140 is in communication with the superheated vapor generation unit 120 through a duct (not designated by reference numeral) to cause the superheated vapor generated in the superheated vapor generation unit 120 to be exhausted to an indoor space through the discharge opening via operation of the blower 130 .
[0017] In addition, a semi-opening type cover 123 is installed to an upper end of the annular vessel 121 and serves to secondarily prevent leakage of the water received in the annular vessel 121 . An auxiliary fan 160 and an auxiliary heater 150 are further arranged in a vapor transfer path (duct) between the annular vessel 121 and the discharge opening and serve to ensure that a surrounding temperature of the discharge opening falls within a range of 100° C. to 150° C.
[0018] In addition, to reduce noise that may have a negative effect on organisms in consideration of the flow rate and pressure of the air blown by the blower 130 , a noise reduction device 124 is further installed in the vapor transfer path (duct) between the annular vessel 121 and the discharge opening. The noise reduction device 124 has a V-shaped or I-shaped cross section to maximize a sound absorption area.
[0019] At this time, with regard to positions of a water inlet line and a drain line suitable for continuous flow of water between the annular vessel 121 and the water supply unit 110 , as exemplarily illustrated in FIG. 1 , assuming that a height from the water inlet line to the drain line is designated by reference character A and a height from the drain line to the upper end of the inner sidewall of the annular vessel 121 is designated by reference character B, a relationship between these parameters A and B may be represented by “A≦B”.
[0020] In this way, in the germicidal heating apparatus using superheated vapor according to the present invention, as air from a predetermined space passes through the apparatus, the air is sterilized while passing through a space of the sheath heater 122 having the temperature of 600° C. or more and then is mixed with high temperature dry and pure vapor discharged from the annular vessel 121 that is installed to cool the sheath heater 122 , thereby producing aseptic greenhouse air good for organisms and causing an increase in room temperature owing to the vapor of high energy.
[0021] In addition, although the annular vessel 121 needs to ensure smooth fluid flow through use of an open circular outlet hole formed at the top thereof in order to generate sanitized hot air and purified high temperature dry vapor, it may be necessary to control the fluid flow to achieve sufficient fluid heating. Accordingly, as illustrated in the enlarged view of important parts of FIG. 1 , the upper end of the inner sidewall 121 B of the annular vessel is formed with the bent or protruding portion so as to come into close contact with the outer sidewall 121 A. In this way, the upper end of the inner sidewall 121 B and the outer sidewall 121 A of the annular vessel serve as a nozzle for discharge of the vapor.
[0022] The water stored in the water supply unit 110 may be directed to a water purifying device in order to minimize a hardening material that may prevent fluid flow. Therefore, a purifying/hydraulic pump device 17 including a water purifying device and a hydraulic motor may be installed upstream of a water supply line to ensure efficient supply of pure water required per unit time. The purifying device may be installed at the outside of the apparatus according to an installation position and may include one or more water purifying filters, for example, a primary filter, a secondary filter, an RO filter and a complex resin filter as well as a hydraulic motor according to the quality of supplied water. This configuration serves to minimize a hardening material, thereby preserving the lifespan of key components.
[0023] In addition, as can be expected, when the sheath heater 122 has a protruding configuration, it may be easily broken by external shock. Moreover, the sheath heater 122 may seem like a pillar of fire when viewed from the outside, thus stimulating children′ curiosity. Therefore, the annular vessel 121 may be designed so as not to protrude outward.
[0024] In addition, an electric device (not illustrated), which is provided to ensure an efficient operation of the germicidal heating apparatus using superheated vapor according to the present invention, is configured to achieve a desired effect using water. Therefore, the electric device requires a printed circuit board (PCB) control device attached thereto in order to maximize safety and, in turn, the PCB requires functionality for automatic control of external shock, gradient, superheating, and temperature of air to be discharged.
[0025] In addition, assuming that a thickness of the inner sidewall 121 B or the outer sidewall 121 A of the annular vessel is designated by reference character “a” and a distance of a space 121 C between the inner sidewall 121 B and the outer sidewall 121 A of the annular vessel is designated by reference character “b”, a relationship between these parameters “a” and “b” may be “b≦a”.
[0026] In addition, to achieve minimized heat loss as well as maximized usage of vapor and to prevent unwanted superheating inside the apparatus, at least one heat reserving member 125 formed of a ceramic material or other equivalent materials may be attached to the exterior of the annular vessel. At this time, a plurality of heat reserving members 125 may be aligned.
[0027] Although the preferred embodiment of the present invention has been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims and these modifications and variations should not be understood separately from the technical ideas or prospects of the present invention.
[0028] The present invention relates to a germicidal heating apparatus including a water supply unit configured to supply water, a superheated vapor generation unit configured to generate superheated vapor using the water supplied from the water supply unit, and a blower configured to blow the superheated vapor generated in the superheated vapor generation unit through a discharge opening. More particularly, the superheated vapor generation unit includes an annular vessel to receive the water supplied from the water supply unit and a spiral sheath heater provided at the entire inner peripheral surface of the annular vessel. An upper end of an inner sidewall of the annular vessel is bent so as to come into close contact with an outer sidewall in order to prevent leakage of the received water and to ensure discharge of vapor generated by heat of the sheath heater. Through provision of the germicidal heating apparatus using superheated vapor, air is sterilized while passing through a space of the sheath heater having the temperature of 600° C. or more and then is mixed with high temperature dry and pure vapor discharged from a cylindrical water vessel that is installed to cool the sheath heater, thereby producing aseptic greenhouse air good for organisms and causing an increase in indoor temperature owing to the vapor of high energy. Accordingly, the present invention has industrial availability in the fields of a heating apparatus.
|
A germicidal heating apparatus comprising a water supply part for supplying water, an superheated vapor generation part for generating superheated vapor by using the water supplied from the water supply part, and a blower for blowing the superheated vapor generated by the superheated vapor generation part through a discharge opening, characterized in that the superheated vapor generation part includes an annular vessel for receiving the water from the water supply part, and a spiral sheath heater arranged on the whole inside peripheral surface of the annular vessel, the upper end of the inside wall of the annular vessel being bent closely contacting the outside wall so as both to prevent leakage of the water contained in the annular vessel and to discharge the vapor generated by the heat of the sheath heater.
| 8
|
RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. patent application Ser. No. 12/969,367, filed Dec. 15, 2010, which is a divisional of U.S. patent application Ser. No. 12/263,120, filed Oct. 31, 2008, said patent applications hereby fully incorporated herein by reference.
GOVERNMENT FUNDING
[0002] This invention was made with government support under contract number N00014-07-C-0797 awarded by the Office of Navel Research (ONR). The United States Government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention is broadly concerned with novel compositions and methods of using those compositions to form bonding compositions that can support active wafers on a carrier wafer or substrate during wafer thinning and other processing.
[0005] 2. Description of the Prior Art
[0006] Wafer (substrate) thinning has been used to dissipate heat and aid in the electrical operation of integrated circuits (IC). Thick substrates cause an increase in capacitance, requiring thicker transmission lines, and, in turn, a larger IC footprint. Substrate thinning increases impedance while capacitance decreases impedance, causing a reduction in transmission line thickness, and, in turn, a reduction in IC size. Thus, substrate thinning facilitates IC miniaturization.
[0007] Geometrical limitations are an additional incentive for substrate thinning. Via holes are etched on the backside of a substrate to facilitate frontside contacts. In order to construct a via using common dry-etch techniques, geometric restrictions apply. For substrate thicknesses of less than 100 μm, a via having a diameter of 30-70 μm is constructed using dry-etch methods that produce minimal post-etch residue within an acceptable time. For thick substrates, vias with larger diameters are needed. This requires longer dry-etch times and produces larger quantities of post-etch residue, thus significantly reducing throughput. Larger vias also require larger quantities of metallization, which is more costly. Therefore, for backside processing, thin substrates can be processed more quickly and at lower cost.
[0008] Thin substrates are also more easily cut and scribed into ICs. Thinner substrates have a smaller amount of material to penetrate and cut and therefore require less effort. No matter what method (sawing, scribe and break, or laser ablation) is used, ICs are easier to cut from thinner substrates. Most semiconductor wafers are thinned after frontside operations. For ease of handling, wafers are processed (i.e., frontside devices) at their normal full-size thicknesses, e.g., 600-700 μm. Once completed, they are thinned to thicknesses of 100-150 μm. In some cases (e.g., when hybrid substrates such as gallium arsenide (GaAs) are used for high-power devices) thicknesses may be taken down to 25 μm.
[0009] Mechanical substrate thinning is performed by bringing the wafer surface into contact with a hard and flat rotating horizontal platter that contains a liquid slurry. The slurry may contain abrasive media along with chemical etchants such as ammonia, fluoride, or combinations thereof. The abrasive provides “gross” substrate removal, i.e., thinning, while the etchant chemistry facilitates “polishing” at the submicron level. The wafer is maintained in contact with the media until an amount of substrate has been removed to achieve a targeted thickness.
[0010] For a wafer thickness of 300 μm or greater, the wafer is held in place with tooling that utilizes a vacuum chuck or some means of mechanical attachment. When wafer thickness is reduced to less than 300 μm, it becomes difficult or impossible to maintain control with regard to attachment and handling of the wafer during further thinning and processing. In some cases, mechanical devices may be made to attach and hold onto thinned wafers, however, they are subject to many problems, especially when processes may vary. For this reason, the wafers (“active” wafers) are mounted onto a separate rigid (carrier) substrate or wafer. This substrate becomes the holding platform for further thinning and post-thinning processing. Carrier substrates are composed of materials such as sapphire, quartz, certain glasses, and silicon, and usually exhibit a thickness of 1000 μm. Substrate choice will depend on how closely matched the coefficient of thermal expansion (CTE) is between each material. However, most of the currently available adhesion methods do not have adequate thermal or mechanical stability to withstand the high temperatures encountered in backside processing steps, such as metallization or dielectric deposition and annealing. Many current methods also have poor planarity (which contributes excessive total thickness variation across the wafer dimensions), and poor chemical resistance.
[0011] One method that has been used to mount an active wafer to a carrier substrate is via a thermal release adhesive tape. This process has two major shortcomings. First, the tapes have limited thickness uniformity across the active wafer/carrier substrate interface, and this limited uniformity is often inadequate for ultra-thin wafer handling. Second, the thermal release adhesive softens at such low temperatures that the bonded wafer/carrier substrate stack cannot withstand many typical wafer processing steps that are carried out at higher temperatures.
[0012] Thermally stable adhesives, on the other hand, often require excessively high bonding pressures or bonding temperatures to achieve sufficient melt flow for good bond formation to occur. Likewise, too much mechanical force may be needed to separate the active wafer and carrier wafer because the adhesive viscosity remains too high at practical debonding temperatures. Thermally stable adhesives can also be difficult to remove without leaving residues.
[0013] There is a need for new compositions and methods of adhering an active wafer to a carrier substrate that can endure high processing temperatures and that allow for ready separation of the wafer and substrate at the appropriate stage of the process.
SUMMARY OF THE INVENTION
[0014] The present invention overcomes the problems of the prior art by broadly providing a wafer bonding method, which includes providing a stack comprising first and second substrates bonded together via a bonding layer, and separating the first and second substrates. The bonding layer is formed from a composition comprising a cycloolefin copolymer (COC) dissolved or dispersed in a solvent system.
[0015] The invention also provides an article comprising first and second substrates and a bonding layer. The first substrate comprises a back surface and an active surface, which comprises at least one active site and a plurality of topographical features. The second substrate has a bonding surface. The bonding layer is bonded to the active surface of the first substrate and to the bonding surface of the second substrate. The bonding layer is formed from a composition comprising a cycloolefin copolymer dissolved or dispersed in a solvent system.
[0016] In a further embodiment, the invention is concerned with a composition useful for bonding two substrates together. The inventive composition comprises a cycloolefin copolymer and an ingredient dissolved or dispersed in a solvent system. The ingredient is selected from the group consisting of tackifier resins, low molecular weight cycloolefin copolymers, and mixtures thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure (FIG.) 1 illustrates the inventive method of thinning and debonding two wafers according to the present invention;
[0018] FIG. 2 is a flow diagram showing the typical process steps followed in the examples;
[0019] FIG. 3 is a graph depicting the rheological analysis results of bonding compositions according to the invention debonded at 150° C.;
[0020] FIG. 4 is a graph depicting the rheological analysis results for bonding compositions according to the invention debonded at 200° C.; and
[0021] FIG. 5 is a graph depicting the rheological analysis results for bonding compositions according to the invention debonded at 250° C.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] In more detail, the inventive compositions comprise a cycloolefin copolymer (COC) dispersed or dissolved in a solvent system. The copolymer is preferably present in the composition at levels of from about 5% to about 85% by weight, more preferably from about 5% to about 60% by weight, and most preferably from about 10% to about 40% by weight, based upon the total weight of the composition taken as 100% by weight.
[0023] The preferred copolymers are thermoplastic and preferably have a weight average molecular weight (M W ) of from about 2,000 Daltons to about 200,000 Daltons, and more preferably from about 5,000 Daltons to about 100,000 Daltons. Preferred copolymers preferably have a softening temperature (melt viscosity at 3,000 Pa·S) of at least about 100° C., more preferably at least about 140° C., and even more preferably from about 160° C. to about 220° C. Suitable copolymers also preferably have a glass transition temperature (T g ) of at least about 60° C., more preferably from about 60° C. to about 200° C., and most preferably from about 75° C. to about 160° C.
[0024] Preferred cycloolefin copolymers are comprised of recurring monomers of cyclic olefins and acyclic olefins, or ring-opening polymers based on cyclic olefins. Suitable cyclic olefins for use in the present invention are selected from the group consisting of norbornene-based olefins, tetracyclododecene-based olefins, dicyclopentadiene-based olefins, and derivatives thereof. Derivatives include alkyl (preferably C 1 -C 20 alkyls, more preferably C 1 -C 10 alkyls), alkylidene (preferably C 1 -C 20 alkylidenes, more preferably C 1 -C 10 alkylidenes), aralkyl (preferably C 6 -C 30 aralkyls, more preferably C 6 -C 18 aralkyls), cycloalkyl (preferably C 3 -C 30 cycloalkyls, more preferably C 3 -C 18 cycloalkyls), ether, acetyl, aromatic, ester, hydroxy, alkoxy, cyano, amide, imide, and silyl-substituted derivatives. Particularly preferred cyclic olefins for use in the present invention include those selected from the group consisting of
[0000]
[0000] and combinations of the foregoing, where each R 1 and R 2 is individually selected from the group consisting of —H, and alkyl groups (preferably C 1 -C 20 alkyls, more preferably C 1 -C 10 alkyls), and each R 3 is individually selected from the group consisting of —H, substituted and unsubstituted aryl groups (preferably C 6 -C 18 aryls), alkyl groups (preferably C 1 -C 20 alkyls, more preferably C 1 -C 10 alkyls), cycloalkyl groups (preferably C 3 -C 30 cycloalkyl groups, more preferably C 3 -C 18 cycloalkyl groups), aralkyl groups (preferably C 6 -C 30 aralkyls, more preferably C 6 -C 18 aralkyl groups such as benzyl, phenethyl, and phenylpropyl, etc.), ester groups, ether groups, acetyl groups, alcohols (preferably C 1 -C 10 ) alcohols), aldehyde groups, ketones, nitriles, and combinations thereof.
[0025] Preferred acyclic olefins are selected from the group consisting of branched and unbranched C 2 -C 20 alkenes (preferably C 2 -C 10 alkenes). More preferably, suitable acyclic olefins for use in the present invention have the structure
[0000]
[0000] where each R 4 is individually selected from the group consisting of —H and alkyl groups (preferably C 1 -C 20 alkyls, more preferably C 1 -C 10 alkyls). Particularly preferred acyclic olefins for use in the present invention include those selected from the group consisting of ethene, propene, and butene, with ethene being the most preferred.
[0026] Methods of producing cycloolefin copolymers are known in the art. For example, cycloolefin copolymers can be produced by chain polymerization of a cyclic monomer with an acyclic monomer (such as norbornene with ethene as shown below).
[0000]
[0000] The reaction shown above results in an ethene-norbornene copolymer containing alternating norbornanediyl and ethylene units. Examples of copolymers produced by this method include TOPAS®, produced by Goodfellow Corporation and TOPAS Advanced Polymers, and APEL®, produced by Mitsui Chemicals. A suitable method for making these copolymers is disclosed in U.S. Pat. No. 6,008,298, incorporated by reference herein.
[0027] Cycloolefin copolymers can also be produced by ring-opening metathesis polymerization of various cyclic monomers followed by hydrogenation as illustrated below.
[0000]
[0000] The polymers resulting from this type of polymerization can be thought of conceptually as a copolymer of ethene and a cyclic olefin monomer (such as alternating units of ethylene and cyclopentane-1,3-diyl as shown below).
[0000]
[0000] Examples of copolymers produced by this method include ZEONOR® from Zeon Chemicals, and ARTON® from JSR Corporation. A suitable method of making these copolymers is disclosed in U.S. Pat. No. 5,191,026, incorporated by reference herein.
[0028] Accordingly, copolymers of the present invention preferably comprise recurring monomers of:
[0000]
[0029] and combinations of the foregoing, where:
each R 1 and R 2 is individually selected from the group consisting of —H, and alkyl groups (preferably C 1 -C 20 alkyls, more preferably C 1 -C 10 alkyls), and each R 3 is individually selected from the group consisting of —H, substituted and unsubstituted aryl groups (preferably C 6 -C 18 aryls), alkyl groups (preferably C 1 -C 20 alkyls, more preferably C 1 -C 10 alkyls), cycloalkyl groups (preferably C 3 -C 30 cycloalkyl groups, more preferably C 3 -C 18 cycloalkyl groups), aralkyl groups (preferably C 6 -C 30 aralkyls, more preferably C 6 -C 18 aralkyl groups, such as benzyl, phenethyl, and phenylpropyl, etc.), ester groups, ether groups, acetyl groups, alcohols (preferably C 1 -C 10 alcohols), aldehyde groups, ketones, nitriles, and combinations thereof;
and
[0032] (II):
[0000]
[0033] where:
- - - - - is a single or double-bond; and each R 4 is individually selected from the group consisting of —H and alkyl groups (preferably C 1 -C 20 alkyls, more preferably C 1 -C 10 alkyls).
[0036] The ratio of monomer (I) to monomer (II) within the polymer is preferably from about 5:95 to about 95:5, and more preferably from about 30:70 to about 70:30.
[0037] The inventive compositions are formed by simply mixing the cycloolefin copolymer and any other ingredients with the solvent system, preferably at room temperature to about 150° C., for time periods of from about 1-72 hours.
[0038] The composition should comprise at least about 15% by weight solvent system, preferably from about 30% to about 95% by weight solvent system, more preferably from about 40% to about 90% by weight solvent system, and even more preferably from about 60% to about 90% by weight solvent system, based upon the total weight of the composition taken as 100% by weight. The solvent system should have a boiling point of from about 50-280° C., and preferably from about 120-250° C. Suitable solvents include, but are not limited to, methyl ethyl ketone (MEK) and cyclopentanone, as well as hydrocarbon solvents selected from the group consisting of limonene, mesitylene, dipentene, pinene, bicyclohexyl, cyclododecene, 1-tert-butyl-3,5-dimethylbenzene, butylcyclohexane, cyclooctane, cycloheptane, cyclohexane, methylcyclohexane, and mixtures thereof.
[0039] The total solids level in the composition should be at least about 5% by weight, preferably from about 5% to about 85% by weight, more preferably from about 5% to about 60% by weight, and even more preferably from about 10% to about 40% by weight, based upon the total weight of the composition taken as 100% by weight.
[0040] According to the invention, the composition can include additional ingredients, including low molecular weight cycloolefin copolymer (COC) resins and/or tackifier resins or rosins. The composition can also include a number of optional ingredients selected from the group consisting of plasticizers, antioxidants, and mixtures thereof.
[0041] When a low molecular weight COC resin is used in the composition, it is preferably present in the composition at a level of from about 2% to about 80% by weight, more preferably from about 5% to about 50% by weight, and even more preferably from about 15% to about 35% by weight, based upon the total weight of the composition taken as 100% by weight. The term “low molecular weight cycloolefin copolymer” is intended to refer to COCs having a weight average molecular weight (M w ) of less than about 50,000 Daltons, preferably less than about 20,000 Daltons, and more preferably from about 500 to about 10,000 Daltons. Such copolymers also preferably have a T g of from about 50° C. to about 120° C., more preferably from about 60° C. to about 90° C., and most preferably from about 60° C. to about 70° C. Exemplary low molecular weight COC resins for use in the present compositions are those sold under the name TOPAS® Toner TM (M w 8,000), available from Topas Advanced Polymers.
[0042] When a tackifier or rosin is utilized, it is preferably present in the composition at a level of from about 2% to about 80% by weight, more preferably from about 5% to about 50% by weight, and even more preferably from about 15% to about 35% by weight, based upon the total weight of the composition taken as 100% by weight. The tackifiers are chosen from those having compatible chemistry with the cycloolefin copolymers so that no phase separation occurs in the compositions. Examples of suitable tackifiers include, but are not limited to, polyterpene resins (sold under the name SYLVARES™ TR resin; Arizona Chemical), beta-polyterpene resins (sold under the name SYLVARES™ TR-B resin; Arizona Chemical), styrenated terpene resins (sold under the name ZONATAC NG resin; Arizona Chemical), polymerized rosin resins (sold under the name SYLVAROS® PR resin; Arizona Chemical), rosin ester resins (sold under the name EASTOTAC™ resin; Eastman Chemical), cyclo-aliphatic hydrocarbon resins (sold under the name PLASTOLYN™ resin; Eastman Chemical, or under the name ARKON™ resin; Arakawa Chemical), C5 aliphatic hydrocarbon resins (sold under the name PICCOTAC™ resin; Eastman Chemical), hydrogenated hydrocarbon resins (sold under the name REGALITE™ resin; Eastman Chemical), and mixtures thereof.
[0043] When an antioxidant is utilized, it is preferably present in the composition at a level of from about 0.1% to about 2% by weight, and more preferably from about 0.5% to about 1.5% by weight, based upon the total weight of the composition taken as 100% by weight. Examples of suitable antioxidants include those selected from the group consisting of phenolic antioxidants (such as pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate sold under the name IRGANOX® 1010 by Ciba), phosphite antioxidants (such as tris(2,4-ditert-butylphenyl)phosphite sold under the name IRGAFOS® 168 by Ciba), phosphonite antioxidants (such as tetrakis(2,4-di-tert-butylphenyl)[1,1-biphenyl]-4,4t-diylbisphosphonite sold under the name IRGANOX® P-EPQ by Ciba), and mixtures thereof.
[0044] In alternative embodiments, it is preferred that the compositions are essentially free (less than about 0.1% and preferably about 0% by weight) of adhesion promoting agents, such as bis(trimethoxysilylethyl)benzene, aminopropyl tri(alkoxy silanes) (e.g., aminopropyl tri(methoxy silane), aminopropyl tri(ethoxy silanes), phenyl aminopropyl tri(ethoxy silane)), and other silane coupling agents, or mixtures thereof. In some embodiments, the final composition is also thermoplastic (i.e., noncrosslinkable). Thus, in these alternative embodiments, the composition will be essentially free (less than about 0.1% by weight and preferably about 0% by weight) of crosslinking agents, such as POWDERLINK® by Cytec, and EPI-CURE™ 3200 by Hexion Specialty Chemicals.
[0045] According to one aspect, the melt viscosity (complex coefficient of viscosity) of the final composition will preferably be less than about 100 Pa·S, more preferably less than about 50 Pa·S, and even more preferably from about 1 Pa·S to about 35 Pa·S. For purposes of these measurements, the melt viscosity is determined via rheological dynamic analysis (TA Instruments, AR-2000, two parallel-plate configuration where the plates have a diameter of 25 mm). Furthermore, the melt viscosity is preferably determined at the preferred debonding temperature of the composition in question. As used herein, the term “preferred debonding temperature” of the composition is defined as the temperature at which the melt viscosity of the composition is below 100 Pa·S, and is determined by dynamic measurement at 1 Hz oscillation frequency in temperature ramp. The compositions also preferably have a storage modulus (G′) of less than about 100 Pa, preferably less than about 50 Pa, and even more preferably from about 1 Pa to about 26 Pa, when measured at the preferred debonding temperature of the composition. The storage modulus is determined by dynamic measurement at 1 Hz oscillation frequency in temperature ramp.
[0046] The compositions are thermally stable up to about 350° C. There is also preferably less than about 5% by weight, and more preferably less than about 1.5% by weight, loss of the composition after one hour at the preferred debonding temperature plus 50° C. (preferably at a temperature of from about 200° C. to about 300° C.), depending upon the composition. In other words, very little to no thermal decomposition occurs in the composition at this temperature, as determined by thermogravimetric analysis (TGA), described herein.
[0047] Although the composition could be applied to either the carrier substrate or active wafer first, it is preferred that it be applied to the active wafer first. These compositions can be coated to obtain void-free thick films required for bump wafer applications and to achieve the required uniformity across the wafer. A preferred application method involves spin-coating the composition at spin speeds of from about 500-5000 rpm (more preferably from about 1000-3500 rpm), at accelerations of from about 3000-10,000 rpm/second, and for spin times of from about 30-180 seconds. It will be appreciated that the application steps can be varied to achieve a particular thickness.
[0048] After coating, the substrate can be baked (e.g., on a hot plate) to evaporate the solvents. Typical baking would be at temperatures of from about 70-250° C., and preferably from about 80-240° C. for a time period of from about 1-60 minutes, and more preferably from about 2-10 minutes. The film thickness (on top of the topography) after bake will typically be at least about 1 μm, and more preferably from about 10-200 μm.
[0049] After baking, the desired carrier wafer is contacted with, and pressed against, the layer of inventive composition. The carrier wafer is bonded to this inventive composition by heating at a temperature of from about 100-300° C., and preferably from about 120-180° C. This heating is preferably carried out under vacuum and for a time period of from about 1-10 minutes, under a bond force of from about 0.1 to about 25 kiloNewtons. The bonded wafer can be subjected to backgrinding, metallization, patterning, passivation, via forming, and/or other processing steps involved in wafer thinning, as explained in more detail below.
[0050] FIG. 1( a ) illustrates an exemplary stack 10 comprising active wafer 12 and carrier wafer or substrate 14 . It will be appreciated that stack 10 is not shown to scale and has been exaggerated for the purposes of this illustration. Active wafer 12 has an active surface 18 . As shown in FIG. 1( a ), active surface 18 can comprise various topographical features 20 a - 20 d. Typical active wafers 12 can include any microelectronic substrate. Examples of some possible active wafers 12 include those selected from the group consisting of microelectromechanical system (MEMS) devices, display devices, flexible substrates (e.g., cured epoxy substrates, roll-up substrates that can be used to form maps), compound semiconductors, low k dielectric layers, dielectric layers (e.g., silicon oxide, silicon nitride), ion implant layers, and substrates comprising silicon, aluminum, tungsten, tungsten silicide, gallium arsenide, germanium, tantalum, tantalum nitrite, SiGe, and mixtures of the foregoing.
[0051] Carrier substrate 14 has a bonding surface 22 . Typical carrier substrates 14 comprise a material selected from the group consisting of sapphire, ceramic, glass, quartz, aluminum, silver, silicon, glass-ceramic composites (such as products sold under the name Zerodur®, available from Schott AG), and combinations thereof.
[0052] Wafer 12 and carrier substrate 14 are bonded together via bonding composition layer 24 . Bonding layer 24 is formed of the cycloolefin copolymer compositions described above, and has been applied and dried as also described above. As shown in the FIG. 1( a ), bonding layer 24 is bonded to active surface 18 of wafer 12 as well as to bonding surface 22 of substrate 14 . Unlike prior art tapes, bonding layer 24 is a uniform (chemically the same) material across its thickness. In other words, the entire bonding layer 24 is formed of the same composition.
[0053] It will be appreciated that, because bonding layer 24 can be applied to active surface 18 by spin-coating or spray-coating, the bonding composition flows into and over the various topographical features. Furthermore, the bonding layer 24 forms a uniform layer over the topography of active surface 18 . To illustrate this point, FIG. 1 shows a plane designated by dashed line 26 , at end portion 21 and substantially parallel to back surface 16 . The distance from this plane to bonding surface 22 is represented by the thickness “T.” The thickness “T” will vary by less than about 20%, preferably by less than about 10%, more preferably by less than about 5%, even more preferably by less than about 2%, and most preferably less than about 1% across the length of plane 26 and substrate 14 .
[0054] The wafer package can then be subjected to subsequent thinning (or other processing) of the substrate as shown in FIG. 1( b ), where 12 ′ presents the wafer 12 after thinning. It will be appreciated that the substrates can be thinned to thicknesses of less than about 100 μm, preferably less than about 50 μm, and more preferably less than about 25 μm. After thinning, typical backside processing, including backgrinding, patterning (e.g., photolithography, via etching), passivation, and metallization, and combinations thereof, may be performed.
[0055] Advantageously, the dried layers of the inventive compositions possess a number of highly desirable properties. For example, the layers will exhibit low outgassing for vacuum etch processes. That is, if a 15-μm thick film of the composition is baked at 80-250° C. for 2-60 minutes (more preferably 2-4 minutes), the solvents will be driven from the composition so that subsequent baking at 140-300° C. for 2-4 minutes results in a film thickness change of less than about 5%, preferably less than about 2%, and even more preferably less than about 1.0% or even 0% (referred to as the “Film Shrinkage Test”). Thus, the dried layers can be heated to temperatures of up to about 350° C., preferably up to about 320° C., more preferably up to about 300° C., without chemical reactions occurring in the layer. In some embodiments, the layers can also be exposed to polar solvents (e.g., N-methyl-2-pyrrolidone) at a temperature of 80° C. for 15 minutes without reacting.
[0056] The bond integrity of the dried layers can be maintained even upon exposure to an acid or base. That is, a dried layer of the composition having a thickness of about 15 μm can be submerged in an acidic media (e.g., concentrated sulfuric acid) or base (e.g., 30 wt. % KOH) at 85° C. for about 45 minutes while maintaining bond integrity. Bond integrity can be evaluated by using a glass carrier substrate and visually observing the bonding composition layer through the glass carrier substrate to check for bubbles, voids, etc. Also, bond integrity is maintained if the active wafer and carrier substrate cannot be separated by hand.
[0057] After the desired processing has occurred, the active wafer or substrate can be separated from the carrier substrate. In one embodiment, the active wafer and substrate are separated by heating to a temperature sufficient to soften the bonding layer. More specifically, the stack is heated to temperatures of at least about 100° C., preferably at least about 120° C., and more preferably from about 150° C. to about 300° C. These temperature ranges represent the preferred debonding temperatures of the bonding composition layer. This heating will cause the bonding composition layer to soften and form softened bonding composition layer 24 ′ as shown in FIG. 1( c ), at which point the two substrates can be separated, for example, by sliding apart. FIG. 1( c ) shows an axis 28 , which passes through both of wafer 12 and substrate 14 , and the sliding forces would be applied in a direction generally transverse to axis 28 . Instead of sliding, wafer 12 or substrate 14 can be separated by lifting upward (i.e., in a direction that is generally away from the other of wafer 12 or substrate 14 ) to separate the wafer 12 from the substrate 14 .
[0058] Alternatively, instead of heating to soften the layer, the bonding composition can be dissolved using a solvent. Once the layer is dissolved, the active wafer and substrate can be thereafter separated. Suitable solvents for use in dissolving the bonding layer can be any solvent that was part of the composition prior to drying, such as those selected from the group consisting of MEK and cyclopentanone, as well as hydrocarbon solvents selected from the group consisting of limonene, mesitylene, dipentene, pinene, bicyclohexyl, cyclododecene, 1-tert-butyl-3,5-dimethylbenzene, butylcyclohexane, cyclooctane, cycloheptane, cyclohexane, methylcyclohexane, and mixtures thereof.
[0059] Whether the bonding composition is softened or dissolved, it will be appreciated that separation can be accomplished by simply applying force to slide and/or lift one of wafer 12 or substrate 14 while maintaining the other in a substantially stationary position so as to resist the sliding or lifting force (e.g., by applying simultaneous opposing sliding or lifting forces to wafer 12 and substrate 14 ). This can all be accomplished via conventional equipment.
[0060] Any bonding composition remaining in the device areas can be easily removed by rinsing with a suitable solvent followed by spin-drying. Suitable solvents include the original solvent that was part of the composition prior to drying as well as those solvents listed above suitable for dissolving the composition during debonding. Any composition remaining behind will be completely dissolved (at least about 98%, preferably at least about 99%, and more preferably about 100%) after 5-15 minutes of exposure to the solvent. It is also acceptable to remove any remaining bonding composition using a plasma etch, either alone or in combination with a solvent removal process. After this step, a clean, bonding composition-free wafer 12 ′ and carrier substrate 14 (not shown in their clean state) will remain.
EXAMPLES
[0061] The following examples set forth preferred methods in accordance with the invention. It is to be understood, however, that these examples are provided by way of illustration and nothing therein should be taken as a limitation upon the overall scope of the invention.
Example 1
Cycloolefin Copolymer Resin and Low Molecular Weight COC Resin Blends
[0062] In this Example, formulations containing cycloolefin copolymers and a low molecular weight COC resin were made. Antioxidants were added to some of the formulations.
[0063] 1. Sample 1.1
[0064] In this procedure, 1.2 grams of an ethene-norbornene copolymer (TOPAS® 5010, T g 110° C.; obtained from TOPAS Advanced Polymers, Florence, Ky.) were dissolved in 6 grams of D-limonene (Florida Chemical Co.), along with 2.8 grams of a low molecular weight cycloolefin copolymer (TOPAS® Toner TM, M w 8,000, M w /M n 2.0). The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
[0065] 2. Sample 1.2
[0066] In this procedure, 0.75 grams of an ethene-norbornene copolymer (TOPAS® 8007, T g 78° C.) and 3.25 grams of low molecular weight COC (TOPAS® Toner TM) were dissolved in 6 grams of D-Iimonene. The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
[0067] 3. Sample 1.3
[0068] For this procedure, 1.519 grams of an ethene-norbomene copolymer (TOPAS® 5013, T g 134° C.) were dissolved in 5.92 grams of D-limonene along with 2.481 grams of a low molecular weight cycloolefin copolymer (TOPAS® Toner TM), 0.04 grams of a phenolic antioxidant (IRGANOX® 1010), and 0.04 grams of a phosphonite antioxidant (IRGAFOX® P-EPQ). The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
[0069] 4. Sample 1.4
[0070] In this procedure, 1.2 grams of an ethene-norbornene copolymer (TOPAS® 8007) were dissolved in 5.92 grams of D-limonene along with 2.8 grams of a low molecular weight cycloolefin copolymer (TOPAS® Toner TM), 0.04 grams of a phenolic antioxidant (IRGANOX® 1010), and 0.04 grams of a phosphonite antioxidant (IRGAFOX® P-EPQ). The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
[0071] 5. Sample 1.5
[0072] For this procedure, 2.365 grams of an ethene-norbornene copolymer (TOPAS® 5013) were dissolved in 5.92 grams of D-limonene along with 1.635 grams of a low molecular weight cycloolefin copolymer (TOPAS® Toner TM), 0.04 grams of a phenolic antioxidant (IRGANOX® 1010), and 0.04 grams of a phosphonite antioxidant (IRGAFOX® P-EPQ). The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
[0073] 6. Sample 1.6
[0074] In this procedure, 2.2 grams of a hydrogenated norbornene-based copolymer prepared by ring-opening polymerization (ZEONOR® 1060, T g 100° C.; obtained from Zeon Chemicals, Louisville, Ky.) and 1.8 grams of a low molecular weight cycloolefin copolymer (TOPAS® Toner TM) were dissolved in 5.92 grams of cyclooctane (Aldrich, Milwaukee, Wis.). The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
Example 2
Cycloolefin Copolymer Resins and Tackifier Blends
[0075] In this Example, formulations were made containing cycloolefin copolymers blended with various tackifiers. As in Example 1, antioxidants were added to some of the formulations.
[0076] 1. Sample 2.1
[0077] In this procedure, 0.83 grams of an ethene-norbomene copolymer (TOPAS® 8007) were dissolved in 5.92 grams of D-limonene, along with 3.17 grams of a hydrogenated hydrocarbon resin (REGALITE® R1125; obtained from Eastman Chemical Co., Kingsport Tenn.), 0.04 grams of a phenolic antioxidant (IRGANOX® 1010), and 0.04 grams of a phosphonite antioxidant (IRGAFOX® P-EPQ). The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
[0078] 2. Sample 2.2
[0079] For this procedure, 0.7 grams of an ethene-norbornene copolymer (TOPAS® 8007) and 3.3 grams of a styrenated terpene resin (ZONATAC® NG98; obtained from Arizona Chemical, Jacksonville, Fla.) were dissolved in 5.92 grams of D-limonene, along with 0.04 grams of a phenolic antioxidant (IRGANOX® 1010), and 0.04 grams of a phosphonite antioxidant (IRGAFOX® P-EPQ). The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
[0080] 3. Sample 2.3
[0081] In this formulation, 1.9 grams of an ethene-norbornene copolymer (TOPAS® 5013) were dissolved in 5.92 grams of D-limonene, along with 2.1 grams of a cyclo-aliphatic hydrocarbon resin (ARKON® P-140; obtained from Arakawa Chemical USA Inc., Chicago, Ill.), 0.04 grams of a phenolic antioxidant (IRGANOX® 1010), and 0.04 grams of a phosphonite antioxidant (IRGAFOX® P-EPQ). The solution was allowed to stir at room temperature until the ingredients were in solution.
[0082] 4. Sample 2.4
[0083] For this procedure, 2.42 grams of an ethene-norbornene copolymer (TOPAS® 5013) were dissolved in 5.92 grams of D-limonene, along with 1.58 grams of a cyclo-aliphatic hydrocarbon resin (PLASTOLYN® R-1140; obtained from Arakawa Chemical USA Inc., Chicago, Ill.), 0.04 grams of a phenolic antioxidant (IRGANOX® 1010), and 0.04 grams of a phosphonite antioxidant (IRGAFOX® P-EPQ). The solution was allowed to stir at room temperature until the ingredients were in solution. The solution had about 40% solids.
Example 3
Application, Bonding and Debonding, and Analysis
[0084] The formulations prepared in Examples 1 and 2 above were spin-coated onto various substrate wafers. After baking to evaporate the solvent and allowing the bonding composition to reflow, a second wafer was bonded to each coated wafer by applying pressure. A typical procedure for temporary wafer bonding using the bonding compositions is illustrated in FIG. 2 . The bonded wafers were tested for mechanical strength, thermal stability, and chemical resistance. The wafers were tested for debonding by manually sliding them apart at acceptable temperatures. After debonding, the bonding composition residue was cleaned using a solvent rinse and spinning.
[0085] The rheological properties of each formulation from Examples 1 and 2 were tested. All of these materials were successfully tested for debonding. It was determined that the preferred debonding temperature for samples 1.1, 1.2, 2.1, and 2.2 was 150° C. The preferred debonding temperature for samples 1.3, 1.4, and 2.3 was 200° C., and the preferred debonding temperature for samples 1.5, 1.6, and 2.4 was 250° C. The storage modulus (G′) and melt viscosity (η*, complex coefficient of viscosity) for each sample at their preferred debonding temperatures are reported below. The rheological data is also illustrated in FIGS. 3-5 for each debonding temperature.
[0000]
TABLE 1
Sample
Storage Modulus, G′
Viscosity, η*
Debonding
number
(Pa)
(Pa · s)
Temperature (° C.)
1.1
25.5
35.0
150
1.2
9.6
16.7
150
1.3
8.0
13.9
200
1.4
3.5
5.1
200
1.5
16.3
20.1
250
1.6
8.1
15.1
250
2.1
24.9
14.5
150
2.2
1.3
2.4
150
2.3
21.7
28.7
200
2.4
5.5
14.1
250
[0086] Further studies on thermal stability and chemical resistance were also carried out on these compositions. Thermogravimetric analysis (TGA) was carried out on a TA Instruments thermogravimetric analyzer. The TGA samples were obtained by scraping off the spin-coated and baked bonding composition samples from Examples 1 and 2. For the isothermal TGA measurement, the samples were heated in nitrogen at a rate of 10° C./min., up to their preferred debonding temperature plus 50° C., and kept constant at that temperature for 1 hour to determine the thermal stability of the particular bonding composition. The isothermal measurements for each sample formulation are reported below in Table 2. For the scanning TGA measurement, the samples were heated in nitrogen at a rate of 10° C./min. from room temperature to 650° C.
[0000]
TABLE 2
Isothermal thermogravimetric results - thermal stability (in N 2 )
Weight Loss (%)
Isothermal
Sample
(Isothermal for 1 hour)
temperature (° C.)
1.1
0.123
200
1.2
0.847
200
1.3
1.268
250
1.4
0.764
250
1.5
0.752
300
1.6
0.596
300
2.1
5.496
200
2.2
4.650
200
2.3
5.737
250
2.4
5.191
300
[0087] As can be seen from the Table above, all of the COC-low molecular weight COC resin blends (Example 1) possessed the required thermal stability at least up to 300° C. and exhibited minimal weight loss (<1.5-wt %). The COC-tackifier blends (Example 2) had an average weight loss of about 5-wt % when maintained at the testing temperature. However, as shown in Table 3, below, the 1-wt % weight loss temperatures were higher than their respective bonding/debonding temperatures, suggesting sufficient thermal resistance for wafer-bonding applications.
[0000]
TABLE 3
Scanning thermogravimetric results
Temperature at 1.0%
Debonding
Sample
weight loss (° C.)
Temperature (° C.)
2.1
214
150
2.2
223
150
2.3
228
200
2.4
252
250
[0088] To determine chemical resistance, two silicon wafers were bonded using the particular bonding composition to be tested. The bonded wafers were put into chemical baths of N-Methyl-2-Pyrrolidone (NMP) or 30% by weight KOH at 85° C., and concentrated sulfuric acid at room temperature to determine chemical resistance. The bond integrity was visually observed after 45 minutes, and the stability of the bonding composition against the respective chemical was determined. All bonding compositions retained the bond integrity.
|
New compositions and methods of using those compositions as bonding compositions are provided. The compositions comprise a cycloolefin copolymer dispersed or dissolved in a solvent system, and can be used to bond an active wafer to a carrier wafer or substrate to assist in protecting the active wafer and its active sites during subsequent processing and handling. The compositions form bonding layers that are chemically and thermally resistant, but that can also be softened or dissolved to allow the wafers to slide or be pulled apart at the appropriate stage in the fabrication process.
| 8
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a sample stage in the head of a scanning probe microscope, such as a scanning tunneling microscope (referred to as an STM hereinafter) or an atomic force microscope (referred to as an ATM hereinafter), and more particularly, to a sample stage capable of getting a sample plane to change direction by using a flexible shaft.
2. Description of the Related Art
STM head sample stages needed to coarsely focus on samples, heat sample planes and replace samples have been disclosed heretofore, for example, in the following documents:
1. M. Ringger, B. W. Corb., H. R. Hidber, R. Schlogl, R. Weisendanger, A. Stemmer, L. Rosenthaler, A. J. Brunner, P. C. Oelhafen and H. J. Gruntherodt: IBM J. Res. Develop., Vol. 30, No. 5, pp. 500-508, 1986.
2. Th. Berghaus, H. Neddermeyer and St. Tosch: IBM J. Res. Develop., Vol. 30, No. 5, pp. 520-524, 1986.
3. S. Chiang, R. J. Wilson, Ch. Gerber and V. M. Hallmark: J. Vac. Sci. Technol. A, Vol. 6, No. 2, pp.386-389, 1988.
4. J. E. Demuth, R. J. Hamers, R. M. Tromp and M. E. Welland: J. Vac. Sci. Technol. A, Vol. 4, No. 3, pp. 1320-1323, 1986.
5. M. Okano, K. Kajimura, S. Wakiyama, F. Sakai, W. Mizutani and M. Ono: J. Vac. Sci. Technol. A, Vol. 5, No. 6, pp. 1313-3320, 1987.
6. H. Bando, H. Tokumoto, A. Zettl and K. Kajimura: Ultramicroscopy, No. 42-44, pp. 1627-1631, 1992.
A typical example of such conventional sample stages is illustrated in FIG. 28. This sample stage has a plurality of piezoelectric plates 52 supported by three legs 51 and a sample carrier 53 mounted on one of the piezoelectric plates 52. The legs 51 are made to move like a looper by applying driving voltage to the piezoelectric plates 52, thereby getting a sample plane 53a to change direction. FIG. 29A illustrates another conventional sample stage. This sample stage is provided with a running arm 55 pivotally mounted to a movable rod 56 by a connecting pin 54, and a sample carrier 58 is formed at one end of the running arm 55. On the side of the other end of the running arm 55, a stopper 57 is fixed to the sample stage. In this sample stage, the direction of a sample plane 58a is changed by linearly moving the movable rod 56 upward together with the connecting pin 54 from the state shown in FIG. 29A and pivoting one end of the running arm 55, at which the sample carrier 58 is mounted, upward about the stopper 57 in contact with the other end of the running arm 55, as shown in FIG. 29B.
However, the above-mentioned conventional sample stages have the following problems. Since the sample plane 53a is moved-by extending and contracting the plural piezoelectric plates 52 by the voltage application in the sample stage shown in FIG. 28, it takes a long time to change the direction of the sample plane 53a over a wide range. Furthermore, the method of applying the drive voltage to the plural piezoelectric plates 52 is complicated, and the directional change is unstable since the coefficient of friction of the bottom surface of each arm 51 is liable to change.
On the other hand, in the sample stage illustrated in FIG. 29, since the running arm 55 is mounted pivotally in a vertical plane by the connecting pin 54, the direction of the sample plane 58a can be also changed only in a vertical plane.
SUMMARY OF THE INVENTION
The present invention aims to solve these problems, and it is an object of the present invention to provide a sample stage of a scanning probe microscope capable of changing the direction of a sample plane stably over a wide range in a simple operation.
In order to achieve the above object, there is provided a sample stage of a scanning probe microscope head of the present invention which is comprised of a flexible shaft including an inner flexible tube and an outer flexible tube, fixtures for fixing both ends of the outer flexible tube, a displacement lead-in portion for displacing one end of the inner flexible tube relative to the outer flexible tube, a sample carrier portion for holding a sample and changing the direction of a plane of the sample by turning about a turn axis, and a displacement transmitting means connected to the other end of the inner flexible tube for transmitting the displacement led into the inner flexible tube by the displacement lead-in portion to the sample carrier portion in order to turn the sample carrier portion about the turn axis.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a sample stage of a scanning probe microscope head according to a first embodiment of the present invention;
FIG. 2 is a perspective view of a linear lead-in device used as a displacement lead-in portion;
FIG. 3 is a perspective view of a rotary lead-in device used as the displacement lead-in portion;
FIG. 4 is a perspective view of a linear displacement lead-out portion;
FIG. 5 is a perspective view of a rotary displacement lead-out portion;
FIG. 6 is a perspective view of a fixture;
FIGS. 7A to 7D are respectively top, front, side and rear views of a sample carrier portion;
FIGS. 8A to 8C are respectively top, front and side views showing the relationship between a turn base and a sample carrier, and FIG. 8D is a side view showing a state in which the turn base is turned at an angle of 90°;
FIG. 9 is a perspective view showing how to mount the sample carrier on the turn base;
FIG. 10 is a partly enlarged view showing the sample carrier mounted on the turn base;
FIGS. 11A to 11C are respectively top, front and side views showing the relationship between the sample carrier and a sample;
FIG. 12 is a perspective view of a ultra-high vacuum scanning tunneling microscope head using the sample stage in the first embodiment;
FIGS. 13A, 13B, 14A and 14B are views showing the relationship between a turn engaging rod and a catcher;
FIGS. 15 to 17 are views showing operations of the scanning tunneling microscope head shown in FIG. 12;
FIGS. 18A to 18C are respectively top, front and side views of a sample carrier portion according to a second embodiment of the present invention;
FIGS. 19A to 19C are respectively top, front and side views of a sample carrier portion according to a first variation of the second embodiment;
FIGS. 20A to 20C are respectively top, front and side views of a sample carrier portion according to a second variation of the second embodiment;
FIGS. 21A to 21C are respectively top, front and side views of a sample carrier portion according to a third variation of the second embodiment;
FIG. 22 is a perspective view of a sample stage according to a third embodiment;
FIGS. 23A, 23B, 24A, 24B, 25A and 25B are views showing a displacement transmission means in the third embodiment;
FIG. 26 is a perspective view of a sample stage according to a fourth embodiment;
FIG. 27 is a perspective view of a sample stage according to a variation of the fourth embodiment;
FIG. 28 is a perspective view of a conventional sample stage; and
FIG. 29A is a side view of another conventional sample stage in operation of a STM and FIG. 29B is a side view showing a state in which the direction of a sample plane of the sample stage shown in FIG. 29A is changed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention will now be described with reference to the drawings.
First Embodiment
FIG. 1 illustrates a sample stage of a scanning probe microscope head according to a first embodiment. Referring to FIG. 1, a flexible shaft 200 consists of an inner flexible tube 210 and an outer flexible tube 220, and both ends of the outer flexible tube 220 are fixed by fixtures 310 and 320. A displacement lead-in portion 400 and a displacement lead-out portion 500 are respectively connected to one end and the other end of the inner flexible tube 210. A sample carrier portion 700 is connected to the displacement lead-out portion 500 through a coupling portion 600. The displacement lead-out portion 500 and the coupling portion 600 constitute a displacement transmitting means of the present invention.
The flexible shaft 200 has a structure in which the inner flexible tube 210 is inserted in the outer flexible tube 220, and transmits the rotational or linear motion through the displacement of the inner flexible tube 210 relative to the outer flexible tube 220. An ultra-high vacuum bellows linear or rotary lead-in device 410 or 420 shown in FIG. 2 or 3 is used as the displacement lead-in portion 400.
As the displacement lead-out portion 500 and the coupling portion 600, for example, a linear displacement lead-out device 510 and a linear coupling portion 610 shown in FIG. 4 can be used. The linear displacement lead-out device 510 has a catcher 511 having a square hole at an end thereof, and the linear coupling portion 610 has an engaging rod 611 to be fitted in the square hole of the catcher 511. The catcher 511 is inclined from the horizontal plane at an angle α almost equal to 45°, and the square hole thereof has such dimensions as to fit the engaging rod 611 therein even if the linear coupling portion 610 is turned at an angle of 90°. The catcher 511 and the engaging rod 611 are engaged with each other in correlation to the movement of the linear displacement lead-in portion 510, thereby converting the linear motion to the rotational motion. The mechanical engagement of the catcher 511 and the engaging rod 611 can be released by linearly moving the linear displacement lead-in portion 510 in the reverse direction and forming a void between the catcher 511 and the engaging rod 611.
As the displacement lead-out portion 500 and the coupling portion 600, for example, a rotary displacement lead-out device 520 and a rotary coupling portion 620 shown in FIG. 5 may be used. The rotary displacement lead-out device 520 is connected to the end of the inner flexible tube 210 and ends with two pins 521 embedded therein at the same distance from a center shaft of the inner flexible tube 210. The rotary coupling portion 620 is provided with a pull 621 to be inserted between the pins 521 at sufficient intervals. The rotation of the rotary displacement lead-in portion 520 is transmitted to the rotary coupling portion 600 through the pins 521 and the pull 621 as it is to turn the rotary coupling portion 600. The mechanical engagement of the pins 521 and the pull 621 can be released by turning the rotary displacement lead-out device 520 in the opposite direction and forming a void between the pins 521 and the pull 621.
As shown in FIG. 6, the fixture 310 fixes the end of the outer flexible tube 220 between a pair of fixing members 311 and 312, which have respective slots formed on opposed planes thereof, by screws 313, and the fixing members 311 and 312 are fixed to a fixing plane 314 by screws or the like. The linear lead-in device 410 and the end of the inner flexible tube 210 are connected through a connector 411 and screws 412. The fixture 320 on the side of the displacement lead-out portion 500 has the same structure as that of the fixture 310 shown in FIG. 6.
FIGS. 7A to 7D are respectively top, front, side and rear views of the sample carrier portion 700 using the linear displacement lead-out device 510 shown in FIG. 4. A turn base fitting 720 is screwed to a frame 710, and a turn base 740 having a turn shaft 730 jointly with the turn base fitting 720 as a bearing is mounted. A sample carrier 750 for holding a sample 900 is laid on the turn base 740, and the turn base fitting 720 is provided with a turn base stopper 760 for restricting the excessive movement of the turn base 740. Furthermore, turn shaft fixtures 731 and 732 are mounted on the turn shaft 730 to prevent the turn shaft 730 from separating from the turn base fitting 720 and the turn base 740. A turn engaging rod 733 as a part of the linear coupling portion 610 is screwed into the turn shaft fixture 731.
FIGS. 8A to 8C are respectively top, front and side views showing the relationship between the turn base 740 and the sample carrier 750. FIG. 8D is a side view showing a state in which the turn base 740 is turned at an angle of 90°.
FIG. 9 is a perspective view explaining how to mount the sample carrier 750 to the turn base 740. A sample carrier insertion pin 741 having a neck slot 742 is screwed into the turn base 740 and a fitting hole 752 and a sample exchange female screw 753 are formed on the sample carrier 750. Furthermore, a U-shaped insertion pin presser spring 751 is inserted in a hole formed in the sample carrier 750 to be in contact with the inner surfaces of the fitting hole 752 and the sample exchange female screw 753. When the sample carrier 750 is moved toward the turn base 740 along an axis X--X, the insertion pin presser spring 751 is, as shown in FIG. 10, fitted in the neck slot 742 of the insertion pin 741, thereby connecting the turn base 740 and the sample carrier 750.
As shown in FIGS. 11A to 11C, the sample 900 is sandwiched between the sample carrier 750 and spring portions on both sides of a notch portion of a sample presser bar flat spring 901 fixed by bar flat spring screws 902, and pressed against the sample carrier 750 by elastic force of the spring portions.
FIG. 12 illustrates an ultra-high vacuum scanning tunneling microscope head using the sample stage of the first embodiment. In this head, the linear lead-in portion 410 shown in FIG. 2 as the displacement lead-in portion 400 of the sample stage and the linear displacement lead-out device 510 and the linear coupling portion 610 shown in FIG. 4 as the displacement lead-out portion 500 and the coupling portion 600 are used. The operation of the first embodiment will be described with reference to FIG. 12.
A sample stage flange 810 as a part of a vacuum vessel is provided with the linear lead-in device 410, a clamp linear lead-in device 820, a coarse drive rotary lead-in device 830, a coarse drive linear lead-in device 840 and a sight glass 850 on the air side, and a hanging bar 860 and an arm 870 on the vacuum side. The clamp linear lead-in device 820 has a clamp rod 821, whose leading end is conic, on the vacuum side thereof, and the hanging bar 860 has a clamp plate 861 with a conic projection at the end thereof and vibration-isolating hanging springs 862. A probe portion 880 constituted by the sample carrier portion 700, a probe 881, a scanning piezoelectric device 882 and a piezoelectric device attachment plate 883 is laid on a top plate 863 hung by the hanging springs 862. The flexible shaft 200, the fixtures 310 and 320, the linear displacement lead-out device 510 and a supporter 871 for holding the flexible shaft 200 to prevent the flexible shaft 200 from being twisted and bent by its own weight thereof are mounted to the arm 870. The linear lead-in device connector 411 is disposed between the linear lead-in device 410 and the fixture 310.
First, the fitting and fixing position of the linear displacement lead-out device 510 and the linear coupling portion 610 is adjusted and set. When the leading end of the clamp rod 821 is pressed against one side of the top plate 863 hung by the springs 862 by the clamp linear lead-in device 820, the sample carrier portion 700 and the probe portion 800 mounted on the top plate 863 are pushed together with the top plate 863. When one end of the top plate 863 is brought into contact with the conic projection of the clamp plate 861, the motion of the clamp linear lead-in device 820 is stopped, and the sample carrier portion 700 and the probe portion 800 are brought into a clamp state together with the top plate 863 hung by the hanging springs 862, thereby stopping the swing of the top plate 863 caused by the hanging springs 862.
By pulling the inner flexible tube 210 by the linear lead-in device 410 in such clamp state, as shown in FIG. 12, the direction of the turn base 740 is changed so that the sample 900 faces the probe 881. The mount positions of the hanging springs 862, the clamp rod 821 and the clamp plate 861 and the mount angle of the turn shaft engaging rod 733 to the turn shaft fixture 731 are adjusted and set so that the turn engaging rod 733 is positioned as close as possible to and without contact with one inner end 511a of the square hole of the catcher 511 as shown in FIGS. 13A and 13B in both the clamp and non-clamp states.
Subsequently, it is ascertained that, when the inner flexible tube 210 is extended by moving the linear lead-in device 410 in the opposite direction in the clamp state and the turn shaft fixture 731 is turned while making the turn engaging rod 733 in contact with the other inner end 511b of the square hole of the catcher 511 as shown in FIGS. 14A and 14B, the turn base 740 is gradually turned together with the turn shaft fixture 731 by a couple resulting from the own weight thereof and finally stopped by the turn base stopper 760. Furthermore, it is ascertained that, when the turn shaft fixture 731 is reversely turned by pulling the inner flexible tube 210 again, the turn base 740 is reversely turned by the couple resulting from the own weight thereof as shown in FIGS. 13A and 13B and finally stopped by the contact with the frame 710 and that the turn engaging rod 733 is positioned in the square hole without contact with the catcher 511 in the non-clamp state.
After such adjustment and setting, when the inner flexible tube 210 is advanced by the linear lead-in device 410, the sample 900 is turned together with the turn base 740 to point upward as shown in FIG. 15. By radiating, for example, an infrared ray 910 onto the plane of the sample 900 in this state, the sample 900 can be heated and cleaned. Furthermore, the sample 900 can be exchanged with another by screwing a sample exchange male screw 921 formed at the leading end of a sample exchange rod 920 to the sample exchange female screw 753 of the sample carrier 750 and inserting and extracting the sample carrier 750 into and from the turn base 740 as shown in FIG. 16. On the other hand, when the inner flexible tube 210 is retracted by the linear lead-in device 410, the sample 900 is turned toward the probe 881 together with the turn base 740 as shown in FIG. 17. In this state, the scanning tunneling microscope can work.
Materials and dimensions of the components of the sample stage in the first embodiment will be described in detail. Both the outer flexible tube 220 and the inner flexible tube 210 constituting the flexible shaft 200 are shaped like a spring, and the material thereof is a C hard steel wire (JIS-G3521) which has large tensile strength and torsional stress and high abrasion resistance, or a stainless steel wire for a vacuum. The inner flexible tube 210 is 0.3 mm in wire diameter, 1.0 mm in outer spring diameter, 0 mm in spacing between turns and 20 mm in bend radius, and the outer flexible tube 220 is 0.6 mm in wire diameter, 2.5 mm in outer spring diameter and 0.3 mm in winding pitch. The bend radius of the flexible shaft 200 is 20 mm. If the bend radius may be larger, the outer flexible tube 220 is made of a coil of a flat steel wire so that the inner flexible tube 210 can smoothly slide inside the outer flexible tube 220. In order to further promote the sliding, a perfluorinated grease, FOMBLIN, whose vapor pressure is less than 10 -9 Pa may be interposed as a lubricant between the inner flexible tube 210 and the outer flexible tube 220.
The fixing members 311 and 312 and the screws 313 constituting the fixtures 310 and 320, the linear lead-in portion connector 411 and the screws 412 are made of stainless steel (SUS-304 and JIS-G-4303, referred to as SUS hereinafter).
The linear movement of the linear lead-in device 410 used as the displacement lead-in portion 400 is 20 mm and the rotation angle of the rotary lead-in device 420 is not limited. The linear lead-in device 410 and the rotary lead-in device 420 each have a drive shaft diameter of 6 mm and a connecting flange diameter of φ 34ICF, and either of these lead-in devices is attached to the sample stage flange 810 of φ 203ICF shown in FIG. 12.
The linear displacement lead-out device 510 or the rotary displacement lead-out device 520 as the displacement. lead-out portion 500 and the linear coupling portion 610 or the rotary coupling portion 620 as the coupling portion 600 are made of SUS.
The square hole of the catcher 511 used in the displacement lead-out device 510 shown in FIG. 12 is 5 mm in width and 9 mm in length, and the turn engaging rod 733, made of steel wire (piano wire of JIS-G3522, referred to as piano wire) having a diameter of 1 mm, is fitted therein. The turn engaging rod 733 is fixed in a hole formed on the side of the turn shaft fixture 731 in an interference fit.
The frame 710 as a component of the sample carrier portion 700 is made of SUS, and has a width of 60 mm, a height of 50 mm and a depth of 8 mm. A square slot having a width of 10+0.05 mm, a height of 13 mm and a depth of 8 mm is formed in the center of the top of the frame 710 to insert and extract the sample carrier 750 therein and therefrom. A void is formed between the square slot of the frame 710 and the sample carrier 750 by making the width of the sample carrier 750 smaller than that of the square slot so that the turn can be kept even if thermal expansion is caused by the rise of temperature in degassing.
The turn base fixture 720 made of SUS with outward dimensions of 205 mm in width, 14 mm in height and 6 mm in depth is U-shaped with a square slot having a width of 10+0.05 mm, a height of 8 mm and a depth of 6 mm, and is fixed to the frame 710 by screws. The turn shaft 730 made of piano wire having a diameter of 1.5 mm is inserted in holes respectively formed in the turn base fixture 720 and the turn base 740 made of SUS.
The sample carrier 750 is made of SUS and shaped in a rectangular parallelepiped of 10-0.05 mm in width, 10 mm in height and 8 mm in depth. The radius of curvature of the neck slot 742 of the sample carrier insertion pin 741 made of SUS, whose leading end is curved in a radius of curvature of 1.5 mm, is 0.3 mm and the U-shaped insertion pin presser spring 751 made of piano wire having a diameter of 0.2 mm is fitted in the neck slot 742. The sample presser bar flat spring 901 is made of a phosphor bronze plate (JIS-H3110) having a thickness of 0.2 mm and fixed onto the sample carrier 750 by four screws (M1.2). The turn base stopper 760 and the turn shaft fixtures 731 and 732 are each made of SUS. The turn shaft fixtures 731 and 732 each have a diameter of 5.8 mm, and the turn shaft 730 is fixed thereto by screws (M1.2).
The total weight of a rotary body constituted by the sample carrier 750, the sampler presser bar flat spring 901, the turn base 740, the sample carrier insertion pin 741 and the insertion pin presser spring 751 is approximately 12 g. The turn base 740 having an average surface roughness Ra (JIS-B0601) of less than 0.10a is laid on the plane of the square slot of the frame 710 having the same average surface roughness, thereby functioning as an STM.
Second Embodiment
FIGS. 18A to 18C are respectively top, front and side views showing a sample carrier portion in a sample stage according to a second embodiment of the present invention. A square slot in which the turn base 740 and the sample carrier 750 are housed is formed on the top of the frame 710, and a pair of slots 711a extending from the front side to the rear side of the frame 710 are formed on planes of the square slot. Ends of sample carrier presser bar flat springs 711 as sample carrier presser members in the present invention are respectively fixed in the slots 711a by screws.
When the sample carrier 750 is turned and inserted in the square slot of the frame 710, both sides thereof are pressed by the elastic forces of the sample carrier presser bar flat springs 711 mounted in the slots 711a. Therefore, the change of displacement of the turn shaft 730 in the axial direction is restricted, and a rotary body constituted by the sample carrier 750, the sample presser bar flat spring 901, the turn base 740, the sample carrier insertion pin 741 and the insertion pin presser spring 751 can perform a reliable STM operation.
FIGS. 19A to 19C illustrates a variation of the sample carrier portion according to the second embodiment. In the variation shown in FIGS. 19A to 19C, a pair of slots 712a extending downward from the top of the frame 710 are formed in the square slot of the frame 710, and ends of sample carrier presser bar flat springs 712 each made of plywood are respectively screwed in the slots 712a. Furthermore, metallic balls 713 are put between the other ends of the sample carrier presser bar flat springs 712 and both sides of the sample carrier 750. This serves to smoothly turn and insert the sample carrier 750 in the square slot of the frame 710, thereby achieving a reliable STM operation as described above.
In another variation shown in FIGS. 20A to 20C, pits 714a are further formed to pierce the square slot and the slots 712a in the variation shown in FIGS. 19A to 19C, and compression springs 714 are mounted in the pits 714a. The metallic balls 713 held by the sample carrier presser bar flat springs 712 are urged toward the sample carrier 750 by the compression springs 714. Therefore, the change of position of the turn shaft 730 in the axial direction is restricted and the rotary body including the sample carrier 750 can perform a reliable STM operation.
In still another variation shown in FIGS. 21a to 21C, magnets 715 are respectively fixed by an adhesive in the slots 711a formed in the square slot to extend from the front to the rear. Since the magnets 715 in the slots 711a attract both sides of the sample carrier 750, a reliable STM operation is achieved.
Materials and dimensions of the components of the sample carrier portion 700 in the second embodiment will now be described in detail. The slots 711 a and 712 are each 3.5 mm in width and 3 mm in depth, and the pits 714a are each 2.5 mm in diameter and 8 mm in depth. The sample carrier presser bar flat springs 711 are each made of a phosphor bronze plate (JIS-H3110) having a thickness of 0.1 mm and a width of 3 mm. Each of the sample carrier presser bar flat springs 712 is made of a two-ply plate of the same phosphor bronze as mentioned above, and has a hole of 1.8 mm in diameter in a portion for holding the metallic ball 713. The metallic balls 713 each are made of a rigid ball (JIS-B1501) for a ball bearing having a diameter of 2 mm. Each of the compression springs 714 is a coil spring of 0.2 mm in wire diameter, 2.0 mm in outer diameter, 16 g/mm in spring constant and 12 mm in free length. As the magnets 715, a rare earth magnet, such as a neodymium (Nd-Fe-B) magnet or a samarium cobalt (Sm-Co) magnet, having a diameter of 2mm, a thickness of 3 mm and a magnetic force of 2500 to 3200G, is used.
A ball made of a precious stone, such as ruby, may be used instead of the metallic balls 713. Furthermore, the metallic balls 713 made of bearing rigid balls may be given the same effect as that of the magnets 715 in the variation shown in FIGS. 21A to 21C by being magnetized.
If the metallic balls 713 in the variation shown in FIGS. 21A to 21C are magnetized, the frame 710 and the sample carrier 750 are made of highly permeable stainless steel (SUS430, JIS-G4303), or highly permeable Invar (Fe: 64%, Ni: 36%) or Super Invar (Fe: 63%, Ni: 32%, Co: 5%) having a small coefficient of thermal expansion, and a magnet circuit is closed when the sample carrier 750 is turned and inserted in the square slot of the frame 710.
As the adhesive for fixing the magnets 715 in the slots 711a, for example, a curing agent consisting of thixotropic epoxy resin and aromatic amine or a vacuum leak inhibitor, Torr-Seal, having a low vapor pressure less than 10 -7 Pa is used.
Third Embodiment
FIG. 22 illustrates a sample stage according to a third embodiment of the present invention. Referring to FIG. 22, numerals 320a, 320b, 510a and 510b respectively denote a fixture contact portion where the fixture 320 is in contact with the linear displacement lead-out device 510, a guide portion, a linear displacement lead-out contact portion where the linear displacement lead-out device 510 is in contact with the turn shaft fixture 731, and a guide contact portion. The fixture 731 and the linear displacement lead-out device 510 are so shaped that the catcher 511 is put in a horizontal position and the turn engaging rod 733 escapes from the square hole of the catcher 511 when the inner flexible tube 210 of the flexible shaft 200 is pulled.
The operation of the sample stage in the third embodiment will now be described. When the inner flexible tube 210 is advanced, as shown in FIGS. 23A and 23B, the turn shaft fixture 731 is turned while the turn engaging rod 733 is kept in contact with the inner end 511b of the square hole of the catcher 511. To the contrary, when the inner flexible tube 210 is pulled, as shown in FIGS. 24A and 24B, the turn shaft fixture 731 is reversely turned while the turn engaging rod 733 is kept in contact with the other inner end 511a of the square hole of the catcher 511. During the reverse turn, the guide contact portion 510b of the linear displacement lead-out device 510 runs onto the guide portion 320b of the fixture 320, and the inner end 571a of the square hole of the catcher 511 is lifted up. When the inner flexible tube 210 is further pulled, as shown in FIGS. 25A and 25B, the linear displacement lead-out device 510 is brought into planar contact with the fixture contact portion 320a, the catcher 511 is put in a horizontal position, and the turn engaging rod 733 completely escapes from the square hole of the catcher 511.
According to the third embodiment, since the turn engaging rod 733 completely escapes from the square hole of the catcher 511, it is not in contact with the square hole of the catcher 511 even if vibration is applied to the whole STM in operation. Therefore, it is possible to continue stable operation for a long time.
Fourth Embodiment
FIG. 26 illustrates a sample stage according to a fourth embodiment of the present invention. In the fourth embodiment, the displacement led in the inner flexible shaft 210 of the flexible shaft 200 is transmitted to the sample carrier portion 700 through a gear transmission mechanism. Referring to FIG. 26, a rack 512 is mounted in the linear displacement lead-out device 510, and a pinion 612 is mounted in the linear coupling portion 610. The rack 512 and the pinion 612 form a rack and pinion structure. The advance and retraction of the linear displacement lead-out device 510 are converted into the rotation of the pinion 612 through the rack 512, thereby turning the sample 900 in the sample carrier portion 700.
As shown in FIG. 27, the rotation led out by the rotary displacement lead-out device 520 may be transmitted to the sample carrier portion 700 through a gear transmission mechanism. Referring to FIG. 27, a main driving gear 522 formed in the rotary displacement lead-out device 520 and a driven gear 622 formed in the rotary coupling portion 620 form a spur gear transmission structure. The rotation of the main driving gear 522 in the rotary displacement lead-out device 520 is transmitted to the driven gear 622 to turn the sample 900 in the sample carrier portion 700.
According to the fourth embodiment, since the power is transmitted by using gears, the displacement led in the inner flexible tube 210 of the flexible shaft 200 is transmitted to the sample carrier portion 700 with reliability.
Though the direction of the plane of the sample 900 is changed between the horizontal direction and the vertical direction in the above embodiments, it may be arbitrarily changed by changing the axial mount direction of the turn shaft 730 in the sample carrier portion 700.
Furthermore, though the sample stage of the present invention is applied to an STM in the above embodiments, the present invention is not limited to the embodiments and may be applied as a sample stage of, for example, an atomic force microscope.
|
A sample stage of a scanning probe microscope head is capable of changing the direction of a sample plane stably over a wide range in a simple operation. Fixtures fix both ends of an outer flexible tube of a flexible shaft. A displacement lead-in portion displaces one end of an inner flexible tube of the flexible shaft relative to the outer flexible tube, and a displacement lead-out portion and a coupling portion transmit the displacement led in the inner flexible tube of the flexible shaft to a sample carrier portion to turn the sample carrier portion about a turn axis, thereby getting a sample plane to change direction.
| 8
|
FIELD OF THE INVENTION
The invention relates generally to image processing and more specifically to a technique for registering images, typically for further processing.
BACKGROUND OF THE INVENTION
It is frequently desirable when copying documents to have the output image content aligned in a particular way on the page, for example to provide room for binding or to center the image content on the page. Some copiers (such as the Xerox 9700) have an user-selectable "margin shift" feature that allows offsetting the image content by either a fixed or variable amount in which the user can select (via a dial) some particular distance, and then that same distance will be applied to every page. However, this assumes that all of the originals being copied are similarly registered to work properly. Other copiers (such as the Canon CLC-500) offer an automatic center shift feature. However, this works by detecting a white border around the page being copied and thus moves the entire page, rather than the image content on the page. Both of these examples are instances of absolute registration, i.e. image displacement to a fixed, known position. Neither of the example solutions is capable of dealing with a related problem, relative registration. In relative registration, it is desired to find the best match of a given image content to some reference image content, without any a priori information as to the position of the reference image content.
A simple, relatively inexpensive, and accurate approach to register images in such printing systems has been a goal in the design, manufacture and use of printers. The need to provide accurate and inexpensive registration has become more acute, as the demand for high quality, relatively inexpensive images has increased.
Various techniques for registering images have hereinbefore been devised as illustrated by the following disclosures, which may be relevant to certain aspects of the present invention:
U.S. Pat. No. 5,129,014
Patentee: Bloomberg
Issued: Jul. 7, 1992
U.S. Pat. No. 5,086,482
Patentee: Kumagai
Issued: Feb. 4, 1992
U.S. Pat. No. 5,129,014 discloses a technique for rapidly and efficiently registering binary images, contemplates incorporating one or more reference features, referred to as fiducials, into the binary image at a known displacement from a feature of interest in the image, subjecting the image to an operation (typically a morphological operation and possibly a thresholded reduction) that projects out the fiducial(s), determining the position of the fiducial(s), and thereby determining the position of the feature of interest. The fiducial(s) must have at least one characteristic that is absent from the remaining or at least from neighboring) portions of the image. In one set of embodiments, each fiducial includes horizontal and vertical line segments that are longer than any line segments expected to be found in the binary image. Projecting out the fiducial entails erosions using hit-miss structuring elements. In another embodiment, each fiducial is a small finely textured region.
U.S. Pat. No. 5,086,482 discloses an image processing method for generating a convex hull of a configuration in a digital image. Top points of the convex hull are selected. A reference line connecting the top points is defined. For each area between two adjacent top points, continuous pixels are selected from one top point toward the other so that each pixel is the nearest to the reference line as well as between the reference line and a contour of the configuration. Distances from pixels to the reference line are calculated from chain codes.
SUMMARY OF THE INVENTION
In accordance with the invention there is provided a method of processing one or more pages in a printing system comprising the steps of scanning a first page having first image content, and generating a boundary defining a positional relationship between the first image content and the first page. A second image content is outputted to a second page with the position of the second image content on the second page being a function of the boundary.
Pursuant to another aspect of the invention, there is provided a method for automatically registering a document having a plurality of pages with image content to be printed by an electronic reprographic system, the method comprises the steps of scanning a first page having original image content with a scanner, and generating an electronic representation of the page with the original image content being enclosed by a designated area. A second page having original image content is scanned with the scanner and the original image content of the second page is registered in the designated area.
These and other aspects of the invention will become apparent from the following description used to illustrate a preferred embodiment of the invention read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of an image scanning and processing system incorporating the present invention;
FIG. 2A illustrates a text document image to be processed by the present invention;
FIG. 2B-2D illustrates a first mode of processing the text document image by the present invention;
FIG. 3 illustrates a second mode of processing the text document image of FIG. 2D by the present invention;
FIG. 4 illustrates a third mode of processing the text document images of FIG. 2D and FIG. 3 by the present invention;
FIG. 5 is a block diagram of the processor of the present invention.
While the present invention is described primarily in connection with a preferred embodiment thereof, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present discussion deals with binary images. In this context, the term "image" refers to a representation of a two-dimensional data structure composed of pixels. A binary image is an image where a given pixel is either "ON" or "OFF." Binary images are manipulated according to a number of operations wherein one or more source images are mapped onto a destination image. The results of such operations are generally referred to as images. The image that is the starting point for processing will sometimes be referred to as the original image.
Pixels are defined to be ON if they are black and OFF if they are white. Also, Pixels (sometimes referred as image signals) are signals representing optical density of the image of a discrete areas in a document. It should be noted that the designation of black as ON and white as OFF reflects the fact that most documents of interest have a black foreground and a white background. While the techniques of the present invention could be applied to negative images as well, the discussion will be in terms of black on white.
"Image content" is an area of a document containing "text" or "line graphics".
A "solid region" of an image refers to a region extending many pixels in both dimensions within which substantially all the pixels are ON.
A "textured region" of an image refers to a region that contains a relatively fine-grained pattern. Examples of textured regions are half-toned or stippled regions.
"Text" refers to portions of a document or image containing letters, numbers, or other symbols including non-alphabetic linguistic characters.
"Line graphics" refers to portions of a document or image composed of graphs, figures, or drawings other than text, generally composed of horizontal, vertical, and skewed lines having a substantial run length as compared to text. Graphics could range from horizontal and vertical lines in an organization chart to more complicated horizontal, vertical, and skewed lines in engineering drawings.
AND, OR, and XOR are logical operations carried out between two images on a pixel-by-pixel basis.
NOT is a logical operation carried out on a single image on a pixel-by-pixel basis.
"Expansion" is a scale operation characterized by a SCALE factor N, wherein each pixel in a source image becomes an NXN square of pixels, all having the same value as the original pixel.
"Reduction" is a scale operation characterized by a SCALE factor N and a threshold LEVEL M. Reduction with SCALE=N entails dividing the source image into NXN squares of pixels, mapping each such square in the source image to a single pixel on the destination image. The value for the pixel in the destination image is determined by the threshold LEVEL M, which is a number between 1 and N sup 2. If the number of ON pixels in the pixel square is greater or equal to M, the destination pixel is ON, otherwise it is OFF.
A number of morphological operations map a source image onto an equally sized destination image according to a rule defined by a pixel pattern called a structuring element (SE). The SE is defined by a center location and a number of pixel locations, each having a defined value (ON or OFF). Other pixel positions, referred to as "don't care", are ignored. The pixels defining the SE do not have to be adjacent each other. The center location need not be at the geometrical center of the pattern; indeed it need not even be inside the pattern.
A "solid" SE refers to an SE having a periphery within which all pixels are ON. For example, a solid 2X2 SE is a 2X2 square of ON pixels. A solid SE need not be rectangular.
"Erosion" is a morphological operation wherein a given pixel in the destination image is turned ON if and only if the result of superimposing the SE center on the corresponding pixel location in the source image results in a match between all ON and OFF pixels in the SE and the underlying pixels in the source image.
The various operations defined above are sometimes referred to in noun, adjective, and verb forms. For example, references to erosion (noun form) may be in terms of eroding the image or the image being eroded (verb forms) or the image being subjected to a erosion operation (adjective form). No difference in meaning is intended.
FIG. 1 is a block diagram of an image analysis system 1 within which the present invention may be embodied. The basic operation of system 1 is to extract or eliminate certain characteristic portions of document 2. To this end, the system includes a scanner 3 which digitizes the document on a pixel basis, and provides a resultant data structure, typically referred to as an image. Depending on the application, the scanner may provide a binary image (a single bit per pixel) or a gray scale image (a plurality of bits per pixel). The image contains the raw content of the document, to the precision of the resolution of the scanner. The image may be sent to a memory 4 or stored as a file in a file storage unit 5, which may be a disk or other mass storage device.
A processor 6 controls the data flow and performs the image processing, including for example, the automatic document registration processing of the present invention. Processor 6 may be a general purpose computer, a special purpose computer optimized for image processing operations, or a combination of a general purpose computer and auxiliary special purpose hardware. If a file storage unit is used, the image is transferred to memory 4 prior to processing. Memory 4 may also be used to store intermediate data structures and possibly a final processed data structure.
The result of the image processing, of which the present invention forms a part, can be a derived image, numerical data (such as coordinates of salient features of the image) or a combination. This information may be communicated to application specific hardware 8, which may be a printer or display, or may be written back to file storage unit 5.
The foregoing description should be sufficient to illustrate the general operation of an image analysis system.
The features of the present invention will now be discussed in greater detail with reference to FIG. 5 of the drawings.
FIG. 5 is a block diagram of processor 6, at step 100 the skew of the original image content is determined. Lines of the bitmap are scanned and a variance in the number of ON pixels as a function of skew angle is calculated. Skew of a document image occurs when the variance is a maximum. Efficient means for calculating skew of a document is known for example, U.S. Pat. No. 5,187,753 to Bloomberg et al., assigned to Xerox Corporation and issued on Feb. 16, 1993, is hereby incorporated herein by reference thereto. Once the skew has been identified, the original image is deskewed. Skew correction is achieved by rotating the image. Efficient means for rotating an image using bitblt (i.e. raster operations) are known and discussed in for example, Paeth, "A Fast Algorithm for Fast Raster Rotation," Vision Interface '86, Vancouver B.C., May 1986, pg. 77-81, which is incorporated by reference herein.
At step 102, the boundary enclosing the original image content is determined, (referred as generating a quadratic convex hull). The boundary is determined by iteratively ORing individual pixels of the original image with the adjacent pixel, laterally across the page from left to right as shown in FIGS. 2A, 2B and 2C producing the result in FIG. 2D. Next, the same process is carried out vertically starting with the image in FIG. 2D as input producing the result in FIG. 3. Next, the quadratic convex hull is determined by ANDing the laterally and vertically ORed images producing the result in FIG. 4. Note that since the final result contains more than one solid region, it is not truly a hull in the strict sense.
At step 104, the coordinates of the corners of the hull are located, for example by raster scanning from left to right and from top to bottom the hull produced in step 102 until a non-zero pixel is encountered.
Once the corners of the hull are located at step 104, a second and subsequent documents are scanned and processed (i.e.. deskewed) and are aligned within the hull at step 106. For example, as describe so far, in a set of n images, the first scanned document is taken to be the original image and all subsequent images are aligned to it. In this case, the position of the first image is "not" changed. Alternatively, in a set of n images, all of the image locations can be changed, and if desired registered to a fixed location. The alignment is accomplished by determining the amount of adjustment necessary to shift the hull to a desired location, and then applying an equivalent shift to all pixels in the original image and subsequent images. This location may either be selected by the user in some manner (such as via dials, mouse, light pen, or other similar device), or preset to some known value by the machine (such as "upper-left corner" or "center")
At step 108 the original image and subsequent images are registered in relation to each other. For example if absolute registration was desired. The following function is employed, the input bit stream of the image in FIG. 2D and the first scan line with non-zero pixels is monitored and the lowest numbered non-zero pixel over all scan-lines is registered with the top and left margins respectively. It has been found that this method maybe susceptible to single-pixel image noise. In cases where this occurs, a morphological erosion can be performed on the image to eliminate single isolated pixel before determining the boundary (i.e. hull).
If relative registration is desired, one must select either local fit or global fit. Global fit is defined as positioning the image to be registered in such a way that it maximally overlaps the boundary of the reference image. Local fit is more restrictive. It is defined as positioning the image to be registered in such a way that it maximally over laps the reference image itself. In the present invention for global fit, the "input image" is the quadratic convex hull computed in FIG. 2D, while for local fit, the input image is the actual scanned-in image data (FIG. 2A). Basically, global fit is the maximum overlap of the outlines of the two images (the reference image and the incoming data image to be registered), whereas local fit is the maximum overlap of the actual image features, even if that results in a less-than-ideal overlap of the boundaries. For some images, both processes might yield the same result. However, both are computed using the same function:
1. The input image is logically AND'ed with the reference image (or its boundary) and the resulting number of pixels is counted.
2. The input image is displace by one pixel horizontally and step 1 is repeated. If the new pixel count is greater than the previous one, the current x-location is saved
3. Step 2 is repeated across the width of the page.
4. The input image is then positioned at the location that yielded the highest pixel count and step 1-3 are repeated vertically. The resulting y-location will yield the position of best registration for the input image.
It should be appreciated that relative registration can be placed under user control by providing an appropriate interface, such as a CRT and mouse. The user can sweep out a region at some place in the image to be used to control registration. For example, it might be desired to register all pages specifically to the location of a chapter heading. The input image would then be moved about the page looking for the best match within the user-defined region with the system providing realtime feedback as to how desirable the match is as at any given time.
It should be evident that overlap of image data of the second and subsequent documents which are positioned within the boundary could be improved if desired by reducing or expanding image pixels. This could be particularly desirable for registering line graphics documents with each other or with text documents.
It is, therefore, apparent that there has been provided a method for registering images in accordance with the present invention, that fully satisfies the aims and advantages hereinbefore set forth. While this invention has been described in conjunction with a specific embodiment thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.
|
A method for automatically registering documents being copied on an electronic reprographic copier. The registration of the document is based on the actual image content being copied, not the sheet it is on. A first document having original image content is scanned. The original image is processed. A boundary enclosing the original image content of the first document is identified. The boundary is identified by computing a quadratic convex hull of the original image. A second and subsequent documents having image content are scanned and processed. The image content of the second and subsequent documents are positioned within the boundary according to one of the following classes of registration: absolute registration, global fit relative registration or local fit relative registration.
| 7
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. application Ser. No. 14/486,040 filed Sep. 15, 2014 which is a divisional application of U.S. application Ser. No. 14/002,164 filed Aug. 29, 2013 now U.S Pat. No. 8,865,754 issued Oct. 21, 2014, which was filed under 35 U.S.C. 371 and is a U.S. National Stage application of PCT/US2012/027222 filed Mar. 1, 2012, and claims priority to U.S. Provisional Application No. 61/448,935, filed Mar. 3, 2011, each entitled “Compounds for the Treatment of Neurodegenerative Diseases”, the contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] Provided herein are compounds, pharmaceutical compositions, and methods for the treatment of neurodegenerative diseases such as Parkinson's disease and various tauopathies.
BACKGROUND OF INVENTION
[0003] Parkinson's disease (PD) is a neurodegenerative human disorder characterized clinically by both motor (movement) and non-motor behavioral dysfunction, and histopathologically by the formation, deposition, accumulation and/or persistence of abnormal fibrillar protein deposits and/or aggregates. This accumulation of cytoplasmic Lewy bodies consisting of fibrils/aggregates of α-synuclein/NAC (non-Aβ component) is believed important in the pathogenesis of PD. Lewy bodies occur mostly in the substantia nigra and locus ceruleus sections of the brain stem and the olfactory bulb, but also, to a lesser extent, in other subcortical and cortical regions of the brain. Because of this specific localization in the brain, Lewy bodies interfere with the health and integrity of dopaminergic neuronal projections from the substantia nigra to the striatum, thus adversely affecting the ability to initiate, carry out and control voluntary movements. Lewy bodies present in these brain regions may also impact the production of acetylcholine and/or the balance between dopamine and acetylcholine in the brain, thus causing disruption in perception, thinking and behavior as well as other non-motor symptoms including loss of smell and sleep disorders.
[0004] Dementia with Lewy Bodies (DLB) is a progressive neurodegenerative disorder characterized by symptoms which display various degrees of manifestation. Such symptoms include progressive dementia, Parkinsonian movement difficulties, hallucinations, and increased sensitivity to neuroleptic drugs. As with Alzheimer's disease (AD), advanced age is considered to be a risk factor for DLB, with average onset typically between the ages of 50-85. Twenty percent of all dementia cases are caused by DLB and over 50% of PD patients develop Parkinson's Disease Dementia (PDD), a type of DLB. DLB may occur alone or in conjunction with other brain abnormalities, including those involved in AD and PD, as mentioned above. Currently, conclusive diagnosis of DLB is made during postmortem autopsy.
[0005] New agents or compounds able to bind and/or inhibit α-synuclein and/or NAC formation, deposition, accumulation and/or persistence, or disrupt pre-formed α-synuclein/NAC fibrils and/or aggregates (or portions thereof) are regarded as potential therapeutics for the treatment of Parkinson's and related synucleinopathies. Compounds which protect neurons from degeneration and damage associated with Parkinson's and related synucleinopathies could also prove useful as therapeutics.
Parkinson's Disease and Synucleinopathies
[0006] Parkinson's disease is a neurodegenerative disorder that is pathologically characterized by the presence of intracytoplasmic Lewy bodies (Lewy in Handbuch der Neurologie , M. Lewandowski, ed., Springer, Berlin, pp. 920-933, 1912; Pollanen et al., J. Neuropath. Exp. Neural. 52:183-191, 1993), the major components of which are filaments consisting of α-synuclein (Spillantini et al., Proc. Natl. Acad. Sci. USA 95:6469-6473, 1998; Arai et al., Neurosci. Lett. 259:83-86, 1999), a 140-amino acid protein (Ueda et al., Proc. Natl. Acad. Sci. USA 90:11282-11286, 1993). Three dominant mutations in α-synuclein causing increased tendency to aggregate and resulting in familial early onset Parkinson's disease have been described suggesting that Lewy bodies contribute mechanistically to the degeneration of neurons in Parkinson's disease and related disorders (Polymeropoulos et al., Science 276:2045-2047, 1997; Kruger et al., Nature Genet. 18:106-108, 1998; Zarranz et al., Ann. Neurol. 55:164-173, 2004). Recently, in vitro studies have demonstrated that recombinant α-synuclein can indeed form Lewy body-like fibrils (Conway et al., Nature Med. 4:1318-1320, 1998; Hashimoto et al., Brain Res. 799:301-306, 1998; Nahri et al., J. Biol. Chem. 274:9843-9846, 1999; Choi et al., FEBS Lett. 576:363-368, 2004). Most importantly, both the A53T and the E46K Parkinson's disease-linked α-synuclein mutations accelerate this fibril-forming aggregation process, demonstrating that such in vitro studies may have relevance for Parkinson's disease pathogenesis. Alpha-synuclein aggregation and fibril formation fulfills the criteria of a nucleation-dependent polymerization process (Wood et al., J. Biol. Chem. 274:19509-19512, 1999). Alpha-synuclein recombinant protein, and non-Aβ component (known as NAC), which is a 35-amino acid peptide fragment of α-synuclein, both have the ability to form fibrils and/or aggregates when incubated at 37° C., and are positive with stains such as Congo red (demonstrating a red/green birefringence when viewed under polarized light) and Thioflavin S (demonstrating positive fluorescence) (Hashimoto et al., Brain Res. 799:301-306, 1998; Ueda et al., Proc. Natl. Acad. Sci. USA 90:11282-11286, 1993).
[0007] Synucleins are a family of small, presynaptic neuronal proteins composed of α-, β-, and γ-synucleins, of which only α-synuclein aggregates have been associated with several neurological diseases (Ian et al., Clinical Neurosc. Res. 1:445-455, 2001; Trojanowski and Lee, Neurotoxicology 23:457-460, 2002). The role of synucleins (and in particular, α-synuclein) in the etiology of a number of neurodegenerative diseases has developed from several observations. Pathologically, synuclein was identified as a major component of Lewy bodies, the hallmark inclusions of Parkinson's disease, and a fragment thereof was isolated from amyloid plaques of a different neurological disease, Alzheimer's disease. Biochemically, recombinant α-synuclein was shown to form fibrils and/or aggregates that recapitulated the ultrastructural features of α-synuclein isolated from patients with dementia with Lewy bodies, Parkinson's disease and multiple system atrophy. Additionally, the identification of mutations within the α-synuclein gene, albeit in rare cases of familial Parkinson's disease, demonstrated an unequivocal link between synuclein pathology and neurodegenerative diseases. The common involvement of α-synuclein in a spectrum of diseases such as Parkinson's disease, dementia with Lewy bodies, multiple system atrophy and the Lewy body variant of Alzheimer's disease has led to the classification of these diseases under the umbrella term of “synucleinopathies”.
[0008] NAC is a 35 amino acid fragment of α-synuclein that has the ability to form fibrils and/or aggregates either in vitro or as observed in the brains of patients with Parkinson's disease. The NAC fragment of α-synuclein is a relatively important therapeutic target as this portion of α-synuclein is believed crucial for formation of Lewy bodies as observed in all patients with Parkinson's disease, synucleinopathies and related disorders.
[0009] Currently available therapeutics such as carbidopa/levodopa (Sinemet, Stalevo, Parcopa), dopamine agonists (Apokyn, Parlodel, Neupro, Mirapex, Requip), anticholinergics (Cogentin, Artane), MAO-B inhibitors (Eldepryl, Carbex, Zelapar, Azilect), COMT inhibitors (Comtan, Tasmar), and other medications like Symmetrel and Exelon aim to slow the loss of dopamine or improve just the symptoms of the patient.
[0010] Discovery and identification of new compounds or agents as potential therapeutics to arrest fibril and/or aggregate formation, deposition, accumulation and/or persistence of α-synuclein in Parkinson's disease or provide neuroprotection are desperately sought.
[0011] Parkinson's disease α-synuclein fibrils and/or aggregates consist of a predominantly 1-pleated sheet structure. Compounds of this invention have been shown to be effective in the inhibition of α-synuclein/NAC fibril formation and/or aggregates as well as in the disruption of pre-formed fibrils and/or aggregates, as shown from Examples provided herein. These compounds could serve as therapeutics for Parkinson's disease and other synucleinopathies.
[0012] Tau is a microtubule associated protein found primarily in neuronal axons. Tau hyperphosphorylation is a common characteristic of a number of dementing disorders collectively known as tauopathies, some of which have disctinct tau pathology combined with other brain pathologies. Tauopathies include Alzheimer's disease (AD), Pick's disease (PiD), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD) and familial frontotemporal dementia/Parkinsonism linked to chromosome 17 (FTDP-17), amyotrophic lateral sclerosis/Parkinsonism-dementia complex, argyrophilic grain dementia, dementia pugilistic, diffuse neurofibrillary tangles with calcification, progressive subcortical gliosis and tangle only dementia. (Spillantini, M G and Goedert M, 1998 Trends Neurosci. October 21(10):428-33). In AD, tau pathology is typically limited to the neurons while other tauopathies can pathologically exhibit both neuronal and glial tau deposition (Higuchi, M, et al., 2002. Neuropsychopharmacology: The Fifth Generation of Progress, Chapter 94: Tau protein and tauopathy).
[0013] It has recently been postulated that tau protein may link Parkinson's and Alzheimer's disease (Shulman, J. M. and DeJager, P. L. 2009 Nature Genetics 41(12):1261-1262). This study examined whether any genome wide association occurs between the two diseases and found that three genes and two new loci were linked to increased susceptibility.
[0014] Physiological phosphorylation of tau regulates the dynamics of the association of tau with tubulin, and thereby microtubule stability (Mazanetz. M. P. and Fischer, P. M. 2007. Nature Reviews 6:464-479). The stabilization of the microtubules in axons ensures that maintain their function for axonal transport, growth and branching (Bulic, B et al., 2009 Angew. Chem. Int. Ed. 48:2-15). Hyperphosphorylation and misfolding of the tau protein is thought to be the causative factor in abnormal intracellular aggregation leading ultimately to neuronal dysfunction. Protein aggregates have been found to be toxic to neurons.
[0015] Abnormal intraneuronal tau aggregation has three basic pathological manifestations; neurofibrillary tangles (NFT's), neuropil threads (NT's) and the argyrophilic dystrophic neurite plaques (Braak, H and Braak, E, Neurobio. of Aging. 1997 18(4):351-357). Structurally, the NFT's are principally comprised of paired helical filaments (PHF) comprised of two filamentous tau proteins twisted around one another with a crossover repeat of 80 nm and a width of 8-20 nm (Li, D., et al., 2008. Computational Biology 4(12) and Kidd, M 1963 Nature, 197:192). There are six stages (Braak stages I-VI) of tau deposition in the brain, which progress temporally at defined anatomical locations with the initial stages characterized primarily by the deposition of NFT's and NT's and the secondary stages further accompanied by NP (Braak, 1997). In Alzheimers Disease and other neuropathies, Braak's stages correlate well with clinical disease progression as demonstrated by increasing cognitive dysfunction. Severe cortical destruction which occurs around stages III-IV coincides with the first manifestations of the clinical onset of AD. Although no tau mutations have been identified in AD there is a strong correlation between NFT density and cognitive decline in AD (Brunden, K. R., Trojanowski, J. Q., and Lee, V. M. 2009 Nature Reviews 8:783-93).
[0016] New biomarkers and models of their temporal characteristics are becoming even more useful for the diagnosis and characterization of AD (Jack et al., 2010. Lancet 9:119-28). Specifically, tau deposition is associated with neurodegeneration in AD and an increase in CSF tau is an important indicator of tau pathologic changes and correlates well with clinical disease severity. A decrease in FDG-PET correlates well with increased CSF tau and both are valid indicators of synaptic dysfunction (Jack et al, ibid). This model of biomarker ordering, especially in mildly cognitive impaired individuals, has important implications for clinical trials. Potential therapeutics could be more accurately assessed for efficacy is they are able to change the trajectory of cognitive deterioration and individuals might be more selectively chosen for trials (Jack et al, ibid).
[0017] It is presently not known if tau is a causative factor in disease but it is likely that either a loss or gain for function results in pathology. In FTLD17, a missense mutation affects the alternative splicing of tau resulting in the disruption of the ratio of the 4R to 3R tau isoform. More of the 4R isoform with an extra repeat of the microtubule binding region may lead to overstabilization of the microtubules resulting in disease. Other post-translational events such as alterations in kinase activity and glycosylation could also cause hyperphosphorylation and result in disease or alternatively proteolytic cleavage could produce truncated tau products more inclined to aggregate (Brunden, ibid).
[0018] Recently tau toxicity has been re-emphasized as an important therapeutic target in neurodegerative tauopathies (Keystone Symposium, March 2009). Routes for developing therapeutics are either directed to inhibiting tau-phosphorylation kinases or seeking compounds effective in the modulation of tau aggregation and/or the dissolution or disruption of tau aggregates which may prove equally useful or more specific for the alleviation of tauopathies (Rafii, M and Aisen, P. 2009 BMC Medicine 7:7). A recent paper surveyed the efficacy of several classes of compounds for their ability to prevent tau aggregation and disaggregate pre-formed tau fibrils (Bulic et al.). Although there are general concerns regarding the toxicity of disassembled fibrils, Bulic et al., were able to show that reversing tau aggregation resulted in increased cell viability.
SUMMARY OF INVENTION
[0019] In a first aspect, provided herein are compounds such as, but not limited to:
[0000]
[0020] In a second aspect, this invention is a method of treating a synucleinopathy in a mammal, especially a human, by administration of a therapeutically effective amount of a compound of the first aspect of this invention, for example as a pharmaceutical composition. Methods using such compounds and compositions for disrupting, disaggregating and causing removal, reduction or clearance of α-synuclein fibrils and/or aggregates are provided thereby providing new treatments for synucleinopathies. The treatment of disease may also include the inhibiting the formation of α-synuclein fibrils and/or aggregates or providing neuroprotection for neurons at risk.
[0021] Also provided are any pharmaceutically-acceptable derivatives of the compounds of the first aspect of this invention, including salts, esters, enol ethers or esters, acetals, ketals, orthoesters, hemiacetals, hemiketals, solvates, hydrates or prodrugs of the compounds. Pharmaceutically-acceptable salts, include, but are not limited to, amine salts, alkali metal salts, such as but not limited to lithium, potassium and sodium, alkali earth metal salts, such as but not limited to barium, calcium and magnesium, transition metal salts, such as but not limited to zinc and other metal salts, such as but not limited to sodium hydrogen phosphate and disodium phosphate, and also including, but not limited to, salts of mineral acids, such as but not limited to hydrochlorides and sulfates, salts of organic acids, such as but not limited to acetates, lactates, malates, tartrates, citrates, ascorbates, succinates, butyrates, valerates and fumarates.
[0022] Pharmaceutical formulations for administration by an appropriate route and means containing effective concentrations of one or more of the compounds provided herein or pharmaceutically acceptable derivatives, such as salts, esters, enol ethers or esters, acetals, ketals, orthoesters, hemiacetals, hemiketals, solvates, hydrates or prodrugs, of the compounds that deliver amounts effective for the treatment of synucleinopathies, are also provided.
[0023] The formulations are compositions suitable for administration by any desired route and include solutions, suspensions, emulsions, tablets, dispersible tablets, pills, capsules, powders, dry powders for inhalation, sustained release formulations, aerosols for nasal and respiratory delivery, patches for transdermal delivery and any other suitable route. The compositions should be suitable for oral administration, parenteral administration by injection, including subcutaneously, intramuscularly or intravenously as an injectable aqueous or oily solution or emulsion, transdermal administration and other selected routes.
[0024] Also provided are methods for treatment, prevention or amelioration of one or more symptoms of synucleinopathies, including but not limited to diseases associated with the formation, deposition, accumulation, or persistence of alpha-synuclein.
[0025] Provided are methods for treatment, prevention or amelioration of one or more symptoms of synuclein diseases or synucleinopathies. In one embodiment, the methods inhibit or prevent α-synuclein/NAC fibril formation and/or aggregation, inhibit or prevent α-synuclein/NAC fibril growth, and/or cause disassembly, disruption, and/or disaggregation of preformed α-synuclein/NAC fibrils and α-synuclein/NAC-associated protein deposits and/or aggregates. Synuclein diseases include, but are not limited to Parkinson's disease, PDD, familial Parkinson's disease, Lewy body disease, the Lewy body variant of Alzheimer's disease, dementia with Lewy bodies (DLB), multiple system atrophy, and the Parkinsonism-dementia complex of Guam.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a graph illustrating that a compound of the invention causes a dose-dependent inhibition of of α-synuclein aggregation and fibril formation as assessed by Thioflavin T fluorometry.
[0027] FIG. 2 is a graph illustrating that a compound of the invention causes the dose-dependent inhibition of of α-synuclein aggregation and fibril formation as assessed by Congo Red binding.
[0028] FIG. 3 is a graph illustrating the rotenone dose-dependent increase in Thioflavin S fluorescence in BE-M17 neuroblastoma cells overexpressing A53T-mutant α-synuclein.
[0029] FIG. 4 is a graph illustrating that a compound of the invention causes dose-dependent inhibition of rotenone-induced cell death as assessed by the XTT cell viability assay.
[0030] FIG. 5 is a graph illustrating that a compound of the invention causes the dose-dependent inhibition of α-synuclein β-sheet formation as assessed by circular dichroism spectroscopy.
DETAILED DESCRIPTION OF THE INVENTION
A. Definitions
[0031] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this invention belongs. All patents, applications, published applications and other publications are incorporated by reference in their entirety. In the event that there is a plurality of definitions for a term herein, those in this section prevail unless stated otherwise.
[0032] As used herein, “Synuclein diseases” or “synucleinopathies” are diseases associated with the formation, deposition, accumulation, or persistence of synuclein fibrils, including, but not limited to α-synuclein fibrils. Such diseases include, but are not limited to Parkinson's disease, Familial Parkinson's disease, PDD, Lewy body disease, the Lewy body variant of Alzheimer's disease, dementia with Lewy bodies, multiple system atrophy, and the Parkinsonism-dementia complex of Guam.
[0033] Aggregation or Fibrillogenesis refers to the formation, deposition, accumulation and/or persistence of synuclein fibrils, filaments, inclusions, deposits, and/or NAC fibrils, filaments, inclusions, deposits, and/or aggregates or the like.
[0034] Inhibition of aggregation or fibrillogenesis refers to the inhibition of formation, deposition, accumulation and/or persistence of such fibrils or fibril-like deposits.
[0035] Disruption of fibrils or fibrillogenesis refers to the disruption of pre-formed α-synuclein fibrils, that usually exist in a pre-dominant β-pleated sheet secondary structure. Such disruption by compounds provided herein may involve marked reduction or disassembly of synuclein fibrils as assessed by various methods such as Thioflavin T fluorometry, Congo red binding, SDS-PAGE/Western blotting, as demonstrated by the Examples presented in this application.
[0036] “Mammal” includes both humans and non-human mammals, such as companion animals (cats, dogs, and the like), laboratory animals (such as mice, rats, guinea pigs, and the like) and farm animals (cattle, horses, sheep, goats, swine, and the like).
[0037] “Pharmaceutically acceptable excipient” means an excipient that is conventionally useful in preparing a pharmaceutical composition that is generally safe, non-toxic, and desirable, and includes excipients that are acceptable for veterinary use or for human pharmaceutical use. Such excipients may be solid, liquid, semisolid, or, in the case of an aerosol composition, gaseous.
[0038] A “therapeutically effective amount” means the amount that, when administered to a subject or animal for treating a disease, is sufficient to affect the desired degree of treatment, prevention or symptom amelioration for the disease. A “therapeutically effective amount” or a “therapeutically effective dosage” in certain embodiments inhibits, reduces, disrupts, disassembles synuclein fibril formation, deposition, accumulation and/or persistence, or treats, prevents, or ameliorates one or more symptoms of a disease associated with these conditions, such as a synucleinopathy, in a measurable amount in one embodiment, by at least 20%, in other embodiment, by at least 40%, in other embodiment by at least 60%, and in still other embodiment by at least 80%, relative to an untreated subject. Effective amounts of a compound provided herein or composition thereof for treatment of a mammalian subject are about 0.1 to about 1000 mg/Kg of body weight of the subject/day, such as from about 1 to about 100 mg/Kg/day, in other embodiment, from about 10 to about 100 mg/Kg/day. A broad range of disclosed composition dosages are believed to be both safe and effective.
[0039] The term “sustained release component” is defined herein as a compound or compounds, including, but not limited to, polymers, polymer matrices, gels, permeable membranes, liposomes, microspheres, or the like, or a combination thereof, that facilitates the sustained release of the active ingredient.
[0040] If the complex is water-soluble, it may be formulated in an appropriate buffer, for example, phosphate buffered saline, or other physiologically compatible solutions. Alternatively, if the resulting complex has poor solubility in aqueous solvents, then it may be formulated with a non-ionic surfactant such as Tween, or polyethylene glycol. Thus, the compounds and their physiologically suitable solvents may be formulated for administration by inhalation or insufflation (either through the mouth or the nose) or oral, buccal, parenteral, or rectal administration, as examples.
[0041] As used herein, pharmaceutically acceptable derivatives of a compound include salts, esters, enol ethers, enol esters, acetals, ketals, orthoesters, hemiacetals, hemiketals, solvates, hydrates or prodrugs thereof. Such derivatives may be readily prepared by those of skill in this art using known methods for such derivatization. The compounds produced may be administered to animals or humans without substantial toxic effects and either are pharmaceutically active or are prodrugs. Pharmaceutically acceptable salts include, but are not limited to, amine salts, such as but not limited to N,N′-dibenzylethylenediamine, chloroprocaine, choline, ammonia, diethanolamine and other hydroxyalkylamines, ethylenediamine, N-methylglucamine, procaine, N-benzylphenethylamine, 1-para-chlorobenzyl-2-pyrrolidin-1′-ylmethyl-benzimidazole, diethylamine and other alkylamines, piperazine and tris(hydroxymethyl)aminomethane; alkali metal salts, such as but not limited to lithium, potassium and sodium; alkali earth metal salts, such as but not limited to barium, calcium and magnesium; transition metal salts, such as but not limited to zinc; and other metal salts, such as but not limited to sodium hydrogen phosphate and disodium phosphate; and also including, but not limited to, salts of mineral acids, such as but not limited to hydrochlorides and sulfates; and salts of organic acids, such as but not limited to acetates, lactates, malates, tartrates, citrates, ascorbates, succinates, butyrates, valerates and fumarates. Pharmaceutically acceptable esters include, but are not limited to, alkyl, alkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, cycloalkyl and heterocyclyl esters of acidic groups, including, but not limited to, carboxylic acids, phosphoric acids, phosphinic acids, sulfonic acids, sulfinic acids and boronic acids. Pharmaceutically acceptable enol ethers include, but are not limited to, derivatives of formula C═C(OR) where R is hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, cycloalkyl or heterocyclyl. Pharmaceutically acceptable enol esters include, but are not limited to, derivatives of formula C═C(OC(O)R) where R is hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, cycloalkyl or heterocyclyl. Pharmaceutically acceptable solvates and hydrates are complexes of a compound with one or more solvent or water molecules, or 1 to about 100, or 1 to about 10, or one to about 2, 3 or 4, solvent or water molecules.
[0042] As used herein, treatment means any manner in which one or more of the symptoms of a disease or disorder are ameliorated or otherwise beneficially altered. For example, slowing or arresting disease development, providing relief from the symptoms or side-effects of the disease, and relieving the disease by causing regression of the disease, such as by disruption of pre-formed synuclein fibrils could all be considered as treatment.
[0043] As used herein, amelioration of the symptoms of a particular disorder by administration of a particular compound or pharmaceutical composition refers to any lessening, whether permanent or temporary, lasting or transient that can be attributed to or associated with administration of the composition.
[0044] As used herein, “NAC” (non-Aβ component) is a 35-amino acid peptide fragment of α-synuclein, which like α-synuclein, has the ability to form fibrils when incubated at 37° C., and is positive with stains such as Congo red (demonstrating a red/green birefringence when viewed under polarized light) and Thioflavin S (demonstrating positive fluorescence) (Hashimoto et al., Brain Res, 799:301-306, 1998; Ueda et al., Proc. Natl. Acad. Sci. U.S.A. 90:11282-11286, 1993). Inhibition of NAC fibril formation, deposition, accumulation, aggregation, and/or persistence is believed to be effective treatment for a number of diseases involving α-synuclein, such as Parkinson's disease, Lewy body disease and multiple system atrophy.
[0045] As used herein, a prodrug is a compound that, upon in vivo administration, is metabolized by one or more steps or processes or otherwise converted to the biologically, pharmaceutically or therapeutically active form of the compound. To produce a prodrug, the pharmaceutically active compound is modified such that the active compound will be regenerated by metabolic processes. The prodrug may be designed to alter the metabolic stability or the transport characteristics of a drug, to mask side effects or toxicity, to improve the flavor of a drug or to alter other characteristics or properties of a drug. By virtue of knowledge of pharmacodynamic processes and drug metabolism in vivo, those of skill in this art, once a pharmaceutically active compound is known, can design prodrugs of the compound (see, e.g., Nogrady (1985) Medicinal Chemistry A Biochemical Approach , Oxford University Press, New York, pages 388-392).
[0046] It is to be understood that the compounds provided herein may contain chiral centers. Such chiral centers may be of either the (R) or (S) configuration, or may be a mixture thereof. Thus, the compounds provided herein may be enantiomerically pure, or be stereoisomeric or diastereomeric mixtures. It is to be understood that the chiral centers of the compounds provided herein may undergo epimerization in vivo. As such, one of skill in the art will recognize that administration of a compound in its (R) form is equivalent, for compounds that undergo epimerization in vivo, to administration of the compound in its (S) form.
[0047] As used herein, the abbreviations for any protective groups, amino acids and other compounds, are, unless indicated otherwise, in accord with their common usage, recognized abbreviations, or the IUPAC-IUB Commission on Biochemical Nomenclature (see, (1972) Biochem. 11:942-944).
B. Compounds
[0048] Provided herein are compounds and pharmaceutical compositions containing compounds, not limited to those shown above in the summary section and in the following examples.
C. Preparation of the Compounds
[0049] The compounds provided herein can be prepared by standard synthetic methods known in the art, and are shown in general schemes provided herein. The examples that follow describe the exemplary embodiments and are not purported to limit the scope of the claimed subject matter. It is intended that the specification, together with the following examples, be considered exemplary only, with the scope and spirit of the claimed subject matter being indicated by the claims that follow these examples. Other embodiments within the scope of claims herein will be apparent to one skilled in the art from consideration of the specification as described herein.
[0050] The starting materials and reagents used in preparing these compounds are either available from commercial suppliers such as the Aldrich Chemical Company (Milwaukee, Wis.), Bachem (Torrance, Calif.), Sigma (St. Louis, Mo.), or Lancaster Synthesis Inc. (Windham, N.H.) or are prepared by methods well known to a person of ordinary skill in the art, following procedures described in such references as Fieser and Fieser's Reagents for Organic Synthesis , vols. 1-17, John Wiley and Sons, New York, N.Y., 1991 ; Rodd's Chemistry of Carbon Compounds , vols. 1-5 and supps., Elsevier Science Publishers, 1989; Organic Reactions, vols. 1-40, John Wiley and Sons, New York, N.Y., 1991; March J.: Advanced Organic Chemistry, 4th ed., John Wiley and Sons, New York, N.Y.; and Larock: Comprehensive Organic Transformations , VCH Publishers, New York, 1989.
[0051] In most cases, protective groups for the hydroxy groups are introduced and finally removed. Suitable protective groups are described in Greene et al., Protective Groups in Organic Synthesis , Second Edition, John Wiley and Sons, New York, 1991. Other starting materials or early intermediates may be prepared by elaboration of the materials listed above, for example, by methods well known to a person of ordinary skill in the art. The starting materials, intermediates, and compounds provided herein may be isolated and purified using conventional techniques, including precipitation, filtration, distillation, crystallization, chromatography, and the like. The compounds may be characterized using conventional methods, including physical constants and spectroscopic methods.
D. Pharmaceutical Compositions and Administration
[0052] The compounds provided herein can be used as such, be administered in the form of pharmaceutically acceptable salts derived from inorganic or organic acids, or used in combination with one or more pharmaceutically acceptable excipients. The phrase “pharmaceutically acceptable salt” means those salts which are, within the scope of sound medical judgment, suitable for use in contact with the tissues without undue toxicity, irritation, allergic response, and the like, and are commensurate with a reasonable benefit/risk ratio. Pharmaceutically acceptable salts are well known in the art. The salts can be prepared either in situ during the final isolation and purification of the compounds provided herein or separately by reacting the acidic or basic drug substance with a suitable base or acid respectively. Typical salts derived from organic or inorganic acids salts include, but are not limited to hydrochloride, hydrobromide, hydroiodide, acetate, adipate, alginate, citrate, aspartate, benzoate, bisulfate, gluconate, fumarate, hydroiodide, lactate, maleate, oxalate, palmitoate, pectinate, succinate, tartrate, phosphate, glutamate, and bicarbonate. Typical salts derived from organic or inorganic bases include, but are not limited to lithium, sodium, potassium, calcium, magnesium, ammonium, monoalkylammonium such as meglumine, dialkylammonium, trialkylammonium, and tetralkylammonium. The mode of administration of the pharmaceutical compositions can be oral, rectal, intravenous, intramuscular, intracisternal, intravaginal, intraperitoneal, bucal, subcutaneous, intrasternal, nasal, or topical. The compositions can also be delivered at the target site through a catheter, an intracoronary stent (a tubular device composed of a fine wire mesh), a biodegradable polymer, or biological carriers including, but are not limited to antibodies, biotin-avidin complexes, and the like. Dosage forms for topical administration of a compound provided herein include powders, sprays, ointments and inhalants. The active compound is mixed under sterile conditions with a pharmaceutically acceptable carrier and any needed preservatives, buffers or propellants. Ophthalmic formulations, eye ointments, powders and solutions are also provided herein.
[0053] Actual dosage levels of active ingredients and the mode of administration of the pharmaceutical compositions provided herein can be varied in order to achieve the effective therapeutic response for a particular patient. The phrase “therapeutically effective amount” of the compound provided herein means a sufficient amount of the compound to treat disorders, at a reasonable benefit/risk ratio applicable to any medical treatment. It will be understood, however, that the total daily usage of the compounds and compositions of the provided will be decided by the attending physician within the scope of sound medical judgment. The total daily dose of the compounds provided herein may range from about 0.0001 to about 1000 mg/kg/day. For purposes of oral administration, doses can be in the range from about 0.001 to about 50 mg/kg/day. If desired, the effective daily dose can be divided into multiple doses for purposes of administration; consequently, single dose compositions may contain such amounts or submultiples thereof to make up the daily dose. The specific therapeutically effective dose level for any particular patient will depend upon a variety of factors including the disorder being treated and the severity of the disorder; medical history of the patient, activity of the specific compound employed; the specific composition employed, age, body weight, general health, sex and diet of the patient, the time of administration, route of administration, the duration of the treatment, rate of excretion of the specific compound employed, drugs used in combination or coincidental with the specific compound employed; and the like.
[0054] The compounds provided can be formulated together with one or more non-toxic pharmaceutically acceptable diluents, carriers, adjuvants, and antibacterial and antifungal agents such as parabens, chlorobutanol, phenol, sorbic acid, and the like. Proper fluidity can be maintained, for example, by the use of coating materials such as lecithin, by the maintenance of the required particle size in the case of dispersions, and by the use of surfactants. In some cases, in order to prolong the effect of the drug, it is desirable to decrease the rate of absorption of the drug from subcutaneous or intramuscular injection. This can be accomplished by suspending crystalline or amorphous drug substance in a vehicle having poor water solubility such as oils. The rate of absorption of the drug then depends upon its rate of dissolution, which, in turn, may depend upon crystal size and crystalline form. Prolonged absorption of an injectable pharmaceutical form can be achieved by the use of absorption delaying agents such as aluminum monostearate or gelatin.
[0055] The compound provided herein can be administered enterally or parenterally in solid or liquid forms. Compositions suitable for parenteral injection may comprise physiologically acceptable, isotonic sterile aqueous or nonaqueous solutions, dispersions, suspensions, or emulsions, and sterile powders for reconstitution into sterile injectable solutions or dispersions. Examples of suitable aqueous and nonaqueous carriers, diluents, solvents or vehicles include water, ethanol, polyols (propyleneglycol, polyethyleneglycol, glycerol, and the like), vegetable oils (such as olive oil), injectable organic esters such as ethyl oleate, and suitable mixtures thereof. These compositions can also contain adjuvants such as preserving, wetting, emulsifying, and dispensing agents. Suspensions, in addition to the active compounds, may contain suspending agents such as ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar-agar and tragacanth, or mixtures of these substances.
[0056] The compounds provided herein can also be administered by injection or infusion, either subcutaneously or intravenously, or intramuscularly, or intrastemally, or intranasally, or by infusion techniques in the form of sterile injectable or oleaginous suspension. The compound may be in the form of a sterile injectable aqueous or oleaginous suspensions. These suspensions may be formulated according to the known art using suitable dispersing of wetting agents and suspending agents that have been described above. The sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent for example, as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oils may be conventionally employed including synthetic mono- or diglycerides. In addition fatty acids such as oleic acid find use in the preparation of injectables. Dosage regimens can be adjusted to provide the optimum therapeutic response. For example, several divided dosages may be administered daily or the dosage may be proportionally reduced as indicated by the exigencies of the therapeutic situation.
[0057] Injectable dosage forms are made by forming microencapsule matrices of the drug in biodegradable polymers such as polylactide-polyglycolide. Depending upon the ratio of drug to polymer and the nature of the particular polymer employed, the rate of drug release can be controlled. Examples of other biodegradable polymers include poly(orthoesters) and poly(anhydrides). Depot injectable formulations are also prepared by entrapping the drug in liposomes or microemulsions which are compatible with body tissues. The injectable formulations can be sterilized, for example, by filtration through a bacterial-retaining filter or by incorporating sterilizing agents in the form of sterile solid compositions which can be dissolved or dispersed in sterile water or other sterile injectable medium just prior to use.
[0058] Solid dosage forms for oral administration include capsules, tablets, pills, powders and granules. In such solid dosage forms, the active compound may be mixed with at least one inert, pharmaceutically acceptable excipient or carrier, such as sodium citrate or dicalcium phosphate and/or (a) fillers or extenders such as starches, lactose, sucrose, glucose, mannitol and silicic acid; (b) binders such as carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidone, sucrose and acacia; (c) humectants such as glycerol; (d) disintegrating agents such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates and sodium carbonate; (e) solution retarding agents such as paraffin; (f) absorption accelerators such as quaternary ammonium compounds; (g) wetting agents such as cetyl alcohol and glycerol monostearate; (h) absorbents such as kaolin and bentonite clay and (i) lubricants such as talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate and mixtures thereof. In the case of capsules, tablets and pills, the dosage form may also comprise buffering agents. Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like.
[0059] The solid dosage forms of tablets, dragees, capsules, pills and granules can be prepared with coatings and shells such as enteric coatings and other coatings well-known in the pharmaceutical formulating art. They may optionally contain opacifying agents and may also be of a composition such that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner. Examples of embedding compositions which can be used include polymeric substances and waxes. Tablets contain the compound in admixture with non-toxic pharmaceutically acceptable excipients that are suitable for the manufacture of tablets. These excipients may be for example, inert diluents, such as calcium carbonate, sodium carbonate, lactose, calcium phosphate or sodium phosphate; granulating and disintegrating agents, for example, maize starch or alginic acid; binding agents, for example, maize starch, gelatin or acacia, and lubricating agents, for example, magnesium stearate or stearic acid or tale. The tablets may be uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glycerol monostearate or glycerol distearate may be employed. Formulations for oral use may also be presented as hard gelatin capsules wherein the compound is mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin, or as soft gelatin capsules wherein the active ingredient is mixed with water or an oil medium, for example, peanut oil, liquid paraffin or olive oil.
[0060] Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, solutions, suspensions, syrups and elixirs. In addition to the active compounds, the liquid dosage forms may contain inert diluents commonly used in the art such as, for example, water or other solvents, solubilizing agents and emulsifiers such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethyl formamide, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor and sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan and mixtures thereof. Besides inert diluents, the oral compositions may also include adjuvants such as wetting agents, emulsifying and suspending agents, sweetening, flavoring and perfuming agents.
[0061] Aqueous suspensions contain the compound in admixture with excipients suitable for the manufacture of aqueous suspensions. Such excipients are suspending agents, for example, sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethyl cellulose, sodium alginate, polyvinylpyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents may be naturally occurring phosphatides, for example lecithin, or condensation products of an alkylene oxide with fatty acids, for example polyoxyethylene stearate, or condensation products of ethylene oxide with long chain aliphatic alcohols, for example, heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids such as hexitol such as polyoxyethylene sorbitol monooleate, or condensation products of ethylene oxide with partial esters from fatty acids and a hexitol anhydrides, for example, polyethylene sorbitan monooleate. The aqueous suspensions may also contain one or more preservatives, for example, ethyl or n-propyl p-hydroxybenzoate, one or more coloring agents, one or more flavoring agents, or one or more sweetening agents, such as sucrose or saccharin.
[0062] Oily suspensions may be formulated by suspending the compound in a vegetable oil, for example arachis oil, olive oil, sesame oil, or coconut oil or in a mineral oil such as liquid paraffin. The oily suspensions may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol. Sweetening agents, such as those set forth below, and flavoring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an antioxidant such as ascorbic acid. Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting agent, a suspending agent and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified by those already described above. Additional excipients, for example sweetening, flavoring and agents, may also be present.
[0063] The compounds provided herein may also be in the form of oil-in-water emulsions. The oily phase may be a vegetable oil, for example olive oil or arachis oils, or a mineral oil, for example liquid paraffin or mixtures of these. Suitable emulsifying agents may be naturally-occurring gums, for example gum acacia or gum tragacanth, naturally occurring phosphatides, for example soy bean, lecithin, and occurring phosphatides, for example soy bean, lecithin, and esters or partial esters derived from fatty acids and hexitol anhydrides, for example sorbitan monooleate, and condensation products of the said partial esters with ethylene oxide, for example polyoxyethylene sorbitan monooleate. The emulsion may also contain sweetening and flavoring agents. Syrups and elixirs may be formulated with sweetening agents, for example, glycerol, sorbitol or sucrose. Such formulations may also contain a demulcent, preservative and flavoring and coloring agent.
[0064] In one embodiment, the compounds are formulated in dosage unit form for ease of administration and uniformity of dosage. Dosage unit form as used herein refers to physically discrete units suited as unitary dosages for the subjects to be treated; each containing a therapeutically effective quantity of the compound and at least one pharmaceutical excipient. A drug product will comprise a dosage unit form within a container that is labeled or accompanied by a label indicating the intended method of treatment, such as the treatment of a disease associated with α-synuclein/NAC fibril formation such as Parkinson's disease. Compositions for rectal or vaginal administration are preferably suppositories which can be prepared by mixing the compounds provided herein with suitable non-irritating excipients or carriers such as cocoa butter, polyethylene glycol or a suppository wax which are solid at room temperature but liquid at body temperature and therefore melt in the rectum or vaginal cavity and release the active compound.
[0065] Compounds provided herein can also be administered in the form of liposomes. Methods to form liposomes are known in the art (Prescott, Ed., Methods in Cell Biology 1976, Volume XIV, Academic Press, New York, N.Y.) As is known in the art, liposomes are generally derived from phospholipids or other lipid substances. Liposomes are formed by mono- or multi-lamellar hydrated liquid crystals which are dispersed in an aqueous medium. Any non-toxic, physiologically acceptable and metabolizable lipid capable of forming liposomes can be used. The present compositions in liposome form can contain, in addition to a compound provided herein, stabilizers, preservatives, excipients and the like. The preferred lipids are natural and synthetic phospholipids and phosphatidyl cholines (lecithins).
[0066] The compounds provided herein can also be administered in the form of a ‘prodrug’ wherein the active pharmaceutical ingredients are released in vivo upon contact with hydrolytic enzymes such as esterases and phophatases in the body. The term “pharmaceutically acceptable prodrugs” as used herein represents those prodrugs of the compounds provided herein, which are, within the scope of sound medical judgment, suitable for use in contact with the tissues without undue toxicity, irritation, allergic response, and the like, commensurate with a reasonable benefit/risk ratio, and effective for their intended use. A thorough discussion is provided in T. Higuchi and V. Stella (Higuchi, T. and Stella, V. Pro-drugs as Novel Delivery Systems, V. 14 of the A.C.S. Symposium Series; Edward B. Roche, Ed., Bioreversible Carriers in Drug Design 1987, American Pharmaceutical Association and Pergamon Press), which is incorporated herein by reference.
[0067] The compounds provided herein, or pharmaceutically acceptable derivatives thereof, may also be formulated to be targeted to a particular tissue, receptor, or other area of the body of the subject to be treated. Many such targeting methods are well known to those of skill in the art. All such targeting methods are contemplated herein for use in the instant compositions. For non-limiting examples of targeting methods, see, e.g., U.S. Pat. Nos. 6,316,652, 6,274,552, 6,271,359, 6,253,872, 6,139,865, 6,131,570, 6,120,751, 6,071,495, 6,060,082, 6,048,736, 6,039,975, 6,004,534, 5,985,307, 5,972,366, 5,900,252, 5,840,674, 5,759,542 and 5,709,874.
[0068] In one embodiment, liposomal suspensions, including tissue-targeted liposomes, such as tumor-targeted liposomes, may also be suitable as pharmaceutically acceptable carriers. These may be prepared according to methods known to those skilled in the art. For example, liposome formulations may be prepared as described in U.S. Pat. No. 4,522,811. Briefly, liposomes such as multilamellar vesicles (MLVs) may be formed by drying down egg phosphatidyl choline and brain phosphatidyl serine (7:3 molar ratio) on the inside of a flask. A solution of a compound provided herein in phosphate buffered saline lacking divalent cations (PBS) is added and the flask shaken until the lipid film is dispersed. The resulting vesicles are washed to remove unencapsulated compound, pelleted by centrifugation, and then resuspended in PBS.
Sustained Release Formulations
[0069] Also provided are sustained release formulations to deliver the compounds to the desired target (i.e. brain) at high circulating levels (between 10 −9 and 10 −4 M). In a certain embodiment for the treatment of Parkinson's disease, the circulating levels of the compounds are maintained up to 10 −7 M. The levels are either circulating in the patient systemically, or in one embodiment, present in brain tissue, and in other embodiments, localized to the α-synuclein fibril deposits in brain.
[0070] It is understood that the compound levels are maintained over a certain period of time as is desired and can be easily determined by one skilled in the art. In one embodiment, the administration of a sustained release formulation is effected so that a constant level of therapeutic compound is maintained between 10 −8 and 10 −6 M between 48 to 96 hours in the sera.
[0071] Such sustained and/or timed release formulations may be made by sustained release means of delivery devices that are well known to those of ordinary skill in the art, such as those described in U.S. Pat. Nos. 3,845,770; 3,916,899; 3,536,809; 3,598,123; 4,008,719; 4,710,384; 5,674,533; 5,059,595; 5,591,767; 5,120,548; 5,073,543; 5,639,476; 5,354,556 and 5,733,566, the disclosures of which are each incorporated herein by reference. These pharmaceutical compositions can be used to provide slow or sustained release of one or more of the active compounds using, for example, hydroxypropylmethyl cellulose, other polymer matrices, gels, permeable membranes, osmotic systems, multilayer coatings, microparticles, liposomes, microspheres, or the like. Suitable sustained release formulations known to those skilled in the art, including those described herein, may be readily selected for use with the pharmaceutical compositions provided herein. Thus, single unit dosage forms suitable for oral administration, such as, but not limited to, tablets, capsules, gelcaps, caplets, powders and the like, that are adapted for sustained release are contemplated herein.
[0072] In one embodiment, the sustained release formulation contains active compound such as, but not limited to, microcrystalline cellulose, maltodextrin, ethylcellulose, and magnesium stearate. As described above, all known methods for encapsulation which are compatible with properties of the disclosed compounds are contemplated herein. The sustained release formulation is encapsulated by coating particles or granules of the pharmaceutical compositions provided herein with varying thickness of slowly soluble polymers or by microencapsulation. In one embodiment, the sustained release formulation is encapsulated with a coating material of varying thickness (e.g. about 1 micron to 200 microns) that allow the dissolution of the pharmaceutical composition about 48 hours to about 72 hours after administration to a mammal. In another embodiment, the coating material is a food-approved additive.
[0073] In another embodiment, the sustained release formulation is a matrix dissolution device that is prepared by compressing the drug with a slowly soluble polymer carrier into a tablet. In one embodiment, the coated particles have a size range between about 0.1 to about 300 microns, as disclosed in U.S. Pat. Nos. 4,710,384 and 5,354,556, which are incorporated herein by reference in their entireties. Each of the particles is in the form of a micromatrix, with the active ingredient uniformly distributed throughout the polymer.
[0074] Sustained release formulations such as those described in U.S. Pat. No. 4,710,384, which is incorporated herein by reference in its entirety, having a relatively high percentage of plasticizer in the coating in order to permit sufficient flexibility to prevent substantial breakage during compression are disclosed. The specific amount of plasticizer varies depending on the nature of the coating and the particular plasticizer used. The amount may be readily determined empirically by testing the release characteristics of the tablets formed. If the medicament is released too quickly, then more plasticizer is used. Release characteristics are also a function of the thickness of the coating. When substantial amounts of plasticizer are used, the sustained release capacity of the coating diminishes. Thus, the thickness of the coating may be increased slightly to make up for an increase in the amount of plasticizer. Generally, the plasticizer in such an embodiment will be present in an amount of about 15 to 30% of the sustained release material in the coating, in one embodiment 20 to 25%, and the amount of coating will be from 10 to 25% of the weight of the active material, and in another embodiment, 15 to 20% of the weight of active material. Any conventional pharmaceutically acceptable plasticizer may be incorporated into the coating.
[0075] The compounds provided herein can be formulated as a sustained and/or timed release formulation. All sustained release pharmaceutical products have a common goal of improving drug therapy over that achieved by their non-sustained counterparts. Ideally, the use of an optimally designed sustained release preparation in medical treatment is characterized by a minimum of drug substance being employed to cure or control the condition. Advantages of sustained release formulations may include: 1) extended activity of the composition, 2) reduced dosage frequency, and 3) increased patient compliance. In addition, sustained release formulations can be used to affect the time of onset of action or other characteristics, such as blood levels of the composition, and thus can affect the occurrence of side effects.
[0076] The sustained release formulations provided herein are designed to initially release an amount of the therapeutic composition that promptly produces the desired therapeutic effect, and gradually and continually release of other amounts of compositions to maintain this level of therapeutic effect over an extended period of time. In order to maintain this constant level in the body, the therapeutic composition must be released from the dosage form at a rate that will replace the composition being metabolized and excreted from the body.
[0077] The sustained release of an active ingredient may be stimulated by various inducers, for example pH, temperature, enzymes, water, or other physiological conditions or compounds.
[0078] Preparations for oral administration may be suitably formulated to give controlled release of the active compound. In one embodiment, the compounds are formulated as controlled release powders of discrete microparticles that can be readily formulated in liquid form. The sustained release powder comprises particles containing an active ingredient and optionally, an excipient with at least one non-toxic polymer.
[0079] The powder can be dispersed or suspended in a liquid vehicle and will maintain its sustained release characteristics for a useful period of time. These dispersions or suspensions have both chemical stability and stability in terms of dissolution rate. The powder may contain an excipient comprising a polymer, which may be soluble, insoluble, permeable, impermeable, or biodegradable. The polymers may be polymers or copolymers. The polymer may be a natural or synthetic polymer. Natural polymers include polypeptides (e.g., zein), polysaccharides (e.g., cellulose), and alginic acid. Representative synthetic polymers include those described, but not limited to, those described in column 3, lines 33-45 of U.S. Pat. No. 5,354,556, which is incorporated by reference in its entirety. Particularly suitable polymers include those described, but not limited to those described in column 3, line 46-column 4, line 8 of U.S. Pat. No. 5,354,556 which is incorporated by reference in its entirety.
[0080] The sustained release compositions provided herein may be formulated for parenteral administration, e.g., by intramuscular injections or implants for subcutaneous tissues and various body cavities and transdermal devices. In one embodiment, intramuscular injections are formulated as aqueous or oil suspensions. In an aqueous suspension, the sustained release effect is due to, in part, a reduction in solubility of the active compound upon complexation or a decrease in dissolution rate. A similar approach is taken with oil suspensions and solutions, wherein the release rate of an active compound is determined by partitioning of the active compound out of the oil into the surrounding aqueous medium. Only active compounds which are oil soluble and have the desired partition characteristics are suitable. Oils that may be used for intramuscular injection include, but are not limited to, sesame, olive, arachis, maize, almond, soybean, cottonseed and castor oil.
[0081] A highly developed form of drug delivery that imparts sustained release over periods of time ranging from days to years is to implant a drug-bearing polymeric device subcutaneously or in various body cavities. The polymer material used in an implant, which must be biocompatible and nontoxic, include but are not limited to hydrogels, silicones, polyethylenes, ethylene-vinyl acetate copolymers, or biodegradable polymers.
Article of Manufacture
[0082] The compounds or pharmaceutically acceptable derivatives may be packaged as articles of manufacture containing packaging material, a compound or pharmaceutically acceptable derivative thereof provided herein, which is effective for treatment, prevention or amelioration of one or more symptoms of synuclein diseases, within the packaging material, and a label that indicates that the compound or composition, or pharmaceutically acceptable derivative thereof, is used for treatment, prevention or amelioration of one or more symptoms of synuclein diseases. The articles of manufacture provided herein contain packaging materials. Packaging materials for use in packaging pharmaceutical products are well known to those of skill in the art. See, e.g., U.S. Pat. Nos. 5,323,907, 5,052,558 and 5,033,252. Examples of pharmaceutical packaging materials include, but are not limited to, blister packs, bottles, tubes, inhalers, pumps, bags, vials, containers, syringes, bottles, and any packaging material suitable for a selected formulation and intended mode of administration and treatment. A wide array of formulations of the compounds and compositions provided herein are contemplated as are a variety of treatments for synuclein diseases.
E. Evaluation of the Activity of the Compounds
[0083] The biological activity of the compounds provided herein as disruptors/inhibitors of Parkinson's disease α-synuclein fibrils was assessed by determining the efficacy of the compounds to cause a disassembly/disruption of pre-formed Parkinson's disease α-synuclein fibrils. In one study, Thioflavin T fluorometry was used to determine the effects of the compounds, and of anegative control reference compound). In this assay Thioflavin T binds specifically to fibrillar protein, and this binding produces a fluorescence enhancement at 485 nm that is directly proportional to the amount of fibrils present. The higher the fluorescence, the greater the amount of fibrils present (Naki et al, Lab. Invest. 65:104-110, 1991; Levine III, Protein Sci. 2:404-410, 1993; Amyloid: Int. J. Exp. Clin. Invest. 2:1-6, 1995).
[0084] In the Congo red binding assay the ability of a given test compound to alter α-synuclein fibril binding to Congo red was quantified. In this assay, α-synuclein fibrils and test compounds were incubated for 2 days and then vacuum filtered through a 0.2 μM filter. The amount of α-synuclein fibrils retained in the filter was then quantitated following staining of the filter with Congo red. After appropriate washing of the filter, any lowering of the Congo red color on the filter in the presence of the test compound (compared to the Congo red staining of the protein in the absence of the test compound) was indicative of the test compound's ability to diminish/alter the amount of aggregated and congophilic α-synuclein fibrils.
F. Combination therapy
[0085] In another embodiment, the compounds may be administered in combination, or sequentially, with another therapeutic agent. Such other therapeutic agents include those known for treatment, prevention, or amelioration of one or more symptoms of synuclein diseases. Such therapeutic agents include, but are not limited to; carbidopa/levodopa (Sinemet, Stalevo, Parcopa), dopamine agonists (Apokyn, Parlodel, Neupro, Mirapex, Requip), anticholinergics (Cogentin, Artane), MAO-B inhibitors (Eldepryl, Carbex, Zelapar, Azilect), COMT inhibitors (Comtan, Tamar), and other medications like Symmetrel and Exelon.
G. Methods of Use of the Compounds and Compositions
[0086] The compounds and compositions provided herein are useful in methods of treatment, prevention, or amelioration of one or more symptoms of synucleopathies, including but not limited to diseases associated with the formation, deposition, accumulation, or persistence of synuclein fibrils. Also provided are methods to inhibit or prevent α-synuclein/NAC fibril formation and/or aggregation, methods to inhibit or prevent α-synuclein/NAC fibril growth, and methods to cause disassembly, disruption, and/or disaggregation of preformed α-synuclein/NAC fibrils and α-synuclein/NAC-associated protein deposits.
[0087] In certain embodiments, the synuclein diseases or synucleinopathies treated, prevented or whose symptoms are ameliorated by the compounds and compositions provided herein include, but are not limited to diseases associated with the formation, deposition, accumulation, or persistence of synuclein fibrils, including α-synuclein fibrils and/or aggregates. In certain embodiments, such diseases include Parkinson's disease, PDD, familial Parkinson's disease, Lewy body disease, the Lewy body variant of Alzheimer's disease, dementia with Lewy bodies, multiple system atrophy, and the Parkinsonism-dementia complex of Guam.
[0088] The following non-limiting Examples are given by way of illustration only and are not considered a limitation of the subject matter, many apparent variations of which are possible without departing from the spirit or scope thereof.
EXAMPLES
Example 1
Synthesis of SA-52
[0089]
[0090] 3,4-dimethoxybenzoic acid (1) (1.00 g, 5.5 mmol) was slurried in 5 mL of DCM. Oxalyl chloride (0.9 mL, 10.5 mmol) was then added, and five drops of DMF were added to initiate the reaction. The mixture was stirred overnight during which time it became a yellow solution. The solution was concentrated and dried in vacuo to remove the solvent and oxalyl chloride. The resultant solid was redissolved in 7 mL of DCM, cooled to −78° C., and 1.5 mL of pyridine was added. Then, 0.696 g of 2-bromo-4,5-dimethoxy aniline (3 mmol) was added in 5 mL of DCM. A solid formed causing stirring to be difficult, and therefore, an additional 6 mL portion of DCM was added. The mixture was warmed to 23° C., and after the reaction was complete, quenched with 20 mL of water. The layers were separated, the organic was washed with 20 mL of brine, dried with Na 2 SO 4 , and concentrated. The crude product was purified by column chromatography and then PTLC (0.5% MeOH in DCM as eluent) to give 1.05 g (88% yield) of benzamide (2) as an off-white solid. NMR (200 MHz, CDCl 3 ) δ 8.25 (bs, 2H, overlapping peak), 7.57 (d, J=2 Hz, 1H), 7.48 (dd, J=2 Hz, 8.4 Hz, 1H), 7.06 (s, 1H), 6.98 (d, J=8.4 Hz, 1H), 4.09-3.99 (3 overlapping singlets, 9H), 3.90 (s, 3H).
[0091] To 0.049 g (0.14 mmol) of 2 in 3 mL of DCM was added 2.5 mL 1 M BBr 3 in DCM. The solution was stirred 18 h. The mixture was quenched with 10 mL MeOH and concentrated. The concentrate was diluted again with 5 mL of MeOH, and 20 mL of MeOH was added. The resultant solid was filtered, collected, and dried under vacuum overnight to give 0.012 g (29% yield) of SA-52 as a brown solid. 1 H NMR (200 MHz, CDCl 3 ) 6 HRMS calculated for C 13 H 11 BrNO 5 (M+H) + 339.9821. found 339.9828.
Example 2
Synthesis of SA-53
[0092]
[0093] To 0.401 g (1.5 mmol) of 2-bromo-4,5-dimethoxybenzoic acid (3) in 4 mL of DCM was added 0.4 mL (4.7 mmol) of oxalyl chloride, and 1 drop of DMF. The mixture was stirred for 7 h, concentrated, dried in vacuo in a similar manner to compound 2, and diluted with 5 mL of DCM. This solution was cooled to −78° C., treated with 0.8 mL pyridine and 0.137 (1 mmol) 3,4-methylenedioxy aniline. The mixture was then brought to 23° C., stirred 16 h, quenched with 10 mL of water, and the resultant layers separated. The organic layer was washed twice with 10 mL of water, dried with Na 2 SO 4 , and concentrated. The crude product was purified by PTLC using 10% EtOAc in DCM as the eluent to give 0.310 g (82% yield) of benzamide 4 as a brown solid. NMR (200 MHz, CDCl 3 ) δ 7.90 (bs, 1H), 7.40 (bs, 1H), 7.27 (d, J=2.6 Hz, 1H), 7.15 (s, 1H), 6.96 (d, J=8.6 Hz, 1H), 6.81 (d, J=8.6 Hz, 1H), 6.00 (s, 2H), 3.93 (s, 6H), HRMS calculated for C 16 H 15 BrNO 5 (M+H) + 380.0134. found 380.0145.
Example 3
Synthesis of SA-54
[0094]
[0095] To 0.230 g (0.58 mmol) of benzamide 2 was added 0.017 g of CuI (0.09 mmol), 0.031 g (0.17 mmol) of 1,10 phenanthroline, and 0.560 g (1.7 mmol) of Cs 2 CO 3 . The mixture was suspended in 5 mL of diglyme, and heated to 140° C. for 20 h. The mixture was diluted with 30 mL DCM, washed three times with 20 mL of water, dried (Na 2 SO 4 ), and concentrated to give an orange oil as the crude product. This was heated under vacuum (1 mm Hg) until a light orange solid formed to give 0.135 g (75% yield) of benzoxazole 5, which was used without further purification. NMR (200 MHz, CDCl 3 ) δ 7.74 (dd, J=2.0 Hz, 8.4 Hz, 1H), 7.67 (d, J=2.2 Hz, 1H), 7.21 (s, 3H), 7.10 (s, 3H), 6.95 (d, J=8.4 Hz, 1H), 3.98-3.89 (4 overlapping singlets, 12H).
[0096] To 0.071 g (0.23 mmol) of 5 in 5 mL of DCM at 0° C. was added 2 mL 1M BBr 3 in DCM. The dark brown mixture was stirred 6 h, quenched with 5 mL MeOH, and concentrated. The MeOH dilution-concentration procedure was repeated three more times to give 0.081 g of crude product. This product was purified by PTLC using 5% MeOH/DCM followed by 10% MeOH/DCM as the eluent and gave 0.023 g (39% yield) of SA-54 as an off-white solid. 1 H NMR (200 MHz) δ□8.84 (bs, 2H), 8.34 (bs, 1H), 7.35 (bs, 1H), 7.47 (d, J=2 Hz, 1H), 7.40 (dd, J=2 Hz, 8.2 Hz, 1H), 7.05 (s, 2H), 7.01 (s, 2H). HRMS Calculated for C 13 H 10 NO 5 (M+H) + 260.0586. found 260.0559.
Example 4
Synthesis of SA-55
[0097]
[0098] To 10.00 g (51 mmol) of methyl 3,4 dimethoxybenzoate (6) in 50 mL of AcOH at 0° C. was added 8.90 g (56 mmol) of Br 2 in 50 mL of AcOH over 1.5 h. The ice bath was removed and the mixture stirred 45 min. The reaction was quenched by pouring into 700 mL of H 2 O, stirred 30 min, left quiescent for 1 h, and filtered. The collected solid was washed with H 2 O and washed with sat. aq. Na 2 S 2 O 3 . The solid was partially dried, dissolved in 300 mL hot MeOH, and the resultant solution was cooled. The cool methanolic solution of product was treated with 200 mL of H 2 O and the white solid filtered to give 8.92 g (64% yield) of methyl-2-bromo-4,5-dimethoxybenzoate (7) as a white powder. The compound matched the physical and spectral properties of the known compound.
[0099] A mixture of 0.960 g (3.48 mmol) of 7, 1.60 g (35 mmol) of hydrazine hydrate (62% hydrazine), and 5 mL of EtOH was refluxed for 15 h. The mixture was cooled to −20° C., vacuum filtered, washed with 50 mL of ice-cold 1:1 EtOH:H 2 O, and dried to give 0.832 g (87% yield) of (2-bromo-4,5-dimethoxy benzoyloxy) hydrazine (8) as a white, needle-like crystalline solid. The above procedure was repeated on 2.79 g of the starting ester 7 to result in 2.77 g (99% yield) of 8. 1 H NMR (200 MHz, CDCl 3 ) δ 6.97 (s, 1H), 6.86 (s, 1H), 3.85 (s, 6H). HRMS Calculated for C 9 H 12 O 3 N 2 Br 275.0031. found 275.0037.
[0100] To 2.15 g (11.8 mmol) of 3,4-dimethoxybenzoic acid (1) in 10 mL of DCM was added sequentially 2.5 mL (29.1 mmol) oxalyl chloride and 0.2 mL of DMF. The mixture was stirred for 16 h during which time it became a clear, light yellow solution. This solution was concentrated and dried thoroughly to remove the excess oxalyl chloride to generate the crude acid chloride as a light yellow solid. This solid was taken up in 20 mL of DCM, the solution cooled to 0° C., and treated with 10 mL of pyridine and 0.25 g of DMAP. The resultant solution was treated with 1.69 g (6.15 mmol) of 8 in 10 mL DCM and 10 mL of pyridine. The mixture was stirred 3 h at 0° C. and warmed to 23° C. The reaction was stirred an additional 16 h, concentrated, taken up in 50 mL of EtOAc, and the layers separated. The aqueous was extracted once more with 50 mL EtOAc. The combined organic layers were washed three times with 100 mL H 2 O, dried (Na 2 SO 4 ), and concentrated. The concentrate was purified by Flash 40+M column chromatography (Biotage) eluting first with 150 mL of 1:1 EtOAc/Hex and then 2 L 5:1 EtOAc/Hex to give 1.27 g (47% yield) of hydrazide 9 as a yellow-brown powder. The reaction was repeated using 2.20 g of 3,4 dihydroxybenzoic acid (1) and 2.77 g of hydrazine 8 to give 2.60 g (49% yield) of hydrazide 9. 1 H NMR (200 MHz, CDCl 3 ) δ 9.91 (d, J=5.2 Hz, 1H), 9.53 (d, J=5.0 Hz, 1H), 7.46 (dd, J=2.0 Hz, 8.4 Hz, 1H), 7.41 (d, J=2.2 Hz, 1H), 7.23 (s, 1H), 6.98 (s, 1H), 6.80 (d, J 8.4 Hz, 1H), 3.96-3.89 (4 overlapping singlets, 12H).
[0101] A solution of 0.352 g of intermediate 9 in 3 mL of POCl 3 was refluxed for 3 h. The reaction mixture is cooled, poured into 125 mL of water, and sonicated for one minute. The suspension was allowed to stand for 1 h, and the solid was filtered, washed with excess water, collected, and air-dried to give 0.302 g (90% yield) of brominated tetramethoxyoxadiazole (10) as a white solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.71 (dd, J 2.0 Hz, 8.4 Hz, 1H), 7.67 (d, J=2.0 Hz, 1H), 7.57 (s, 1H), 7.17 (s, 1H), 6.98 (d, J=8.2 Hz, 1H), 3.96 (4 overlapping singlets, 12H). HRMS Calculated for C 14 H 10 BrN 2 O 5 (M+H) + 421.0339. found 421.0334.
[0102] A mixture of 0.038 g of intermediate 10 in 3 mL of DCM was cooled to −78° C., and treated dropwise with a solution of 0.450 g of BBr 3 in 5 mL of DCM. The mixture was stirred at −78° C. for 1 h, then at 23° C. for 2.5 h. The mixture was quenched by adding it carefully to 5 mL of MeOH in a 100 mL flask. The methanol solution was concentrated to 1 mL, diluted with 5 mL water, and filtered to give 0.017 g (56% yield) of SA-55 as a light yellow solid. 1 H NMR (200 MHz, CDCl 3 ) δ 10.5-9.5 (overlapping broad singlets, 4H), 7.56 (d, J=2 Hz, 1H), 7.52 (s, 1H), 7.48 (dd, J=2 Hz, 8.6 Hz, 1H), 7.25 (s, 1H), 7.04 (d, J=8.4 Hz, 1H)
Example 5
Synthesis of SA-57
[0103]
[0104] To a thick-walled 15 mL tube with a resealable Teflon screw-cap was added 0.584 g (4.32 mmol) of 3,4-dihydroxybenzonitrile (12), 5 mL of triethylene glycol, 1.172 g of NaSH.xH 2 O, and 0.25 mL of concentrated H 2 SO 4 . The tube was sealed with the cap, and the mixture was warmed to 110° C. and stirred for 3 days at this temperature. The reaction was quenched by pouring into 100 mL sat. aq. NH 4 + Cl, and extracted twice with 50 mL of EtOAc. The combined organics were washed three times with 15 mL water, dried with NaSO 4 , and concentrated to give 0.512 g (71% yield) of 13 as a golden colored solid. 1 H NMR (200 MHz, CDCl 3 ) δ 9.67 (s, 1H), 9.29 (s, 1H), 7.56 (dd, J 1.8 Hz, 8.2 Hz), 7.49 (d, J=1.8 Hz), 6.94 (d, J=8.2 Hz), 6.09 (s, 2H). 13 C NMR (50 MHz, CDCl 3 ) δ 198.9, 150.5, 147.4, 133.7, 123.3, 108.2, 107.8, 102.3.
[0105] A solution of 0.40 g (2.37 mmol) of 13 in 7 mL of DMSO was treated with 12 drops of concentrated HCl, warmed to 38° C. for 18 h, and poured into 25 mL of brine. The resultant solid was filtered and washed with water to give 0.21 g (59% yield) of SA-57 as a yellow solid. 1 H-NMR (DMSO-d6) 9.85 (bs, 1H) 9.52 (bs, 1H), 9.43 (bs, 1H), 9.28 (bs, 1H), 7.69 (d, 1H, J=2 Hz), 7.59 (dd, 1H, J=2.2, 8.2 Hz), 7.46 (d, 1H, J=2 Hz), 7.38 (dd, 1H, J=2.2, 8.2 Hz), 6.90 (d, 1H, J=8.2 Hz), 6.86 (d, 1H, J=8.4 Hz). 13 C-NMR (DMSO-d6) 187.8, 173.4, 150.2, 148.5, 146.4, 145.9, 124.6, 122.0, 120.4, 120.2, 116.8, 116.2, 115.7, 114.5. HRMS-ESI Calculated for C 14 H 11 N 2 O 4 S (M±H) + 303.0440. found 303.0448.
Example 6
Synthesis of SA-58
[0106]
[0107] To a solution of 2,5-dibromothiophene (14) (242 mg, 1 mmol), (3,4-dimethoxy phenyl)boronic acid (15) (455 mg, 2.5 mmol), and Pd(PPh 3 ) 4 (58 mg, 0.05 mmol) in dioxane (10 mL) was added Na 2 CO 3 (12 mL, 2.0 M aqueous solution). The resultant mixture was purged with nitrogen and stirred rapidly while heating at 90° C. overnight. The reaction mixture was cooled to 23° C., acidified with 1M HCl and extracted with EtOAc. The combined organic extracts were washed with H 2 O, dried over MgSO 4 , filtered and concentrated under reduced pressure. 2,5-bis(3′,4′-dimethoxyphenyl)thiophene (16) was obtained quantitatively as a green-yellow solid after the purification by column chromatography (10%-20% EtOAc in hexanes).
[0108] To a solution of 2,5-bis(3′,4′-dimethoxyphenyl)thiophene 16 (110 mg, 0.3 mmol) in dry dichloromethane at −78° C. was added BBr 3 (3 mL, 1M solution in DCM, 2.5 equiv per methoxy function) dropwise. The reaction mixture was stirred at −78° C. for 3 h, warmed to 23° C., and stirred 16 h under nitrogen atmosphere. Water (10 mL) was added to quench the reaction, and the aqueous layer was extracted with EtOAc. The combined organic layer was washed with brine, dried over MgSO 4 , filtered, and concentrated under reduced pressure. The product was purified by recrystallization in MeOH/DCM and SA-58 was obtained quantitatively as a greenish solid.
Example 7
Synthesis of SA-59, SA-60 and SA-61
[0109]
[0110] 3-bromo-2,5-bis(3′,4′-dimethoxyphenyl)thiophene (18) was prepared by the reaction of 2,3,5-tribromothiophene (17) (321 mg, 1 mmol) and (3,4-dimethoxyphenyl)boronic acid (15) (419 mg, 2.3 mmol) according to the similar procedure for compound 16. The reaction mixture was purified by column chromatography (10%-30% EtOAc in hexanes) and afforded 18 (337 mg, 77% yield) as a yellow solid. SA-60 was also isolated (97 mg, 20% yield) from the reaction above as a dark yellow solid.
[0111] SA-59 was prepared by the reaction of 3-bromo-2,5-bis(3′,4′-dimethoxyphenyl)thiophene (18) (258 mg, 0.59 mmol) and BBr 3 (6 mL, 6 mmol) according to the similar procedure for compound SA-58. SA-59 (157 mg, 70% yield) was obtained after preparative thin layer chromatography (PTLC) purification (10% MeOH in DCM) as a green solid.
[0112] SA-61 was prepared by the reaction of 2,3,5-tri(3′,4′-dimethoxyphenyl)thiophene (SA-60) (68 mg, 0.14 mmol) and BBr 3 (2 mL, 2 mmol) according to the similar procedure for compound SA-58. SA-61 (34 mg, 60% yield) was obtained after PTLC purification (10% MeOH in DCM) as a brown oil.
Example 8
Synthesis of SA-62
[0113]
[0114] Compound 19 was prepared by the reaction of 2,5-dibromothiophene (17) (1.14 g, 5.24 mmol) and (3,4-dimethoxyphenyl) boronic acid (15) (910 mg, 5 mmol) according to the similar procedure for compound 16. The reaction mixture was purified by flash column chromatography (FCC) (5%-20% EtOAc in hexanes) and afforded compound 19 (509 mg, 34% yield) as a yellowish crystal. Compound 16 was also isolated (578 mg, 65% yield) as a yellow solid.
[0115] SA-62 was prepared by the reaction of 2-bromo-5-(3,4-dimethoxyphenyl)thiophene (19) (60 mg, 0.2 mmol) and BBr 3 (1M in DCM, 1 mL, 1 mmol) according to the similar procedure for compound SA-52 and isolated as a green solid in quantitative yield.
Example 9
Synthesis of SA-63
[0116]
[0117] Compound 21 was prepared by the reaction of 2-bromo-5-(3,4-dimethoxyphenyl)thiophene (19) (449 mg, 1.5 mmol) and (3,4,5-trimethoxyphenyl)boronic acid (20) (382 mg, 1.8 mmol) according to the similar procedure for compound 16 and purified by column chromatography (10%-20% EtOAc in hexanes), then recrystallization (EtOAc) provided the desired compound as a yellow solid (524 mg, 91% yield).
[0118] SA-63 was prepared by the reaction of 2-(3,4-dimethoxyphenyl)-5-(3,4,5-trimethoxyphenyl)thiophene (21) (47 mg, 0.12 mmol) and BBr 3 (1M in DCM, 0.8 mL, 0.8 mmol) according to the similar procedure for compound SA-52. SA-63 was obtained quantitatively as dark blue solid.
Example 10
Synthesis of SA-64
[0119]
[0120] To a solution of dioxane/EtOH/H 2 O (6 mL, 1/1/1) in a microwave reaction vial (Biotage) was added 2,5-dibromothiazole (22) (122 mg, 0.5 mmol), (3,4-dimethoxyphenyl)boronic acid (15) (218 mg, 1.2 mmol), Pd(PPh 3 ) 4 (29 mg, 0.025 mmol) and Cs 2 CO 3 (0.72 g, 2.2 mmol). The mixture was purged with nitrogen and heated in a microwave reactor (Biotage) to 160° C. for 1 h. The reaction mixture was cooled to 23° C., acidified with 1M HCl until the pH was 1, and extracted with. EtOAc. The combined organic extracts were washed with H 2 O before being dried over MgSO 4 , filtered, and concentrated under reduced pressure. Compound 24 was purified by column chromatography (5%-35% EtOAc in hexanes) as brown-yellow solid (28 mg, 16% yield). 5-bromo-2-(3,4-dimethoxyphenyl)thiazole (23) was also isolated from the reaction above as brown-yellow crystalline solid (28 mg, 19% yield).
[0121] SA-64 was prepared by the reaction of 2,5-bis(3,4-dimethoxyphenyl)thiazole (24) (28 mg, 0.078 mmol) and BBr 3 (1M in DCM, 0.75 mL, 0.75 mmol) according to the similar procedure for compound SA-58, and was obtained as a yellow solid (14 mg, 60% yield).
Example 11
Synthesis of SA-65
[0122] A mixture of 0.100 g (0.237 mmol) of 10, 0.600 g (1.03 mmol) of hexabutylditin, 5 mL of PhMe, and 1 mL of TEA was degassed by nitrogen purge. Then 0.050 g of Pd(PPh 3 ) 4 was added. The reaction mixture was refluxed for 16 h. At this time, the reaction was incomplete, but a decomposition product was seen in addition to the desired product. The reaction was at this point concentrated and purified by PTLC to prevent further decomposition to give 0.090 g (60% yield) of SA-65 as an off-white solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.68-7.65 (overlapping peak doublet and doublet of doublets, 2H), 7.53 (s, 1H), 7.16 (s, 1H), 6.98 (d, J=9.0 Hz, 1H), 3.99-3.96 (4 overlapping singlets, 12H), 1.55 (m, 6H), 1.44 (m, 6H), 1.15 (m, 6H), 0.84 (t, J=7.2 Hz, 9H).
Example 12
Synthesis of SA-66
[0123]
[0124] A mixture of 0.174 g of Lawesson's reagent, 0.175 g of compound 9, and 20 mL of PhMe was heated to 60° C. for 3 h. The mixture was concentrated, and applied directly to a PTLC plate for purification. The brominated thiadiazole 11 was purified by PTLC and the middle of the desired product spot (fluoresces blue under UV light) was collected to give 0.112 g (65% yield) of compound 11 as an off-white to brown solid.
[0125] The above experiment was repeated using 1.13 g of 9, 1.21 g of Lawesson's reagent, and 200 mL of PhMe. The mixture was refluxed 3 h, and quenched with 150 mL of water. The layers were separated, and the aqueous extracted twice with 30 mL of EtOAc. The organic layers were combined and washed twice with 50 mL 1 N aq. HCl, twice with 50 mL saturated aq. NaHCO 3 , once with 25 mL of water, and once with 50 mL of brine. The organic was dried, concentrated, and purified by PTLC to give 1.04 g of the desired 11 as a yellow solid (97% yield). 1 H NMR (200 MHz, CDCl 3 ) δ 7.88 (s, 1H), 7.68 (bs, 1H), 7.51 (d, J=7.8 Hz, 1H), 7.15 (s, 1H), 6.95 (d, J=8.4 Hz, 1H), 4.00-3.95 (4 overlapping singlets, 12H).
[0126] A solution of 0.051 g of 11 in 5 mL DCM was cooled to −78° C., treated with 1.5 mL of 2 M BBr 3 in DCM, stirred at −78° C. for 0.5 h, and stirred at 23° C. for 3 h. The mixture was quenched with water carefully, poured into 100 mL brine, and extracted twice with 75 mL of EtOAc. The combined organic layers were dried and concentrated to yield 36 mg (81% yield) of the crude title compound as a yellow solid. The mixture was recrystallized from hot MeOH and precipitated with water to give 0.021 g (50% yield) of SA-66 as a brown solid.
[0127] The above experiment was repeated on 0.077 g of starting material using the same procedure with the exception of slightly different stirring times (1 h at −78° C., 4 h at 23° C.) to give 0.054 g (83% yield) of SA-66. 1 H NMR (200 MHz, DMSO-d 6 ) δ 10.10 (s, 1H), 9.78 (s, 1H), 9.68 (s, 1H), 9.47 (s, 1H), 7.55 (s, 1H), 7.43 (d, J=1.8 Hz, 1H), 7.29 (dd, J=1.8 Hz, 8.0 Hz, 1H), 7.13 (s, 1H), 6.87 (d, J=8.2 Hz, 1H).
Example 13
Synthesis of SA-67
[0128]
[0129] To 0.285 g (1.57 mmol) of 3,4 dimethoxybenzoic acid (1) in 5 mL of DCM was added 0.3 mL (3.5 mmol) of oxalyl chloride and one drop of DMF. The mixture was stirred for 2 h, quenched with hydrazine hydrate (3 mL), concentrated, and dried. The solid was taken up in 25 mL water, sonicated five minutes, filtered, and the resultant solid washed with 40 mL water. The solid was dried, taken up in 20:1 DCM:DMF, and purified by PTLC (8:2 EtOAc:Hexanes) to give 0.056 g (20% yield) of 25 as an off-white solid. 1 H NMR (200 MHz, DMSO-d 6 ) δ 10.30 (s, 2H), 7.58 (d, J 8.4 Hz, 1H), 7.51 (bs, 1H), 7.18 (d, J=8.4 Hz, 1H), 3.82 (bs, 12H).
[0130] To 0.050 g (0.14 mmol) of hydrazide 25 was added 3 mL of POCl 3 . The mixture was refluxed 2 h, quenched with 50 g of ice, allowed to warm to 23° C., and extracted twice with 25 mL of EtOAc. The organic layers were washed once with 25 mL water, twice with 25 mL of brine, dried with Na 2 SO 4 , and concentrated to give 0.043 g (93% yield) of 26 as a white solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.72 (d, J=8.0 Hz, 2H), 7.60 (d, J=1.2 Hz, 1H), 7.07 (d, J=8.4 Hz, 1H), 3.89 (s, 6H), 3.87 (s, 6H).
[0131] To 0,038 g (0.11 mmol) of oxadiazole 26 was added 3 mL of DCM. The solution was cooled to −78°, and 5 mL of DCM containing 0,450 g (1.8 mmol) of BBr 3 was added. The mixture was stirred at −78° C. for 1 h, at 23° C. for 2.5 h, quenched by pouring into 5 mL of MeOH, and concentrated to 1 mL. The resultant oil was diluted with 5 mL water and the resultant precipitate was filtered to give 0.017 g (56% yield) of SA-67 as a yellow solid. 1 H NMR (200 MHz, DMSO-d 6 ) δ 9.74 (bs, 2H), 9.51 (bs, 2H), 7.43 (d, J=2.0 Hz, 1H), 7.37 (dd, J=2.0 Hz, 8.4 Hz, 1H), 6.93 (d, J=8.0 Hz, 1H).
Example 14
Synthesis of SA-68
[0132]
[0133] 4-azido-1,2-dimethoxybenzene (27) (62 mg, 0.31 mmol), 4-ethynyl-1,2-dimethoxy benzene (28) (52 mg, 0.31 mmol), sodium ascorbate (0.25 mL of 1M solution, 0.25 mmol), CuSO 4 (0.020 mL of 1M solution, 0.020 mmol) and tBuOH/H 2 O (2 mL, 1/1) were added to a vial. The reaction mixture was purged with nitrogen, stirred at 23° C. overnight, poured into water at 0° C., and the resultant brown solid was filtered. This solid was washed with water (1 mL) and Et 2 O (1 mL). Compound 29 (99 mg, 93% yield) was used in the next step without further purification.
[0134] SA-68 was prepared by the reaction of 1,4-bis(3,4-dimethoxyphenyl)-1H-1,2,3-triazole (29) (67 mg, 0.20 mmol) and BBr 3 (1M in DCM, 0.79 mL, 0.79 mmol) according to the similar procedure for compound SA-52. SA-68 was obtained as a dark brown solid (56 mg, 98% yield).
Example 15
Synthesis of SA-69
[0135]
[0136] To a solution of dioxane/EtOH/H 2 O (6 mL, 1/1/1) were added 2,5-dibromothiazole (22) (756 mg, 3.1 mmol), (3,4-dimethoxyphenyl)boronic acid (15) (380 mg, 2.1 mmol), Pd(PPh 3 ) 4 (58 mg, 0.05 mmol) and Cs 2 CO 3 (1.4 g, 4.4 mmol) in a 20 mL microwave reaction vial (Biotage). The solution was purged with nitrogen and heated in a microwave reactor (Biotage) to 160° C. for 30 min. The reaction mixture was cooled to 23° C., acidified with 1M HCl until pH=1, and extracted with EtOAc. The combined organic extracts were washed with H 2 O before being dried over MgSO 4 , filtered, and concentrated under reduced pressure. Compound 23 was purified by flash column chromatography (8%-50% EtOAc in hexanes) as brown-yellow solid (193 mg, 32% yield). 2,5-bis(3,4-dimethoxyphenyl)thiazole (24), was also isolated as a brown-yellow solid (34 mg, 5% yield).
[0137] SA-69 was prepared by the reaction of 5-bromo-2-(3′,4′-dimethoxyphenyl)thiazole (23) (78 mg, 0.26 mmol) and BBr 3 (1M in DCM, 0.65 mL, 0.65 mmol) according to the similar procedure for compound SA-52, and was obtained as a brown-yellow solid quantitatively.
Example 16
Synthesis of SA-70
[0138]
[0139] A mixture of 0.996 g (6 mmol) 3,4-dimethoxybenzaldehyde (30), 1.25 g of TosMIC (6.4 mmol), and 0.923 g (6.6 mmol) of K 2 CO 3 was refluxed in 30 mL of MeOH for 3 h. The reaction mixture was quenched by pouring into 200 mL of a 1:1 mixture of brine and water, cooled to −20° C. for 1 h, and the resultant solid filtered to give 0.952 g (77% yield) of 31 as an off-white solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.85 (s, 1H), 7.22 (s, 1H), 7.20 (overlapping peak, 1H), 7.15 (dd, J=2.0 Hz, 12.4 Hz, 1H), 6.88 (d, J=1H), 3.91 (s, 3H), 3.88 (s, 3H).
[0140] A suspension of 0.212 g of Na 2 CO 3 (2 mmol), 0,262 g of PPh 3 (1 mmol), 0.206 g (1 mmol) of 31 and 0.316 g of 4-iodoveratrole (1.2 mmol) was formed in 1 mL of DMF. Then, 0.190 g (1 mmol) of CuI was added. The mixture was stirred at 160° C. for 3 h and quenched by pouring into 50 mL of water containing 5% NH 4 + OH − . The product was extracted with 50 mL DCM, the organic layer dried and concentrated, and the crude product purified by PTLC to give 0.174 g (51% yield) of 32 as a yellow solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.60 (d, J=8.4 Hz, 1H), 7.54, (bs, 1H), 7.24 (s, 1H), 7.19 (bs, 1H), 7.10 (s, 1H), 6.90-6.83 (m, 2H), 3.91-3.86 (4 overlapping multiplets, 12H). 13 C NMR (50 MHz, CDCl 3 ) δ 160.7, 150.9, 149.3, 149.2, 132.1, 132.0, 122.0, 121.2, 120.4, 119.3, 117.1, 111.5, 111.1, 109.1, 107.5, 56.01, 55.92.
[0141] A mixture of 0.075 g (0.22 mmol) of 32 in 15 mL DCM was treated with 0.500 g (2 mmol) of BBr 3 at −78° C. The mixture was stirred at −78° C. for 0.5 h, then 2 h at 23° C. The reaction was then quenched with 5 mL MeOH, concentrated to 1 mmol and diluted with 5 mL of water. The resultant precipitate was filtered to give 0.021 g (33% yield) of SA-70 as a yellow solid. 1 H NMR (200 MHz, DMSO-d 6 ) δ 7.40 (s, 2H), 7.31 (dd, J=2.0 Hz, 8.0 Hz, 1H), 7.13 (d, J=2.2 Hz), 7.05 (dd, J=2.2 Hz, 8.2 Hz, 1H), 6.86 (d, J=7.8 Hz, 1H), 6.82 (d, J=7.8 Hz, 1H). HRMS Calculated for C 15 H 12 NO 5 (M+H) + 286.0715. found 286.0717.
Example 17
Synthesis of SA-72
[0142]
[0143] A solution of 0.115 g (0.32 mmol) of 25 in 30 mL of PhMe was treated with 0.140 g of Lawesson's reagent (0.35 mmol) and stirred 3 h at 100° C. The reaction mixture was poured into 75 mL water, shaken vigorously, and extracted with 50 mL EtOAc. The organic layers were combined, washed with 25 ml saturated aqueous NaHCO 3 , washed with 50 mL brine, dried, and concentrated. The crude product was purified by PTLC to give 0.088 g (74% yield) of 33 as a yellow solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.60 (bs, 2H), 7.37 (d, J=8.2 Hz, 2H), 6.86 (d, J=8.4 Hz, 2H), 3.95 (s, 6H), 3.90 (s, 6H). 13 C NMR (200 MHz, CDCl 3 ) 167.3, 151.6, 149.4, 123.2, 121.6, 111.2, 110.0, 56.1, 56.0. HRMS Calculated for C 16 H 19 N 2 O 4 S (M+H) 359.1066. found 359.1061.
[0144] A solution of 0.077 g (0.22 mmol) of 33 and 3 mL DCM was treated with 0.250 g BBr 3 at −78° C. The reaction mixture was stirred 1 h, treated with 0.250 g BBr 3 , and stirred an addition 15 min at −78° C. The mixture was warmed to 23° C., stirred for 1 h, quenched with 10 mL MeOH, and concentrated. The concentrate was taken up in 1 mL MeOH, warmed until a solution, and precipitated with 10 mL water. The resultant solid was filtered and dried to give 0.054 g of SA-72 (83% yield) as an off-white solid. 1 H NMR (200 MHz, DMSO-d 6 ) 10.0-9.0 (broad peak, 4H), 7.41 (d, J=2.2 Hz, 2H), 7.24 (dd, J=2.2 Hz, 8.2 Hz, 1H), 6.87 (d, J=8.2 Hz, 2H).
Example 18
Synthesis of SA-74
[0145]
[0146] To a mixture of 0.219 g (0.5 mmol) of 11 in 20 mL PhMe was added 1.09 g (Bu 3 Sn) 2 and 2 mL of triethylamine. The mixture was degassed via a nitrogen purge, treated with 0.150 g (0.13 mmol) of Pd(PPh 3 ) 4 , and refluxed for 15 h. The mixture was concentrated and purified directly by PTLC by eluting the plates with 1% TEA in hexanes then 50% EtOAc in hexanes with 1% TEA successively. This gave 0.224 g (69% yield) SA-74 as an off-white solid.
Example 19
Synthesis of SA-75 and SA-76
[0147]
[0148] A solution of 0.051 g of SA-74 in 3 mL of DCM was treated with a 1 M iodine in DCM solution until the orange/yellow color of the iodine persists. The mixture was quenched with a 1 M solution of KF in MeOH (2 mL) then sat. aq. Na 2 S 2 O 3 (2 mL). The mixture was extracted twice with 10 mL EtOAc. The organic layers were combined, washed with 10 mL water, dried and concentrated to give the crude title compound. The crude product was purified by PTLC with another run of this reaction using 0.082 g of SA-74 and run in the same manner as described above. This gave 0.012 g (12% yield) of SA-75 as a yellow solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.73 (d, J=2.2 Hz, 1H), 7.59 (s, 1H), 7.54 (dd, J=2.2 Hz, 8.4 Hz), 7.42 (s, 1H), 6.98 (d, J=8.4 Hz, 1H), 4.03-3.95 (4 overlapping singlets, 12H).
[0149] A solution of 0.008 g of SA-75 in 1 mL of DCM was cooled to 0° C., treated with 0.5 mL of 1 M BBr 3 in DCM, and stirred for 1 h. The reaction was treated with an additional 1 mL portion of 1 M BBr 3 in DCM, stirred an additional 2 h at 0° C., and warmed to 23° C. The reaction mixture was stirred an additional 0.5 h, quenched with 3 mL MeOH, and concentrated to 0.5 mL. The product was precipitated with 5 mL water, and the resultant yellow solid was filtered and dried to give (0.002 g) of SA-76 as a yellow-green solid. 1 H NMR (200 MHz, DMSO-d 6 ) δ 9.93-9.50 (overlapping broad singlets, 4H), 7.42-7.28 (overlapping irresolvable peaks, 4H), 6.98 (d, J=8.2 Hz, 1H).
Example 20
Synthesis of SA-77 and SA-78
[0150]
[0151] To a round-bottom flask charged with 5-(5-(3,4-dihydroxyphenyl)thiophen-2-yl)benzene-1,2,3-triol (SA-63) (145 mg, 0.46 mmol), 4-methylbenzenesulfonic acid (p-TsOH.H 2 O) (8.7 mg, 0.046 mmol), and 2,2-dimethoxypropane (0.45 mL, 3.7 mmol) were added acetone (3 mL) and benzene (15 mL). A short column with 4 Å molecular sieves and a condenser were installed on the flask. The reaction was refluxed for 15 h. An additional portion of 2,2-dimethoxypropane (0.45 mL, 3.7 mmol) was added, and the reaction was refluxed for another 24 h. The solution was concentrated at reduced pressure and purified by PTLC, which afforded 34 as a white solid (53 mg, 29%).
[0152] To a solution of 6-(5-(2,2-dimethylbenzo[d][1,3]dioxol-5-yl)thiophen-2-yl)-2,2-dimethylbenzo[d][1,3]dioxol-4-ol (34) (53 mg, 0.13 mmol), triethylamine (0.056 mL, 0.40 mmol) and DCM (2 mL) was added trifluoromethanesulfonic anhydride (0.034 mL, 0.20 mmol) at 0° C. The reaction was warmed to 23° C. after 30 min and extracted with DCM. The organic layer was washed with sat. aq. NaHCO 3 , H 2 O and brine. The organic layers were dried over MgSO 4 , concentrated, and 35 was obtained as yellowish oil (53 mg, 75% yield).
[0153] To 6-(5-(2,2-dimethylbenzo[d][1,3]dioxol-5-yl)thiophen-2-yl)-2,2-dimethylbenzo[d][1,3]dioxol-4-yltrifluoromethanesulfonate (35) (32 mg, 0.061 mmol) was added Pd(PPh 3 ) 4 (14 mg, 0.012 mmol), LiCl (26 mg, 0.61 mmol), bistributylditin (0.153 mL, 0.305 mmol) and dioxane (2 mL) (plus Triethythylamine??). The solution was purged with nitrogen and refluxed for 3.5 h. The reaction was concentrated, evaporated and subjected to PTLC (8% EtOAc in hexanes). SA-77 was obtained as a yellowish oil (26 mg, 64% yield).
[0000]
[0154] To the solution of tributyl(6-(5-(2,2-dimethylbenzo[d][1,3]dioxol-5-yl)thiophen-2-yl)-2,2-dimethylbenzo[d][1,3]dioxol-4-yl)stannane (SA-77) (26 mg, 0.039 mmol) and THF (1 mL) was added the solution of I 2 (20 mg, 0.078 mmol) in THF (1 mL) dropwise. The reaction was stirred for 10 min and concentrated, and 36 was obtained quantitatively as a yellow solid after purification by PTLC (7% EtOAc in hexanes).
[0155] To 6-(5-(2,2-dimethylbenzo[d][1,3]dioxol-5-yl)thiophen-2-yl)-4-iodo-2,2-dimethylbenzo[d][1,3]dioxole (36) (15 mg, 0.029 mmol) were added a few drops of H 2 O and trifluoroacetic acid (0.45 mL). The reaction was stirred at 23° C. for 1 h, and afforded SA-78 quantitatively as a white crystal after concentration at reduced pressure.
Example 21
Synthesis of SA-79 and 80
[0156]
[0157] To 4-(5-bromothiazol-2-yl)benzene-1,2-diol (SA-69) (90 mg, 0.32 mmol) was added 4-dimethylaminopyridine (DMAP) (117 mg) and acetic anhydride (3 mL). The reaction was stirred at 23° C. for 1 h before it was extracted with EtOAc. The organic layer was washed with sat. aq. NaHCO 3 , H 2 O and brine and dried over MgSO 4 . SA-79 was obtained as yellow solid (74 mg, 65% yield) after PTLC (20% EtOAc in hexanes).
[0158] To a solution of 4-(5-bromothiazol-2-yl)-1,2-phenylene diacetate (SA-79) (36 mg, 0.10 mmol), Pd(PPh 3 ) 4 and dioxane (2 mL) was added bistributyltin (0.25 mL, 0.50 mmol). The solution was purged with nitrogen and refluxed for 1.5 h. PTLC (25% EtOAc in hexanes) provided SA-80 as yellow oil (22 mg, 39% yield).
Example 22
Synthesis of SA-81
[0159]
[0160] To a solution of nBuLi (0.34 mL, 2.5 M in hexanes) and THF (6 mL) was added 5-bromo-2-(3,4-dimethoxyphenyl)thiazole (23) (54 mg, 0.18 mmol) and additional THF (3 mL) was added dropwise at −78° C. under nitrogen atmosphere. SnBu 3 Cl (0.15 mL) was added after the reaction was stirred at −78° C. for 30 min. After another 30 min, saturated aqueous NaHCO 3 was added to quench the reaction. The mixture was extracted with EtOAc and the organic layer was washed with water and brine. PTLC (25% EtOAc in hexanes) provided SA-81 as a yellow oil (58 mg, 63% yield).
Example 23
Synthesis of SA-82
[0161]
[0162] A mixture of 0.26 g (1 mmol) of 2-bromo-4,5-dimethoxybenzoic acid (3) in 5 mL of DCM was treated with 0.3 mL of (COCl) 2 and two drops of DMF. The mixture was stirred for an additional hour after a yellow solution had formed (about 2 h total). The mixture was concentrated and dried in vacuo thoroughly, taken up in 15 mL of DCM, cooled to 0° C., and treated with 2 mL pyridine. Then 0.79 g of known amine 37 was added. The mixture was warmed to 23° C., stirred 3 days, and quenched with water. The product was extracted with 10 mL of DCM, the combined organic was washed with 10 mL water, dried, and concentrated to give the crude product that was purified by PTLC (50% EtOAc in hexanes) to give 0.070 g (16% yield) of compound 38 as a light brown solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.67 (dd, J=2.0 Hz, 8.4 Hz, 1H), 7.56 (apparent broad singlet, overlapping peaks, 2H), 7.04 (s, 1H), 6.95 (d, J=6.95 Hz, 1H), 4.94 (d, J=4.2 Hz, 1H), 3.98 (s, 3H), 3.95 (s, 3H), 3.86 (bs, 6H). HRMS Calculated for C 19 H 22 O 6 NBr (M+H) + 438.0552. found 438.0556.
[0163] A mixture of 0.103 g (0.24 mmol) of amide 38 in 10 mL of THF was treated with 0.117 g (0.29 mmol) of Lawesson's reagent. The mixture was refluxed for 2 h, cooled, and concentrated. The crude product was purified directly by PLTC to give 0.048 g (45% yield) of compound 39 as a light brown solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.78 (apparent singlet, 1H), 7.55-7.50 (overlapping singlet, dd, 2H), 7.46 (s, 1H), 7.13 (s, 1H), 6.94 (d, J=8.8 Hz, 1 h), 3.97-3.89 (overlapping singlets, 12H).
[0164] A solution of 0.031 g 39 (0.07 mmol) in 4 mL of DCM was cooled to −78° C., and treated with 1.5 mL of 1 M BBr 3 in DCM. The mixture was stirred for 1 h at −78° C., 1 h at 23° C., and quenched with 2 mL of MeOH. The mixture was concentrated to 1 mL, diluted with 10 mL water, sonicated, and the resultant solid filtered to give 0.009 g (35% yield) of SA-82 as an off-white solid.
Example 24
Synthesis of SA-83
[0165]
[0166] To 0.012 g (0.03 mmol) of SA-76 in 0.5 mL pyridine was added 0.05 mL of acetic anhydride. The mixture was stirred at 140° C. for 3 h, cooled, and poured into 10 mL of water with 0.5 g NH 4 + Cl − , and the product was extracted with 5 mL 10% MeOH in DCM. The extract was concentrated, and purified by PTLC to give 0.005 g (8.3*10 −3 mmol) of SA-83 as a brown oil. 1 H NMR (200 MHz, CDCl 3 ) δ 7.94-7.88 (3 overlapping irresolvable peaks, 3H), 7.82 (s, 1H), 7.36 (d, J=9.0 Hz), 2.34-2.32 (4 overlapping singlets, 12H).
Example 25
Synthesis of SA-84
[0167]
[0168] A mixture of 0.058 g (0.132 mmol) of amide 38 was refluxed in 2 mL POCl 3 . The solution was added to 50 mL of water and sonicated to precipitate a light yellow solid, which was filtered, washed with cold water, and dried to give 0.041 g (74% yield) of 40 as a yellow solid. 1 H NMR (200 MHz, CDCl 3 ) δ 7.61 (s, 1H), 7.37 (d, J=2.0 Hz, 1H), 7.31 (dd, J=2.2 Hz, 8.4 Hz, 1H), 7.25 (s, 1H), 7.18 (s, 1H), 6.96 (d, J=8.4 Hz, 1H), 3.96 (overlapping singlets, 12H). HRMS Calculated for C 19 H 19 BrNO 5 (M+H) − 420.0448. found 420.0465.
[0169] To 0.100 g (0.24 mmol) of 40 in 20 mL of DCM at −78° C. was added 2.5 mL of 1 M BBr 3 in DCM. The reaction was warmed to 23° C., stirred for 3 h, and quenched with 10 mL of MeOH. The reaction mixture was concentrated, and water was added to precipitate the product. This did not yield any solid, so the crude product was reconcentrated and purified by PTLC (10% MeOH in DCM) to give, after 2 weeks drying, 0.040 g (46% yield) of SA-84 as a yellow-green solid. 1 H NMR (200 MHz, DMSO-d 6 ) δ 7.50 (s, 1H), 7.44 (s, 1H), 7.16 (d, J=2.0 Hz), 7.09 (s, 1H), 7.08 (dd, coupling constants not resolvable due to overlapping singlet, 1H), 6.83 (d, J=8.2 Hz, 1H).
Example 26
Synthesis of SA-86
[0170]
[0171] To a mixture of 1-bromo-2-iodo-4,5-dimethoxybenzene (41) (27 mg, 0.078 mmol), Pd(PPh 3 ) 4 (4.1 mg, 5 mol %) and toluene (1 mL) was added the solution of 2-(3,4-dimethoxyphenyl)-5-(tributylstannyl)thiazole (SA-81) (36 mg, 0.070 mmol) and toluene (1 mL). The reaction was purged with nitrogen and refluxed 16 h. The concentrated reaction mixture was purified by PTLC (35% EtOAc in hexanes) and afforded 42 (20 mg, 65% yield).
[0172] SA-86 was prepared by the reaction of 5-(2-bromo-4,5-dimethoxyphenyl)-2-(3,4-dimethoxyphenyl) thiazole (42) (20 mg, 0.046 mmol) and BBr 3 (in DDM??) (0.46 mL, 0.46 mmol) according to the similar procedure for compound SA-58, and obtained SA-86 as a yellow solid quantitatively.
Example 27
Synthesis of SA-87
[0173]
[0174] 2-Bromo-4,5-dimethoxybenzoic acid (3) (4.50 g, 17.6 mmol), veratrole (2.44 g, 17.7 mmol), and 60 g of polyphosphoric acid (PPA) were heated to 80° C. for 45 min. The reaction mixture turned a deep orange color during this time. The crude mixture was treated with 400 mL of water, allowed stir overnight, and the resultant crude product was filtered as a brownish solid. The solid was recrystalized twice from ethanol to give 1.89 g (28% yield) of benzophenone 43. 1 H NMR (CDCl 3 , δ) 7.54 (d, J=2.0 Hz, 1H), 7.26 (dd, J=2.0, 8.0 Hz), 7.07 (s, 1H), 6.90-6.83 (overlapping peaks, 3H), 3.95 (s, 6H), 3.88 (s, 3H), 3.84 (s, 3H).
[0175] Benzophenone 43 (1.31 g, 3.4 mmol) in 10 mL DCM was added to a solution of 1.00 g NaBH 4 (26 mmol) in 10 mL of TFA. Caution: the reaction between NaBH 4 and TFA is extremely exothermic with the evolution of hydrogen gas. It is recommended that: (1) an ice bath be used when the addition is occurring and (2) NaBH 4 pellets are used as opposed to powder. The mixture was stirred 16 h, quenched with 15 mL of water, and diluted with 20 mL of DCM. The aqueous layer was made basic with 10 N NaOH, the layers were separated, the aqueous layer extracted with one portion of 10 mL DCM, and the organic layer dried with Na 2 SO 4 and concentrated. Flash 40+M column chromatography (Biotage) gave 1.15 g (91% yield) of 44 as a thick, yellow oil.
[0176] 1 H NMR (CDCl 3 , δ) 7.04 (s, 1H), 6.80 (d, J=8.2 Hz, 1H), 6.74-6.66 (overlapping peaks, 2H), 6.63 (s, 1H), 3.99 (s, 2H), 3.86 (s, 6H), 3.84 (s, 3H), 3.77 (s, 3H).
[0177] Bromide 44 (0.056 g, 0.172 mmol) in 2 mL of DCM was cooled to 0° C. and treated with 1 mL of 2 M BBr 3 in DCM. The mixture was stirred 2 h while allowing to warm to ˜23° C., quenched with methanol, and concentrated. The crude, concentrated product was treated with 10 mL of water, extracted twice with eight mL of ethyl acetate, and the organic layers were concentrated to give the SA-87 as an off-white solid.
[0178] 1 H NMR (CDCl 3 , δ) 6.93 (d, J=8.2 Hz, 1H), 6.62-6.57 (overlapping peaks, 2H), 6.51 (bs, 1H), 6.43-6.40 (m, 1H), 3.67 (s, 2H).
Example 28
Synthesis of SA-88 and SA-90
[0179]
[0180] 3,4-dimethoxybenzoic acid (1) (3.75 g, 20.6 mmol), veratrole (2.86 g, 20.7 mmol), and 80 g of polyphosphoric acid (PPA) were heated to 80° C. with stirring via overhead stirrer for 1 h. Water was added, and the mixture was stirred until a solid formed. This solid was filtered, recrystalized twice from ethanol, filtered, and dried to give 3.79 g (61% yield) of benzophenone 64.
[0181] 1 H NMR (CDCl, δ) 7.43 (d, J=2.0 Hz, 2H), 7.38 (dd, J=2.0, 8.2 Hz, 2H), 6.90 (d, J=8.2 Hz, 2H), 3.96 (s, 6H), 3.94 (s, 6H).
[0182] Benzophenone 64 (0.50 g, 1.66 mmol) was dissolved in 4 mL of DCM and added to a solution made from NaBH 4 (0.356 g, 9.4 mmol) and 3 mL TFA. The resultant mixture was stirred 18 h, diluted with 15 mL of DCM and 10 mL of water, made basic with 10 N NaOH, and the layers separated. The aqueous was extracted once more 10 mL of DCM, and the combined organic layers were dried and concentrated. The crude product was purified by PTLC to give 0.42 g (88% yield) of 65.
[0183] The previous reaction was repeated using 1.12 g of benzophenone 64 with the other reagents scaled appropriately, and gave 0.86 g (81% yield) of 65.
[0184] 1 H NMR (CDCl 3 , δ), 6.83-6.78 (m, 2H), 6.75-6.69 (m, 4H), 3.88-3.83 (multiple singlets, 14).
[0185] A solution of 65 (0.500 g, 1.7 mmol) in 3 mL of AcOH was treated with 0.120 g of 69% aq. HNO 3 (1.3 mmol) and stirred for 1.5 h. The mixture was poured into 50 mL of water, and extracted twice with 25 mL of ethyl acetate. The combined organic layers were washed three times with 20 mL of water, dried, and concentrated to give the crude product, which was purified by PTLC to give 0.123 g of 65 (25% recovery), 0.137 g (24% yield) of 67, and 0.041 g (6% yield) of 66.
[0186] 1 H NMR of 66 (CDCl 3 , δ), 7.65 (s, 2H), 6.54, (s, 2H), 4.66 (s, 2H), 3.93 (s, 6H), 3.80 (s, 6H). 1 H NMR of 67 (CDCl 3 , δ), 7.60 (s, 1H), 6.79-6.63 (overlapping peaks, 4H), 4.26 (s, 2H), 3.91-3.81 (m, 12H).
[0187] 13 C NMR of 67 (CDCl 3 , δ), 153.0, 149.1, 147.7, 147.3, 131.6, 131.3, 120.9, 113.6, 112.4, 111.3, 108.2, 56.42, 56.27, 55.9, 38.3.
[0188] A mixture of 66 (0.030 g, 0.08 mmol) in 3 mL of DCM was treated with 1 mL of 2 M BBr 3 and stirred 2.5 h. Methanol (10 mL) was added to quench the reaction, the mixture was concentrated, and water was added. The resultant brown solid was filtered and not purified further (due to lack of solubility of the product) to give 0.007 g (27% yield) of SA-88.
[0189] 1 H NMR (DMSO-d 6 , 8), 8.87 (bs, 2H), 8.71 (bs, 2H), 7.56 (s, 4H), 3.48 (s, 2H).
[0190] A mixture of 67 (0.030 g, 0.09 mmol) in 2 mL of DCM was treated with 1 mL of 2 M BBr 3 and stirred for 2.5 h. Methanol (10 mL) was added to quench the reaction, the mixture concentrated, and treated with 10 mL of water. This was extracted with 10 mL of ethyl acetate, dried, and concentrated to give 8 mg (32% yield) of SA-90 as a thick brown oil that slowly solidified.
[0191] 1 H NMR (DMSO-d 6 , δ), 7.54, (s, 3H), 6.97-6.93 (overlapping peaks, 2H), 6.50 (d, 1H, overlapping with next peak), 6.45 (d, J=2.0 Hz, 1H), 3.85 (s, 2H)
Example 29
Synthesis of SA-93
[0192]
[0193] 2-Iodo-4,5-dimethoxybenzoic acid (49) (2.76 g, 9.0 mmol), veratrole (1.20 g, 8.6 mmol), and 50 g of polyphosphoric acid (PPA) were heated to 90° C. for 15 mm. An additional 0.30 g (2.1 mmol) of veratrole was added. The reaction mixture turned a deep orange color during the reaction. The crude mixture was treated with 600 mL of ice water, sonicated, and the resultant crude product was filtered as a brownish solid (1.55 g, 40% yield). This product 50 was used without further purification.
[0194] Benzophenone 50 (1.55 g, 3.6 mmol) in 10 mL DCM was added to a solution of 2.00 g NaBH 4 (26 mmol) in 10 mL of TFA. Caution: the reaction between NaBH 4 and TFA is extremely exothermic with the evolution of hydrogen gas. It is recommended that: (1) an ice bath be used when the addition is occurring and (2) NaBH 4 pellets are used as opposed to powder. The mixture was stirred 16 h, quenched with 50 mL of water, and diluted with 15 mL of DCM. The aqueous layer was made basic with 10 N NaOH, the layers were separated, the aqueous layer extracted once with 25 mL DCM, and the organic layer dried with Na 2 SO 4 and concentrated. The crude product consisted of the iodo compound 51 and the des-iodo 46. The products practically co-elute when Flash 40+M column chromatography is used, so the crude was purified using PTLC with 0.4% ethyl acetate as the eluent and eluting the PTLC plates several times to give 0.30 g (20% yield) of 51 as a thick, yellow oil.
[0195] 1 H NMR (CDCl 3 , δ) 6.80 (d, J=8.0 Hz, 1H), 6.74-6.64 (overlapping peaks, 4H), 3.98 (s, 2H), 3.85 (bs, 9H), 3.75 (s, 3H).
[0196] 13 C NMR (CDCl 3 , δ) 149.5, 149.0, 148.1, 147.6, 136.3, 132.6, 121.8, 120.8, 113.1, 112.3, 111.3, 88.8, 56.2, 55.9, 45.6.
[0197] Iodide 51 (0.150 g, 0.36 mmol) in 40 mL of DCM was cooled to −78° C. and treated with BBr 3 (0.75 g, 3 mmol) neat. The mixture was stirred 2 h, allowed to warm to ˜23° C., stirred 3 h more, quenched with water, extracted with 20 mL ethyl acetate, and the organic dried and concentrated. The crude, concentrated product was precipitated with DCM, and filtered to give 0.022 g of SA-93 (17% yield).
[0198] 1 H NMR (DMSO-d 6 , δ) 6.62-6.52 (overlapping peaks, 3H), 6.50 (d, J=1.9 Hz, 1H), 6.41 (dd, J=2.0, 8.2 Hz, 1H), 3.54 (s, 2H), 4.5-3.5 (broad peak, 4H, “—OH”)
Example 30
Synthesis of SA-94 and SA-98
[0199]
[0200] A mixture of 3′,4′-dimethoxyacetophenone (52) (0.54 g, 3 mmol) and 3,4-dimethoxybenzaldehyde (0.51 g, 3.06 mmol) (30) in 15 mL of absolute ethanol was treated with 1.75 g of NaOH, sonicated for 10 min, then stirred overnight. The resultant mixture was cooled to 0° C., filtered, and washed with 4° C. ethanol to obtain a yellow solid that was dried to give 0.88 g of 53 (89% yield).
[0201] 1 H NMR (CDCl 3 , δ) 7.76 (d, J 15.4 Hz, 1H), 7.68 (dd, J 2.0, 8.4 Hz, 1H), 7.62 (d, J=2.0 Hz, 1H), 7.40 (d, J 15.4 Hz, 1H), 7.19 (dd, J=2.0, 8.4 Hz, 1H), 6.93 (d, J=8.0 Hz, 1H), 6.90 (d, J=8.0 Hz, 1H).
[0202] A solution of 53 (0.14 g, 0.43 mmol) was dissolved in 40 mL of DCM, cooled to −78° C., and BBr 3 (0.98 g, 3.9 mmol) in 4 mL of DCM was added. The mixture was allowed to warm to 0° C. over 2 h, and then immediately warmed to 23° C. The mixture was stirred 2 h, quenched with 20 mL of water, and extracted with 100 mL of ethyl acetate. The organic layer was dried, concentrated until˜5 mL remained, and treated with 30 mL of DCM. A deep purple solid precipitated from the solution. This solid was filtered, and dried to a yellow-green solid in the dark to give 0.068 g (59% yield) of SA-94.
[0203] 1 H NMR (DMSO-d 6 ) 10.5-8.0 (bs, 4H), 7.57-7.47 (m, 2H), 7.49 (s, 2H), 7.20 (bs, 1H), 7.12 (m, 1H), 6.84 (d, J=8.4 Hz, 1H), 6.79 (d, J=8.6 Hz, 1H).
[0204] A solution of 53 (0.082 g, 0.25 mmol) in 1.5 mL of acetic acid was treated with 0.5 mL of hydrazine hydrate and heated to 135° C. for 2 h and 140° C. for 1 h. The yellow color of the starting material gradually discharged throughout the course of the reaction. The crude reaction mixture was poured into 20 mL of water, extracted with 10 mL of ethyl acetate twice. The combined organic layers were washed twice with 20 mL of water, dried, and concentrated to give 0.058 g (61% yield) of 54 as a clear oil that was not purified further.
[0205] A solution of 54 (0.056 g, 0.59 mmol) in 20 mL of DCM was cooled to −78° C., and treated with BBr 3 (1.025 g, 4.1 mmol) in 5 mL of DCM. The mixture was stirred for 3 h at −78° C., stirred for 1 h at ˜0° C., and quenched with water. The resultant mixture was extracted with 100 mL of ethyl acetate, and the organic layer was dried and concentrated to give the crude product which was taken up in 2 mL of ethyl acetate, treated with 2 mL of hexanes, and treated with 50 mL of DCM. The precipitated product SA-98 (0.019 g, 40% yield) was collected by filtration and dried to give an off-white powder.
[0206] 1 H NMR (DMSO-d 6 ) 9.4 (bs, 1H), 9.2 (bs, 1H), 8.9 (bs, 1H), 8.8 (bs, 1H), 7.26 (d, J=2.2 Hz, 1H), 6.98 (dd, J=2.2, 8.4 Hz, 1H), 6.77 (d, J=8.2 Hz, 1H), 6.64 (d, J=8.4 Hz, 1H), 6.52 (d, J=2.2 Hz, 1H), 6.44 (dd, J=2.2, 8.0 Hz, 1H), 5.32 (dd, J=3.6, 11.0 Hz, 1H), 3.4 (m, 1H), 3.22 (m, 1H), 2.24 (s, 3H).
[0207] HRMS, Calculated for C 17 H 17 N 2 O 5 (M+H) + 329.1137. found 329.1125.
Example 31
Synthesis of SA-95
[0208]
[0209] A mixture of 3′,4′-dimethoxyacetophenone (52) (2 mmol, 0.36 g) and 6-bromoveratraldehyde (55) (2 mmol, 0.49 g) in 15 mL of ethanol was treated with 1 g of NaOH and 0.015 g (2.78 mmol) of NaOMe. The mixture was stirred at 23° C. for 18 h, cooled to 4° C., and the resultant yellow solid filtered to give the bromochalcone 56 as a yellow solid (0.68 g, 83% yield).
[0210] 1 H NMR (CDCl 3 , δ), 8.07 (d, J=15.6 Hz, 1H), 7.75 (m, 1H), 7.67 (d, J=1.8 Hz, 1H), 7.38 (m, 1H), 7.22 (s, 1H), 7.12 (s, 1H), 6.95 (d, J=8.2 Hz, 1H), 3.98-3.94 (overlapping singlets, 12H).
[0211] A mixture of bromochalcone 56 (0.20 g, 0.49 mmol) in 30 mL of DCM was cooled to −78° C. and treated with BBr 3 (0.72 g, 2.88 mmol) in 4 mL of DCM. The mixture was stirred at −78° C. for 2.5 h, warmed gradually to 0° C. over 1 h, warmed to 23° C., and stirred an additional 1 h. The reaction was quenched with 20 mL of water, and the mixture extracted with 50 mL of ethyl acetate. The ethyl acetate layer was washed once with 20 mL of brine, dried concentrated to 2 mL, and treated with 50 mL of DCM. The product was filtered and dried to get SA-95 as a reddish solid (0.056 g, 33% yield).
[0212] 1 H NMR (dmso-d 6 ) 10.2 (bs, 1H), 9.8 (bs, 1H), 9.3 (bs, 2H), 7.81 (d, J=15.4 Hz, 1H), 7.61 (d, J=2.2 Hz, 1H), 7.56-7.49 (overlapping peaks, 3H), 7.05 (s, 1H), 6.86 (d, J=8.2 Hz, 1H).
Example 32
Synthesis of SA-96
[0213]
[0214] A mixture of 2′-bromo-4′,5′-dimethoxyacetophenone (57) (0.390 g, 1.5 mmol) and 3,4 dimethoxybenzaldehyde (30) (0.310 g, 1.9 mmol) in 10 mL of ethanol was treated with 0.75 g of NaOH. The mixture was inverted ten times to thoroughly mix the starting materials, sonicated 5 mm, allowed to stand 2 h, and sonicated 5 min again. A yellow precipitate resulted, and this was filtered and dried to give bromochalcone 58 as a light yellow solid (0.482 g, 79% yield).
[0215] 1 H NMR (CDCl 3 , δ) 7.41 (d, J=2.2 Hz, 1H), 7.39-7.34 (m, 3H), 7.25 (s, 1H), 7.17 (d, J=16.0 Hz, 1H), 7.10 (s, 1H), 7.00 (d, J=8.4 Hz, 1H), 3.86-3.81 (overlapping singlets, 12H). 13 C NMR (CDCl 3 , δ) 194.0, 151.9, 151.1, 149.5, 148.5, 146.6, 133.4, 127.6, 124.6, 124.0, 116.5, 112.8, 112.1, 111.5, 110.2, 56.6, 56.4, 56.2, 56.1.
[0216] A mixture of bromochalcone 58 (0.27 g, 0.66 mmol) in 30 mL of DCM was cooled to −78° C., and treated with 1.25 g (5 mmol) of BBr 3 in 5 mL of DCM. The mixture was stirred at −78° C. for 3 h, warmed immediately to 23° C., stirred at 23° C. for 1 h, quenched with 20 mL of water, and extracted with 125 mL of ethyl acetate. The organic layer was dried and concentrated to 1 mL. The concentrate was treated with an excess of DCM to precipitate a purplish-red solid that was filtered and dried to give SA-96 as a reddish-brown solid (0.036 g, 16% yield).
[0217] 1 H NMR (DMSO-d 6 , δ) 7.26 (d, J=16.0 Hz, 1H), 7.09 (bs, 1H), 7.05-6.86 (overlapping peaks, 4H), 6.77 (d, J=8.2 Hz, 1H).
Example 33
Synthesis of SA-97
[0218]
[0219] A mixture of 2,4,5-trimethoxybenzoic acid (59) (1.06 g, 5 mmol), veratrole (0.69 g, 5 mmol), and 10 g of PPA was heated with a heat gun and stirred with a stirring rod for 20 min. Water (100 mL) was added to the reaction mixture and the resultant mixture was cooled to 4° C. and stirred with a stirring rod for 20 min. The water was decanted and the resultant grey, gummy solid was taken up in a hot solution 20 mL of reagent alcohol and 10 mL of water. The mixture was cooled and filtered to give 0.43 g of orange crystals. Water (40 mL) was added to the filtrate and the resultant orange solid was filtered to give 0.72 g of amorphous orange solid. Both fractions were the desired 60 (1.15 g, 69% yield).
[0220] A mixture of benzophenone 60 (0.93 g, 2.9 mmol) in 20 mL of DCM was added to 0.92 g of NaBH 4 (24.3 mmol) in 10 mL of TFA. Caution: the reaction between NaBH 4 and TFA is extremely exothermic with the evolution of hydrogen gas. It is recommended that: (1) an ice bath be used when the addition is occurring and (2) NaBH 4 pellets are used as opposed to powder. The mixture was stirred for 6 h, and an additional portion of NaBH 4 (0.53 g, 14.0 mmol) was added. The mixture was stirred 20 h, diluted with 50 mL of DCM and 50 mL of water, and the aqueous layer made basic with NaOH. The layers were separated, and the aqueous layer was extracted once with 50 mL of DCM. The organic layers were combined, dried, and concentrated to give a yellow oil that was purified by Flash 40+M chromatography (Biotage) to give 61 as a pale yellow, thick oil (0.63 g, 71% yield).
[0221] 1 H NMR (CDCl 3 , δ) 6.83-6.76 (overlapping peaks, 3H), 6.66 (s, 1H), 6.57 (s, 1H), 3.91-3.86 (overlapping singlets, 11H), 3.83 (s, 3H), 3.79 (s, 3H).
[0222] A mixture of pentamethoxy compound 61 (0.262 g, 0.82 mmol) in 30 mL of DCM at −78° C. was treated with BBr 3 (2.00 g, 8 mmol) in 8 mL of DCM. The resultant mixture was stirred at −78° C. 1 h, warmed to 23° C. immediately, stirred at 23° C. for 4 h, quenched with 20 mL of water and extracted with 100 mL of ethyl acetate. The ethyl acetate layer was concentrated to dryness, taken up in approximately 0.5 mL of ethyl acetate, precipitated with DCM, cooled to −20° C., and filtered to give SA-97 as a white solid (0.93 g, 46% yield).
[0223] 1 H NMR (DMSO-d 6 ) 8.63-8.29 (bs, 4H), 6.58 (d, J=7.8 Hz, 1H), 6.52 (d, J=2.0 Hz, 1H), 6.40 (dd, J=2.0, 8.0 Hz, 1H), 6.29 (s, 1H), 6.26 (s, 1H), 3.50 (s, 2H).
Example 34
Synthesis of SA-99
[0224]
[0225] A mixture of dibromide 62 (0.562 g, 2 mmol), boronic acid 15 (0.910 g, 5 mmol), 20 mL of dioxane, and 24 mL of 2 M Na 2 CO 3 (aqueous) was degassed by nitrogen purge. Then Pd(PPh 3 ) 4 (0.12 g, 0.10 mmol) was added. The resultant mixture was refluxed 20 h, diluted with 50 mL of water, and extracted three times with 50 mL of ethyl acetate. The combined organic layers were washed once with 50 mL of water, dried, and concentrated to give the crude product. This was purified by Flash 40+M chromatography (Biotage) using gradient ethyl acetate in hexanes as the eluent to give 63 as a yellow solid (0.288 g, 36% yield).
[0226] 1 H NMR (CDCl 3 , δ), 7.94 (d, J=1.8 Hz, 1H), 7.75 (dd, J=1.8, 8.0 Hz, 1H), 7.47 (d, i=8.0 Hz, 1H), 7.17 (dd, J=2.2, 8.2 Hz, 1H), 7.10 (d, J=2.0 Hz, 1H), 6.96 (d, J=8.0 Hz, 1H), 6.90-6.85 (overlapping peaks, 3H), 3.95 (s, 3H), 3.92 (s, 3H), 3.90 (s, 3H), 3.87 (s, 3H).
[0227] 13 C NMR (CDCl 3 , δ) 149.9, 149.7, 149.6, 149.3, 149.1, 141.1, 133.9, 132.2, 131.2, 130.0, 129.5, 121.8, 120.5, 119.6, 111.7, 111.4, 111.2, 110.1, 56.11, 56.05, 56.0, 55.9.
[0228] A solution of 63 (0.062 g, 0.16 mmol) in 25 mL DCM was cooled to −78° C., treated with BBr 3 (1.125 g, 4.5 mmol) in 6 mL of DCM, stirred 2.5 h at −78° C., warmed to 23° C., stirred at −23° C. for 1.5 h, quenched with 20 mL water, and extracted once with 100 mL of ethyl acetate. The ethyl acetate layer was dried and concentrated to 3 mL and precipitated with excess DCM. The precipitate was filtered and dried to give SA-99 as a yellow solid (0.037 g, 70% yield).
[0229] 1 H NMR (DMSO-d 6 ) 9.17-9.11 (bs, 411), 7.96 (d, J=1.6 Hz, 1H), 7.83 (dd, J=2.2, 8.2 Hz, 1H), 7.49 (d, J=8.0 Hz, 1H), 7.14 (bs, 1H), 7.08 (d, J=8.4 Hz, 1H), 6.88-6.79 (overlapping peaks, 2H), 6.72 (d, J=2.2 Hz, 1H), 6.63 (dd, J=2.0, 8.2 Hz, 1H), HRMS Calculated for C 18 H 13 NO 6 Na (M+Na) + 362.0641. Found 362.0645.
Example 35
Synthesis of SA-108
[0230]
[0231] To 1.00 g (4.07 mmol) of acid chloride 68 in 25 mL of DCM at 0° C. was added 5 mL of pyridine. The mixture was stirred 3 min, and 0.76 g (3.87 mmol) of known hydrazide 69 was added at once. The mixture was gradually allowed to warm to 21-23° C. and stirred at this temperature for 16 h. The mixture was concentrated, treated with 10 mL of ethanol, warmed to reflux, and diluted with 30 mL of water. After returning the mixture to reflux, ethanol was added gradually until a solution formed. The solution was allowed to cool, and the precipitated light yellow solid was collected and dried to give 0.498 g (1.24 mmol, 32% yield) of 70.
[0232] 1 H NMR (CDCl 3 and MeOD, δ) 7.54 (s, 1H), 7.45 (dd, J=2.2, 8.4 Hz, 1H), 7.39 (d, J=1.8 Hz), 7.16 (s, 1H), 6.82 (d, J=8.4 Hz, 1H), 3.98-3.73 (overlapping singlets+residual H 2 O peak, 1211).
[0233] A mixture of 0.398 g (1 mmol) of 70 and 0.452 g (1.11 mmol) of Lawesson's reagent in 50 mL of THF were refluxed for 16 h. The mixture was concentrated and purified by PTLC using 10% EtOAc in DCM as the elutent to give 0.255 g (0.62 mmol, 62% yield) 71 as a bright yellow solid.
[0234] 1 H NMR (DMSO-d 6 ) 7.77 (s, 1H), 7.60-7.58 (overlapping peaks, 2H), 7.40 (s, 1H), 7.15 (d, J=8.8 Hz, 1H), 3.97 (s, 3H), 3.95 (s, 3H), 3.89 (s, 3H), 3.87 (s, 3H).
[0235] A mixture of 0.100 g (0.24 mmol) of 71 in 5 g of pyridine hydrochloride was heated to 200° C. for 30 min. The mixture was cooled, treated with 30 mL of water, and filtered. The resultant solid was recrystalized from aqueous methanol to yield 0.016 g of a brown solid as SA-108. The product is only sparingly soluble in DMSO-d 6 , and insoluable in other deuterated solvents or solvent mixtures.
[0236] 1 H NMR (DMSO-d 6 , δ), 8.79 (s, 1H), 7.80 (bs, 1H), 7.57 (s, 1H), 7.43 (m, 1H), 7.28 (m, 1H), 6.91 (s, 1H), 6.80 (d, J=8.0 Hz, 1H). Example 1—Compounds provided herein bind are potent disruptors/inhibitors of Parkinson's disease α-synuclein fibrils
Example 36
Compounds Provided Herein are Potent Disruptors/Inhibitors of Parkinson's Disease α-Synuclein Fibrils
[0237] The compounds were found to be potent disrupters/disaggregators of α-synuclein fibrils. In this set of studies, the efficacy of certain compounds provided herein to cause a disassembly/disruption/disaggregation of pre-formed fibrils of Parkinson's disease (i.e. consisting of α-synuclein fibrils) was analyzed. For the studies described below in Parts A and B, 69 μM of α-synuclein (rPeptide, Bogart, Calif.) was first incubated at 37° C. for 4 days in 20 mM sodium acetate buffer at pH 4 with circular shaking (1,300 rpm) to cause α-synuclein aggregation and fibril formation.
Part A: Thioflavin T Fluorometry Data
[0238] In one study, Thioflavin T fluorometry was used to determine the effects of the compounds on α-synuclein fibrils. In addition to test compounds, this experiment included a positive control compound and a negative control compound for reference. In this assay Thioflavin T binds specifically to fibrillar amyloid, and this binding produces a fluorescence enhancement at 485 nm that is directly proportional to the amount of fibrils formed. The higher the fluorescence, the greater the amount of fibrils formed (Naki et al., Lab. Invest. 65:104-110, 1991; Levine III, Protein Sci. 2:404-410, 1993; Amyloid: Int. J. Exp. Clin. Invest. 2:1-6, 1995).
[0239] Following initial α-synuclein fibrilization as described above, 6.9 μM α-synuclein was incubated at 37° C. for 2 days with shaking (1,300 rpm), either alone, or in the presence of one of the compounds (at test compound:α-synuclein molar ratios of 50:1, 10:1, 5:1, 1:1, 0.5:1, 0.1:1, 0.05:1 and 0.01:1) in phosphate-buffered saline, pH 7.4+0.02% sodium azide. Following 2 days of co-incubation, 50 μl of each incubation mixture was transferred into a 96-well microtiter plate containing 150 μl of distilled water and 50 μl of a Thioflavin T solution (i.e. 500 μM Thioflavin T in 250 μM phosphate buffer, pH 6.8). The final concentration of Thioflavin T reagent is 100 μM in 50 μM phosphate buffer, pH 6.8. The fluorescence was read at 485 nm (444 nm excitation wavelength) using an ELISA plate fluorometer after subtraction with buffer alone or compound alone, as blank.
[0240] The results of the 2-day incubations are presented below. For each compound, the % inhibition of Thioflavin T fluorescence (i.e. the decrease compared to control reactions containing α-synuclein alone) was plotted against the log of the concentration of the test compound (expressed as mole ratio relative to α-synuclein). Where possible, the effective concentration of SA compound that yields 50% of maximal % decrease of Thioflavin T fluorescence (EC 50 ) was calculated from the sigmoidal shaped dose response curve. The compounds (SA-52, SA-53, SA-54, SA-55, SA-57, SA-58, SA-59, SA-61, SA-62, SA-63, SA-64, SA-66, SA-67, SA-68, SA-69, SA-70, SA-72, SA-73, SA-93, SA-94, SA-95, SA-96, SA-97, SA-98 and SA-99 and positive reference compound #1) all caused a dose-dependent and extensive disruption/disassembly of preformed α-synuclein fibrils (Table 1). For example, compound SA-57 caused a significant (p<0.01 relative to α-synuclein alone) nearly complete inhibition (97-100%) when used at test compound:α-synuclein molar ratios >5:1 and a significant 83% inhibition when used at a test compound:α-synuclein molar ratio of 1:1 ( FIG. 1 ), whereas the negative reference compound showed no significant inhibition of Thioflavin T fluorescence at any of the concentrations tested (not shown). The EC 50 of SA-57 for inhibition of Thioflavin T fluorescence was determined to be 0.23 moles of test compound per mole of α-synuclein (Table 1). For the compounds described here that caused a dose-dependent disruption/disassembly of α-synuclein fibrils, the maximum % inhibition ranged from 76-100% and the EC 50 values ranged from 0.08-4.3 moles of test compound:α-synuclein, with most compounds showing highly potent effects (i.e. EC 50 <1 mole of test compound:α-synuclein) in this assay.
[0241] This study indicated that the compounds provided herein are potent disrupters/dissaggregators of Parkinson's disease α-synuclein fibrils, and usually exert their effects in a dose-dependent manner.
[0000]
TABLE 1
SA compounds disrupt/disaggregate α-synuclein
aggregates as measured by Thioflavin T fluorometry.
SA #
EC 50 (mole ratio)
Max % Decrease
52
0.28
99
53
0.17
100
54
0.74
98
55
0.08
92
57
0.23
100
58
0.19
100
59
0.58
96
61
0.10
100
62
1.09
95
63
0.86
100
64
0.39
100
66
0.69
100
67
4.3
76
68
0.77
100
69
0.73
88
70
0.17
100
72
0.12
100
73
0.52
100
93
0.16
100
94
0.15
100
95
0.16
100
96
0.14
100
97
0.16
99
98
0.65
100
99
0.65
100
Positive Reference #1
0.24
100
Negative Reference
not determined
0
Part B: Congo Red Binding Data
[0242] In the Congo red binding assay, the ability of a given test compound to alter α-synuclein aggregate binding to Congo red is quantified. In this assay Congo red binds specifically to fibrillar amyloid, and this binding is directly proportional to the amount of fibrils formed. Following initial α-synuclein fibrilization as described above, α-synuclein aggregates and test compounds were incubated for 2 days and then vacuum filtered through a 0.2 μm filter. The amount of α-synuclein retained in the filter was then quantitated following staining of the filter with Congo red. After appropriate washing of the filter, any lowering of the Congo red color on the filter in the presence of the test compound (compared to the Congo red staining of the amyloid protein in the absence of the test compound—i.e. α-synuclein alone) was indicative of the test compound's ability to diminish/alter the amount of aggregated and congophilic α-synuclein and thus cause disassembly/disruption/disaggregation of α-synuclein fibrils.
[0243] In one study, the ability of α-synuclein fibrils to bind Congo red in the absence or presence of increasing amounts of the compounds provided herein, including a positive and a negative reference compound (at test compound:α-synuclein molar ratios of 50:1, 10:1, 5:1, 1:1, 0.5:1, 0.1:1, 0.05:1, 0.01:1) was determined. The results of 2-day incubations are presented in Table 2 below. Whereas the negative reference compound caused no significant inhibition of α-synuclein fibril binding to Congo red at all concentrations tested (not shown), the test compounds caused a dose-dependent inhibition of α-synuclein binding to Congo red. For example, compound SA-57 caused a significant (p<0.01) inhibition (66%) when used at a test compound:α-synuclein molar ratio of 50:1 and a significant 49% inhibition when used at a test compound:α-synuclein molar ratio of 5:1 ( FIG. 2 ). The EC 50 of SA-57 for inhibition of Congo Red binding was determined to be 2.0 moles of test compound per mole of α-synuclein (Table 2). For the compounds described here that caused a dose-dependent disruption/disassembly of α-synuclein fibrils, the maximum % inhibition ranged from 25-94% and the EC 50 values ranged from 1.0-15.9 moles of test compound per mole of α-synuclein. Taken together, the results of this study indicated that compounds of this invention disrupt/disaggregate/disassemble α-synuclein aggregates as indicated by their ability to inhibit Parkinson's disease type α-synuclein fibril binding to Congo red, and usually exert their effects in a dose-dependent manner.
[0000]
TABLE 2
SA compounds disrupt/disaggregate α-synuclein fibrils/aggregates
as measured by Congo Red binding assay.
SA #
EC 50 (mole ratio)
Max % Decrease
52
10.7
68
53
6.8
75
54
15.9
57
55
4.5
38
57
2.0
66
58
1.9
94
59
7.6
85
61
2
84
63
9.5
72
64
2.3
85
66
2.2
48
67
6.8
25
68
6.4
60
69
14.2
39
70
3.4
88
72
2.9
29
73
1.1
35
93
1.9
62
94
4.5
65
95
4.5
64
96
5.1
72
97
1.0
40
98
10.1
44
99
14.2
54
Positive Reference #1
4.5
66
Negative Reference
not determined
0
Example 37
Compounds of this Invention are Potent Disruptors/Inhibitors of α-Synuclein Fibrils and/or Aggregates Associated with Parkinson's Disease
[0244] Parkinson's Disease is characterized by the accumulation of insoluble intraneuronal aggregates called Lewy Bodies, a major component of which is α-synuclein (reviewed in Dauer et al., Neuron, 39:889-909, 2003). Since autosomal dominant mutations in α-synuclein cause a subset of familial Parkinson's disease, and since these mutations increase the likelihood of α-synuclein to aggregate and form Lewy Bodies, aggregated α-synuclein is proposed to be directly involved in the etiology and disease progression (Polymeropoulos et al., Science 276:1197-1199, 1997; Papadimitriou et al., Neurology 52:651-654, 1999). Structural studies have revealed that intracellular Lewy bodies contain a large proportion of misfolded proteins with a high degree of β-pleated sheet secondary structure. Therefore, since many of the compounds described herein cause disassembly/disruption/disaggregation of α-synuclein aggregates in the in vitro assays (Thioflavin T fluorometry and Congo Red binding assays) described above, studies were also conducted in living cells to determine the efficacy of these compounds to inhibit or prevent α-synuclein aggregation associated with Parkinson's disease.
[0245] To test the therapeutic potential of the compounds, two cell-based assays were utilized. In both assays, rotenone is used to induce mitochondrial oxidative stress and cause α-synuclein aggregation. The first assay utilizes the binding of the fluorescent dye Thioflavin S to structures with high 0 sheet content, including α-synuclein fibrils. Therefore, quantitative assessment of the extent of Thioflavin S-positive staining of fixed cells is used to test the ability of the test compounds to inhibit/prevent or decrease the amount of α-synuclein aggregates relative to cells that were treated with rotenone only. In the second assay, cell viability is assessed using the XTT cytotoxicity assay (Cell Proliferation Assay Kit II, Roche, Mannheim, Germany), which is dependent on intact, functional mitochondria in live cells. Thus, the XTT cytotoxicity assay is used to test the ability of the compounds to ameliorate the mitochondrial toxicity and resulting loss of viability associated with the accumulation of α-synuclein aggregates. These studies are presented in the following examples.
[0246] To carry out these studies, a cell culture model was used in which human α-synuclein aggregation is experimentally induced. BE-M17 human neuroblastoma cells stably transfected with A53T-mutant human α-synuclein were obtained. Cell culture reagents were obtained from Gibco/Invitrogen, and cells were grown in OPTIMEM supplemented with 10% FBS, Penicillin (100 units/ml), Streptomycin (100 μg/ml) and 500 μg/ml G418 as previously described (Ostrerova-Golts et al., J. Neurosci., 20:6048-6054, 2000).
[0247] Thioflavin S is commonly used to detect aggregated protein structures in situ, including in brain tissue (Vallet et al., Acta Neuropathol., 83:170-178, 1992), and cultured cells (Ostrerova-Golts et al., J. Neurosci., 20:6048-6054, 2000), whereas Thioflavin T is often used as an in vitro reagent to analyze the aggregation of soluble proteins into fibrils enriched in β-pleated sheet structures (LeVine III, Prot. Sci., 2:404-410, 1993). Therefore, Thioflavin S histochemistry was used on cultured cells to detect aggregates containing a high degree of β-pleated structures that formed in response to oxidative stress-inducing agents (in this case rotenone) as previously described, with minor modifications (Ostrerova-Golts et al., J. Neurosci., 20:6048-6054, 2000). Briefly, for these studies cells were grown on Poly-D-Lysine coated glass slide chambers at approximately 4.5-5.5×10 4 cells/cm 2 . After 16-18 hours, cells were treated with 500 nM or 2 μM rotenone (Sigma) or vehicle (0.05% DMSO) as indicated. Within 15 minutes of rotenone (or vehicle) addition, compounds were added at the indicated concentration, or mock-treatment was performed in which cell culture media only (no compound) was added. Identical treatments were repeated after 48 hours. After an additional 24 hours, cells were fixed for 25 minutes in 3% paraformaldehyde. After a PBS wash and a deionized water wash, the cells were incubated with 0.015% Thioflavin S in 50% ethanol for 25 minutes, washed twice for four minutes in 50% ethanol and twice for five minutes in deionized water and then mounted using an aqueous-based mountant designed to protect against photobleaching. Aggregates that bind to Thioflavin S were detected with a fluorescent microscope using a High Q FITC filter set (480 to 535 nm bandwidth) and a 20× objective lens unless otherwise indicated. Between 8 and 20 (usually 16-18) representative images per condition were selected and imaged using Q Capture software by an experimenter who was blinded to treatment conditions. To assess the amount of Thioflavin 5-positive aggregates, the total area per field covered by Thioflavin S-positive inclusions was determined by image analysis and quantitation. For this purpose, background fluorescence that failed to exceed pre-set size or pixel intensity threshold parameters was eliminated using Image Pro Plus software. Spurious, non-cell associated fluorescence was manually removed. Unless indicated otherwise, comparisons between groups were made by comparing mean relative amounts of Thioflavin S-positive inclusions for a given treatment condition (i.e. cells treated with rotenone only versus cells treated with rotenone and test compound at a given concentration). Statistical analyses were performed with GraphPad Prism (GraphPad Inc). Differences between means (two samples) were assessed by the Student's t test. Differences among multiple means were assessed by one-factor ANOVA followed by Dunnett's post hoc test, compared to rotenone only treated cells. The data presented in Table 3 represent statistically significant (p<0.05) reductions (reported as percent inhibition) in Thioflavin S fluorescence in cells treated with test compound and rotenone relative to cells treated with rotenone only.
[0248] To validate the ability of the assay to quantitatively detect aggregates that bind Thioflavin S, staining of BE-M17 cells overexpressing A53T α-synuclein was carried out and the results revealed a rotenone dose-dependent increase in Thioflavin S-positive aggregates relative to vehicle-treated control cells ( FIG. 3 ). Higher magnification images obtained with a 40× objective indicated that the Thioflavin S-positive aggregates were intracellular and cytoplasmic, analogous to the accumulation of intracytoplasmic Lewy bodies that are pathological hallmarks associated with Parkinson's disease (not shown). Quantitation of the area covered by Thioflavin-S-positive aggregates established that 500 nM and 2 μM rotenone were sufficient to induce robust aggregation ( FIG. 3 ) and thus are effective doses to test the ability of compounds to attenuate the formation of these aggregates.
[0249] Using the protocol described above, several selected compounds were tested for their ability to reduce, inhibit, prevent or eliminate Thioflavin S-positive aggregates in rotenone-treated BE-M17 cells overexpressing A53T α-synuclein. Examples of results obtained from experiments using these compounds are summarized in Table 4. Many of the compounds tested significantly disrupted, prevented or inhibited α-synuclein aggregation and fibril formation in the presence of rotenone as indicated by a decrease in Thioflavin S-positive inclusions, relative to cells treated with rotenone only. For example, cells treated with 500 nM rotenone only exhibited a robust presence of Thioflavin S-positive aggregates (not shown), whereas addition of 500 nM, 1 μM or 5 μM SA-72 markedly reduced the abundance of these rotenone-induced aggregates by 63%, 65% and 83%, respectively, relative to rotenone only-treated cells (Table 3). Similarly, in cells treated with 2 μM rotenone only, there was a robust presence of Thioflavin S-positive aggregates (not shown), whereas addition of 500 nM or 1 μM SA-72 markedly reduced the abundance of these rotenone-induced aggregates by 67% and 42%, respectively, relative to rotenone only-treated cells (Table 3). Therefore, SA-72 reduced, inhibited, prevented and/or eliminated Thioflavin S-positive aggregates in cells that express human A53T α-synuclein.
[0250] In addition to SA-72, compounds SA-52, SA-53, SA-54, SA-58, SA-59, SA-61, SA-62, SA-66, SA-67, SA-68, SA-93, SA-94, SA-95, SA-96 and SA-98, at given concentrations, all showed significant disruption/prevention/inhibition of rotenone-induced Thioflavin S-positive inclusions when tested in a similar fashion. These results are summarized in Table 3.
[0251] Taken together, we concluded that the tested compounds SA-52, SA-53, SA-54, SA-58, SA-59, SA-61, SA-62, SA-66, SA-67, SA-68, SA-72 SA-93, SA-94, SA-95, SA-96 and SA-98 effectively and potently reduced, prevented and/or inhibited the formation, deposition and/or accumulation of α-synuclein aggregates in A53T α-synuclein-expressing BE-M17 cells.
[0000]
TABLE 3
SA compounds prevent/inhibit rotenone-induced Thioflavin
S-positive α-synuclein aggregates in cells.
Concentration in μM
Efficacy
SA #
rotenone
compound
% Inhibition
52
2
5
49
53
2
2
71
54
0.5
0.5
80
0.5
2
83
2
1
56
58
0.5
2
68
2
2
63
59
0.5
1
69
0.5
2
76
0.5
5
56
2
1
67
61
0.5
0.5
36
0.5
5
48
62
0.5
0.5
81
0.5
1
55
0.5
5
85
66
0.5
0.5
39
0.5
1
32
0.5
5
94
2
0.5
57
2
1
69
67
0.5
0.5
75
0.5
1
48
0.5
2
92
68
0.5
1
69
0.5
5
73
2
5
44
72
0.5
0.5
63
0.5
1
65
0.5
5
83
2
0.5
67
2
1
42
93
2
2
45
94
0.5
2
85
2
0.5
70
2
1
63
95
0.5
0.5
73
0.5
1
98
0.5
2
90
2
0.5
95
96
0.5
1
82
2
0.5
73
2
2
81
98
0.5
0.5
74
2
1
76
Positive Ref. #1
0.5
0.5
47
0.5
1
65
0.5
2
70
2
0.5
49
2
1
56
2
2
60
Negative Ref.
0.5
5
none detected
2
5
none detected
Example 38
Compounds of this Invention are Neuroprotective Against Rotenone-Induced Cytotoxicity
[0252] The XTT cytotoxicity assay (Cell Proliferation Assay Kit II) was previously used to demonstrate that A53T α-synuclein potentiates cell death in BE-M17 cells through an oxidative stress-dependent mechanism (Ostrerova-Golts et al., J. Neurosci., 20:6048-6054, 2000). Research has shown that the accumulation of α-synuclein fibrils in Lewy bodies contributes mechanistically to the degradation of neurons in Parkinson's disease and related disorders (Polymeropoulos et al., Science 276:2045-2047, 1997; Kruger et al., Nature Genet. 18:106-108, 1998). Here, the XTT Cell Proliferation Assay Kit II (hereafter referred to as the XTT assay) was used to measure the ability of compounds to provide neuroprotection against rotenone-induced cytotoxicity. The assay is based on the principle that conversion of the yellow tetrazolium salt XTT to form an orange formazan dye (that absorbs light around 490 nm) occurs only in metabolically active, viable cells. Therefore, light absorbance at 490 nm is proportional to cell viability. For this assay, cells were plated in 96 well tissue culture dishes at 10 4 cells per well. After 16-18 hours, cells were treated with 500 nM rotenone, or vehicle (0.05% DMSO) as indicated. Approximately 15 minutes after rotenone addition, compounds were added at the indicated concentration. As a control, compounds were added without rotenone (in the presence of 0.05% DMSO vehicle) and resulted in no toxicity at the doses presented. Mock-treatment consisted of cell culture media only (no compound), in the presence or absence of rotenone. After 44-46 hours of treatment, conditioned media was removed and replaced with 100 μl fresh media and 50 μl XTT labeling reaction mixture according to the manufacturer's recommendations. Five to six hours later, the absorbance at 493 nm was measured and corrected for absorbance at the 620 nm reference wavelength. Treatment with 500 nM rotenone decreased viability by 30-40%. Percent inhibition of cell death was calculated as the proportion of the rotenone-induced absorbance (viability) decrease that was eliminated by SA compound treatment.
[0253] Using the protocol described above, several selected compounds were tested for their ability to provide neuroprotection against the rotenone-induced loss of cell viability (cell death) in A53T α-synuclein-expressing BE-M17 cells. In this series of experiments, there was a 30-40% loss of viability (cell death) in 500 nM rotenone-treated cells, relative to vehicle-treated cells, as expected. However, treatment with the compounds SA-52, SA-58, SA-59, SA-60, SA-61, SA-62, SA-64, SA-67, SA-68, SA-69, SA-70, SA-72, SA-73, SA-93, SA-94, SA-95, SA-96, SA-97, SA-98, and both positive reference compounds 2 and 3, resulted in a significant, dose-dependent inhibition of rotenone-induced cell death. To define the relative potency of each compound, the % inhibition of cell death was plotted against the log of the dose (μM), and, when possible, the 50% inhibitory concentration (IC 50 ) was calculated from the dose response curve. For example, treatment with 3.5 μM SA-94 resulted in 35% inhibition of cell death and treatment with 15 SA-94 resulted in 58% inhibition of cell death, with a calculated IC 50 of 2.3 μM ( FIG. 4 ), whereas treatment with the negative reference compound showed no inhibition of rotenone-induced cell death in this dose range (not shown). The positive results from this assay for the compounds described herein are summarized in Table 4.
[0254] Taken together, we concluded that the tested compounds that were efficacious in inhibiting rotenone-induced cytotoxicity demonstrate neuroprotective activity against α-synuclein toxicity in this system.
[0000]
TABLE 4
SA compounds prevent/inhibit rotenone-induced cell
death in A53T-mutant α-synuclein neuroblastoma cells
SA #
IC 50 (μM)
Max % Inhibition
52
23.8
64
58
3.5
100
59
3.1
63
60
12.5
33
61
3.6
93
62
3.6
31
64
2.6
100
67
8.5
44
68
24
61
69
35-75
30
70
5.6
78
72
10.3
39
73
35-75
77
93
19.8
100
94
2.3
58
95
3.8
63
96
4.3
61
97
39
42
98
48
56
Positive Ref. #2
4.2
72
Positive Ref. #3
10.6
82
Negative Ref.
not determined
0
Example 39
Compounds of this Invention Directly Inhibit the In Vitro Conversion of α-Synuclein to β-Sheet Containing Structures
[0255] As described above, Thioflavin S histochemistry in α-synuclein expressing cells was used to detect aggregates containing a high degree of β-pleated sheet structures that formed in response to rotenone treatment. Since several compounds were shown to reduce the abundance of Thioflavin S-positive aggregates (Example 3), we sought independent confirmation that the compounds directly inhibit the conversion of α-synuclein to β-sheet containing structures by using circular dichroism (CD) spectroscopy. For this purpose, α-synuclein was obtained from rPeptide as a lyophilized salt in 1 mg aliquots. Buffer components and other solvents were obtained from Sigma as A.C.S. Reagent grade or higher. Wild-type α-synuclein was dissolved in a buffer containing 9.5 mM phosphate, 137 mM sodium chloride and 2.7 mM potassium chloride (phosphate-buffered saline; PBS), and the pH was adjusted to pH 7.4. This solution was then re-lyophilized and dissolved in 0.5 mL deionized water at 2 mg/mL (138 μM), and an aliquot taken and diluted to 0.05 mg/mL in PBS for CD spectral analysis (t=0, unfolded reference control). In order to induce aggregation, 1 mg/ml α-synuclein (69 μM) was incubated at 37° C. for 24 hours with shaking (1,300 rpm), either alone, or in the presence of one of the test compounds (at test compound:α-synuclein molar ratios of 5:1, 1:1, 0.5:1, 0.1:1, 0.05:1, 0.01:1). After 24 hours, reactions were diluted 20-fold in PBS and CD spectra for each reaction were acquired on a Jasco J-810 spectropolarimeter using a 0.1 cm path length cell. All spectra were recorded with a step size of 0.1 nm, a bandwidth of 1 nm, and an α-synuclein concentration of 0.05 mg/ml. The spectra were trimmed at the shortest wavelength that still provided a dynode voltage less than 600V. The trimmed spectra were then subjected to a data processing routine beginning with noise reduction by Fourier transform followed by subtraction of a blank spectrum (vehicle only without α-synuclein). These blank corrected spectra were then zeroed at 260 nm and the units converted from millidegrees to specific ellipticity.
[0256] Percent β-sheet was determined from processed spectra using the ellipticity minimum value at approximately 218 nm and referencing to a scale normalized to nearly fully folded and unfolded reference values, consistent with previous reports (Ramirez-Alvarado et al., J. Mol. Biol., 273:898-912, 1997; Andersen et al., J. Am, Chem. Soc., 121:9879-9880, 1999) The fully folded reference value was found by performing the described calculation on the spectrum of α-synuclein fibrillized for 24 hours (complete fibrilization), and assigning this difference the arbitrary value of 100% β-sheet. The unfolded reference was provided by the spectrum from the same sample at the initial time point (t=0) and ascribing the difference found here the arbitrary value of 0% β-sheet. These percent β-sheet values were then used to provide the respective relative % inhibition of β-sheet induced by the compounds at given molar ratio of test compound:α-synuclein. For each compound, the % inhibition of β-sheet formation was plotted against the log of the concentration (mole ratio) of the test compound and, where possible, the 50% inhibitory concentration (IC 50 ) was calculated from the dose response curve.
[0257] First, in order to confirm that α-synuclein is indeed converted to a β-sheet-rich structure and to establish the timing of this conversion at 24 hours in our system, an aliquot of the α-synuclein only incubation mixture (without compounds) was sampled at various time points and CD spectra collected. At 24 hours of incubation, CD analysis revealed a large abundance of a β-sheet-rich structure, indicated by the pronounced specific ellipticity minimum at 218 nm and maximum at 197 nm (not shown). However, when test compounds SA-54, SA-55, SA-57, SA-58, SA-59, SA-61, SA-62, SA-64, SA-67, SA-68, SA-70, SA-72, SA-93, SA-94, SA-95, SA-96, SA-97, SA-98, SA-99 or positive reference compound #1 were included individually in the reaction mixture, at appropriate concentrations, and the incubation mixture sampled 24 hours later, there was an absence of the minimum at 218 nm. Instead, a spectrum characteristic of random coil was exhibited (not shown). We conclude that these compounds prevent the conversion of natively unfolded α-synuclein to a n-sheet-rich structure. These results are summarized in Table 5. As a specific example, compound SA-57 resulted in nearly complete inhibition when used at test compound:α-synuclein molar ratios ?0.05:1, with a calculated IC 50 of 0.026 moles of compound per mole of α-synuclein ( FIG. 5 ), whereas the negative reference compound did not significantly inhibit 3-sheet formation at any of the tested molar ratios (not shown). Nearly all of the compounds that inhibited α-synuclein β-sheet formation did so at less than equimolar ratios relative to α-synuclein (i.e. IC 50 molar ratios <1), although some compounds (for example, SA-99; IC 50 =2.08) required higher concentrations in order to markedly inhibit α-synuclein β-sheet formation (Table 5). Taken together, these results indicate that these SA compounds show potent inhibition and prevention of α-synuclein aggregation a hallmark of the synucleinopathies such as Parkinson's disease.
[0000]
TABLE 5
SA compounds prevent/inhibit β-sheet coataining α-synuclein
aggregates as assessed by circular dichroism spectroscopy.
SA #
IC 50 (mole ratio)
Max % Inhibition
54
0.55
100
55
0.055
100
57
0.026
100
58
0.36
94
59
0.75
99
61
0.78
95
62
0.54
88
64
0.56
100
67
0.41
100
68
0.6
100
70
0.25
92
72
0.27
100
93
0.38
91
94
0.22
95
95
0.68
97
96
0.13
100
97
not determined
100
98
0.08
100
99
2.08
98
Positive Ref. #1
0.04
100
Negative Ref.
not determined
none detected
Example 40
Compounds Provided Herein Bind with High Affinity to Parkinson's Disease α-Synuclein Fibrils
[0258] The compounds prepared in the preceding examples were found to bind with high affinity to α-synuclein aggregates/fibrils that are found in the hallmark Lewy Bodies of Parkinson's disease. In order to assess relative binding affinities of the test compounds for aggregated α-synuclein, competition assays were set up with a radiolabeled molecule already known to bind to α-synuclein fibrils and non-radiolabeled test compounds. In order to induce its aggregation, α-synuclein was incubated in phosphate buffered saline (PBS, pH 7.4) at 37° C. for three days with shaking (1,400 rpm). Competitive binding assays were carried out in 12×75 mm borosilicate glass tubes. The reaction mixture contained 100 μL, of α-synuclein aggregates (0.5-1 μg), [ 3 H] positive reference compound #1 (100-200 nM diluted in PBS) and 50 μl, of competing compounds (10 −5 -10 −9 M, diluted serially in PBS containing 0.1% bovine serum albumin) in a final volume of 0.25 ml. Non-specific binding was defined in the presence of cold positive reference compound #1 (50 μM) in the same assay tubes. The mixture was incubated for 120 min at 37° C., and the bound and the free radioactivity were separated by vacuum filtration through Whatman GF/B filters using a Brandel M-24R cell harvester, followed by washing with PBS buffer three times. Filters containing the bound [ 3 H] positive reference compound #1 were assayed for radioactivity in a liquid scintillation counter (Beckman LS6500). IC 50 values were determined by a non-linear, least squares regression analysis. Inhibition constants (Ki) values were calculated using the equation of Cheng and Prusoff (Cheng et al., Biochemical Pharmacology 22:3099-3108, 1973) using the observed IC 50 of the tested compound, the concentration of radioligand employed in the assay, and the value for the Kd of the ligand (600 nM).
[0259] The results from these experiments are reported in Table 6. As an example, SA-64 binds with high affinity to α-synuclein fibrils (Ki=89 nM) but does not show significant binding affinity for the amyloid-β peptide of Alzheimer's disease (not shown). Similarly, SA-58 and SA-57 bind with high affinity to α-synuclein aggregates, with binding constants (Ki) of 105 nM and 124 nM, respectively. The increased binding affinity (by 4-5-fold) of SA-57 and SA-58, relative to positive reference molecule #1 represents a significant improvement in binding to α-synuclein aggregates for these new molecules. Taken together, these results indicate that SA compounds bind to varying degrees to the α-synuclein aggregates, a hallmark of synucleinopathies such as Parkinson's disease.
[0000]
TABLE 6
SA compounds bind to α-synuclein aggregates as
measured by an in vitro competition binding assay.
SA #
K i (nM)
52
1260
53
813
54
1640
55
370
57
124
58
105
59
697
61
3100
62
506
63
283
64
89
66
135
67
466
68
697
69
765
70
659
72
270
76
219
78
330
79
537
82
177
83
330
84
639
86
224
87
2000
88
970
89
1200
90
1700
94
1100
95
890
96
1350
Positive reference #1
532
negative reference #1
no binding
negative reference #2
>10000
Example 41
Use of Recombinant Tau Repeat Domain for In Vitro Screening of Tau Aggregation Inhibitors
[0260] During in vitro screening for identification of tau aggregation inhibitors, we found that under the same experimental conditions, formation of paired helical filaments (PHFs) from commercially-purchased full-length tau protein (e.g. Tau441; rPeptide) was much slower (>11 days) than that from the tau repeat domain (TauRD; containing Q244-E372 of Tau441) (≧24 hours). Because of the remarkably short turn-around time and common aggregation properties, we used TauRD for in vitro drug screening to identify tau aggregation inhibitors [Barghorn S, Biemat J, and Mandelkow E, Purification of recombinant tau protein and preparation of Alzheimer-paired helical filaments in vitro. Methods Mol Biol, 2005. 299: p. 35-51]. Since the TauRD protein is not commercially available, we produced our own protein for this study. A cDNA fragment coding for the human TauRD (Q244-E372 of Tau441) was cloned into a bacterial expression vector and the construct was then expressed in E. Coli . The recombinant TauRD protein was then purified by heat-stability treatment and cation exchange chromatography as described [Barghorn, et al.,] with minor modifications. Using this method, we achieved a protein yield of 10 mg per liter of bacterial culture, with >95% purity. Aggregation and PHF formation of purified TauRD were evaluated and validated by independent assays including Thio S fluorometry, CD spectroscopy and electron microscopy (Data not shown). The results consistently demonstrate that TauRD (10 μM) is able to form Thio S-positive, 0-sheet-containing PHFs when incubated with an equal concentration of heparin, at 37° C. (with shaking at 800-1000 rpm for day).
Example 42
Identification of Novel Tau Aggregation Inhibitors by Thioflavin S Fluorometry Screening
[0261] The Thio S fluorometry assay as a primary screening method to identify tau protein aggregation inhibitors from our small molecule library. Aggregated tau fibrils were prepared in the presence of equimolar ratios of TauRD and heparin (10 μM each) in 20 mM Na-phosphate buffer, pH7.4. The reaction mixture was incubated at 37° C. with shaking (800-1000 rpm) for 22-24 hr (or for 3 days). In the Thio S inhibition assays, test compounds at 0, 0.1, 1, 10 and 100 μM were added at time 0 into the reaction containing TauRD and heparin. The same reaction mixture (+/− increasing concentrations of compounds) but without TauRD were also set up in parallel to serve as background controls. For all test compounds background fluorescence readings were very low, usually <5% of those of the TauRD-containing wells. For each compound, the IC 50 was calculated using Prism version 5 software (GraphPad Software) by nonlinear regression [(Log [inhibitor] vs. normalized response; variable slope)]. In initial screening, 20 test compounds demonstrated a broad range of activities for inhibiting tau protein fibril formation: IC 50 values ranged from ˜5 μM to infinity (i.e. no activity at all). The results suggested that the inhibitory activities were structure specific. The Thio S screening results are summarized in Table 7 (in which the reactions were incubated for 22 hours).
[0000]
TABLE 7
SA compounds inhibit tau protein fibril formation
as measured by Thioflavin S fluorometry.
Compounds
ThioS (IC 50 , μM)
SA-97
5.20
SA-54
7.34
SA-95
9.02 ± 4.66 (n = 2)
SA-63
10.08 ± 0.56 (n = 2)
SA-57
10.24
SA-61
12.54 ± 1.24 (n = 2)
SA-64
17.61
SA-96
21.21
SA-94
21.44
SA-99
24.70
SA-52
32.83
SA-68
33.96
SA-98
78.51
SA-70
117.00
SA-59
211.10
SA-72
290.20
SA-67
3941.00
SA-62
no inhibition
SA-55
no inhibition
SA-60
no inhibition
Example 43
Select Compounds Also Inhibit Tau Protein Formation of β-Sheet Secondary Structures Characteristic of Neurofibrillary Tangles as Determined by Circular Dichroism Spectroscopy
[0262] CD spectroscopy was also performed to determine each compound's potency in inhibiting β-sheet secondary structure in TauRD under aggregation-prone conditions. The CD spectroscopy and Thio S assays were typically analyzed in parallel from the same sample preparation in order to correlate the results from two independent assays. CD spectra were taken from the samples containing +/−TauRD with increasing concentrations of compounds, and collected at 25° C. on a JASCO Model J-810 Spectropolarimeter. To determine compound inhibitory potency, we established a semi-quantitative scoring system to illustrate TauRD conformational changes on CD spectra explained below. Since CD spectra reflect a total population of secondary structures (including random coil, β-sheet, and various intermediate conformers) of TauRD proteins under a given condition, the CD scores were established based on (1) the CD spectra derived from TauRD mixtures with different ratios of random coil/β-sheet; (2) time-dependent conformational changes of TauRD. CD analysis revealed that non-aggregated TauRD proteins in solution (at time 0 in the presence of heparin, or at various times of incubation in the absence of heparin) showed spectra with ellipticity minima near 195 nm, characteristic of largely random coil structures (not shown). In contrast, aggregated and fibrillar TauRD showed spectra with minima near 218 nm, characteristic of β-sheet secondary structure (not shown). Our CD analysis studies confirmed some of our compounds that could inhibit formation of tau protein β-sheet structure.
[0000]
TABLE 8
SA compounds prevent/inhibit β-sheet containing tau
protein as assessed by circular dichroism spectroscopy.
Compounds
CD
SA-97
++
SA-54
−
SA-95
+
SA-63
+
SA-57
−
SA-61
+
SA-64
−
SA-96
−
SA-94
−
SA-99
+
SA-52
+
SA-68
No data
SA-98
No data
SA-70
No data
SA-59
−
SA-72
−
SA-67
n/t
SA-62
n/t
SA-55
−
SA-60
n/t
[0263] Table 8 summarizes data from aggregated TauRD proteins in the presence of various SA-compounds where the CD score of ‘−’ indicates that the CD spectrum is similar to that of no compound controls with ellipticity minima at 218 nm (β-sheet) and ‘+’ indicates that the Minima remained at 218 nm but with a reduced magnitude (intermediate conformers) and ‘++’ indicates that the minima shifted to between 195-218 nm (intermediate conformers)
Example 44
Compositions of Compounds Provided Herein
[0264] The compounds provided herein, as mentioned previously, are desirably administered in the form of pharmaceutical compositions. Suitable pharmaceutical compositions, and the method of preparing them, are well-known to persons of ordinary skill in the art and are described in such treatises as Remington: The Science and Practice of Pharmacy , A. Gennaro, ed., 20th edition, Lippincott, Williams & Wilkins, Philadelphia, Pa. Representative compositions are as follows.
Oral Tablet Formulation
[0265]
[0000]
% w/w
Compound provided herein
10.0
Magnesium stearate
0.5
Starch
2.0
Hydroxypropylmethylcellulose
1.0
Microcrystalline cellulose
86.5
[0266] The ingredients are mixed to homogeneity, then granulated with the aid of water, and the granulates dried. The granulate is then compressed into tablets sized to give a suitable dose of the compound. The tablet is optionally coated by applying a suspension of a film forming agent (e.g. hydroxypropylmethylcellulose), pigment (e.g. titanium dioxide), and plasticizer (e.g. diethyl phthalate), and drying the film by evaporation of the solvent. The film coat may comprise, for example, 2-6% of the tablet weight.
Oral Capsule Formulation
[0267] The granulate from the previous section of this Example is filled into hard gelatin capsules of a size suitable to the intended dose. The capsule is banded for sealing, if desired.
Softgel Formulation
[0268] A softgel formulation is prepared as follows:
[0000]
% w/w
Compound provided herein
20.0
Polyethylene glycol 400
80.0
[0269] The compound is dissolved or dispersed in the polyethylene glycol, and a thickening agent added if required. A quantity of the formulation sufficient to provide the desired dose of the compound is then filled into softgels.
Parenteral Formulation
[0270] A parenteral formulation is prepared as follows:
[0000]
% w/w
Compound provided herein
1.0
Normal saline
99.0
[0271] The compound is dissolved in the saline, and the resulting solution is sterilized and filled into vials, ampoules, and prefilled syringes, as appropriate.
Controlled-Release Oral Formulation
[0272] A sustained release formulation may be prepared by the method of U.S. Pat. No. 4,710,384, as follows:
[0273] One kilogram of a compound provided herein is coated in a modified Uni-Glatt powder coater with Dow Type 10 ethyl cellulose. The spraying solution is an 8% solution of the ethyl cellulose in 90% acetone to 10% ethanol. Castor oil is added as plasticizer in an amount equal to 20% of the ethyl cellulose present. The spraying conditions are as follows: 1) speed, 1 liter/hour; 2) flap, 10-15%; 3) inlet temperature, 50° C., 4) outlet temperature, 30° C., 5) percent of coating, 17%. The coated compound is sieved to particle sizes between 74 and 210 microns. Attention is paid to ensure a good mix of particles of different sizes within that range. Four hundred mg of the coated particles are mixed with 100 mg of starch and the mixture is compressed in a hand press to 1.5 tons to produce a 500 mg controlled release tablet.
[0274] The claimed subject matter is not limited in scope by the specific embodiments described herein. Indeed, various modifications of the specific embodiments in addition to those described will become apparent to those skilled in the art from the foregoing descriptions. Such modifications are intended to fall within the scope of the appended claims. Various publications are cited herein, the disclosures of which are incorporated by reference in their entireties.
|
Compounds and their pharmaceutically acceptable salts for treatment of tauopathies, such as Alzheimer's disease, Pick's disease, progressive supranuclear palsy, corticobasal degeneration, familial frontotemporal dementia/Parkinsonism linked to chromosome 17, amyotrophic lateral sclerosis/Parkinsonism-dementia complex, argyrophilic grain dementia, dementia pugilistic, diffuse neurofibrillary tangles with calcification, progressive subcortical gliosis and tangle only dementia.
| 2
|
RELATED APPLICATION DATA
[0001] This application is a Continuation-In-Part (CIP) of and claims priority of U.S. patent application Ser. No. 12/396,570, filed Mar. 3, 2009, which application is incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to methods, apparatus and products for filtering. In another aspect, the present invention relates to methods, apparatus and products for filtering streams of gas and/or liquids to remove solids and/or entrained liquids. In even another aspect, the present invention relates to methods, apparatus and products for filtering, utilizing a filter system in which that portion of the filter system more likely to accumulate filtrate is replaceable apart from that portion of the filter system which is less likely to accumulate filtrate. In even another aspect, the present invention relates to methods, apparatus and products for filtering, utilizing a two stage filter system in which that portion of the filter system in the first stage is more likely to accumulate filtrate is replaceable apart from that portion of the filter system in the second stage which is less likely to accumulate filtrate. In still another aspect, the present invention relates to a sealing arrangement for sealing the filter system in the sealing vessel.
[0004] 2. Brief Description of the Related Art
[0005] There are a number of applications in which it is necessary to remove solids or liquids from a gas stream, liquid stream, or multi-phase stream. As a non-limiting example, solid or liquid contaminants may be present in various gas or liquid streams of a refrigeration system. As another non-limiting example, gas pipelines many times contain solid or liquid contaminants.
[0006] Various apparatus and methods for removing solids and/or liquids from gas streams are well known. Quite commonly, gas filter elements are utilized for filtering dry gas streams as well as for separating solids and liquids from contaminated gas streams, or for coalescing entrained liquids from a gas stream. Often these types of gas filter elements are installed in multi-stage vessels, which are in turn installed in a gas pipeline, to perform these filtering functions.
[0007] There are a number of patents that relate to removing solids and/or liquids from gas streams, the follow of which are merely a small sampling.
[0008] U.S. Pat. No. 6,381,983, issued May 7, 2002, to Angelo et al., discloses an improved filter drier for a refrigeration system having a replaceable tubular filter element. A desiccant assembly is removably secured within a housing. The assembly includes a first and second molded desiccant, a hollow tubular perforated core located within said first and second molded desiccant, and a tubular filter located over said core.
[0009] U.S. Pat. No. 6,692,639, issued Feb. 17, 2004, to Spearman et al., discloses a conically shaped filtration and/or separation apparatus that is constructed from a stack of filters at least some of which are different sizes superposed above each, other, of said plurality of said filters in a fluid communicable relationship. A collapsible version of such conically shaped filter and/or separation apparatus is provided whereby a plurality of such filters are connected together using two piece interlocking or connecting end caps.
[0010] U.S. Pat. No. 6,858,067, issued Feb. 22, 2005, to Burns et al., discloses a filtration vessel for use with a rotary screw compressor that receives a compressed liquid/gas mixture from the compressor. The vessel utilizes a first stage vortex knockout region to remove bulk liquids through a circular motion that imposes centrifugal forces on the gas and liquid mixture. A coalescer region located above the vortex knockout region receives the relatively lighter fluids and separates any remaining entrained liquids from the fluids. The discharge from the filtration unit is an essentially liquid free compressed gas. The liquid discharge, in the case of lube oil can be recirculated to the compressor for another cycle.
[0011] U.S. Pat. No. 7,051,540, issued May 30, 2006, to TeGrotenhuis et al., discloses a wick-containing apparatus capable of separating fluids and methods of separating fluids.
[0012] U.S. Patent Application Publication No. 20070095746, published May 3, 2007 to Minichello et al., discloses an apparatus for filtering a gas or liquid stream such as a natural gas stream. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an inlet port at one extent and an outlet port at an opposite extent thereof. A partition located within the vessel interior divides the vessel interior into a first chamber and a second chamber. At least one opening is provided in the partition. A filter element is disposed within the vessel to extend from within the first chamber. A special seal structure formed of a resilient material and having conically shaped sidewalls is used to seal against one end of the filter element as well as forming a dynamic seal with the vessel riser in use.
[0013] U.S. Pat. No. 7,270,690, issued Sep. 18, 2007, to Sindel, discloses a separator vane assembly made up of a number of corrugated vanes that provide serpentine paths for the gas stream therethrough. As the gas stream flows through the serpentine paths, it changes direction and liquid in the gas stream impacts the surfaces of the vanes. The upstream section of the vane assembly has roughened surfaces to decrease the surface tension of the liquid, thereby causing the liquid to coalesce. The downstream section of the vane assembly has smooth surfaces so as to increase the surface tension of the liquid. The vane assembly is followed by filters, which capture the liquid that passes through the vane assembly. The vane assembly coalesces the liquid to enable the filters to operate more effectively.
[0014] U.S. Patent Application Publication No. 20070251876, published Nov. 1, 2007 to Krogue et al., discloses an apparatus for filtering a gas or liquid stream of impurities and to filter elements used in such an apparatus. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an input port at one extent and an output port at an opposite extent thereof. A partition located within the vessel interior divides the vessel interior into a first stage and a second stage. At least one opening is provided in the partition. A filter element is disposed within the vessel to extend from within the first stage. The filter element is made up of a carbon block filter media surrounded by a protective porous depth filter media.
[0015] U.S. Pat. No. 7,314,508, issued Jan. 1, 2008, to Evans, discloses a desiccant cartridge having a seal therearound for forming a proper seal between the cartridge and the canister of a receiver/dryer or accumulator assembly includes a cup extending along an axis having inner wall portion and outer wall portion connected to a transverse portion to define a chamber containing desiccant particles. A cap is secured to cup to secure the desiccant particles inside the chamber. The outer wall portion is provided with the seal that is composed of a flexible thermoplastic elastomer that is resistant to heat during welding shut of the canister.
[0016] U.S. Pat. No. 7,332,010, issued Feb. 19, 2008, to Steiner, discloses a two or three phase separator including a centrifugal separator, a demister (if a three phase separator), and a filter contained within a housing. The filter uses an outside-in flow principle. The filter includes an inner layer or a center core that defines a hollow interior. An outer layer is positioned adjacent and surrounding the inner layer. The outer layer includes a re-enforcement layer, a first particle filter layer, a coalescer layer, and a second particle filter layer. An access cover of the separator includes a cover plug, an actuator cam, a plurality of idler cam plates, and a plurality of mechanisms. The access cover cooperates with an opening and an annular groove in the housing to close off and seal the separator.
[0017] U.S. Pat. No. 7,344,576, issued Mar. 18, 2008, to TeGrotenhuis et al., discloses methods of separating fluids using capillary forces and/or improved conditions. The improved methods may include control of the ratio of gas and liquid Reynolds numbers relative to the Suratman number. Also disclosed are wick-containing, laminated devices that are capable of separating fluids.
[0018] Quite commonly in pipeline applications, it is not uncommon to see multi-stage vessels, as well as a multitude of other similar filtration vessels, that utilize solid or hollow core tubular elements, typically formed at least partially a porous filtration media. Non-limiting examples of such vessels include filtration equipment such as shown in U.S. Pat. No. 5,919,284, issued Jul. 6, 1999 or U.S. Pat. No. 6,168,647, issued Jan. 2, 2001, both to Perry, Jr. et al.
[0019] U.S. Pat. No. 5,919,284 discloses a gas filter separator coalescer and multi-stage vessel for separating liquids and solids from a gas stream and simultaneously coalescing liquids from the gas stream. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an input port at an extent and an output port at an opposite extent thereof. There is a partition located within the vessel interior that divides the vessel interior into a first stage and a second stage. There is at least one opening in the partition. A separator/coalescer filter element is disposed within the vessel to sealingly extend from within the first stage through the opening into the second stage. There is a chevron-type seal or an O-ring seal between the filter element and the opening. The input port, vessel interior, separator/coalescer filter element and output port together define a flow passage within the apparatus, whereby the gas stream flows into the first stage through the input port and through the filter element hollow core, thereby filtering solids out of the gas stream, separating liquids from the gas stream, and pre-coalescing liquids in the gas stream. The gas stream then flows along the hollow core past the partition and back through the filter element into the second stage, thereby coalescing liquids out of the gas stream, the gas stream then exiting the second stage through the outlet port.
[0020] U.S. Pat. No. 6,168,647 discloses an apparatus for separating liquids and solids from a gas stream and simultaneously coalescing liquids from the gas stream. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an input port at an extent and an output port at an opposite extent thereof. There is a partition located within the vessel interior that divides the vessel interior into a first stage and a second stage. There is at least one opening in the partition. A separator/coalescer filter element is disposed within the vessel to sealingly extend from within the first stage through the opening into the second stage. There is a chevron-type seal or an O-ring seal between the filter element and the opening. The input port, vessel interior, separator/coalescer filter element and output port together define a flow passage within the apparatus, whereby the gas stream flows into the first stage through the input port and through the filter element hollow core, thereby filtering solids out of the gas stream, separating liquids from the gas stream, and pre-coalescing liquids in the gas stream. The gas stream then flows along the hollow core past the partition and back through the filter element into the second stage through a louvered impingement baffle, thereby coalescing liquids out of the gas stream, the gas stream then exiting the second stage through the outlet port. The louvered impingement baffle conditions the gas stream to create a scrubbing effect on any fine mist exiting the separator/coalescer filter element.
[0021] With such equipment as disclosed in the U.S. Pat. No. 5,919,284 or 6,168,647, it is periodically necessary to perform maintenance on the filtration vessels, including replacement of the porous filter elements. This task is labor intensive and time consuming in situ because of the mounting structure used to mount the filter elements within the filtration vessel interior. Often, it is necessary to unscrew the end cap or nut to free the filter element from its associated structural mounting within the vessel interior. Not only is this time consuming, but the location of the mounting structure is sometimes inconvenient to access, making filter replacement a difficult or inconvenient chore. The same type of inconveniences is present in the initial filter installation process for new filtration vessels.
[0022] Specifically for filter systems of the type disclosed in U.S. Pat. No. 6,168,647, there are at least two reasons for the difficulty in removing the filter elements. First, the chevron seal is working against the removal direction when trying to remove the element. Second, since the filter element extends into the riser assembly, solids collect and pack into the riser assembly. Additionally, it is not uncommon to find damage to the downstream expanded metal support grid generally caused by the elements being shoved in too far.
[0023] In an effort to overcome the problems of the prior art, especially the deficiencies of U.S. Pat. No. 5,919,284 or 6,168,647, further development was advanced in U.S. Pat. No. 7,014,685, issued Mar. 21, 2006, and U.S. Pat. No. 7,108,738, issued Sep. 19, 2006, both to Burns et al. These two patents disclose an apparatus for filtering a gas or liquid stream such as a natural gas stream. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an input port at one extent and an output port at an opposite extent thereof. A partition located within the vessel interior divides the vessel interior into a first stage and a second stage. At least one opening is provided in the partition. A filter element is disposed within the vessel to extend from within the first stage. The filter element is easily mounted or removed from the vessel by rotating a J-slot engagement surface on the element which mates with a post provided on a mounting structure provided on the vessel partition.
[0024] However, in spite of the above advancements that have been made in overall filtration vessel design, there still exists a need in art for apparatus and methods for filtration.
[0025] There also exists a need in the art for apparatus and methods for improvements that simplify the process of mounting and replacing filter elements within the filtration vessel, thereby decreasing the cost of vessel installation and maintenance.
[0026] As a non-limiting example of a desired improvement, for filtration systems as disclosed in U.S. Pat. Nos. 5,919,284, and 6,187,647, the portion of the filter element positioned in the downstream stage is generally a lot cleaner than the portion of the filter element positioned in the upstream stage. However, with these filtration systems, the entire filter element is removed and replaced, even though the downstream portion of the filter may be readily further used.
[0027] These and other needs in the art will become apparent to those of skill in the art upon review of this specification, including its drawings and claims.
SUMMARY OF THE INVENTION
[0028] It is an object of the present invention to provide for apparatus and methods for filtration.
[0029] It is another object of the present invention to provide for apparatus and methods for improvements that simplify the process of mounting and replacing filter elements within the filtration vessel, thereby decreasing the cost of vessel installation and maintenance.
[0030] It is even another object of the present invention to allow the use of different removal efficiencies of filter elements in the first and second stages based on the application and/or operator's requirements.
[0031] These and other objects of the present invention will become apparent to those of skill in the art upon review of this specification, including its drawings and claims.
[0032] According to one embodiment of the present invention there is provided an apparatus for filtering a gas. The apparatus may include a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages. The apparatus also may include a filter element positioned in the opening comprising first member having a first connection end and a second member having a second connection end. This the first and second members may be connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, wherein at least a portion of the first member extends into the first stage, and at least a portion of the second member extends into the second stage, and wherein the first member is removable from the second member while the filter element is positioned in the opening.
[0033] According to another embodiment of the present invention, there is provided a method of operating a filtering apparatus. The filtering apparatus may comprise a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages, and further comprises a filter element positioned in the opening comprising a first member having a first connection end and a second member having a second connection end, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, wherein at least a portion of the first member extends into the first stage, and at least a portion of the second member extends into the second stage. The method may include separating the first member from the second member, while the filter element is positioned in the opening, thereby leaving at least a portion of the second member extending into the second stage.
[0034] According to even another embodiment of the present invention, there is provided a method of operating a filtering apparatus. The filtering apparatus may comprise a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages, and further comprises a filter element positioned in the opening comprising a first member having a first end and a second member having a second connection end, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end engage to provide the connection, wherein at least a portion of the first member extends into the first stage, and at least a portion of the second member extends into the second stage. The method may include replacing the first member with a replacement member.
[0035] According to still another embodiment of the present invention, there is provided an apparatus for filtering a gas. The apparatus may include a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages. The apparatus may also include a riser extending from the opening, said riser having a first end with a straight portion and a second end with a flared portion, with the straight portion positioned nearer the opening than the flared portion. The apparatus may also include a filter element having at least a portion positioned in the riser the filter element comprising a first member having a first connection end and a first filtering characteristic, and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, with the second connection end defining a first groove extending circumferentially around the second connection end with a first seal member residing in the first groove, wherein at least a portion of the second connection end is positioned in the riser with the first seal member engaging the straight portion of the riser, wherein at least a portion of the first member extends toward the first stage, and at least a portion of the second member extends toward the second stage, wherein the first member is removable from the second member while the filter element is positioned in the opening, and wherein the first filtering characteristic and the second filtering characteristic are the same or different.
[0036] According to yet another embodiment of the present invention, there is provided a method of operating a filtering apparatus, wherein the filtering apparatus comprises a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages, a riser extending from the opening, said riser having a first end with a straight portion and a second end with a flared portion, with the straight portion positioned nearer the opening than the flared portion, and further comprises a filter element positioned in the riser comprising a first member having a first connection end and a first filtering characteristic and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, with the second connection end defining a first groove extending circumferentially around the second connection end with a first seal member residing in the first groove, wherein at least a portion of the second connection end is positioned in the riser with the first seal member engaging the straight portion of the riser, wherein at least a portion of the first member extends toward the first stage, wherein at least a portion of the second member extends toward the second stage, and wherein the first filtering characteristic and the second filtering characteristic are the same or different, the method may include separating the first member from the second member, while the filter element is positioned in the riser, thereby leaving at least a portion of the second member extending into the second stage.
[0037] According to even still another embodiment of the present invention, there is provided a method of operating a filtering apparatus, wherein the filtering apparatus comprises a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages, a riser extending from the opening, said riser having a first end with a straight portion and a second end with a flared portion, with the straight portion positioned nearer the opening than the flared portion, and further comprises a filter element positioned in the riser comprising a first member having a first end and a first filtering characteristic and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end engage to provide the connection, with the second connection end defining a first groove extending circumferentially around the second connection end with a first seal member residing in the first groove, wherein at least a portion of the second connection end is positioned in the riser with the first seal member engaging the straight portion of the riser, wherein at least a portion of the first member extends toward the first stage, wherein at least a portion of the second member extends toward the second stage, and wherein the first filtering characteristic and the second filtering characteristic are the same or different, the method may include replacing the first member with a replacement member.
[0038] According to even yet another embodiment of the present invention, there is provided an apparatus for filtering a gas. The apparatus may include a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages. The apparatus may also include a riser extending from the opening, said riser having a first end with a straight portion and a second end with a flared portion, with the straight portion positioned nearer the opening than the flared portion. The apparatus may include a filter element having at least a portion positioned in the riser, the filter element comprising a first member having a first connection end and a first filtering characteristic, and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, with the second connection end defining first and second grooves extending circumferentially around the second connection end with a first seal member residing in the first groove and a second seal member residing in the second groove, wherein at least a portion of the second connection end is positioned in the riser with both the first and second seal members engaging the straight portion of the riser, wherein at least a portion of the first member extends toward the first stage, and at least a portion of the second member extends toward the second stage, wherein the first member is removable from the second member while the filter element is positioned in the opening, and wherein the first filtering characteristic and the second filtering characteristic are the same or different.
[0039] According to still even another embodiment of the present invention, there is provided a filter system that may include a riser having a first end with a straight portion and a second end with a flared portion. The system may include a filter element having at least a portion positioned in the riser the filter element comprising a first member having a first connection end and a first filtering characteristic, and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, with the second connection end defining a first groove extending circumferentially around the second connection end with a first seal member residing in the first groove, wherein at least a portion of the second connection end is positioned in the riser with the first seal member engaging the straight portion of the riser, wherein the first member is removable from the second member while the filter element is positioned in and remains in the riser, and wherein the first filtering characteristic and the second filtering characteristic are the same or different.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] The following drawings illustrate some of the many possible embodiments of this disclosure in order to provide a basic understanding of this disclosure. These drawings do not provide an extensive overview of all embodiments of this disclosure. These drawings are not intended to identify key or critical elements of the disclosure or to delineate or otherwise limit the scope of the claims. The following drawings merely present some concepts of the disclosure in a general form. Thus, for a detailed understanding of this disclosure, reference should be made to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements have been given like numerals.
[0041] FIG. 1 is a schematic representation of one non-limiting embodiment of a filtration system of the present invention.
[0042] FIG. 2 is a schematic representation of a filter element of the present invention.
[0043] FIG. 3 shows engaging member 139 of first filter member 124 resides in slot 136 of second filter member 125 .
[0044] FIG. 4 shows first filter member 124 and second member 125 have been twisted relative to each other to allow engaging member 139 to move in slot 136 toward slot opening 137 to allow for disengagement.
[0045] FIG. 5 shows first filter member 124 and second member 125 have been further twisted relative to each other, such that engaging member 139 is shown aligned in slot opening 137 to allow for disengagement.
[0046] FIG. 6 shows first filter member 124 and second member 125 have been moved away from each other, such that engaging member 139 is shown moving though slot opening 137 to allow for disengagement.
[0047] FIG. 7 shows first filter member 124 and second member 125 have been moved away from each other, such that engaging member 139 is shown moved completely through slot opening 137 and filter members 124 and 125 are disengaged.
[0048] FIGS. 8-10 show slightly different views of filter 120 , showing filter members 124 and 125 disengaged.
[0049] FIG. 11 is an illustration of a non-limiting embodiment of the present invention, showing first filtration element 124 , second filtration element 125 , vessel partition 108 defining passage 111 , and filtration receiving tube 300 having a flared portion 301 and a straight portion 302 .
[0050] FIG. 12 is a schematic representation of receiving tube 300 and second pair member 135 having a sealing member 307 engaging the flared portion 301 of tube 300 .
[0051] FIG. 13 is a schematic representation of receiving tube 300 and second pair member 135 having two sealing members 307 engaging the flared portion 301 of tube 300 .
[0052] FIG. 14 is a schematic representation of receiving tube 300 and second pair member 135 having a sealing member 308 engaging the straight portion 302 of tube 300 .
[0053] FIG. 15 is a schematic representation of receiving tube 300 and second pair member 135 having a sealing member 307 engaging the flared portion 301 of tube 300 , and sealing member 308 engaging the straight portion 302 of tube 300 .
[0054] FIG. 16 is a schematic representation of receiving tube 300 and second pair member 135 having two sealing members 308 engaging the straight portion 302 of tube 300 .
[0055] FIG. 17 is a schematic representation of receiving tube 300 and second pair member 135 having sealing member 309 engaging the outer lip portion 310 of tube 300 and bottom edge portion of member 135 A.
[0056] FIG. 18 is a schematic representation of receiving tube 300 and second pair member 135 (shown on end of filter member 125 ) not quite engaged with tube 300 . This non-limiting embodiment shows sealing members 307 , 308 and 309 , although other embodiments may have any combinations/numbers of these sealing members.
[0057] FIG. 19 shows receiving tube 300 engaged with second pair member 135 of FIG. 18 .
[0058] FIG. 20 is a schematic representation of receiving tube 300 and second pair member 135 having sealing member 309 engaging the outer lip portion 310 of tube 300 and bottom edge portion of member 135 A.
DETAILED DESCRIPTION OF THE INVENTION
[0059] In one aspect, the present invention provides a filtration filter. In another aspect, the present invention provides a filtration system that includes the filtration filter positioned within a filtration vessel. Any suitable type of filtration vessel may be utilized in the practice of the present invention, including certain filtration vessels as disclosed in any of U.S. Pat. Nos. 5,919,284, 6,187,647, 7,014,685, and 7,108,738. Depending upon the situation and operating conditions, suitable filtration vessels may include multi-stage vessel 11 as shown in FIG. 1 of U.S. Pat. No. 6,187,647, and filter vessel 13 as shown in FIG. 1 of U.S. Pat. No. 7,014,685, with the understanding that vessels 11 and 13 will include the filtration filter as disclosed herein, and be adapted to receive such filter.
[0060] Referring now to FIG. 1 , there is shown a schematic representation of one non-limiting embodiment 100 of the filtration system of the present invention. In very simple terms, the filtration system of the present invention may include a filtration vessel 102 having a first stage 104 and a second stage 105 . A partition 108 positioned within filtration vessel 102 divides the volume of filtration vessel 102 into first stage 104 and second stage 105 . The present invention anticipates that in some non-limiting embodiments, filtration vessel may comprise two vessels that are joined together, one vessel forming the first stage, and one vessel forming the second stage, with the abutted walls of each vessel serving as the partition, or perhaps the two vessels will share a common wall serving as the partition.
[0061] Partition 108 defines at least one passage 111 allowing for liquid communication between first stage 104 and second stage 105 . Within each of passages 111 will reside a filtration filter 120 . This filter 120 includes at least two distinct parts, first filtration member 124 and second filtration member 125 . Filter member 120 may in some embodiments be a hollow core filtration filter. In some non-limiting embodiments, at least a portion of first filtration member 124 will extend into vessel first stage 104 , and at least a portion of first member 124 will extend into vessel second stage 105 . In some non-limiting embodiments, none of first filtration member 124 will extend into vessel second stage 105 . In even other embodiments, none of the second filtration member 125 will extend into vessel second stage 105 . In even further non-limiting embodiments, an additional filter element, such as a liquid impingement baffle, will be placed over the second filtration member 125 .
[0062] It should be understood that first filtration member 124 and second filtration member 125 may provide the same or different filtering, that is, the filtering characteristic of the first and second filtration members 124 and 125 may be the same or different. As a non-limiting example, first filtration member 124 may have a first filtering characteristic wherein it removes larger particles and allows smaller particles to be removed by filtration member 125 having a second filtering characteristic wherein it removed smaller particles. It should also be understood that when multiple filter members 120 are utilized, each of the multiple filter members 124 and 125 may be the same or different. As a non-limiting example, various same and/or different filter members 120 may be utilized based on the geometry of the arrangement of the filter members 120 , based on the geometry of the vessel 102 , and/or based on any other operating parameter or physical property of the material being filtered. It should also be understood that filter member 120 may also include multiple stages that align with multiple stages in a vessel 102 . The filter member 120 may include mating pairs 130 at the interface of one or more or all of the interfaces between stages, which mating pairs 130 may be the same or different, and this filter member 120 may be disconnectable at one or more the mating pairs 130 .
[0063] Filtration vessel 102 further includes an inlet port 184 in fluid communication with vessel first stage 104 . Filtration vessel 102 even further includes an outlet port 185 in fluid communication with vessel second stage 105 .
[0064] Gas flow, indicated by the “G” labeled arrows, is through inlet port 184 and into vessel first stage 104 , through the filter wall of filter member 124 , through the hollow core of filter member 124 , into the hollow core of filter member 125 , out through the wall of filter member 125 , through the second stage 105 , and finally exiting through outlet 185 .
[0065] Referring additionally to FIG. 2 , there is shown a schematic representation of filter element 120 of the present invention. Referring even additionally to FIGS. 3-10 , there is illustrated various views of filter element 120 showing first member 124 and second member 125 in various states of connection. Filter member 124 and filter member 125 are joined by a mating pair 130 having a first pair member 134 at end 124 A of filter member 124 , and a second pair member 135 at end 125 A of filter member 125 . In some embodiments, the mating pair 130 will comprise male and female connector members. It should be understood that first pair member 134 may comprise either a male or female connector member, with second pair member 135 comprising the complimentary mating female or male connector member. In most embodiments, a female-male arrangement for the first and second pair members 134 and 135 will be considered equivalent to a male-female arrangement. This mating pair 130 must sufficiently join filter member 124 and 125 together so as to endure the hardships of the filtration operation, but must allow disconnecting of filter member 124 to allow for removal of such filter member 124 . As non-limiting examples, mating pair 130 may connect by snapping, bolting, friction fitting, interlocking, engaging, coupling, hook/looping, adhering, adhesion with a time released adhesive, adhesion with a solvent releasing adhesive, magnetic coupling, locking, threadably engaging, and the like.
[0066] In FIG. 3 , engaging member 139 of first filter member 124 resides in slot 136 of second filter member 125 . As shown, engaging member 139 resides in end 138 of slot 136 . Generally, twisting/untwisting of members 124 and 125 relative to each other would lock engaging member 139 in place at end 138 or could move it toward slot opening 137 for disengagement. As a non-limiting embodiment, end 138 of slot 136 may be shaped (for example tapered) to provide a friction fit of engaging member 139 , or the surfaces of slot 136 at end 138 may be textured/roughened to engage textured/roughened surfaces of engaging member 139 . Untwisting them will reverse the process and allow for the members to be separated.
[0067] Referring now to FIG. 4 , first filter member 124 and second member 125 have been twisted relative to each other to allow engaging member 139 to move in slot 136 toward slot opening 137 to allow for disengagement.
[0068] Referring now to FIG. 5 , first filter member 124 and second member 125 have been further twisted relative to each other, such that engaging member 139 is shown aligned in slot opening 137 to allow for disengagement.
[0069] Referring now to FIG. 6 , first filter member 124 and second member 125 have been moved away from each other, such that engaging member 139 is shown moving though slot opening 137 to allow for disengagement.
[0070] Referring now to FIG. 7 , first filter member 124 and second member 125 have been moved away from each other, such that engaging member 139 is shown moved completely through slot opening 137 and filter members 124 and 125 are disengaged.
[0071] FIGS. 8-10 show slightly different views of filter 120 , showing filter members 124 and 125 disengaged.
[0072] In methods of the present invention, with filter element positioned within a filter vessel 102 , filter member 124 may be separated from filter member 125 , removed from vessel 102 , and then replaced with a new filter member.
[0073] Referring now to FIG. 11 , there is illustrated a non-limiting embodiment of the present invention, showing first filtration element 124 , second filtration element 125 , vessel partition 108 defining passage 111 connecting first stage 104 and second stage 105 , and filtration receiving tube 300 having a flared portion 301 and a straight portion 302 . End 125 A of second filtration element 125 is inserted into filtration receiving tube 300 with mating pair member 135 on the other end of element 125 engaging flared portion 301 , with sealing members 307 and 308 providing sealing against tube 300 . In some embodiments, all of mating pair member 135 may be inserted into tube 300 . In other embodiments, a first portion of mating pair member 135 is inserted into tube 300 , with a second portion of mating pair member 135 not inserted into tube 300 . This second portion of mating pair member 135 is generally larger than tube 300 cross-sectional area and actually wedges against end of tube 300 and is unable to be inserted into tube 300 . First filtration element 124 engages second filtration element 125 as described above, with mating pair members 134 and 135 engaging. Mating pair member 135 may have groove(s) 307 A for receiving sealing member(s) 307 and groove(s) 308 A for receiving sealing member(s) 308 . In some embodiments, it is possible or second filtration element 125 to reside in tube 300 and not extend past partition 108 , although for many embodiments, filtration element 125 will extend past partition 108 and into second stage 105 . Regarding passage 111 , in various non-limiting embodiments, it may be regarded as being defined by vessel partition 108 with filtration receiving tube 300 positioned therein, or passage 111 may be regarded as defined by receiving tube 300 which passes through vessel partition 108 , or passage 111 may be in communication with the end of receiving tube 300 with tube 300 abutted against partition 108 , or an integral unit may define partition 108 , filtration receiving tube 300 and passage 111 , or any combination thereof.
[0074] The filtration receiving tube 300 is generally a riser member that is affixed to vessel partition 108 positioned generally over passage 111 . In many embodiments, vessel partition 108 will define numerous passages 111 , and risers will generally be positioned over each of the numerous passages 111 . Certainly, it is possible to construct a filtration vessel 102 with a vessel partition 108 having integral risers, rather than having risers that are subsequently affixed. However, very commonly commercial filtration vessels generally includes riser members as the filtration receiving tube 300 that have been affixed, usually by welding techniques, over each of the passages 111 on vessel partition 108 .
[0075] These risers 300 will generally have a slightly flared end 301 . While not being limited by theory, applicants believe that in some (but not all) instances, the flared portion 301 may provide a less consistent, less reliable sealing surface than the straight portion 302 .
[0076] While not wishing to be limited by theory, applicants believe that problems in sealing may be caused by at least two mechanisms. In some instances this flared portion 301 is not quite as round as the straight portion 302 , and when engaged with round member 135 some portions of the seal around member 135 will engage more or less depending upon the larger or smaller gap between the less than round flared portion 301 and the more round member 135 . Thus, various non-limiting embodiments of the present invention provide for 2 or more sealing elements in the flared portion, or at least one sealing element in the straight portion, or at least one sealing element in each of the flared and straight portions. In other instances, a local surface inconsistency may cause sealing issue. These problems with less than round flared portions 301 and surface inconsistencies may be addressed by positioning the seal member in the straight portion 302 as it is likely to be more round and/or by using redundant sealing members positioned either in the flared or straight portions.
[0077] Sealing member 307 is understood to be a sealing element that engages the flared portion 301 of filtration receiving tube 300 , and sealing member 308 is understood to be a sealing element that engages the straight portion 302 of filtration receiving tuber 300 . While both sealing members 307 and 308 are shown, it is understood that second filtration element 125 may have only sealing member(s) 307 , or only sealing member(s) 308 , or any numbers of both sealing members 307 and 308 .
[0078] Sealing members 307 and 308 may be any suitable sealing member/material that will provide suitable sealing between member 125 and riser 300 . A non-limiting examples of a suitable sealing member includes a packing joint, which is a mechanical gasket with a suitable cross-section, designed to be seated in grooves 307 / 308 and compressed between riser 300 and mating pair member 135 upon insertion and seating of member 125 into riser 300 .
[0079] Non-limiting examples packing joints suitable for use as the sealing means include those having any suitable cross-sectional shapes, include round, oval, X, square, triangular, U, or any other regular or irregular geometric shape as the cross-section. Non-limiting embodiments of the present invention may utilize U seals.
[0080] Referring additionally to FIG. 12 , there is shown a schematic representation of receiving tube 300 and second pair member 135 having a sealing member 307 engaging the flared portion 301 of tube 300 .
[0081] Referring additionally to FIG. 13 , there is shown a schematic representation of receiving tube 300 and second pair member 135 having two sealing members 307 engaging the flared portion 301 of tube 300 .
[0082] Referring additionally to FIG. 14 , there is shown a schematic representation of receiving tube 300 and second pair member 135 having a sealing member 308 engaging the straight portion 302 of tube 300 .
[0083] Referring additionally to FIG. 15 , there is shown a schematic representation of receiving tube 300 and second pair member 135 having a sealing member 307 engaging the flared portion 301 of tube 300 , and sealing member 308 engaging the straight portion 302 of tube 300 .
[0084] Referring additionally to FIG. 16 , there is shown a schematic representation of receiving tube 300 and second pair member 135 having two sealing members 308 engaging the straight portion 302 of tube 300 .
[0085] Referring additionally to FIG. 17 there is shown is a schematic representation of receiving tube 300 and second pair member 135 having sealing member 309 engaging the outer lip portion 310 of tube 300 and bottom edge portion of member 135 A.
[0086] Referring additionally to FIG. 18 there is shown a schematic representation of receiving tube 300 and second pair member 135 (shown on end of filter member 125 ) not quite engaged with tube 300 . This non-limiting embodiment shows sealing members 307 , 308 and 309 , although other embodiments may have any combinations/numbers of these sealing members. Moving forward, FIG. 19 shows receiving tube 300 engaged with second pair member 135 of FIG. 18 .
[0087] Referring additionally to FIG. 20 there is shown is a schematic representation of receiving tube 300 and second pair member 135 having sealing member 309 engaging the outer lip portion 310 of tube 300 and bottom edge portion of member 135 A. While similar to FIG. 17 , this sealing member 309 is shaped to drape over outer lip portion 310 and drape down onto the tapered and even possibly the straight portion of tube 300 .
[0088] All of the patents and applications cited in this specification, are herein incorporated by reference.
[0089] It should be understood that while the present invention has been illustrated mainly by reference to filtration of a gas stream, it finds utility in the filtration of gas streams, liquid streams, and gas/liquid streams.
[0090] The present disclosure is to be taken as illustrative rather than as limiting the scope or nature of the claims below. Numerous modifications and variations will become apparent to those skilled in the art after studying the disclosure, including use of equivalent functional and/or structural substitutes for elements described herein, use of equivalent functional couplings for couplings described herein, and/or use of equivalent functional actions for actions described herein. Any insubstantial variations are to be considered within the scope of the claims below.
|
A device for filtering a gas stream, having a vessel partitioned into a first stage and a second stage, with an opening between stages. A filter element is positioned in the opening, with ends of the filter element extending into the first and second stages. The first member is removable from the second member while the filter element is positioned in the opening, to allow for replacement with a new clean member.
| 1
|
[0001] Priority is claimed under 35 U.S.C. §119 to Japanese Patent Application No. 2007-099879 filed Apr. 5, 2007, which is hereby incorporated by reference in its entirety, including the specification, drawings and claims.
BACKGROUND
[0002] The present invention relates to a medium transporting unit that transports a plate-like medium such as a CD or a DVD and a medium processing apparatus having the medium transporting unit.
[0003] In recent years, medium processing apparatuses such as disc dubbing apparatuses that record data on mediums such as plural blank CDs or DVDs and CD/DVD publishers that can produce and publish a medium by performing a data recording operation and a label printing operation were used. Such a kind of medium processing apparatus was known which has a drive for driving data on a medium, a printer for performing a printing operation on a label surface of the medium, and a medium transporting unit for holding and transporting the medium to the drive or the printer (for example, see Patent Document 1).
Patent Document 1: Japanese Patent Publication No. 2006-202379A
[0005] Blank mediums that have not been subjected to a recording process and the like are received and stacked in the medium stacker. Adjacent mediums in the stacker may be adhered to each other due to an adhesive force. Accordingly, at the time of picking up the uppermost medium, the medium just-below the uppermost medium (that is, the second medium) may be adhered and lifted up together with the uppermost medium.
[0006] When two mediums are transported in a state where they are adhered to each other, a problem may be caused in a drive to which the two mediums are transported. In addition, holding failure of the uppermost medium may easily occur.
SUMMARY
[0007] Accordingly, an object of at least one embodiment of the invention is to provide a medium transporting unit that can satisfactorily transport only a single medium to be held and a medium processing apparatus having the medium transporting unit.
[0008] In order to accomplish the above-mentioned object, according to an aspect of at least one embodiment of the invention, there is provided a medium transporting unit for transporting a top medium from a plurality of plate-shaped media accommodated in a stacker in a stacked manner, the medium transporting unit comprising: a holding mechanism operable to hold the top medium; and a transport arm provided with the holding mechanism, wherein the transport arm is provided with a separation mechanism operable to separate a second medium positioned just below the top medium which is held by the holding mechanism.
[0009] Accordingly, even when the second medium positioned just below the top medium is adhered to the top medium, it is possible to pick up and transport only the top medium without any holding failure by separating the second medium.
[0010] The separation mechanism may include a separation member having a contact piece which is movable so as to come in contact with an inner peripheral surface of a center hole formed on the second medium and being operable to move the contact piece to move the second medium in a radial direction thereof.
[0011] According to this configuration, by moving the separation member to allow the contact piece to protrude at the time of the holding and lifting up the top medium, it is possible to easily separate the second medium adhered to the top medium.
[0012] The medium transporting unit may further comprising a lift mechanism operable to lift up and down the transport arm.
[0013] The separation mechanism may include a moving mechanism operable to move the separation member so that the contact piece is located at a separation position where the contact piece comes in contact with the inner peripheral surface of the center hole to move the second medium in the radial direction thereof when the lift mechanism lifts up the transport arm and the contact piece is located at a waiting position where the contact piece does not come in contact with the inner peripheral surface of the center hole when the lift mechanism lifts down the transport arm.
[0014] According to this configuration, it is possible to separate the second medium by moving the separation member, without providing a specific driving mechanism.
[0015] The moving mechanism may include a rack extending in a vertical direction and a pinion engaging with the rack; and the moving mechanism may move the separation member by a rotational force of the pinion which is rotated by the rack when the lift mechanism lifts up and down the transport arm.
[0016] According to this configuration, it is possible to allow the contact piece to protrude and retract in the diameter direction by lifting up and down the transport arm to move the separation member.
[0017] The moving mechanism may include a clutch gear rotatable by a predetermined angle when the lift mechanism lifts up and down the transport arm.
[0018] According to this configuration, at the time of picking up the held top medium by lifting up the transport arm, the separation member is moved by a predetermined distance by the clutch gear rotated by a predetermined angle at the time of lifting up the transport arm and it is thus possible to separate the second medium by allowing the contact piece to protrude outwardly in the radial direction by a predetermined distance.
[0019] On the other hand, at the time of lifting down the transport arm so as to hold the medium or to place the held top medium at a predetermined position, the separation member is moved in the opposite direction by a predetermined distance by the clutch gear reversely rotated by a predetermined angle at the time of lifting down the transport arm, and it is thus possible to insert the contact piece, thereby preventing the contact piece from interfering with the medium to be held or the medium to be placed.
[0020] The separation member may include a front lever portion having the contact piece and a rear lever portion moved by the moving mechanism. Such a configuration is effective for making the very small operation piece movable.
[0021] The separation member may include an elastic member operable to transmit a moving force applied to the rear lever portion to the front lever portion so that the contact piece applies an acting force to the second medium; and when a counteracting force from the second medium is more than a force of the elastic member, the elastic member may deform so as not to transmit the moving force to the front lever portion. With this configuration, the contact piece is prevented from being damaged before separating the second medium from the top medium due to the very strong adhesion therebetween.
[0022] According to another aspect of at least one embodiment of the invention, there is provided a medium processing apparatus comprising: the above medium transporting unit; and a media drive having at least one of a function for writing data on the transported medium which is transported by the medium transporting unit and a function for reading data on the transported medium.
[0023] With this configuration, it is possible to satisfactorily transport only a medium to be held, thereby enhancing the processing reliability of the medium processing apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein:
[0025] FIG. 1 is a perspective view illustrating an appearance of a publisher (medium processing apparatus);
[0026] FIG. 2 is a perspective view illustrating the front side of the publisher with a case removed from the publisher;
[0027] FIG. 3 is a perspective view illustrating the rear side of the publisher with the case removed from the publisher;
[0028] FIG. 4 is a perspective view illustrating a recording unit of the publisher;
[0029] FIG. 5 is a perspective view illustrating a medium transporting unit;
[0030] FIG. 6 is a perspective view illustrating a part of the medium transporting unit;
[0031] FIG. 7 is a perspective view illustrating a connection mechanism between a transport arm and a timing belt;
[0032] FIG. 8 is an enlarged perspective view illustrating the connection mechanism between the transport arm and the timing belt as viewed from the bottom;
[0033] FIG. 9 is a perspective view illustrating an internal structure of the transport arm;
[0034] FIG. 10 is a plan view illustrating the transport arm having held a medium as viewed from the bottom;
[0035] FIG. 11 is a sectional view illustrating a holding portion of the transport arm;
[0036] FIG. 12 is a perspective view illustrating a medium guide disposed in the holding portion of the transport arm;
[0037] FIG. 13 is a plan view illustrating the medium guide disposed in the holding portion of the transport arm;
[0038] FIG. 14 is a plan view of an arm base which is intended to explain a holding mechanism;
[0039] FIG. 15 is a perspective view illustrating holding claws of the holding mechanism;
[0040] FIG. 16 is an enlarged plan view illustrating the holding claws;
[0041] FIG. 17 is a plan view illustrating movements of pivoting plates and the holding claws;
[0042] FIG. 18 is a plan view illustrating movements of the pivoting plates and the holding claws;
[0043] FIG. 19 is a plan view illustrating movements of the pivoting plates and the holding claws;
[0044] FIG. 20 is a sectional view illustrating the holding claws;
[0045] FIG. 21 is a plan view of an arm base which is intended to explain a separation mechanism;
[0046] FIG. 22 is a front view illustrating the transport arm when the holding portion is viewed in a section;
[0047] FIG. 23 is a perspective view illustrating the separation mechanism;
[0048] FIG. 24 is a sectional view illustrating a pivoting mechanism disposed in the separation mechanism;
[0049] FIG. 25 is a plan view illustrating the pivoting mechanism disposed in the separation mechanism;
[0050] FIG. 26 is a plan view schematically illustrating the movement of the separation mechanism;
[0051] FIG. 27 is a plan view schematically illustrating the movement of the separation mechanism;
[0052] FIG. 28 is a graph illustrating a relation between a down stroke of a belt clip of the transport arm and a load acting on a medium; and
[0053] FIG. 29 is a flowchart illustrating a process of controlling a driving motor for lifting up and down the transport arm.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0054] Hereinafter, a medium transporting unit according to an embodiment of the invention and a medium processing apparatus having the medium transporting unit will be described with reference to the drawings.
[0055] In this embodiment, the invention is applied to a medium processing apparatus including a publisher.
[0056] As shown in FIG. 1 , the publisher 1 is a medium processing apparatus for recording data on a disc-like medium such as CD or DVD or printing an image on a label surface of the medium and has a case 2 having a substantially rectangular hexahedral shape. Shutters 3 and 4 which can be opened and closed slidably in the lateral direction are attached to the front surface of the case 2 . An operation surface 5 having display lamps, operation buttons, and the like arranged thereon is disposed at the left-upper end portion of the case 2 and a medium discharge port 6 is disposed at the lower end of the case 2 .
[0057] The right shutter 3 as viewed from the front side is a door which is opened and closed at the time of setting a blank medium MA not used or taking out the completed medium MB (see FIG. 2 ).
[0058] The left shutter 4 as viewed from the front side is opened and closed at the time of replacing an ink cartridge 12 of a label printer 11 (see FIG. 2 ). By opening the shutter 4 , a cartridge mounting section 14 (see FIG. 2 ) having plural cartridge holders 13 arranged in the vertical direction is exposed.
[0059] As shown in FIG. 2 , in the case 2 of the medium processing apparatus 1 , a blank medium stacker 21 as a medium storage unit in which plural blank mediums MA not yet used and not yet subjected to a data recording process can be stacked and a completed medium stacker 22 as a medium storage unit in which completed mediums MB are disposed vertically so that the center lines of the stored mediums are aligned with each other. The blank medium stacker 21 and the completed medium stacker 22 can be attached to and detached from predetermined positions shown in FIG. 2 .
[0060] The blank medium stacker 21 has a pair of arc-shaped frames 24 and 25 . Accordingly, the blank mediums MA can be received from the top and can be stacked coaxially in the stacker. The operation of receiving or replenishing the blank mediums MA in the blank medium stacker 21 can be simply performed by opening the shutter 3 and taking out the stacker.
[0061] The completed medium stacker 22 has the same structure and includes a pair of arc-shaped frames 27 and 28 . Accordingly, the completed mediums MB can be received from the top and can be stacked coaxially in the stacker.
[0062] The completed mediums MB (that is, mediums having been completely subjected to a data recording process and a label-surface printing process) may be taken out through the shutter 3 .
[0063] A medium transporting unit 31 is disposed in the back of the blank medium stacker 21 and the completed medium stacker 22 . In the medium transporting unit 31 , a chassis 32 is pivotably attached to a vertical guide shaft 35 vertically suspended between a base 72 and the top plate of the case 2 (see FIG. 5 ). A fan-shaped final-stage gear 109 is fixed to a horizontal supporting plate 34 of the chassis 32 (see FIG. 5 ). The transport arm 36 is supported by the chassis 32 so as to freely go up and down. The transport arm 36 can be lifted up and down along the vertical guide shaft 35 by a driving motor 37 which can be a step motor and can horizontally pivot about the vertical guide shaft 35 . A medium transported to the medium discharge port 6 by the medium transporting unit 31 can be taken out of the medium discharge port 6 .
[0064] Two medium drives 41 vertically stacked are disposed on a side of the upper and lower stackers 21 and 22 and the medium transporting unit 31 . A carriage 62 (see FIG. 4 ) of a label printer 11 is movably disposed below the medium drives 41 .
[0065] The medium drives 41 have medium trays 41 a that can move between a data recording position where data is recorded on a medium and a medium transferring position where the medium is transferred, respectively.
[0066] The label printer 11 has a medium tray 51 that can move between a printing position where an image is printed on a label surface of the medium and a medium transferring position where the medium is transferred (see FIG. 3 ).
[0067] In FIGS. 2 and 3 , a state where the medium tray 41 a of the upper medium drive 41 is drawn forward and located at the medium transferring position and a state where the medium tray 51 of the lower label printer 11 is located at the label printing position are shown. The label printer 11 is an ink jet printer and employs ink cartridges 12 of various colors (6 colors of black, cyan, magenta, yellow, light cyan, and light magenta in this embodiment) as the ink supply mechanism 71 . The ink cartridges 12 are mounted on the cartridge holders 13 of the cartridge mounting section 14 from the front side.
[0068] Here, a gap through which the transport arm 36 of the medium transporting unit 31 can be lifted up and down is formed between the pair of frames 24 and 25 of the blank medium stacker 21 and between the pair of frames 27 and 28 of the completed mediums stacker 22 . A clearance allowing the transport arm 36 of the medium transporting unit 31 to horizontally pivot and to be located just above the completed medium stacker 22 is opened between the blank medium stacker 21 and the completed medium stacker 22 . When the medium tray 41 a is pushed into the medium drive 41 , the transport arm 36 of the medium transporting unit 31 can be lifted down to access the medium tray 51 located at the medium transfer position. Accordingly, it is possible to transport the mediums to the individual elements by combination of the lifting operation and the pivoting operation of the transport arm 36 .
[0069] A waste stacker 52 for storing waste mediums MD is disposed below the medium transfer position of the medium tray 51 . For example, about 30 waste mediums MD can be stored in the waste stacker 52 . In a state where the medium tray 51 retreats from the medium transfer position above the waste stacker 52 to the data recording position, the waste mediums MD can be supplied to the waste stacker 52 by the use of the transport arm 36 of the medium transporting unit 31 .
[0070] Due to the above-mentioned configuration, the transport arm 36 of the medium transporting unit 31 can transport a medium such as a CD or DVD among the blank medium stacker 21 , the completed medium stacker 22 , the waste stacker 52 , the medium tray 41 a of the medium drive 41 , and the medium tray 51 of the label printer 11 .
[0071] As shown in FIG. 4 , the label printer 11 includes a carriage 62 having an ink jet head 61 with ink ejecting nozzles (not shown). The carriage 62 horizontally reciprocates along a carriage guide shaft 63 by means of the driving force of a carriage motor 65 (see FIG. 3 ).
[0072] The label printer 11 includes an ink supply mechanism 71 having a cartridge mounting section 14 to be mounted with ink cartridges 12 (see FIG. 2 ). The ink supply mechanism 71 has a vertical structure and is formed upright in the vertical direction on a base 72 of the publisher 1 . An end of a flexible ink supply tube 73 is connected to the ink supply mechanism 71 and the other end of the ink supply tube 73 is connected to the carriage 62 (see FIG. 4 ).
[0073] The ink of the ink cartridges 12 mounted on the ink supply mechanism 71 is supplied to the carriage 62 through the ink supply tube 73 , is supplied to the ink jet head 61 through a damper unit and a pressure distribution control unit (not shown) disposed in the carriage 62 , and then is ejected from the ink nozzles (not shown).
[0074] A pressurizing mechanism 74 is disposed in the ink supply mechanism 71 so as to put the main portion is above the ink supply mechanism. The pressurizing mechanism 74 pressurizes the ink cartridges 12 by blowing out compressed air, thereby sending out the ink stored in ink packs of the ink cartridges 12 .
[0075] A head maintenance mechanism 81 is disposed below the home position (position shown in FIG. 4 ) of the carriage 62 .
[0076] The head maintenance mechanism 81 includes a head cap 82 covering the ink nozzles of the ink jet head 61 exposed from the bottom surface of the carriage 62 located at the home position and a waste ink suction pump 83 sucking the ink discharged to the head cap 82 due to a head cleaning operation or an ink filling operation of the ink jet head 61 .
[0077] The ink sucked by the waste ink suction pump 83 of the head maintenance mechanism 81 is sent to a waste ink tank 85 through a tube 84 .
[0078] In the waste ink tank 85 , an absorbing material is disposed in a case 86 and the top surface is covered with a cover 88 having plural ventholes 87 .
[0079] A waste ink receiver 89 as a part of the waste ink tank 85 is disposed below the head maintenance mechanism 81 and receives the ink from the head maintenance mechanism 81 . Then, the ink is absorbed by the absorbing material.
[0080] As shown in FIG. 5 , in the medium transporting unit 31 , the horizontal supporting plate 34 and the top plate 33 of the cassis 32 is supported by the vertical guide shaft 35 disposed in the vertical direction. Here, the chassis 32 is pivotable. The transport arm 36 is supported by the chassis 32 so as to be lifted up and down.
[0081] As shown in FIG. 6 , the lift mechanism of the transport arm 36 includes a lifting driving motor (lift mechanism) 37 as a driving source, which employs a pulse motor in this embodiment. The rotation of the driving motor 37 is transmitted to a driving pulley 101 through a pinion 97 and a transmission gear 98 fitted to an output shaft of the driving motor 37 . The driving pulley 101 is supported to be rotatable about a horizontal rotation shaft in the vicinity of the top end of the chassis 32 . A driven pulley 103 is supported to be rotatable about the horizontal rotation shaft in the vicinity of the bottom end of the chassis 32 . A timing belt (lift mechanism) 104 is suspended on the driving pulley 101 and the driven pulley 103 . As shown in FIG. 7 , a base 110 of the transport arm 36 is connected to one horizontal end of the timing belt 104 through a belt clip (lift member) 112 .
[0082] Accordingly, when the driving motor 37 is activated, the timing belt 104 moves in the vertical direction and the transport arm 36 attached thereto is thus lifted up and down along the vertical guide shaft 35 . A sensor not shown for detecting the home position of the timing belt 104 is attached to the chassis 32 .
[0083] As shown in FIG. 5 , a rotation mechanism of the transport arm 36 includes a rotational driving motor 105 as a driving source and a pinion (not shown) is fitted to the output shaft of the driving motor 105 . The rotation of the pinion is transmitted to the fan-shaped final-stage gear 109 through a reduction gear train having a transmission gear 107 . The fan-shaped final-stage gear 109 can rotate horizontally about the vertical guide shaft 35 . The final-stage gear 109 is mounted to the chassis 32 having constituent elements of the lift mechanism for the transport arm 36 . When the driving motor 105 is activated, the fan-shaped final-stage gear 109 rotates horizontally and thus the chassis 32 mounted thereon monolithically rotates horizontally about the vertical guide shaft 35 . As a result, the transport arm 36 retained by the lift mechanism mounted on the chassis 32 rotates horizontally about the vertical guide shaft 35 . A sensor not shown for detecting the home position (a position just above the medium trays 41 a and 51 where the transport arm 36 is located at the medium transfer position) of the final-stage gear 109 and positions just above the blank medium stacker 21 and the completed medium stacker 22 is fitted to the base 72 .
[0084] Next, a supporting structure of the transport arm 36 will be described.
[0085] As shown in FIGS. 7 and 8 , a sliding shaft (support portion) 111 is vertically disposed on the base 110 of the transport arm 36 . The sliding shaft 111 is inserted through a shaft hole 112 a of the belt clip 112 fixed by holding the timing belt 104 (see FIG. 7 ) so as to be slidable from the upside. In FIG. 8 , the timing belt 104 is omitted.
[0086] A locking piece 112 b is formed in the belt clip 112 . An end of a first tension spring (first elastic urging means 113 ) which is a coil spring is connected to the locking piece 112 b . The other end of the first tension spring 113 is connected to a fixed piece 115 formed in the base 110 of the transport arm 36 and disposed above the locking piece 112 b . Accordingly, the base 110 of the transport arm 36 is urged downward by the first tension spring 113 .
[0087] A fixing portion 112 c for fixing the timing belt 104 therebetween is formed in the belt clip 112 .
[0088] A pressing lever 116 attached to the base 110 of the transport arm 36 is disposed below the belt clip 112 . The pressing lever 116 is laterally inserted through an insertion hole 118 formed in a supporting plate 117 disposed on the bottom of the base 110 of the transport arm 36 and is pivotable about a supporting point in the supporting plate 117 . An end of a second tension spring (second elastic urging means) 119 formed of a coil spring having an urging force greater than that of the first tension spring 113 is connected to an end of the pressing lever 116 and the other end of the second tension spring 119 is connected to a fixed piece 120 that is formed in the base and disposed above the end of the pressing lever 116 . Accordingly, the end of the pressing lever 116 is urged upward by the second tension spring 119 . A pivot regulating piece 121 formed on the base 110 is disposed above the vicinity of the end of the pressing lever 116 and the pivot of the pressing lever 116 urged upward by the second tension spring 119 is regulated to a predetermined position. The belt clip 112 is disposed at a position apart from the pressing lever 116 regulated by the pivot regulating piece 121 , by clearance S.
[0089] In the above-mentioned supporting structure, when the timing belt 104 is driven by the lifting driving motor 37 (see FIG. 5 ), the transport arm 36 is lifted up and down monolithically with the belt clip 112 fixed to the timing belt 104 . When a medium guide 133 to be described later or a holding mechanism 130 comes in contact with the medium and a down load of the transport arm 36 increases, only the belt clip 112 moves down against the urging force of the first tension spring 113 relative to the transport arm 36 . When the belt clip 112 further moves down by means of the timing belt 104 , the belt clip 112 comes in contact with the pressing lever 116 , the transport arm 36 is slightly bent, and then the pressing lever 116 pivots about a support point in the supporting plate 117 against the urging force of the second tension spring 119 .
[0090] Next, inner mechanisms of the transport arm 36 will be described.
[0091] As shown in FIG. 9 , the transport arm 36 includes a longitudinal arm base 125 a having a rectangular shape in the plan view and an arm case 125 b having the same profile as the arm base 125 a so as to cover the arm base. The arm base 125 a is provided with a holding mechanism 130 for holding a medium M, a separation mechanism 131 , and a medium detecting mechanism 200 . The holding mechanism 130 , the separation mechanism 131 , and the medium detecting mechanism 200 are covered with the arm case 125 b.
[0092] As shown in FIGS. 10 and 11 , a bottom portion in the vicinity of the end of the arm base 125 a serves as the holding portion 132 for holding a medium M. The medium guide 133 is disposed in the holding portion 132 .
[0093] As shown in FIGS. 12 and 13 , the center of the medium guide 133 corresponds to the pickup center of the medium M and the medium guide has a guide portion 135 protruding downward at the center of a fixed portion 134 fixed to the bottom surface of the arm base 125 a . The guide portion 135 has a cylindrical base end 135 a formed with a diameter slightly smaller than that of the center hole Ma of the medium M and a guide surface 135 b formed in a cone shape that points downward from the base end 135 a . The medium guide 133 is inserted into the center hole Ma of the medium M by approaching the medium M, the inner circumferential surface Mb of the center hole Ma of the medium m is guided by the guide surface 135 b , the center position of the medium M is aligned with the center position of the medium guide 133 by the guide surface 135 b , and then the center hole Ma of the medium M is guided by the base end 135 a , whereby the base end 135 a is inserted through the center hole of the medium M.
[0094] Three window portions 133 a are formed in the medium guide 133 . Three holding claws 141 to 143 of the holding mechanism 130 and an operation piece 183 of the pressing lever 182 of the separation mechanism 131 can protrude and retreat into and from the window portions 133 a.
[0095] As shown in FIGS. 12 and 13 , the holding mechanism 130 has three cylindrical holding claws 141 to 143 which are disposed at an approximate equiangular interval (120°) on the same circle. The holding claws 141 to 143 protrudes vertically downward from circular hole 125 c formed in the arm base 125 a and are disposed inside the window portions 133 a of the medium guide 133 . The three holding claws 141 to 143 are inserted into the center hole Ma of the medium, guided to the base end 135 a of the medium guide 133 , then are made to move outward, and are made to protrude from the window portions 133 a of the medium guide 133 , thereby pressing the inner circumferential surface Mb of the center hole Ma of the medium M to hold the medium M.
[0096] As shown in FIG. 20 , the holding claws 141 to 143 are attached to lower ends of supporting pins 151 to 153 having a diameter greater than the holding claws. The supporting pins 151 to 153 extend upwardly through the circular hole 125 c of the arm base 125 a and three pivoting plates 161 to 163 disposed on the top surface of the arm base 125 a . Pivoting center axes 171 to 173 are vertically fixed to the arm base 125 a at the equiangular interval on the same circle so as to surround the circular hole 125 c . The pivoting plates 161 to 163 are supported to be pivotable about the pivoting center axes 171 to 173 , respectively.
[0097] As shown in FIGS. 14 to 16 , each pivoting plate 161 to 163 includes a front arm portion 161 a to 163 a extending counterclockwise in the top view, a rear arm portion 161 b to 163 b extending clockwise in the top view, and supporting arms 161 c to 163 c protruding inside the center hole 125 c from the pivoting center, along the arm base 125 a from the pivoting center axis 171 to 173 . The supporting pins 151 to 153 are vertically formed on the rear surface of the ends of the supporting arms 161 c to 163 c , respectively.
[0098] A longitudinal hole 161 d in a direction substantially perpendicular to the circular hole 125 c is formed in the rear arm portion 161 b of the pivoting plate 161 . A slide pin 163 f protruding downward from the rear end of the front arm portion 163 a of the pivoting plate 163 is slidably inserted through the longitudinal hole 161 d.
[0099] A slide surface 163 e (see FIG. 16 ) in a direction substantially perpendicular to the circular hole 125 c is formed at the end of the rear arm portion 163 b of the pivoting plate 163 and the front end of the front arm portion 162 a of the pivoting plate 162 is established so as not to come in contact with the slide surface 163 e . A slide surface 162 e in the direction substantially perpendicular to the circular hole 125 c is formed at the end of the rear arm portion 162 b of the pivoting plate 162 and the front end of the front arm portion 161 a of the pivoting plate 161 is in sliding contact with the slide surface 162 e . Here, the longitudinal hole 161 d of the pivoting plate 161 and the slide surfaces 162 e and 163 e of the pivoting plates 162 and 163 are formed in a concave curved shape set to allow the pivoting plates 161 to 163 to pivot the in same direction.
[0100] Tension coil springs (urging members) 174 are suspended between the rear arm portion 161 b of the pivoting plate 161 and the rear arm portion 162 b of the pivoting plate 162 , between the rear arm portion 162 b of the pivoting plate 162 and the rear arm portion 163 b of the pivoting plate 163 , and between the rear arm portion 163 b of the pivoting plate 163 and the rear arm portion 161 b of the pivoting plate 161 . By means of the tension of the tension coil springs 174 , the pivoting plates 161 to 163 are supported without pivoting independently and the urging force, in the direction indicated by arrow R 1 in FIG. 16 , that is, in the direction in which the holding claws 141 to 143 move outward, is applied to the pivoting plates 161 to 163 .
[0101] In the state shown in FIG. 16 , the circumscribed circle of the holding claws 141 to 143 attached to the ends of the supporting arms 161 c to 163 c of the pivoting arms 161 to 163 has a diameter greater than the inner diameter of the center hole Ma of the medium M. In this state, when pivoting plate 161 is made to pivot in the direction indicated by arrow R 2 , the other pivoting plates 162 and 163 accordingly pivot in the same direction as indicated by arrow R 2 . As a result, the supporting arms 161 c to 163 c of the pivoting plates 161 to 163 move to the center of the circular hole 125 c and the holding claws 141 to 143 attached to the ends move inward so that they can be inserted into the center hole Ma of the medium M.
[0102] In this state, when the holding claws 141 to 143 are inserted into the center hole Ma of the Medium and then the pivoting plates 161 to 163 are made to pivot in the opposite direction R 1 , the holding claws 141 to 143 move outward in the radius direction. As a result, the holding claws 141 to 143 are pressed on the inner circumferential surface Mb of the center hole of the medium M, thereby holding the medium M.
[0103] As shown in FIG. 14 , an operation arm 161 g extending to the opposite side of the supporting arm 161 c is formed in the pivoting plate 161 . The end of one arm portion 175 a of a link 175 is rotatably connected to the end of the operation arm 161 g . The link 175 is supported by the arm base 125 a so as to be rotatable about a middle portion thereof and the end of the opposite arm portion 175 b is connected to an operation rod 176 a of an electromagnetic solenoid 176 . When the electromagnetic solenoid 176 is turned off, the operation rod 176 a protrudes by action of the spring force of a built-in spring.
[0104] In this state, where the electromagnetic solenoid 176 is turned on, the operation rod 176 a is reversely inserted against the spring force in the electromagnetic solenoid, the link 175 pivots clockwise, and the pivoting plate 161 thus pivots in the direction of R 2 . Then, as shown in FIG. 17 , the slide surface 162 e of the rear arm portion 162 b of the pivoting plate 162 comes in sliding contact with the end of the front arm portion 161 a of the pivoting plate 161 and the inner surface of the longitudinal hole 161 d of the rear arm portion 161 b of the pivoting plate 161 comes in sliding contact with the slide pin 163 f of the front arm portion 163 a of the pivoting plate 163 . Accordingly, the slide surface 162 e of the pivoting plate 162 comes in sliding contact with the end of the front arm portion 161 a of the pivoting plate 161 and slides outward in the diameter direction of the circular hole 125 c , whereby the pivoting plate 162 pivots in the direction of R 2 . The inner surface of the longitudinal hole 161 d of the rear arm portion 161 b of the pivoting plate 161 comes in sliding contact with the slide pin 163 f of the front arm portion 163 a of the pivoting plate 163 and thus the front arm portion 163 a of the pivoting plate 163 slides toward the center of the circular hole 125 c , whereby the pivoting plate 163 also pivots in the direction of R 2 .
[0105] In this way, when the pivoting plate 161 pivots in the direction of R 2 , the pivoting force in the direction of R 2 of the pivoting plate 161 is transmitted to the other pivoting plates 162 and 163 and thus the pivoting plates 162 and 163 also pivot in the direction of R 2 , as shown in FIG. 18 . The holding claws 141 to 143 disposed in the supporting arms 161 c to 163 c of the pivoting plates 161 to 163 are disposed in the circumscribed circle sufficiently smaller than the center hole Ma of the medium M and move inward until it can be inserted into the center hole Ma of the medium M.
[0106] In this state, when the electromagnetic solenoid 176 is turned off, the operation rod 176 a is made to protrude by means of the spring force of the spring in the electromagnetic solenoid and the tension coil spring 174 and the link 175 thus pivots. Then, the pivoting motion of the link 175 is transmitted to the pivoting plate 161 and thus the pivoting plate 161 pivots in the direction of R 1 . Accordingly, in the other pivoting plates 162 and 163 , the rear arm portions 162 b and 163 b move toward the center of the circular hole 125 c by means of the tension of the tension coil spring 174 and thus the pivoting plates 162 and 163 also pivot in the direction of R 1 like the pivoting plate 161 . As a result, as shown in FIG. 19 , the holding claws 141 to 143 move outward and the holding claws 141 to 143 are pressed on the inner circumferential surface Mb of the center hole Ma of the medium M, thereby holding the medium M.
[0107] At this time, since the pivoting plates 162 and 163 pivot in the direction of R 1 by means of the tension of the tension coil spring 174 independently of the pivoting plate 161 , the holding claws 141 to 143 move outward in the radius direction independently of each other and thus are pressed on the inner circumferential surface Mb of the center hole Ma of the medium M.
[0108] As shown in FIG. 20 , each of three holding claws 141 to 143 includes a cylindrical pin 141 a to 143 a protruding form the bottom end of the supporting pin 151 to 153 and an elastic cylinder 141 b to 143 b made of rubber to surround the pin 141 a to 143 a concentrically. Here, although the cylindrical pin 142 a and the elastic cylinder 142 b are not shown in FIG. 20 , these components are provided with the holding claw 142 in a similar configuration as the holding claws 141 and 143 . In the holding claws 141 to 143 , the downward protruding length l is equal to or smaller than the thickness t 1 of the medium M to be held. It is preferable that the producing length l is equal to or greater than the thickness t 2 of the inner circumferential surface Mb of the center hole Ma of the medium M and equal to or smaller than the thickness t 1 of the medium M including the height of a ring-shaped protrusion Mc. Accordingly, when the mediums M stacked in the thickness direction are held, the holding claws 141 to 143 hold only the uppermost medium M without coming in contact with the inner circumferential surface Mb of the second medium M. The portions of the supporting pins 151 to 153 close to the holding claws 141 to 143 are contact surfaces 151 a to 151 b with the medium Mm to be held.
[0109] As shown in FIGS. 21 to 23 , the separation mechanism 131 disposed in the arm base 125 a of the transport arm 36 includes a pressing lever 182 that is rotatably supported by a support shaft 181 formed in the arm base 125 a . The pressing lever 182 includes two components of a front lever portion 182 a on the holding side and a rear lever portion 182 b on the rotation side. In the front lever portion 182 a , a cylindrical bearing portion 184 inserted through the support shaft 181 formed in the arm base 125 a is made to protrude upward and the rear lever portion 182 b is pivotably supported by the bearing portion 184 . The front lever portion 182 a and the rear lever portion 182 b are pivotable in a predetermined range by a locking portion 185 which is prevented from being separated from the front lever portion 182 a and an opening 186 having a width greater than the width of the locking portion 185 and being disposed in the rear lever portion 182 b . As shown in FIGS. 23 and 26 , the front lever portion 182 a and the rear lever portion 182 b are urged in a direction by a buffer spring 187 which is a twist coil spring. Specifically speaking, in the buffer spring 187 attached to the outer circumference of the pivoting portion of the rear lever portion 182 b , one arm portion 187 a urges a receiving portion 182 d of the front lever portion 182 a and the other arm portion 187 b urges a receiving portion 182 e of the rear lever portion 182 b so as to be apart from each other. Accordingly, in the pressing lever 182 , a great load is applied to an operation piece 183 to be described later when the rear lever portion 182 b allows the front lever portion 182 a to pivot, and the buffer spring 187 is bent when the front lever portion 182 a cannot pivot, thereby preventing the damage of the operation piece 183 . The front lever portion 182 a has the operation piece 183 bent from the front end to the down side and laterally bent in an L shape. The operation piece 183 is disposed in the medium guide 133 of the holding portion 132 .
[0110] In a state where the holding claws 141 to 143 of the holding portion 132 hold the medium M, the operation piece 183 of the pressing lever 182 is disposed horizontal below the medium M. Specifically, the operation piece is disposed at a position corresponding to the second medium M of the mediums stacked in the thickness direction.
[0111] When the pressing lever 182 pivots at the connection point 181 in the direction of R 3 in FIG. 21 , the operation piece 183 protrudes laterally from the window portion 133 a of the medium guide 133 and comes in pressing contact with the inner circumferential surface Mb of the center hole Ma of the second medium M just below the uppermost medium M held by the holding claws 141 to 143 . When the pressing lever 182 pivots in the opposite direction of R 4 in this state, the operation piece 183 is inserted into the medium guide 133 .
[0112] A pivot mechanism 190 for allowing the pressing lever 182 to pivot is disposed in the rear lever portion 182 b of the pressing lever 182 . The pivot mechanism 190 includes a complex clutch gear 191 , a vertical complex transmission gear 192 , a horizontal complex transmission gear 193 , and a lock 194 .
[0113] As shown in FIG. 5 , the lock 194 is vertically supported by the chassis 32 constituting the medium transporting unit 31 so as to be parallel to the vertical guide shaft 35 . The lock 194 engages with a pinion 193 b of the horizontal complex transmission gear 193 supported by the arm base 125 a so as to be rotatable about a horizontal shaft 193 a (see FIG. 23 ). By lifting up and down the transport arm 36 , the horizontal complex transmission gear 193 , which has the pinion 193 b that engages with the lock 194 , rotates.
[0114] A screw gear 193 c is disposed in the horizontal complex transmission gear 193 . The screw gear 193 c engages with a screw gear 192 b of the vertical complex transmission gear 192 supported by the arm base 125 a so as to be rotatable about a vertical shaft 192 a . Accordingly, when the horizontal complex transmission gear 193 rotates, the rotation of the horizontal complex transmission gear 193 having the horizontal shaft 193 a is transmitted to the vertical complex transmission gear 192 having the vertical shaft 192 a through the screw gears 192 b and 193 c engaging with each other, thereby allowing the vertical complex transmission gear 192 to rotate.
[0115] The vertical complex transmission gear 192 includes a horizontal gear 192 c . The horizontal gear 192 c engages with a horizontal gear 191 b of the complex clutch gear 191 supported by the arm base 125 a so as to be rotatable about the vertical shaft 191 a . Accordingly, when the vertical complex transmission gear 192 rotates, the rotating force of the vertical complex transmission gear 192 is transmitted to the complex clutch gear 191 through the horizontal gears 191 b and 192 c engaging with each other, thereby allowing the complex clutch gear 191 to rotate.
[0116] As shown in FIGS. 24 and 25 , the complex clutch gear 191 includes an intermittent gear 191 c that is rotatable relative to the horizontal gear 191 b . A clutch mechanism 195 is disposed between the horizontal gear 191 b and the intermittent gear 191 c . The horizontal gear 191 b has a cylinder shaft 191 d through which the shaft 191 a is inserted. The cylinder shaft 191 d is inserted through a cylinder shaft 191 e formed in the intermittent gear 191 c.
[0117] As shown in FIG. 25 , the intermittent gear 191 c has a gear train 196 including plural gears 196 a on a part of the circumferential surface. The gear train 196 can engage with the horizontal gear 192 c of the vertical complex transmission gear 192 .
[0118] The clutch mechanism 195 disposed in the complex clutch gear 191 has a twist coil spring 197 wound on the cylinder shaft 191 e of the intermittent gear 191 c . When the horizontal gear 191 b is made to rotate in the counterclockwise direction of R 5 as viewed from the upside in FIG. 25 by the horizontal gear 192 c of the vertical complex transmission gear 192 , the intermittent gear 191 c is made to rotate with the horizontal gear 191 b by the frictional force generated from the twist coil spring 197 . Accordingly, the gear train 196 engages with the horizontal gear 192 c of the vertical complex transmission gear 192 and thus the intermittent gear 191 c rotates in the direction of R 5 along with the horizontal gear 191 b . On the contrary, when the horizontal gear 191 b is made to rotate in the clockwise direction of R 6 as viewed from the upside in FIG. 25 by the horizontal gear 192 c of the vertical complex transmission gear 192 , the intermittent gear 191 c is made to rotate along with the horizontal gear 191 b by means of the frictional force generated from the twist coil spring 197 . Accordingly, the gear train 196 engages with the horizontal gear 192 c of the vertical complex transmission gear 192 and thus the intermittent gear 191 c rotates in the direction of R 6 along with the horizontal gear 191 b.
[0119] A cam hole 198 is formed in the intermittent gear 191 c . A cam pin 182 c protruding downward from the vicinity of the rear end of the rear lever portion 182 b of the pressing lever 182 is slidably disposed in the cam hole 198 . The cam hole 198 has a path changing from the center to the outer circumference in the clockwise direction in the top view. Accordingly, when the intermittent gear 191 c rotates in the counterclockwise direction of R 5 in the top view in the state shown in FIG. 26 , the cam pin 182 c in the cam hole 198 is displaced to the outer circumference. Accordingly, as shown in FIG. 27 , the pressing lever 182 pivots in the direction of R 3 about a connection point 181 and thus the operation piece 183 protrudes to the outside of the medium guide 133 . In this state, when the intermittent gear 191 c rotates in the clockwise direction of R 6 in the top view, the cam pin 182 c in the cam hole 198 is displaced to the inner circumference. Accordingly, as shown in FIG. 26 , the pressing lever 182 pivots about the connection point 181 in the direction of R 4 and thus the operation piece 183 is inserted into the medium guide 133 .
[0120] In the separation mechanism 131 having the above-mentioned configuration, when the transport arm 36 starts going up, the complex clutch gear 191 starts rotating in the direction of R 5 . When the transport arm 36 further goes up and the complex clutch gear 191 rotates by a predetermined angle (about 45 degrees) from the state shown in FIG. 26 to the state shown in FIG. 27 , the pressing lever 182 pivots in the direction of R 3 (see FIG. 21 ) and thus the operation piece 183 of the pressing lever 182 separates the second medium M in the meantime. When the transport arm 36 goes down, the complex clutch gear 191 rotates in the direction of R 6 . Accordingly, the pressing lever 182 rotates in the direction of R 4 (see FIG. 21 ) and the operation piece 183 is inserted into the medium guide 133 as shown in FIG. 26 . Even when the transport arm 36 goes down in this state, the gear train 196 runs off from the horizontal gear 192 c after the intermittent gear 191 c of the complex clutch gear 191 rotates by a predetermined angle (about 45 degrees) in the direction of R 6 (see FIG. 26 ) by the horizontal gear 192 c of the vertical complex transmission gear 192 and thus the intermittent gear idly rotates relative to the horizontal gear 191 b.
[0121] As shown in FIG. 9 , the medium detecting mechanism 200 includes a detection lever 201 of which the rear end is pivotably supported and the front end is bent downward to protrude toward the bottom surface of the arm base 125 a and a detector 202 disposed aside the detection lever 201 . In the medium detecting mechanism 200 , when the transport arm 36 goes down to bring the top surface of the medium M into contact with the detection lever 201 and thus the detection lever 201 pivots upward to allow the detection lever 201 to depart from the detection area of the detector 202 , the detector 202 is turned on and thus it is possible to detect an approaching state to the medium M from the detection signal output from the detector 202 .
[0122] Next, an operation of picking up a medium M in the medium transporting unit 31 having the above-mentioned configuration will be described.
[0123] An example where the uppermost medium M of the mediums M stacked is held and picked up from the blank medium stacker 21 will be described with reference to the flowchart of controlling the lifting driving motor of the transport arm, which is shown in FIG. 29 .
[0124] First, in a state where the transport arm 36 is located at a predetermined height position just above the blank medium stacker 21 , the electromagnetic solenoid 176 of the holding mechanism 130 is turned on. In this state, the operation rod 176 a of the electromagnetic solenoid 176 is inserted against the built-in spring, this movement is transmitted to the pivoting plate 161 through the link 175 , and the pivoting plate 161 pivots in the direction of R 2 in FIG. 16 . Accordingly, the other pivoting plates 162 and 163 pivot in the same direction and the holding claws 141 to 143 attached to the ends of the supporting arms 161 c to 163 c of three pivoting plates 161 to 163 moves close to each other, whereby it gets pointed so as to be inserted into the center hole Ma of the medium M.
[0125] Thereafter, the lifting driving motor 37 of the transport arm 36 is driven (ST 1 ) and the belt clip 112 fixed to the timing belt 104 goes down (ST 2 ), thereby starting the lift-down operation of the transport arm 36 . When the transport arm 36 is lifted down and gets close to the uppermost medium M, the medium guide 133 of the holding portion 132 is inserted into the center hole Ma of the medium M. Here, even when the center of the medium M in the blank medium stacker 21 runs off from the center of the holding portion 132 , the inner circumferential surface Mb of the center hole Ma of the medium M comes in contact with the conical guide surface 135 b , the center position of the medium M is thus aligned with the center position of the medium guide 133 by the guide surface 135 b , the center hole Ma of the medium M is guided to the base end 135 a , and thus the base end 135 a is inserted through the center hole Ma of the medium M. That is, the center of the medium M to be held is positioned at the center of the holding portion 132 which is the pickup center.
[0126] At this time, when the end of the detection lever 201 of the medium detecting mechanism 200 mounted on the transport arm 36 comes in contact with the surface of the medium M, the detection lever 201 pivots upward with the lift-down of the transport arm 36 and the detection lever 201 runs off from the detection area of the detector 202 , thereby turning on the detector 202 (ST 3 ) to detect the access state to the medium M. It is determined whether the destination of the transport arm 36 is the blank medium stacker 21 receiving plural mediums stacked therein or the medium tray 51 or the medium tray 41 a receiving a single medium (ST 4 ). When the destination is the medium trays 41 a and 51 of the drive and the printer, the driving motor is driven separately (ST 5 ) by adding pulse T 2 to pulse T 1 applied to the driving motor 37 , the driving motor is stopped (ST 7 ) by lifting down the transport arm 36 by a predetermined distance, and the holding claws 141 to 143 of the holding mechanism 130 mounted on the transport arm 36 are inserted into the center hole Ma of the medium M.
[0127] The mediums M are stacked in the blank medium stacker 21 . Since the stacked mediums M are in close contact with each other, an adhesive force may occur between the mediums M.
[0128] Accordingly, when the second medium M is adhered to the uppermost medium M, it is difficult to horizontally position the uppermost medium only by bringing the holding claws 141 to 143 into contact with the inner circumferential surface Mb of the center hole Ma of the medium.
[0129] Accordingly, in the medium transporting unit 31 , by applying a predetermined pressing force to the uppermost medium M from the top, the pressing force toward the lateral end of the medium M is applied by the guide surface 135 b of the medium guide 133 , thereby satisfactorily moving and positioning the medium M laterally.
[0130] A relation between a position of the belt clip 112 of the transport arm 36 and a load on the medium M will be described.
[0131] FIG. 28 is a graph illustrating a relation between a down stroke of the belt clip of the transport arm and a load on the medium.
[0132] First, in a state where the holding portion of the transport arm 36 is in contact with the uppermost medium M (a state between A and B in FIG. 28 ), when the driving motor 37 continues driving by further applying pulse T 2 (ST 5 ), the belt clip 112 fixed to the timing belt 104 is lifted down against the urging force of the first tension spring 113 having a small spring force, the belt clip 112 goes down by a distance corresponding to the clearance S, and then the belt clip 112 comes in contact with the pressing lever 116 (state B in FIG. 28 ). Accordingly, until the belt clip 112 comes in contact with the pressing lever 116 after the holding portion 132 comes in contact with the uppermost medium, the first elastic pressing force including the urging force of the first tension spring 113 having the small spring force is applied to the uppermost medium M (state between A and B in FIG. 28 ).
[0133] When the driving motor 37 is further driven, the belt clip 112 further goes down. At this time, since the belt clip 112 is in contact with the pressing lever 116 , the lift-down force of the belt clip 112 is transmitted to the transport arm 36 to bend the transporting arm 36 and the bending force is applied as a pressing force to the uppermost medium M (state between B and C in FIG. 28 ).
[0134] When the driving motor 37 is further driven (ST 5 ), the belt clip 112 goes down and stops (ST 7 and ST 8 ), and thus the bending force of the transport arm 36 is greater than the urging force of the second tension spring 119 having a great spring force (state C in FIG. 28 ), the pressing lever 116 pivots about a supporting point on the supporting plate 117 against the urging force of the second tension spring 119 . Accordingly, the second elastic pressing force obtained by adding the urging force of the second tension spring 119 to the urging force of the first tension spring 113 and the bending force of the transport arm 36 is applied to the uppermost medium M (states between C and E in FIG. 28 ).
[0135] In the medium transporting unit 31 having the above-mentioned load characteristic, the driving motor 37 is stopped at a proper position (for example, position of D in FIG. 28 ) in the state where the pressing force obtained by adding the urging force of the second tension spring 119 to the urging force of the first tension spring 113 and the bending force of the transport arm 36 is applied to the medium M (state between C and E in FIG. 28 ).
[0136] As a result, among the stacked mediums M in the blank medium stacker 21 , a proper load (about 10 N) can be applied to the uppermost medium M. Accordingly, regardless of the adhesion to the second medium M, it is possible to satisfactorily move laterally and position the medium M by the use of the guide surface 135 b of the medium guide 133 .
[0137] Even when the center position of the medium M runs off, it is possible to satisfactorily insert the medium guide 133 into the center hole Ma of the medium and to position the medium, by applying a load.
[0138] When the rigidity of the transport arm 36 is enhanced and the spring constant of the second tension spring 119 is increased, it is possible to obtain a necessary load by reducing the stroke of the belt clip 112 for generating the bending force of the transport arm 36 (state between B and C in FIG. 28 ).
[0139] When the medium M is lifted up from the medium trays 41 a and 51 of the medium drive 41 and the label printer 11 including only a single medium M, ST 6 is performed as the determination result whether the destination of the transport arm 36 is the blank medium stacker 21 or the medium tray 51 of the medium tray 41 a receiving a single medium (ST 4 ) and only pulse T 1 is thus applied to the driving motor 37 (ST 6 ).
[0140] In this case, the driving motor is stopped in the region (clearance S in FIG. 7 ) where the belt clip 112 fixed to the timing belt 104 is lifted down against the urging force of the first tension spring 113 having a small spring force. The medium M can be held by the use of the holding mechanism 130 in the state (state between A and B in FIG. 28 ) where the first elastic pressing force including the urging force of the first tension spring 113 having a small spring force is applied until the belt clip 112 comes in contact with the pressing lever 116 after the holding portion of the transport arm 36 comes in contact with the medium M. As a result, since the load applied on the medium trays 41 a and 51 at the time of tacking out the medium M can be reduced as much as possible, it is possible to suppress the overload due to the load on the medium trays 41 a and 51 .
[0141] In this way, in a state where the second elastic pressing force is applied to the uppermost medium M in the blank medium stacker 21 , the holding claws 141 to 143 inserted into the center hole Ma of the medium M are made to move outward and are pressed on the inner circumferential surface Mb of the center hole Ma.
[0142] Specifically, first, when the electromagnetic solenoid 176 is turned off and the operation rod 176 a thereof is made to protrude by action of the spring force, the pivoting plate 161 connected to the operation rod 176 a through the link 175 pivots in the direction of R 1 . Accordingly, the other pivoting plates 162 and 163 pivot in the direction of R 1 by means of the tension of the tension coil spring 174 , similarly to the pivoting plate 161 . As a result, the holding claws 141 to 143 move outward and the holding claws 141 to 143 are pressed on the inner circumferential surface Mb of the center hole of the medium M, thereby holding the medium M.
[0143] At this time, since the pivoting plates 162 and 163 pivot in the direction of R 1 by means of the tension of the tension coil spring 174 independently of the pivoting plate 161 , the holding claws 141 to 143 also move outward in the radius direction independently of each other and are pressed on the inner circumferential surface Mb of the center hole Ma of the medium M.
[0144] Therefore, even when the center position of the uppermost medium M runs off from the pickup center, the holding claws 141 to 143 move outward independently and thus all the holding claws 141 to 143 come in contact with the inner circumferential surface Mb of the center hole Ma of the medium M, thereby satisfactorily preventing holding failure and the like.
[0145] In addition, the downward protruding length of the holding claws 141 to 143 is equal to or less than the thickness of the medium to be held. Accordingly, even when the center position of the second medium M runs off from that of the uppermost medium M, it is possible to prevent such a problem that the holding claws 141 to 143 come in contact with the edge of the center hole Ma of the second medium M to cause the holding failure.
[0146] When the medium M is held in this way, the held medium M is lifted up by lifting up the transport arm 36 in the state where the holding claws 141 to 143 move outward in the diameter direction. At this time, since the held uppermost medium M is satisfactorily held by all the holding claws 141 to 143 , it is possible to smoothly pick up the medium without any holding failure.
[0147] When the transport arm 36 moves up to pick up the medium M, the pressing lever 182 of the separation mechanism 131 pivots in the direction of arrow R 3 in FIG. 21 about the connection point 181 and thus the operation piece 183 protrudes to the outside of the medium guide 133 .
[0148] Therefore, even if the second medium M is lifted up by adhesion to the lifted uppermost medium M, the operation piece 183 of the pressing lever 182 comes in contact with the inner circumferential surface Mb of the center hole Ma of the second medium M to satisfactorily separate the second medium, thereby lifting up only the uppermost medium M.
[0149] As described above, the medium transporting unit 31 according to the above-mentioned embodiment includes the separation mechanism 131 that separates the medium M just below the uppermost medium M to be held and lifted up by the holding mechanism 130 . Accordingly, even when the (second) medium M just below the medium M to be held is adhered thereto, it is possible to pick up and transport only the uppermost medium M without any holding failure by separating the just-below medium M.
[0150] The movable kick lever 182 having the operation piece 183 protruding outward in the diameter direction from the center hole Ma of the medium M and retreating is provided. Accordingly, by pivoting the kick lever 182 to allow the operation piece 183 to protrude at the time of holding and lifting up the uppermost medium M, it is possible to easily separate the just-below medium M adhered to the medium M to be held.
[0151] In addition, since the pivot mechanism 190 that pivots the kick lever 182 by lifting up and down the transport arm 36 is provided, it is possible to separate the medium M just below the medium M to be held by moving the kick lever 182 , without providing a specific driving mechanism.
[0152] Since the pivot mechanism 190 includes the lock 194 disposed in the vertical direction and the pinion 193 b engaging with the lock 194 and the kick lever 182 is made to pivot by means of the rotational force of the pinion 193 b rotating with the lift-up and lift-down motion of the transport arm 36 , it is possible to allow the operation piece 183 to protrude and retreat in the diameter direction by lifting up and down the transport arm 36 to easily move the kick lever 182 .
[0153] The pivot mechanism 190 includes the complex clutch gear 191 that can rotate by a predetermined angle at the time of lifting up the transport arm 36 . Accordingly, at the time of picking up the held medium M by lifting up the transport arm 36 , the kick lever 182 is made to move by a predetermined distance by the complex clutch gear 191 having rotated by a predetermined angle at the time of lifting up the transport arm 36 and it is thus possible to separate the medium M just below the holding object by allowing the operation piece 183 to protrude externally in the diameter direction by a predetermined distance.
[0154] At the time of lifting down the transport arm 36 so as to hold the medium M or to place the held medium M at a predetermined position, the kick lever 182 is made to pivot in the opposite direction by a predetermined distance by the complex clutch gear 191 having reversely rotated by a predetermined angle at the time of lifting down the transport arm 36 , and it is thus possible to insert the operation piece 183 , thereby preventing the operation piece 183 from interfering with the medium M to be held or the medium M to be placed.
[0155] It is preferable that the operation piece 183 is urged by the buffer spring 187 in a direction in which it protrudes, so that the operation piece does not move even when the kick lever 182 is made to pivot by a predetermined distance by the complex clutch gear 191 . This is, the operation piece is prevented from damage even when the medium to be held and the just-below medium are very strongly adhered to each other and they cannot be thus separated from each other or the operation piece 183 cannot move due to particles. It is preferable that the kick lever 182 includes two elements of the front lever portion 182 a having the operation piece 183 and the rear lever portion 182 b made to move by the complex clutch gear 191 . Such a configuration is effective for making the very small operation piece movable.
[0156] Since the publisher 1 includes the medium transporting unit 31 that can satisfactorily hold only the uppermost medium M stacked in the medium stackers 21 and 22 , it is possible to satisfactorily transport only a medium M to be held, thereby enhancing the processing reliability of the medium processing apparatus.
[0157] The invention is not limited to the above-mentioned embodiment but can be modified in various forms.
[0158] Although it has been described above that the kick lever 182 includes the lock 194 disposed in the vertical direction and the pinion 193 b engaging with the lock 194 and the kick lever 182 is made to pivot by means of the rotational force of the pinion 193 b rotating with the lift-up and lift-down motion of the transport arm 36 , the kick lever 182 may be driven by the publisher. Alternatively, although the kick lever 182 has included two elements, the kick lever 182 may have only one element, the operation piece portion may be provided as a particular element, and the operation piece 183 may be urged to the kick lever 182 in the protruding direction.
[0159] Although it has been described that the kick lever 182 is made to pivot by the complex clutch gear 191 , the kick lever 182 may be supported to be linearly movable by the arm base 125 a and may be made to linearly move by the clutch gear 191 .
|
A holding mechanism is operable to hold a top medium from a plurality of plate-shaped media accommodated in a stacker in a stacked manner. A transport arm supports the holding mechanism. The transport arm is provided with a separation mechanism operable to separate a second medium positioned just below the top medium which is held by the holding mechanism.
| 6
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 09/724,514, filed Nov. 27, 2000, and claims priority therefrom under 35 U.S.C. § 120. The priority application is currently pending.
FIELD OF THE INVENTION
[0002] Micromechanical and microoptomechanical structures fabricated on silicon-on-insulator (SOI) wafers are described. More particularly micromechanical and mircooptomechanical components created by chemically and mechanically modifying SOI wafers and metalizing a backside of the components are described.
BACKGROUND
[0003] Inherent thin film properties of materials limit many surface micromachining processes. For example, variability of materials properties in polysilicon thin films (such as Young's modulus and Poisson's ratio, residual stress, and stress gradients) can prohibit manufacture of desired microstructures. This is particularly apparent in microoptical components such as mirrors, lenses, and diffraction gratings, which must be very flat for high-optical performance, and normally have to be made in the single crystal silicon layer. Since conventional surface micromachining requires that all components be made in polysilicon layers, optical performance can be limited.
[0004] The leading commercial microelectromechanical (MEMS) processing technologies are (1) bulk micromachining of single crystal silicon, and (2) surface micromachining of polycrystalline silicon. Each of these processing technologies has associated benefits and barriers. Bulk micromachining of single crystal silicon, an excellent material with well-controlled electrical and mechanical properties in its pure state, has historically utilized wet anisotropic wet etching to form mechanical elements. In this process, the etch rate is dependent on the crystallographic planes that are exposed to the etch solution, so that mechanical elements are formed that are aligned to the rate limiting crystallographic planes. For silicon these planes are the (1,1,1) crystal planes. The alignment of mechanical features to the crystallographic planes leads to limitations in the geometries that can be generated using this technique. Typical geometries include v-groove trenches and inverted pyramidal structures in (1,0,0) oriented silicon wafers, where the trenches and inverted pyramids are bound by (1,1,1) crystallographic planes. Geometries that include convex comers are not allowed unless additional measures are taken to protect etching of the crystal planes that make up the comers. The etch rate also varies with dopant concentration, so that the etch rate can be modified by the incorporation of dopant atoms, which substitute for silicon atoms in the crystal lattice. A boron dopant concentration on the order of 5×10 19 /cm 3 is sufficient to completely stop etching, so that mechanical elements bounded by other crystal planes can be generated by using dopant “etch stop” techniques. However, dopant concentrations of this magnitude are sufficient to modify the desirable electrical and mechanical properties of the pure single crystal silicon material, leading to device design and manufacturability constraints. Recent advances in Deep Reactive Ion Etching (DRIE) (see, e.g., J. K. Bhardwaj and H. Ashraf, “Advanced silicon etching using high density plasmas”, Micromachining and Microfabrication Process Technology, Oct. 23-24, 1995, Austin, Tex., SPIE Proceedings Vol. 2639, pg. 224) which utilize sidewall passivation and ion beam directionality to achieve etch anisotropy, have relaxed the in-plane geometric design constraints, but still require etch stop techniques to control the depth of the etch into the wafer, and additional processing steps are required to undercut a structure to release it from the substrate.
[0005] In contrast to bulk micromachining, surface micromachining of polycrystalline silicon utilizes chemical vapor deposition (CVD) and reactive ion etching (RIE) patterning techniques to form mechanical elements from stacked layers of thin films (see, e.g., R. T. Howe, “Surface micromachining for microsensors and microactuators”, J. Vac. Sci. Technol. B6, (1988) 1809). Typically CVD polysilicon is used to form the mechanical elements, CVD nitride is used to form electrical insulators, and CVD oxide is used as a sacrificial layer. Removal of the oxide by wet or dry etching releases the polysilicon thin film structures. The advantage of the surface micromachining process is the ability to make complex structures in the direction normal to the wafer surface by stacking releasable polysilicon layers (see, e.g., K. S. J. Pister, M. W. Judy, S. R. Burgett, and R. S. Fearing, “Microfabricated hinges”, Sensors and Actuators A33, (1992) 249 and L. Y. Lin, S. S. Lee, K. S. J. Pister, and M. C. Wu, “Micromachined three-dimensional micro-optics for free-space optical system”, IEEE Photon. Technol. Lett. 6, (1994) 1445) and complete geometric design freedom in the plane of the wafer since the device layers are patterned using isotropic RIE etching techniques. An additional advantage of surface micromachining is that it utilizes thin film materials such as polysilicon, oxide, nitride, and aluminum, that are commonly used in microelectronic device fabrication, albeit with different materials properties that are optimized for mechanical rather than electrical performance. This commonality in materials allows for increased integration of microelectronic and micromechanical components into the same fabrication process, as demonstrated in Analog Devices' integrated accelerometer, and in SSI Technologies' integrated pressure sensor.
[0006] While surface micromachining relaxes many of the limitations inherent in bulk micromachining of single crystal silicon, it nonetheless has its own limitations in thin film properties. The maximum film thickness that can be deposited from CVD techniques are limited to several microns, so that thicker structures must be built up from sequential depositions. Thicker device layers are required for dynamic optical elements where dynamic deformations can impact optical performance, and for optical elements which require additional thin film coatings that can cause stress-induced curvature. The thin film mechanical properties, such as Young's modulus and Poisson's ratio, are dependent on the processing parameters and the thermal history of the fabrication process, and can typically vary by as much as 10% from run to run. This is an important limitation for robust manufacturability where these thin film mechanical properties can be a critical parameter for device performance.
[0007] An additional limitation of conventional surface micromachining is that holes through the mechanical elements must be included in the design to allow the etchants used to release the mechanical elements to reach the sacrificial layers. While this is not an important limitation for optical elements such as Fresnel lenses and diffraction grating that include holes in their design, it is an important limitation for optical elements such as mirrors where holes are a detriment to optical performance. Flatness and reflectivity are also important optical design criteria that can be impacted by conventional surface micromachining processes. Thin film stresses and stress gradients, typical of polysilicon thin films, can lead to warping of optical surfaces. In addition the surface of as-deposited polysilicon thin films is not polished, and thus requires post-processing Chemical Mechanical Polishing (CMP) techniques to obtain an optical quality surface finish.
SUMMARY OF THE INVENTION
[0008] The present invention provides a micromechanical or microoptomechanical structure. The structure is produced by a process comprising defining a structure on a single crystal silicon layer separated by an insulator layer from a substrate layer; depositing and etching a polysilicon layer on the single crystal silicon layer, with remaining polysilcon forming mechanical or optical elements of the structure; exposing a selected area of the single crystal silicon layer; and releasing the formed structure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 illustrates in perspective view a MEMS device having various optical and mechanical elements formed in accordance with the process of the present invention; and
[0010] [0010]FIG. 2 is a cross-sectional view of a silicon-on-insulator (SOI) wafer in which MEMS and MOEMS devices can be created according to the present invention;
[0011] FIGS. 3 - 18 show an embodiment of process steps used to form a MEMS device such as those illustrated in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0012] Described below is an embodiment of the present inventive process and device. The embodiment illustrates only one of the several ways the present invention may be implemented. Although the embodiment is described in the context of a moving mirror on a silicon-on-insulator (SOI) chip, it could easily be used for other components. In the description that follows, like numerals represent like elements or steps in all figures. For example, if the numeral 10 is used in a figure to refer to a specific element or step, the numeral 10 appearing in any other figure refers to the same element.
[0013] [0013]FIG. 1 illustrates some of the very complex microelectromechanical (MEMS) and microoptoelectromechanical (MOEMS) devices that can be constructed on a silicon wafer using the embodiment of the present invention. The device 200 includes movable optical elements constructed from single crystal silicon overlaying an insulator such as a diffraction grating 202 , a grating 204 , and a Fresnel lens 206 . Active electronic elements can also be defined in the single crystal silicon layer, including flip chip bonded light producing laser diodes 201 , light detecting photodiodes 203 , or conventional CMOS logic circuitry 205 . Bulk modifications required for packaging or mounting of the substrate are also possible, such as illustrated by etched cavity 208 , and added polysilicon layers can be used for mechanical elements such as hinges 209 .
[0014] [0014]FIG. 2 shows an embodiment of a silicon-on-insulator (SOI) wafer 10 suitable for use in the embodiment of the process described herein. The SOI wafer 10 includes a thin single crystal silicon device wafer layer 12 , and a substrate layer 14 . The substrate layer 14 is preferably polysilicon. Between these two layers 12 and 14 there is a buried oxide (BOX) layer 16 that integrally bonds the device layer 12 and the substrate layer 14 . This buried oxide layer 16 can also be used as an etch stop in wet and dry etching procedures to form a thin membrane. In addition, there is a back oxide layer 18 on the back side of the substrate layer 14 , which is used to control etch down to the interface between the device layer 12 and substrate layer 14 from the backside. Preferably, the wafer is circular with a diameter of 100 mm±0.5 mm and a thickness of 525±25 microns. The overall thickness of the wafer is made up of 1±0.5 microns of backside oxide 20 , 1±0.05 microns of buried oxide (BOX), and 5±0.5 microns of single crystal silicon. The remainder of the thickness is made up of the substrate.
[0015] Before beginning processing, the wafer is inspected to verify that it meets the manufacturer's specifications. If it meets the specifications, the wafer is inscribed with a lot and wafer number, cleaned, and 2000Å of thermal oxide 20 are grown on top of the single crystal silicon layer 12 to act an etch stop in a later polysilicon etch and to prevent doping of the SCS by a later polysilicon glass (PSG) layer.
[0016] FIGS. 3 - 18 , considered in conjunction with the following detailed steps 1 - 84 , illustrate an embodiment of a process used on the wafer of FIG. 2 to produce the grating 204 of the microstructure 200 illustrated in FIG. 1. The process illustrated below can also be used for other types of components; it all depends on what is patterned into the wafer. The patterning of the structures on the wafer is done using standard photolithography techniques well known in the art, which typically comprise depositing layers of the correct materials on the wafer, applying a photoresist on the wafer, exposing the photoresist in areas to be added (light mask) or removed (dark mask) and then performing the appropriate etch.
Step # Process Comments 1. Thermal oxidation 1000° C., 2000 Å 2. Photolithography a) bake 110 degree C., 15 min Mask #1: Substrate — b) HMDS, 5.OK, 30 sec Contact c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 3. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 4. SCS etch RIE: HBr, Cl 2 , target etch rate: 5000 Å/min 5. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 6. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 7. Photolithography a) bake 110 degree C., 15 min Mask #2: SCS_Dimple b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 8. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 9. SCS etch RIE: HBr, Cl 2 , target etch rate: 5000 Å/min 10. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 11. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 12. Polysilicon deposition LPCVD, 3 μm 13. Polysilicon etch RIE: HBr, Cl 2 , target etch rate: 5000 Å/min 14. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 15. Photolithography a) bake 110 degree C., 15 min Mask #3: SCS_Grating b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 16. SCS etch RIE: HBr, Cl 2 , target etch rate: 5000 Å/min 17. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 18. Photolithography a) bake 110 degree C., 15 min Mask #4: SCS_Hole b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C, 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min 19. SCS etch RIE: HBr, Cl 2 , target etch rate: 5000 Å/min 20. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 21. TEOS deposition LPCVD, 8 μm 22. Densification 800° C., 1 hour 23. CMP Leave 2 +/− 0.2 μm 24. Photolithography a) bake 110 degree C., 15 min Mask #5: Anchor_SCS b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 25. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 26. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 27. Nitride deposition LPCVD, 6000 Å 28. Photolithography a) bake 110 degree C., 15 min Mask II 6: Nitride — b) HMDS, 5.OK, 30 sec Struct c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 29. Nitride etch RIB: CF 4 , target etch rate: 2500 Å/min 30. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 31. Polysilicon deposition LPCVD, 5000 Å 32. Photolithography a) bake 110 degree C., 15 min Mask #7: Poly0_Struct b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 33. Backside polysilicon RIE: SF 6 , O 2 strip 34. Polysilicon etch RIE: HBr, Cl 2 , target etch rate: 5000 Å/min 35. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 36. PSG deposition PECVD, 2 μm 37. Photolithography a) bake 110 degree C., 15 min Mask #8: Poly1_Dimple b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 38. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 39. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 40. Photolithography a) bake 110 degree C., 15 min Mask #9: PSG1_Hole b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 41. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 42. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 43. Polysilicon deposition LPCVD, 2 μm 44. PSG deposition PECVD, 2000 Å 45. Anneal 1000° C., 1 hour 46. Backside polysilicon RIE: SF 6 , O 2 strip 47. Photolithography a) bake 110 degree C., 15 min Mask #10: Poly1_Struct b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 48. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 49. Polysilicon etch RIE: HBr, Cl 2 , target etch rate: 5000 Å/min 50. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 51. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 52. Oxide deposition PECVD, 7500 Å 53. Photolithography a) bake 110 degree C., 15 min Mask #11: PSG2_Hole b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 54. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 55. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 56. Photolithography a) bake 110 degree C., 15 min Mask #12: PSG2 — b) HMDS, 5.OK, 30 sec PSG2_Hole c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 57. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 58. Strip photoresist Hot PRS2000, 20 min rinse DI water, 5 min spin, dry 59. Polysilicon deposition LPCVD, 1.5 m 60. Oxide deposition PECVD, 2000 A 61. Anneal 10000C, 1 hour 62. Photolithography a) bake 110 degree C., 15 min Mask #13: Poly2_Struct b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 63. Backside polysilicon RIE: SF 6 , O 2 strip 64. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 65. Polysilicon etch RIE: HBr, Cl 2 , target etch rate: 5000 Å/min 66. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 67. Strip photoresist Hot PRS2000, 20 min 68. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 69. Photolithography a) bake 110 degree C., 15 min Mask #14: SCS_Expose b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 70. Oxide etch HF 71. Photolithography a) bake 110 degree C., 15 min Mask#15: Thick_Metal b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 72. Metal evaporation Cr/Au: 300 Å/5000 Å 73. Lift-off Hot 1112A 74. Photolithography a) bake 110 degree C., 15 min Mask#16: Thin_Metal b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DL water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 75. Metal evaporation Cr/Au: 200 Å/300 Å 76. Lift-off Hot 1112A 77. Photolithography a) bake 110 degree C., 15 min Mask #17: Back b) HMDS, 5.OK, 30 sec c) AZ1813, 4.OK, 30 SEC, 1.3 um d) softbake 90 C., 30 min e) expose, 5.0 mW/cm 2 , 12 sec f) develop MF 319, 1.1 min g) rinse, DI water, 4 min h) spin dry i) hardbake 110 degree C., 30 min 78. Nitride etch RAE: CF 4 , target etch rate: 2500 Å/min 79. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min 80. Protect front side Spin-on coat (proprietary) 81. Strip photoresist Hot PRS2000, 20 min (backside) rinse DI water, 5 min spin, dry 82. KOH etch 45%, 65-85° C. 83. Nitride etch RIE: CF 4 , target etch rate: 2500 Å/min 84. Oxide etch RIE: CF 4 , target etch rate: 2500 Å/min
[0017] [0017]FIG. 3 illustrates the wafer at the conclusion of step 6 . Substrate contact holes 22 about 4 microns wide are patterned onto the SCS layer 12 of the wafer. A reactive ion etch (RIE) of the thermal oxide 20 is performed, and the SCS layer 12 is etched through to the buried oxide 16 , also using a reactive ion etch. The photoresist used to pattern the holes 22 is left on to protect the rest of the oxide 20 , and an RIE etch of the exposed buried oxide 16 is performed 1 micron down. This etches the BOX layer 16 away and leaves the substrate layer 14 exposed at the bottom of the contact holes 22 .
[0018] [0018]FIG. 4 illustrates the state of the wafer at the conclusion of step 14 . SCS dimple holes 24 4 microns wide are patterned onto the SCS layer 12 and an RIE etch of the thermal oxide 20 is performed, followed by an RIE etch of the SCS layer 12 through to the BOX layer 16 . The photoresist is left on to protect the rest of the thermal oxide 20 and an RIE etch of the exposed BOX layer 16 is performed until about half the thickness of the BOX layer is etched away. The photoresist is removed and polysilicon 26 is deposited to fill the dimple 24 and substrate contact holes 22 . In this embodiment, 2.5 microns of polysilicon should be enough, since the dimples 24 and substrate contacts 22 are 4 microns wide. The polysilicon 26 is etched with an RIE using the thermal oxide 20 as an etch stop. This removes the polysilicon 26 from everywhere except in the dimple and substrate contact holes, where the level of the polysilicon will be lower than the rest of the wafer, depending on the amount of polysilicon overetch.
[0019] [0019]FIG. 5 illustrates the state of the wafer at the conclusion of step 17 . A pattern in the form of a grating 28 is first applied to the SCS layer 12 . The grating 28 must be applied to the wafer at this early stage of processing. Optimum focusing of the applied mask is needed because the line spacing of the grating is of the same order as the wavelength of light, meaning that the resolution must be as good as possible. To assure optimum focus, the grating 28 must be applied to the wafer when there is little or no topography already built up. This ensures that there are no problems with depth of focus that would affect the quality of the resulting grid. In addition, applying the grid while there is minimum topography on the wafer ensures that there are no adverse effects from shadows cast by topographical features that are present. Once the grating 28 is patterned on the wafer, a quick RIE oxide etch is then performed to remove the thermal oxide 20 , followed by a 3 micron RIE etch of the SCS layer 12 . The photoresist used to apply the grating 28 is then removed.
[0020] Various types of gratings 28 can be applied to the SCS layer 12 ; the exact type of grid will depend on the application of the particular micromechanical or microoptomechanical device. Examples of gratings include a Fresnel pattern useful for reflective optical applications; a uniform square grating useful for light frequency division in applications such as a spectrum analyzer; and a variable pitch grid where sets of lines in the grating are spaced in variable increments to achieve better spectral coverage of certain wavelengths and enhance optical power. Different gratings may also be used for other optical purposes, such as a crystal oscillator which changes resonance based on surface effects, or for non-optical purposes such as chemical or biological sensors, where the grating increases the available surface area for chemical or biological binding.
[0021] [0021]FIG. 6 illustrates the wafer at the conclusion of step 23 . The SCS layer 12 is patterned with full-depth features 30 , and a quick RIE etch is performed to remove the thermal oxide 20 . A chlorine-based RIE etch is performed all the way through the SCS layer 12 , using the BOX layer 16 as an etch stop. 0.2 microns of undoped, low pressure chemical vapor deposition (LPCVD) oxide (not shown) are deposited to protect the sidewalls of the full-depth features 30 . Six (6) microns of planarization oxide (POX) 32 are deposited so that the wafer will be flat after later chemical mechanical polishing (CMP); the planarization oxide 32 is preferably boron polysilicate glass (BPSG) or thermally enhanced oxide (TEOS). A timed chemical mechanical polish of the POX 32 is performed until 2±0.2 microns of the planarization oxide 32 remain on the SCS layer 12 .
[0022] [0022]FIG. 7 illustrates the wafer at conclusion of step 27 . A pair of holes 34 are patterned in the POX layer 32 , and an RIE etch is performed to transfer the pattern into the POX 32 and down to the SCS layer. The photoresist is removed and a nitride layer 36 with a thickness of 0.6 microns is deposited via LPCVD. A second nitride layer 38 is also deposited on the back of the wafer for extra selectivity during a later potassium hydroxide (KOH) etch.
[0023] [0023]FIG. 8 illustrates the wafer at the conclusion of step 31 . The resist on the pattern front side is patterned with nitrite structures and the pattern is transferred to the front nitride layer 36 using an RIE etch. A layer of LPCVD polysilicon 40 is deposited on the front, and a similar layer 42 is applied to the back of the wafer; both layers are 0.5 microns thick.
[0024] [0024]FIG. 9 illustrates the wafer at the conclusion of step 36 . The front side of the wafer is patterned with polysilicon structures 44 and then RIE etched to transfer the pattern to the polysilicon layer 40 . The photoresist is left on, the wafer is flipped and another layer of polysilicon (not shown) is deposited on the backside and RIE etched. The wafer is flipped again and the front side resist is removed, which is acting as a protective layer for the front side when flipped. A layer of PECVD polysilicon glass (PSG) 46 is added to the front of the waver and densified to 2 microns.
[0025] [0025]FIG. 10 illustrates the wafer after step 46 . Holes 48 are patterned in the PSG layer 46 and an RIE etch is done to transfer the pattern to the PSG layer using the polysilicon layer 40 as an etch stop. The photoresist is removed and a front layer 50 and back layer 52 of LPCVD polysilicon 2 micros thick are deposited, followed by a deposit of 0.2 microns of PECVD polysilicon glass (PSG) (not shown), and the wafer is annealed at 1,000° C. for one hour to dope the polysilicon layers 50 and 52 and reduce stress.
[0026] [0026]FIG. 11 illustrates the wafer at the conclusion of step 52 . This PSG layer 46 is patterned with polysilicon structures 56 , and an RIE etch is performed to transfer the pattern to a PSG hard mask, followed by an RIE etch to transfer the pattern to the polysilicon layer 50 . The resist is left on and the wafer is flipped and RIE etched to remove the backside polysilicon 52 , using the front side resist and hard mask to protect the front. The wafer is flipped back over when done, the photoresist is removed, and the hard mask is removed with an RIE etch, which thins any exposed oxide by about 0.3 microns. A layer of PECVD polysilicon glass (PSG 2 ) 54 , is deposited and densified to 0.75 microns.
[0027] [0027]FIG. 12 illustrates the wafer at the conclusion of step 55 . Holes 58 are patterned in the PSG 2 layer 54 and an RIE etch is performed to transfer the pattern to the PSG, using the polysilicon layer as an etch stop. The photoresist is then removed.
[0028] [0028]FIG. 13 illustrates the wafer at the conclusion of step 68 . The thermal oxide layer 20 is patterned with polysilicon structures and an RIE etch is performed to transfer the pattern to the PSG hard mask. An RIE etch is performed to transfer the pattern to the polysilicon 54 . The wafer is flipped and an RIE etch is performed to remove the backside polysilicon, using the front side resist and hard mask to protect the front. The resist is removed, and the hard mask is removed with an RIE etch.
[0029] [0029]FIG. 14 illustrates the wafer at the conclusion of step 70 . Areas on the front side where the POX 32 should be removed are patterned. This layer should only be used in areas where there is no polysilicon or metal, since those would act as etch stops for the subsequent etches. A wet etch is performed to remove the thermal oxide layer 20 , exposing selected areas of the SCS layer 12 . Designers must be careful that there nearby structures aren't damaged by a hydrofluoric acid (HF) etch. Polysilicon layers previously put on the SCS layer can be etched away without etching any of the SCS layer because the SCS layer 12 itself creates an etch stop.
[0030] Exposure of selected areas of the SCS layer at this point in the process allows mechanical, electrical and optical strcutures to be built directly onto the selected areas after other important structural (i.e., non-sacrificial) features have been built onto the SCS. These mechanical, electrical and optical structures are thus better able to take advantage of the SCS layer's useful properties. In the embodiment shown, a metal coating 60 is applied directly onto the grating 28 previously etched into the SCS layer 12 (see FIG. 15). Application of the metal coating 60 turns the grating 28 into a reflecting grating. Similarly, metal elements can be put on the SCS layer to conduct electrical current, insulating elements can be built on the SCS using nitride or oxide layers, or elements comprising both conducting and insulating parts can be built onto the SCS layer.
[0031] [0031]FIG. 15 illustrates the wafer at the conclusion of step 76 . A photoresist is patterned for lift-off metal and 0.5 microns of metal 60 are deposited on the grating 28 on the front side of the SCS layer 12 . The resist is lifted off, removing metals in those areas. A pattern is applied with areas where metal should be removed, and 200 Å of chromium (Cr) are deposited on the front side of the grating 28 , followed by 300 Å of gold (Au). In this case, the gold increases the reflectivity of the grating, and because of how it is deposited it also smoothes the edges of the grating. Other metals having required reflectivity may also be used on the grating 28 ; examples include aluminum (Al) and platinum (Pt). The resist and the metal coating resist are then removed.
[0032] [0032]FIG. 16 illustrates the wafer at the conclusion of step 84 . The backside nitride/oxide layer 38 is patterned with holes sized so that KOH will etch the desired depth. Uncertainty in wafer thickness will affect the size of the holes created at the other side of the wafer. The pattern is transferred to the nitride layer 38 with an RIE etch, and the same pattern is also transferred to the oxide layer 18 with an RIE etch. A through-wafer KOH etch is performed while protecting the front side with a deposited layer. If a coating is used it should be left on for the next step which involves removing the backside nitride/oxide using a nitride RIE etch and then an oxide RIE etch, which clears off exposed buried SCS. The protective layer possibly present from the last step will protect the front side. Backside etching of the wafer 10 is possible because in this process because of the use of different materials for the substrate layer 14 (which is made of polysilicon) and the device layer 12 (made of single crystal silicon). This enables the substrate to be etched away without etching away the backside of the device layer, and allows both sides of the device layer to be used to make various components mechanical and optical components such as the two-sided mirror shown.
[0033] To make the two-sided grating 204 , a blanket deposit of 0.1 microns of metal 62 is deposited on the backside of the wafer to metalize the backside of the mirror. The metal is sputtered onto the backside of the wafer; suitable metals for metalization of the backside include all the metals used on the front layer 60 . If the component whose backside is to be metalized has holes which extend through the device layer, the backside metal must be deposited carefully to ensure that the metal does not flow through the holes and ruin the quality of the front surface of the device. This is particularly important with optical components, where the front surface must have near-perfect optical qualities and no flow-through from back to front can be tolerated. An effective way of addressing this problem of metal flowing through to the front surface is to tilt the wafer while the metal is sputtered onto the backside; this prevents flow-through of the metal. Any exposed holes in the SCS layer 12 must be kept small (approximately 2 microns) to prevent sputtered metal from traveling all the way through the wafer. The same technique can be used when sputtering metal on the front side of the wafer if a two-sided optical component is needed.
[0034] Metalization of the backside of a component such as the grating 204 has several advantages. Among other things, the backside metalization helps with the release of the component once it's finished. When used on a one-sided optical device such as a mirror, backside metalization reduces transmission of light through the mirror. Backside metalization also helps ensure that any residual stresses in the mirror are balanced, so that the grating 204 will not become distorted. Finally, backside metalization allows two-sided optical components to be made.
[0035] [0035]FIGS. 17 and 18 illustrate the wafer at the conclusion of the process after the grating 204 built into the wafer has been released. The release may be performed by any of various methods including standard MUMPS methods which include (1) stripping the photoresist by soaking in acetone for 20 to 30 minutes with mild agitation, (2) etching in 49% straight HF for 2 ½ to 3 minutes and rinsing in de-ionized water for 10 minutes, or (3) rinse in IPA for 5 minutes and bake the chip at 100-110° C. for 10 to 15 minutes.
[0036] Since the fabrication technology utilized to produce microoptoelectromechanical (MOEMS) components can lead to manufacturing barriers in the thin film properties associated with the process, the present invention includes an enabling fabrication process for microoptoelectromechanical systems that overcomes the barriers in the optomechanical properties of thin film structures. The key innovation to overcoming these thin film properties is to utilize silicon on insulator (SOI) wafers as the starting substrate in a surface micro-machining process (see FIG. 1). SOI is a generic term that refers to a structure in which a silicon layer is supported by a dielectric material. In this embodiment, a silicon device layer, bonded to a conventional silicon handle wafer, has a SiO 2 thin-film layer at the interface. This allows critical optical and electronic components to be fabricated in a single crystal silicon device layer, which can be released from the handle wafer by etching the oxide at the interface between the device layer and the substrate.
[0037] The oxide layer at the interface can also be utilized as a backside etch stop layer for releasing optical components, such as a mirror, that cannot include etch holes. The device layer has a user specified thickness that is appropriate for the given application, and has excellent and reproducible electrical and thin film properties. Both the back and front side of the device layer would be polished, and thus optical elements fabricated in this layer do not require additional post-processing chemical-mechanical polish (CMP) techniques to obtain an optical quality surface finish. Since the device layer is single crystal silicon, it has no intrinsic stress or stress gradients in the absence of thin film coatings. Since it can be made thicker than conventional chemical vapor deposition (CVD) deposited thin films, optical components fabricated in this layer have minimal distortions after thin film depositions such as aluminum to increase surface reflectivity, or dielectric thin films to decrease surface reflectivity. The additional thickness is also important to minimize distortions for dynamically actuated optical elements.
[0038] As those skilled in the art will appreciate, other various modifications, extensions, and changes to the foregoing disclosed embodiments of the present invention are contemplated to be within the scope and spirit of the invention as defined in the following claims.
|
The present invention provides a micromechanical or microoptomechanical structure. The structure is produced by a process comprising defining a structure on a single crystal silicon layer separated by an insulator layer from a substrate layer; depositing and etching a polysilicon layer on the single crystal silicon layer, with remaining polysilcon forming mechanical or optical elements of the structure; exposing a selected area of the single crystal silicon layer; and releasing the formed structure.
| 1
|
BACKGROUND OF THE INVENTION
[0001] The invention relates to a device for mixing and dispensing multi-component compositions, in particular for dental purposes, with a cartridge with at least two cylindrical chambers arranged in parallel for receiving the components and in each case a plunger for discharging the components, the chambers having outlet openings which are covered by a cap, which has an outlet tube enclosing a mixing helix, the cap being movable from a position closing the outlet openings into a position releasing them.
[0002] A known device of this type, which however is not intended for dental purposes (EP 0319 135 A2), has two cylindrical chambers, in each of which one component is contained. The chambers are provided on their end face with openings which are closed by a cap. The cap has a sleeve-shaped outlet tube, which encloses a mixing helix. The cap initially closes the openings of the chamber. If the two-component composition is to be dispensed, the cap is pulled, so that it moves away a little from the cartridge with the two chambers and releases the outlet openings. With the aid of plungers in the chambers, on which pressure is exerted, the components can then be pressed into the cap and from there into the sleeve-shaped outlet tube. While passing through this outlet tube, the components are mixed by the mixing helix.
[0003] Such devices are also very expedient for dental purposes. There is no need to provide a separate closure cap that has to be removed and replaced with a cap which contains the outlet tube and the mixing helix. However, a disadvantage of such devices is that a separate manipulation is required for pulling the cap to bring it into the open position. This is not only laborious; there is also the risk of inadvertently pulling the cap off entirely. Problems also arise in the production of such already known devices. As far as possible, the same model of the cartridges is intended to be supplied with different caps. Depending on the intended application, straight or curved outlet tubes are required. These caps must then also be respectively provided with a mixing helix, making them relatively expensive parts. Furthermore, the fitting of the mixing helix in the cap is not entirely simple.
[0004] The object of the invention is to provide a device of the type stated at the beginning which can be operated easily and unproblematically and allows low-cost and practical mass production.
SUMMARY OF THE INVENTION
[0005] The solution according to the invention comprises that the cap can be moved into the open position by the pressure of the components while they are being discharged and that a transverse wall which extends toward the cap and on which the mixing helix is fitted is provided on the cartridge between the outlet openings.
[0006] There is consequently no longer any need to pull the cap. Rather, it has an inner surface, opposite from the cartridge, which is large enough for the pressure of the components when they are being discharged to move the cap into the open position. The mixing helix is in this case fitted on the cartridge and not on the cap. For this purpose, it is fitted on a transverse wall, which has the further advantage that the two or more components cannot easily get into the chamber of the other component respectively during the dispensing operation, and for example cause hardening, and consequently make the device unable to operate.
[0007] The cap is expediently rotatable with respect to the cartridge, since, in the case of a curved outlet tube, the operator can then set this outlet tube in the way most expedient for him. However, the rotatability is only ensured when the cap has been moved into the open position. For this purpose, with the cap closed, the transverse wall is enclosed by the cap or is gripped by it on both sides in such a way that turning is not possible. As a result, it is possible to form the inner surface regions of the cap, which are intended to close the outlet openings of the chambers, optimally for this purpose.
[0008] If the mixing helix is flexible, caps with outlet tubes that have different curvatures can be used.
[0009] The device expediently has latching means for the closed and open positions. In this case, the latching means for the closed position must of course be adapted in its holding force to the opening force produced by the pressure of the components, in order that the cap can actually be opened just by pressure exertion and it does not have to be pulled.
[0010] The latching means for the open position expediently has a greater holding force than the latching means for the closed position, since otherwise there is the risk of the cap being detached completely from the cartridge if, after opening, the operator does not reduce the force which is required for opening. For this purpose, it may be provided that the latching means for the open position is a snap-action latching means, which provides a greater force of resistance opposing a further opening movement of the cap than a closing movement. For this purpose, surfaces which are for example sawtooth shaped in cross section may be provided, the sloping surfaces making it easier for the cap to be pushed onto the cartridge, but the surfaces perpendicular to the axis then preventing the cap from being detached when there is a movement in the opposite direction, that is for pulling off the cap.
[0011] Although the device may be designed for more than two components, it is designed particularly expediently for two components and correspondingly with two chambers. The device according to the invention is suitable in particular for once-only use. It can also be made to be relatively small and be actuated by a discharging device or, with the aid of an adapter, by means of a relatively large pair of grippers. The discharging device or the adapter may in this case be formed with surfaces which securely hold the cap, so that the latter cannot move any further after opening, become detached from the cartridge and get into the patient's mouth.
[0012] A means 19 for distributing or uniformly applying/introducing the multi-component composition is advantageously provided at the outlet end of the outlet tube 12 . This means 19 may be a brush, a small sponge, a nozzle, a spatula or the like. The means 19 may be formed as an additional attachment which is attached onto the outlet tube 12 . The means 19 may, however, also be formed in one piece with the outlet tube 12 .
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The invention is described below by way of example on the basis of an advantageous embodiment with reference to the accompanying drawings, in which, in a perspective, partly cut-open view:
[0014] [0014]FIG. 1 shows the device in the closed state;
[0015] [0015]FIG. 2 shows the device, partly cut open, in the open state;
[0016] [0016]FIG. 3 shows detailed views in the section of the embodiment of FIGS. 1 and 2;
[0017] [0017]FIG. 4 shows detailed views of a slightly different embodiment;
[0018] [0018]FIG. 5 shows the use of the device according to the invention in a pair of discharging grippers with an adapter;
[0019] [0019]FIG. 6 shows details in section of the adapter of FIG. 5 with the device according to the invention fitted;
[0020] [0020]FIG. 7 shows in section an outlet tube with a 10 means for distributing the finished multi-component composition;
[0021] [0021]FIG. 8 shows in a perspective view another embodiment with a means for distributing the finished multi-component composition; and
[0022] FIGS. 9 - 20 show further views and embodiments.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] The device of the invention, which is shown in FIGS. 1 and 2, has a cartridge 1 , which comprises two cylindrical chambers 2 , arranged in each of which are a component (not shown) and a plunger 3 (FIG. 2), by which pressure can be exerted from the bottom (in the figures) upward by a suitable implement, in order to press the components upward through channels 4 and openings 5 . These openings are provided on a circular surface 6 , which is subdivided by a transverse wall 7 . The surface 6 is in this case located on a circular-cylindrical projection of the cartridge which has an annular bead 9 . Fitted on this cylindrical projection 8 is a cap 10 , which has on its inner wall annular recesses 11 , which interact with the annular bead 9 . The cap 10 has a curved outlet tube 12 , which encloses a mixing helix 13 , which is fastened on the transverse wall 7 . In the closed state, which is shown in FIG. 1, the annular bead 9 engages in the upper annular recess 11 of the cap 10 . The substantially circular inner surface of the cap 10 in this case covers over the openings 5 , so that the chambers 2 are closed. The transverse wall 7 is securely held against twisting in a recess 20 , which can be seen in FIG. 2. If pressure is exerted on the plungers 3 , and consequently the components, the cap is moved by this pressure from the position shown in FIG. 1 into the position shown in FIG. 2. The cylindrical inner surface of the cap 10 thereby moves away from the outlet openings 5 , so that the components can emerge. The components are in this case separated from each other by the transverse wall 7 , so that one component cannot readily get into the chamber 2 of the other component respectively. The transverse wall 7 is then no longer held by the recess 20 , so that the cap 10 can be turned and the operator can turn the outlet tube 12 into the direction that is particularly expedient for him.
[0024] [0024]FIG. 3 shows detailed representations of how the cap 10 is securely held with the aid of the annular bead 9 and the recesses 11 . At the top it is shown at A that the annular bead is located in the upper recess 11 , that is to say, the cap 10 is assuming its lower position and closing the openings 5 . In the case of the representation B, the cap has moved upward and is held in this open position at its lower recess 11 by the bead 9 .
[0025] The embodiment of FIG. 4 differs from that of FIG. 3 in that the bead 9 of the cylindrical projection 8 of the cartridge has a lower straight surface, the lower recess 11 of the cap 10 likewise having a corresponding straight surface. The interaction of these straight surfaces prevents the cap 10 from being able to move further upward from the open position shown at B in FIG. 4. As a result, flipping off of the cap 10 , for example into the patient's mouth, is prevented.
[0026] Shown in FIG. 5 is an adapter 14 , which has an upper opening into which the cartridge 1 with the cap 10 and the outlet tube 12 can be fitted. This adapter 14 may in turn be fitted onto a pair of grippers 18 , which are intended for other, in particular larger cartridges, and are commercially available.
[0027] [0027]FIG. 6 shows in section the adapter 14 with the cartridge 1 fitted. An overall view is shown at A, detailed views are represented at B and C. In the case of the position of B in FIG. 6, the cartridge 1 is hindered from upward movement at its base part 15 by a stop face 16 when pressure is exerted on the plungers 3 . A further stop face 17 prevents the cap 10 from any further upwardly directed movement when it moves from the closed position (at B in FIG. 6) into the open position (at C in FIG. 6). Consequently, this stop face 17 reliably prevents the cap 10 from being able to flip off. The adapter has in this case the advantage that the device according to the invention can also be used with other commercially available grippers. It goes without saying that this is not intended to exclude the possibility of also providing special grippers for the devices according to the invention, these grippers then also being covered by the extent of protection of this patent.
[0028] Shown in FIG. 7 is a cross section through another embodiment of the outlet tube 12 , in which a device 19 is arranged at the outlet end of the same for distributing or spreading the discharged multi-component composition. The device 19 for distributing or spreading can be a brush (FIGS. 7, 8, 9 , 10 , 17 , 18 ), a small sponge (FIG. 11), a brush (FIG. 12), a nozzle (FIGS. 13, 19, 20 ), a spatula (FIG. 14) or a similar device.
[0029] By contrast with the embodiment of FIG. 7, in the case of the embodiment of FIG. 8 the means 19 for distributing the finished multi-component composition onto the outlet tube 12 has been fitted, so that various parts 19 can optionally be fitted here on the outlet tube 12 . This is shown also in the embodiment of FIGS. 15 and 16.
|
The device for mixing and dispensing multi-component compositions is distinguished in that a cap ( 10 ) acting as a closure initially closes the outlet openings ( 5 ) of the components and can be moved into the open position by pressure of the components while they are being discharged, so that the components can be mixed by the mixing helix ( 13 ) and emerge from the outlet tube ( 12 ).
| 0
|
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates in general to a method and system for including file export information within a corresponding file system. Still more particularly, the present invention relates to a method and system for including export information in a file system extended attributes data area.
2. Description of the Related Art
The Network File System (NFS) is a distributed file system that allows users to access files and directories located on remote computers and treat those files and directories as if they were local. For example, users may use operating system commands to create, remove, read, write, and set file attributes for remote files and directories. NFS provides services through a client-server relationship. Computers that include file systems, or directories, or other resources available for remote access are called servers. Computers that use a server's resources are considered clients.
The act of servers making file systems available for clients is called exporting. In traditional network file systems, a server has an export file that includes NFS information for file systems being accessed by the server. Upon boot-up, the server loads the export file into a kernel. The network file system kernel then performs a file system mounting process which makes the mounted file systems available for authorized clients.
If two servers access the same file systems on the same disk, each server has individual export files that are maintained by a system administrator. The export file includes information about the file system such as the location of file systems (pathname), who has access privileges, and if the file system is write protected. If a change in the export information is preferred, the system administrator modifies the export file on both servers. For example, if a new user is added to the access list for a file system, the system administrator adds the new user to the export file on both servers.
A challenge found in traditional systems is the ability to manage export information due the dynamics of a distributed network such as NFS. Tasks such as adding, deleting, relocating and changing file system export information often cause system administrators to update multiple export files. Each server has an export file that includes export information for file systems maintained by the server. If a file system's export information changes, the system administrator makes changes to the export file for each server that supports the file system.
Another challenge found in traditional systems is during back-up and restore operations. When file systems are backed-up, the export information is not backed-up and linked to the corresponding file system. When the file system is restored, the export information needs to be added to the export file on the server. Adding the export information often includes the system administrator performing manual processes to add the appropriate export information.
What is needed, therefore, is a way to reduce file export information maintenance by including export information as part of the file system itself.
SUMMARY
It has been discovered that by including NFS export information in a file system extended attributes data area, maintenance of the export information is reduced. The file system includes information about the files as well as an optional data area, called “extended attributes” for storing additional information about the file. In IBM's AIX™ operating system, the extended attribute data area is capable of storing thousands of additional bytes of information pertaining to data files. The export information is included in the file system itself and not in the export file on a server. When a new file system is created, the system administrator determines the file export information and provides it to the corresponding file system extended attributes. The system administrator determines export information that includes the location of the file system (pathname), who has access privileges, and if the file system is write protected. If the file system export information needs to be changed, the system administrator updates the export information in the file system extended attribute data area. For example, the system administrator updates the export information in the extended attribute data when a new user is allowed access to the file system. The system administrator can also select if he wants to have the NFS export information automatically provided to the kernel during a file mount. If the system administrator wants more control of what is exported, he may manually export the file.
Upon boot-up, the server issues mount commands to the file systems it wants to have access to. When the mount command is received, the file system provides export information included in the extended attributes to the kernel whereupon the kernel exports the file system. This makes the maintenance of the file exports automatic on file system mount and unmount. It also makes it easier to backup, replicate, and restore file systems. For example, when the system administrator backs up a file, the export information in the extended attributes is backed-up as well. When the file system is retrieved, the export information is also retrieved within the extended attributes.
The foregoing is a summary and thus contains, by necessity, simplifications, generalizations, and omissions of detail; consequently, those skilled in the art will appreciate that the summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the present invention, as defined solely by the claims, will become apparent in the non-limiting detailed description set forth below.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be better understood, and its numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings. The use of the same reference symbols in different drawings indicates similar or identical items.
FIG. 1 is a high level diagram of a computer system with a file system that includes extended attribute data;
FIG. 2A is a diagram of a file being duplicated from one non-volatile storage area to another;
FIG. 2B is a diagram of a non-volatile storage area providing information to a primary computer system and back-up computer system;
FIG. 3 is a flowchart showing the system boot-up and file exporting process;
FIG. 4 is a flowchart showing the export information being provided from a file system extended attributes data area;
FIG. 5 is a flowchart showing the export information in the extended attributes being modified for a file system;
FIG. 6 is a flowchart showing a computer system responding to a file; and
FIG. 7 is a block diagram of an information handling system capable of performing the present invention.
DETAILED DESCRIPTION
The following is intended to provide a detailed description of an example of the invention and should not be taken to be limiting of the invention itself. Rather, any number of variations may fall within the scope of the invention which is defined in the claims following the description.
FIG. 1 is a high level diagram of a computer system with a file system that includes extended attribute information. Computer system 100 includes an operating system for controlling the operation of the system. Computer system 100 also includes a Network File System (NFS) 170 and network file system kernel 175 that is used for managing files being mounted and exported. Upon bootup, server 100 issues mount command 110 to file system 130 . Mount commands can also be performed by a user, operator, or automated process after the system has booted up. Files and information about files within file system 130 are stored on nonvolatile storage device 120 , such as a disk drive. Nonvolatile storage device 120 can be included with a computer system or can be a separate device accessible to one or more computer systems using a computer network. File system 130 includes file object 140 which includes data stored in files. For example, in a word processing application file object 140 would store the data entered by the user, such as a report, article, or the like. File system 130 manages information about the files maintained by the file system. Some file system data is maintained as file system data, such as the location of specific files, the name of the files, the length of the files, etc. File system 130 also includes extended attribute data 150 that correspond to file object 140 . To conserve nonvolatile storage space, extended attributes are often optional attributes that pertain to a particular application or process. Extended attribute data 150 includes optional data pertaining to file object 140 that is maintained by the file system but provided by the system administrator, user, or application program. Extended attribute data 150 includes export information 155 that corresponds to file object 140 . Examples of what information is included in export information 155 are the pathname of file system 130 , access privileges of file system 130 , and write protection privileges of file system 130 . Files that have been identified to be shared, or exported, to other computer systems include export information in their corresponding extended attributes while other files that have not been identified to be exported do not include the export information within their corresponding extended attributes. When file system 130 receives mount command 110 from computer system 100 , file system 130 provides export information 160 to file system kernel 175 whereupon file system 130 is mounted and exported.
FIG. 2A is a diagram of a file being duplicated from one non-volatile storage area to another. Nonvolatile storage area 200 includes file system 210 . File system 210 includes file object 215 which includes any variety of data that is stored in a computer file. For example, in a word processing application file object 215 would store the data entered by the user, such as a report, article, or the like. File system 210 also includes extended attribute data 220 that correspond to file object 215 . Extended attribute data 220 includes data pertaining to file object 215 that is maintained by the file system or system administrator. Extended attribute data 220 includes export information 225 that corresponds to file object 215 .
When file system 210 is copied (process 230 ) to file system 211 on nonvolatile storage device 240 , file object 215 is copied to file object 216 on nonvolatile storage device 240 , extended attribute data 220 is copied to extended attribute data 221 , and export information 225 is copied to export information 226 . File system 211 maintains information about file object 216 , such as the address of the file on nonvolatile storage device 240 , the name of the file object, etc. For example, when a file is copied during standard back-up the file and the file system are stored on a backup media, such as a magnetic tape. When the file is restored from the backup media, the corresponding export information is also restored along with the file system. Another example of when a file is copied is during support replication used to accurately recreate a situation in order to analyze problems occurring with the computer system. When the file is copied to a non-volatile storage area for support replication, the export information is also copied.
FIG. 2B is a diagram of a non-volatile storage area providing information to a primary computer system and back-up computer system. In this example, the export information is used so that multiple computer systems, often servers, can access and manage the same files stored on a common nonvolatile storage area. Upon boot-up, primary computer system 280 receives export information 285 from extended attribute data corresponding to file object 276 and mounts the file. As long as primary computer system 280 is operational, back-up computer system 290 may not receive information from non-volatile storage area 270 . When primary computer system 280 is not operational, back-up computer system 290 receives export information 295 from extended attribute data corresponding to file object 276 and mounts the file. For example, if a power outage caused primary computer system 280 to become inoperable, back-up computer system 290 takes over as the computer system to support users. In addition, some files are used by many computer systems simultaneously. In these situations, many computer systems would be able to access file 276 using corresponding export information 278 .
FIG. 3 is a flowchart showing the system boot-up and export process. System boot commences at 300 , whereupon a determination is made as to whether a system administrator chooses to automatically provide export information to a network file system kernel during a system boot (decision 310 ). If the system administrator chooses to automatically provide export information, decision 310 branches to “yes” branch 312 whereupon a mount command is issued (step 315 ) and export procedure is processed (pre-defined process block 330 , see FIG. 4 for further details). On the other hand, if the system administrator does not choose to automatically provide export information, decision 310 branches to “no” branch 313 whereupon a determination is made as to whether a mount command is issued (step 320 ). For example, mount commands are issued from back-up computer systems after the original boot-up process if the primary computer system becomes inoperable. If a mount command is issued, decision 320 branches to “yes” branch 322 whereupon an export procedure is processed (pre-defined process block 330 , see FIG. 4 for further details). On the other hand, if a mount command is not issued, decision 320 branches to “no” branch 323 whereupon a determination is made as to whether a new file is added or there is a change in export information for an existing file (decision 340 ). If a new file is added or there is a change in export information for an existing file, decision 340 branches to “yes” branch 348 whereupon extended attribute update is processed (pre-defined process block, see FIG. 5 for further details). On the other hand, if a new file is not added or there are no changes to export information for existing files, decision 340 branches to “no” branch 344 bypassing the extended attribute update process.
A determination is made as to whether any more file changes or mount requests (i.e., from the operator, a user, an external computer system, an automated process, etc.) have been received (decision 355 ). If more requests have been received, processing branches to “yes” branch 360 which loops back to process the next request. This looping continues until the computer system is shut down or otherwise stops using export file information, at which time decision 355 branches to “no” branch 370 whereupon processing ends at 395 .
FIG. 4 is a flowchart showing export information being provided from a file system extended attribute data area. Export processing commences at 400 whereupon export information is retrieved (step 430 ) from the extended attribute data area 436 (step 430 ). Extended attributed data area 436 is referenced by file system data 434 that corresponds to the file being exported (file object 432 ). File system data 434 is maintained by the file system and includes system data regarding file object 432 . System maintained data included in file system data 434 includes such things as the date and time file objects were last used, when they were created, the size of the file objects, security information pertaining to the file objects, and name and location of the file objects within the nonvolatile storage device. Information in the export information includes the location of the corresponding file (pathname), who has access privileges (and what type of privileges those users have), and whether the file is read only. The export information is provided to the network file system kernel at step 440 , whereupon the desired file is exported (step 450 ) and processing returns at 460 .
FIG. 5 is a flowchart showing the export information in the extended attributes being updated for a file system. Extended attribute update processing commences at 500 , whereupon system administrator 515 (or a process simulating the export setup activities typically performed by a system administrator) updates the export information for the corresponding file system (step 510 ). For example, when a new user is allowed access to the file system, the system administrator adds the user to the list of authorized users included in the export information. Another example is when a new file is created, the system administrator provides the proper export information.
The updated export information is provided to extended attribute data area 526 (step 520 ). Extended attributed data area 526 is part of file system data 524 that corresponds to file object 522 . File system data 524 is maintained by the file system and includes system data regarding file object 522 . System maintained data included in file system data 524 includes such things as the date and time file objects were last used, when they were created, the size of the file objects, security information pertaining to the file objects, and name and location of the file objects within the nonvolatile storage device.
After the updated file export information is stored in the corresponding extended attribute data area, the updated export information is able to be retrieved from extended attribute data area (step 530 ). The data is provided to the network file system kernel (step 540 ) whereupon the file is exported (step 550 ) and processing returns at 560 .
FIG. 6 is a flowchart showing a computer system responding to a file request. For example, file requests come from a system administrator or an external computer system. File request processing commences at 600 , whereupon file request 610 is received at step 605 . Requested file object 625 is located (step 615 ) from file system 620 . A determination is made as to whether the requested file is located (decision 640 ). If the requested file is not located, decision 640 branches to “no” branch 642 whereupon an error message is returned (step 645 ) to file request 610 whereupon processing ends at 650 . On the other hand, if the requested file is located, decision 640 branches to “yes” branch 648 whereupon extended attributes are located (step 655 ) from file system data 630 corresponding to file object 625 . A determination is made as to whether extended attributes were located (decision 660 ). If the extended attributes are not located, decision 660 branches to “no” branch 662 whereupon an error message is returned (step 665 ) to file request 610 whereupon processing ends at 670 . On the other hand, if extended attributes are found, decision 660 braches to “yes” branch 668 whereupon extended attribute data 635 is retrieved (step 675 ). A determination is made as to whether file request 610 has authorization for file object 625 (decision 680 ). If file request 610 does not have authorization for file object 625 , decision 680 branches to “no” branch 682 whereupon an error message is returned (step 685 ) to file request 610 whereupon processing ends at 690 . On the other hand, if file request 610 has authorization for file object 625 , decision 680 branches to “yes” branch 688 whereupon the pathname and usage data are provided to file request 610 (step 695 ) and processing ends at 699 . In some embodiments, the export data used for processing FIG. 6 is preloaded from the extended attribute data area into a data structure maintained by a network file system (NFS) when a file system is mounted. In these embodiments the NFS makes the determinations regarding file availability, export information, and authorizations based on the preloaded information and returns the appropriate errors or file data to file request process 610 .
FIG. 7 illustrates information handling system 701 which is a simplified example of a computer system capable of performing the copy processing described herein. Computer system 701 includes processor 700 which is coupled to host bus 705 . A level two (L 2 ) cache memory 710 is also coupled to the host bus 705 . Host-to-PCI bridge 715 is coupled to main memory 720 , includes cache memory and main memory control functions, and provides bus control to handle transfers among PCI bus 725 , processor 700 , L 2 cache 710 , main memory 720 , and host bus 705 . PCI bus 725 provides an interface for a variety of devices including, for example, LAN card 730 . PCI-to-ISA bridge 735 provides bus control to handle transfers between PCI bus 725 and ISA bus 740 , universal serial bus (USB) functionality 745 , IDE device functionality 750 , power management functionality 755 , and can include other functional elements not shown, such as a real-time clock (RTC), DMA control, interrupt support, and system management bus support. Peripheral devices and input/output (I/O) devices can be attached to various interfaces 760 (e.g., parallel interface 762 , serial interface 764 , infrared (IR) interface 766 , keyboard interface 768 , mouse interface 770 , and fixed disk (FDD) 772 ) coupled to ISA bus 740 . Alternatively, many I/O devices can be accommodated by a super I/O controller (not shown) attached to ISA bus 740 .
BIOS 780 is coupled to ISA bus 740 , and incorporates the necessary processor executable code for a variety of low-level system functions and system boot functions. BIOS 780 can be stored in any computer readable medium, including magnetic storage media, optical storage media, flash memory, random access memory, read only memory, and communications media conveying signals encoding the instructions (e.g., signals from a network). In order to attach computer system 701 another computer system to copy files over a network, LAN card 730 is coupled to PCI-to-ISA bridge 735 . Similarly, to connect computer system 701 to an ISP to connect to the Internet using a telephone line connection, modem 775 is connected to serial port 764 and PCI-to-ISA Bridge 735 .
While the computer system described in FIG. 7 is capable of executing the copying processes described herein, this computer system is simply one example of a computer system. Those skilled in the art will appreciate that many other computer system designs are capable of performing the copying process described herein.
One of the preferred implementations of the invention is a client application, namely, a set of instructions (program code) in a code module which may, for example, be resident in the random access memory of the computer. Until required by the computer, the set of instructions may be stored in another computer memory, for example, in a hard disk drive, or in a removable memory such as an optical disk (for eventual use in a CD ROM) or floppy disk (for eventual use in a floppy disk drive), or downloaded via the Internet or other computer network. Thus, the present invention may be implemented as a computer program product for use in a computer. In addition, although the various methods described are conveniently implemented in a general purpose computer selectively activated or reconfigured by software, one of ordinary skill in the art would also recognize that such methods may be carried out in hardware, in firmware, or in more specialized apparatus constructed to perform the required method steps.
While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from this invention and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this invention. Furthermore, it is to be understood that the invention is solely defined by the appended claims. It will be understood by those with skill in the art that is a specific number of an introduced claim element is intended, such intent will be explicitly recited in the claim, and in the absence of such recitation no such limitation is present. For non-limiting example, as an aid to understanding, the following appended claims contain usage of the introductory phrases “at least one” and “one or more” to introduce claim elements. However, the use of such phrases should not be construed to imply that the introduction of a claim element by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim element to inventions containing only one such element, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an”; the same holds true for the use in the claims of definite articles.
|
A system and method for including export information in the file system extended attribute data area is provided. File export information is determined by a system administrator or automated process. The determined export information is stored in an extended attribute data area corresponding with the file. When a computer system issues mount commands for the file systems to be mounted, the file system provides export information included in the extended attributes to the kernel whereupon the kernel exports the file system. Maintenance of file export information is thereby reduced. Backup, replications, and restorations of file systems is simplified by maintaining the export information along with the files being backed, replicated, or restored. For example, when the system administrator backs up a file, the export information in the extended attributes is backed-up as well. When the file system is retrieved, the export information is also retrieved within the extended attributes.
| 8
|
BACKGROUND OF THE INVENTION
This invention relates to turbo-charger systems and turbo-charged engines.
A typical turbo-charger system includes a turbine shaft having an exhaust turbine at one end that is driven by exhaust gases from the engine cylinders, and having a compressor at the other end for providing compressed air to the engine. At very high engine loads, the engine may become overcharged and/or overheated, which can be prevented by reducing the inlet air pressure supplied by the compressor turbine. One commonly used method involves the use of an exhaust waste gate connected to the exhaust gas outlet of the engine for extracting some gas directly into the atmosphere instead of by way of the exhaust turbine, to reduce the speed of the compressor. However, such a valve must be made resistent to corrosion from high temperature exhaust gases, and even so is subject to clogging. It may be noted that the exhaust turbine does not tend to clog, probably because of its high speed rotation. Another approach is to utilize a constricter valve in line with the engine air inlet, to reduce the amount of air flow towards the cylinder. However, a constricter increases the back pressure on the compressor, so that the exhaust turbine turns slower. The slower speed of the exhaust turbine results in a higher back pressure for the engine cylinder which reduces efficiency. Still another approach is to utilize a venting air valve on the downpath side of the compressor, to merely vent excessive air into the atmosphere. This approach cannot be utilized where a carburetor is stationed up-path from the compressor, since a valve would exhaust fuel into the atmosphere, which would be dangerous. This venting valve approach can be utilized with fuel injection engines only, and has been known to run turbocharger impellers at dangerously high operational speeds, sometimes causing turbocharger over speeding.
In addition to the above drawbacks of present systems, there is the problem of poor engine response while shifting gears. During rapid acceleration, there is typically a high engine load immediately before the shift, and during the shift there is a momentary closing of the throttle while the turbines lose speed. When the throttle is opened again, it requires a moment for the turbines to pick up speed to supply enough compressed air for rapid acceleration in the new gear. A turbo-charger system which could be utilized on both carburetor and fuel injection engines, which provided high engine efficiency, and which provided good engine response during gear shifting, would be of considerable value in engine design.
SUMMARY OF THE INVENTION
In accordance with one embodiment of the present invention, a turbo-charged engine system is provided which operates reliably and efficiently for both carbureted and fuel injection engines, and which provides good engine response. The turbo-charged engine system is of the type which includes an exhaust turbine that drives a compressor that supplies compressed air to the engine's cylinders. A recirculating passage is provided which can recirculate air from the downstream end of the compressor to the upstream end thereof, and a valve is located along the passage. When the engine load is excessive, the valve opens to recirculate the air to thereby reduce the air pressure at the cylinder inlet. The recirculating valve air causes the compressor to turn at a high speed, so that the exhaust turbine turns at a high speed to minimize the back pressure on the engine cylinder, to thereby increase engine efficiency. In addition, the system provides good response during gear changing in the course of rapid acceleration, when a heavy engine load is encountered immediately prior to the beginning of gear changing, and when the rotating members of the exhaust turbine and compressor will be turning rapidly. After the throttle has been closed during gear changing and is then opened wide, the turbines are still spinning rapidly so that the compressor can supply compressed air to the engine with minimum delay.
The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a turbo-charged engine, constructed in accordance with the present invention.
FIG. 2 is a sectional side view of a recirculating valve constructed in accordance with another embodiment of the invention, which can be utilized with the rest of the engine of FIG. 1.
FIG. 3 is a view taken on the line 3--3 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As illustrated in the figure, a turbo-charged engine 10 includes a cylinder 12 within which a piston 14 reciprocates, an inlet conduit 16 through which air is received into the cylinder, and an outlet conduit 18 through which exhaust gases are exhausted from the cylinder. A valve assembly 10 controls the flow of air and exhaust gases into and out of the cylinder, and the injection of fuel into the cylinder. The term "cylinder" refers to an engine chamber in which combustion occurs, and not to the shape of the chamber which may be, for example, a toroid for a rotary engine.
The engine 10 is of the turbo-charged type wherein an exhaust turbine 22 is located along the exhaust conduit 18 so that it is driven by the exhaust gases. The turbo-charger also includes a compressor or turbine wheel 24 located along the inlet conduit 16 for supplying air above ambient pressure to the cylinder, and a shaft 26 connecting the compressor 24 to the exhaust turbine 22.
In the operation of the fuel injected, turbocharged engine, air passes into an end 16E of the inlet conduit, past a venturi 30, past a fuel metering head 32, past the compressor 24, into a manifold at 16C, and past the valve assembly 20 to the cylinder 12. During engine operation at medium speeds and loads, exhaust gases passing through the outlet conduit 18 drive the exhaust turbine 22 to turn the compressor 24, to thereby supply compressed air to the engine which increases the fuel economy of the engine while also increasing its power output. Under high load conditions, as where a vehicle is accelerating rapidly the turbo-charging could result in damage to the engine if precautions are not taken. That is, during such engine operation, the large amounts of exhaust gases cause the exhaust and turbine and compressor 22, 24 to turn rapidly so that the turbo-charger supplies high pressure air to the cylinder which, when combined with large amounts of fuel, can cause excessive heating of the engine. This is a well recognized problem, and several solutions have been utilized. As mentioned earlier, one solution is to utilize an exhaust waste gate at the exhaust conduit 18 to release exhaust gases directly into the atmosphere without passing through the turbine 22, to turn this turbine more slowly so that less air is compressed by the compressor 24. Another solution is to utilize an escape valve along a portion of the inlet conduit 16 downpath from the compressor 24 to release some of the compressed air to the atmosphere. Another solution is to use a constricter valve along the inlet conduit 16 to limit the flow of air to the cylinder. All of these solutions have affected engine performance, especially during rapid acceleration.
During rapid acceleration of a vehicle, the transmission gear ratio may be changed a plurality of times. Typically, the engine is turning rapidly just before the gear change, but the throttle is then closed at least partially during the gear change. During the brief time that the throttle is closed, the engine slows appreciably because there is considerable load resulting from friction and the like at high engine speed. Following the gear change, the throttle is rapidly opened again. However, the exhaust turbine and compressor 22, 24 will not be spinning rapidly, so that there will initially be a large back pressure along the outlet conduit 18 and a low air pressure along the inlet conduit 16 near the cylinder, all of which lowers engine power and efficiency.
In accordance with the present invention, a recirculating passage 40 is provided which interconnects locations 42, 44 respectively downstream and upstream from the compressor 24. A valve 46 located along the recirculating passage controls the flow of air through the passage. When the engine is operating under a heavy load, so that large amounts of exhaust gas are generated which cause the compressor 24 to spin rapidly and produce a high pressure at the manifold or cylinder end 16C of the inlet conduit, the valve 46 opens to allow much of the compressed air to flow back to the entrance of the compressor 24. This results in a lower air pressure downpath from the compressor at the location 42 and a higher air pressure upstream from the compressor at location 44, so that the compressor can rotate very rapidly. When the engine encounters a heavy load as just before a gear change during rapid acceleration the recirculating valve 46 will be wide open and the compressor 24 will be spinning rapidly. During the brief time when the throttle is then closed for a gear change, the compressor will lose some speed, but will still be spinning rapidly when the throttle is open again following the gear change. When the throttle opens, the valve 46 will quickly close and the rapidly spinning compressor 24 will immediately begin to supply large quantities of compressed air to the engine cylinder. As a result, the engine will experience a rapid pickup of power and speed, to produce good performance. The rapid spinning of the compressor 24 will also cause rapid spinning of the exhaust turbine 22. Thus, when the throttle opens after a gear change, the exhaust turbine 22 will be maintaining a low back pressure on the cylinder, for efficient high power operation of the engine, to increase the engine pickup and fuel efficiency.
The valve 46 includes a valve member 50 which is urged by a spring 52 against a valve seat 54. However, a sensing line 56 extending from the cylinder end 16C of the inlet conduit to a chamber 58 of a valve cylinder can press against a plunger 60 connected to the valve member 50 to lift the valve member off the seat and open the recirculating valve. Thus, when the pressure of compressed air at the cylinder end 16C of the inlet conduit increases to a high predetermined level, the valve member 50 is drawn back against the force of the spring 52, to open the recirculating passage. A high pressure occurs only when the engine is operating at high load, so that the engine generates considerable exhaust gases to rapidly turn the exhaust turbine and compressor but is not operating at a sufficiently high speed to draw in all of the compressed air produced by the exhaust turbine and compressor.
In addition to sensing the pressure of air near the cylinder, the valve 46 is constructed to sense the inflow of air into the entrance end 16E of the inlet conduit 16. This is accomplished by the use of a venturi 30 between the entrance end 16E of the inlet conduit and the discharge end 44 of the recirculating passage. An inflow sensing line 62 extends from the throat of the venturi 30 to a chamber 64 that lies on a side of the plunger 60 opposite the chamber 58. The pressure in the chamber 64 decreases as the volume flow of air into the inlet conduit increases, so that the plunger 16 is drawn further into the chamber 64 to move the valve member 50 open. The use of the inflow sensing line 62 is useful to open the recirculating valve and thereby reduce the pressure at the cylinder end 16C of the inlet conduit when the engine is operating at high speed. When the engine operates at high speed, it can draw in the air at 16C to minimize the pressure thereat so that the valve 46 might otherwise remain closed. The combination of a high load at high speed can be especially injurious to the engine because of the difficulty of removing heat sufficiently fast, and therefore it is desirable to open the recirculating valve at a somewhat lower pressure at high engine speed than at lower speed.
In one system, the compressor turbine 24 will supply an air pressure at 16C of about 4 psi at moderate engine speeds and loads. The sensing line 56 which senses the air pressure supplied to the cylinder, will open the recirculating valve at low engine speeds, typically about 5 psi above atmospheric pressure. At high engine speeds, the effect of the inflow sensing line 62 will result in the valve opening at a manifold air pressure at 16C, of perhaps 3 psi. It may be noted that an intercooler 70 is sometimes used, to cool the compressed air where high compression is employed that overheat the engine. The intercooler will somewhat increase the manifold air density at 16C, which can be offset by resetting the initial pressure applied by the recirculating valve spring 52. This can be accomplished by turning a knob 72 to increase the preloading of the spring.
In summary, the maximum boost or charge pressure can be set for moderate engine loads and speeds by the preload on the spring 52. The sensing line 56 references the valve to the air pressure supplied to the engine, while the inflow sensing line 62 lowers the maximum boost pressure as engine speed increases. The degree of control is directly affected by the area of the venturi 30.
The recirculating valve can be constructed as shown for valve 80 of FIGS. 2 and 3, wherein the plunger or valve member 82 slides across the recirculating passage 40a and therefore the pressure in the recirculating passage does not tend to open the valve. The sensing line 56 which senses the boost pressure at the engine, the inflow sensing line 62 which senses the rate of air flow, and the spring preload setting knob 72 all operate in substantially the same manner, as for the valve 46, to progressively open the recirculating passage as the air pressure at the engine inlet and the flow rate of air into the inlet passage increase. A plug can be substituted for the knob 72, to prevent inexperienced persons from setting the spring preload so that the engine will overheat.
The system of FIG. 1 can be modified to provide better response during cruising of a vehicle when it is travelling rapidly but the driver is depressing the accelerator pedal very little or not at all. In that circumstance, the engine may generate a high vacuum such as 20 inches of water at the location 16C. The path of air flow from 16E to the engine can be shortened by opening the valve 46 to allow incoming air to flow from point 44, through the valve 46, and to the engine intake at 16C, without passing through the compressor 24. This can shorten the air path by a considerable distance such as 2 to 3 feet, to enable better response when the driver wants to accelerate. The system of FIG. 1 can be modified to accomplish this, by connecting a check valve between the two sensing lines 56 and 62 to permit air flow from line 62 to line 56, so as to permit a vacuum at 56 to be applied to the chamber 64 to open the valve. Another check valve may be installed along the line 56 adjacent the chamber 58, to prevent such a vacuum from being applied to the chamber 58.
Thus, the invention provides a turbo-charged engine which has good response during acceleration, and which has generally high efficiency. This is accomplished by the use of a recirculating passage connected to positions along the air inlet conduit located up-path and downpath from the air compressor, and by providing a valve for controlling the recirculation of air therethrough. The valve can be controlled to open and permit recirculation of air when the pressure at the air intake manifold reaches a high level that would tend to produce excessive pressure and temperature in the cylinder. Furthermore, the valve can be made responsive to the volume flow of air towards the cylinders, to reduce the manifold air pressure at which the valve opens as the engine speed increases.
Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art, and consequently it is intended that the claims be interpreted to cover such modifications and equivalents.
|
An improvement in a turbocharged engine of the type that includes an exhaust turbine driven by exhaust gases from the cylinders of the engine, and which drives a compressor located along an inlet conduit leading to the engine to supply compressed air to the cylinder. The improved system includes a recirculating passage which can carry compressed air from a point along the inlet conduit downstream of the compressor, back to a point along the inlet conduit which is upstream from the compressor turbine, to recirculate the air. A valve located along the recirculating passage, is operated by sensors detecting when the engine is operated at high loads, to then open the valves to cause recirculation of the air pumped by the compressor. The recirculation not only reduces the air pressure supplied to the cylinder to avoid overcharging of the engine, but also causes the two turbines to spin faster to minimize exhaust back pressure for greater engine efficiency and to enable the turbocharger impeller to pick up speed faster after a gear change.
| 5
|
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT
[0003] Not applicable.
REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC
[0004] Not applicable.
BACKGROUND OF THE INVENTION
[0005] 1. Field of the Invention
[0006] The present invention relates to new complexes for co-ordinating a transition metal, in particular lanthanides, and their applications in the medical field.
[0007] 2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
[0008] The unique electronic properties of the lanthanide ions, such as their long life luminescence and their well-defined emission spectrum, turn these compounds into an ideal tool for usage in the medical field.
[0009] Indeed, the use of the lanthanide complexes, enables to distinguish the fluorescence considered as a background noise and the signal targeted. Thus said complexes are often used, in the design of detectors, as spectroscopic and luminescent probes for solving structural and analytical problems and as fluorescence imaging systems.
[0010] According to the rules laid down by the “International Union of Pure and Applied Chemistry” (IUPAC), by lanthanide is meant the series of the chemical elements ranging from Cerium (Z=58) to Lutecium (Z=71). By including Lanthane (Z=57), these elements are called lanthonoid. The expression “rare earth” applies to the lanthanoid together with Scandium (Z=21) and Yttrium (Z=39), the latter having similar chemical properties. In practice, the designations as lanthanides, lanthanoid and rare earth are used for describing these elements.
[0011] Generally, the lanthanides form their most stable compounds when they are in +3 oxidation state. The electronic structure of the Ln III ions is that of the xenon for the La III and then corresponds to the filling of the orbitales 4f14 up to [Xe]4f 14 for the Lu III .
[0012] Currently, most studies performed with lanthanide complexes have been oriented towards establishing light-emitting probes including long life visible light transmitters, in particular Eu III and Tb III , or transmitters in the near-infrared spectrum, such as the Pr III , Er III Yb III or the Nd III .
[0013] However, as the prohibited transition 4f-4f, so-called Laporte prohibition, prevents the direct excitation of the lanthanides, the latter must be performed using certain adequate organic chromophores.
[0014] In the meaning of the invention a “chromophore” is a molecule capable of absorbing the UV/visible light and of transferring to the metallic centre, which, by accepting such energy, becomes “excited” to a state capable of transmitting light (aerial effect). Preferably a “chromophore”, also called “aerial”, corresponds to an atom moiety liable to partake of long enough a sequence with double links matched in an organic molecule. An aromatic cycle carrying delocalisable π electrons will be considered as a chromophore in the sense of the present invention.
[0015] Besides, for practical reasons in physiological conditions, the lanthanide ions must be incorporated in highly stable complexes. Indeed, the efficiency of the energy transfer from the ligand on the lanthanide is decisive for the design of highly performing probes.
[0016] Moreover, so as to obtain high quantal throughput, non-radiative de-energisation should be prevented, or at least minimised, of the excited state of the lanthanide ion further to an interaction of the metal with the surrounding water molecules.
[0017] The incorporation of the chromophores in certain polydentate ligands studied to that end leads to greater stability of the lanthanide chelates in solution, enabling greater protection of the metal from the water molecules.
[0018] However, the tendency of the lanthanide ions to adopt a high co-ordination number and their lack of stereochemical selectivity turn the design of these ligands into a major challenge.
[0019] A strategy, which has been adopted by different research groups, is based upon a “tripod” structure of a ligand in order to organise three trivalent binding units in ennea-coordinated Ln III complexes.
[0020] This approach has led, in some cases, to an efficient protection of the metal from the surrounding water molecules, but synthesis difficulties make it little interesting.
[0021] The preparation of the polydentate ligands, enabling the arrangement of four bidentate moieties around a lanthanide ion, has less drawn the attention of the researchers in spite of the excellent luminescence of observed for tetra complex obtained from bidentate chromophore ligands, such as quinolinates or tropolonates.
[0022] Recently, octadentate ligands including four divalent chromophores have led to lanthanide complexes with energy emissions in the ultra-violet zone (UV) or in the near-infrared spectrum (NIR) which are very efficient.
[0023] However, the structure of these complexes has not been elucidated as yet, and the fact that the part of the structure of the ligand binding the bidentate units together is highly flexible, involves that the protection of the central metal is far from optimum.
BRIEF SUMMARY OF THE INVENTION
[0024] The aim of the present invention is to provide new complexes for co-ordinating a transition metal, in particular lanthanides, which remedy the shortcomings aforementioned, particularly as regards their stability in aqueous medium and their flexibility.
[0025] Another aim of the present invention is to provide new complexes for co-ordinating a transition metal, in particular lanthanides, which are easy to prepare and which exhibit high luminescence quantal throughput.
[0026] Another aim of the present invention is to provide new co-ordinating complexes exhibiting chemical and photophysical features liable to be used in the medical and biotechnological field.
[0027] Other aims and advantages of the invention will appear in the following description solely given by way of example and without being limited thereto.
[0028] The present invention relates to a complex for co-ordinating a transition metal of the general formula (I)
[0000] {[M(L)]X(H 2 O) n } p wherein: M represents an element belonging to the group of the lanthanides, L represents a decadentate chromophore ligand of the general formula (II):
[0000]
Wherein,
[0000]
R 1 , R 2 , R 3 and R 4 correspond independently to hydrogen, an alkyl or aryl radical,
A 1 , A 2 , A 3 and A 4 correspond independently to a structure of the general formula (III):
[0000]
Wherein,
[0000]
U 1 , U 2 and U 3 correspond independently to a C or an N,
R 5 , R 6 and R 7 correspond independently to hydrogen, an alkyl or aryl radical,
Y corresponds to a C, O, S, P or N,
m is an integer corresponding to the number of free valencies of Y,
R 8 corresponds independently to hydrogen, an alkyl or aryl radical,
X represents a counter-ion, n represents the number of molecules of hydration water, p corresponds to the number of monomers, H 2 O represents the molecules of hydration water.
[0042] An alkyl radical may be optionally mono- or polysubstituted, linear, branched or cyclic, saturated or unsaturated, in C1-C20, preferably in C1-C10, wherein the substituent(s) are liable to contain one or several heteroatoms such as N, O, F, CI, P, Si or S. Among such alkyl radicals, the methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl and pentyl radicals may also be mentioned. Among the unsaturated alkyl radicals the ethenyls, propenyls, isopropenyls, butenyls, isobutenyls, tert-butenyls, pentenyls and acetylenyls may also be quoted.
[0043] An aryl radical may be an aromatic or heteroaromatic carbonous structure, mono- or polysubstituted, formed of one or several aromatic or heteroaromatic cycles each comprising from 3 to 8 atoms, wherein the heteroatom may be N, O, P or S.
[0044] Optionally, when the alkyl or aryl radicals are polysubstituted, the substituents may be different from one another. Among the substituents of the alkyl and aryl radicals, one may in particular mention the halogen atoms, the alkyl, haloalkyl, aryl substituted or not, heteroaryle substituted or not, amino, cyano, azido, hydroxy, mercapto, ceto, carboxy, etheroxy and alcoxy such as methoxy groups.
[0045] The present invention also relates to a preparation method of a ligand as described above, characterised in that it includes the reaction of a diamine of the general formula (IV):
[0000]
Wherein,
R 1 , R 2 , R 3 and R 4 are as defined above,
and of at least one compound of the general formula (V)
[0000]
Wherein,
[0000]
Y, R 5 , R 6 , R 7 , R 8 , U 1 , U 2 and U 3 are as defined above,
R corresponds to an alkyl or an aryl,
LG represents an outgoing group liable to undergo a nucleophilic substitution from the diamine.
[0052] The present invention relates moreover to a preparation method of co-ordinating complexes characterised in that it comprises the reaction between a lanthanide salt and a ligand in aqueous medium, as well their usage in the medical field, such as in diagnostic imaging, radiotherapy, and in the design of neutron detectors, screens for X-rays, of the probes for imaging and bio-assays, diodes, optical fibres etc.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0053] The invention will be understood better when reading the following description, accompanied by the appended drawings.
[0054] FIG. 1 is a graph illustration of titration curves.
[0055] FIG. 2 is a schematic view of an illustration of the molecular structure of a lanthanide complex.
[0056] FIG. 3 is a schematic view of an illustration of the molecular structure of a second lanthanide complex.
[0057] FIG. 4 is a graph illustration of the 1 H RMN spectrum of a lanthanide complex.
[0058] FIG. 5 is a graph illustration of the 1 H RMN spectrum of a lanthanide complex at 333K.
[0059] FIG. 6 is a graph illustration of the 1 H RMN spectrum of a lanthanide complex at 298K.
[0060] FIG. 7 is a graph illustration of the emission spectrum of two lanthanide complexes after excitation at 274 nm.
[0061] FIG. 8 is a graph illustration of the emission and excitation spectra of a lanthanide.
DETAILED DESCRIPTION OF THE INVENTION
[0062] The present invention relates first of all to a complex for co-ordinating a transition metal of the general formula (I):
[0000] {[M(L)]X(H 2 O) n}p wherein:
M represents an element belonging to the group of the lanthanides, L represents a decadentate chromophore ligand of the general formula (II):
[0000]
Wherein,
R 1 , R 2 , R 3 and R 4 correspond independently to hydrogen, an alkyl or aryl radical,
A 1 , A 2 , A 3 and A 4 correspond independently to a structure of the general formula (III):
[0000]
Wherein,
[0000]
U 1 , U 2 and U 3 correspond independently to a C or an N,
R 5 , R 6 and R 7 correspond independently to hydrogen, an alkyl or aryl radical,
Y corresponds to a C, O, S, P or N,
m is an integer corresponding to the number of free valencies of Y,
R 8 corresponds independently to hydrogen, an alkyl or aryl radical,
X represents a counter-ion, n represents the number of molecules of hydration water, p corresponds to the number of monomers, H 2 O represents the molecules of hydration water.
[0078] According to the physical state adopted (crystallised or dissolved for instance), the complex may include so-called co-ordinating solvent molecules, it is in particular water molecules.
[0079] According to a particular embodiment of the present invention, the element belonging to the group of the lanthanides is Europium (Eu), or Cerium (Ce) or Terbium (Tb).
[0080] Advantageously R 1 , R 2 , R 3 and R 4 will be independently hydrogen, methyl or ethyl, preferably they will all be hydrogen.
[0081] The inventors consider that it is preferable that A 1 , A 2 , A 3 and A 4 are identical, since this enables to keep the symmetry of the molecule, thereby increasing the aerial effect and preventing the spurious energy transfers.
[0082] It is also preferable that Y is sulphur or oxygen, and in such a case m is equal to 0.
[0083] Generally speaking it is preferable to choose carbonous aromatic groups, the inventors consider that it is advantageous that U 1 , U 2 and U 3 are carbons.
[0084] The preferred complexes according to the invention are those for which R 5 , R 6 and R 7 are independently hydrogen or an alkyl radical, such as methyl or ethyl, advantageously they are identical and preferably correspond to hydrogens.
[0085] One of the advantages of such type of co-ordinating complex lies in their stability in aqueous medium which enables their usage in physiological and biological media and, hence, in the medical field.
[0086] Calcium, metal known by its significance in certain biological systems, is less complexed than the lanthanides by the ligand of the present invention. This selectivity is very significant for medical application.
[0087] In a particular embodiment of the present invention said ligand comprises four bidentate chromophores connected by an ethylenediamine skeleton.
[0088] According to a particular embodiment of the present invention, said ligand comprises four pyridinecarboxylate moieties bound by an ethylenediamine skeleton.
[0089] According to a particular embodiment of the present invention, the ligand including the four pyridinecarboxylate moieties is N,N,N′,N′-tetrakis[(6-carboxypyridine-2-yl)methyl]-ethylenediamine.
[0090] One of the advantages of the ligands according to the invention and particularly those of type N,N,N′,N′-tetrakis[(6-carboxypyridine-2-yl)methyl]-ethylenediamine, lies in that they include ten electron donor atoms and a “skeleton” formed of an ethylene diamine bridge perfectly adapted to the complexing of a lanthanide, in particular Eu, Tb and Ce, but also the lanthanides with emission in the infrared, providing highly effective protection of the central metal with respect to the surrounding water molecules, in particular water molecules of the solvent. Because of the protection, the complexes, in particular of Eu III and Tb III with the ligand N,N,N′,N′-tetrakis[(6-carboxypyridine-2-yl)methyl]-ethylene diamine, exhibit long life water luminescence, associated with high solubility and high stability.
[0091] According to the present invention, the counter-ion X present in the complexes is an element belonging to the group 1A of the periodic table of the elements, and more particularly potassium. The way the counter-ion K+ is bound to the complexes of Europium and of Cerium, leads to two different structures, a monomeric structure in the case of the complex with Europium and a dimeric structure in the case of the complex with Cerium.
[0092] The value of p varies according to the type of complex and represents the number of monomers each forming complexes, p is equal to one for a monomeric complex as it is the case for Europium and p is equal to 2 for a dimeric complex as it is the case for Cerium (see the examples of embodiment).
[0093] Similarly the value of n is function of the complex considered and of the atmosphere and temperature conditions. Typically this number will be ranging between 0 and 20 for a non-dissolved complex.
[0094] The invention also relates to The preparation of a decadentate chromophore ligand as described above, by reaction of a diamine of the general formula (IV):
[0000]
Wherein,
[0000]
R 1 , R 2 , R 3 and R 4 are as defined above,
and of at least one compound of the general formula (V)
[0000]
Wherein,
[0000]
Y, R 5 , R 6 , R 7 , R 8 , U 1 , U 2 and U 3 are as defined above,
R corresponds to an alkyl or an aryl.
LG represents an outgoing group liable to undergo a nucleophilic substitution from the diamine.
[0100] Advantageously the man of the art will select LG among most labile outgoing groups and in particular those reacting with amines. The inventors consider that Cl, Br, I, -OTf, -OTs, CN may be used advantageously.
[0101] The moiety R will be preferably selected among the methyl, ethyl, propyl, isopropyl, butyl, isobutyl, benzyl radicals and among the heteroalkyls in particular the radicals used as protective groups of the alcohol functions like the trimethylsiyl (TMS) or terbutyledimethylesilyl (TBDMS).
[0102] The method according to the invention may be provided in any suitable solvent, in particular organic solvents such as acetonitrile, tetrahydrofuran, chloroform, dichloromethane, carbon tetrachloride, toluene.
[0103] The preferred operating conditions are easily determined by the man of the art from the substituents that he will have chosen for its compounds, wherein the substitution reaction by an amine is well-known in the art. It is preferable to conduct the reaction in the presence of a base to facilitate the reaction of the amine, then to acidify the reactive medium for regenerating the alcohol protected by the group R.
[0104] Thus, according to the method, by reaction between ethyl ester of the 6-chloromethylpyridine-2-carboxylate and ethylenediamine, preferably in organic medium, the decadentate ligand N,N,N′,N′-tetrakis[(6-carboxypyridine-2-yle)methyl]-ethylene diamine, also designated in the present invention by H 4 tpaen, is easily obtained in five steps with a final throughput of 26.0%.
[0105] Schematically, the reaction may be described as follows:
[0000]
[0106] The preparation of the ligand H 4 tpaen is simple, may be used at large scale and may be easily modified for anchoring the complex with certain functional moieties capable of binding to biomolecules in order to develop markers for luminescence imaging.
[0107] The ligand N,N,N′,N′-tetrakis [(6-carboxypyridine-2-yl)methyl]-ethylene diamine may be prepared as follows.
[0108] Under an argon atmosphere, freshly distilled ethylenediamine (250 mL, 3.6 mmol) and anhydrous K 2 CO 3 (2.04 g, 14.8 mmol) are successively added to an ethyl ester solution of the 6-chloromethylpyridine-2-carboxylate (2.95 g, 14.8 mmol) in anhydrous acetonitrile (50 mL). After filtration and evaporation of the solvent a yellow oil is obtained.
[0109] After re-integration in dichloromethane the solution formed is washed twice with water (100 mL) and dried on anhydrous Na 2 SO 4 . After evaporation of the solvent, the yellow oil obtained is used without any other purification.
[0110] For regenerating the acid function, the raw product (2.56 g) dissolved in an aqueous solution of HCl 6M (40 mL) is raised to reflux overnight. After evaporation of the solvent up to 5 mL, the solution is cooled down to 5° C. overnight. The precipitate is collected by filtration, washed with a solution of HCI M then vacuum dried. 1.37 g H4tpaen.6HCI.5H 2 O are thus obtained with a 42% throughput.
[0111] The elementary analysis of the H4tpaen.6HCI.5H 2 O is as follows: MM=909.33, C 30 H 44 N 6 O 13 CI 6 : C, 39.42; H 4.88; N 9.24; found C, 39.49; H 4.90; N 9.24.
[0112] The RMN spectra of the H 4 tpaen are as follows:
[0113] 1 H RMN (D 2 0, 400 MHz, 298 K, pH=5): δ 3.57 (s, 4H, NCH 2 CH 2 N), 4.36 (s, 8H, NCH 2 py), 7.48 (d, 4H, CH), 7.77 (d, 4H, CH), 7.84 (t, 4H, CH),
[0114] 13 C RMN (D 2 O, 100 MHz): δ=51.6 (CH 2 ); 56.4 (CH 2 ); 57.8 (CH 2 ); 125.8 (CHpy); 128.4 (CHpy); 142.9 (CHpy); 147.4 (Cpy); 152.0 (Cpy); 166.4 (COOH); 172.1 (COOH).
[0115] The present invention relates moreover to a preparation method of a co-ordinating complex by reaction of a lanthanide salt with a ligand in aqueous medium.
[0116] Advantageously, the salt of a lanthanide is lanthanide chloride.
[0117] The ligand will be advantageously as described above.
[0118] In a particular embodiment of the present invention the lanthanide is Europium (Eu), Cerium (Ce) or Terbium (Tb), advantageously the lanthanide will be selected among the lanthanides with emission in the infrared.
[0119] The water soluble complexes, obtained from the ligand N,N,N′,N′-tetrakis[(6-carboxypyridine-2-yl)methyl]-ethylene diamine, are isolated with a throughput ranging between 50 and 60% after reaction of said ligand with a hexa hydrated lanthanide chloride, in particular with Cerium or Europium and after adjustment of the pH to 6.
[0120] By way of example, not limited thereto, the Europium and Cerium complexes may be prepared by reaction between Europium trichloride or cerium trichloride and the ligand N,N,N,N′,N′-tetrakis[(6-carboxypyridine-2-yl)methyl]-ethylene diamine.
[0121] These complexes may be prepared as follows.
[0122] A solution of CeCI 3 7H 2 O or of EuCI 3 .6H 2 O (0.138 mmol) in water (0.5 mL) is added to a solution of N,N,N′,N′-tetrakis[(6-carboxypyridine-2-yl)methyl]-ethylene diamine (0.138 mmol) at a pH of 5, adjusted by the addition of KOH (0.2 M) in water (6 mL). The solution thus obtained is stirred at room temperature for 2 hours and the pH is adjusted to 6 par the further addition of KOH (0.2 M).
[0123] After evaporation of water, the solid obtained is picked up in EtOH (5 mL) and the solution is filtered to eliminate insoluble salts. The solvent is evaporated and the residue picked up in water.
[0124] Slow evaporation over 5 days of the aqueous solution (1 mL) of the solid enables to obtain the complex ([Eu(tpaen)]K) in the form of a white solid and the complex ([Ce(tpaen)]K in the form of a yellow solid with a throughput ranging between 50 and 60%.
[0125] The chemical and physical features of these complexes are as follows:
[0126] [Eu(tpaen)]: 1 H RMN (D 2 O, 400 MHz, 298 K, pD=6.9): δ−2.07 (s br, 2H, H 6 /H 6 ,), −1.11 (s br, 2H, H 4 ′), −0.99 (s br, 2H, H 4 ), 3.48 (s br, 2H, H 5 ), 4.28 (s br, 2H, H 5 ′), 4.41 (d br, 2H, H 3 ), 5.43 (d br, 2H, H 3 ), 5.65 (s br, 2H, H 1 ), 5.79 (s br, 2H, H 1 ), 5.96 (br, 2H, H 2 ′), 6.53 (br, 2H, H 2 ), 8.40 (br, 2H, H6/H 6 ′).
[0127] [Ce(tpaen)]: 1 H RMN (D 2 O, 400 MHz, 298 K, pD=5.4): δ−2.03 (s br, 2H, H6/H6′), 0.09 (s br, 2H, H 5 ′), 1.18 (s br, 2H, H 6 /H 6′ ), 3.25 (d, 2H, H 4 ), 3.51 (d, 2H, H 4 ), 5.44 (s br, 2H, H 5 ), 7.97 (d, 2H, H 3 ), 8.10 (d, 2H, H 3′ ), 8.45 (d, 2H, H 1 ), 8.91 (t, 2H, H 2 ), 8.94 (d, 2H, H 1 ), 9.04 (t, 2H, H 2 ′).
[0128] The crystallographic data for Eu(tpaen)] K(H 2 O) 3 . 4H 2 O: C30H38Eu KN6O15, M=913.7, Monoclinical, spatial group P2 (1)/n, a=11.995(2) b=14.539(3), c=21.407(5) Å, β=106.186(3) V=3585.2(12) Å 3 , Z=4, p c =1.693 g cm− 3 , μ=1.944 mm− 1 , T=298 K. From the 12504 reflections collected, 5133 were unique (R int =0.0192). The treatment of the data has converged to R 1 =0.0296, wR2=0.0667. Max/min of residual density 0.693 and −0.528 eÅ− 3 .
[0129] The crystallographic data for {[Ce(tpaen)] K(H 2 O) 3 } 2 . 16H 2 O, C30H46 CeKN6O19, M=973.95, Monoclinical, spatial group P2(1)/c, a=11.7615(10) b=14.5931(12), c=22.965(2) Å, β=101.640(1) V=3860.7(6) Å 3 , Z=4, p c =1.676 g cm −3 , μ=1.374 mm− 1 ,T=193 K. From the 12929 reflections collected, 7459 were unique (R int =0.0310). The treatment of the data has converged to R 1 =0.0430, wR2=0.1340. Max/min of residual density 1.055 and −2.462 eÅ−3.
[0130] Besides, five de-protonation constants [pK a1 =2.8 (1), pK a2 2=3.2 (1), pK a3 =3.9 (2), pK a4 =5.1 (1) and pK a5 =7.8 (1)] may be determined for the ligand H 6 tpaen by potentiometric titration as well the stability constants of the corresponding complexes of Eu III and of Ca II [log β EuL =15.3(3) for the complex of Eu III and log β CaL =8.5 (5)]. FIG. 1 shows the titration curves for the ligand H 6 tpaen (▴), for the complex Eutpaen (⋄) and for the complex Catpaen (▪).
[0131] The values of pEu=15.7, pGd=15.0 and pCa=8.5 {−log [M]| free at a pH of 7.4, [M] total =1 μM, and [tpaa] total =10 μM), when they are compared with the value of pEu=14.0 for tetra acetic diamine ethylene acid (EDTA) show that the ligand tpaen forms lanthanide complexes with sufficient stability for their in vivo usage and also show good selectivity regarding Europium with respect to calcium.
[0132] For potentiometric titration, the solutions of the complex of Eu(III) may be prepared by dissolution of a determined amount of EuCI 3 .6H 2 O in water. The de-protonation constants of H 6 tpaen are given by Kai=[H6-iL] 2-1 /[H 5 −iL] 1-i [H] + , and as already mentioned previously, the values obtained are pK a1 =2.8(1), pK a2 =3.2(1), pK a3 =3.9(2), pK a4 4=5.1(1) and pK a5 =7.8(1).
[0133] The exact concentration of the ion Eu 3+ could be determined by colorimetric titration in an acetate buffer (pH=4.5), using as a reference a solution of H 2 Na 2 edta and orange xylenol as an indicator.
[0134] The solutions of Ca(II) could be prepared by dissolution of CaCI 2 in water. The exact concentration of the ion Ca 2+ can be determined by colorimetric titration at a pH 12.5 using as a reference a solution of H 2 Na 2 edta and calgonite as an indicator. 20 mL of a solution of H 4 tpaen (3,10− 4 M), acidified (pH˜2.5) 1:1 Ln:mixture of ligands ([L] 3.10− 4 M), acidified (pH˜2.5) 1:1 Ca:mixture of ligands ([L] 7.10− 5 M) are titrated in a cell with a thermostat (25.0° C.+/−0.1° C.) under Argon after addition of a solution of KOH 0.1 M.
[0135] The ionic load was determined with KCl (μ=00.1 M). The titrations have been conducted with a Metrohm 751 GPD Titrino potentiometer fitted with a glass pH electrode. The electrode system was calibrated before each measurement.
[0136] The electromotive load is given by the equation E=E°+sp[H + ] wherein E° and s are determined by titration of a known amount de HCl with 0.1 M KOH at μ=0.1 M (KCl), using the zone of the acid for the titration. The value used for the ionic product of water was pKw=13.77. More than 50 data points have been collected for each experiment.
[0137] Moreover, as shown on FIGS. 2 and 3 , the crystalline structure respectively of the complexes [Eu(tpaen)]K(H 2 O) 3 .4H 2 O, and {[Ce(tpaen)]K(H 2 O) 3 } 2 . 16H 2 O is analysed X-ray diffraction. In both complexes, the ion Ln III s deca-coordinated by the four oxygen atoms (the average value for the distances Metal-0 is 2.42 (1) A for Europium and 2.50 (4) A for Cerium) and by the six nitrogen atoms (the average value for the distances metal-N-pyridine is 2.65 (4) A for Europium and 2.72 (1) Å for Cerium and the average value for the distances metal-N-amine is 2.91 (1) Å for Europium and 2.91 (4) Å for Cerium.
[0138] The number of co-ordinated water molecules present in solution, q, was determined from life time measurements using the Parker equation (q=A Ln (1/τH 2 O−1/τD 2 O−β Ln ) wherein A Tb =5 ms, A EU =1.2 ms, αTb=0.06 ms− 1 and α Eu =0.25 ms− 1 ). The quantal throughput Q was calculated using the equation Q x /Q r =A r (v).n x 2 .D x /A x (v)n r 2 .D r wherein x is the sample, r the reference; A the absorbance, v the number of excitation waves used, n the refractive index, and D the integral of the intensity transmitted.
[0139] The complexes of tris(dipicolinate) [Eu(dpa) 3 3− ] (Φ=13.5%, 7.5×10− 5 M in buffer Tris 0.1 M) and [Tb(dpa) 3 ] 3− (Φ=26.5%, 6.5×10 −5 M in buffer Tris 0.1 M) are used as references respectively for the determination of the quantal throughputs of the samples of Eu- and Tb. The consistency of the data was checked by measuring the quantal throughput of the complexes of the tris(dipicolinate) relative to rhodamine 101 (Q abs =100% ethanol) and cresyl violet (Q abs =54% methanol).
[0140] The chemical and physical analyses of the complexes according to the present invention, show that the “arms” of the pyridine carboxylate moiety of the ligand N,N,N′,N′-tetrakis[(6-carboxypyridine-2-yl)methyl]-ethylene diamine surround the central metal in a pseudo symmetrical Ce and helicoid arrangement.
[0141] Both complexes crystallise into a racemic mixture of enantiomers Λ and Δ.
[0142] The spectra of nuclear magnetic resonance (RMN) of the Europium and Cerium complexes, as shown on FIG. 4 for the case of the Europium complex with the ligand tpaen at 298 K, show that their structure is compatible with a rigid symmetry C2 wherein the four “arms” of the ligand remain co-ordinated with the metal during the time taken for obtaining the RMN spectrum (*EtoH).
[0143] The symmetry observed matches a double-helix chiral structure in solution, similar to that encountered in solid state.
[0144] The complexes keep their rigid structure in a temperature range between 298-363K, as shown by the 1 H RMN of FIGS. 5 (* DSS; # impurity) and 6 (* free ligand), performed respectively at a temperature of 333 and de 298 K for the particular case of the complex [Ce(tpaen)]-in D 2 O.
[0145] The presence of a rigid symmetry C2 similar to that described above was also observed for the same temperature range for the complex of La and Tb prepared in situ in deuterized water to a pH of 7.7. The high stiffness of these complex in solution, very rarely observed for the lanthanide complexes with a high denticity ligand, suggest that the arrangement of the ten donor atoms provided by the simple ethylene diamine chain is well suited to the formation of lanthanide complexes conferring high and efficient protection to the central metal regarding the molecules of the solvents.
[0146] As results of this protection, the complex d Eu III and of Tb III with the ligand tpaen exhibit a high luminescence with a long life in water and in deuterized water. The life times of the levels Eu(5Do) and Tb( 5 D 4 ) for [Eu(tpaen)]″ and [Tb(tpaen)]″ match the presence of 0.04±0.2 and 0.03±0.2 water molecules co-ordinated respectively in the complexes Eu and Tb.
[0147] The luminescent properties of the lanthanide ions, in particular Eu and Tb, are hence largely improved by the ligand tpaen. FIG. 7 shows the emission spectrum of [Eu(tpaen)] (full line) and [Tb(tpaen)] (dotted line) after excitation of the ligand at 274 nm.
[0148] An efficient energy transfer from the ligand to the metal is put forward by the resemblance between the excitation and absorption spectra of the Europium and Terbium complexes. FIG. 8 shows the absorption spectrum (dotted line) and the excitation spectrum (full line) of the complex of [Tb(tpaen)] in a buffer solution of Tris.
[0149] The quantal throughput for the complex of [Tb(tpaen)] (Φ=45%) measured relative to the complex of [Tb(dpa) 3 ] 3− in an aerated buffer solution of Tris of concentration 0.1 M, with a 15% experimental error, is one of the highest values mentioned until now. The chromophore tpaen also sensitises efficiently the Europium ion whereof the value for the quantal throughput is 7%. This value, while smaller than that obtained for the complex of Tb III remains however higher than the quantal throughput of the lanthanide complexes used currently in marketed light-emitting probes.
[0150] As shown in the following table, the intense luminescence of these ions results from an efficient energy transfer from the ligand to the metal and from a protection of the central metal relative to non-radiative deactivation by the surrounding water molecules.
[0000]
compound
λexc(nm)
ε(M −1 cm −1 )
τ H2O (ms)
τ D2O (ms)
Φ H2O
tpaen
270
15800
Eu(tpaen)
274
21600
1.70(2)
3.30(1)
0.07
Tb(tpaen)
274
21632
3.0(1)
3.75(1)
0.45
[0151] The life time of the luminescence observed in the terbium complex in water, to the inventors' knowledge one of the longest observed until now, excludes the presence of a desexcitation process including the return of energy from the metal towards the ligand. This value for the life time is quite compatible with an energy level of the triplet state of the complex [Tb(tpaen)] similar to that divulged recently, (22988 cm −1 ,) for the complex of an octavalent ligand including two pyridine carboxylate moieties. The high quantal throughput for the terbium complex matches this value quite well.
[0152] The co-ordinating complexes according to the present invention exhibit several advantages. On the one hand, this direct approach to arrange four divalent chromophores in a decadentate ligand produces highly soluble lanthanide complexes which are stable at a physiological pH. On the other hand, the architecture of the ligand leads to a rigid structure wherein the central metal is protected effectively from the interactions with the molecules of the solvent.
[0153] Moreover, this approach opens a wide variety of perspectives for the development of the stable and luminescent probes in the zone of the ultraviolet-visible, infrared and near-infrared, using these compounds, prepared preferably from chromophores transmitting a luminescence in the zone of the ultraviolet or of the near-infrared for a usage in medical imaging and in bio-assays. More generally the medical field, particularly that of the medical analyses seems to be able to benefit from the invention. Besides, the compounds as described in the present application may be anchored with certain functional moieties capable of binding to biomolecules in order to develop markers for luminescence imaging. The complexes may incorporate recognition functions such as dendrimers or also be bound to peptides, oligonucleotides, polymers, nanotubes.
[0154] The invention thus also relates to a biomolecule anchored on a complex according to claim, in particular to serve as a luminescent probe. The complexes according to claim, because of their properties, may be used in the nanotechnological industry and in particular in nanotechnological devices such as diodes or optical fibres.
[0155] Naturally, other embodiments, understandable to the man of the art, could have been contemplated without departing from the framework of the invention.
|
The invention concerns a transition metal coordination complex of general formula (I) {[M(X)]C(H 2 O)n}p wherein: M represents an element belonging to the lanthanide group; and L represents a decadentate chromophore ligand of general formula (II). R1, R2, R3 and R4 independently represent hydrogen or an alkyl or aryl radical. A1, A2, A3 and A4 independently represent a structure of general formula (III). U1, U2 and U3 independently represent C or N, and R5, R6 and R7 independently represent hydrogen, an alkyl or aryl radical. Y represents C, O, S, P or N, and m is an integer representing free valences of Y. R8 represents independently hydrogen, an alkyl or aryl radical. X represents a counter-ion, and n represents hydrating water molecules. p represents monomers. H 2 O represents the hydrating water molecules. The invention also concerns a method for preparing such a ligand.
| 2
|
SUMMARY OF THE INVENTION
The present invention relates to new organic compounds and more particularly is concerned with novel monobactam (monocyclic β-lactam) compounds that possess antibacterial activity, which may be represented by the following structural formula: ##STR1## wherein R may be hydrogen or methyl and the pharmacologically acceptable salt cations thereof.
DETAILED DESCRIPTION OF THE INVENTION
Representative compounds of the present invention are appreciably soluble in solvents such as acetone, ethanol, toluene, methylene chloride and the like and are soluble in dilute aqueous sodium bicarbonate and may form a pharmacologically acceptable salt cation with an alkali metal such as sodium or potassium and the like.
The invention also relates to the synthesis of new compounds that possess antibacterial activity. More specifically, it relates to the synthesis of the novel monocyclic β-lactams as illustrated in Schemes 1 and 2.
Compound 12b in Scheme 1 and Compound 12a in Scheme 2 have been shown to exhibit antibacterial activity against various pathogenic bacteria in vitro. ##STR2##
In accordance with Scheme 1, the reaction of t-butyloxycarbonyl-L-serine (1a) with benzophenone hydrazone (2) in the presence of 2-ethoxy-1-(2H)-quinolinecarboxylic acid ethyl ester afforded the hydrazide derivative N-(t-butyloxycarbonyl)-L-serine-2-(diphenylmethylene)hydrazide (3a) which readily underwent ring-closure under Mitsunobo conditions using diethyl azodicarboxylate and triphenylphosphine to give the β-lactam t-butyl (S)-[1-[(diphenylmethylene)amino]-2-oxo-3-azetidinyl]-carbamate (4a) in good yield. Catalytic hydrogenation in a Parr apparatus produced the N-amino compound t-butyl (S)-1-amino-2-oxo-3-azetidinylcarbamate (5a). Reaction of compound (5a) with benzyl glyoxylate (6) afforded the imino derivative benzyl (S)-3-[t-butyloxycarbonylamino]-2-oxo-1-azetidinyliminoacetate (7a) which was converted to the amino derivative 3-(t-butoxycarbonylamino)-2-oxo-1-azetidinyliminoacetic acid (8a) by catalytic reduction in the presence of palladium on carbon at atmospheric pressure. Treatment of (8a) with trifluoroacetic acid afforded the aminoacid (S)-[(3-amino-2-oxo-1-azetidinyl)imino]acetic acid trifluoroacetate (9a). Condensation of the trimethylsilyl derivative (10a) with the activated ester of 2-(2-amino-4-thiazolyl)-2-methoxyiminoacetic acid (11) prepared from 1-hydroxybenzotriazole and N,N'-dicyclohexylcarbodiimide gave the desired monobactam derivative (S)-3-[[(2-amino-4-thiazolyl)(methoxyimino)acetyl]amino]-2-oxo-1-azetidinyliminoacetic acid 12a.
Also in accordance with Scheme 1 and starting with the reaction of t-butyloxycarbonyl-L-threonine (1b) with benzophenone hydrazone (2) in the presence of 2-ethoxy-1(2H)-quinolinecarboxylic acid ethyl ester the hydrazide derivative N-(t-butyloxycarbonyl)-L-threonine-2-(2-diphenylmethylene)hydrazide (3b) was obtained. Ring closure of (3b) as described above with diethyl azodicarboxylate and triphenylphosphine gave the β-lactam, t-butyl (S)-[1-[(diphenylmethylene)amino]-2-(S)-methyl-4-oxo-3-azetidinyl)-carbamate (4b). Catalytic hydrogenation of (4b) gave the N-amino compound t-butyl 1-amino-2-(S)-methyl-4-oxo-3-(S)-azetidinylcarbamate (5b) which was reacted with benzyl glyoxylate (6) to give the imino derivative benzyl [[4(S)-methyl-3(S)-[(t-butoxycarbonyl)amino]-2-oxo]imino]acetate (7b). Catalytic reduction of (7b) gave the amino derivative 4(S)-methyl-[[3(S)-[[(t-butyloxycarbonyl]amino]-2-oxo-1-azetidinyl]imino]acetic acid (8b) which was treated with trifluoroacetic acid to give the amino acid, [[(S)-3-amino-4-oxo-2-(S)-methyl-1-azetidinyl]iminoacetic acid trifluoroacetate (9b). Then condensation of the trimethylsilyl derivative (10b) with the activated ester of 2-(2-amino-4-thiazolyl)-2-methoxyiminoacetic acid (11) gave the desired monobactam derivative (S)-3-[2-(2-amino-4-thiazolyl)]-(Z)-2-methoxyiminoacetylamino-2-(S)-methyl-4-oxo-1-azetidinyliminoacetic acid (12b). ##STR3##
In accordance with Scheme 2, the reaction of t-butyl (S)-1-amino-2-oxo-3-azetidinylcarbamate (5a) with allyl glyoxylate (13) afforded the imino derivative allyl (S)-3-[t-butyloxycarbonylamino]-2-oxo-1-acetidinyliminoacetate (14a). Treatment of (14a) with trifluoroacetic acid afforded the aminoacid, allyl(S)-[(3-amino-2-oxo-1-azetidinyl)imino]acetate trifluoroacetate (15a). Condensation of the aminoacid (15a) with the activated ester of 2-(2-amino-4-thiazolyl)-2-methoxyiminoacetic acid (11), (prepared as hereinbefore described), in the presence of dicyclohexylcarbodiimide, 1-hydroxybenzotriazole and triethylamine gave the compound allyl (S)-3-[(2-amino-4-thiazolyl)-(Z)-2-methoxyiminoacetylamino]-2-oxo-1-azetidinyliminoacetate (16a). Then treatment of (16a) with tetrakis(triphenylphosphine)palladium (O), triphenylphosphine and potassium 2-ethylhexanoate gave the desired monobactam derivative potassium S-[[3-[[(2-amino-4-thiazolyl)-(Z)-(methoxyimino)acetyl]amino]-2-oxo-1-azetidinyl]imino]acetate (12a).
The in vitro antibacterial activity of representative monobactam derivatives of the present invention was determined against a spectrum of gram-negative bacteria by a standard agar dilution method. Mueller-Hinton agar containing two-fold decreasing concentrations of the compound was poured into Petri plates. The agar surfaces were inoculated with 1 to 5×10 4 colony forming units of bacteria by means of a Steers replicating device. The lowest concentration of the monobactam derivative that inhibited growth of a bacterial strain after 18 hours of incubation at 35° C. was recorded as the minimal inhibitory concentration (MIC) for that strain. The results are summarized in Table I.
TABLE I______________________________________In Vitro Antibacterial Activity of Potassium (S)--[[3-[[2-Amino-4-Thiazolyl-(Z)--(Methoxyimino)Acetyl]Amino]-2-Oxo-1-Azetidinyl]imino]acetate (12a) and (S)--3-[2-(2-Amino-4-Thiazolyl)]-(Z)--2-Methoxyiminoacetyl-amino-2-(S)--Methyl-4-Oxo-1-Azetidinyliminoacetic Acid (12b) MINIMAL INHIBITORY CONCENTRATION mcg/mlORGANISM (12a) (12b)______________________________________Escherichia coli MOR 84-20 8 2Escherichia coli VGH 84-19 8 2Escherichia coli CMC 84-50 4 2Escherichia coli ATCC 25922 8 8Klebsiella pneumoniae CMC 84-31 8 2Klebsiella pneumoniae MOR 84-24 16 8Klebsiella pneumoniae IO 83-5 8 4Enterobacter cloacae VGH 84-39 16 8Enterobacter cloacae K 84-10 8 4Enterobacter cloacae MOR 84-30 64 32Serratia marcescens MOR 84-41 32 4Serratia marcescens CMC 83-74 >128 16Serratia marcescens IO 83-63 32 8Morganella morganii VGH 84-12 64 4Morganella morganii CMC 84-38 32 8Morganella morganii MOR 84-45 128 16Proteus rettgeri IO 83-21 0.5 0.12Providencia stuartii CMC 83-3 32 2Citrobacter diversus K 82-24 16 4______________________________________
The compounds of the present invention have been found to be highly useful as antibacterial agents in mammals, when administered in amounts ranging from about one milligram to about 250 mg per kilogram of body weight per day. A preferred dosage regimen for optimum results would be from about 5 mg to about 100 mg per kilogram of body weight per day, and such dosage units are employed that a total of from about 0.35 g to about 7.0 grams of the active ingredient for a subject of about 70 kg of body weight are administered in a 24 hour period. This dosage regimen may be adjusted to provide the optimum therapeutic response. For example, several divided doses may be administered daily or the dose may be proportionally reduced as indicated by the exigencies of the therapeutic situation.
The active compounds of the present invention may be orally administered, for example, with an inert diluent or with an assimilable edible carrier, or they may be enclosed in hard or soft shell gelatin capsules, or they may be compressed into tablets, or they may be incorporated with excipients and used in the form of tablets, troches, capsules, elixiers, suspensions, syrups, wafers, and the like. Such compositions and preparations should contain at least 0.1% of active compound. The percentage of the compositions and preparations may, of course, be varied and may conveniently be between about 2% to about 60% of the weight of the unit. The amount of active ingredient in such therapeutically useful compositions is such that a suitable dosage will be obtained. Preferred compositions or preparations according to the present invention are prepared so that an oral dosage unit form contains between about 25 and 250 milligrams of active compound.
The tablets, troches, pills, capsules and the like may also contain the following: a binder such as gum tragacanth, acacia, corn starch or gelatin; excipients such as dicalcium phosphate; a disintegrating agent such as corn starch, potato starch, alginic acid and the like; a lubricant such as magnesium stearate; and a sweetening agent such as sucrose, lactose or saccharin may be added or a flavoring agent such as peppermint, oil of wintergreen, or cherry flavoring. When the dosage unit form is a capsule, it may contain, in addition to materials of the above type, a liquid carrier such as a fatty oil. Various other materials may be present as coatings or to otherwise modify the physical form of the dosage unit. For instance, tablets, pills, or capsules may be coated with shellac, sugar or both. A syrup or elixir may contain the active compound, sucrose as a sweetening agent, methyl and propylparabens as preservatives, a dye and flavoring such as cherry or orange flavor. Of course, any material used in preparing any dosage unit form should be pharmaceutically pure and substantially non-toxic in the amounts employed.
This invention will be described in greater detail in conjunction with the following examples.
EXAMPLE 1
N-(t-Butyloxycarbonyl)-L-serine-2-(diphenylmethylene)hydrazide; (3a)
A solution of 20.0 g (0.10 mole) of t-butyloxycarbonyl-L-serine, 19.6 g (0.10 mole) of benzophenone hydrazone, and 24.7 g of 2-ethoxy-1(2H)-quinolinecarboxylic acid ethyl ester in 250 ml of methylene chloride was stirred at room temperature for 16 hours. The solution was extracted with successive 100 ml portions of 1N hydrochloric acid, water, saturated sodium bicarbonate solution, water and brine, then dried over magnesium sulfate. The solvent was evaporated in vacuo and the resulting syrup was dissolved in ethyl acetate and crystallized by the addition of hexane to afford 24.5 g (64%) of product, mp 150.0°-152.5° C.
EXAMPLE 2
N-(t-Butyloxycarbonyl)-L-threonine-2-(2-diphenylmethylene)hydrazide; (3b)
The procedure of Example 1 was followed using N-(t-butoxycarbonyl)-L-serine to obtain the desired product, mp 123°-126° C.; IR (KBr) 1680 and 1715 cm -1 (--C═O).
EXAMPLE 3
t-Butyl (S)-[1-[(diphenylmethylene)amino]-2-oxo-3-azetidinyl]-carbamate; (4a)
A solution of 7.9 ml (0.05 mol) of diethyl azidodicarboxylate in 50 ml of tetrahydrofuran was added to a stirred solution of 9.6 g, (0.05 mol) of N-(t-butyloxycarbonyl)-L-serine-2-(diphenylmethylene)hydrazide and 9.6 g, (0.05 mol) of triphenylphosphine in 250 ml of tetrahydrofuran. The mixture was stirred and heated at 55° C. for 6 hours. The resulting solution was evaporated to dryness in vacuo. The residue was dissolved in 50 ml of ethyl acetate and chilled. The crystalline precipitate was removed by filtration and the filtrate was evaporated to dryness. The residue was chromatographed on silica gel using ethyl acetate-hexane (1:1) as the eluent to afford 12.0 g (66%) of the desired product; mp 167°-170° C.; IR (KBr) 1775 cm -1 (C═O); NMR (CDCL 3 ) δ1.38 (s, 9H, (CH 3 ) 3 C), 2.85 (dd, 1H, J=3 and 6 Hz, 4βH), 3.25 (t, 1H, J=6 and 6 Hz, 4αH), 4.70 (m, 1H, 3αH), 5.25 (d, 1H, NH), 7.40 (m, 10H, aromatic protons).
EXAMPLE 4
t-Butyl (S)-[1-[(diphenylmethylene)amino]-2-(S)-methyl-4-oxo-3-azetidinyl]-carbamate; (4b)
The procedure of Example 3 (Mitsunobo reaction) was followed using N-(t-butyloxycarbonyl)-L-threonine-2-(2-diphenylmethylene)hydrazide in place of N-(t-butyloxycarbonyl)-L-serine-2-(diphenylmethylene)hydrazide to give a white crystalline product (68%); IR (KBr) 1780 cm -1 ; NMR (CDCL 3 ) δ1.20 (d, 3H, CH 3 --), 1.45 (s, 9H, (CH 3 ) 3 C), 3.35 (m, 1H, 2βH), 4.20 (m, 1H, 3αH), 7.50 (m, 10H, aromatic protons).
EXAMPLE 5
t-Butyl (S)-1-amino-2-oxo-3-azetidinylcarbamate; (5a)
A 2.1 g amount of t-butyl(S)-[1-[(diphenylmethylene)amino]-2-oxo-3-azetidinyl]carbamate was dissolved in 100 ml of ethyl alcohol and 50 ml of ethyl acetate and 0.5 g of 10% palladium on carbon catalyst was added. The mixture was hydrogenated in a Parr apparatus at 30 psi for 24 hours. The mixture was then filtered through diatomaceous earth and evaporated to dryness in vacuo. The residue was crystallized from ethyl acetate to give 0.75 g of the product of the example, mp 165°-168° C.; IR (KBr), 1750 cm -1 ; NMR (d 6 DMSO) δ1.45 (s, 9H, (CH 3 ) 3 C), 3.25 (dd, 1H), 3.50 (t, 1H), 4.50 (m, 1H), 7.55 (d, 1H, NH).
EXAMPLE 6
t-Butyl-1-amino-2-(S)-methyl-4-oxo-3-(S)-azetidinylcarbamate; (5b)
The procedure of Example 5 was followed for this example using t-butyl(S)-[1-[(diphenylmethylene)amino]-2-(S)-methyl-4-oxo-3-azetidinyl]carbamate in place of t-butyl (s)-[1-[(diphenylmethylene)amino]-2-oxo-3-azetidinyl]carbamate to give the desired product in 72% yield: IR (KBr) 1750 cm -1 (β-lactam C═O); NMR (CDCL 3 ) δ1.40 (d, 3H, CH 3 ), 1.50 (S, 9H, (CH 3 ) 3 C), 3.40 (dd, 1H, 2βH), 5.35 (d, 1H, 3αH).
EXAMPLE 7
Benzyl (S)-3-[t-butyloxycarbonylamino]-2-oxo-1-azetidinyliminoacetate; (7a)
A solution of 2.33 g (11.57 mmol) of t-butyl (S)-1-amino-2-oxo-3-azetidinylcarbamate and 1.90 g (11.57 mmol) of benzyl glyoxylate in 250 ml of toluene was refluxed for one hour using a water separator. The solution was then evaporated to dryness in vacuo and the residue was dissolved in methylene chloride, filtered through hydrous magnesium silicate and again evaporated at reduced pressure. The resulting oil was triturated to a solid with ether which was collected by filtration and crystallized from acetone:hexane to give 2.12 g in 53% yield, mp 128°-130.5° C.; IR (KBr), 1780 cm -1 (β-lactam C═O); NMR (CDCL 3 ) δ1.45 (s, 9H), 3.50 (m, 1H), 3.80 (t, 1H), 5.25 (m, 1H), 5.30 (s, 2H), 7.38 (s, 5H).
EXAMPLE 8
Benzyl-[[4-(S)-methyl-3(S)-[(t-butyloxycarbonyl)amino]-2-oxo]imino]acetate; (7b)
A solution of 5.34 g (24.8 mmol) of t-butyl-1-amino-2(S)-methyl-4-oxo-3-(S)-azetidinylcarbamate and 4.07 g (24.8 mmol) of benzyl glyoxylate in 250 ml of toluene was treated as described in the procedure of Example 7 to provide 7.31 g of product. Recrystallization from acetone:hexane gave 6.60 g, (76% yield) of the desired product, mp 154.5°-158° C., IR (KBr) 1765 cm -1 (β-lactam C═O); NMR (DCCL 3 ); δ1.45 (s, 9H), 1.52 (d, 3H, J=8 Hz), 4.25 (m, 2H), 5.65 (s, 2H), 7.65 (s, 5H), 8.25 (s, 1H).
EXAMPLE 9
3-(t-Butyloxycarbonylamino)-2-oxo-1-azetidinyl-iminoacetic acid; (8a)
A solution of 1.0 g (2.88 mmol) of benzyl (S)-3-(t-butyloxycarbonylamino)-2-oxo-1-azetidinyliminoacetate in 20 ml of tetrahydrofuran was hydrogenated at atmospheric pressure for three hours in the presence of 200 mg of 5% palladium on carbon. The catalyst was removed by filtration and the solution was evaporated in vacuo to give a foam which was crystallized from ethyl acetate:hexane; to give 650 mg of the product of the example in 88% yield, mp 145°-147° C., IR (KBr); 1800 cm -1 (β-lactam, --C═O); NMR (d 6 DMSO); δ1.35 (s, 9H, t-butyl), 3.50 (m, 1H), 3.85 (dd, J=3, and J=6, 1H). 4.62 (m, 1H), 7.20 (s, 1H), 7.65 (d, 1H).
EXAMPLE 10
4(S)-Methyl-[[3(S)-[[(t-butyloxycarbonyl]amino]-2-oxo-1-azetidinyl]imino]acetic acid; (8b)
A solution of 3.0 g (8.3 mmol) of benzyl[[4-(S)-methyl-3(S)-[(t-butyloxycarbonyl)amino]-2-oxo]imino]acetate and 500 mg of 5% palladium on carbon in 70 ml of tetrahydrofuran was hydrogenated at atmospheric pressure for 3 hours and worked up as described in Example 9 to afford a foam: yield 2.58 g; IR (KBr) 1780 cm -1 ; NMR (CDCL 3 ) δ1.45 (s, 9H, (CH 3 ) 3 C), 1.62 (d, 3H, J=8 Hz, CH 3 ), 4.25 (m, 2H), 8.75 (s, 1H=CH).
EXAMPLE 11
(S)-[(3-Amino-2-oxo-1-azetidinyl)imino]acetic acid trifluoroacetate; (9a)
A solution of 2.72 g (10 mmol) of 3-(t-butyloxycarbonylamino)-2-oxo-1-azetidinyliminoacetic acid in 10 ml of trifluoroacetic acid was stored at room temperature for 16 hours, then was evaporated to dryness in vacuo. The resulting oil was triturated to a solid with ether to afford 3.18 g of the desired salt; IR (KBr) 1780 cm -1 (β-lactam C═O); NMR (d 6 DMSO) δ3.4 (dd, 1H, J=2.5 and 5.5 Hz), 4.25 (1H, t, J=5.5 Hz), 4.65 (dd, 1H, J=2.5 and 5.5 Hz.), 7.26 (s, 1H), 8.0-9.2 (m, 3H).
EXAMPLE 12
[[(S)-3-Amino-4-oxo-2-(S)-methyl-1-azetidinyl]imino]acetic acid trifluoroacetate; (9b)
The procedure of Example 11 was followed using 4(S)-methyl-[[3(S)-[[(t-butyloxycarbonyl]amino]-2-oxo-1-azetidinyl]imino]acetic acid in place of 3-(t-butyloxycarbonylamino)-2-oxo-1-azetidinyliminoacetic acid to afford the product of the example, mp 172°-174° C. dec; IR (KBr) 1780 cm -1 ; NMR (TFA) δ1.80 (d, 3H, J=8 Hz), 4.65 (broad s, 1H, 3αH), 4.80 (d, 1H, J=8 Hz, 4H).
EXAMPLE 13
(S)-3-[2-(2-Amino-4-thiazolyl)]-(Z)-2-methoxyiminoacetylamino-2-(S)-methyl-4-oxo-1-azetidinyliminoacetic acid; (12b)
A mixture of 687 mg (3.42 mmol) of 2-(2-amino-4-thiazolyl-(Z)-2-methoxyiminoacetic acid, 705 mg (3.42 mmol) of dicyclohexylcarbodiimide and 523 mg (3.42 mmol) of 1-hydroxybenzotriazole in 18 ml of N,N-dimethylformamide was stirred at room temperature for 20 minutes. To this mixture was added a mixture of 830 mg (3.42 mmol) of [[(S)-3-amino-4-oxo-2-(S)-methyl-1-azetidinyl]imino]acetic acid trifluoroacetate, 1.30 ml (7.70 mmol) of chlorotrimethylsilane and 1.07 ml (7.70 mmol) of triethylamine in 15 ml of N,N-dimethylformamide. The resulting mixture was stirred at room temperature for 16 hours and then was filtered. The filtrate was diluted with 100 ml of water and extracted with two 50 ml portions of ethyl acetate. The aqueous phase was stirred for several hours with 50 ml of granular carbon. The liquid was decanted and the carbon was washed several times with water, then stirred for several hours with 50% v/v aqueous acetone (pH 3). The mixture was filtered and the filtrate was evaporated to dryness in vacuo. The residue was dissolved in a small amount of dimethyl sulfoxide and precipitated by the addition of ether to give the desired product; IR (KBr) 1775 cm -1 (β-lactam C═O); NMR (d 6 DMSO+TFA) δ1.50 (d, 3H), 4.05 (s, 3H), 4.35 (m, 1H), 4.65 (d, 1H), 7.18 (s, 1H), 7.50 (s, 1H).
EXAMPLE 14
Allyl(S)-3-[t-Butyloxycarbonylamino]-2-oxo-1-azetidinyliminoacetate (14 a)
A solution of 3.74 g (18.6 mmol) of S-3-[t-butyloxycarbonylamino]-2-oxo-1-aminoazetidine and 2.38 g (18.6 mmol) of allyl glyoxylate in 125 ml of toluene was heated at reflux for one hour using a water separator. The solution was then evaporated to dryness in vacuo. The residue was dissolved in dichloromethane and filtered through hydrous magnesium silicate. The filtrate was evaporated in vacuo to give 3.30 g (60%) of the desired product as a yellow glass; M + (FAB)297; IR(mull)1795 cm -1 (β-lactam C═O), 1720 cm -1 (ester C═O); NMR (CDCl 3 ) δ1.45 (s, 9H, (CH 3 ) 3 C), 3.77 (dd, 1H, J=3.1, and 6.8 Hz, H 4 β), 4.02 (dd, 1H, J=6.8 and 6.4 Hz, H 4 α), 4.77 (d, 2H, J=5; 9 Hz, O CH 2 ), 4.80 (m, 1H, H 3 α), 5.20 (d, 1H, NH), 5.30 (d, 1H, J=10 Hz, allyl cis H), 5.38 (d, 1H, J=15.8 Hz, allyl trans H), 5.96 (m, 1H, CH2CH═), 7.44 (s, 1H, N═CH).
EXAMPLE 15
Allyl (S)-[(3-Amino-2-oxo-1-azetidinyl)imino]acetate trifluoroacetate (15a)
A solution of 2.97 g (9.76 mmol) of allyl (S)-3-[t-butyloxycarbonylamino]-2-oxo-1-azetidinyliminoacetate in 40 ml of trifluoroacetic acid was stored at room temperature for 1.0 hour. Then the solution was evaporated to dryness in vacuo at 35° C. The resulting oil was triturated to a solid with diethyl ether to afford 2.01 g (67%) of the desired salt; IR(KBr) 1775 cm -1 (β-lactam C═O); NMR (DMSO) d 3.72 (dd, 1H, J=3.1 and 6.8 Hz, H 4 β), 4.07 (dd, 1H, J=6.8 and 6.0 Hz, H4α), 4.66 (dd, 1H, J=2.8 and 6.0 Hz), 4.75 (d, 2H, J=5.5 Hz, --OCH 2 --), 5.28 (d, 1H, J=10 Hz, allyl cis H), 5.37 (d, 1H, J=16.8 Hz, allyl trans H), 5.98 (m, 1H, CH 2 CH═), 7.40 (s, 1H, N═CH), 8.90 (broad s, 3H, +NH 3 ).
EXAMPLE 16
Allyl (S)-3-[(2-amino-4-thiazolyl)-(Z)-2-methoxyiminoacetylamino]-2-oxo-1-azetidinyliminoacetate (16)
A mixture of 2.0 g (10.0 mmol) of 2-(2-amino-4-thiazolyl)-(Z)-2-methoxyiminoacetic acid, 2.06 g (10.0 mmol) of dicyclohexylcarbodiimide and 1.53 g, (10.0 mmol) of 1-hydroxybenzotriazole in 50 ml of N,N-dimethylformamide was stirred at room temperature for 20 minutes. To this mixture was added a mixture of 3.12 g (10.0 mmol) of allyl (S)-[(3-amino-2-oxo-1-azetidinyl)imino]acetate trifluoroacetate and 2.08 ml (15.0 mmol) of triethylamine in 25 ml of N,N-dimethylformamide. The resulting mixture was stirred at room temperature for 16 hours and then was filtered. The filtrate was evaporated in vacuo at 40° C. to remove the N,N-dimethylformamide and the residue was chromatographed on silica gel using ethyl acetate as the eluent to afford 1.56 g (41%) of product: IR (KBr) 1777 cm -1 (β-lactam C═O), 1719 cm -1 (ester C═O). NMR (DMSO) δ3.68 (dd, 1H, J=3.1 and 6.8 Hz, H 4 β), 3.85 (s, 3H, CH 3 ), 4.06 (dd, 1H, J=6.8 and 6.4 Hz, H 4 α), 4.74 (d, 2H, J=5.5 Hz, OCH 2 ). 5/01 (m, 1H, H 3 α), 5.28 (d, 1H, J=10 Hz, allyl cis H), 5.38 (d, 1H, J=16.2, allyl trans H), 5.98 (m, 1H, CHCH═), 6.74 (S, 1H, thiazole H), 7.24 (s, 2H, NH 2 ), 7.28 (s, 1H, N═CH), 9.31 (S, 1H, NH).
EXAMPLE 17
Potassium S-[[3-[[(2-amino-4-thiazolyl)-(Z)-(methoxyimino)-acetyl]amino]-2-oxo-1-azetidinyl]imino]acetate (12a)
A mixture of 180 mg (0.47 mmol) of allyl (S)-3-[(2-amino-4-thiazolyl)-(Z)-2-methoxyiminoacetylamino]-2-oxo-1-azetidinyliminoacetate, 38 mg of tetrakis(triphenylphosphine)palladium (O), 27 mg of triphenylphosphine and 1.0 ml of 0.5M potassium 2-ethylhexanoate solution (in ethyl acetate) in 10 ml of dichloromethane and 5 ml of ethyl acetate was stirred at room temperature under nitrogen for 40 minutes. The reaction mixture was diluted with 20 ml of ether and the resulting solid was collected by filtration. The solid was dissolved in a small volume of water, treated with activated charcoal, filtered and lyophilized to give 38.0 mg of the product of the example: IR (KBr) 1764 cm -1 (β-lactam C═O). NMR (DMSO) δ3.84 (S, 3H, CH 3 O), 3.85 (m, 2H, H 4 α and H 4 β), 4.92 (m, 1H, H 3 α), 6.75 (S, 1H, thiazole H), 7.00 (S, 1H, CH═N), 7.22 (S, 2H, NH 2 ), 9.22 (d, 1H, J=7.5 Hz, --NH).
|
The disclosure describes (S)-3-[2-(2-amino-4-thiazolyl)]-(Z)-2-methoxyiminoacetylamino-2-oxo-1-azetidinyliminoacetic acid and (S)-3-[2-(2-amino-4-thiazolyl)]-(Z)-2-methoxyiminoacetylamino-2-(S)-methyl-4-oxo-1-azetidinyliminoacetic acid and the cationic salts thereof which possess antibacterial activity.
| 2
|
BACKGROUND OF THE INVENTION
The present invention relates to a process for the preparation of alpha-haloalkyl esters.
Alpha-haloalkyl esters are useful and versatile intermediates having two different reactive groups attached to one carbon atom. They can be used for the preparation of acycloxyalkyl esters by reaction with carboxylic acids or their alkali or silver salts, for example in order to obtain pharmaceuticals (cf. French Demande 2,164,489 or German Offenlegungsschrift 2,706,413). They may also be used for the preparation of alpha-acycloxy nitriles by reaction with alkali cyanides which nitriles can be used as plant protective agents (cf. German Offenlegungsschrift 2,919,974).
Alpha-haloalkyl esters may further be used for the preparation of fulvenes for example by reacting an alpha-haloalkyl ester of acetic acid with sodium cyclopentadienide followed by elimination of acetic acid (cf. Helv. Chim. Acta 54 (1971) pp. 1037-1046). Fulvenes can be applied as anti-knock compounds in fuels for combustion engines (cf. U.S. Pat. No. 2,589,969) or as components of polymer compositions (cf. U.S. Pat. No. 3,390,156).
Alpha-haloalkyl esters have hitherto been prepared by procedures such as chlorination of alkyl esters or addition of a hydrogen halide to alpha-alkenyl esters or by reacting an acyl halide with an aldehyde. The reaction last mentioned appears to be the most useful and widely used method for preparing alpha-haloalkyl esters (cf. Acta. Chem. Scand. 20 (1966) pp. 1273-1280).
It has now been found that alpha-haloalkyl esters can simply be prepared by reacting an acyl halide with hydrogen thereby avoiding the separate preparation of an aldehyde necessary in the known methods mentioned above.
SUMMARY OF THE INVENTION
The present invention therefore provides a process for the preparation of alpha-haloalkyl esters in which an acyl halide having the general formula ##STR2## in which R 1 represents a substituted or unsubstituted hydrocarbyl group and Hal represents chlorine or bromine is contacted with hydrogen at elevated temperature and pressure in the presence of a catalytic system comprising at least one Group VIII element.
DESCRIPTION OF PREFERRED EMBODIMENTS
The group R 1 containing 1-20 carbon atoms may be an aryl, alkyl, alkaryl or aralkyl group which, optionally, may be substituted with one or more inert substituents such as fluorine or chlorine or alkoxy, phenoxy or alkanoyl groups. Preferably R 1 is an alkyl group having 1-20 carbon atoms. Most preferably R 1 is an unsubstituted alkyl group having 1-4 carbon atoms. The process of the invention is particularly suitable for the preparation of the alpha-chloroethyl esters of acetic acid from acetyl chloride.
The catalytic system used in the process of the invention comprises preferably palladium, rhodium or ruthenium.
Palladium can be used in a homogeneous catalytic system comprising palladium compounds soluble in the reaction mixture such as palladium chloride dihydrate or organic palladium salts or complexes such as palladium acetate or palladium acetyl-acetonate. Preferably the catalyst system is a heterogeneous catalyst comprising palladium metal on a carrier such as for example carbon.
Rhodium is preferably used in a homogeneous catalytic system comprising a rhodium compound soluble in the reaction mixture. Examples of suitable rhodium compounds are rhodium (III) hydroxide, rhodium (III) chloride, rhodium (III) chloride trihydrate, rhodium (III) bromide, rhodium (III) iodide and the corresponding pyridine and phosphine complexes such as tris(pyridine) rhodium (III) chloride or dichloro bis(triphenylphosphine) rhodium, rhodium (III) formate, rhodium (III) acetate, rhodium (III) butyrate, rhodium (III) naphtenate, dirhodium octacarbonyl, tetrarhodium dodecacarbonyl, hexarhodium hexadecacarbonyl, rhodium dicarbonyl acetylacetonate and other organorhodium complexes. Preference is given to the use of rhodium (III) chloride trihydrate.
Ruthenium is also preferably used in a homogeneous catalytic system comprising a ruthenium compound soluble in the reaction mixture. Examples of suitable ruthenium compounds are ruthenium (III) chloride, ruthenium (III) chloride trihydrate, organic ruthenium salts or complexes such as ruthenium (III) propionate, ruthenium (III) butyrate, ruthenium pentacarbonyl, triruthenium dodecacarbonyl and mixed ruthenium halocarbonyls such as bis-(ruthenium tricarbonyldibromide) and other organoruthenium complexes.
The amount of Group VIII elements to be used in the process of the invention is not critical and any amount which exerts catalytic activity can be used. Amounts as low as 0.001% by wt calculated on the amount of acyl halide ##STR3## can be used, preference being given to amounts in the range of from 0.005 to 10% by wt, most preferably between 0.01 and 5% by wt on the same basis.
The catalytic system used in the process of the invention may comprise a promoter or combinations of promoters. Suitable promoters are iodide or bromide sources such as for example elemental iodine, elemental bromine, hydrogen iodide, hydrogen bromide and metal iodides or bromides. Examples of metal iodides or bromides comprise iodides or bromides of alkali metals such as lithium iodide or sodium iodide, zinc iodide, zinc bromide, chromium (III) iodide, cobalt (II) iodide and nickel (II) iodide. Other iodide sources which can be used conveniently comprise organic iodine compounds such as alkyl, aryl, aralkyl or acyl iodides having up to 12 carbon atoms. Preference is given to the use of methyl iodide. The quantity of the iodide or bromide source added to the reaction mixture is not crucial. Suitably the amount of iodide and/or bromide source is in the range of from 0.1 to 1000, preferably from 1 to 500 and especially from 10 to 300 gram atoms I or Br per gram atom Group VIII element.
The process according to the invention may also be carried out in the presence of a catalytic system comprising one or more Group Va compounds as promoters. Suitable Group Va compounds consist of compounds represented by the general formula ##STR4## in which X is a Group Va element having a valency of 3 or higher, selected from N, P, As or Sb; Y is a Group VIa element selected from O, S or Se; n is 0 or 1; either a, b and c are 0 or 1 and R 2 , R 3 and R 4 are similar or dissimilar optionally substituted hydrocarbyl groups, or a and b are 0 and c is 0 or 1 and R 2 and R 3 form together with X a heterocyclic group; or a, b and c are 0 and R 2 , R 3 and R 4 form together with X a heterocyclic aromatic ring system. Preference is given to compounds represented by the general formula II in which X is N or P and Y is 0 and a, b an c are 0. In these compounds the group R 2 , R 3 and R 4 are preferably similar or dissimilar alkyl groups containing 1-12 carbon atoms or cycloalkyl, aryl or alkaryl groups containing 5-12 carbon atoms optionally substituted with groups which are substantially inert in the reaction medium such as chlorine, alkoxy groups, carboxylic (ester) groups, oxo groups or sulphone or sulphoxide groups. When X is N, preferably the nitrogen atom and R 2 , R 3 and R 4 form together a heterocyclic aromatic ring system.
Very suitable promoters are tertiary amines and the oxides thereof such as triethylamine, tri-n-butylamine, triethylamine oxide, N,N-dimethyl phenylamine, N-methyl piperidine oxide, dimethyl octylamine oxide; amides such as N,N-dimethyl acetamide or N-methyl pyrrolidone (N-methylbutyrolactam); tertiary phosphines and the oxides thereof such as tri-n-butylphosphine, tri-n-butylphosphine oxide, triethylphosphine, triethylphosphine oxide, tricyclohexylphosphine, tricyclohexylphosphine oxide, triphenylphosphine, triphenylphosphine oxide, tri-p-tolylphosphine oxide, tri-p-chloro phenylphosphine; and heterocyclic aromatic nitrogen compounds such as pyridine, pyridine oxide and methyl substituted pyridines and the oxides thereof. Most preferred are triphenylphosphine, triphenylphosphine oxide, pyridine and pyridine oxide.
The amount of Group Va compound represented by the general formula II to be used in the process of the invention is not critical and may be in the range of from 0.01 to 200 moles Group Va compound per gram atom Group VIII element. As stated hereinbefore the catalytic system used in the process of the invention may comprise combinations or promoters. Preference is given to combinations of two or more of the compounds methyl iodide triphenylphosphine and triphenylphosphine oxide.
It will be appreciated that in the reaction mixture salts or complexes may be formed by the reaction of the oxide, sulfide or selenide of the tertiary N, P, As or Sb compounds with the iodine or bromine compound present. Examples of such salts and complexes are alkoxy pyridinium salts for example methoxy pyridinium iodide formed from pyridine oxide and methyl oxide and the complexes [(C 6 H 5 ) 3 PO--H--OP(C 6 H 5 ) 3 ] + I 3 - or [(C 2 H 5 ) 3 AsO--H--OAs(C 2 H 5 ) 3 ] + I - . Consequently the use of such salts or complexes when prepared separately is within the scope of the present invention. Furthermore it will be appreciated that the oxides of the phosphines having the formula II can be formed in situ from the corresponding phosphines by carrying out the reaction in the presence of molecular oxygen or hydrogen peroxide.
The process according to the present invention can be carried out using a temperature in the range from about 50° C. to about 250° C. Preference is given to a temperature in the range of 100° C. to 200° C. and particularly in the range of 130° C. to 170° C. The contacting of the staring material with hydrogen according to the invention can be carried out at pressures as low as 5 bar. Pressures in the range of 20 to 100 bar are preferred. Higher pressures, for example pressures as high as 1000 bar, can be applied, but they are generally not economical because of the investments and energy costs involved.
The hydrogen used in the process of the invention may contain inert gases such as for example nitrogen, noble gases, carbon dioxide or methane. In the case that a homogeneous catalyst is used the hydrogen may contain carbon monoxide. The use of mixtures of hydrogen and carbon monoxide, i.e., synthesis gas, has the advantage that such mixtures are easily available. Moreover, when carbon monoxide is present in the reaction mixture, the starting acyl halides may be formed in situ from a halide R 1 Hal and carbon monoxide is desired. The amount of carbon monoxide present in the hydrogen is not critical. The molar ratio of carbon monoxide to hydrogen may be in the range of 0 to 10, preferably in the range of 0 to b 2.
The preparation of alpha-haloalkyl esters according to the process of the invention by converting an acyl halide with hydrogen can be expressed by the following chemical equation: ##STR5## If desired when a homogeneous catalyst is used the formation of HCl can be suppressed by carrying out the reaction in the presence of an ester, preferably having the formula ##STR6## in which R 5 is identical to the group R 1 in the starting acyl halide ##STR7## and carbon monoxide. When for example the conversion of acetyl chloride is carried out in the presence of methyl acetate and carbon monoxide the following reaction take place: ##STR8## By carrying out the reaction in this way all the chlorine present in the starting acetyl chloride turns up in the product obtained.
The process of the invention may be carried out in the gaseous or liquid phase. Preference is given to the liquid phase. If desired the reaction mixture may contain a solvent. Suitable solvents include carboxylic acids such as acetic acid and propanoic acid, carboxylic acid esters such as methyl acetate and cyclic esters such as butyrolactone. Ethers can also be used as solvent, for example dimethyl ether, diethyl ether, methyl-t-butyl ether, diglyme and tetraglyme, and cyclic ethers such as tetrahydrofuran, 1,4-dioxane, 1,3-dioxane and the dioxalanes. Other compounds which can be used as solvent include sulphones and sulphoxides. Examples of such compounds are dimethyl sulphone, diethyl sulphone, methyl ethyl sulphone, methyl butyl sulphone, sulpholane, 2-methylsulpholane, 3-methyl-sulpholane, 2-methyl-4-butyl sulpholane, dimethyl sulphoxide and diethyl sulphoxide. The reaction time is not critical and will depend on the temperature and the pressure applied. Reaction times of from 0.25 to 30 hours are sufficient, preference being given to reaction times in the range of from 1 to 20 hours. The process according to the invention can be carried out batch wise, semi-continuously or continuously. The reaction section may comprise one or more autoclaves or one or more reactor tubes the walls of which are made of or coated with inert materials. The reaction products may be isolated by techniques known in the art.
The following examples illustrate the invention.
EXAMPLE I
The experiments 1-6 in this example were carried out using the same technique. The conditions and results of these experiments are given in Table A. A Hastelloy C (Trade Mark) 300 ml magnet driven autoclave was charged with acetyl chloride, RhCl 3 .3H 2 O, optionally with triphenylphosphine oxide, a mixture of triphenylphosphine oxide and triphenylphosphine or a mixture of triphenylphosphine oxide and methyl iodide. The vessel was flushed with carbon monoxide and then pressurized with hydrogen and carbon monoxide each having a partial pressure of 20 bar at room temperature. The autoclave was then heated to a fixed temperature and kept at this temperature during a reaction time indicated in Table A. The pressure was maintained during this reaction by feeding in hydrogen.
After the reaction the reaction mixture was analyzed by gas-liquid chromatography; the alpha-chloroethyl ester of acetic acid was produced at a conversion and selectivity as indicated in Table A. The main by-product appeared to be ethylidene diacetate and/or acetaldehyde.
TABLE A__________________________________________________________________________Catalytic system Acetyl H.sub.2 partial CO partial Group VIII metal Promotor chloride pressure pressure temperature reaction conversion.sup.(1) selectivity.sup.(2 )Exp. compound m.mol. m.mol. ml. bar bar °C. time hrs. % %__________________________________________________________________________1 RhCl.sub.3.3H.sub.2 O 0.5 50 20 20 160 15 10 852 RhCl.sub.3.3H.sub.2 O 0.5 Ph.sub.3 P═O 3 50 20 20 160 15 30 903 RhCl.sub.3.3H.sub.2 O 0.5 Ph.sub.3 P 3 50 20 20 160 15 25 90 Ph.sub.3 P═O 0.254 RhCl.sub.3.3H.sub.2 O 0.5 Ph.sub.3 P 3 50 20 20 150 15 15 90 Ph.sub.3 P═O 0.255 RhCl.sub.3.3H.sub.2 O 0.5 CH.sub.3 I 10 50 20 20 135 15 20 90 Ph.sub.3 P 1.56 RhCl.sub.3.3H.sub.2 O 0.5 25* 30 30 150 15 40 60__________________________________________________________________________ ##STR9## ##STR10## *acetic acid 25 ml present
EXAMPLE II
A Hastelloy C (Trade Mark) magnet driven autoclave was charged with 25 ml acetyl chloride, 28 ml methyl acetate, 1 mmol RhCl 3 .3H 2 O and 3 mmol triphenyl phosphine. The vessel was then flushed with carbon monoxide. After pressurizing with hydrogen and carbon monoxide having partial pressures of 20 bar the autoclave was heated to 160° C. and kept at this temperature during 15 hours. The pressure was maintained constant during this time by feeding in hydrogen and carbon monoxide at a ratio of 1:1 corresponding with the partial pressures. After the reaction mixture was analyzed by gas-liquid chromatography the alpha-chloroethyl ester of acetic acid was formed at a conversion of 20% and a selectivity of 85%. The above experiment was repeated except that an amount of 0.25 mmol triphenylphosphine oxide was added as an additional promoter. Conversion and selectivity were 15% and 90% respectively.
The last experiment was repeated except that after flushing an amount of 11.5 g methylchloride was added. The alpha-chloroethyl ester of acetic acid was formed at a conversion of 26% and a selectivity of 92%.
EXAMPLE III
A Hastelloy C (Trade Mark) 300 ml magnet driven autoclave was charged with 50 ml acetyl chloride and 0.5 g of a catalyst consisting of 3% by weight of palladium on carbon. After flushing with carbon monoxide and pressurizing to 50 bar with hydrogen the vessel was heated to 150° C. The vessel was kept at this temperature during 2.5 hours maintaining the pressure at 50 bar by feeding in hydrogen. Gas-liquid chromatography analysis of the reaction mixture showed that the alpha-chloroethyl ester was produced at a conversion of 100% and a selectivity of 60%. The above experiment was repeated except that the temperature of the vessel was kept at 90° C. during 15 hours. The alpha-chloroethyl ester of acetic acid was produced at a conversion of 80% and a selectivity of 85%.
|
A process for the preparation of alpha-haloalkylesters, wherein an acylhalide having the general formula ##STR1## in which R 1 represents a substituted or unsubstituted hydrocarbyl group and Hal represents chlorine or bromine is contacted with hydrogen at elevated temperature and pressure in the presence of a catalytic system comprising at least one Group VIII element.
| 2
|
BACKGROUND OF THE INVENTION
This invention relates to a hydraulically operated valve with controlled lift, in particular a fuel/gas injection valve for internal combustion engines, comprising a stop face that is fixed on the valve stem. With the use of such valves a particularly high thermal efficiency may be achieved in internal combustion engines. At the beginning of the working stroke a defined volume of gas is taken from the respective cylinder and is stored temporarily in a storage cell. The fuel is injected into this temporary storage cell. In this way distribution of the fuel in the stored volume is permitted to last for almost as long as the entire working cycle of the engine. The valve opens during the subsequent compression stroke.
DESCRIPTION OF THE PRIOR ART
Valves are known which have a plunger with a stop face. This stop face cooperates with a counter-face in the valve casing, limiting the maximum valve lift. In order to adjust the injection process to different operating parameters of the engine it has proved necessary and desirable, however, to be able to make adjustable the maximum valve lift.
SUMMARY OF THE INVENTION
It is an object of the invention to avoid the above disadvantages and to provide a valve in which the maximum valve lift may be adjusted precisely to suit specific operating conditions. Differences in thermal expansion, wear, etc., should not affect the accuracy of valve adjustment.
For this reason the invention proposes the use of a stop cam, which is mechanically driven via a friction clutch and which cooperates with the stop face, maximum valve lift being obtained by rotating the stop cam through a defined angle, and contact between the cam and the stop face being obtainable even when the valve is in its closed position. In addition, a control unit is provided for control of the cam drive in accordance with the operational state of the engine.
Thus the valve always has two extreme positions, i.e., one defined by the valve disk sitting in the valve seat, and the other one defined by the stop face having arrived at the stop cam. The stop cam is arranged such that it may be brought into contact with the stop face even when the valve is closed. In this way it is possible for the stop cam to return to an initial position after every working stroke of the valve, in which the cam is in contact with the stop face when the valve is closed.
This will provide a well-defined starting position for the rotatory movement of the stop cam performed for limiting the subsequent opening of the valve. In this manner differences in thermal expansion and wear may be compensated.
Preferably, the stop cam is driven by an electric motor, i.e., preferably a stepping motor. This will ensure a quick response of the adjusting mechanism to the control pulses. Depending on the required accuracy and the specific application an ordinary servo-motor or a stepping motor may be used.
In a multi-cylinder engine the use of a single motor is recommended for actuating several stop cams in the valves of several cylinders. This will simplify the design considerably, doing away with complex components and reducing control expense. In this way all cams are reset and the desired state free from play is achieved at a time when all valves are closed, for example, when the fuel-supply is cut off during the use of the engine brake.
It is of special advantage if the friction clutch is placed in a recess of the stop cam. This will result in a particularly compact design.
Provisions may be made for the driving shaft to penetrate the valve casings, the assemblies consisting of friction clutch and stop cam being placed inside the valve casings. Thus the valve itself serves as a housing for the more sensitive components, i.e., in particular, the friction clutch. Only the driving gear is situated outside of the valves.
It is provided in a preferred variant of the invention that the friction clutch transmit a lesser torque in the direction of rotation causing the stop cam to approach the stop face than in the opposite direction. During the resetting phase the motor will press the cam against the stop face of the closed valve. The force applied during this process will correspond to the torque the friction clutch transmits in closing direction. In order to ensure that the stop cam is released even if it seizes on the stop face due to unfavorable conditions of friction, a higher torque may be required. This torque may be provided by a suitable friction clutch.
Such a clutch must have at least one cheek which is in contact with the inside of a cylindrical surface against which it is pressed by a spring, whereupon the transmitted torque is self-amplified in one direction of rotation due to the fact that the clutch-cheek is held to the driving shaft of the clutch at one of its ends. The friction clutch thus works like a shoe brake.
It is recommended to provide a control unit for the motor, which will utilize given performance characteristics and data on the operational state of the engine to control the maximum valve lift by rotation of the stop cam, and which will effect a reverse rotation of the cam when the valve is closed, during which reverse rotation the rotating angle of the motor is larger than would correspond to the return to the theoretical reset-position. If the motor is configured as a stepping motor the control unit will effect a predetermined number of steps before the opening of the valve, corresponding to a given rotating angle of the stop cam and thus a given maximum valve lift, and it will further initiate a number of steps to be taken in opposite direction after the closing of the valve, which is larger than the one before the opening of the valve. This will ensure that the stop cam will press against the stop face without any play, even if there are dimensional changes due to wear or thermal loads. The excess movement of the motor is taken up by the friction clutch. Basically, such a resetting process may take place during each working cycle. It will suffice, however, to perform this process occasionally, for instance, when the fuel-supply is cut off during the use of the engine brake.
It is recommended to close the valve by means of a hydraulic plunger, preferably actuated by the fuel, which acts against the force of a spring. This will permit a particularly simple design of the device.
Further simplification is achieved by making one surface of the hydraulic plunger serve as a stop face at the same time.
In a special variant of the invention a gas storage cell is provided for a volume of gas taken from the cylinder of an internal combustion engine, as well as a fuel injection device for feeding the fuel into this gas storage cell. With this type of fuel/gas injection valve maximum thermal efficiency may be achieved in an internal combustion engine.
It may further be provided that the valve be thermally insulated vis-a-vis the cylinder head of the engine. In this way the temperature of the valve is increased considerably, which will prevent the formation of carbon deposits and encourage self-cleaning.
It is a special advantage if the maximum valve lift is limited by the stop cam to a value between 0 and 0.5 mm.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be further described by way of example only with reference to the accompanying drawings, in which
FIG. 1 is a schematical view of a valve as proposed by the invention, presented as a section;
FIG. 2 gives a section of a friction clutch;
FIG. 3 is a section along line III--III in FIG. 2;
FIG. 4 is a schematical view of a variant of the invention with a common valve drive in a multi-cylinder engine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a fuel/gas injection valve 1 located in the cylinder head 2 of an internal combustion engine not shown here in detail. The valve stem 3, which is axially moveable, has a valve disk 4 on its end, closing off the opening between the combustion chamber 5 and the mixer chamber 6 inside the valve 1. A hydraulic plunger 7 is permanently attached to the valve stem 3, sealing a control chamber 8 in the valve 1. The hydraulic plunger 7 is acted upon by a pressure spring 9, which is used to shift the valve 1 into its open position. The mixer chamber 6 and the control chamber 8 are separated by a seal 10.
The lift of the valve 1 is limited by a stop cam 11. This cam 11 cooperates with a stop face 12 located on the hydraulic plunger 7. Via a shaft 13 the cam 11 is in contact with a friction clutch 14 driven by an electric stepping motor 16 via another shaft 15. The stop cam 11 is located such that it may be brought into contact with the stop face 12 even when the valve 1 is in its closed position.
Before the valve 1 opens, a control unit 17 will give a control command to the stepping motor 16, which will then perform a number of steps corresponding to the desired opening of the valve 1.
Operation of the valve is as follows. An amount of fuel is taken from a tank 18 with the use of a feed pump 19. A pressure control valve 20 will maintain constant pressure in the fuel line 21. In a metering unit 22 of a known type, which is supplied from the line 21, the fuel volume is metered for injection. Via a check valve 23 with a slight pre-load and a nozzle 24 the fuel is injected into the mixer chamber 6. The check valve 23 is located as close as possible to the valve 1, in order to minimize evaporation losses. Fuel injection takes place as soon as the valve 1 has closed. At this time the pressure in the mixer chamber 6 is 2-20 bar. The corresponding cylinder of the internal combustion engine is performing its working stroke.
The valve 1 opens during the compression stroke. By that time the injected fuel will have completely evaporated and been uniformly distributed in the mixer chamber 6. Before the opening of the valve the stop cam 11 is brought into the position described above, i.e. limiting the valve lift. Opening is affected via a solenoid-controlled three-way valve 25, which switches to depressurize the control chamber 8 filled with fuel. The pressure spring 9 pushes the hydraulic plunger 7 downwards, until the stop face 12 touches the stop cam 11. At this time the pressure in the combustion chamber 5 is lower than in the mixer chamber 6, and the content of the mixer chamber 6 will flow into the combustion chamber 5. The valve 1 will remain open until after the beginning of the working stroke, and gases from the combustion chamber 5 will flow back again into the mixer chamber 6. The time of closing of the valve 1 is chosen such that the pressure in the mixer chamber 6 is sufficiently high for the next injection (2-20 bar), while the flame front is reliably prevented from entering the mixer chamber 6. The closing of valve 1 is effected by another switch of the three-way valve 25, whereby pressurized fuel from the line 21 is forced into the control chamber 8. The hydraulic plunger 7 moves upwards, closing the valve 1 against the force of the pressure spring 9.
When the fuel mixture is injected into the combustion chamber 5 it is distributed best if an atomizing device 26 is provided for diffusion of the gas jet, with one or more holes 27. In order to prevent the formation of carbon deposits the valve 1 is thermally insulated against the cylinder head 2. Oil carbon mainly forms in a temperature range of 150°-180° C. If the valve is operated above 180° C. it becomes self-cleaning, which will extend its working life considerably. This is facilitated by providing a gap 28 between the valve 1 and the cylinder head 2. Besides, the sealing 29 between valve and cylinder head 2 may be made of material with extremely poor thermal conductivity.
The friction clutch 14 shown in FIGS. 2 and 3 has a cheek 30 which is in contact with the inside of a cylindrical surface 31 worked into the shaft 13. The cheek 30 is attached to a part 33 of the shaft 15 by means of a pin 32. A helical spring 34, which is held in a recess 35 of the shaft 15, presses the cheek 30 against the cylindrical surface 31. The pin 32 and the helical spring 34 act upon opposite ends of the cheek 30 of the clutch 14. In this way it is possible to transmit different torques via the friction clutch 14, which will vary with the sense of rotation of the shaft 15. If the shaft 15 is driven in the direction of the arrow 36, the cheek 30 is pressed against the cylindrical surface 31 by the pin 32 and the helical spring 34, with a force that increases with the transmitted torque. As a result of this self-amplification comparatively large torques may be transmitted. The sense of direction indicated by the arrow 36 corresponds to the movement of the stop cam 11 away from the stop face 12. On the other hand the cheek 30 is pulled away from the cylinder face 31 if the shaft 15 is turned in the opposite direction, and the transmitted torque is considerably smaller.
In the variant of the invention shown in FIG. 4 a joint motor 16 is provided for driving several stop cams 114 of an internal combustion engine not shown here. The driving shaft 115 penetrates the valve casings 101 in the area of the control chambers 108. The driving shaft 115 consists of several sections connected by flanges 90. The stop cam 111 is constituted by the outer contour of the friction clutch 114. Inside this stop cam 111 a cylindrical surface 31 is provided, against which is pressed the clutch cheek 30. The clutch cheek 30 is attached to the shaft 115 by means of a pin 32. A helical spring 34, which is held in a ring 91 screw-fastened on the shaft 115, presses the cheek 30 against the cylindrical surface 31. The axis 92 of the shaft 115 is situated outside of the plane formed by the axes 93 of the valves 101, such that the valve stem 103 and the driving shaft 115 do not intersect.
|
A hydraulically operated valve with controlled lift, in particular a fuel/gas injection valve for internal combustion engines, has a stop face fixed on the valve stem. For accurate control of the opening of the valve a stop cam is provided, which is drivn mechanically via a friction clutch, and which cooperates with the stop face. By rotating the cam through a predetermined angle the maximum valve lift will be obtained. The cam may be brought into contact with the stop face even in the closed position of the valve.
| 5
|
FIELD OF THE INVENTION
This invention relates to engine valve timing control systems and to methods of valve timing control.
BACKGROUND OF THE INVENTION
It is known in the art to provide for control of engine valve lift and timing using a preferably electronic control actuating a solenoid valve to control discharge of fluid from one or more lost motion hydraulic valve actuators driven by an engine camshaft. One such valve timing control system is shown, for example, in the U.S. Pat. No. 4,615,306 Wakeman issued Oct. 7, 1986.
In order to provide soft seating of the engine valves, lost motion actuators for use in such systems have been provided with means for damping the valve seating action as described, for example, in U.S. Pat. Nos. 5,158,048 Robnett issued Oct. 27, 1992, and 5,216,988 Taxon issued Jun. 8, 1993.
SUMMARY OF THE INVENTION
The present invention provides simplified lost motion actuator arrangements as well as a system and method of valve timing control which eliminates the need for hydraulic damping in the actuator and allows seating of the valve to be controlled by a preferably constant velocity seating ramp formed on the actuating cam. The method involves discharging hydraulic fluid from the actuator at any time up to about the peak of the cam lift curve followed by hydraulic closing of the valve until it contacts the seating ramp near the valve closed position. At this point, fluid discharge is cut off and the valve is seated by the actuator moving along the valve seating ramp. A system including control of multiple actuators by a single solenoid valve without the use of intermediate check valves is also provided, as are various embodiments of simplified hydraulic actuators.
These and other features and advantages of the invention will be more fully understood from the following description of certain exemplary embodiments of the invention taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a fragmentary cross-sectional view, partially schematic, of an engine valve timing control system according to the invention;
FIG. 2 is an exemplary cam profile diagram for a cam according to the invention;
FIG. 3 is a cross-sectional view of an alternative embodiment of a valve timing control system in an overhead cam engine;
FIG. 4 is a cross-sectional view downward from the line 4--4 of FIG. 3; and
FIG. 5 is a cross-sectional view of a valve timing control system according to the invention using a shared solenoid valve.
DETAILED DESCRIPTION OF THE INVENTION
Referring first to FIG. 1 of the drawings in detail, numeral 10 generally indicates an engine having a first embodiment of valve timing control system according to the invention. Engine 10 rotatably carries a camshaft 12 having a cam 14 including a lobe 16 extending outward from the base circle 18 of the cam. The lobe 16 includes a lift profile 20, a valve seating ramp 22, and a return profile 24 to be subsequently more fully discussed.
Above the camshaft 12, the engine further includes a cylinder head valve gallery 26 including several bores 28 only one of which is shown. The valve gallery 26 acts as the housing for a valve actuator in each bore, each actuator including a follower piston 30 and an actuator piston 32. The pistons are axially aligned and reciprocably mounted within their respective bore 28 and are biased apart by a spring 34. Between the pistons there is defined an enclosed fluid chamber 36. Chamber 36 is filled with hydraulic fluid (generally engine oil) through a fill port 38 supplied by a pump 40 from a sump 42 through a check valve 44 that prevents reverse flow from the fill port 38. A drain port 46 also intersects the bore 28 and is connected externally with a solenoid valve 48 controlled by an electronic control unit (ECU) 50 and having an outlet connected with the sump 42.
Actuator piston 32 connects, through means such as a rocker arm not shown, with an engine valve, not shown, for actuating the valve in conventional fashion through reciprocation of the actuator piston 32 in the bore 28. In FIG. 1, piston 32 is shown in the position in which the engine valve is fully seated. In this position, the piston 32 closes the drain port 46 and prevents the escape of hydraulic fluid from the chamber 36 through the port 46.
The follower piston 30, in the embodiment shown, carries a follower roller 52 which engages the cam 14 for imparting the motion thereof to the follower piston.
FIG. 2 illustrates diagrammatically the motion of the roller follower piston 30 when actuated by the lobe 16 of the cam as it is rotated in a clockwise direction as shown by the arrow 54 in FIG. 1. As the cam lift profile 20 engages the roller 52, the piston 30 is raised along the lift curve 20' of FIG. 2 to the highest point on the lift curve shown at 0° in FIG. 2. Thereafter the piston 30 is lowered slowly by the valve seating ramp 22 along the curve 22' of FIG. 2, which represents a constant velocity seating ramp having a constant slope. At the end of the ramp 22, the roller reaches the cam return profile 24 which lowers the piston 30 along the curve 24' back to the base circle 18 indicated by the zero lift line. A dashed line 56 indicates the return profile of a conventional cam for returning the cam follower to the base circle 18. A second dashed line 58 illustrates the minimum valve opening and earliest closing of the valve, and a third dashed line 60 represents the maximum valve opening and latest closing of the valve.
In operation, when the solenoid valve 48 is closed and the camshaft is rotating clockwise, the fluid chamber 36 is filled with fluid by the pump 40 when the follower piston 30 is riding on the base circle 18 of the cam. As the lobe 16 reaches the follower, roller 52 forces the piston 30 to move along the line 20', 22', and 24' of FIG. 2. Since the fluid in chamber 36 cannot escape when the solenoid valve is closed, the actuator piston 32 is also raised along the lift profile 20' to the maximum lift point at zero cam degrees. Shortly after this point, or prior thereto, the ECU 50 opens the solenoid valve 48, allowing fluid in the chamber 36 to escape through the drain port 46 to the sump 42. During this action, the conventional valve spring, not shown, closes the engine valve at a rate permitted by the discharge of fluid through the drain port 46 and solenoid valve 48, a rate shown, for example, by the dashed line 60 of FIG. 2.
When the actuator piston 32 moves downward near to the point of valve seating, the piston 32 closes drain port 46 so that further discharge of fluid through the port is cut off. Thereafter, when the follower roller 52 is riding down the, preferably constant, slope of the seating ramp 22 of the cam lobe, the valve is closed slowly by the downward motion of the follower piston 30 which is equaled by motion of the actuator piston 32, moving the valve to the fully seated position at a rate determined by the slope of seating ramp 22 of the cam. After the valve is seated, subsequent downward movement of the follower piston 30 along the ramp 22 and the return profile 24 to the base circle 18 allows refilling of the chamber 36 with fluid through the fill port 38 in preparation for the next valve actuating event.
FIGS. 3 and 4 of the drawings illustrate an alternative embodiment of lost motion actuator and valve timing control which functions generally in a manner similar to the embodiment previously described but is arranged primarily for overhead cam engines. In this embodiment, the engine 62 carries an overhead camshaft having a cam 64 similar to cam 14 of the first described embodiment. Below the cam 64, a camshaft lifter gallery 66 of an engine cylinder head includes a bore 68 in which is mounted a cylindrical actuator housing 70. The housing 70 includes an annular rim 72 fixedly secured in the bore 68 and a reduced diameter cylinder portion 74 extending upwardly from the rim and having external and internal cylinder surfaces 76, 78, respectively. The internal surface 78 extends through the rim so that it is open on both the upper and lower ends.
A follower piston 80 is reciprocably mounted upon the external cylindrical surface 76 and extends thereabove into engagement with the cam 64. An actuator piston 82 is reciprocably received within the internal cylindrical surface 78 and directly engages a valve 84 of the engine which is conventionally urged in a seating direction by a valve spring 86. Between the pistons 80, 82, there is formed a fluid chamber 88. A spring 90 in the chamber acts against the pistons 80, 82 and urges them against the cam and the valve respectively. A fill passage 92 in the actuator housing connects at all times with the chamber 88 and with an oil supply line 94 in the lifter gallery 66 through which engine oil pressure is supplied through a check valve 96 to the chamber 88. Housing 70 also includes a drain passage 98 that connects through the lifter gallery with a solenoid valve, not shown, and extends inward to the internal surface 78 and upwardly therein to an end point 100 located below the upper end of the internal surface 78 of the associated cylinder portion 74.
Operation of this embodiment (FIGS. 3, 4) of the invention is similar to that previously described with certain exceptions. Since the follower piston 80 has a larger internal diameter exposed to chamber 88 than does the actuator piston 82, the motion of the follower piston 80 is multiplied by the area ratio to increase the follower piston motion. Thus the lift of the cam lobe on cam 64 may be made smaller than in the first described embodiment where no multiplication ratio of cam motion is present. This provides for a more compact cam and actuator structure which is of particular importance in overhead cam engines but may be desirable in other applications as well.
As shown in FIG. 3, the cam is in the process of opening the partially open valve 84. When the solenoid valve, not shown, is open, oil is drained from the chamber 88 through passage 98, allowing the valve to move toward closing until the actuator piston 82 rises to the end point 100 where flow through the passage 98 is cut off. Thereafter, as in the previous embodiment, the valve moves the remaining small amount to its closed position under control of the constant velocity seating ramp of the cam 64 so that valve seating motion is controlled directly by the cam through the actuator pistons 80, 82 with the hydraulic chamber 88 acting as a solid link.
Although the form of the structure shown in FIGS. 3 and 4 is such as to mount the piston 80 on the external surface 76 of housing 70, it should be recognized that the piston 80 could be arranged to reciprocate in sealing engagement with the bore 68 instead of the housing surface 76. In such a case, lifter gallery 66 would form, in effect, a portion of the housing of the actuator including the two pistons 80, 82. However, the chamber 88 would be expanded to the diameter of the bore 68 and the area of the upper piston against the chamber would be accordingly increased.
Referring now to FIG. 5 of the drawings, there is shown a novel embodiment of valve timing control system wherein a single solenoid valve is used to control the valve actuating performance of two actuators. In this embodiment, the engine 102 includes a camshaft having a pair of cams 104, 106 configured similarly to cam 14 of FIG. 1 and having their lobes positioned one half cycle, or 180°, out of phase. Below the cams, a lifter gallery 108 forms a housing for a pair of valve actuators 110 and 112 operating in internal bores 114 and 116, respectively, of the lifter gallery. Each of the actuators 110, 112 includes a follower piston 118 engaging its respective cam 104, 106 and an actuator piston 120 operatively engaging a valve, not shown, of the engine. The pistons are biased apart by springs 122 and define a fluid chamber 124 between them, each chamber being supplied with fluid through fill passages 126 provided with inlet check valves 128. Drain ports 130 connect the fluid chambers 124 with a single solenoid valve 132. Valve 132 is externally controlled, as by an ECU not shown, and includes an outlet passage 134 for returning discharged oil to the engine sump, not shown.
The drain ports 130 are positioned to open into their respective chamber 124 only when the engine valve has been opened slightly beyond its seated position by motion of piston 120 downwardly from the valve closed position in which actuator 110 is shown in FIG. 5 toward the valve open position in which actuator 112 is shown in FIG. 5. Since the cams 104, 106 are timed out of phase, at least one of the engine valves driven by the cams is closed at all times. Thus, it is apparent that one of the drain ports 130 is always closed. For example, port 130 from actuator 110 is shown closed in FIG. 5 while the corresponding port 130 to actuator 112 is open, since the valve driven by cam 106 is in the open position. Because of this alternate opening of the drain ports 130, the single solenoid valve 132 may be utilized to control both actuators 110 and 112. Opening of the solenoid valve will be effective to drain fluid from only the actuator which is in a valve open position. Concurrently, the other actuator chamber is cut off from the effects of fluid flow out of the operative chamber by reason of closure of the drain port 130 by the piston 120 of the closed valve actuator. In this way, any pressure pulses which may be present from discharging fluid from one of the actuators are prevented from affecting the other actuator due to the closing of its drain port.
While the invention has been described by reference to various specific embodiments, it should be understood that numerous changes may be made within the spirit and scope of the inventive concepts described. Accordingly, it is intended that the invention not be limited to the described embodiments, but that it have the full scope defined by the language of the following claims.
|
A simplified lost motion valve control system and method for engines combines a cam, having a seating ramp located between lift and return profiles of the cam lobe, with a simplified hydraulic actuator having follower and actuator pistons and a fluid discharge passage that is internally cut off by the actuator piston when the valve is close to its seated position. After opening of the valve by the cam through the actuator to a desired valve opening, the valve is closed by opening a solenoid valve to discharge fluid from the actuator until the valve closes to near its seated position. The valve is then seated by the actuator following the cam seating ramp. The actuator is refilled upon return of the follower piston along the cam return profile to the base circle. Exemplary embodiments of hydraulic actuators are disclosed as is a system including control of dual actuators, driven by out of phase cams, through a single solenoid valve alternately isolated by the discharge port closure of the actuator pistons.
| 5
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a game that involves directing an object at a moving target and particularly to a game in which a moving object is guided along a predetermined path that is alternately blocked and opened by a moving barrier.
2. Description of the Prior Art
Representative examples of games in which rolling balls or other moving game pieces are directed at moving targets, pockets or entryways are provided in U.S. Pat. No. 1,481,786 issued Jan. 29, 1924 to G. T. Barber, U.S. Pat. No. 1,538,449 issued May 19, 1925 to F. Schulz, and U.S. Pat. Nos. 1,567,251 and 1,656,272 issued Dec. 29, 1925 and Jan. 17, 1928, respectively, to J. Ekstein.
The U.S. Pat. No. 1,481,786 to Barber shows a game having upwardly inclined parallel alleys that are substantially tangent to the upper surface of a drum rotating about a horizontal axis. The alleys are interrupted by an arcuate portion of the drum, which has a number of spaced holes at axially spaced locations aligned with the center of each alley. The object of the game is to roll a ball up one of the inclined alleys so that it arrives at the top coincidentally with a corresponding hole in the drum. If its velocity is not too great, the ball will then drop through the hole into the drum and return to the player via a discharge chute and return alley. If the player misses one of the holes in the drum or the velocity is too great, the ball continues in its path over the top of the drum to the end of the alley, where it drops into a vertical chute connecting with the return alley.
In the game apparatus of Schulz U.S. Pat. No. 1,538,449 a ball is rolled down an inclined board having side rails that converge to a discharge passageway. A horizontal disk is mounted for rotation about a vertical axis, the edge of the disk being adjacent to the discharge passageway. The disk has spaced openings cut out of its edge, and the object of the game is to drop the ball through one of these openings when the opening is aligned with the discharge passageway from the board. The ball will then drop through a vertical chute and strike a trigger to actuate a mechanism for delivering a prize to the player. If the ball passes through the discharge passageway when a disk opening is not so aligned or at too great a velocity, the ball will pass radially across the disk into a central well.
In the earlier Ekstein U.S. Pat. No. 1,567,251, a motor-driven vertical shaft carries a spider that supports radial channels for rotation past the end of a chute. The object of the game is to roll a ball down the chute so that it arrives at the end coincidentally with one of the radial channels. If the player is successful, the ball will enter the radial channel and be deposited in a center cup; otherwise the ball will strike a baffle and be deflected into a return chute leading to a receptacle for returned balls. In an alternative embodiment, the successful shot passes from the radial channel into a vertical tube leading downward from the inner end of the channel and thence through an arcuate slot in a support base for the rotating structure to another chute leading to the receptacle for returned balls.
The second Ekstein U.S. Pat. No. 1,656,272 discloses improvements to the earlier game apparatus. These improvements include substitution of closed pockets for the radial channels and provision for oscillatory vertical motion of the outer ends of the pocket structures superimposed on their horizontal rotation. In an alternative embodiment, a vertical disk is mounted for rotation on a horizontal shaft, with the plane of the disk parallel to the direction of a discharge chute. A number of angularly spaced pockets are mounted on the disk for successive alignment with the end of the chute as the disk rotates.
In the foregoing prior art games the moving ball changes either speed or direction as the result of a successful encounter with a moving entryway or pocket. In some of them, such as the Schulz and Barber games, successful interception requires not only proper timing but also that ball velocity be below some maximum value. In none of them is the size of the entry or pocket adjustable to adapt the game to players having varying degrees of skill.
SUMMARY OF THE INVENTION
The apparatus of the present invention provides a rotating go-no go barrier for a game or toy in which a rolling ball or other moving game piece is directed in a predetermined linear path by an elongated guideway. Although adaptable to many game situations, the present invention is intended primarily to increase the educational and game value of the modular space toy disclosed in my prior U.S. Pat. No. 3,686,789, issued on Aug. 29, 1972, by adding launch or encounter window simulation to the interplanetary space travel game described in that patent.
Accordingly, it is an object of the present invention to provide a game apparatus in which a moving barrier alternately blocks and unblocks a guideway for a moving game piece.
It is another object of the invention to provide a game apparatus having a rotating barrier with an opening of selectively adjustable size for alternately preventing and permitting passage of a moving game piece along a predetermined path, the relative duration of the passage preventing and permitting periods being determined by the selected size of the opening.
Another object of the invention is to provide a pivoting target mounted in an opening of a rotating transverse barrier positioned across a guideway such that passage through the opening of a game piece moving along the guideway will cause the target to pivot from a first predetermined position to a second predetermined position.
It is still another object of the invention to provide a motor drive train for a rotating barrier to produce a constantly varying speed of rotation.
These and other objects are accomplished by a game apparatus that includes an upright stand; a guideway attached to the stand for guiding a moving game piece along a predetermined path; a movable barrier in the form of a disk having a portion cut out from its circumference; means for mounting the disk on the stand directly above the guideway for rotation about the center of the disk in a plane transverse to the direction of the predetermined path such that passage of a moving game piece along the predetermined path is prevented by the disk except when the cut out portion is aligned with the guideway.
The disk preferably is equipped with a movable shutter for selectively varying the circumferential extent of the cut out portion to vary correspondingly the relative times that the guideway is blocked and unblocked during each revolution of the disk.
The disk also preferably includes a target plaque pivotally mounted in a cut out portion of the circumference for rotation from a first position in which one face of the target plaque is presented to a game player to a second position in which the reverse face of the target plaque is presented to the player.
To prevent a game piece that did not pass the barrier from bouncing back and obstructing the guideway, the game apparatus preferably also includes a one-way barrier in front of the disk that may comprise simply a step down in the guideway, with the riser of the step serving as a barrier to trap the game piece between the riser and the face of the disk. Protrusions, such as radial flanges extending from the face of the disk, then sweep the trapped piece laterally from the guideway to clear the path for the next game piece.
Means for rotating the disk may include a handcrank or preferably an electric motor driving through gear trains to provide either constant speed rotation or, optionally, continuously variable rotation speeds.
These and other features and objects of the invention will be apparent from the following description of preferred embodiments in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a rear perspective view of a rotating disk toy according to the invention as adapted to simulate an encounter window in combination with a modular space toy.
FIG. 2 is a front view of the rotating disk toy of FIG. 1.
FIG. 3 is a section view of the rotating disk toy of FIG. 2 taken along line 3--3.
FIG. 4 is an enlarged perspective view of a guideway attachment support for the rotating disk toy of FIG. 2.
FIG. 5 is a partial front perspective view of the rotating disk toy of FIG. 2 illustrating the manner of mounting a sector plate shutter on the disk.
FIG. 6 is a perspective view of an alternate drive train for the motor drive shown in FIG. 3.
FIG. 7 is a radial section view of a pivoting target plaque mounted in a cut out portion of the rotating disk of FIG. 2.
FIG. 8 is a partial front view of the rotating disk of FIG. 7 showing the target plaque in a first predetermined position.
FIG. 9 is a partial front view similar to FIG. 8 but showing the target plaque in a second predetermined position.
FIG. 10 is a partial section view showing an alternate mounting arrangement for the sector plate shutter of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference has been made earlier to the particular applicability of the rotating barrier game apparatus of the present invention to simulate a launch or encounter window for interplanetary spaceship travel in conjunction with the modular space toy described in my prior U.S. Pat. No. 3,686,789. An arrangement for demonstrating such a simulation is illustrated by FIG. 1, in which conical bowls 1 and 2 and interconnecting guideway 3 are components of my prior modular space toy. The rotating disk toy of the present invention is designated generally by reference numeral 4.
In the game arrangement of FIG. 1, bowl 1 simulates a launching system for a spaceship, represented by moving ball 5. The flat bottom of bowl 1 represents a planet, such as Earth, and the ball is set to rotating counterclockwise around the inside of the bowl until it reaches "escape" velocity and enters tangential passageway 6 at the top of the bowl. From passageway 6, the ball enters interconnecting guideway 3 and travels toward the second bowl 2, representing Mars as shown in the diagram.
In order for a spaceship from Earth to enter landing orbit around Mars, it must lead the target because of the relative movement between Mars and Earth from the time of launch to the time of encounter. Rotating disk toy 4 provides the simulation for this maneuver.
Toy 4 includes an upright stand having a base 7 supporting a vertical panel 8. Panel 8 faces bowl 1 and has a cut out opening 10 for guideway 3 to pass through the panel. Above the guideway is a movable barrier such as flat circular disk 9 mounted on the panel for rotation about an axis through the center of the disk, the axis being located above the guideway by a distance such that the edge of the disk clears the guideway but prevents passage of ball 5 through the opening in the panel.
Disk 9 has a notch 11 extending for a predetermined circumferential extent in the edge of the disk. Notch 11 simulates the "encounter window" or "entry corridor" for the planet Mars in the illustrated embodiment of the game. As shown in FIG. 1, notch 11 must coincide with panel opening 10 to permit passage of ball 5 into "orbit" around Mars, as defined by the walls of bowl 2, with Mars at the base of the bowl. Assuming clockwise rotation of disk 9, as shown by the arrow, it is clear that the position of notch 11 must be at some point ahead of opening 10 at the time that the ball is "launched" from bowl 1. In the diagram, for example, notch 11 is approximately at the 2 o'clock position at the time of launch. The notch then rotates to the 6 o'clock position in the time that it takes ball 5 to travel along guideway 3 to the rotating disk. Thus, the combination of the rotating disk apparatus with the modular space toy of my prior U.S. Pat. No. 3,686,789 contributes substantially to increased educational value as well as enjoyment of the interplanetary space travel game.
The details and additional features of the preferred embodiment of the rotating disk apparatus are shown more clearly in FIGS. 2 through 5. As shown in these figures, disk 9 is attached to a shaft 12 that is journalled for rotation in panel 8. The forward end of shaft 12 is threaded for a nut 13, and the rear end of the shaft carries a drive gear 14. An electric motor 15 turns the disk through a pinion 16, a ring gear 17, a secondary shaft 18, and a second pinion 19 that engages the drive gear 14. Motor 15 is powered by batteries 20 installed on the rear of base 7 and connected to the motor through wires 21, 22 and a switch 23 that is located at any convenient position.
As an alternative to the electric motor drive, the disk can be driven by a simple handcrank 24 attached to an extension 25 of shaft 12 (see FIG. 3). To protect the fingers of children, the drive mechanism is surrounded by a cover 26.
Referring to FIG. 4, there is shown a preferred arrangement for attaching the guideway to either side of the panel. This arrangement comprises a guideway bracket 27, preferably made of molded plastic. The bracket is in the form of a horizontal guideway portion 28 with a dependent transverse flange 29 for attachment to panel 8 by means of screws 30. A longitudinal triangular gusset 31 provides a rigid connection between the bottom of guideway 28 and flange 29 and also supports a horizontal tongue 32 extending forward for frictional engagement with a mating groove formed by angle members 33 and 34 molded in the underside of a plastic channel member 35 that defines the travel path for ball 5 from bowl 1. A similar tongue 36 extends from the rear of guideway bracket 27 for frictional engagement with mating channel member 37 that continues the ball pathway to bowl 2.
An important feature of guideway bracket 27 is the provision of a one-way barrier to prevent bounce back of ball 5 into channel section 35 in the event that the ball fails to successfully pass through the notch in the rotating disk. This one-way barrier consists of a transverse riser 38 extending above the floor of guideway 28 at the forward end, with tongue 32 leading into the top of the riser. Thus, if the player miscalculates the necessary lead required in launching ball 5, the ball will enter guideway 28 when the notch of disk 9 is not aligned with the guideway. The ball will then strike the face of the disk and will reflect backward and downward into contact with riser 38, as indicated by the arrows.
In order to remove a ball trapped by barrier riser 38 from the guideway, rotary disk 9 carries at least one protrusion, in the form of a short radial flange 39, extending from its face adjacent to the edge of the disk. A portion of the left hand wall 40 of guideway 28 is removed so that as the radial disk rotates in the clockwise direction, flange 39 swings down and knocks the ball off the guideway so that it will not interfere with the next simulated spaceship to be launched.
Referring next to FIG. 5, a feature of the preferred disk embodiment is shown as a movable shutter in the form of a sector plate 41 having a radius equal to the radius of the disk. The shutter plate is pivotally mounted on shaft 12 in overlapping relation against the disk, with nut 13 holding the shutter in frictional engagement with the disk. Rotation of the shutter with respect to the disk against the frictional force permits adjustment of the effective circumferential extent of notch 11 by preselected increments, as measured by graduations 42.
Adjustment of sector plate 41 to uncover the complete extent of notch 11 (which is shown as approximately 90° in the illustrated embodiment) adapts the game for use by even very young children and simulates travel to a planet having a very wide entry corridor. On the other hand, adjusting the shutter to a narrow opening for the notch provides a challenge to even an adult player. In this way, the game can be adapted to be played by a number of persons of widely varying age and skills.
The drive train illustrated in FIG. 3 provides a constant angular velocity of the disk, preferably about 10-16 rpm. FIG. 6 illustrates an alternative embodiment in which a pair of meshing off-center gears 43 and 44 replace gears 16 and 17 in FIG. 3. As is well known, a pair of such off-center gears will provide a continuously varying output speed to shaft 18 from a constant input speed as delivered by the motor. Such continuously varying rotation speed more closely simulates the velocity of planets in an elliptical orbit and increases the challenge to the player's skill in properly choosing the ball release time.
Referring next to FIGS. 7-9, disk 9 can optionally be fitted with a target plaque 45 pivotally mounted in a notch 46 in the edge of the disk on axles 47 nad 48. The axis of axles 47, 48 intersects the sides of notch 46 at approximately their midpoints to permit the target plaque to flip from a first position in which one face of the plaque is exposed (FIG. 8) to a second position in which the reverse face is exposed (FIG. 9).
The target plaque is held in the first position by an offset lip 49 which abuts the inner edge of the notch and carries a piece of iron 50 for mating contact with a magnet 51 embedded in the disk. When the outer edge of the target is struck by a ball 5 with sufficient impact to disengage the piece of iron from the magnet, the target will flip to the second position shown by broken lines in FIG. 7. The target is held in the second position by a similar magnetic catch until it is reset by the player.
The exposed face of the target plaque in the first position may carry an illustration of an "enemy" space ship, as shown in FIG. 8, to increase the excitement of the game. When a hit is scored, the target plaque flips to reveal the enemy spaceship in flames (FIG. 9).
The optional target embodiment may be used in place of or, preferably, in addition to the notch and shutter combination. In the latter case the target notch can be spaced circumferentially from the "encounter window" notch.
FIG. 10 shows an alternative arrangement for permitting selective positive adjustment of the sector plate shutter 41 without loosening and retightening nut 13. In this arrangement, the back of the sector plate has a protrusion 52 that can selectively engage any one of a plurality of mating angularly spaced indentations 53 in the face of disk 9. A coil spring 54 positioned between the nut and the face of the sector plate allows the edge of the plate to be lifted so that protrusion 52 is clear of indentation 53, and the shutter can be rotated to another selected angular position without disturbing the nut on the shaft.
Although the preferred embodiments of the rotating disk toy of the present invention have been illustrated and described, it will be apparent that many variations in constructional details can be employed without departing from the scope of the invention.
Furthermore, although the present invention has been demonstrated as being particularly suitable for use in an interplanetary space travel game in conjunction with the modular space toy of my U.S. Pat. No. 3,686,789, it will also be apparent that is has broad application in any type of game in which a gamepiece is projected or propelled along a guideway in a predetermined path.
|
A game for simulating launching and landing of spacecraft. An elongated channel attached to an upright stand defines a predetermined path for a moving game piece. A notched rotating disk mounted on the stand transversely above the channel prevents passage of the game piece except when the notch coincides with the channel. The effective circumferential extent of the notch can be selectively varied by a movable shutter for simulating approach corridors of varying widths. Alternatively, a target plaque pivotally mounted in the notch rotates from a first to a second position if struck by a simulated missile. Game pieces that fail to pass the rotating disk are prevented from bouncing back into the approach channel by a one-way barrier and are then removed from the channel by flanges protruding from the face of the disk. The disk may be rotated with constant angular velocity or with continuously varying velocity by means of off-center gears.
| 0
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a Continuation of U.S. Ser. No. 13/415,415, filed Mar. 8, 2012 which claims the benefit of prior provisional application, U.S. Ser. No. 61/069,046, filed Mar. 12, 2008, and is a continuation of U.S. Ser. No. 12/380,391, filed Feb. 26, 2009, all of which are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention is directed to hydroswellable (or water-swellable) absorbable and non-absorbable aliphatic, segmented polyurethanes and polyurethane-ureas, which can undergo swelling when placed in the biological environment manifested through an at least 3 percent increase in volume by virtue of having a highly hydrophilic polyalkylene oxide as an inherent part of their segmented chain molecules. By varying the type and fraction of the different segments constituting the copolymers, their pharmaceutical and biomedical applications as non-absorbable and absorbable materials entail their use in carriers for the controlled release of bioactive agents, rheological modifiers of absorbable and non-absorbable cyanoacrylate tissue adhesives, synthetic cartilage-like materials, and scaffolds for tissue engineering cartilage tissues.
BACKGROUND OF THE INVENTION
[0003] Polyurethanes represent a main class of synthetic elastomers applied for long-term, medical implants as they present tunable chemical properties, excellent mechanical properties, good blood compatibility, and also can be designed to degrade in biological environments [A. Rechichi et al., J. Biomed. Mater. Res., 84-A, 847 (2008)]. More specifically, polyether-urethane (PEU) and polyether-urethane-urea (PEUU) elastomers have long been considered ideal for use in many implanted devices, in spite of occasionally cited drawbacks [M n A. Schubert et al., J. Biomed. Mater. Res., 35, 319 (1997); B. Ward et al., J. Biomed. Mater. Res., 77-A, 380 (2008)]. Of the cited drawbacks are those associated with (1) the generation of aromatic diamines, which are considered to be toxic upon degradation of segmented copolymers made using aromatic diisocyanates for interlinking; (2) chain degradation due to oxidation or radiation degradation of the polyether component of segmented copolymers, and particularly those which encounter frequent mechanical stresses in the biological environment; and (3) chemical degradation in chemically and mechanically hostile biological environments of the urethane links of segmented copolymers and particularly those comprising reactive aromatic urethane linkages.
[0004] Liquid solventless, complex polymeric compositions, which thermoset at ambient temperatures through additional polymerization of a two-component system, wherein the first component comprises amine or acrylate-terminated polyurethanes or polyurethane-ureas and the second component comprises di- or polyacrylates have been described in U.S. Pat. No. 4,742,147. However, the prior art is virtually silent on self-standing PEU and PEUU liquid solventless compositions for use in pharmaceutical formulations and/or medical devices. Similarly, the prior art on polyether-urethanes is practically silent on hydroswellable (or water-swellable) systems, in spite of the fact that it covered elastomeric, segmented, hydrophilic polyether-urethane-based, lubricious coating compositions based on aromatic diisocyanate and polyethylene glycol (U.S. Pat. No. 4,990,357)—it did not suggest a self-standing material for medical device applications.
[0005] Collective analysis of the prior art on PEU and PEUU as discussed above regarding the drawbacks of the disclosed systems, absence of self-standing liquid and hydroswellable copolymers, and recognition of the need for new materials exhibiting properties that cannot be met by those of the prior art, provided a strong incentive to explore the synthesis and evaluation of the PEU and PEUU systems subject of this invention, which are structurally tailored for their effective use in existing and new applications.
SUMMARY OF THE INVENTION
[0006] The present invention is directed to different types of hydroswellable (or water-swellable) polyurethanes and polyurethane-ureas.
[0007] A specific aspect of the invention describes a hydroswellable, segmented, aliphatic polyurethane comprising polyoxyalkylene chains, covalently linked to polyalkylene carbonate chains, which are interlinked with aliphatic urethane segments, the composition exhibiting an at least 3 percent increase in volume when placed in the biological environment, wherein the polyoxyalkylene glycol chains comprise at least one type of oxyalkylene sequences selected from the group represented by oxyethylene, oxypropylene, oxytrimethylene, and oxytetramethylene repeat units and the alkylene carbonate chains are trimethylene carbonate sequences, and wherein the urethane segments are derived from at least one diisocyanate selected from the group represented by tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, lysine-derived diisocyanate, and cyclohexane bis-(methylene isocyanate). Meanwhile, the polyurethane is made by reacting a liquid polyoxylene alkylene glycol comprising oxyethylene or a combination of oxyethylene and oxypropylene sequences that are end-grafted with trimethylene carbonate wherein the resulting product is interlinked with 1,6-hexane diisocyanate, and wherein the liquid polyalkylene glycol is a polyethylene glycol having, preferably, a molecular weight of about 400-500 Da. From a pharmaceutical application perspective, the polyurethanes can be used as vehicles for a controlled release formulation of at least one bioactive agent selected from the group of agents known to exhibit anti-inflammatory, anesthetic, cell growth promoting, antimicrobial, antiviral, and antineoplastic activities. In a specific pharmaceutical application, the controlled release formulation comprises at least one antimicrobial agent after treating periodontitis or bone infection selected from the group represented by doxycycline, gentamicin, vancomycin, tobramycin, clindamycin, and mitomycin and the periodontal formulation may include absorbable microparticles made of acid-terminated glycolide-based polyester and a liquid excipient such as a liquid polyethylene glycol and an alkylated or acylated derivative thereof. In a second group of pharmaceutical applications, the controlled release formulation comprises a liquid polyethylene glycol or an alkylated or acylated derivative thereof as an excipient and at least one bioactive agent selected from the group represented by paclitaxel, carboplatin, miconazole, leflunamide, ciprofloxacin, and a recombinant protein for treating breast or ovarian cancer in humans or animals. Additionally, for tissue repair applications, the polyurethane can be admixed with one or more cyanoacrylate monomer for use as a rheological modifier of tissue adhesives, wherein the one or more cyanoacrylate monomer is part of an absorbable or non-absorbable tissue adhesive formulation comprising stabilizers against premature polymerization, free radically and anionically, and at least one monomer selected from the group represented by ethyl-, butyl-, isobutyl-, methoxypropyl-, methoxyethyl-, and methoxybutyl cyanoacrylate.
[0008] Another specific aspect of the present invention deals with a hydroswellable, segmented, aliphatic polyurethane-urea comprising polyoxyalkylene chains covalently interlinked with polyalkylene urethane segments, which are further interlinked with aliphatic urea chain segments, the composition exhibiting at least 5 percent increase in volume when placed in the biological environment, wherein the polyalkylene glycol chains comprise at least one type of oxyalkylene sequences selected from the group represented by oxyethylene, oxypropylene, oxytrimethylene, and oxytetramethylene repeat units and the urethane segments are derived from at least one diisocyanate selected from the group represented by hexamethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, 1,4 cyclohexane diisocyanate, lysine-derived diisocyanate, and cyclohexane bis(methylene isocyanate) and wherein the resulting polyoxyalkylene urethane molecules having at least one isocyanate terminal group are chain-extended with an alkylene diamine selected from the group represented by ethylene-, trimethylene, tetramethylene-, hexamethylene-, and octamethylene-diamine, thus forming polyetherurethane-urea segmented chains.
[0009] A clinically important aspect of the invention deals with a hydroswellable, segmented, aliphatic polyurethane-urea comprising polyoxyalkylene chains covalently interlinked with polyalkylene urethane segments, which are further interlinked with aliphatic urea chain segments, the composition exhibiting at least 5 percent increase in volume when placed in the biological environment, wherein the polyurethane-urea (1) can be chemically crosslinked, wherein the crosslinking is achieved using an alkylene diisocyanate; (2) can exhibit microporosity with a practically continuous cellular structure; (3) can comprise at least one covalently bonded aromatic group to stabilize the chain against radiation and oxidation degradation; and/or (4) can be used as an artificial cartilage for restoring the function of diseased or defective articulating joints in humans and animals.
[0010] An important aspect of this invention deals with a hydroswellable, segmented, aliphatic polyurethane comprising polyoxyalkylene chains covalently linked to polyester or polyester-carbonate chain segments, interlinked with aliphatic urethane segments, the composition exhibiting at least 5 percent increase in volume when placed in the biological environment, wherein the polyester or polyester-carbonate chain segments are derived from at least one cyclic monomer selected from the group represented by ε-caprolactone, trimethylene carbonate, p-dioxanone, 1,5-dioxepan-2-one, l-lactide, dl-lactide, glycolide, and a morpholinedione. Meanwhile, the polyurethane can exhibit microporosity with practically continuous cellular structure for use as an absorbable scaffold or part thereof for cartilage tissue engineering, with or without the aid of a cell growth promoting agent therein.
[0011] For prolonged effective device performance, the present invention is directed to a hydroswellable, segmented, aliphatic polyurethane-urea comprising a combination of linear functionalized polysiloxane and polyoxyalkylene chains interlinked with polyalkylene urethane segments, which are further interlinked with aliphatic urea chain segments, the composition exhibiting at least 5 percent increase in volume when placed in the biological environment, wherein the polyoxyalkylene chain comprises at least one type of oxyalkylene sequences selected from the group represented by oxyethylene, oxypropylene, oxytrimethylene, and oxytetramethylene repeat units and the functionalized polysiloxane is derived from bis-hydroxyalkyl-terminated polysiloxane comprising at least dimethoxysiloxane internal sequences and two hydroxyalkyl or aminoalkyl terminals and further wherein the urethane segments are derived from at least one diisocyanate selected from the group represented by hexamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, 1,4 cyclohexane diisocyanate, lysine-derived diisocyanate, and cyclohexane bis(methylene isocyanate) and wherein the resulting polyoxyalkylene urethane molecules having at least one isocyanate terminal group are further chain-extended with an alkylene diamine selected from the group represented by ethylene-, trimethylene, tetramethylene-, hexamethylene- and octamethylene-diamine, thus forming polyetherurethane-urea segmented chains, wherein the polyurethane-urea (1) can be chemically crosslinked wherein the crosslinking is achieved using an alkylene diisocyanate; (2) can exhibit microporosity with a practically continuous cellular structure; (3) can comprise at least one covalently bonded aromatic group to stabilize the chain against radiation and oxidation degradation; and/or (4) can be used as an artificial cartilage for restoring the function of diseased or defective articulating joints in humans and animals.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0012] The present invention is generally directed to the tailored synthesis of the following families of hydroswellable polymers. The term “hydroswellable” is intended to indicate that the polymers swell and increase in volume in the presence of water.
[0013] (1) Relatively slow-absorbing. segmented polvether-carbonate-urethanes (PECU) as vehicles for the controlled release of bioactive agents including those known to exhibit or unexpectedly exhibit antimicrobial, microbicidal, antineoplastic, and antiviral activities wherein the typical PECUs (a) exhibit <20 percent or no solubility in water, (b) are made to be liquids at about 50° C.; (c) have a weight average molecular weight exceeding 10 kDa; (d) swell in an aqueous environment leading to an increase of volume of at least 3 percent; and (e) are miscible in water-soluble, low viscosity liquid excipients, such as polyethylene glycol 400, to facilitate their use as injectable formulations that undergo gel-formation when introduced to aqueous biological sites—the ratio of the PECU to the excipient can be modulated in concert with the active agent solubility, its intended release site, and preferred release rate.
[0014] (2) The PECUs of Item 1 as rheology modifiers of cyanoacrvlate-based tissue adhesive formulations wherein (a) the PECU is used to increase the viscosity of the uncured tissue adhesive; (b) render the cured tissue adhesive more compliant and able to conform with the biological site—this is achieved by decreasing the cured adhesive modulus due to the presence of the low modulus PECU at concentrations of at least one weight percent; (c) the cyanoacrylate tissue adhesive comprises at least one monomer selected from the group represented by ethyl-, n-butyl-, isobutyl-, methoxypropyl-, ethoxypropyl-, methoxybutyl-, and octyl-cyanoacrylate; and (d) the cyanoacrylate tissue adhesive contains at least one stabilizer to prevent premature polymerization by an anionic and free radical mechanism-typical examples of these are pyrophosphoric acid and butylated hydroxyl anisole for stabilization against anionic and free radical polymerization, respectively.
[0015] (3) Relatively fast-absorbing, segmented aliphatic polvether-ester urethanes (PEEU) and polyether-carbonate-ester urethanes (PECEU) as vehicles for the controlled release of bioactive agents including those known to exhibit or unexpectedly exhibit antimicrobial, microbicidal, antiviral, and antineoplastic activities wherein the typical PEEUs and PECEUs (a) exhibit limited (<20 percent) or no solubility in water; (b) are made to be liquids at about 50° C.; (c) have a weight average molecular weight exceeding 10 kDa; (d) swell in an aqueous environment leading to an increase of volume of at least 3 percent; and (e) are miscible in water-soluble, low viscosity liquid excipients, such as polyethylene glycol 400 and an alkylated or acylated derivative thereof, to facilitate their use as injectable formulations that undergo gel-formation when introduced to aqueous biological sites—the ratio of the PECU to the excipient can be modulated in concert with the active agent solubility, its intended release site, and preferred release rate.
[0016] (4) The PEEUs and PECEUs of Item 3 as rheology modifiers of absorbable cyanoacrvlate-based tissue adhesive formulations wherein (a) the PEEU or PECEU is used to increase the viscosity of the uncured tissue adhesive; (b) render the cured tissue adhesive more compliant and able to conform with the biological site—this is achieved by decreasing the cured adhesive modulus due to the presence of the low modulus PEEU or PECEU at concentrations of at least one weight percent; (c) the cyanoacrylate tissue adhesive comprises an alkoxyalkyl cyanoacrylate, such as methoxypropyl cyanoacrylate or a mixture of an alkoxyalkyl cyanoacrylate and an alkyl cyanoacrylate, such as ethyl cyanoacrylate; and (d) the cyanoacrylate tissue adhesive contains at least one stabilizer to prevent premature polymerization by an anionic and free radical mechanism—typical examples of these are pyrophosphoric acid and butylated hydroxyl anisole for stabilization against anionic and free radical polymerization, respectively.
[0017] (5) Essentially biostable, non-absorbable, segmented, aliphatic polyether urethane-ureas (PEUU) as flexible, solid, linear or chemically crosslinked polymers for use primarily as cartilage-like materials, which undergo swelling and deswelling upon cyclic application of compressive force for prolonged periods, while practically maintaining their initial properties, wherein the typical PEUUs (a) exhibit limited (<5 percent) or no solubility in water; (b) can be fabricated into films, sheets or caps for articulating bones in humans or animals with essentially no display of first order thermal transitions and exhibiting ultimate elongation exceeding 200 percent, reversible elongation of >10 percent and an at least 5 percent increase in volume when immersed in water for less than two hours; (c) have a molecular weight corresponding to an inherent viscosity of more than unity using hexafluoro-isopropyl alcohol (HFIP) as a solvent when present as linear molecular chains; and (d) can be fabricated into different desirable forms or geometries by solution casting.
[0018] (6) Highly biostable, non-absorbable. segmented, aliphatic PEUU as in Item 5 comprising a polysiloxane (e.g., poly dimethyl siloxane segment) to improve its oxidation stability in the biological environment.
[0019] (7) Highly biostable, non-absorbable, segmented, aliphatic PEUU as in Item 5 comprising a covalently bonded chemical entity capable of minimizing or eliminating radiation during radiation sterilization, and oxidative degradation when placed in the biological environment. These radiation and oxidation stabilizers can be in the form of polymerizable (as in diols) derivatives of hydroxyl aromatic compounds or low molecular polymers comprising oxy-aromatic groups and hydroxyl end-groups. Such simple or polymeric diols can be mixed with the polyether diol prior to end-grafting with other monomers and interlinking with diisocyanate.
[0020] (8) Absorbable, segmented, aliphatic polyether-ester urethane (APEEU) and polyether-ester-carbonate urethane (APEECU) as scaffolds for cartilage tissue engineering wherein the typical APEEUs and APEECUs (a) comprise polyoxyalkylene chains (such as those derived from polyethylene glycol and block or random copolymers of ethylene oxide and propylene oxide) covalently linked to polyester or polyester-carbonate segments (derived from at least one monomer selected from the group represented by trimethylene carbonate, ε-caprolactone, lactide, glycolide, p-dioxanone, 1,5-dioxepan-2-one, and a morpholinedione) and interlinked with aliphatic urethane segments derived from 1,6 hexamethylene-, 1-4 cyclohexane-, cyclohexane-bis-methylene-, 1,8 octamethylene- or lysine-derived diisocyanate; (b) display at least 5 percent increase in volume due to swelling, when placed in the biological environment; (c) have a microporous structure with average pore size ranging between about 20 and 400 micron and practically continuous cell structure; and (d) are suitable for use as an absorbable scaffold for cartilage tissue engineering wherein the scaffold may contain at least one bioactive agent which may include at least one cell growth promoter.
[0021] From a clinical perspective, compositions and formulations or devices thereof subject of the present invention can be used in a broad-range of applications including (1) injectable gel-forming liquid formulations for the controlled delivery of bioactive agents for treating periodontitis, nail infection, bone infection, a variety of bacterial and fungal infections, and different forms of cancers; (2) in situ-forming, extrudable luminal liner for the controlled drug delivery at the luminal wall of vaginal canals and blood vessels; (3) a rheology modifier for essentially non-absorbable and absorbable cyanoacrylate-based tissue adhesive formulations; (4) cartilage-like covers to protect defective or diseased articulating joints; and (5) an absorbable scaffold for cartilage and soft tissue engineering.
[0022] Further illustrations of the present invention are provided by the following examples:
Example 1
Synthesis and Characterization of a Typical Polyether-carbonate-urethane, P-1
[0023] For an initial charge, poly(ethylene glycol) (M n =400 Da) (0.15 moles) and tin(II) 2-ethyl hexanoate (3.53×10 −4 moles) were added to a 500 mL, 3-neck, round-bottom flask equipped with a PTFE coated magnetic stir bar. The contents were heated to 70° C. and allowed to stir for 10 minutes. For a second charge, trimethylene carbonate (0.882 moles) was added and the contents were heated to 135° C. Conditions were maintained until practically complete monomer conversion was achieved. The magnetic stir bar was removed and replaced by a stainless steel mechanical stirrer. The polymer was cooled to room temperature. For a third charge, 1,6-diisocyanatohexane (0.12 moles) was added and the contents were stirred until complete mixing was achieved. The contents were stirred and heated to 100° C. Conditions were maintained for 1.25 hours. The polymer was allowed to cool to room temperature and then dissolved in an equal part of tetrahydrofuran. The polymer solution was treated with 5 mL of 2-propanol at 55° C. then precipitated in cold water. The purified polymer was isolated and dried to a constant weight at 55° C. on a rotary evaporator. The purified polymer was characterized for molecular weight by GPC using tetrahydrofuran as the mobile phase which resulted in an M n , M w , M p , and PDI of 11 kDa, 19 kDa, 18 kDa, and 1.7 respectively. Identity and composition were confirmed by FT-IR and NMR, respectively.
Example 2
Synthesis and Characterization of Liquid Polyether-Ester-Urethane
General Method
[0024] For an initial charge, poly(ethylene glycol) (M n =400 Da) and tin(II) 2-ethyl hexanoate were added to a 500 mL, 3-neck, round-bottom flask equipped with a PTFE coated magnetic stir bar. The contents were heated to 70° C. and allowed to stir for 10 minutes. For a second charge, dl-lactide and glycolide were added and the contents were heated to 135° C. Conditions were maintained until practically complete monomer conversion was achieved. The magnetic stir bar was removed and replaced with a stainless steel mechanical stirrer. The polymer was cooled to room temperature. For a third charge, 1,6-diisocyanatohexane was added and the contents were stirred until complete mixing was achieved. The contents were stirred and heated to 100° C. Conditions were maintained for 1.25 hours. The polymer was allowed to cool to room temperature and then dissolved in an equal part of tetrahydrofuran. The polymer solution was treated with 5 mL of 2-propanol at 55° C. then precipitated in cold water. The purified polymer was dried to a constant weight at 55° C. on a rotary evaporator. The purified polymer was characterized for molecular weight by GPC using tetrahydrofuran as the mobile phase. Identity and composition were confirmed by FT-IR and NMR, respectively.
Example 3
Synthesis and Characterization of Typical Polyether-Ester-Urethanes Using the General Method of Example 2, P-2, P-3, and P-4
[0025] Polyether-ester-urethanes P-2, P-3, and P-4 were prepared using the method of Example 2 with 0.15, 2.225, 0.15 moles of polyethylene glycol (M n =400 Da), 2.60×10 −4 , 3.18×10 −4 , 2.60×10 −4 moles of tin(II) 2-ethyl hexanoate, 0.52, 0.64, 0.52 moles of dl-lactide, 0.13, 0.16, 0.13 moles of glycolide, and 0.18, 0.18, 0.12 moles of 1,6-diisocyanatohexane, respectively. Polymers P-2, P-3, and P-4 were characterized for molecular weight by GPC using tetrahydrofuran as the mobile phase which resulted in M n of 11, 9, and 9 kDa, M w of 20, 14, and 15 kDa, Mp of 20, 12, 14, kDa, and PDI of 1.9, 1.6, and 1.6, respectively. Identity and composition were confirmed by FT-IR and NMR, respectively.
Example 4
Synthesis and Characterization of Typical Polyether-Ester-Urethanes Using the General Method of Example 2, P-5 to P-8
[0026] Polyether-ester-urethanes P-5, P-6, P-7 and P-8 were prepared using the method of Example 2 with 0.15, 0.22, 0.22, 0.22 moles of polyethylene glycol (M n =400 Da), 3.53×10 −4 , 4.17×10 −4 , 4.22×10 −4 , 4.12×10 −4 moles of tin(II) 2-ethyl hexanoate, 0.88, 0.94, 1.08, and 0.80 moles of trimethylene carbonate (TMC), 0.00, 0.31, 0.19, and 0.43 moles of glycolide, and 0.12, 0.18, 0.18, and 0.18 moles of 1,6-diisocyanatohexane, respectively. Polymers P-5, P-6, P-7 and P-8 were characterized for molecular weight by GPC using tetrahydrofuran as the mobile phase which resulted in M n of 11, 10, 10, and 9 kDa, M w of 19, 14, 16, and 14 kDa, Mp of 18, 13, 15, and 14 kDa, and PDI of 1.7, 1.4, 1.6 and 1.5, respectively. Identity and composition were confirmed by FT-IR and NMR, respectively.
Example 5
Synthesis and Characterization of Acetylated Polyethylene Glycol-400 Da (PG-4A) for Use as a Diluent Liquid Excipient of P-2 to P-8
[0027] Predried polyethylene glycol having a molecular weight of about 400 Da (25.6 g) was mixed in a round-bottom flask (equipped for magnetic stirring and refluxing) under dry nitrogen atmosphere with purified acetic anhydride (22.2 g). The mixture was stirred for 1 hour at 40° C. and then at 100° C. for 3 hours. At the conclusion of the reaction, the contents of the flask were heated under reduced pressure to remove the acetic acid reaction by-product and excess acetic anhydride. The acetylated product (PG-4A) was characterized for identity by infrared spectroscopy and molecular weight by gel permeation chromatography (GPC).
Example 6
Synthesis, Characterization, and Testing of a Typical Film-Forming Polyether-Urethane-Urea, PEUU-I
[0028] Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (M n =14,600 Da, 82.5 wt % poly(ethylene glycol) (1.64×10 −3 moles) and poly(tetramethylene glycol) (M n =2,900 Da) (1.93×10 −2 moles) were added to a 500 mL glass resin kettle equipped for mechanical stirring and vacuum. The contents were dried at 140° C. under reduced pressure for 3 hours and then cooled to room temperature. N,N-Dimethylacetamide (190 mL) was added and the contents were heated to 60° C. and stirred until a homogeneous solution was obtained. The contents were cooled to room temperature and 1,6-diisocyanatohexane (3.14×10 −2 moles) was added. The contents were stirred until a homogeneous solution was obtained. Tin(II) 2-ethyl hexanoate (3.53×104 moles) in the form of a 0.2 M solution in 1,4-dioxane was added. The contents were stirred until a homogeneous solution was obtained and then heated to 100° C. under stirring conditions. Conditions were maintained for 2 hours. The contents were cooled to room temperature. Ethylene diamine (1.05×10 −2 moles) was added in the form of a 1.16 M solution in N,N-dimethylacetamide under stirring conditions. Upon gelation, the stirrer was stopped and conditions were maintained for 24 hours. The polymer was purified by subsequent extractions with water and acetone then dried to a constant weight at 45° C. under reduce pressure. The purified polymer was characterized for molecular weight by inherent viscosity in hexafluoroisopropanol which resulted in an inherent viscosity of 5.71 dL/g. Identity was confirmed by FT-IR.
Example 7
Preparation and Properties of n-Butyl Cyanoacrylate-Based Tissue Adhesive Formulation Using P-5 from Example 4 as a Rheology Modifier
[0029] This entailed mixing and characterizing the different monomer combinations and using a selected mixture to prepare a typical adhesive formulation
[0030] A pure methoxypropyl cyanoacrylate (MPC) and pure n-butyl cyanoacrylate (BC) monomers and combination thereof were characterized for their rheological properties, measured in terms of their comparative viscosity as listed Table I. Ratios of 90/10, 50/50, 20/80, and 10/90 (by weight) of MPC to butyl cyanoacrylate were mixed. Monomers were weighed in a centrifuge tube and placed on a shaker for 15 minutes. The rheological data of the resulting compositions are summarized in described in Table I.
[0000]
TABLE 1
Cyanoacrylate Monomer Compositions and Their Rheological Data a
Monomer Ratios
Monomer Composition
Comparative Viscosity (s)
100
BC
3.30 ± 0.06
10:90
MPC:BC
3.42 ± 0.06
20:80
MPC:BC
3.55 ± 0.10
50:50
MPC:BC
4.23 ± 0.14
90:10
MPC:BC
5.16 ± 0.17
100
MPC
6.15 ± 0.36
a Measured in terms of time (in seconds) to collect 0.3 mL of liquid adhesive, transferring vertically by gravity through an 18-guage, 1.5 in. long syringe needle.
[0031] A selected formulation was prepared by dissolving 3% (by weight) of P1 in a 20/80 (by weight) mixture of methoxypropyl cyanoacrylate and butyl cyanoacrylate containing 500 ppm of butylated hydroxyanisole and 3.3 ppm of pyrophosphoric acid stabilizers against free radical and anionic polymerization, respectively. More specifically, this entailed the following steps: (1) the P1 polymer was added to a flask and dried at 80° C. for 3 hours; (2) the cyanoacrylate monomers and the stabilizers were added; and (3) the resulting mixture was stirred at 80° C. until it became homogenous. The resulting formulation exhibited a comparative adhesive viscosity of 12.63 s and an adhesive joint strength of 28.35 N (using a fabric peel test).
Example 8
Preparation and Properties of Absorbable Cyanoacrylate Tissue Adhesive Formulation Using P-6 of Example 4 as a Rheology Modifier
[0032] The adhesive formulation was prepared by dissolving 5% (by weight) of P-6 in a 90/10 (by weight) mixture of methoxypropyl cyanoacrylate and ethyl cyanoacrylate containing 500 ppm of butylated hydroxyanisole and 3.3 ppm of pyrophosphoric acid as stabilizers against free radical and anionic polymerization, respectively. More specifically, this entailed the following steps: (1) the P3 polymer was added to a flask and dried at 80° C. for 3 hours; (2) the cyanoacrylate monomers and stabilizers were added; and (3) the resulting mixture was stirred at 80° C. until it became homogenous. The resulting formulation exhibited a comparative adhesive viscosity of 6.74 s and an adhesive joint strength of 34.96 N (using a fabric peel test).
Example 9
Preparation of a Doxycycline Hyclate Controlled Release Formulation Using P-2 from Example 3 and Determination of the Drug Release Profile
[0033] This entailed a three-step process, namely, mixing P-2 (from Example 3) with a diluent liquid excipient (from Example 5), acetylated polyethylene glycol-400 (PG-4A), preparation of an active formulation, and monitoring the drug release profile.
[0034] Mixing P-2 with PG-4A
[0035] For this, P-2 (3.2691 g) was placed in a glass vial and PG-4A (1.7603 g) was added. The contents of the vial were heated to 50° C. and mechanically mixed until a homogenous mixture developed. The final mixture was 65 weight percent P-2 with the remainder consisting of PG-4A.
[0036] Preparation of Active Formulation
[0037] To prepare a liquid vehicle, an aliquot of 2.0237 g of the P-2/PG-4A mixture was transferred to a glass vial, and doxycycline hyclate (434 mg) was added to the vial. Microparticles of acid-terminated polyglycolide (433 mg) were added to the contents of the vials. This was followed by heating to 50° C. and mixing mechanically to obtain a homogenous mixture. The resulting mixture was 70 weight percent liquid vehicle, 15 percent polyglycolide microparticles, and 15 percent doxycycline hyclate.
[0038] Release Study
[0039] The active formulation (1.0230 g) was placed in a small glass vial and heated to 50° C. to flow into bottom of vial and create a uniform coating and then was allowed to cool to room temperature. Phosphate buffer (10 mL, pH 7.2) was placed into the glass vial, which was transferred to a 37° C. incubator. The buffered solution (with released drug) was withdrawn at predetermined time points and replaced with 10 mL of fresh buffer. Aliquots of the release buffer were assayed by reverse phase HPLC, using a Waters Chromatography System with a C18 column, a gradient of 15-30% acetonitrile over 10 minutes, and detection at 350 nm; the amount of doxycycline released over time was determined. The HPCL data indicated a cumulative release at 23, 94, and 163 hours of 16%, 31%, and 45%, respectively.
[0040] Although the present invention has been described in connection with the preferred embodiments, it is to be understood that modifications and variations may be utilized without departing from the principles and scope of the invention, as those skilled in the art will readily understand. Accordingly, such modifications may be practiced within the scope of the following claims. Moreover, Applicant hereby discloses all subranges of all ranges disclosed herein. These subranges are also useful in carrying out the present invention.
|
Hydroswellable, absorbable and non-absorbable, aliphatic, segmented polyurethanes and polyurethane-urea capable of swelling in the biological environment with associated increase in volume of at least 3 percent have more than one type of segments, including those derived from polyethylene glycol and the molecular chains are structurally tailored to allow the use of corresponding formulations and medical devices as carriers for bioactive agents, rheological modifiers of cyanoacrylate-based tissue adhesives, as protective devices for repairing defective or diseased components of articulating joints and their cartilage, and scaffolds for cartilage tissue engineering.
| 2
|
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 09/714,424, filed Nov. 16, 2000, which is based on priority Provisional Application No. 60/165,857, filed Nov. 16, 1999, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to foam formulations and manufacturing methods and, in particular, to high performance microcellular foam, methods of manufacture and applications thereof.
[0004] 2. Description of the Prior Art
[0005] Solid cast polyurethane systems generally result from the reaction of an isocyanate, a short chain glycol (or amine), and a long chain polyol. To achieve optimal properties, the number of reactive isocyanate and hydroxyl (amine) groups for a given formulation should be nearly equal. The hardness or modulus of the resulting polyurethane product can be adjusted through the ratio of long chain to short chain polyols in the system.
[0006] The type of isocyanate, glycol, and polyol can be altered to achieve desired properties. The most popular isocyanates are based on methylene diisocyanate (MDI) or toluene diisocyanate (TDI). In the case of MDI-based systems, both monomeric and polymeric types can be utilized although the use of the monomeric 4,4′ isomer generally imparts the best properties. Long-chain polyols are most commonly polyester or polyether based. Polyether polyols are typically of the polytetramethylene glycol (PTMEG) or polypropylene glycol (PPG) variety. The PPG type systems are prepared through ring-opening polymerization of propylene oxide and are often copolymerized with ethylene oxide to impart specific properties to the material. The PPG ether systems, in general, offer a lower cost, lower performing alternative to PTMEG-ether systems. Common polyester polyols used in solid cast polyurethane chemistry involve adipate or caprolactone types. Polyester-based urethanes possess outstanding toughness and durability and offer advantages over polyether-based systems in cut and tear resistance. Due to this combination of properties, polyester-based systems are often best suited for demanding industrial applications.
[0007] Polyurethane systems can be classified according to when and how the components are brought together. So-called “one-shot” systems are formed by mixing the individual components all at once. “Quasi-prepolymer” systems are those in which a portion of the long chain polyol component is pre-reacted with the isocyanate to form an isocyanate-terminated prepolymer. To form the final product, this “quasi-prepolymer” (typically with an isocyanate content in the 15-25% range) is then reacted with the short chain glycol and the remainder of the long chain polyol component. “Full prepolymer” systems are prepared by pre-reacting the entire long chain polyol component with the isocyanate. The resulting prepolymer (with an isocyanate content typically less than 12% NCO) is then reacted (or cured) with the short chain polyol or amine to complete the reaction. Due to the high degree of reaction control, full prepolymer-based systems generally exhibit the best overall physical and dynamic properties of any polyurethane elastomer.
[0008] Microcellular polyurethane foams find usage in various applications including shoe soles, acoustical and isolation damping, engine and tool mounts, and seals and suspension systems. Many of these systems utilize one-shot or “quasi-prepolymer” systems using MDI-based technology where the MDI component has an isocyanate content in the 15-34% range. Such systems often contain PPG-type polyol components and, consequently, do not possess the extreme toughness and wearability required for high performance applications.
[0009] Microcellular polyurethane foams suitable for use in demanding industrial applications are not very common. The most common use is in parts known as “jounce bumpers” which act as damping components in automotive strut suspension systems. The chemical system is based on a polyester-based urethane prepolymer such as the one described in the present invention. However, the isocyanate component most often utilized in the jounce bumpers is 1,5-naphthalene diisocyanate (NDI), as contrasted with the MDI-based systems described herein. Improvement in foam properties of the current invention over typical microcellular products is achieved through the use of a prepolymer approach versus a quasi-prepolymer approach and the use of polyester-based long chain polyol components. This combination yields a microcellular material which displays outstanding physical and mechanical performance which, unlikely other commercial microcellular products, is suitable for highly demanding applications.
[0010] The use of these high performance microcellular systems eliminates current deficiencies of solid polyurethane systems for achieving certain property characteristics. One such problem has to do with the difficulty of achieving low durometer, low modulus solid polyurethane cast elastomers with properties capable of competing with soft (<˜70 Shore A) rubbers. Traditionally, the solution for this problem consists of adding plasticizers to polyurethane formulations to soften solid elastomers to the desired hardness. The problem with this solution is that while proper plasticization does reduce hardness and modulus effectively, other physical, mechanical, and dynamic properties are negatively affected, particularly cut/tear resistance and overall toughness.
[0011] Another typical problem encountered with prior art solid polyurethanes is the inability to achieve the compressive load profiles required for certain roller/wheel conveying systems, such as bowling ball lift wheels/tracks and corrugated zero crush rolls. To achieve proper compressive loads with solid elastomer materials, complex design elements must often be utilized. The problem with this solution is that the design elements lead to stress concentrations and fatigue points in material, thereby reducing product life. Further, from the processing standpoint, sophisticated designs lead to high tooling and engineering costs, which can lead to inefficient production.
[0012] The high performance microcellular products described in the present invention allow a method for achieving reduced hardness and lower modulus materials while maintaining excellent overall toughness and wearability. In addition, the present invention allows the method of achieving desired load compression profile using a compressible microcellular material, thereby allowing a solid cross-section design to improve part performance and reliability. These material and processing modifications result in design simplification, improved part performance and reliability, and improved processing efficiency. Examples will be presented for specific applications, which demonstrate advances in the art.
SUMMARY OF THE INVENTION
[0013] High performance microcellular polyurethane foam has been developed which is suitable for demanding applications requiring high toughness and excellent dynamic characteristics. The current invention includes full prepolymer systems with isocyanate contents in the 3-12% range. In addition, the high compressibility/extensibility of the cellular material provides a route for producing a low modulus material with physical properties typically not attainable in solid cast polyurethane systems. Such characteristics make the material suitable for numerous applications normally considered outside the realm of conventional solid systems. The unique property profile also allows part design modifications.
[0014] In addition, the techniques used to process the chemical system are different from standard solid cast polyurethane practice. Using particularly controlled water addition, foam surfactant addition, a modified catalyst system, adding a delayed action tin catalyst, and a reduced NCO/OH ratio, the process described herein creates a new high performance microcellular foam. This foam has special application for industrial parts that require a flexible, tough, highly compressible polyurethane material. For example, the present invention is particularly successful in the bowling equipment and the cardboard manufacturing industries.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 is a side view of a ball lift wheel using the current invention;
[0016] [0016]FIG. 2 is a cross-sectional view of a ball lift wheel using the current invention;
[0017] [0017]FIG. 3 is a cross-sectional view of the first embodiment of a zero crush roller using the current invention;
[0018] [0018]FIG. 4 is a side view of the first embodiment of a zero crush roller using the current invention;
[0019] [0019]FIG. 5 is a cross-sectional view of the second embodiment of a zero crush roller using the current invention;
[0020] [0020]FIG. 6 is a side view of the second embodiment of a zero crush roller using the current invention;
[0021] [0021]FIG. 7 is a cross-sectional view of the third embodiment of a zero crush roller using the current invention;
[0022] [0022]FIG. 8 is a side view of the third embodiment of a zero crush roller using the current invention;
[0023] [0023]FIG. 9 is a cross-sectional view of the fourth embodiment of a zero crush roller using the current invention;
[0024] [0024]FIG. 10 is a side view of the fourth embodiment of a zero crush roller using the current invention;
[0025] [0025]FIG. 11 is a cross-sectional view of the prior art bowling ball lift wheel;
[0026] [0026]FIG. 12 is a side view of the prior art bowling ball lift wheel;
[0027] [0027]FIG. 13 is a side view of the prior art zero crush roll;
[0028] [0028]FIG. 14 is a top view of the prior art zero crush roll;
[0029] [0029]FIG. 15 is a side view of a further prior art zero crush roll; and
[0030] [0030]FIG. 16 is a top view of a further prior art zero crush roll.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] The current invention involves modifications to existing full prepolymer systems and their processing to allow preparation of a high performance microcellular foam product. Similar to standard solid systems, one component of the system is an isocyanate terminated prepolymer with an isocyanate content less than 12%. The curative component consists of one or more short chain glycols. All work to date has involved MDI-ester prepolymers, although it is anticipated that the concept can be reasonably extended to other common prepolymer compositions, including TDI-based systems.
[0032] The method of producing the present invention includes, as a first step, the carefully controlled addition of water to the polyol component. The water reacts with the isocyanate end groups of the prepolymer to produce a carbamic acid intermediate. This intermediate immediately reacts with another isocyanate group to form a urea linkage and carbon dioxide gas. The liberated gas serves as the blowing agent in the system. As water level affects foam stiffness and density, water concentrations between 1%-5% of the curative component have been utilized. Water concentrations between 1.5%-3% of the curative component is the preferred range. By contrast, in standard solid systems, care is taken to eliminate all sources of moisture due to bubble formation and the effect of resultant voids on part aesthetics and performance.
[0033] Another step requires the addition of a foam surfactant to the polyol component. The surfactant stabilizes the bubbles formed in the blowing reaction to produce a finer and more consistent cell size and structure. Surfactant levels as low as 1% of the curative component have been found to be effective.
[0034] Also, the method of the present invention utilizes a modified catalyst system. A catalyst system is required which provides proper balance between the gelling and blowing reaction during mixing. The system consists of a standard solid cast polyurethane catalyst (i.e., DABCO 33LV) which, in the microcellular system, is effective in promoting the water reaction. In addition, a delayed action tin catalyst (i.e., Topcat 290) is added to drive the gelling reaction to completion. A ratio of 1.25:1 tin catalyst:solid cast polyurethane catalyst has been found to produce acceptable product. Without the tin catalysis, the integrity of the supporting polyurethane structure is slow to develop. As a result, fine cell structure is not achieved and dimensional stability of the foam is sacrificed.
[0035] The concentration of the catalyst in the polyol component can be adjusted to obtain the desired cream, tack-free, and demold times. Variables such as part size, part geometry, machine output, and productivity requirements will influence the catalyst level used. Concentrations of 0.5%-0.6% of the curative component has been used successfully to provide cream times of 10-20 seconds, tack free times of 45-60 seconds, and demold times of 10-20 minutes. These demold times represent a significant decrease over comparable solid cast systems which typically require 30 minutes to one hour to develop the material strength required to demold parts without damage.
[0036] Finally, this method requires stoichiometry adjustment. The ratio of isocyanate groups to hydroxyl groups (typically called NCO/OH index) is an important parameter in polyurethane processing. While solid cast systems can be processed throughout a wide range of NCO/OH indices, the best overall elastomer properties are typically obtained at ratios in the 1.02-1.05 range. The slight excess of isocyanate groups at these ratios leads to a slightly cross-linked structure which imparts the properties characteristic of full prepolymer solid cast systems, i.e., low compression set, excellent dynamic properties, and temperature resistance.
[0037] It has been found that the microcellular systems described in the current invention cannot be successfully produced within the typical NCO/OH ratios greater than 1.02, which are characterized by slow build-up of foam integrity, resulting in a product with coarse cell structure and poor dimensional stability. Similar results have been seen at NCO/OH ratios below 1.00. Based on observations thus far, acceptable cell structure can be obtained at ratios between 0.96 and 1.02. However, for production of optimum microcellular product, NCO/OH index should be controlled between 0.98 and 1.00, with excess of one component over the other not exceeding a maximum percentage of 2%.
[0038] Processing methods for the microcellular systems are similar to solid cast prepolymer systems in many respects. The components are heated and accurately metered via precision gear pumps into a dynamic mixhead. A prepolymer temperature of 170° F. to 190° F. is generally required to reduce viscosity to the 500-1500 centipoise level, allowing more efficient pumping and mixing with the low viscosity curative. Curative temperatures between room temperature and 150° F. are typical for standard liquid curatives. Solid curatives require temperatures above their melting point. Once mixed, the material is dispensed into properly designed capped molds with appropriate venting to allow displacement of air as the system foams within the cavity. The following steps represent further unique differences in manufacturing the present invention versus its solid system counterparts.
[0039] The removal of dissolved gas from the prepolymer component of a solid cast system is critical for producing high quality void-free parts and is standard practice in solid cast polyurethane processing. Degassing is typically accomplished by either batch or continuous (thin film) methods by subjecting the prepolymer resin to a vacuum of at least 25 mm Hg until the majority of the dissolved gases are removed. It has been found that the use of the standard prepolymer degassing step in the preparation of the microcellular foam of the present invention produces an unacceptable product with coarse, non-uniform cell structure. Thus, unlike solid cast systems, dissolved gases in the system of the present invention need not be removed and, in fact, are critical to the formation of acceptable foam structure. The dissolved gas acts to provide nucleation sites, which stabilize initial bubble formation.
[0040] The formation of small, well-dispersed bubbles during the initial stages of reaction are critical for producing the fine uniform cell structure noted in these systems. While eliminating the standard prepolymer degassing step is the most convenient approach to ensure gas content in the system, introduction of a gas at the mixhead is also a feasible approach. This can be accomplished effectively through the use of a mixer impeller design, which acts to whip air into the mixture. Another approach is the addition of a controlled amount of gas into the mixhead. This can be accomplished, for example, with a flowmeter-pressure regulator-needle valve arrangement capable of maintaining and controlling low gas flow rates. Still another method is to solubilize an otherwise less soluble gas (i.e., N 2 ) into one or more of the system components by maintaining the component(s) under pressure until entry into the mixhead. The resulting pressure drop as the component(s) enters the relatively low pressure mix chamber environment results in the gas escaping from solution and providing needed nucleation sites for bubble formation.
[0041] Because of the nature of the catalyst system used, processing temperatures are also critical to producing the present invention. As mentioned above, component temperatures for microcellular systems lie in the same range as standard solid cast systems. However, the typical mold temperature range utilized for solid cast systems (200-250° F.) is not appropriate. Due primarily to the temperature dependence of the tin catalyst present in the system, mold temperature must be maintained between 160-200° F. At temperatures outside of this range, unacceptable foam product is produced due to an improper balance in the competing water and urethane reactions. Defects due to improper temperature control include poor cell structure, scorched part surface, and other surface defects.
[0042] The microstructure of cellular polyurethane consists of thin polyurethane/urea walls which define domains (called cells) containing air or other gas. Thus, by definition, the density of microcellular compounds is somewhat less than that of the solid elastomer. The property profile of a given microcellular system is largely determined by this density, which must be taken into consideration during the design and production of foam parts. Various molded densities may be obtained from a given microcellular formulation by filling the mold cavity to different degrees. Consequently, tight control over the shot size of each pour is necessary to produce parts with a consistent molded density.
[0043] The so-called free rise density is defined as the density of the foam when allowed to blow and rise without constraint. The free rise density is characteristic of a given formulation and can provide a check that the formulation and parameters are within proper ranges. Factors affecting free rise density are water content in the formulation, catalyst level, and mold and component temperatures. Typically, enough material is introduced into the cavity to produce a molded part density, which is 1.5 to 2 times the free rise density. With insufficient material addition, the microcellular material may not completely fill the cavity or it may collapse or shrink after demold. If too much material is added, the pressure build-up in the mold may become excessive and the part may expand after demold making it difficult to hold dimensional tolerances. For the microcellular compounds of the current invention, free rise densities of 16-20 pounds per cubic foot (pcf) and molded part densities in the 25-40 pcf range are typical.
[0044] Additional high temperature cure of solid cast elastomer parts after demold is standard practice. This postcure is necessary to complete the curing process and provide a material with optimum properties. Typical postcures of 16 hours or more at temperatures in excess of 230° F. are common. Microcellular parts develop strength very quickly during the reaction. In a very short time period after mixing, near optimum physical properties are achieved. As a result, microcellular parts can be demolded much faster than solid cast parts and any additional postcure cycle can be eliminated.
[0045] The microcellular materials described above offer many advantages over solid systems. The microcellular materials provide the ability to achieve low modulus, highly flexible polyurethane material and parts which exhibit excellent physical properties, including high toughness, tear resistance, high compressibility, and puncture resistance. These methods produce excellent dynamic properties, including greater fatigue resistance due to less resistance to deformation. Easier and more efficient processing occurs due to faster demold times, no need for a prepolymer degassing step or postcure cycle, and reduced care needed in material handling to protect components from atmospheric moisture.
EXAMPLE
[0046] Isocyanate Prepolymer: Baytec MS-242 (6.7% NCO MDI-ester prepolymer) Curative.
64% Triethylene Glycol 32% 1,4-Butanediol 2.50% Water 0.30% Topcat 290 catalyst 0.24% DABCO 33LV catalyst 1.00% DC-193 Surfactant
[0047] The components, when mixed at an NCO/OH ratio of 1.00, produce a microcellular product with a free rise density of 17-18 pounds per cubic foot (pcf), a cream time of 12-15 seconds, a tack free time of 45-60 seconds, and a demold time of 15 minutes. Parts molded in the 25-30 pcf range have been found to be useful in a number of applications including those described below.
[0048] Further, the polyester-based microcellular foam product of the present invention possesses superior properties when compared to prior art polyether-based microcellular systems, as shown in the following table.
Polyether System (from commercial Polyester System product information (of Present Invention) by Bayer Corp.) Tensile Strength 400-520 psi 150-300 psi (ASTM D412) Elongation 470-520% 250-350% (ASTM D412) Tear Strength 70-73 lbf/in 25-40 lbf/in (ASTM D624)
[0049] A first application utilizing the present invention includes bowling ball lift wheels and lift tracks, which are used as components of OEM bowling equipment and which are designed to change the elevation of bowling balls from below grade to a comfortable height at the ball return station. As seen in FIGS. 1 and 2, the bowling ball lift wheel 10 consists of a circular hub 12 surrounded by a circular molded foam 14 manufactured from the present invention. Overall, the bowling ball lift wheel 10 appears tire-like, with the circular hub 12 acting as the rim and the circular molded foam 14 acting as the tire. There are two bowling ball lift wheels 10 used in a counter rotating sense on each ball lift mechanism. The bowling ball lift wheels 10 are separated a certain distance in a vertical sense and each bowling ball lift wheel 10 is nested inside a set of two concentric arcs of opposite orientation. The lift tracks (not shown) are mounted to two parallel steel “C” tracks which comprise each concentric arc. The lift tracks provide the proper fit to effectively convey the ball through the mechanism as well as to provide a soft, durable transport surface which will not mark or mar the ball.
[0050] Once ejected from the back of the alley, the bowling ball returns via a track to the ball lift mechanism. At this point, the ball is trapped by way of interference between the lower bowling ball lift wheel 10 and the lift tracks. The lower bowling ball lift wheel 10 , (rotating in a counter-clockwise direction as viewed from the left), deforms against the ball surface, generating force in order to lift the bowling ball through the arc until it is contacted by the upper bowling ball lift wheel 10 . At this point, the ball is transferred to the upper lift tracks and upper bowling ball lift wheel 10 , (rotating clockwise as viewed from the left), the direction of the ball is changed and the ball rolls along the upper arcs until interference is lost and the ball is released at the new elevation.
[0051] The advantages of using the present invention in this application are numerous. The soft pliable surface of the present invention is much softer than any current lift wheel designs. This results in a component that will not damage the surface of bowling balls and is completely non-marking. The solid cross-section of the bowling ball lift wheel 10 of the present invention is much less susceptible to failure when compared to the webbed design of the prior art waffle-style wheel (shown in FIGS. 11 and 12) and thinner cross-section of the V-style wheels. Further, the solid cross-section transfers much less force to the interface of the bonded metal and foam, reducing failures associated with delamination of the circular molded foam 14 and the circular hub 12 . The simple design allows for solid cross-section parts using less material than current designs, and the pliable full cross-section design allows for continual wear without failure. The damping nature of the present invention allows for smoother, quieter operation. The present invention is manufactured from simple inexpensive tooling compared to current designs, and additionally, is manufactured much more efficiently than cast elastomer designs.
[0052] A second application of the present invention involves zero crush rolls 16 , which are used in the manufacturing process for producing corrugated board-stock. During the manufacturing process, rolls of paper stock are fed into a corrugator machine. The corrugator applies a liquid starch and glue to the surfaces of the paper stock. Once the starch and glue are applied, the paper is fed through a series of rollers that form the paper to a corrugated configuration. After the paper stock is corrugated, additional sheets of paper are laminated to both sides. The end result is a corrugated board made up of various layers of paper stock. The process of manufacturing the corrugated board-stock is a continuous process that requires a conveyor system to handle the fresh board so as not to crush the corrugated portion of the board.
[0053] The conveyor system is made up of a series of parallel steel shaft rollers mounted with bearings to a steel frame. As seen in FIGS. 3 and 4, the zero crush rolls 16 of the first embodiment consist of a circular molded solid cast elastomer 18 and a circular molded foam 14 of the present invention bound to the circular molded solid cast elastomer 18 . The zero crush rolls 16 are either pressed onto or mounted to the steel rollers with the circular molded solid cast elastomer 18 capturing a bearing. The zero crush rolls 16 are designed to deflect easily under the weight of the board-stock being conveyed. The deflection of the zero crush rolls 16 preserves the integrity of the corrugated configuration as it is being conveyed in the wet state.
[0054] Prior art zero crush rolls, as seen in FIGS. 13-16 are designed with two concentric rings that are joined together by a series of angular positioned ribs or ovular cut-outs. The preferred material is polyurethane that allows the roller to be cast as a homogeneous part. The thickness of these angular ribs or ovular cut-outs, along with the spacing, determines the deflection modulus of the prior art zero crush rolls. As the board-stock is conveyed, the ribs or cut-outs on the zero crush rolls are constantly flexing. This constant flexing causes the ribs and cut-outs to fatigue resulting in the failure of the zero crush rolls.
[0055] The zero crush rolls 16 of the present invention do not require ribs by design, eliminating the major cause of failure in the current zero crush rolls. By engineering the ribs out of the wheels, the end user can expect longer life from them. This extra life reduces machine downtime due to fewer changeovers, therefore improving machine productivity. Due to the design simplification, the tooling cost to produce the zero crush rolls 16 is reduced significantly. This design simplification allows higher quality zero crush rolls 16 to be produced without incurring extra expense. This equates to a cost saving for the end user. The same tooling can be used to produce a variety of zero crush rolls 16 that have different deflection modulus properties. This is accomplished by changing the density of the present invention.
[0056] The second embodiment of the zero crush rolls 16 application is shown in FIGS. 5 and 6. This embodiment varies the shape of the circular molded solid cast elastomer 18 , but as to the present invention, utilizes the same circular molded foam 14 . Similarly, the third embodiment of the zero crush rolls 16 application, as seen in FIGS. 7 and 8, differs from the first and second embodiments only with respect to the share of the circular molded solid cast elastomer 18 . In the third embodiment, again the circular molded foam 14 of the present invention is bound to the circular molded solid cast elastomer 18 . Finally, FIGS. 9 and 10 show a fourth embodiment of the zero crush rolls application. Again, this embodiment uses the circular molded foam 14 of the present invention bound to a circular molded solid cast elastomer 18 of a differing cross-section than the previous embodiments.
[0057] The present invention is also applicable to other applications in addition to those mentioned above. In the bowling industry, the present invention can be utilized in the manufacture of ball lift wheels, ball lift tracks, pit cushions, deck pads and ball polishing tools. In the corrugated industry, the foam of the present invention may be used in manufacturing zero crush rolls, lead edge feed wheels, pull rolls, taper rolls, and die ejection material. The present invention is also applicable in the creation of sporting goods, such as archery targets, bicycle seat cushions, protective pads and helmets. Various other applications are also anticipated, for example, medical body support pads, outrigger pads, impact absorbing sheets, custom packaging, anti-vibration spacers and mounts, springs, protective coverings, sound dampening material, seals, and insulation.
[0058] Although the specific description of the herein disclosed invention has been described in detail above, it may be appreciated that those skilled in the art may make other modifications and changes in the invention disclosed above without departing from the spirit and scope thereof.
|
The present invention is a high performance microcellular polyurethane foam suitable for numerous applications normally considered outside the realm of conventional solid systems. Also included in the present invention is a method of manufacturing the high performance microcellular polyurethane foam using controlled water addition, foam surfactant addition, a modified catalyst system, the addition of a delayed action tin catalyst and a reduced NCO/OH ratio. The present invention has special application for industrial parts, especially the bowling equipment industry and the cardboard manufacturing industry.
| 2
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to forming spline teeth or gear teeth, and more particularly to cold extruding helical teeth in a gear blank workpiece.
[0003] 2. Description of the Prior Art
[0004] Planetary gear units of the type used in automotive transmissions include ring gears having internal helical teeth rather than straight gears even though helical gear teeth are more difficult to form. The internal gear teeth must be formed with very precise dimensions and spacing in order to perform correctly.
[0005] The helical teeth may be formed by broaching, which is a cutting process in which a large broaching bar with cutting teeth is pulled through a gear blank to form the teeth. Broaching is a costly process, which requires a significant investment in dedicated machinery, lead bar, cutting tools and cutting oils. Broaching can only be applied to parts accessible in both axial directions since the long broach bar must be pulled through the inside of a gear blank to cut the teeth.
[0006] The helical teeth may be formed by gear shaping, another cutting process used to fabricate internal helical teeth. Although it is a slower process than broaching, it can be used to form blind end as well as through parts for high volume production. Even so, this process also requires an investment in expensive machinery and cutting tools.
[0007] Helical teeth may be formed by cold extrusion, in which the teeth are formed, rather than cut, into the part. A precision ground, hardened mandrel formed with external helical die teeth is forced into a workpiece, whose internal surface is formed with the negative contour of the die teeth. When helical teeth are being extruded, the mandrel must be guided in a helical path through the workpiece. This guidance combines axial translation and rotation about a central axis.
[0008] According to conventional practice, extrusion of helical ring gears requires a specific helical lead guide as part of each tool set to produce gear teeth at the proper helical angle. The lead guide is an expensive, large element of the die set and must be machined to precise dimensions. The lead mechanism requires a significant portion of the vertical dimension of the die set, and increases the total size of the hydraulic press. A lead guide and broach bar must be held in inventory for each product being made.
[0009] A need exists in the metal forming industry for an efficient, reliable technique for extruding internal and external helical gear teeth without using a lead guide to control the helical path of the mandrel through the material of the workpiece.
SUMMARY OF THE INVENTION
[0010] An apparatus for extruding helical teeth in a gear blank includes a press including a die plate and a die base, the die plate being movable along an axis relative to the die base, the die base supporting the gear blank. A mandrel, aligned with the axis and moveable with the die plate along the axis, includes a surface that includes helical die teeth. A motor of a programmed servo mechanism drives the mandrel in rotation about the axis as the mandrel moves axially relative to the gear blank, creating a helical path.
[0011] The servo motor and controller provides several advantages specific to the process of extruding helical gears including smaller size requires less die opening height; faster cycle time in extruding each gear, functional flexibility by programming the controller to control gear extrusion with many different helical gears and helix angles; fast die changing between different products, sensors for monitoring the extrusion process; and reduced the cost of the extrusion tooling and the hydraulic press.
[0012] The servo motor can be programmed to assist in the extrusion process by generating rotational torques while the hydraulic press actuates in the downward direction permitting better control of forces required to produce precision formed gear tooth profiles.
[0013] Moreover, the lead guide is replaced with a computer controlled electronic or hydraulic servo mechanism, which provides proper rotation of the mandrel to impart the exact helical gear geometry required for the gear being processed. The servo mechanism is much smaller than the fixed lead guide and is programmable for many different helical gear lead angles.
[0014] The servo controls are linked to a computer which controls axial movement and radial forces of the mandrel, thereby coordinating the press actuation sequence with the rotation and eliminating need for the mechanical lead guide.
[0015] The scope of applicability of the preferred embodiment will become apparent from the following detailed description, claims and drawings. It should be understood, that the description and specific examples, although indicating preferred embodiments of the invention, are given by way of illustration only. Various changes and modifications to the described embodiments and examples will become apparent to those skilled in the art.
DESCRIPTION OF THE DRAWINGS
[0016] The invention will be more readily understood by reference to the following description, taken with the accompanying drawings, in which:
[0017] FIG. 1 is a front view of an extrusion press equipped with a servo motor for forming internal helical gear teeth on a gear blank;
[0018] FIG. 2 is front view of a mandrel used in the extrusion press of FIG. 1 ; and
[0019] FIG. 3 is front view of a mandrel and die base used to form external helical gear teeth in a gear blank.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] Referring first to FIGS. 1 and 2 , an extrusion die assembly 12 , mounted in a hydraulic press 14 , includes a lower die plate 16 , resting on a base portion 18 of the press 14 , and an upper die plate 20 . Die guide posts 24 extend between upper die plate 20 and lower die plate 16 . One end of each die guide post 24 is fixed to upper die plate 20 ; the opposite end of each die guide post 24 has a ball bearing cage 26 attached to it. Affixed to lower die plate 16 are guide bushings 28 , with each guide bushing 28 aligned with one ball bearing cage 26 . Ball bearing cages 26 telescopically slide into their respective guide bushings 28 to allow axial movement of upper die plate 20 relative to lower die plate 16 , minimizing friction and maintaining the two die plates 16 , 20 mutually parallel. The assembly 12 is concentric with and translates along an axis 29 .
[0021] A support plate 30 , guided on the guide posts 24 , is secured to the upper die plate 20 for movement with plate 20 along axis 29 . A mandrel 32 is fastened to support plate 30 by a bolt 34 , which slips through a bore 36 in the center of mandrel 32 and engages a tapped screw thread in support plate 30 . Dowels 38 mate both with dowel holes 40 in support plate 30 and corresponding dowel holes 42 in mandrel 32 . Mandrel 32 is formed with external die teeth 46 , a lead surface 47 , and a single step 48 , which is preferred to a multiple-step mandrel. The helix angle of die teeth 46 is the same as that desired in the gear to be formed from the workpiece.
[0022] A load cell 50 , mounted on lower die plate 16 , includes force sensors mounted within it and electrically connected to a controller. Load cell 50 senses the magnitude of load and torque applied to it during the forming operation. To control the forming process, force sensors are used to control both the downward press motion and the rotational torque provided by the servo mechanism. If the load is out of predetermined ranges of these parameters, then the press 14 will stop the forming operation so that the press equipment can be checked. Load cell 50 is optional, and the extrusion process can be conducted without this piece of equipment, if so desired.
[0023] Mounted on load cell 52 is a die base 50 . A retainer ring 54 , mounted on die base 50 , has a cylindrical central cavity. A hardened sleeve insert 56 , fitted within the retainer ring 54 , surrounds the workpiece gear blank 58 . The die base 50 supports the gear blank 58 axially during the forming process. Retainer ring 54 , sleeve insert 56 and gear blank 58 are located concentric with axis 29 and mandrel 32 . The gear blank 58 is formed with a cylindrical central cavity 53 that is aligned with axis 29 .
[0024] A gear blank 58 includes an annular, cylindrical surface of controlled diameter, in which the internal helical gear teeth will be extruded during the forming process. FIG. 1 shows a ring gear blank 58 inserted into sleeve insert 56 .
[0025] A servo motor 90 is secured to upper die plate 20 , faces mandrel 32 , and has its shaft driveably connected to the mandrel, such that the armature of the servo motor and the mandrel rotate about axis 29 as a unit in response to control signal produced by a controller 92 .
[0026] Electronic signals 94 , produced by load cell 52 and representing the magnitude of the extrusion force and torque and the speed of press 14 are supplied to controller 92 as input. Electronic signals 96 produced by sensors 98 representing the angular displacement of mandrel 32 and the rotor of servo motor 90 from a reference position about axis 29 , and the speed of motor 90 are supplied to controller 92 as input. Electronic signals 100 produced by sensor 102 representing the angular displacement of workpiece 58 from a reference position about axis 29 are also supplied to controller 92 as input.
[0027] Controller 92 preferably includes an electronic microprocessor 104 , electronic memory 106 , and signal conditioning circuits, which communicate mutually and with an output 110 over a data bus 112 . The memory contains a control algorithm, which is executed using variables represented by the input signals and is programmed to produce many different helical gear lead angles and continually adjusts to deviation from expected behavior of the press 14 .
[0028] Control signals 114 are carried from the output 110 of controller 92 to a servo motor control (not shown), which actuates servo motor 90 to rotate about axis 29 in response to the control signals output by controller 29 . Similarly, controller 92 causes the assembly 12 to translate vertically along axis 29 .
[0029] The extrusion assembly 12 is used in a cold extrusion process for forming internal helical teeth in gear blanks 58 , with tight control of lead accuracy.
[0030] In operation, a gear blank 58 is inserted into ring insert 56 . Hydraulic press 14 is activated and forces the upper die plate 20 downward toward lower die plate 16 , guided by die guide posts 24 .
[0031] This axial translation carries mandrel 32 toward gear blank 58 such that the lead surface 47 enters the central opening 53 in the workpiece 58 . Servo motor 90 causes mandrel 32 to rotate about axis 29 to a desired angular position, at which the helical die teeth 46 on the external surface of mandrel 32 first contact the gear blank workpiece 58 . When the mandrel 32 is in its desired angular position, hydraulic press 14 is actuated to continue its axial path and servo motor 90 is actuated to rotate at a speed that is related to the speed of its axial path such that the internal gear teeth are formed on the workpiece 58 with the desired helix angle.
[0032] Die teeth 46 on mandrel 32 engage the inner surface of gear blank 58 and move downward into the material of the workpiece with a helical motion as they are forced into the gear blank, thereby forming helical gear teeth. When the predetermined depth of finished gear teeth is reached, hydraulic press 14 stops pressing on upper die plate 20 and retracts the upper die plate 20 and mandrel 32 . Servo radial forces are used to form the gear tooth flanks during the upper stroke of the press and die.
[0033] This movement causes mandrel 32 to withdrawal upward and to lift the workpiece 58 from the surface of the die base 50 . A box stripper 120 , secured to the die base 50 , contacts the upper surface 122 of the workpiece 58 forcing it from the mandrel 32 and allowing the mandrel to withdraw from the extruded gear. The motion of withdrawal will follow that of insertion.
[0034] The finished ring gear is then removed from press 14 and another gear blank 58 is inserted in its place preparatory to repeating the forming process. Because the travel distance of the press 14 is short, the length of the cycle period is short time and throughput is increased substantially over conventional techniques.
[0035] Although the extrusion method has been described with reference to external helical mandrel teeth 46 on the workpiece 58 being used to extrude internal teeth on the blank 58 , if external helical gear teeth are to be extruded on a workpiece 158 , as FIG. 3 illustrates, a mandrel 132 is formed with a central cylindrical cavity 153 , which surrounds the outer surface of the workpiece 158 and is aligned with axis 29 . The inner surface of workpiece 158 is supported by a cylindrical plug 160 located in the cylindrical cavity 53 of the workpiece. The inner surface of mandrel 132 is formed with helical die teeth 146 . The servo motor 90 is driveably connected to mandrel 132 and rotates the mandrel as the press 14 forces the die teeth 146 axially into and through the wall of the workpiece 158 , thus forming external helical gear teeth on the outer surface of the workpiece or gear blank 158 .
[0036] In accordance with the provisions of the patent statutes, the preferred embodiment has been described. However, it should be noted that the alternate embodiments can be practiced otherwise than as specifically illustrated and described.
|
An apparatus for extruding helical teeth in a gear blank includes a press including a die plate and a die base, the die plate being movable along an axis relative to the die base, the die base supporting the gear blank. A mandrel, aligned with the axis and moveable with the die plate along the axis, includes a surface that includes helical die teeth. A servo motor drives the mandrel in rotation about the axis to the required helix angle as the mandrel moves axially relative to the gear blank.
| 5
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an anesthetic delivery system and in particular to a system adapted to re-use anesthetic that remains unabsorbed by a patient from a previously inhaled anesthetic dose.
[0003] 2. Description of the Prior Art
[0004] It is know from U.S. Pat. No. 4,015,599 to provide an anesthetic delivery system having a delivery unit that houses a carbon dioxide absorber and a reversible action anesthetic adsorption filter arranged in series and in gaseous communication with a gas flow passage that provides a flow path for gas through the unit via the carbon dioxide absorber and the anesthetic adsorption filter. A charge of a gas-forming anesthetic is also provided as part of the system, pre-loaded into the anesthetic adsorption filter.
[0005] In use, the unit of the known anesthetic delivery system is disposed in gas flow connection with a tubing circuit of a so-called “closed” inhalation anesthesia system. The unit is intended to be used in a manner such that exhaled breathing gas within the tubing circuit passes first through the carbon dioxide absorber and then through the adsorption filter to collect. This anesthetic gas is then supplied into the tubing circuit for inhalation by the patient, together with fresh breathing gas that is added after the unit to compensate for the gas that was consumed.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to provide an anesthetic delivery system adapted for use in a so-called “open” inhalation anesthesia system and which also allows the re-use of exhaled anesthetic.
[0007] This object is achieved in accordance with the present invention by an anesthetic delivery system having a delivery unit with two internal gas flow passages, an exhalation gas flow passage that conducts gas through the adsorption filter only, and an inhalation gas flow passage that conducts gas through first the adsorption filter and then through the carbon dioxide absorber. Thus any unused anesthetic in exhalation gas is retained by the filter and is returned (“reflected”), essentially free of carbon dioxide, for re-inhalation by a patient while permitting the majority of exhaled carbon dioxide to pass through the unit. In this manner the lifetime of the anesthetic charge may be extended without increasing its size and the amount of carbon dioxide absorber material may be reduced compared to the known system, thereby enabling a reduction in material costs and size of the delivery unit.
[0008] Usefully a bypass gas flow passage may be included within the unit and configured to provide a flow path for an amount, preferably a variable amount, of gas from the inhalation passage to bypass the anesthetic filter. In this manner take up of anesthetic may be controlled by controlling the gas flow through the anesthetic adsorption filter.
[0009] A variable flow restriction may be provided within either of the bypass gas flow passage and the inhalation gas flow passage to regulate the flow of gas in the inhalation line through the filter and thereby variably control the concentration of anesthetic in the gas that passes out of the delivery unit. Usefully the variable flow restriction may be adapted to automatically regulate the flow of gas dependent on a sensed concentration of anesthetic in the gas. Preferably a material, such as silicone rubber, that reacts to change its physical dimensions in response to an exposure to anesthetic, is employed in the variable flow restriction. In this way sensing of the anesthetic concentration and the dependent control of the flow restriction may be carried out within the delivery unit without the need of additional electronic sensor or control arrangements.
[0010] The above object also in achieved in accordance with the present invention by an inhalation anesthetic system having a mechanical breathing aid which may be a ventilator or respirator of a stationary system or which may be, for example, a compressible bag or bottled gas supply, connectable to the airways of a patient by a gas flow circuit having a common gas flow section in which inhalation gas from the breathing aid can flow towards the patient and in which exhalation gas from the patient can flow towards the breathing aid. A delivery unit of the anesthetic delivery system is provided in fluid communication with the flow circuit, preferably the common gas flow section, so that inhalation gas can flow through the unit to receive a dose of the anesthetic agent held by the absorption filter and so that the exhalation gas can flow through the unit to deposit unused anesthetic agent in the absorption filter together with a small amount of the carbon dioxide present in the exhalation gas.
DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows schematically a first embodiment of an anesthetic delivery system according to the present invention;
[0012] FIG. 2 is a schematic representation of an inhalation anesthetic system according to the present invention.
[0013] FIG. 3 shows schematically a second embodiment of an anesthetic delivery system according to the present invention.
[0014] FIG. 4 shows part of a third embodiment of an anesthetic delivery system according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] Considering now the anesthetic delivery system of FIG. 1 , a delivery unit 2 is, in the present embodiment, formed with ports 6 a , 6 b for providing gas communication between internal and external the unit 2 . Gas flow directions through the unit 2 , when in use are shown, in FIG. 1 by the arrows.
[0016] The port 6 a provides for gas communication between external the unit 2 and a common flow passage 8 a internal the unit 2 whilst the port 6 b provides for gas communication between external the unit 2 and a common flow passage 8 b internal the unit 2 . These common flow passages 8 a , 8 b form part of both an inhalation gas flow passage (for gas flowing within the unit 2 from port 6 a , towards the port 6 b ) and an exhalation gas flow passage (for gas flowing within the unit 2 from port 6 b , towards the port 6 a ).
[0017] A reversible action anesthetic (adsorption/desorption) filter 10 formed of a suitable sorption material for anesthetic agent, such as zeolites of crystalline aluminum silicates which may be pellets or supported on a carrier; an activated carbon filter such as formed from carbon-impregnated material, carbon fiber cloth, or granulated or microporous carbon material; or other microporous material, is arranged in direct gas communication with the common flow passage 8 a . In the present embodiment this anesthetic sorption filter 10 is formed into two regions. A first region 10 a is provided initially free of the anesthetic agent and a second region 10 b is pre-loaded with an anesthetic agent to be delivered to a patient. Optionally and as illustrated in the present embodiment, a first removable sealing membrane 4 a , such as may be formed from an impermeable plastics material, is located between the first region 10 a and the second region 10 b to act as a barrier for the transport of the pre-loaded anesthetic agent into the second region 10 b . A second removable sealing membrane 4 b is located to seal the second region 10 b against escape of anesthetic agent from the filter 10 . The two membranes 4 a , 4 b are removable from the filter 10 by pulling on externally accessible tab sections and are intended to be removed immediately before use of the unit 2 . In this manner the pre-loaded delivery unit 2 may be stored for extended periods without loss of anesthetic from the second region 10 b of the filter 10 .
[0018] The filter 10 is located within the delivery unit 2 with the anesthetic free region 10 a relatively closer to the port 6 a and in fluid communication with the common flow passage 8 a . Pre-loading may be achieved in a number of ways, for example by passing an anesthetic containing gas, in this embodiment preferably in a direction from the port 6 b to the port 6 a , through the unit 2 before any removable sealing membrane 4 a , 4 b is in place and until a required amount of anesthetic agent has been retained by the anesthetic filter 10 . This can be monitored by monitoring the anesthetic concentration in gas exiting the unit 2 through the port 6 a . Pre-loading of the filter 10 may alternatively be carried out by passing an anesthetic containing gas through it before it is placed within the delivery unit 2 .
[0019] A flow channel 12 is provided within the unit 2 for fluid communication between the second region 10 b of the anesthetic filter 10 and a carbon dioxide absorber 14 . A one-way valve 16 is disposed relative to the carbon dioxide absorber 14 to prevent gas flow into the absorber 14 from the port 6 b.
[0020] A bypass gas flow passage 18 is connected through an opening 20 with the common flow passage 8 a at a location between the port 6 a of the unit 2 and the anesthetic filter 10 .
[0021] A one-way valve 22 is provided to permit gas flow along the bypass gas flow passage 18 in a direction from the common flow passage 8 a only. The bypass gas flow passage 18 is arranged to provide a flow path for gas from the port 6 a to the port 6 b , avoiding the anesthetic sorption filter 10 and in the present embodiment terminates at an opening 24 in the flow channel 12 . A variable flow restriction 26 is provided in communication with the bypass gas flow passage 18 and is movable to vary the resistance to gas flow within the bypass gas flow passage 18 .
[0022] A flow passage 28 within the delivery unit 2 communicates with the common gas flow passage 8 b ; with the second region 10 b of the anesthetic sorption filter 10 through the opening 24 in the flow channel 12 and forms part of an exhalation gas flow passage. The flow passage 28 is here shown to be provided with a one-way valve 30 to ensure gas flow through the passage 28 in one direction only—from the port 6 b towards the anesthetic filter 10 , avoiding the carbon dioxide absorber 14 .
[0023] An exemplary “open” inhalation anesthetic system 32 is shown in FIG. 2 . A mechanical breathing aid 34 , such as a ventilator, is shown in use in gas communication with the airways of a patient 36 . The system 32 is provided with a common gas line 38 for the delivery to and recovery from the airways of a patient 36 of anesthetic containing gases. Separate inhalation 40 and exhalation 42 gas lines are provided to connect the breathing aid 34 with the common gas line 38 .
[0024] The anesthetic delivery unit 2 of FIG. 1 is shown here as being series connected to the common gas line 38 so that gas passing both to and from the patient will pass through the unit 2 . The unit 2 is oriented within the common gas line 38 so that inhalation gas from the breathing aid 34 will enter the unit 2 through the port 6 a and exhalation gas from the airways of the patient 36 will enter the unit 2 through the port 6 b . To facilitate this orientation a visible indication, such as an arrow 44 showing the intended direction of gas flow through the unit 2 towards the patient 36 , may be provided on an external surface of the unit 2 .
[0025] In use the delivery unit 2 is intended to receive inhalation gas for inhalation by a patient 36 through the port 6 a and into the common gas flow passage 8 a . This inhalation gas may then be divided to flow partly through the anesthetic filter 10 and partly through the bypass gas flow passage 18 to avoid the filter 10 . The gas flowing through the filter 10 picks up anesthetic agent together with carbon dioxide that may be present within the filter 10 and flows towards the carbon dioxide absorber 14 . It will be appreciated that by moving the flow restriction 26 to alter the resistance to flow it presents then the amount of inhalation gas flowing through the absorption filter 10 can be varied and the concentration of anesthetic in the inhalation gas that exits the unit 2 through the port 6 b controlled.
[0026] In the present example this anesthetic containing inhalation gas is recombined with the inhalation gas from the bypass gas flow passage 18 in the flow channel 12 before it passes through the carbon dioxide absorber 14 . Carbon dioxide that was picked up by the inhalation gas as it passed through the anesthetic filter 10 will be captured by the carbon dioxide absorber 14 . The essentially carbon dioxide free inhalation gas then flows through the one-way valve 16 , along the common flow passage 8 b and out of the delivery unit 2 through the port 6 b carrying with it a dose of anesthetic for inhalation by the patient 36 .
[0027] Exhalation gas from the patient 36 will typically contain carbon dioxide and an amount of unused anesthetic. In use the delivery unit 2 is intended to receive this exhalation gas through the port 6 b and in to the common flow passage 8 b . The combination of one-way valves 16 , 22 , 30 ensures that exhalation gas flows only through the exhalation flow passage 28 , via the gas flow channel 12 , and into the anesthetic filter 10 , avoiding the carbon dioxide absorber 14 . As the exhalation gas passes through the filter 10 any unused anesthetic in the gas will be retained together with a small amount of the carbon dioxide that will also be present in the exhalation gas. The substantially anesthetic free exhalation gas then flows into the common flow passage 8 a and out of the unit 2 through the port 6 a . In this manner the effectiveness of the delivery unit 2 in delivering anesthetic doses is prolonged since the anesthetic charge that was initially loaded into the sorption filter 10 is partially restored with unused anesthetic present in the exhalation gas that the delivery unit 2 “reflects” back to the patient's airways 36 .
[0028] A second embodiment of an anesthetic delivery system is shown in FIG. 3 . A delivery unit 46 is configured with gas flow paths substantially similar to those illustrated in FIG. 1 and are again shown by arrows in the present figure. For ease of understanding items of the unit 46 of FIG. 3 that are substantially similar to items of the unit 2 of FIG. 1 are identified with corresponding reference numerals.
[0029] As described with respect to FIG. 1 , a port 6 a is provided in the unit 46 and delimits one end of a common flow passage 8 a . An anesthetic filter 48 is located with a first side in gas communication with the common flow passage 8 a and with a second, opposing, side for gas communication with a removable carbon dioxide filter 50 by means of a flow channel 12 . The carbon dioxide filter 50 , when inserted into the unit 46 (broken line construction of FIG. 2 ) through the co-operating access slot 52 , is also located in gas communication with a second common flow passage 8 b that is delimited at one end by a port 6 b in the unit 46 . A one-way valve 16 is disposed to prevent gas flow from the common flow passage 8 b into the carbon dioxide filter 50 .
[0030] The common flow passage 8 b also provides for gas communication between the port 6 b and a flow passage 28 that is arranged to communicate with the anesthetic filter 48 via an opening 24 in the common flow passage 12 . A one-way valve 30 ensures that gas can only flow in the flow passage 28 in a direction from the port 6 b.
[0031] Different from the embodiment of FIG. 1 , a bacteria filter 54 is located, optionally removably located, in the flow passage 28 to prevent contamination of the anesthetic filter 48 by bacteria that may be present in exhalation gas flowing into the unit 46 through the port 6 b.
[0032] Also different from the embodiment of FIG. 1 , the delivery unit 46 of FIG. 3 contains a housing 56 in which is held a charge 58 of anesthetic agent within a frangible container 60 . The housing 56 is provided with an opening 62 through which the charge 58 of anesthetic agent may flow to load the anesthetic filter 48 prior to use. The housing 56 is here also provided with internal walls 64 , shaped to funnel the flow of anesthetic agent towards the opening 62 . The housing 56 is further provided with an inwardly deformable wall section 66 that is accessible from external the delivery unit 46 . In use, an external force may be applied to this wall section 66 to cause its deformation and a consequent transmission of the force to the frangible container 60 . This results in the container 60 breaking to release the charge 58 . A removable rigid cover 68 is preferably provided to overlay the deformable wall section 66 to prevent accidental breakage of the container 60 . The housing 56 and the anesthetic filter 48 may be formed as a single unit, so as to be removable, within the delivery unit 46 .
[0033] A bypass gas flow passage 18 is connected for fluid communication with the common flow passage 8 a by an opening 20 and with the carbon dioxide filter 50 through the opening 24 in the flow passage 12 . Similar to the embodiment of FIG. 1 , a one-way valve 22 is provided to ensure that gas is able to flow through the bypass gas flow passage 18 only in the direction from the common flow passage 8 a , towards the carbon dioxide filter 50 . A vane 70 is provided within the passage 18 and is rotatable to present a variable resistance to gas flow from the common flow passage 8 a and thereby control the amount of gas bypassing the anesthetic filter 48 . The vane 70 is coupled to an anesthetic concentration sensor 72 via a linkage 74 . The rotational position of the vane 70 is automatically variable to change the flow resistance it presents dependent on the concentration of anesthetic that is sensed by the sensor 72 . In the present exemplary embodiment the concentration sensor 72 is formed of a silicone rubber block, a material that varies its physical dimensions in response to exposure to anesthetic, configured such that, in co-operation with the linkage 74 , it will exert a force on the vane 70 tending to cause the vane 70 to rotate and present a reducing resistance with increasing anesthetic concentration at the sensor 72 .
[0034] A part of third embodiment of an anesthetic delivery system according to the present invention is shown in FIG. 4 and shows an anesthetic absorption filter arrangement that may be employed as an alternative to those of FIG. 1 and FIG. 2 . In this third embodiment a membrane 76 replaces part of an external wall 78 of an anesthetic delivery unit 80 . The membrane 76 is of a type well known in the art of, for example implantable insulin pumps or of drug administration in ventilators, and is formed of a material that re-seals when a puncturing syringe needle is withdrawn. The membrane 76 of the present embodiment partially overlays and is presented here as being in intimate contact with an outer surface 82 of an anesthetic sorption filter 84 . A charge 86 of anesthetic agent is provided in a syringe 88 for injection through the membrane 76 and into an anesthetic receiving portion 84 b of the filter 84 to load at least part of the filter 84 with anesthetic agent for delivery to a patient. In this manner a region 84 a of the anesthetic filter 84 , which corresponds to that region 10 a of the filter 10 of the embodiment shown in FIG. 1 , may be provided that is initially substantially anesthetic free.
[0035] It will be appreciated that by using the combination of re-sealable membrane 76 and syringe 88 the sorption filter 84 may be optionally re-loaded during use. Moreover, this combination enables the filter 84 to be loaded immediately before use, which facilitates the storage of the anesthetic delivery system. Additionally the filter 84 may be loaded with an anesthetic agent of choice so that only a single construction type of delivery unit 80 needs to be manufactured.
[0036] Although modifications and changes may be suggested by those skilled in the art, it is the invention of the inventors to embody within the patent warranted heron all changes and modifications as reasonably and properly come within the scope of their contribution to the art.
|
An anesthetic delivery system has a delivery unit containing a carbon dioxide retaining element and a reversible action anesthetic absorber/desorber for releasably retaining therein at least a portion of a charge of anesthetic agent. An externally accessible first internal flow section in the delivery unit directs gas through the delivery unit first through the anesthetic absorber/desorber and then through the carbon dioxide retaining element, sequentially. An externally accessible second internal flow section directs gas through the delivery unit via the anesthetic absorber/desorber and bypassing the carbon dioxide retaining element.
| 0
|
CROSS REFERENCE TO RELATED PATENT APPLICATION
[0001] The present patent application claims the right of priority under 35 U.S.C. § 119 (a)-(d) of German Patent Application No. 102 48 618.2, filed Oct. 18, 2002.
FIELD OF THE INVENTION
[0002] The invention relates to solvent-free binder mixtures suitable for preparing two-component coating compositions, particularly for high-build applications, and to a process for preparing them.
BACKGROUND OF THE INVENTION
[0003] Prior art solvent-free coating systems can be divided roughly into two-component epoxy resin (2K EP) systems and two-component polyurethane (2K PU) systems.
[0004] Coatings based on 2K EP systems combine good mechanical strength with high resistance to solvents and chemicals. In addition they feature very good substrate adhesion. A distinct disadvantage is the poor elasticity of 2K EP coatings, particularly at low temperatures (e.g. in Kunststoff-Handbuch, Vol. 7; Polyurethane, 2 nd edition, G. Oertel (ed.), Hanser Verlag, Munich, Vienna, 1983, pp. 556-8). This brittleness leads to poor crack bridging by the coating, with the consequence that an attack on the substrate may occur here. An additional disadvantage is the very low stability to organic acids. This is a problem in particular for applications in the food sector, where organic acids are released as waste products.
[0005] A balanced combination of hardness and elasticity, in contrast, is the outstanding property of the 2K PU coatings and the greatest advantage over 2K EP coatings. Furthermore, with similar solvent and chemical resistances, the resistance to organic acids of 2K PU coatings is substantially better than 2K EP coatings.
[0006] For environmental reasons coating compositions ought to be solvent-free, particularly in the case of high-build applications, such as floor coatings for example. This means that the viscosity of the binder component ought to be low.
[0007] In high-build applications based on 2K PU systems the risk exists of blistering by the formation of CO 2 as a consequence of the water-isocyanate reaction. Consequently a very low water absorption of the raw materials is important in order that such coatings can be applied without blisters even in a damp environment. The hydroxy-functional component is generally more hydrophilic than the polyisocyanate component. It is therefore particularly important to employ hydrophobic hydroxy-functional components.
[0008] The hydroxy-functional binder component of the 2K PU coating may be based on a variety of types of chemical structure (e.g. Lehrbuch der Lacke und Beschichtungen, Vol. 2; pp. 205-209, H. Kittel, S. Hirzel Verlag, Stuttgart, Leipzig, 1998). Polyesterpolyols possess a low viscosity and feature a relatively low water absorption. The stability of the polyesterpolyols to hydrolysis, however, is low, thereby severely restricting the possibility of using them for corrosion prevention on metallic substrates and for coating mineral (alkaline) substrates. 2K PU coatings based on polyacrylate polyols feature good resistance to hydrolysis. A disadvantage here, however, is the relatively high viscosity level. Polyetherpolyols, in contrast, exhibit low viscosity and high stability to hydrolysis, but the high water absorption is a drawback.
[0009] EP-A 0 580 054 describes hydroxy-functional polyester-polyacrylate binders. These products exhibit a low viscosity and good mechanical strength in the 2K PU coatings produced from them. The stability to hydrolysis, however, is inadequate and the water absorption is too high for high-build applications in the floor coating or corrosion prevention sector.
[0010] EP-A 0 825 210 describes polyether acrylates. Although stable to hydrolysis and of low viscosity, these products too have a water absorption too high for high-build applications.
[0011] Sufficient hydrophobicity in solvent-free polyols is often achieved in the prior art through the use of castor oil. The 2K PU coatings produced with castor oil, however, are too soft for application in floor coating (e.g. Saunders, Frisch; Polyurethanes, Chemistry and Technology, Part 1 Chemistry pages 48 to 53, 314 and Part 2 Technology, chapter X).
[0012] An object of the present invention was therefore to provide a solvent-free binder mixture of low viscosity that is suitable for producing two-component systems, can be applied without blisters in high-build applications, and possesses sufficient hardness. Blister-free application presupposes a low water absorption, which at the same time should ensure an adequate pot life. The coatings produced with the binders of the invention ought further to possess good elasticity, chemical resistance and acid resistance.
SUMMARY OF THE INVENTION
[0013] The present invention is directed to a solvent-free binder mixture that includes a hydrophobic polyether polyacrylate (A), which includes the reaction product of (A1) a mixture of non-hydroxy-functional acrylic and styrenic monomers or copolymers thereof, (A2) hydroxy-functional polyethers, and optionally (A3) hydroxy-functional compounds having a molecular weight M n of from 32 to 1000 which are other than (A2). The solvent-free binder mixture has a water absorption of less than 8%, (measured after 21 days and at 23° C).
[0014] The present invention is further directed to a process for preparing the solvent-free binder mixture described above.
[0015] The invention is also directed to two-component polyurethane coating compositions containing the above-described solvent-free binder mixture as well as a metallic substrate or a mineral substrate coated by or using the present two-component polyurethane coating compositions.
DETAILED DESCRIPTION OF THE INVENTION
[0016] Other than in the operating examples, or where otherwise indicated, all numbers or expressions referring to quantities of ingredients, reaction conditions, etc. used in the specification and claims are to be understood as modified in all instances by the term “about.”
[0017] The object of the invention has been achieved by the provision of a binder mixture comprising a hydrophobic polyether polyacrylate based on non-hydroy-functional acrylic and styrenic monomers.
[0018] The invention provides solvent-free binder mixtures that include a hydrophobic polyether polyacrylate (A) which is a reaction product of:
[0019] (A1) a mixture of non-hydroxy-functional acrylic and styrenic monomers or copolymers thereof,
[0020] (A2) hydroxy-functional polyethers (A2),
[0021] (A3) if desired, hydroxy-functional compounds having a molecular weight M n of from 32 to 1000 which are other than (A2),
[0022] where the solvent-free binder mixture having a water absorption of less than 8%, in some cases less than 5% (measured after 21 days and at 23° C.).
[0023] In addition to the hydrophobic polyether polyacrylate (A) the binder mixtures of the invention can include a fatty alcohol (B), a non-limiting example of such being castor oil.
[0024] Likewise provided by the present invention is a two-component polyurethane coating composition that includes the binder mixture of the invention and a polyisocyanate (C), the NCO:OH equivalents ratio being between 0.5:1 to 2.0:1, preferably 0.8:1 to 1.5:1.
[0025] Suitable polyisocyanate components (C) include, but are not limited to organic polyisocyanates having an average NCO functionality of at least 2 and a molecular weight of at least 140 g/mol. In an embodiment of the invention, the polyisocyanate components (C) can be (i) unmodified organic polyisocyanates of the molecular weight range 140 to 300 g/mol, (ii) paint polyisocyanates with a molecular weight in the range from 300 to 1000 g/mol, and (iii) NCO prepolymers containing urethane groups and having a molecular weight of more than 1000 g/mol, or mixtures of (i) to (iii).
[0026] Non-limiting examples of polyisocyanates of group (i) are 1,4-diisocyanatobutane, 1,6-diisocyanatohexane (HDI), 1,5-diisocyanato-2,2-dimethylpentane, 2,2,4- and 2,4,4-trimethyl-1,6-diisocyanatohexane, 1-isocyanato-3,3,5-trimethyl-5-iso-cyanatomethyl-cyclohexane (IPDI), 1-isocyanato-1-methyl-4-(3)-isocyanato-methylcyclohexane, bis-(4-isocyanatocyclohexyl)methane, 1,10-diisocyanato-decane, 1,12-diisocyanatododecane, cyclohexane 1,3- and 1,4-diisocyanate, xylylene diisocyanate isomers, triisocyanatononane (TIN), 2,4-diisocyanato-toluene or its mixtures with 2,6-diisocyanatotoluene with preferably, based on mixtures, up to 35% by weight of 2,6-diisocyanatotoluene, 2,2′-, 2,4′-, 4,4′-, diisocyanatodiphenylmethane or technical-grade polyisocyanate mixtures of the diphenylmethane series, or any desired mixtures of the isocyanates stated. Preference is given in this case to employing the polyisocyanates of the diphenylmethane series, with particular preference in the form of isomer mixtures.
[0027] Non-limiting examples of the polyisocyanates of group (ii) include the paint polyisocyanates known per se. The term “coating polyisocyanates” in the context of the invention is used for compounds or mixtures of compounds which are obtained by conventional oligomerization reaction of simple diisocyanates of the type mentioned by way of example under (i). Examples of suitable oligomerization reactions include, but are not limited to carbodiimidization, dimerization, trimerization, biuretization, urea formation, urethanization, allophanatization and/or cyclization with the formation of oxadiazine structures. In the course of “oligomerization” it is often the case that two or more of the reactions stated run simultaneously or in succession.
[0028] In an embodiment of the invention, the “coating polyisocyanates” (ii) are biuret polyisocyanates, polyisocyanates containing isocyanurate groups, polyisocyanate mixtures containing isocyanurate and uretdione groups, polyisocyanates containing urethane and/or allophanate groups, or polyisocyanate mixtures containing isocyanurate and allophanate groups and based on simple diisocyanates.
[0029] The preparation of coating polyisocyanates of this kind is known and is described for example in DE-A 1 595 273, DE-A 3 700 209 and DE-A 3 900 053 or in EP-A-0 330 966, EP-A 0 259 233, EP-A-0 377 177, EP-A-0 496 208, EP-A-0 524 501 or U.S. Pat. No. 4,385,171.
[0030] In an embodiment of the invention, the polyisocyanates of group (iii) are the conventional isocyanato-functional prepolymers based on simple diisocyanates of the type exemplified above and/or based on coating polyisocyanates (ii) on the one hand and organic polyhydroxy compounds with a molecular weight of more than 300 g/mol on the other hand. Whereas the coating polyisocyanates of group (ii) which contain urethane groups are derivatives of low molecular weight polyols of the molecular weight range 62 to 300 g/mol—suitable polyols are, for example, ethylene glycol, propylene glycol, trimethylolpropane, glycerol or mixtures of these alcohols—the NCO prepolymers of group (iii) are prepared using polyhydroxyl compounds whose molecular weight is over 300 g/mol, preferably over 500 g/mol, more preferably between 500 and 8000 g/mol. Particular such polyhydroxyl compounds of this kind are those which contain per molecule from 2 to 6, preferably from 2 to 3, hydroxyl groups and are selected from the group consisting of ether, ester, thioether, carbonate, and polyacrylate poloyols and mixtures of such polyols.
[0031] In the preparation of the NCO prepolymers (iii) it is also possible for the relatively high molecular weight polyols stated to be employed in blends with the low molecular weight polyols stated, so leading directly to mixtures of low molecular weight paint polyisocyanates (ii) containing urethane groups and relatively high molecular weight NCO prepolymers (iii), which are likewise suitable as a starting component (C) according to the invention.
[0032] In an embodiment of the invention and in order to prepare NCO prepolymers (iii) or mixtures thereof with the coating polyisocyanates (ii), diisocyanates (i) of the type exemplified above or coating polyisocyanates of the type exemplified under (ii) are reacted with the relatively high molecular weight hydroxyl compounds or mixtures thereof with low molecular weight polyhydroxyl compounds of the type exemplified, observing an NCO/OH equivalents ratio of from 1.1:1 bis 40:1, preferably 2:1 to 25:1, with formation of urethanes. Optionally, using an excess of distillable starting diisocyanate, it is possible to remove this diisocyanate by distillation following the reaction, so that monomer-free NCO prepolymers, i.e. mixtures of starting diisocyanates (i) and true NCO prepolymers (iii), are obtained which may likewise be used as component (A).
[0033] The organic polyether polyacrylate component (A) has a hydroxyl group content of from 3.0 to 10% by weight, in some cases from 5.0 to 9% by weight, and a viscosity at 23° C. of from 200 to 3000 mPa.s, in some cases from 400 to 2800 mPa.s.
[0034] In an embodiment of the present invention, Component (A) is prepared by free-radical addition polymerization of
[0035] (A1) from 10 to 50 parts by weight, preferably from 15 to 40 parts by weight of a mixture of non-hydroxy-functional acrylic and styrenic monomers or copolymers thereof, the fraction of styrene monomer being from 10 to 80%, preferably from 20 to 50%, based on component (A1),
[0036] (A2) from 15 to 90 parts by weight, preferably from 20 to 85 parts by weight of one or more hydroxy-functional polyethers having an OH functionality of greater than or equal to 2, and
[0037] (A3) from 0 to 50 parts by weight of hydroxy-functional compounds having a molecular weight M n of from 32 to 1000 which are other than (A2), the mixture of (A2) and (A3) including at least 30 parts by weight of (A2),
[0038] in the presence of polymerization initiators (D) and also, optionally, further auxiliaries and additives.
[0039] Following the polymerization from 0 to 80 parts by weight, preferably from 10 to 60 parts by weight, of fatty alcohols (B), a non-limiting example of which being castor oil, are added.
[0040] The monomers (A1) are monounsaturated compounds of the molecular weight range from 50 to 400 g/mol, in some cases from 80 to 220 g/mol. The non-hydroxy-functional acrylates include for example acrylic or methacrylic alkyl or cycloalkyl esters having 1 to 18, in some cases 1 to 8 carbon atoms with alkyl, cycloalkyl radical such as, for example, methyl, ethyl, n-propyl, n-butyl, isopropyl, isobutyl, t-butyl, the isomeric pentyl, hexyl, octyl, dodecyl, hexadecyl or octadecyl esters of the stated acids, acetoacetoxyethyl methacrylate, acrylonitrile or methacrylonitrile. Instead of styrene it is also possible to use vinyltoluene. Mixtures of the monomers can also be used. Advantageous monomers (A1) that can be used in the invention include, but are not limited tostyrene, methyl methacrylate and butyl acrylate.
[0041] Suitable hydroxy-functional components (A2) include monohydric or polyhydric alcohols of the molecular weight range from 108 to 2000 g/mol, in some cases from 192 to 1100 g/mol, which contain ether groups, or mixtures of such alcohols. Preference is given to polyetherpolyols having 2 or more hydroxyl groups per molecule, such as are obtainable conventionally by addition reaction of cyclic ethers, such as propylene oxide, styrene oxide, butylene oxide or tetrahydrofuran, with starter molecules such as water, polyhydric alcohols free of ether groups, amino alcohols or amines. Particular preference is given to polyethers composed of at least 50%, preferably at least 90%, based on the sum of their repeating units, of repeating units of the structure —CH(CH 3 )CH 2 O—.
[0042] Suitable starter molecules for this purpose include, but are not limited to polyhydric alcohols such as for example ethylene glycol, propane-1,2- and -1,3-diol, butane-1,2-, 1,3-, -1,4- and -2,3-diol, pentane-1,5-diol, 3-methylpentane-1,5-diol, hexane-1,6-diol, octane-1,8-diol, 2-methylpropane-1,3-diol, 2,2-dimethly-propane-1,3-diol, 2-ethyl-2-butylpropane-1,3-diol, 2,2,4-trimethylpentane-1,3-diol, 2-ethylhexane-1,3-diol, relatively high molecular weight α,ω-alkanediols having 9 to 18 carbon atoms, cyclohexanedimethanol, cyclohexanediols, glycerol, trimethylolpropane, butane-1,2,4-diol, hexane-1,2,6-triol, bis(trimethylolpropane), pentaerythritol, mannitol or methyl glycoside. Preference is given to the starters with a functionality of three or more such as for example trimethylolpropane, glycerol, hexanetriol, pentaerythritol, 2-aminoethanol, ethylenediamine with ethers based on propylene oxide or tetrahydrofuran.
[0043] Non-limiting examples of suitable amino alcohols include 2-aminoethanol, 2-(methylamino)ethanol, diethanolamine, 3-amino-1-propanol, 1-amino-2-propanol, diisopropanolamine, 2-amino-2-hydroxymethyl-1,3-propanediol or mixtures thereof.
[0044] Particularly suitable polyfunctional amines include, but are not limited to aliphatic or cycloaliphatic amines, such as ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,3-diamino-2-2-dimethylpropane, 4,4-diaminodicyclohexylmethane, isophoronediamine, hexamethylenediamine, 1,12-dodecanediamine or mixtures thereof.
[0045] In addition to the polyetherpolyols described, having a functionality of two or more, it is also possible where appropriate to use monohydroxy polyethers alone or as a mixture with polyetherpolyols of higher functionality. Monohydroxy polyethers can be obtained in analogy to the abovementioned polyetherpolyols by addition reaction of the abovementioned cyclic ethers with monoalcohols, especially linear or branched aliphatic or cycloaliphatic monohydroxyalkanes, such as methanol, ethanol, propanol, butanol, hexanol, octanol, 2-ethylhexanol, cyclohexanol or stearyl alcohol, for example, or secondary aliphatic or cycloaliphatic monoamines, such as dimethylamine, diethylamine, diisopropyl-amine, dibutylamine, N-methylstearylamine, piperidine or morpholine, for example. Particular preference, however, is given to using polyetherpolyols of relatively high functionality, especially those having 2 or 3 hydroxyl groups per polyether molecule.
[0046] It is likewise possible for preparing component (A) to use hydroxy compounds of molar weight 32 to 1000 g/mol having a functionality of at least 2 as component (A3). In this embodiment of the invention, use is made of low molecular weight hydroxy compounds of molecular weight 32 to 350 g/mol, such as -1,2-, -1,3-, -1,4- and -2,3-diol, pentane-1,5-diol, 3-methylpentane-1,5-diol, hexane-1,6-diol, 2-ethylhexane-1,3-diol, 2-methylpropane-1,3-diol, 2,2-dimethylpropane-1,3-diol, 2-butyl-2-ethylpropane-1,3-diol, 2,2,4-trimethylpentane-1,3-diol, octane-1,8-diol, relatively high molecular weight α,ω-alkanediols having 9 to 18 carbon atoms, cyclohexanedimethanol, cyclohexanediol, glycerol, trimethylolpropane, butane-1,2,4-triol, hexane-1,2,6-triol, bis(trimethylolpropane), pentaerythritol, mannitol or methyl glycoside. The hydroxypolyesters, hydroxypolyesteramides, hydroxypolycarbonates or hydroxypolyacetals known per se from polyurethane chemistry, up to a molecular weight of 1000 g/mol, may likewise be employed.
[0047] Suitable fatty alcohols (B) are compounds containing one or more hydroxyl groups. The hydroxyl groups can be joined to saturated, unsaturated, unbranched or branched alkyl radicals having more than 8, in particular more than 12, carbon atoms. They may contain further groups such as, for example, ether, ester, halogen, amide, amino, urea, and urethane groups. Specific examples are castor oil, 12-hydroxystearyl alcohol, oleyl alcohol, erucyl alcohol, linoley alcohol, linolenyl alcohol, arachidyl alcohol, gadoleyl alcohol, erucyl alcohol, brassidyl alcohol or dimerdiol (=hydrogenation product of dimer fatty acid methyl ester), preference being given to castor oil.
[0048] In the preparation of the polyether polyacrylate component (A) containing in the binder mixture of the invention the weight ratio of component (A1) to the sum of component (A2 and A3) is from 10:90 to 50:50, preferably from 15:85 to 40:60, the weight ratio of component (A2) to component (A3) being between 30:70 and 100:0, and the weight ratio of the sum of components (A1), (A2) and (A3) to component (B) is from 100:0 to 20:80, preferably from 100:0 to 40:60.
[0049] The polyether polyacrylate (A) can be prepared in a feed technique by a free-radical polymerization which is known per se and is described for example in EP-A-580 054. Generally speaking at least 50% by weight of component (A2), preferably 100% by weight, are charged to the polymerization vessel and heated to the reaction temperature, which is from 80 to 220° C. Subsequently the monomer mixture (A1), fractions of components (A2) and (A3) where appropriate, and a polymerization initiator (D) are metered in. After the end of the addition the reaction is completed by subsequent stirring at a temperature which is from 0 to 80° C., preferably 0 to 50° C., below the original reaction temperature. Component (B) is added only after the polymerization has reached an end.
[0050] The invention also provides a process for preparing the binder mixture of the invention, characterized in that component (A2) is introduced initially and heated and then the monomer mixture (A1), where appropriate with fractions of components (A2) and (A3), and a polymerization initiator (D) are metered in and polymerized. Preferably the fatty alcohol (B) is added subsequently.
[0051] Examples of suitable polymerization initiators (D) include, but are not limited to dibenzoyl peroxide, di-tert-butyl peroxide, dilauryl peroxide, dicumyl peroxide, didecanoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl perpivalate or butyl peroxybenzoate and also azo compounds, e.g. 2,2′-azobis(2,4-dimethyl-valeronitrile), 2,2-azobis-(isobutyronitrile), 2,2′-azobis(2,3-dimethylbutyronitrile), 1,1′-azobis-(1-cyclohexanenitrile). Other industrially available free-radical initiators can also be employed. Preference is given to the peroxides, particular preference to dicumyl peroxide and di-tert-butyl peroxide.
[0052] It may be necessary by subsequent addition of small amounts of initiator to perform a reactivation in order to achieve complete monomer conversion. If in exceptional cases an inadequate conversion is found after the reaction has been terminated, and relatively large amounts of starting compounds are still present in the reaction mixture, they can either be removed by distillation or brought to reaction by further reactivation with initiator accompanied by heating at reaction temperature.
[0053] In the preparation of the polyether polyacylate (A) it is possible where appropriate to use auxiliaries and additives as well, such as molecular weight regulator substances, e.g. n-dodecyl mercaptene, tert-dodecyl mercaptan or the like, the α-olefins with low polymerization tendency that are described in EP-A 471 258 (page 5, lines 24-36) and the derivatized dienes described in EP-A 597 747 (page 1, lines 40-58m page 3 lines 1-11) employed. These compounds are used in amounts of up to 20% by weight, preferably up to 10% by weight, based on the total weight of component (A).
[0054] If desired the antioxidants and/or light stabilizers known in coating technology can be added as stabilizers to the solvent-free binder mixtures of the invention in order to achieve further improvement in the light stability and weather stability of the polyether polyacrylates (A). With preference, however, the coating compositions of the invention are used in stabilizer-free form.
[0055] Examples of suitable antioxidants include sterically hindered phenols such as 4-methyl-2,6-di-tert-butylphenol (BHT) or other substituted phenols (Irganox® series, Ciba Geigy, Basle), thioethers (e.g. Irganox® PS, Ciba Geigy, Basle) or phosphites (e.g. Irgaphos®, Ciba Geigy, Basle).
[0056] Examples of suitable light stabilizers include “HALS” amines (Hindered Amine Light Stabilizers) such as Tinuvin® 622D or Tinuvin® 765 (Ciba Geigy, Basle), for example, and also substituted benzotriazoles such as Tinuvin® 234, Tinuvin® 327 or Tinuvin® 571 (Ciba Geigy, Basle), for example.
[0057] To prepare the coating compositions comprising the binder mixtures of the invention components (A) and (C) are mixed with one another in proportions such that the NCO:OH equivalents ratio corresponds to from 0.5:1 to 2.0:1, preferably from 0.8:1 to 1.5:1. During or after this mixing of the individual components it is possible if desired to admix the customary auxiliaries and additives of coating composition technology. These include, for example, levelling agents, viscosity regulator additives, pigments, fillers, dulling agents, UV stabilizers and antioxidants, and also catalysts for the crosslinking reaction.
[0058] The coating compositions comprising the binder mixtures of the invention are used to produce solvent-free two-component polyurethane coatings. These coatings have a Shore D hardness of at least 50 (DIN 53505).
[0059] The present application likewise provides solvent-free two-component polyurethane coatings comprising the binder mixtures of the invention.
[0060] It is preferred to use the binder mixtures of the invention to produce coatings for protecting metallic substrates against mechanical damage and corrosion and also for protecting mineral substrates, such as concrete, for example, against environmental effects and mechanical damage. The coat thickness lies in the range from 0.5 to 10 mm, preferably from 0.7 to 6 mm.
[0061] Likewise provided by the present invention are substrates coated with coating compositions comprising solvent-free binder mixtures of the invention.
EXAMPLES
Components Employed
[0062] Desmodur® VL: 4,4′-diphenylmethane diisocyanate-based polyisocyanate having an NCO content of 31.5% and a viscosity at 23° C. of 90 mPa.s, Bayer AG, Leverkusen
[0063] Desmophen® 550U: propylene oxide-based branched polyether having a number-average molecular weight of 437 g/mol, a viscosity at 23° C. of 55 mPa.s and an OH content of 11.7%, Bayer AG, Leverkusen
Examples 1 to 6
[0064] General working instructions for preparing the polyether polyacrylates:
[0065] Part 1:
Desmophen ® 550U 56.2 (g)
[0066] Part 2:
Methyl methacrylate 7.5 (g) Styrene 7.5 (g) Butyl acrylate 1.9 (g)
[0067] Part 3:
Di-tert-butyl peroxide 1.9 (g)
[0068] Part 4:
Castor oil 25 (g)
[0069] The components from part 1 are heated to 165° C. in a reaction vessel with stirring. Over the course of 3 hours part 2 is metered in continuously and part 3 is metered in continuously in parallel therewith over the course of 3.5 hours. After 3 hours the addition of part 3 is interrupted and the mixture is cooled to 140° C. After the temperature has cooled to 140° C. the remainder of part 3 is metered in. After a further 2 hours at 140° C. the product is cooled to room temperature and, where appropriate, part 4 is admixed.
[0070] The composition of the products and also the OH content, viscosity and water absorption are given in Table 1.
TABLE 1 Composition and key data of polyether polyacrylates Example (inventive) 1 2 3 4 5 6 (Comparative) 7 Desmophen ® 550U (g) 75 70.00 60 56.25 37.5 18.75 75 Styrene (g) 10 9.00 8.00 7.5 5 2.5 10 Methyl methacrylate (g) 10 9.00 8.00 7.5 5 2.5 — Hydroxymethyl methacrylate (g) — — — — — — 10 Butyl acrylate (g) 2.5 2.25 2.00 1.875 1.25 0.625 — Hydroxymethyl acrylate (g) — — — — — — 2.5 Di-tert-butyl peroxide (g) 2.5 2.25 2.00 1.875 1.25 0.625 2.5 Castor oil (g) 0 0 0 25 50 75 0 Key data Viscosity, 23° C., mPa · s 2600 2190 1815 1515 1086 872 5880 OH content (%) 8.7 8.4 8.0 7.8 6.9 5.9 10.8 Water absorption after 21 days, 7.7 6.9 5.8 4.1 2.3 1.1 10.6 23° C. (%) a # absorption was calculated in accordance with the following formula: Water absorption = weight increase * 100/initial weight (%)
Example 10 to 18
[0071] General working instructions for preparing the binder mixtures and their use:
[0072] The polyisocyanate and the polyether polyacrylate are admixed where appropriate with catalyst and additives and mixed to homogeneity. The binder mixture is then applied to the test substrate. The composition and the final Shore D hardness are given in Table 2.
TABLE 2 Composition and final Shore D hardness of the binder mixtures Example 10 11 12 13 14 15 16* Example 1 100 Example 2 100 Example 3 100 Example 4 100 Example 5 100 Example 6 100 Example 7 100 Desmodur ® VL c 71.6 69.2 67.5 64.2 56.8 48.6 88.9 NCO:OH eq. ratio 1.05:1 1.05:1 1.05:1 1.05:1 1.05:1 1.05:1 1.05:1 Processing time a 60 60 60 60 60 60 30 (min) Shore D hardness to 75 75 75 75 65 50 75 DIN 53505
[0073] The inventive examples (1-6) possess a low water absorption in combination with a low viscosity and at the same time exhibit a high hardness in the coating. Example 7 exhibits a high water absorption and viscosity. On addition of castor oil the mixture from Example 7 becomes cloudy.
[0074] Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims.
|
The invention relates to solvent-free binder mixtures suitable for preparing two-component coating compositions, particularly for high-build applications, and to a process for preparing them.
| 2
|
FIELD OF THE INVENTION
[0001] This invention relates to anchors. In particular, this invention relates to portable ground anchors for use in extracting vehicles from a trapped position by means of a winch.
BACKGROUND OF THE INVENTION
[0002] Vehicles which travel off road, on unpaved surfaces or on weather covered streets are often subject to traps which prevent desired travel in the vehicles, These vehicles may encounter mud, snow, sand or other traps in which vehicle tires are deprived of significant friction against a solid surface. Without sufficient friction against a solid surface, vehicle tires are unable to provide adequate traction to propel the vehicle in motion and free it from the mire. A winch is a useful tool for freeing trapped vehicles from earthen traps. In order to free a trapped vehicle, a winch is situated between a nearby stationary object and the vehicle to be removed from the trap. One end of the winch is connected by cable, rope, chain or other line device to the nearby stationary object. The other end of the winch is either attached to the vehicle or connected to the vehicle by cable, rope, chain or other line device. Pulley action within the winch shortens the total length of line between the vehicle and the stationary object, and assists the trapped vehicle in freeing itself from the trap.
[0003] A problem may arise for vehicles that become trapped in an area void of stationary objects such as trees, fenceposts, buildings, or other fixed structures. Without a stationary object, the line and winch has nothing to pull against, and the vehicle will remain trapped in the mire.
[0004] Ground anchors are useful in freeing vehicles from the confines of snow, mud, sand or other traps when there are no stationary objects in the near vicinity to the trapped vehicles. Ground anchors provide the necessary ground gripping action to pull a vehicle from mire when there are no stationary objects in the nearby vicinity.
[0005] Ground anchors of various types have been previously described as exemplified in U.S. Pat. Nos. 4,825,604 to Manning, 4,026,080 to Meikle and 3,500,589 to Ettinger. However, previous ground anchors have provided insufficient ground gripping when heavyduty vehicles must be removed from deep mire. Larger ground anchors are helpful in providing additional strength, but may be inconveniently bulky to haul and use. Additionally, many ground anchors are difficult to use or require substantial efforts to remove from the ground.
[0006] Therefore, it is an object of the invention to provide a portable ground anchor of sufficient strength that heavy-duty loads may be applied to the anchor. Another object of the invention is to provide a portable ground anchor that is collapsible so that it may be easily hauled in a vehicle. It is a further object of the invention to provide a portable ground anchor that may be easily assembled, is convenient and simple to use, and requires little effort to remove from the ground and disassemble after use.
SUMMARY OF THE INVENTION
[0007] The present invention relates to an improved ground anchor system for anchoring one end of a cable to the ground. The improved ground anchor system comprises a pair of hingedly attached, ground engaging base plates supporting a pair of vertically extending, pivoting central plates which are horizontally joined by one or more cable attachment bars. The base plates may be removably affixed to uneven or sloping ground by several long spikes or rods to provide a firm, but temporary and reusable anchor for a vehicle's winch cable.
[0008] The ground anchor system is easily collapsed and stored in a vehicle so that it may be used upon demand. Furthermore, the ground anchor system is quickly and easily assembled for use and, upon assembly, provides sufficient strength that heavy loads may be supported by the anchor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a side plan view of one embodiment of an improved ground anchor system in accordance with the present invention;
[0010] FIG. 2 is a side plan view of the improved ground anchor system illustrated in FIG. 1 , rotated about 90° from the viewing angle of FIG. 1 ,
[0011] FIG. 3 is a top plan view of a first and a second base member of the improved ground anchor system taken substantially along line 3 - 3 in FIG. 1 ;
[0012] FIG. 4 is a side plan view of a central member of the improved ground anchor system illustrated in FIG. 1 ;
[0013] FIG. 5 is a plan view of a retention pin of the improved ground anchor system.
[0014] FIG. 6A is a side partial plan view of the first base member of the improved ground anchor system illustrated in FIG. 1 .
[0015] FIG. 6B is an end view of the first base member taken substantially alone line 6 B- 6 B in FIG. 6A .
DETAILED DESCRIPTION OF THE INVENTION
[0016] Referring to FIG. 1 , 2 and FIG. 3 , an improved ground anchor system 1 comprises a first base member 2 , a second base member 4 , a first central member 6 , a second central member 8 , spacers 10 , a hinge pin 12 , retainer clips 14 , and ground spikes 16 .
[0017] The first base member 2 comprises a steel plate being about 10 inches wide, about 12 inches in length, and about 1 inch in thickness. Referring to FIG. 3 , the first base member 2 includes a front portion 20 , a rear edge 22 , side edges 23 and 25 , first indented portion 26 adjacent side edge 23 of member 2 , second indented portion 28 adjacent side edge 25 of member 2 . A hinge member 24 extends outwardly from front portion 20 , and spike holes 30 extend at various locations through base member 2 .
[0018] The second base member 4 also comprises a steel plate about 10 inches wide, about 12 inches in length, and about 1 inch in thickness. The second base member 4 comprises a front portion 32 , a rear edge 34 , side edges 33 and 35 , a first indented portion 38 adjacent side edge 33 , and a second indented portion 40 adjacent side edge 35 . A first hinge 42 and a second hinge 44 are formed on and extend outwardly from front portion 32 . A female slot 36 is formed between first and second hinges 32 and 34 to receive hinge member 24 . Spike holes 30 extend at various locations through base member 4 .
[0019] With reference to FIGS. 6A and 6B , hinge member 24 is formed by bending an extending portion of front portion 20 into a circle to form a circular channel 27 dimensioned to freely receive hinge pin 12 . Hinge members 42 and 44 are similarly formed by bending extending portions of front portion 32 into a circle to form a circular channel dimensioned to freely receive hinge pin 12 . The hinge member 24 is placed into female slot 36 so that the circular channel 27 of hinge member 24 aligns with the circular channels in hinge members 42 and 44 , and thus hinge pin 12 can be inserted through the channels so that first base member 2 and second base member 4 become pivotally connected.
[0020] Ground spikes 16 are typically formed from cylindrical steel and are about 24 inches in length. The diameter of spikes 16 is slightly less that the diameter of spike holes 30 so that the spikes 16 can be inserted into holes 30 and pounded into the ground to secure the first base member 2 and the second base member 4 in a fixed position upon the ground.
[0021] The hinge pin 12 comprises a steel shaft of about 12 inches in length and about ¾ inches in diameter. The hinge pin 12 further comprises small circular openings (not shown) drilled through hinge pin 12 at opposing ends and dimensioned to receive retainer clips 14 . The retainer clips 14 ( FIG. 5 ) may be inserted into the small circular openings in hinge pin 12 to prevent the hinge pin 12 from moving out of the circular channels in hinge members 24 , 42 , and 44 .
[0022] Referring to FIGS. 1 , 2 and 4 , central assembly 7 is pivotally joined to the assembly by hinge pin 12 extending through openings 50 at apexes 48 of central members 6 and 8 . The first central member 6 and second central member 8 each comprise a triangular shaped plate of steel 46 (see FIG. 4 ), each having a width of about 5 inches at a base 51 , a height of about 8⅜ inches along edges 53 and 55 , and a thickness of about 1 inch. The first central member 6 and second central member 8 each further comprise a triangular apex 48 , a circular opening 50 , and spacer attachment openings 52 . The circular openings 50 of the first central member 6 and the second central member 8 are dimensioned slightly larger than hinge pin 12 so that hinge pin 12 can be freely inserted therethrough. Central assembly 7 is formed by placing the ends of spacers 10 into attachment openings 52 and retaining them by welding or other suitable means of attachment so that central members 6 and 8 are retained in a spaced apart relationship such that the apexes 48 will extend into indented portions 26 , 28 , 38 and 40 of base members 2 and 4 . Spacers 10 could also be threaded at each end and attached by using nuts on each side of members 6 and 8 to facilitate disassembly. The spacers 10 also provide a means to attach a winch cable 54 to the improved ground anchor 1 . Additionally, the spacers 10 permit the central assembly 7 to pivot around hinge pin 12 , and also add structural strength to the assembly.
[0023] To assemble the combination, the first base member 2 and the second base member 4 are positioned so that the hinge member 24 is between hinges 42 and 44 in slot 36 so that the circular channels align. Central assembly 7 is positioned so that the openings 50 also align with the circular channels in the hinge members. Hinge pin 12 is inserted through openings 50 and the circular channels 27 and retainer clips 14 are placed through the openings in the hinge pin 12 to lock the hinge pin in place. The ground spikes 16 can be inserted into the spike holes 30 in first base member 2 and second base member 4 to position the spikes 16 to be driven into the ground.
[0024] Operation of the improved ground anchor system 1 is now described. Once the assembly has been completed, the improved ground anchor system 1 is place at the desired ground location. Preferably, the base members should be oriented such that the hinge pin 12 is parallel to the bumper of the trapped vehicle and perpendicular to the force vector to be applied by the cable. Ground spikes 16 are pounded into the ground though the spike holes 30 to secure the first base member 2 and the second base member 4 to a fixed position against the earth.
[0025] After anchoring the invention to the earth, the improved ground anchor system 1 may be used to free trapped vehicles from earthen mire, With the hinge pin 12 oriented approximately perpendicular to the cable 54 to be attached to the trapped vehicle, the central assembly 7 can be pivoted toward the trapped vehicle as shown by the dotted lines in FIG. 1 . A winch (not shown) and cable 54 is used to link the trapped vehicle (not shown) to one or more of the spacers 10 of the improved ground anchor system. One end of a winch cable 54 is connected to the present invention 1 at a spacer 10 , and the other end of the winch and cable system is connected to the trapped vehicle. After the central assembly 7 is pivoted toward the trapped vehicle, the winch is operated to remove slack in the winch cable 54 and pull the cable taut. As the vehicle attempts to drive out of the mire, additional slack in the winch cable 54 is removed by operation of the winch until the vehicle is freed. By use of a winch and cable, the improved ground anchor system 1 is capable of assisting trapped vehicles and freeing them from mire.
[0026] As may be seen, as force is applied to cable 54 , central assembly 7 pivots toward the mired vehicle thus bringing the line of force being applied along cable 54 closer to the plane of base members 2 and 4 . This increases the effectiveness of the anchor because the force applied is closer to the base members 2 and 4 making the force on the ground spikes 16 more in shear because the moment arm of the system is substantially reduced. Further, because base members 2 and 4 are pivotally connected at hinge pin 12 , the point at which the pulling force is applied to the assembly, any upward force on the pin 12 created by the moment arm of central assembly 7 tends to cause a downward force at the edge 22 of first base member 2 and edge 35 of second base member 4 thereby tending to cause the spikes 16 in first base member 2 to squeeze toward the spikes 16 in second base member 4 thereby tending to hold the spikes 16 more firmly in the ground. Thus, the present anchor is far more effective than if a single unitary base member were used.
[0027] It will be appreciated by those skilled in the art that the present invention is capable of easy assembly and disassembly, and that upon disassembly, it may be conveniently carried in any vehicle.
[0028] It will be further appreciated by those skilled in the art that the present invention may be fixed to the ground for other purposes such as to secure an airplane against the wind or a boat to the shore. Further the anchor of the present invention is useful for any purpose requiring a strong stationary ground anchor.
|
A portable ground anchor system comprises base plate members having a hinge pin passage formed therethrough and each base plate member having a multiplicity of holes formed therethrough for interaction with ground spikes; central triangular shaped plate members having circular openings formed therethrough at a triangular apex thereof; a spacer member adapted to provide an engagement for a cable, said spacer member interconnected between said central triangular shaped plate members; a cylindrical pin for pivotally joining the base plate members and the central triangular members.
| 4
|
BACKGROUND OF INVENTION
[0001] This patent relates to a method of making a dry bonded paperboard structure. More particularly, this patent relates to a method of making a spirally wound paperboard container in which a radio frequency active adhesive is added to the pulp stock during the paperboard fabrication process.
[0002] Paperboard is one of two broad subdivisions of paper (general term), the other being paper (specific term). The distinction between paper and paperboard is not sharp, but, broadly speaking, paperboard is heavier, thicker, and more rigid than paper. For the purposes of this patent, the term “paper” shall include paperboard and the term “paperboard” shall include paper.
[0003] Paperboard can be used to make numerous structures, including spirally wound structures such as tubes, cores and cylindrical containers. In the manufacture of spirally wound containers, a web of paperboard is fed at a desired angle to a stationary mandrel to form the structural or bodywall layer of the container. Prior to being wound, a permanent heat sensitive adhesive is applied by a roller along a marginal edge of the paperboard web. The web is passed under a heater that softens the adhesive and makes it tacky. As the web is wound around the mandrel, the first marginal edge of the web advances back under the mandrel and is brought into contact with the opposing edge of the ensuing portion of the web. The edges become adhered to form a spirally wound tube, which can then be cut into desired lengths.
[0004] The heat sensitive adhesive is usually aqueous based, of which a few examples are vinyl acetate/ethylene copolymers, polyvinyl alcohol, polyvinyl acetate (a.k.a. “white glue”), dextrin, casein and acrylics. The problem with using aqueous based adhesives is that the water from the adhesive can migrate into the paperboard, potentially decreasing the mechanical properties of the paperboard, such as compression strength, tensile strength, tearing strength and folding endurance.
[0005] Drummond et al. U.S. Pat. No. 6,296,600 discloses a method of reducing the migration of water into the paperboard by using a foamed adhesive, which reduces the amount of adhesive that comes into contact with the paperboard. While this solution may be effective, there still exists a need for a method of making paperboard containers that reduces or eliminates the amount of water migrating into the paperboard and at the same time strengthens the paperboard.
[0006] This need is solved by the present invention through the use of radio frequency (RF) active adhesives and RF heating. As is well known in the art, radio frequency heating is a method used to generate heat directly within a material containing RF active components (susceptors), and indirectly within materials that are in thermally conductive contact with RF susceptors. RF susceptors are ionic or polar materials that have the ability to convert RF energy into thermal energy when exposed to an RF electromagnetic or electrical field.
[0007] As disclosed in International Patent Application Nos. WO 99/47621 and WO 01/21725,RF active adhesives (adhesives containing RF susceptors) can be used to adhere two or more layers of non-conducting substrates. Adhesion is accomplished by exposing an adhesive layer between the substrates to radio frequency energy in the range of from about 1 MHz to about 100 MHz, which induces dielectric current in the RF susceptor. The current generates thermal energy, which causes the adhesive to soften and adhere the adjoining substrates.
[0008] These and other patents describe methods of bonding adjacent substrates by coating one or both substrates with an RF active adhesive. What is heretofore not known is that two or more paperboard layers can be bonded by adding RF active adhesive to the paperboard pulp stock during the paperboard making process.
[0009] Thus it is an object of the present invention to provide a method of making a paperboard structure that reduces or eliminates the amount of water migrating into the paperboard.
[0010] Another object of the invention is to provide a method of making a spirally wound paperboard structure that eliminates the step of coating the paperboard web with adhesive prior to winding.
[0011] Yet another object of the invention is to provide a method of making a spirally wound paperboard structure that uses an RF active compound for adhesion.
[0012] Still another object of the invention is to provide a method of making a multiple ply paperboard suitable for dry bonding in which an RF active adhesive is added to the outer plies of the paperboard but not the inner plies.
[0013] Further and additional objects will appear from the description, accompanying drawings, and appended claims.
SUMMARY OF INVENTION
[0014] The present invention is a method of making a dry bonded paperboard structure by adding an RF active adhesive to the pulp stock during the making of the paperboard. The method comprises the steps of adding a radio frequency active adhesive to paperboard pulp stock; forming the pulp stock into a web or sheet; exposing the sheet to RF energy to generate heat sufficient to cause the adhesive in the sheet to soften; arranging one or more of the sheets in at least partially overlapping relationship; and allowing the adhesive to harden, thereby forming the multiple-ply paperboard structure. The method may be used to make spirally wound tubular structures such as tubes, cores and cylindrical containers. By eliminating the need to coat the paperboard with aqueous adhesive, the method reduces or eliminates the migration of water into the paperboard, thereby producing a stronger paperboard structure.
[0015] In an alternative embodiment, the paperboard comprises multiple plies, and the adhesive is added only to the pulp stock that is used to make the outer ply or plies.
DETAILED DESCRIPTION
[0016] The present invention is a method of making a dry bonded paperboard structures, especially spirally wound paperboard structures, by exploiting radio frequency heating technology. The method eliminates the step of coating the paperboard with an aqueous-based adhesive, thus the term “dry bonded.” The method also serves to strengthen the paperboard by impregnating it with a radio frequency (RF) active adhesive.
[0017] In a key aspect of the invention, the RF active adhesive is added to pulp stock that is used to make the paperboard. The adhesive impregnated paperboard web is exposed to RF energy just prior to winding, softening the adhesive and allowing the layers of paperboard to bond to each other. After forming the sheet into the desired structure, the adhesive is allowed to set.
[0018] The method may be thought of as comprising the following steps: i. adding a radio frequency (RF) active adhesive to pulp stock; ii. forming the pulp stock into a paperboard sheet and allowing the sheet to dry; iii. exposing the adhesive-impregnated paperboard sheet to RF energy to generate heat sufficient to cause the adhesive in the sheet to soften; iv. arranging (winding) the sheet to form a paperboard structure; and v. allowing the adhesive to harden.
[0019] The mechanical properties of the paperboard, and thus the paperboard structure, depend on the type of adhesive used. One possible adhesive is polyvinyl acetate (PVA) dispersed or dissolved in a liquid carrier media. PVA has a dipole at the vinyl group that renders it RF active. Other possible adhesives include phenolic resins such as phenol-formaldehyde resin, ethyl vinyl acetate (EVA), melaminic resins such as melamine-formaldehyde resin, polyethylene terpthatate (PET), and silicates, although any suitable RF active adhesive or combination of adhesives may be used.
[0020] Although the adhesive of the present invention has been described as being “RF active”, it is to be understood that the adhesive may be activated by electromagnetic radiation having a frequency extending beyond the radio region (typically 3 Hz to 1 GHz) and into the microwave region (typically 3 GHz to 3 THz).
[0021] The primary benefit of the method is eliminating the step of coating the paperboard with water-based adhesive prior to winding and the associated migration of water into the paperboard. The invention also makes it easier to completely wet the paperboard fibers, since the RF active adhesive is distributed evenly throughout the paperboard, not just on the outer surface of the paperboard sheet. This further improves the mechanical properties of the paperboard, since paperboard has a relatively low, out-of-plane strength and modulus. The resulting paperboard has an enhanced flexural stiffness.
[0022] The invention works in the following manner. In the pulping stage of paper and paperboard making, cellulous fibers from wood and/or other sources are separated from each other and from other impurities such as lignin by either chemical or mechanical means, or a combination of both. Chemical pulping generally provides a pulp that is stronger and thus better suited for production of board grades where strength is important. Kraft paper is produced from a chemical pulping process known as the kraft process, in which the fibrous material is cooked in a solution of caustic soda. In German, the word “kraft” means “strength”. Mechanical pulping produces a high-yield pulp with high opacity and bulk, suitable for use as newsprint and other grades where these characteristics are desired. The present invention may be used with any type of pulping means.
[0023] The product of the pulping stage is a paste-like liquid referred to as pulp stock or furnish. Prior to being made into paper or paperboard, the pulp stock may be further treated to shape the fibers and remove any remaining contaminants. Chemical strength additives may be added to the pulp stock to improve fiber bonding. Other additives may be added to affect other properties of the paper, such as color, printing quality and alkalinity.
[0024] According to the invention, a radio frequency active adhesive is added to the pulp stock, preferably but not necessarily at the same time as the other additives are added. Adding the RF active adhesive to the pulp stock insures that the fibers are completely wetted with the adhesive, since the adhesive is distributed throughout the entire paperboard, not just on the outer surface. Any suitable RF active adhesive can be used, including aqueous based adhesives, since all or most of the water will be removed during the papermaking stage.
[0025] The next step of the invention is to form the pulp stock into a paperboard sheet according to conventional papermaking methods. In brief summary, the pulp stock containing the RF active adhesive is sent to a papermaking machine having a wet end, a press section, and a dryer section. At the wet end, the pulp stock (mainly fiber suspended in water) is deposited onto a loop of porous fabric, or “wire”. Water drains away through the porous fabric as the suspension moves toward the press section, leaving a wet, weak mat of fiber and additives, including the RF active adhesive.
[0026] In the press section, the sheet passes through a series of various sized opposing rollers. As the sheet passes through the pairs of rollers, more water is removed from the sheet. The sheet leaves the press section and enters the dryer section for final water removal. The final paper or paperboard sheet is then wound into rolls for storage and transport. The sheet or web of RF active adhesive impregnated paperboard is then ready to be used to make paperboard structures such as wound paperboard tubes, cores and containers.
[0027] Paperboard frequently is a composite of multiple fiber plies, sometimes referred to as combination board or cylinder board. Often one or more of the plies consists at least partially of waste paper in order to reduce raw material costs.
[0028] As is well known in the art, the manufacture of multiple ply paperboard is accomplished using a cylinder machine. A cylinder is a large hollow rotatable roll covered with wire mesh and partially submerged in a tub or vat of pulp stock. As the wire rotates out of the vat, it carries with it a wet mat of fibers. Water from the mat is drained through the wire mesh and exits out an end of the rotating cylinder. As the fiber mat rotates to the top of the cylinder it is picked up by a horizontal felt pressed against the top of the cylinder by a press roll. The fiber mat is carried to the next cylinder where it is affixed to another ply. A cylinder machine typically consists of no more than eight cylinders.
[0029] In an alternative embodiment of the present invention, the paperboard comprises multiple plies, and the RF active adhesive is added only to the pulp stock used to make the outer ply or plies, thereby minimizing the amount of adhesive required. A cylinder machine may be used for this purpose.
[0030] For illustration purposes, the invention will now be described with respect to the making of a spirally wound container.
[0031] A spirally wound paperboard container would typically have a structural or bodywall layer made of paperboard, a separate polyfoil inner liner, and an outer label, although, for the purposes of the invention, it is not necessary to have a liner or outer label. The paperboard web is advanced toward a shaping mandrel where the web is formed into a cylinder having one or more plies. In conventional practice, prior to winding, the paperboard web is advanced through an adhesive applicator which applies adhesive to at least one side of the web or along at least one marginal edge of the web so that the web adheres to itself as it is wound around the mandrel.
[0032] However, in a departure from conventional practice, the web is not coated with adhesive. Instead, just prior to and/or during winding, the RF active adhesive impregnated web is exposed to RF energy by passing the web between two opposing plates or electrodes, which excites the RF active adhesive within the web, causing the generation of heat sufficient to soften the adhesive within the sheet. As a result, the web becomes tacky and is capable of being adhered to itself or another substrate.
[0033] Next, the web is wound around a stationary mandrel in helical fashion to form a tube, according to conventional practice. The tube is advanced along the mandrel by a conventional winding belt, which is stretched between a pair of opposed pulleys. As described in U.S. Pat. No. 6,296,600, incorporated herein by reference, as the paperboard web is further wrapped around the mandrel and advances back under the mandrel, after one complete revolution, one edge is brought into overlapping contact with the opposing edge of the ensuing portion of the web as the ensuing portion first comes into contact with the mandrel. The opposing edges of the web become abutted together and the still soft adhesive adheres the edges together to form a spirally wound tube which advances along the mandrel.
[0034] As the tube advances along the mandrel the RF active adhesive hardens. The continuous tube is then cut to a desired length at a cutting station and removed from the mandrel.
[0035] Although the invention has been described with respect to the manufacture of a spirally wound cylindrical container, it should be understood that the invention may be used to bond together two or more paperboard sheets to make almost any type of paperboard structure, including convolutely wound tubular containers; structural support posts of the type disclosed in U.S. Pat. Nos. 4,482,054, 5,267,651 and 5,593,039; and non-wound paperboard structures, such as the paperboard side panels that form part of the appliance shipping container disclosed in U.S. Pat. No. 4,811,840.
[0036] Other modifications and alternative embodiments of the invention are contemplated which do not depart from the spirit and scope of the invention as defined by the foregoing teachings and appended claims. It is intended that the claims cover all such modifications that fall within their scope.
|
A method of making a spirally wound dry bonded paperboard structure. The method includes adding a radio frequency active adhesive such as a silicate to the paperboard pulp stock during the paperboard fabrication process to first produce an RF active adhesive impregnated paperboard. The impregnated paperboard is then exposed to an RF energy field prior to or during winding, which activates the adhesive. The invention eliminates the need to apply a water-based adhesive to the paperboard prior to forming the structure, thereby reducing water migration into the paperboard.
| 3
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a surgical instrument, and in particular, to an irrigation/aspiration handpiece.
2. Problems in the Art
Some surgical procedures require simultaneous irrigation and aspiration at the surgical site. One method of accomplishing this would be to operate separate aspiration and irrigation tools at the site. This is especially problematic for small or delicate surgery, for example, in microsurgery.
Combination irrigation/aspiration handpieces have therefore been developed. One useful handpiece is disclosed in U.S. Pat. No. 4,553,957 by inventors Rodger W. Williams and Charles W. Atwood, which is incorporated by reference herein. That patent discloses a handpiece having a hollow interior section used for an irrigation fluid reservoir, and an aspiration cannula extending from an aspiration connection all the way to the end of the surgical tip, through the irrigation fluid reservoir. A second cannula surrounding the aspiration cannula communicates with the fluid reservoir and directs irrigation fluid to the surgical site. A handpiece of this type requires that the irrigation and aspiration cannulas, being of two separate pieces, be secured to one another. Additionally, handpieces of this type are conventional in that irrigation ports from the irrigation cannula are disposed at opposite sides towards the distal end of the irrigation cannula with the position of the aspiration port of the aspiration cannula extending forward of the irrigation ports and being intermediate between the position of the irrigation ports.
There is also a need for a secure and sealing connection so that there is no inter-mixing of the irrigation fluids with the aspiration lines and materials. It is therefore critical that connecting conduits between the irrigation/aspiration sources and the handpiece are secure, reliable, and not subject to deterioration or break down because of strain or loosening.
It is therefore a primary object of the present invention to present an irrigation/aspiration handpiece which improves over or solves the problems and deficiencies in the art.
Another object of the present invention is to provide an irrigation/aspiration handpiece which is accurate, reliable, and simultaneously provides irrigation and aspiration to a surgical site.
A further object of the present invention is to provide an irrigation/aspiration handpiece which does not have exposed, interrupted joints or connecting pieces, and which does not have any edges which are likely to catch or cause tears at the surgical site.
Another object of the present invention is to provide an irrigation/aspiration handpiece which has a surgical tip which has smooth, unitary, uninterrupted surfaces.
A further object of the present invention is to provide an irrigation/aspiration handpiece which has improved irrigation properties without affecting aspiration.
Another object of the present invention is to provide an irrigation/aspiration handpiece which provides minimal strain on conduits between irrigation and aspiration sources and the handpiece.
Another object of the present invention is to provide an irrigation and aspiration handpiece which is efficient, economical, and durable in construction, maintenance and use.
These and other objects, features, and advantages of the present invention will become apparent with reference to the accompanying specification and claims.
SUMMARY OF THE INVENTION
The present invention includes an improved apparatus for irrigating (supplying fluid to) and aspirating (withdrawing fluid from) a surgical site; otherwise called an irrigation/aspiration handpiece. An elongated handle encapsulates separate conduits for irrigation fluid and aspiration. These conduits are connected to irrigation and aspiration sources and enter the proximal end of the handle and proceed through the handle's intermediate body section towards the opposite, distal end of the handle. A nose chamber is positioned in the distal end of the handle, and includes a hollow interior comprising a reservoir for irrigation fluid. The reservoir of the nose chamber is therefore in direct fluid communication with the irrigation fluid conduit.
A surgical tip having a narrow, generally tubular solid housing, is positioned on the distal end of the nose chamber and extends outwardly from the handle. The surgical tip also has a hollow interior section which is itself in direct communication with the reservoir of the nose chamber. Near the distal end of the surgical tip which is tapered and closed, are one or more irrigation outlet openings or ports which are in communication with the hollow interior of the surgical tip. Irrigation fluid therefore communicates from the irrigation conduit through the reservoir of the nose chamber and through the hollow interior of the surgical tip out of the irrigation ports to the exterior of the tip.
The surgical tip also includes an aspiration inlet opening or port between the very distal end of the surgical tip and the aspiration ports. An aspiration cannula extends from the aspiration inlet port through the hollow interior of the surgical tip and through the reservoir of the nose chamber and then is directly put in fluid communication with the aspiration conduit.
The handpiece therefore provides for simultaneous irrigation and aspiration at a surgical site. The surgical tip is unitary, and has uninterrupted surfaces. The edges of the irrigation/ aspiration ports can be rounded to reduce any chance for catching or tearing at the surgical site. The irrigation and aspiration systems are entirely sealed from one another in the handpiece, and the positioning of the aspiration port with respect to the irrigation ports allows sufficient irrigation without obstructing the aspiration capabilities of the handpiece.
In a particular embodiment of the surgical tip, the irrigation ports are radially disposed around the perimeter of the distal end of the surgical tip with the aspiration port being positioned slightly ahead of the irrigation ports on the side of the distal end of the surgical tip. Solid portions of the tip housing separate the irrigation ports. The solid portions are impermeable to fluids. The plurality of irrigation ports provides increased and more beneficial irrigation flow to the surgical site. The irrigation ports can be distributed so that a port-free solid portion of the tip housing between irrigation ports is provided immediately adjacent and proximally to the aspiration port to insure that the irrigation fluid, under pressure, does not disrupt the aspiration capabilities of the handpiece.
Because the aspiration and irrigation conduits extend from outside of the handpiece through the intermediate body section of the handpiece, a strain relief is incorporated into the proximal end of the handpiece. The strain relief consists of an end plug having two apertures to receive both conduits side by side. A strain plug is then positioned interiorally of the end plug and also has two apertures to receive the conduits side by side. However, the two apertures in the strain plug are offset from the apertures in the end plug by rotating the apertures in the strain plug slightly to provide a bending in the aspiration and irrigation conduits. This provides necessary strain relief and assists in securing the conduits in place.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an embodiment of an irrigation/aspiration handpiece according to the present invention.
FIG. 2 is a longitudinal sectional view of the handpiece of FIG. 1.
FIG. 3 is an exploded view of the handpiece of FIG. 1.
FIG. 4 is an enlarged partial sectional view according to FIG. 2.
FIG. 5A is a partial perspective view of the tip of the handpiece of FIG. 1.
FIG. 5B is a distal end view of FIG. 5A.
FIG. 5C is a sectional view taken along lines 5C--5C of FIG. 5B.
FIG. 5D is a top view of FIG. 5A.
FIG. 5E is a sectional view taken along lines 5E--5E of FIG. 5D.
FIG. 6A is a partial perspective view of alternative embodiment of a tip for a handpiece according to the invention.
FIG. 6B is a distal end view of FIG. 6A.
FIG. 6C is a sectional view taken along lines 6C--6C of FIG. 6B.
FIG. 6D is a top view of FIG. 6A.
FIG. 7 is a proximal end view of the handpiece of FIG. 1 with offset strain relief members shown in broken lines.
FIG. 8 is a partial sectional top view taken along lines 8--8 of FIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the drawings, and particularly FIGS. 1-3, there is shown an improved apparatus for irrigating (supplying fluid to) and aspirating (withdrawing fluid from) a surgical site; which for purposes of this description will be referred to as an irrigation/aspiration handpiece 10. The handle 12 of handpiece 10 is an elongated body which in the preferred embodiment has a hollow center bore 14 and an open proximal end 16 and open distal end 18. The terms "distal" and "proximal" relate to the relationship of the opposite ends 18 and 16 of handpiece 10 with the conduits to sources of aspiration and irrigation.
An aspiration conduit 20 enters the proximal end 16 of handle 12 from an aspiration source (not shown), while similarly an irrigation conduit 22 enters the proximal end 16 of handle 12 from an irrigation source (not shown).
A nose chamber 24 is positioned in association with the distal end 18 of handle 12 having its proximal end 26, in the preferred embodiment, sealingly fitted within distal end 18 of handle 12, and having a distal end 28 extending outwardly therefrom. Nose chamber 24 has a hollow interior portion which comprises a reservoir 30 for irrigation fluid. The distal end 28 of nose chamber 24 is open whereas the proximal end 26 contains chamber bulkhead 32, which comprises a first connection 34 to which is attached in fluid communication aspiration conduit 20, and a second connection 36 which is attached in fluid communication to irrigation conduit 22. Second connection 36 is in turn in fluid communication with reservoir 30.
A surgical tip 38 having a narrow, generally tubular solid housing, is secured in association with distal end 28 of nose chamber 24 at its proximal end 40, and extends to its distal end 42 which is tapered and closed. Surgical tip 38 also has hollow interior 44.
An aspiration cannula 46 extends from first connection 34 of chamber bulkhead 32, through reservoir 30 and through hollow interior 44 of surgical tip 38 to near the very distal end 42 of surgical tip 38. Aspiration cannula 46 forms a separate and sealed fluid communication line between aspiration conduit 20 and the distal end 42 of surgical tip 38.
By brief reference to FIGS. 4 and 5A-E, it can be seen that the solid housing of the distal end 42 of surgical tip 38 contains an aspiration port 48 which is in fluid communication with aspiration cannula 46, and also contains a plurality of irrigation ports 50a, b, c, and d, which are in fluid communication with hollow interior 44 of surgical tip 38, which in turn is in fluid communication with reservoir 30 of nose chamber 24, which in turn is in fluid communication with irrigation conduit 22. The irrigation ports 50a, b, c, and d are separated by solid portions 72e, f, g, and h of the solid housing of tip 38. It can therefore be seen that handpiece 10 allows simultaneous irrigation and aspiration at the surgical site.
Also shown in FIGS. 1-4 is a raised indicia member 52 in the form of a fin at the distal end 18 of handle 12, which gives a visual and tactile indicator of the position of the aspiration port 48. For example, in the embodiment of FIG. 1 and 4, aspiration port 48 is positioned on the side of surgical tip 38, whereas raised indicia member 52 is on the top of handpiece 10. With this relationship, a surgeon can always and quickly determine the location of the aspiration port 48.
FIG. 2 shows that aspiration and irrigation conduits 20 and 22 pass through the proximal end 16 of handle 12, and are held in position by end plug 54 and strain plug 56. As can be seen in FIGS. 3 and 7, end plug 54 has two adjacent apertures 58 and 60, whereas strain plug 56 has adjacent apertures 62 and 64 (shown in broken lines in FIG. 7), all of which receive conduits 20 and 22 without constriction to fluid flow therethrough. The apertures 58, 60, 62 and 64, of end and strain plugs 54 and 56 can frictionally restrict and assist in securing conduits 20 and 22.
It can also be seen that in the preferred embodiment, the interior perimeter wall of the hollow center defined by bore 14 is frictionally abutted by a shoulder 66 of chamber bulkhead 32, and that first and second connections 34 and 36 can comprise connecting nipples for tubular aspiration and irrigation conduits 20 and 22. Aspiration cannula 46 can frictionally fit within the first connection 34, whereas the opposite end of irrigation cannula 46 can frictionally fit down into the distal end 42 of surgical tip 38 (see in particular, for example, FIGS. 5C and 6C).
FIGS. 2 and 4 also show that distal end 28 of nose chamber 24 narrows from its proximal end 26. Shoulder 68 is formed interiorly which prevents flange 70 of surgical tip 38 from moving forward when in position. The distal end 42 of surgical tip 38 itself narrows from proximal end 40 to present the narrow, unitary, uninterrupted surface for surgical tip 38 to be inserted into the surgical incision or otherwise used in surgery.
FIG. 3 depicts in exploded view the various parts of the preferred embodiment of the invention shown in FIG. 2, and their relationship to one another.
FIG. 4 shows, by enlargement, clearer detail of the distal portion of instrument 10 as seen in FIG. 2.
FIGS. 5A-E depict in further detail the structure of one preferred embodiment of the distal end of surgical tip 38. FIG. 5A shows in perspective the radially-disposed irrigation ports 50a, b, c, and d, and their relationship to aspiration port 48. It also shows the relationship of Aspiration cannula 46 to the hollow interior 44 of surgical tip 48.
FIG. 5B shows an end or anterior view of distal end 42 of surgical tip 38, and how in the preferred embodiment a port-free solid portion 72h of wider dimensions than solid portions 72e, f, and g, exists between irrigation ports 50a and 50d in alignment with and proximal to aspiration port 48. The reason for wider solid portion 72h is to allow constant irrigation without dislodging or washing away the material immediately forward of and coaxial to aspiration port 48.
In the preferred embodiment of FIGS. 5A-E, wider solid portion 72h consists of a pre-shaped solid area comprising generally a 40° arc segment of the generally conical shape of slanted portion 76. The 40° segment is composed of segments of approximately 20° from either side of a centerline on portion 72h extending to aspiration port 48. Portion 72h generally should be wider than the irrigation ports.
FIG. 5C depicts in greater detail how aspiration cannula 46 can be force fit and secured into narrowed interior portion 74 of surgical tip 38. Aspiration cannula 46 can be of a deformable yet resilient material which allows such securing force fit. Alternative methods of securing aspiration cannula 46 can be used, such as are known in the art. It can be seen that aspiration cannula 46 does not disrupt the flow of irrigation fluid from hollow interior 44 of surgical tip 38 and out of the plurality of irrigation ports 50a-d.
FIG. 5D shows a side view of aspiration port 48 and its relationship to the slanted portion 76 which is intermediate between grounded closed end 78 and narrowed straight portion 80 of surgical tip 38, and the straight sided connection portion 82 of surgical tip 38 which extends back to the proximal end 40 of surgical tip 38.
FIG. 5E shows how in the preferred embodiment, the edges of irrigation ports 50a-d and aspiration port 48 can be rounded to prevent any catching or tearing at the surgical site.
FIGS. 6A-D depict an alternative embodiment for the distal end of the surgical tip. It functions in exactly the same manner as surgical tip 38 in FIGS. 1 through 5, except that it differs in that it has tapered portion 86 which extends from just proximally behind irrigation ports 88a-d, all the way to rounded closed end 90. Thus, for purposes of comparison, the preferred embodiment of FIGS. 5A-E can have slanted portion 76 at an angle of approximately 12° spread from the center longitudinal axis of surgical tip 38, whereas the embodiment of FIGS. 6A-D would have a spread angle of approximately 9° from the longitudinal axis. The embodiment of FIGS. 6A-D thus presents somewhat of a shallower angle.
FIG. 7 shows end plug 54 and strain plug 56 in position in handle 12. It can be seen that apertures 58, 60 of end plug 54 are adjacent and are radially centered from the center of end plug 54. Apertures 62, 64 of strain plug 56 are likewise adjacent and centered from the center of strain plug 56. However, to provide the strain relief, apertures 62, 64 are offset rotationally from apertures 58, 60. In the preferred embodiment, this offset is approximately 30°.
FIG. 8 shows how the offset creates a bend 92 in aspiration conduit 20 which assists in securing conduit 20 in place and also provides strain relief. The same effect is caused on irrigation conduit 22.
Thus, the present invention provides reliable and segregated, but simultaneous irrigation and aspiration. It is also important to note that handpiece 10 also provides an irrigation fluid reservoir, which facilitates consistent and constant irrigation, with the plurality of radially spaced irrigation ports providing further advantageous irrigation, which is more complete and less turbulent than prior aspiration irrigation handpieces which generally utilize two irrigation ports on opposite sides of the irrigation cannula.
The different embodiments of the surgical tips highlight the advantage of the present invention in that the entire surgical tip has no interruptions, junctions, joints, or protrusions, and that all surfaces are gradually slanted or rounded. The surgical tip is essentially unitary, which is advantageous for clean wound penetration. Conventional instruments are fabricated by coaxially aligning two cannulas which, of necessity, requires a joint or junction or some interruption in the surface. Even the smallest interruption can cause tearing or tissue damage.
It will be appreciated that the present invention can take many forms and embodiments. The true essence and spirit of this invention are defined in the appended claims, and it is not intended that the embodiment of the invention presented herein should limit the scope thereof.
|
A hand-held cannula assembly for irrigating and aspirating opthalmic surgical sites includes as irrigation cannula circumscribed about an aspiration cannula and extending out through the forward end of the assembly from a reservoir for the irrigation fluid in the handle. Pressurized irrigation fluid is supplied to the reservoir through the rearward end of the handle and flows through openings in the irrigation cannula periphery into an annular flow passage between the two cannulas. An opening in the irrigation cannula issues the irrigation fluid at the surgical site. Aspiration fluid is drawn into the aspiration cannula which extends through the handle interior to an outflow opening at the rearward handle end. The irrigation/aspiration tip exterior is made to be smooth, protrusionless, unitary and one-piece in design to afford a minimum in tissue tearing at the surgical site, while also allowing improved irrigation fluid flow a the site.
| 0
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to digital imaging devices and methods, and more particularly to multimode scanning of an image sensor.
2. Description of the Related Art
Imaging sensors are used in digital cameras and camcorders, high definition televisions (HDTV), telescopes and other equipment. Two types of image sensors commonly used for these applications are charge coupled device (CCD) and complementary metal oxide semiconductor (CMOS). Each includes a detector portion, typically a two-dimensional array of pixel circuits. Each pixel circuit contains both a detector that converts photons (electromagnetic radiation) into a charge (electron-hole pairs), that accumulates at the detector, and an output circuit. Each detector has a maximum charge that it is capable of holding. When this maximum charge has accumulated, the detector saturates and cannot hold any more.
Each pixel senses one small area within the larger image, with its circuit outputting a signal representing that portion of the image. The pixel circuits may require resetting to obtain a new image or to accommodate a bright star that has saturated the circuit.
Image sensing for astronomy applications currently requires two image sensors to record an image of the sky. One sensor is used to fix the telescope orientation with respect to a “guide star” as the earth rotates, and another to sense the image. The guide star is typically a bright star that can be easily tracked. Because a bright star is used, the guide star sensor quickly saturates and must be reset more frequently than the image sensor. Also, for accurate tracking, a high frame rate is required for the guide star sensor.
Most imaging sensors read out and reset rows or columns of pixels at a time. This makes it difficult to concentrate on only one portion of the overall image.
SUMMARY OF THE INVENTION
The present invention is a method and system which overcomes the problems noted above. It provides for multiple scanning modes in an image sensor. Selected subarrays of an image sensor can be read and reset independently of the rest of the sensor. This is useful for the astronomy application mentioned above, as well as in other applications for which only a portion of an image sensor needs to be read and/or reset.
One embodiment of the invention includes a controller configured to produce a control signal that indicates a subarray to be scanned, selection circuits connected to select the subarray, and scanning circuits connected to scan the selected subarray.
Further features and advantages of the invention will be apparent to those skilled in the art from the following detailed description, taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a digital imaging system utilizing multiple mode control according to one embodiment of the invention.
FIG. 2 is a schematic diagram of an individual pixel reset circuit used in one embodiment of the invention.
FIG. 3 is a schematic diagram of one implementation for the digital imaging system of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
An imaging system according to one embodiment of the invention is shown in FIG. 1 . It includes a multiple mode control circuit 12 that is configured to scan an array of electromagnetic radiation sensors 14 and selectable subarrays 16 . The invention is most commonly applicable to photosensitive detectors which are sensitive to visible light, infrared and/or ultraviolet, but it is also applicable to other regions of the electromagnetic spectrum.
Control circuit 12 includes a controller 18 that controls the operation of the imaging system. Controller 18 sends control signals on control lines 20 and 20 a to selection circuits 22 and 22 a , respectively. The control signals include the coordinates of a subarray to be scanned. Selection circuits 22 and 22 a generate selection signals on selection lines 24 and 24 a that determine the subarray to be scanned, and whether to read or reset the subarray.
Scanning circuits 26 and 26 a include read circuits 28 and 28 a and reset circuits 30 and 30 a , respectively. Scanning circuits 26 and 26 a activate the read or reset circuits to either read or reset a desired sensor in array 14 . When activated, read circuits 28 and 28 a generate read signals on lines 32 and 32 a that cause a selected sensor in the array or subarray to be read out. Reset circuits 30 and 30 a , when activated, generate reset signals on lines 34 and 34 a that cause a reset of a selected sensor in the array or subarray.
Scanning is typically accomplished by reading out the voltage on an individual sensor, then resetting it. However, a scan could be a read without a reset, or a reset without a read. With the present configuration, entire rows or columns can be read or reset at one time, or selected sensors in the row or column can be read or reset.
The sensors in array 14 are defined and accessed by a set of coordinates. While the description above is for rows and columns, these could be interchanged, or other array geometries such as concentric circular, staggered pixels, or three-dimensional could be used.
Controller 18 controls whether the entire array 14 or a subarray 16 is scanned. Subarrays can be read and reset independent of the entire array. The controller can pause the scanning of the full array at any time to scan a subarray. This is particularly useful when a portion of the full array becomes saturated. More than one subarray may be scanned if desired.
One possible pixel with an individual reset circuit is shown in FIG. 2 . The pixel includes an electromagnetic radiation sensor 42 that accumulates charge in response to received radiation, and a reset transistor 44 that, when activated by a logic gate 46 , connects a reset voltage on reset voltage line 48 to sensor 42 to reset its voltage level. A voltage source 50 supplies reset voltage line 48 , and can provide enough current to reduce the voltage on the sensor to the level on reset voltage line 48 . The reset voltage is typically a low voltage such as 0-500 millivolts for a p-n type sensor. Sensor 42 is typically a photodiode, but may be a phototransistor or other type of electromagnetic sensing device.
A read transistor 52 and a source follower transistor 54 have their source-drain circuits connected in series from a read bus 56 to the source-drain circuit of reset transistor 44 . Source follower transistor 54 has its gate connected to the detector's output node 58 . The voltage at node 60 , between transistors 52 and 54 , tracks the voltage at detector node 58 through the normal source follower action of transistor 54 . To read out a signal from the pixel, a voltage is applied to a read enable line 62 , which is connected to the gate of read transistor 52 , sufficient to turn on the read transistor, which then applies the voltage at node 60 to the read bus 56 through its activated source-drain circuit.
Logic gate 46 receives logic inputs from row and column reset lines 64 and 66 . When both row reset line 64 and column reset line 66 are activated, gate 46 activates reset transistor 44 . This causes the voltage on detector node 58 to be set to the voltage on reset voltage line 48 , as described above.
Logic gate 46 is typically an AND gate, but other types of logic gates that turn on reset transistor 44 when row reset line 64 and column reset line 66 are activated could be used. The reset lines can be activated by positive, zero or negative voltages, depending upon the nature of the logic gate 46 . For example, if an exclusive NOR gate is employed, reset transistor 44 would be turned on in response to an absence of voltage on both reset lines. The type of logic gate used and the nature of the signals applied to the reset lines also depend on the nature of reset transistor 44 . For example, if transistor 44 were an nFET device rather than a pFET, gate 46 would need to provide an opposite signal in response to the same inputs from the reset lines. As an alternative to logic gate 46 , a second reset transistor could be connected in series with transistor 44 , with one transistor controlled by the row reset line 64 and the other by column reset line 66 , so that reset occurs only when both transistors are activated.
A simplified digital imaging system with an array of pixels 14 employing multiple mode control according to one embodiment of the invention is shown in FIG. 3 . Individual pixels 15 are shown spaced widely apart for ease of illustrating the various signal lines, but in practice they would be much closer together.
Selection circuit 22 includes a full-array shift register 70 that is controlled by the controller 18 (not shown). When full array select circuit 72 is activated, it sends a signal to AND gate 74 , which advances the full-array shift register 70 each time a pulse is received from a column clock 76 . This shifts all values in the shift register to the right by one place. Controller 18 applies a logic “1” to first register from the left within full array shift register 70 . With successive clock pulses, the 1 is shifted through the register to enable a desired operation upon each column in the array in succession. The corresponding row circuitry operates in a similar fashion, except its timing is controlled by a row clock 77 that operates at a frequency that is less than that of the column clock by a factor equal to the number of columns. This allows the pixels in the first row to be operated upon in sequence at each column clock pulse. A row clock pulse is generated when the last pixel in the first row has been operated upon. Each pixel in the second row is then operated upon in sequence at each successive column clock pulse, and so on until the entire array has been scanned.
When full-array select circuit 72 is deactivated by the controller, its logic 0 output is inverted to a logic 1 by an inverter 75 and applied as one input to another AND gate 78 . The other input to AND gate 78 is supplied by the column clock 76 . AND gate 78 controls a subarray shift register 80 that operates in a manner similar to full-array shift register 70 . The full-array select circuit 72 thus controls whether scanning is performed by the full-array shift register 70 or the subarray shift register 80 .
Subarray shift register 80 receives location information, including a start and stop column for the subarray to be scanned, from a subarray start address decoder 82 and a subarray stop address decoder 84 , respectively. The decoder 82 and 84 are programmed with this information by controller 18 . Output lines are provided from the decoders to each individual register within subarray shift register 80 . Start address decoder 82 activates one output line at a time, corresponding to the column number received from the controller. For example, if the controller provided the digital number 8, the decoder would place a “1” into the eighth bit from the left in the shift register 80 , causing subarray scanning to start at the eighth column from the left. The first decoder output line is activated in response to a digital zero input from the controller. A decoder with an n bit input can control 2 n outputs, allowing 2048 lines of rows and/or columns can be controlled with an 11-bit word from the controller. Other decoder configurations can be used for different size arrays.
In this manner, a “1” is placed into the shift register 80 at the column where the subarray is to start. The “1” is shifted through the shift register to sequentially scan the pixels of a given row within the subarray.
When the stop column for the subarray is reached, a 0 is forced into the register following the stop column location by the stop address decoder 84 to discontinue scanning. Alternatively, another logic gate (not shown) may be used between the decoders and the shift registers. When activated, the logic gate would place a “0” into the register following the last row or column of the subarray to be scanned. With this configuration, the start and stop columns may be placed into the subarray shift register and the subarray scanned. Corresponding row circuitry similarly controls the start and stop rows of the subarray to be scanned.
The array 14 is typically read from the upper left corner to the lower right corner, row by row. There is one register in full-array shift register 70 per column. When a register has a “1” in it, a signal is sent to a multiplexer 86 for that column. An activated full-array select circuit 72 activates full-array shift register 70 at each clock pulse, and multiplexer 86 passes the signal from full-array shift register 70 . A deactivated full-array select circuit 72 activates subarray shift register 80 at each clock pulse, and multiplexer 86 passes the signal from subarray shift register 80 .
Multiplexers 86 provide one of two signals needed to activate either a read logic gate 88 or a reset logic gate 90 for a particular column. The other input to activate read logic gate 88 comes from a read enable circuit 92 , which is controlled by the controller. The other input to activate reset logic gate 90 comes from a reset enable circuit 94 , which is also controlled by the controller.
The reset of an individual pixel 15 occurs in response to activation of reset logic gate 90 , which activates column reset line 66 and provides one input to logic gate 46 , as described in connection with FIG. 2 . The other input needed to reset a pixel is provided from row reset line 64 , which is activated in a manner similar to column reset line 66 , by corresponding circuitry for each row of array 14 .
The reading of pixels occurs when the read enable line 62 is activated by corresponding row circuitry, which matches and sends the voltage from every sensor in a selected row to the read bus for that row, as described above. Read logic gate 88 is then enabled, sending a signal that activates a vertical read enable transistor 96 that allows the voltage on read bus 56 for a selected column to be read out by the controller. When read enable line 62 is activated, the voltage from every sensor in the row is applied to its respective read bus 56 . However, the only voltages read out from the read buses are from the column(s) that have their vertical read enable transistor 96 activated. In this manner, an entire row or individual sensors can be read out.
The row selection circuit 22 a is similar to the column selection circuit 22 . Row selection circuit 22 a includes subarray start and stop decoders 82 a and 84 a , a subarray shift register 80 a , a full-array shift register 70 a , a multiplexer 86 a , full-array select circuit 72 a , read enable circuit 92 a , reset enable circuit 94 a , and logic gates 74 a and 78 a , all of which are connected and operate in a manner similar to the corresponding column elements.
The row selection circuit 22 a controls logic gates 90 a and 88 a , which in turn control row enable and reset lines 62 and 64 each row. Activated row and column reset lines 64 and 66 reset the pixel at their intersection, as described above. An activated read enable line 62 allows the voltage from each sensor in that row to be read by read bus 56 and applied to a common read bus 95 when a corresponding vertical read enable transistor 96 is activated. Row selection circuit 22 a also includes horizontal clock 77 that is controlled as described above. A keep-alive current source 98 can be connected to the common read bus to maintain the source follower transistors in the read out pixels in an active state, or less desirably an individual keep-alive transistor could be provided within each pixel.
With this configuration, the full array and a subarray (or more than one subarray) can be scanned in any desired order. For example, the scanning of the full array can be interrupted to scan a subarray, or the subarray can be scanned before or after the full array is scanned. When reactivated, the full-array scanning continues at the point of interruption, because full-array shift registers 70 and 70 a retain the values of the row and column at which scanning was interrupted.
While particular embodiments of the invention have been shown and described, numerous variations and alternate embodiments will occur to those skilled in the art. For example, while FETs have been shown, other transistor types such as bipolar could be used. Accordingly, it is intended that the invention be limited only in terms of the appended claims.
|
Multiple scanning modes are provided for an array of electromagnetic radiation sensors. In the preferred implementation both selectable subarrays and the overall array can be read out and reset in any desired order, including interrupting a full array scan for a subarray scan and then resuming the full array scan.
| 7
|
CROSS REFERENCE TO THE RELATED APPLICATIONS
The present application is a continuation-in-part of U.S. patent application Ser. No. 08/213,790, filed on Mar. 16, 1994, entitled "SHIFT CONTROL SYSTEM OF AUTOMATIC TRANSMISSION" which is assigned by the same assignee as the present application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a control system of an automatic transmission and, in particular, to a control system of the type having a torque converter, a lock-up clutch for transmitting an engine output to a shift gear mechanism and an adjusting valve disposed in an engaging passage of a frictional element for controlling an engaging pressure of the element.
2. Description of Related Art
In an automatic transmission where a torque converter is combined with a shift gear mechanism so as to selectively operate frictional elements, such as clutch of the shift gear mechanism to switch a power transmitting passage of the shift gear mechanism and thus to switch a shift stage automatically in accordance with a vehicle driving condition, it has been known that in order to reduce an energy loss through the torque converter and to improve a fuel consumption efficiency, a lock-up clutch is provided for directly connecting input and output members of the torque converter under a predetermined driving condition where there is no need to amplify the engine torque transmitted therethrough and the like. In this case, as disclosed in Japanese Patent Public Disclosure No. 4-140569, laid open to the public in 1992, there is provided a pressure regulator for adjusting a pressure difference between an engaging chamber introducing engaging pressure of the lock-up clutch and a releasing chamber introducing a releasing pressure thereof. The control pressure of the pressure regulator is changed in accordance with a pressure control valve such as a solenoid valve so that a half engaged condition or slip condition of the lock-up clutch can be controllably established.
Meanwhile, it has also been known that the engaging pressure for the frictional elements is controlled by the pressure regulator. For example, in Japanese patent Public Disclosure No. 1-150055, laid open to the public in 1989, it is disclosed that a pressure regulator is disposed in a hydraulic passage for engaging a frictional element and that a control pressure introduced to the pressure regulator is controlled by a pressure control solenoid valve. According to the disclosure in the Japanese Patent Public Disclosure No. 1-150055, it is possible to widely control the engaging pressure to the frictional element. As a result, this structure enables an engaging and releasing action of the frictional element to be made smoothly to thereby reduce a shift shock. In addition, after the shift operation, the capacity of the torque transmitting of the frictional element is adapted to the input torque thereto so that a driving loss of oil pump can be reduced and the engine torque can be transmitted safely.
It should, however, be noted that if such a pressure control valve which solely serves for the pressure control of each of the frictional element is employed to control the control pressure for the pressure regulator as disclosed in the above Japanese publication, the number of parts is undesirably increased.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to properly control an engaging pressure of a frictional element utilizing a pressure control solenoid valve for a lock-up clutch of an automatic transmission.
It is another object of the present invention to control the engaging pressure of a frictional element by means of a pressure regulator without providing a pressure control solenoid valve which solely serves for the pressure control of the frictional element.
It is a further object of the present invention to properly control an engaging pressure of a frictional element without increasing the number of parts.
The above and other objects of the invention can be accomplished by a control system of an automatic transmission comprising a torque converter, a lock-up clutch for directly connecting input and output members of the torque converter, a pressure control solenoid valve which controls an engaging pressure of the lock-up clutch, a pressure regulator disposed in an engaging passage of a frictional element for adjusting a primary pressure to produce an output hydraulic pressure regulated in accordance with a control pressure introduced into a control port of the pressure regulator and a control pressure supply device for introducing a hydraulic pressure controlled by the pressure control solenoid valve into the control port.
In another aspect of the invention, a control device for an automatic transmission further comprises a switching valve to which the hydraulic pressure controlled by the pressure control valve is introduced as a control pressure. The switching valve is actuated to introduce an interrupt pressure to an interrupt port of the pressure regulator so as to prevent the pressure regulator from reducing the output pressure in the course of the pressure regulating action when the control pressure introduced to the control port is greater than a predetermined value.
In a further aspect of the invention, a control system of an automatic transmission further comprises a pressure control interrupt device for preventing the pressure regulator from reducing the output pressure in the course of the pressure control action when an engaging force of the lock-up clutch is controllable.
According to the present invention, a hydraulic pressure controlled by the pressure control solenoid valve which controls the engaging force of the lock-up clutch of the torque converter is introduced to the control port of the pressure regulator disposed on an engaging pressure introduction passage for a frictional element. As a result, the engaging pressure introduced to the frictional element during a shift operation can be effectively controlled by means of the pressure regulator without employing a pressure control solenoid valve which solely serves for the control of the engaging pressure of the frictional element. Accordingly, it is possible to effectively control both the engaging force of the lock-up clutch and the engaging force of the frictional element during the shift operation.
In particular, according to the above one aspect of the invention, there is provided a switching valve to which a hydraulic pressure adjusted by the pressure control solenoid valve is introduced. The switching valve supplies an interrupt pressure to an interrupt port for preventing the pressure regulator from reducing output pressure thereof during the pressure adjusting action of the frictional element. As a result, the control range of the engaging pressure of the frictional element can be reduced so that a sophisticated control of the engaging pressure can be accomplished during a shift operation due to the change of the driving condition. In addition, after the shift operation, the frictional element is kept engaged reliably.
In another aspect of the present invention, a pressure control interrupt device which prevents the pressure regulator from controlling, for example, reducing the output pressure through the engaging force control action in the case where the engaging force of the lock-up clutch is controllable, the frictional element is kept engaged reliably even if the lock-up clutch is actuated to make a slip control with the frictional element being engaged.
Further objects, features and advantages of the present invention will become apparent from the Detailed Description of Preferred Embodiments which follows when read in light of the accompanying Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of an automatic transmission used with a shift control system in accordance with a preferred embodiment of the present invention;
FIG. 2 shows a hydraulic control circuit incorporated into the automatic transmission of FIG. 1;
FIG. 3 is a block chart of a control system for the automatic transmission;
FIG. 4 is an enlarged view of the hydraulic control circuit showing a condition during the 2-3 shift operation;
FIG. 5 is a similar view to FIG. 4 showing the 2-3 shift operation;
FIG. 6 is a time chart showing a relationship between a 3-4 clutch pressure and a duty control pressure of the first duty solenoid valve;
FIG. 7 is an enlarged view of the hydraulic control circuit showing a condition during the slip control condition of the lock-up clutch.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, an automatic transmission 10 according to the present invention includes a torque converter 20, a transmission gear mechanism 30 driven by an output of the torque converter 20, a plurality of frictional elements 41-46, such as clutches and brakes for switching a power transmitting path of the transmission gear mechanism 30 and one way clutches 51 and 52 among running ranges D, S, L and R and shift stages 1-4 in the D range, 1-3 in the S range and 1 and 2 in the L range.
The torque converter 20 is provided with a pump 22 integral with a transmission case 21 connected with an output 20 shaft 1 of an engine, a turbine 23 disposed facing the pump 22 and driven thereby through a hydraulic fluid, a stator 25 disposed between the pump 22 and turbine 23 and carried by the converter case 21 through a one way clutch 24 and a lock-up clutch 17 for directly connecting the output shaft 16 with the engine output shaft 2 through the converter case 11. A rotation of the turbine 23 is transmitted to the transmission gear mechanism 30 through a turbine shaft 27. To the engine output shaft 1 is connected a pump shaft 12, which passes through the turbine shaft 27, drives an oil pump 13 which is disposed at a rear end portion of the transmission gear mechanism 30.
The transmission gear mechanism 30 is constituted by Ravigneaux-type planetary gear mechanism and provided with a a small sun gear 31 arranged over the turbine shaft 27, a large sun gear 32 arranged over the turbine shaft 27 rearward of the small sun gear 31, a plurality of short pinion gears 33 meshed with the small sun gear 31, long pinion gear 34 of which rear portion is meshed with the large sun gear 32, a carrier 35 rotatably supporting the long pinion gear 34 and the short pinion gear 33 and a ring gear 36 meshed with the long pinion gear 34.
Between the turbine shaft 27 and small sun gear 31 are disposed a forward clutch 41 and a first one way clutch 51 in tandem. A coast clutch 42 is juxtaposed with the clutch 41 and 51. A 3-4 clutch 43 is disposed between the turbine shaft 27 and the carrier 35. A reverse clutch 44 is disposed between the turbine shaft 27 and the large sun gear 32. Between the large sun gear 32 and the reverse clutch 44 is disposed a 2-4 brake 45 of a band brake for fixing the large sun gear 32. A second one way clutch 52 receives a reaction force of the carrier 35 and a low-reverse brake 46 fixes the carrier 35. The ring gear 36 is connected with the output gear 14 through which the rotation is transmitted to right and left wheels (not shown).
Explaining a relationship between the operations of the clutches 51 and 52 and the shift stages, in the first stage, the forward clutch 41 is engaged and the first and second one way clutches 51 and 52 are locked. As a result, the output rotation of the torque converter 20 is transmitted to the small sun gear 31 of the transmission gear mechanism through the turbine shaft 27, forward clutch 41 and one way clutch 51. In this case, the carrier 35 is fixed by means of the second one way clutch 52 so that the transmission gear mechanism 30 operates as a fixed gear train which transmits the rotation from the small sun gear 31 to the ring gear through the short pinion gear 33 and long pinion gear 34 without making a differential action. As a result, the first stage of a large reduction ratio corresponding to a diameter ratio between the small sun gear 31 and the ring gear 36 is obtained.
In a second stage, the 2-4 brake 45 is further engaged in addition to the condition of the first stage. The large sun gear 32 is fixed and the second one way clutch 52 is brought to a racing condition. As a result, the rotation of the turbine shaft 27 is transmitted to the small sun gear 31 and then to the long pinion gear 34 through the short pinion gear 33. In this case, since the large sun gear 32 is fixed, the long pinion gear 34 moves around the large sun gear 32 and thus the carrier 35 is rotated. As a result, the rotation speed of the ring gear 36 is increased by the rotation of the carrier 35 (revolution speed of the long pinion gear 34) compared with the first stage. Thus, the second stage of a smaller reduction ratio than the first stage is obtained. In this case, the 2-4 brake 45 is operated to apply the braking force against normal rotation or rotation for a forward movement.
In a third stage, the 2-4 brake is released in the second stage and the 3-4 clutch 43 is engaged. As a result, the rotation of the turbine shaft 27 is transmitted to the small sun gear 31 through the forward clutch 41 and first one way clutch 51 as well as to the carrier 35 through the 3-4 clutch 43. Thus, the transmission mechanism 30 is integrally rotated so that the third stage is obtained in which the ring gear 36 is rotated at the same speed as the turbine shaft 27.
In a fourth stage, the 2-4 brake which is once released in the third stage is engaged again. Therefore, the rotation of the turbine shaft 27 is transmitted to the carrier 35 of the transmission gear mechanism 30 through the 3-4 clutch 43 so that the long pinion gear 34 moves around the sun gear 32. In this case, since the large sun gear 32 meshed with the long pinion gear 34 is fixed by means of the 2-4 brake 45, the long pinion gear 34 moves around the sun gear 32 together with the carrier 35 and revolves on it own axis. As a result, the rotation of the ring gear 36 meshed with the long pinion gear 34 is increased by the rotation of the carrier 35 (the rotation of the turbine shaft 27) and the rotation of the long pinion gear 34 on its own axis so that the fourth stage of an over drive can be obtained. In this case, the forward clutch is engaged. It should be noted that the one way clutch 51 in tandem with the forward clutch 41 is raced so that there is no fear that the rotation of the turbine shaft 27 is introduced to the small sun gear 31.
In a rearward stage, the reverse clutch 44 and the low-reverse brake 46 are engaged. Thus, the rotation of the turbine shaft 27 is introduced to the large sun gear 32 and the carrier 35 of the transmission gear mechanism 30 is fixed. Therefore, the rotation of the turbine shaft 27 is transmitted to the ring gear 36 through a fixed gear train including the large sun gear 32 and long pinion gear 34. A reduction ratio corresponding to the diameter of large sun gear 34 and ring gear 36 can be obtained. In this case, the rotating direction of the ring gear 36 is opposite to that of the turbine shaft 27 or the large sun gear 32.
The first one way clutch 51 transmitting the rotation in the first to third stage and the second one way clutch 52 bearing a reaction force in the first stage are raced in a coasting condition. Therefore, in the above shift stages, the engine brake is not enacted. However, in the third stage in D range, second and third stages of S range and first and second stages of L range, the coast clutch 42 in parallel with the first one way clutch 51 is engaged and in the first stage of L range, low-reverse brake 46 in parallel with the second one way clutch 52 is engaged to provide the engine brake.
Table 1 shows operations of the respective frictional elements 41-46 such as clutches and brakes and one way clutches 51 and 52.
TABLE 1__________________________________________________________________________ LOW ONEWAYFORWARD COAST 3-4 REVERSE 2-4 REVERSE CLUTCHCLUTCH CLUTCH CLUTCH CLUTCH BRAKE BRAKE FIRST SECONDRANGE(41) (42) (43) (44) (45) (46) (51) (52)__________________________________________________________________________R ◯ ◯ND 1 ◯ ◯ ◯ 2 ◯ ◯ ◯ 3 ◯ ◯ ◯ ◯ 4 ◯ ◯ ◯S 1 ◯ ◯ ◯ 2 ◯ ◯ ◯ ◯ 3 ◯ ◯ ◯ ◯L 1 ◯ ◯ ◯ ◯ ◯ 2 ◯ ◯ ◯ ◯__________________________________________________________________________
Next, a hydraulic pressure control circuit controlling actuators of the frictional elements 41-46 is explained hereinafter. The automatic transmission 10 is provided with a hydraulic control circuit 60 as shown in FIG. 2.
An actuator 45a of the 2-4 brake 45 of band brake includes a servo piston provided with an apply port 45b and release port 45c. When the hydraulic pressure is applied to only the apply port 45b, the actuator 45a engages the 2-4 brake 45. On the other hand, when no hydraulic pressure is applied to the ports 45b nor 45c or hydraulic pressure is applied both the ports 456b and 45c, the 2-4 brake is released. Actuators of the other frictional elements 41-44 and 46 are constituted by conventional hydraulic pistons respectively to engage the frictional elements 41-44 and 46.
The hydraulic control circuit 60 includes a regulator valve 61 for adjusting a hydraulic pressure delivered to a main line 110 from the oil pump 13 of FIG. 1 to a predetermined line pressure, a manual valve 62 for selecting a range by a manual operation, a first, second and third shift valve 63, 64 and 65 for controlling the hydraulic pressure of the actuators of the frictional elements 41-46.
The manual valve 62 is able to select one of D, S, L ranges for forward movement, R range for rearward movement, N range for neutral position and P range for parking. In the ranges of the forward movement, the manual valve 62 connects the main line 110 with a forward line 111 and with a rearward line 112 in the R range.
The first, second and third shift valves 63, 64 and 65 are formed with control ports 63a, 64a and 65a. To the ports 63a and 64a are connected first and second base pressure lines 113 and 114 separated from the forward line 111 respectively. To the control port 65a of the third shift valve 65 is connected a third base pressure line 115 separated from the main line 110. On the base pressure lines 113, 114 and 115 are disposed a first, second and third solenoid valves 66, 67 and 68 respectively. When the first and second solenoid valves 66 and 67 are ON, the valves 66 and 67 discharge the control pressures from the control ports 63a and 64a to move spools of the first and second shift valves 63 and 64 at left positions respectively. When OFF, the solenoid valves 66 and 67 move the spools of the valves 63 and 64 against a resilient force of a spring to the right positions. The third solenoid valve 68 discharge the control pressure of the control port 65a to move the spool of the valve 65 to a right position when it is ON. When OFF, the valve 68 introduce the control pressure to the port 65a from the third base pressure line 115 to move the spool against a resilient force of spring to a left position.
The solenoid valves 66-68 are ON, OFF controlled based on signals from a controller on a predetermined map set in accordance with a vehicle speed and a throttle opening of the engine. Consequently, the positions of the spools of the shift valves 63-65 are switched to thus switch hydraulic paths of the frictional elements 41-46 so that the elements 41-46 are engaged as shown in Table 1. Relationships between ON, OFF operations of the solenoid valves 66-68 and respective shift stages of the D, S and L ranges are shown in Table 2.
TABLE 2__________________________________________________________________________RANGE D S LSHIFT STAGE 1 2 3 4 1 2 3 1 2__________________________________________________________________________FIRST OFF ON ON ON OFF ON ON OFF ONSOLENOIDVALVE (66)SECOND ON ON OFF OFF ON ON OFF ON ONSOLENOIDVALVE (67)THIRD ON ON OFF ON ON OFF OFF OFF OFFSOLENOIDVALVE (68)__________________________________________________________________________
When the D, S or L are set by the manual valve, a line 116 is separated from the forward line 111 connected with the main line 110. The line 116 as a forward clutch line is connected to a forward clutch 41 through an orifice 69 and one way orifice 70. Thus, the forward clutch 41 is usually engaged in the D, S and L ranges. On the forward clutch line 116 is disposed N-D accumulator 71 downstream of the one way orifice 70 through line 117.
The forward line 111 is connected with the first shift valve 63 and is communicated with a servo apply line 118 and with the apply port 45b of the servo piston 45a when the first solenoid valve 66 is turned on so that the spool of the shift valve 63 is shifted to the left position. Thus, when the first solenoid valve 66 is ON in the D, S, L ranges, in other words, when the second, third and fourth shift stages in the D range, second and third shift stage in the S range and the second shift stage in the L range are established and where the hydraulic pressure (servo apply pressure) is introduced into the apply port 45b and a hydraulic pressure (servo release pressure) is not introduced into the release port 45c, the 2-4 brake is engaged. A 1-2 accumulator 74 is connected with the apply port 45b through a line 119 and an accumulation cut valve 73.
The forward line is also connected to the third shift valve 65 and is communicated with a coast clutch line 120 when the spool of the shift valve 65 is in the left position. The coast clutch line 120 is connected to the coast clutch 42 through a coast control valve 75 and one way orifice 76. Thus, when the third solenoid valve 68 is OFF in the D, S and L ranges, in other words, when the third shift stage in the D and S ranges, and the second shift stage in the S and L ranges, and the first shift stage in the L range are established, the coast clutch 42 is engaged.
Further, the forward line 111 is connected to the second shift valve 64 and is communicated with a 3-4 clutch line 121 when the second solenoid valve 67 is OFF and thus the spool of the second shift valve 64 is located at the right position. The line 121 is further connected to a 3-4 clutch 43 through a 3-4 control valve 77. Thus, when the second solenoid valve 67 is OFF in the D, S and L ranges, or when the third and fourth stages of D range and third shift stage of the S range are established, the 3-4 clutch is engaged.
A line 122 separated from the line 121 is connected to the shift valve 65 and is communicated with a servo release line 123 which is connected with the release port 45c of the servo piston 45a when the third solenoid valve 68 is OFF so that the spool of the shift valve 65 is in the left position. As a result, the servo release pressure is introduced to the release port 45c of the servo piston 45a so that the 2-4 brake 45 is released when the second and third solenoid valves 67 and 68 are OFF, in other words, when the third shift stages in the D and S ranges are established.
A line 124 separated from the forward line 111 is connected with the first shift valve 63. The line 124 is connected to a line 125 which is connected to the second shift valve 64 when the spool of the first shift valve 63 is in the right position. On the other hand, to the second shift valve 64 is connected a line 126 which is connected to the line 125 when the second solenoid valve 67 is ON to shift the spool of the second solenoid valve 67 at the left position. The line 126 is connected to the third shift valve 68 through a ball valve 78 and a line 127. The line 126 is connected to a low reverse brake line 128 which is connected to a low reverse brake 46 through a low reducing valve 79 when the third solenoid valve 68 is OFF to shift the spool of the third shift valve 65 at the left position. Thus, the low reverse brake 46 is engaged when the first, second and third solenoid valves 66-68 are OFF, ON and OFF respectively, or when the first shift stage of the L range is established.
A line 129 separated from the reverse line 112 which is connected to the main line 110 in the R range is connected to the third shift valve 65 through an orifice 80, one way orifice 81, the ball valve 78 and the line 127, and is communicated with the reverse brake line 128 when the third solenoid valve 68 is OFF to shift the spool of the valve 65 at the left position. The line 112 as a reverse clutch line 130 is also connected with the reverse clutch 44 through a one way valve 82 which interrupts a discharging flow of the hydraulic fluid. Thus, in the R range, the low reverse brake 46 is engaged when the third solenoid valve 68 is OFF. On the other hand, the reverse clutch is normally engaged in the R range. Meanwhile, N-R accumulator 83 is connected to a line 131 which is separated from the line 129 between the one way orifice and the ball valve 78.
The hydraulic control valve 60 is provided with a fourth shift valve 84 and lock-up control valve 85 for controlling the lock-up clutch 26 of the torque converter 20. To the fourth shift valve 84 and lock-up control valve 85 is connected a converter line 132 which is connected to the regulator valve 61 through the converter relief valve 86. To a control port 84a at one end of the fourth shift valve 84 is connected a base control pressure line 134 which is connected to the main line 110 through a line 133. The converter line 132 is brought into communication with a releasing line 135 which is connected with a releasing chamber 26a of the torque converter 20 to release the lock-up clutch 26 when a fourth solenoid valve 87 connected to the port 84a for making a lock-up control is OFF to shift the spool of the shift valve 84 at the left position. As a result, the lock-up clutch is released to establish the converter condition.
When the fourth solenoid valve 87 is turned ON to discharge the control pressure from the port 84a to thereby shift the spool of the valve 84 at the right position, the converter line 132 is brought into communication with an engaging line 136 which is connected to an engaging chamber 26b of the torque converter 20 so that the lock-up clutch is engaged. Concurrently, the line 135 is brought into communication with the lock-up control valve 85 through the shift valve 84 and an intermediate line 137 so that a hydraulic pressure adjusted in the control valve 85 is introduced to the releasing chamber 26a as a releasing pressure of lock-up condition.
To control port 85a at one end of the valve 85 is connected a base control pressure line 138 which is connected to the main line 110 through the solenoid reducing valve 88. To interrupt port 85b at the other end of the valve 85 is connected an interrupt line 139 which is connected to the forward line 111. Downstream of an orifice 89 disposed on the base control pressure line 138 is arranged a first duty solenoid valve 90 which adjusts a control pressure to the control port 85a so that a pressure difference between the engaging pressure to the engaging chamber 26a through the converter line 132 and engaging line 136 and the releasing pressure to the releasing chamber 26b through the intermediate line and the releasing line 135 is adjusted to accomplish a desired slip condition of the lock-up clutch 26 provided that the line pressure is not introduced to the interrupt port 85b through the interrupt line 139.
When the line pressure is supplied to the interrupt port 85b of the valve 85 through the line 139, the spool of the control valve 85 is fixed at the left position. In this case, the hydraulic pressure of the lock-up releasing chamber 26a is discharged from the drain port of the control valve 85 through the releasing line 135, fourth shift valve 84 and intermediate line 137 so that a lock-up condition in which the lock-up clutch 26 is fully engaged is established. In the drain port, there is provided an orifice of a predetermined diameter which prevents the hydraulic fluid from excessively flowing out therethrough even if the hydraulic fluid introduced to the engaging chamber 26b through the engaging line 136 is introduced to the releasing chamber 26a.
The first duty solenoid valve 90 operates as follows. As a duty ratio D is increased, a duty control pressure of the first duty solenoid valve 90 is decreased. Therefore, when the duty ratio D is 100%, the drain port of the valve 90 is fully opened so that the pressure level of the base pressure control line 132 is zero downstream of the orifice 89. On the other hand, when the duty ratio D is zero, the drain port is interrupted to maximize the pressure level of the valve 90.
The hydraulic control circuit 60 is provided with a throttle modulator valve 91 and a second duty solenoid valve 92 for controlling a line pressure which is adjusted by the regulator valve 61.
To the throttle modulator valve 91 is connected a line 140 which is connected to the main line 110 through the solenoid reducing valve 88. To a control port 91a at one end is introduced a duty control pressure adjusted by a second duty solenoid valve 92 which is periodically opened and closed to produce a throttle modulator pressure in accordance with a duty ratio D of the valve 92. In this case, the duty ratio D is determined in accordance with, for example, a throttle opening so that the throttle modulator pressure corresponding to the duty ratio D is introduced to a first apply port 61 of the regulator valve 61 through a line 141 to increase the line pressure which is adjusted by the regulator valve 61 in accordance with the throttle valve and the like.
In the illustrated embodiment, the duty control pressure produced by the first duty solenoid valve 90 is also introduced into a control port 93a of a modulator valve 93. The modulator valve adjusts the line pressure introduced from the main line 110 through a line 143 in accordance with the duty control pressure from the first duty solenoid valve 90 to produce a modulator pressure and to introduce the modulator pressure to a back pressure chamber 83a of the N-R accumulator 83 and the like through a line 144.
To a control port 77a of the 3-4 control valve 77 disposed on the 3-4 clutch line is connected a line 145 which is separated from the line 144. Therefore, when the first duty solenoid valve 90 is subjected to a duty control, a modulator pressure is produced in accordance with the duty ratio D and introduced to the port 77a so that a hydraulic pressure (3-4 clutch pressure) which is controlled by the control valve 77 is also controlled to a value corresponding to the duty ratio D.
The 3-4 control valve 77 is provided with an interrupt port 77b at one end for preventing the valve 77 from making a pressure adjusting action (pressure reducing action).
To the interrupt port 77b is connected an interrupt line 146 which is connected to the main line 110 through a switching valve 94 and a line 146. When the line 147 is communicated with the line 146 through the switching valve 94, the line pressure is introduced to the interrupt port 77b of the 3-4 control valve from the main line 110 to prevent the control valve 77 from making the pressure adjusting action.
To a control port 94a at one end of the valve 94 is connected a line 148 separated from the base pressure control line 138 between the orifice and the first duty solenoid valve 90. To a balance port 94b at the other end of the valve 94 is connected a line 149 separated from the line 138 upstream of the orifice 89. When the duty control pressure is greater than a predetermined value, the spool of the valve 94 is shifted to the left position so that the interrupt line 147 is brought into the line 146 to introduce the line pressure of the main line 110 to the interrupt port 77b of the valve 77 through the line 146 to prevent the valve 77 from making the pressure adjusting action. When the duty control pressure produced by the first duty solenoid 90 is reduced below the predetermined value, the spool is moved toward the right position against the resilient force of the spring to separate the interrupt line 147 from the line 146.
To the switching valve 94 is connected a line 150 which is brought into communication with the line 147 when the spool is in the right position. The line 150 is connected to the fourth shift valve 84 and is brought into communication with a line 151 which is connected to the main line 110 through the line 133 when the spool of the shift valve 84 is in the right position. In other words, when the fourth solenoid valve 87 is turned ON to enable a control of the engaging force of the lock-up clutch 26, the line pressure from the main line 110 is introduced to the interrupt line 147 through the lines 133, 151, fourth shift valve 84 and line 150. In the converter condition in which the spool of the valve 84 is in the left position, the line 150 is connected to a drain port of the shift valve 84.
To the switching valve 94 is connected a drain line 152 which is brought into communication with the servo apply line 118 when the spool of the first shift valve 63 is in the right position. The drain line 152 is selectively connected to two drain ports with different flow reduction rates. In the illustrated embodiment, the right hand drain port is smaller than the left hand drain port (in FIGS. 2 and 4).
To the first shift valve 63 is connected a line 153 separated from the interrupt line 147. When the first solenoid valve 66 is turned ON to shift the spool of the shift valve 63 to the left position, the line 153 is brought into communication with the line 154 which is connected to a second back pressure port 74b of the 1-2 accumulator 74 to which the line pressure from the main line 110 is introduced at a first back pressure chamber 74a. Therefore, when the line pressure is introduced to the line 147 and when the spool of the shift valve 63 is in the left position, the line pressure is introduced to the second back pressure chamber 74b of the 1-2 accumulator 74 through the line 152 and the line 153.
To a control port 73a at one end of the accumulation cut valve 73 disposed on the line 119 which is separated from the servo apply line 118 and is connected to the 1-2 accumulator 74 is connected a line 155 separated from the 3-4 clutch line 121 downstream of the 3-4 control valve 77. To an accumulation cut interrupt port 73b at the other end of the valve 73 is connected a line 157 which is connected to the interrupt line 139 for preventing the lock-up control valve 85 from making the pressure adjusting action through a ball valve 95 and line 156. To an intermediate port 73c provided at an intermediate portion of the accumulation cut valve 73 is connected a line 158 separated from the line 126 which is connected to the second shift valve 64. To the ball valve 95 connected to the line 157 which is communicated with the accumulation cut port 73b of the valve 73 is connected a line 158 separated from a line 150 connecting the switching valve 94 with the fourth shift valve 84.
In addition, the hydraulic control circuit 60 is provided with a fifth shift valve 96 for controlling a shift timing. To the shift valve 96 are connected a bypass line 160 bypassing the orifice on the servo apply line 118, a second bypass line 161 bypassing the one way valve 82 on the reverse clutch line 130, and the interrupt line 139 connected to the interrupt port 85b of the valve 85. To a control port 96a at one end of the shift valve 96 is connected a base pressure control line 162 separated from the main line 110. When the fifth solenoid valve 97 is switched ON and OFF to shift the positions of the spool of the shift valve 96, the first, second bypass lines 160 and 161 and the interrupt line 139 are opened and closed.
That is, when the fifth solenoid valve 97 is OFF to place the spool of the shift valve 96 at the right position, the first bypass line 160 and interrupt line 139 are opened whereas the second bypass line 161 is interrupted. In this case, a downstream portion of the second bypass line 161 is connected with the line 129 on which the orifice 80 and one way orifice 81 are disposed. Then, the line 161 is connected to the reverse clutch line 130 or the reverse line 112 through the line 129. On the other hand, when the fifth solenoid 97 is turned ON to move the spool of the shift valve 96 to the left position, the first bypass line 160 and the interrupt line 139 are interrupted whereas the second bypass line 160 is opened.
On the first bypass line 160 is disposed a one way orifice 98 downstream of the fifth valve 96 for reducing a supply flow of the hydraulic fluid to the valve 96 and a normal type of orifice 99 upstream of the fifth shift valve 96. On a line 163 separated from the first bypass line 160 upstream of the orifice 99 is disposed another orifice 100 smaller than the orifice 99 and a one way valve 101 for preventing a supply flow of the hydraulic fluid to the valve 96. The line 163 is connected to the first bypass line 160 downstream of the valve 96 when the spool of the fifth shift valve 96 is positioned at the left position.
As shown in FIG. 3, the automatic transmission 10 is provided with a controller 200 for controlling the first to third solenoid valves 66-68 for shift operation, the fourth solenoid valve 87, first duty solenoid valve 90, fifth solenoid valve 97 and second duty solenoid valve 92. The controller 200 receives signals from a vehicle speed sensor 201, throttle opening sensor 202, shift position sensor 203 for detecting a position of shift lever, engine speed sensor 204 for detecting engine speed, turbine speed sensor 205 for detecting a turbine rotation speed, hydraulic temperature sensor 206 for detecting the temperature of the hydraulic fluid and controls the solenoid valves in accordance with the operating condition or driver's requirement.
With this structure of the automatic transmission 10, for example, in a shift operation where the 3-4 clutch 43 is involved, the 3-4 clutch 43 is controlled by the 3-4 control valve 77 as follows.
Assuming that the lock-up clutch 26 is in the converter condition in the second stage, the fourth solenoid valve 87 which controls the fourth shift valve 84 is turned OFF to position the spool 84a of the shift valve 84 at a left position as shown in FIG. 4. In this position, the line 150 connected to the shift valve 84 through the switching valve 94 is communicated with the drain port 84c of the shift valve 84.
In this case, if the first duty solenoid valve 90 is not actuated, the pressure level of the control line 138 is kept at the maximum value so that a hydraulic force from the control port 94a is added to the spring force acting on the spool 94c of the switching valve 94 rightward in the drawing. As a result, the spool 94c is kept at the left position against the hydraulic force from the left side. In this condition, the interrupt line 147 communicated to the interrupt port 77b of the 3-4 control valve 77 is communicated with the line 146 which is communicated with the main line 110. Thus, the line pressure of the main line 110 is introduced to the interrupt port 77b through the lines 146 and 147. A plug 77c in the 3-4 control valve 77 is urged toward left by virtue of the line pressure so that the spool 77d is also urged toward left by the plug 77c and positioned at the left side. As a result, the input port 77e of the 3-4 control valve 77 is fully communicated with the output port 77f.
With this condition, assuming that the driving condition is changed to produce a 2-3 shift command which is intended to change the shift stage from second to third, the second solenoid valve 67 which controls the second shift valve 64 is turned OFF so that the spool 64b of the second shift valve 64 is moved leftward. In this case, the controller 200 produces a duty control signal to the first duty solenoid valve 90 so as to provide a duty control pressure of the valve 90 with a value smaller than a predetermined value P 0 . As a result, the hydraulic pressure introduced from the balance port 94b of the switching valve 94 becomes greater than that from the control port 94b so that the spool 94c of the switching valve 94 is moved rightward against the spring force from the right side thereof.
Consequently, as shown in FIG. 5, the interrupt line 147 communicated with the interrupt port 77b of the 3-4 control valve 43 is separated from the line 110 communicated with the main line 110 and brought into communication with the line 150 communicated with the fourth shift valve 84. As a result, the line pressure which was introduced to the interrupt port 77b of the valve 43 is discharged from the drain port 84c of the fourth shift valve 84. Accordingly, the plug 77d of the 3-4 control valve 43 is moved rightward by virtue of the spring 77g disposed between the spool 77d and plug 77c allowing the 3-4 control valve 77 to make a pressure adjusting (reducing) action. If the first solenoid valve 90 is controlled based on a predetermined duty ratio D, a modulator pressure is produced in the modulator valve 93 for the accumulator in accordance with the duty ratio D. The modulator pressure is introduced to the control port 77a of the control valve 43. The line pressure introduced to the input port 77e of the valve 77 is adjusted corresponding to the modulator pressure and supplied to the 3-4 clutch valve 43 as a 3-4 clutch pressure. In this case, preferably, the first duty solenoid valve 90 is controlled in accordance with the duty ratio which is changed in a manner that the 3-4 clutch pressure has a leveled pressure condition while changing. This control enables the 3-4 clutch to be brought into full engagement in a short time without producing a torque shock.
When the 3-4 clutch 43 is fully engaged following the entire release of the 2-4 brake 45 and thus the shift operation to the third stage is completed, the duty control signal provides the duty solenoid valve 90 with a duty control pressure greater than a value P 0 . As a result, the spool 94c of the switching valve 94 which is positioned at the right side is moved leftward. Thus, the line pressure from the main line 110 is supplied to the interrupt port 77b of the 3-4 control valve 77 through the line 146 and the interrupt line 147 so that the plug 77c of the valve 77 is moved leftward and the spool 77d is kept at a position where the input port 77e is brought into full engagement with the output port 77f. As a result, the line pressure from the forward line 111 which is introduced to the control valve 77 from the second shift valve 64 through the 3-4 clutch line 121 is introduced to the 3-4 clutch 43 without reducing the pressure level and thus the clutch 43 is surely engaged.
As aforementioned, the switching valve 94 disposed between the interrupt line 147 communicated with the interrupt port 77b of the 3-4 control valve 77 and the line 146 communicated with the main line 110 is so actuated that the interrupt line 147 is brought into communication with the line 146 when the duty control pressure due to the first duty solenoid valve 90 is greater than the value P 0 . As a result, the engaging pressure of the 3-4 clutch 43 is changed versus the duty control pressure controlled by the first duty solenoid valve 90 in accordance with a characteristic as shown in FIG. 6. That is, the engaging pressure is variably controlled in a range X where the control pressure is smaller than a value P 0 and kept at the maximum value which is the same value as the line pressure in a range Y where the control pressure is greater than the value P 0 . Accordingly, a control range R can be reduced in the range X so that the engaging pressure can be precisely controlled during the shift operation in accordance with the driving condition.
If the converter condition is switched to the slip condition in the control of the lock-up control in the case where the 3-4 clutch 43 is engaged, the fourth and fifth solenoid valves 87 and 97 are turned ON. As a result, the spools of the shift valves 84 and 85 in the hydraulic circuit 60 of FIG. 2 are moved rightward and leftward respectively. Thus, the converter line 132 communicated with the fourth shift valve 84 is communicated with the engaging line 136 communicated with the engaging chamber 26b of the lock-up clutch 26 as shown in FIG. 7. Concurrently, the intermediate line 137 communicated with the lock-up control valve 85 is brought into communication with the releasing line 135 which communicates with the releasing chamber 26a of the lock-up clutch 26. The interrupt line 139 which supplies the line pressure of the forward line 111 to the interrupt port 85b of the lock-up converter 85 is interrupted by the fifth shift valve 96 so that the hydraulic fluid downstream of the valve 96 is exhausted from the drain port. Thus, the control pressure introduced to the control port 85a which is positioned opposite to the interrupt port 85b with regard to the spool 85c is controlled by the first duty solenoid valve 90 so that the hydraulic pressure in the converter line 132 communicated with lock-up control valve 85 is introduced to the intermediate line 137 after the pressure is adjusted corresponding to the duty control pressure. The output pressure of the converter line 132 is introduced to the releasing chamber 26a of the lock-up clutch 26 through the intermediate line 137, fourth shift valve 84 and releasing line 135 as a releasing pressure. On the other hand, to the engaging chamber 26b of the lock-up clutch 26 is directly introduced the hydraulic pressure of the converter line 132 which is introduced to the fourth shift valve 84 through the engaging line 136 as an engaging pressure. Thus, the lock-up clutch 26 is subjected to the slip control in accordance with the pressure difference between the engaging and releasing pressures.
In this case, the spool 84b of the fourth shift valve 84 is positioned at the right side so that the line 151 communicated with the line 110 through the line 133 is brought into communication with the line 150 which is communicated with the switching valve 94. Accordingly, even where the duty control pressure of the first duty solenoid valve 90 is reduced below the predetermined pressure P 0 due to the slip control so that the spool 94c of the switching valve 94 is positioned at the right side, the line pressure of the main line 110 introduced to the line 151 is introduced to the interrupt port 77c of the 3-4 control valve 77 through the line 150, switching valve 94 and interrupt line 147 so as to prevent a pressure reducing action due to the movement of the spool 77d. Thus, the 3-4 clutch 43 can be kept engaged without failure.
Although the present invention has been explained with reference to a specific, preferred embodiment, one of ordinary skill in the art will recognize that modifications and improvements can be made while remaining within the scope and spirit of the present invention. The scope of the present invention is determined solely by the appended claims.
|
A control system of an automatic transmission includes a torque converter, a lock-up clutch for directly connecting input and output members of the torque converter, a pressure control valve which changes a hydraulic pressure to control an engaging force of the lock-up clutch, and a pressure regulator, disposed in an engaging passage, which supplies hydraulic pressure to engage a frictional element. The pressure regulator adjusts a primary pressure and produces an output hydraulic pressure corresponding to a control pressure introduced into a control port of the pressure regulator. A control pressure supply device is provided for introducing the control pressure, controlled by the pressure control valve, into the control port of the pressure regulator. The number of parts can be reduced without producing any inconvenience.
| 8
|
FIELD OF THE INVENTION
This invention relates generally to the field of battery chargers, and more particularly to the detection of battery faults.
BACKGROUND OF THE INVENTION
In order to provide protection against power outages, modern computer systems typically use battery backups. When the AC voltage supplied by a computer's power supply to the computer drops below a certain voltage level, a trigger circuit causes a battery to act as an alternative power source. This allows the computer to save its memory contents during the outage, and if possible, to perform an orderly shutdown. Alternatively, a battery backup system may allow for complete operation of the computer system until AC voltage is restored.
Typically, the battery voltage is supplied by a plurality of battery packs, each containing a plurality of battery cells (usually 6). A battery charger must keep the battery packs charged to assure that the battery will be able to supply the proper level of voltage and energy to the computer when necessary.
Each minute of lost power to a computer system which supports a critical task (for example, processing bank transactions) could result in a loss of hundreds of thousands of dollars. The battery backup helps to minimize these losses and add reliability to the computer system. However, in the event that one battery is damaged, either by a short circuited cell or a by cell with increased impedance, the battery packs may not be able to support the computer system when required. Presently, the deterioration of a battery becomes apparent only when it fails to adequately support the computer system when requested, and data is lost. It would be desirable to have notification of the impending failure of a battery backup system before vital information and computing time is lost.
SUMMARY OF THE INVENTION
According to the invention a battery charger for charging a plurality of batteries includes a voltage supply connected by a pair of switches to a power converter. The power converter includes a transformer having a primary winding and a plurality of secondary windings. Each secondary winding is coupled to a battery. Voltage is transferred from the voltage supply to the primary winding when the switches are closed and current is transferred from the secondary windings to the batteries when the switches are open.
Charge control circuitry monitors the voltage of each battery and the total battery voltage and determines the amount of current to supply to the batteries. The charge control unit operates in two modes: voltage mode and current mode. When the total battery voltage reaches a predetermined voltage limit, termed the "float voltage", the batteries are considered charged and the charge control circuitry operates in voltage mode. In voltage mode, a minimum current which is required to maintain the battery voltage at float voltage is supplied to the batteries. When the voltage of either battery falls below float voltage, the batteries require charging and charge control unit operates in current mode. In current mode, the charge control circuitry continuously delivers a maximum allowable current (subject to component tolerance) to the batteries until the predetermined voltage limit is again attained. The total current delivered to the batteries is apportioned between the batteries, with the batteries at a lower charge state drawing more of the charging current than the batteries with a higher charge state. The batteries with a lower charge state continue to draw higher proportions of the current until the state of charge of all batteries in the backup system is equal, at which point all the batteries draw equal current. When the batteries have been charged to float voltage, they require less current than that which is being supplied in current mode to maintain float voltage, and the charge control unit reverts to voltage mode.
Supervisory logic monitors the current received from the secondary windings by each of the batteries and the voltage of each of the batteries to determine the charge status of each battery and the operating status of the power converter. If one battery continues drawing a greater proportion of the maximum current relative to the remaining batteries after the predetermined voltage limit has been reached, this indicates two possible fault conditions in the battery backup system. The first possible fault condition is that there is a short circuited cell causing one battery to draw a greater proportion of current. The second possible fault condition is that there is a cell with high impedance causing one battery to draw a smaller proportion of current. For both fault conditions, the supervisory circuit detects the current imbalance and generates a shutdown signal. The shutdown signal is also asserted when the supervisory circuit detects an over voltage condition in any of the batteries, which could potentially increase temperatures in the battery charger and damage components. In addition, the shutdown signal is asserted in the event of an over current in the primary winding of the power converter caused by failure of the battery charger. The shutdown signal precludes further operation of the charge control circuit for a predetermined time period and alerts the system operator of a problem within the battery backup system.
Thus, the present invention allows for detection of faults within a battery backup system, thereby providing means for avoiding the loss of vital information and expensive computing time by allowing for correction of the fault condition before damage results.
Other objects, features and advantages of the invention will become apparent from a reading of the description of the preferred embodiment when taken in conjunction with the drawings in which like reference numerals refer to like elements in the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating a battery backup system embodying the invention;
FIG. 2 shows waveforms illustrating operation of the system shown in FIG. 1;
FIG. 3 is a schematic diagram of the charge control unit in FIG. 1;
FIG. 4 is a schematic diagram of the supervisory logic in FIG. 1; and
FIG. 5 shows voltage and current relationships illustrative of operation of the charge control unit shown in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 shows the basic components of a battery backup system embodying the present invention suitable for use in a computer system. A voltage source 10 supplies a d.c. input voltage to a power conversion unit 20, across the input terminals of which a reservoir/filter capacitor is connected. The power conversion unit 20 includes a transformer 120 with a primary winding 24 and, for example, two secondary windings 26 and 28. The primary winding 24 is connected to the terminals 10 and 11 by MOSFET power switches 14 and 16 respectively and also by clamp diodes 25 and 23 respectively. The secondary windings 26 and 28 are coupled to batteries 36 and 38 respectively.
The operative position of the switches 14 and 16 is controlled by the value of a signal SWITCH CTRL on line 208 which is a signal provided by a charge control unit 40. Voltage from the voltage source 10 is applied to the primary winding 24 of the transformer 20 during a period Ton when switches 14 and 16 are in a closed position (or conducting). During a period Toff when the switches 14 and 16 are in an open position (or non conducting), current is transferred from the primary winding 24 to the secondary windings 26 and 28. The current from each secondary winding 26 and 28 is subsequently transferred to charge its respective battery 36 and 38 to a nominal float voltage of 54.5 volts. The charge control unit 40 continuously cycles the switches 14 and 16 between the open and closed positions during successive switching cycles Ts=Ton+Toff. Energy is transferred from the voltage source 10 to the primary winding 24 when the switches 14 and 16 are closed. This energy is delivered to the secondary windings 26 and 28 when the switches 14 and 16 are open for delivery to the batteries 36 and 38. In the preferred embodiment, the time period for the switching cycle can vary between 19.6 microseconds and 22.2 microseconds, the variation being due to component tolerances.
The discharge of the batteries 36 and 38 occurs when an SCR 30 receives a trigger signal from a trigger circuit 32. The trigger circuit 32 activates the SCR if a.c. power to the load 50 (e.g. a computer) fails. When this occurs, the power converter supply voltage 10 (also derived from the a.c. power supply) also fails so the charge control unit 40 is inhibited and the SCR 30 turns on, causing the battery energy to be transferred to the load 50 at output 34. The load utilizes the voltage from the batteries 36 and 38 to perform an orderly shutdown or to provide a back up supply to the load completely until the a.c. power returns (or until the batteries become discharged). When the power supply returns, the charge control unit 40 is again activated and operation of the power converter recommences.
Supervisory logic 60 monitors the voltage of each battery (VB1 and VB2) on lines 100 and 102 and the voltage generated across each battery current measurement resistor 21 and 22 (IB1 and IB2) on lines 104 and 106 to ensure that the power conversion unit 20 and the batteries 36 and 38 are operating as expected. In the event that the power conversion unit 20 or the batteries 36 and 38 are faulty, the supervisory logic 60 asserts a SHUTDOWN signal on line 108. Assertion of the SHUTDOWN signal effects shutdown of the power converter and stops battery charging. A more detailed discussion of the faults recognized by the supervisory logic 60 will be discussed later in the specification.
Power Converter
Operation of the power converter 20 shown in FIG. 1 will be described with reference to the operating waveforms shown in FIG. 2.
At the start of a switching cycle Ts, there is no current flowing in either the transformer primary winding 24 or secondary windings 26 and 28. During a period Ton, (FIG. 2a) when the switches 14 and 16 are closed by the signal SWITCH CONTROL on line 208, the voltage source 10 is applied to the primary winding 24 (FIG. 2b). The voltage source 10 is positive referred to ground 11. The secondary windings 26 and 28 reflect this voltage. The voltage which is reflected across the transformer secondary windings 26 and 28 is equal to the voltage of the voltage source 10 multiplied by the ratio of secondary winding turns to primary winding turns. Output rectifiers 12 and 13 are electrically oriented such that a reverse bias voltage is applied to these devices while the switches 14 and 16 are closed, precluding the conduction of current to the secondary windings 26 and 28. Therefore, no energy is transferred from the primary winding 24 to the secondary windings 26 and 28 while the switches 14 and 16 are closed.
During the time period (Ton) that the switches 14 and 16 are closed, the current in the primary winding increases as shown in FIG. 2c, according to the following equation, where Iprim is the primary winding current, Vin is the voltage of the voltage supply 10, and Lprim is the primary winding magnetizing inductance of the power transformer 120:
Iprim=(Vin×Ton)/Lprim
Iprim, the current of the primary winding 24, is monitored by a second transformer 37. The output from the secondary winding 29 of this transformer is used by the supervisory logic 60 and will be discussed later in this specification.
When the switches 14 and 16 are subsequently opened (for time Toff, FIG. 2a) the current in the primary winding 24 must continue to flow until it is transferred from the primary winding 24 to the secondary windings 26 and 28. To continue current flow, the current is conducted through clamp diodes 23 and 25 back to the voltage source 10. Hence, in order to maintain current flow, the voltage across the primary winding 24 is reversed (FIG. 2b), effectively causing the current in the primary winding to decay (FIG. 2c) and the current in the secondary windings 26 and 28 to increase (FIG. 2a) until current flow ceases in the primary winding 24.
At this point, virtually all of the energy which was stored in the primary winding 24 has been transferred to the secondary windings 26 and 28. When the current in primary winding 24 has decayed to zero, clamp diodes 23 and 25 stop conducting and the secondary winding current is delivered to the combination of the capacitors 15 and 17 and the batteries 36 and 38. The total current carried by each of the secondary windings 26 and 28 at this point is defined by the below relationship, where Is the total secondary winding current, N1 is the number of turns of the primary winding 24, N2 is the number of turns of each secondary winding of the transformer:
Is=(N1/N2)Iprim
In the preferred embodiment, each secondary winding 26 and 28 has four turns, while the primary winding has 10 turns. The amount of current which is delivered by each secondary winding 26 and 28 to the batteries 36 and 38 is determined by the amount of current that each battery 36 or 38 will accept at its particular charge voltage level. After a given period of time termed td (FIG. 2d), the current delivered by each secondary winding 26 and 28 decays to 0. The switching cycle (Ts=Ton+Toff) is advantageously designed such that Toff is always greater than td to allow for complete delivery of the transformer secondary winding current to the batteries before the start of the next switching cycle. After the secondary winding current has decayed to 0, the current is supplied to the batteries 36 and 38 by the capacitors 15 and 17 until the next switching cycle.
Charge Control Unit
As mentioned previously, the charge control circuit 40 controls the cycling of the switches 14 and 16. The longer that the switches 14 and 16 are closed (Ton), the greater the amount of energy transferred to the primary winding 24 and hence the greater amount of current delivered to the secondary windings 26 and 28 and batteries 36 and 38 when the switches 14 and 16 open (Toff). By controlling the duty cycle of the switches 14 and 15, that is the ratio between Ton and (Ton+Toff), the charge control circuit 40 controls the amount of current delivered to the batteries 36 and 38.
Modes of Operation
The charge control unit 40 operates in two modes, current mode and voltage mode. In voltage mode, the voltage of both batteries 36 and 38 is equal to a predetermined limit, called the float voltage. When a healthy battery has been charged to the float voltage, very little current is needed to maintain this voltage. This small amount of current is termed the float current. For example, in the preferred embodiment, to maintain a float voltage of 54.5 V per battery at 25 degrees C, the total float current drawn by two healthy batteries would probably be in the region of 0-100 mA.
If either battery 36 or 38 is in a discharged state, it will require a greater current than the float current to regain float voltage. The charge control unit 40 controls the switches 14 and 16 to increase the current supplied to the batteries 36 and 38. The supervisory logic 60 monitors the increase of current to the batteries to determine when the charge control unit 40 is operating in current mode. The supervisory logic considers the charge control unit 40 to be in current mode when the current being delivered to the batteries exceeds a threshold range of 4.58 to 4.87 Amps. Because the power delivery capability of the charger is limited, it cannot supply greater than 5.0 to 5.36 Amps while maintaining float voltage. Therefore, in current mode, the voltage of the batteries 36 and 38 is allowed to drop below the float voltage while the total current supplied to the batteries 36 and 38 is increased to deliver the maximum allowable current (5.0 to 5.36 Amps based on component tolerances) to the batteries.
The battery voltages VB1 and VB2 might be as low as 35 V for an extremely discharged battery or as high as 48 V for batteries which have not been significantly discharged. As current is returned to the batteries 36 and 38, the charge control unit 40 continues operating in current mode and the voltages VB1 and VB2 of the batteries 36 and 38 each increases. If, for example, battery 36 initially has a lower charge state than battery 38, battery 36 will accept a greater proportion of the total current. As its charge gradually approaches the charge state of battery 38, both batteries 36 and 38 will accept a similar portion of the total charging current. When both battery voltages VB1 and VB2 equal the float voltage, the charge control unit 40 resumes operation in voltage mode and the total current supplied by the charge control unit 40 decreases to float current level.
Functional Description
Referring again to FIG. 1, the charge control unit 40 employs the battery voltages (VB1 on line 100 and VB2 on line 102) and the voltages generated across the battery current measurement resistors 21 and 22 (IB1 on line 104 and IB2 on line 106) in determining the duty cycle of the switches 14 and 16.
Referring now to FIG. 3, the opposite polarity voltages IB1 and IB2 are input to a current measurement circuit CMC, filtered, and summed by an operational amplifier 43 to produce an output voltage ITOTAL on line 142. The voltage ITOTAL is exactly proportional to the total battery current.
The battery voltages VB1 and VB2 are input to the voltage measurement circuit VMC, filtered, and summed by an operational amplifier 45 which converts the positive and negative polarity voltages (VB1 positive, VB2 negative) into a positive output voltage VBAT on the line 144 which is proportional to the sum of the absolute value of both voltages.
VBAT is input to the voltage error amplifier 46 and compared with a voltage reference input VREF1 from line 148. VREF is a temperature compensated voltage representing the battery float voltage. In the embodiment being described, VREF varies between 4.46 and 4.48 volts over a temperature range of 16°-50° C.
VBAT on line 144 and VREF1 on line 148 are compared in the voltage error amplifier VEA by an operational amplifier 47. A filtered output voltage VERR on line 147 is proportional to the voltage difference between VBAT and VREF1. The voltage VERR is fed into the limiter 50, which uses an operational amplifier 49 and a diode 51 to produce an output voltage IDEM on line 146. The value of IDEM is limited to 5.1 volts (which is the temperature independent value of VREF2) to ensure that no more than 5.36 Amps of current (the maximum possible current due to component tolerances in the preferred embodiment) is required from the secondary windings 26 and 28. Thus IDEM is a voltage which represents the discharge status of the batteries 36 and 38.
The limiter circuit 50 acts as follows: when the batteries 36 and 38 are fully charged, VERR is less than 5.1 V and the value of IDEM on line 146 (unchanged by the limiter circuit 50) is equal to the value of VERR. At this point, the batteries 36 and 38 can be maintained at float voltage by a charging current of less than 5.0 to 5.36 Amps. However, if the batteries 36 and 38 are significantly discharged, more than 5.0 to 5.36 Amps would be required to maintain the batteries 36 and 38 at float voltage. This required current is represented in the voltage value of VERR, which would exceed 5.1 Volts. The value of IDEM, however, is limited to 5.1 Volts by the limiter circuit 50, thereby limiting the charge current requested to 5.0-5.36 Amps and causing the voltage of the batteries 36 and 38 to fall below the float voltage. At this point, the charge control unit 40 is operating in a current mode (FIG. 5).
As the batteries are charged, the voltage difference between VBAT and VREF, represented by VERR, will fall below 5.1 volts, at which point IDEM will no longer be limited to 5.1 V by the limiter circuit 50, but will track the value of VERR. Thus, as the batteries 36 and 38 reach float voltage, VBAT equals VREF, and the charge control unit 40 returns to voltage mode.
It is the comparison of IDEM on line 146 (representing the voltage difference between the float voltage and the sum of the voltages of the batteries 36 and 38) with ITOTAL on line 132 (the voltage representing the sum of the current flows through the current measurement resistors 15 and 17) which creates a feedback loop for controlling the duty cycle of the switches 14 and 16. This comparison is made by the current error amplifier 52. When IDEM is equal to ITOTAL, the batteries 36 and 38 are getting either the correct amount of current to maintain the float voltage (in voltage mode) or the current limit of 5.0 to 5.36 Amps (in current mode). When IDEM is smaller than ITOTAL, the amount of current delivered to the batteries 36 and 38 should be decreased, until ITOTAL is equal to IDEM. Likewise, when IDEM is greater than ITOTAL, the amount of current delivered to the batteries 36 and 38 should be increased. The amount that ITOTAL should be increased or decreased to align with IDEM is indicated by a voltage VCON on line 152 representing the difference between the two voltages, derived with an operational amplifier 53 wired as a high gain amplifier.
As stated previously, the amount of time that the switches 14 and 16 are closed (Ton) dictates the amount of current in the primary winding 24, and subsequently the amount of current delivered to the batteries 36 and 38. VCON is utilized by a pulse width modulator 54 in determining the duty cycle (Ton/(Ton+Toff) of the switches. The larger VCON, the higher the duty cycle ratio, up to a maximum of 49% (wherein the switch is closed for slightly less than half of the total switching cycle). The pulse width modulator 54 utilized in the present invention also has the capability of being shut down. This functionality is utilized by the supervisory logic 60 as will be described later in the specification. The pulse width modulator 54 thus controls the value of SWITCH CTRL on line 108, controlling the cycling of the switches 14 and 16 and subsequently the delivery of secondary winding current to the batteries 36 and 38.
Supervisory Logic
Referring now to FIG. 4, the supervisory logic 60 is shown. The supervisory logic 60 performs a variety of functions, including: monitoring the batteries 36 and 38 for an overvoltage condition, determining whether the charge control unit 40 and power converter 20 are functioning correctly, detecting possible overcurrent in the transformer primary winding 24 and determining that either of the batteries 36 or 38 is damaged or degraded. The supervisory logic 60 functions to assert the signal SHUTDOWN on line 108 in the event that any of the above listed conditions occur, or if a shutdown is requested by an external user. Each functional unit of the supervisory logic 60 operates using +12 v and -12 v bias voltages to drive logical output signals.
A battery voltage detector BVD monitors VB1 and VB2 to detect if the voltage of either battery 36 or 38 either exceeds a voltage (battery overvoltage threshold) which is too high for safe and reliable operation (in the range of 67 to 70 volts) or drops below a battery undervoltage threshold which is always less than the float voltage over all operating temperatures (approximately 50.5 to 52.7 volts). The battery voltage detector 62 generates two output signals BATOV on line 162 (output from comparator 62A or 62B) and BATUV on line 163 (output from comparator 63A or 63B) both of which equal +12 volts if VB1 and VB2 exceed the float voltage but are under the overvoltage range. However, if the voltage of either of the batteries 36 and 38 exceeds the 67-70 volt range BATOV is pulled down to -12 volts. Likewise, BATUV is also pulled down to -12 volts if the voltage of either battery 36 or 38 drops below the battery undervoltage threshold (approximately 50.5 to 52.7 volts). Thus, BATOV and BATUV notify other functional blocks within the supervisory logic 60 whether the voltages of the batteries 36 and 38 have deviated from the desired voltage range.
Similarly, a battery current detector BCD monitors ITOTAL to detect when the total battery current deviates from a maximum current threshold (4.58-4.87 amps). At the output of an comparator 64, the battery current detector BCD generates a voltage ITOT -- H, which is equal to +12 v when ITOTAL indicates that the total current being drawn by the batteries exceeds the maximum current threshold. However, if ITOTAL indicates that the current drawn by the batteries 36 and 38 is less than the maximum current threshold, the signal ITOT -- H is pulled down to -12 v. Thus ITOT -- H indicates to what extent the batteries 36 and 38 are being charged.
ITOT -- H and BATUV are utilized by the charger ok detector CHD to determine if the charge control unit 40 is operating as expected. The charger ok detector CHD indicates normal or abnormal charger operation by generating a signal MDOK on line 166. If the batteries are below the float voltage, as indicated by BATUV having a value of -12 v, then likewise, the batteries 36 and 38 should be drawing a current which is greater than the maximum current threshold, as indicated by ITOT -- H having a value of +12 v. As the batteries 36 and 38 are charged, the battery voltage increases until both battery voltages exceed the battery undervoltage threshold, at which point BATUV will equal +12 V. At this point, the charger is still delivering the maximum allowable current of 5.0 to 5.36 Amps to the batteries, and therefore both BATUV and ITOT -- H are equal to +12 V. As the charging continues, the battery current gradually decreases below the current threshold of 4.57 to 4.87 Amps, and the charge control unit 40 resumes operation in voltage mode. Because the current has dropped below the current threshold, ITOT -- H is pulled down to -12 V, while BATUV remains equal to +12 V.
Normal charger operation is indicated by MDOK being equal to +12 V, which occurs during the three conditions described above: when either ITOT -- H OR BATUV are equal to +12 V, or when both ITOT -- H and BATUV are equal to +12 V. However, if the voltage of either battery 36 and 38 is less than the battery undervoltage (BATUV equal to -12 V), and the charging current is less than the current threshold (ITOT -- H equal to -12 V), abnormal charger operation is indicated by MDOK being equal to OV. MDOK is thereby available as a signal to indicate abnormal charger operation as may be desired.
BATUV and ITOT -- H are also combined by the charge rate detect circuit CRD (which employs a comparator 68) to ascertain whether the charge control unit 40 is operating in current mode or voltage mode. If BATUV is equal to +12 v and ITOT -- H is equal to -12 v, then the voltages of the batteries 36 and 38 are above the float voltage, the batteries are drawing less current than the maximum current detection threshold level, and the charge control unit 40 is operating in voltage mode. The charge rate detect circuit CRD generates FLOAT H on line 168, which is equal to +12 v when the charge control unit is operating in voltage mode, and -12 v when the charge control unit 40 is operating in current mode. FLOAT H is available as a signal to indicate available battery capacity as may be desired.
Referring now to FIG. 1, transformer 37 produces a current in its secondary winding 29 which is one hundredth of the current in its primary winding 27. The current in primary winding 27 is exactly equal to the current in primary winding 24. The current of the secondary winding, PRIM -- CUR on line 209, is fed into the primary overcurrent detector POD, as shown in FIG. 4. The primary overcurrent detector POD includes a comparator 70 to detect if the current in the transformer primary winding 24 exceeds a predetermined limit, for example 9.1 amps. An overcurrent in the primary winding 24 could result from a short circuit in the primary winding 24 or a failure in the charge control unit 40. The primary overcurrent detector POD generates PRIM -- OC, which is equal to -12 v when the current in the primary winding 24 is below the predetermined limit, and is pulled down to -12 v if the current exceeds the predetermined limit.
An imbalance detector IMBD detects a fault condition of either battery 36 or 38. There are two battery failure conditions that are detected by the imbalance detector IMBD. The first arises when the impedance of a battery or that of a cell increases significantly. Increased cell impedance can cause the battery to be incapable of providing current during the next discharge and can cause the cell to be reversed in voltage, subsequently overheating the cell and battery beyond a safe operating temperature. During recharge, if one of the batteries has a high impedance cell, it will accept less charging current than the other normally operating battery at the same charging voltage. This condition persists until the battery voltages exceed the float voltage level. If the current imbalance is such that the normally operating battery draws two thirds of the total charging current when the battery voltages exceed the float voltage level, then an imbalance condition is detected by the imbalance detector IMBD.
The second fault condition arises when one or more battery cells become short circuited. A short circuited cell can result in an increase in the cell's temperature beyond a safe operating temperature during a high current discharge and it can impair the overall discharge capacity of the battery. During recharge, if one of the batteries has a short circuited cell, then it will accept more current than the normally operating battery. An imbalance condition is detected if the short circuited battery draws more than two-thirds of the total charging current when the battery voltages reach the float voltage level.
The imbalance condition is detected by the imbalance detection circuit IMBD as follows. The current delivered to each of the batteries 36 and 38 is determined by the voltages IB1 and IB2 generated across each of the current measuring resistors 21 and 22 as shown in FIG. 2. The voltages IB1 and IB2 generate 0.1 v per amp of battery current. IB1 represents the current in battery 36 and is negative in polarity, while IB2 represents the current in battery 38 and is positive in polarity. Two amplifiers 71 and 73 multiply and filter IB1 and IB2. Each amplifier 71 and 73 produces an output voltage, IBAT1 on line 171 and IBAT2 on line 173. The voltage IBAT1, which is positive in polarity, is directly proportional to the current of battery 36; IBAT1 increases by 1.36 volts for each amp of current in battery 36. Likewise, the voltage IBAT2, which is negative in polarity, is directly proportional to the current of battery 38; IBAT2 decreases by 1.36 volts for each amp of current in battery 38. IBAT1 and IBAT2 are compared with the correct polarity of the reference voltage VREF by comparators 76 and 77. If either IBAT1 exceeds 5.1 v or if IBAT2 exceeds -5.1 v, then either battery 36 or battery 38 is drawing 50% more current than expected (i.e. two thirds of the total current instead of one half) and the wire ORed output IRESULT floats to +12 v. For example, if the total delivered current is 5.0 amps, each battery is expected to draw half, or 2.5 amps. A battery drawing 50% greater current draws 3.75 amps. IBAT1 and IBAT2 increase by 1.36 volts for each amp of battery current, 1.36×3.75=5.1 volts.
If the charge control unit 40 is operating in current mode, and one battery is at a significantly lower discharge state than the second battery, it may feasibly accept 50% greater current than expected. This is allowable in current mode. However, neither battery 36 nor 38 should continue to draw 50% greater current when the voltages (VB1 and VB2) of both batteries 36 and 38 are above float voltage. BATUV is maintained at +12 volts when VB1 and VB2 are above float voltage, as described above with reference to the battery voltage detector circuit 62. BATUV in conjunction with diode 79 enables passage of the signal IRESULT when VB1 and VB2 are above float voltage.
If IRESULT is equal to +12 v and BATUV is equal to +12 v, then there is a fault condition in either battery 36 or 38. The signal IMBALANCE at the output of comparator 78 is wire ored with PRIM -- OC (the fault condition indicating an overcurrent in the primary winding 24) and BATOV (the fault condition indicating an overvoltage condition of either battery 36 or 38), generating the signal INTERNAL SHUTDOWN. It should be noted that if both batteries 36 and 38 fail in the same manner, there may not be an imbalance between the currents drawn by each battery 36 and 38, and therefore neither the IMBALANCE signal or the INTERNAL SHUTDOWN signal will be asserted.
INTERNAL SHUTDOWN, and EXTERNAL -- SHUTDOWN (a shutdown signal provided by an external operator) signal a shutdown control circuit 80 to shutdown the charger by shutting down the pulse width modulator 54 in charge control unit 40. The EXTERNAL -- SHUTDOWN signal advantageously enables an external operator to stop the charger without any internal faults in the battery charger. If either INTERNAL SHUTDOWN or EXTERNAL -- SHUTDOWN is asserted, a signal SHUTDOWN on line 108 is pulled up to +12 v. SHUTDOWN effectively precludes the pulse width modulator 54 from producing pulses, hence stopping the cycling of the switches 14 and 16 and subsequently stopping delivery of current to the batteries 36 and 38. The shutdown of the charger may cause the fault condition to be removed, for example, the voltage of a battery 36 or 38 which exceeded the overvoltage limit will fall below that limit and therefore the BATOV signal is latched so that the SHUTDOWN signal continues to be asserted until bias power to the circuit has been removed and reapplied. The SHUTDOWN signal also is applied to an input of the comparator 66 in the charge OK detector CHD causing the signal MDOK to be pulled down to -12 v. A timer 82 controls the deassertion of SHUTDOWN after the fault condition has been removed from the charger. The timer 82 ensures that the battery charging system will be shutdown for a minimum of two seconds before starting a restart sequence. A persistent fault condition will cause a continuous restart and shutdown sequence of the battery charger, which alerts the operator of a problem in the battery backup system.
In the above described embodiment, the amplifiers 43,45,47,49,53,66,71 and 73 suitably may be Type LM358 low power dual operational amplifiers manufactured by National Semiconductor Corporation, Santa Clara, Calif. The comparator 62A,62B,63A,63B,64,68,70,76,77 and 78 may suitably be Type LM393 devices also manufactured by National Semiconductor Corporation.
Various modifications of the above described embodiment may be made. For example, although described in relation to a charging system for two batteries, embodiments employing three or more batteries could be constructed, using an additional secondary winding for each additional battery. The fault detection circuit could then be modified to provide for detection of imbalance conditions arising from one or more batteries drawing more than a normal range of charging current, and initiation of appropriate safeguard procedures as described herein. Also, the number of cells or batteries in each battery pack such as 36 and 38 is not fixed, subject to each secondary winding of the transformer 120 being connected to the same battery load. The float voltage, i.e. the voltage applied by the charging circuit to the batteries under voltage mode operation of the charge control unit, would require corresponding modification and the current level delivered by the charger in the current mode of the charge control unit might possibly also require modification. While the embodiment specifically described herein is intended for use in conjunction with sealed lead-acid batteries, with modifications dependent on battery characteristics, it could be used with other battery chemistry types.
Thus, an apparatus for detecting faults within a battery backup charging system has been introduced. The present invention provides means for enabling early detection of battery failure before critical data and computing time is lost.
While there has been shown and described a preferred embodiment of this invention, it is to be understood that various adaptations and modifications may be made within the spirit and scope of the invention as defined by the claims.
|
According to the invention a battery charger for charging a plurality of batteries includes a voltage supply connected by a pair of switches to a power converter including a transformer having a primary winding and a plurality of secondary windings. Each secondary winding is coupled to a battery. Voltage is transferred from the voltage supply to the primary winding when the switches are closed and current is transferred from the secondary windings to the batteries when the switches are open. Charge control circuitry monitors the voltage of each battery and the total battery voltage and determines the amount of current to supply to the batteries. Supervisory logic monitors the current received from the secondary windings by each of the batteries and the voltage of each of the batteries to determine the charge status of each battery and the operating status of the power converter. If one battery continues drawing a greater proportion of the maximum current relative to the remaining batteries after the predetermined voltage limit has been reached, this indicates that there is a short circuited cell causing one battery to draw a greater proportion of current or that there is a cell with high impedance causing one battery to draw a smaller proportion of current. For both fault conditions, the supervisory circuit detects the current imbalance and generates a shutdown signal. The shutdown signal is also asserted when the supervisory circuit detects an over voltage condition in any of the batteries, or an over current in the primary winding. The shutdown signal subsequently precludes further operation of the charge control circuit for a predetermined time period, alerting the system operator of a problem within the battery backup system, and avoiding the loss of vital information and expensive computing time by allowing for correction of the fault condition before damage results.
| 8
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/313,504, filed Mar. 12, 2010, which is incorporated herein by reference in its entirety.
BACKGROUND
1. Field of the Disclosure
The present invention generally relates to drinking vessels for containing and dispensing its contents such as beverages. More particularly, this invention relates to drinking vessels having an improved structure that includes an opening for dispensing the contents from the drinking vessel and has an additional opening for venting air into the drinking vessel. The structure further includes a closure for sealing both openings and a fluid flow interrupter for mixing the beverage in the vessel.
2. Description of Related Art
There are numerous portable drinking vessels which are commonly sold and used for the containment of beverages such as water, juice, soft drinks or shakes. Typically, such containers have a lid which covers an opening through which the vessel is filled. The lid often includes an opening for dispensing the contents from the vessel. However, it is desirable for the vessels to also include a vent opening in order to equalize the internal air pressure of the container and thus, allow the user to more easily withdraw the beverage from container. Without establishing such equilibrium, the vacuum created within the container makes it more difficult to generate the flow of the contents out of the vessel. The addition of a vent opening allows air to pass in and out of the drinking vessel and equalizes air pressure during extraction of its contents through the dispensing opening. Therefore, drinking vessels often require a vent opening in order to operate efficiently; however, when not in use, the dispensing opening and vent opening must be sealed to prevent undesirable spilling or leakage of the contents from the vessel which is undesirable to the user or consumer.
Various closure means have been implemented for these drinking vessels but such approaches have had certain shortcomings which prevent them from achieving a totally satisfactory solution. Often, such closure means do not always provide a fluid-tight closure of the openings and therefore provide an avenue by which the contents can escape unintentionally from the drinking vessel. Accordingly, it would be desirable to provide a drinking vessel with a closure that creates a fluid-tight seal with the vent opening.
In addition, problems arise with current drinking vessels when the beverage begins to settle toward the bottom of the drinking vessel. Upon settling, the beverage, such as orange juice, within the drinking vessel is no longer properly mixed to the user's taste preferences. In other instances, powders or the like are blended into a liquid carrier while both are within the drinking vessel itself. It would be desirable to provide a portable drinking vessel that allows the user to have the capability of remixing or initially stirring the contents within the drinking vessel without the need to remove the contents from the container body or mix them prior to entry into the container.
SUMMARY
In accordance with an embodiment of the present invention, a drinking vessel is provided which includes an elongated container body defining an interior cavity with an open end. The vessel further includes a generally cylindrical closure body selectively engageable over the open end of the container body. The closure body includes a lid component and a closure arm. The lid component includes a wall having a dispensing orifice and a vent orifice. Each of these orifices is in fluid-passing communication with the interior cavity of the container body. The closure arm is pivotally connected to the wall of the lid component at a location proximate the vent orifice and is movable between a closed position and an open position. The closure arm includes a first sealing member positioned for engaging the vent orifice when in the closed position and a second sealing member positioned for engaging the dispensing orifice when in the closed position.
In another embodiment, the drinking vessel comprises an elongated container body defining an interior cavity with an open end and a generally cylindrical closure body selectively engageable over the open end of the container body. The closure body includes a lid component and a closure arm, while the container body includes an outer surface. A first portion of the outer surface has a generally circular cross-sectioned cylindrical shape and a second portion of the outer surface has a generally polygonal cross-sectioned cylindrical shape, these first and second portions being longitudinally spaced with respect to each other. The lid component includes a wall having a dispensing orifice and a vent orifice, wherein each orifice is in fluid-passing communication with the interior cavity of the container body. The closure arm is pivotally connected to the wall of the lid component at a location proximate the vent orifice and movable between a closed position and an open position, the closure arm including a first sealing member sized, structured and positioned for engaging and sealing the vent orifice when in the closed position and for unsealing the vent orifice when in the open position, the closure arm including a second sealing member sized, structured and positioned for engaging and sealing the dispensing orifice in the closed position and for opening the dispensing orifice in the open position. This first sealing member further includes an elastomeric member that cooperates with a gasket of the vent orifice to provide a fluid-tight seal when the closure arm is in the closed position.
In a further embodiment, the drinking vessel comprises an elongated container body defining an interior cavity with an open end. Also included is a generally cylindrical closure body selectively engageable over the open end of the container body, the closure body including a lid component and a closure arm. The container body includes an outer surface, a first portion of the outer surface has a generally circular cross-sectioned cylindrical shape and a second portion of the outer surface has a generally polygonal cross-sectioned cylindrical shape, these first and second portions being longitudinally spaced with respect to each other. The lid component includes a wall having a dispensing orifice and a vent orifice, wherein each orifice is in fluid-passing communication with the interior cavity of the container body. The closure arm is pivotally connected to the wall of the lid component at a location proximate the vent orifice and movable between a closed position and an open position, with the closure arm having a first sealing member sized, structured and positioned for engaging and sealing the vent orifice when in the closed position and for unsealing the vent orifice when in the open position. Further, the closure arm includes a second sealing member sized, structured and positioned for engaging and sealing the dispensing orifice in the closed position and for opening the dispensing orifice in the open position, and the first sealing member further includes an elastomeric member that cooperates with a gasket of the vent orifice to provide a fluid-tight seal when the closure arm is in the closed position. The second portion of the outer surface further includes a plurality of spaced protrusions, and the generally polygonal cross-section shape of the second portion of the outer surface is substantially hexagonal.
BRIEF DESCRIPTION OF THE DRAWINGS
In the course of this description, reference will be made to the accompanying drawings, wherein:
FIG. 1 is a perspective view of an embodiment of a drinking vessel of the present invention;
FIG. 2 is a side elevational view of the drinking vessel shown in FIG. 1 ;
FIG. 3 is another side elevational view of the drinking vessel shown in FIG. 1 , rotated 90° with respect to FIG. 2 ;
FIG. 4 is another side elevational view of the drinking vessel shown in FIG. 1 , rotated 90° with respect to FIG. 3 ;
FIG. 5 is another side elevational view of the drinking vessel shown in FIG. 1 , rotated 90° with respect to FIG. 4 ;
FIG. 6 is a top plan view of the drinking vessel shown in FIG. 1 ;
FIG. 7 is a bottom plan view of the drinking vessel shown in FIG. 1 ;
FIG. 8 is a cross-sectional view along the line 8 - 8 of FIG. 1 ;
FIG. 9 is a cross-sectional view along the line 9 - 9 of FIG. 1 ;
FIG. 10 is a cross-sectional view along the line 10 - 10 of FIG. 1 ;
FIG. 11 is an exploded perspective view of the drinking vessel shown in FIG. 1 ;
FIG. 12 is a longitudinal cross-sectional view of FIG. 1 ;
FIG. 13 is a perspective view of an embodiment of a lid of the present invention with the closure arm in the closed state;
FIG. 14 is a perspective view of the lid of FIG. 13 with the closure arm in the open state;
FIG. 15 is a bottom plan view of the lid of FIG. 13 ;
FIG. 16 is an enlarged view of the interaction of the sealing member and venting orifice as shown in FIG. 12 and while in the closed state;
FIG. 17 is a longitudinal cross-sectional view of an embodiment of a lid of the present invention with the closure arm in the open state along with an upper portion of the drinking vessel body; and
FIG. 18 is a longitudinal cross-sectional view of the lid shown in FIG. 17 , along with an upper portion of the drinking vessel body, rotated 90° from FIG. 17 .
DETAILED DESCRIPTION
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention and virtually any appropriate manner.
As described in more detail in the discussion of the different embodiments, the drinking vessels of the present disclosure have an improved structure that generally includes an opening for dispensing the contents from the drinking vessel and has an additional opening for venting air into the drinking vessel. The structure further includes a closure which provides for a fluid-tight seal of both openings and a fluid flow interrupter for mixing beverage contents while within the drinking vessel.
Turning to the embodiment of a drinking vessel illustrated in FIGS. 1-18 , the drinking vessel 10 generally includes a container body 200 and a closure body 300 releasably mounted to the container body 200 . The closure body 300 includes a lid component 302 and a closure arm 304 . The closure arm 304 is movable between a closed position (see FIG. 13 ) wherein the closure arm 304 seals a vent orifice 306 and a dispensing orifice 308 and an open position (see FIG. 14 ) where the closure arm 304 is spaced from or otherwise does not seal the orifices.
In the illustrated embodiment, the container body 200 has a generally elongated shape, preferably generally cylindrical, with a bottom wall 202 and an upstanding side wall 204 which terminates in an open mouth 206 . Together the bottom wall 202 and side wall 204 define an interior cavity 208 (see FIG. 11 ) which is sized and configured for receiving and temporarily storing a beverage, such as water, juices, soft drinks, energy drinks, supplement drinks, or shakes. It will be appreciated that the container body 200 may have any convenient configuration and its form may depend, in part, on the type of container desired.
In order to help a user better grip or otherwise hold the drinking vessel 10 , the outer surface of the container body 200 is ergonomically shaped. As perhaps best illustrated in FIG. 11 , the upstanding side wall 204 of the container body 200 has an outer surface that includes a bottom portion 210 , gripping portion 212 and top portion 214 . The gripping portion 212 includes a plurality of protrusions 216 which extend longitudinally along at least the gripping portion 212 and preferably almost along the entire outer surface. These protrusions 216 are circumferentially spaced from one another around the outer surface of the gripping portion 212 . In the illustrated embodiment, there are six protrusions 216 substantially equally spaced around the outer surface of the gripping portion 212 . However, it will be appreciated that other numbers and spacing of the protrusions 216 are contemplated by the present disclosure.
The outer surface includes landing areas 218 positioned between every neighboring protrusion 216 . In the illustrated embodiment, there are six landing areas 218 , although the number of landing areas 218 can differ depending on the number of protrusions 216 . In order to further affect the shape of the outer surface, additional protrusions 220 are placed on at least some of the landing areas 218 . In the illustrated embodiment, the protrusions 220 are shorter than protrusions 216 and are generally oblong shaped. In the illustrated embodiment, a shorter protrusion 220 is positioned generally centered on four of the six landing areas. It will be appreciated that size, number, shape and placement of the protrusions 220 may be changed, if desired.
The placement of these protrusions 216 and 220 helps define the shape of the outer surface of the container body 200 and more specifically the gripping portion 212 to provide an ergonomical outer surface that allows for better gripping or holding of the drinking vessel 10 . The bottom wall 202 of the container body 200 has a generally circular outer surface (see FIG. 7 ), the placement of protrusions on the outer surface of the side wall changes the cross sectional configuration moving up the outer surface. As shown in FIG. 8 (a cross-sectional view along the line 8 - 8 of FIG. 1 ), the outer surface of the side wall 204 towards the bottom of the gripping portion 212 has a generally polygonal shape and more specifically, a generally hexagonal shape. Moving up the side wall 204 , the hexagonal shape of the outer surface of the gripping portion 212 is altered with the addition of the shorter protrusions on four of the landing areas 218 which are the faces of the hexagon (see FIG. 9 , a cross-sectional view along the line 9 - 9 of FIG. 1 ). Continuing to move up the side wall at an area outside of the gripping portion 212 , the outer surface of the side wall 204 returns to a generally circular shape (see especially FIG. 10 , a cross-sectional view along the line 10 - 10 of FIG. 1 ).
The container body 200 is typically constructed from a high strength, lightweight material such as conventional polymers or metals suitable for containing food and beverage products. In the illustrated embodiment, the container body 200 is constructed of stainless steel and the protrusions 216 and 220 are stamped into the steel (see FIG. 12 ). However, it is understood by those skilled in the art that the shape and material used to construct the container body and protrusion can be modified without departing from the spirit and scope of the invention. For example, the protrusions can be separately formed of a different material and attached to the outer surface.
As mentioned above, the open mouth 206 of the container body 200 is closed by the closure body 300 which generally includes a lid component 302 and a closure arm 304 . The lid component 302 and closure arm 304 are typically molded and more specifically injection molded, out of conventional polymers such as polypropelenes. However, it will be appreciated that the invention is not limited to these materials and that any suitable material may be used.
As best shown in FIGS. 6 and 11 - 15 , the lid component 302 preferably is generally circular in order engage the top portion of the container body. The lid component 302 has a flange 310 which extends downward from a top surface 312 . In the illustrated embodiment, the top surface 312 is generally sloped; however, it will be appreciated that the top surface 312 may have a variety of configurations including being generally flat, convex or concave.
In the illustrated embodiment, the lid component 302 further includes a skirt 314 which has a circumferential recess 316 defined on the top surface 312 . The recess 316 is sized to tightly receive an end portion of flange 310 . A gasket 318 may be positioned within recess 316 in order to render a fluid-tight seal between flange 310 and skirt 314 . Alternatively, the skirt and flange could be integrally formed. Optionally, a decorative element 320 may be positioned around at least a portion of flange 310 . In the illustrated embodiment, the decorative element 320 is a stainless steel ring. It is appreciated that the decorative element 320 could be constructed of different materials or may also serve as a surface for the imprinting of trademark, advertising or graphical materials for the purposes of branding, advertising or promotion. However, it also will be understood by those skilled in the art that the shape and material used to construct the lid component 302 can be modified without departing from the spirit and scope of the invention. For example, the lid component 302 can be virtually in the form of any shape that is capable of covering the open mouth 206 of the container body 200 .
As mentioned above, the container body 200 is selectively secured to the closure body 300 . In the illustrated embodiment, the top portion 214 of the container body 200 includes threads 222 for selectively engaging corresponding grooves 322 on an interior surface of the lid component 302 of the closure body 300 . Accordingly, the container body 200 and closure body 300 may thus be selectively threadedly engaged or disengaged as desired. When the components are engaged the interior cavity 208 is formed into a closed, fluid-tight cavity.
As perhaps best illustrated in FIG. 12 , grooves 322 are formed on the lid component 302 and more specifically an interior surface of skirt 314 of the lid component 302 . Although it will be appreciated that the grooves 322 could be located elsewhere on the lid component 302 , if desired. Alternatively, one could swap the location of the threads and grooves such that the threads 222 are defined on the lid component 302 and the grooves 322 are defined on the container body 200 . In addition, it will be appreciated that the closure body 300 could be selectively secured to the container body 200 via a variety of other mechanisms without departing from the spirit and scope of the invention. For example, the lid component 302 could be snap fit or friction fit to the container body 200 without the use of threads.
In order to allow the beverage to be selectively dispensed from the drinking vessel 10 and to allow the flow air into the interior cavity 208 of the container body 200 during use, the lid component 302 defines a dispensing orifice 308 and a vent orifice 306 on the top surface 312 . Both of these orifices 306 and 308 are passageways which extend completely through the top Surface 312 . In the illustrated embodiment, the vent orifice 306 is a bore which is positioned within a depression 324 on the top surface 312 . The depression 324 is sized to receive at least an end portion of the closure arm 304 and allow the closure arm 304 to be pivoted without interference with the top surface 312 . As shown in the drawings, the dispensing orifice 308 is surrounded by a raised annular spout 326 which allows a user to more easily drink the contents of the drinking vessel 10 .
In order to allow the user to selectively dispense the contents from the drinking vessel, the closure body 300 includes an elongated closure arm 304 that is pivotally mounted to the lid component 302 . In the illustrated embodiment a hinge configuration allows the closure arm 304 to be pivoted by the user between a closed position (see FIG. 13 ) and an open position (see FIG. 14 ). When the closure arm 304 is in the open position, the orifices 306 and 308 are generally unobstructed and when the closure arm 304 is in the closed position, the orifices 306 and 308 are sealed in order to prevent the contents from flowing out of the interior cavity 208 of the drinking vessel 10 .
It will be appreciated that any variety of hinge configurations could be used; however, in the embodiment shown in FIG. 18 , the hinge is formed by the cooperating interaction of pivot pins 328 and sockets 330 . A pivot pin 328 is formed on opposing sides of one end of the closure arm 304 . Each pivot pin 328 is seated within a socket 330 formed on the lid component 302 . In the illustrated embodiment, a socket 330 is formed on an interior wall of a pair of spaced apart upstanding shoulders 332 positioned on the top surface 312 of the lid component 302 . More specifically, the shoulders 332 bracket the depression 324 which includes the vent orifice 306 positioned therewithin. As perhaps best shown in FIG. 17 , when the closure arm 204 is pivoted to its open position, the end of the closure arm 204 that is hinged to the lid component 302 rotates in such a way that the vent orifice is not completely obstructed and air can flow around the closure arm 204 , into the depression 324 in the lid component 302 , through the vent orifice 306 and ultimately into the interior cavity 208 of the drinking vessel 10 . As illustrated, when in the open position, the closure aim 204 acts as a shield to substantially prevent debris from entering contaminating the contents of the interior cavity 208 of the drinking vessel.
It will be appreciated that the shoulders 332 may be integrally formed with the lid component 302 or alternatively separately secured to the top surface by any conventional assembly techniques known in the art. Alternatively, the location of the pins 328 and sockets 330 could be interchanged such that the pins 328 are formed on the shoulders 332 and the sockets 330 are formed on the closure arm 304 . Further, one skilled in the art will appreciate a variety of other configurations that allow the closure arm to pivot between the open and closed positions may be used without departing from the spirit and scope of the invention. For example, the closure arm may be integrally constructed with the lid component and form a “living” hinge.
In order to help the user more readily grasp and move the closure arm 304 between the open and closed positions, at least one tab 334 may be formed on the closure arm. In the illustrated embodiment, the tab 334 is located at the free end of the closure arm 304 and is sized and configured for grasping by the user. It will be appreciated that the tab 334 may be positioned elsewhere on the closure arm 304 or have other configurations than illustrated.
The closure arm 304 includes at least two sealing members which are used to create a fluid-tight seal with the vent and dispensing orifices. The first sealing member 336 interacts with the vent orifice 306 and the second sealing member 338 interacts with the dispensing orifice 308 . The sealing members 336 and 338 are positioned on the closure arm 304 such that each member engages its respective orifice when the closure arm 304 is in the closed position. When engaged, each sealing member and its respective orifice cooperate to seal and otherwise prevent the contents from unintentionally spilling or leaking out of the drinking vessel 10 .
In the illustrated embodiment, the first sealing member 336 includes projection or plug which extends from a bottom surface of the closure arm 304 . The projection is positioned such that when the closure arm 304 is in the closed position the first sealing member 336 cooperatively engages with the vent orifice 306 to prevent fluid flow therethrough. Preferably, the first sealing member 336 further includes an elastic seal member 340 , such as an elastomer, that covers at least an end of the projection. In the embodiment illustrated in FIG. 16 , the seal member 340 has one or more fingers which fit into one or more slots in the projection on the closure aim 304 . Alternatively, the seal member 340 could be overmolded or otherwise attached to the projection.
A gasket 342 surrounds the vent orifice 306 on the top surface of the lid component 302 to help form a fluid-tight seal between the first sealing member 336 and vent orifice 306 . When the closure arm 304 is in the closed position, the gasket 342 cooperatively interacts with first sealing member and more specifically the seal member 340 on the end of the projection. In the illustrated embodiment, the gasket 342 is an elastomer that is overmolded into a channel 343 formed on the bottom surface of the lid component 302 . The gasket 342 has a disc shaped end that creates a rim around the vent orifice 306 . Preferably, the gasket 342 is a thermoplastic elastomer; however, it is appreciated that other materials may be used. Examples include Trefsan™ elastomers and Proflex® thermoplastic elastomers, such as Proflex GE-S Series elastomers. Included are compositions of styrenic block copolymers, including blends thereof with polypropylene and/or processing oil and other conventional additives.
In the embodiment illustrated in FIG. 14 , the second sealing member 338 is a well or receptacle defined in the second end portion of the closure arm 304 . The well is sized to sealingly receive or engage the annular spout 326 of the dispensing orifice 308 when the closure arm 304 is in the closed position. It is to be understood that the first and second sealing members may have other suitable configurations. For example, the second sealing member 338 could also be or include a plug formation that extends into and tightly engages the annular spout 326 when the closure arm 304 is in the closed position.
It will be appreciated that elastomeric surfaces or components can be provided to enhance sealing at either or both of the vent or dispersing passageway components. Elastomeric surfaces or components can be provided on either or both of the closure arm side or the lid component side.
The drinking vessel 10 may further include a fluid flow interrupter 344 positioned within the interior cavity 208 for agitating, stirring or mixing of the contents of the drinking vessel. In the illustrated embodiment, the fluid flow interrupter 344 is connected to the skirt 314 of the lid component 302 . More specifically, the interrupter 344 in the embodiment shown in the figures includes multiple spokes which extend or slope generally downward into the interior cavity 208 from an inner flange of the skirt 314 . The spokes are spaced apart from one another enough to allow fluid to flow relatively easily therethrough but also to provide enough disturbance to the fluid. The spokes are connected to one another via a central hub. As shown, the interrupter 344 is constructed of a plastic material such as polypropylene; however, it is appreciated that a variety of other suitable materials may be used. It will also be understood by those skilled in the art that there are a variety of other suitable ways and forms to include fluid flow interrupters in the drinking vessel without departing from the spirit and scope of the invention. For example, the interrupter may be a separate piece that is inserted into the interior cavity. Also the interrupter can be stationary or moveable.
In operation, a user may insert the desired beverage through the open mouth 206 and into the interior cavity 208 of the container body 200 . The user may selectively secure the closure body 300 to the top portion 214 of the container body 200 . With the closure arm 304 in the closed position, a user may manually or otherwise shake the drinking vessel to create a disturbance of the beverage within the drinking vessel 10 . When the user desires to drink the beverage, the user may pivot the closure aim 304 to the open position to unseal the dispensing orifice 308 and venting orifice 306 . In this position, the beverage can be selectively dispensed from the dispensing orifice 308 and air can enter through the venting orifice 306 into the interior cavity 208 of container body 200 to allow the beverage to be dispensed out of the drinking vessel 10 more rapidly and with less exertion by the user. When the user no longer wants to dispense the beverage, the closure arm 204 can be pivoted back to the closed position such that each sealing member engages its respective orifice and create a fluid-tight seal.
It will be understood that the above examples are merely exemplary of the drinking vessel and valve arrangement of the present disclosure. Variations of these examples may become apparent to those of ordinary skill in the art upon reading the foregoing description. It will be appreciated that skilled artisans may employ such variations as desired, and drinking vessels and valves of the present disclosure may be constructed otherwise than as specifically described herein. Accordingly, all modifications and equivalents of the subject matter described herein are intended to be covered by the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements and all possible variations thereof are encompassed by the present disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.
|
Drinking vessels have an elongated container body joined with a closure body having a dispensing orifice and a vent orifice, each in fluid-passing communication with the interior of the container body. A closure arm is rotatably mounted near one end of it and has at least two sealing members spaced from each other along the length of the closure arm, one of the sealing members opening and closing the vent opening while another of the sealing members opens and closes the vent opening while another of the sealing members opens and closes the dispensing orifice when the closure arm is rotated between its open and closed positions. At least the sealing member for the vent orifice has an elastomeric surface that sealingly engages a surface at the vent orifice when at the closed position. Elastic surfaces can instead or in addition be provided at the vent orifice surface or one or both opposing surfaces of the dispensing area.
| 1
|
BACKGROUND OF THE INVENTION
1. Technical Field
The invention relates broadly to semiconductor device fabrication and, more particularly, to techniques for controlling inventory of monitor wafers in an automated semiconductor factory (FAB).
2. Related Art
The following comments are adapted from an article entitled “Tracking the performance of photolithographic processes with excursion monitoring”, by Eric H. Bokclberg and Michael E. Pariseau, IBM Microelectronics.
In today's high-volume semiconductor fabs, photolithographic process steps (wafer prime, resist-apply, expose, bake, and develop) are performed in sequence hundreds of times on hundreds of wafers per day to produce well-defined photoresist patterns. In many cases, these litho process steps are combined into one tool, referred to as a photocluster, that links a resist-process track system with an exposure tool. Because lithography plays a critical role in creating device features throughout the semiconductor production operation, accurate, repeatable photocluster performance is vital, and the individual tools are typically monitored by means of numerous tool checks (inspection procedures designed to evaluate specific components of the process). Examples include resist-film-thickness and hot-plate temperature uniformity measurements on the track, and dose-uniformity and focus-control evaluations on the expose tool. Assessment of defect performance is limited to foreign material (FM) particulate inspections through subprocesses such as resist-apply, develop only, or dry-wafer handling. While the individual tool checks ensure that many of the most critical components of the litho process are within established specifications, they are unable to monitor the interactions between components, which can create out-of-spec conditions in the printed pattern even though individual tools are in spec. Consequently, the integrated litho process is also monitored through inspections and measurements of production wafers. In-line product parametric data are sorted by photocluster and displayed in tool-specific statistical process control (SPC) charts. When out-of-control trends are identified, operation of the problem tools is inhibited until the problem can be investigated and resolved.
As long as these inspections occur immediately after the litho process, and the products and levels processed on each tool are consistent from day to day (as in a large-volume, single-part-number fab), this approach to photo tool control works reasonably well. However, as fab product loading becomes more varied, with multiple part numbers and multiple levels being processed on each photo tool, trend identification becomes more difficult and individual photo tool excursions are not always immediately evident. Furthermore, when defect inspection is 1 or 2 days downstream of the photo operation and 3 days worth of data are needed to recognize a trend, thousands of wafers can be affected by a tool problem before it becomes apparent.
Detection of a tool problem in the back end of the line (BEOL) may take even longer because prior-level “noise” can obscure defects during in-line inspection, and photo process excursions may not be evident until electrical testing several weeks later. The time delays between when excursions occur and when they are actually detected are critical factors in maintaining wafer yields and device performance—for each day that a defect or dimensional problem remains undetected, hundreds of wafers can be affected.
One solution to this problem is to track each tool's defect and dimensional performance daily with an excursion monitor-a clean wafer that is processed with a unique resist pattern and then inspected for defects and critical dimensions. Because there are no influences from prior levels, the data plots for each monitor can clearly reveal problems that existed too briefly to be identified by in-line product measurements.
This article outlines the challenges faced in establishing a daily excursion monitor program and presents examples of process excursions that have been successfully identified.
The excursion monitor program that has been adopted by the IBM Microelectronics Division in Essex Junction, Vt., is a daily tool check that identifies photo-process equipment malfunctions and other process excursions as soon as they occur, minimizing product rework, scrap, and yield loss. The concept is simple: a clean wafer is fully processed through a photocluster to create a specially designed resist pattern. The monitor wafer is then inspected, defects are classified, and the resist critical dimension (CD) is measured using scanning electron microscopy (SEM). Defect and measurement data are plotted in tool-specific SPC charts to monitor each tool's performance and identify trends. Because the excursion monitor is intended to be processed, inspected, and measured in the same way that production wafers are, it has been designed for ease of manufacturability with simple, straightforward patterning that can be integrated within a normal sequence of production lots at any operation.
FIG. 1 is a diagram illustrating the excursion monitor process flow. Reclaimed wafers to be used as excursion monitors are initially inspected for FM. They are then delivered to the photocluster, where they are coated with resist and developed using a standard production resist process, except that they are exposed using a reticle specifically designed for excursion monitoring.
The aforementioned article describes the process flow of the wafer as it pertains to the use in the FAB and at the process tools.
The present invention deals with the wafer prior to entering the FAB for processing and after the wafers are selected for reclaim (last step, upper left, in FIG. 1 )—namely, pre and post processing in the FAB.
A common problem with releasing monitor wafers into the FAB is staying within budget. There is also a problem with consistency in controlling the wafers while released in the FAB (releasing and getting the wafers off the floor). (“Controlling” a wafer is the process of releasing the correct part numbers to the FAB, reusing returned wafers in different process areas to reduce cost, and finally reclaiming wafers to an outside vendor. “Releasing” is the process of taking a raw wafer, placing it into a FOUP (Front Opening Universal Pod), and assigning to a wafer route so it can be used in the FAB.)
SUMMARY OF THE INVENTION
The problem being solved is controlling stocker capacity in an automated facility and controlling monitor budgets by capped releases, capped FOUP supplies, and wafer reuse methodology.
It is an object of the invention to tightly control the release of monitor wafer when at the same time controlling stocker supply in an automated factory.
Generally, the invention advantageously utilizes a Lotus Notes Database to order, track, and reclaim test (monitor) wafers in the FAB. (Any type of database having saving and manipulating files functionality could be used to implement this process.) This database automatically controls the amount of FOUPs in the FAB as well as the amount of wafers released into the FAB each day. This database also interacts with the Control Center in helping to release monitor wafers in the FAB.
“Reclaiming” is the act of taking the wafers out of service (after they are no longer needed) and sending to an outside vendor to be reworked for future use.
According to the invention, a method of controlling an inventory of monitor wafers in an automated semiconductor factory (FAB) comprises the steps of:
submitting a monitor wafer buy request by a process area (PA);
determining whether the PA is under budget;
if the PA is not under budget, canceling the transaction;
if the PA is under budget, determining the monitor wafer by the database (DF), and
releasing the request with either prime wafers, reclaimed wafers or reused wafers, as determined by the database (DF),
after the monitor wafers are used in the process areas (PA), returning the wafers to the control center (CC);
after returning the monitor wafers to the control center (CC), determining whether or not the monitor wafers can be reused.
According to the invention, a computerized method of controlling inventory of monitor wafers in an automated semiconductor factory (FAB) comprises providing a system having at least one computer, and on the at least one computer performing the following steps of manipulating and displaying files:
displaying a view of MPC (Manufacturing Process Center) On Demand where technicians can view all the monitor wafers that need attention and where the technicians can program the database; displaying a view of Control Center on Demand where Budget Control Files and stocker Control Files are displayed; displaying a view of Budget Control Files which is the file that controls the amount of wafer monitors that a process area (PA) can purchase in a set period of time; and displaying a view of Stocker Control File which is the file that controls the amount of Front Opening Universal Pods (FOUPs) that a process area can have in the FAB.
According to the invention, an article of manufacture comprises a computer usable medium having computer readable program code means embodied therein for controlling inventory of monitor wafers in an automated semiconductor factory, the computer readable program code means in said article of manufacture comprising computer readable program code means for causing a computer to effect the steps of the computerized method mentioned above.
BRIEF DESCRIPTIONS OF THE DRAWINGS
The structure, operation, and advantages of the present invention will become further apparent upon consideration of the following description taken in conjunction with the accompanying figures (FIGS.). The figures are intended to be illustrative, not limiting.
FIG. 1 is a flowchart illustrating an exemplary excursion monitor process flow of the prior art.
FIG. 2 is a flowchart illustrating an embodiment of the operation of the Semiconductor Factory—Monitor Wafer Purchase and Controls Database of the present invention.
FIG. 3 is a diagram of a system having multiple networked computers for implementing the invention.
FIGS. 4–9 are drawings of screenshots, such as would be viewed (on computer monitors) by users of the system ( FIG. 3 ) implementing the invention, according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
In the description that follows, numerous details are set forth in order to provide a thorough understanding of the present invention. It will be appreciated by those skilled in the art that variations of these specific details are possible while still achieving the results of the present invention.
The invention provides a technique for tightly controlling the release of monitor wafer while at the same time controlling stocker supply in an automated factory.
FIG. 2 is a flowchart illustrating an embodiment 200 of the operation of the Semiconductor Factory—Monitor Wafer Purchase and Controls Database of the present invention. Various steps are shown, in three categories:
Process Areas (PA)
Control Center (CC)
Database Function (DF)
In a first step 202 a monitor (referred to herein as monitor wafer or wafer) buy request is submitted by a process area (“PA”). Next, in a step 204 , it is determined whether the process area is under budget and, if not (i.e., the PA is over budget) the transaction is cancelled in a step 206 (this is a database function “DF”). See also FIGS. 5 , 6 , 7 .
If the PA is under budget (“yes” result in 204 ), in a step 208 the monitor type is determined by the database. And, the request is released with either prime wafers (step 210 ), reclaimed wafers (step 212 ) or reused wafers (step 214 ), as determined by the control center (“CC”).
In a next step 216 , the monitor wafers are being used in the process areas. See also FIGS. 8 and 9 .
Then, after being used, the monitor wafers are returned to Manufacturing Processing Center (MPC). And in a step 218 , monitors wafers are selected for reclaim when they have reached the end of their useful life. See also FIG. 9 .
Next, in a step 220 , it is determined whether the wafers can be reused. If not, they are sent for reclaim, step 222 (this is a control center (CC) function). If so (“yes” result of step 220 ), in a step 224 , the wafers are assigned to a reuse group (this is a database function (DF)).
Next, in a step 226 , the returned monitor wafers are reviewed by an MPC technician, and they are either sent for reclaim (step 228 ), sent for cleaning (step 230 ), or placed in reuse substock for future use (step 232 ). Wafers which are cleaned (step 230 ) also make it to the reuse substock for subsequent use (step 232 ) via a step 234 (Reclaim Group Assignments).
As shown in the flowchart, monitor wafers which have been placed in the reuse substock for future use make their way back into the system at step 208 as “reused” wafers. As shown by the step 222 , 228 wafers which have been sent for reclaimed are effectively removed from the system.
The invention is suitably implemented as a software program running on one or more computers, in one or more physical locations. FIG. 3 is a very generalized illustration of a system 300 one computer 310 (having a keyboard 312 , a mouse 314 and a monitor 316 ) upon which the program and relevant files are resident, and at least one other computer 320 (having a keyboard 322 , a mouse 324 and a monitor 326 ) connected in communication with the first computer via a wired or wireless network 330 . One of ordinary skill in the art to which the present invention most nearly pertains will readily understand how to implement the invention, as described both hereinabove and hereinbelow, based on the functional descriptions and examples set forth herein. For example, the software program can be implemented using Microsoft Windows operating system, and a graphical user interface (GUI) that many of us are well-accustomed to. The computer implementation is all rather straightforward and conventional, and requires no further description.
FIGS. 4–9 are representations of screenshots, such as would be displayed on computer monitors ( 316 , 326 ) by users of the system implementing the invention, as described above.
FIG. 4 is a screenshot showing a view of MPC On Demand, according to the invention. This is where technicians can view all the monitors that need attention and where they can program the database. Generally, there is a main window 400 having seven individual, smaller windows 401 – 407 , each of which displays a list to a user.
A first window 401 displays a MPC Substock Queue which is where reuse monitor wafers available to be released are listed. A technician can review the available wafers.
A second window 402 displays a “MPC Tech Attention Queue” which is where returned monitor wafers waiting to be reviewed by a tech (technician) are listed. The technician can set parameters as to where they are sent.
A third window 403 displays a “MPC in Clean Queue” which is where monitor wafers that are good but require cleaning are listed.
Windows 404 through 407 contain control files.
The fourth window 404 displays “Reuse Routes” which is where monitor routes identified to release as reuse wafers are listed. The technician can set parameters to grade the wafers.
A fifth window 405 displays “Reclaim Routes” which is where wafer monitor routes identified to release as reclaim wafers are listed.
A sixth window 406 displays “Incoming Group Associations” which is where monitor routes identified to reuse groups are listed. The technician can program the group associations so that all of the wafers are in specific groups for particular uses.
A seventh window 407 displays “Bypass Tech Review” which is monitor routes identified to automatically reclaim are listed. The technician can program the group associations so that bad wafers never reach the “Reuse Routes” shown in the fourth window 404 .
FIG. 5 is a screenshot showing a view of Control Center on Demand, according to the invention.
Generally, there is a main window 500 , smaller window 501 and a smaller window 502 . In window 501 , the technician can program the budget for the manufacturing area and display the “Budget Control Files”. In window 502 , the technician can control the number of FOUPs which hold the wafers and the number of stockers which hold the FOUPs are allowed in the process area.
FIG. 6 is a screenshot showing a view of Budget Control File, according to the invention. This is the file that controls the amount of wafer monitors that a process area (PA) can purchase in a set period of time, e.g., week. Wafer monitors cannot be ordered if the budget is exceeded unless a waiver is submitted (see FIG. 8 ). Generally, there is a main window 600 , and a three areas 601 – 603 within the window.
A first area 601 displays a list of current wafer monitor releases for a period of time, such as a week. This provides a reporting tool.
A second area 602 displays type of wafer monitor released and where they are located. This provides a reporting tool.
A third area 603 displays wafer monitor budgets, by process sector or area. The technician is able to make adjustments or set the budgets for the number of wafer monitors used in each area.
FIG. 7 is a screenshot showing a view of Stocker Control File, according to the invention. This is the file that controls the amount of FOUPs that a process area can have in the FAB. Monitor orders are not permitted (are prohibited) if their FOUP supply exceeds their budget. Generally, there is a main window 700 , and a list 701 of stocker budgets by process area. Here the control center (CC) manager can adjust the stocker budgets by clicking at 702 .
FIG. 8 is a screenshot showing a view of Budget Increase Waiver form, according to the invention. This is where production managers can increase their budget if extra wafer monitors are needed, such as for unplanned maintenance. (refer to the “waiver” mentioned in the description of FIG. 6 ). Generally, there is a main window 800 , and a number of GUI items 801 – 807 . Here is where production managers or technicians can increase their budget if extra wafer monitors are needed, such as for unplanned maintenance.
The production manager clicks on the button 801 to start the change order, and enters his name.
The production manager clicks on the button 802 to enter a reason for the budget change.
The production manager clicks on the button 803 to test the increase (or decrease) in the budget change.
The production manager clicks on the button 804 to select the project for which a budget change is being submitted.
The production manager clicks on the button 805 to enter the amount of monitor wafers by which the budget will be increased.
The production manager clicks on the button 806 to submit the budget adjustment.
The production manager clicks on the button 807 to exit the form.
FIG. 9 is a screenshot showing a view of Process Area Monitor Inventory, according to the invention. This is where users make their wafer buy request, and is used to buy additional wafers to add to inventory. Here can be seen the wafer monitor inventory available for process area (PA) to use. Generally, there is a main window 900 , including the following functions:
a button 901 for entering a wafer buy request which is used to buy additional wafers to add to inventory;
a button 902 for viewing the weekly wafer monitor budget; and
a button 903 for viewing the target number of FOUPs versus the actual number of FOUPs.
The present invention can be realized in a centralized fashion in one computer system, or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system—or other apparatus adapted for carrying out the methods described herein—is suitable. A typical combination of hardware and software could be a general purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein. The present invention can also be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which—when loaded in a computer system—is able to carry out these methods.
Computer program means or computer program in the present context mean any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after conversion to another language, code or notation and/or reproduction in a different material form.
It is noted that the foregoing has outlined some of the more pertinent objects and embodiments of the present invention. This invention may be used for many applications. Thus, although the description is made for particular arrangements and methods, the intent and concept of the invention is suitable and applicable to other arrangements and applications. It will be clear to those skilled in the art that other modifications to the disclosed embodiments can be effected without departing from the spirit and scope of the invention. The described embodiments ought to be construed to be merely illustrative of some of the more prominent features and applications of the invention. Other beneficial results can be realized by applying the disclosed invention in a different manner or modifying the invention in ways known to those familiar with the art.
Although the invention has been shown and described with respect to a certain preferred embodiment or embodiments, certain 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 components (assemblies, devices, circuits, etc.) the terms (including a reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiments of the invention. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several embodiments, such feature may be combined with one or more features of the other embodiments as may be desired and advantageous for any given or particular application.
|
Controlling stocker capacity in an automated facility and controlling monitor budgets by capped releases, capped FOUP supplies, and wafer reuse methodology. A Database is used to order, track, and reclaim test (monitor) wafers in the FAB. The database automatically controls the amount of FOUPs in the FAB as well as the amount of wafers released into the FAB each day. This database also interacts with the Control Center in helping to release monitor wafers in the FAB.
| 8
|
This application claims the benefit of Provisional application Ser. No. 60/074,976 filed Feb. 17, 1998.
TECHNICAL FIELD
The present invention relates in general to wireless communication systems and in particular to a code division multiple access (CDMA) protocol named Slotted Aloha for transmitting packets of data between a mobile subscriber or station (MS) and a base station (BS) over an access channel slot comprising a preamble portion and a message capsule portion.
BACKGROUND
In prior art CDMA wireless systems, a mobile station (MS) would access a base station (BS) using a protocol named slotted Aloha.
When a MS is turned ON, it synchronizes itself to receive forward link (FL) transmissions from the BS as part of an initialization process. This synchronization is maintained as the MS moves about the cell generated by transmissions from the BS. Because this synchronization is maintained, the BS may send data to any specific MS or to all MSs in the vicinity of the BS in accordance with standardized protocols. This synchronization process is not applicable to transmissions over the reverse link (RL) from a MS to a BS.
An MS may contact or access a BS to register when entering a system foreign to its registered home system or to originate a service like a voice call and so forth. Thus CDMA wireless systems provide for allowing an MS to access the BS over an access channel during any one of consecutive time periods defined as access channel slots in accordance with the previously referred slotted Aloha protocol. If an MS is not making an outgoing call, it may remain in an ON condition all day and never use the access channel.
To perform the access function, the mobile sends an access probe comprising one time slot including a preamble time portion and a message capsule time portion. During a portion of the preamble time, the base station searches for a mobile station transmission. This portion is called the search window. If a mobile station transmission is detected by the BS, then the BS will try and synchronize to the mobile station's transmission during the preamble time.
After the preamble portion of the time slot is completed, the base station will decode the message capsule.
The slotted Aloha protocol is known as a random access protocol which may experience collisions due to more than one mobile station attempting to access the base station during the same time slot. This condition may be alleviated by designing the hardware to accommodate more than one mobile station per slot. Such action or designing is outside the scope of this invention.
In the slotted Aloha protocol, implemented in current CDMA mobile phone systems, of the prior art, the preamble consists of a multiple of 20 millisecond frames. The message capsule also consists of a plurality of 20 millisecond frames. The number of 20 millisecond frames in each of the preamble and the message capsule portions of the time slot may be adjusted on a base station by base station basis throughout the wireless system in accordance with the radio environment for each base station. In other words, certain poor quality radio environments or environments where the base station covers a large area may require a longer preamble than base stations having a smaller area or better radio environment. Further, it may be that mobile station subscribers located in the area of some base stations typically transmit longer messages than occurs at other base stations. In such a situation, it may be more expedient to have more frames in the message capsule portion of the access channel slot for those base stations than for other base stations typically having shorter messages. The efficiency of this protocol is bounded by equation 1 where M is the number of message capsule frames and P is the number of preamble frames.
M*0.02/(P*0.02+M*0.02) (1)
In other words, if, as an example, there were 5 message frames and it took more than 2 preamble frames but less than 3 preamble frames to assure synchronization at any site within the cell defined by a given BS, the maximum efficiency would be (5*0.02)/(3*0.02+5*0.02) or 62.5%.
If the worst case time to assure synchronization with respect to a given BS for the example outlined above happens to be 2.1 frames, then {fraction (9/10)}ths of the preamble time frame is “wasted” each access period.
Thus far, this discussion has identified inefficiencies due to the preamble frame duration. In addition to the preamble frame duration, the frame time duration of the message capsule will also impact the overall protocol efficiency. However, there are additional constraints. For example, the message capsule frames also contain overhead bits, where usually the number of overhead bits remains constant independent of the frame duration. Thus, a decrease in the frame time for the message capsule, without proper adjustments (e.g., like increasing the message capsule data rate), could cause the overall protocol efficiency to decrease.
It would thus be desirable to provide a method whereby the time required to obtain preamble synchronization (i.e., a multiple of the preamble frame duration) is not required to be identical to the message capsule frame duration and in the most general case not required to be a frame time related multiple or sub-multiple of the message capsule frame time.
SUMMARY OF THE INVENTION
The present invention comprises the method of increasing the efficiency of data transmission, between a mobile subscriber or station (MS) and a base station (BS), by altering the frame size (time slot length) of at least one of the access channel preamble and the access channel message capsule from that standardized in the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, and its advantages, reference will now be made in the following Detailed Description to the accompanying drawings, in which:
FIG. 1 is a block diagram of a cellular system for use in explaining the operation of the invention;
FIG. 2 is a representation of an access channel time slot as practiced in the prior art slotted Aloha protocol; and
FIG. 3 is a representation of an access channel time slot as practiced in the present invention
DETAILED DESCRIPTION
In FIG. 1 a cellular network is represented by a block 10 and is connected via a communication connection 12 to a base transmission station (BTS) 14 . An area 16 around the BTS 14 defines a cell within which are located several mobile stations. One station 18 is located near the edge of cell 16 while a second mobile station 20 is located adjacent BTS 14 . A third mobile station 22 is located intermediate the distance from BTS 14 to the edge of cell 16 .
In FIG. 2 a vertical line 30 defines a demarcation between a previous access channel slot and an access channel slot shown in detail. A second vertical line 32 delineates between the detailed access channel slot and a subsequent access channel slot. As indicated, the time between lines 30 and 32 represents the time completed during one access channel slot. Between lines 30 and 32 , a third line designated as 34 divides the access channel slot into an access channel preamble (left-hand side) and an access channel message capsule (right-hand side). A horizontal line 36 , extending from lines 30 to 32 is intersected by a plurality of indicia. On the left-hand side several indicia, 38 , 40 , 42 and 44 are numerically designated. Between lines 34 and 32 , several additional indicia 46 , 48 , and 50 are also designated. After each of the indicia 44 and 50 , a symbol is used to show a break in the number of indicia. As indicated in the preamble portion, each of the indicia represent one frame of information and the prior art standards set forth by IS-95 stated that each of the frames would last 20 milliseconds. The preamble may be set at any number of frames from one to 16 in accordance with the radio conditions determined to be in a given cell. The prior art provided for a range of three to 10 message frames in accordance with traffic conditions in a cell. Thus the standard provided for a flexibility of each access time between channel slots (vertical lines 30 and 32 ) ranging from four to 26 frames for a given BTS.
In FIG. 3 a first vertical line 60 provides a demarcation between a previous access channel slot and an access channel slot shown in detail. A further vertical line 62 provides an indication of the end of the access channel slot shown in detail and a subsequent access channel slot. A vertical line 64 shows the demarcation between the preamble portion of the channel slot and the message capsule portion of the channel slot. A plurality of equally spaced indicia are shown on the preamble side with two of the indicia labeled as 66 and 68 . On the message side a further plurality of indicia are illustrated. These indicia are equally spaced but are spaced differently than those on the preamble side. Two of the indicia are in the message side are indicated as 70 and 72 . As an example, the indicia 66 and 68 may represent a preamble frame of the 1.25 milliseconds or alternatively could represent a frame having a time duration of five milliseconds. A message frame such as indicated by an indicia 70 and 72 would typically last a longer time than would preamble frames. Thus, for example, the time represented by message frame indicia 70 and 72 might be either 10 milliseconds or 20 milliseconds. In further explanations the preamble frame time will be represented by T 1 and the message frame time will be represented by T 2 .
While not shown in either of FIGS. 2 and 3, for the purpose of lessening the probability of collisions, it should be noted that the IS-95 standard for the telecommunications industry allows for a randomization delay between the left-hand side of an access channel slot and the actual access probe transmission from the mobile station.
As is known in the industry, as an MS moves around a cell, the radio environment may change so that at different locations, more or less time is required for a BTS to synchronize with the preamble signal than it did at another location in the cell. In setting up a cellular system, many conditions are checked to determine the maximum time required for a BTS in a given cell to synchronize to a preamble signal in an access channel slot. As discussed in the background section, if it requires slightly more than two 20 ms frames (more than 40 ms) for the BTS to achieve synchronization under worst case conditions, 60 ms would be used under the prior art protocol set forth in conjunction with FIG. 2 . If a frame extending over a shorter time period such as 1.25 ms were used as set forth in FIG. 3, the synchronization time required for the preamble could more nearly be optimized. Furthermore, as will be discussed later, since a given number of bits of overhead data are required in each message capsule frame, smaller message capsule frames, without a corresponding change (increase) in data rate, would typically reduce message transfer efficiency.
Reference will now be made to FIG. 3, wherein it will be assumed that the preamble frames are chosen to be 1.25 ms in length and the time T 2 for the message frames are chosen to be 20 ms. If the worst case condition for synchronization is 21 ms, 17 preamble frames will suffice for the preamble portion of the access channel slot. If equation 1 is used and 1.25 ms substituted for the preamble frame time, equation 2 below will be obtained and it will be determined that the protocol efficiency is now (5*0.02)/(17*0.00125+5*0.02) or 0.1/(0.02125+0.1), in general given by
M*0.02/(P*0.00125+M*0.02). (2)
This computation equals 82.47% potential efficiency as compared to the previously obtained value of 62.5% when the preamble frame was required to be the same time duration as the message capsule frame.
M*T 2 /(P*T 1 +M*T 2 ) (3)
The efficiency bounds of the present inventive protocol may thus be expressed in the general terms of equation 3 where M and P are as previously defined and T 1 is representative of the time duration of a preamble frame while T 2 is representative of the time duration of a message capsule frame.
Since the preamble time is shortened while still allowing the same number of message data bits to be transmitted, the access channel slot time duration is decreased. Thus the total number of accesses by MSs over a period of time is increased for a greater data throughput.
As shown in FIG. 3, this invention allows the time duration of both the preamble frames and the message capsule frames to deviate from the standards set forth in the prior art IS-95 industry accepted standard.
All of the above calculations used a message capsule frame time duration of 20 ms along with 5 message capsule frames to keep data throughput identical. If message frames were to be decreased fractionally in time duration to more optimally meet data transfer requirements in a given cell, then the protocol efficiency, as described in equations (1) to (3), would be improved; however, the message capsule data efficiency may be decreased as will be discussed below.
The bounds for data efficiency is expressed in equation 4.
(max information data bits per frame)/(Information Bits+Overhead Bits per frame) (4)
An analysis of equation 4 will illustrate that the data efficiency may be increased by increasing any of the items in the numerator while keeping the denominator constant and or by decreasing the denominator.
As an example, if T 2 =19 ms as opposed to the previously assumed 20 ms, the total amount of data transferred in 5 frames would be less. This result occurs because the same number of overhead bits will still be required for each frame thereby leaving less space for load or message data. If however the necessary amount of data can be optimally transferred in five 19 ms frames it may now be determined that the efficiency bounds are potentially as high as (5*0.019)/(17*0.00125+5*0.019) or 0.095/(0.02125+0.095) which equals 81.72%. However, the potential data efficiency for a given access slot is decreased under these assumptions, since the data efficiency is decreased according to equation 4 because the numerator decreases relative to the denominator.
The essence of equation 4 may be expressed in slightly modified format as equation 5.
T 2 *(data rate)/(T 2 *(data rate)+Overhead Bits) (5)
This equation concentrates on the data rate of the message capsule frames to define the bounds of data throughput. In equation (5) the data rate is that of the information bits, wherein ‘data rate’ does not include overhead bits. Since the number of overhead bits per frame normally remains constant, it will be readily apparent that increasing the data rate will of necessity increase or at least maintain the potential data throughput, while decreasing the frame time.
It will be apparent that the present invention is directed to the method of and apparatus for increasing data throughput and access channel efficiency by at least removing the requirement that the frame duration in the preamble and message capsule portions of an access channel slot be identical. The invention further includes the method of and apparatus for altering frame duration times for access channel slots in different cells in a given cellular system.
Although the invention has been described with reference to specific embodiments, these descriptions are not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore, contemplated that the claims will cover any such modifications or embodiments that fall within the true scope and spirit of the invention.
|
A new access channel protocol for use in cellular systems such as CDMA whereby the data transfer efficiency of an access message is increased by removing the requirement that a preamble frame and a message capsule frame have equal times of duration. With such removal, the BTS must inform listening MSs as to the time duration of the frames in each of the preamble and the message portions of the access channel time slot in addition to previously supplied information as to the number of frames in each portion. When unequal frame duration times are allowed, each portion of the access channel may be more nearly optimized to the actual time required to perform the functions of synchronization and message detection.
| 7
|
FIELD OF THE INVENTION
This invention relates to an electro-optic deflector and to a Q-switched laser comprising the electro-optic deflector and, in particular, to a nanopulse laser
BACKGROUND OF THE INVENTION
Following the first operation of a laser in 1960, techniques were quickly developed to generate intense optical pulses (R W Hellwarth in ‘ Advances in Quantum Electronics ’. Columbia Univ Press, New York, p 334-341, (1961) under heading, ‘ Control of Fluorescent Pulsations ’). A simplest and most widely used arrangement involves use of an optical modulator as a component within a laser oscillator to switch the resonance, or ‘Q’, of a resonator from ‘low’ to ‘high’ after the laser medium has been excited. In this way, a round-trip gain of the oscillator is quickly changed from <1 (below threshold) to >>1 (well above threshold), causing fast build-up and emission of an intense optical pulse. If required, this excitation and switching process can be repeated, in some cases at kHz rates (e.g. U.S. Pat. No. 4,761,786, ‘Miniaturized Q-Switched Diode Pumped Solid-State Laser’, Baer T M, 2 Aug. 1988).
This Q-switching technique typically allows optical pulses from miniature lasers in the nanosecond (˜10-50 ns) duration range to be generated with thousands of times the intensity of a non-Q-switched laser beam. The intense pulses are used in a very wide range of commercial and scientific applications, as well as for much research. For example, established applications of the laser pulses include: distance ranging, remote mapping, air-speed measurement, precision marking (metal and non-metal surfaces), fine cutting of refractory materials (gem stones, semiconductors, ceramics, etc), stimulating chemical reactions and measuring fluorescence decay (e.g. via ‘excite and probe’ techniques).
Where short intense laser pulses (in the ˜10 ns duration range) are required, high speed phase modulators based on Pockels effect solid-state electro-optic (E-O) materials have been widely used in the Q-switch. In a most successful arrangement, the Q-switch comprises a Pockels effect modulator in combination with a polarising element. An electric field, applied by electrodes to the E-O material of the modulator, induces a change in refractive index proportional to the electric field strength. This change in refractive index produces a phase difference between orthogonal polarisation components in the laser radiation field, and a high optical loss at the polariser results. Removing the electric field from the modulator removes the optical loss at the polariser i.e. the Q of the laser can be rapidly switched low and high by switching the E-O modulator voltage on and off (Koechner W. ‘ Solid - State Laser Engineering ’, Ch 8 Q - Switching . p 469-519. (1998), 5 th Edition. Publ by Springer-Verlag, NY, ISBN 3-540-65064-4).
In an alternative scheme Zayhowski (‘ Diode - Pumped Microchip Lasers Electro - Optically Q - Switched at High Pulse Repetition Rates’. Optic Letters . p 1201-3, Vol 17, No 17, 1 Sep. 1992, and U.S. Pat. No. 5,381,431, ‘Picosecond Q-Switched Microlasers’, 10 Jan. 1995) disclosed a novel arrangement that eliminates the polariser and allows miniaturisation by using an E-O phase modulator in the form of a variable thickness optical etalon. In this case, E-O crystal faces are finely polished parallel and made partially reflecting at the selected laser wavelength. By application of a voltage, a resultant small change in refractive index is used to change effective reflectivity (feedback) of the modulator into the miniature laser resonator of which it is a part. In this way, the resonator Q can be switched high/low by application of a controlled voltage step to the E-O crystal. In practice, this coupled laser resonator is very difficult to implement as many factors must be favourable if reliable and consistent performance is to be achieved, for example problems arise because the Q of the 3-element etalon (which comprises the resonator) is sensitive to temperature distribution (pump power/gain), the required mechanical alignment of parts is very high, the change in Q is sensitive to voltage (Q-switch circuit), and the laser operating wavelength (longitudinal mode) may ‘hop’ under switching conditions. For these reasons and others, the arrangement is believed not to have been implemented outside of a laboratory environment and not to be practicable.
Rather than generating a phase difference between orthogonal polarisation components, the Pockels effect in an E-O material can be used to produce fast optical modulation by beam deflection. Such a gradient deflector 10 is illustrated in FIG. 1 , where by generating a small gradient of the refractive index, from n o −Δn to n o +Δn, across an input beam 11 , an output beam 12 is deflected i.e. the modulator acts like a weak optical prism (Fowler V J. Buhrer C F, and Bloom L R, Proc IEEE ( Corres ). 1964, February 1964). Referring to FIG. 2 , in 1968, Lotspeich described the use of a quadrupole electrode arrangement 20 to generate a necessary field and resultant refractive index gradient in a potassium dihydrogen phosphate (KDP) type E-O material (Lotspeich J F, ‘ Electrooptic Light - Beam Deflection’, IEEE Spectrum , p 45-52, February 1968). FIG. 2 is a cross-sectional schematic diagram of a quadrupole array of parallel-rod electrodes 21 to produce a linear variation of refractive index in an x direction within a KDP-type electro-optic material. The proper crystallographic orientations of the <001> and <110> directions are indicated. This deflector type of E-O modulator was proposed for use as an alternative practical laser Q-switch in 1979 (Ireland C L M, ‘ Some Design Considerations and Applications of a Fast Crystal Deflector ’, in Proc IV Quantum Electron Conf Edinburgh , pp 87-91, 1979. Pub Wiley, NY (1980)) and a Q-switch, following a design similar to that of FIG. 2 using lithium tantalate (LiTaO 3 ) as the E-O material, was subsequently demonstrated (Friel G. J. Conroy R S, Kemp A. J, Sinclair B D and Ley J M, ‘ Q - Switching of a Diode - Pumped Nd:YVO 4 Laser Using a Quadrupole Electro - Optic Deflector’, Appl Phys B , Vol 67, p 267-270 1998).
In principle, the E-O deflector type Q-switch has a number of important advantages over the longer established phase difference type. Unlike the latter, the E-O deflector type Q-switch does not rely on a polariser element to complete the switch. This offers the potential of simplicity of design (single component), greater optical efficiency (reduced optical loss for the resonator in the high-Q state) and reduced optical length (miniaturisation). In the last case, miniaturisation is critical to achieve the shortest pulses from a Q-switched laser, since pulse length scales with resonator (optical) length, provided that good hold-off of the resonator round-trip gain is maintained by the Q-switch in its off (low-Q) state.
Although it has potential advantages as a Q-switch, the deflector type modulator has weaknesses and limitations and it is an objective of this invention to provide key improvements and developments that at least mitigate them. A specific objective is to provide a Q-switch suitable for miniaturisation and use in generating very short, high energy, Q-switched laser pulses e.g. pulses of >10 μJ in the ˜100-1000 ps range. Such pulses are very attractive for many applications e.g. (i) for increasing measurement resolution in applications like ranging, aerial mapping and fluorescence diagnostics, and (ii) significantly to improve fine processing results in materials interactions/modification—see for example US 2005150880, 14 Jul. 2005 to Gu and Smart which teaches the clean breaking of memory links in semiconductor circuits.
To achieve short optical pulses it is well known that a laser resonator requires, (i) a high gain laser material e.g. crystal Nd:YAG, Nd:YVO 4 or Nd:GdVO 4 , (ii) to be excited by a high power source such as a focused beam from a laser diode, and (iii) to use a very short optical resonator. The principles have been widely discussed—see for example, Koechner (1998) ibid and ‘ Theory of the Optimally Coupled Q - Switched Laser ’, Degnan J J, IEEE Journal of Quant Electronics , Vol 25, No 2, pp 214-20, (1989). In the case of generating very short duration (i.e. ˜100-1000 ps range) pulses, it is expected that the resonator optical length correspondingly must be very short and in the ˜5-15 mm range and the deflector Q-switch, located within the resonator, necessarily be only a few millimeters long i.e. of optical length typically <10 mm.
Since the first operation of the laser, new E-O materials have been identified or developed. In particular, recently rubidium titanyl phosphate (RTP) has become available with some attractive characteristics for use in optical modulators (Lebiush E, Lavi R, Tsuk Y. Angert N, Gachechiladze A, Tseitlin M, Zharov A. and Roth M. in: Proc of the Topical Meeting on Adv Solid - State Lasers , Davos, Switzerland, Trends in Optics & Photonics , Vol 34, p 6370, (2000)). The best E-O materials are single crystals, usually difficult to grow in high optical quality and are thus expensive to produce in usable size. They are often fragile and require specialist skills to work to the required optical standards/tolerances i.e. manufacturing yield can be poor.
Referring to FIG. 1 , the beam deflection ΔΦ of a modulator based on an E-O material exhibiting the Pockels effect depends on the crystal aspect ratio (L/W), the appropriate E-O coefficient (r) for the material, and the electric field (E) in the appropriate direction at the aperture limit through the relationship:
ΔΦ˜(L/W)·n o 3 ·r·E (1)
Here n o is the refractive index in the appropriate direction of the E-O crystal 13 , and L·n o the optical length. The E-O effect is weak and high electrical field strengths (E typically ˜100-2000V/mm) are required to achieve a useful optical effect. For example, with RTP, LiTaO 3 or LiNbO 3 the E-O coefficient r is ˜30 pm/V and n o is ˜2, so that a deflector of ×10 aspect ratio requires a field in the 300V/mm range to provide a milliradian beam deflection. When used as a Q-switch of a high gain laser, the modulator needs to provide a deflection comparable to the laser beam divergence when switching the resonator between low- and high-Q, so as to inhibit losing in the low-Q state. For a miniature solid-state laser with a TEMoo mode beam this angle is typically in the range of a few milliradians (e.g. 2-10 milliradians).
With a sustained high applied electric Field, materials can develop internal crystal damage—ferroelectric domain reorientation and/or ion migration; the latter leading to what appears as ‘grey-tracks’ in the high field region(s) of the crystal. In addition, the high drive power coupled with the finite conductivity of the material leads to heating that can adversely affect the optical quality of the crystal, distorting the transmitted laser beam via thermo-optic effects if not adequately dissipated.
Many E-O materials exhibit a reverse piezoelectric effect (‘ Analysis of the Acoustic Transients in the Pulse Response of the Linear Electro - Optic Effect ’. Veeser H, Bogner U, and Eisenmenger W, Phys Stat Sol ( a ). Vol 37, p 161-70, 1976). When a pulsed high electric field is applied in these materials it leads to the generation of acoustic waves and resonances, which if not adequately damped, distort and aberrate the optical beam being modulated.
A further complication affecting modulator design is that, to different degrees, E-O materials exhibit optical absorption at laser wavelengths. This comprises a normal (small) linear absorption component and sometimes, under high optical fields, a significant non-linear absorption component e.g. due to the Raman effect (‘ Solid - State Raman Laser Generating < Ins Multi-Kilohertz Pulses at 1096 nm ’, Pearce S. Ireland C L M, and Dyer P E, Optics Comm Vol 260, p 680-6, 2006). The latter shows up as a power loss via acoustic phonon generation from the optical beam and results in additional heat generation in the Q-switch. If not adequately dissipated, the heat leads to laser beam distortion and aberration via thermo-optic effects.
These difficulties mean that it is most advantageous to design E-O modulators for Q-switches to use short duration voltage pulses of as low amplitude as possible, and include a means of good heat dissipation from the E-O material in their mounting, particularly in the case of high repetition-rate and/or high average laser power applications.
Finally, to different degrees, E-O materials are susceptible to induced optical damage at high laser power densities. A laser damage threshold typically ranges from a few ×10 MW/cm 2 to several ×1 GW/cm 2 depending on the material and its purity, and this effect greatly limits the choice of E-O materials for practical use in laser applications. The recently grown E-O material RTP and some isomorphs (e.g. KTP in high resistivity form) have relatively good damage resistance to laser intensity and are good candidates in this respect for use in a laser Q-switch
For a deflector type laser Q-switch, the prior art comprises a uniform (undistorted) beam deflection using a single E-O crystal with a quadrupole electrode arrangement to produce a near linear electric field gradient in the material as illustrated in FIG. 2 . Lotspeich (1968) taught that an optimum quadrupole configuration comprised four electrodes 21 each with a hyperbolic profile running in the beam direction over the length of the crystal 22 , suitably orientated to exploit the maximum E-O effect for the particular material. A cross-section of the Lotspeich arrangement with KDP as the E-O material is shown in FIG. 2 . In this case, a beam propagating in the z-axis direction, into the plane of FIG. 2 , is deflected in the x-z plane when voltage is applied as shown to the quadrupole electrodes 21 . FIGS. 3 a and 3 b illustrate Q-switched laser resonators 30 in which a Nd:YAG crystal 31 is pumped by a pump diode 32 through an optical fibre 33 . Pump light emergent from the fibre is focussed onto a first end face of the Nd:YAG crystal by a focussing lens 34 . This first face of the Nd:YAG crystal is coated to be highly reflective at the laser wavelength and transmissive at the pump wavelength. Laser light emergent from a second end face of the Nd:YAG crystal passes though a first end face of the E-O material deflector 20 . Laser light emergent from a second end face of the deflector 20 is incident on a partially reflective mirror 35 . In use, an angle change ΔΦ imposed on the beam by the deflector allows the beam deflector to be used as a Q-switch for the laser resonator 31 , 20 , 35 , either, as in FIG. 3 a , using an applied voltage V 0 to switch the resonator Q (i.e. effectively alignment of the mirror 35 ) from low to high, or, as shown in FIG. 3 b , from high to low.
As noted previously, in effect, the deflector 20 acts as a small angle optical prism where the angle ΔΦ can be turned on/off in a controlled manner by applying the voltage V 0 and electric field to the crystal. The optical switching speed is as fast as the electric field switching speed which is primarily determined by the electrical capacitance of the Q-switch i.e. to achieve a fast deflector requires a low capacitance and high driving current (see p 76-80 in ‘ Electro - Optic and Acousto - Optic Scanning and Deflection ’, Gottlieb M, Ireland C L M, and Ley J M, in Optical Engineering Series , Pub 1983 by Marcel Dekker Inc; NY. ISBN:0-8247-1811-9).
Since electrodes 21 of hyperbolic profile are very difficult to fabricate. Ireland (1979) calculated the effect on field linearity of replacing hyperbolic electrodes by simpler cylindrical electrodes in the quadrupole configuration. He showed that, with an appropriate choice of radius, cylindrical electrodes could be used without introducing a severe field distortion which, otherwise, would have led to optical aberration being impressed on the beam. In this case, the estimated wavefront aberration was ˜λ/2 (where λ was the optical wavelength), and was at least no worse than that calculated due to the grinding and positional errors of the electrodes in the fabrication of the device. Using LiNbO 3 as the E-O material, Ireland (1979) reported beam deflection experiments validating his design.
Whether based on prior-art hyperbolic or the simpler cylindrical shape, the quadrupole electrode arrangement for a deflector Q-switch is very difficult to manufacture, and becomes particularly so as the deflector size is scaled-down into the millimeter range. In the ‘wings’ 23 (region of highest electric field—see FIG. 2 ) of the crystal 209 , the thickness becomes very small (i.e. significantly less than 1 mm) and breakage during fabrication readily occurs in this area. When attempting further miniaturisation of the Q-switch, the required electrode grinding and positional tolerances translate into progressively tighter control of dimensions i.e. the tolerances move into the few microns range. Such alignment is extremely difficult to achieve in the case of four electrodes 21 , which not only must be aligned relative to the appropriate axes of the E-O crystal 209 , but to each other. For these reasons, the miniaturisation of the prior-art is severely limited. An additional important constraint of the prior-art is the difficulty of mounting the shaped E-O crystal to provide good heat removal and acoustic damping without inducing stress or breakage when employed as a laser Q-switch.
It is an object of the present invention at least to ameliorate the aforesaid disadvantages in the prior art.
SUMMARY OF THE INVENTION
According to a first aspect of the invention there is provided an electro-optic deflector comprising an electro-optic material for passing an optical beam therethrough and no more than three longitudinal electrodes, comprising one of: two mutually inclined planar electrodes; and one or two electrodes with arcuate transverse cross-sections, arranged to create an electric field gradient substantially transverse to a direction of the optical beam to deflect the optical beam passing between the electrodes.
Conveniently, the electro-optic deflector comprises: a longitudinal arcuate electrode with an outwardly concave cross-section forming substantially a quadrant of a circle and having an axis substantially parallel to a direction of the optical beam; a first planar longitudinal electrode having a major axis substantially parallel to the direction of the optical beam and substantially parallel to a first tangent to the arcuate electrode at a first end of the arcuate electrode and spaced therefrom; and a second planar longitudinal electrode orthogonal lo the first planar electrode and substantially parallel to the direction of the optical beam and substantially parallel to a second tangent to the arcuate electrode at a second end of the arcuate electrode and spaced therefrom; wherein the electrodes form a single quadrant of an otherwise quadrupole array.
Optionally, the electro-optic deflector comprises: a first longitudinal arcuate electrode with an outwardly concave cross-section forming substantially a quadrant of a circle and having an axis substantially parallel to a direction of the optical beam; a second longitudinal arcuate electrode, mirroring the first arcuate electrode, with an outwardly concave cross-section forming substantially a quadrant of a circle and having an axis substantially parallel to a direction of the optical beam a first planar longitudinal electrode substantially parallel to the direction of the optical beam; and a planar longitudinal electrode substantially parallel to the direction of the optical beam and to a tangent to the arcuate electrode at a first end of the first arcuate electrode remote from the second arcuate electrode and parallel to a tangent to the second arcuate electrode at an end of the electrode remote from the first electrode and spaced therefrom; wherein the electrodes form two quadrants of an otherwise quadrupole array.
Optionally, the electro-optic deflector comprises: a longitudinal arcuate electrode with an outwardly concave cross-section forming substantially a quadrant of a circle and having an axis substantially parallel to a direction of the optical beam; a first planar longitudinal electrode having a major axis substantially parallel to the direction of the optical beam and substantially parallel to a second tangent to the arcuate electrode cross-section at a second end of the arcuate electrode and spaced therefrom; wherein the electrodes form a single quadrant of an otherwise quadrupole array except that the electro-optic material extends substantially further in a direction of the second tangent orthogonal to the beam direction and substantially orthogonal to a first tangent to the arcuate electrode at a first end of the arcuate electrode cross-section than in a direction of the first tangent.
Optionally, the electro-optic deflector comprises: a first longitudinal arcuate electrode with an outwardly concave cross-section forming substantially a quadrant of a circle and having an axis substantially parallel to a direction of the optical beam; a second longitudinal arcuate electrode, mirroring the first arcuate electrode, with an outwardly concave cross-section forming substantially a quadrant of a circle and having an axis substantially parallel to a direction of the optical beam a first planar longitudinal electrode substantially parallel to the direction of the optical beam, wherein the electrodes form two quadrants of an otherwise quadrupole array except that the electro-optic material extends substantially further in a direction orthogonal to the beam direction and substantially orthogonal to a tangent to the first and second arcuate electrodes at ends of the cross-sections of the arcuate electrode remote from each other, than in a direction of the tangent.
Optionally, the electro-optic deflector comprises: a longitudinal arcuate electrode with an outwardly concave cross-section forming substantially a semicircle and having an axis substantially parallel to a direction of the optical beam; a planar longitudinal electrode having a major axis substantially parallel to the direction of the optical beam and substantially parallel lo a tangent to the arcuate electrode cross-section at a midpoint thereof and spaced therefrom; wherein the electrodes form two quadrants of an otherwise quadrupole array except that the electro-optic material extends substantially further in a direction orthogonal to the beam direction and substantially in a direction of the planar electrode than in a direction orthogonal thereto.
Optionally, the electro-optic deflector comprises: a first planar longitudinal electrode having a major axis substantially parallel to the direction of the optical beam; a second planar longitudinal electrode, inclined to the first planar electrode, having a major axis substantially parallel to the direction of the optical beam; wherein the electro-optic material extends substantially further in a direction orthogonal to the beam direction and away from the planar electrodes than in a direction orthogonal thereto.
Conveniently, the second planar electrode is inclined to the first planar electrode at substantially a right angle and the electro-optic material extends in a direction at substantially 45 deg. to the first planar electrode and the second planar electrode.
Alternatively, the second planar electrode is inclined to the first planar electrode at substantially 45 deg. and the electro-optic material extends in a direction defined by the second planar electrode.
Preferably, the electro-optic material extends sufficiently to provide a purchase for holding the material during forming of the electrodes.
Advantageously, the electro-optic material extends sufficiently to provide a surface area sufficient for efficient heat conduction and dissipation to a mount of the deflector.
Advantageously, the electro-optic material extends sufficiently to provide a surface area sufficient for damping acoustic waves via appropriate acoustic impedance to a mount of the deflector.
Preferably, the electro-optic deflector has an optical length of no more than 10 mm.
Preferably, the optical beam deflection is at least 1 mrad.
Conveniently, the electro-optic material is rubidium titanyl phosphate (RTP).
Conveniently, the electro-optic material is high resistivity potassium titanyl phosphate (KTP).
According to a second aspect of the invention, there is provided a Q-switched laser for generating sub-nanosecond duration optical pulses comprising an electro-optic deflector comprising an electro-optic material for passing an optical beam therethrough and no more than three longitudinal electrodes, comprising one of: two mutually inclined planar electrodes; and one or two electrodes with arcuate transverse cross-sections, arranged to create an electric field gradient substantially transverse to a direction of the optical beam to deflect the optical beam passing between the electrodes.
Conveniently, the Q-switched laser comprises laser gain material of one of Nd:YAG, Nd:YVO 4 and NdGdVO 4 .
Advantageously, the Q-switched laser is diode pumped.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a prior art gradient E-O deflector modulator;
FIG. 2 is a cross-sectional view of a known quadrapole array of electrodes for use in the deflector of FIG. 1 ;
FIGS. 3 a and 3 b are schematic diagrams of Q-switched oscillators using electro-optic deflectors;
FIG. 4 a is a cross-sectional view of a first two quadrant embodiment of an E-O deflector according to the invention;
FIG. 4 b is a cross-sectional view of a first one quadrant embodiment of an electro-optic deflector according to the invention;
FIG. 5 a is a cross-sectional view of a second two quadrant embodiment of an electro-optic deflector according to the invention;
FIG. 5 b is a cross-sectional view of a second one quadrant embodiment of an electro-optic deflector according to the invention;
FIG. 5 c is a cross-sectional view of a further two-quadrant embodiment of an electro-optic deflector according to the invention;
FIG. 6 a is a graph of pulses produced by a laser using an electro-optic deflector according to the invention;
FIG. 6 b is a graph of a calculated electric field in a Q-switch according to the invention;
FIG. 7 a is a cross-sectional view of a first two-plane electrode embodiment of an electro-optic deflector according to the invention; and
FIG. 7 b is a cross-sectional view of a second two-plane electrode embodiment of an electro-optic deflector according to the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Throughout the description, identical reference numerals are used to identify like parts.
Referring to FIG. 2 , in principle, a field gradient of a Q-switch of quadrupole design with perfect hyperbolic electrodes 21 (correctly positioned), is constant in the required deflection direction across its full aperture. As a result, it is not necessary for a laser beam to pass through a centre of the Q-switch. For a fixed voltage applied to the electrodes, at any location in the aperture, the beam will be subject to the same deflection.
From FIG. 2 , it can be seen that a quadrupole electrode 21 configuration gives rise to two orthogonal planes of symmetry 24 , 25 intersecting at a centre of the device 20 . The planes are equi-potential surfaces, and in this case the constant potential is zero. The crystal orientation, axes for the planes, is dependent on the deflector material, and chosen to use the E-O effect that maximises the deflection angle. Lotspeich (1968) uses KDP for the E-O material, and the planes are y-z and x-z, intersecting along the origin in the z-axis direction. In the case where LiNbO 3 is used as the E-O material by Ireland (1979), the equi-potential planes arc y-z and x-y, intersecting through the origin in an y-axis direction.
As a consequence of the electric field symmetry, it will be seen from FIG. 2 that it is possible to consider a quadrupole E-O deflector as comprising either; (i) two similar halves or (ii) four similar quadrants. This allows new deflectors to be conceived giving a same beam deflection. Using plane electrodes 415 ; 425 , 427 (equi-potential surfaces) positioned along what would have been one or both of the symmetry planes 24 , 25 , possible Q-switches of simpler geometry result. FIGS. 4 a and 4 b show electrode arrangements 411 , 412 ; 421 , which are arcuate in cross-section, of these two new deflectors 41 , 42 . In the case of the first deflector 41 , illustrated in FIG. 4 a , the deflector corresponds to two quadrants of the known quadrupole deflector 20 illustrated in FIG. 2 so that the number of shaped electrodes 411 , 412 is reduced from four in the prior art to two, with one plane electrode 415 . In the embodiment 42 illustrated in FIG. 4 b the deflector 42 corresponds to only one quadrant of the known quadrupole deflector 20 illustrated in FIG. 2 so that there is only one shaped electrode 421 and two mutually orthogonal plane electrodes 425 , 427 . To make use of deflectors of either geometry it is self-evident that the beam 46 must be displaced from the origin, that is the intersection of the two symmetry planes 24 , 25 of the original quadrupole electrodes 21 , anywhere into the clear aperture region of each new deflector 41 , 42 . In FIGS. 4 a and 4 b the circles 46 indicate possible beam positions.
Although simpler, the geometry of each deflector 41 , 42 illustrated in FIG. 4 a and particularly in FIG. 4 b , respectively, can be improved to: (i) considerably reduce crystal fabrication problems, (ii) allow easy mounting to remove waste heat and to damp acoustic waves, and (iii) facilitate miniaturisation (particularly reduction of crystal length L) to provide a simple, very short Q-switch for a miniature laser i.e. achieve optical length L·n o in the range below 10 mm.
As noted earlier, the location of the laser beam 46 in an aperture of a quadrupole deflector 20 is not critical to Q-switch operation e.g. performance is tolerant to the transverse position of the beam 46 relative to the aperture centre. It will be understood that, due to symmetry, this is also the case for the deflectors 41 and 42 illustrated in FIGS. 4 a and 4 b with simpler electrodes 411 , 412 ; 421 . With the known quadrupole deflector 20 , when the beam 46 is so located towards one of the wings 23 (high field region) of the crystal, the contribution to the field from the two nearer electrodes 21 increases, and that from the other pair decreases. In the limit (towards the extreme of the aperture) the two closest electrodes 21 dominate in controlling the linear field gradient. This can be seen from the electric field lines indicated schematically in FIG. 2 from Lotspeich (1968) i.e. where the field lines become short and close to unidirectional.
This dominance of the contribution of the nearest electrodes 21 to the electric field (in the case where the laser beam 46 is directed through the high field region 23 ), allows the deflector geometries of FIGS. 4 a and 4 b to be simplified further. New Q-switch deflector options 51 , 52 , 53 result, indicated schematically in FIGS. 5 a , 5 b and 5 c . It will be seen that the deflector 51 in FIG. 5 a is developed from deflector 41 illustrated in FIG. 4 a . The positioning of the laser beam 46 towards the high field region allows dispensing with the zero potential electrode (the vertical electrode 415 in the schematic of FIG. 4 a ) and most importantly, extension of the E-O crystal 519 to a convenient dimension transverse to the beam direction i.e. in the horizontal direction in FIG. 5 a . Similarly, it will be seen that the deflector 52 in FIG. 5 b (developed from deflector 42 illustrated in FIG. 4 b ) is of particularly simple design. The positioning of the laser beam 46 towards the high field region allows removal of one of the zero potential electrodes (the vertical electrode 425 in the schematic of FIG. 4 b ) and, most importantly, extension of the E-O crystal 529 to a convenient dimension transverse to the beam direction i.e. in the horizontal direction in FIG. 5 b . The result is additional simplification of the electrode geometries, and the opportunity to make the E-O crystals 519 and 529 arbitrarily large in a non-critical direction. The latter is an important advantage as it overcomes a practical limitation of short length in the handling and fabrication (e.g. optical polishing, fine grinding, electroding and AR coating of the optical faces) of miniature aperture deflector crystals e.g. for use as a fast Q-switch. In the case of the extended single quadrant deflector 52 shown in FIG. 5 b , it also provides an opportunity of simple mounting of the E-O crystal 529 with the plane electrode 527 against a suitable plane surface for efficient heat dissipation and acoustic damping.
FIG. 5 c represents a deflector 53 which is a more practical two-quadrant extension of the simple transversely extended deflector 52 of FIG. 5 b . The deflector 53 retains the attractive features noted above but, importantly, also mitigates the risk of electrical tracking/breakdown over the short distance between the electrodes 521 , 527 around the very narrow tip of the crystal in the single-quadrant extended deflector 52 illustrated in FIG. 5 b . The improved mirrored-quadrant extended deflector 53 shown in FIG. 5 c , uses a same basic geometry as the extended single quadrant deflector 42 but the shaped crystal 539 includes a ‘mirror image’. In the case of this improved design, a same simple cylindrical profile electrode 531 can be used but without risk of the very short surface tracking distance of the single quadrant deflector 42 . Further practical advantages of the modified mirrored-quadrant deflector 53 of FIG. 5 c are that it: (i) facilitates straightforward jigging for the accurate grinding of the cylindrical electrode 531 , and (ii) provides redundancy i.e. two possible mirror-image locations 461 , 462 , as indicated, are available for the position of the laser beam through the device to provide Q-switching.
FIG. 6 shows an image 61 recorded from an oscilloscope of a ˜500 ps duration TEMoo pulse of ˜20 μJ energy from a miniature Nd:YVO 4 laser operating at 5 kHz and which incorporated a ˜5 mm optical length Q-switch of the mirrored quadrant deflector 53 illustrated in FIG. 5 c.
FIG. 6 b shows a calculated plot of an electric field in the mirrored quadrant deflector 53 illustrated in FIG. 5 c for a 500 V applied pulse. It is apparent that there are two symmetric regions 62 , 63 where there is an approximately linear field gradient. Each region extends over approximately 0.4 mm, which is suitably approximately twice a diameter of a suitable laser beam.
It will be understood that with some high resistivity stable E-O materials, it is possible to operate a deflector modulator with a field applied for considerable time periods without deleterious effects occurring. In this case, the deflector Q-switch operating mode of FIG. 3 b becomes a practical option. Here, the Q-switch operates in the mode where the applied voltage (V) is high to provide a low-Q resonator (for the extended period while the laser gain medium is excited), followed by V low (ie V˜0 Volts) to give the resonator high-Q, and allow rapid laser pulse generation and emission.
Most importantly, in this mode of operation, the laser pulse is generated and emitted under conditions where there is substantially no voltage (V˜0 Volts) on the Q-switch. As a result, the uniformity of the field gradient with V high on the deflector is not important to laser performance. With V high, the key requirement is only that the deflector sufficiently lowers the resonator Q as to inhibit laser oscillation. It will be understood that a uniform beam deflection across the beam aperture (i.e. as provided by a linear field gradient) is not particularly required in this case. Other field distributions provided by much simpler electrode geometries applied to the deflector become possible for a practical Q-switch operating in this mode.
FIGS. 7 a and 7 b show two examples of possible crystal and electrode geometries 71 , 72 for Q-switches based on the immediately preceding discussion. They are modifications of the preferred deflectors 51 , 52 illustrated in FIGS. 5 a and 5 b , respectively, but with the requirement to provide a near constant electric field gradient dropped. In both the deflectors 71 , 72 of FIGS. 7 a and 7 b the electrodes 711 , 712 ; 721 , 722 are plane and, for convenience, inclined to each other by ˜90° and ˜45°, respectively—although other angles will be similarly effective. FIGS. 7 a and 7 b represent examples of the simplest (i.e. two electrode) geometry deflectors possible for a deflector Q-switch using an electric field gradient.
By inspection of FIGS. 7 a and 7 b , it is readily seen that the length of the field lines between the electrodes increases approximately linearly with distance from the apex A of the crystal i.e. the electric field decreases highly non-linearly. approximately hyperbolically, with distance, with the gradient highest closest to the apex A. As a result, with the electric field applied, laser beam deflection changes with distance from the apex, and is highest close lo the apex.
Used as a laser Q-switch, the hold-off of resonator gain by the deflectors 71 , 72 of FIGS. 7 a and 7 b can be set by a combination of deflector voltage and position, i.e. location of the beam 46 relative to the crystal apex A. As with the Q-switch deflectors 51 , 52 in FIGS. 5 a and 5 b , those of FIGS. 7 a and 7 b retain similar practical benefits associated with fabrication, miniaturisation, ease of mounting for waste heat dissipation and acoustic damping.
It will be apparent to those skilled in the art of E-O crystal preparation and use that the embodiments 51 , 52 , 53 , 71 , 72 of deflector Q-switches in FIGS. 5 a , 5 b , 5 c and FIGS. 7 a and 7 b require care in their implementation, (i) to avoid leakage current/breakdown by surface tracking over the crystal surfaces between electrodes at different potentials, (ii) to minimise stress during plating of electrodes and crystal mounting, and (iii) in the choice of compatible materials for heat conduction and damping for a practical and reliable Q-switch. It will also be apparent to those skilled in the art that the E-O deflectors disclosed will have many other applications for optical beam deflection and modulation besides use as a fast laser Q-switch, and that operation with high bandwidth and/or high pulse repetition rate requires careful design of the electronic switching or modulating circuit, including the electrical connections to the deflector
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.
|
An electro-optic deflector 51 has an electro-optic material body 519 through which an optical beam 46 is passed. The deflector has no more than three longitudinal electrodes, of which no more than two electrodes 511, 512 have arcuate transverse cross-sections. The electrodes are arranged to create an electric field substantially transverse to a direction of the optical beam to deflect the optical beam passing between the electrodes. The electro-optic deflector has particular application in a Q-switched laser for generating sub-nanosecond optical pulses.
| 6
|
FIELD OF THE INVENTION
This application relates to structurally organized polymers, and to methods for their preparation. More particularly, this invention relates to the preparation of polymers with ordering mesogens contained therein that can be polymerized in ordered layers. Specifically, this invention relates to mesogen-containing monomers separated from reactive groups on the two ends thereof by spacer atoms, such monomers being capable of polymerization to form ordered molecular structures.
BACKGROUND OF THE INVENTION
In carrying out homogeneous polymerizations with typical monomers, the reactive sites on the separate monomer molecules are located relatively far from each other. Consequently, in order for the polymerization reaction to proceed, the monomer molecules must be sufficiently mobile within the reaction mixture so that they can diffuse to locations that bring the reactive sites into contact with each other. Unfortunately, as the polymerization reaction proceeds, the glass transition temperature, T g , of the forming polymer rises as the conversion increases, reducing the rate of diffusion of the monomer molecules within the mixture, and slowing the polymerization as a result. Consequently, it is impossible to obtain a high T g polymer by polymerizing monomeric materials in an isotropic state at low temperatures because of the inhibiting influence of the rising T g . Stating the effect differently, when molecular diffusion ceases, a polymerization reaction is no longer possible, seriously limiting the degree of reaction completion that can be achieved with homogeneous polymerizations. Since it is necessary to increase the reaction temperature during the polymerization to maintain a practical rate of diffusion, it is impossible to achieve substantial polymerizations at low temperature.
By way of contrast, where the reaction sites of the monomer molecules in heterogeneous polymerizations can be maintained in spatially adjacent positions, relatively complete reactions can be obtained even in substantially molecularly immobile systems. Consequently, heterogeneous polymerization systems in which the reacting monomers are structured to possess ordering moieties or segments, offer the possibility of obtaining polymerizations yielding polymers with substantial glass transition temperatures, in relatively complete conversions. This is true even at reactive temperatures substantially below the resulting polymers' glass transition temperatures, since it is unnecessary to promote molecular diffusion by heating the reaction mixtures.
Liquid crystalline and crystalline materials contain such ordering segments in the form of rigid portions, termed "mesogens". Such materials are capable of molecular ordering, including nematic and smectic ordering, in which the molecules arrange themselves in heterogeneous adjacent, molecular configurations wherein the molecules are aligned in parallel relationship to each other.
Thermotropic liquid crystalline monomers and polymers have been intensely studied during recent years, the primary interest up to the present time being the temperature ranges in which liquid crystalline formations can be observed, as well as the relaxation times, or "creep" rates shown by the materials. Difunctional vinyl monomers which exhibit liquid crystalline behavior have, for example, been synthesized and heterogeneously polymerized to form cross-linked polymers by Strzelecki et al, Bull. Chem. Soc. de France 2,597,603,605 (1973). The resulting polymers thus produced, however, are brittle, crystalline materials, lacking the "toughness" required for products capable of widespread application.
Various other organized or liquid crystalline systems which, however, possess a single functional group, have also been employed. For example, styrene- sulfonic acid organized by reaction with ionenes has yielded cationic polymers in reactions displaying appreciable rate enhancements over those of homogeneous monomers at the same concentration. Ionenes have also been used in the past by Tsuchida et al., J. Polymer Sci. 13, 559 (1975), to increase the rates of methacrylic and acrylic acid polymerizations. Konstantinov et al., Vysokomol. Soed., 9A 2236 (1967) has polymerized methacrylyl oxybenzoic in the liquid crystalline state at higher rates, than those obtained in the isotropic state. Cholesteric liquid crystalline monomers, e.g., cholestryl methacrylate, have been polymerized by Saki et al., Polymer J., 3, 414 (1972), at rates considerably more rapid than those obtained during the polymerization of such materials in the isotropic state at even higher temperatures. The polymerization of monofunctional monomers, however, yields polymers with large side chains; consequently, polymers so produced tend to yield high T g , brittle materials, again limiting their usefulness.
BRIEF DISCLOSURE OF THE INVENTION
In view of the foregoing, therefore, it is a first aspect of this invention to provide monomers with functional end groups, separated by spacer atoms from the mesogens contained in the monomers.
It is a second aspect of this invention to provide a way in which monomers can be polymerized at temperatures that include those substantially below the glass transition temperatures of the resulting polymers.
Another aspect of this invention is to produce polymers with high glass transition temperatures, employing low temperature reactions.
A further aspect of this invention is to provide monomers that can be polymerized without any need to promote the diffusion of the monomers throughout the reaction medium during the polymerization by the application of heat.
An additional aspect of this invention is to provide tough, molecularly ordered polymers, which show valuable electrical and other unique properties, useful in a variety of applications.
A still further aspect of this invention is to provide heterogeneous polymerization systems in which reactive sites are positioned adjacent to each other, facilitating the ease and speed of their chemical interaction.
Yet a further aspect of this invention is to provide polymerization systems in which substantially all of the cross-linking reaction sites interact with each other.
An additional aspect of this invention is to provide highly polymerized systems possessing molecular order, which exhibit a wide range of desirable physical properties.
A further aspect of this invention is to produce polymers characterized in having anisotropic structural features.
The foregoing and additional aspects of the invention are provided by liquid crystalline and crystalline monomer molecules useful in preparing polymeric structures possessing molecularly ordered regions therein, comprising mesogen-containing molecules, said mesogens having two side chains attached thereto that contain functional groups at the ends thereof, wherein said mesogens and said functional groups are separated by at least two to about eighteen spacer atoms.
The foregoing and other aspects of the invention are provided by the process of preparing polymeric structures possessing molecularly ordered regions comprising polymerizing mesogen-containing monomer molecules, said mesogens having two side chains attached thereto that contain a functional group at the ends thereof, wherein said mesogens and said end groups are separated by at least two to about eighteen spacer atoms, that includes polymerizing said molecules at a temperature no higher than the temperature required to maintain or generate, at least some molecular ordering.
The foregoing and still further aspects of the invention are provided by a polymer prepared by polymerizing a monomer according to the penultimate paragraph.
DETAILED DESCRIPTION OF THE INVENTION
Certain types of molecules, referred to as "smectic liquid crystalline materials," are capable of ordering themselves in a mesomorphic state in which the molecules are arranged in a lamellar structure, with all, or substantially all of the molecules locally lying parallel to each other. When so ordered, the molecules within a domain form parallel adjacent layers due to the mesogens contained in the molecules, which tend to position themselves adjacent to each other as a result of their spatial configurations. Since the side chains of the liquid crystalline molecules contemplated by the invention, located on both sides of the mesogen groups, are substantially the same in length, the ends of the side chains are juxtaposed to each other in adjacent structures or layers.
Liquid crystalline materials of the type described normally assume an ordered form at temperatures from about 10° to 90° C., and they tend to be relatively small molecules. The liquid crystalline and crystalline materials are rather turbid in appearance until their temperature is increased above their "clearing temperature", where the turbidity disappears as the materials enter the isotropic region. While much of the crystalline ordering disappears above the clearing temperature, some ordering of the molecules is still present even at temperatures somewhat above the clearing point.
When reactive end groups are incorporated at the ends of the monomeric materials, their adjacency permits them to interact even though the glass transition temperature of the forming polymer increases during their interaction, since no diffusion of the groups is necessary to bring them into contact with each other. Consequently, in such molecules, conversion rates of 90%, or above, are generally attainable. Furthermore, since the functional groups on the ends of the side chains extending from individual molecules are contained in separate reactive structures or layers, cyclization does not present a problem.
Surprisingly, the monomers of the invention undergo little shrinkage during the process of polymerization, compared to ordinary polymers. Thus the resulting polymers avoid the strains resulting from shrinkage commonly experienced in typical polymers. Such avoidance makes the inventive polymers extremely useful as "potting" compounds, for instance.
While as previously described, difunctional mesogens have been previously prepared, the result has been the production of highly crystalline, brittle materials of limited usefulness. Surprisingly, it has been found that the introduction of linked "spacer" atoms between the reactive end groups, and the mesogens, provides a flexibility which results in "tough" non-brittle molecules, useful in broad applications. Typically, such molecules will have a molecular weight of from about 300 to 700, although molecular weights greater or less than that number may also provide useful properties. The polymers so formed exhibit relatively high glass transition temperatures due to the fact that the central region of the molecules is cyclic, providing the necessary crystalline ordering, while the end or terminal part of the chains are inter-reacted, giving a relatively "tight" cross-linked network.
Since as is apparent from the preceding, the reactive ends of the molecules are concentrated into a small fraction of the material's molecular volume, and are in physical contact with each other, the reactive groups at the ends can interact readily to give high conversions. Consequently, there is no tendency for the polymerization to terminate as the result of reduced diffusion, and concurrent reduced contact of the reactive groups, as the glass transition temperature rises.
Furthermore, the proximity of the reactive groups with each other assures that the reaction can take place rapidly, since little or no molecular motion is needed for group interaction.
While it has been found that spacer groups are required in order to avoid the crystalline brittleness described, when the side chains become too long, undesirably soft materials are produced. Monovinyl liquid crystal monomers and polymers extensively studied in some laboratories are, therefore, inappropriate for uses where mechanical strength is a desirable characteristic.
A variety of mesogen materials may be used, such as cyclic compounds and their various derivatives. In general, mesogens will be those of the standard liquid crystal types, for example, those of the general formula ##STR1## where "x" is -, CH 2 CH 2 , CH 2 S, CH 2 O, ##STR2## or equivalent groups, where "n" is 0, 1, or 2, and where "Y" will generally be O, S, ##STR3## or their equivalent.
Examples of suitable mesogenic materials include spiro compounds; trans-cyclohexyl analogues; biphenyls, e.g. dioxy biphenyl; aromatic esters and diesters; 1, 2, bis (oxyphenyl) ethane; 4, 4' biphenol; methylstilbene; 4, 4'-dihydroxy methyl stilbene; and terphenyl, whether the preceding are substituted or unsubstituted, as well as other mesogens of the types known to the art. It is preferable that no more than about three such mesogen groups be contained in the monomers of the invention, however, in order to avoid an undesirably high melting temperature and degree of crystallinity. By suitably adjusting the length and nature of the side chains, and that of the mesogen "core", the liquid crystalline temperature range of the monomers of the invention may be suitably adjusted. By making such adjustments, for instance, it has been found possible to synthesize liquid crystalline materials with a range of from about 10° to 90° C.
Various spacer groups which have been found useful for the purposes of introducing the linked spacer atoms of the invention, including spacer groups such as poly(oxyethylene) groups, --CH 2 --CH 2 O--; poly(methylene) groups, --CH 2 --, as well as equivalent groups. Generally, it has been found desirable to employ from at least 1 to about 11 spacer atoms derived from such groups between each of the functional terminal, or end groups, and the mesogen groups, a maximum of about 18 being necessary to avoid undesirable properties.
In preferred embodiments of the invention, where the polymerizable, functional group is an acrylic or methacrylic ester, and the mesogen is a bicyclic compound with oxygen linkages such as, for instance, ##STR4## the number of spacer atoms will usually be 2, 3, 6 or 11. Where the functional group is an epoxy group and the mesogen is ##STR5## "n" will typically be 1 or 4. In instances where the polymerizable group is a vinyl ether, "n" will often be 2, and where the group is a vinyl group, "n" will usually be from 2 to about 18.
It has also been found possible to lower the true melting point of the monomers, sometimes desirable, by introducing a degree of asymmetry in the monomers, for example, by putting a substituent, for instance, F, Cl, CN or CH 3 on a cyclic group, or on the side chains.
A variety of reactive groups can be incorporated at the ends of the monomers, for example, vinyl groups comprising compounds such as acrylate esters, methacrylate esters, and others, including the vinyl ethers and esters. Amino groups, including amino ethyl or amino propyl groups are also useful, as are epoxy groups, which may be reacted by means of amine curing, or otherwise. The use of additional reactive groups of the types well known in the art is also possible.
Polymerization of the ordered systems may be accomplished by any of the standard polymerization techniques employed in the art, including the use of thermal energy; free radical initiators together with promoters, for instance, peroxides and azo initiators; through the use of thermal initiators or photo initiators, for example 1-hydroxycyclohexyl phenyl ketone, in conjunction with exposure to ultraviolet light; and in the case of epoxy groups, amines, including compounds such as o-phenylene diamine, diethylenetriamine, and others may be used.
Generally, it has been found desirable to control the temperature of polymerization within, or slightly above the liquid crystalline range of the monomer being employed. In the latter regard, while the polymerization is preferably carried out within the liquid crystalline temperature range, i.e., below the clearing temperature of the monomers, when the temperature is raised somewhat above that temperature, semiorganized polymers are still obtainable. Consequently, the relative degree of crystallinity of the polymer, and therefore, its physical characteristics can be controlled by controlling the polymerization temperature, an empirical relationship easily determined through routine experimentation. While the polymerizations are normally run within the liquid crystalline temperature range, mesomorphic-type polymers can be obtained even when the temperature is increased to the point where polymerizations are carried out in the isotropic region; however, as previously explained, the polymerization temperature range will seldom be much above the clearing point of the liquid crystalline monomers, usually no more than about 50° above such point. Monomeric materials polymerized in the liquid crystal phase show particularly strong birefringence; however, even monomers polymerized in the isotropic phase exhibit some liquid crystalline organization, especially in the case of the acrylate polymers. Furthermore, the polymers produced are substantially completely cross-linked.
In instances where particularly highly ordered systems are required, it is believed that monomers of the invention exhibiting a high degree of anisotropy can be ordered, or "poled", by exposure to an electrical or magnetic field during the polymerization process, thereby producing even more highly ordered polymers.
Polymers of the invention exhibit moduli over a broad range, for example, from about 50,000 psi to 300,000 psi, depending upon the nature of the variables selected, including such things as the number of linking atoms in the spacer portions of the monomer molecules. Likewise, polymers having a wide range of glass transition temperatures may be prepared, for instance, from about 50° C. to about 180° C.
In instances where the dielectric constant at room temperature is low, the materials are useful in applications such as electrical "potting" compounds, in which low dielectric constants are desirable.
The polymers of the invention are particularly useful in the fabrication of composite matrices utilizing continuous or staple fibers such as glass fibers, graphite fibers, and the like.
While not intended to be limiting in nature, the following examples are illustrative of the invention.
MONOMER PREPARATION
A variety of difunctional monomers of the invention are prepared and polymerized as follows. The monomer synthesis involves preparation of the appropriate alcohol and its subsequent conversion, for example, into an ester by reaction with the appropriate acryloyl chloride compound.
PREPARATION OF 4,4'-DIOXYBIPHENYL ALCOHOLS
In a typical preparation, a mixture of biphenol (9.3 g, 0.050 mole), potassium hydroxide (7.45 g, 0.133 mole), 3-bromopropanol (27.8 g, 0.200 mole) (for the preparation with 6-chlorohexanol, 0.120 mole of potassium iodide is also added) is added in 200 ml of 95% ethanol. The solution is stirred at its reflux temperature for 30 hours. After the distillation of 120 ml of ethanol, 300 ml of 1% (by weight) sodium hydroxide solution is added, and the mixture is stirred for an additional 20 minutes more. The resulting precipitate is filtered, washed with water and dried under vacuum. The product is recrystallized from dioxane to yield 13.99 g (93%) of white crystals. Characterization for a variety of compounds thus prepared are presented in Table 1, below, in which B stands for the 4, 4' dioxybiphenyl mesogen, while the number represents the methylene units separating the biphenyl mesogen from the OH group.
TABLE 1__________________________________________________________________________Characterization of Typical Biphenyl AlcoholsBiphenylalcohols m.p. (°C.).sup.a 200 MH.sub.z .sup.1 H-NMR (DMSO-d.sub.6, σ,__________________________________________________________________________ ppm)B3OH 200 1.88 (m, 4H --C .sub.-- H.sub.2 --); 3.58 (t, 4H O--C .sub.-- .sub.2 --); 4.08 (t, 4H ph--O--C .sub.-- H.sub.2); 4.59 (t, 2H --O .sub.-- H--); 7.01 to 7.51 (8 aromatic protons).B6OH 97.sup.b 1.44 to 1.76 (m, 16H --(C .sub.-- H.sub.2).sub.4); and 178 3.42 (t, 4H, O--C .sub.-- H.sub.2 --); 4.02 (t, 4H, ph--O--C .sub.-- H.sub.2 --); 4.18 (t, 2H, --O--H); 7.0 to 7.49 (8 aromatic protons).B11OH 161 1.29 to 1.74 (m, 36H, --(C .sub.-- H.sub.2).sub.9 --; 3.20 (t, 2H, --O--H); 3.40 (t, 4H, O--C .sub.-- H.sub.2 --); 4.01 (t, 4H, ph--O--C .sub.-- H.sub.2 --); 6.99 to 7.48 (8 aromatic protons).__________________________________________________________________________ .sup.a Melting points were determined by DSC using 20° C./min heating rate. .sup.b B6OH has a melting point of 97° C. and a clearing point of 178° C.
PREPARATION OF 4,4'-DIOXYPHENYL METHACRYLATE AND ACRYLATE ESTERS
All the methacrylate esters and acrylate esters are synthesized by the esterification of the corresponding alcohol, with methacryloyl chloride or acryloyl chloride, as the case might be.
SYNTHESIS
Typical syntheses are illustrated in the following.
In a dry three-neck flask equipped with a thermometer, a pressure-equilibrated dropping funnel, and a reflux condenser (top fitted with a CaCl 2 drying tube), a mixture of B30H, (3.02 g, 0.0100 mole), phenothiazine (20mg, 0.00010 mole) and 200 ml of fresh dichloroethane is heated to reflux. Acryloyl chloride (2.75 g, 0.0300 mole) is added dropwise over a period of one hour. After the addition is complete, the mixture is refluxed for 3 more hours (5 hours for methacrylation). The cooled solution is washed with 5% sodium bicarbonate solution three times, once with water, and is then evaporated to dryness. Further purification is carried out by column chromatography using acidic silica gel as the stationary phase, and mixed solvents as the eluent, using standard techniques. After the solvent is evaporated in a rotovapor, the obtained acrylate ester monomer is recrystallized very slowly from methanol (from ethanol in the case of monomers with 11 methylene groups) to yield 2.71 g (66%) of product in the form of particles exhibiting the appearance of "flat flakes".
In a somewhat different synthesis, used for the preparation of methacrylate esters, in a dry round-bottom flask equipped with a pressureequilibrated dropping funnel, top fitted with a calcium chloride drying tube, B60H (3.86 g, 0.0100 mole) and phenothiazine (20 mg, 0.00010 mole) are dissolved in 380 ml of dry pyridine at room temperature. Methacryloyl chloride (2.53 g, 0.0240 mole) is added dropwise over a period of one hour. After the addition is complete, the mixture is stirred for 36 hours. The resulting mixture is then poured into dilute sulfuric acid solution containing crushed ice. The precipitate is collected by centrifugation and dried at room temperature. Further purification is carried out by column chromatography and recrystallization as described in the preceding synthesis. The yield is 3.76 g, (72%) of product having the physical appearance of white needles.
Analyses for representative monomers are listed in the following Table 2, in which A stands for acrylate and M for methacrylate, and the number again represents the methylene units or groups separating the mesogen from the A or M, as the case may be.
TABLE 2______________________________________Physical Properties and Analysis ofTypical Monomers synthesizedMonomer Crystal Yield Carbon (%) Hydrogen (%)type form (%) calc. found calc. found______________________________________B3M flat flakes 61 71.21 70.70 6.90 6.77B3A flat flakes 66 70.23 70.17 6.38 6.41B6M flat flakes 63 73.53 73.24 8.10 8.22B6A flat flakes 71 72.85 72.96 7.74 7.84B11M flat flakes 65 76.09 75.91 9.43 9.44B11A flat flakes 63 75.67 75.34 9.21 9.35______________________________________
POLYMERIZATION
Samples of the monomers are polymerized by melting the material on a clean glass slide and allowing the isotropic liquid to run under a coverslip by capillary action. While various polymerization techniques are employed as described in the following, the monomers, including those of the vinyl ether and epoxy types, can also be polymerized cationically with either photo, or thermal initiators.
PHOTOPOLYMERIZATION
The monomer of interest is mixed with 0.1 to 3%, by weight, of a photoinitiator, Irgacure 184, and 0.01% to 0.05% of di-t-butyl phenol in chloroform. The solution is dried by using a Rotovapor, and then further dried overnight in a vacuum oven. The fine monomer powder is placed between two glass plates previously treated with 0.1%, by weight, of trimethyl chlorosilane in chloroform and heated at about 100° C. to 110° C. for 30 minutes. A polymer film spacer having a thickness of about 0.2 to 0.4 mm is used to separate the plates. The monomer so prepared is then heated to its melting temperature in a vacuum oven to remove entrapped air, and cooled slowly in an oven after the vacuum is relieved. The monomer film may thereafter be UV-cured in a Q-UV chamber, or in a heating oven, using a General Electric J3 Sunlamp as the UV radiation source. The use of higher intensity, commercial-type UV lamps accelerates curing times greatly.
The following Table 4 lists typical treatment times and temperatures.
TABLE 4______________________________________ Reaction Chamber,Monomer Q-UV, °C. (time) Oven, °C. (time)______________________________________B2A 55 (3 days); 60 (5 days), 102 (30 hrs) 70 (3 days); 72 (3 days)B3A 68 (24 hrs); 72 (10 hrs) 85 (10 hrs)B6A 68 (24 hrs)B11A 45 (24 hrs); 72 (10 hrs) 85 (10 hrs)B3M 70 (24 hrs) 100 (5 hrs)______________________________________
POLYMERIZATION IN ELECTRICAL FIELD
In a subsequent experiment, photopolymerization is conducted in an electrical field by placing monomer powder, prepared as in the preceding example, between two conductive glass plates, previously surface treated with 0.1% of trimethyl chlorosilane in chloroform before use. A polymer spacer, polyethylene terephthalate having a thickness of about 0.2 to 0.4 mm is used to control the thickness of the sample. After the monomer is melted in a vacuum oven, a direct current electrical field of 10 to 40 volts is applied to the conductive glass plates. Two techniques are used, in a first, the sample is slowly cooled in the oven under normal atmospheric pressure, and is then UV-cured in the electrical field in a Q-UV chamber at a controlled temperature. In a second technique, the sample is cooled slowly to 60° C., and then UV-cured in the oven with a J3 Sunlamp as the UV radiation source. The temperature of the chamber is controlled by circulating heated air through the oven at a temperature of between 55° C. to 60° C.
The following Table 5 describes typical field strengths, temperatures and polymerization times.
TABLE 5______________________________________ TemperatureMonomer Electric Field °C. Polymerization Time______________________________________First ProcedureB2A 40 V 55 4 daysB2A 10 V 55 3 daysB2A 40 V 70 3 daysSecond ProcedureB2A 20 V 55/60 5 hours______________________________________
THERMOPOLYMERIZATION
In a further experiment, a thermopolymerization technique is used. In this procedure, the pure monomer is placed between two glass plates with a polyethylene terphthalate spacer having a thickness of about 0.2 to 0.4 mm. The sample is then heated to its melting temperature in a vacuum oven at about 100° C. The vacuum is thereafter relieved, and the temperature is raised to about 150° C. for 24 hours. The sample is then slowly cooled to room temperature.
Representative relationships between typical polymers prepared by the process of the invention, illustrating polymerization temperatures relative to the polymers' glass transition temperatures, are shown in the following Table 6.
TABLE 6______________________________________Polymer Polymerization Temp. Tg (1 Hz)______________________________________B2A 50-73° C. 58° C.B3A 60-75° C. (liquid crystalline) 185° C.B3A 85-100° C. (isotropic) 155° C.B3M 70° C. (liquid crystalline) 175° C.B3M 100° C. (isotropic) 155° C.B6A 68° C. 100° C.B11A 20-100° C. 55° C.______________________________________
The following Table 7 describes typical thermal polymerization temperatures and reaction times.
TABLE 7______________________________________Monomer Temperature °C. Time (hours)______________________________________ B2A 150 24B11A 150 24______________________________________
PREPARATION OF 4, 4' DIOXYMETHYLSTILBENE ALCOHOLS
In a still further experiment, methylstilbene alcohols are prepared using the procedures previously described for the preparation of the 4, 4'-dioxybiphenyl alcohols.
Characterization of the alcohols produced is set out in Table 8, below, in which S represents methyl stilbene.
TABLE 8______________________________________Characterization of Typical Biphenyl Alcohols by .sup.1 H-NMRBiphenyl 200 MHz .sup.1 H-NMRalcohol m.p. (°C.) (DMSO-D.sub. 6, δ, ppm)______________________________________S30H 157 ##STR6## ##STR7##S60H 69.sup.b ##STR8## and ##STR9## 132 ##STR10##S110H 157 ##STR11## ##STR12## ##STR13##______________________________________ .sup.a M.p. were determined by DSC using 20° C. min. heating rate. .sup.b S60H has a m.p. of 69° C. and a clearing point of 132° C.
PREPARATION OF 4, 4'-DIOXYMETHYLSTILBENE METHACRYLATE AND ACRYLATE ESTERS
The procedure for preparation of the esters is substantially the same as that previously described in connection with the 4, 4'-dioxyphenyl methacrylate and acrylate esters. Element analyses for the monomers thus formed are listed in Table 9. For reference, S stands for methyl stilbene, while the number indicates the number of CH 2 groups in the spacer; A indicates acrylates, and M stands for methacrylate.
TABLE 9__________________________________________________________________________Physical Properties and Analysis of Typical Monomers SynthesizedMonomer Crystal Yield Carbon % Hydrogen %type form (%) calc. experimental calc. experimental__________________________________________________________________________S3M flat flakes 58 72.78 72.53 7.16 7.20S3A white powder 65 71.98 71.89 6.71 6.75S6M flat flakes 67 74.70 74.98 8.24 8.05S6A flat flakes 65 74.13 73.96 7.92 7.97S11M flat flakes 62 76.88 77.02 9.46 9.53S11A flat flakes 70 76.52 76.83 9.26 9.06__________________________________________________________________________
For the synthesis of both methacrylate and acrylate esters, the following procedure is used.
In a dry round-bottomed flask equipped with a pressureequilibrated dropping funnel, top fitted with a calcium chloride drying tube, acryloyl chloride (1.10 g, 0.0120 mole) is added dropwise over a period of one hour to a stirred, ice-cooled solution of S60H (2.13 g, 0.00500 mole), anhydrous triethylamine (0.62 g, 0.0110 mole), and 200 ml fresh distilled THF. The reaction mixture is warmed slowly to room temperature, and stirred overnight (30 hours for methacrylation). The reaction mixture is filtered and evaporated to dryness. Further purification by column chromatography and recrystallization is similar to that previously described. The procedure yields 2.01 g (75%) of flat flakes.
Polymerization is subsequently carried out, using techniques similar to those described in the preceding.
POLYMERIZATION OF MIXED ACRYLATES AND METHACRYLATES
In a still further experiment, in order to broaden the liquid crystal range, acrylates are mixed with methacrylates having corresponding numbers of methylene groups. Mixtures of S3M with S3A are thus prepared.
The stilbene-type monomers are photopolymerized at different temperatures in the crystalline phase, the mesophase, as well as in the isotropic phase. The percentage polymerization obtained is determined by measuring the weight of the polymer before and after extraction with chloroform. The portion dissolving is found to be essentially pure monomer, as determined by gel permeation chromatography.
Details of the polymerizations are described in the following Table 10.
TABLE 10__________________________________________________________________________Typical Conditions and Percentages of PolymerizationPolymerization in Liquid Crystalline Polymerization inand Crystalline Phase Isotropic PhasePolymerTemp Time Conversion Temp Time Conversiontype (°C.) (hour) (%) (°C.) (hour) (%)__________________________________________________________________________PS3M 22 60 .sup.˜ 100 65 3 .sup.˜ 100PS3A 22 60 .sup.˜ 100 49 3 .sup.˜ 100-2.sup.a 120 .sup.˜ 100 18.sup.a 90 .sup.˜ 100 18 90 .sup.˜ 100 36.5.sup.a 72 .sup.˜ 100PS6M 22 60 .sup.˜ 100 49 3 .sup.˜ 100PS6A 22 60 .sup.˜ 100 65 3 .sup.˜ 100 60 5 .sup.˜ 100PS11M 22 60 .sup.˜ 100 80 3 .sup.˜ 100PS11A 22 60 .sup.˜ 100 80 3 .sup.˜ 100__________________________________________________________________________ .sup.a quenched in dry ice, then raised to the temperature desired.
The polymerization of monomers with epoxy reactive groups is examined in the following.
PREPARATION OF 4, 4'-DI(5-HEXENYLOXY)-5-BIPHENYL
Freshly cut sodium (0.190 g, 8.34×10 -3 mole) is dissolved in 20 ml of absolute ethyl alcohol. After the sodium is completely dissolved 4, 4'-biphenyl (0.776 g, 4.97×10 -3 mole) is added simultaneously. The ethyl alcohol is then removed using a rotovapor to form the sodium salt of 4, 4'-biphenyl. N-methyl-2-pyrrolidinone (2.0 mL) is thereafter added to the mixture. When the sodium salt has completely dissolved, 6-chloro-1-hexene (3×4.17×10 -3 mole) is added to the reaction mixture. The reaction is stirred at 110° C. under a nitrogen atmosphere overnight, cooled, and poured into water. The resulting precipitate is filtered, washed with a dilute aqueous solution of sodium hydroxide, with water, and then dried in a vacuum. The product is recrystallized from methanol and chloroform to yield white crystals, which are found to have a melting point of 51.2° proceeding from the crystalline to the smectic phases, and 119.5° C. going from the smectic to the isotropic phase.
EPOXIDATION REACTION
The 4, 4'-di(5-hexenyloxy)-5-biphenyl prepared according to the preceding reaction is epoxidized by mixing (1.75 g, 5×10 -3 mmol) with metachloroperoxybenzoic acid (1.72 g, 1×10 -2 mmol) and sodium bicarbonate (0.84 g, 1×10 -2 mmol) in 20 mL of perchloroethylene, and stirring the mixture at 5° C. for 15 hours. The reaction mixture is washed several times with a saturated solution of sodium sulfite, followed by water washing, and then drying. The methylene chloride is evaporated under vacuum to give B4E in which the B again represents the 4, 4' dioxybiphenyl mesogen, while the number represents the methylene units separating the mesogen from the terminal epoxy groups. The product is crystallized from methanol to give shiny white crystals (1.85 g, 99% yield).
In a subsequent experiment, B1E is prepared by dissolving freshly cut sodium (0.190 g, 8.34×10 -3 mole) in 20 mL of absolute ethyl alcohol. After the sodium is completely dissolved, 4, 4'-biphenyl (0.772 g, 4.17×10 -3 mole) is added. The ethyl alcohol is then removed using a rotovapor to form the sodium salt of 4, 4'-biphenyl, and N-methyl-2-pyrrolidinone (20 mL) is added to the mixture. When the sodium salt has completely dissolved, epichlorohydrin (1.5 g, 16.68×10 -3 mmol) is added to the reaction mixture. The reaction is stirred for 3 hours at 100° C. under nitrogen atmosphere, cooled, and poured into water. The resulting precipitate is filtered, washed with water, and dried in a vacuum. The product is recrystallized from methanol and chloroform to give 1.2 g (80%) yield of white crystals.
POLYMERIZATION
The epoxidized compounds described are subsequently polymerized by mixing equimolar amounts of the epoxidized compound selected with p-phenylenediamine, in a chloroform solvent. The solution is evaporated to dryness and the solids thus obtained spread across a glass slide protected with a cover glass. The slide is thereafter heated for from about 10 to 15 hours at 100° C. on a Mettler hot stage. The initial birefringent areas of the material remain unchanged throughout the heating process. After heating, the temperature of the resin can be raised to 220° C., the temperature limit of the stage, with no change in structure being observed. Since B1E melts at 157° C., while B4E melts at 110° C., the retention of birefringence at 220° C. indicates that the materials have polymerized with cross-linking. Similar results are obtained when the molar ratio of the epoxy compound is twice that of the amine compound, which latter may be p-phenylenediamine, diethyenetriamine, or equivalent amines.
While in accordance with the patent statutes, a preferred embodiment and best mode has been presented, the scope of the invention is not limited thereto, but rather is measured by the scope of the attached claims.
|
Polymeric compositions exhibiting superior physical properties, useful in the fabrication of composites and other applications, are prepared by the polymerization of thermotropic, monomeric materials having orderable molecular structures. The monomers comprise molecules containing mesogen groups with side chains on either end thereof terminated with reactive groups, the reactive groups being separated from the mesogens by spacer atoms. The monomers are polymerized in their crystalline or liquid crystalline state, or under conditions which assure that at least part of the monomeric molecules are in an ordered state. The reactive groups which are consequently in proximity with each other, are thereby capable of interaction without molecular diffusion, allowing substantially complete polymerizations to be achieved despite the increasing conversion and glass transition temperature of the polymers being formed.
| 2
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional application No. 60/445,274, filed Feb. 5, 2003; the disclosures of which are incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to nucleic acid amplification. More specifically, the present invention relates to the use of terminal-phosphate labeled nucleotides in nucleic acid amplification.
BACKGROUND OF THE INVENTION
[0003] Methods are known for detecting specific nucleic acids or analytes in a sample with high specificity and sensitivity. Such methods generally require first amplifying nucleic acid sequence based on the presence of a specific target sequence or analyte. Following amplification, the amplified sequences are detected and quantified. Conventional detection systems for nucleic acids include detection of fluorescent labels, fluorescent enzyme-linked detection systems, antibody-mediated label detection, and detection of radioactive labels.
[0004] One disadvantage of these methods is that the labeled product not only requires some type of separation from the labeled starting materials but also, since the label is attached to the product, it is different than the natural product to be identified. It would, therefore, be of benefit to use methods and substrates that form unmodified product and at the same time generate a signal characteristic of the reaction taking place. It is of further benefit if the signal generated doesn't require separation from the starting materials but even if a separation is required the benefits of generating unmodified product in many cases are overwhelming.
[0005] Terminal-phosphate labeled nucleotides provide the above benefits. For example, incorporation of gamma- or delta-labeled nucleotides into DNA or RNA by nucleic acid polymerases results in the production of unmodified DNA or RNA and at the same time the labeled pyrophosphate generated can be used to detect, characterize and/or quantify the target. If these could be used in amplification reactions not only would they provide useful tools for detection and quantification of target sequence, but the amplified product, which is exact copies of the target sequence without modifications can be used in further studies.
[0006] DNA amplification by a number of amplification methods is performed at high temperatures. For example, in PCR, repeated cycles of denaturation at 95° C., annealing around 60° C. and extension around 70° C. causes significant breakdown of the dNTP's. This may significantly affect the yield of product in later cycles. Other amplification methods such as RCA and NASBA, although isothermal, also are conducted at higher temperatures. In case of NASBA, which is performed at 41° C., the stability of nucleotides may not be very critical, however in RCA which may be conducted at higher temperature depending upon the polymerase used and the complexity of sequence to be amplified, stability of nucleotides can be an issue under these conditions. If breakdown of the terminal-phosphate labeled nucleotides were to occur, the amount of background generated would overwhelm any signal directly related to the amplification process. It is therefore desirable to have nucleotides that can survive this repeated cycling of temperature or prolonged heating at a constant yet high temperature and hence continue to give high product yields and low background even in later cycles of amplification and possibly cut down the number of cycles/time required to achieve desirable amplification. Additionally, gamma-phosphate labeled nucleotides are extremely poor substrates for polymerase under the conditions normally used for nucleic acid synthesis and amplification. Synthesis of long stretches of nucleic acids (several hundred to several thousand bases long) would require hours if not days per cycle. Harding et. al. (WO 0244425 A2) describe the use of aminonaphthalenesulfonate-gamma-amido-dATP for DNA synthesis at high temperature. However, according to the inventors, in this case the synthesis only proceeds after the aminonaphthalenesulfonate hydrolyzes off the nucleotide and it is dATP that is used by the polymerase to form DNA. This of course is useless for detection or quantification of target sequence as the dye generated is independent of DNA synthesis.
[0007] A number of real time assays have been developed for quantification of DNA. Most of these can be classified into two categories. First category which is relatively easy to use involves the use of intercalating dyes, which have enhanced fluorescence upon intercalation. A number of nucleic acid stains such as ethidium bromide, SYBR Green® dyes, PicoGreen®, YOYO®, TOTO® or analogs have been developed as intercalators for real time assays. These, however, generate significant background signal partially due to intercalation between primer dimers and partially because they are fluorescent, albeit weakly, even when they are not intercalated.
[0008] The other category of real time assay is based on the use of fluorescence resonance energy transfer between a dye and a quencher. A number of these assays have been developed using FRET probes and or primers, such as Taqman, MGB Eclipse™, Scorpion primers, Molecular Beacons, sunrise primers, to name a few. These probes/primers are quenched by energy transfer until the amplification takes place and the quencher is physically separated from the dye or cleaved. Sensitivity of these assays depends greatly on the probe design and require a lot of optimization. In addition even with the best optimized probe, complete quenching is not achieved. So these assays can only provide a few fold enhancement in signal upon amplification and in the initial cycles background signal is much higher than the true signal.
[0009] It would be of benefit, therefore, to develop methods of amplification using terminal-phosphate labeled nucleoside polyphosphates where the amplification can be performed in reasonable time (similar to unmodified dNTP's) and the amount of label generated is proportional to the product formed. It is further desirable to have a real time assay, where the amount of label generated can be independently detected without interference of signal from the terminal-phosphate labeled nucleotide. It would be desirable to have a real time assay where the label is completely dark until the amplification proceeds.
SUMMARY OF THE INVENTION
[0010] The present invention provides methods of using terminal-phosphate labeled nucleotides (also referred to as terminal-phosphate labeled nucleoside polyphosphates) in nucleic acid amplification. Methods are also provided for the detection and quantification of a target sequence by selective amplification. Further provided are methods for the real-time detection and quantification of a target sequence during amplification.
[0011] The present invention provides for a method of detecting the presence of a nucleic acid sequence including the steps of: a) conducting a nucleic acid amplification which includes the reaction of a terminal-phosphate-labeled nucleotide, which reaction results in the production of labeled polyphosphate; b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; and c) detecting the presence of the detectable species. A definition of phosphatase in the current invention includes any enzyme which cleaves phosphate mono esters, phosphate thioester, phosphoramidate, polyphosphates and nucleotides to release inorganic phosphate. In the context of the present invention, this enzyme does not cleave a terminally labeled nucleoside phosphate (i.e. the terminal-phosphate-labeled nucleotide is substantially non-reactive to phosphatase). The phosphatase definition herein provided specifically includes, but is not limited to, alkaline phosphatase (EC 3.1.3.1) and acid phosphatase (EC 3.1.3.2). The definition of a nucleotide in the current invention includes a natural or modified nucleoside phosphate.
[0012] The present invention provides for a method of detecting the presence of a nucleic acid sequence including the steps of: a) conducting a nucleic acid amplification reaction in the presence of a manganese salt, wherein the reaction includes the reaction of a terminal-phosphate-labeled nucleotide, which reaction results in the production of labeled polyphosphate; b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; and c) detecting the presence of the detectable species.
[0013] The invention further provides for a method of detecting the presence of a DNA sequence including the steps of: a) conducting a DNA amplification reaction in the presence of a terminal-phosphate-labeled nucleotide, which reaction results in the production of a labeled polyphosphate; b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; and c) detecting the presence of the detectable species.
[0014] The invention further provides for a method of detecting the presence of a DNA sequence including the steps of: a) conducting a DNA amplification reaction in the presence of a terminal-phosphate-labeled nucleotide and a manganese salt, which reaction results in the production of a labeled polyphosphate; b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; and c) detecting the presence of the detectable species.
[0015] The invention further provides for a method of detecting the presence of a DNA sequence including the steps of: a) conducting a DNA amplification reaction in the presence of a terminal-phosphate-labeled nucleotide, which reaction results in the production of a labeled polyphosphate; b) detecting the presence of the labeled polyphosphate.
[0016] Also provided is a method of detecting the presence of a nucleic acid sequence comprising the steps of: (a) conducting a nucleic acid amplification reaction in the presence of at least one terminal-phosphate-labeled nucleotide having four or more phosphate groups in the polyphosphate chain, which reaction results in the production of a labeled polyphosphate; and (b) detecting the labeled polyphosphate.
[0017] Also provided is a method of detecting the presence of a nucleic acid sequence comprising the steps of: (a) conducting a nucleic acid amplification reaction in the presence of a manganese salt and at least one terminal-phosphate-labeled nucleoside polyphosphate, which reaction results in the production of a labeled polyphosphate; and (b) detecting the labeled polyphosphate.
[0018] Also provided is a method of detecting the presence of a nucleic acid sequence comprising the steps of: (a) conducting a nucleic acid amplification reaction in the presence of a manganese salt and at least one terminal-phosphate-labeled nucleotide having four or more phosphate groups in the polyphosphate chain, which reaction results in the production of a labeled polyphosphate; and (b) detecting the labeled polyphosphate.
[0019] In addition, the invention relates to a method of detecting the presence of a nucleic acid sequence comprising the steps of: (a) conducting a nucleic acid amplification reaction in the presence of at least one terminal-phosphate-labeled nucleotide having four or more phosphate groups in the polyphosphate chain, which reaction results in the production of a labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; and (c) detecting the presence of the detectable species.
[0020] A further aspect of the present invention relates to a method of quantifying a nucleic acid including the steps of: (a) conducting a nucleic acid amplification reaction, wherein the reaction includes a terminal-phosphate-labeled nucleotide, which reaction results in production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable by-product species in an amount substantially proportional to the amount of nucleic acid; (c) measuring the detectable species; and (d) comparing the measurements using known standards to determine the quantity of nucleic acid.
[0021] In addition, the invention relates to a method of detecting the presence of a nucleic acid sequence comprising the steps of: (a) conducting a nucleic acid amplification reaction in the presence of a manganese salt and at least one terminal-phosphate-labeled nucleotide having four or more phosphate groups in the polyphosphate chain, which reaction results in the production of a labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; and (c) detecting the presence of the detectable species.
[0022] A further aspect of the present invention relates to a method of quantifying a nucleic acid including the steps of: (a) conducting a nucleic acid amplification reaction in the presence of a manganese salt, wherein the reaction includes a terminal-phosphate-labeled nucleotide, which reaction results in production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable by-product species in an amount substantially proportional to the amount of nucleic acid; (c) measuring the detectable species; and (d) comparing the measurements using known standards to determine the quantity of nucleic acid.
[0023] The invention further relates to a method of quantifying a DNA sequence including the steps of: (a) conducting a DNA polymerase reaction in the presence of a manganese salt and a terminal-phosphate-labeled nucleotide, the reaction resulting in production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable by-product species in amounts substantially proportional to the amount of the DNA sequence; (c) measuring the detectable species; and (d) comparing the measurements using known standards to determine the quantity of DNA.
[0024] The invention further relates to a method of quantifying a DNA sequence including the steps of: (a) conducting a DNA amplification reaction in the presence of a manganese salt and a terminal-phosphate-labeled nucleotide, the reaction resulting in production of labeled polyphosphate in amounts substantially proportional to the amount of the DNA sequence; (b) measuring the labeled polyphosphate; and (c) comparing the measurements using known standards to determine the quantity of DNA.
[0025] Another aspect of the invention relates to a method for determining the identity of a single nucleotide in a nucleic acid sequence, which includes the steps of: (a) conducting a nucleic acid amplification reaction in the presence of at least one terminal phosphate-labeled nucleotide, an allele specific primer, which reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; (c) detecting the presence of the detectable species; and (d) identifying the nucleoside incorporated.
[0026] Another aspect of the invention relates to a method for determining the identity of a single nucleotide in a nucleic acid sequence, which includes the steps of:
[0027] (a) conducting a nucleic acid amplification reaction in the presence of at least one terminal phosphate-labeled nucleotide, an allele specific primer and a manganese salt, which reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; (c) detecting the presence of the detectable species; and (d) identifying the nucleoside incorporated.
[0028] Also provided is a method for determining the identify of a single nucleotide in a nucleic acid sequence including the following steps: (a) conducting a nucleic acid amplification reaction in the presence of at least one terminal-phosphate-labeled nucleotide having four or more phosphate groups in the polyphosphate chain, which reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; (c) detecting the presence of said detectable species; and (d) identifying the nucleoside incorporated.
[0029] Also provided is a method for determining the identify of a single nucleotide in a nucleic acid sequence including the following steps: (a) conducting a nucleic acid amplification reaction in the presence of a manganese salt and at least one terminal-phosphate-labeled nucleotide having four or more phosphate groups in the polyphosphate chain, which reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; (c) detecting the presence of said detectable species; and (d) identifying the nucleoside incorporated.
[0030] The present invention further provides a method of amplifying a nucleic acid sequence in the presence of a terminal-phosphate labeled nucleoside polyphosphate stabilizer such as polyol (glycerol, threitol, etc.), a polyether including cyclic polyethers, polyethylene glycol, organic or inorganic salts, such as ammonium sulfate, sodium sulfate, sodium molybdate, sodium tungstate, organic sulfonate, etc., in conjunction with a terminal-phosphate labeled nucleoside polyphosphate in the presence of a metal salt, such as manganese, magnesium, zinc, calcium or cobalt salts, to decrease the background signal generation in an enzymatic assay.
[0031] The present invention further includes a nucleic acid detection kit wherein the kit includes:
[0032] (a) at least one or more terminal-phosphate-labeled nucleotide according to Formula I:
[0033] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is a label containing a hydroxyl group, a sulfhydryl group, a haloalkyl group or an amino group suitable for forming a phosphate ester, a thioester, alkylphosphonate or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label and may contain a linker between P and L; and
[0034] (b) at least one nucleic acid polymerase.
[0035] The present invention further includes a nucleic acid quantification kit wherein the kit includes:
[0036] (a) at least one terminal-phosphate-labeled nucleotide according to Formula below:
[0037] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is an enzyme-activatable label containing a hydroxyl group, a sulfhydryl group, a haloalkyl group or an amino group suitable for forming a phosphate ester, a thioester, alkylphosphonate or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label and may contain a linker between P and L; and
[0038] (b) at least one nucleic acid polymerase.
[0039] The present invention further includes a nucleic acid detection or quantification kit wherein the kit includes:
[0040] (a) at least one terminal-phosphate-labeled nucleotide according to Formula below:
[0041] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is an enzyme-activatable label containing a hydroxyl group, a sulfhydryl group or an amino group suitable for forming a phosphate ester, a thioester or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label which preferably becomes independently detectable when the phosphate is removed;
[0042] (b) at least one nucleic acid polymerase;
[0043] (c) a phosphatase;
[0044] (d) a stabilizer; and
[0045] (e) a reaction buffer containing a manganese salt.
[0046] The present invention further includes a nucleic acid detection or quantification kit wherein the kit includes:
[0047] (a) at least one terminal-phosphate-labeled nucleotide according to Formula below:
[0048] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is an enzyme-activatable label containing a hydroxyl group, a sulfhydryl group or an amino group suitable for forming a phosphate ester, a thioester or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label which preferably becomes independently detectable when the phosphate is removed;
[0049] (b) at least one nucleic acid polymerase; and
[0050] (c) phosphatase.
BRIEF DESCRIPTION OF THE DRAWINGS
[0051] [0051]FIG. 1 is a gel showing PCR amplification of a target sequence using a terminal-phosphate labeled nucleoside polyphosphate with different polymerase.
[0052] [0052]FIG. 2 shows PCR amplification of pUCp53 DNA using terminal-phosphate labeled nucleoside polyphosphates with different labels or bases.
[0053] [0053]FIG. 3 shows PCR amplification of pUC18 DNA using terminal-phosphate labeled nucleoside polyphosphates with different labels or bases.
[0054] [0054]FIG. 4 shows stabilization of dT4P-DDAO with ammonium sulfate.
[0055] [0055]FIG. 5 shows stabilization of dT4P-DDAO with a variety of organic and inorganic salts.
[0056] [0056]FIG. 6 shows PCR amplification with terminal-phosphate labeled nucleoside polyphosphates in the presence of stabilizers.
[0057] [0057]FIG. 7 shows quantitative PCR results with terminal-phosphate labeled nucleoside polyphosphates on ABI 7900 instrument.
[0058] [0058]FIG. 8 shows PCR product produced during quantitative PCR using terminal-phosphate labeled nucleoside polyphosphate.
[0059] [0059]FIG. 9 shows linear amplification of chromosomal DNA using terminal-phosphate labeled nucleoside polyphosphates and Phi29 DNA polymerase.
[0060] [0060]FIG. 10 shows that the amount of product produced in the initial phase of amplification is directly proportional to the amount of input DNA.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0061] The term “nucleoside” as defined herein is a compound including a purine deazapurine, pyrimidine or modified base linked to a sugar or a sugar derivative.
[0062] The term “nucleotide” as used herein refers to a phosphate ester of a nucleoside, wherein the esterification site typically corresponds to the hydroxyl group attached to the C-5 position of the pentose sugar.
[0063] The term “oligonucleotide” includes linear oligomers of nucleotides or derivatives thereof, including deoxyribonucleosides, ribonucleosides, and the like. Throughout the specification, whenever an oligonucleotide is represented by a sequence of letters, the nucleotides are in the 5′→3′ order from left to right where A denotes deoxyadeno sine, C denotes deoxycytidine, G denotes deoxyguano sine, and T denotes thymidine, unless noted otherwise.
[0064] The term “primer” refers to a linear oligonucleotide that anneals in a specific way to a unique nucleic acid sequence and allows for amplification of that unique sequence.
[0065] The phrase “target nucleic acid sequence” and the like refers to a nucleic acid whose sequence identity, or ordering or location of nucleosides is determined by one or more of the methods of the present invention.
[0066] The present invention relates to methods of detecting a polynucleotide in a sample wherein an assay is used for monitoring RNA or DNA synthesis via nucleic acid polymerase activity. RNA and DNA polymerases synthesize oligonucleotides via transfer of a nucleoside monophosphate from a nucleoside triphosphate (NTP) or deoxynucleoside triphosphate (dNTP) to the 3′ hydroxyl of a growing oligonucleotide chain. The force which drives this reaction is the cleavage of an anhydride bond and the con-commitant formation of an inorganic pyrophosphate. The present invention utilizes the finding that structural modification of the terminal-phosphate of the nucleotide does not abolish its ability to function in the polymerase reaction. The oligonucleotide synthesis reaction involves direct changes only at the α- and β-phosphoryl groups of the nucleotide, allowing nucleotides with modifications at the terminal phosphate position to be valuable as substrates for nucleic acid polymerase reactions.
[0067] In certain embodiments, the polymerase is a DNA polymerase, such as DNA polymerase I, II, or III or DNA polymerase α, β, γ, or terminal deoxynucleotidyl transferase or telomerase. In other embodiments, suitable polymerases include, but are not limited to, a DNA dependent RNA polymerase, a primase, or an RNA dependant DNA polymerase (reverse transcriptase).
[0068] The methods provided by this invention utilize a nucleoside polyphosphate, such as a nucleoside polyphosphate, deoxynucleoside polyphosphate, with an electrochemical label, mass tag, or a colorimetric dye, chemiluminescent, or fluorescent label attached to the terminal-phosphate. When a nucleic acid polymerase uses this analogue as a substrate, a label would be present on the inorganic polyphosphate by-product of phosphoryl transfer. This label may be read directly or in preferable cases label is enzyme activatable and can be read after removal of phosphates. In latter case, cleavage of the polyphosphate product of phosphoryl transfer via phosphatase, leads to a detectable change in the label attached thereon. It is noted that while RNA and DNA polymerases are able to recognize nucleotides with modified terminal phosphoryl groups, the inventors have determined that this starting material is not a template for phosphatases. The scheme below shows some relevant molecules in the methods of this invention; nanely the terminal-phosphate-labeled nucleotide, the labeled polyphosphate by-product and the enzyme-activated label.
[0069] In the scheme above, n is 1 or greater, R1 is OH and R2 is H or OH; B is a nucleoside base or modified heterocyclic base; X is O, S, CH2 or NH; Y is O, S, or BH3; and L is a phosphatase activatable label which may be a chromogenic, fluorogenic, chemiluminescent molecule, mass tag or electrochemical tag. A mass tag is a small molecular weight moiety suitable for mass spectrometry that is readily distinguishable from other components due to a difference in mass. An electrochemical tag is an easily oxidizable or reducible species. It has been discovered that when n is 2 or greater, the nucleotides are significantly better substrates for polymerases than when n is 1. Therefore, in preferred embodiments, n is 2, 3 or 4; X and Y are O; B is a nucleoside base and L is a label which may be a chromogenic, fluorogenic or a chemiluminescent molecule.
[0070] In one embodiment of the method of detecting the presence of a nucleic acid sequence provided herein, the steps include (a) conducting a nucleic acid amplification reaction wherein the reaction includes at least one nucleotide which is substantially non-reactive to phosphatase in addition to one terminal-phosphate-labeled nucleotide wherein the polymerase reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase suitable to hydrolyze the phosphate ester and to produce a detectable species; and c) detecting the presence of a detectable species by suitable means. In this embodiment, the template used for the nucleic acid polymerase reaction may be a heteropolymeric or homopolymeric template. By terminal-phosphate-labeled nucleotide, it is meant throughout the specification that the labeled polyphosphate con-committantly released following incorporation of the nucleoside monophosphate into the growing nucleotide chain, may be read directly or if an enzyme-activatable label, it may be reacted with a phosphatase to produce a detectable species. Other nucleotides included in the reaction which are substantially non-reactive to phosphatase may also be, for example, blocked at the terminal-phosphate by a moiety which does not lead to the production of a detectable species by the method used for the detection of the detectable species produced from the labeled nucleotide. The nucleic acid for detection in this particular embodiment may include RNA, a natural or synthetic oligonucleotide, mitochondrial or chromosomal DNA.
[0071] In one embodiment of the method of detecting the presence of a nucleic acid sequence provided herein, the steps include (a) conducting a nucleic acid amplification reaction in the presence of a Mn salt wherein the reaction includes at least one nucleotide which is substantially non-reactive to phosphatase in addition to one terminal-phosphate-labeled nucleotide wherein the polymerase reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase suitable to hydrolyze the phosphate ester and to produce a detectable species; and c) detecting the presence of a detectable species by suitable means.
[0072] The invention further provides a method of detecting the presence of a DNA sequence including the steps of (a) conducting a DNA amplification reaction in the presence of a terminal-phosphate labeled nucleotide, which reaction results in the production of a labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; and (c) detecting the presence of said detectable species. The DNA sequence for detection may include DNA isolated from cells, chemically treated DNA such as bisulfite treated methylated DNA or DNA chemically or enzymatically synthesized according to methods known in the art. Such methods include PCR, and those described in DNA Structure Part A: Synthesis and Physical analysis of DNA, Lilley, D. M. J. and Dahlberg, J. E. (Eds.), Methods Enzymol., 211, Academic Press, Inc., New York (1992), which is herein incorporated by reference. The DNA sequence may further include chromosomal DNA and natural or synthetic oligonucleotides. The DNA may be either double- or single-stranded.
[0073] The invention further provides a method of detecting the presence of a DNA sequence including the steps of (a) conducting a DNA amplification reaction in the presence of a Mn salt and a terminal-phosphate labeled nucleotide, which reaction results in the production of a labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable species; and (c) detecting the presence of said detectable species.
[0074] The methods of the invention may further include the step of including one or more additional detection reagents in the polymerase reaction. The additional detection reagent may be capable of a response that is detectably different from the detectable species. For example, the additional detection reagent may be an antibody.
[0075] Suitable nucleotides for addition as substrates in the polymerase reaction include nucleoside polyphosphates, including, but not limited to, deoxyribonucleoside polyphosphates, ribonucleoside polyphosphates, and analogs thereof. Particularly desired are nucleotides containing 3, 4, or 5 phosphate groups in the polyphosphate chain, where the terminal phosphate is labeled.
[0076] It is noted that, it is within the contemplation of the present invention that the labeled polyphosphate by-product of phosphoryl transfer may be detected without the use of phosphatase treatment. For example, it is known that natural or modified nucleoside bases, particularly guanine, can cause quenching of fluorescent markers. Therefore, in a terminal-phosphate-labeled nucleotide, the label may be partially quenched by the base. Upon incorporation of the nucleoside monophosphate, the label of polyphosphate by-product may be detected due to its enhanced fluorescence. Alternatively, it is possible to physically separate the labeled polyphosphate product by chromatographic or other separation methods before identification by fluorescence, color, chemiluminescence, or electrochemical detection. In addition, mass spectrometry could be used to detect the products by mass difference.
[0077] The methods of the present invention may include conducting the polymerase reaction in the presence of at least one of DNA or RNA polymerase. Suitable nucleic acid polymerases may also include primases, telomerases, terminal deoxynucleotidyl transferases, and reverse transcriptases. A nucleic acid template may be required for the polymerase reaction to take place and may be added to the polymerase reaction solution. It is anticipated that all of the steps (a), (b) and (c) in the detection methods of the present invention could be run concurrently using a single, homogenous reaction mixture, as well as run sequentially.
[0078] Examples of amplification methods useful in the current invention include, but are not limited to, polymerase chain reaction (PCR), rolling circle amplification (RCA), strand displacement amplification (SDA), and nucleic acid sequence based amplification (NASBA). For e.g., wherein the target molecule is a nucleic acid polymer such as DNA, it may be detected by PCR incorporation of a gamma-phosphate labeled nucleotide base such as adenine, thymine, cytosine, guanine or other nitrogen heterocyclic bases into the DNA molecule. The polymerase chain reaction (PCR) method is described by Saiki et al in Science Vol. 239, page 487, 1988, Mullis et al in U.S. Pat. No. 4,683,195 and by Sambrook, J. et al. (Eds.), Molecular Cloning, second edition, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (1980), Ausubel, F. M. et al. (Eds.), Current Protocols in Molecular Biology, John Wiley & Sons, Inc., NY (1999), and Wu, R. (Ed.), Recombinant DNA Methodology II, Methods in Zumulogy, Academic Press, Inc., NY, (1995). Using PCR, the target nucleic acid for detection such as DNA is amplified by placing it directly into a reaction vessel containing the PCR reagents and appropriate primers. Typically, a primer is selected which is complimentary in sequence to at least a portion of the target nucleic acid.
[0079] It is noted that nucleic acid amplification reactions suitable for conducting step (a) of the methods of the present invention may further include various RCA methods of amplifying nucleic acid sequences. For example, those disclosed in U.S. Pat. No. 5,854,033 to Lizardi, Paul M., incorporated herein by reference, are useful. Polymerase reactions may further include the nucleic acid sequence based amplification (NASBA) wherein the system involves amplification of RNA, not DNA, and the amplification is iso-thermal, taking place at one temperature (41° C.). Amplification of target RNA by NASBA involves the coordinated activities of three enzymes: reverse transcriptase, RNAse H, and T7 RNA polymerase along with oligonucleotide primers directed toward the sample target RNA. These enzymes catalyze the exponential amplification of a target single-stranded RNA in four steps: extension, degradation, DNA synthesis and cyclic RNA amplification.
[0080] Methods of RT-PCR, RCA, and NASBA generally require that the original amount of target nucleic acid is indirectly measured by quantification of the amplification products. Amplification products are typically first separated from starting materials via electrophoresis on an agarose gel to confirm a successful amplification and are then quantified using any of the conventional detection systems for a nucleic acid such as detection of fluorescent labels, enzyme-linked detection systems, antibody-mediated label detection and detection of radioactive labels. In contrast, the present method eliminates the need to separate products of the polymerase reaction from starting materials before being able to detect these products. For example, in the present invention, a reporter molecule (fluorescent, chemiluminescent or a chromophore) or other useful molecule is attached to the nucleotide in such a way that it is undetectable under certain conditions when masked by the phosphate attachment. However, following the incorporation of the nucleotide into the growing oligonucleotide chain and phosphatase treatment of the reaction, the label is detectable under those conditions. For example, if the hydroxyl group on the side of the triple ring structure of 1,3-dichloro-9,9-dimethyl-acridine-2-one (DDAO) is attached to the terminal-phosphate position of the nucleotide, the DDAO does not fluoresce at 659 nm. Once the nucleoside monophosphate is incorporated into DNA, the other product, DDAO polyphosphate (which also does not fluoresce at 659 nm) is a substrate for phosphatase. Once de-phosphorylated to form DDAO, the dye moiety will become fluorescent at 659 nm and hence detectable. The specific analysis of the polyphosphate product can be carried out in the polymerase reaction solution, eliminating the need to separate reaction products from starting materials. This scheme allows for the detection and, optionally, quantification of nucleic acids formed during polymerase reactions using routine instrumentation such as spectrophotometers.
[0081] In the methods described above, the amplification reaction step may further include conducting the polymerase reaction in the presence of a phosphatase, which converts labeled polyphosphate by-product to the detectable label. As such, a convenient assay is established for detecting the presence of a nucleic acid sequence that allows for continuous monitoring of detectable species formation. This represents a homogeneous assay format in that it can be performed in a single tube.
[0082] One format of the assay methods described above may include, but is not limited to, conducting the amplification reaction in the presence of a single type of terminal-phosphate-labeled nucleotide capable of producing a detectable species. For example, one could use a dye-labeled ATP while the remaining three nucleotides have a moiety that is not a dye; said moiety makes these nucleotides non-reactive towards phosphatase. In this example, the said moieties are not detectable under the conditions used for detecting said dye.
[0083] In another assay format, the amplification reaction may be conducted in the presence of more than one type of terminal-phosphate-labeled nucleotide, each type capable of producing a uniquely detectable species. For example, the assay may include a first nucleotide (e.g., adenosine polyphosphate) that is associated with a first label which when liberated enzymatically from the inorganic polyphosphate by-product of phosphoryl transfer, emits light at a first wavelength and a second nucleotide (e.g., guanosine polyphosphate) associated with a second label that emits light at a second wavelength. Desirably, the first and second wavelength emissions have substantially little or no overlap. It is within the contemplation of the present invention that multiple simultaneous assays based on nucleotide sequence information can thereafter be derived based on the particular label released from the polyphosphate.
[0084] In one aspect of the methods of detecting the presence of a nucleic acid sequence described above, the terminal-phosphate-labeled nucleotide may be represented by the following structure:
[0085] wherein P=phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is an enzyme-activatable label containing a hydroxyl group, a sulfhydryl group or an amino group suitable for forming a phosphate ester, a thioester, or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label which preferably becomes independently detectable when the phosphate is removed.
[0086] In another aspect, L may also contain a haloalkyl group suitable for forming alkyl phosphonate. In this aspect, labeled phosphate or labeled polyphosphate is the detectable species.
[0087] In certain embodiments, the sugar moiety in Formula I may be selected from the following: ribosyl, 2′-deoxyribosyl, 2′-alkoxyribosyl, 2′-aminoribosyl, 2′-fluororibosyl, and other modified sugars with the proviso that such modification doesn't prevent further nucleic acid chain elongation. For example, 3′ position of the sugar must have a hydroxyl group so that incoming nucleoside monophosphate can attach to this position.
[0088] Moreover, in Formula I, the base may include uracil, thymine, cytosine, 5-methylcytosine, guanine, 7-deazaguanine, hypoxanthine, 7-deazahypoxanthine, adenine, 7-deazaadenine, 2,6-diaminopurine or analogs thereof.
[0089] The label attached at the terminal-phosphate position in the terminal-phosphate-labeled nucleotide may be selected from the group consisting of 1,2-dioxetane chemiluminescent compounds, fluorogenic dyes, chromogenic dyes, mass tags and electrochemical tags. This would allow the detectable species to be detectable by the presence of any one of color, fluorescence emission, chemiluminescence, mass change, electrochemical detection or a combination thereof.
[0090] In addition energy transfer dyes made by conjugating a donor dye and an acceptor dye are also useful in the current invention.
[0091] Examples of labels that may be attached to the terminal phosphate group either directly or through linkers are give in Tables 1-2 below. Some examples of terminal phosphate labeled nucleoside polyphosphates are shown in Table 3.
TABLE 1 Examples of detectable label moieties that become independently detectable after removal of phosphate residues 9H-(1,3-dichloro-9,9-dimethyl-7-hydroxyacridin-2-one) 9H-(9,9-dimethyl-7-hydroxyacridin-2-one) 9H-(1,3-dibromo-9,9-dimethyl-7-hydroxyacridin-2-one) Resorufin Umbelliferone (7-hydroxycoumarin) 4-Methylumbelliferone 4-Trifluoromethylumbelliferone 3-Cyanoumbelliferone 3-Phenylumbelliferone 3,4-Dimethylumbelliferone 3-Acetylumbelliferone 6-Methoxyumbelliferone SNAFL ™ Fluorescein-alkyl ether Naphthofluorescein Naphthofluorescein alkyl ether SNARF ™ Rhodol green ™ meso-Hydroxymonocarbocyanine meso-Hydroxytricarbocyanine meso-Hydroxydicarbocyanine bis-(1,3-dibutylbarbituric acid)pentamethine Oxonol 1-Ethyl-2-(naphthyl-1-vinylene)-3,3-dimethyl-4-(3H)-6-indolinium salt 2-Hydroxy-5′-chloro-phenyl-chloro-quinazolone Trifluoroacetyl-R110 Acetyl-R110 8-Hydroxy-2H-dibenz(b,f)azepin-2-one 8-hydroxy-11,11-dimethyl-11H-dibenz(b,e)(1,4)oxazepin-2-one Hydroxypyrene 2-hydroxy-11,11-dimethyl-11H-dibenz(b,e)(1,4)oxazepin-8-one
[0092] [0092] TABLE 2 Examples of detectable moieties that are detectable even when attached to the nucleoside polyphosphate Rhodamine green carboxylic acid Carboxy-fluorescein Pyrene Dansyl Bodipy Dimethylamino-coumarin carboxylic acid Eosin-5-isothiocyanate Methoxycoumarin carboxylic acid Texas Red Oregon Green ™ 488 carboxylic acid ROX TAMRA Anthracene-isothiocyanate Cy3 Cy3.5 Cy5 Cy5.5 Cy7 Cy7.5 Anilinonaphthalene-sulfonic acid
[0093] [0093] TABLE 3 Examples of Labeled Nucleoside Polyphosphates Adenosine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or A3P-DDAO Guanosine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or G3P-DDAO Cytidine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or C3P-DDAO Thymidine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or T3P-DDAO Uridine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or U3P-DDAO 2′-Deoxyadenosine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or dA3P-DDAO 2′-Deoxyguanosine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or dG3P-DDAO 2′-Deoxycytidine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or dC3P-DDAO 2′-Deoxythymidine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or dT3P-DDAO 2′-Deoxyuridine-5′-(γ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))triphosphate or dU3P-DDAO Adenosine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or A4P-DDAO Guanosine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or G4P-DDAO Cytidine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or C4P-DDAO Thymidine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or T4P-DDAO Uridine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or U4P-DDAO 2′-Deoxyadenosine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or dA4P-DDAO 2′-Deoxyguanosine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or dG4P-DDAO 2′-Deoxycytidine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or dC4P-DDAO 2′-Deoxythymidine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or dT4P-DDAO 2′-Deoxyuridine-5′-(δ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))tetraphosphate or dU4P-DDAO Adenosine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or A5P-DDAO Guanosine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or G5P-DDAO Cytidine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one))) pentaphosphate or C5P-DDAO Thymidine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or T5P-DDAO Uridine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or U5P-DDAO 2′-Deoxyadenosine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or dA5P-DDAO 2′-Deoxyguanosine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or dG5P-DDAO 2′-Deoxycytidine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or dC5P-DDAO 2′-Deoxythymidine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or dT5P-DDAO 2′-Deoxyuridine-5′-(ε-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))pentaphosphate or dU5P-DDAO Adenosine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or A6P-DDAO Guanosine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or G6P-DDAO Cytidine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or C6P-DDAO Thymidine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or T6P-DDAO Uridine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or U6P-DDAO 2′-Deoxyadenosine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or dA6P-DDAO 2′-Deoxyguanosine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or dG6P-DDAO 2′-Deoxycytidine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or dC6P-DDAO 2′-Deoxythymidine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or dT6P-DDAO 2′-Deoxyuridine-5′-(ζ-7-(9H-(1,3-dichloro-9,9-dimethylacridin-2-one)))hexaphosphate or dU6P-DDAO Adenosine-5′-(γ-7-umbelliferone)triphosphate or A3P-Umb Guanosine-5′-(γ-7-umbelliferone)triphosphate or G3P-Umb Cytidine-5′-(γ-7-umbelliferone)triphosphate or C3P-Umb Thymidine-5′-(γ-7-umbelliferone)triphosphate or T3P-Umb Uridine-5′-(γ-7-umbelliferone)triphosphate or U3P-Umb 2′-Deoxyadenosine-5′-(γ-7-umbelliferone)triphosphate or dA3P-Umb 2′-Deoxyguanosine-5′-(γ-7-umbelliferone)triphosphate or dG3P-Umb 2′-Deoxycytidine-5′-(γ-7-umbelliferone)triphosphate or dC3P-Umb 2′-Deoxythymidine-5′-(γ-7-umbelliferone)triphosphate or dT3P-Umb 2′-Deoxyuridine-5′-(γ-7-umbelliferone)triphosphate or dU3P-Umb Adenosine-5′-(δ-7-umbelliferone)tetraphosphate or A4P-Umb Guanosine-5′-(δ-7-umbelliferone)tetraphosphate or G4P-Umb Cytidine-5′-(δ-7-umbelliferone)tetraphosphate or C4P-Umb Thymidine-5′-(δ-7-umbelliferone)tetraphosphate or T4P-Umb Uridine-5′-(δ-7-umbelliferone)tetraphosphate or U4P-Umb 2′-Deoxyadenosine-5′-(δ-7-umbelliferone) tetraphosphate or dA4P-Umb 2′-Deoxyguanosine-5′-(δ-7-umbelliferone) tetraphosphate or dG4P-Umb 2′-Deoxycytidine-5′-(δ-7-umbelliferone) tetraphosphate or dC4P-Umb 2′-Deoxythymidine-5′-(δ-7-umbelliferone) tetraphosphate or dT4P-Umb 2′-Deoxyuridine-5′-(δ-7-umbelliferone) tetraphosphate or dU4P-Umb Adenosine-5′-(ε-7-umbelliferone) pentaphosphate or A5P-Umb Guanosine-5′-(ε-7-umbelliferone) pentaphosphate or G5P-Umb Cytidine-5′-(ε-7-umbelliferone) pentaphosphate or C5P-Umb Thymidine-5′-(ε-7-umbelliferone) pentaphosphate or T5P-Umb Uridine-5′-(ε-7-umbelliferone) pentaphosphate or U5P-Umb 2′-Deoxyadenosine-5′-(ε-7-umbelliferone) pentaphosphate or dA5P-Umb 2′-Deoxyguanosine-5′-(ε-7-umbelliferone) pentaphosphate or dG5P-Umb 2′-Deoxycytidine-5′-(ε-7-umbelliferone) pentaphosphate or dC5P-Umb 2′-Deoxythymidine-5′-(ε-7-umbelliferone) pentaphosphate or dT5P-Umb 2′-Deoxyuridine-5′-(ε-7-umbelliferone) pentaphosphate or dU5P-Umb Adenosine-5′-(ζ-7-umbelliferone)hexaphosphate or A6P-Umb Guanosine-5′-(ζ-7-umbelliferone)hexaphosphate or G6P-Umb Cytidine-5′-(ζ-7-umbelliferone)hexaphosphate or C6P-Umb Thymidine-5′-(ζ-7-umbelliferone)hexaphosphate or T6P-Umb Uridine-5′-(ζ-7-umbelliferone)hexaphosphate or U6P-Umb 2′-Deoxyadenosine-5′-(ζ-7-umbelliferone)hexaphosphate or dA6P-Umb 2′-Deoxyguanosine-5′-(ζ-7-umbelliferone)hexaphosphate or dG6P-Umb 2′-Deoxycytidine-5′-(ζ-7-umbelliferone)hexaphosphate or dC6P-Umb 2′-Deoxythymidine-5′-(ζ-7-umbelliferone)hexaphosphate or dT6P-Umb 2′-Deoxyuridine-5′-(ζ-7-umbelliferone)hexaphosphate or dU6P-Umb Adenosine-5′-(γ-7-(4-methylumbelliferone))triphosphate or A3P-MeUmb Guanosine-5′-(γ-7-(4-methylumbelliferone))))triphosphate or G3P-MeUmb Cytidine-5′-(γ-7-(4-methylumbelliferone))triphosphate or C3P-MeUmb Thymidine-5′-(γ-7-(4-methylumbelliferone))triphosphate or T3P-MeUmb Uridine-5′-(γ-7-(4-methylumbelliferone))triphosphate or U3P-MeUmb 2′-Deoxyadenosine-5′-(γ-7-(4-methylumbelliferone))triphosphate or dA3P-MeUmb 2′-Deoxyguanosine-5′-(γ-7-(4-methylumbelliferone))triphosphate or dG3P-MeUmb 2′-Deoxycytidine-5′-(γ-7-(4-methylumbelliferone))triphosphate or dC3P-MeUmb 2′-Deoxythymidine-5′-(γ-7-(4-methylumbelliferone))triphosphate or dT3P-MeUmb 2′-Deoxyuridine-5′-(γ-7-(4-methylumbelliferone))triphosphate or dU3P-MeUmb Adenosine-5′-(δ-7-(4-methylumbelliferone))tetraphosphate or A4P-MeUmb Guanosine-5′-(δ-7-(4-methylumbelliferone))))tetraphosphate or G4P-MeUmb Cytidine-5′-(δ-7-(4-methylumbelliferone))tetraphosphate or C4P-MeUmb Thymidine-5′-(δ-7-(4-methylumbelliferone))tetraphosphate or T4P-MeUmb Uridine-5′-(δ-7-(4-methylumbelliferone))tetraphosphate or U4P-MeUmb 2′-Deoxyadenosine-5′-(δ-7-(4-methylumbelliferone)) tetraphosphate or dA4P-MeUmb 2′-Deoxyguanosine-5′-(δ-7-(4-methylumbelliferone)) tetraphosphate or dG4P-MeUmb 2′-Deoxycytidine-5′-(δ-7-(4-methylumbelliferone)) tetraphosphate or dC4P-MeUmb 2′-Deoxythymidine-5′-(δ-7-(4-methylumbelliferone)) tetraphosphate or dT4P-MeUmb 2′-Deoxyuridine-5′-(δ-7-(4-methylumbelliferone))tetraphosphate or dU4P-MeUmb Adenosine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or A5P-MeUmb Guanosine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or G5P-MeUmb Cytidine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or C5P-MeUmb Thymidine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or T5P-MeUmb Uridine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or U5P-MeUmb 2′-Deoxyadenosine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or dA5P-MeUmb 2′-Deoxyguanosine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or dG5P-MeUmb 2′-Deoxycytidine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or dC5P-MeUmb 2′-Deoxythymidine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or dT5P-MeUmb 2′-Deoxyuridine-5′-(ε-7-(4-methylumbelliferone))pentaphosphate or dU5P-MeUmb Adenosine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or A6P-MeUmb Guanosine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or G6P-MeUmb Cytidine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or C6P-MeUmb Thymidine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or T6P-MeUmb Uridine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or U6P-MeUmb 2′-Deoxyadenosine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or dA6P-MeUmb 2′-Deoxyguanosine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or dG6P-MeUmb 2′-Deoxycytidine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or dC6P-MeUmb 2′-Deoxythymidine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or dT6P-MeUmb 2′-Deoxyuridine-5′-(ζ-7-(4-methylumbelliferone))hexaphosphate or dU6P-MeUmb Adenosine-5′-(γ-7-resorufin)triphosphate or A3P-RR Guanosine-5′-(γ-7-resorufin)))triphosphate or G3P-RR Cytidine-5′-(γ-7-resorufin)triphosphate or C3P-RR Thymidine-5′-(γ-7-resorufin)triphosphate or T3P-RR Uridine-5′-(γ-7-resorufin)triphosphate or U3P-RR 2′-Deoxyadenosine-5′-(γ-7-resorufin) triphosphate or dA3P-RR 2′-Deoxyguanosine-5′-(γ-7-resorufin) triphosphate or dG3P-RR 2′-Deoxycytidine-5′-(γ-7-resorufin) triphosphate or dC3P-RR 2′-Deoxythymidine-5′-(γ-7-resorufin) triphosphate or dT3P-RR 2′-Deoxyuridine-5′-(γ-7-resorufin) triphosphate or dU3P-RR Adenosine-5′-(δ-7-resorufin)tetraphosphate or A4P-RR Guanosine-5′-(δ-7-resorufin)))tetraphosphate or G4P-RR Cytidine-5′-(δ-7-resorufin)tetraphosphate or C4P-RR Thymidine-5′-(δ-7-resorufin)tetraphosphate or T4P-RR Uridine-5′-(δ-7-resorufin)tetraphosphate or U4P-RR 2′-Deoxyadenosine-5′-(δ-7-resorufin) tetraphosphate or dA4P-RR 2′-Deoxyguanosine-5′-(δ-7-resorufin) tetraphosphate or dG4P-RR 2′-Deoxycytidine-5′-(δ-7-resorufin) tetraphosphate or dC4P-RR 2′-Deoxythymidine-5′-(δ-7-resorufin) tetraphosphate or dT4P-RR 2′-Deoxyuridine-5′-(δ-7-resorufin) tetraphosphate or dU4P-RR Adenosine-5′-(ε-7-resorufin)pentaphosphate or A5P-RR Guanosine-5′-(ε-7-resorufin)pentaphosphate or G5P-RR Cytidine-5′-(ε-7-resorufin)pentaphosphate or C5P-RR Thymidine-5′-(ε-7-resorufin)pentaphosphate or T5P-RR Uridine-5′-(ε-7-resorufin)pentaphosphate or U5P-RR 2′-Deoxyadenosine-5′-(ε-7-resorufin)pentaphosphate or dA5P-RR 2′-Deoxyguanosine-5′-(ε-7-resorufin)pentaphosphate or dG5P-RR 2′-Deoxycytidine-5′-(ε-7-resorufin) pentaphosphate or dC5P-RR 2′-Deoxythymidine-5′-(ε-7-resorufin) pentaphosphate or dT5P-RR 2′-Deoxyuridine-5′-(ε-7-resorufin) pentaphosphate or dU5P-RR Adenosine-5′-(ζ-7-resorufin)hexaphosphate or A6P-RR Guanosine-5′-(ζ-7-resorufin)hexaphosphate or G6P-RR Cytidine-5′-(ζ-7-resorufin)hexaphosphate or C6P-RR Thymidine-5′-(ζ-7-resorufin)hexaphosphate or T6P-RR Uridine-5′-(ζ-7-resorufin)hexaphosphate or U6P-RR 2′-Deoxyadenosine-5′-(ζ-7-resorufin) hexaphosphate or dA6P-RR 2′-Deoxyguanosine-5′-(ζ-7-resorufin) hexaphosphate or dG6P-RR 2′-Deoxycytidine-5′-(ζ-7-resorufin)hexaphosphate or dC6P-RR 2′-Deoxythymidine-5′-(ζ-7-resorufin)hexaphosphate or dT6P-RR 2′-Deoxyuridine-5′-(ζ-7-resorufin)hexaphosphate or dU6P-RR Adenosine-5′-(γ-3′-(6′-ethoxyfluorescein))triphosphate or A3P-FlEt Guanosine-5′-(γ-3′-(6′-ethoxyfluorescein) triphosphate or G3P-FlEt Cytidine-5′-(γ-3′-(6′-ethoxyfluorescein))triphosphate or C3P-FlEt Thymidine-5′-(γ-3′-(6′-ethoxyfluorescein))triphosphate or T3P-FlEt Uridine-5′-(γ-3′-(6′-ethoxyfluorescein))triphosphate or U3P-FlEt 2′-Deoxyadenosine-5′-(γ-3′-(6′-ethoxyfluorescein)) triphosphate or dA3P-FlEt 2′-Deoxyguanosine-5′-(γ-3′-(6′-ethoxyfluorescein)) triphosphate or dG3P-FlEt 2′-Deoxycytidine-5′-(γ-3′-(6′-ethoxyfluorescein)) triphosphate or dC3P-FlEt 2′-Deoxythymidine-5′-(γ-3′-(6′-ethoxyfluorescein)) triphosphate or dT3P-FlEt 2′-Deoxyuridine-5′-(γ-3′-(6′-ethoxyfluorescein)) triphosphate or dU3P-FlEt Adenosine-5′-(δ-3′-(6′-ethoxyfluorescein))tetraphosphate or A4P-FlEt Guanosine-5′-(δ-3′-(6′-ethoxyfluorescein))tetraphosphate or G4P-FlEt Cytidine-5′-(δ-3′-(6′-ethoxyfluorescein))tetraphosphate or C4P-FlEt Thymidine-5′-(δ-3′-(6′-ethoxyfluorescein))tetraphosphate or T4P-FlEt Uridine-5′-(δ-3′-(6′-ethoxyfluorescein))tetraphosphate or U4P-FlEt 2′-Deoxyadenosine-5′-(δ-3′-(6′-ethoxyfluorescein)) tetraphosphate or dA4P-FlEt 2′-Deoxyguanosine-5′-(δ-3′-(6′-ethoxyfluorescein)) tetraphosphate or dG4P-FlEt 2′-Deoxycytidine-5′-(δ-3′-(6′-ethoxyfluorescein)) tetraphosphate or dC4P-FlEt 2′-Deoxythymidine-5′-(δ-3′-(6′-ethoxyfluorescein)) tetraphosphate or dT4P-FlEt 2′-Deoxyuridine-5′-(δ-3′-(6′-ethoxyfluorescein)) tetraphosphate or dU4P-FlEt Adenosine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or A5P-FlEt Guanosine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or G5P-FlEt Cytidine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or C5P-FlEt Thymidine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or T5P-FlEt Uridine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or U5P-FlEt 2′-Deoxyadenosine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or dA5P-FlEt 2′-Deoxyguanosine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or dG5P-FlEt 2′-Deoxycytidine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or dC5P-FlEt 2′-Deoxythymidine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or dT5P-FlEt 2′-Deoxyuridine-5′-(ε-3′-(6′-ethoxyfluorescein))pentaphosphate or dU5P-FlEt Adenosine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or A6P-FlEt Guanosine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or G6P-FlEt Cytidine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or C6P-FlEt Thymidine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or T6P-FlEt Uridine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or U6P-FlEt 2′-Deoxyadenosine-5′-(ζ-3′-(6′-ethoxyfluorescein)) hexaphosphate or dA6P-FlEt 2′-Deoxyguanosine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or dG6P-FlEt 2′-Deoxycytidine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or dC6P-FlEt 2′-Deoxythymidine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or dT6P-FlEt 2′-Deoxyuridine-5′-(ζ-3′-(6′-ethoxyfluorescein))hexaphosphate or dU6P-FlEt
[0094] Wherein the phosphorylated label in Formula I is a fluorogenic moiety, it is desirably selected from one of the following (all shown as the phosphomonester): 2-(5′-chloro-2′-phosphoryloxyphenyl)-6-chloro-4-(3H)-quinazolinone, sold under the trade name ELF 97 (Molecular Probes, Inc.), fluorescein diphosphate (tetraammonium salt), fluorescein 3′(6′)-O-alkyl-6′(3′)-phosphate, 9H-(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl)phosphate (diammonium salt), 4-methylumbelliferyl phosphate (free acid), resorufin phosphate, 4-trifluoromethylumbelliferyl phosphate, umbelliferyl phosphate, 3-cyanoubelliferyl phosphate, 9,9-dimethylacridin-2-one-7-yl phosphate, 6,8-difluoro-4-methylumbelliferyl phosphate and derivatives thereof.
[0095] Wherein the phosphorylated label moiety in Formula I above is a chromogenic moiety, it may be selected from the following: 5-bromo-4-chloro-3-indolyl phosphate, 3-indoxyl phosphate, p-nitrophenyl phosphate and derivatives thereof. The structures of these chromogenic dyes are shown as the phosphomonoesters below.
[0096] The moiety at the terminal-phosphate position may further be a chemiluminescent compound wherein it is desired that it is a phosphatase-activated 1,2-dioxetane compound. The 1,2-dioxetane compound may include, but is not limited to, disodium 2-chloro-5-(4-methoxyspiro[1,2-dioxetane-3,2′-(5-chloro-)tricyclo[3,3,1-[3,7]-decan]-1-yl)-1-phenyl phosphate, sold under the trade name CDP-Star (Tropix, Inc., Bedford, Mass.), chloroadamant-2′-ylidenemethoxyphenoxy phosphorylated dioxetane, sold under the trade name CSPD (Tropix), and 3-(2′-spiroadamantane)-4-methoxy-4-(3″-phosphoryloxy)phenyl-1,2-dioxetane, sold under the trade name AMPPD (Tropix). The structures of these commercially available dioxetane compounds are disclosed in U.S. Pat. Nos. 5,582,980, 5,112,960 and 4,978,614, respectively, and are incorporated herein by reference.
[0097] The methods described above may further include the step of quantifying the nucleic acid sequence. In a related aspect, the detectable species may be produced in amounts substantially proportional to the amount of an amplified nucleic acid sequence. The step of quantifying the nucleic acid sequence is desired to be done by comparison of spectra produced by the detectable species with known spectra.
[0098] The present invention further provides a method of amplifying a nucleic acid sequence in the presence of a terminal-phosphate labeled nucleoside polyphosphate stabilizer such as polyol (glycerol, threitol, etc.), a polyether including cyclic polyethers, polyethylene glycol, organic or inorganic salts, such as ammonium sulfate, sodium sulfate, sodium molybdate, sodium tungstate, organic sulfonate, etc., in conjunction with a terminal-phosphate labeled nucleoside polyphosphate in the presence of a metal salt, such as manganese, magnesium, zinc, calcium or cobalt salts, to decrease the background signal generation in an enzymatic assay. Additives such as weak chelators have been used in the prior art during nucleic acid polymerization reactions in the presence of manganese. Their purpose, however was to reduce the rate of misincorporation of nucleotides caused by manganese. As shown in FIG. 6, even in the absence of additives, there is no misincorporation of the terminal-phosphate labeled nucleotides by polymerases. Hence, the purpose of adding additives in the current invention is solely to reduce non-enzymatic hydrolysis of terminal-phosphate labeled nucleotides caused by metal salts, to reduce background.
[0099] In one embodiment, the invention provides a method of quantifying a nucleic acid including the steps of: (a) conducting a nucleic acid amplification reaction, the amplification reaction including the reaction of at least one terminal-phosphate-labeled nucleotide, wherein the reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable by-product species in an amount substantially proportional to the amount of the nucleic acid to be quantified; (c) measuring the detectable species; and (d) comparing the measurements using known standards to determine the quantity of the nucleic acid. In this embodiment of the method of quantifying a nucleic acid, the nucleic acid to be quantified may be RNA. The nucleic acid may further be a natural or synthetic oligonucleotide, chromosomal DNA, or DNA.
[0100] In another embodiment, the invention provides a method of quantifying a nucleic acid including the steps of: (a) conducting a nucleic acid amplification reaction in the presence of a manganese salt, the amplification reaction including the reaction of at least one terminal-phosphate-labeled nucleotide, wherein the reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable by-product species in an amount substantially proportional to the amount of the nucleic acid to be quantified; (c) measuring the detectable species; and (d) comparing the measurements using known standards to determine the quantity of the nucleic acid.
[0101] The invention further provides a method of quantifying a DNA sequence including the steps of: (a) conducting a DNA amplification reaction in the presence of a terminal-phosphate-labeled nucleotide wherein the reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable by-product species in amounts substantially proportional to the amount of the DNA sequence to be quantified; (c) measuring the detectable species; and (d) comparing measurements using known standards to determine the quantity of DNA. In this embodiment, the DNA sequence for quantification may include natural or synthetic oligonucleotides, or DNA isolated from cells including chromosomal DNA.
[0102] The invention further provides a method of quantifying a DNA sequence including the steps of: (a) conducting a DNA amplification reaction in the presence of a manganese salt and a terminal-phosphate-labeled nucleotide wherein the reaction results in the production of labeled polyphosphate; (b) permitting the labeled polyphosphate to react with a phosphatase to produce a detectable by-product species in amounts substantially proportional to the amount of the DNA sequence to be quantified; (c) measuring the detectable species; and (d) comparing measurements using known standards to determine the quantity of DNA.
[0103] In each of these methods of quantifying a nucleic acid sequence described above, the polymerase reaction step may further include conducting the polymerase reaction in the presence of a phosphatase. As described earlier in the specification, this would permit real-time monitoring of nucleic acid polymerase activity and hence, real-time detection of a target nucleic acid sequence for quantification.
[0104] The terminal-phosphate-labeled nucleotide useful for the methods of quantifying the nucleic acid sequence provided herein may be represented by Formula I shown above. The enzyme-activatable label becomes detectable through the enzymatic activity of phosphatase which changes the phosphate ester linkage between the label and the terminal-phosphate of a natural or modified nucleotide in such a way to produce a detectable species. The detectable species is detectable by the presence of any one of or a combination of color, fluorescence emission, chemiluminescence, mass difference or electrochemical potential. As already described above, the enzyme-activatable label may be a 1,2-dioxetane chemiluminescent compound, fluorescent dye, chromogenic dye, a mass tag or an electrochemical tag or a combination thereof. Suitable labels are the same as those described above.
[0105] Another aspect of the invention relates to a nucleic acid detection kit including:
[0106] (a) at least one or more terminal-phosphate-labeled nucleotide according to Formula I:
[0107] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is a label containing a hydroxyl group, a sulfhydryl group, a haloalkyl group or an amino group suitable for forming a phosphate ester, a thioester, alkylphosphonate or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label and may contain a linker between P and L; and
[0108] (b) at least one nucleic acid polymerase.
[0109] Another aspect of the invention relates to a nucleic acid detection kit including:
[0110] (a) at least one or more terminal-phosphate-labeled nucleotide according to Formula I:
[0111] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is a label containing a hydroxyl group, a sulfhydryl group, a haloalkyl group or an amino group suitable for forming a phosphate ester, a thioester, alkylphosphonate or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label and may contain a linker between P and L;
[0112] (b) at least one nucleic acid polymerase; and
[0113] (c) a reaction buffer containing a manganese salt.
[0114] Another aspect of the invention relates to a nucleic acid detection kit including:
[0115] (a) at least one or more terminal-phosphate-labeled nucleotide according to Formula I:
[0116] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is a label containing a hydroxyl group, a sulfhydryl group, a haloalkyl group or an amino group suitable for forming a phosphate ester, a thioester, alkylphosphonate or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label and may contain a linker between P and L;
[0117] (b) at least one nucleic acid polymerase;
[0118] (c) a reaction buffer containing a manganese salt; and
[0119] (d) a stabilizer
[0120] Another aspect of the invention relates to a nucleic acid detection kit including:
[0121] (a) at least one or more terminal-phosphate-labeled nucleotide according to Formula I:
[0122] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is an enzyme-activatable label containing a hydroxyl group, a sulfhydryl group or an amino group suitable for forming a phosphate ester, a thioester or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label and may contain a linker between P and L; and
[0123] (b) at least one nucleic acid polymerase.
[0124] (c) a phosphatase
[0125] Another aspect of the invention relates to a nucleic acid detection kit including:
[0126] (a) at least one or more terminal-phosphate-labeled nucleotide according to Formula I below:
[0127] wherein P is phosphate (PO 3 ) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is an enzyme-activatable label containing a hydroxyl group, a sulfhydryl group or an amino group suitable for forming a phosphate ester, a thioester or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label which preferably becomes independently detectable when the phosphate is removed;
[0128] (b) at least one thermostable nucleic acid polymerase;
[0129] (c) a phosphatase; and
[0130] (d) reaction buffer containing a Manganese salt.
[0131] Another aspect of the invention relates to a nucleic acid detection kit including:
[0132] (a) at least one or more terminal-phosphate-labeled nucleotide according to Formula I:
[0133] wherein P is phosphate (PO 3 ) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is an enzyme-activatable label containing a hydroxyl group, a sulfhydryl group or an amino group suitable for forming a phosphate ester, a thioester or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label which preferably becomes independently detectable when the phosphate is removed;
[0134] (b) at least one thermostable nucleic acid polymerase;
[0135] (c) a phosphatase;
[0136] (d) reaction buffer containing a Manganese salt; and
[0137] (e) a stabilizer.
[0138] Another aspect of the invention relates to a nucleic acid quantification kit including:
[0139] (a) at least one or more terminal-phosphate-labeled nucleotide according to Formula I:
[0140] wherein P is phosphate (PO3) and derivatives thereof, n is 2 or greater; Y is an oxygen or sulfur atom; B is a nitrogen-containing heterocyclic base; S is a sugar moiety; L is an enzyme-activatable label containing a hydroxyl group, a sulfhydryl group or an amino group suitable for forming a phosphate ester, a thioester or a phosphoramidate linkage at the terminal phosphate of a natural or modified nucleotide; P-L is a phosphorylated label which preferably becomes independently detectable when the phosphate is removed;
[0141] (b) at least one thermostable nucleic acid polymerase; and
[0142] (c) phosphatase.
[0143] The sugar moiety in the terminal-phosphate-labeled nucleotide included in the kit may include, but is not limited to ribosyl, 2′-deoxyribosyl, 2′-alkoxyribosyl, 2′-aminoribosyl, 2′-fluororibosyl and other modified sugars.
[0144] The base may be, but is not limited to uracil, thymine, cytosine, 5-methylcytosine, guanine, 7-deazaguanine, hypoxanthine, 7-deazahypoxanthine, adenine, 7-deazaadenine and 2,6-diaminopurine and analogs thereof.
[0145] Furthermore, as described above, the enzyme-activatable label may be a 1,2-dioxetane chemiluminescent compound, fluorescent dye, chromogenic dye, a mass tag, an electrochemical tag or a combination thereof. Suitable compounds for conjugation at the terminal-phosphate position of the nucleotide are the same as those described above.
EXAMPLES
[0146] The following examples illustrate certain preferred embodiments of the illustration but are not intended to be illustrative of all embodiments.
Example 1
[0147] Preparation of δ-9H(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl)-deoxythymidine-5′-tetraphosphate (dT4P-DDAO) and related compounds
[0148] 10 μmoles TTP TEA salt was evaporated to dryness. To the residue was added 40 μmoles tributylamine and 5 ml dry pyridine. The solution was re-evaporated to dryness. After 2 coevaporations with 3 ml dry dimethylformamide (DMF), residue was re-dissolved in 200 μl dry DMF, flushed with argon and stoppered. Using a syringe, 50 μmoles (8 mg) carbonyldiimidazole (CDI) dissolved in 100 μl dry DMF was added. The flask was stirred for 4 hr at ambient temperature.
[0149] While the above reaction was progressing, 35 mg (83 μmoles) DDAO phosphate and 166 μmoles tributylamine were dissolved in dry DMF. The DDAO phosphate was evaporated to dryness followed by 3 coevaporations with dry DMF. Residue was dissolved in 300 μl dry DMF.
[0150] After the 4 hr reaction time, 3.2 μl anhydrous methanol was added to the TTP-CDI reaction. The reaction was stirred 30 minutes. To this mixture, DDAO phosphate solution was added and mixture was stirred at ambient temperature for 18 hr. The reaction was checked by Reverse phase HPLC (Xterra 4.6×100 column, 0.1M TEAA/acetonitrile). The reaction volume was reduced to 200% by evaporation and the reaction was allowed to progress for 80 hr.
[0151] After 80 hr, the reaction was stopped by adding 15 ml 0.1 M TEAB. The diluted mixture was applied to a 1 9×100 Xterra RP column and eluted with an acetonitrile gradient in 0.1 M TEAB. The fractions containing pure DDAO T4P were evaporated to dryness and coevaporated twice with ethanol. The residue was reconstituted with MilliQ water. Yield: 1.10 μmole, 11%; HPLC purity >98% at 455 nm; MS: M-1=850.07 (calc. 849.95)
[0152] δ-9H(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl)-deoxyguanosine-5′-tetraphosphate (dG4P-DDAO), δ-9H(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl)-deoxycytidine-5′-tetraphosphate (dC4P-DDAO) and δ-9H(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl)-deoxyadenosine-5′-tetraphosphate (dA4P-DDAO) were prepared in a similar manner as described above except 3.5 equivalents of DDAO phosphate was used instead of 8.3 equivalents. After C18 purification, samples were purified on ion exchange using a Mono Q 10/10 column.
[0153] δ-9H(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl)-deoxyguanosine-5′-tetraphosphate (dG4P-DDAO): Yield 0.57 μmole, 5.7%; HPLC purity 99% at 455 nm; MS: M-1=875.03 (calc. 874.96).
[0154] δ-9H(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl)-deoxycytidine-5′-tetraphosphate (dC4P-DDAO): Yield 0.24 μmole, 2.4%; HPLC purity 99% at 455 nm; MS: M-1=835.03 (calc. 834.95).
[0155] δ-9H(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl)-deoxyadenosine-5′-tetraphosphate (dA4P-DDAO): Yield 0.38 μmole, 3.8%; HPLC purity 99% at 455 nm; MS: M-1=859.07 (calc. 858.97).
[0156] PCR Amplification of a Target Sequence Using Terminal-Phosphate Labeled nucleotide Polyphosphate
[0157] Polymerase chain reaction (PCR) mixtures (20 μl) contained 20 mM Tris-HCL (pH 8.75), 10 mM KCL, 10 mM (NH 4 ) 2 SO 4 , 2 mM MgSO 4 , 1 mg/ml bovine serum albumin and 0.1% (v/v) Triton X-100. The final nucleotide concentrations were 20 μM each, and 2.5 units of the DNA polymerase were used for each reaction. The initial template DNA (1-5 ng) was either pUC18 or pUCp53 (Amersham Biosciences). The sequences of the primers, along with the sequence of the amplified segment of pUCp53 are shown in Table 4. The initial amount of primer was 2 μmol each, and 2.5 units of the indicated DNA polymerase was used. Reactions were carried out for 15 thermal cycles of 90° C., 30 sec.; 55° C., 60 sec.; and 72° C., 300 sec. Most PCR reactions also included MnCl 2 at a final concentration of 0.08-0.2 mM. Reaction products were loaded onto 1.6% agarose gels. The gels were stained with SYBR Gold (Molecular Probes) according to the manufacturers' instructions and scanned at 532 nm using a Typhoon fluorescence scanner (Amersham Biosciences). Gel size markers were a 100 bp ladder (Amersham Biosciences).
[0158] The DNA polymerases used for these experiments included Taq DNA polymerase, Thermo Sequenase DNA polymerase (Amersham Biosciences), Tba exo-DNA polymerase (from Thermococcus barosii, U.S. Pat. No. 5,602,011 with D141A and E143A amino acid substitutions U.S. Pat. No. 5,882,904), Pfu DNA polymerase (Strategene), KOD XL DNA polymerase (Novagen) and Deep Vent DNA polymerase (New England BioLabs).
TABLE 4 DNA Sequences PCR Product from pUCp53 (SEQ ID NO: 1) CTGTGCAGCT GTGGGTTGAT TCCACACCCC CGCCCGGCAC 60 CCGCGTCCGC GCCATGGCCA TCTACAAGCA GTCACAGCAC ATGACGGAGG TTGTGAGGCG CT 102 P53SNP22C-51F (SEQ ID NO: 2) CTGTGCAGCT GTGGGTTGAT TC P53SNP22G131R (SEQ ID NO: 3) AGCGCCTCAC AACCTCCGTC AT -21 Forward Primer (SEQ ID NO: 4) TGTAAAACGA CGGCCAGT -28 Reverse Primer (SEQ ID NO: 5) AGGAAACAGC TATGACCAT
[0159] [0159]FIG. 1 shows the results of PCR using several DNA polymerases and either normal nucleotides (lanes 10-12) or a mixture of dATP, dGTP, dCTP and □-DDAO dT tetra Phosphate (DDAO-dT4P). For this experiment, either Taq DNA polymerase (lanes 1-3, 12), Thermo Sequenase (Amersham Biosciences) DNA polymerase (lanes 7-9, 11) or Tba exo-DNA polymerase (lanes 4-6, 10) were used. The MnCl 2 concentration was 0 mM for the reactions resolved in lanes 1, 4, 7 and 10-12; 0.2 mM in lanes 2, 5, and 8; 0.4 mM in lanes 3, 6 and 9. For all samples, the template DNA was pUCp53 and the primers were P53SNP22C-51F and P53SNP22G131R. As shown in the figure, significant amounts of PCR product were made by all three polymerases using normal nucleotides, but only by the Tba exo-polymerase when DDAO-dT4P replaced dTTP, and that PCR yield is increased at least 5-fold in the presence of 0.2-0.4 mM MnCl 2 . In similar experiments (not shown), it was found that product yield is increased with as little as 0.04 mM MnCl 2 , and as much as 1.0 mM MnCl 2 . It is interesting to note that MnCl 2 is not required when normal dNTPs are used, and in fact MnCl 2 reduces the yield of these PCR amplifications (data not shown). In addition, PCR product is made by Pfu DNA polymerase and by KOD XL DNA polymerase under the same conditions. It is also interesting to note that the failure of some polymerases to make amplification products suggests that the successful amplification by Tba exo-DNA polymerase and other polymerases was not achieved by simple breakdown of the phosphate-modified nucleotide.
Example 3
[0160] Detection of PCR products by fluorescence.
[0161] Shrimp alkaline phosphatase (Amersham Biosciences), 0.1 unit, was added to the products of the reactions displayed in lanes 2 and 5 of FIG. 1 and incubated at 37° C. for 30 minutes. Then the fluorescence was determined using a FarCYte fluorescence plate reader (Amersham Biosciences) using 650 nm excitation and 670 nm emission. The reaction product of Taq polymerase (producing little or no detectable PCR product) gave a reading of 5500 fluorescence units. The reaction product of Tba exo-DNA polymerase gave a reading of 31,000 fluorescence units. This indicates that simple fluorescence readings detecting the free DDAO fluorescence can be used to detect successful PCR amplification.
Example 4
[0162] PCR with additional nucleotides, templates and primers.
[0163] [0163]FIG. 2 shows the products of amplification of the same template as for FIG. 1 with the same primers. FIG. 3 shows the products of amplification of pUC 18 DNA using −21 Forward and −28 Reverse primers (Table 1). For both figures, the amplification reaction loaded in lane 1 was performed with normal dNTPs and without MnCl 2 . For the lanes marked 2, the dTTP was replaced by dT4P-DDAO and the reactions contained 0.2 mM MnCl 2 . For the lanes marked 3, the dGTP was replaced by dG4P-DDAO, and for the lanes marked 4, the dGTP was replaced by dG4P-MeCoumarin again with 0.2 mM MnCl 2 . All amplifications successfully produced product of the expected size, suggesting that amplification is independent of the base or dye moiety in the modified nucleotides.
Example 5
[0164] Effect of additives on non-enzymatic hydrolysis of terminal-phosphate labeled nucleoside polyphosphates
[0165] Seventy μl samples containing 50 mM Hepes, pH 8.0, 5 mM MgCl2, 0.5 mM MnCl 2 , 0.01% Tween-20, 1 μm ddT4P-EtFl, 100 nM primer/template, 0.0036 units/μl SAP with or without 5% glycerol were cycled as follows: 95° C., 30 sec and 50° C., 3 min, repeat 10 times. Amount of free dye formed was checked in a fluorimeter. In the absence of glycerol concentration of free dye formed was 151 nM compared to only 19 nM in the presence of glycerol (close to the value observed in the absence of manganese, 8 nM). Clearly at high temperatures glycerol reduces the amount of degradation caused by manganese.
Example 6
[0166] Effect of Ammonium Sulfate as an additive on non-enzymatic hydrolysis of terminal-phosphate labeled nucleoside polyphosphates in the presence of MnCl 2 .
[0167] Twenty μl of 25 mM Tris.HCl, pH 9.0 containing 0.5 mM MnCl 2 , 1 μm dT4P-DDAO and 10 mM salt (see FIG. 4) were heated at 95° C. for 60 minutes. Four μl of each reaction mix was mixed with 16 μl of BAP solution in Hepes (0.005 units BAP/μl) and incubated at 37° C. for 60 minutes. Samples were read on Tecan ultra plate reader. Un heated sample and unheated sample without MnCl 2 were used as controls. Raw fluorescence counts were converted into % degradation by using fluorescence counts from a Snake Venom phosphodiesterase hydrolyzed sample as 100% degraded sample. FIG. 4 clearly shows that addition of ammonium sulfate clearly stabilizes the dT4P-DDAO. Some stabilization effect is also observed in the presence of sulfate ions (MgSO 4 ) and ammonium ions (NH 4 Cl).
Example 7
[0168] Effect of other salts as additives on non-enzymatic hydrolysis of terminal-phosphate labeled nucleoside polyphosphates in the presence of MnCl 2 .
[0169] Twenty μl of 25 mM Hepes, pH 8.1, containing 0.5 mM MnCl 2 , 1 lm dT4P-DDAO and 10 or 25 mM inorganic or organic salt (see FIG. 5) was heated at 95° C. for 60 minutes. 4 μl of each sample was treated with BAP as described above and read on Tecan ultra plate reader. An unheated sample with MnCl 2 (water lane) and a heated sample without Hepes and MnCl 2 were used as controls. Fluorescence counts were converted into % degradation as described above. Data in FIG. 5 clearly shows that ammonium sulfate, phosphonoacetate, sodium molybdate, sodium tungstate and sodium vanadate stabilize the nucleotide. Stabilization due to propane sulfonate on the other hand was minimal.
Example 8
[0170] PCR amplification using terminal phosphate labeled nucleoside polyphosphates in the presence of nucleotide stabilizing additives.
[0171] Polymerase chain reaction (PCR) mixtures (20 μl) contained 25 mM Hepes (pH 8.1), 10 mM KCl, 2 mM MgSO 4 , 0.25 mM MnCl 2 , 1 mg/ml bovine serum albumin, 0.01% (v/v) Tween-20 and 10-25 mM salt as shown in FIG. 6. Each sample also contained 20 μm each of dA4P-Me, dT4P-Me, dC4P-Me, 200 μm dG4P-FlEt, 0.006 units/l BAP, 2 units of T. ba polymerase, 0.1 μm −40 M13 forward primer, 0.1 μm −28 M13 reverse primer and 0.2 ng M13 DNA. In addition to the terminal-phosphate labeled nucleotide, terminal methyl-blocked dNTP's were used instead of normal dNTP's to prevent degradation by BAP (phosphatase). Latter is required for signal generation from dye-polyphosphate after the nucleotide is incorporated into DNA by polymerase. Reactions were carried out for 35 thermal cycles of 90° C., 30 sec.; 55° C., 30 sec.; and 65° C., 300 sec. Reaction products were loaded onto 1.6% agarose gels. The gels were stained with SYBR Gold (Molecular Probes) according to the manufacturers' instructions and scanned at 532 nm using a Typhoon fluorescence scanner (Amersham Biosciences). Gel size markers were a 100 bp ladder (Amersham Biosciences).
[0172] As shown in FIG. 6, PCR product was separated in the presence of ammonium sulfate, sodium molybdate and sodium tungstate as well as in the absence of any stabilizer. No product formed in the presence of sodium meta vanadate or phosphonoacetate. Considering that ammonium sulfate, sodium molybdate and tungstate not only stabilize terminal-phosphate labeled nucleoside polyphosphates but also allow DNA amplification, these salts are quite useful for use in quantitative amplification methods.
Example 9
[0173] Quantitative PCR using terminal-phosphate labeled nucleoside polyphosphates.
[0174] Polymerase chain reaction (PCR) mixtures (20 μl) contained 25 mM Tris.HCl (pH 9.0), 10 mM KCl, 2 mM MgSO 4 , 0.25 mM MnCl 2 , 1 mg/ml bovine serum albumin and 0.01% (v/v) Tween-20. Each sample also contained 20 μm each of dA4P-Me, dT4P-Me, dC4P-Me, 200 μm dG4P-FlEt, 0.005 units/μl BAP, 2 units of pfu (with A486Y mutation) polymerase, 0.1 μm −40 M13 forward primer, 0.1 μM −28 M13 reverse primer and 1.2×10 6 -1.2×109 copies of M13 DNA. In addition to the terminal-phosphate labeled nucleotide, the remaining nucleotides were blocked with a methyl group on the terminal phosphate to prevent degradation by BAP. Reactions were carried out for 50 thermal cycles of 90° C., 30 sec.; 55° C., 30 sec.; and 65° C., 300 sec on ABI 7900 instrument. Cycle count at which the fluorescence count reaches a certain threshold (corresponding to a fixed amount of amplification product) for each reaction was plotted against the amount of input M13 DNA copies to give a straight line (FIG. 7) indicating that the method can be used for the quantification of target DNA copy number in a given sample.
[0175] Reaction products were also loaded onto 1.6% agarose gels. The gels were stained with SYBR Gold (Molecular Probes) according to the manufacturers' instructions and scanned at 532 nm using a Typhoon fluorescence scanner (Amersham Biosciences) to show the formation of PCR product (FIG. 8). Gel size markers were a 100 bp ladder (Amersham Biosciences).
Example 10
[0176] DNA amplification by Rolling Circle Amplification (RCA) using terminal-phosphate labeled/blocked nucleoside polyphosphates
[0177] Varying amounts of denatured salmon sperm chromosomal DNA was taken in 25 mM Tris: borate buffer, pH 8.0, containing 5 mM ammonium sulfate, 75 mM NaCl, 5 mM MgCl2, 1 mM MnSO4, 0.01% Tween-20, 400 ng Phi29 DNA polymerase, 40 μm nuclease resistant random hexamers, 0.03 units of BAP and 50 μm each of dA4P-Me, dG4P-Me, dC4P-Me and dT4P-DDAO. Reactions were incubated at 30° C. in a Tecan fluorescent plate reader and were read every five minutes at excitation and emission wavelengths optimized for DDAO. Raw fluorescence counts are plotted as a function of time.
[0178] [0178]FIG. 9 clearly shows that in the absence of input DNA, no signal is produced. As the amount of DNA increases, the amount of fluorescence and hence the amount of product produced, increases. Furthermore, when the slope from the linear phase of amplification for each reaction (between 20-40 minutes) is plotted as a function of DNA input (FIG. 10), a linear correlation, between the amount of input DNA and the rate of product formation, is observed, indicating that this method can be used for quantifying DNA.
[0179] Having described the particular, desired embodiments of the invention herein, it should be appreciated that modifications may be made therethrough without departing from the contemplated scope of the invention. The true scope of the invention is set forth in the claims appended hereto.
1
5
1
102
DNA
artificial sequence
PCR product
1
ctgtgcagct gtgggttgat tccacacccc cgcccggcac ccgcgtccgc 50
gccatggcca tctacaagca gtcacagcac atgacggagg ttgtgaggcg 100
ct 102
2
22
DNA
artificial sequence
synthetic oligonucleotide
2
ctgtgcagct gtgggttgat tc 22
3
22
DNA
artificial sequence
synthetic oligonucleotide
3
agcgcctcac aacctccgtc at 22
4
18
DNA
artificial sequence
synthetic oligonucleotide
4
tgtaaaacga cggccagt 18
5
19
DNA
artificial sequence
synthetic oligonucleotide
5
aggaaacagc tatgaccat 19
|
The present invention relates generally to the use of terminal-phosphate-labeled nucleotides having three or more phosphates as substrates for nucleic acid polymerases and their use in DNA amplification. The labels employed are chemiluminescent, fluorescent, electrochemical and chromogenic moieties as well as mass tags and include those that are directly detectable, detectable after enzyme activation or feed into other processes to generate a different signal. The signal generated from the attached dyes may also be used to quantify the amount of amplification. Further provided are stabilizers that enhance the stability of terminal-phosphate labeled nucleoside polyphosphates in aqueous solutions and are useful for reducing non-enzymatic hydrolysis of these nucleotides, hence decrease background.
| 2
|
INCORPORATION BY REFERENCE
[0001] This application is based upon and claims the benefit of priority from Japanese patent application No. 2015-244669, filed on Dec. 15, 2015, the disclosure of which are incorporated herein in its entirety by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a measuring device. More specifically, the present invention relates to a measuring device having a pointer-type display part such as a lever-type dial gauge and a dial gauge.
[0004] 2. Description of Related Art
[0005] There is known a lever-type dial gauge (JP 3675587 B and JP 4399186 B). The lever-type dial gauge is used to inspect whether there is a machining error or whether the error is within a tolerance by performing comparative measurement mainly between a master or a block gauge and an object to be measured. The comparative measurement by the lever-type dial gauge has an extremely important role in inspection of dimensional accuracy of products.
SUMMARY OF THE INVENTION
[0006] If the exactly same lever-type dial gauge is used, the inspection result is frequently different from measurer to measure. As a result of the earnest investigation of the cause, the inventors of the present invention noticed that measurers' unintentional posture change is one of the reasons.
[0007] To perform comparative measurement, measurers should not change the posture when reading a scale. If the measurer changes the posture when measuring a master from that when measuring an object to be measured, the visual line to read the scale is changed, and the difference in the visual line directly causes a measurement error.
[0008] The reason why the measurer unintentionally changes the posture is that the pointer and the scale (graduation line) can be difficult to see sometimes.
[0009] FIG. 1 is a diagram illustrating a using state of a lever-type dial gauge 80 . Typically, the lever-type dial gauge 80 is mainly used with a display part 82 facing upward. Then, light of the illumination on the ceiling reflects on a cover plate 83 .
[0010] If the cover plate 83 has a slightly curved convex surface, the reflection is dispersed into a plurality of weak reflection spots 91 . However, light in various directions is reflected on the cover plate 83 .
[0011] If the cover plate 83 has a flat surface, light in only one direction is reflected, but a large strong reflection spot 91 appears.
[0012] Although a measurer determines the posture so as to easily see the pointer position (reference point) when a master or a gauge is measured, if the pointer position when a workpiece (object to be measured) is measured is covered with the reflection spot 91 , the measurer changes the posture to read the scale (graduation line) indicated by a pointer 84 .
[0013] In another case, when the difference in height between the left and the right of an object to be measured is measured, a dial gauge is moved to a measurement point to perform the measurement. For example, a dial gauge is attached to a jig or the like, and the reference point is adjusted at the measurement point of the left end of the object to be measured. Then, the dial gauge is moved together with the jig, and the difference from the reference point is read at the measurement point of the right end. In this measurement, although illumination is not reflected at the time when the reference point is adjusted, the illumination can be reflected at the position to which the dial gauge is moved. In this case, the measurer unintentionally changes the posture at the position to read the scale, which leads to a measurement error.
[0014] It is supposed to start the measurement of the master or the gauge again, but the remeasuement is troublesome. Furthermore, not all users correctly recognize the importance of not changing the posture, that is, fixing the angle of the visual line.
[0015] Thus, a purpose of the present invention is to provide a measuring device which reduces reading errors caused by parallax.
[0016] A measuring device according to an embodiment of the present invention has a gauge head to be contacted to an object to be measured, and includes:
[0017] a pointer-type display part configured to display displacement of the gauge head obtained by being enlarged by an enlarging mechanism and converted into a rotation amount of a pointer; and
[0018] a transparent cover plate provided so as to cover the pointer-type display part, in which the cover plate has an antireflection film on a surface.
[0019] In an embodiment of the present invention, it is preferable that the cover plate further has an antifouling film on the antireflection film.
[0020] In an embodiment of the present invention, it is preferable that the cover plate has a flat surface.
[0021] In an embodiment of the present invention, it is preferable that the pointer-type display part has a graduated dial plate, and the dial plate is rotatable about an axis of the pointer.
[0022] In an embodiment of the present invention, it is preferable that the measuring device is a lever-type dial gauge or a dial gauge.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a diagram illustrating a using state of a lever-type dial gauge;
[0024] FIG. 2 is a front view of a dial gauge (measuring device);
[0025] FIG. 3 is an exploded view of the dial gauge (measuring device);
[0026] FIG. 4 is a diagram illustrating an experimental example in the case that a cover plate having a convexly curved surface with no antireflection film is used;
[0027] FIG. 5 is a diagram illustrating an experimental example in the case that a cover plate having a flat surface with no antireflection film is used; and
[0028] FIG. 6 is a diagram illustrating an experimental example using an embodiment of the present embodiment.
DETAILED DESCRIPTION
[0029] An embodiment of the present invention is illustrated and described with reference to the reference signs attached to the elements in the drawings.
First Exemplary Embodiment
[0030] In the present embodiment, a dial gauge 10 is exemplified, but the present invention is effective in a lever-type dial gauge 80 , a pointer display type caliper, or micrometer. In other words, the present invention is effective in any of pointer display type small measuring devices.
[0031] FIG. 2 is a front view of the dial gauge 10 (measuring device).
[0032] FIG. 3 is an exploded view of the dial gauge 10 (measuring device).
[0033] The dial gauge 10 is to display displacement of a spindle 50 as a rotation amount of a pointer 71 .
[0034] The dial gauge 10 includes a main body case 40 , a spindle 50 , an enlarging mechanism 30 , and a main body cover 20 .
[0035] The main body case 40 is a short cylindrical case body one end face of which is opening. A stem 60 is provided in a protruding manner on the side face of the main body case 40 , and the stem 60 is a bearing of the spindle 50 .
[0036] The spindle 50 has a gauge head 51 at the tip, and the based end side is housed in the main body case 40 . The spindle 50 is supported by the stem 60 so as to be movable backward and forward in the axis direction.
[0037] The enlarging mechanism 30 enlarges and converts linear displacement of the spindle 50 into a rotation amount of a pointer 71 . The enlarging mechanism 30 is formed by combining a plurality of gears and housed inside the main body case 40 . The enlarging mechanism 30 has a pinion (not illustrated) which engages with a rack (not illustrated) provided to the spindle 50 , and enlarges the rotation of the pinion with a plurality of gear trains.
[0038] The main body cover 20 has an external frame part 21 and a cover plate 22 .
[0039] The external frame part 21 is a short cylinder both ends of which are opening, and attached to the opening side end face of the main body case 40 by sandwiching, for example, an O ring 41 in-between.
[0040] Here, when the external frame part 21 is attached to the end face of the main body case 40 , by sandwiching a dial plate 42 between the end face of the main body case 40 and the external frame part 21 , the dial plate 42 is fixed to the end face of the main body case 40 .
[0041] Furthermore, the pointer 71 is arranged on the dial plate 42 , and a pointer axis 72 is coupled to a center pinion (not illustrated) which is the final stage of the enlarging mechanism 30 .
[0042] Here, the pointer 71 and the dial plate 42 constitute a pointer-type display part.
[0043] The external frame part 21 is rotatable with respect to the main body case 40 , and when the external frame part 21 is rotated, the dial plate 42 is rotated about an axis 72 of the pointer 71 together with the external frame part 21 .
[0044] By rotating the dial plate 42 , it is possible to adjust the position of the origin (“0” on the dial plate) to an arbitrary position, and the measurement value of, for example, a master or a block gauge is adjusted to the origin (“0” on the dial plate).
[0045] The cover plate 22 is a transparent disk-shape thin plate. The cover plate 22 may be glass or may be formed of transparent resin such as acrylic resin. The cover plate 22 is fixed to the end face of the external frame part 21 so as to close the opening face of the external frame part 21 .
[0046] In the present embodiment, the cover plate 22 has a front and a rear faces which are flat.
[0047] There is also known a convexly curved cover plate 22 , and the convexly curved cover plate 22 may be used in the present embodiment.
[0048] However, if the cover plate 22 is convex, the scale and the pointer look slightly distorted due to refraction of light. Thus, it is desirable that the cover plate 22 is plane. For example, in precise measurement, in which a scale (graduation) is 0.001 mm, the clearly recognizable difference appears.
[0049] Conventionally, since reflection largely appears and impairs the visibility if a cover plate is plane, a cover plate has been convex to diminish the influence although affected by refraction of light. In this regard, by performing antireflection processing to the cover plate 22 in the present embodiment as described later, it is possible to use a complete plane cover plate 22 which is not affected by refraction of light, and to achieve both of visibility and high-precision measurement.
[0050] The cover plate 22 is subjected to antireflection processing, that is, an antireflection film 24 (AR coating) is formed on the surface of the cover plate 22 .
[0051] The antireflection film 24 may be monolayer or multilayer. Furthermore, the antireflection film 24 may be formed only on the surface of the cover plate 22 or on both of the front and the rear surfaces. The wavelength region or reflectivity of corresponding light is not particularly limited. Actually, these are determined according to a grade or price of a product.
[0052] However, if the antireflection film 24 is not provided, in the case of acrylic resin or the like commonly used as cover plate materials, the reflectivity is about 8%, and a measurer clearly sees a reflection spot 91 by illumination.
[0053] Thus, in order for the measurer not to unconsciously change the posture without caring about a reflection spot at all, the reflectivity of light on the cover plate 22 is to be less than 1%, preferably less than 0.5%, and more preferably less than 0.2%. By providing the antireflection film 24 , the reflection spot is eliminated, and the measurer does not unintentionally change the posture.
[0054] Most of factories use bright illumination for workers' working efficiency or ensuring security. Furthermore, because of high reflectivity of the walls, there are reflection materials, such as a metal member, in many factories. Thus, a factory is an environment in which strong reflection spots easily appear on a plurality of positions of the cover plate 22 , and the positions of reflection spots are greatly changed according to the using place in the factory.
[0055] Note that, when the dial gauge 10 is used, the gauge head does not always face downward, and the dial gauge is mainly used in a lateral posture.
[0056] Furthermore, when products are inspected, the position (graduation) indicated by the pointer 71 is to be a different value in one rotation (360°) according to a workpiece. Although the scale and the pointer 71 are easily seen at the time when the reference point is adjusted firstly, it does not necessarily mean that the scale (graduation) and the pointer 71 are easily seen when a workpiece (object to be measured) is measured. The pointer 71 can be easily seen or difficult to be seen according to the measurement value of a workpiece (object to be measured).
[0057] Thus, variation in measurement values can be caused depending on a measurer, a measurement place, or a workpiece (object to be measured).
[0058] In this regard, since the reflection spots are eliminated by the antireflection film 24 in the present embodiment, the measurer does not unintentionally change the posture.
[0059] Not only when the scale (graduation line) indicated by the pointer 71 is read and but also when the dial plate 42 is rotated to adjust the reference point, the measurer does not unintentionally change the posture.
[0060] Thus, with the dial gauge 10 (measuring device) of the present embodiment, it is possible to stably perform measurement.
[0061] Furthermore, the cover plate 22 has an antifouling film 26 on the antireflection film 24 .
[0062] The antifouling film 26 preferably has water repellency and oil repellency such as fluoro-resin coating.
[0063] In the place where the dial gauge 10 (measuring device) is used, machine oil or cutting oil are used.
[0064] Such oil can be attached to the cover plate 22 by splashing or floating in the air. Furthermore, the cover plate 22 can be unintentionally wiped with dirty hands to clearly see the display part.
[0065] If oil films are attached on some positions of the cover plate 22 , a measurer unintentionally changes the posture to read the pointer 71 or the scale.
[0066] In this regard, by performing the antifouling processing to the cover plate 22 not to get dirty in the present embodiment, the visibility of the pointer 71 cannot be impaired.
[0067] Thus, in a severe environment such as a factory, the visibility of the pointer 71 or the scale is enhanced, and measurement errors caused by parallax are extremely reduced.
Experimental Example
[0068] An experimental example is described below.
[0069] FIG. 4 is a cover plate having a convexly curved surface with no antireflection film.
[0070] The illumination is reflected on the cover plate, the four reflection spots 91 appear.
[0071] FIG. 5 illustrates a cover plate having a flat surface with no antireflection film.
[0072] Although the reflection spot 91 is one, the large and strong reflection spot appears on the surface of the cover plate.
[0073] In contrast, FIG. 6 is an example of the present embodiment.
[0074] There is no reflection spot on the surface of the cover plate, the pointer and the scale are clearly seen although the pointer 71 is positioned anywhere in one rotation.
[0075] Note that, the present invention is not limited to the above embodiment, configurations appropriately changed without deviating from the scope belong to the technical scope of the present invention.
|
A measuring device which reduces reading errors caused by parallax. The measuring device has a gauge head abutting against an object to be measured, and includes a pointer-type display part which displays displacement of the gauge head obtained by being enlarged by an enlarging mechanism and being converted into a rotation amount of a pointer. The measuring device further includes a transparent cover plate provided so as to cover the pointer-type display part, and the cover plate has an antireflection film on the surface. The cover plate further has an antifouling film on the antireflection film. The cover plate has a flat surface.
| 6
|
This is a division of application Ser. No. 018,410, filed Mar. 7, 1979 now U.S. Pat. No. 4,233,036.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to hydrogenating gasification of hydrocarbon-containing raw materials such as oil or coal in a reaction vessel through which the raw material passes while being heated increasingly to above 700° K. and more particularly refers to a new and improved method and apparatus for preventing adhesion or caking during hydrogenating gasification in the reaction vessel.
2. Background of the Invention
Such apparatus for hydrogenating gasification, for instance, is described in German Published Prosecuted Application Number 2 609 320. There, the coal is heated with hot hydrogen for coal gasification counterflow-wise in a reaction vessel to above 700° K. and is partly gasified in the process. The raw material particles in the reaction vessel have a tendency to adhere or cake. To reduce this tendency, oxygen may be added to effect partial combustion of the raw material. This destroys raw materials and also introduces extraneous combustion products in the reaction products. A fluidized bed has been suggested to minimize adhesion or caking of the particles, but this involves more complicated and costly apparatus and operation.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide method and apparatus for preventing adhesion or caking of coal or oil in such a reaction vessel in hydrogen gasification without partial combustion of the raw material used taking place through the addition of oxygen. In this manner, adhesion or caking of the raw material particles can be prevented without using a fluidized bed.
With the foregoing and other objects in view, there is provided in accordance with the invention an apparatus for preventing adhesion or caking of normally liquid and solid hydrocarbon-containing raw materials such as oil or coal in the hydrogenation gasification in a reaction vessel, through which the raw material passes while being heated to a temperature above 700° K., which comprises an enclosed vertical vessel, feed-in means for introducing raw materials in particle form into the top of the reaction vessel wherein it passes down through the reaction vessel, an inlet in the reaction vessel for the introduction of a hydrogencontaining gas at a temperature above 700° K. in admixture with the raw materials to heat the raw materials to a temperature above 700° K. and to effect hydrogenation gasification of part of the raw materials, heating means disposed in the reaction vessel in the path of the downwardly passing particles of raw materials in a temperature zone wherein the downwardly passing particles are at a temperature of about 600° to 700° K., and means for intermittantly heating the surface of the heating means in the reaction vessel to a temperature above 1000° K. to rapidly heat the surfaces of the raw material particles to above 700° K. by direct contact with the heating means alone, in the absence of combustion of raw materials with added oxygen, to cause the raw material particles to become non-caking in its downward passage through the reaction vessel at a temperature above 700° K.
In accordance with the invention, there is provided a method of preventing adhesion or caking of normally liquid and solid hydrocarbon-containing raw materials such as oil or coal in the hydrogenation gasification in a reaction vessel through which the raw material passes while being heated to a temperature above 700° K., which comprises passing raw materials in particle form downwardly through the reaction vessel, introducing a hydrogencontaining gas at a temperature above 700° K. in admixture with the raw materials to heat the raw materials to a temperature above 700° K. and to effect hydrogenation gasification of part of the raw materials, contacting the particles of raw materials as they pass downwardly through the reaction vessel in a temperature zone of about 600° to 700° K. with a medium which is intermittantly at a temperature above 1000° K. in contact with the particles to rapidly heat the surfaces of the raw material particles to above 700° K. by direct contact with the hot medium alone, in the absence of combustion of raw materials with added oxygen, to cause the raw material particles to become non-caking in its downward passage through the reaction vessel at a temperature above 700° K.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a device for preventing adhesion or caking of hydrocarbon-containing raw materials, it is nevertheless not intended to be limited to the details shown, since various modificications may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, however, together with additional objects and advantages thereof will be best understood from the following description when read in connection with the accompanying drawings, in which:
FIG. 1 diagrammatically illustrates a coal gasification plant in which hydrogen gasification is carried out in accordance with the invention.
FIG. 2 diagrammatically illustrates hydrogen gasification of residue oil in a reaction vessel in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
In accordance with the invention, there is provided an intermittently operated heating device in the temperature zone of about 600° K. to 700° K. in the reaction vessel. The heating device has heating means with a surface temperature above 1000° K., so that the surfaces of the raw material particles in the reaction vessel are heated up fast to above 700° K. by contact with the heating means alone without combustion reaction, i.e., without partial combustion of the raw material through the addition of oxygen.
The heating device can consist, for instance, of a heated tube heat exchanger or of steam injection nozzles for steam above 1000° K.
Pertinent embodiment examples will be explained with reference to FIGS. 1 and 2.
In FIG. 1, a coal gasification plant is shown diagrammatically, such as is also described in the mentioned German Published Prosecuted Application No. 2 609 320. The coal is transported via a coal crusher 1 and a conveyor belt 2 into a pre-drier 3, in which it is heated with low-pressure steam entering through steam line 4. The thus pre-dried coal moves from pre-dryer 3 via a solid-material lock 5 into a pressure chamber 6, into which process steam at a pressure of about 60 bar is fed through steam line 7.
This process steam, like the low-pressure steam of the steam line 4, can be taken from a power plant with a pressurized-water reactor. The coal saturated with steam in the pressure chamber 6, is transferred through solid-material lock 8 into an expansion vessel 9 maintained at a lower pressure. The sudden pressure drop induced by the lower pressure in expansion chamber 9 causes fast removal of the steam contained in the coal whereby the coal particles are broken open and their surface is increased considerably.
The coal in the expansion vessel 9, is treated with carbon dioxide entering a carbon dioxide line 10 and forced into expansion vessel 9 by means of compressor 11. The coal from expansion chamber 9 moves through solid-material lock 12 and then, via a conveyor belt 13, into the reaction vessel 14 for the hydrogenating gasification of the volatile components. Although not essential, for smoother operation, a surge feed bin or hopper 49 and another solid-material lock 50 may be interposed between conveyor 13 and reaction vessel 14. Excess gas or vapor carried with the coal may be released through line 51.
The reaction vessel 14 for the hydrogenating gasification is separated from a reaction vessel 16 for steam gasification of the coal by a solid-material lock 15 through which the coal discharges from the reaction vessel 14 into the reaction vessel 16.
A hydrogen-containing hydrogenation gas flows through hydrogen line 17, is heated in a heat exchanger 18, and then enters the lower part of the reaction vessel 14. Process steam at a pressure of about 60 bar is fed from a steam line 19, through a heat exchanger 20 for further heating, and through a steam-oxygen line 21 into the reaction vessel 16. Also, the steam is fed through valve 26 and steam line 22 into two rows of nozzles 23 and 24 arranged on top of each other, and from there into the reaction vessel 14. The product gas obtained leaves the reaction vessel 14 through the gas line 25.
In accordance with the invention, the rows of nozzles 23 and 24 are arranged in a temperature zone of the reaction vessel 14, in which temperatures in the range of 600° to 700° K. occur in the hydrogenating solid-bed gasification. The steam from the steam line 19, superheated in the heat exchanger 20 can now be fed, controlled by means of valve 26, to the steam line 22 and to the rows of nozzles 23 and 24 into the reaction vessel 14. This feeding is always performed if the coal particles are in danger of sticking or caking. Thereby, the surface layer of the coal particles is heated for a short time to above 700° K. and the tendency to cake is thereby nullified.
The tendency to cake may be caused by the kind of change in raw materials or variation in feed rate or temperature as well as other operating conditions. The condition of the particles may be noted as for example by periodically withdrawing samples from the reaction vessel. Heating the surface of the coal particles for a short time, say five minutes or less, preferably less than one minute is generally adequate to prevent caking. The heating is stopped, and if necessary, after a period of time, say five minutes, repeated. Continuous heating is undesirable and indeed may be detrimental by promoting agglomeration of the particles.
The steam escaping from the rows of nozzles 23 an 24 together with the product gas, is drawn off through the gas line 25. In order to completely utilize the coal, oxygen is fed through an oxygen line 27 into the lower part of the reaction vessel 16. Part of the oxygen is branched off from the oxygen line 27 and through a valve 28 enters the steam and oxygen line 21. Ash remaining after the oxidation is discharged from the reaction vessel 16 through a solid-material lock 29 and is carried away on a conveyor belt 30. The gas mixture leaving the reaction vessel 16 through the gas line 31, containing steam, carbon oxides, hydrogen, and methane serves as the heating medium for the heat exchangers 18 and 20 and is processed in a manner known per se in the remaining parts, not shown, of the plant.
FIG. 2 shows diagrammatically a similar arrangement by the example of processing residue oil. In a reaction vessel 32, highly heated (700° K.) residue oil, for instance, is sprayed in, finely distributed, via an oil line 33. A hydrogen line 34 additionally leads into the reaction vessel 32. Part of the hydrogen required is fed to the reaction vessel 32 at a temperature of about 1000° K. via this line. In part 35 of the reaction vessel, the hydrogen is mixed with the residue oil supplied causing some cracking, vaporization of the more volatile constituents of the oil and degradation of relatively non-volatile constituents which assume more the characteristics of carbonaceous solid particles. The mixture which is at a temperature of 700° K. or lower because the higher level heat of the hydrogen is consumed by heat of vaporization and endothermic heat of reaction then flows into heat exchanger tubes 36 which form the middle part of the reaction vessel 32. The heat exchanger tubes are arranged between two perforated plates 37 and 38. In the middle of the heat exchanger tubes 36, there is a partition 39 provided with an opening, for conducting the heating gas. A combustion chamber 40 serves to generate combustion gas for heating the heat exchanger tubes 36. The hot gases leaving the combustion chamber 40 are fed through a gas line 41 into the part of the reaction vessel 32 provided with heat exchanger tubes 36. Through the opening in the partition 39, they pass to an exhaust gas line 43 in the direction of the arrows 42. Contrary to conventional heat exchangers, the heat exchanger tubes 36 are therefore heated in concurrent or parallel flow, i.e., the coldest mixture of oil and hydrogen which leaves part 35 of the reaction vessel 32, comes first into contact with the ends of the heat exchanger tubes 36 which are heated most because the hot gas from line 41 first comes into contact with that end of the heat exchanger tubes 36. In this manner the initially intensive cooling of the mixture of oil and hydrogen will not let the surface temperature of the heat exchanger tubes 36 drop below 1000° K., so that adhesion or caking of oil particles with each other and with the heat exchanger tubes is avoided.
When the oil-hydrogen mixture has reached the perforated plate 38, the additional amount of hydrogen required for hydrogen gasification is fed through the hydrogen line 44 into part 45 of the reaction vessel 32. Because the heat exchanger tubes 36 protrude, uniform mixing of the hot oil-hydrogen mixture with the secondary hydrogen is possible. The reaction vessel 32 is followed by a cyclone 46 for separation of gases and hydrocarbon vapors from non-volatile residue containing coke and carbonaceous materials. These products are discharged from two outlets in cyclone 46, namely, an outlet 47 for the non-volatile residue, and an outlet 48 for the gases and the condensably hydrocarbons produced.
|
Disclosed is a method for preventing adhesion or caking of raw materials such as oil as it is subjected to hydrogenation gasification while being heated to above 700° K. as it passes downwardly through a reaction vessel. The particles of raw materials as they pass through the vessel in a temperature zone of about 600° to 700° K. directly contact a medium at a temperature above 1000° K. to rapidly heat the surfaces of the particles to above 700° K. by direct contact with the hot medium alone, in the absence of combustion reaction, to cause the particles to become non-caking in its further downward passage through the reaction vessel.
| 8
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation part of and claims the benefit of U.S. application Ser. No. 09/613,704 Filed Jul. 11, 2000 now U.S Pat. No. 6,367,328 and a continuation of application Ser. No. 09/613,705, filed Jul. 11, 2000 now U.S. Pat No. 6,363,788, the disclosure of which is incorporated by reference for all purposes.
This application is related to “NONINVASIVE DETECTION OF CORROSION, MIC, AND FOREIGN OBJECTS IN FLUID-FILLED PIPES USING LEAKY GUIDED ULTRASONIC WAVES” by Gorman et al., U.S. Ser. No. 60/143,366, filed Pursuant to 37 C.F.R. 1.71 (e), Applicants note that a portion of this Jul. 12, 1999 and to “NONINVASIVE DETECTION OF CORROSION, MIC, AND FOREIGN OBJECTS IN FLUID-FILLED PIPES USING LEAKY GUIDED ULTRASONIC WAVES” by Gorman et al., U.S. Ser. No. 60/203,661, filed May 12, 2000. This application is also related to “NONINVASVE DETECTION OF CORROSION, MIC, AND FOREIGN OBJECTS IN PIPES USING GUIDED ULTRASONIC WAVES” by Gorman and Ziola, U.S. Ser. No. 60/209,796, filed Jun. 5, 2000 and to “NONINVASIVE DETECTION OF CORROSION, MIC, AND FOREIGN OBJECTS IN PIPES USING GUIDED ULTRASONIC WAVES” by Gorman and Ziola, Ser. No. 09/613,705 filed Jul. 11, 2000. This application claims priority to each of these prior applications, pursuant to 35 U.S.C. §119(e), as well as any other applicable rule or statute.
FIELD OF THE INVENTION
This invention relates to noninvasive testing of the internal conditions of fluid-filled containers such as pipes, cylinders, etc., and to novel ultrasound methods for testing these internal conditions.
COPYRIGHT NOTICE
Pursuant to 37 C.F.R. 1.71 (e), Applicants note that a portion of this disclosure 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 patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
Detecting inner wall corrosion in containers such as pipes, conduits, cylinders, tanks, pressure vessels, etc. has been a longstanding concern in many industries. For example, MIC (microbiologically influenced corrosion) in water systems is of particular concern. Microbes live in water everywhere and are difficult to kill. Corrosion pitting, slimy fluid and rusty nodules are often the products of MIC. Such corrosion and foreign objects cause wall thinning and reduction of flow area that are detrimental to the structural performance of pipes or other containers, and can sometimes lead to disastrous consequences. Chemical, petroleum, water utility, fire and power industries have been battling MIC and other forms of internal container (e.g., pipe) corrosion (e.g., in water and other fluid storage and/or conducting systems) for many years.
Many nondestructive or noninvasive methods have been applied, with varying degrees of success, to locating MIC and assessing its effects. X-ray and gamma ray radiographs provide images that can be used to gauge the presence of MIC, the amount of occlusion and wall thinning. However, drawbacks of these methods include slow inspection speed, high cost and safety/health concern issues.
Ultrasonic thickness gauging is used routinely to measure wall thickness in refinery piping and tanks. Compared to radiography, ultrasound is cheaper and doesn't emit harmful radiation. A single thickness gauge measurement is much faster than radiography, but it only covers a localized area the size of the transducer used in the measurement. Thus, to obtain the thickness information over a large area, the ultrasonic thickness gauge method may not be as fast as radiographic methods. More importantly, a wall thickness reading at a given point depends on good through-thickness echoes so that an accurate time can be measured. Rough corroded internal wall surface and porous MIC nodules make it difficult to get a valid reading. Often the wall thickness reading is greater than nominal. In some cases, no echoes are available because the ultrasonic energy is simply absorbed or scattered. The ultrasonic thickness gauge is not used to detect the existence of, e.g., slimy fluid either.
The present invention overcomes these and other limitations of the prior art by providing new methods, apparatus and integrated systems for measuring features of fluid filled containers (e.g., pipes, tanks, barrels, drums, cylinders, plates and other structures) and a variety of other features that will become apparent upon complete review of the following.
SUMMARY OF THE INVENTION
A “leaky guided wave ultrasound” (LGWU) method is provided for fast and reliable detection of features on the internal walls of containers (e.g., pipes, conduits, tanks, barrels, drums, cylinders, plates and other appropriate structures that will be apparent upon further review of the following), such as container wall irregularities, loss of wall material, pitting, corrosion, MIC, or the like, as well as for the detection of foreign objects, e.g., in fluid-filled containers. Material in the pipes, whether deliberate (e.g., container structural features) or unintended (e.g., ice or foreign objects) can also be detected.
The methods, devices and systems herein are generally applicable to structures and systems that can be configured to comprise one or more gas, solid or fluid. The methods, systems and devices herein are particularly well-suited to structures and systems comprising fluid filled containers.
In the methods of the invention, a transmitting transducer (e.g., placed circumferentially on the outside of the container) excites a guided wave, and part of its energy leaks into a material such as a fluid in a container. The leaking wave travels through the fluid or other material, reflects off the container inner wall and enters the receiving transducer.
The LGWU method measures both the direct field, and the leakage field inside the fluid generated by the guided ultrasonic waves. Since the leakage field interacts directly and, typically, only, with the fluid and inner container wall, the LGWU method is able to reliably detect corrosion, MIC and other features on container inner walls (e.g., the insides of pipes), as well as fluid level and composition, including foreign objects inside the fluid.
By calibrating against the measured direct field, the LGWU method is not sensitive to the container outside wall surface condition, such as the existence of paint, rust or dust. In addition, a single LGWU measurement covers a significant portion of the circumference of the container. Therefore, as few as two or three LGWU measurement locations can provide approximately 100% inspection coverage of an entire container circumference. Thus, the inspection speed is faster than any prior methods. The LGWU method can also be used to accurately detect fluid level (e.g., whether water, hydrocarbon or other fluid type) in the container, or the existence of ice in the container, e.g., due to frozen condensation water.
The present invention also provides devices, apparatus, integrated systems and kits for practicing the methods of the invention. For example, the invention provides an integrated system and/or device for detecting corrosion and MIC on the inner wall of fluid-filled containers such as pipes, foreign objects in the fluid, and/or fluid level using leaky guided wave ultrasound (LGWU).
The system/device includes components for performing the method above, such as a transmitting transducer and a receiving transducer or a single pulse-echo transducer configured for placement at circumferential or longitudinal positions of a fluid-filled container, a wave generator or pulser which produces a shaped tone burst pulse at a specified frequency or uses a resonant transducer excited by a spike or rectangular pulse to create the specified frequency and detection modules consisting of a receiving transducer or transducers connected to both digital and analog amplifiers and filters, analog to digital converters controlled by software or firmware and digital electronic storage media for the purpose of measuring both a direct field and a leakage field, software and/or firmware for analyzing the direct and leakage field signals, thereby providing an indication of existence of corrosion and MIC on the container inner wall, foreign objects inside the fluid and fluid level.
The guided wave can be excited at a selected frequency and angle to maximize the leakage field for selected container ODs and materials. Other suitable wave characteristics can also be selected or modulated in the methods and systems herein; e.g., the amplitude of a given phase point on the tone bursts can be modulated or selected.
The device, apparatus, kit or system can include a computer or computer readable medium having an instruction set for controlling the system e.g., for controlling the transmitting transducer the guided wave generator, or the like. The computer or computer readable medium (or multiple associated computers or computer media) can include other relevant instruction sets, e.g., for measuring the direct field and the leakage field, reporting the results of the measurement to a user, running a graphical display of the relevant results, or the like. Kits can include any of the apparatus or integrated systems elements plus containers for storing the apparatus or system elements, instructions in using the apparatus or integrated systems elements, e.g., to practice the methods herein, packaging, etc.
A presently preferred method/system is to use an arbitrary function generator (which, e.g., generates a pulse at a user-defined frequency) in combination with a wideband transducer, so that a range of frequencies can be excited and received. This approach typically uses computer software to control and shape the pulse and frequency along with wideband amplifiers and filters. The system device includes the geometrical configurations and various media that can be used to couple the transducers to the container, tank or structure.
Further objects and advantages of the invention will become apparent from a consideration of the drawings and description.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a schematic of the LGWU measurement system.
FIG. 2 panels A-C is a schematic of three different ways of implementing the LGWU transducer coupling system 3 and 4 in FIG. 1 .
DETAILED DISCUSSION OF THE INVENTION
List of Reference Numerals
The reference numerals below correspond to elements of the figures.
1 —fluid filled pipe or other container
3 —transmitting transducer coupling system
4 —receiving transducer coupling system
5 —arbitrary function generator
6 —RF amplifier
7 —RF receiver—gain circuitry
8 —RF receiver—filter circuitry
9 —2-channel A/D converter
10 —computer
11 —energy field detection/display module comprising LGWU elements
12 —wedge shoe
13 —water pump
14 —vacuum pump
15 —contact transducer
16 —water bucket
17 —rubber wheel
18 —immersion transducer
19 —Air-coupled transducer
INTRODUCTION: GUIDED WAVE ULTRASONIC TESTING
Guided ultrasonic waves can be used to overcome the speed limitation of a standard ultrasonic thickness gauge. The standard thickness gauge involves a standard “flashlight” beam pulse-echo ultrasonic testing (UT) at a point, with only one transducer being used as both the transmitter and receiver.
In contrast, a guided wave ultrasound (GWU) travels in the areal direction along the axis or circumference of the pipe or other container wall, rather than in the thickness direction. Typically, two transducers placed on the wall surface, several inches apart are used in GWU; one acts as the transmitter and the other as the receiver.
The physics of these different approaches is quite different, as might be expected. Standard UT involves bulk or free waves at wavelengths much smaller than the wall thickness, and the waves can be treated as small tight packets travelling inside the wall in the thickness direction. GWU wavelengths are on the order of the wall thickness or greater, and the wave packets occupy the whole wall thickness and travel in the areal direction along the wall. Thus, the GWU can propagate great distances along the wall area only slightly diminished, like light in optical fibers. Bulk waves propagate without dispersion, while GWU waves are dispersive. In GWU, different frequencies in the wave packet propagate at different velocities and pulses will change shape as they travel along. Finally, instead of the two wave modes as in standard UT, there are many modes in GWU.
The physics of guided waves was described by Lamb in 1917, and Mindlin in the 1950s & 1960s, but little technology in industrial container testing resulted until the early 1990s. As advanced microprocessors made the difficult GWU computations possible, there was an increased interest in the industrial application of GWU.
Currently, there are at least two GWU applications in container testing. The first is the container thickness measurement where the received pulse travels directly from the transmitter to the receiver along the container wall a known distance at a known velocity. Since the spacing between the transmitter and receiver is much greater than the transducer size, the GWU thickness measurement is much faster than the ultrasonic thickness gauge measurement. Note that the GWU wall thickness is an integrated wall thickness over the line between the transmitter and receiver. The other GWU application is for crack detection, e.g., where a single transducer is used as both the transmitter and receiver to listen to the GWU echoes from cracks in the wall. In both cases, the GWU measurements rely on the GWU waves whose energy is distributed through the whole wall thickness.
Since the GWU wave energy is distributed through the entire wall thickness, the GWU method is sensitive to both the container inner and outer wall surface conditions. The sensitivity of the GWU measurement to the outer wall surface can be adjusted by varying the wave mode and frequency selected. Paint and dust have little effect on the measurement due to the large impedance and stiffness mismatch to the container material.
However, the sensitivity of conventional UT and GWU is limited. MIC nodules, slimy fluid and foreign objects in the container can go undetected since they may not affect the waves.
In the present invention, a “leaky guided wave ultrasound” (LGWU) system is utilized. In the system, a transmitting transducer excites a guided wave, and part of its energy leaks into fluid in a pipe or other container. The leaking wave travels through the fluid, reflects off the container inner wall and enters the receiving transducer. The LGWU method measures both the direct field, and the leakage field inside the fluid generated by the guided ultrasonic waves. Since the leakage field interacts directly with the fluid and inner container wall, the LGWU method is able to reliably detect corrosion, MIC and other features on the container inner wall, as well as fluid composition, including foreign objects inside the fluid.
DESCRIPTION OF PREFERRED EMBODIMENTS
It will be understood that the methods and apparatus herein are used for examining, e.g., the inner walls and contents of any type of container (e.g., any fluid filled container). As used herein, the term “container” is intended broadly to apply to any structure that can be said to encompass a given volume, or even to define a portion of a given volume. Such structures include, without limitation, pipes and other conduits, whether partly or fully open or partly or fully closed, tanks, cylinders, plates, pressure vessels, etc. In general, when specifically referring to any of these (e.g., pipes) herein, it will be appreciated that similar methods, apparatus, devices systems, etc., can be applied to any similar structural form.
FIG. 1 shows a basic schematic of a leaky guided wave ultrasound (LGWU) system of the invention. One of skill will recognize a variety of features that may be substituted to achieve essentially similar results; however, for clarity, the following discussion focuses on this basic system.
The system, which interfaces, e.g., with fluid filled pipe or other container 1 , comprises transmitting transducer coupling system 3 , receiving transducer coupling system 4 , RF amplifier 6 , RF receiver gain 7 and filter 8 circuitry, computer 10 with plug-in arbitrary function generator 5 , 2-channel A/D converter 9 , and an energy field detection/display module 11 . The output of arbitrary function generator 5 is connected to the input of RF amplifier 6 . This output is optionally input into channel 1 of A/D) converter 9 to provide a reference signal. The RF amplifier 6 output is connected to transmitting transducer 3 . The receiving transducer is connected to the input of the RF receiver gain 7 and filter 8 circuitry. The output of the RF receiver is connected to the channel 2 input of A/ID converter 9 . Energy field detection/display module 11 controls the signal generation, acquisition and display functions. The energy field detection module optionally comprises an analog to digital converter, which converter converts direct or leakage field energy into digital format data. Arbitrary function generator 5 can, e.g., generate a pulse at a user defined frequency. Energy field detection/display module 11 can be e.g., a software module in computer 10 , or module 11 can be a separate device with software elements.
Software and/or hardware present in energy field detection/display module 11 (this module can include software, firmware, hardware, or a combination thereof, for data analysis and/or display, including analog and/or digital display formats) controls function generator 5 to generate a tone burst pulse with selectable frequency, amplitude, shape, cycles in the pulse and pulsing rate. As noted, the module can include stand alone software or hardware (e.g., dedicated microprocessor hardware), or, commonly, can simply include software present in computer 10 . The shaped tone burst pulse out of function generator 5 is sent to the channel 1 input of A/D converter 9 and displayed on the computer screen (depicted as the upper trace). The same pulse is also sent e.g., simultaneously, to the input of RF amplifier 6 . After amplification, the pulse is then sent to wideband transmitting transducer 3 to excite the guided wave in the container wall. Part of the excited guided wave leaks into the fluid in the form of a bulk wave (leakage field), while the other part continues its propagation along the circumference in the metal wall (direct field). The leakage wave travels inside the fluid, reflects off the inner wall and enters back to the wideband receiving transducer 4 trailing the direct wave. The received signal is then amplified and filtered by gain 7 and filter 8 circuitry of the RF receiver.
The conditioned signal is then sent to channel 2 input of A/D converter 9 , and displayed on the computer screen (depicted as the lower trace). Note that display/software for energy field detection/display module 11 can also define data acquisition parameters such as the A/D rate, total digitized time window, etc. Alternately, these parameters can be controlled separately, e.g., using a different module in computer 10 , or a second computer.
A user can create a calibration wave, using the software, for each container wall thickness, diameter, and material. This wave can be displayed, allowing the user to visually compare the calibration wave with the wave from the container being inspected. This is a helpful component of the system, providing accuracy and reliability when in use by trained personnel. It should be noted that this form of display is novel to the present system.
For pipes or other containers of different OD and wall thicknesses, a specific group of frequencies and transducer coupling systems is selected to maximize the excitation of the leakage field from the well-known leakage theory of guided waves. The frequency range for LGWU wave generation is between about 100 kHz to about 1.5 MHz, with sensor angles between about 45° and about 70° from the normal to the container surface. The amount of the leakage energy is determined, e.g., by the frequency of the ultrasound, properties of the coupling medium and the wall material and thickness. If corrosion exists on the wall inner surface, both the direct and leakage fields are reduced. If there is an obstruction in the container, the leakage energy is reduced due to blockage and scattering. This phenomenon can be used to detect inner wall container features such as corrosion and MIC nodules on the inner wall, or ice due to frozen condensation water (ice which is free in solution can be detected as well, as a foreign object in the fluid), as well as the presence of denser fluids such as slimy fluid (or less dense fluids, such as hydrocarbon-based fluids), the existence of foreign objects in the fluid (ice, dirt, debris, organic matter, rodents, etc.), as well as fluid level in the container. Data analysis/display software for energy field detection/display module 11 analyzes the direct field energy, the leakage field energy and the ratio of leakage/direct field energy, and then classifies the condition of the container (of course, separate software modules can be substituted in place of a single software module).
Generally, the software controls the transmission and reception of the ultrasonic pulse, performs specific analyses to evaluate and categorize the container condition, and displays both raw signals and analysis results in a user friendly format. To measure properly, the type of container is input into a database which can be added to as necessary or desired. This database includes, e.g., the material, schedule and diameter of the container, etc.
A feature of the software optionally provides calibration. For example, by selecting a “CAL” button on the screen, a standard waveform for a new container of that material, schedule and diameter is displayed just above that of the container being tested. This provides the operator with a useful visual comparison to supplement the analysis algorithms. This becomes particularly helpful when the container schedule changes unexpectedly, as it often does, e.g., in older systems that have undergone repairs.
The following provides a basic flowchart/outline of the operations performed by an exemplar software module:
1. Select pipe or other container parameters (schedule and diameter).
2. Select measurement, e.g., thickness or obstruction.
3. Select calibration waveform (this is optional)
4. Acquire data: pulse shape and frequency are downloaded from an internal database; the pulse is sent out of the pulser board in the computer. The pulse is amplified and excites the transmitting transducer. The pulse is detected by the receiving transducer, fed to receiver electronics, and then fed into an analog to digital converter and stored in digital electronic format in the computer.
5. Analyze data: received waveform(s) is/are compared with calibration signal(s) and direct waves are compared to energies of multiple leaky waves as well as the direct wave.
6. Raw data is displayed as received signal(s) and analysis result(s).
7. Stored calibration pulse waveform for good container(s) are displayed.
In general, the LGWU method can be used on pipes or other containers without much surface preparation. For each measurement, the direct and leakage fields cover a significant portion of the container circumference. Therefore, only two or three measurements in the circumferential direction are needed to completely inspect the container inner wall and the fluid inside. Thus, the method can be used to determine the amount of any flow restriction as well as the existence of any occlusion in the container.
To detect fluid level, one moves the transducers axially above or below the fluid level. If the transducers are below the fluid level, the system records the existence of the leakage field. If above the fluid level, the leakage field is absent. For each axial position, a single measurement is sufficient to detect the existence of fluid inside the container (although, of course, multiple measurements can also be made, if desired).
Water-coupled wideband transducers, dry-coupled wideband transducers, and an air-coupled wideband transducer are all examples of appropriate transducers for the present invention. FIG. 2 shows three different ways of implementing LGWU transducer coupling system 3 and 4 in FIG. 1, and many others will be apparent to one of skill, in light of complete review of this disclosure. For the water-coupled system shown in FIG. 2, panel A, contact transducer 15 is mounted on wedge shoe 12 with ultrasonic gel in between. A bottom surface of shoe 12 is machined to match the contour of the container outer surface. In addition, water holes are drilled into the bottom surface. Water tubes are used to connect the water holes to water pump 13 in water bucket/container 16 , and to vacuum pump 14 attached to the side of water bucket/container 16 above water line. Water pump 13 pumps water to the shoe bottom to provide coupling between the wedge shoe and container outer surface. Excess water is sucked up by vacuum pump 14 and flows back into water bucket 16 . For the dry-coupled system shown in FIG. 2, panel B, immersion transducer 18 is placed inside a fluid-filled rubber wheel 17 (it will be appreciated that materials such as polymers, plastics or the like can be substituted for the rubber on the rubber wheel). The wheel rotates while the transducer sits at a fixed angle towards the container. The fluid couples the ultrasound from the sensor to the rubber wheel. The rubber on the outside surface of the wheel deforms to the outside diameter of the container, and is coupled to the container using a small amount of ultrasonic couplant.
An air-coupled system like that in FIG. 2, panel C can also be used. Air-coupled transducer 19 , such as an electromagnetic transducer (EMAT), is placed at an appropriate distance above (or otherwise proximal to) the container.
The coupling system couples ultrasound out of the transmitting sensor and into the container to become guided waves propagating away from the system along the container wall. At the same time, it also couples the ultrasound traveling towards the receiving coupling system into the receiving transducer.
Accordingly, the leaky guided wave ultrasound (LGWU) system provides a fast and reliable device to detect inner wall container features such as corrosion, ice and MIC on the container inner wall, fluidic features such as fluid density and composition, ice, dirt and other foreign objects inside the fluid, and fluid level. These detection abilities are extremely useful in many industrial, commercial and even residential settings, i.e., essentially anywhere fluid filled containers are found. For example, without limitation, fire suppression systems, gas cylinders, water supply and removal (sewage) systems, refineries, water treatment facilities, petroleum supply stations and many others extensively utilize fluid filled containers.
As noted, while the above description contains many specific examples, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of embodiments thereof. Many other variations are possible and will be apparent to one of skill upon review of this disclosure. For example, one can perform the fluid level detection using a more efficient configuration by placing the transducers axially rather than circumferentially. If the transducers are below the fluid level, the direct wave energy is the smallest due to maximum leakage. On the other hand, if the transducers are above the fluid level, the direct wave energy is the strongest due to the absence of leakage. Another example is to apply the same LGWU system to inspect fluid containers of non-circular shapes, such as cubes and cones (i.e., conic and cubic shapes, or any other regular or irregular shapes).
Other uses of the LGWU method include detection of objects or materials inside or behind other structures near or attached to a wall. For example, the trays inside a distillation column, vanes and partitions inside a tank, hat stiffeners in an aircraft wing filled with fuel, reinforcements and other attachments for walls of a fluid container, etc. The advantage of using the LGWU method in those applications is that one can determine whether something is attached to the wall anywhere on the circumference, without having to inspect the entire circumference point by point. This approach is much faster, more reliable and more versatile than standard UT point-by-point methods.
Variations of transducer coupling systems 3 and 4 , other than those specifically described above, can also be used. These include, but are not limited to, dry couplant, laser, electrostatic transducers, air scanners, rollers, touch and release fixtures, back reflected energy with a single transducer etc. Similarly, plug-in function generator 5 can comprise or be replaced by a stand-alone analog function generator, and computer 10 with plug-in A/D converter 9 can also be substituted, e.g., by a digital or analog oscilloscope. The system optionally includes an analog energy detector and analog or digital display.
The foregoing description of embodiments of the invention has been presented for purposes of illustration and description. The description is not intended to be exhaustive or to limit the invention to the precise form disclosed, and many modifications and variations are possible in light of the above teaching. Such modifications and variations which may be apparent to a person skilled in the art are within the scope of this invention. All patent documents and publications cited above are incorporated by reference in their entirety for all purposes to the same extent as if each item were so individually denoted.
|
Ultrasonic energy in the form of guided waves is launched into the wall of a fluid-filled container. The guided wave propagates around the circumference of the container from a transmitting transducer to a receiving transducer. Part of the guide wave energy leaks into the fluid in the form of bulk waves, reflects off the inner wall on the other side and enters back to the receiving transducer trailing the direct wave. Analysis of the received waves determines the presence of corrosion pitting and MIC nodules on the container inner wall, and fluid level. In addition, it determines whether foreign objects are inside the container. The guided waves are created with wideband transducers excited at certain frequencies that depend on the material and geometry of the part being measured. The leakage energy is maximized with a shaped tone burst pulse at the specified frequency. The energy and energy ratio of both the direct and leakage fields are measured and related to the container inner wall condition and the presence of any foreign objects in the fluid.
| 6
|
FIELD OF THE INVENTION
[0001] The present invention relates to silicone rubber compositions, methods for their preparation and uses thereof. In particular, the invention relates to silicone rubber compositions for use in transport, in particular in the aerospace industry.
BACKGROUND TO THE INVENTION
[0002] Silicone elastomers are commonly classified into three main groups of materials: i) room temperature vulcanizing (RTV) elastomers; ii) high consistency rubbers (HCR); and iii) liquid silicone rubbers (LSR). RTV systems are designed to cure at room temperature and HCR systems are designed to cure at temperatures above 100° C. HCR rubbers generally have a very high viscosity in the uncured state. Liquid silicone rubbers (LSR) are so-named because of their low viscosity and paste-like nature in the uncured state. LSR systems are similar to HCR systems in that they are designed to vulcanize at high temperatures. One of the differences between RTV, HCR and LSR elastomers is the molecular mass of the raw materials. Similar amounts of fillers are used in general. The primary distinction, however, is in how the elastomers have to be processed, as a result of their differing physical properties.
[0003] High performance seals are widely used in the aerospace, automobile, marine and oil and gas industries. Aircraft applications in particular represent one of the most demanding sealing environments, with the ultimate in safety-critical requirements. Air frame seals must withstand extremes of temperature and pressure in areas where they are often exposed to high humidity and ozone, friction, high frequency vibration, potentially aggressive chemicals, lubricants and media contamination (e.g. hydraulic fluids, de-icing fluids etc). Airframe seals are used throughout the aircraft body, on wings, windows and doors where they contribute to the aerodynamic efficiency.
[0004] The aerospace industry in particular, but also the marine, automobile and oil and gas industries, is tightly regulated and any high performance seals used in these industries must have the physical properties defined in exacting product specifications.
[0005] Additionally, if a base material is to be used for the manufacture of a seal, such as an airframe seal, it must have the physical properties which allow it to be processed into the required form. Airframe seals in particular can be of large dimensions. Typical manufacturing processes used during the manufacture of a high performance airframe seal are calendering and extrusion. It is important that a composition which is to be used for the commercially viable production of such a seal is capable of being processed using the conventionally used rubber processing equipment, e.g. calendering and extrusion equipment.
[0006] It is known to use HCR silicone elastomers for the formation of airframe seals and in general these elastomers are suitable for use in this conventional rubber processing equipment.
[0007] US 2004/0132890 A1 describes a low specific gravity liquid silicone rubber composition which comprises liquid diorganosiloxane, hydrophobic reinforcement filler, curing agent, hollow resin particles and water. The composition forms a low specific gravity silicone rubber with excellent stability of dimensions in the case of heating and cooling, and the composition is suitable for manufacturing articles such as gaskets used in automobiles and aircraft devices. The hollow resin particles are the essential component for reducing the weight of the silicone rubber composition. The cured rubber is a low viscosity liquid silicone rubber would not be suitable for the production of airframe seals. The LSR cannot be used in the conventional rubber processing equipment used to make airframe seals.
[0008] EP 0 722 999 describes curable organosiloxane compositions for production of abradable seals for turbine-type compressors on aircraft. The compositions comprise a curable polyorganosiloxane, an organohydrogen siloxane, a curing catalyst from metals or compounds of the platinum group and a microsphere reinforcing agent of a particular density to impart machinability and erosion resistance. The curable organosiloxane composition is applied as a protective coating to the inner wall housing of a turbine compressor. The curable organosiloxane composition is necessarily a liquid silicone rubber (LSR) to be applied as a coating. The cured rubber is a low viscosity liquid silicone rubber that is not suitable for the production of airframe seals. The LSR cannot be used in the conventional rubber processing equipment used to make airframe seals.
[0009] U.S. Pat. No. 6,261,214 discloses a non-foamable silicone rubber composition in a heat-fixing roll comprising 100 parts by weight of a thermosetting organopolysiloxane composition and 0.1 to 200 parts by weight of a non-expandable hollow filler having a mean particle size of up to 200 μm, wherein the hollow filler has a true specific gravity of up to 0.5. The organopolysiloxane is preferably a liquid at room temperature and all of the examples disclose a liquid silicone rubber (LSR). The cured rubber is a low viscosity liquid silicone rubber that is not suitable for the production of airframe seals. The LSR cannot be used in the conventional rubber processing equipment used to make airframe seals.
[0010] U.S. Pat. No. 5,981,610 describes a thixotropic liquid silicone rubber composition for injection moulding, comprising an organopolysiloxane, an organohydrogenpolysiloxane, a thixotropic agent, an addition reaction catalyst; and a fine hollow filler (i.e. a micro balloon) having a specific gravity of 0.01 to 0.40 and a mean particle size of up to 300 μm. The fine hollow filler is effective for reducing the weight of a cured part by introducing gaseous cells. The cured rubber is a low viscosity liquid silicone rubber that is not suitable for the production of airframe seals. The LSR cannot be used in the conventional rubber processing equipment used to make airframe seals.
[0000] U.S. Pat. No. 5,262,454 discloses a flame-resistant, curable polyorganosiloxane compound having a content of 2 to 40 weight % hollow glass balls with an outside diameter of up to 200 μm and 3 to 50 weight % of an inorganic intumescent compound which expands at a temperature from 80° to 250° C. It is disclosed that the incorporation of the hollow glass balls in the polyorganosiloxane has a desirable reduction in density and thermal conductivity of the compound. However, the cured compound is stated to be suitable for use in the field of plumbing and building, as well as in the manufacture of windows. There is no indication that the cured compound possesses the properties that would make it suitable for use in an airframe seal, i.e. required hardness and service temperature range.
SUMMARY OF INVENTION
[0011] In the aerospace industry, the performance of the jet engine used in such aircraft has been optimised to such an extent that it has become quite difficult to further improve the fuel economy of the jet engine. Aircraft manufacturers are now looking at other methods to improve the fuel economy of aircraft, one such method being by reducing the weight of the aircraft. It is estimated that over $10,000.00 USD are saved in fuel costs over the life of the aircraft for every kilogram reduction in weight of the aircraft. This has involved the development and use of lighter materials for the construction of the main body fuselage, wings and tail of the aircraft. One area in which there is scope for weight savings is the amount of rubber in a typical commercial aircraft. There are over 600 kg of rubber, including the tyres, in a typical commercial passenger aircraft such as a Boeing 747 or an Airbus 380.
[0012] The inventors have addressed the problem of providing seals, especially airframe seals, which have significantly reduced density in comparison with known aerospace seals, in order to further improve fuel economy, but at the same time achieving the stringent physical properties and performance requirements which are necessary for such seals, in particular those defined in the exacting product specifications required by aircraft manufacturers.
[0013] This has proven to be no easy matter. The inventors have found that in order to achieve this objective it is necessary to select the base composition for use in formation of the seal very carefully. In order to provide a composition which is physically capable of being processed in standard equipment for production of airframe seals and at the same time provide the physical properties required for the end product seal and, further, to provide a significantly reduced density, it is important to choose a defined amount of a hollow filler and a particular class of silicone elastomers for the rubber base.
[0014] Accordingly, according to the invention there is provided a heat curable silicone rubber composition (compound) comprising:
100 parts by weight of an uncured HCR silicone elastomer base which has, when determined in its cured state, a tensile strength of at least 8 MPa, a tear strength at least 18 N/mm, and a specific gravity of between 1.05 and 1.35 g/cc; 0.5 to 30 parts by weight of a hollow filler; 0.1 to 3.0 parts by weight of a curing agent.
The following terminology is used throughout the rest of the specification and should be interpreted as follows:
“elastomer base” refers to the elastomer base in its uncured state without any fillers (e.g. hollow glass balls) or additives “cured elastomer base” refers to the elastomer base in its cured state without any fillers (e.g. hollow glass balls) or additives “cured rubber compound” refers to the elastomer base in its cured state with fillers (e.g. hollow glass balls) and, if present, any other additives in the composition; that is, the cured base corporation
[0021] The term “silicone elastomer” should be interpreted to mean one single silicone elastomer or a combination of silicone elastomers provided that the combination of silicone elastomers amounts to an overall total of 100 parts by weight and has the defined properties.
[0022] Silicone rubber based aircraft seals are manufactured to satisfy specific product specifications. These product specifications define the physical properties of the constituent materials used to make the seal, including fabric reinforcements and the cured rubber. The physical properties defined in a typical rubber specification include but are not limited to: density; hardness; tensile strength; elongation at break; compression set for 24 hours; tear strength; fluid resistance; and resistance to heat ageing.
[0023] The list/use of traditional silicone-compatible compounding ingredients is well documented. Until now the density of a typical fully compounded silicone rubber grade used in the production of an aircraft seal would, dependent on the hardness required, fall in the range 1.1 to 1.35.
[0024] The inventors of the present invention have recognised that it is possible to achieve a desirable combination of low density and the physical properties required for the final seal, as well as providing a composition that can be processed in standard equipment, by selecting as the base elastomer an a HCR silicone elastomer having a tensile strength of at least 8 MPa, a tear strength of at least 18 N/mm and a density of between 1.05 and 1.35 g/cc when in its cured state, and selecting 0.5 to 30 parts hollow filler.
[0025] The incorporation of hollow fillers into the silicone elastomer has the effect of reduction of the density of the silicone elastomer. The hollow fillers create voids in the silicone elastomer, which, when cured, contribute to a reduction in the weight and consequently the density of the cured product. The density of the cured rubber is preferably less than 1 g/cc.
[0026] An advantage of the composition of the invention is that the density of the cured seal material can be reduced to less than 1 g/cc (by utilising hollow fillers having a density between 0.15 and 0.45) but the rubber composition can also meet all of the physical property requirements of the aircraft manufacturers' stringent product specifications.
[0027] The time limit between vulcanization and testing is in accordance with ISO 471, which is incorporated herein by reference. The tensile strength of the cured elastomer base is determined in accordance with ISO 37 Type 2, which is incorporated herein by reference. The tear strength of the cured elastomer base is determined in accordance with ISO 34-1 Method C, which is incorporated herein by reference. The density of the cured elastomer base is determined in accordance with ISO 2781, which is incorporated herein by reference. The elongation at break of the cured elastomer base is determined according to ISO37 Type 2. The curing agent that is used to cure the silicone elastomer for the purposes of determining its properties in the cured state is the curing agent used in the silicone rubber compound (composition) itself. Curing conditions are thus chosen appropriately according to the curing agent, to obtain a fully cured elastomer base. Exemplary curing conditions that can be used are: 10 minutes press cure at 170° C., followed by post cure for 4 hours at 200° C.
[0028] Preferably, the HCR silicone elastomer has a hardness of between 30 and 80 IRHD when in its cured state. The hardness is determined in accordance with ISO 48 Method N, which is incorporated herein by reference. The hardness is preferably, however, not more than 70, in particular not more than 60. This especially useful when it is desired to provide a final cured rubber composition having density of less than 1 g/cc.
[0029] The silicone elastomer is generally an HCR polyorganosiloxane-based silicone rubber base. More preferably, the HCR polyorganosiloxane-based silicone rubber base is a polydimethyl siloxane containing crosslinking groups having hydroxyl, vinyl or hexenyl groups. Alternatively it may be a phenyl substituted poly dimethyl siloxane (polydimethylphenyl siloxane). Phenyl substituted dimethyl siloxanes can give superior low temperature properties in comparison with unsubstituted polydimethyl siloxanes. Even more preferably, the polydimethyl or polydimethylphenyl siloxane rubber base is terminally blocked with hydroxyl, vinyl or hexenyl groups.
[0000] Suitable HCR silicone rubber bases include: Silastic 35U® (a dimethyl vinyl terminated, dimethyl organosiloxane sold by Dow Corning), which has typical properties as follows: a hardness of 33 IRHD, a tensile strength of 9.4 MPa, a tear strength of 22 N/mm, an elongation at break of 894% and a specific gravity of 1.13. The hardness, tear strength, tensile strength, elongation at break and specific gravity of this elastomer base are determined in accordance with the ISO methods mentioned above.
[0030] Silastic TR-55® (a dimethyl vinyl terminated, dimethyl organosiloxane sold by Dow Corning), which has typical properties as follows: a hardness of 55 Shore A (ASTM D-2240), a tensile strength of 1450 psi, a tear strength of 275 ppi, an elongation at break of 775% and a specific gravity of 1.15. The Shore A hardness, tear strength, tensile strength, elongation at break and specific gravity of this silicone elastomer base are determined in accordance with relevant ASTM methods of testing rubber materials.
[0031] In an embodiment of the invention, the hollow filler is selected from the group consisting of glass balls, silica balloons, carbon balloons, phenol resin balloons, vinylidene chloride resin balloons, resin balloons composed of a vinylidene chloride-(meth) acrylonitrile copolymer, alumina balloons, zirconia balloons and shirasu (white sand) balloons or a mixture thereof.
[0032] Preferably, the hollow filler is hollow glass balls. The hollow glass balls preferably have a specific gravity of from 0.15 to 0.45.
[0033] The hollow glass balls are thin-walled but are strong enough such that they are not easily crushed during the manufacture and processing of the curable silicone rubber composition. If the density of the hollow glass balls is less than 0.15 g/cc, a high percentage of breakage may result. If the density of the hollow glass spheres is greater than 0.45 g/cc a higher volume must be added in order to achieve a like-for-like weight saving benefit and would result in an inferior set of physical properties for the resultant material.
[0034] In addition, the external diameter of at least 90% by weight of the hollow glass balls is generally not more than 50 microns. If the average diameter of the hollow glass balls is greater than 50 microns, the possibility of the hollow glass balls being crushed during the manufacturing process is greatly increased. In a preferred embodiment, 90% of the balls by weight have an external diameter of not more than 43 microns, 50% by weight of the balls have an external diameter of not more than 31 microns and 10% by weight of the balls have an external diameter of not more than 20 microns.
[0035] In general, a smaller diameter leads to increased processability, namely lower risk of breakage during the manufacturing process. In addition, a greater number of small glass balls improve the dissipation of stress within the rubber. Preferably then the external diameter of the hollow glass balls is not more than 40 microns. However, for practical purposes the external diameter is usually at least 10 microns, for instance at least 15 microns. In these cases as well, the value refers to the fact that at least 90% of the balls, by weight, have a diameter not more than the specified value.
[0036] The size distribution may be measured by a variety of methods known to the person skilled in the art including, sieve analysis, photoanalysis and laser diffraction. The preferred method of analysis is laser diffraction.
[0037] The glass balls are not necessarily exactly geometrically spherical, but are usually substantially spherical.
[0038] In one embodiment of the curable silicone composition according to the invention, the hollow glass balls comprise 97 to 100 wt % of soda lime borosilicate glass and 0 to 3 wt % of synthetic crystalline-free silica gel.
[0039] Preferably, the curable silicone composition comprises 4 to 6 parts by weight of hollow glass balls.
[0040] In an alternative preferred embodiment, the curable silicone composition comprises 15 to 25 parts by weight of hollow glass spheres.
[0041] The proportion of glass balls used will be determined by the final properties required in the cured rubber, and by the precise characteristics of the glass balls themselves and of the silicone elastomer.
[0042] In a further preferred embodiment, the curing agent is an organic peroxide curing agent selected from the group consisting of 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane, di-tert-butyl peroxide, 2,4-dichlorobenzoyl peroxide, benzoyl peroxide, dicumyl peroxide, tert-butyl perbenzoate, tert-butylperoxy and isopropyl carbonate or any combination thereof.
[0043] Organic peroxide curing agents such as those set out above have been found to be particularly effective in heat curing the silicone rubber composition according to the invention.
[0044] The curing agent can be chosen depending upon the intended process of production of the final seal and the other components of the seal. For instance, fabric-reinforced seals can include various types of fabric and it is important to choose a curing agent whose curing temperature is compatible with the fabric used. For instance, a polyester fabric could not be subjected to temperatures above 170° C. without degradation of physical properties. The skilled person can also choose a curing agent in order to influence other properties, for instance compression set or heat resistance, of the final product cured rubber composition and the seal.
[0045] The curing agent selected must be temperature activated and must confer heat stability to the composition during the curing process and to the cured product. The curing agent selected will depend on the HCR silicone elastomer selected as a base material. The length of time of the cure and the temperature of the cure depend on the curing agent selected. Typically, the cure time will range from 5 to 30 minutes at a temperature of from 100 to 200° C. depending on the curing agent selected. For example, the curing agent 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane has an activation temperature of 165° C. The cure temperature selected for this curing agent is generally 170° C. The cure time will depend on the HCR silicone elastomer selected. The curing agent 2,4-dichlorobenzoyl peroxide has an activation temperature of 100° C. The cure temperature selected for this curing agent is generally 110° C. The cure time will depend on the HCR silicone elastomer selected.
[0046] Preferably, the organic peroxide curing agent is 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane or a combination of 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane and di-tert-butyl peroxide.
[0047] Preferably, the heat curable silicone rubber composition comprises 0.3 to 0.6 parts by weight of the organic peroxide catalyst.
[0048] There are a number of additional components that may optionally be added to the silicone rubber composition according to the invention. Such components can be chosen by the skilled person in order to obtain the required properties of the cured rubber compound and, ultimately, the seal (commonly an airframe seal of which it forms a part).
[0049] In a preferred embodiment, the heat-curable silicone rubber composition according to the invention further comprises up to 1.5 parts by weight of an organosilane coupling agent.
[0050] Organosilane coupling agents—typically containing the general structure (RO) 3 SiCH 2 CH 2 CH 2 —X, where RO is a hydrolysable group, such as amino, methacryloxy, epoxy, etc. can be used. For example for the interaction of silicones and mineral fillers typical examples are alkoxysilanes. Examples are methacryloxypropyltrimethoxysilane, glycidoxypropyltrimethoxysilane, phenyltrimethoxysilane, isobutyltriethoxysilane and propyltrimethoxysilane.
[0051] The organosilane coupling agent must be compatible with the chosen silicone elastomer and the surface of the hollow glass balls. In this regard, it may be necessary to first coat the hollow glass balls with the organosilane coupling agent before incorporating the hollow glass balls into the silicone elastomer. The organosilane coupling agent increases the tensile strength and tear strength of the cured silicone rubber composition. However, its use can reduce the elongation at break in the cured silicone rubber. In this case other additives can be used to offset this decrease.
[0052] Preferably, the organosilane coupling agent is 3-methacryloxypropyl-trimethoxysilane.
[0053] Further preferably, the silicone rubber composition according to the invention comprises 0.08 to 0.12 parts by weight of the organosilane coupling agent.
[0054] In a preferred embodiment, the silicone rubber composition further comprises up to 3 parts by weight of a tensile strength modifier.
[0055] Preferably, the tensile strength modifier is a polyorganosiloxane additive or a reinforcing filler.
[0056] Further preferably, the reinforcing filler is fumed silica or acetylene carbon black.
[0057] Further preferably, the heat curable silicone rubber composition according to the invention comprises 0.7 to 1.4 parts by weight of the tensile strength modifier.
[0058] A tensile strength modifier is added to the silicone rubber composition according to the invention in order to increase the tensile strength of the heat cured product. A scenario may arise where in attempting to maximise the weight savings associated with a reduced density, the cured rubber will meet the hardness requirement of a product specification but may not meet the tensile strength requirement of the product specification.
[0059] The deficiency may be remedied by using an additive in the composition. If the tensile strength is not at the required level, then addition of a tensile strength modifier may remedy the problem.
[0060] High tear strength HCR silicone rubbers tend to have a reduced heat resistance in comparison to general purpose HTV silicone rubbers. Consequently, they would not have been expected, prior to the invention, to be preferred for general use in aircraft seals. However, the inventors have recognised their beneficial properties for use in this application, especially airframe seals, in combination with hollow filters. Accordingly, they are used in the invention and in a preferred embodiment the composition according to the invention further comprises up to 5 parts by weight of a heat stabilising additive. The heat stabilizing additive is added to confer heat stabilizing properties on the composition during the subsequent curing process and on the cured product.
[0061] In a further embodiment of the heat curable silicone composition according to the invention, the heat stabilizing additive is selected from the group consisting of hydrophilic fumed titanium dioxide and ferric based compositions.
[0062] Metal based oxides of polyvalent elements are typically utilised as heat stabilisers of silicone elastomers. Examples of commonly used additives include stannic oxide and titanium dioxide, ferric based heat stabilisers (e.g., red iron oxide or ferric (III) octanoate) and carbon black may also be utilised. Barium zirconate is also used as a stabiliser.
[0063] Preferably, the heating stabilizing additive is hydrophilic fumed titanium dioxide.
[0064] Further preferably, the silicone rubber composition according to the invention comprises 1.8 to 2.3 parts by weight of the heat stabilizing additive.
[0065] In a preferred embodiment, the composition according to the invention further comprises up to 5 parts by weight of a pigment dispersion.
[0066] In a further embodiment of the heat curable silicone composition according to the invention, the pigment dispersion comprises one or more inorganic pigments dispersed in a silicone gum, the inorganic pigments being typically iron oxide based. Generally pigments are supplied as a master batch where the required colour/shades are derived through mixtures/blends of pigments. These pigments are supplied dispersed in a soft silicone gum for ease of incorporation/processing in to the silicone compound itself.
[0067] In a still further embodiment of the heat curable silicone composition according to the invention, the pigment dispersion comprises one or more organic pigments dispersed in a silicone gum, the organic pigments preferably being selected from carbon based derivatives. Generally organic pigments are, like inorganic pigments, supplied as a master batch as above. Acetylene black is the most preferred carbon black used in silicone based compositions as this does not tend to have any detrimental effect on the curing system or the final characteristics of the materials.
[0068] Both the inorganic and organic pigment dispersions are added to the silicone rubber composition according to the invention in order to obtain a desired colour in the final cured product. Usually a light/dark grey colouration is obtained.
[0069] Preferably, the heat curable silicone rubber composition according to the invention comprises 0.30 to 0.70 parts by weight of the pigment dispersion to impart a final desired colour, often light grey.
[0070] In further preferred embodiments, the composition also contains up to 10 parts by weight, of other processing additives. The choice of these depends upon the property required. They can include extending fillers such as ground quartz, diatomaceous earth, calcium carbonate and titanium dioxide; reinforcing fillers as discussed above in connection with tensile strength modification or, most preferably, polytetrafluoroethylene (PTFE). High tear strength HCR silicone elastomers tend to be quite “sticky” in nature. The use of a processing additive like PTFE prevents the pre-cured silicone rubber composition from adhering to the walls of the vessel in which it is mixed. It also provides green strength to the uncured compound, which aids processing/handling. Processing additives such as ground quartz and diatomaceous earth improve the flow characteristics of the mixture.
[0071] Further preferably, the heat curable silicone rubber composition according to the invention comprises 0.2 to 0.4 parts by weight of the process additive.
[0072] One major advantage of the silicone rubber compound of the invention is that it is capable of being processed in the same manner as known silicone based rubber compounds for use in production of seals such as airframe seals. Thus, the methods of preparing the silicone composition/compound itself can be generally conventional (with the addition of steps for the inclusion of the hollow filler). Additionally, and of particular advantage, is the fact that the method of processing the compound to form the final seal can be conventional.
[0073] Thus, there is also provided a method of preparing the heat curable silicone composition according to the invention, said method comprising the steps of:
a) Adding the silicone elastomer to a mixing chamber and mixing the silicone elastomer until the elastomer is suitably homogenised; b) Optionally adding and mixing one or more heat stabilizing additives, organosilane coupling agent, pigment dispersion, tensile strength modifier, processing additive into the silicone elastomer in the mixing chamber; c) Adding and mixing the hollow filler into the silicone elastomer based mixture in the mixing chamber; d) Removing the mixture from the mixing chamber and blending the mixture to obtain a homogenous composition
[0078] wherein the peroxide curing agent is either added to the homogenised silicone elastomer with the pigment dispersion in step b) or is added to the mixture during blending in step d).
[0079] Preferably, the steps a) to c) of the method are performed in a closed mixing chamber preferably having Z-blade rotors.
[0080] These steps of the method are performed in a closed mixing chamber preferably having Z-blade rotors due to the risk of particulate emissions to the atmosphere that may result from the addition of lightweight glass balls if the steps were performed in a conventional open mill. The enclosed mixing process means that the component incorporation accuracy and resultant compound properties can be reliably reproduced between mixed batches, without component loss to the atmosphere or Local Exhaust Ventilation (LEV) systems.
[0081] Preferably, step d) comprises removing the mixture from the mixing chamber to a two roll mill whereupon the mixture is blended until visually homogenous in consistency.
[0082] In one embodiment of the method of preparing the heat curable silicone composition according to the invention, step c) comprises staged mixing. Thus a proportion of the volume of the hollow glass balls is added into the silicone elastomer in the mixing chamber and this is allowed to uniformly disperse before the remaining volume of balls are added. The first portion may constitute from 20 to 70% of the total volume of balls, e.g., from 30 to 60%, for instance about 50%.
[0083] The heat curable silicone rubber composition according to the invention is suitable for use in the preparation of a heat cured silicone rubber having a hardness of between 40 and 80 IRHD, a minimum tensile strength of between 4.0 and 7.0 MPa, a minimum tear strength of between 10 to 12 kN/m 2 , and a density of preferably less than 1 g/cc.
[0084] The heat curable silicone rubber composition according to the invention is also suitable for use in the preparation of a heat cured silicone rubber having a hardness of between 48 and 58 IRHD, a tensile strength of at least 1050 psi, a tear strength of at least 140 lbs/inch and a density preferably of less than 1 g/cc.
[0085] These properties of the cured silicone rubber compound are determined according to the methods given above for the equivalent properties of the cured silicone elastomer base.
[0086] As discussed above, one of the major advantages of the silicone rubber compound of the invention is that it can be processed to form a seal, such as an airframe seal, using standard methods and equipment. Thus, the invention allows the provision of seals having the required final product properties and significantly reduced density without the need for provision of new processing equipment.
[0087] The heat cured silicone rubber based seal can take a variety of shapes and forms depending on the function of the cured product. The shaping and curing process may be any technique known in the art. The two most common techniques in the art are moulding and extrusion. Other standard methods can be used, including calendering. The compositions of the invention have the advantage that they can be used to form seals (often large, shaped seals) by conventional moulding methods. Rubber moulded products are manufactured in a mould to achieve the desired size and shape required. The curable rubber composition is usually placed into a heated mould and cured to obtain the required size and shape under pressure.
[0088] In this regard, there is provided a method of forming a silicone rubber seal, which method comprises the steps of:
a) Moulding the heat curable silicone rubber composition according to the invention to provide the shape of the seal; and b) Heating the composition in the mould (preferably for a time of from 5 to 30 minutes at a temperature of from 100 to 200° C.) in order to vulcanise the composition to a steady state elastomer.
Prior to the moulding step the rubber composition may be combined with a fabric material, in conventional manner for such seals. Extrusion and calendering may be used in the fabrication of the pre-moulded seals.
[0091] Preferably, the composition is heated in the mould for a time of from 5 to 30 minutes at a temperature of from 150 to 180° C. in order to vulcanise the composition to a steady state elastomer.
[0092] The length of time of the cure and the temperature of the cure depend on the curing agent selected. For example, the curing agent 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane has an activation temperature of 165° C. The cure temperature selected for this curing agent is generally 170° C. The cure time will depend on the HCR silicone elastomer selected. The curing agent 2,4-dichlorobenzoyl peroxide has an activation temperature of 100° C. The cure temperature selected for this curing agent is generally 110° C. The cure time will depend on the HCR silicone elastomer selected. The cure time and temperature also depend on the geometry of the seal part being produced. In general the skilled person will select a cure time and temperature so as to produce a fully cured rubber.
[0093] In a preferred embodiment of the method of forming a silicone rubber seal, the composition undergoes post cure processing.
[0094] Preferably, the post cure processing comprises heating the composition for a time of from 3 to 24 hours at a temperature of from 150 to 250° C.
[0095] Even more preferably, the post cure processing comprises heating the composition for a time of from 3 to 5 hours at a temperature of from 195-230° C.
[0096] Even further preferably, the post cure processing is performed in a hot air circulating oven.
[0097] As is conventional, the final seal may be a fabric reinforced seal. Conventional fabrics include polyester, glass fibres, ceramic fibres and polyaramid. The silicone rubber compound is usually combined with or applied to the fabric during or before the moulding step (a) above. Evidently, the subsequent conditions for moulding and curing and any post curing steps will be chosen so as to be compatible with the fabric chosen. For instance, it will be understood that if the fabric is polyester then the processing conditions cannot be above a temperature in which that is degraded.
[0098] There is provided a silicone rubber seal obtainable by the above-described method, wherein the silicone rubber seal has a hardness of from 40 to 80 IRHD, a tensile strength of at least 4.0 MPa (preferably up to 7. MPa), a minimum tear strength of at least 10 kN/m2 (preferably up to 12 kN/m2), and a density of less than 1 g/cc.
[0099] There is also provided a silicone rubber seal obtainable by the above-described method, wherein the silicone rubber seal has a hardness of between 48 and 58 IRHD, a minimum tensile strength of 1050 psi, a minimum tear strength of 140 lbs/inch and a density of less than 1 g/cc.
[0100] The cured product, such as a rubber seal, can be formed by extrusion. The process of extrusion involves processing a heat curable rubber composition through an extruder. There are two main components of rubber extruders: a) the barrel—where the material is softened/pressurized through rotation; and b) a die—the pressure pushes the rubber through the die located at the end of the extruder. The rubber emerges from the extruder in a profile which resembles the die shape. As the possibilities of the die design are almost limitless, so also are the number of possible extruded rubber profiles. After being extruded, depending on the incorporated curative system, the rubber material can be heat-cured using various methods such as an autoclave, hot air tunnels or placing in a mould. As mentioned above, the processing conditions depend upon, for instance, the curing agent chosen, and can be chosen appropriately by the skilled person.
DETAILED DESCRIPTION OF THE INVENTION
[0101] The aerospace, automobile, marine and oil and gas industries are tightly regulated and the components of silicone rubber based seals are subject to stringent product specifications and it is important that a curable silicone rubber composition can meet the product specification.
[0102] The HCR silicone elastomer that forms the base material of the silicone rubber composition has a tensile strength of at least 8 MPa, a tear strength at least 18 N/mm and a specific gravity of between 1.05 and 1.35 g/cc when in the cured state. Preferably, the HCR silicone elastomer has a hardness of 30-80 IRHD and an elongation at break of at least 500%.
[0103] The inventors of the present invention recognised that there is an inverse relationship between the amount of hollow filler added to the HCR silicone rubber base and each of the tensile strength, tear strength and elongation at break, respectively—as the amount of hollow filler increases, the tear strength of the cured product decreases, the tensile strength of the cured product decreases and the elongation at break of the cured product decreases.
[0104] This relationship between the amount of hollow glass balls added and the physical properties of the cured product is used to prepare a heat curable silicone rubber compound having a cured density of less than 1 g/cc but which also meets the desired physical properties recited in a product specification.
[0105] In the invention it is particularly preferred that the specific gravity of the HCR silicone elastomer base is not more than 1.20 g/cc in the cured state. Such elastomer bases are particularly advantageous because they allow the provision of a silicone rubber compound which in the cured state can give a density of less than 1 g/cc.
[0106] One important product specification requires that the cured rubber compound has the following physical properties: a hardness of at least 40 IRHD; a minimum tensile strength of 4.5 MPa; a minimum tear strength of 10 N/mm and an elongation at break of at least 250%.
[0107] To prepare a seal that meets such a product specification, the first consideration is that is that the tensile strength and the tear strength will decrease as the amount of filler increases. The elongation at break will also decrease as the amount of hollow filler increases. Thus, the HCR silicone elastomer selected should have a tensile strength, a tear strength and an elongation at break that is more than the desired tensile strength, tear strength and elongation at break in the cured rubber. For the selected silicone rubber base, the tensile strength will decrease “x” MPa for every 1 part by weight of hollow glass balls, the tear strength will decrease “y” N/mm for every 1 part by weight of the hollow glass balls and the elongation at break will decrease “z” % for every 1 part by weight of the hollow glass balls.
[0108] The second consideration is that the hardness will increase as the amount of filler increases. The HCR silicone rubber base selected must have a hardness that is less than the desired hardness in the cured product. For the selected silicone rubber base, the hardness will increase “w” IRHD for every 1 part by weight of hollow glass balls.
[0109] The scenario may arise where the cured product will meet the hardness requirement but may not meet one or more of the tensile strength, tear strength or elongation at break requirements. In such a scenario, there are several options.
[0110] First of all, the deficiency may be remedied by using an additive in the composition. If the tensile strength is not at the required level, then addition of a tensile strength modifier may remedy the problem. If the tear strength is not at the required level, then addition of a coupling agent may remedy the problem, although care must be exercised in this regard as even though the tear strength will be increased by addition of a coupling agent additive, the elongation at break could be decreased. This can be remedied by the inclusion of further additives.
[0111] Alternatively, the properties of the HCR silicone elastomer can be modified by blending the rubber base with another HCR silicone elastomer that has similar properties with respect to hardness, tensile strength and elongation at break but has, for example, a higher tear strength. The blend of HCR silicone elastomers will have the required hardness, tensile strength, tear strength and elongation at break.
[0112] The curable silicone composition according to the invention is prepared by firstly adding the silicone elastomer to a mixing chamber and mixing the silicone elastomer until the elastomer is suitably homogenised. It has been found that the most efficient mixing chamber is a closed mixing chamber having a Z-blade mixer. However, any mixing chamber that is capable of homogenising the silicone elastomer and mixing the additional components may also be used.
[0113] One or more of the heat stabilizing additive, organosilane coupling agent, pigment dispersion, the tensile strength modifier and the process additive is added to the silicone elastomer in the mixing chamber. The hollow fillers are added to and mixed into the silicone elastomer based mixture in the mixing chamber. Thereafter, the mixture is removed from the mixing chamber and is blended in order to obtain a homogenous composition. The peroxide curative is typically either added to the homogenised silicone elastomer with the pigment dispersion or is added to the mixture during blending.
[0114] The hollow filler may also be added in a stepwise fashion, for instance, adding and mixing 50% of the volume of the hollow filler into the silicone elastomer in the mixing chamber followed by adding and mixing the remaining volume of hollow filler into the silicone elastomer.
[0115] The invention is illustrated by the following examples.
Example 1
[0116] The silicone rubber compound has the following composition (composition A):
[0000] 100 parts by weight of the silicone elastomer S35U;
5.30 parts by weight of thin-walled, hollow, soda-lime borosilicate glass balls having a true density of 0.23 g/cc (available as XLD3000 from 3M); and
2.10 parts by weight of hydrophilic fumed titanium dioxide heat stabilizing additive (available as Aeroxide TiO2 P25 from Evonik Degussa GmbH)
0.10 parts by weight of the organofunctional silane coupling agent 3-methacryloxypropyl-trimethoxysilane (available as Dynasylanmemo E from Degussa
0.80 parts by weight of the organic peroxide curative 2,5-dimethyl-2,5-di-(tert-butylperoxy) hexane (DHBP) (available as DHBP-45-IC2 from United Initiators).
The compound was produced as follows:
[0117] 100 parts by weight of the silicone elastomer S35U (Silastic 35U—an uncatalysed, 35 nominal durometer, high strength polydimethylsiloxane rubber base marketed by Dow Corning) is added to a mixing chamber having a Z-blade mixer. The lid of the mixing chamber is closed and the mixer is started. The S35U elastomer is homogenised by mixing in the chamber for approximately two minutes.
[0118] 0.80 parts by weight of the organic peroxide curative 2,5-dimethyl-2,5-di-(tert-butylperoxy) hexane (DHBP) is added and mixed into the silicone elastomer based mixture, together with 0.40 parts by weight of an inorganic pigment (dispersion of inorganic pigments in a silicone gum carrier available as PD90111 from Silicone Solutions).
[0119] 0.10 parts by weight of the organofunctional silane coupling agent 3-methacryloxypropyltrimethoxysilane are added to 2.10 parts by weight of the heat stabilizing additive hydrophilic fumed titanium dioxide. This mixture is then added to the silicone elastomer based mixture and is mixed for approximately 3 to 4 minutes.
[0120] 50% of the volume of thin-walled, hollow, glass spheres, soda-lime borosilicate glass balls having a true density of 0.23 g/cc and an average diameter of 30 microns (available as XLD3000 from 3M) are added to the silicone elastomer based mixture and mixed for approximately 6 to 8 minutes. The remaining 50% of the hollow, glass spheres are added to the silicone elastomer and mixed for approximately 6 minutes. The mixture is removed from the mixing chamber and transferred to a two roll mill where the material is blended until thoroughly visually homogenous in consistency. Once the required consistency is achieved, the blend is removed from the mill.
[0121] The blend can be either stored indefinitely or can be transferred to a mould in order to produce a rubber seal. The blend is transferred to the mould in order to provide the shape of the seal and then heated in the mould for 10 minutes at a temperature of 170° C. followed by 4 hours at a temperature of 200° C. in order to vulcanise the blend to a steady state elastomer.
[0122] The following table illustrates the physical properties of the cured silicone rubber compound (test methods as per Table 2). The compound was cured by heating for 10 minutes at a temperature of 170° C. followed by 4 hours at 200° C. or 225° C. as shown in the table.
[0123] The weight savings are calculated relative to a commercial product which meets an important product specification. This conventional HCR silicone rubber has a tensile strength of 7.3 MPa, a tear strength of 13.2 N/mm, a specific gravity of 1.18, a hardness of 54 IRHD, an elongation at break of 338%. The service temperature range is from −60° C. to 200° C.
[0000]
TABLE 1
TEST DETAILS
A
Hardness (sheet) IRHD °
48
Tensile Strength MPa
5.3
Elongation @ Break %
565
Tear Strength (1.0 mm nick) N/mm
14.2
Specific Gravity (sheet) ±0.05
0.98
24 hrs @ 150° C. Comp. set %
13.3
Dry Heat Resistance
After 336 hrs @ 200 C.:-
Change in hardness IRHD
+6
Change in tensile strength %
−15.3
Change in elongation @ break %
−24.3
Post Cure detail
4/200° C.
% Weight saving
16.9
[0124] The following table illustrates the physical properties of the S35U silicone elastomer with the organic peroxide curative 2,5-dimethyl-2,5-di-(tert-butylperoxy) hexane (DHBP) (available as DHBP-45-IC2 by United Initiators). 100 parts by weight of the silicone elastomer is mixed with 0.8 parts by weight of the peroxide curative.
[0000]
TABLE 2
TEST DETAILS
S35u
Hardness (sheet) IRHD °
33 (ISO 48 Method N)
Tensile Strength Mpa
9.4 (ISO 37, Type 2
test pieces)
Elongation @ Break %
894 (ISO 37, Type 2
test pieces)
Tear Strength (1.0 mm nick) N/mm
22.0 ISO 34-1 (Method C)
Specific Gravity (sheet) ±0.05
1.13 (ISO 2781)
24 hrs @ 150° C. Comp. set %
10.8 (ISO 813-1 Type B
test specimens Method A)
Dry Heat Resistance
After 336 hrs @ 200 C.:-
Change in hardness IRHD °
+5 (ISO 48 Method M)
Change in tensile strength %
−27.0 (ISO 37, Type 2
test pieces)
Change in elongation @ break
−45.1 (ISO 37, Type 2
test pieces)
Example 2
[0125] A composition is produced as described below.
[0126] 62.8 parts by weight of the silicone elastomer TR-55 (Silastic TR-55—an uncatalysed, 35 nominal durometer, high strength polydimethylsiloxane rubber base available from Dow Corning) and 37.2 parts by weight of the silicone elastomer Silastic 4-2903 (available from Dow Corning) are added to a mixing chamber having a Z-blade mixer. The lid of the mixing chamber is closed and the mixer is started. The TR-55 and Silastic 4-2903 elastomers are homogenised by mixing in the chamber for approximately two minutes.
[0127] 1 part by weight of the silicone bound tensile modifier additive octamethylcyclotetrasiloxane (available as Silastic TM-1 modifier from Dow Corning), and a 0.057 parts by weight of the organic pigment Black MB dispersed in a silicone gum carrier (available as J Black 20 from Dow Corning) are added and mixed into the silicone elastomer mixture.
[0128] 0.3 parts by weight of a PTFE powder processing additive (available as Teflon 6C from DuPont) is added to the mixture in the mixing chamber followed by 18.6 parts by weight of thin-walled, hollow, soda-lime borosilicate glass balls having a true density of 0.35 g/cc (sold as S35 BY 3M) are then added and mixed into the silicone elastomer based mixture.
[0129] The mixture is removed from the mixing chamber and transferred to a two roll mill where 0.7 parts by weight of the organic peroxide curative 2,5-dimethyl-2,5-di-(tert-butylperoxy) hexane (DHBP) is incorporated into the material which is then blended until visually homogenous in consistency. Once the required consistency is achieved, the blend is removed from the mill.
[0130] The blend can be either stored indefinitely or can be transferred to a mould in order to produce a rubber seal. The blend is transferred to the mould in order to provide the shape of the seal and then heated in the mould for 10 minutes at a temperature of 170° C. followed by 4 hours at 200° C. in order to vulcanise the blend to a steady state elastomer.
|
The present invention relates to silicone rubber compositions, methods for their preparation and uses thereof. In particular, the invention relates a heat curable silicone rubber composition comprising: 100 parts by weight of a defined HCR silicone elastomer; 0.5 to 30 parts by weight of hollow filler; and 0.1 to 3.0 parts by weight of a curing agent.
| 2
|
BACKGROUND OF THE INVENTION
The invention relates to transformers and particularly to common mode noise attenuation in transformers in the single phase range of 0.125 KVA to 15 KVA. The invention may also be applied to three phase transformers in ranges up to 45 KVA. The basic transformer has current in the primary that develops a fluctuating magnetic field. The field cuts the turns of the secondary to develop an electromotive force in the secondary. In addition to the desired electromotive force, other components that are not desired also pass over from the primary to the secondary as well as from the secondary to the primary. These undesired components are called noise. For many applications the noise is not objectionable. For many other applications the noise is objectionable and such applications include power supplies for computers and other data processing equipment, medical equipment and other voltage sensitive devices. Problems that may be encountered when such noise is transmitted may include the loss or change of data held in volatile memory or interference with electronic control equipment. For example, noise from a power line may introduce spurious signals into a computer operating system and these signals can be processed as significant data which may result in extra or missing bits which can drastically change the results. Similarly, an important factor is that certain rotating equipment, for example, may impose noise on the power line and this noise may effect other equipment that is connected to that line. Thus it is desirable to minimize both noise transferred from the primary to the secondary of the transformer, as well as from the secondary to the primary. The prior art includes two known methods to achieve high common mode attenuation. The first involves spiral wrapping a coil in a manner similar to a "tire-wrap" using a conductive foil tape. The second uses a shield of relatively thick rigid conductor preformed by a machine into a box-like configuration which slides over the preinsulated coil. Better attenuation is achieved by the first method because the preformed shield is arranged in closer proximity to the coil conductors. The spiral method is, however, undesireable because it is highly labor intensive. The box-like configuration is undesirable because it requires precise dimensioning and tooling, and the shield must be manufactured prior to assembly of the transformer.
The Faraday shield is well known and has been widely used. Applications include the use of a conductive foil placed between coils of the transformer to divert noise to ground. In some cases, capacitance around such a Faraday shield will still couple enough noise from the primary to the secondary to cause problems in very sensitive equipment. It is also known to use variations of the Faraday shield which is essentially a box shield which completely encloses the winding with a conductive foil. The box shield provides a ground path for primary circuit noise and has the advantage that a much smaller capacitance exists between primary and secondary coils than in the case of a simple Faraday shield.
The prior art has used various stamped metallic members which are intended to fit around at least some of the windings of a transformer. Such a prior art approach is shown in the layout view of FIG. 2. It will be seen that known shield involves a relatively complicated pattern which involves difficult assembly onto a transformer winding.
The prior art includes the structures shown in the following U.S. Pats. Nos. 2,978,658 Reaves; 3,983,522 Gearhart; 2,997,647 Gaugler et al; 4,236,133 Seiersen; 3,181,096 Raub; 4,311,977 Owen; 3,717,808 Horna; 4,454,492 Thackray; 3,886,434 Schreiner; 4,554,523 Miki et al; 3,982,814 Kaisrswerth et al; 4,571,570 Wiki et al; 3,278,877 Kameya et al; 3,560,902 Okuyama; 3,678,428 Morris et al; 3,699,488 Goodman et al; 4,042,900 Hinton et al; 4,153,891 McNutt; 4,518,941 Harada.
Of these listed Patents, U.S. Pat. No. 4,042,900 Hinton et al, describes a floating electrostatic shield for disc windings. U.S. Pat. No. 3,699,488 Goodman et al, describes a static shield for each winding section which comprise a strip of aluminum-backed crepe paper. U.S. Pat. No. 4,153,891 McNutt, describes an electrostatic shield assembly for power transformer winding. Similarly, U.S. Pat. No. 4,518,941 Harada, describes two electrostatic shield foils imposed between the primary and secondary windings with an insulator disposed between the electrostatic shield foils. The other patents are only of general interest.
It is an object of the invention to provide effective common-mode noise attenuation without the complexity involved in tooling and stamping a shield such as that prior art shield shown in FIG. 2.
It is an object of the invention to provide apparatus which is inexpensive to manufacture as well as requires a minimum of labor to install.
Still another object of the invention is to provide a shield which is highly effective.
It is an object of the present invention to provide a coil shield which can be fabricated at the assembly floor and does not have to be fabricated by means involving relatively elaborate tooling with precise 4 dimensional controls.
SUMMARY OF THE INVENTION
It has now been found that these and other objects of the invention may be attained in a transformer apparatus which may comprise a core, first and second coils which may each be magnetically coupled to the core, each coil being generally cylindrical and having a circumferential surface and first and second axial extremities. Shielding is disposed around at least the first coil which includes a web shaped metallic, non-magnetic, electrically conductive generally rectangular member. The member has a first portion extending around substantially the entire circumferential extent of the one coil. The member further includes second and third portions extending respectively about a substantial portion of each of the first and second axial extremities.
The second and third portions may include a plurality of slits whereby tab shaped parts may be defined in the second and third portions. Each of the tabs may be substantially rectangular. The member may include nine tabs defined in the second portion and nine additional tabs in the third portion. The first coil may have a plurality of substantially planar faces, the plurality substantially planar faces may intersect along a plurality of lines and the member may be dimensioned and configured with each of the slits being disposed in end abutting relationship to one of the lines. The member may also extend circumferentially around the coil starting at one of the generally planar faces and extends less than a full 360 degrees about the first coil to provide a gap intermediate the ends of the member. In addition, the member may be dimensioned and configured with a gap intermediate two of the tabs proximate to the one planar face. The core may have an E-shaped section which may have first, second and third substantially parallel, substantially coplanar, spaced apart legs and an I-shaped section, the second leg may be disposed intermediate the first and third legs. At least the first coil may be disposed in coaxial relationship with the second leg. Both the first and second coils may be disposed in coaxial concentric relationship with the second leg. The apparatus may include a layer of aramid insulation underneath the member and a second layer of aramid insulation over the member. The member may be aluminum. The member may be less than 15 mils thick. Each of the coils may include a base tube and the base tube has a non-magnetic, electrically conductive metallic covering thereon.
In still another form of the invention the shielding is disposed around both the first and second coils. In some forms of the invention, the member which provides the shielding is exactly rectangular.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be better understood by reference to the accompanying drawing in which:
FIG. 1 is a side elevational view of a shell type transformer in accordance with one form of the invention.
FIG. 2 is a layout of a prior art shield for a transformer.
FIG. 3 is a schematic view of a transformer core, primary and secondary windings.
FIG. 4 is a perspective view of a coil in accordance with the present invention.
FIG. 5 is a partially schematic layout showing the shield construction in accordance with the present invention and more particularly the shield shown in FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1, 3, 4 and 5 there is shown a transformer 10 having a core 12 which in the preferred embodiment is of the type having an E-shaped and I-shaped core in which the windings or coils 14, 16 are disposed in concentric relationship about the center of the three parallel, coplanar legs of the E-shaped core. Because this construction is conventional it has not been shown in great detail.
Referring now to FIGS. 4 and 5 there is shown the shield 18 in accordance with one form of the invention. The shield 18 in the preferred embodiment is manufactured of an aluminum foil having a maximum thickness of about 15 mils. More commonly, it will have a thickness of 9 mils. The shield 18 includes a layer of insulation, a layer of foil and another layer of insulation. The layer of insulation will ordinarily be slightly larger than the foil to avoid electrical creepage. The shield 18 is provided with a plurality of slits 20 which define 9 discrete tabs on a second or upper, as viewed, portion of the shield 18. These nine tabs are respectively identified by the numerals 22, 24, 26, 28, 30, 32, 34, 36 and 38. The dashed line identified by the numeral 39 will be understood to show the fold line for the respective tabs 22-38 and will also define the limit of the second portion. Similarly, the dashed line 41 defines the third or lower portion as viewed, of the shield 18 and thus the upper limit and fold line for the 9 tabs 40, 42, 44, 44, 46, 48, 50, 56, 72, and 74. It will be understood from FIG. 5 that the tabs 22 and 40 are identical in size and shape as are the tabs 24 and 42, 26 and 44, 28 and 46, 30 and 48, 32 and 50, 34 and 72, 36 and 74 as well as 38 and 56. The shield 18 is wrapped around the coil 52 in the manner shown in FIG. 4. More particularly, the coil 52 will be understood to be substantially cylindrical although it may have substantially planar faces and the term generally cylindrical will be used herein to encompass coil forms which have exterior contours which approach or actually are a polygon as well as cores which have an internal contour which is a polygon such as the coil 52 which is shown in FIG. 4 with a rectangular cross section. On one face 54 of the coil 52, the shield 18 is initially installed with the tabs 22 and 40 folded against the respective axial extremities. The shield 18 is dimensioned and configured so that the slits 20 are disposed in end abutting alignment with lines that define generally planar exterior surfaces of the coil 52. Thus, the slits 20, 20 that define the tab 24 are aligned with the lines defining a generally planar section of the coil 52. The same applies for the respective pairs of slits 20, 20 defining the tabs 26, 28, 30, 32, 34, 36 and 38 as well as the slits 20, 20 defining the tabs 40, 42, 44, 46, 48, 50, 52, 54 and 56 which are fixed to the lower, as viewed, axial extremity of the coil 52. As shown in FIG. 4 the tabs 24, 28, 32 and 36 are folded down in the "corner" of the core 52 and are overlapped respectively by the tabs 22, 26, 30, 34 and 38 as shown in FIG. 4. The shield 18 is held in place by adhesive tape (not shown).
To avoid a shorted turn, a gap is left between the ends of the shield 18. More particularly, the shield 18 does not extend a full 360 degrees around the coil 52. The gap is shown in the generally planar section 54 of FIG. 4. It will be further seen that the leads 60, 62 extend axially from the coil 52 intermediate the gap between the tabs 22 and 38. In a similar manner, a gap is provided between the gaps 56 and 40 in the lower axial, as viewed, axial extremity of the coil 52.
Because the material of the shield 18 is relatively easy to work with, there are substantial advantages in terms of ease of installation. Ordinarily the shield 18 will be a non-magnetic, electrically conductive metallic member such as copper, aluminum or tin. The shield 18 includes an inner and outer layer of insulation. Ordinarily this will be layers of Nomex (a DuPont trademark) aramid insulation having substantially the same shape and dimensions as the metallic portion of the shield 18. More particularly, the insulation will have slightly larger dimensions than the metallic portions of the shield 18 to provide an electrical creep distance. In other words the insulating material will extend further along the axial extremity of the coil 52 than does the metallic portion of the shield 18. The shield 18 is connected by a cold-welded aluminum piercing connector which is terminated to the end of a flexible lead wire.
The transformer 10 ordinarily includes two coils such as 52 which are disposed in coaxial concentric relationship. Each coil 52 includes a core former which will be covered by a sheet of non-magnetic, electrically conductive metal which, in the preferred embodiment, is aluminum and will have the same thickness as the shield 18. This sheet does not touch the shield 18 and is also insulated from the inner diametral surface of the coil 52. Ordinarily, this sheet will not be grounded. The shield 18 ordinarily is grounded. As noted above, the term cylindrical has been used herein to describe one form of the coil. It will be understood that the coils may have a square or rectangular cross section or other polygon cross section and the term "generally cylindrical" as used herein should be understood to include such other forms. Similarly, it will be understood that reference herein to a coil having a plurality of generally planar faces encompasses coils that approach a polygon cross section as well as those that have a true cylindrical cross section. Those skilled in the art will recognize that the coils will usually have some form intermediate a circular cross section and a polygon cross section.
|
A transformer apparatus which includes a core and first and second coils which are each magnetically coupled to the core. Each coil is generally cylindrical and have a circumferential surface and first and second axial extremities. Shielding is disposed around at least the first coil comprising a web shaped metallic, non-magnetic, electrically conductive generally rectangular member. The member has a first portion extending around substantially the entire circumferential extent of at least one coil and the member further includes second and third portions extending respectively about a substantial portion of each of the first and second axial extremities.
| 7
|
[0001] This application is a divisional of U.S. application Ser. No. 10/671,883, filed Sep. 29, 2003, the disclosure of which is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention pertains to a method for detecting quinolone-resistant Escherichia coli strains in a biological sample material. The present invention also relates to a kit adapted to perform the present method.
BACKGROUND OF INVENTION
[0003] Bacterial infections are generally treated with antibiotics, among which quinolones have proven to be one of the most highly potent agents for use in human. In the past, fluoroquinolones have been widely used as broad spectrum antimicrobial agents in clinical medicine with the result that bacteria have developed resistance against this agent.
[0004] One of the most concerned species of bacteria to be treated with quinolones is E. coli which causes a number of infections, primarily in and around artificial or natural openings of the body, such as lesions in the skin or the urinary tract. Particularly, experience in and information about the treatment of urinary tract infections shows that 90% of the antibiotics administered are quinolones, while in the meantime about 8% of the E. coli strains have become resistant. Therefore, the ordinary regimen does not apply in a number of cases, which the attending physician will normally recognize only at a later stage of the infection/bacterial growth, with a concurrent destruction of the infested tissue. In addition, quinolone-resistant E. coli may also prove to be a potential threat to neutropenic patients with leukemia, who receive a quinolone as prophylaxis.
[0005] In general, the therapeutic or prophylactic use of quinolones without considering possible resistance of the infecting pathogen may lead to treatment failures as well as to an induction of new resistances.
[0006] Therefore, there is a need in the art to get information about potential resistances occurring in the bacterial population to be treated.
[0007] Up to now the standard methods to determine an antibiotic resistance are based on phenotypic identification, which is time consuming and is in certain cases not sensitive and precise enough.
[0008] An approach in the art to cope with these problems focuses on the investigation of polypeptides accounting for the quinolone resistance in pathogenic bacteria. Several analyses have been developed in order to gain such information, for example a single-stranded conformational polymorphism (SSCP) analysis (Ouabdesselam S, Hooper D C, Tankovic J, Soussy C J, Antimicrobial Agents and Chemotherapy 39 (1995), 1667-70), a mismatch amplification mutation assay (MAMA; Qiang Y Z, Qin T, Fu W, Cheng W P, Li Y S, Yi G., J Antimicrob Chemother 49 (2002), 549-52) and a restriction fragment length polymorphism (RFLP) analysis (Hooper D C, Wolfson J S, Ng E Y, Swartz M N., Am J Med 82 (1987), 12-20).
[0009] However, all the above methods and assays exhibit a variety of different shortcomings. In particular, with a SSCP only the region of mutation may be detected, but not the exact position of mutation. With the MAMA procedure, only one variant may be determined at a time, or else a cost and work intensive multiplex PCR has to be performed. RFLP detects only the position of the mutation, but not the substitution. In addition, none of the methods accurately predicts whether the bacterial sample exhibits resistance to the agents utilized.
[0010] Therefore, a need exists to rapidly and reliably detect the presence of resistant strains of bacteria. Furthermore, such a detection assay should process multiple samples simultaneously and inexpensively.
SUMMARY OF THE INVENTION
[0011] It is, therefore, one object of the present invention to provide a method for detecting the presence of quinolone resistant E. coli strains in a biological sample.
[0012] It is also an object of the present invention to provide micro-arrays and kits for use in detecting the presence of quinolone resistant E. coli strains in a biological sample.
[0013] In accomplishing these and other objects of the invention, there is provided, in accordance with one aspect of the invention a method for detecting the presence of quinolone resistant E. coli strains in a biological sample, which method comprises the steps (i) obtaining DNA from a biological sample, (ii) optionally amplifying the DNA contained in the sample with primers specific for the target sequence, (iii) contacting the DNA contained in the biological sample or obtained in step (ii) with a micro-array comprising at specific predetermined locations of the array two sets of capture probes, which are derived from the sequence of a gyrA gene of E. coli , and comprise the sequence R 1 —(X)—R 2 , wherein (a) X designates all permutations of the triplet at amino acid position 83 and 87 of the gyrA polypeptide of E. coli , and wherein (b) R 1 and R 2 are sequences derived from the gyrA gene of E. coli adjacent to the triplet of either position 83 or 87 of the gyrA polypeptide and comprising of from about 5 to 20 nucleotides, under conditions allowing hybridization of complementary strands, and (iv) determining, at which location on the array binding occurs, wherein a change in the nucleic acid at the said positions resulting in a change of an amino acid is indicative of the development of a resistance against quinolones. In one embodiment, the change in the nucleic acid sequence results in an amino acid change of the gyrA polypeptide to leucine at position 83 and/or asparagine or tyrosine at position 87.
[0014] The invention also provides a micro-array containing at specific predetermined locations of the array two sets of capture probes, derived from the sequence of a gyrA gene of E. coli , comprising the sequence R 1 —(X)—R 2 , wherein (a) X designates all permutations of the triplet at amino acid position 83 and 87 of the gyrA polypeptide of E. coli and (b) R 1 and R 2 are sequences derived from the gyrA gene of E. coli adjacent to the triplet of either position 83 or 87 of the gyrA polypeptide and comprising of from about 5 to 20 nucleotides.
[0015] In another embodiment, there is provided a kit for detecting the presence or absence of a quinolone resistant E. coli strain in a biological sample, containing a micro-array containing at specific predetermined locations of the array two sets of capture probes, derived from the sequence of a gyrA gene of E. coli , comprising the sequence R 1 —(X)—R 2 , wherein (a) X designates all permutations of the triplet at amino acid position 83 and 87 of the gyrA polypeptide of E. coli and (b) R 1 and R 2 are sequences derived from the gyrA gene of E. coli adjacent to the triplet of either position 83 or 87 of the gyrA polypeptide and comprising of from about 5 to 20 nucleotides, and optionally buffers and reagents.
[0016] Other objects, features and advantages of the present invention will become apparent from the following detailed description. The detailed description and specific examples, while indicating preferred embodiments, are given for illustration only since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. Further, the examples demonstrate the principle of the invention and cannot be expected to specifically illustrate the application of this invention to all the examples where it will be obviously useful to those skilled in the prior art.
BRIEF DESCRIPTION OF THE FIGURES
[0017] FIGS. 1 A-D show the results of a hybridization of clinical isolates with labeled target DNA on a micro-array.
DETAILED DESCRIPTION OF THE INVENTION
[0018] In the studies leading to the present invention a number of clinical isolates of Et coil known to be quinolone resistant have been investigated, while it has been surprisingly noted that in contrast to the quinolone sensitive strain, all of the resistant strains exhibited mutations in the gyrA polypeptide in at least one of amino acid positions 83 and 87. This focus on these two amino acid positions in resistant strains has been confirmed by additional studies so that the present invention is essentially based on the finding that in order to detect a quinolone resistance in E. coli , it is sufficient to provide data about these two positions in the gyrA polypeptide of E. coli , only.
[0019] Without wishing to be bound to any theory, it is presently believed that even though these two positions are not the sole mutations occurring in the gyrA polypeptide of quinolone resistant strains, they seem to be mainly involved in the development of resistance due to a folding of the resulting polypeptide preventing interaction with quinolones.
[0020] Another gene of interest that conveys quinolone resistance is topoisomerase IV. Of particular interest is subunit A, which is encoded by the parC gene. In this gene, three amino acid positions, 80, 84 and 87, are proposed as locations for the detection of quinolone resistance.
DEFINITIONS
[0021] In the present description the following definitions apply:
[0022] The terms “micro-array” and “array of oligonucleotides”, which are used interchangeably in the present invention, refer to a multiplicity of different nucleotide sequences attached or positioned on one or more solid supports where, when there is a multiplicity of supports, each support bears a multiplicity of nucleotide sequences. Both terms may refer to the entire collection of nucleotides on the support(s) or to a subset thereof. In one embodiment, the nucleotide sequence is attached through a single terminal covalent bond. The support is generally composed of a solid surface which may be selected from the group consisting of glasses, electronic devices, silicon supports, silica, metal or mixtures thereof prepared in format selected from the group of slides, discs, gel layers and/or beads.
[0023] As used in present invention, the term “probe” or “capture probe” in the sense of the present invention is defined as a nucleotide sequence representing specific parts of the gyrA gene or parC gene, respectively, of E. coli covering amino acid positions 83 and 87 (gyrA) or 80, 84 or 87 of parC, respectively. The sequences have different lengths, e.g. between about 10 and 43 nucleotides, and are either chemically synthesized in situ on the surface of the support or laid down thereon. They are capable of binding to a target nucleic acid of complementary sequence through one or more types of chemical bonds, usually through complementary base pairing, usually through hydrogen bond formation. As used herein, a nucleotide probe may include natural (i.e. A, G, C, or T) or modified bases (7-deazaguanosine, inosine, etc.). In addition, the bases in an oligonucleotide probe may be joined by a linkage other than a phosphodiester bond, such as e.g. peptide bonds, so long as it does not interfere with hybridization.
[0024] The term “target nucleic acid” refers to a nucleic acid, to which the nucleotide probe specifically hybridizes.
[0025] The term “gyrA gene” as used in the present application comprises the gyrA gene of E. coli and its variants due to mutations and changes in different strains.
[0026] The term “parC gene” as used in the present application comprises the parC gene sequence of E. coli and its variants due to mutations and changes in different strains.
[0027] The term “nucleotide sequence” as used herein refers to oligonucleotide(s), polynucleotide(s) and the like including analogous species wherein the sugar-phosphate backbone is modified and/or replaced, provided that its hybridization properties are not destroyed.
[0028] The phrase “hybridizing specifically to” refers to the binding, duplexing or hybridizing of a molecule substantially to or only to a particular nucleotide sequence or sequences under stringent conditions when that sequence is present in a complex mixture of DNA or fragments thereof.
[0029] The terms “background” or “background signal intensity” refers to hybridization signals resulting from non-specific binding, or other interactions, between the labeled target nucleic acids and components of the nucleotide array (e.g., the nucleotide probes, control probes, the array substrate, etc.).
DESCRIPTION
[0030] In order to perform the present method, a DNA from a biological sample is obtained in a first step from an individual to be treated or deemed to harbor a resistant strain. The biological sample/material may be any material supposed to contain a pathogenic E. coli , such as tissue from an area of a lesion, blood, or body secretions, such as sputum or urine. For some applications, it may be appropriate to transfer the biological sample into a medium suitable for the growth of E. coli , e.g. on LB agar plates.
[0031] The DNA contained in the biological sample may liberated from the E. coli cells or isolated according to techniques well known in the art, e.g. via QIAprep® Spin Miniprep Kit protocol (Qiagen, Hilden, Germany). Alternative appropriate methods for obtaining DNA may be chosen, depending on the specific starting material. Such an isolation step assists in preventing the development of extensive background signals during the hybridization step, in case no other selection step is applied.
[0032] In one embodiment, the DNA contained in the biological sample or isolated therefrom may be amplified via a polymerase chain reaction (PCR) using one or more primers, which provides the advantage of augmenting the specific material to be investigated only and also to incorporate a selection step. In case of using one primer only, the complementary strand of the DNA of interest will be synthesized. Alternatively, at least two primers are utilized, allowing an exponential amplification of the material to be investigated. According to an alternative embodiment a nested PCR is carried out, wherein 2 pairs of primers are put to use. A first set of primers is selected to amplify a sequence largely around the target sequence. Then, the second pair of primers are used to amplify a sequence lying within the sequence amplified first. Proceeding accordingly gives the inherent advantage that a second selection step is incorporated in the present method, which assists in reducing the background. After the completion of the PCR reaction, the PCR product may be purified if desired.
[0033] When using an amplification step, the DNA may at the same time be labeled, e.g. by including in the amplification process nucleotides harboring an appropriate label. Alternatively, a label may be attached to the nucleic acid, including, for example, nick translation or end-labeling by attachment of a nucleic acid linker joining the sample nucleic acid to a label.
[0034] Detectable labels suitable for use in the present invention include any composition detectable by spectroscopic, photochemical, biochemical, immunochernical, electrical, optical or chemical means. Useful labels in the present invention include biotin for staining with labeled streptavidin conjugate, magnetic beads (e.g., DynabeadS™), fluorescent dyes (e.g., cyanine dyes, such as Cy5, fluorescein, texas red, rhodamine, green fluorescent protein, and the like), radiolabels (e.g., 3 H, 125 I, 35 S, 14 C, or 32 P), enzymes (e.g., horse radish peroxidase, alkaline phosphatase and others commonly used in an ELISA), and colorimetric labels such as colloidal gold or colored glass or plastic (e.g., polystyrene, polypropylene, latex, etc.) beads. Patents teaching the use of such labels include U.S. Pat. Nos. 3,817,837; 3,850,752; 3,939,350; 3,996,345; 4,277,437; 4,275,149; and 4,366,241.
[0035] In order to allow detection of the presence of a single mutation, the target- or probe-DNA should not be too long, since otherwise renaturation in solution, or base-pairing with a capture probe allowing mismatches may occur. The desired length of such a probe DNA should be of from about 10 to 50 nucleotides, preferably 15 to 40, more preferably 15-30, even more preferred 15-25 nucleotides and may be obtained by either selecting the primers during the amplification step accordingly, or by fragmenting the DNA put to use after an amplification step.
[0036] The target-/probe-DNA thus obtained is then contacted with the capture probes on the micro-array under conditions allowing hybridization of complementary strands only. In general, since a difference in at least one nucleotide is studied under certain conditions, stringent hybridization conditions are selected, e.g. adjusting the hybridization temperature to be about 1′-5° C. below the calculated thermal melting point (T m ) of a the specific sequence at a defined ionic strength and pH. The T m is the temperature (at the defined ionic strength, pH) at which 50% of the probes complementary to the target sequence hybridize to the target sequence at equilibrium. Another possibility to adjust stringent conditions resides in adding destabilizing agents, such as e.g. formamide.
[0037] In principle, the capture probes on the micro-array comprise the sequence R 1 —(X)—R 2 and are provided in two sets on the array. In one set, the sequences R 1 and R 2 , which may be of a length of from about 5 to about 20 nucleotides each, are derived from the sequences of the gyrA gene of E. coli adjacent to the triplet encoding the amino acid at position 83 in the gyrA polypeptide, while in the second set of capture probes the sequences R 1 and R 2 , which may exhibit the same length as indicated above, are derived from the sequence of the gyrA gene of E. coli adjacent to the triplet encoding the amino acid at position 87 in the gyrA polypeptide.
[0038] In a preferred embodiment the sequences R 1 and R 2 are designed such that known mutations of the gene encoding the gyrA polypeptide around positions 83 and 87, e.g. at positions 85 and 89, are taken into account. Hence, the positions 85 and 89 may also be permutated to cover all potential exchanges at these positions and permit an extremely accurate means to determine a SNP at positions 83 and 87, respectively.
[0039] An exemplary set of capture probes (SEQ ID NOS 1-52, respectively, in order of appearance) is shown in table I below.
TABLE I Po- A- si- Varia- mino Name tion tion Sequence (3′→5′) Acid E.coli _GyA83A1 83 85(GTC) AT GGT GAC T A G Stop GCG GTC TA code E.coli _GyA83T1 83 85(GTC) AT GGT GAC T T G Leu GCG GT C TA E.coli _GyA83G1 83 85(GTC) AT GGT GAC T G G Trp GCG GT C TA E.coli _GyA83C1 83 85(GTC) AT GGT GAC T C G Ser GCG GT C TA E.coli _GyA83A2 83 85(GTT) AT GGT GAC T A G Stop GCG GT T TA code E.coli _GyA83T2 83 85(GTT) AT GGT GAC T T G Leu GCG GT T TA E.coli _GyA83G2 83 85(GTT) AT GGT GAC T G G Trp GCG GT T TA E.coli _GyA83C2 83 85(GTT) AT GGT GAC T C G Ser GCG GT T TA E.coli _GyA83AU 83 85(GTI) AT GGT GAC T A G Stop GCG GT I TA code E.coli _GyA83TU 83 85(GTI) AT GGT GAC T T G Leu GCG GT I TA E.coli _GyA83GU 83 85(GTI) AT GGT GAC T G G Trp GCG GT I TA E.coli _GyA83CU 83 85(GTI) AT GGT GAC T C G Ser GCG GT I TA E.coli _GyA87A1 87 85(GTC)/ GCG GT C TAT A AC Asn 89(ATT) ACG AT T G E.coli _GyA87T1 87 85(GTC)/ GCG GT C TAT T AC Tyr 89(ATT) ACG AT T G E.coli _GyA87G1 87 85(GTC)/ GCG GT C TAT G AC Asp 89(ATT) ACG AT T G E.coli _GyA87C1 87 85(GTC)/ GCG GT C TAT C AC His 89(ATT) ACG AT T G E.coli _GyA87A2 87 85(GTT)/ GCG GT T TAT A AC Asn 89(ATT) ACG AT T G E.coli _GyA87T2 87 85(GTT)/ GCG GT T TAT T AC Tyr 89(ATT) ACG AT T G E.coli _GyA87G2 87 85(GTT)/ GCG GT T TAT G AC Asp 89(ATT) ACG AT T G E.coli _GyA87C2 87 85(GTT)/ GCG GT T TAT C AC His 89(ATT) ACG AT T G E.coli _GyA87A3 87 85(GTC)/ GCG GT C TAT A AC Asn 89(ATC) ACG AT C G E.coli _GyA87T3 87 85(GTC)/ GCG GT C TAT T AC Tyr 89(ATC) ACG AT C G E.coli _GyA87G3 87 85(GTC)/ GCG GT C TAT G AC Asp 89(ATC) ACG AT C G E.coli _GyA87C3 87 85(GTC)/ GCG GT C TAT C AC His 89(ATC) ACG AT C G E.coli _GyA87A4 87 85(GTC)/ GCG GT T TAT A AC Asn 89(ATT) ACG AT C G E.coli _GyA87T4 87 85(GTC)/ GCG GT T TAT T AC Tyr 89(ATT) ACG AT C G E.coli _GyA87G4 87 85(GTC)/ GCG GT T TAT G AC Asp 89(ATT) ACG AT C G E.coli _GyA87C4 87 85(GTC)/ GCG GT T TAT C AC His 89(ATT) ACG AT C G E.coli _GyA87AU1 87 85(GTI)/ GCG GT I TAT A AC Asn 89(ATI) ACG AT I G E.coli _GyA87TU1 87 85(GTI)/ GCG GT I TAT T AC Tyr 89(ATI) ACG AT I G E.coli _GyA87GU1 87 85(GTI)/ GCG GT I TAT G AC Asp 89(ATI) ACG AT I G E.coli _GyA87CU1 87 85(GTI)/ GCG GT I TAT C AC His 89(ATI) ACG AT I G E.coli _GyA87A5 87 85(GTC)/ GCG GT C TAT G A C Asn 89(ATT) ACG AT T G E.coli _GyA87T5 87 85(GTC)/ GCG GT C TAT G T C Tyr 89(ATT) ACG AT T G E.coli _GyA87G5 87 85(GTC)/ GCG GT C TAT G G C Asp 89(ATT) ACG AT T G E.coli _GyA87C5 87 85(GTC)/ GCG GT C TAT G C C His 89(ATT) ACG AT T G E.coli _GyA87A6 87 85(GTT)/ GCG GT T TAT G A C Asn 89(ATT) ACG AT T G E.coli _GyA87T6 87 85(GTT)/ GCG GT T TAT G T C Tyr 89(ATT) ACG AT T G E.coli _GyA87G6 87 85(GTT)/ GCG GT T TAT G G C Asp 89(ATT) ACG AT T G E.coli _GyA87C6 87 85(GTT)/ GCG GT T TAT G C C His 89(ATT) ACG AT T G E.coli _GyA87A7 87 85(GTC)/ GGG GT C TAT G A C Asn 89(ATC) ACG AT C G E.coli _GyA87T7 87 85(GTC)/ GCG GT C TAT G T C Tyr 89(ATC) ACG AT C G E.coli _GyA87G7 87 85(GTC)/ GCG GT C TAT G G C Asp 89(ATC) ACG AT C G E.coli _GyA87C7 87 85(GTC)/ GCG GT C TAT G C C His 89(ATC) ACG AT C G E.coli _GyA87A8 87 85(GTC)/ GGG GT T TAT G A C Asn 89(ATT) ACG AT C G E.coli _GyA87T8 87 85(GTC)/ GCG GT T TAT G T C Tyr 89(ATT) ACG AT C G E.coli _GyA87G8 87 85(GTC)/ GCG GT T TAT G G C Asp 89(ATT) ACG AT C G E.coli _GyA87C8 87 85(GTC)/ GCG GT T TAT G C C His 89(ATT) ACG AT C G E.coli _GyA87AU2 87 85(GTI)/ GCG GT I TAT GAC Asn 89(ATI) ACG AT I G E.coli _GyA87TU2 87 85(GTI)/ GCG GT I TAT GTC Tyr 89(ATI) ACG AT I G E.coli _GyA87GU2 87 85(GTI)/ GCG GT I TAT GGC Asp 89(ATI) ACG AT I G E.coli _GyA87CU2 87 85(GTI)/ GCG GT I TAT GCC His 89(ATI) ACG AT I G Capture probes directed against amino acid position 83 and 87 of GyrA with consideration of nucleotide variations at position 85 and 89. All the probes are 19mer and with the SNPs position almost in the middle. Bold letter indicate the SNPs positions and underline letter indicate the positions with variation. For position 83 two sets of probes (eight probes) and for position 87 eight sets of probes (32 probes) were designed, which four sets were directed against the first position of the triplet code, while the other four sets are directed against the second position of the triplet code. Both for position 83 and 87 were universal probes (for position 83 one set and for position 87 two sets) designed, which had inosine at the positions with variations.
[0040] According to a preferred embodiment the array may contain at least one additional set of capture probes, derived from the parC gene of E. coli . In fact, the topoisomerase IV is the secondary target for quinolone in the case of E. coli . The point mutation of the A subunit of this enzyme, which is encoded by parC gene, is the main cause for the resistance. Three amino acid positions, i.e. residues, 80, 84 and 87, have been chosen as locations for the detection, Frequent mutations at position 80 include Ser to Ile or Arg. Common mutations at position 84 include Glu to Lys or Gly.
[0041] As for the set of probes directed to the gyrA mutations also in this set of probes (directed to the parC gene), the capture probes on the micro-array comprise the sequence R 1 —(Y)—R 2 and may be provided in either of one or two or three sets on the array. In one embodiment, the inventive micro-array contains, apart from the capture probes directed to the gyrA gene, capture probes directed to the parC gene. The sequences R 1 and R 2 , which may be of a length of from about 5 to about 20 nucleotides each, are derived from the sequences of the parC gene of E. coli adjacent to the triplet encoding the amino acid at position 80 in the parC polypeptide. In a second and third set of capture probes, respectively, the sequences R 1 and R 2 , which may exhibit the same length as indicated above, are derived from the sequence of the gyrA gene of E. coli adjacent to the triplet encoding the amino acid no. 84 or 87 in the parC polypeptide.
[0042] In a next step it will be determined at which location on the array binding occurred, which is generally achieved by detecting the label that has been attached to/incorporated in the target-DNA prior to the hybridization step, or by performing a labelling reaction on the array. So called “direct labels” are detectable labels that are directly attached to or incorporated into the target (sample) nucleic acid prior to hybridization. In contrast, so called “indirect labels” are joined to the hybrid duplex after hybridization. The indirect label may also be attached to a binding moiety that has been attached to the target nucleic acid prior to the hybridization. For a detailed review of methods of labelling nucleic acids and detecting labelled hybridized nucleic acids see Laboratory Techniques in Biochemistry and Molecular Biology, Vol. 24. Hybridization With Nucleic Acid Probes, P, Tijssen, ed. Elsevier, N.Y., (1993)).
[0043] Also, the capture probes present on the array may contain a label at their 3′-end. After binding of the target DNA, the DNA/DNA hybrids are then cleaved with a particular enzyme thus releasing the label from those capture probes, where the target DNA had bound. Therefore, in this embodiment the decrease in signal is representative of the presence of a given nucleotide sequence in the gyrA gene.
[0044] Means of detecting labeled target nucleic acids hybridized to probes are well-known to those skilled in the art.
[0045] Two types of divergent results may be obtained.
[0046] On the one hand it may be noted that at the location representing the triplet of the native, i.e. quinolone sensitive strain, binding occurred which will be indicative of a quinolone sensitive strain.
[0047] On the other hand it may also be observed that binding occurs on a location representing a triplet different from the native one. In this case, it should be first determined whether the change in the triplet has led to a change in the respective amino acid, either in one or two of the positions, preferably from serine to leucine (at position 83) and/or aspartate to asparagine or tyrosine at position 87.
[0048] This step of evaluating whether the mutation has led to a change of an amino acids may also be obviated by spotting only such kind of mutations on the array which also lead to a change of an amino acid (cf. wobble hypothesis). However, proceeding accordingly harbors the disadvantage that in such a case no signal will be obtained for this position, wherein the skilled person has to rely solely on the positive control to be ascertained that the experiment really worked. For this reason, a micro-array harboring all of the possible mutations of the respective triplets in the corresponding sets is preferred for use in the present method.
[0049] The present method, therefore, provides a reliable and rapid means for determining, whether or not a given biological sample contains an E. coli strain, having developed resistance against quinolones. Since the assay is easy to carry out an attending physician may quickly obtain the required information and may apply an appropriate regimen
EXAMPLE
Micro-Array for Detection Quinolone-Resistant Escherichia coli
[0000] 1. Biological Material
[0050] A total of 29 quinolone-resistant E. coli clinical isolates from four different hospitals in Germany and one quinolone-sensitive clinical isolate were used in this study. These strains have been isolated from urine (n=20), swab (from the lower leg n=1, foot n=1, throat n=2, groin n=1, abscess n=1, unknown n=1) (n=7), secretion (tracheal secretion n=1, bronchial secretion n=1) (n=2) and blood (n=1) of patients. The susceptibility of the strains against quinolone was determined either by using Ciprofloxacin (n 23) alone or by using both Ciprofloxacin and Levofloxacin (n=7). Genomic DNA was isolated using QIAamp DNA Mini Kit (Qiagen) according to protocol provided by the manufacturer.
[0000] 2. DNA Sequencing and Amplification
[0051] The gyrA gene of some isolates was sequenced by amplifying the gene from the isolates using primers that yielded overlapping fragments. The sequencing of 5 isolates gave the preliminary result that apart from a variety of different mutations all of them had a common mutation at position 83 and 87 in the gyrA gene.
[0052] In order to verify the initial finding the region in the gyrA gene, a 417 bp long fragment from nucleotide position 119 to 535 around these positions was amplified by using the following primers:
[0053] forward primer Gyr_coli_F1 (5′-ccatacctacggcgataccg-3′) (SEQ ID NO: 53), and
[0054] reverse primer Gyr_coli_R1 (5′-gcctgaagccggtacaccgt-3′) (SEQ ID NO: 54).
[0055] The PCR mixtures (50 μl) included about 80 ng template of genomic DNA of E. coli ), 0.4 μM (pmol/L) of each primer, 0.25 mM dNTPs (desoxyribonucleoside-5′-triphosphate), 1.5 mM Mg 2+ (mmol/L) and 2.5 U Taq Polymerase (Eppendort). The PCRs were performed in a thermocycler (Eppendorf) using following parameters: 94° C. 5 min; 94° C. 1 min, 52° C. 1 min, 72° C. 1 min for 30 cycles; final elongation 72° C. 10 min. The amplified fragment, which was purified using QIAquick PCR purification kit (Qiagen) according to the manual provided by the manufacture, was used for direct sequencing. The sequencing was done using the same primer pairs with big-dye terminator cycle sequencing kit (Applied Biosystem) and Prism™ 377A-DNA-sequencer (Applied Biosystems).
[0056] For all the investigated resistant strains it was noted that they exhibited a mutation at positions 83 and 87, which were at position 83 from serine (codon TCG) to leucine (codon TTG) (n=28) and at position 87 from aspartate (codon GAC) to asparagine (codon AAC)(n=27) or to tyrosinie (codon TAC) (n=1) or to glycine (codon GGC) (n=1). It was also noted that these 30 isolates belong to two variants. The one variant (n=27) had at position 85 codon GTT (Val), at position 91 codon CGT (Arg) and at position 100 codon TAC (Tyr). The other variant (n=3) had at position 85 codon GTC (Val), at position 91 codon CGC (Arg) and at position 100 codon TAT (Tyr).
TABLE 2 Posi- Posi- Posi- Posi- Posi- Number tion tion tion tion tion of 83 85 87 89 100* Isolate Phenotype TCG GT T GAC CG T TA C 1 sensitive (Ser) (Asp) TTG GT C AAC CG C TA T 3 resistant (Leu) (Asn) TTG GT T AAC CG T TA C 24 resistant (Leu) (Asn) TTG GT T TAC CG T TA C 1 resistant (Leu) (Tyr) T C G GT T G G C CG T TA C 1 resistant (Ser) (Gly) Bold letter indicate the nucleotide change, which lead to amino acid substitution (mutation) and underline letter indicate nucleotide change, which have no effect on amino acid (variation). Asterisk indicate that the sequences of this position were determined by sequencing; Genotype of 30 clinical isolates determined using micro-array. The phenotype was determined by using Ciprofloxacin alone or by using both Ciprofloxacin and Levofloxacin.
3. Array Fabrication
[0057] The possibility of using a micro-array to enable high through-put analysis was evaluated. Using Microgrid II (Biorobotics), 20 μM or 40 μM oligonucleotide capture probes (cf. table 1), which have been dissolved in 50% (Vol./Vol.) in DMSO, were spotted on poly-L-lysine slides (Sigma) in two subarrays. Each slide was also spotted with spotting control (5′-Cy5-tctagacagccactcata-3′) (SEQ ID NO: 55) (Cy5 labeled oligonucleotide), hybridization control (5′-gattggacgagtcaggagc-3′) (SEQ ID NO: 56) oligonucleotide with unrelated sequence referring to gyrA, whose Cy5 labeled complement oligonucleotide would be included in hybridization solution) and process control (5′-taatgggtaaataccatcc-3′) (SEQ ID NO: 57) oligonucleotide with consensus sequence of gyrA). After spotting, the slides were irradiated with UV light at 120 mJ/m 2 using UV crosslinker (Biometra) and blocked using an aqueous blocking solution (0.18 M succinic anhydride in methyl-pyrrolidinone/44 mM Na-borate pH 8.0) for 10 min, followed by rinse in distilled water and subsequently in 100% ethanol, and finally dried for about 10 min,
[0000] 4 Amplification and Labeling
[0058] An amplification of target DNA an concurrent labeling was performed using the following primers:
[0059] Forward primer GyrA_coli_F3 (5′-acgtactaggcaatgactgg-3′) (SEQ ID NO: 58); and
[0060] reverse primer GyrA_coli_R3 (5′-agagtcgccgtcgatggaac-3′) (SEQ ID NO: 59).
[0061] The 50 μl PCR mixture included about 80 ng template (genomic DNA of E. coli ), 0.4 μM (pmol/L) of each primer, 0.1 mM dATP, 0.1 mM dGTP, 0.1 mM dTTP, 0.06 mM dCTP, 0.04 mM Cy5-dCTP, 1.5 mM Mg 2+ and 2.5 U Taq polymerase (Eppendorf). The PCRs were performed in a thermocycle (Eppendorf) using the same parameters as described before. The amplified 189 hp fragment, which was purified using QIAquick PCR purification kit (Qiagen) according to the manual provided by the manufacture, was used for hybridization.
[0000] 5. Hybridization, Washing and Scanning
[0062] The purified amplicon in 40 μl hybridization solution (6×SSPE) plus 0.1 pmol Cy5 labeled DNA for the hybridization control were incubated on the slides prepared as above at 45° C. over night in a hybridization chamber (Corning) or alternatively three hours in a hybridization station. For manual hybridization 4 pmol target DNA was used, while for hybridization in a hybridization station 0.78 pmol target DNA was used. After hybridization, the slides were washed with 2×SSC, 0.1% (w/v) SDS for 15 min, with 0.2×SSC for 3 min at room temperature and dried with N 2 . For detection slides were scanned using Array Scanner GMS 418 (Affymetrix) at Cy5 channel. The images were analyzed using ImaGene (BioDiscovery) and saved as plain-text file as raw data.
[0063] The results obtained by means of the array correspond to the results achieved by means of sequencing. The present method, therefore, provides an efficient means to rapidly, i.e. within about there to 5 hours, determine the presence or absence of a quinolone sensitive or resistant strain.
[0000] 6. Hybridisation of Labelled Target DNA of Clinical Isolate on Microarray
[0064] To further demonstrate the applicability of the claimed invention, a micro-array was designed to evaluate position 83. An array was prepared with the capture probes depicted in Table 1 for position 83. The layout of the probes is depicted in FIG. 1 (A). Two variants were used: GTC at position 85 for variant 1, and GTT at position 85 for variant 2. The results are depicted in FIG. 1 . Panel (B) depicts a quinolone-sensitive E. coli , while panels (C) and (D) show two different E. coli variants with quinolone resistance.
|
The present invention pertains to a method for detecting quinolone-resistant Escherichia coli strains in a biological sample. The present invention also relates to a kit adapted to perform the inventive method.
| 2
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of pending application Ser. No. 08/389,804 filed Feb. 16, 1995.
FIELD OF THE INVENTION
[0002] The present invention relates to installations for the treatment of at least one fluid, of the type comprising at least one receptacle defining a non-vertical portion of a fluid path through at least two masses of adjacent particulate material disposed in the receptacle.
BACKGROUND OF THE INVENTION
[0003] Installations of this type find widespread application in the art, with particulate materials such as catalysts and/or adsorbents. In most of the these uses, obtaining optimal performance depends on the constant thickness of each mass of particulate material in the direction of fluid flow, which is to say the geometric precision of the interface between two adjacent layers. Until now, particularly in installations with masses of concentric different adsorbents, this interfacial precision requires the emplacement, which is delicate and difficult, of an intermediate grid, as described in EP-A-0.118.349.
SUMMARY OF THE INVENTION
[0004] The present invention has for its object to provide a simplified installation for the treatment of fluid, with considerably reduced capital costs and offering great flexibility of use and numerous possibilities for optimization.
[0005] To do this, according to one characteristic of the invention, the two adjacent masses of particulate material are in direct contact with each other in an interfacial region, typically substantially vertical, substantially flat or preferably substantially cylindrical.
[0006] In the present invention, by “direct contact in an interfacial zone”, is intended an interfacial zone without mixing, or with slight mixing for a slight depth, free from any wall or partition interposed between the two adjacent masses.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention has for another object industrial uses of such installations, particularly for the treatment of air flow, for example the drying and/or separation of at least one gaseous constituent of an air flow.
[0008] Other characteristics and advantages of the present invention will become apparent from the following description of embodiments given by way of non-limiting example, with respect to the accompanying drawings, in which:
[0009] [0009]FIG. 1 is a schematic vertical cross-sectional view of an installation for treatment according to the invention in the course of loading according to one embodiment of the installation;
[0010] [0010]FIG. 2 is a schematic perspective view of the double pouring device of FIG. 1;
[0011] [0011]FIGS. 3 and 4 are views similar to FIG. 1 showing modified embodiments of the invention;
[0012] [0012]FIG. 5 is a schematic plan view of another embodiment of the invention;
[0013] [0013]FIG. 6 is a schematic cross-sectional view of an installation according to FIG. 5;
[0014] [0014]FIG. 7 is another alternative embodiment of an installation according to the invention;
[0015] [0015]FIG. 8 depicts a container in the completely filled configuration; and
[0016] [0016]FIG. 9 depicts a container at the start of filling.
DETAILED DESCRIPTION OF THE INVENTION
[0017] In the description which follows and the drawings, identical or analogous elements bear the same reference numerals, primed as may be.
[0018] In FIG. 1 there is shown a receptacle 1 of an installation for purification by adsorption of the type described in EP-A-0.118.349 mentioned above, defining an internal closed volume with a vertical axis divided internally by a tubular central grid 2 and a tubular concentric peripheral grid 3 into a central volume 4 , an annular intermediate volume 5 , and a concentric annular peripheral volume 6 , the annular intermediate volume 5 being filled with at least one, and in this case two masses of adsorbent A, B, traversed successively by the gas flowing radially between the volumes 4 and 6 and, according to the invention, having no intermediate grid. For the purification of air before its distillation or for the separation of air by so-called adsorption techniques by pressure variation (PSA or VSA), the adsorbents A and B are generally constituted of particulate materials that differ from each other according to their composition and/or their granulometry, typically of particles of alumina and/or zeolith, respectively.
[0019] In the embodiment shown in FIG. 1, an apparatus for using adsorbent masses A and B according to a process of the present invention comprises two side-by-side diffusing devices 7 and 8 of an overall width less than the radial width of the intermediate volume 5 and secured to a frame 9 comprising drive means, for example rollers 10 bearing radially on the walls of the grids 2 and 3 and driven in rotation by a motor 11 carried by the frame. Each diffusion device 7 , 8 comprises a principal portion forming a particulate material reserve prolonged downwardly and rearwardly in a rear thinner portion terminating in a distribution mouth 12 , 13 , respectively, the lower anterior surface of each device 7 , 8 having for example a profile of a rounded shoe 14 prolonged rearwardly by a horizontal support surface terminating at the pouring mouth 12 , 13 . In the illustrated embodiment, the principal portions of the diffusing devices 7 and 8 are connected by telescopic or flexible conduits 15 and 16 , respectively, to reservoirs 17 and 18 of particulate material supported rotatably at 19 on the upper imperforate end of the central grid 2 . The reservoirs 17 and 18 as well as the diffusing devices 7 and 8 are so dimensioned as to be able to pass through an access opening 20 formed preferably axially in the upper end of the shell of the receptacle 1 , so as to be withdrawn after filling the intermediate volume 5 .
[0020] As will be seen clearly in FIG. 2, each diffusing device 7 , 8 leaves behind it, when it is moved in the direction away from the mouths 12 , 13 , a continuous strip 21 A, 21 B of particulate material having a cross section corresponding to that of the depositing mouth 12 , 13 , and hence of constant thickness. Thus, by turning the diffusing devices 7 and 8 in the intermediate chamber 5 , they deposit at each revolution a layer of two adjacent strips 21 A, 21 B of the same thickness occupying all the radial width of the intermediate volume 5 . With each new revolution, the diffusing devices 7 and 8 , bearing on the layer previously deposited and sliding on this latter, deposit progressively a new layer, so as to build up the height of the intermediate volume 5 , after which the diffusing devices and the reservoirs 17 and 18 are withdrawn and the blocking and/or sealing means are emplaced, at the top of the intermediate volume 5 , to prevent in use local phenomena of bypassing the fluid or fluidization of the masses A and B.
[0021] As will also be seen in FIG. 2, the process for producing an installation according to the invention permits emplacing side by side at least two different adsorbent beds, of different material or of the same material having different granulometries, without having to provide according to the invention any separating or containing grid between the masses of particulate materials. Thus, the simultaneous side-by-side spreading in this embodiment of the strips 21 A, 21 B, of constant controlled thickness, in practice between 1 and 20 cm, avoids problems of sloping at the edges and limits, even with very fluid particulate materials, the problems of mixing between two adjacent strips, this mixing zone being of the order of the width of the slope, which is to say of the order of three times the thickness of the spread strip if spreading is sequential, or a value which is substantially less if the spreading is, as in this preferred embodiment, simultaneous.
[0022] There is shown in FIGS. 3 and 4 embodiments of filling permitting giving freedom from the requirement to deposit simultaneously or semi-simultaneously and using a sliding barrier 30 of low height, therefore disposable in the height of the receptacle at the end of the filling phase and moving vertically with the deposit of the layers of particulate material, thereby achieving, by elimination of the slope, the same precise interface upon sequential spreading or deposition as for simultaneous spreading, as previously described. There is shown in FIG. 3 the two spreading devices 7 and 8 of FIG. 1, here separate and independent, as permitted by the sliding barrier 30 , but synchronized in their operation. A sliding barrier 30 is present in the form of a section of tube disposed concentrically within the space 5 and having an axial height greater than 1.5 times the axial height of the least high mouth ( 13 ) of the spreading devices 7 , 8 , between which it extends. Preferably, the upper end of the barrier 30 comprises a radial flange 31 bearing on a turning member 32 at the top of one of the spreading devices so as to be displaced axially simultaneously with this latter, the other spreading device being actuated in rotation in synchronism with the first.
[0023] The embodiment of FIG. 4 is different from that of FIG. 3 by the fact that the filling of one of the masses of particulate material, in this instance the internal mass B, is here effected by pouring from above, as permitted by the sliding barrier 30 , via a manifold 80 displaced in rotation in synchronism with the deposition, by a spreading device 7 such as described above, of strata of constant thickness according to the processes of FIGS. 1 and 3.
[0024] There is shown in FIG. 5 a device with two sliding barriers for loading three masses of concentric particulate material in the internal volume defined between the interior and exterior grids 2 and 3 . As shown in FIG. 5, the device comprises a rotating device 70 , displaceable axially by being preferably suspended at the top of the receptacle 1 , with three pouring hoppers 71 , 72 , 73 , connected by transverse arms 74 and provided with members that roll or bear with low friction coacting with the radial flanges 31 1 and 31 2 of two concentric tubular sliding barriers 30 1 , 30 2 , separating the volumes of the three concentric adsorbent masses A, B, C. The dispensing hoppers 71 - 73 , fed by supplies turning with the device as in the embodiment of FIG. 1, comprise lower pouring openings 81 , 82 , 83 , opening respectively into the annular spaces between the internal barrier 31 2 and the internal grid 4 , between the barriers 31 2 and 31 1 , and between the external barrier 31 1 and the external grid 3 . After filling the zone between the grids 2 and 3 , the device 10 is demounted and removed from the receptacle 1 through the opening 20 , then the upper volume above the masses A, B, C is at least partially occupied by one or several containing devices for the upper parts of the masses A-C, for example via an inflatable member 40 connectible to a source of gas under pressure.
[0025] As will be understood from the above, the principal technical problem resides in the provision of at least two homogeneous masses of particulate material within the volume confined by the adsorber, more particularly when the masses are annular and concentric: it is necessary thus to maintain the levels of the particulate material within the receptacle volume or in the spreading devices within narrow limits (the height of the successive layers in the modifications according to FIGS. 1 and 2, the height of the sliding barrier in the modifications of FIGS. 3 to 5 , the height of the hopper of the diffusing device). These heights are thus necessarily limited by the need to be able to remove the pouring or spreading devices from the receptacle at the end of filling or to leave them within a volume or within the height of this latter without their impairing the good operation of the installation. It is therefore difficult, apart from installations with receptacles of small dimensions which can be assembled in a factory, to effect the filling of an upwardly open receptacle, which permits the use of at least one sliding barrier having a height greater than a third of that of the grids 2 and 3 , that can be removed after complete filling of the receptacle whose upper end will then be welded or assembled by a ring on the peripheral edge. According to the invention, the flow of each particulate material emplaced within the receptacle must be adapted at all times so as to maintain homogeneous levels. To this end, the pouring/diffusing devices should comprise at least a control means for the flow rate of the particulate material, typically upstream of the spreading device, for example withdrawal devices with valves or lugs, as shown at 51 and 52 in FIG. 1, means for measuring the level of the particulate material in the spreading hoppers, for example, photoelectric cells as shown at 53 and 54 in FIG. 2, or reflective devices, particularly ultrasonic, as shown in 55 and 56 in FIG. 5.
[0026] Represented in FIG. 7 is another alternative embodiment of concentric annular beds in a concentric-bed plant similar to the previous ones. Shown again here are the particulate-material reservoirs 17 and 18 and their rotary support 19 , in this case of the supported-arm type, which are arranged, in this case, outside the container 1 , each discharging via a hose or telescopic pipe 15 , 16 , respectively, into the adjacent annular spaces delimited, in the intermediate annular volume 5 between the perforated walls 2 and 3 , by a shell forming a slip form 30 .
[0027] As may be seen on the left-hand part of FIG. 7, the lower end of each pipe, respectively 16 and 15 , emerges slightly below the upper end of the form 30 and is fastened to the latter, in a disconnectible manner, at 46 . Thus, by discharging a quantity of particulate material greater than the free volume formed by the slip form, this volume is filled until the mass of particulate material is flush with the end of the pipe 15 , 16 , which thus interrupts the filling of the said volume. The discharge is then interrupted by the valves 51 , 52 and the form shell 30 is raised, for example by cables 47 passing through the passages 40 and the openings 41 , 42 , through a height less than the height of the shell itself, that is to say with its lower end still immersed in the previously deposited layers of particulate materials, the lower ends of the pipes 15 and 16 accompanying this movement and remaining in position with respect to the shell 30 for a new charging step.
[0028] In the embodiment in FIG. 7, the pipes 15 and 16 extend through filling orifices 40 formed in the upper wall of the container 1 , vertically in line with the annular space 5 and angularly distributed around the axis of the container 1 , and through openings 41 , 42 formed in deflecting plates 43 and 44 converging typically on each other as a V, leaving an annular passage 45 at their vertex and forming the upper boundary of the active part of the annular beds A and B guiding the flows of fluid, in this zone, through these beds. When the shell 30 , after the end of raising, has reached the level of the deflecting plates 43 and 44 , it is pulled up, in the example shown, through the annular space 45 between the facing ends of these deflecting plates and remains permanently housed in the upper end of the container 1 in the configuration shown by dotted lines at the top of the right-hand part of FIG. 7. The openings 41 and 42 in the plates 43 and 44 are closed off and then reserves of particulate materials are poured in via the shortened pipes 15 and 16 above the deflecting plates 44 , 43 which remain separated by the shell 30 immobilized in its upper position. Filling is completed by discharging the particulate materials directly via the orifices 40 on either side of the shell 30 , after which the pipes 15 and 16 , the reservoirs 17 and 18 and their support 19 are removed, the passages 40 closed off and the container placed in the operational condition.
[0029] In the embodiment in FIG. 8, which represents a container in the completely filled configuration, the slip form 30 includes a gas-“transparent” lower part 30 A, typically in the form of sandwiches of meshes, which does not disrupt the production of a distinct interfacial zone between two contiguous beds. In this case, as shown in the right-hand part in FIG. 8, the said meshed lower part can remain immersed in the operational zone of the beds A and B, beneath the deflectors 43 , 44 . Optionally, as shown in the left-hand part in FIG. 7, the deflectors may be omitted, the upper “solid” part of the form 30 , also immersed in the masses A and B, forming an obstacle and preventing short-circuiting passages of fluid via the top of the beds.
[0030] Illustrated in FIG. 9, which represents a container at the start of filling, is another embodiment of contiguous vertical layers of differentiated materials without a separating screen according to the invention. In this case, the materials are discharged, in synchronism, directly into the annular chambers beneath the filling orifices 40 . These chambers are initially delimited by a shell 33 of defined height, the upper edge of which is fixed to the roof of the container and, permanently, to their lower end, by an annular bottom wall 34 which can slide in a sealed manner along the inner 2 and outer 3 containing screens, and which is retained, during its descent, by cables 47 . The bottom wall 34 is progressively lowered until it ends up resting on the bottom structure of the container 1 , as shown by dotted lines in the lower part of FIG. 9. It will be understood that, in this embodiment, the strata of adjacent beds, formed on either side of the shell 33 “descend” progressively with the bottom 34 , while being maintained contiguous and guided by the screens 2 and 3 . When the container is completely filled, the shell 33 , which extends as far as the upper level of the “let-through” zones of the containing screens 2 and 3 , acts as an anti-bypass baffle, in the manner of the form 30 of the embodiments in FIGS. 7 and 8.
[0031] Although the present invention has been described with respect to particular embodiments, it is not thereby limited but on the contrary is susceptible to modifications and variations which will be apparent to one skilled in the art. Thus, the process of FIGS. 1 and 2 can be used to deposit sequentially parallel strips in vertical non-cylindrical treatment installations, particularly to provide therein a plurality of adjacent masses of particulate materials of small thickness and having different granulometries.
|
An installation for the treatment of fluid comprises a receptacle ( 1 ) defining a non-vertical portion of a path for fluid through at least two adjacent masses (A; B; C) of particulate materials, typically different from each other, each mass being in direct contact with its neighbor or neighbors, without the interposition of a separating grid. The installation is particularly useful for the separation or drying of air.
| 1
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a marking apparatus for printing markings on a substrate, and more particularly to an improvement in an electrostatic print marking apparatus.
2. Description of the Prior Art
It has been proposed by the inventors of the present invention to electrostatically print markings on rolled steel plates. Various kinds of information such as the name of the manufacturer, the destination of shipment, dimensions of the plate and so forth are printed in the form of markings on the successively manufactured steel plates fed out of a rolling mill. In a rolling mill, the rolled steel plates leave the rolling rolls in a heated condition. Therefore, in the process already proposed by the inventors, an intermediate image carrying medium is provided between the steel plate on which marking is to be finally printed and an electrostatic image recording member (drum or belt) so that a toner image formed on the recording member is first transferred to the intermediate image carrying medium and then to the steel plate. Thus, the electrostatic recording portion and the developing portion of the apparatus are protected from heat and mechanical vibration.
In the above described print marking apparatus, a high voltage is applied between the steel plate and the intermediate image carrying medium in order to effectively transfer the toner image from the intermediate image carrying medium to the steel plate. The strength of the electrostatic force effected between the image carrying medium and the steel plate to facilitate the transfer of the toner image is determined by the strength of the electric field and the strength of the charge carried by the toner particles. Therefore, the higher is the strength of the charge carried by the toner particles, the easier it becomes to transfer the toner image to the steel plate. Further, when the toner particles are sufficiently charged, the toner particles are prevented from scattering widely over the steel plate and accordingly the resolution of the image obtained on the steel plate is improved. The high voltage applied between the steel plate and the intermediate carrying medium in the above described print marking apparatus enhances the sharpness of the image obtained on the steel plate.
Nevertheless, as the toner image is transferred twice in the above described print marking apparatus, this apparatus suffers from a defect in that the charge of the toner particles is neutralized or weakened in the first transfer process, which results in lowering of the electrostatic force effected in the step of the second transfer of the toner image from the image carrying medium to the steel plate. The neutralization or the weakening of the electrostatic charge carried by the toner particles is caused by the discharge occurring in the step of the first transfer of the toner image from the electrostatic recording material to the intermediate image carrying medium. By the discharge, corona ions are generated and neutralize or weaken the charge carried by the toner particles.
SUMMARY OF THE INVENTION
It is, therefore, the primary object of the present invention to provide a print marking apparatus in which the toner image of the marking is easily transferred to the substrate on which the marking is to be finally printed.
Another object of the present invention is to provide a print marking apparatus in which the marking is printed on a substrate with a high resolution.
The above objects of the present invention are accomplished by charging the toner image which is once transferred to the intermediate image carrying medium from the electrostatic image recording member. That is, the toner image is charged again after the step of the first transfer of the toner image so that the toner image will have a sufficient charge in the step of the second transfer thereof. Thus, the toner image is easily transferred from the intermediate image carrying medium to the steel plate and an image of high resolution is obtained on the steel plate.
BRIEF DESCRIPTION OF THE DRAWING
The single FIGURE is a vertical view partly in section of an embodiment of the print marking apparatus in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawing, an image recording drum 10 is used as an electrostatic image recording material for carrying an electrostatic latent image which is developed into a toner image and transferred to an intermediate image carrying medium, i.e. a transfer belt 21 described hereinafter. The image recording drum 10 is a metallic drum, which may be replaced by a metallic belt, carrying a dielectric layer thereon. The image recording drum 10 is uniformly charged in advance by a DC charger 11. Then, the drum 10 is recorded with an electrostatic latent image by means of a set of discharge electrodes 12 which charges the surface of the drum 10 in the opposite polarity to that of the polarity in which the drum 10 is uniformly charged in advance. Since the drum 10 is pre-charged by the DC charger 11 in the opposite polarity to that of the electrostatic latent image, the effective potential of the latent image can be raised by the level of the pre-charge. Thus, the voltage of the discharge electrodes 12 can be lowered. Normally, the drum 10 is pre-charged with a negative voltage and imagewisely charged with a positive voltage by the discharge electrodes 12.
The set of discharge electrodes 12 are arranged in a line parallel to the axis of rotation of the drum 10 at equal intervals and are supplied with a voltage in the form of pulses, whereby an electrostatic latent image is formed on the surface of the drum 10 in a pattern of dots.
The electrostatic latent image thus formed is developed into a toner image by use of toner particles 14 carried by a developing roller 13. The toner particles 14 are retained in a hopper 15 and are fed out of the hopper 15 at a predetermined rate by means of a powder scattering roller 16 located beneath the open bottom of the hopper 15. The toner particles 14 fed out of the hopper 15 fall on the developing roller 13 through a guide duct 17. As the toner particles 14 fall through the guide duct 17, they are charged in negative polarity by means of a pair of charging electrodes 18. The residual toner particles 14 remaining on the surface of the developing roller 13 after the toner particles 14 on the developing roller 13 have been used for developing the electrostatic latent image are scraped off by a fixed brush 19 provided beneath the developing roller 13 in contact therewith and recovered in a container 20.
Under the image recording drum 10 is provided an intermediate image carrying medium in the form of a transfer belt 21. The toner image developed on the drum 10 is contact transferred to the transfer belt 21 and then is further transferred to a steel plate 32 by a gap transfer method. As the intermediate image carrying medium, there may be used a metallic drum or belt carrying a dielectric layer thereon. The transfer belt 21 employed in the embodiment of the invention as shown in the drawing is tensioned around six rollers 22 to 27 in the form of a hexagon. The first roller 22 is a driving roller which is driven by a motor 29 by way of a drive belt 28. Since the drive belt 28 is also tensioned around a pulley 30 of the recording drum 10, the transfer belt 21 and the recording drum 10 are rotated in synchronization with each other. Further, the elements of the drive system are selected so that the peripheral speed of the drum 10 is equal to that of the transfer belt 21. The drum 10 and the belt 21 and other rollers are rotated when a steel plate 32 is fed to the print marking station on feed rollers 31a to 31g. Arrival of the steel plate 32 at the print marking station is detected by a detecting means. Further, the transfer belt 21 is driven at the same speed as that at which the steel plate 32 is fed so that the surface of the transfer belt 21 carrying a toner image to be transferred to the steel plate 32 runs in parallel to and at the same speed as that of the surface of the steel plate 32.
The second roller 23 is a tension roller which is spring biased outwardly by means of a spring 33 to provide the transfer belt 21 with a constant tension. The third and fourth rollers 24 and 25 are movable up and down by means of a drive means (not shown) so that these rollers 24 and 25 move the transfer belt 21 close to the steel plate 32 only when the steel plate 32 passes thereunder and hold the same in an upper position when the steel plate 32 is not present at the print marking station.
The toner particles transferred to the transfer belt 21 are re-charged by a DC charger 34 provided in the vicinity of the path of the transfer belt 21. The space between the DC charger 34 and the surface of the transfer belt 21 is about 10 to 20 mm. The DC charger 34 is charged with a voltage of about 6 to 8 KV. After the toner particles are re-charged by the DC charger 34, they are gap-transferred to the steel plate 32 at the print marking station between the third and fourth rollers 24 and 25. In the course of the gap transfer, a part of the transfer belt 21 is imparted with an ultrasonic vibration from an ultrasonic vibrator 35. At the same time, a high voltage of about 8 to 10 KV is applied across the space between the transfer belt 21 and the steel plate 32 in the transfer station.
The toner particles remaining on the surface of the recording drum 10 after the toner image is transferred to the transfer belt 21 are removed by a rotary bush 36. The rotary brush 36 is provided within a casing 37 connected with a suction means so that the toner particles removed from the surface of the drum 10 by the brush 36 are sucked and covered through the casing 37. The electric charge carried by the recording drum 10 is then neutralized by an AC charger 38.
In operation of the above described embodiment of the present invention, the surface of the recording drum 10 is pre-charged by the DC charger 11 and then is charged imagewise by the set of discharge electrodes 12 in the form of a dotted pattern. Thus, an electrostatic latent image is formed on the surface of the image recording drum 10.
On the other hand, the toner particles 14 fed out of the hopper 15 are charged in negative polarity by the pair of charging electrodes 18 while the toner particles 14 fall through the guide duct 17. The charged toner particles 14 fall on the developing roller 13. As the developing roller 13 rotates, the toner particles 14 thereon are brought into contact with the surface of the image recording drum 10 which carries an electrostatic latent image and are transferred to the surface of the drum 10. The remaining toner particles are removed from the surface of the developing roller 13 by the fixed brush 19 and recovered in a container 20.
The electrostatic latent image is thus developed into a toner image and is then transferred to the transfer belt 21 by contact transfer. A high voltage of about 2 KV is applied across the drum 10 and the belt 21 when the toner image is transferred from the drum 10 to the belt 21. The transfer belt 21 is rotated in synchronization with the steel plate 32 fed to the print marking station on the feed rollers 31a to 31g. As the transfer belt 21 runs along the path around the six rollers 22 to 27, the toner image advances from a transfer station where the toner image is transferred from the drum 10 to the belt 21 to the print marking station where the toner image is transferred from the belt 21 to the steel plate 32. As the toner image advances from the transfer station to the print marking station, the toner image is uniformly re-charged by the DC charger 34. The toner image thus re-charged is transferred from the belt 21 to the steel plate 32 when the toner image passes through the print marking station between the third and fourth rollers 24 and 25. This transfer is a gap transfer conducted with the aid of vibration caused by the ultrasonic vibrator 35 and a high voltage applied across the space between the belt 21 and the steel plate 32. The transfer belt 21 is applied with a voltage at the print marking station of opposite polarity to the voltage applied thereto at the transfer station where the toner image is transferred from the image recording drum 10 to the transfer belt 21. Since the level of the voltage applied at the print marking station is high, the belt 21 is separated from the drum 10 while the toner image is transferred to the steel plate 32.
After the toner image has been transferred from the image recording drum 10 to the belt 21, the surface of the recording drum 10 is cleaned by the rotary brush 36 to remove the residual toner particles remaining on the surface of the recording drum 10. The surface charge carried by the drum 10 is then neutralized by the AC charger 38. Thus, one cycle of the print marking process is finished.
|
In an electrostatic print marking apparatus for printing markings on steel plates wherein an intermediate image carrying medium is used for transferring a toner image from an electrostatic image recording drum to a steel plate, a toner image transferred from the drum to the intermediate image carrying medium is re-charged before it is transferred from the image carrying medium to the steel plate.
| 6
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] Methods and apparatuses consistent with the exemplary embodiments relate to an impedance matching circuit, and more particularly, to a bonding wire impedance matching circuit which matches impedance in a case where bonding wire is connected with another circuit.
[0003] 2. Background Art
[0004] In millimeter bands, since wavelengths are very short, severe transmission loss may occur even by a small mismatched condition. Especially, bonding wire used between various chips such as transceivers etc. cause severe transmission loss. This is transmission loss due to an impedance mismatch caused by an inductance component of bonding wire which is relatively big in proportion to the wavelength of millimeter frequency broadband, which must be compensated by an impedance matching method to prevent performance degradation.
[0005] In a case of an existing millimeter band matching method, most of the designing were made using LC transmission lines. However, embodying such methods require very thin transmission lines of several to dozens of μm, which is difficult to embody in an actual passive environment.
[0006] The conventional matching methods using general LC transmission lines is the most widely used method in impedance compensation circuits regarding bonding wire. However, if the bonding wire becomes longer to hundreds of μm, the impedance (Lp) required in the actual impedance compensation circuit becomes greater, which means that very thin transmission lines of several to dozens of μm must be used. This means makes embodying transmission lines very difficult, considering the line width limitations (50 μm) in an actual LTCC process.
[0007] In order to compensate this problem, researches have been conducted to design impedance of antennas to match the impedance of bonding wire. However, a problem with this method is that it is difficult to apply to cases where the circuits behind chips are transmission lines and not antennas.
[0008] More specifically, researches have been made for methods of compensating chip compensation circuits with input impedance of passive devices such as antennas. This is a method of compensating the inductance of bonding-wire through the input impedance of antennas when designing the antennas, and since it can minimize the matching circuit and thereby minimize the RF system, this method is widely applied to integrations between antennas and chips. However, a problem with this method is that it is difficult to apply to cases where, on circuits behind chips, chips or other transmission lines are arranged instead of antennas.
[0009] As such, conventional impedance matching methods have problems. Accordingly, there is a need to seek a bonding wire impedance matching method applicable to various millimeter bands.
SUMMARY OF THE INVENTION
[0010] The present disclosure has been presented to resolve the aforementioned problems, and the purpose of the present disclosure is to provide an impedance matching circuit which matches impedance using a transformer which is arranged inside a dielectric substrate, and is arranged to overlap with a bonding pad area and an end area of a transmission line.
[0011] According to an exemplary embodiment of the present disclosure, there is provided an impedance matching circuit which includes a dielectric substrate; a ground arranged on a lower surface of the dielectric substrate; a first pad which is arranged on an upper surface of the dielectric substrate, and to which bonding wires is connected; a transmission line which is arranged on an upper surface of the dielectric substrate, and of which an end is arranged by a certain distance from the first pad; and a second pad which is arranged inside the dielectric substrate, and is arranged to overlap with the first pad area and one end area of the transmission line.
[0012] In addition, the second pad may be λ g /4 transformer λ g being a wavelength of a transmission signal).
[0013] Furthermore, a distance between the first pad area and the one end area of the transmission line may be λ g /4, and the area of the second pad overlapping with the first pad area and the one end of the transmission line may be λ g /4 long.
[0014] In addition, the second pad may have a square pad shape of a length of λ g /4.
[0015] Furthermore, the transmission line may be a micro-strip line, and may have a line width of 50 μm or more.
[0016] In addition, the second pad may generate a series capacitance component with the first pad, generate a parallel capacitance component with the ground, and generate a series capacitance component with an end of the transmission line.
[0017] Furthermore, the first pad, second pad, and one end of the transmission line may form an LC resonation circuit.
[0018] In addition, the impedance matching circuit may be produced on a substrate using an LTCC (Low-Temperature Confired Ceramic) method.
[0019] According to various exemplary embodiments of the present disclosure, it becomes possible to provide an impedance matching circuit which matches impedance using a transformer which is arranged inside a dielectric substrate, and is arranged to overlap with a bonding pad area and an end area of a transmission line, thereby enabling transmitting signals at a desired frequency with a minimum insertion loss without using a very thin transmission line which is several to dozens of μm wide or specially designed antennas in order to compensate for inductance. Thus, the present impedance matching circuit may be applied to various millimeter bands.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The above and/or other aspects of the present disclosure will be more apparent by describing certain present disclosure with reference to the accompanying drawings, in which:
[0021] FIG. 1 is a plane view and side view illustrating a structure of an impedance matching circuit, according to an exemplary embodiment of the present disclosure;
[0022] FIGS. 2A and 2B are views illustrating an equivalent circuit of the impedance matching circuit of FIG. 1 , according to an exemplary embodiment of the present disclosure; and
[0023] FIG. 3 is a simulation graph of a transmission loss in a case of applying an impedance matching circuit 100 and in a case of not applying the impedance matching circuit 100 .
DETAILED DESCRIPTION
[0024] Certain exemplary embodiments are described in higher detail below with reference to the accompanying drawings.
[0025] In the following description, like drawing reference numerals are used for the like elements, even in different drawings. The matters defined in the description, such as detailed construction and elements, are provided to assist in a comprehensive understanding of exemplary embodiments. However, exemplary embodiments can be practiced without those specifically defined matters. Also, well-known functions or constructions are not described in detail since they would obscure the application with unnecessary detail.
[0026] FIG. 1 is a plane view and side view illustrating a structure of an impedance matching circuit 100 , according to an exemplary embodiment of the present disclosure. As illustrated in FIG. 1 , the impedance matching circuit 100 includes a first pad 110 , transmission line 120 , second pad 130 , dielectric substrate 140 , and its ground 150 .
[0027] The first pad 110 is arranged on an upper surface of the dielectric substrate 140 , and a bonding wire 110 is connected to the first pad 110 . The bonding wire 115 connects a chip such as an antennae or transceiver etc. with another chip or a transmission line. In addition, the first pad 110 is a bonding pad which is an area connected to the bonding wire 115 .
[0028] The transmission line 120 is arranged on an upper surface of the dielectric substrate 140 , and an end is arranged by a certain distance from the first pad 110 . The transmission line 120 is connected to another circuit or a chip and transmits a signal. One end of the transmission line 120 is distanced by a certain distance from the first pad 110 , and the certain distance is λ g /4.
[0029] Herein, λ g is a wavelength (wavelength where dielectric ratio of the dielectric is reflected) of a signal transmitted in the dielectric substrate 140 . For example, in a case where a transmission signal is 60 GHz, λ g is 1-2 mm. More specifically, the impedance matching circuit 100 is produced on a substrate using an LTCC (Low-Temperature Confired Ceramic) method, and the transmission line 120 is a micro-strip line, and the line width may be 50 μm or more.
[0030] The second pad 130 is arranged inside the dielectric substrate 130 , and is arranged to overlap with the first pad 110 and an end area of the transmission line 120 . The second pad 130 is a conductor, and performs a function of a λ g /4 transformer (λ g being a wavelength of the transmission line).
[0031] Herein, as illustrated in FIG. 1 , the second pad 130 is arranged to be distanced by a certain distance up and low between the first pad 110 and one end area of the transmission line 120 and the dielectric substrate 140 . In addition, the second pad 130 is arranged to be distanced by a certain distance from a ground 150 between the dielectric substrate 140 . By such an arrangement, the second pad 130 performs a λ g /4 transformer function.
[0032] More specifically, the area of the one end of the second pad 130 which overlaps with the first pad 110 area and transmission line 120 may be λ g /4 long, and may have a square pad shape of λ g /4 long. However, the shape of the second pad 130 is not limited thereto, and thus any pad may be used if only it is arranged in such a manner that it overlaps with the first pad 110 area and one end area of the transmission line 120 .
[0033] As such, the second pad 130 generates a series capacitance with the first pad 100 area, generates a series capacitance with the area where it overlaps with the one end of the transmission line, and generates a parallel capacitance with the ground 150 . In such a series capacitance component, the second pad 130 λ g /4 long operates in λ g /4 transformer, and in the first pad 110 , the second pad 130 appears to be a parallel inductance. Through the aforementioned, the first pad 110 , second pad 130 , and one end of the transmission line 120 form an LC resonation circuit.
[0034] The dielectric substrate 140 becomes a basis for a circuit substrate where the impedance circuit 100 is arranged. As illustrated in FIG. 1 , on the upper surface of the dielectric substrate 140 , circuits are arranged, and especially the first pad 110 and transmission line 120 are arranged. In addition, inside (or in a mid layer) the dielectric substrate 140 , the second pad 130 is arranged. Furthermore, on a lower surface of the dielectric substrate 140 , the ground 150 is arranged.
[0035] The impedance matching circuit 100 of such a structure matches the impedance between the bonding wire 1150 connected to the first pad 110 and the transmission line 120 , enabling transceiving signals of desired frequency with a minimum insertion loss, being applicable to various millimeter bands.
[0036] FIGS. 2A and 2B are views illustrating an equivalent circuit of the impedance matching circuit 100 of FIG. 1 .
[0037] As illustrated in FIG. 2A , the impedance matching circuit 100 may be expressed as an equivalent circuit 200 . The equivalent circuit 200 is formed by Cpad 210 which is a series capacitance by the first pad 110 , L bw 215 which is an inductance by the bonding wire 115 , a series capacitance C MS 220 by the transmission line 120 , C square 230 which is a parallel capacitance by the second pad 130 , and λ g /4 transformer 235 by the second pad 130 . In addition, as illustrated in FIG. 2B , C MS 220 and λ g /4 transformer 235 are operated by the parallel inductance of L MS 320 .
[0038] As such, according to the equivalent circuit 200 , the first pad 110 , second pad 130 , and one end of the transmission line 120 form an LC resonation circuit.
[0039] FIG. 3 is a simulation graph of a transmission loss in a case of applying an impedance matching circuit 100 and in a case of not applying the impedance matching circuit 100 . FIG. 3 shows the transmission characteristics in a case of actually embodying the impedance matching circuit 100 according to an exemplary embodiment of the present disclosure. The frequency band has been designed to be 60 GHz, and the bonding wire 115 used is about 500 μm long.
[0040] As illustrated in FIG. 3 , compared to when the impedance matching circuit 100 is not applied, when the impedance matching circuit 100 is applied, the transmission loss by the bonding wire 115 is perfectly corrected in the central frequency 60 GHz.
[0041] Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
|
An impedance matching circuit is provided. The present impedance matching circuit is able to match impedance using a transformer which is arranged inside a dielectric substrate and arranged to overlap with a bonding pad area and an end of a transmission line, thereby enabling transmitting signals at a desired frequency with a minimum insertion loss without using a very thin transmission line which is several to dozens of μm wide or specially designed antennas in order to compensate for inductance. Thus, the present impedance matching circuit may be applied to various millimeter bands.
| 7
|
This invention relates to novel 2-substituted-4-aryl-5-thiazolecarboxylic acids and derivatives thereof as well as their use in compositions and methods for reducing herbicidal injury. More specifically, the invention relates to novel compositions and methods for reducing injury to direct-seeded rice by 2-chloro-2',6'-diethyl-N-(butoxymethyl)acetanilide (hereinafter referred to as butachlor) which comprises treating the rice plant locus or the seed of the rice plant with an effective amount of a 2-substituted-4-aryl-5-thiazolecarboxylic acid or derivative thereof that will be described more fully below.
BACKGROUND OF THE INVENTION
Butachlor is very useful for controlling weeds in the presence of growing crops, especially transplanted rice. Application of butachlor to direct-seeded rice at rates necessary to kill or stunt weeds, however, injures the rice plant, slowing growth and development. Accordingly, butachlor cannot be used for controlling weeds in the presence of direct-seeded rice. Obviously, a safening agent consisting of a chemical compound that could be used to treat either the seed of the rice plant, the rice plant locus, or the rice plant ifself, such that a reduction of injury due to application of the herbicide without a corresponding reduction of herbicidal action on the weed, would be quite beneficial.
DESCRIPTION OF THE INVENTION
In accordance with the novel aspects of the present invention, injury to rice due to application thereto of butachlor may be reduced without a corresponding reduction in injury to the weeds by application to the rice plant locus or the seed of the rice plant prior to planting of an effective amount of a safening agent comprising a 2-substituted-4-aryl-5-thiazolecarboxylic acid or derivative thereof having the formula ##STR1## wherein n is zero or one; X is selected from the group consisting of halogen, lower alkoxy, phenoxy and halophenoxy; Y and Z are independently selected from the group consisting of hydrogen, halogen, trifluoromethyl, nitro and lower alkyl; when n is one, R' is hydrogen, alkyl having up to 6 carbon atoms or agriculturally accepted cations and when n is zero, R' is chloro.
As used herein, the term "lower alkyl" or "lower alkoxy" is understood to include alkyl or alkoxy groups having up to five carbon atoms, inclusive.
The term "alkyl" is understood to include branched, unbranched and cyclic alkyl groups.
"Halogen" includes bromine, chlorine, fluorine and iodine.
"Halophenoxy" is understood to mean phenoxy substituted by one or two halogen moieties.
The term "agriculturally acceptable cations" is understood to mean those cations that are commonly used to form the salt of the free acid. Such cations include, but are not limited to, alkali metal, alkaline earth, substituted amine and ammonium cations.
Safening agents useful in accordance with the present invention include, but are not limited to, ethyl 2-chloro-4-phenyl-5-thiazolecarboxylate; ethyl 2-chloro-4-m-trifluoromethylphenyl-5-thiazolecarboxylate; ethyl 2-chloro-4-p-fluorophenyl-5-thiazolecarboxylate; ethyl 2-chloro-4-p-chlorophenyl-5-thiazolecarboxylate; ethyl 2-chloro-4-o-chlorophenyl-5-thiazolecarboxylate; ethyl 2-chloro-4-m-tolyl-5-thiazolecarboxylate; ethyl 2-chloro-4-p-nitrophenyl-5-thiazolecarboxylate; ethyl 2-ethoxy-4-phenyl-5-thiazolecarboxylate; ethyl 2-ethoxy-4-m-trifluoromethylphenyl-5-thiazolecarboxylate; ethyl 2-(2',4'-dichlorophenoxy)-4-m-trifluoromethylphenyl-5-thiazolecarboxylate; 2-chloro-4-phenyl-5-thiazolecarboxylic acid; 2-chloro-4-m-trifluoromethylphenyl-5-thiazolecarboxylic acid; 2-chloro-4-phenyl-5-thiazolecarbonyl chloride; 2-chloro-4-p-chlorophenyl-5-thiazolecarboxylic acid; 2-chloro-4-p-chlorophenyl-5-thiazolecarbonyl chloride; methyl 2-chloro-4-phenyl-5-thiazolecarboxylate; methyl 2-chloro-4-p-chlorophenyl-5-thiazolecarboxylate; n-propyl 2-chloro-4-phenyl-5-thiazolecarboxylate; isopropyl 2-chloro-4-phenyl-5-thiazolecarboxylate; n-propyl 2-chloro-4-p-chlorophenyl-5-thiazolecarboxylate; sodium salt of 2-chloro-4-phenyl-5-thiazole-carboxylic acid; sodium salt of 2-chloro-4-p-chlorophenyl-5-thiazolecarboxylic acid; isopropylamine salt of 2-chloro-4-phenyl-5-thiazolecarboxylic acid; triethanolamine salt of 2-chloro-4-phenyl-5-thiazolecarboxylic acid.
Preferred are those safening agents of the foregoing formula in which X is halogen, especially chloro. Further preferred are those in which n is one and R' is lower alkyl, especially ethyl.
Generally, the 2-substituted-4-phenyl-5-thiazolecarboxylates of the foregoing formula may be prepared by either of two methods. If the desired compound is one in which X is halogen, especially chloro, the preparation utilized follows the following reaction scheme: ##STR2## In accordance with the above scheme, β-amino-cinnamates prepared in accordance with literature procedures (Lukes et al, Collection Czechoslov, Chem. Commun., Volume 25, Page 607, 1960) was reacted with chlorocarbonylsulfenyl chloride and heated to about 100° C. Crystallization of the resulting mixture with petroleum ether yields the appropriate 4-aryl-2,3-dihydro-2-oxo-5-thiazolecarboxylate which may be converted to the appropriate 4-aryl-2-chloro-5-thiazolecarboxylate by reaction with excess phosphorus oxychloride held at reflux. Excess phosphorus oxychloride is removed under reduced pressure and the residue poured into ice water. Extraction with ether gives the desired product.
In order to more fully illustrate this procedure, the following examples are presented.
EXAMPLE 1
Preparation of Ethyl 2-Chloro-4-Phenyl-5-Thiazolecarboxylate
To a solution of 20.0 g (0.105 mole) of ethyl β-amino-cinnamate in 40 ml. of chlorobenzene under ice cooling was added a solution of 11.6 g (0.112 mole) of chorocarbonylsulfenyl chloride in 10 ml. of chlorobenzene. The reaction mixture was heated at 110° C. for 2 hours, cooled to triturated with petroleum ether. The precipitate was heated with hot benzene, cooled and filtered to give 14.4 g (55%) of ethyl 2,3-dihydro-2-oxo-4-phenyl-5-thiazolecarboxylate as yellow needles. A mixture of 3.0 g (0.012 mole) of ethyl 2,3-dihydro-2-oxo-4-phenyl-5-thiazolecarboxylate and 14 ml. of phosphorus oxychloride was held at reflux for 24 hours and cooled. The reaction mixture was poured into ice water. The solid precipitate was extracted into ether. The ether solution was dried and concentrated under reduced pressure. The residue was recrystallized from hexane to give 2.2 g (68%) of ethyl 2-chloro-4-phenyl-5-thiazolecarboxylate, m.p. 56°-57° C.
Anal. Calc'd. for C 12 H 10 ClNO 2 S: C, 53.83; H, 3.76; N, 5.23; Cl, 13.24; S, 11.98. Found: C, 53.86; H, 3.78; N, 5.21; Cl, 13.14; S, 11.98.
EXAMPLE 2
Preparation of Ethyl 2-Chloro-4-m-Trifluoromethylphenyl-5-thiazolecarboxylate
To a solution of 14.4 g (0.119 mole) of ClCOSCl in 100 ml. of chlorobenzene was added a solution of 28.5 g (0.110 mole) of ethyl β-amino-m-trifluoromethylcinnamate (85% pure) in 20 ml. of chlorobenzene at 20°-25° C. The reaction mixture was stirred at 80° C. for 1 hour, cooled, and triturated with 100 ml. of petroleum ether (30°-75° C.). The precipitate was collected to give 16.7 g of yellow needles, m.p. 167°-170° C., which were recrystallized from benzene to give 13.5 g (39%) of ethyl 2,3-dihydro-2-oxo-4-(m-trifluoromethylphenyl)-5-thiazolecarboxylate as yellow needles, m.p. 168°-171° C. A mixture of 8.0 g (0.0253 mole) of ethyl 2,3-dihydro-2-oxo-4-(m-trifluoromethylphenyl)-5-thiazolecarboxylate, 30 ml. of POCl 3 was heated to reflux for 60 hours. Excess POCl 3 was removed under reduced pressure and the black residue was treated with 100 ml. of water. The aqueous mixture was extracted twice with 100 ml. of ether. The combined ether extracts were dried over MgSO 4 and concentrated under reduced pressure to give 9.6 g of black oil which was chromatographed on 180 g of silica gel. After the earlier fractions were removed, the fractions, eluted with 600 ml. of hexane-ether (4:1 v/v), contained 5.7 g (67%) of oil, which solidified after standing, m.p. 26.5°-27° C.
Anal. Calc'd. for C 13 H 9 ClF 6 NO 2 S: C, 46.50; H, 2.70; N, 4.17; Cl, 10.56. Found: C, 46.61; H, 2.71; N, 4.19; Cl, 10.70.
An alternate procedure for preparing the 2-halo-4-aryl-5-thiazolecarboxylates of the invention encompasses the reaction of a substituted benzoylacetate with sulfuryl chloride to prepare 2-chloro-benzoylacetate which may be converted to 2-amino-4-aryl-5-thiazolecarboxylates by reaction with thiourea in ethanol at reflux. Ethanol is then removed under reduced pressure and the residue neutralized with sodium bicarbonate solution to give a 2-amino-4-aryl-5-thiazolecarboxylic acid ester. A solution of said ester in appropriate acid is diazotized at -5° to 30° C. with sodium nitrite. The resulting diazonium salt solution is poured into the corresponding cuprous halide or potassium iodide solution. After gas evolution had subsided, the reaction mixture is extracted with ether. The ether extract is dried and concentrated and the residue is purified by either Kugelrohr distillation at reduced pressure or by chromatography.
For purposes of clarification, the following reaction scheme and examples are provided. ##STR3##
EXAMPLE 3
Preparation of Ethyl 2-Chloro-4-(p-Fluorophenyl)-5-Thiazolecarboxylate
A mixture of 10.5 g (0.05 mole) of ethyl p-fluorobenzoylacetate, 6.7 g (0.05 mole) of sulfuryl chloride and 30 ml. of chloroform was held at reflux for 18 hours and cooled. The chloroform solution was washed with water, dried (MgSO 4 ) and concentrated under reduced pressure. The residue was distilled to give 10.8 g (88%) of ethyl 2-chloro-(p-fluoro)-benzoylacetate as an oil. A mixture of 10.8 g (0.0441 mole) of ethyl 2-chloro-(p-fluoro)benzoylacetate, 3.36 g (0.0441 mole) of thiourea, 20 ml. of water and 10 ml. of ethanol was held at reflux for 3 hours. Ethanol was removed under reduced pressure. The residue was made basic with saturated sodium bicarbonate. The solid was filtered, washed with water and recrystallized from ethanol to give 8.9 g (76%) of ethyl 2-amino-4-(p-fluorophenyl)-5-thiazolecarboxylate as white prisms, m.p. 205°-208° C. To 4.0 g (0.015 mole) of ethyl 2-amino-4-(p-fluorophenyl)-5-thiazolecarboxylate was added 30 ml. of concentrated hydrochloric acid and 30 ml. of glacial acetic acid. The carboxylate did not dissolve completely. To this mixture was added 30 ml. of chloroform. The carboxylate dissolved gradually into the chloroform solution. the reaction mixture was cooled to 0°-5° C. with an ice bath. To the above mixture was added with vigorous stirring 4.0 g (0.058 mole) of sodium nitrite. The reaction mixture was stirred at 5°-10° C. for 30 minutes and poured into a solution of 1.48 g (0.0150 mole) of cuprous chloride in 20 ml. of concentrated hydrochloric acid. After the gas evolution subsided, the reaction mixture was diluted with water. The chloroform layer was separated and the aqueous layer was extracted with chloroform. The combined chloroform solution was washed with water followed by saturated sodium bicarbonate, dried (MgSO 4 ) and concentrated under reduced pressure. The residual solid was recrystallized from ethanol to give 3.3 g (77%) of ethyl 2-chloro-4-(p-fluorophenyl)-5-thiazolecarboxylate as orange needles, m.p. 113°-114° C.
Anal. Calc'd. for C 12 H 9 ClFNO 2 S: C, 50.44; H, 3.17; N, 4.90. Found: C, 50.42; H, 3.18; N, 4.90.
EXAMPLE 4
Preparation of Ethyl 2-Chloro-4-p-Chlorophenyl-5-Thiazolecarboxylate
To a cold (5° C.) vigorously stirred mixture of 121.87 g (0.936 mole) of ethyl acetoacetate, 314 ml. of benzene and 626 ml. of water was added 41.25 ml. of 33% sodium hydroxide. To the above mixture was added simultaneously in two dropping funnels 177.0 g (1.01 mole) of p-chlorobenzoyl chloride and 188.8 ml. of 33% sodium hydroxide in 2 hours. The reaction mixture became pasty. The reaction mixture was heated at 35° C. for 1 hour, cooled and filtered to give 170.0 g of sodium salt of ethyl 2-benzoylacetoacetate. Part (150 g) of this salt was added to a mixture of 39.0 g (0.729 mole) of ammonium chloride and 78 ml. of concentrated ammonium hydroxide in 780 ml. of water. The mixture was stirred at 40°-50° C. for 3 hours and cooled in an ice bath. The precipitate was filtered to give 115.5 g of yellow solid which was Kugelrohr distilled to give 76.0 g (38% based on ethyl acetoacetate) of crude ethyl p-chlorobenzoylacetate. A mixture of 40.0 g (0.175 mole) of crude ethyl p-chlorobenzoylacetate, 24.2 g (0.18 mole) of sulfuryl chloride and some chloroform was held at reflux for 6 hours, cooled and concentrated to give 49.0 g of crude ethyl 2-chloro-p-chlorobenzoylacetate. A mixture of 46.0 g (0.174 mole) of crude ethyl 2-chloro-p-chlorobenzoylacetate, 13.25 g (0.174 mole) of thiourea, and 174 ml. of ethanol was held at reflux for 2 hours and cooled. The precipitate was filtered and neutralized with saturated sodium bicarbonate. The insoluble material was filtered to give 37.0 g (80%) of ethyl 2-amino-4-p-chlorophenyl-5-thiazolecarboxylate, m.p. 198°-200° C. To a cold (-5° C.) mixture of 11.3 g (0.04 mole) of ethyl 2-amino-4-p-chlorophenyl-5-thiazolecarboxylate and 80 ml. of 85% phosphonic acid was added 40 ml. of 70% nitric acid. To the above mixture was added with vigorous stirring, 4.0 g (0.0434 mole) of sodium nitrite in 20 minutes at -5°-0° C. The reaction mixture was stirred at -5°-0° C. for 10 minutes and poured into a mixture of 4.0 g (0.04 mole) of cuprous chloride, 20 ml. of concentrated hydrochloric acid and 20 ml. of water. The reaction mixture was stirred at room temperature for 30 minutes, after which time evolution had subsided. The precipitate was filtered to give 10.5 g of solid which was Kugelrohr distilled (145° C. at 0.05 mm Hg) to give 6.0 g of solid, m.p. 113°-120° C., which was recrystallized from hot ethanol to give 4.4 g (37%) of ethyl 2-chloro-4-p-chlorophenyl-5-thiazolecarboxylate as a white solid, m.p. 119°-120° C.
Anal. Calc'd. for C 12 H 9 Cl 2 NO 2 S: C, 47.70; H, 3.00; N, 4.64. Found: C, 47.71; H, 2.97; N, 4.55.
EXAMPLE 5
Preparation of Ethyl 2-Chloro-4-(o-Chlorophenyl)-5-Thiazolecarboxylate
To a cold (5° C.) mixture at 55.0 g (0.423 mole) of ethyl acetoacetate, 70 ml. of benzene, 18.3 ml. of 33% sodium hydroxide, and 141 ml. of water was added simultaneously with vigorous stirring 80.0 g (0.457 mole) of o-chlorobenzoyl chloride and 76 ml. of 33% sodium hydroxide in 1 hour as described in Example 4. The aqueous solution of sodium salt of ethyl o-chlorobenzoylacetoacetate was stirred with 22.5 g (0.424 mole) of ammonium chloride for 18 hours. The aqueous solution was then saturated with 25.0 g of sodium chloride. At this moment, some precipitate formed which was filtered. The analysis indicated this material was mainly the sodium salt of ethyl o-chlorobenzoylacetoacetate. The sodium salt and the aqueous filtrate were combined and acidified with dilute hydrochloric acid. The oil which separated was extracted with ether. The ether solution was dried (MgSO 4 ) and concentrated under reduced pressure. The residue was Kugelrohr distilled to give 30.0 g of oil which contained mainly ethyl o-chlorobenzoylacetoacetate. This material was stirred with a mixture of 7.2 g of ammonium chloride, 14 ml. of concentrated ammonium hydroxide and 150 ml. of water and worked up as described in Example 4 to give 16.6 g (15%) of crude ethyl o-chlorobenzoylacetate which was about 92% pure. A mixture of 15.0 g (0.065 mole) of ehtyl o-chlorobenzoylacetate, 9.5 g (0.070 mole) of sulfuryl chloride and 20 ml. of chloroform was held at reflux for 6 hours and concentrated to give 17.3 g of crude ethyl 2-chloro-o-chlorobenzoylacetate. A mixture of 17.0 g (0.065 mole) of ethyl 2-chloro-o-chlorobenzoylacetate, 4.94 g (0.065 mole) of thiourea and 65 ml. of ethanol was held at reflux for 2 hours and worked up as described in Example 4 to give 15.0 g of solid, m.p. 114°-136° C. which was recrystallized twice from ethanol to give 5.8 g (31%) of ethyl 2-amino-4-(o-chlorophenyl)-5-thiazolecarboxylate, m.p. 162°-164° C. Part (1.0 g) of this material was recrystallized from toluene to give 0.75 g of pure ethyl 2-amino-4-(o-chlorophenyl)-5-thiazolecarboxylate, m.p. 165°-166° C. A solution of 4.2 g (0.015 mole) of ethyl 2-amino-4-(o-chlorophenyl)-5-thiazolecarboxylate in 50 ml. of 85% phosphoric acid and 15 ml. of nitric acid was diazotized with 1.12 g (0.016 mole) of sodium nitrite as described in Example 4. The diazonium salt solution was poured into a solution of 1.50 g (0.015 mol) of cuprous chloride in 7.5 ml. of concentrated hydrochloric acid and 7.5 ml. of water. The reaction mixture was worked up as described in Example 4 to give 4.0 g of oil which was Kugelrohr distilled (150° C. at 0.3 mm) to give 2.0 g of oil. The material was purified to give 0.66 g (15%) of ethyl 2-chloro-4-(o-chlorophenyl)-5-thiazolecarboxylate as a colorless liquid.
Anal. Calc'd. for C 12 H 9 Cl 2 NO 2 S: C, 47.69; H, 3.00; N, 4.63; Cl, 23.43. Found: C, 47.61; H, 3.02; N, 4.62; Cl, 23.45.
EXAMPLE 6
Preparation of Ethyl 2-Chloro-4-(m-Tolyl)-5-Thiazolecarboxylate
To a cold (5° C.) mixture of 137.5 g (1.05 mole) of ethyl acetoacetate, 175 ml. of benzene, 325 ml. of water, and 45.8 ml. of 33% sodium hydroxide was added simultaneously 221.05 g (1.430 mole) of m-toluoyl chloride and 190 ml. of 33% sodium hydroxide as described in Example 4. The aqueous solution of sodium salt of ethyl m-toluoylacetoacetate was stirred with 56.3 g of ammonium chloride overnight and worked up as described in Example 4 to give 38.0 g (17%) of crude ethyl m-toluoylacetate after a Kugelrohr distillation (95°-98° C. at 0.05 mm Hg). A mixture of 20.6 g (0.1 mole) of crude ethyl m-toluoylacetate, 13.6 g (0.105 mole) of sulfuryl chloride, and 30 ml. of chloroform was held at reflux for 6 hours and worked up as described in Example 4 to give 25.0 g of ethyl 2-chloro-m-toluoylacetate, which was used directly as described below. A mixture of 22.5 g (0.1 mole) of ethyl 2-chloro-m-toluoylacetate, 7.6 g (0.1 mole) of thiourea and 100 ml. of ethanal was held at reflux for 2 hours and worked up as described in Example 4 to give 23.0 g of solid, which was recrystallized from ethanol to give 11.6 g (44%) of ethyl 2-amino-4-(m-tolyl)-5-thiazolecarboxylate, m.p. 185°-187° C. An additional 4.5 g (17%) of less pure ethyl 2-amino-4-(m-tolyl)-5-thiazolecarboxylate, m.p. 183°-184° C. was obtained by concentration of the mother liquor. To a cold (-5° C.) mixture of 10.5 g (0.04 mole) of ethyl 2-amino-4-(m-tolyl)-5-thiazolecarb and 80 ml. of 85% phosphoric acid was added 40 ml. of 70% nitric acid. To the vigorously stirred above mixture was added 3.0 g (0.0434 mole) of sodium nitrite in 20 minutes. The reaction mixture was stirred for 10 minutes and poured into a mixture of 4.0 g (0.04 mole) of cuprous chloride, 20 ml. of concentrated hydrochloric acid and 20 ml. of water. After the gas evolution had subsided the reaction mixture was extracted with ether, dried (MgSO 4 ) and concentrated under reduced pressure to give 10 g of oil which was Kugelrohr distilled (135°-140° C. at 0.05 mm) to give 6.5 g of oil, which was crystallized from ethanol to give 3.9 g (34%) of the desired product as a white solid, m.p. 41°-42° C.
Anal. Calc'd. for C 13 H 12 ClNO 2 S: C, 55.42; H, 4.29; N, 4.97; Cl, 12.58. Found: C, 55.38; H, 4.33; N, 4.99; Cl, 12.53.
EXAMPLE 7
Preparation of Ethyl 2-Chloro-4-(p-Nitrophenyl)-5Thiazolecarboxylate
Ethyl 2-chloro-p-nitrobenzoylacetate, obtained from ethyl p-nitrobenzoylacetate and sulfuryl chloride in accordance with the procedure of Balog et al, Studio. Univ. Bebes. Boylai., Vol. 1, No. 2, Page 155 (1960), was converted to ethyl 2-amino-4-p-nitrophenyl-5-thiazolecarboxylate with thiourea in accordance with a procedure in the above-mentioned publication. To a cooled (15° C.) solution of 10.0 g (0.0334 mole) of ethyl 2-amino-4-(p-nitrophenyl)-5-thiazolecarboxylate in 100 ml. of concentrated HCl and 100 ml. of glacial HOAc was added 7.0 g (0.101 mole) of NaNO 2 in 15 minutes. The reaction mixture was stirred for 10 minutes and poured into a solution of 3.78 g (0.038 mole) of CuCl in 60 ml. of concentrated HCl. A slow gas evolution occurred which was accelerated when 50 ml. of water was added to the reaction mixture. The reaction mixture gradually turned yellow with precipitation of white solid. The precipitate was extracted with CHCl 3 . The CHCl 3 solution was dried (MgSO 4 ) and concentrated under reduced pressure. The residue was boiled with hot MeOH and filtered. The solid was recrystallized from acetone-chloroform to give 2.4 g of the desired product, m.p. 146°-148° C.
Anal. Calc'd. for C 12 H 9 ClN 2 O 4 S: C, 46.09; H, 2.90; N, 8.95; Cl, 11.34. Found: C, 46.08; H, 2.92; N, 8.95; Cl, 11.23.
The analogues in which X is lower alkoxy, phenoxy or halophenoxy are prepared by treating the corresponding 2-chloro compound with sodium alkoxide or potassium phenoxide. Sodium alkoxide, such as sodium ethoxide, may be prepared from sodium and dried ethanol. The reaction mixture containing sodium alkoxide and the appropriate 2-chloro compound is stirred for a long period of time and poured into dilute hydrochloric acid. The organic layer is extracted with ether. The ether solution is dried, and concentrated and the residue is Kugelrohr distilled at reduced pressure (2 mm) to give ethyl 2-ethoxy-4-phenyl-5-thiazolecarboxylate or ethyl 2-ethoxy-4-(m-trifluoromethylphenyl)-5-thiazolecarboxylate.
EXAMPLE 8
Preparation of Ethyl 2-Ethoxy-4-Phenyl-5-Thiazolecarboxylate
To a solution of NaOC 2 H 5 , prepared from 1.8 g (0.0783 g atom) of Na and 25 ml. of dry ethanol (dried from Mg (OEt) 2 ) was added 4.0 g (0.0149 mole) of Example 1. The reaction mixture was stirred at room temperature under N 2 for 20 hours and poured into 50 ml. of ice cold 6 NHCl. The mixture was extracted twice with 50 ml. of ether. The ether extracts were dried (MgSO 4 ) and concentrated under reduced pressure. The residue was distilled on a Kugelrohr at 2 mm (140°-170° C.) to give 3.55 g (86%) of the desired product as white solid, m.p. 32°-34° C.
Anal. Calc'd. for C 14 H 15 NO 3 S: C, 60.63; H, 5.45; N, 5.05. Found: C, 60.62; H, 5.46; N, 5.06.
EXAMPLE 9
Preparation of Ethyl 2-Ethoxy-4-(m-Trifluoromethylphenyl)-5-Thiazolecarboxylate
To a NaOC 2 H 5 solution, preparation from 0.5 g (0.217 g atom) of Na and 25 ml. of dry ethanol was added 1.0 g (0.00298 mole) of Example 2. The solution was stirred at room temperature for 16 hours and poured into 50 ml. of 6 N HCl. The mixture was extracted twice with 50 ml. of ether. The combined ether solution was washed with saturated NaHCO 3 , dried (MgSO 4 ) and concentrated under reduced pressure. The residue was chromatographed on 20 g of silica gel using ether-petroleum ether (1:5 v/v) as eluant. The first 300 ml. eluant was concentrated under reduced pressure and the residue was distilled on a Kugelrohr at 2 mm (temperature 140°-170° C.) to give 0.65 g (63%) of the desired product as white solid, m.p. 69°-72° C.
Anal. Calc'd. for C 15 H 14 F 3 NO 3 S: C, 52.17; H, 4.09; N, 4.06. Found: C, 52.12; H, 4.08; N, 4.09.
EXAMPLE 10
Preparation of Ethyl 2-(2',4'-Dichlorophenoxy)-4-(m-Trifluoromethylphenyl)-5-Thiazolecarboxylate
A mixture of 3.68 g (0.0110 mole) of ethyl 2-chloro-4-m-trifluoromethylphenyl-5-thiazolecarboxylate, 1.96 g (0.0120 mole) of 2,4-dichlorophenyl, 1.66 g (0.012 mole) of K 2 CO 3 and 50 ml. of acetone was held at reflux for 22 hours. Acetone was removed under reduced pressure. The residue was treated with 50 ml. of water and extracted with 100 ml. of ether. The ether solution was washed successively with 50 ml. of NaHCO 3 , 30 ml. of 10% NaOH and 50 ml. of water, dried (MgSO 4 ) and concentrated under reduced pressure. The residue was recrystallized twice from hexane to give 4.1 g (81%) of the desired product as white needles, m.p. 72°-73° C.
Anal. Calc'd. for C 19 H 12 F 3 Cl 2 NO 2 S: C, 49.36; H, 2.62; N, 3.03; Cl, 15.34. Found: C, 49.32; H, 2.62. N, 3.04; Cl, 15.40.
Various esters may be prepared by reaction of the corresponding acid chloride and the appropriate alcohol. The acid chloride is prepared by reaction of the free acid with thionyl chloride.
Salts may be prepared by reaction of the free acid with the appropriate base.
EXAMPLE 11
Preparation of 2-Chloro-4-Phenyl-5-Thiazolecarboxylic Acid
A mixture of 53.4 g (0.2 mole) of ethyl 2-chloro-4-phenyl-5-thiazolecarboxylate, 8.0 g (0.2 mole) of NaOH, 200 ml. of water and 400 ml. of tetrahydrofuran was stirred for 16 hours and extracted with ether. The organic layer was discarded. The aqueous layer was made acidic and the precipitate was collected and air-dried to give 43.2 g (90%) of the desired product, m.p. 170°-171° C.
Anal. Calc'd. for C 10 H 6 ClNO 2 S: C, 50.11; H, 2.52; N, 5.84. Found: C, 50.06; H, 2.55; N, 5.84.
EXAMPLE 12
Preparation of 2-Chloro-4-Phenyl-5-Thiazolecarbonyl Chloride
A mixture of 40.6 g (0.17 mole) of 2-chloro-4-phenyl-5-thiazolecarboxylic acid and 100 ml. of thionyl chloride was heated on a steam bath for 6 hours and concentrated under reduced pressure to give 38.0 g (88%) of the acid chloride as a white solid, m.p. 53°-55° C.
Anal. Calc'd. for C 10 H 5 Cl 2 NOS: C, 46.53; H, 1.95; N, 5.43. Found: C, 46.45; H, 1.99; N, 5.41.
EXAMPLE 13
Preparation of Methyl 2-Chloro-4-Phenyl-5-Thiazolecarboxylate
A mixture of 5.16 g (0.02 mole) of the compound of Example 12 and 40 ml. of methanol was held at reflux for 1 hour and concentrated under reduced pressure. The residual solid was stirred with ether. The ether solution was washed with saturated sodium bicarbonate, dried (MgSO 4 ), and concentrated under reduced pressure to give 3.1 g (61%) of the desired product as a white solid, m.p. 55°-57° C.
Anal. Calc'd. for C 11 H 8 ClNO 2 S: C, 52.07; H, 3.17; N, 5.52. Found: C, 52.02; H, 3.21; N, 5.50.
EXAMPLE 14
Preparation of n-Propyl 2-Chloro-4-Phenyl-5-Thiazolecarboxylate
A mixture of 5.16 g (0.02 mole) of the compound of Example 12 and 40 ml. of n-propanol was held at reflux for 7 hours and concentrated under reduced pressure. The residual waxy material (6.09 g) was stirred with ether and filtered to give 1.0 g of solid, m.p. 155°-156° C. The ether solution was washed with saturated sodium bicarbonate, dried (MgSO 4 ), and concentrated under reduced pressure to give 3.5 g of waxy material which was heated with hexane and filtered. The hexane filtrate was concentrated under reduced pressure to give 2.1 g of oil which was dissolved in ether. The ether solution was washed with 10% sodium hydroxide solution, dried (MgSO 4 ) and concentrated under reduced pressure to give 1.8 g of oil which was Kugelrohr distilled to give 1.4 g (25%) of the desired product as a colorless oil; n D 25 =1.5868.
Anal. Calc'd. for C 13 H 12 ClNO 2 S: C, 55.41; H, 4.29; N, 4.97. Found: C, 55.35; H, 4.30; N, 4.95.
In accordance with the novel aspects of the present invention, the 2-substituted-4-aryl-5-thiazolecarboxylic acids and derivatives thereof are useful for reducing herbicidal injury to rice plants. The amount of safening agent employed in the method and compositions of the invention will vary depending upon the manner of application, rate of application, environmental factors as well as other factors known in the art. In each instance, the amount employed is a safening effective amount, i.e., the amount which reduces crop injury by the herbicide.
The safening agent may be applied to the plant locus in a mixture with the herbicide or it may be applied directly to the rice seed itself. By application to the "plant locus" is meant application to the plant growing medium, such as the soil, as well as the seeds, emerging seedlings, roots, stems, leaves, flowers, fruits or other plant parts.
To illustrate the effectiveness of the 2-substituted-4-aryl-5-thiazolecarboxylic acids and derivatives thereof, the following examples are presented. These examples are presented merely as being illustrative of the novel aspects of the invention and are not intended to be a limitation as to the scope thereof.
EXAMPLE 15
A good grade of top soil is placed in a container and compacted to a depth of approximately 1.27 cm. from the top of said container. A predetermined number of rice seeds to be tested are placed on top of the soil. A quantity of soil sufficient to substantially fill the container is measured and placed in a second container. A measured quantity of the safening agent dispersed or dissolved in a suitable carrier is applied to the soil in the second container. A measured quantity of butachlor dispersed or dissolved in a suitable carrier is then sprayed on the soil already treated with the safening agent. The soil containing the safening agent and herbicide is thoroughly mixed. This mixing is sometimes referred to as incorporation of the herbicide and safening agent into the soil. The mixing or incorporation provides a substantially uniform distribution of the safening agent and herbicide throughout the soil. The seeds are covered with the soil containing the safening agent and herbicide and the pans are leveled. The pans are then placed on a sand bench in the greenhouse and watered from below as needed. The plants are observed at the end of approximately 21 days and the results in terms of percent inhibition of each seed lot are recorded. For each test series a pan of plants is also prepared containing no herbicide and no safening agent as a control. Additionally, for each test, a pan of plants is prepared with soil covering the seed containing no herbicide and only the measured amount of safening agent being incorporated into the soil covering the seeds to ascertain any herbicidal effect of the safening agent alone. For each series of tests the herbicidal effect of the herbicide is observed from pans of plants treated with the same quantity of herbicide alone. The "safening effect" is determined by adding the hericidal effect of the herbicide when applied alone to the herbicidal effect of the safening agent when applied alone (in no instance, however, will this sum be greater than 100) and substracting from that the herbicidal effect obtained when the herbicide and safening agent are incorporated into the soil as discussed above.
Table I summarizes the results obtained when the compounds of the invention were tested in accordance with the procedure of Example 15.
TABLE I______________________________________ Safening Agent Rate of Rate of(Compound of Safening Herbicide SafeningExample Number) Agent (kg/h) (kg/h) Effect______________________________________1 8.96 4.48 758 8.96 4.48 759 8.96 4.48 202 8.96 4.48 5011 8.96 4.48 5012 8.96 4.48 5013 8.96 4.48 3014 8.96 4.48 207 8.96 4.48 253 8.96 6.72 654 8.96 6.72 856 8.96 6.72 655 8.96 6.72 6510 8.96 4.48 43______________________________________
EXAMPLE 16
A good grade of top soil is placed in a plastic pot. A measured quantity of the safening agent dispersed or dissolved in a suitable carrier is sprayed on the soil surface. A measured quantity of butachlor herbicide dissolved in a solvent is sprayed on the soil surface. Presoaked rice is seeded into the pots that were previously flooded with water and the water level lowered below the soil surface for one week. The pots are flooded at least up to the soil surface for the duration of the test. The plants are observed at the end of approximately 21 days and the results in terms of the percent inhibition of rice is recorded. As in Example 15, for each test pots are prepared containing soil treated only with butachlor. For each test, pots are also prepared containing soil treated only with the safening agent. Pots are also prepared in which the soil is not treated with either the herbicide or the safening agent. The safening effect is determined in accordance with Example 15.
Table II summarizes the results obtained when the compounds of the invention were tested in accordance with the procedure of Example 16.
TABLE II______________________________________ Safening Agent Rate of Rate of(Compound of Safening Herbicide SafeningExample Number) Agent (kg/h) (kg/h) Effect**______________________________________1 1.12 0.14 78 1.12 0.56 992 0.56 0.07 68 0.56 0.28 26 0.56 1.12 *11 0.56 0.07 * 0.56 0.28 63 0.56 1.12 4512 0.56 0.07 35 0.56 0.28 80 0.56 1.12 6210 0.56 0.07 * 0.56 0.28 * 0.56 1.12 *7 0.56 0.07 * 0.56 0.28 38 0.56 1.12 *3 0.56 0.07 30 0.56 0.28 73 0.56 1.12 624 0.56 0.07 30 0.56 0.28 70 0.56 1.12 32______________________________________ *Safening effect between 0 and 20 **Mean of two replicates
EXAMPLE 17
5.08 cm. of a good grade of top soil is placed in a 7.62 cm. deep plastic pot. A predetermined number of barnyard grass seeds are applied to the soil surface. A measured quantity of the safening agent dispersed or dissolved in a suitable carrier is sprayed on the soil surface. A measured quantity of butachlor herbicide dissolved in a solvent is sprayed on the soil surface. Pre-soaked rice is seeded into the pots that were previously flooded with water. The water level is lowered below the soil surface for one week to allow barnyard grass to emerge. The pots are flooded just above the soil surface for the duration of the test. The plants are observed at the end of approximately 21 days and the results in terms of percent inhibition recorded. For each test, pots are prepared containing soil treated only with butachlor. For each test, pots are prepared containing soil treated only with the safening agent. Pots are also prepared containing untreated soil. Table II represents the results of tests conducted in accordance with the procedure of Example 17.
TABLE III______________________________________ Safening Agent Rate of Rate of Inhibition*(Compound of Safening Herbicide BarnyardExample Number) Agent (kg/h) (kg/h) Rice Grass______________________________________-- -- 0.07 31 99-- -- 0.28 74 100-- -- 1.12 98 1003 0.07 -- 0 03 0.07 0.07 0 973 0.07 0.28 5 993 0.07 1.12 70 1003 0.28 -- 0 03 0.28 0.07 0 923 0.28 0.28 5 1003 0.28 1.12 58 1003 1.12 -- 0 03 1.12 0.07 0 923 1.12 0.28 0 1003 1.12 1.12 43 1004 0.07 -- 0 04 0.07 0.07 0 994 0.07 0.28 0 1004 0.07 1.12 78 1004 0.28 -- 0 04 0.28 0.07 0 994 0.28 0.28 0 994 0.28 1.12 40 1004 1.12 -- 0 04 1.12 0.07 0 994 1.12 0.28 0 994 1.12 1.12 28 100______________________________________ *Mean of two replicates
EXAMPLE 18
5.08 cm. of a good grade of top soil is placed in a 7.62 cm. deep plastic pot. A predetermined number of barnyard grass seeds are applied to the soil surface. A measured quantity of the safening agent and butachlor dispersed or dissolved in a suitable carrier is applied to the soil surface. Pre-soaked rice is seeded into the pots that were previously flooded with water. The water level is lowered below the soil surface for one week. The pots are flooded just above the soil surface for the duration of the test. The plants are observed at the end of approximately 21 days and the results in terms of percent inhibition recorded. For each test, pots are prepared containing soil treated only with butachlor. For each test, pots are prepared containing soil treated only with the safening agent. Pots are also prepared with untreated soil. Table IV represents the results of tests conducted in accordance with the procedure of Example 18.
TABLE IV______________________________________Safening Agent Rate of Rate of % Inhibition*(Compound of Safening Herbicide BarnyardExample Number) Agent (kg/h) (kg/h) Rice Grass______________________________________-- -- 0.07 64 100-- -- 0.28 78 100-- -- 1.12 100 1008 1.12 -- 0 08 1.12 0.07 30 1008 1.12 0.28 88 1008 1.12 1.12 95 100Ethyl 2-(2',4'- 1.12 -- 0 0dichlorophenoxy)- 1.12 0.07 15 834-phenyl-5-thia-zolecarboxylate 1.12 0.28 88 98Ethyl 2-(2',4'-dichlorophenoxy)- 1.12 1.12 99 1004-phenyl-5-thia-zolecarboxylateTriethanolamine 1.12 -- 0 0salt of 2-chloro-4-phenyl-5-thia- 1.12 0.07 0 88zolecarboxylate 1.12 0.28 20 99 1.12 1.12 60 1004 0.07 -- 0 04 0.07 0.07 5 904 0.07 0.28 63 1004 0.07 1.12 88 1004 0.28 -- 0 04 0.28 0.07 0 854 0.28 0.28 30 1004 0.28 1.12 40 1004 1.12 -- 0 04 1.12 0.07 0 854 1.12 0.28 30 1004 1.12 1.12 88 100______________________________________ *Mean of two replicates
EXAMPLE 19
5.08 cm. of a good grade of top soil is placed in a 7.62 cm. deep plastic pot. A predetermined number of weed seeds and rice seeds are applied to the soil surface. Butachlor and ethyl 2-chloro-4-phenyl-5-thiazolecarboxylate are applied to a soil cover layer as a mixture and incorporated by shaking the treated soil cover layer in a plastic bag. The cover layers were then placed on the pre-seeded pots. The plants are observed at the end of approximately 21 days and the results in terms of percent inhibition recorded. For each test, pots are prepared containing soil treated only with butachlor. For each test, pots are prepared containing soil treated only with the safening agent. Pots are also prepared with untreated soil. Table V represents the results of tests conducted in accordance with the procedure of Example 19.
TABLE V______________________________________Rate of Percent InhibitionHerbi- Rate of Barn-cide Safening yard Crab- Fox(kg/h) Agent (kg/h) Grass grass Panicum tail Rice______________________________________2.24 -- 100 100 99 100 504.48 -- 100 100 100 100 788.96 -- 100 100 100 100 93-- 8.96 0 0 0 0 02.24 8.96 100 100 100 100 84.48 8.96 100 100 100 100 438.96 8.96 100 100 100 100 45______________________________________
The above examples illustrate that the thiazolecarboxylates of the present invention are useful in reducing herbicidal injury to rice plants. The safening agents may be applied to the plant locus as a mixture, i.e., a mixture of a herbicidally effective amount of butachlor and a safening effective amount of safening agent, or sequentially, i.e., the plant locus may be treated with an effective amount of butachlor followed by a treatment with the safening agent or vice versa. The ratio of butachlor to safening agent may vary depending upon various factors, such as the weeds to be inhibited, mode of application, etc., but normally a herbicide to safening agent ratio ranging from 1:25 to 25:1 (preferably 1:5 to 5:1) parts by weight may be employed.
The herbicide, safening agent or mixture thereof may be applied to the plant locus alone or the herbicide, safening agent or mixture thereof may be applied in conjunction with a material referred to in the art as an adjuvant in liquid or solid form. Mixtures containing the appropriate herbicide and safening agent usually are prepared by admixing said herbicide and safening agent with an adjuvant including diluents, extenders, carriers and conditioning agents to provide compositions in the form of finely-divided particulate solids, granules, pellets, wettable powders, dusts, solutions and aqueous dispersions or emulsions. Thus, the mixture may include an adjuvant such as a finely-divided particulate solid, a solvent liquid of organic origin, water, a wetting agent, dispersing agent, or emulsifying agent or any suitable combination of these.
When applying the herbicide, safening agent or mixtures thereof to the plant locus, useful finely-divided solid carriers and extenders include, for example, the talcs, clays, pumice, silica, diatomaceous earth, quartz, Fullers earth, sulfur, powdered cork, powdered wood, walnut flour, chalk, tobacco dust, charcoal and the like. Typical liquid diluents useful include for example, Stoddard solvent, acetone, alcohols, glycols, ethyl acetate, benzene and the like. Such compositions, particularly liquids and wettable powders, usually contain as a conditioning agent one or more surface-active agents in amounts sufficient to render a given composition readily dispersible in water or in oil. By the term "surface-active agent", it is understood that wetting agents, dispersing agents, suspending agents and emulsifying agents are included therein. Such surface-active agents are well known and reference is made to U.S. Pat. No. 2,547,724, Columns 3 and 4, for detailed examples of the same.
Compositions of this invention generally contain from about 5 to 95 parts herbicide and safening agent, about 1 to 50 parts surface-active agent and about 4 to 94 parts solvent, all parts being by weight based on the total weight of the composition.
The application of the herbicide, safening agent or mixtures thereof in a liquid or particulate soli form can be carried out by conventional techniques utilizing, for example, spreaders, power dusters, boom and hand sprayers, spray dusters and granular applicators. The compositions can also be applied from airplanes as a dust or spray. If desired, application of the compositions of the invention to plants can be accomplished by incorporating the compositions in the soil or other media.
Although this invention has been described with respect to specific modifications, the details thereof are not to be construed as limitations, for it will be apparent that various equivalents, changes and modifications may be resorted to without departing from the spirit and scope thereof and it is understood that such equivalent embodiments are intended to be included herein.
|
These compounds have been found to be effective in reducing herbicidal injury to direct-seeded rice caused by 2-chloro-2',6'-diethyl-N-(butoxymethyl)acetanilide.
| 2
|
FIELD OF THE INVENTION
The invention is directed to a warp knitting machine having at least one guide bar whose guides are carried by piezoelectrically controlled bending transducers and having a control arrangement comprising a computer and potential generator which, in accordance with a desired pattern, provides the bending transducer, via at least one control lane with sufficient potential to displace it by one needle space.
BACKGROUND OF RELATED ART
In a known warp hitting machine of this type (U.S. Pat. No. 5,390,512 issued Feb. 21, 1995 to Mists), the piezoelectric bending transducers are provided with an electrode and a control line. By the application of the control potential the guide is moved out of its neutral position and displaced by one needle space into the working position. The control lanes are brought together into a wiring harness and attached to one or both ends of the jacquard guide bar. Based upon stored pattern values the computer generates a signal for each working cycle in dependence upon a rotational angle signal read from the main shaft which, by means of a direct current converter is converted into control potentials in the lower potential zone.
Such an arrangement is suitable for slow running or small warp knitting machines with a low number of piezoelectric bending transducers pattern. It is only in such arrangements that it is possible to control the bending transducers, in accordance with the desired pattern, within the predetermined section of the working cycle.
In DE OS 40 17 482, there is disclosed a switching arrangement for the pattern control of electromagnetic setting members of a textile machine, in particular a jacquard arrangement of a weaving machine. There are provided a plurality of serial/parallel converters in which a cycle line, a data line and a reset line are common. Each serial/parallel converter has a data shift register whose outputs are led to the electronic setting members.
SUMMARY OF THE INVENTION
In accordance with the illustrative embodiments demonstrating features and advantages of the present invention, there is provided a warp knitting machine having at least one guide bar, and a plurality of guides. Also included is a plurality of piezoelectric bending transducers mounted on the guide bar for deflectably supporting the guides. Each of the transducers has a control line for producing in response to control potential thereon, a displacement over one needle space of the guides. The warp knitting machine also has a control arrangement coupled to the control lines for establishing a predetermined pattern with a computer, a potential generating means and a plurality of serial to parallel converters. The computer has a common data and command bus. The potential generating means can provide, in dependence upon the predetermined pattern, a control potential to the control lines. The potential generating means has a plurality of serial to parallel converters distributed over the full width of the warp knitting machine. The converters have (a) a plurality of data and command inputs connected to the common data and command bus, and (b) a plurality of outputs connected through the control lines to the bending transducers. The serial to parallel converters can store some data sent sequentially along the bus and upon the occurrence of a switching command from the computer simultaneously release stored data by applying the control potential to data-selected ones of the control lines.
A preferred embodiment of the present invention employs thread guides carried by piezoelectrically controlled bending transducers, which can be displaced in dependence on the pattern in larger and/or more rapidly running warp knitting machines with a higher degree of running certainty.
Preferably, a potential generator provided to a guide bar has a plurality of serial to parallel converters, whose data and command inputs run over a common data or command bus and are connected with a computer. The outputs of the converters are connected to the bending transducers via the control lines. The serial to parallel converters sequentially take up the data and upon the appearance of a switching command in the form of control potential, surrender them simultaneously. The serial to parallel converters are preferably attached to and distributed over the width of the machine.
This construction ensures that all the bending transducers are activated at the same point in time. This is determined by a switching command, which is, suitably, generated in dependence upon the rotational angle position of the main shaft. Practically the entire remainder of the working cycle is available for reading the data into an intermediate storage means of the serial to parallel converter.
Thus, it is possible to provide trouble-free operation even with faster running warp knitting machines and those with a very large number of bending transducers. Since serial to parallel converters of the type to be considered herein can only dispose of a limited number of data with a limited number of outputs, a substantial number of such transducers is required for each guide bar. However, since sufficient time is available for the task, these can be sequentially provided with data over a common data bus, wherein the data intended for each transducer can be provided with a predetermined address for that particular transducer.
The distributed arrangement of the transducers over the width of the machine makes it possible to keep all control lines comparatively short and to give them substantially the same length. In this way, the length of the control lines, which can lead to switching delays, can be held small and is the same for all of the bending transducers.
It is preferred to utilize high voltage, serial to parallel converters which yield a control potential of at least 200 volts. Such a potential can equally be supplied to the individual converters over a common bus line. The level of the potential permits the use of relatively small and thus capacity-poor bending transducers, which can be rapidly and securely switched.
It is further desirable that each serial to parallel converter is connected to the appropriate control line via a series resistor. This resistor limits the loading and unloading current for each bending transducer. It is so chosen that all of the bending transducers apply to the same circumstances, in particular the same switching speed.
It is further advantageous to provide that the data and command inputs of each serial to parallel converter are connected with a common bus via an optical coupler. The optical couplers protect the computer if there is a short circuit in the bending transducers.
It has been found particularly advantageous to provide the serial to parallel converters in individual structural assemblies, which are detachably affixable to a transom fixed to the machine. For this purpose each assembly is connected via an input plug connection to the bus and via an output plug connection to the control lines leading to the bending transducers of a guide set. Such a type of construction is very rapidly assembled and exchanged. Since the structural assemblies for each serial to parallel converter of a warp knitting machine can be the same, only a small spare parts storage is required. To correct failures, the assemblies can be repaired in a repair shop.
It is further advantageous that each bending transducer is provided with two differentiably activatable electrodes and thus each bending transducer is designated to two outputs of a serial to parallel converter. Such a bending transducer can be moved from a central at-rest position by means of the application of a control potential into either a left or a right working position in which, during power activation, they lie against a stop means. This provides a high positional security coupled with a relatively small bending of the bending transducer.
It is particularly advantageous to provide each assembly with a serial to parallel converter having 64 outputs and two output plug connections for each of the 32 control lines. Each set of sixteen bending transducers are thus provided to a guide set which is designated to the output plug connection. This guide set can similarly form a structural assembly which, after separation of the plug connection, may be disconnected from the guide bar.
It is also advantageous to provide that the serial to parallel converter possesses a group of switchable P-channels and a group of switchable N-channels, wherein a pair of P- and N-channels contains a common output, while their data inputs are connected with each other via an inverter. In accordance with choice, either the P- or the N-channels are activated at the output. By inversion of the data in the inverter, it is sufficient to provide each pair with only one bit for control. Furthermore, where there is separate control, the presence of the inverter prevents the possible short circuits between both channels.
In a desirable alternative, the serial to parallel converter comprises a group of switchable P/N channels, whose outputs are pair-wise provided to a single bending transducer; whereby the data input of each pair can be mutually connected by means of an inverter. Also here, by the use of an inverter, it is possible to reduce the amount of information to one bit per pair.
It is further advantageous to provide to each bending transducer, a strip-formed, electrically non-conductive carrier, which carries on each side, an inner electrode connected to an output of a serial to parallel converter, a piezoelectrically active layer, and a grounded outer electrode. Because of this grounded outer electrode, such a bending transducer is contact-safe which, in conjunction with the high control potential, is exceedingly useful.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is further illustrated by reference to the accompanying drawings illustrating the preferred embodiments, wherein:
FIG. 1 is a schematic, side elevational representation of a warp knitting machine according to the principles of the present invention, and including a schematic of a control arrangement;
FIG. 2 is a portion of the warp knitting machine of FIG. 1 viewed in front elevation;
FIG. 3 is schematic representation of a portion of a serial to parallel converter of FIG. 1 and 2 for a bending transducer;
FIG. 4 is a schematic representation of a structural assembly with attached bending transducers that may be employed in the arrangement of FIG. 2;
FIG. 5 is a schematic representation of a different serial to parallel converter portion, which is an alternate to that of FIG. 3;
FIG. 6 is a schematic representation of structural assembly of the control arrangement with attached bending transducers, which is an alternate to that of FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, the warp knitting machine (1) illustrated in FIG. 1 comprises a machine frame (2) having a main shaft (3) as well as a knitting needle bar (4) (illustrated schematically). A rotational angle measuring means (5) provides a rotational angle signal over line (6).
Three guide bars (7,8 and 9) are equipped with guides (10, 11 and 12) which, as is conventional, are swingable to and fro from an underlap position to an overlap position and back, as well as a displacement arrangement (13) for shogging them over one or more needle spaces parallel to needle bar (4).
The guides (10) are rigidly affixed to guide bar (7). These serve for the production of the ground fabric. The guides (11) are connected to the appropriate guide bar via bending transducers (14) as are guides (12) via bending transducers (15). By means of the bending transducers, the guides can be displaced by one needle space, thus serving the pattern formation of the fabric.
A control arrangement (16) is provided for the activation of these bending transducers. This comprises a main computer (17) provided with a pattern storage means (18), as well as subordinate computers (19 and 20) for each guide bar (8 and 9). The computer (19) is connected with input (22) of a high voltage serial to parallel converter (23). This possesses an intermediate storage means (24) in the form of a shift register into which the particular data for displacing the bending transducer (14) are read in sequentially. Each bending transducer (14) is connected to the outputs (26) of the high voltage serial to parallel converter by two control lines (25). These control lines serve to provide the control potential to the bending transducer generated by the potential control arrangement (27). For this purpose, connecting extension channels (28) are provided, which activate the accumulated data in intermediate storage means (24) when the rotational angle signal given off by line (6) reaches a particular value. The high voltage serial to parallel converter (29) for guide bar (9) is constructed in a similar manner.
High voltage serial to parallel converters are commercially available. However, they only have a limited number of outputs, for example 64 outputs. For this reason, as shown in FIG. 2, a substantial number of such high voltage serial to parallel converters (23.1 to 23.3) are distributed over the machine width. The inputs of converters (23.1 to 23.3) lie on a common bus (21) and are responsible for two sets of guides (e.g., sets 30 and 31) of sixteen bending transducers (14) each.
Each of these high voltage serial to parallel converters is part of a structural assembly (32) which is fastened to a transom (33) above guide bar (8) in a readily detachable manner and are covered by a housing (33.1). This structural assembly (32) comprises a printed circuit board (34) on which converter (23.1) is provided as an integrated circuit chip. A plug-type, input connector (35) connects the input of the converter with a bus (21). Two plug-type, output connectors (36 and 37) each serve as connections for thirty two output lines (25) which are taken together to form two wire harnesses (38 and 39). The plug connections permit this assembly (32) to be readily installed and dismounted.
The plug portions (40) of the output plug combination (36 and 37) are connected to the transom (33) by means of a releasable screw (41). The guide segments (30 and 31) are similarly releasably fastened to guide bar (8). Thus, it is equally simple to attach and remove the guide segments.
As may be seen from FIG. 2, the structural assemblies (32) are attached next to each other with some separation on transom (33). Thus, wire harnesses (38 and 39) and equally output line (25) have substantially the same, short length. Clamping arrangements (42) on plug portion (40) and clamping arrangement (43) on needle segments (30 and 31) serve to reduce tension load.
As illustrated in FIG. 3, the bending transducer (14) for the guide (11) has, suitably, the following construction: A strip-formed carrier (44) of electrically insulating material is coated on each side thereof with an inner electrode (45 and 46), which itself is coated with a piezoelectric layer (47 and 48, respectively) and again respectively covered with an outer electrode (49 and 50). The inner electrodes (45 and 46) are connected with the output lines (25.1 and 25.2), the outer electrodes (49 and 50) are connected to ground.
In FIG. 3, it is further illustrated that each bending transducer (14) has two switchable P/N channels (P/N 1 and P/N 2 ). These can be switched in either direction, depending upon the provision of current to one or the other. Their outputs run via serial resistors (51.1 and 51.2) to output lines (25.1, 25.2).
The common bus (21) comprises a plurality of common lines. A supply line (52) is arranged to provide the necessary control potential to the high voltage serial to parallel converter, suitably +5 volts. A potential control line (54) is connected with the potential control arrangement (arrangement 27 in FIG. 1) and provides, for example, a potential of +220 volts. A ground line (55) is connected to ground (51).
A data line (53) provides a path from the computer for the necessary data for the displacement of the bending transducer, namely, the addresses of the individual high voltage serial to parallel converters, as well as the switching commands for release of the stored data. The data input (22.1) of channel P/N 1 is connected to the data input (22.2) to the P/N 2 channel via an inverter (56) to act as a counteracting pair. This has the consequence that, as desired, the left inner electrode (45) or the right inner electrode (46) is provided with control potential while the other inner electrode is grounded. In the first case, the guide swings to the left; in the second case to the right.
FIG. 4 shows how a data line (58) over which data and addresses are transmitted from the computer, are coupled via an optical coupler (60,61) through a common bus (21) or a branch thereof. A command line (59) controls the input and output of the data. Coupler (60,61), also referred to as an optical coupling means, prevents any short circuits that might occur in the bending transducers from having a disadvantageous impact upon the computer.
Furthermore, it may be seen that the switchable channels P/N 1 through P/N 32 are coupled to the guide segments (30), (comprising sixteen guides) and switchable channels P/N 33 through P/N 64 are coupled to guide segment (31) (comprising sixteen guides). Guide segments 30 and 31 are connected to channel sets 62 and 63, respectively.
FIG. 5 shows a further embodiment which can be distinguished from that of FIG. 3 in that for each output line (25.1 and 25.2) of bending transducer (14) there is provided a pair of switchable channels, namely, a P-channel (P 1 and P 2 ) and an N-channel (N 1 and N 2 ). In this case, the bus (21) possesses a supply line (64) for a positive energization potential, a supply line (65) for a negative energization potential, a data line (66), and a control potential supply line (67) for a positive control potential, for example +220 volts. Bus (21) also has a control potential supply line (68) for a negative control potential of, for example, -30 volts.
For each complementary pair of P- and N-channels, the data inputs (69.1 and 69.2) are mutually connected via an inverter (70). This ensures that only one of the two channels is active at any one time.
In this switching mode, one of the inner electrodes (45, inset of FIG. 3) of a bending transducer (14) is provided with a positive control potential and the outer electrode (46) with a negative control potential. This leads to a rapid transition.
In FIG. 6, a variant of FIG. 4 is illustrated with the dotted boxes (71,72) showing switchable channels P 1 through P 32 and N 1 to N 32 coupled to guide segment (30); and switchable channels P 33 through P 64 and N 33 through N 64 coupled to guide segment (31).
As the high voltage, serial to parallel converters with switchable P/N channels in accordance with FIG. 4, there may be used the type HV35, manufactured by Supertex Incorporated, Central U.S., 1200 Country Club Lane, Street 102, Fort Worth, Tex. 76112 and for switchable P-channels and N-channels, in accordance with FIG. 6, the type HV49 and HV31 from the same company are utilized.
|
In a warp knitting machine at least one guide bar (8,9) carries piezoelectric bending transducers (14,15) to which are attached guides (11,12). A control arrangement (16) comprises a computer (17,19,20) and a potential generator, which provide the control potential via control lines (25) to the bending transducers. The potential source provided to a guide bar (8,9) comprises a plurality of serial to parallel converters (23) whose data and command inputs (22) are connected via a common data and command bus (21) with the computer and whose outputs (26) are connected with the bending transducers via the control lines (25). The serial to parallel converters (23) take up the data sequentially and upon occurrence of the switching command transmit them simultaneously in the form of control potentials. In this way rapidly running and/or large warp knitting machines can be provided with a operative piezoelectric jacquard control.
| 3
|
FIELD OF THE INVENTION
[0001] The present invention relates to an axle driving apparatus for improving the straightforward running capacity of a vehicle on a muddy road or the like, and more particularly to an axle driving apparatus which is integrally provided with a hydrostatic transmission (hereinafter referred to as the HST); axles; a power transmitting mechanism, which can easily change the speed of the HST; an oil reservoir, which can absorb an increase in the volume of oil due to an increase in the temperature of the HST; and a differential locking device, all of which are provided in a single housing.
BACKGROUND OF THE INVENTION
[0002] Conventionally, an axle driving apparatus consists of a housing for an HST, axles and a power transmitting device for interconnecting the HST and axles. On the center section of the HST is disposed a hydraulic pump, provided with a vertical input shaft, and a hydraulic motor, provided with a horizontal output shaft. A plurality of pistons are disposed in the hydraulic pump cylinder block. The heads of the pistons abut against a movable swash plate. Changing the angle of the movable swash plate changes the pump capacity so as to increase or decrease the number of rotations of the hydraulic motor. The movable swash plate is slanted, thereby enabling the speed of the HST to be changed by rotatably operating trunnions supported in the housing. Each trunnion is disposed on a longitudinally slanted axis of the swash plate, as disclosed in U.S. Pat. No. 5,456,068, for example.
[0003] A speed change controller, such as a pedal or a lever, which is provided on the vehicle can be operated normally longitudinally thereof so that its motion can be transmitted to a control arm of the axle driving apparatus through a link mechanism, such as a rod, disposed longitudinally of the vehicle. Hence, it is preferable that the control arm swing longitudinally around the lateral axis. One conventional construction is provided with a vertical operating shaft, independent of the trunnions, where both trunnions and the vertical operating shaft interlock with each other. The control arm is provided at one end of the operating shaft so that the control arm swings longitudinally around the vertical axis, and the other end is constructed so that the trunnion projects at the axial end thereof from the front wall of the housing. A control arm is provided at the axial end so that the control arm swings laterally around the longitudinal axis. A complex linkage mechanism, with respect to the vertical operating shaft and trunnions, is required in the first construction described above, thereby increasing the number of parts and assembly time, making the axle driving apparatus too expensive to produce. The second construction described above requires a separate link mechanism for converting the longitudinal motion into a lateral motion, thereby requiring space to provide two link mechanisms in the vehicle, making it difficult to apply the apparatus to a vehicle of small size and increasing the number of parts required.
[0004] U.S. Pat. Nos. 5,440,951 and 5,515,747 disclose that when the HST and the mechanism for transmitting power to the axles from the HST are housed in the same housing, the housing can be filled with oil to be used as both operating oil for the HST and lubricating oil for the transmitting mechanism. In this case, a foreign object, such as iron powder, created by the rubbing of the transmitting mechanism may flow toward the HST. The iron powder or other foreign object is removed by an oil filter so as not to enter into the HST closed fluid circuit. However, the iron powder or the like may encroach on the piston and swash plate and thereby adversely affect them. The housing is integrated in part with the oil reservoir so as to enable the oil volume in the housing to be adjusted when expanded due to a rise in temperature. However, the greater the quantity of oil, the larger the increase in volume. Thus, the housing must be made larger and the reservoir therefore becomes larger so that the housing itself has to be large in size.
[0005] U.S. Pat. No. 5,094,077 discloses that in order to prevent the speed change controller equipped on the vehicle from being hastily operated by an operator, a shock absorber is provided on the control arm. The shock absorber should be disposed above the upper wall of the housing because the control arm is configured to vertically and longitudinally swing around the axis on the upper wall of the housing. Therefore, space for disposing the shock absorber without interference with an input pulley or an enlarged portion of the upper wall of the housing is required.
[0006] Further, where a differential gear is provided between the left and right axles, when one axle is idling, a driving force cannot be transmitted to the other axle. Hence, it is desired to provide a differential locking device on the axle driving apparatus for integrating the differential locking device with the HST and the axles.
SUMMARY OF THE INVENTION
[0007] The axle driving apparatus of the present invention is partitioned by an internal wall provided within the housing, into a first chamber for housing therein the HST and a second chamber for housing therein axles and a transmitting mechanism which transmits power from an output shaft of the HST to the axles. Both chambers are filled with common oil. An oil filter is disposed therebetween to allow the chambers to communicate with each other. One chamber communicates with an oil reservoir. Trunnions for the swash plate to change the output rotation of the HST are supported between the internal wall and a side plate fixed to the housing. The trunnions are disposed laterally of and in parallel to the axles. One of the trunnions projects outwardly from the housing so as to fix an arm. The shock absorber is connected thereto, thereby preventing hasty speed change. A differential locking device is attached to a differential gear differentially connecting the left and right axles. During the normal running of the vehicle, the differential rotation can be performed. When one axle is idling, both axles are adapted to be directly connected to each other.
[0008] These and other objects of the invention will become more apparent from the detailed description and examples which follow.
BRIEF DESCRIPTION OF THE FIGURES
[0009] [0009]FIG. 1 is a plan view of an axle driving apparatus;
[0010] [0010]FIG. 2 is a partially sectional plan view of the same in which an upper half housing thereof is removed;
[0011] [0011]FIG. 3 is a sectional view looking in the direction of arrows 3 - 3 in FIG. 2;
[0012] [0012]FIG. 4 is a sectional view looking in the direction of arrows 4 - 4 in FIG. 2;
[0013] [0013]FIG. 5 is a sectional view looking in the direction of arrows 5 - 5 in FIG. 2;
[0014] [0014]FIG. 6 is a sectional view looking in the direction of arrows 6 - 6 - in FIG. 2;
[0015] [0015]FIG. 7 is a sectional view looking in the direction of arrows 7 - 7 in FIG. 2;
[0016] [0016]FIG. 8 is an enlarged sectional plan view of a principal portion of the mechanism of a braking device;
[0017] [0017]FIG. 9 is an enlarged sectional side view of a principal portion of the same;
[0018] [0018]FIG. 10 is a enlarged sectional view of only a part of a principal portion of the same;
[0019] [0019]FIG. 11 is a left side view of a center section of the present invention;
[0020] [0020]FIG. 12 is a plan view of the same;
[0021] [0021]FIG. 13 is a sectional view looking in the direction of arrows 13 - 13 in FIG. 11;
[0022] [0022]FIG. 14 a sectional view looking in the direction of arrows 14 - 14 in FIG. 11;
[0023] [0023]FIG. 15 is a sectional view looking in the direction of arrows 15 - 15 in FIG. 11;
[0024] [0024]FIG. 16 is a sectional view looking in the direction of arrows 16 - 16 in FIG. 12;
[0025] [0025]FIG. 17 is a sectional view looking in the direction of the arrows 17 - 17 in FIG. 12;
[0026] [0026]FIG. 18 is a sectional view looking in the direction of the arrows 18 - 18 in FIG. 12;
[0027] [0027]FIG. 19 is a sectional view looking in the direction of the arrows 19 - 19 in FIG. 12;
[0028] [0028]FIG. 20 is a sectional view looking in the direction of the arrows 20 - 20 in FIG. 12;
[0029] [0029]FIG. 21 is a bottom plan view of the center section from which the charge pump has been removed;
[0030] [0030]FIG. 22 is sectional view of a differential gear and a differential locking device;
[0031] [0031]FIG. 23 is a side view of a slider of the differential locking device;
[0032] [0032]FIG. 24 is a side view of a ring gear of the same; and
[0033] [0033]FIG. 25 is a perspective exploded view of the differential gear of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] FIGS. 1 - 7 show the construction of an axle driving apparatus. The housing of the axle driving apparatus comprises an upper half housing 1 and a lower half housing 2 joined to each other along a horizontal, flat joint surface along the periphery of the upper and lower half housings 1 , 2 . A bearing for a motor shaft 4 is provided on the joint surfaces of both upper half housing 1 and lower half housing 2 . Bearings for axles 7 are shifted upwardly from the joint surface of both upper half housing 1 and lower half housing 2 and are disposed in upper half housing 1 to rotatably support axles 7 . Axles 7 are differentially connected by a differential gear unit 23 and project laterally outwardly of the housing.
[0035] The interior of the housing is partitioned by an internal wall 8 into a first chamber R 1 for housing therein an HST and a second chamber R 2 for housing therein a gear-type drive train which transmits power to differential gear unit 23 from motor shaft 4 to axles 7 . First chamber R 1 and second chamber R 2 are filled with common oil which forms an oil sump. As shown in FIG. 7, an oil feed lid 6 is provided on an upper wall of upper half housing 1 above differential gear unit 23 . The housing can be filled with operating oil through lid 6 . As shown in FIG. 6, an oil flow port 75 is provided in the upper portion of upper half housing 1 . Upper half housing 1 communicates through a piping 9 , of rubber hose or the like, with the interior of an oil reservoir 10 mounted at a predetermined position on the vehicle, thereby enabling the volume of operating oil in oil reservoir 10 to be adjusted.
[0036] As shown in FIG. 6, an oil bore 8 a is open at a predetermined position in internal wall 8 which partitions first chamber R 1 from second chamber R 2 . An oil filter 18 covers oil bore 8 a . In this embodiment, as shown in FIGS. 2 and 6, oil bore 8 a and oil filter 18 are disposed on internal wall 8 between the portion containing the HST and the portion containing the right side axle 7 , thereby enabling oil to flow between first chamber R 1 and second chamber R 2 through oil filter 18 . Accordingly, oil filling the housing can be used as both operating oil for the HST and lubricating oil for the gears and bearings. When the oil enters into first chamber R 1 from second chamber R 2 , foreign objects such as iron powder which are harmful to the HST, are filtered by oil filter 18 .
[0037] Internal wall 8 is provided within the housing so that first chamber R 1 is disposed in front of axles 7 and to the side of the drive train for transmitting power from motor shaft 4 to differential gear unit 23 . Internal wall 8 , as shown in FIG. 4, comprises (1) an internal wall portion 1 a erected integrally with the upper inner surface of upper half housing 1 and is positioned at the end surface on the same plane as the joint surface of the housing parts 1 , 2 and (2) an internal wall portion 2 a erected integrally with the inner bottom surface of lower half housing 2 and positioned at the end surface on the same plane as the joint surface of the housing. When both upper half housing 1 and lower half housing 2 are joined together, the end surfaces of both internal wall portion 1 a and internal wall portion 2 a join each other to form internal wall 8 , thereby partitioning the interior of the housing into first chamber R 1 and second chamber R 2 .
[0038] The HST is housed in first chamber R 1 . The HST comprises a hydraulic pump P, a hydraulic motor M and a center section 5 . Center section 5 is elongated and is longitudinally disposed in first chamber R 1 . A vertical surface 91 is formed at the front of center section 5 on which hydraulic motor M is disposed. A horizontal surface 90 is formed along the top of center section 5 on which hydraulic pump P is disposed. A pump shaft 3 is substantially vertically disposed on center portion 5 and is positioned between motor shaft 4 and axles 7 which extend substantially horizontally and in parallel to each other. A pump mounting surface 40 is formed on horizontal surface 90 of center section 5 for hydraulic pump P. A cylinder block 16 is rotatably and slidably disposed on pump mounting surface 40 . Pistons 12 are fitted into a plurality of cylinder bores in cylinder block 16 and are reciprocally movable by biasing springs. The heads of pistons 12 abut against a thrust bearing 11 a held to the movable swash plate 11 . At the center of movable swash plate 11 , an opening 11 b is provided through which pump shaft 3 perforates. Pump shaft 3 , used also as an input shaft, is disposed on the rotary axis of cylinder block 16 and is fixed thereto as that pump shaft 3 and cylinder block 16 rotate together. Pump shaft 3 projects at the upper axial end thereof outwardly from the upper wall of upper half housing 1 . An input pulley 43 with a cooling fan 44 is fixed to pump shaft 3 . Input pulley 43 is given power from a prime mover (not shown) through a belt transmitting mechanism (not shown).
[0039] As seen in FIG. 6, the piston abutting surface of movable swash plate 11 is disposed perpendicular to the rotary axis of cylinder block 16 . Movable swash plate 11 is shown in the neutral position. Movable swash plate 11 can be tilted from side to side so as to enable the discharge amount and discharge direction of oil from hydraulic pump P to be changed. As seen in FIG. 4, for example, movable swash plate 11 is integrally provided with trunnions 35 L and 35 R, which project laterally from both sides of swash plate 11 and are disposed in parallel to axles 7 . Movable swash plate 11 , as shown in FIGS. 2 and 4, is slantingly rotatably supported between the two parallel walls of internal wall portion 1 a in upper half housing 1 and the side wall of the upper half housing 1 . A recess 1 b is bored in the side surface of internal wall portion 1 a . Recess 16 has an inner diameter about equal to the outer diameter of a bearing bush fitted on trunnion 35 L. As best seen in FIG. 4, trunnion 35 L is rotatably supported in recess 1 b . In order to bore recess 1 b in internal wall portion 1 a , an opening 1 c is formed in the side wall of upper half housing 1 . A machining tool for boring recess 1 b is inserted into upper half housing 1 through opening 1 c . A side plate 15 for closing opening 1 c is detachably fixed onto the outer surface of the side wall of upper half housing 1 through sealing members (not shown). Trunnion 35 R extends into a hollow cylindrical portion integrally formed in side plate 15 so as to be rotatably supported therein. Movable swash plate 11 is longitudinally tilted around trunnions 35 L and 35 R within first chamber R 1 , enabling the output of hydraulic pump P to be changed.
[0040] At the outer surface of side plate 15 , a plurality of fins 15 a (see FIG. 3) for receiving cooling wind from cooling fan 44 are disposed in the direction of the flow of the cooling wind. Wind blowing across fins 15 a lowers the temperature of oil stored in first chamber R 1 .
[0041] The axial end of trunnion 35 R projects outwardly from side plate 15 . A control arm 38 (discussed below) is fixed onto the axial end and is connected through a link or wire (not shown), to a speed change lever mounted at the driver's seat of the vehicle, so as to rotate around the lateral axis of the vehicle body. This simplifies the transmitting mechanism for slantwise control of movable swash plate 11 . A neutral return coiled spring 31 is fitted onto trunnion 35 R in first chamber R 1 . Both ends of neutral return coiled spring 31 project forwardly between an engaging pin 39 and around an eccentric shaft 33 mounted onto the inner surface of side plate 15 (see FIG. 2). Engaging pin 39 projects from an arm 11 d which projects forwardly from movable swash plate 11 .
[0042] Accordingly, when control arm 38 is rotated in order to change the speed of the vehicle, arm 11 d rotates together therewith and one end of neutral return coiled spring 31 moves away from the other end toward engaging pin 39 . The other end of neutral return coiled spring 31 is retained by eccentric shaft 33 so as to apply a biasing force to control arm 38 which tends to return to the neutral position. When the operating force to the speed change lever is released, the restoring force created at one end of neutral return coiled spring 31 returns engaging pin 39 toward eccentric shaft 33 so as to be held in a neutral position. A portion of eccentric shaft 33 extending outwardly from side plate 15 is fixed thereto through an adjusting nut 33 a , which can be released to properly rotatably shift eccentric shaft 33 , thereby shifting arm 11 d around trunnion 35 R through neutral return coiled spring 31 . This enables movable swash plate 11 to be adjusted to the accurate neutral position.
[0043] Control arm 38 is fixed to the end of trunnion 35 R which extends outside of the housing, as shown in FIG. 3. Control arm 38 is substantially V-shaped, with a first retaining portion 38 a and a second retaining portion 38 b . First retaining portion 38 a projects upwardly to connect with a speed changing member such as a lever or pedal (not shown), and with trunnion 35 R when the speed change force is applied. Second retaining portion 38 b projects slantwise rearwardly of the vehicle to connect with one end of a movable portion 73 a of a shock absorber 73 . Shock absorber 73 and control arm 38 are formed to straddle right axle 7 . The base of a fixed portion 73 b of shock absorber 73 is pivotally supported to a mounting pin 74 b . Mounting Pin 74 b is mounted to the rear end of a support plate 74 fixed through mounting bolts 74 a to the lower surface of a sleeve for right axle 7 . Thus, shock absorber 73 connects with control arm 38 so as to prevent a rapid speed change operation. Further, the operating force of the speed changing member, when released, does not rapidly return swash plate 11 to its neutral position, due to the spring force of neutral return coiled spring 31 . This prevents an abrupt stop of the vehicle caused by the braking action of the HST.
[0044] Because shock absorber 73 is disposed longitudinally along one side of the housing, it is not necessary to consider the height of input pulley 43 or an enlarged portion of the housing. A reasonable connection and arrangement is provided allowing control arm 38 to be swung along a lateral axis of the apparatus.
[0045] Pressure oil from hydraulic pump P is sent to hydraulic motor M through an oil passage in center section 5 . Hydraulic motor M, as shown in FIG. 5, is constructed so that a motor mounting surface 41 is formed along vertical surface 91 of center section 5 . A cylinder block 17 is rotatably slidably mounted to motor mounting surface 41 . A plurality of pistons 13 are reciprocally movably inserted into a plurality of cylinder bores in cylinder block 17 through biasing springs. A thrust bearing, held to a fixed swash plate 37 , abuts against the heads of pistons 13 . Fixed swash plate 37 is fixedly positioned between upper half housing 1 and lower half housing 2 . Motor shaft 4 is disposed on the rotary axis of cylinder block 17 and is fixed thereto so that motor shaft 4 and cylinder block 17 move together. One end of motor shaft 4 is supported in a shaft bore provided at the center of motor mounting surface 41 of center section 5 . The other end of motor shaft 4 perforates through internal wall 8 , formed at the joint surface of upper half housing 1 and lower half housing 2 , so as to enter into second chamber 2 . Motor shaft 4 is rotatably supported by a bearing 76 fitted into internal wall 8 . Bearing 76 includes an oil-tight seal in order to partition first chamber R 1 and second chamber R 2 . In particular, an O-ring 77 is provided on the outer periphery of bearing 76 .
[0046] A brake disc 19 is fixed to one axial end of motor shaft 4 positioned in second chamber R 2 . As shown in FIG. 9 a brake pad 98 is fitted into the inner surface of upper half housing 1 positioned at one side of the upper portion of brake disc 19 . At the opposite side of brake disc 19 , a brake operating shaft 97 is supported which perforates the wall of upper half housing 1 from the outside to the inside thereof through a support plate 92 . Brake pad 98 and the end surface of brake operating shaft 97 are opposite to each other. Brake disc 19 is sandwiched therebetween. Brake operating shaft 97 is supported in parallel to motor shaft 4 . A brake arm 93 is fixed to the end of brake operating shaft 97 outside of the housing. A spring 94 is fitted onto brake operating shaft 97 between brake arm 93 and support plate 92 , so as to bias the end surface of brake operating shaft 97 away from brake disc 19 .
[0047] A flange 97 a is formed within the housing at one end of brake operating shaft 97 . A plurality (four in this embodiment) of groves 97 b are provided at the surface of flange 97 a facing the inner surface of the housing. Cam grooves 92 a , each V-shaped in cross-section and arcuate when viewed in plan are provided at the end surface of support plate 92 , opposite to grooves 97 b . As shown in FIG. 10, balls 95 are interposed between cam grooves 92 a and grooves 97 b . In such construction, when brake arm 93 is rotated, brake operating shaft 97 rotates along its longitudinal axis. Balls 95 , held by recesses 97 b , slowly ride onto the shallowest portions of cam groove 92 a from the deepest portions thereof. This causes brake operating shaft 97 to slidably move, due to the thrust generated thereon by balls 95 , toward brake disc 19 thereby sandwiching brake disc 19 between brake pad 98 and the end surface of brake operating shaft 97 so as to brake motor shaft 4 . Flanges 92 b , which extend radially and are V-shaped, are integrally provided at the outer end of support plate 92 (see FIG. 8). Elongate slots 92 c , which are oval-arcuate shaped are open in flanges 92 b around brake operating shaft 97 . Bolts 96 are inserted into elongate slots 92 c , thereby fixing support plate 92 onto the outer surface of the side wall of upper half housing 1 . Bolts 96 may be unscrewed to properly rotate flanges 92 b around brake operating shaft 97 , thereby enabling balls 95 to adjust the length of time during which balls 95 ride on cam groove 97 b.
[0048] Next, explanation will be given on the construction of center section 5 for loading thereon hydraulic pump P and hydraulic motor M in accordance with FIGS. 11 through 21. Center section 5 is longitudinally elongated and is provided at one side thereof with a bolt bore 5 h and at another side thereof with two bolt bores 5 h . Three mounting bolts are inserted into bolt bores 5 h and are used to fix center section 5 to the inner wall of upper half housing 1 in first chamber R 1 . At the center of pump mounting surface 40 and at the rear and upper surface of upper half housing 1 is formed a bearing bore for rotatably supporting the lower end of pump shaft 3 . A pair of arcuate ports 40 a and 40 b are open longitudinally through center section 5 around a bearing bore. Feed or discharge oil is communicated with cylinder block 16 through parts 40 a and 40 b . At the center of motor mounting surface 41 , vertically disposed in front of pump mounting surface 40 , is bored a bearing bore for rotatably supporting one end of motor shaft 4 . A pair of arcuate ports 41 a and 41 b are open vertically and around the bearing bore, thereby communicating feed or discharge oil with cylinder block 17 .
[0049] In order to connect arcuate ports 40 a and 40 b at pump mounting surface 40 with arcuate ports 41 a and 41 b at motor mounting surface 41 , a first linear oil passage 5 a and a second linear oil passage 5 b are bored in a thick portion of center section 5 , in parallel to each other. As shown in FIG. 12, the center of pump mounting surface 40 is positioned along an imaginary vertical plane (line 16 - 16 ) disposed along motor mounting surface 41 . Half of cylinder block 16 mounted on pump mounting surface 40 (as shown in FIG. 2) overlaps, when viewed from above, with half of cylinder block 17 disposed on motor mounting surface 41 . This arrangement permits the HST and first chamber R 1 which contains the HST to be smaller in lateral width. A third linear oil passage 5 c communicates horizontally and perpendicularly with an intermediate portion of second oil passage 5 b . Arcuate port 40 a at pump mounting surface 40 , as shown in FIG. 18, is shallow and directly communicates with first oil passage 5 a . Arcuate port 40 b is deeper to communicate with third oil passage 5 c . Arcuate port 41 a at motor mounting surface 41 is deeper at the upper portion thereof to communicate with first oil passage 5 a and shallow at the lower portion thereof, as shown in FIGS. 16 and 17. Arcuate port 41 b communicates, at the lower portion thereof, with second oil passage 5 b . Thus, first oil passage 5 a communicates with arcuate port 40 a and with arcuate port 41 a , while second oil passage 5 b and third oil passage 5 c communicate with arcuate port 40 b and with arcuate port 41 b , so as to form a closed fluid circuit in center section 5 .
[0050] With reference to FIG. 17, check valves 54 and 55 are disposed at the open ends of first oil passage 5 a and second oil passage 5 b respectively. Both first oil passage 5 a and second oil passage 5 b are closed by plug members 64 a in which check valves 54 and 55 are disposed, respectively. The open end of third oil passage 5 c is closed by a plug member 64 b . Check valves 54 and 55 communicate at the inlet sides thereof with oil passage 5 d through oil bores 54 b and 55 b provided at casings 54 a and 55 a . The open end of oil passage 5 d is positioned in a recess 5 g formed at the lower surface of center section 5 . At the lower surface of center section 5 , opposite to pump mounting surface 40 , a charge pump casing 46 is mounted through a plurality of mounting bolts 69 . A trochoid-type charge pump 45 is housed (see FIG. 4) in a recess formed at a center of the upper surface of charge pump casing 46 . Trochoid-type charge pump 45 is provided with internal teeth and external teeth. The lower end of pump shaft 3 projects downwardly from center section 5 and engages with the external teeth so as to drive charge pump 45 . Charge pump 45 , however, may be of an external gear type or other known type.
[0051] As seen in FIGS. 18 and 19, charge pump 45 has a discharge port 45 a and an intake port 45 b . Intake port 45 b communicates with an opening 46 b (FIG. 17) into which the open end of a cylindrical oil filter 56 is inserted (see FIGS. 5 and 6). Oil filter 56 is disposed under hydraulic motor M in first chamber R 1 . Oil filter 56 is insertable into charge pump casing 46 which is in the housing from the exterior thereof through an insertion bore open at the front wall of lower half housing 2 . Oil filter 56 is interposed between charge pump casing 46 and a plug member 48 which closes the insertion bore at the front wall of lower half housing 2 . Plug member 48 can be removed to facilitate maintenance and inspection of oil filter 56 . A pair of oil joints 49 and 50 project from the a side surface of charge pump casing 46 (FIG. 13). The ends of joints 49 and 50 , as shown in FIG. 3, are exposed at a lower portion of the outside surface of lower half housing 2 . Oil joints 49 and 50 function as an oil pressure source for hydraulic actuators equipped outside of the vehicle.
[0052] Oil joint 50 is formed to serve as an oil takeout port and communicates with discharge port 45 a of charge pump 45 through an oil passage 46 a as shown in FIG. 13. A first relief valve 57 , for setting the oil pressure of discharge port 45 a , is housed in charge pump casing 46 and is connected to an oil passage 46 c which is branched from oil passage 46 a . Relief oil discharged from first relief valve 57 flows into recess 5 g at the lower surface of center section 5 through oil passage 46 c . Oil joint 49 is formed to be an oil return port and to communicate with recess 59 of center section 5 through oil passages 46 d and 46 e . A second relief valve 58 for setting the oil pressure in recess 5 g to be supplied to the closed circuit of the HST is housed in charge pump casing 46 and connects with recess 5 g through an oil passage 46 f . Relief oil discharged from second relief valve 58 is discharged outwardly from charge pump casing 46 through an oil passage 46 g.
[0053] As seen in FIG. 17, when charge pump 45 is driven, oil flowing into recess 5 g through the oil passage 46 c is adjusted by second relief valve 58 . This causes check valve 54 or 55 to open through oil passage 5 d at the low pressure side of one of oil passages 5 a , 5 b or 5 c , thereby forcibly supplying operating oil into the closed fluid circuit for the HST.
[0054] When the vehicle is stopped on a sloping surface, and the HST is put in the neutral position without the parking brake exerted, the force causing the driving wheels of the vehicle to roll acts on the closed fluid circuit of the HST to generate pressure so as to cause negative pressure in the closed fluid circuit and possibly causing the vehicle to move. In order to prevent such a phenomenon, a check valve 47 (see FIG. 15) is housed in charge pump casing 46 which can supply operating oil to the closed fluid circuit of the HST even when charge pump 45 is not driven. Check valve 47 communicates at the inlet side thereof with intake port 45 b through an oil passage 46 h and at the outlet side with recess 5 g through an oil passage 46 i . When charge pump 45 is driven to flow operating oil into recess 5 g though oil passages 46 c and 46 e , check valve 47 closes between oil passage 46 h and oil passage 46 i . When charge pump 45 is not driven, causing negative pressure on the low pressure side of the closed circuit, check valve 47 is open to enable oil filtered by filter 56 to be guided from intake port 45 b and oil passages 46 h and 46 i into recess 5 g . Check valve 54 or 55 , at the negative pressure side of the closed fluid circuit, is open through oil passage 5 d , whereby oil is supplied to the closed fluid circuit. Thus, oil can be maintained in the closed fluid circuit at all times.
[0055] In order to place operating oil into the closed fluid circuit after the axle driving apparatus is assembled, oiling pipes 52 and 53 are disposed at the lower surface of center section 5 as shown in FIGS. 11, 15, 17 and 20 . At the lower surface of center section 5 , a fourth vertical passage 5 e is bored to communicate with the upper deep portion of arcuate port 41 a . A fifth vertical oil passage 5 f is bored to communicate with second oil passage 5 b . Oiling pipes 52 and 53 are mounted into oil passages 5 e and 5 f respectively and are opened at the lower ends thereof outwardly from the bottom wall of lower half housing 2 and closed at the open ends by use of plug members after the closed fluid circuit is filled with operating oil.
[0056] As shown in FIGS. 2 and 5, a by-pass arm 60 for opening the interior of the closed circuit to the oil sump, in order to enable the axle to be idle during hauling of the vehicle, is disposed in the upper portion of upper half housing 1 . In particular, by-pass arm 60 is fixed at its base onto the upper end of a by-pass shaft 61 , which is vertically, rotatably and pivotally supported to the upper wall of upper half housing 1 . By-pass shaft 61 extends at its lower end into a thick portion of motor mounting portion 41 of center section 5 . A flat surface 61 a is formed at a part of the outer periphery of the lower end of by-pass shaft 61 . A through-bore 5 i (see FIG. 11) is open at motor mounting surface 41 of center section 5 slightly above the center thereof and between arcuate port 41 a and 41 b . A push pin 62 (see FIG. 5) is slidably supported into through-bore 5 i along the rotary axis of cylinder block 17 . One end surface of push pin 62 can abut against the rotary sliding surface of cylinder block 17 in close contact with the motor mounting surface 41 . The other end surface abuts against flat surface 61 a of by-pass shaft 61 .
[0057] Thus, when an operator operates a by-pass operating lever (not shown) equipped on the vehicle when the vehicle is hauled, by-pass shaft 61 is rotated through by-pass arm 60 . Push pin 62 is pushed toward cylinder block 17 by the flat surface of the lower end of by-pass shaft 61 . Push pin 62 moves the cylinder block 17 above motor mounting surface 41 . First oil passage 5 a and second oil passage 5 b communicate with the oil sump of the housing through arcuate ports 41 a and 41 b respectively, thereby enabling motor shaft 4 to freely rotate.
[0058] As shown in FIGS. 2 and 7, the drive train for transmitting power from motor shaft 4 to differential gear 23 is constructed with a gear 25 provided on a portion of motor shaft 4 entering into second chamber R 2 , for engaging with a larger diameter gear 24 , fixed onto a counter shaft 26 . A smaller diameter gear 21 is also fixed onto counter shaft 26 and engages with an input gear 22 . Power from motor shaft 4 is reduced in speed by gears 25 , 24 and 21 to drive differential gear unit 23 by input gear 22 . Larger diameter gear 24 , on counter shaft 26 , is disposed to the side of input gear 22 and overlaps in part therewith. Counter shaft 26 is rotatably housed in lower half housing 2 and is supported at both axial ends in a recess formed on the side wall of lower half housing 2 and a recess formed on the internal wall 2 a of lower half housing 2 , as shown in FIG. 2, so as to be rotatably supported when lower half housing 2 is joined with upper half housing 1 .
[0059] As best seen in FIGS. 2 and 22, the distal ends of axles 7 are rotatably supported by ball bearings in axle housing portions projecting from upper half housing 1 . The proximate end of each axles 7 is sleeved by a bearing bush. One half of each bearing bush is received in a recess in upper half housing 1 . The other half is received by a projection of lower half housing 2 which enters into upper half housing 1 . Axles 7 are rotatably supported to receive power transmitted through differential gear 23 . As shown in FIG. 2, the HST is disposed to the right side of the drive train. A control arm 38 for movable swash plate 11 is disposed to the right side of the HST. Hydraulic pump P is positioned substantially at the lateral and longitudinal center of the apparatus and is disposed so as to avoid the enlarged portion of differential gear 23 . This enables the housing to be compact.
[0060] Differential gear unit 23 is shown in FIGS. 22 through 25. As seen in FIG. 24, the center of input gear 22 has a shaft bore 22 a for receiving axles 7 therein. Bores 22 b for receiving differential pinions 80 and fitting-in bores 22 a for receiving the differential locking device are disposed at both sides of input gear 22 . Spline-fitted bevel-type output gears 81 L and 81 R are disposed at the proximate end of axles 7 . Spindles 80 a of the bevel-type differential pinions 80 are retained in bores 22 b of input gear 22 in which differential pinions 80 are also housed. Differential pinions 80 engage with output gears 81 L and 81 R so as to form differential gear unit 23 . No differential casing is otherwise provided. The differential locking device is provided opposite to the drive train at one side (preferably the right side) of differential gear 23 unit.
[0061] Between output gear 81 R and the proximate end of right axle 7 is interposed a collar 83 on which a slider 82 is axially slidably fitted. Slider 82 is cup-like shaped to wrap around output gear 81 R. At the outer peripheral side surface of slider 82 , projections 82 a are integrally provided. Projections 82 a are permanently engageable with insertion bores 22 c of input gear 22 . At the inner peripheral side surface of slider 82 are formed a plurality of projections 82 b which are engageable with a plurality of recesses 81 a formed in the outer periphery of output gear 81 R. An insertion groove 82 c is formed on the cylindrical portion of slider 82 opposite to projections 82 a , so as to fit the tip of a fork 84 into groove 82 . The base of fork 84 is slidably fitted onto a shaft 85 which is journalled to both side walls in lower half housing 2 . At the side surface of the base of fork 84 is formed a cam surface 84 a , which abuts against a pin 87 provided on shaft 85 so as to constitute a cam mechanism. An arm 86 is fixed to shaft 85 . Arm 86 projects outwardly from the housing so as to connect with a differential locking pedal (not shown) provided on the vehicle.
[0062] In such construction, when the operator presses the differential locking pedal, shaft 85 rotates through arm 86 , and pin 87 rotates to push to the right in the drawing of FIG. 22. As a result, cam surface 84 a abuts against pin 87 so as to slidably move fork 84 . At the same time, slider 82 slides, while maintaining projections 82 a in insertion bores 22 c of ring gear 22 . Projections 82 b engage with recesses 81 a of output gear 81 R and input gear 22 is differentially locked and coupled with axles 7 . As a result, axles 7 are uniformly driven when the vehicle runs on any road surface.
[0063] The axle driving apparatus of the present invention can be used for driving the axles of a vehicle to improve the operability of changing the speed of the vehicle. An example of a moving vehicle which may utilize the above-mentioned axle driving apparatus is a farm or other working vehicle, such as a tractor with a mower attachment, or other vehicle for transportation.
[0064] While one embodiment of the present invention has been shown and described, the invention should not be limited to the specific construction thereof, and is meant to be merely exemplary.
|
An axle driving apparatus consisting of a housing for compactly housing inner portions of axles, a hydrostatic transmission, and a transmitting mechanism for transmitting power to the axles from an output shaft of the hydrostatic transmission. The housing is partitioned by an internal wall into a chamber containing the hydrostatic transmission and a chamber containing the other transmitting mechanisms. The housing is filled with oil in common with both chambers. A trunnion for changing the output rotation of the hydrostatic transmission is disposed in parallel to the axles. A shock absorber is provided to prevent abrupt speed change. A differential locking device is attached to the differential gear to thereby improve the straightforward running capacity of the vehicle.
| 5
|
TECHNICAL FIELD
[0001] The present invention relates to a portable learning machine, more particularly, relates to a system and method for portable multimedia network learning machine (PMNLM) and remote information transmission thereof.
BACKGROUND OF THE INVENTION
[0002] Portable learning machines, such as PDA and portable e-dictionary, are more and more popular nowadays, especially for students. But the problem with the portable learning machines in the prior art are that all the learning functions, methods, and procedures are in built-in design during manufacture, even more, some of the learning contents are integrated. Therefore, the machines can not satisfy personal requirements of consumers; and even for those PMNLMs that are provided with updateable contents, the manufacturer will have to spend huge workloads to prepare courseware.
[0003] Although some of the portable learning machines in market are provided with the function of download learning contents from local computer or databases on remote servers via the Internet, but the operation is fussy and manual, the user has to download the contents one by one and independently, and automatic or intelligent download is not supported.
[0004] Moreover, the portable learning machines in the prior art provide simplex examination functions only, for the study status and progress, teachers, parents and student can not communicate with each other, and parents and teachers do not know how and what the students are studying. On the other hand, as students studied lots of knowledge, it is easy to disremember. Since there is no records, it will be very hard to track the knowledge, and when preparing the examination, the revision will become blindness and time-cost, for example, maybe some of the knowledge has been mastered but it is still being revised, and some knowledge has not been mastered but has not been revised.
[0005] The vocabulary mnemonics of the most portable electric learning machines normally applies Ebbinghaus Curve, that is, timely reminds the student to revise the learning content. But this mnemonics only focus on the vocabularies that already be recited, for the vocabularies do not be recited, there is no memory; moreover, for the vocabularies has already been recited by Ebbinghaus Curve, no memo exist any more, and the curve need be reset only if these vocabularies be recited again. With the metabolism of cerebra, the memorized knowledge will disremember gradually. Thus the mnemonics of the most learning machines are singleness and can not entirely simulate the knowledge that already be remembered, the content will forget along with the time lapse.
BRIEF SUMMARY OF THE INVENTION
[0006] The object of the present invention is to provide a PMNLM to solve the abovementioned problems in the prior art, and to provide a system and method for remote information transmission between such portable learning machines, as well as a method for preparing the multimedia files to be played by such portable learning machines.
[0007] The technical solution of the present invention is, providing a PMNLM, which comprising a micro-processor and a memory coupled thereon, an input device and a display, the memory is stored with a course schedule, a course hours file, a multimedia animation menu file and a multimedia courseware, wherein the PMNLM further comprising at least a communication and downloading module, a multimedia driver and a multimedia player, the communication and downloading module is for communicating with the computer that connected with the portable learning machine, uploading a teaching impression information file (the records and tracking of the studying status) via a “one key access” inspiring mechanism, downloading the multimedia animation menu file and multimedia courseware stored in a database of a remote server, and implementing the communication of information transferring and receiving between the PMNLMs, as well as inspiring the transmission of the teaching impression information file to a study-status receiving terminal; the multimedia driving device and multimedia player are for driving and playing the downloaded animation menu files and multimedia courseware.
[0008] Advantageously, the portable learning machine further comprises a memory point database unit which stored with memory point content, memory point index, and each memory point's skill level; a mnemonics module memorial unit comprising various mnemonics module programs for selecting by a main program P, each mnemonics corresponds to each memory point's skill level; an asst-study memory control unit controlled by the main program P to track the study status of the student, when one memory point is being studied and memorized, the main program P will intelligently select a suitable mnemonics module program according to the memory point's skill level of the student, meanwhile update this memory point's skill level and the corresponding date that the last time of contact with this memory point.
[0009] Advantageously, the input device is a keyboard which comprises catalog keys, English letter keys, vocabulary study keys to provide various ways for memorizing and revising, “one key access” key for downloading communication, network key for transferring files between two machines, Nmail key for editing mail.
[0010] The present invention further provides a system for transmitting remote information between the PMNLMs, which comprising a PMNLM, a PC, a remote server. Said PMNLM communicates with the PC via a download cable, the remote server communicated with the PC via internet, the system further comprises a study-status receiving terminal; the PMNLM comprises a memory unit for recording the study records and learning impression information files, and a communication transition unit for transmitting the information files to the PC automatically or by key-driven; the PC communicates with the remote server via internet, and the remote server comprises an intelligent analyzing module to analyze the received learning impression information files, and to determine a synchronous teaching materials, and then to generate a study-status result information; the study-status receiving terminal is associated with the PMNLM, and comprises an information receiving module for communicating with the remote server and receiving the study-status result information.
[0011] Advantageously, the database of the remote server is stored with the entire registered ID numbers of the PMNLMs, as well as the email information that did not received by the receiving terminal; these ID numbers and email information are used for ID verification of the PC communicated PMNLM, and for sending information to the PMNLM connected with PC for receiving information; the PC is installed with communication driver programs of automatically sending, receiving and downloading; the PMNLM is installed with a processing program, an email editing software and an email playing software in response to the instruction from the communication driver programs; the information transmission between the PMNLM and PC complies with the “one key access” communication protocol; and the information transmission between the remote server and PC complies with TCP/IP communication protocol.
[0012] Advantageously, the study-status receiving terminal comprises cell phone with short message function, desk phone or email receiving device, the study-status information from the remote server based on the user's subscription received by the terminal comprises attendance information, study trends information, homework analyzing, study details, examination ranking, parts or all of reviewing guidance; a short message sending module for sending the study-status information is provided between the remote server and the study-status receiving terminal.
[0013] Advantageously, a serial number is provided to associate the study-status receiving terminal, PMNLM, PC, synchronous teaching materials that download/upload from the server, and the teaching impression information file that send to the server; at least one part of the serial number is formed at the first time the PMNLM log onto the remote server, and each PMNLM forms an unique serial number at the first time log on.
[0014] The present invention further provides a method for implementing the information transmission between multiple PMNLMs, which is achieved inside a system with a PMNLM, a PC and a remote server, wherein the remote server stores the entire registered ID numbers of the PMNLMs, as well as the email information that was not received by the receiving terminal, intercommunication may be performed between the PMNLM and PC; the method comprises two steps of information sending and information receiving;
[0015] the steps of sending information further comprises the steps of: (a) setting the status of the information to be sent as “ready to send” on the PMNLM, and setting a serial number on the information receiving PMNLM; (b) connecting the PMNLM and PC, then perform automatically handshake authenticating thereof; (c) the communication driver program of the PC automatically inquires the PMNLM if there is any information need to be sent, the PMNLM then starts “NMAIL” management control to detect if there is any information need to be sent in the user's outbox, and then responds to the PC; (d) if there is information need to be sent, automatically uploads the information to the PC, and encrypts the information; (e) automatically connecting the remote server with the PC, and uploading the information need to be sent to the database of the remote server, then recording the ID serial number of the PMNLM which is sending and receiving the information; (f) deleting the mail that has already been sent from the “outbox”, or transferring to the “outbox”;
[0016] the step of information receiving further comprises the steps of: (h) connecting the PMNLM and the PC on the internet, and performing handshake; (i) acquiring the ID serial number of the PMNLM communicating with the PC by handshaking; (j) the PC automatically communicates with the database of the remote server, and searches whether any mail information that sending to the PMNLM with the corresponding ID serial number exists in the database; (k) if such information exists, downloading the information belongs to the PMNLM with the corresponding ID serial number to the PC; (l) the communication driver program of the PC then automatically decodes the information downloaded from the remote server and save to “inbox” of the user's PMNLM; (m) labeling the information as already sent in the database of the remote server.
[0017] Advantageously, a “one key access” key is defined on the input device of the PMNLM, when sending and receiving information, the two steps of information sending and receiving will be automatically achieved by simply press the “one key access” key for only once;
[0018] when enabled the “one key access” key, the PMNLM will further perform the following steps via the communication transmission unit: reading the new synchronous courseware on the remote server, and requesting to download the matched courseware base on the course time basic information, current time of the system, course schedule and running progress of a courseware correlation unit; uploading the user's teaching impression information file which comprising at least one of the times of the courseware be run, running recordation or study tracking; updating or amending the content of the courseware correlation unit to make it simultaneously reflect the using status of the current courseware; enabling the teaching impression information file to be sent to the receiving terminal.
[0019] The present invention further provides a method for preparing the multimedia file that can be played on the PMNLM. A communication and downloading module, a multimedia driven device, and a multimedia player are installed on the PMNLM, the multimedia file comprises animation menu file and multimedia courseware, wherein the method comprises the steps of: preparing a script file A1.ns or A1.txt in text format, and reading-in the script file as A1.txt in text format; format conversion, removing unnecessary spaces in the A1.txt and generating an A2.txt file, then opening this file and reading; decoding the instruction contained in the A2.txt on the corresponding position, generating an overall script file A3.txt; initializing the necessary environment variable of the multimedia file according to the certain instruction in the script; gathering all the files written in each area of the A3.txt, and generating relevant multimedia files base on the setting of the environment variable, these multimedia files comprises English courseware in *.nwe format, Chinese courseware in *.nwc format, examination courseware in *.nwx format, other multimedia files in *.nwf format, and nwf multimedia directory file that comply with animation menu file in .nmt format; downloading these multimedia files to the appointed catalog of the PMNLM through the communication and downloading module of the PMNLM.
[0020] Advantageously, the step of preparing a script file A1.ns or A1.txt in text format, and reading the script file as A1.txt by the text format further comprises the steps of: (a1) enabling the multimedia courseware creating tool NflashMX that based on Windows, and setting the machine type, internal file name and courseware information; (a2) editing the drawings and multimedia by the visible NflashMX multimedia object creation interface, or directly editing the relevant work script files; (a3) generating corresponding script file A1.ns.
[0021] Advantageously, the method further comprises the step of playing the courseware on the PMNLM: entering the courseware study interface, the PMNLM then listing all the current courseware files, and orientating the closest courseware according to the schedule preset by the user, as well as the course hour file and the current time of the system; loading the courseware player of the PMNLM once the user selected a certain courseware; detecting the validity of the courseware; initializing the courseware's instruction cache, instruction pointer and stack parameter; inquiring whether the instruction cache is empty; if it is empty, read the courseware instruction to the instruction cache via a file system; checking the validity and integrality of the courseware, and then load and run the courseware.
[0022] Advantageously, the method further comprises the step of playing the animation menu on the PMNLM: acquiring the animation menu data by the animation menu driver program according to the level of the menu, the serial number of the menu in the level, the animation menu comprises multimedia data pointer of the current animation menu; playing the current animation menu by the player according to the multimedia data pointer of the current animation menu, and this step comprises: loading the player that set on the PMNLM by the driver of the multimedia data pointer of the current animation menu driver program; detecting the validity of the courseware, and initializing the courseware's instruction cache, instruction pointer and stack parameter; reading the courseware instruction to the instruction cache; checking the validity and integrality of the courseware, and loading and running the courseware; the menu driver program estimating whether to enter a certain menu or exit the menu to enter the applying program and following the relevant operation, according to the return value of the current played animation menu.
[0023] Advantageously, the step of preparing the script file A1.ns or A1.txt in text format and reading-in the script file as A1.txt is achieved by a Nec.exe translation and editing tool.
[0024] Advantageously, the method further comprises the steps of combining groups of .nwf multimedia files which measure up with the animation menu criterion of portable terminal into a txt script file in text format, and creating a animation menu file in .nmt format by using the nmt.exe editing tool.
[0025] The advantages of the present invention are, the PMNLM is with simple configuration and it is easy to operate, especially the “one key access” configuration combining with the system and method for remote data transmission between the PMNLMs, makes the PMNLM easily transfer synchronous courseware and mails with the remote server. Further, the PMNLM makes the parents easily know the study status of their children. Moreover, the mnemonics provided in the present invention will evidently improve the memory impression of the user due to the application of different mnemonics on different user's skill level. Additionally, the method of preparing multimedia files as provided in the present invention makes the user create the courseware and animation menu files on the PMNLM, thus to increase the value of the PMNLM.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 shows one embodiment of the present invention of the system to realize the information transmission between PMNLMs;
[0027] FIG. 2 shows another embodiment of the present invention of the system to implement the information transmission between PMNLMs;
[0028] FIG. 3 shows the internal structure of the PMNLM of the present invention;
[0029] FIG. 4 shows the operation interface of the PMNLM of the present invention;
[0030] FIG. 5 shows the data configuration of the PMNLM of the present invention;
[0031] FIG. 6 shows the memory curve of the present invention;
[0032] FIG. 7 shows the operation flow of the main program P of the PMNLM of the present invention;
[0033] FIG. 8 shows the mail sending flow of the PMNLM of the present invention;
[0034] FIG. 9 shows the mail receiving flow of the PMNLM of the present invention;
[0035] FIG. 10 shows the multimedia script editing flow of the PMNLM of the present invention;
[0036] FIG. 11 shows the multimedia courseware downloading flow of the PMNLM of the present invention;
[0037] FIG. 12 shows the starting-up flow of the PMNLM of the present invention;
[0038] FIG. 13 shows the dictionary function implementing flow of the PMNLM of the present invention;
[0039] FIG. 14 shows the courseware playing flow of the PMNLM of the present invention;
[0040] FIG. 15 shows the examples of NflashMX for preparing multimedia courseware;
[0041] FIG. 16 shows the animation menu playing flow of the PMNLM of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0042] As shown in FIG. 1 , one embodiment of the present invention of the system to implement the information transmission between PMNLMs is provided. The system comprises a PMNLM 1 , a PC 2 connected with the PMNLM, a remote server 3 connected with the PC via internet, a cell phone short message sending module 4 connected with the remote server, a study-status receiving terminal 5 for receiving the information from the sending module. Each part of the system is described in detail hereafter.
[0043] The PMNLM 1 is similar with the downloadable electric dictionary or other downloadable terminal, the internal structure of which is shown in FIG. 3 , which comprises a microprocessor unit 300 , a first program memory 301 , a logic processing unit 302 , a second program memory 303 , a keyboard unit 304 , a data memory 305 , a static memory 306 , a communication transferring unit 308 , a voice processing unit 309 , a liquid crystal driver unit 310 , a LCD 311 and a power supply unit 312 , wherein the first program memory 301 , logic processing unit 302 and the second program memory 303 together form a program memory. A certain program is preset and run in the memory to connect with the PC 2 for controlling the download and selectively implementing the downloaded program.
[0044] The PMNLM 1 can transfer data with the remote server 3 via the PC 2 , and can download the synchronous teaching materials (synchronous studying contents) from the remote server 2 for exploring and studying, the synchronous studying contents comprising the divisions of vocabulary reciting, text studying, explain learning, exercising, examination, test exercising and Chinese Character studying, etc.; the synchronous teaching materials downloaded from the server at least comprises one of the following division: text, explain, exercise, exam, test paper, Chinese Character and recitation, the data recorded in each division at least comprises the implemented starting time and total time. The recordation of divisions further comprises error data, attendance information, study trends, homework analysis, details of the study, list of examination or review guidance, etc. During the synchronous study, the PMNLM will record the teaching impression information such as duration of study, stresses distribution, time distribution and errors occurred in examination, thus to generate a teaching impression information file (namely, study status recordation). The communication transferring unit 308 of the PMNLM will send the teaching impression information file to the PC automatically or driven by key. In the present invention, when the PMNLM is connected with the PC, the driver software of the PC will automatically acquire the user's teaching impression information file, and intelligently upload it to the remote server 3 . In one embodiment of the present invention, a key for transmission the teaching impression information file to the PC is set on the PMNLM; it is called as “one key access”. By enabling the “one key access”, the PMNLM will perform the following steps with its communication transferring unit:
[0045] reading the new synchronous courseware on the remote server, and inquiring download the matched courseware according to the course hour basic information, current time of the system, course schedule and running progress of a courseware correlation unit;
[0046] uploading the number of times the courseware ran, running recordation or study tracking;
[0047] updating or amending the content of the courseware correlation unit to make it synchronously reflecting the using condition of the current courseware;
[0048] sending the mail information to the remote server to update the data with the driver program of the PC;
[0049] sending and receiving mail information;
[0050] enabling the teaching impression information file, and then sending it to the receiving terminal.
[0051] The PC may comprise conventional PCs; it is equipped with a communication unit that suitable for communication with the PMNLM, it may apply common RS232 serial communication or USB communication, or infrared or Bluetooth protocol communication. An application program for communication (such as DLsprite) is installed on the PC. When the PMNLM of user is connected with the PC 2 , the PC 2 installed with corresponding applications will automatically acquire the teaching impression information file in the PMNLM 1 , and automatically sent the file to the database of the remote server and stored therein once the PC 2 is connected with internet.
[0052] An intelligent analyzing module is provided in the remote server 3 to analyze the teaching impression information file, and to gather the information of the user's synchronous download frequency, study time distribution and knowledge leak in a selected time period, thus to generate a study status analysis result or teaching impression information. Additionally, if there's no synchronous download for a long period, or no synchronous study happens and no study status recordation, a warning report of study status will be generated. The remote server 3 can send the teaching impression information by short message service, email or printing and mailing. For example, in one embodiment of the present invention, short message service is applied to send the study status analysis result. The remote server 3 having a short message sending platform with a short message sending module 4 , once the short message sending module 4 get the instruction from the remote server 3 , it will send the study status analysis result to the study status receiving terminal 5 (such as the appointed cell phone).
[0053] The study status receiving terminal 5 may comprise cell phone or fixed landline phone with short message function, or an email receiving device. The cell phone, fixed landline phone or an email receiving device may be appointed by the parents of the student, and the study status analysis report can be subscribed, such as subscribe the classified content of the analysis report, the receiving manner (for example, telephone number or email address) and the appointed receiver. The detail of the study status analysis report comprises parts or all of work attendance information, study trends, homework analysis, study status, exam list and review guidance.
[0054] A serial number is provided to associate the study-status receiving terminal with the PMNLM, at least one part of the serial number is determined at the first time the PMNLM logs on the remote server, and each PMNLM generates a unique serial number at the first time logs on. The automatically downloaded synchronous teaching materials from the remote server to the PMNLM is compressed and encrypted, and once it is received, it will be decoded automatically, and the password for decoding is associated with the ID serial number of the PMNLM. As the user requires “synchronously” study, the synchronous teaching materials need to be downloaded frequently, so the remote server will accumulate the user's study recordation, and the intelligent analysis module will get the analyzing result momentarily.
[0055] FIG. 2 shows another embodiment of the present invention, in this embodiment, the PMNLM may transfer (sending or receiving) mails between the PC and the remote server.
[0056] As shown in FIG. 4 , the operation interface of the PMNLM of the present invention is provided. The operation interface comprises an LCD on the upper side, an operation keyboard and a phonation device on the lower side. The keyboard is installed and fixed on the upper surface of the shell of the PMNLM, and a cover is set thereon; the LCD is set on the inner surface of the cover, the shell and the cover is engaged on the backside in loose-leaf manner, or overlap together in push-and-pull manner, or rotatively engaged; an I/O interface for connecting peripheral equipment is set on the side face of the shell. The keyboard comprises English letter keys, NCELL vocabulary reciting keys, input method selection key, “one key access” function key, Internet key, numbers keys, orientation keys and user-defined functional keys. Wherein the English letter keys are for inputting English words and sentences; the NCELL vocabulary reciting keys are for enabling the system entering the status of vocabulary reciting, tracking the contents of the student is memorizing, and intelligently providing various mnemonics; the “one key access” function key is for synchronously downloading the user's study courseware, uploading the teaching impression files, sending and receiving mails information, inspiring study-status reporting mechanism; the Internet key is for downloading information from the PMNLM connected with PC or inter-transferring files between PMNLMs; the input method selection key is for switching the inputting manners of English character input, Chinese character input and manuscript character input; the numbers key are for counting or inputting mathematics formulae or inputting accessorial selections; the orientation keys are for moving cursor; the user-defined functional keys are for defining some regular functions by the user itself.
[0057] The PMNLM of the present invention further provides the function of NCELL memory snapshot. The micro-processor of the PMNLM is controlled by the main program P, the memory is stored with the main program P, database of studying materials and the skill levels thereof, and memory point database unit, mnemonics module storage unit and asst-memorizing control unit. The main program P will select and implement different mnemonics programs according to the user's skill level on certain memory points. And the memory point database unit is stored with memory point contents, memory point index and skill levels for each memory point; the mnemonics module memorial unit with various mnemonics module programs is for selecting by a main program P, each mnemonics corresponds to each memory point's skill level; the asst-study memory control unit is controlled by the main program P to track the study status of the student, when one memory point is being studied and memorized, the main program P will intelligently select a suitable mnemonics module program according to the memory point's skill level of the student.
[0058] The memory point content comprises English vocabulary, English sentence, English grammar, formulas for mathematics, physics and chemistry, Chinese Tangsong Poetics, Chinese text, Astronomy and Geography, download materials, and other subjects, also, certain affair can be deemed as a memory point.
[0059] All the memory points are numbered, and each memory point is set with a skill level, when the user accessing a certain memory point, the skill level of this memory point will increase, and the corresponding date will be recorded. As time lapsing, the skill level for the vocabularies will attenuate; as the skill level of one vocabulary attenuated to a critical level, it will be listed in a memory or memory enhancement program.
[0060] The memory or memory enhancement program is a remembrance process that at the assistant of hardware and software, this process will apply different mnemonics according to the skill level of a certain memory point.
[0061] FIG. 5 shows the data configuration of the PMNLM of the present invention, this database comprises memory point content, memory point index and skill level data area. The system software will search the address of skill level data in accordance with the memory point content, then process the data at the skill level data area. The “Ni” in FIG. 5 means the index list of the memory point, it has two parts: memory, the skill level address of the memory; “Nc” means the memory data of the memory point, it also has two parts: the skill level changed at the last time ND and the last time that accessed the vocabulary NT; ND occupied 4 bit and may indicate 16 levels of skill level; NT occupied 12 bits and may record 12 years time period, so all the courses from grade school to senior high school of a student could be recorded therein.
[0062] The different mnemonics comprises transcribing, selection, filling in blank, writing, exploring and game. The intelligent memory means selecting different mnemonics according to different skill level of memory point, if the skill level is low, the system will select simpler mnemonics such as transcribing and selection; if the skill level is high, the system will select mnemonics such as exploring and game, the relevant knowledge just pass through the user's cerebrum and do not need to waste time in revising. Once the memory program of a memory point is finished, the skill level will reach maximum value; this memory point will then remain in the user's cerebrum for a long time. The matching of each study condition and each kind of mnemonics is shown as follows:
Skill Level Strangeness Mnemonics Screen Displaying 0-2 unacquainted Transcribing Display vocabulary and its explanation; The User input the spelling of the vocabulary, if matched, this level is passed. 3-5 Unknown selection Displaying one meaning of a vocabulary and plentiful vocabulary of vocabulary entries; The user needs to select one correct vocabulary entry. 6-10 Skilled Filling in Giving the Chinese explanation of an English blank vocabulary, stochastic parts of the vocabulary is in blank; The user needs to fill in blank with correct letter. Writing Giving the vocabulary entry; The user needs to write out the explanation of the vocabulary. 11-15 Saturated Exploring Just exploring the vocabulary; Set options: auto explore/manual explore (the explore speed can be set); acceptation recollection/vocabulary recollection (acceptation/vocabulary will recollect separately); capitalization of the vocabulary. Game Such as associating, bumblepuppy, forting, star wars.
[0063] Continually revising the studied content will increase its skill level. Therefore, a new content requires a scientific mnemonics, this scientific mnemonics will timely remind the user to review the content till the skill level is saturated, and the remembrance of the knowledge will last for long time. As shown in FIG. 6 , the change of skill levels is provided after the second day reminder, the third day reminder, the fifth day reminder, the eighth day reminder, the tenth day reminder, the eleventh day reminder.
[0064] As time lapsing, something in the cerebrum will fade, and the skill level of each memory point will decrease. For those which remembered profoundly, the time period for fading is long, and for those which remembered superficially, the time period for fading is short. The skill level of a memory point will decrease with time lapsing, as shown below:
Fading Speed Skill Level unacquaintedness (days for decreasing one level) 0-5 unacquainted 7 6-10 Skilled 15 11-15 Saturated 30
[0065] Improvement of skill level: everything will create a memory when it reached to the cerebrum, if this memory appears again, it will enhance the skill level. The PMNLM can help the user to improve the skill level according to the time and number of times of memorization. The increasing and decreasing of the skill level is a contrary process, which means low skill level needs constantly revision to improve the skill level by transcribing, filling in blank, writing and reading.
Increasing Speed Memorizing Manner (the level increased) Transcribing 2 Selection 2 Filling in Blank 3 Writing 3 Exploring 1 Game 1
[0066] The PMNLM of the present invention factually simulated the memory process of human's cerebrum, it is be called as memory snapshot (NCELL) system. As metabolism of the cerebrum, the memorized content will forget gently, the system of the present then simulate this forgetting process with time lapsing, dynamic track the user's mastering of the memory point, and remind the user to review the memory point.
[0067] FIG. 7 shows the operation flow of the main program P of the PMNLM of the present invention. For the first time the student uses this method, he/she may have forgotten some contents, thus the skill level of the memory point need to be initialized and preset, and then the memory system will track contents which the user is memorizing, if a new memory point is memorized, it will be put into a historical memory stack; if a memory point is accessed, the skill level of this point will be increased and the current time will be recorded also, and then return to A. When reciting a memory point, read out the last skill level and last access time, and calculate the skill level of the memory point at the current time; then intelligently select different mnemonics according to the skill level, namely, intelligent memory; and then increase the skill level of this memory point, update the last contact time of the skill level; and finally, estimate whether this memory point is saturated, if that, return to A, if not, then apply the scientific mnemonics of FIG. 5 , and timely remind the user to revise till the skill level of this memory point reaches saturation, then return to A. The skill level of the memory point will decrease with time lapsing, once it decreases to a certain level, a preset program in the micro-processor will automatically set this memory stack as memory enhancement program, and re-enter the scientific mnemonics of FIG. 5 .
[0068] Then return to FIG. 2 , another embodiment of the present invention of the system to implement the mail transmission between PMNLMs is provided; the information transmission between PMNLMs is called as “NMAIL” to differ with the well-known “EMAIL”. The PC is provided with auto sending, auto receiving, and auto downloading one-off achieving communication driver program in respond to the “one key access” key; the PMNLM is equipped with a processing program for responding and implementing the communication driver program; the PMNLM, PC and the remote server comply with the “one key access” communication protocol; the PC and remote server comply with TCP/IP communication protocol. The “one key access” communication protocol applies simplex-duplex to implement real-time transmission of the data. The communication protocol supports the basic functions of data upload and download, catalog build and delete, data inter-transfer between two PMNLMs or between PMNLM and PC, two PMNLM interconnected gaming, NMail sending and receiving, one key access, etc.
[0069] The database of the remote server is stored with the entire registered ID numbers of the PMNLMs, as well as the email information that was not received by the receiving terminal. A mail editing software is installed in the memory of the PMNLM, and a NEPLAYER software for playing the multimedia mail is also installed therein; the mail editing software can be utilized as an editing platform for the multimedia mail, and the mail also can be set as auto play, start-up menu, timely remind, festival remind or count down. The PC and the PMNLM may inter-communicate with each other, and before that, the PC and the PMNLM need a handshake procedure, which comprises:
a. handshake detection to verify the communication speed, both of the PMNLM and the PC plight a basic baud rate, the monitoring port of PC waits for response from the PMNLM, the PMNLM sends out certain character string “HSK_STR” as a response, if there is an error response, the handshake will fail; b. Enabling mode and version detecting, once the handshake is passed, PC will feedback an ACK, the PMNLM will send Comm_Mode to notify whether the enabling mode is auto sending, auto receiving, and auto downloading one-off achieving “one key access” mode, or user manual selecting menu uploading and downloading mode; if the enabling mode is not ratify by the PC, it will not pass the detecting; c. Machine model ID verification, the PC needs to know the ID of the connected PMNLM, thus to communicate with the remote server, once the ID is verified, the PC will adjust its port's baud rate to match with the communication speed of the PMNLM, and preparing for subsequent communication; the PMNLM will then enter standby mode.
[0073] The communication processes between the PC and the PMNLM after said handshake include the PMNLM downloading and uploading files through menu access. Each user of the PMNLM has a unique personal ID (PID) to distinguish with each other.
[0074] In the transmission of NMAIL, a PID address and the start up mode of the receiving end are attached therein. The remote server will build a relevant NMAIL database on the receiving end according to the PIN address of the NMAIL, and keep the NMAIL into the “send-box” of the database, then wait for communication with the receiving end. If the PMNLM on the receiving end is online, then the NMAIL will be sent to the relevant personal processor controller of the receiving end via the driver program of the PC, and then through the personal processor controller to download the NMAIL to the PMNLM via a download line (such as USB, UART or wireless communication).
[0075] The PMNLM saves the received NMAIL to “in-box”, and meanwhile builds the received startup mode into a NMAIL startup bookmark.
[0076] For the management of NMAIL, each NMAIL is built with a relevant NMAIL label bookmark to mark the status of the NMAIL, such as whether to be started up, whether to be forwarded, whether to be deleted, and also, the label bookmark comprises the sender's PID address, receiver's PID address and the receiver's startup mode.
[0077] Patterns of the startup bookmark are as follow:
Title of the NMAIL Startup Time Startup Mode
[0078] Patterns of the label bookmark are as follow:
Title of the Send PID Receive PID Status of the Startup Mode NMAIL NMAIL
[0079] There are three ways for transmission:
1. “one key access” communication, in this way, no manual process is required, similar to PCs, once the PMNLM is linked with internet, and press the “one key access” key, it will automatically send and receive all NMAIL files. 2. Internet transmission via PC, in this way, it requires entering relevant menu manually, it will be a little more troublesome. 3. dual machine inter-communicate, two or more users may apply this method to inter-communicate with each other, and to directly transfer files by menu processing.
[0083] In the present embodiment, the media for transmission comprises Internet, transferring programs, USB, UART, infrared ray, wireless, PDA, servers or PCs.
[0084] The content of the NMAIL may comprises debonair remind, study persuading, encouraging, study status report, festival remind, birthday blessing, and other information such as FLASH, greeting or well-wishing.
[0085] The startup methods comprises boot-strap, festival remind, count down or timely remind, etc.
[0086] FIG. 8 shows the mail sending flow of the PMNLM of the present invention, wherein comprise the steps of:
[0087] the user edit the Nmail that needs be sent on the PMNLM or PC, and saves it in the send-box, then set startup mode and preset receiving terminal;
[0088] after the PMNLM is connected with the PC via the internet, then continue the following three steps for of handshake: 1) the PC monitoring and receiving the communication speed that required by the PMNLM; 2) the PMNLM sending the enabling mode as “one key access” mode or manual downloading mode; 3) the PC verifying the ID and communicate speed of the PMNLM, and sequentially communicating with the PMNLM at the required speed;
[0089] the PC logging on to the remote server via a data transmission program (DLSprite, for example), and asking for verifying ID and communicate speed; then verifying the ID, speed and updated personal information of the send end by the remote server;
[0090] the PC transmission program automatically inquiring whether the PMNLM terminal has any Nmail to be sent; the PMNLM will then be receiving the inquiring and starting management control of the ExplorerNmail to search whether any Nmail to be sent exist in the send-box of the Nmail directory path;
[0091] the PMNLM then responding with the transmission program of the PC, and feeding back there is an Nmail to be send; then automatically uploading the Nmail of the PMNLM to the PC and start encrypting;
[0092] the PC then automatically upload the Nmail from the send-box of the PMNLM to the remote server by the transmission program; the PMNLM then deleting the sent Nmail in the send-box, and forwarding the sent Nmail to the sent-box; the remote server the storing the received mail into the relevant database that preset by the receiver;
[0093] repeating the above described processes till the send-box of the PMNLM is empty; the sending process is then finished.
[0094] FIG. 9 shows the mail receiving flow of the PMNLM of the present invention, wherein comprises the steps of:
[0095] after the PMNLM is connected with the PC on the internet, then continue the following three steps for handshaking: 1) the PC monitoring and receiving the communication speed that required by the PMNLM; 2) the PMNLM sending the enabling mode as “one key access” mode or manual downloading mode; 3) the PC verifying the ID and communication speed of the PMNLM, and starting communication driver program, automatically detecting the user's ID serial number of the PMNLM;
[0096] the PC logging on to the remote server via a data transmission program (DLSprite, for example), and asking for verifying ID and communication speed;
[0097] the remote server then verifying the ID, speed and updated personal information of the portable device;
[0098] the PC then starting the communication program, automatically inquiring whether the PMNLM has any information to be sent; the PMNLM then starting “NMAIL” management controller to detect whether there is any mail to be sent in the send-box, and responding to the PC;
[0099] the PC then automatically communicating with the database of the remote server to search whether there is any Nmail to be sent to the PMNLM, if there is, the remote server will send the Nmail to the connected PC, and the server will be deleting the Nmail at the same time; the PC then decoding and downloading the Nmail and its startup mode to the in-box of the connected PMNLM;
[0100] the PC then deleting the NMAIL from its send-box, and mark the status as already been sent in the database of the remote server;
[0101] repeating the processes described above till the send-box of the database that corresponding to the receiving user's server is empty; the receiving process is then finished.
[0102] The present invention further comprises the step of preparing courseware and animation menu that playable by the PMNLM.
[0103] As shown in FIG. 10 , the multimedia script editing flow of the PMNLM of the present invention is provided; this process usually is implemented on a computer, and also can be implemented on a PMNLM with at least 8 bit of MCU.
[0104] In the present embodiment, the format of the courseware comprises: multimedia files in .nwf format, explorable or amendable text script files in .txt format, explorable or amendable text script files in .ns format, explorable or amendable text work files in .npr format, English courseware in .nwe file, Chinese courseware in .nwc format, and examination courseware in .nwx format.
[0105] The language for preparing courseware mostly is Nflash language, but this language is developed focus on portable system especially for 8 bit MCU. Another NEP language is developed focus on study; it comprises, summarizes and encapsulates the actual common study behaviors into instructions. The present invention is just applying NEP and Nflash instructions to prepare lively, rich and colorful courseware.
[0106] In the present invention, the NEP instructions comprise: 3 items of control instructions (TrueEcho, FalseEcho, TrueExplain), 6 items of vocabulary reciting instructions (StudyWords, PokeWords, GalxysWords, QlookWords, LinkWords, ListenWords), 3 items of text instructions (TextPlay, TextRead, etc.), 8 items of exam instructions (ExamAtart, ExamEnd, ExamFillBlank, ExamChoice, ExamMulChoice, ExamTrueFalse, ExamListen, ExamReading), 5 items of Examining instructions (ExamDIY, ExamDIYEND, DISCRIBE, ITEM, TOPIC), and 1 item of Chinese Character study instruction (ChineseFont).
[0107] And the Nflash instructions comprise 11 items of fake instructions, 3 items of voice instructions, 13 items of drawing instructions, 3 items of figure instructions, 3 items of screen instructions, 3 items of text instructions, and 11 items of control instructions.
[0108] In the present invention, editing tool NEC.exe is applied to prepare multimedia files in new/nwc/nwx/nwf format, in step 401 ( FIG. 10 ), preparing script file A1.txt in text format, and read-in this script file as A1.txt in text format; if error occurred in reading the file, then information of reading error will be reminded, if reading regularly, then initializing the system constant table and all the instruction's format template, and then searching all the Include instruction in the A2.txt, and analyzing its vocabulary and grammar; after that, estimating whether this analysis is correct, if incorrect, reminding an error, and if correct, proceed to step 403 and decoding all the instructions contained in the Include to the relevant positions, and creating the whole script files A3.txt; wherein, once A3.txt is created, each instruction code need be detected one by one, comprises analysis of vocabulary and grammar, if incorrect, displaying error reminding information; if correct, then detecting the specific instructions that must appeared when writing the script file through out the A3.txt; if incorrect, displaying error reminding information; if correct, detecting whether the positions of the appeared specific instructions are correct again, if incorrect, displaying error reminding information; if correct, going to step 404 ; and initializing the necessary environment variable with the specific instructions in the script; wherein comprises the processes of writing all the A3.txt instruction contents into the area division result file (parts of fake instructions do not create instruction code, only for setting), and labeling some of them, and re-writing index address. After that, in step 405 , gathering all the area division result files, creating *.nwe, *.nwc, *.nwx or *.nwf files according to the setting of environment variable; at last, going to step 406 , deleting all the interim files that occurred, such as A2.txt, A3.txt. Therefore, the multimedia courseware is created. The courseware then be downloaded to the appointed catalogue of the PMNLM via the communication and downloading module of the PMNLM.
[0109] The courseware is creased by the Nec.exe tool, it needs manually write out the A1.txt script file at first, and then edit the required courseware with Nec.exe.
[0110] In another embodiment of the present invention, a visible multimedia courseware creating tool can be applied to create the multimedia file (courseware). The visible multimedia courseware creating tool is NflashMX based on Windows, it describes the created courseware by screen operation, drawings, figures, voices, letters; so in the step 401 mentioned above, the user does not need to write TXT script file, just needs to create the multimedia object by the NflashMX visible tool and modifies it (at the same time, NflashMX will create relevant object's script instruction), the user can then edit the multimedia objects and grammar objects of the NFlashMX via the visible multimedia object creation interface. These objects are the basis for creating NFlash instruction script. When the user is saving the files, the present project will be packaged into a work file packet, and create two files that similar with text format file: a *.npr work file and a *.ns script file (these two files can be opened by notepad program); and when opening files, the selected project file packet will then be opened. The system will be editing the current created NFlash instruction script at first, then creating the result file in accordance with the NFlash instruction script.
[0111] Referring to FIG. 15 to describe the operation processes of NFlashMX. In one embodiment, user can edit instruction, edit script, emulating and managing courseware visibly by using NFlashMX. Once opened the NFlashMX, three lines default Chinese code will appear on the code column of the visible multimedia object creation interface, namely, 1. set machine type (such as NP3168); 2. set internal file name (such as “my courseware”); 3. set courseware information (such as “multimedia entertainment”, “synchronous study”, “simulate examination”). These three lines of codes are indispensable in any courseware, the user set the machine type at first, then make necessary amendment on the internal file name; the third line of the codes determines the type of the multimedia created; if select multimedia entertainment, then create NWF multimedia file; if select synchronous study in the relevant “courseware set information” column, it needs to set other information in the column, such as publisher, teaching material, grade, term and subject; the selected subject determines the type of the created courseware, if English is selected, it will create NEW English courseware, if Chinese is selected, it will create NWC Chinese courseware, other courseware is in NWF file (similarly, if “simulative exam” in the “courseware information” column is selected, it also needs to set other information in the column, such as publisher, teaching material, grade, term and subject; the selected subject determine the type of the created courseware, if English is selected, it will create NEW English courseware, if Chinese is selected, it will create NWC Chinese courseware, other courseware is in NWF file); then open the notepad program by the “view work script” order of the “tool” column in NFlashMX menu, a .ns script file in text format same as to .txt file will appear, in this script file, there is three lines of codes corresponding to the Chinese user's instruction: “NPset NP3168 (the appointed machine type is NP3168 herein), SetNFlashName and MCCdef Null” mentioned above; of course, all the scripts of the instructions can be viewed with this operation. Afterward, the user can insert and amend certain multimedia object by using the visible multimedia object creation interface, such as, once the user select “instruction options card/drawings”, a “draw beeline/draw rectangle/draw circle” instruction will appear on the below; if the user click “draw circle” instruction, in the “design panel” column of the screen will appear a circle with default size, and on the left side of the screen will display relevant parameters such as abscissa of the centre of a circle, Y-coordinate of the centre of a circle, radius of the circle, color of the paintbrush, linetype, linewidth and filling-in mode, the user amend the relevant parameters of necessary and click “insert”, this insertion will be enabled; and the column of code design will display user's instruction of this process in Chinese, if open the “tool/view work script” menu at the NFlashMX operation interface, one can see that the effective edit code of this operation instruction has been stored in the .ns script; then the user can follow next insertion process; further, the user can amend the drawing at any time he wants, likely, the user can control the edition effect by inputting drawings, voices, words, screen via the NflashMX. Once all the visible operations are finished, the script of the multimedia is created, then, only need to click “tool/view work script” order, the notepad program will open and the .ns script file in text format same as to .txt file is appeared. Then click the “edit” button of the NFlashMX multimedia object creation interface, the NFlashMX will start Nec.exe edition program, the “debugging” column on the screen will display the editing on the script is successful, and point out the saving path of the created multimedia file. In one embodiment of the present invention, if a saving operation has already been executed on the *.npr text format work file that can be opened by notebook program before edition, then the path of the multimedia is located in the same catalogue as to the *.npr work file; the files saved in the directory file further include the notebook program openable *.ns script file that created at the time of saving *.npr work file, and this *.ns script file is A1.ns in default. Of course, during editing, at any time if click “saving” button in the tool column, two text files that can be opened or amended by notepad program will be created and saved: work file with *.npr suffix, script file with *.ns suffix; the *.npr work file and the *.ns script file can be opened or amended by notepad program, and the effect of amendment is similar to the visible multimedia object editing that directly edited on the NFlashMX multimedia object creation interface. And further, the *.ns script file equals to the foresaid A1.txt text format script file. If the user needs to edit this project and script files to create relevant multimedia courseware files, just click the “edit” button of the NFlashMX multimedia object creation interface, the NFlashMX will start Nec.exe editing program, then the multimedia files in NWF/NEW/NWC formats will be created according to the user's set course subjects in the “courseware information”. By using this method of editing NFlashMX multimedia object and grammar object via visible multimedia object creation interface to create script file, it is more user friendly and easier to operate, and the user needs not to remember all complex instructions and rules. On the other hand, the user can also use the emulate tool of NFlashMX to imitate the created courseware on the PC, and needs not to test it on the PMNLM.
[0112] If the .nwf multimedia menu files created in accordance with the processes mentioned above satisfy with the animation menu criterion of the PMNLM, then the animation menu files in *.nmt format will be created. Normally, a plentiful group of nwf multimedia files that satisfy with the animation menu criterion of PMNLM are combined by a certain rule to create a txt script file in text format, and create the animation menu file in .nmt format by using nmt.exe edition tool, and editing and writing the nwf files into relevant Aa.txt script files in text format, and the number of the nwf files is determined by the level of the menu and all the number of the menus under all levels; opening the input Aa.txt script with nmt.exe edition tool; testing whether the grammar of a single sentence is correct; read-in all the instructions to the memory; comprehensively testing the correctness of the instruction combination and estimating whether all the related files can be read normally; comprehensively write the instructions in Aa.txt into *.nmt to create nmt animation menu files.
[0113] Once the groups of nwf multimedia files mentioned above that satisfy the animation menu criterion of PMNLM are combined by a certain rule to create a txt script file in text format, using nmt.exe editing tool to create animation menu files in .nmt format, wherein the certain rule means:
[0114] 1. NMTset NMTseries (for setting “applicable machine type” in the preamble of a nmt file, and filling in “edition number”):
Field Explain NMTset Instruction for setting machine type NMTseries Machine type
[0115] 2. NMTname name (for setting internal name of .nmt file):
Field Explain NMTname Instruction for setting internal name name Internal file's name
[0116] 3. Menuitem level menu_NO. filename (for setting each nwf menu file's property, the filename must be a .nwf suffixed file):
Field Explain Menuitem Instruction for setting nwf file's property level The level of the menu menu_NO. The serial number of the menu in this level filename nwf file's name relevant to the menu
[0117] FIG. 11 shows the download flow of the PMNLM of the present invention. If the courseware is prepared by the PMNLM, this flow can be elided. The flow starts from step 50 , the user inputting and saving the title of grade, term and teaching materials to be studied inside the PMNLM. In step 51 , setting course schedule according to teaching arrangement, labeling the course time arrangement and effective study time, the effective study time means the time period from the beginning of term to final exam. Then goes to step 52 , presetting the downloading content for each time, such as, the user can set one course or one course unit for each time the user downloads, and can appoint the content by itself. Once the preset is completed, proceed to step 53 and 54 one by one, connecting the PMNLM with the PC via a data cable and starting up the “one key access” system of the PMNLM, the PC will automatically be acquiring user's information and course schedule arrangement information; wherein the PC may automatically connect to the “one key access” remote database server 30 at the time of starting up, or driving and connecting to the “one key access” remote database server 30 after step 54 . And in step 55 , the PC transferring the user's information and the synchronous courseware information to the remote database server to register and request for downloading, if the remote database server found out that the user is unregistered, then proceed to step 57 , reminding registering the PMNLM, and once registered, assigning the PMNLM an unique PID as identity label, and based on the information of grade, term, teaching materials and server saved outlines set by the user to download the relevant courseware files to the PMNLM; and if the user is already registered, the PMNLM will calculated the starting point of the present courseware according to the courseware file, course schedule and current system time, and transferring this information to the remote database server via the PC to determine the start point of downloading (step 58 ); the remote database server execute step 580 , namely, the PC inquiring the PMNLM whether there is courseware that equal to the content to be downloaded existing, if exists, proceed to step 59 and will not download this courseware; if not, proceed to step 590 , and downloading the courseware to the PMNLM via the PC. Thus, the whole step of setting and downloading the courseware is finished.
[0118] It is understood that in the system and method for downloading and playing multimedia files by the PMNLM of the present invention, the courseware files comprises Flash files, specific files, drawings, MIDI music and voices; wherein the courseware comprises the processes of vocabulary reciting, testing, text studying, paper examining, Chinese character studying, etc.; and the vocabulary reciting comprises transcribing, filling in blank, linking, dictating and words gaming; the testing comprises dictating, filling in blank, multi-filling, selecting and true/false; the feeding back interface can be various based on different testing results, and makes the interface dramatic and liveliness, and provides teaching and studying with more fun.
[0119] After download, if the user needs to open the courseware, there are two ways to find it: 1) pressing the relevant functional button of the PMNLM (for example, if the user wants study .nwe English courseware, there is a shortcut button for English study on the PMNLM), entering into the relevant studying interface, the courseware player will be automatically locating the current courseware to be studied and will be displaying it reversely, then selecting other courseware by up/down direction keys, and startup the playing process once the user confirmed the courseware; 2) opening the courseware schedule of the PMNLM, and pressing the page up/down buttons to select the courseware on the schedule, the PMNLM will be automatically searching then, and once the user confirmed and pressed the “enter” button, the PMNLM will startup the player, and the user can then study the downloaded content.
[0120] FIG. 12 shows the starting-up flow of the PMNLM of the present invention. Step 60 is starting up the machine by pressing the power ON/OFF button of the PMNLM; in step 61 , if the auto on/off function be set, the machine will be automatically started up at the preset time, and executing step 63 to enter main directory interface; if no auto on/off be set, then executing step 62 , the user turning on/off the machine manually and entering into the main directory interface; then proceed to step 64 , the PMNLM will querying if there is any key pressing inputs, if there is, proceed to step 65 , entering the relevant function according to the user's input; if there is not, proceed to step 66 , turn off the machine after a certain time period, and the certain time period is preset by the user.
[0121] FIG. 13 shows the dictionary function implementing flow of the PMNLM of the present invention. In step 70 , the user starting up dictionary function, then inputting the vocabularies to be searched as in step 71 , the terminal device then implementing step 72 to match and display the vocabularies; the user can apply wildcard such as “?” or “*” for intangibly searches; after that, displaying the searched items and proceed to step 73 , the user then may explore the explanation of them on the displayer 102 ; moreover, the user can further conduct the following steps: step 74 : turning up/down to view the explanation of the vocabularies and their property; step 75 : reverse searching or skip searching the explanation; step 76 : glossary notepad operation; step 77 : words vocalization operation.
[0122] FIG. 14 shows the courseware playing flow of the PMNLM of the present invention. The machine is started up in step 80 , and automatically entering the courseware study function, or switched to this functional by the user; in step 81 , the system of the PMNLM will be listing all the courseware; in step 82 , the system locating the most recent courseware according to the course schedule, course time file and system time set by the user; in step 83 , after the user verifying, the system then loading the courseware player; in step 84 , the player detecting validity of the courseware file; in step 85 , initializing courseware instruction cache memory, instruction pointer, stack parameter; in step 86 , inquiring whether the instruction cache memory is in blank; if not, in step 87 , reading-in the courseware instruction to the instruction cache memory via file system; in step 88 , checking the validity, integrality of the courseware instruction, then loading and running; in step 89 , if the instruction of closing is received, then exiting the system; in step 90 , if the instruction of background is received, then set as background state and starting-up and running; in step 91 , if get the instruction of studying, then recording the result data of instruction running as well as the progress data (comprises study result recordation, achievement recordation, study progress recordation and time recordation); in step 92 , checking the user's operation of Fast Forward/Fast Reverse/Pause/Exit/Volume; at last, backs to step 96 .
[0123] FIG. 16 shows the animation menu playing flow of the PMNLM of the present invention. At first in step 90 , acquiring the animation menu data by the animation menu driver program according to the level of the menu, the serial number of the menu in the level, the animation menu comprises multimedia data pointer of the current animation menu. In the present embodiment, the system is default as root directory at the time of starting up.
[0124] Then in step 91 , playing the current animation menu by Neplyer according to the multimedia data pointer of the current animation menu, namely, the current menu can be played in multimedia form; and include the steps of: loading the player that set on the PMNLM by the driven of the multimedia data pointer of the current animation menu driver program; detecting the validity of the courseware, and initializing the courseware's instruction cache, instruction pointer and stack parameter; reading the courseware instruction to the instruction cache; checking the validity and integrality of the courseware, and loading and running the courseware.
[0125] And then in step 92 , acquiring the returncode of the current animation menu, and estimating whether this returncode is entering into the upper menu (step S 43 ). For example, in one embodiment of the present invention, the rule for estimating is, if the returncode is “PREDIR”, that means back to the upper menu.
[0126] In step 93 , if the returncode indicates returning back to the upper menu, then back to step 90 ; if it did not enter into the upper menu, then estimating whether entry into the lower menu in step 94 , if the returncode is “NEXTx” (wherein “x” refers to a number, means the serial of .nwf file in the lower menu), that means go to the lower menu; and when entered into the lower menu, then backs to step 90 ; if it did not enter the lower menu, then proceed to step S 45 .
[0127] In step 95 , if the returncode is a functional identifier, then skipping out the animation menu and entering into the relevant functional interface to execute the functional application program.
[0128] When exiting the application program, then returns to step 90 .
|
A kind of portable multimedia network learning machine, includes a microprocessor and a memory connected to the microprocessor, input unit and display, communication and download module, multimedia driving device and multimedia player. The said communication and download module are used for communicating with the calculator connected to the hand-held multimedia network learning machine, uploading effectiveness of instruction message file, and may download multimedia cartoon menu file and multimedia packages in step with teaching in the far end database server, transmit learning situation result to the learning situation receiving terminal. While multimedia driving device and multimedia player are used for driving and playing the said downloaded cartoon menu file and courseware. The present invention also provides a kind of system and method realizing remote information transition between hand-held multimedia network learning machines. The present invention also provides a kind of method for producing multimedia document which can be played in the hand-held multimedia network learning machine. The present invention could expediently produce multimedia document or swap data with remote server.
| 6
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority under 35 U.S.C. §119 of U.S. Patent Application 60/721,321 filed 27 Sep. 2005, the disclosure of which is expressly incorporated by reference herein in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A COMPACT DISK APPENDIX
[0003] Not applicable.
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The invention relates to through air dryer (TAD) fabrics, and more particularly, to TAD fabrics have a composite whereby side fabric portions are woven to the main body portion of the fabric.
[0006] 2. Background of the Invention
[0007] There is continuing need to improve the fabrics used in TAD applications. For typical dryers such as non-TAD, there is a need to alternate standard and, for example, PPS yarns, to prevent tension variation during the heat-setting process. Still further, PPC is used in some fabrics across the entire width of the fabric, and this is very expensive. PPS does not have the same level of tenacity as PET, so a combination is better.
[0008] In many TAD machines, the paper that is produced is trimmed at the forming section prior to being transferred to the TAD fabric. At the TAD section, as depicted in FIG. 1 , hot air is blown going through the paper 100 and passing through the fabric 102 and drum 104 . However, as the paper was previously trimmed, there is an area of the fabric 106 that received more air flow at higher temperatures.
[0009] The result is that the fabric that is not in contact or otherwise protected by the paper web is exposed to the harsher paper machine running conditions than if the fabric was protected by the web. This result in premature wear or other destruction of the fabric.
[0010] Accordingly, a need exists for a TAD fabric having the ability to survive under the harsh environments longer by postponing the wear at the exposed sides of the fabric.
BRIEF SUMMARY OF THE INVENTION
[0011] A TAD fabric meeting the needs discussed above is achieved using a composite fabric for through air drying having a fabric body fabricated from a first material and having a first side portion and a second side portion, wherein the first side portion is fabricated from a second material. Similarly, the second side portion can be fabricated using a third material, or the second material and the third material can be the same material.
[0012] In prior art TAD applications, part of the fabric is not protected by the paper web. More specifically, the edge portions of the, the edge portions of the fabric, when not in contact or otherwise covered by the web, is exposed to the harsher environment of the paper machine running conditions.
[0013] In the present invention, a new edge material is added to the main portion of the fabric. That is, a main central portion of the fabric running in the machine direction has additional side panels added. The paper web generally covers the main middle portion, and overlays, or extends to cover a portion of the side portions.
[0014] In the composite fabric, the first side portion is woven to the fabric body along one side edge. The second side portion is woven to the fabric body along a second side edge. The second side edge is opposite the first side edge. The first and second side portions can be woven to the fabric body on the same loom.
[0015] Likewise, the first and second portions can have the same weave pattern as the fabric body.
[0016] Still further, the first and second side portions can be subjected to the same processing as the fabric body, for example, heat setting, stretching, coating, and the like. When a coating is utilized, the coating, when compared to the composite fabric, has at least one of enhanced release properties, enhanced wear properties and enhanced thermal stability.
[0017] The material used for the body of the composite fabric is at least one of polyester and polyethylenepterathalate (PET).
[0018] The material used for the first side portion is at least one of polyphenylenesulfide (PPS), polyetheretherketone (PEEK), high temperature and hydrolysis resistant polymers, blends using PPS, blends using PEEK, alloys of PPS, alloys of PEEK, and high temperature nylon. The high temperature nylon is at least one of a variant of nylon 66 and an aromatic nylon.
[0019] Additionally, the diameter of the material used for the first side portion can be substantially the same as the diameter of the first material.
[0020] When the first side portion is woven to the fabric body, it is preferably woven in the same plane.
[0021] It is also preferred that the fabric body and the first side portion have substantially the same CFM throughput. However, depending on the design parameters, the CFM throughput of the first side portion can be different from the fabric body, or may be different from the second side portion.
[0022] Additionally, it is preferred that there is a smooth transition between the main portion of the fabric and the side portions.
[0023] The size of the first and second side portions is dependent upon the size of the paper web. In the preferred embodiment, the width of the side portions is approximately 20 - 40 cm when measured in the weft direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The present invention is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of exemplary embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:
[0025] FIG. 1 is a cross section of the prior art;
[0026] FIG. 2 is a plan view of paper side of the composite fabric of the invention;
DETAILED DESCRIPTION OF THE INVENTION
[0027] FIG. 2 depicts a plan view of the composite fabric 10 of the present invention. The composite fabric has a central fabric portion 12 , a first fabric side portion 14 , and a second fabric side portion. MD indicates the machine direction of the composite fabric.
[0028] It is understood that the first fabric side portion 14 and the second fabric side portion 16 are interchangeable, and reference to one may be interchanged with the other. Stated differently, the plan view of FIG. 1 may represent either the paper side or the drum side.
[0029] The central portion 12 can be any woven TAD fabric. The material used for the central portion 12 , also known as the body of the composite fabric, is preferably at least one of polyester and polyethylenepterathalate (PET).
[0030] The first fabric side portion 14 , or new edge material, is added to the central fabric portion 12 . That is, the central fabric portion of the fabric running in the machine direction has additional side panels 14 , 16 . The paper web 18 generally covers the central fabric portion 12 , and overlays, or extends to cover a portion of the side portions 14 , 16 at first and second paper web overlays 20 , 22 .
[0031] In the composite fabric, the first side portion 14 is woven to the central fabric portion 12 along a first side edge 24 . The second fabric side portion 16 is woven to the central fabric portion 12 along a second side edge 26 . The second side edge 26 is opposite the first side edge 24 . The first and second fabric side portions 14 , 16 can be woven to the central fabric body 12 . This weaving of the first and second fabric side portions 14 , 16 to the central fabric body 12 is preferably performed on the same loom on which the central fabric body was woven.
[0032] There is no requirement that the first fabric side portion 14 have the same weave pattern as the central fabric portion 12 or the second fabric side portion 16 . In the preferred embodiment, the first and second fabric portions 14 , 16 have the same weave pattern. Additionally, it is preferable that the first and second fabric portions 14 , 16 have the same weave pattern as the central fabric portion 12 .
[0033] Still further, the first and second fabric side portions 14 , 16 can be subjected to the same processing as the central fabric portion 12 . For example, heat setting, stretching, coating, and the like. When a coating is utilized, the coating, when compared to a composite fabric without the coating, has at least one of enhanced release properties, enhanced wear properties and enhanced thermal stability.
[0034] The material used for the central fabric portion 12 of the composite fabric 10 is preferably at least one of polyester and polyethylenepterathalate (PET).
[0035] The material used for the first fabric side portion 14 and/or the second fabric side portion 16 is preferably at least one of polyphenylenesulfide (PPS), polyetheretherketone (PEEK), high temperature and hydrolysis resistant polymers, blends using PPS, blends using PEEK, alloys of PPS, alloys of PEEK, and high temperature nylon. The high temperature nylon is at least one of a variant of nylon 66 and an aromatic nylon.
[0036] Additionally, the diameter of first fabric side portion fibers 28 used for the first fabric side portion 14 , and the diameter of second fabric side portion fibers 30 used for the second fabric side portion 16 can be substantially the same as the diameter of the central fabric portion fibers 32 used for the central fabric portion 12 .
[0037] When the first side portion is woven to the fabric body, it is preferably woven in the same plane.
[0038] It is also preferred that the fabric body and the first side portion have substantially the same CFM throughput. However, depending on the design parameters, the CFM throughput of the first side portion can be different from the fabric body, or may be different from the second side portion.
[0039] Additionally, it is preferred that there is a smooth transition between the main portion of the fabric and the side portions.
[0040] The size of the first and second fabric side portions 14 , 16 is predetermined and can be based upon the size of the paper web. In the preferred embodiment, the width of each of the fabric side portions 14 , 16 is approximately 10-60 cm when measured in the weft direction, preferably approximately 20-40 cm.
[0041] It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.
|
A through air dryer (TAD) fabric having a composite configuration whereby side fabric portions made of a more resistant material are woven to the main body portion of the fabric. Side fabric portions that are not protected from the paper web, and therefore exposed to harsher environmental conditions than the portion of the fabric covered by the paper web, deteriorate faster. By replacing the side portions that are exposed to harsher environment with more resistant material, the TAD fabric will last longer.
| 3
|
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
Work performed in connection with the development of the present invention was sponsored by grants from the National Science Foundation on "Design, Construction, and Optimization of Magnetic Field Assisted Polishing," (DMI-9402895) and "Tribological Interaction in Polishing of Advanced Ceramics and Glasses (CMS-9414610), and DoD's EPSCoR Program on "Finishing of Advanced Ceramics" (DAAH04-96-1-0323). The government may have rights in this invention.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to magnetic float polishing and, more specifically, to a methodology for conducting magnetic float polishing of workpieces made of magnetic materials such as steel balls for bearing applications.
2. Background
Magnetic float polishing (MPF), sometimes termed magnetic fluid grinding, is a "gentle" polishing technique based on the magneto-hydrodynamic behavior of a magnetic fluid that can float non-magnetic abrasive grains suspended in it. The magnetic fluid is generally a colloidal dispersion of extremely fine (100 to 150 Å) subdomain ferro-magnetic particles, usually magnetite (Fe 3 O 4 ), in water or hydrocarbon based carrier fluids such as kerosene. The ferrofluids are made stable against particle agglomeration by the addition of surfactants.
When a magnetic fluid is placed in a magnetic field gradient, it is attracted towards the side having a higher magnetic field intensity. If a non-magnetic substance (e.g., abrasive grains in this case) is mixed in the magnetic fluid, it is discharged towards the side having a lower magnetic field intensity. When the field gradient is set in the gravitational direction, the non-magnetic material is made to float on the fluid surface by the action of a magnetic buoyancy levitational force. The process is considered highly effective for finish polishing because the levitational force is applied to the abrasive grains in a controlled manner. The forces applied by the abrasives to a workpiece set in the fluid are extremely small (about 1 N or less).
Though extremely effective at providing high-performance, polished surfaces, magnetic float polishing has been used to finish only non-magnetic materials, such as advanced ceramic balls for bearing applications, particularly alumina (Al 2 O 3 ), zirconia (Zr0 2 ), silicon carbide (SiC) and silicon nitride (Si 3 N 4 ). This limitation arises from the nature of the magnetic float polishing technique, which is based on the magnetohydrodynamic behavior of the magnetic fluid. Heretofore, magnetic fluid polishing has not been used in the finishing of magnetic materials, such as steel balls for bearing applications, as magnetic induction upon the workpiece would adversely impact the dynamics of the magnetic float polishing system.
The traditional manufacture of rolling element bearings of hardened chrome steels involves the rounding of cylindrical slugs followed by heat treatment, rough grinding, and finishing. The cylindrical slugs are cut from steel wire of proper size for the desired size of finished balls. These slugs are then rounded while in a soft "as cut" condition, such as by rolling the slugs between two plates which are rotated at low speed relative to each other. The rounded slugs are then heat-treated to harden them whereupon they are ground and lapped to form finished ball bearings. Surface finish is generally achieved by lapping with a diamond paste in oil. Lapping involves working the surface of the balls in a grooved track formed between two working surfaces. As the balls roll along the surfaces of the grooves, a sliding movement of varying magnitude is set up which constitutes the lapping force. This lapping force, in combination with suitable lapping agents, causes gradual altering of the balls to a substantially geometrically spherical shape.
Steel ball bearings are used extensively in industry for a myriad of applications. With the advent of vacuum melting technology, it is now possible to use steels with higher hot hardness, such as M50 tool steels, for applications requiring higher operating temperatures. However, the need to improve performance, conserve energy, and reduce costs to stay competitive has resulted in an increased emphasis on higher efficiency, higher load bearing capability, higher temperature capability, higher precision and rigidity, lower friction and wear, and longer and reliable life. Some believe that rolling contact steel bearings have reached their maximum potential and for many demanding applications alternate materials must be used as bearing elements.
It is in this environment that the use of ceramics with higher hardness, lower density, higher chemical stability, higher modulus, lower friction, and higher wear resistance than steel has arisen, and, in connection with the manufacture of ceramic ball bearings, the use of magnetic float polishing. Until the advent of magnetic float polishing, ceramic balls were finished using low polishing speeds (a few hundred rpm) and diamond abrasive as a polishing medium. It takes a considerable time (some 12-15 weeks) to finish a batch of ceramic balls in this fashion, and the use of diamond abrasives at high loads often results in deep pits, scratches and microcracks on the ceramic ball surface. Magnetic float polishing was developed to allow for higher removal rates and shorter polishing cycles by using high polishing speeds with very low level controlled forces and abrasives not much harder than the workpiece. Notwithstanding the successful use of ceramics in ball bearing applications, there remain drawbacks, including a relatively high cost of manufacture, their inherent brittleness, and lack of reliability in performance.
It is an object of the present invention to provide a method for conducting magnetic float polishing on magnetic workpieces, such as a steel balls, so that the advantages of magnetic float polishing may be applied to broader technologies such as the manufacture of rolling contact steel bearings to increase the potential for the use of lower cost steel ball bearings in demanding applications.
It is a further object of the invention that the method be performed utilizing existing magnetic float polishing hardware.
SUMMARY OF THE INVENTION
The present invention encompasses the magnetic float polishing of magnetic materials. This is accomplished by isolating the magnetic workpiece from any appreciable magnetic induction and subsequently polishing the magnetic workpiece utilizing the action of a magnetic buoyancy levitational force with a conventional magnetic float polishing apparatus.
The magnetic workpiece(s) is immersed in a magnetic fluid suspension which comprises a colloidal dispersion of magnetic particles in a carrier fluid and a quantity of non-magnetic abrasive grains. A magnetic field is applied to the magnetic fluid suspension to cause the magnetic particles to be attracted downward to an area of higher magnetic field intensity and to thereby create an upward magnetic buoyancy levitational force on the abrasive grains which pushes them to an area of lower magnetic field intensity (to the surface of the magnetic fluid suspension) and into a polishing position. The magnetic workpiece is set in the magnetic fluid suspension where it can be contacted by the abrasive grains; however, it is isolated from the magnetic field so that it receives only negligible, if any, magnetic induction. With the magnetic workpiece so isolated, magnetic fluid polishing is conducted under the action of the magnetic buoyancy levitational force.
The magnetic float polishing of magnetic materials may be conducted utilizing conventional apparatus of the type having a chamber for holding the magnetic fluid suspension and workpieces, beneath which a magnetic field is applied, and wherein a non-magnetic float, such as an acrylic float, is positioned in the suspension within the chamber. The chamber is filled with the magnetic fluid suspension and the float is set therein. The workpieces are located above the top surface of the float. The conventional purpose of the float is to produce a more uniform and larger polishing pressure upon the workpieces by taking the larger buoyant force near the magnetic poles and evenly distributing it to the workpieces.
In connection with the present invention, the magnetic workpieces are located in an area of negligible magnetic field intensity. In one aspect of the invention, and in additional to its conventional purpose, the float itself is also used to facilitate the establishment of the area of negligible magnetic field intensity. This is done by making the float of a sufficient thickness such that when the magnetic field is applied there is no appreciable magnetic field gradient in the area above the float where the workpieces are set. Increasing the thickness of the float increases the distance between the magnets and the top of the float, thereby minimizing the magnetic force component above the float. A spindle-driven shaft is fed down into the chamber to establish contact with the workpieces and presses them down to reach a desired force or height. The workpieces are polished under the action of the magnetic buoyancy levitational force when the spindle rotates.
In another aspect of the invention, during a final polishing stage a harder shaft material is used, preferably an advanced ceramic such as SiC, B 4 C, Al 2 O 3 , or Si 3 N 4 . Also during this stage no abrasives are used, or, alternatively, softer chemo-mechanical abrasives are utilized, to obtain the best sphericity and surface finish possible.
A better understanding of the present invention, its several aspects, and its objects and advantages will become apparent to those skilled in the art from the following detailed description, taken in conjunction with the attached drawings, wherein there is shown and described the preferred embodiment of the invention, simply by way of illustration of the best mode contemplated for carrying out the invention. As will be realized, the invention is capable of modifications in various obvious respects, all without departing from the scope of the invention. Accordingly, the description should be regarded as illustrative in nature and not as restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic of a magnetic float polishing apparatus.
FIG. 2 is a contour map of the magnetic field intensity by ANSYS simulation of magnetic float polishing using permanent magnets.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Before explaining the present invention in detail, it is important to understand that the invention is not limited in its application to the details of the construction and the steps illustrated herein. The invention is capable of other embodiments and of being practiced or carried out in a variety of ways. It is to be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation.
FIG. 1 is a schematic of a magnetic float polishing apparatus. Permanent magnets 10 are supported on a steel yoke 12 within an non-magnetic base 14. The magnets 10 are located with alternate N and S poles underneath a float chamber 16. Although permanent magnets are illustrated, it is within the scope of the invention to use an electromagnet instead of permanent magnets in order to achieve some flexibility in providing the desired magnetic field. A guide ring 18 is mounted on top of the float chamber 16 to hold a quantity of magnetic fluid 20. The base 14 and guide ring 18 define the float chamber 16 and are preferably made of aluminum, non-magnetic austenitic stainless steel, ceramic or acrylic materials. The magnetic fluid 20 preferably contains 5-10% by volume of fine abrasive particles 22. As used herein the term "magnetic fluid suspension" means the combination of the magnetic fluid 20 and abrasive particles or grains 22. Typical abrasive grains 22 are B 4 C and SiC, but the invention is not limited to the use of any particular abrasive materials. Workpieces 24 are held in a 3-point contact between a lightweight, non-magnetic float 26, such as an acrylic float, at the bottom, a rubber ring 28 glued to the inner surface of the guide ring 18 on the side, and the beveled edge 30 of a drive shaft 32 at the top. The drive shaft 32 is connected to the spindle 34 of a milling machine or other spindle capable of operating in a speed range up to 6,000 to 10,000 rpm. As described hereinabove, the magnetic fluid 20 is a colloidal dispersion of extremely fine (100 to 150 Å) subdomain ferromagnetic particles, usually magnetite (Fe 3 O 4 ), in a carrier fluid, such as water or kerosene. It is made stable against particle agglomeration by coating the particles with an appropriate surfactant.
When a magnetic field is applied, the magnetic particles in the magnetic fluid 20 are attracted downward to an area of higher magnetic field intensity and an upward magnetic buoyancy levitational force is exerted on all non-magnetic materials to push them upward to an area of lower magnetic field intensity. The abrasive grains 22 and float 26, being non-magnetic materials, are levitated by the magnetic buoyancy levitational force. The drive shaft 32 is fed down to contact with the workpieces 24 (3-point contact) and presses them down to reach the desired force or height. The workpieces 24 are polished by the abrasive grains 22 under the action of the magnetic buoyancy levitational force when the spindle 34 rotates. Reference is made Applicants' copending U.S. patent application Ser. No. 08/940,254, filed Sep. 30, 1997, which discloses magnetic float polishing processes and materials therefor, the same being incorporated herein by reference.
In connection with the present invention, the workpieces 24 are magnetic materials, and, for illustrative purposes, ball blanks such as steel balls for bearing applications. The magnetic workpieces 24 are immersed in the magnetic fluid suspension atop the float 26, but are isolated from the magnetic field to avoid any appreciable magnetic induction. This allows the magnetic workpieces 24 to be finished in a manner similar to ceramic balls. Once the magnetic field is applied to the magnetic fluid suspension, the magnetic particles therein are attracted downward to an area of higher magnetic field intensity (or magnetic flux density). This creates an upward magnetic buoyancy levitational force on the abrasive grains 22 and the float 26 which pushes them to an area of lower magnetic field intensity. Abrasive grains 22 between the float 26 and the workpieces 24 are pushed onto the workpieces 24 and polishing or finishing occurs as the abrasive grains 22 and workpieces 24 move against each other.
The magnetic workpieces 24 are isolated from magnetic induction by ensuring that the workpieces 24 are a spaced far enough away from the top of the magnets 10 that they are in an area of negligible magnetic field intensity. In the case of finishing non-magnetic materials, such as ceramic balls, the downward acting forces are those due to the weight of the balls (gravity force) and the polishing forces acting on the balls. The latter is typically ˜1 N/ball. In the case of magnetic materials, such as steel balls, there are two additional forces to consider. First, as the density of magnetic balls, such as steel balls, is much higher (˜40%) than ceramic balls, the downward gravity force is higher. Secondly, there is an additional downward magnetic force due to the attraction of the magnetic material towards the magnets. To effectively accomplishing magnetic float polishing of magnetic balls, the magnetic buoyancy levitational force has to overcome these two extra forces. Accordingly, the net magnetic buoyancy levitational force acting on the bottom of the float 26 upwards should be equal to or greater than the sum of the gravity force acting on the balls, the downward magnetic force due to magnetic induction, plus the polishing force applied on the balls by the abrasive. Otherwise, the float 26 will sink to the bottom of the chamber 16 and will not be free to rotate during polishing. A minimum gap (˜0.5-1.0 mm) between the bottom of the chamber 16 and the float 26 should also be maintained to allow the float 26 to properly operate. If the magnetic workpieces 24 are located at or near the distance where the magnetic field intensity is very small or negligible, then the downward magnetic force component due the balls is negligible. This can be accomplished by increasing the distance between the magnets 10 and the top of the float 26.
Since the magnetic field decreases rapidly as the distance from the magnets 10 increases, one way to facilitate isolation of the magnetic workpieces 24 from the magnetic field is by making the float 26 of a thickness sufficient to effectively minimize the downward magnetic force component of the magnetic ball material. Consequently, when the magnetic field is applied there is no appreciable magnetic field gradient in the area above the float 26 and negligible magnetic induction upon the magnetic workpieces 24. Another way to minimize magnetic induction upon the balls is to vary the thickness of the floor of the magnetic fluid chamber 16. Still further, the position of the workpieces 24 in the chamber 16 may also be controlled by careful setting of the drive shaft 32, which is fed down to contact with the workpieces 24 and presses them down to reach the desired force or height. Whatever means is used to achieve it, the critical aspect is to obtain a physical separation between the balls and the top of the magnets that is sufficient to effectively isolate the balls from any appreciable magnetic induction.
The magnetic field strength is maximum at the face of the magnets 10 and decreases rapidly with increasing distance from the magnets 10 till it becomes vanishingly small at higher distance. As one example of the preferred embodiment, the magnetic flux density at the face of the magnets 10 (6 mm width) is ˜1.5 KGauss. At 1 mm it drops to 0.7, at 2.5 mm it is 0.26, at 6 mm it is 0.175 and at 7.5 mm it is practically zero. The conventional magnetic float polishing apparatus as hereinabove described is constructed to take into account these dimensions such that during operation the top surface of the float 26 upon which the workpieces 24 are set defines an area of negligible magnetic field intensity.
FIG. 2 is a typical magnetic flux density plot from FEM analysis illustrating the varying magnetic field intensity achieved in connection with the practice of the preferred embodiment of the invention. Permanent magnets 10 are supported on the steel yoke or plate 12 with alternate N and S poles underneath the float chamber 16. The magnetic fluid 20 is contained in the chamber 16, and set in the magnetic fluid 20 is the acrylic float 26. The unit of measurement is the Tesla.
As is seen in FIG. 2, the magnetic flux density in the area just above the magnets 10 is in the range of 0.45 to 0.55. The magnetic flux density dissipates over distance such that at the bottom surface of the float 16 the flux density ranges from about 0.25 to 0.45. A critical reading is obtained at the top surface of the float 16 which is where the workpieces 24 are located during polishing. At this point the flux density ranges from around 0.00 to 0.15. The upper surface of the float 16 and the area thereabove is thus defined as an area of negligible magnetic field intensity. When positioned in this area the workpieces 24 are thus isolated from any appreciable magnetic induction. In conjunction with the present invention, the term "negligible" or "not appreciable" when used to refer to magnetic induction upon the workpieces 24 means an absence of significant induction. Significant induction is that which would exceed the net magnetic buoyancy levitational force acting on the bottom of the float 26 upwards when summed with the weight of the balls and the force applied on the balls by the abrasive.
Another aspect of the present invention further facilitates the finishing of magnetic materials by magnetic float polishing. While in the case of ceramic balls a non-magnetic austenitic stainless steel shaft 32 is generally used, such is not acceptable in the final finishing stages for the polishing of steel balls. While for roughing and semi-finishing stages it is possible to use a steel shaft 32, in order to obtain the best sphericity and finish it was found necessary to use a harder shaft material, perferably an advanced ceramic such as SiC, B 4 C, Al 2 O 3 , or Si 3 N 4 , for final stage finishing. Additionally, it is preferred that during this stage to use either no abrasive or softer abrasives that can participate in the chemo-mechanical action between the balls, the abrasives and the environment. While in the case of ceramic balls, it is desired to minimize the influence of hard abrasives in causing brittle fracture leading to microfracture of the balls, in the case of softer steel balls it is necessary to minimize the plastically deformed groove formation or scratching made by the harder abrasives. Once the material from the balls is removed to the final dimensions, improvements in sphericity and finish can be obtained by taking advantage of microbrinelling of the surfaces of the balls by the hard advanced ceramic shaft 32. In this way, fine amounts of material are either removed from the tips of the surface or deformed locally (or redistributed) to obtain the best sphericity and finish. Without this it is practically impossible to obtain bearing grade balls economically.
Thus, the present invention can be utilized to successfully polish magnetic materials such as stainless steel balls by magnetic float polishing. The technique is far superior to the state of the art where serious problems are encountered due to residual stresses induced during polishing and various heat treatment cycles to which the balls are subjected. The invention enables use of the balls in their hardened state for polishing, thereby eliminating substantial processing time.
While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made without departing from the spirit and scope of the invention. It is understood that the invention is not limited to the embodiment(s) set for herein for purposes of exemplification, but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled.
|
A methodology for conducting magnetic float polishing of magnetic materials. This is accomplished by isolating the magnetic workpiece from any appreciable magnetic induction and subsequently polishing the magnetic workpiece utilizing the action of a magnetic buoyancy levitational force with conventional magnetic float polishing apparatus.
| 5
|
BACKGROUND OF THE INVENTION
The invention relates to a method for increasing the utilization of the braking torque of a retarder in a motor vehicle. The invention further relates to conducting away heat generated in the retarder during the braking operation using a coolant. The invention also relates to operating secondary loads in a cooling system even if not required.
In order to cool vehicle components, for example hydrodynamic brakes, internal combustion engines, etc., use is generally made today of coolant circuits comprising a coolant, preferably water with appropriate antifreeze additives. In such circuits, a specific quantity of coolant per time unit flows through the component to be cooled. The coolant absorbs heat that is to be conducted away from the component and conveys the heat to a radiator, for example a ribbed radiator, or to a heat exchanger. The radiator or exchanger outputs the absorbed and conveyed quantity of heat into the environment or to another coolant circuit. The cooling power of such a system is determined essentially by the efficiency of the individual system components, for example the delivery capacity of the coolant pump.
In order to protect the engine cooling system against overheating when a retarder is switched on, it has therefore been proposed in
WO 94/27845
to reduce the retarder braking power as a function of the engine speed, and thus the speed of the coolant pump.
A disadvantage with this method or this control system is that the retarder braking torque is reduced very early, and as a result the braking power of the retarder is utilized only insufficiently.
SUMMARY
The object of the present invention is therefore to specify a method and a device for carrying out the method with which the disadvantages of the prior art are avoided and the retarder braking torque can be utilized better than hitherto, that is to say the retarder availability is increased.
This object is achieved according to the invention in that at least one secondary load and/or at least one of the following devices of the cooling system in the vehicle:
a switched fan
a switched thermostat
a coolant pump
a bypass valve in the cooling circuit
is actuated as a function of the instantaneous or future braking requirement.
It is particularly advantageous if at least the following retarder operating states:
switching on the retarder
requested or actually selected braking level of the retarder
are distinguished. In terms of actuation, the following variants are conceivable:
everything depends on the engine control system. It controls the engine, the fan and the retarder; or
each of the aforesaid assemblies has its own control system and these communicate with one another; or
retarder and fan have a common control system.
A particularly interesting variant consists in not sensing the instantaneous braking requirement or not exclusively sensing the instantaneous braking requirement, but also the future braking requirement in terms of predictive driving. The future braking requirement can be defined here by means of a navigation system in which the route ahead is examined by means of, for example, a satellite system (so-called global positioning system).
According to the invention, the retarder availability with respect to the maximum possible level of braking torque can be increased by virtue of the fact that a switched fan, for example that of the vehicle radiator, is connected into the circuit by the retarder electronics when the retarder switch-on instruction is present, as a result of which the efficiency of the cooling system is increased.
In order to avoid fuel being used unnecessarily by the fan which is connected into the circuit when the retarder is switched off, there is provision that when the retarder is OFF instruction is present, the fan is enabled again or switched off. Actuation takes place then only by means of the sensors of the engine cooling system. As an alternative to switching off or enabling the fan when the retarder is switched off, there may also be provision to switch off or enable the fan when the retarder braking torque drops below a specific value that is predefined at a low level.
In addition to a pure on/off logic system as described above, it is advantageously provided that in the case of multi-step fans or infinitely adjustable fans the actuation of the fan is carried out as a function of the requested retarder braking power, for example the selected retarder braking level. In principle, the fan according to the invention operates with a high rotational speed at high retarder braking levels, whereas at low retarder braking levels the fan is either entirely enabled or runs with only a reduced rotational speed.
In a further, developed embodiment of the invention, there may be provision for the thermostat which is preferably embodied as a 2/3-way valve in, for example, the coolant circuit of the vehicle cooling system to be switched as a function of retarder operating states.
There may be provision that if the cooling system is running in the bypass mode, i.e. the coolant fluid is being conducted past the vehicle radiator, the 2/3-way valve is actuated, after the retarder is switched on, in such a way that coolant fluid flows through the vehicle radiator in order to increase the cooling power of the cooling system.
The retarder availability can be increased further if not only the fan and the bypass valve are actuated as a function of the braking requirement but also a coolant pump, if said pump is one whose rotational speed can be actuated or regulated. In such embodiments there may be provision that the rotational speed of the coolant pump is increased when the retarder is switched on and decreased to the normal level when the retarder is switched off. With a coolant pump whose rotational speed can be adjusted, it is also possible to select the rotational speed as a function of the selected retarder braking level.
So that the heat generated by the retarder can be conducted away better than hitherto and not exclusively by means of the cooling system and from there into the environment, there is provision that secondary loads in the vehicle which do not have to be permanently in use are switched on if the retarder is switched on, in order to convert the braking work into useful work, with the result that the energy can be utilized more appropriately.
If the retarder is a secondary retarder, and there is no need whatsoever to restrict the invention to this, a separate heat exchanger is generally assigned to said secondary retarder. If the heat exchanger circuit has, like the engine cooling system, a bypass, in a particular refinement of the invention it is possible to operate the bypass similarly to the operation of the radiator bypass valve. The heat exchanger bypass in this instance is connected in a way analogous to the radiator bypass valve. That is, coolant is conducted through the heat exchanger when relevant for the braking mode of the retarder, and past the heat exchanger when the retarder is switched off.
In addition to the method described above, the invention also makes available a control device for carrying out the method. According to the invention there is provided a control or regulating system that comprises means, for example sensors, for sensing the retarder operating states or the instantaneous or future braking state. The system further comprises a control/regulating device that actuates vehicle assemblies such as secondary assemblies and/or devices of the cooling system as a function of the retarder braking states detected.
BRIEF DESCRIPTION OF THE DRAWINGS
An example of the invention will now be explained with reference to the drawings, in which:
FIG. 1 is a schematic view of a vehicle cooling system according to the invention with a retarder which operates as a primary retarder.
FIG. 2 is a schematic view of a vehicle cooling system according to the invention with a retarder which operates as a secondary retarder.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 represents a drive unit composed of an engine 1 and a cooling circuit 3 . The cooling circuit 3 comprises a radiator 5 , a coolant pump 7 , which is configured here as a coolant pump regulated whose rotational speed is regulated, and an equalization vessel 9 , which always ensures that there is adequate overpressure on the pump intake side. The embodiment illustrated in FIG. 1 is a primary retarder 13 which is arranged in the cooling circuit. By means of the switch-over valve 11 it is possible to conduct coolant past the vehicle when the retarder is switched off. The invention is, however, not restricted in any way to primary retarders which, as in FIG. 1, are arranged in the coolant circuit of the engine. The invention can also be applied even if the coolant circuit is separated from the engine and retarder.
A bypass line 40 leads past the radiator and branches at the point 42 . At the point 42 , a switch-over valve or thermostat 44 is arranged which can be configured as a 3/2-way valve. The 3/2-way valve has the function of controlling the coolant flow in such a way that it can be conducted either through the radiator or else through the bypass line 40 past the radiator. It is generally the case that the 3/2-way valve conducts the coolant stream to the radiator 5 partially or for the greater part in operating phases in which a large amount of heat is conducted away. In the phase in which a small amount of heat is conducted away, the 3/2-way switch-over valve 44 directs the coolant to the engine 1 or to the pump 7 via the bypass line. The 3/2-way valve can be embodied as an expansible-material-regulated valve or as an electrical or pneumatic continuously variable valve.
The fan 15 is arranged downstream of the vehicle radiator 5 as a further assembly of the cooling system. The fan 15 is preferably of switchable design. The retarder operating state, i.e. switched-on retarder, switched-off retarder, braking level of the retarder, is detected, for example, by the sensor 22 or by the retarder operator lever which is not illustrated here, tapped and transmitted to the control/regulating unit 24 .
As a function of the sensed or transmitted signal, the control/regulating unit 24 controls the various assemblies of the cooling system such as the fan, 3/2-way valve or else vehicle secondary assemblies which are not continuously in use and via which heat can be conducted away.
For example, the fan 15 can be activated when the retarder is switched on, and the cooling power of the vehicle cooling system can thus be increased. As a result, the full braking power or the maximum braking torque of the retarder is available immediately when the retarder is switched on.
If the switch-over valve 44 is in the bypass position and the heat is being conducted past the radiator via the bypass 40 , said switch-over valve 44 can, like the fan 15 , be activated so that the coolant is conducted through the radiator 5 . Of course, in a particular advantageous refinement, it is possible to co-ordinate the activation of the switch-over valve 44 and thus the fan 15 . In this way, for example, the switch-over valve 44 can be switched to a setting in which there is a flow through the radiator 5 and the rotational speed of the fan 15 is then increased. If the requested braking power of braking torque drops below a specific value, the fan 15 can firstly be switched off. The switch-over valve 44 is not switched to bypass mode again unit the retarder is completely switched-off.
In one developed embodiment, there may be provision for the rotational speed of the fan to be controlled as a function of the respective retarder braking level. For example, the rotational speed of the fan can be increased at a high retarder braking level, i.e. high braking torque request, and thus a requirement for a large amount of heat to be conducted away, while it is reduced when low braking torque is requested.
In addition to the fan 15 and the switch-over valve 44 , a rotational-speed-regulated coolant pump 7 is provided in the embodiment of a vehicle cooling system illustrated in FIG. 1 .
The rotational-speed-regulated coolant pump 7 is also actuated by the control/regulating device 24 . It is possible, for example when a retarder ON instruction is present, to adjust the rotational speed of the coolant pump to a predetermined, significantly higher value than during normal driving mode. The delivery capacity in the coolant circuit is increased and more heat can be conducted away than during the normal mode.
If the braking torque or the requested braking power drops below a specific value, the rotational speed of the pump 7 can be reduced to the value required solely by the engine cooling system when the retarder is switched off. By reducing both the rotational speed of the pump 7 and that of the fan 15 and switching over the bypass valve 44 when the retarder OFF instruction is present, it is possible to minimize the fuel consumption in the driving mode because components which are not required do not operate at the same time.
On the other hand, by connecting into the circuit the above-mentioned assemblies when a retarder ON instruction is present or at a predefined braking level, the retarder availability is increased in comparison with the previously known control/regulating systems.
FIG. 2 illustrates an alternative embodiment of the invention. The coolant circuit 3 of the engine 1 is illustrated again.
In contrast with the, retarder illustrated in FIG. 1, the retarder 13 in FIG. 2 is a so-called secondary retarder which is preferably arranged on the vehicle transmission or on the output shaft. The conduction away of heat in such a system is preferably carried out by means of a separate retarder coolant circuit 50 which outputs the heat to the vehicle cooling system 3 via the heat exchanger 52 .
As in FIG. 1, the fan 15 , the switch-over valve 44 and the rotational-speed-regulated coolant pump 7 are actuated by means of the control/regulating device 24 given specific retarder operating states which are communicated to the control/regulating device 24 either by the sensor 22 or, for example, the retarder control operating lever.
In addition to this, in the embodiment according to FIG. 2 there may be provision that a switch-over valve 54 is also actuated in the retarder cooling circuit 50 , specifically when the retarder is switched on, in such a way that the coolant is not conducted via the bypass 56 but rather via the-heat-exchanger 52 .
In addition to the actuation of the assemblies of the cooling system which have been described in detail above, there may be provision that secondary assemblies in the vehicle which do not have to be continuously used are also actuated in order to promote the conduction away of heat. This measure can further increase the retarder availability.
The invention thus discloses for the first time a system with which the braking effect of a retarder can be utilized to a maximum degree directly after switching on by virtue of the fact that additional assemblies of the cooling system or secondary assemblies of the vehicle are actuated.
|
The invention relates to a method and a device for increasing the use of the braking moment of a retarder in an automobile. According to this method, the heat produced by the retarder during braking is dissipated using a coolant. The method is characterized in that at least one auxiliary consumer and/or at least one of the following devices of the cooling system—a connected fan, a connected thermostat, a coolant pump, a bypass-valve—is controlled in dependence on the mode of the operation of the retarder.
| 1
|
FIELD OF INVENTION
[0001] The present invention relates to radio frequency identification (RFID) articles and, in particular, to encapsulated RFID articles having enhanced temperature resistance.
BACKGROUND OF INVENTION
[0002] Radio frequency identification (RFID) tags include a microchip combined with an antenna. The tag is generally included in packaging that is designed to permit the RFID tag to be attached to an object to be tracked. The tag's antenna picks up signals from an RFID reader or scanner and then returns the signal, usually with some additional data that identifies the contents of the package or otherwise identifies the item tagged.
[0003] RFID tags typically come in two types—passive tags and active tags. Passive tags require no internal power source, whereas active tags require a power source. Since passive RFID tags have no internal power supply, they can be quite small in size, thereby enabling them to be used in a wide array of applications. For example, RFID tags have been used in passports, electronic payment systems, cargo tracking systems, automotive applications, animal tracking applications, and have even begun being used in humans for providing health information.
[0004] Nevertheless, due to the sensitivity of the components used to form the RFID tags, the circuitry and/or antennas, the RFID tags can become damaged or inoperable when subjected to environmentally unfriendly environments, such as those with high temperatures and/or those operated under sterilization conditions. In many prior art RFID articles, the RFID tags are located within two-piece structures that, due to the manufacture of the article, includes seams where the two pieces are joined. As used herein, “seams” are those areas where two pieces of a thermoplastic structure are joined together. These two pieces may be mechanically or chemically attached to one another, but the resulting structure still includes a seam. While acceptable for standard use, during sterilization events, the RFID article is subjected to high heat and/or steam, which causes the seams to expand slightly, enabling the sterilization medium to enter into the cavity of the RFID article, thereby damaging the electrical components of the RFID tag and rendering the RFID article non-functioning after just a few sterilization cycles.
[0005] In addition, due to the seams, the RFID articles of the prior art have a structural weakness at the seam such that even if a higher impact thermoplastic material or materials is used to form the RFID housing, the RFID articles have lower break strengths as the RFID article will typically fail at the point of the seam. This is especially true for articles that have been subjected to sterilization conditions that help weaken the article along these seams.
[0006] Accordingly, it would be beneficial to provide an RFID article having enhanced thermal resistance and/or break strength. It would also be beneficial to provide an RFID article that may be subjected to repeated exposures to sterilization conditions without damage to the RFID tag. It would also be beneficial to provide an RFID article that may be easily manufactured.
SUMMARY OF THE INVENTION
[0007] Encapsulated radio frequency identification (RFID) articles having enhanced break strength and/or temperature resistance and methods of making these articles. The RFID articles include an RFID tag embedded located in a thermoplastic substrate or housing to form the RFID article. In one embodiment, the RFID article includes an over-molded seal that enables the RFID article to have enhanced break strength and/or temperature resistance such that the articles are able to sustain repeated exposure to high temperatures and/or sterilization procedures, thereby enabling the RFID articles to be utilized in applications heretofore unavailable. In other embodiments, the RFID articles are made using an injection molding process that provides very thin encapsulated RFID tags that also exhibit an increased level of temperature resistance.
[0008] Accordingly, in one aspect, the present invention provides a radio frequency identification article including a housing comprising a first piece having a cavity and a second piece, a radio frequency identification tag located in the cavity of the first piece, the radio frequency identification tag comprising a microchip and an antenna, and a sealing material encompassing at least a portion of the housing, the sealing material helping to secure the first piece to the second piece and helping prevent moisture from contacting the radio frequency identification tag; wherein the radio frequency identification article has enhanced break strength and thermal resistance.
[0009] In another aspect, the present invention provides a radio frequency identification article including a housing comprising a substrate, a radio frequency identification tag located on the substrate, the radio frequency identification tag comprising a microchip and an antenna, a barrier layer adjacent the substrate and covering the radio frequency identification tag, and a sealing material encompassing the housing and the barrier layer, the sealing material helping to secure the first piece to the second piece and helping prevent moisture from contacting the radio frequency identification tag; wherein the radio frequency identification article has enhanced break strength and thermal resistance.
[0010] In still another aspect, the present invention provides a method of forming a radio frequency identification article including the steps of providing a first piece capable of holding a radio frequency identification tag, placing a radio frequency identification tag in connection with the first piece; wherein the radio frequency identification tag comprises a microchip and an antenna, securing the radio frequency identification tag with the first piece using a second piece, and overmolding a sealing material to encompass at least a portion of the first piece and the second piece to provide enhanced break strength and thermal resistance; wherein the radio frequency identification article has enhanced break strength and thermal resistance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a top view of one embodiment of a radio frequency tag placed on an underlying substrate according to one embodiment of the present invention.
[0012] FIG. 2 is a perspective view of a substrate layer and two barrier layers used to form an RFID article according to one embodiment of the present invention.
[0013] FIG. 3 is a close-up view of a substrate layer and two barrier layers used to form an RFID article according to one embodiment of the present invention.
[0014] FIG. 4 is a top view of one embodiment of a radio frequency identification article according to one embodiment of the present invention.
[0015] FIG. 5 is a perspective view of a substrate layer and one barrier layers used to form an RFID article according to an alternative embodiment of the present invention.
[0016] FIG. 6 is a top view of one embodiment of a radio frequency identification article according to an alternative embodiment of the present invention.
[0017] FIG. 7 is a cross-sectional view of an RFID article and a mold used to make the RFID article according to an alternative embodiment of the present invention.
[0018] FIG. 8 is a cross-sectional view of an RFID article according to yet another embodiment of the present invention.
[0019] FIG. 9 is an exploded view of an RFID article according to yet another embodiment of the present invention.
[0020] FIG. 10 is a perspective view of the housing of an RFID article according to yet another embodiment of the present invention.
[0021] FIG. 11 is a cross-sectional view of an RFID article according to still another embodiment of the present invention.
[0022] FIG. 12 is an exploded view of an RFID article according to still another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The present invention is more particularly described in the following description and examples that are intended to be illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. As used in the specification and in the claims, the term “comprising” may include the embodiments “consisting of” and “consisting essentially of.” All ranges disclosed herein are inclusive of the endpoints and are independently combinable. The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value; they are sufficiently imprecise to include values approximating these ranges and/or values.
[0024] As used herein, approximating language may be applied to modify any quantitative representation that may vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about” and “substantially,” may not be limited to the precise value specified, in some cases. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value.
[0025] The present invention provides a radio frequency identification (RFID) article capable of withstanding repeated exposure to high heat events without damage to the electrical components of the RFID article. The RFID article includes a housing or substrate constructed from a thermoplastic material, an RFID tag located in the housing, and an overmolded seal around the housing that helps secure the RFID tag in the housing while also providing enhanced protection to the RFID tag during repeated exposure to high heat conditions, such as those associated with sterilization.
[0026] Accordingly, in one aspect of the present invention, the RFID article includes a housing capable of holding an RFID tag. In one embodiment, the housing is a one-piece housing capable of holding an RFID tag. In an alternative embodiment, the housing is a two-piece housing having a cavity into which the RFID tag may be placed. In both embodiments, the RFID tag includes a microchip, an antenna and, for active tags, a power source.
[0027] In another aspect of the present invention, the RFID tag includes an overmolded seal around the housing that is designed to help secure the RFID tag in the housing as well as provide enhanced break strength and/or thermal resistance. The type of seal utilized may vary depending on the type of housing, but in each embodiment, the seal includes a thermoplastic material that is overmolded after the RFID tag has been placed in the housing. The result is an RFID tag having enhanced break strength and/or thermal resistance. The seal material is shaped to either encompass, in whole or in part, the housing or, in select two-piece alternative embodiments, to provide a locking mechanism to help secure the two pieces to one another.
[0028] Accordingly, in one embodiment, the RFID article includes a one-piece housing capable of holding an RFID tag. The one-piece housing may include a thermoplastic substrate onto which the RFID tag is located, or may include a thermoplastic article having a cavity into which the RFID tag is located. In each instance, the seal includes a thermoplastic material that is overmolded around the housing to form a resulting barrier structure that provides increased break strength to the RFID article through the characteristics of the overmolded seal material while also providing enhanced thermal resistance since the components of the RFID tag are encased with the seal material, which acts as a barrier layer during sterilization conditions, thereby giving the material enhanced thermal resistance. In addition, since an overmolding step is used, there are two layers of thermoplastic material, which increases the break strength of the RFID article. And depending on the type of overmolding step or steps performed, seams can be substantially reduced or even eliminated, thereby further increasing the break strength and/or thermal resistance of the RFID article.
[0029] The overmolded seal layer in this embodiment is designed to encompass or substantially encompass the substrate and RFID tag. By encompassing the substrate and tag, the material characteristics of the seal material, as it relates to break strength and moisture barrier, provide the enhanced break strength and/or thermal resistance to the RFID tag and, therefore, the RFID article. If a stronger RFID article is desired, a stronger substrate material and/or sealing material may be used. If greater temperature resistance and/or moisture barrier are desired, a plastic material having high heat deformation temperature and/or moisture prevention may be used.
[0030] In another embodiment, the RFID article includes a two-piece housing capable of holding an RFID tag. In this embodiment, the housing includes a first piece having a cavity into which the RFID tag may be placed. The housing also includes a second piece that connects to the first piece to capture the RFID tag within the housing. As this embodiment provides a structure having seams or seams, the overmolded seal is selected to help reduce the issues associated with the seams, for break strength and/or for thermal resistance. Accordingly, in one aspect, the overmolded seal provides mechanical features that help secure the two pieces of the housing to one another, thereby increasing the mechanical or break strength of the RFID article. In another aspect, the seal provides additional protection to the seams by helping to cover or encase the seams, thereby increasing the thermal resistance of the RFID article.
[0031] In the two-piece housing embodiment, the seal material is shaped to match, or substantially match a corresponding portion of the two housing pieces to help provide a mechanical lock to the two pieces. In this embodiment, the two housing pieces beneficially join one another such that they form a nonlinear shape at the location where the two pieces are joined. Accordingly, in a first embodiment, when the two pieces are joined to one another, at least one curved or angled edge is formed. As such, when the sealing material is overmolded to the housing, the sealing material helps “lock” the two pieces to one another, thereby resulting in a break strength comparable to that of the overmolded seal material, rather than the amount of force simply needed to break the adhesive or mechanical bond between the two pieces of the housing. In addition, by angling the connection between the two pieces, a longer path is created, thereby increasing the distance any moisture needs to traverse in order to contact the RFID tag components. In one embodiment, the two housing pieces form a V-shaped edge. In another embodiment, a W-shaped edge is formed. In still another embodiment, a C-shaped or U-shaped edge is formed. Other non-linear shapes are contemplated to be within the scope of the claimed invention provided an overmolded plastic material is capable of contacting all or substantially all of the non-linear surface to increase the break strength of the resulting RFID article, such as curved edges or angled edges or the like.
[0032] In addition, or in an alternative embodiment, the sealing material may also be shaped such that it connects to the housing in one or more locations to help provide additional structure designed to increase the break strength of the RFID article. For example, in one embodiment, the housing includes a plurality of holes. The sealing material is selected such that, during the overmolding process, the sealing material fills these holes. Since the overmolding occurs with a sealing material that is liquefied during the overmolding process, the sealing material is selected to be capable of flowing into and filling any holes. Then, after the sealing material has cooled, the sealing material forms a solid structure that includes one or more additional locking mechanisms to help secure the housing pieces to one another.
[0033] In another embodiment, as with the one piece housing embodiments, the sealing material may be overmolded such that it encompasses all, or substantially all, of the housing after the RFID tag has been placed in the housing. As in the one-piece embodiment, encompassing the housing and tag enables the material characteristics of the seal material, as it relates to break strength and moisture barrier, to help provide the enhanced break strength and/or thermal resistance to the RFID article. In these embodiments, the two housing pieces may have seams that are nonlinear, as with previous two housing embodiments. However, linear seam embodiments are also capable since the seal material itself is providing the enhanced break strength and/or thermal resistance.
[0034] Accordingly, the present invention provides a plastic RFID article that includes a housing constructed from a plastic resin and a seal that is also selected from a plastic resin. Both the housing and the seal are selected from plastic resins capable of being molded. In one embodiment, the plastic resin may be selected from a wide variety of thermoplastic resins, blend of thermoplastic resins, thermosetting resins, or blends of thermoplastic resins with thermosetting resins. The plastic resin may also be a blend of polymers, copolymers, terpolymers, or combinations including at least one of the foregoing plastic resins. Examples of the plastic resin include, but are not limited to, polyacetals, polyacrylics, polycarbonates, polystyrenes, polyesters, polyamides, polyamideimides, polyarylates, polyarylsulfones, polyethersulfones, polyphenylene sulfides, polyvinyl chlorides, polysulfones, polyimides, polyetherimides, polytetrafluoroethylenes, polyetherketones, polyether etherketones, polyether ketone ketones, polybenzoxazoles, polyoxadiazoles, polybenzothiazinophenothiazines, polybenzothiazoles, polypyrazinoquinoxalines, polypyromellitimides, polyquinoxalines, polybenzimidazoles, polyoxindoles, polyoxoisoindolines, polydioxoisoindolines, polytriazines, polypyridazines, polypiperazines, polypyridines, polypiperidines, polytriazoles, polypyrazoles, polypyrrolidines, polycarboranes, polyoxabicyclononanes, polydibenzofurans, polyphthalides, polyacetals, polyanhydrides, polyvinyl ethers, polyvinyl thioethers, polyvinyl alcohols, polyvinyl ketones, polyvinyl halides, polyvinyl nitriles, polyvinyl esters, polysulfonates, polysulfides, polythioesters, polysulfones, polysulfonamides, polyureas, polyphosphazenes, polysilazanes, or the like, or a combination including at least one of the foregoing plastic resins.
[0035] Specific non-limiting examples of blends of thermoplastic resins include acrylonitrile-butadiene-styrene/nylon, polycarbonate/acrylonitrile-butadiene-styrene, polyphenylene ether/polystyrene, polyphenylene ether/polyamide, polycarbonate/polyester, polyphenylene ether/polyolefin, and combinations including at least one of the foregoing blends of thermoplastic resins.
[0036] Examples of thermosetting resins include polyurethane, natural rubber, synthetic rubber, epoxy, phenolic, polyesters, polyamides, silicones, and mixtures including any one of the foregoing thermosetting resins. Blends of thermoset resins as well as blends of thermoplastic resins with thermosets can be utilized.
[0037] The specific resin used for the RFID article may vary depending on the selected characteristics of the final RFID article. Factors that may be used to select the plastic resin include, but are not limited to, the final use for the RFID article, the conditions (temperature, humidity, pressure, etc.) in which the RFID article will be utilized, the selected size and/or shape of the RFID article. In one embodiment, the plastic housing is formed using a plastic resin that is different from the plastic resin used for the seal. In another embodiment, the plastic housing is formed using a plastic resin that is the same as the plastic resin used for the seal.
[0038] The RFID articles may be constructed using any conventional molding process used for plastic resins. In one embodiment, the housing of the RFID article may be constructed using an injection molding process, a thermoforming process, or any other molding process capable of forming a formed shape plastic article. In another embodiment, the seal is formed using an overmolding process capable of forming a seal using a plastic resin. In one embodiment, the overmolding process is a lamination process. In another embodiment, the overmolding process is an injection molding step wherein the plastic resin for the seal in injected around the housing.
[0039] As discussed, the RFID article has enhanced break strength and/or temperature resistance. As used herein, “enhanced break strength” refers to the tensile force required to get the sheaths/envelops covering the RFID separated through the failure of sheath material or bonding surface or both, thus exposing the encapsulated RFID to the outer environment/atmosphere. In one embodiment of the present invention, the RFID article shows a bond strength of 1000N or greater as measured using numerical simulation technique. In another embodiment of the present invention, the RFID article shows a bond strength of 1200N or greater as measured using numerical simulation technique. In yet another embodiment of the present invention, the RFID article shows a bond strength of 1300N or greater as measured using numerical simulation technique. This is as compared to a standard laundry tag that shows a bond strength of about 200N as measured using numerical simulation technique. In order to compare the current concept with the prior art design, the same geometric configuration was considered and both were subjected to the same tensile load, and their resulting performance were critically studied through the well established computer aided engineering and simulation methodologies. As used herein, an RFID article having “enhanced thermal resistance” refers to an RFID article that, in one embodiment, has a better weathering at elevated temperatures and better barrier properties due to the higher contact area, which results in better performance in an autoclave cycle.
[0040] The foregoing and other features of the present invention will be more readily apparent from the following detailed description and drawing of one illustrative embodiment of the invention.
[0041] Referring to the drawings, FIGS. 1-4 provide one embodiment of an RFID article wherein a one-piece housing or substrate is used. In this embodiment, a first substrate material 102 is provided. The RFID tag 104 is placed on the substrate 102 . In an alternative embodiment, the RFID tag 104 is a circuit that is printed into the substrate 102 . After the RFID tag 104 has been placed on the substrate 102 , the seal layer is provided. In this embodiment, the seal comprises two barrier film layers 106 that are overmolded on either side of the substrate using a lamination process. Due to the lamination and the choice of materials for the barrier layers 106 and the substrate 102 , the three layers can be fused together, thereby eliminating or substantially eliminating any seams. As a result, the resulting RFID tag has enhanced thermal resistance. In addition, depending on the selected characteristics, if greater break strength is desired, the substrate and/or barrier layers may be selected using plastic materials having enhanced physical properties and/or by using thicker layers. Conversely, if a thinner RFID article is desired, thinner layers may be used. However, despite the thinner layers, the resulting RFID article will still have enhanced thermal resistance.
[0042] FIGS. 5-7 provide an alternative embodiment of an RFID article 200 wherein a two-piece housing or substrate is used. In this embodiment, a substrate 202 is thermoformed such that the substrate 202 is cup-shaped. The RFID tag 204 is placed within the cup portion of the substrate 202 . In this embodiment, placement of the RFID tag 204 can be automated using index holes 206 that enable the proper placement of the RFID tag 204 . Once the RFID tag 204 has been placed, a cover layer 208 is placed over the substrate 202 to hold the RFID tag 204 in place and to form the two-piece housing. Then, as seen in FIG. 7 , the encapsulated RFID tag 204 may be placed in a molding cavity 210 wherein the overmolded seal material 212 is then introduced to seal the RFID tag 204 and form an RFID article 200 having enhanced break strength and/or thermal resistance.
[0043] FIGS. 8-10 show an alternative embodiment for an RFID article 300 using a two-piece housing. In this embodiment, the housing 302 includes a first cover 304 and a second cover 306 wherein, when joined together, the resulting housing 302 includes a cavity 308 into which an RFID tag 310 , including an antenna 311 , may be placed. In this embodiment, the first cover 304 and second cover 306 are formed from a plastic material, which may be the same or different materials, and may be joined using any conventional means for joining two plastic parts to one another, including the use of mechanical locking mechanisms or melting or welding the parts to one another, or through the use of chemical means, such as adhesive materials.
[0044] Once the RFID tag 310 has been located within the housing 302 and the first cover 304 and second cover 306 have been joined to one another, a sealing material 312 is overmolded around the housing 302 to cover the seams or seal 314 between the first cover 304 and the second cover 306 . By covering or encasing the seams 314 , the resulting RFID article 300 has enhanced break strength and/or thermal resistance. As seen in FIG. 10 , in one embodiment, the sealing material 312 helps improve thermal resistance by covering the seams/seals 314 and increasing the path any moisture must traverse to contact the RFID tag 310 . In addition, the housing 302 can be shaped such that the sealing material 312 acts as a positive lock 316 of the first and second covers 304 , 306 to help hold the covers together, thereby increasing the break strength of the article 300 .
[0045] FIGS. 11-12 show an alternative embodiment of the seal material 312 and how the seal material 312 may be used to form an RFID article 300 having enhanced break strength and/or thermal resistance. In this embodiment, the sealing material is in the form of a sealing ring 314 that includes a plurality of rivets 318 that help secure the sealing ring 316 to the housing 302 via a plurality of holes 320 in the housing. As the cross sectional view shows, the rivets 318 are offset at the top and bottom to help form a positive lock to help secure the first and second covers 304 , 306 to one another. Also, as may be seen, in this embodiment, the sealing material 312 does not encase the housing 302 , but still provides enhanced thermal resistance by lengthening the path any moisture must traverse to reach the interior of the housing 302 and the RFID tag 310 .
[0046] It should also be apparent to those skilled in the art that the concepts of the present invention can not only be used to provide RFID articles that may be used in sterilization environments, but also in other applications including, but not limited to, auto immobilizers, transportation/ticketing applications, supply chain management applications, animal identification devices, RTLS (Real Time Location Systems), security and/or access control applications, toll collections, asset tracking applications, passports/driver's licenses, rental items, baggage tags and the like. In case of sensors it can also be used for crash sensors, accelerometer, strain gauges, pressure transducers, and data acquisition systems. And any article that needs to be encapsulated like outdoor antennas, miniature cameras, archeological preservation.
[0047] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. 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 languages of the claims. All citations referred herein are expressly incorporated herein by reference.
|
Encapsulated radio frequency identification (RFID) articles having enhanced break strength and/or temperature resistance and methods of making these articles. The RFID articles include an RFID tag embedded within a thermoplastic substrate to form the RFID article. In one embodiment, the RFID article includes an over-molded barrier material that enables the RFID article to have enhanced temperature resistance such that the articles are able to sustain repeated exposure to high temperatures and/or sterilization procedures, thereby enabling the RFID articles to be utilized in applications heretofore unavailable. In other embodiments, the RFID articles are made using an injection molding process that provides very thin encapsulated RFID tags that also exhibit an increased level of temperature resistance.
| 6
|
CROSS REFERENCE TO RELATED APPLICATION
Cross reference is made to concurrently filed U.S. patent application Ser. No. 12/000,617 and titled “Organic Light Emitting Display and Driving Circuit Thereof.”
BACKGROUND OF THE INVENTION
1. Field of the Invention
Embodiments of the present invention relate to a light emitting display, e.g., an organic light emitting display, and a driving circuit thereof. More particularly, embodiments of the invention relate to light emitting displays and driving circuits thereof in which a single light emitting control driving line is electrically coupled to multiple, e.g., two, rows of pixels of a display and is capable of simultaneously supplying a light emitting control signal to the multiple, e.g., two, rows of pixels simultaneously and/or substantially simultaneously, i.e., is capable of respectively supplying a light emitting control signal to the multiple, e.g., two, rows of pixels during a same driving period in order to reduce a number of driving circuits, reduce manufacturing cost, and improve yield.
2. Description of the Related Art
In general, an organic light emitting display is a display device that is capable of electrically exciting a light emitting material, e.g., a fluorescent or phosphorescent organic compound, to emit light and display an image by driving N×M organic light emitting diodes (OLEDs). An OLED may include an anode, e.g., indium tin oxide (ITO), an organic thin film, and a cathode, e.g., metal. The organic thin film may include multi-layers, e.g., an emitting layer (EML) in which light is emitted when electrons are combined with holes, an electron transport layer (ETL) in which the electrons are transported, and a hole transport layer (HTL) in which the holes are transported. The organic thin film may further include an electron injecting layer (EIL) in which additional electrons are injected and a hole injecting layer (HIL) in which holes are injected.
Such OLEDs may be driven using a passive matrix method and/or an active matrix method in which an MOS (metal oxide silicon) thin film transistor (TFT) may be used. In the passive matrix method, an anode and a cathode, which extend perpendicular to each other, may be used to select and drive a line. In the active matrix method, each of the TFTs and a capacitor is connected to an ITO pixel electrode to store a voltage using the capacitance of the capacitor.
Such organic light emitting displays may be used as a display device for a variety of devices, e.g., a personal computer, a mobile phone, a portable information terminal, such as a PDA, or a display device for a plurality of information equipment.
A plurality of light emitting display devices that have a relatively lighter-weight and smaller size than cathode ray tube displays have been developed. For example, organic light emitting displays have been developed. The organic light emitting displays also have relatively excellent luminous efficiency, brightness, wide-viewing angle, and fast response speed.
However, as the resolution of the organic light emitting displays increases, the size of a driving unit used to drive the pixels thereof becomes large. To help reduce the size of the organic light emitting display, a dead space is used for the driving unit thereof. However, the amount of dead space of a real product, e.g., an organic light emitting display, is limited. If the size of the driving unit for driving the relatively higher-resolution organic light emitting display becomes larger than the size of the limited dead space, the size of the organic light emitting display increases. Accordingly, there is a problem in that the size of the organic light emitting display may be increased as a result of, e.g., the relatively large size of the driving unit.
Further, many light emitting control driving circuits include both an PMOS transistor(s) and an NMOS transistor(s). Such light emitting control drivers thus require an additional processing step(s) and/or substrate. Accordingly, there is a problem in that the organic light emitting display may become relatively large and heavy, and the processing thereof may become complicated.
SUMMARY OF THE INVENTION
The present invention is therefore directed to providing a light emitting display and a driving circuit thereof that substantially overcome one or more of the problems due to the limitations and disadvantages of the related art.
It is therefore a feature of an embodiment of the present invention to provide a light emitting display, e.g., an organic light emitting display, and a driving circuit thereof in which one light emitting control driving line is electrically coupled to a plurality of, e.g., two, rows of pixels such that a same/single light emitting control signal may be supplied to the respective plurality of, e.g., two, rows of pixels associated therewith during a same driving period, i.e., may be simultaneously and/or substantially simultaneously supplied to the respective plurality of, e.g., two, rows of pixels associated therewith.
It is therefore a separate feature of an embodiment of the present invention to provide a light emitting control driver and a light emitting display, e.g., an organic light emitting display, including such a light emitting control driver that is electrically coupled to a plurality of, e.g., two, rows of pixels and is adapted to simultaneously and/or substantially simultaneously supply a light emitting control signal to the respective plurality of, e.g., two, rows of pixels such that an area of the driving circuit and/or a manufacturing cost may be reduced, and a manufacturing yield thereof may be increased. That is, the light emitting control driver may respectively supply a same single light emitting control signal to each of the plurality of rows of pixels during a same driving period.
It is therefore a separate feature of an embodiment of the present invention to provide a light emitting control driver including only transistors of a same transistor-type that are included in pixels of a light emitting display.
It is therefore a separate feature of an embodiment of the present invention to provide a light emitting control driver and/or a light emitting display, e.g., an organic light emitting display, including such a light emitting control driver having a relatively lower manufacturing cost, a relatively shorter manufacturing time, and/or an improved manufacturing yield.
At least one of the above and other features and advantages of the present invention may be realized by providing an organic light emitting display, including a first light emitting control driver electrically coupled to an initial driving line, a first clock line, and a first negative clock line, and adapted to output a first light emitting control signal via a first light emitting control line, and a first light emitting negative control signal via a first light emitting negative control line, a first pixel unit electrically coupled to the first light emitting control line, a second pixel unit electrically coupled to the first light emitting control line, a second light emitting control driver electrically coupled to the first light emitting negative control line, a second clock line, and a second negative clock line, and adapted to output a second light emitting control signal via a second light emitting control line, and a second light emitting negative control signal via a second light emitting negative control line, a third pixel unit electrically coupled to the second light emitting control line, and a fourth pixel unit electrically coupled to the second light emitting control line.
A first clock terminal of the first light emitting control driver may be electrically coupled to the first clock line, a second clock terminal of the first light emitting control driver may be electrically coupled to the negative clock line, an input terminal of the first light emitting control driver may be electrically coupled to the initial driving line, an output terminal of the first light emitting control driver may be electrically coupled to the first light emitting control line for outputting the first light emitting control signal, and a negative output terminal of the first light emitting control driver may be electrically coupled to the first light emitting negative control line for outputting the first light emitting negative control signal.
A first clock terminal of the second light emitting control driver may be electrically coupled to the second clock line, a second clock terminal of the second light emitting control driver may be electrically coupled to the second negative clock line, an input terminal of the second light emitting control driver may be electrically coupled to the first light emitting negative control line, an output terminal of the second light emitting control driver may be electrically coupled to the second light emitting control line for outputting the second light emitting control signal, and a negative output terminal of the second light emitting control driver may be electrically coupled to the second light emitting negative control line for outputting the second light emitting negative control signal.
The first pixel unit may include pixels of a first row of a panel that are electrically coupled between a first scanning driving line and first to m-th data lines. The second pixel unit may include pixels of a second row of a panel that are electrically coupled between a second scanning driving line and first to m-th data lines. The third pixel unit may include pixels of a third row of a panel that are electrically coupled between a third scanning driving line and first data line to m-th data lines.
The fourth pixel unit may include pixels of a fourth row of a panel that are electrically coupled between a fourth scanning driving line and first data line to m-th data lines. The first pixel unit and the second pixel unit may emit light based on the first light emitting control signal. The third pixel unit and the fourth circuit unit may emit light based on the second light emitting control signal.
At least one of the above and other features and advantages of the present invention may be separately realized by providing a driving circuit including a plurality of light emitting control drivers, including an input terminal coupled to an initial driving line or a light emitting negative control line of a previous light emitting control driver, a first clock terminal and a second clock terminal that are electrically coupled to a first clock line and a first negative clock line that are phase-inverted, or a second clock line and a second negative clock line, respectively, and an output terminal and a negative output terminal adapted to generate an output signal and a negative output signal when receiving an input signal, a clock signal and a negative clock signal via the input terminal, the first clock terminal and the second clock terminal, respectively.
The clock signal may be a signal transferred from the first clock line or the second clock line. The negative clock signal may be a signal transferred from the first negative clock line or the second negative clock line.
Each of the light emitting control drivers may include a first switching element electrically coupled between the input terminal and a first power supply line, a second switching element that includes a control electrode electrically coupled to the first clock terminal, and is electrically coupled between the first switching element and the first power supply line, a third switching element that includes a control electrode electrically coupled between the first switching element and the second switching element, and is electrically coupled between the second switching element and the second clock terminal, a fourth switching element that includes a control electrode electrically coupled between the second switching element and the third switching element, and is electrically coupled between the first power supply line and a second power supply line, a fifth switching element that includes a control electrode electrically coupled to the first clock terminal, and is electrically coupled between the fourth switching element and the second power supply line, a sixth switching element that includes a control electrode electrically coupled between the fourth switching element and the fifth switching element, and is electrically coupled between the first power supply line and a second power supply line, a seventh switching element that includes a control electrode electrically coupled between the second switching element and the third switching element, and is electrically coupled between the sixth switching element and the second power supply line, an eighth switching element that includes a control electrode electrically coupled between the sixth switching element and the seventh switching element, and is electrically coupled between the first power supply line and a second power supply line, and a ninth switching element that includes a control electrode electrically coupled between the fourth switching element and the fifth switching element, and is electrically coupled between the eighth switching element and the second power supply line.
The first clock terminal of a first light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the first clock line, the second clock terminal of the first light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the first negative clock line, the input terminal of the first light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the initial driving line, the output terminal of the first light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the first light emitting control line for outputting the first light emitting control signal, and the negative output terminal of the first light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the first light emitting negative control line for outputting the first light emitting negative control signal.
The first clock terminal of a second light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the second clock line, the second clock terminal of the second light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the second negative clock line, the input terminal of the second light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the first light emitting negative control signal, the output terminal of the second light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the second light emitting control line for outputting the second light emitting control signal, and the negative output terminal of the second light emitting control driver of the plurality of light emitting control drivers may be electrically coupled to the second light emitting negative control line for outputting the second light emitting negative control signal.
In odd-numbered ones of the plurality of light emitting control drivers, except for a first one of the plurality of light emitting control drivers, the first clock terminal may be electrically coupled to the first clock line or the first negative clock line, the second clock terminal is electrically coupled to the first negative clock line or the first clock line, the input terminal may be electrically coupled to the light emitting negative control line of the previous light emitting control driver, the output terminal may be electrically coupled to an odd-numbered light emitting control line for outputting the light emitting control signal, and the negative output terminal may be electrically coupled to the odd-numbered light emitting control line for outputting the light emitting negative control signal.
The first clock terminal of the respective odd-numbered light emitting control drivers may be electrically coupled to the first clock line when the second clock terminal is electrically coupled to the first negative clock line, and the second clock terminal may be electrically coupled to the first clock line when the first clock terminal is electrically coupled to the first negative clock line.
In even-numbered ones of light emitting control drivers, the first clock terminal may be electrically coupled to the second clock line or the second negative clock line, the second clock terminal may be electrically coupled to the second negative clock line or the second clock line, the input terminal may be electrically coupled to the light emitting negative control line of the previous light emitting control driver, the output terminal may be electrically coupled to the even-numbered light emitting control line for outputting the light emitting control signal, and the negative output terminal may be electrically coupled to the even-numbered light emitting control line for outputting the light emitting negative control signal.
In the even-numbered light emitting control drivers, when the first clock terminal is electrically coupled to the second clock line, the second clock terminal may be electrically coupled to the second negative clock line, and when the second clock terminal is electrically coupled to the second clock line, the first clock terminal may be electrically coupled to the second negative clock line.
The control electrode of the first switching element may be electrically coupled to the input terminal, a first electrode thereof may be electrically coupled to the control electrode of the third switching element, and a second electrode thereof may be electrically coupled to the input terminal. The control electrode of the first switching element may be electrically coupled to the first clock terminal, a first electrode thereof may be electrically coupled to the control electrode of the third switching element, and a second electrode thereof may be electrically coupled to the input terminal. The second switching element may include a first electrode electrically coupled to the first power supply line, and a second electrode electrically coupled between the control electrode of the third switching element and the control electrode of the fourth switching element.
The third switching element may include a first electrode electrically coupled between the control electrode of the fourth switching element and the control electrode of the seventh switching element, and a second electrode electrically coupled to the second clock terminal. The fourth switching element may include a first electrode electrically coupled to the first power supply line, and a second electrode electrically coupled between the first electrode of the fifth switching element and the control electrode of the sixth switching element the fifth switching element may include a first electrode electrically coupled between the control electrode of the sixth switching element and the control electrode of the ninth switching element, and a second electrode electrically coupled to the second power supply line. The sixth switching element may include a first electrode electrically coupled to the first power supply line, and a second electrode electrically coupled between the first electrode of the seventh switching element and the control electrode of the eighth switching element.
The seventh switching element may include a first electrode electrically coupled between the control electrode of the eighth switching element and the first light emitting negative control line, and a second electrode electrically coupled to the second power supply line. The eighth switching element may include a first electrode electrically coupled to the first power supply line, and a second electrode electrically coupled to the first light emitting control line.
The ninth switching element may include a first electrode electrically coupled to the first light emitting control line, and a second electrode electrically coupled to the second power supply line.
The driving circuit may include a first storage capacitor including a first electrode electrically coupled to the control electrode of the third switching element and a second electrode electrically coupled between the second switching element and the third switching element. The driving circuit may include a second storage capacitor including a first electrode electrically coupled between the control electrode of the ninth switching element and the control electrode of the sixth switching element, and a second electrode electrically coupled between the eighth switching element, the ninth switching element, and the first power supply line. An organic light emitting display may include such a driving circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the attached drawings, in which:
FIG. 1 illustrates a block diagram of an organic light emitting display according to an exemplary embodiment of the invention;
FIG. 2 illustrates a block diagram of an exemplary embodiment of a light emitting control driver employable by the organic light emitting display shown in FIG. 1 ;
FIG. 3 illustrates a circuit diagram of a light emitting control driving circuit employable by the light emitting control driver shown in FIG. 2 ;
FIG. 4 illustrates a timing diagram of exemplary signals employable for driving the light emitting control driving circuit shown in FIG. 3 ;
FIG. 5 illustrates a circuit diagram of an operating state of the light emitting control driving circuit shown in FIG. 3 during a first driving period;
FIG. 6 illustrates a circuit diagram of an operating state of the light emitting control driving circuit shown in FIG. 3 during a second driving period;
FIG. 7 illustrates a circuit diagram of an operating state of the light emitting control driving circuit shown in FIG. 3 during a third driving period;
FIG. 8 illustrates a circuit diagram of another exemplary embodiment of a light emitting control driving circuit employable by the light emitting control driver shown in FIG. 2 ;
FIG. 9 illustrates a timing diagram of exemplary signals employable for driving the light emitting control driving circuit shown in FIG. 8 ; and illustrates a timing diagram of exemplary signals employable for driving the light emitting control driving circuit shown in FIG. 8 ; and
FIG. 10 illustrates a timing diagram of exemplary signals employable for driving the light emitting control driver shown in FIG. 2 .
DETAILED DESCRIPTION OF THE INVENTION
Korean Patent Application No. 10-2007-0020737, filed on Mar. 2, 2007, in the Korean Intellectual Property Office, and entitled: “Organic Light Emitting Display and Driving Circuit Thereof,” is incorporated by reference herein in its entirety.
Aspects of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are illustrated. Aspects of the invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
Throughout the specification, like reference numerals refer to like elements having similar structures or operations throughout the specification. Further, it will be understood that when one part is described as being electrically coupled to another part, the two parts may be directly connected to each other or may be indirectly connected via other elements positioned or connected therebetween.
FIG. 1 illustrates a block diagram of an organic light emitting display 100 according to an exemplary embodiment of the invention.
As shown in FIG. 1 , the organic light emitting display 100 may include a scan driver 110 , a data driver 120 , a light emitting control driver 130 , and an organic light emitting display panel (hereinafter, referred to as panel 140 ).
The panel 140 may include a plurality of scan lines (Scan[ 1 ], Scan[ 2 ], . . . , Scan[n]) and a plurality of light emitting control lines (Em[ 1 ], Em[ 2 ], . . . , Em[n/ 2 ]) arranged in a row direction, a plurality of data lines (Data[ 1 ], Data[ 2 ], . . . , Data[m]) arranged in a column direction, and a plurality of pixels 141 defined by the plurality of scan lines (Scan[ 1 ], Scan[ 2 ], . . . , Scan[n]), the plurality of data lines (Data[ 1 ], Data[ 2 ], . . . , Data[m]), and the plurality of light emitting control lines (Em[ 1 ], Em[ 2 ], . . . , Em[n/ 2 ]).
The pixels 141 may be formed in pixel regions defined by respective ones of two adjacent scan lines (Scan[ 1 ], Scan[ 2 ], . . . , Scan[n]) and two adjacent ones of the data lines (Data[ 1 ], Data[ 2 ], . . . , Data[m]).
The scan driver 110 may sequentially supply respective scan signals to the panel 140 through the plurality of scan lines (Scan[ 1 ], Scan[ 2 ], . . . , Scan[n]).
The data driver 120 may sequentially supply respective data signals to the panel 140 through the plurality of data lines (Data[ 1 ], Data[ 2 ], . . . , Data[m]).
The light emitting control driver 130 may sequentially supply light emitting control signals to the panel 140 through the plurality of light emitting control lines (Em[ 1 ], Em[ 2 ], . . . , Em[n/ 2 ]). The plurality of pixels 141 may be connected to the light emitting control lines (Em[ 1 ], Em[ 2 ], . . . , Em[n/ 2 ]) and may receive the respective light emitting control signals to determine a point of time at which current generated in respective ones of the pixels 141 flows to respective light emitting diode thereof. The pixels 141 may be electrically coupled between the light emitting control lines (Em[ 1 ], Em[ 2 ], . . . , Em[n/ 2 ]) and the scan lines (Scan[ 1 ], Scan[ 2 ], . . . , Scan[n]). Each of the light emitting control lines (Em[ 1 ], Em[ 2 ], . . . , Em[n/ 2 ]) may be electrically coupled to a plurality of, e.g., two, rows of pixels to simultaneously transfer the respective light emitting signal to the corresponding pixels 141 in the plurality of, e.g., two, rows of pixels associated therewith.
In the description of exemplary embodiments herein, each of the light emitting control lines (Em[ 1 ], Em[ 2 ], . . . , Em[n/ 2 ]) will be described as being connected to two rows of the pixels. Further, in the following description of exemplary embodiments a predetermined group, e.g., a row, of the pixels 141 may be referred to as a pixel unit. However, embodiments of the invention are not limited thereto.
In some embodiments of the invention, e.g., a first light emitting control line (Em[ 1 ]) may be electrically coupled to the pixels 141 of first and second pixel units PS_ 1 , PS_ 2 (see FIG. 2 ) that may be electrically coupled to the first and second scan lines (Scan[ 1 ], Scan[ 2 ]) to simultaneously transfer the first light emitting control signal to the pixels 141 of the first and second pixel units PS_ 1 , PS_ 2 . By electrically coupling each of the light emitting control lines (Em[ 1 ], Em[ 2 ], . . . , Em[n/ 2 ]) to two of the scan lines (Scan[ 1 ], Scan[ 2 ], . . . , Scan[n]), the size of the light emitting control driver 130 according to embodiments of the invention may be reduced to, e.g., one-half of a light emitting control driver having, e.g., a separately driven light emitting control line electrically coupled to each of the scan lines, i.e., a separate light emitting control driving unit for each of the light emitting control lines and each of the scan lines.
Further, the light emitting control driver 130 according to embodiments of the invention may be implemented using transistors of only a same kind as transistors of the pixels 141 such that the light emitting control driver 130 may be formed on a same substrate without additional processing when forming the panel 140 of the light emitting display. Therefore, embodiments of the invention may enable the light emitting control driver 130 to be formed on the same substrate as the pixels 141 without requiring additional processing and/or an additional chip.
FIG. 2 illustrates a block diagram of an exemplary embodiment of the light emitting control driver 130 employable by the organic light emitting display shown in FIG. 1 . As illustrated in FIG. 2 , the light emitting control driver 130 may include first to n/ 2 light emitting control driving units (Emission_ 1 to Emission_n/ 2 ). The first to the n/ 2 light emitting control driving units (Emission_ 1 to Emission_n/ 2 ) may be electrically coupled to first to nth pixel units (PS_ 1 to PS_n) to apply a respective light emitting control signal to each of the pixel units (PS_ 1 , PS_ 2 , . . . ,PS_n). More particularly, in embodiments of the invention, each of the n pixel units (PS_ 1 , PS_ 2 , . . . PS_n) may be electrically coupled to a respective one of the n/ 2 light emitting control driving units (Emission_ 1 , Emission_ 2 , . . . , Emission_n/ 2 ), where n may be any positive integer, and multiple ones, e.g., two, of the n pixel units (PS_ 1 , PS_ 2 , . . . PS_n) may be coupled to each of the light emitting control driving units (Emission_ 1 to Emission_n/ 2 ). Thus, embodiments of the invention may enable a size of a light emitting control driver to be reduced to, e.g., one half of a light emitting control driver in which only one pixel unit is electrically coupled to each light emitting control driving unit thereof.
The first light emitting control driving unit (Emission_ 1 ) may include a first clock terminal (clka) electrically coupled to a first clock line (CLK 1 ), a second clock terminal (clkb) electrically coupled to a first negative clock line (CLKB 1 ), an input terminal (In) electrically coupled to an initial driving line (Sp), an output terminal (Out) and a negative output terminal (OutB). The input terminal (In) may receive an initial driving signal. The first light emitting control driving unit (Emission_ 1 ) may output a first light emitting control signal to a first light emitting control line (Em[ 1 ]), which may be electrically coupled to the output terminal (Out) thereof. The first light emitting control driving unit (Emission_ 1 ) may also output a first light emitting negative control signal to a first light emitting negative control line (EmB[ 1 ]), which may be electrically coupled to the negative output terminal (OutB) thereof.
In some embodiments of the invention, the first light emitting control driving unit (Emission_ 1 ) may be electrically coupled to the first pixel unit (PS_ 1 ) and the second pixel unit (PS_ 2 ), and may apply the first light emitting control signal to the first pixel unit (PS_ 1 ) and the second pixel unit (PS_ 2 ) respectively. More particularly, the first light emitting control line (Em[ 1 ]) may be electrically coupled to the first pixel unit (PS_ 1 ) and the second pixel unit (PS_ 2 ), and the first light emitting control driving unit (Emission_ 1 ) may apply the first light emitting control signal to the first pixel unit (PS_ 1 ) and the second pixel unit (PS_ 2 ) simultaneously, e.g., respectively during a same driving period.
The second light emitting control driving unit (Emission_ 2 ) may include a first clock terminal (clka) electrically coupled to a second clock line (CLK 2 ), a second clock terminal (clkb) electrically coupled to a second negative clock line (CLKB 2 ), an input terminal (In), an output terminal (Out) and a negative output terminal (OutB). The input terminal (In) thereof may be electrically coupled to the first light emitting negative control line (EmB[ 1 ]), and may receive the first light emitting negative control signal. The second light emitting control driving unit (Emission_ 2 ) may output a second light emitting control signal to a second light emitting control line (Em[ 2 ]), which may be electrically coupled to the output terminal (Out) thereof and may output a second light emitting negative control signal to a second light emitting negative control line (EmB[ 2 ]), which may be electrically coupled to the negative output terminal (OutB) thereof.
In some embodiments of the invention, the second light emitting control driver (Emission_ 2 ) may be electrically coupled to a third pixel unit (PS_ 3 ) and a fourth pixel unit (PS_ 4 ) via the second light emitting control line (Em[ 2 ]), and may apply the second light emitting control signal to the third pixel unit (PS_ 3 ) and the fourth pixel unit (PS_ 4 ) respectively. More particularly, the second light emitting control driving unit (Emission_ 2 ) may apply the second light emitting control signal to the third pixel unit (PS_ 3 ) and the fourth pixel unit (PS_ 4 ) simultaneously, e.g., respectively during a same driving period.
The third light emitting control driver (Emission_ 3 ) may include a first clock terminal (clka) electrically coupled to the first negative clock line (CLKB 1 ), a second clock terminal (clkb) electrically coupled to the first clock line (CLK 1 ), an input terminal (In), an output terminal (Out) and a negative output terminal (OutB). The input terminal (In) thereof may be electrically coupled to the second light emitting negative control line (EmB[ 2 ]) and may receive the second light emitting negative control signal. The third light emitting control driving unit (Emission_ 3 ) may output a third light emitting control signal to a third light emitting control line (Em[ 3 ]), which may be electrically coupled to the output terminal (Out) thereof and may output a third light emitting negative control signal to a third light emitting negative control line (EmB[ 3 ]), which may be electrically coupled to the negative output terminal (OutB) thereof.
In some embodiments of the invention, the third light emitting control driving unit (Emission_ 3 ) may be electrically coupled to the fifth pixel unit (PS_ 5 ) and the sixth pixel unit (PS_ 6 ) via the third light emitting control line (Em[ 3 ]). The third light emitting control driving unit (Emission_ 3 ) may apply the third light emitting control signal to the fifth pixel unit (PS_ 5 ) and the sixth pixel unit (PS_ 6 ) respectively. More particularly, the third light emitting control driving unit (Emission_ 3 ) may apply the third light emitting control signal to the fifth pixel unit (PS_ 5 ) and the sixth pixel unit (PS_ 6 ) simultaneously, e.g., respectively during a same driving period.
The fourth light emitting control driving unit (Emission_ 4 ) may include a first clock terminal (clka) electrically coupled to the second negative clock line (CLKB 2 ), a second clock terminal (clkb) electrically coupled to the second clock line (CLK 2 ), and input terminal (In), an output terminal (Out) and a negative output terminal (OutB). The input terminal (In) may be electrically coupled to the third light emitting negative control line (EmB[ 3 ]) and may receive the third light emitting negative control signal. The fourth light emitting control driving unit (Emission_ 4 ) may output a fourth light emitting control signal to a fourth light emitting control line (Em[ 4 ]), which may be electrically coupled to the output terminal (Out) thereof. The fourth light emitting control driving unit (Emission_ 4 ) may output a fourth light emitting negative control signal to the fourth light emitting negative control line (EmB[ 4 ]), which may be electrically coupled to the negative output terminal (OutB) thereof.
In some embodiments of the invention, the fourth light emitting control driving unit (Emission_ 4 ) may be electrically coupled to a seventh pixel unit (PS_ 7 ) and an eighth pixel unit (PS_ 8 ), and may apply the fourth light emitting control signal to the seventh pixel unit (PS_ 7 ) and the eighth pixel unit (PS_ 8 ) respectively. More particularly, the fourth light emitting control driving unit (Emission_ 4 ) may apply the fourth light emitting control signal to the seventh pixel unit (PS_ 7 ) and the eight pixel unit (PS_ 8 ) simultaneously, e.g., respectively during a same driving period.
In some embodiments of the invention, the light emitting control driving units (Emission_ 1 to Emission_n/ 2 ) may be coupled with the pixel units (PS_ 1 to PS_n) in a pattern following the coupling scheme described above with regard to the first, second, third and fourth light emitting control driving units (Emission_ 1 , Emission_ 2 , Emission_ 3 and Emission_ 4 ).
More particularly, e.g., in some embodiments of the invention, in the odd-numbered light emitting control driving units (Emission_ 1 , Emission_ 3 , Emission_ 5 , etc.), first and second clock terminals (clka, clkb) thereof may be alternately coupled to the first clock line (CLK 1 ) and the first negative clock line (CLKB 1 ). That is, e.g., if the first and second clock terminals (clka, clkb) of the fifth light emitting control driving unit (Emission_ 5 ) are respectively electrically coupled to the first clock line (CLK 1 ) and the first negative clock line (CLKB 1 ) thereof, the first and second clock terminals (clka, clkb) of the seventh (e.g., subsequent odd-numbered) light emitting control driving unit (Emission_ 7 ) may be respectively electrically coupled to the first negative clock line (CLKB 1 ) and the first clock line (CLK 1 ) thereof.
More particularly, e.g., in some embodiments of the invention, in the even-numbered light emitting control driving units (Emission_ 2 , Emission_ 4 , Emission_ 6 , etc.) first and second clock terminals (clka, clkb) thereof may be alternately coupled to the second clock line (CLK 2 ) and the first negative clock line (CLKB 2 ). That is, e.g., if the first and second clock terminals (clka, clkb) of the sixth light emitting control driving unit (Emission_ 6 ) are respectively electrically coupled to the second clock line (CLK 2 ) and the second negative clock line (CLKB 2 ) thereof, the first and second clock terminals (clka, clkb) of the eighth (e.g., subsequent even-numbered) light emitting control driving unit (Emission_ 8 ) may be respectively electrically coupled to the second negative clock line (CLKB 2 ) and the second clock line (CLK 2 ) thereof.
Further, with regard to other terminals of the light emitting control driving units, the input terminal (In) thereof may be electrically coupled to the light emitting negative control line of a previous light emitting control driver, a light emitting control signal may be output via the light emitting control line electrically coupled to the output terminal (Out) thereof, and a light emitting negative control signal may be output via the light emitting negative control line of the negative output terminal (OutB) thereof.
FIG. 3 illustrates a circuit diagram of a light emitting control driving circuit 300 employable by the light emitting control driver 130 shown in FIG. 2 .
More particularly, in some embodiments of the invention, the light emitting control driving circuit 300 may be employed by each of the light emitting control driving units (Emission_ 1 , Emission_ 2 , Emission_n/ 2 ). As illustrated in FIG. 3 , the light emitting control driving circuit 300 may include a first switching element (S 1 ), a second switching element (S 2 ), a third switching element (S 3 ), a fourth switching element (S 4 ), a fifth switching element (S 5 ), a sixth switching element (S 6 ), a seventh switching element (S 7 ), an eighth switching element (S 8 ), a ninth switching element (S 9 ), a first storage capacitor (C 1 ) and a second storage capacitor (C 2 ).
The first switching element (SI) may include a first electrode (a drain electrode or a source electrode) electrically coupled to a control electrode of the third switching element (S 3 ), a second electrode (a source electrode or a drain electrode) electrically coupled to the input terminal (In) of the respective light emitting control driving unit (e.g., Emission_ 1 ), and a control electrode (gate electrode) electrically coupled to the first clock terminal (clka). When a clock signal of a low level is applied to the control electrode of the first switching element (S 1 ), the first switching element (S 1 ) is turned on and thus, a signal applied to the input terminal (In) is applied to the control electrode of the third switching element (S 3 ).
The second switching element (S 2 ) may include a first electrode electrically coupled to the first power supply line (VDD), a second electrode electrically coupled between a first electrode of the third switching element (S 3 ), a control electrode of the fourth switching element (S 4 ) and a control electrode of the seventh switching element (S 7 ), and a control electrode electrically coupled to the first clock terminal (clka). When a clock signal of a low level is applied to the control electrode of the first switching element (S 2 ), the second switching element (S 2 ) is turned on and thus, a first power voltage applied from the first power supply line (VDD) is applied to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ).
The third switching element (S 3 ) may include a first electrode electrically coupled between the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ), a second electrode electrically coupled to the second clock terminal (clkb), and a control electrode electrically coupled to the first electrode of the first switching element (S 1 ). When an input signal of a low level transmitted from the first switching element (S 1 ) is applied to the control electrode of the third switching element (S 3 ), the third switching element (S 3 ) is turned on and thus, the clock signal applied from the second clock terminal (clkb) is applied to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ).
The fourth switching element (S 4 ) may include a first electrode electrically coupled to the first power supply line (VDD), a second electrode electrically coupled between the first electrode of the fifth switching element (S 5 ), a control electrode of the sixth switching element (S 6 ) and a control electrode of the ninth switching element (S 9 ), a control electrode electrically coupled between the second switching element (S 2 ) and the third switching element (S 3 ). When an input signal of a low level, e.g., clock signal of a low level, transmitted from the third switching element (S 3 ) is applied to the control electrode of the fourth switching element (S 4 ), the fourth switching element (S 4 ) is turned on and thus, the first power voltage applied from the first power supply line (VDD) is applied to the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ).
The fifth switching element (S 5 ) may include a first electrode electrically coupled between the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ), a second electrode electrically coupled to the second power supply line (VSS), and a control electrode electrically coupled to the first clock terminal (clka). When a clock signal of a low level is applied to the control electrode of the fifth switching element (S 5 ), the fifth switching element (S 5 ) is turned on and thus, the second power voltage applied from the second power supply line (VSS) is applied to the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ).
The sixth switching element (S 6 ) may include a first electrode electrically coupled to the first power supply line (VDD), a second electrode electrically coupled between the first electrode of the seventh switching element (S 7 ), a control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB) of the respective light emitting control driving unit, e.g., (Emission_ 1 ), and a control electrode electrically coupled between the fourth switching element (S 4 ) and the fifth switching element (S 5 ). When the second power voltage transmitted from the fifth switching element (S 5 ) is applied to the control electrode of the sixth switching element (S 6 ), the sixth switching element (S 6 ) is turned on and thus, the first power voltage applied from the first power supply line (VDD) is output to the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB).
The seventh switching element (S 7 ) may include a first electrode electrically coupled between the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB) of the respective light emitting control driving unit, e.g., (Emission_ 1 ), a second electrode electrically coupled to the second power supply line (VSS), and a control electrode electrically coupled between the second switching element (S 2 ) and the third switching element (S 3 ). When a clock signal of a low level transmitted from the third switching element (S 3 ) is applied to the control electrode of the seventh switching element (S 7 ), the seventh switching element (S 7 ) is turned on and thus, the second power voltage applied from the second power supply line (VSS) is output to the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB).
The eighth switching element (S 8 ) may include a first electrode electrically coupled to the first power supply line (VDD), a second electrode electrically coupled between the first electrode of the ninth switching element (S 9 ), and the output terminal (Out) of the respective light emitting control driving unit, e.g., (Emission_ 1 ), and a control electrode electrically coupled between the sixth switching element (S 6 ) and the seventh switching element (S 7 ). When the second power voltage transmitted from the seventh switching element (S 7 ) is applied to the control electrode of the eighth switching element (S 8 ), the eighth switching element (S 8 ) is turned on and thus, the first power voltage applied from the first power supply line VDD is output to the output terminal (Out).
The ninth switching element (S 9 ) may include a first electrode electrically coupled to the output terminal (Out), a second electrode electrically coupled to the second power supply line (VSS), and a control electrode electrically coupled between the fourth switching element (S 4 ) and the fifth switching element (S 5 ). When the second power voltage transmitted from the fifth switching element (S 5 ) is applied to the control electrode of the ninth switching element (S 9 ), the ninth switching element (S 9 ) is turned on and thus, the second power voltage applied from the second power supply line (VSS) is applied to the output terminal (Out).
The first storage capacitor (C 1 ) may include a first electrode electrically coupled between the first electrode of the first switching element (S 1 ) and the control electrode of the third switching element (S 3 ), and a second electrode electrically coupled between the second switching element (S 2 ) and the third switching element (S 3 ). The first storage capacitor (C 1 ) may store a voltage difference between the first electrode and the control electrode of the third switching element (S 3 ).
The second storage capacitor (C 2 ) may include a first electrode electrically coupled to the control electrode of the ninth switching element (S 9 ), and a second electrode electrically coupled among the eighth switching element (S 8 ), the ninth switching element (S 9 ), and the output terminal (Out) of the respective light emitting control driving unit, e.g., (Emission_ 1 ). The second storage capacitor (C 2 ) may store a voltage difference between the first electrode and the control electrode of the ninth switching element (S 9 ).
As shown in FIG. 3 , all of the switching elements, e.g., S 1 , S 2 , S 3 , S 4 , S 5 , S 6 , S 7 , S 8 and S 9 , of the light emitting control driving circuits 300 of the light emitting control driving units (Emission_ 1 to Emission_n/ 2 ) may be of a same type, e.g., p-type transistors such as PMOS transistors. However, embodiments of the invention are not limited thereto as, e.g., all of the switching elements, e.g., S 1 to S 9 , may be, e.g., n-type transistors.
If the pixels 141 of the organic light emitting display include transistors of only a same type as transistors of the light emitting control driving circuits, it is possible to simplify the process of forming the organic light emitting display as the light emitting control driving circuits may be formed on a same substrate as the pixels 141 of the display without requiring additional processing. Further, if the light emitting control driving circuits 300 and the pixels 141 are formed on the same substrate, it is possible to reduce the size, weight, and cost of the organic light emitting display. Accordingly, in some embodiments in which the pixels 141 include, e.g., only p-type transistors, i.e., no n-type transistors, by structuring the light emitting control driving circuit 300 shown in FIG. 3 to include transistors of only p-type, e.g., PMOS transistors, as the first through ninth switching elements (S 1 to S 9 ), it is possible to simplify the process of forming the light emitting control driving circuits 300 and the pixels 141 and to form them on a same substrate without requiring additional processing.
FIG. 4 illustrates a timing diagram of exemplary signals employable for driving the light emitting control driving circuit 300 shown in FIG. 3 .
As shown in FIG. 4 , the timing diagram of the light emitting control driving circuit 300 shown in FIG. 3 may include a first driving period (T 51 ), a second driving period (T 52 ) and a third driving period (T 53 ). Operation of the light emitting control driving circuit 300 will be described below with reference to FIGS. 5 , 6 and 7 illustrating respective operating states of the light emitting control driving circuit 300 .
More particularly, FIG. 5 illustrates a circuit diagram of an operating state of the light emitting control driving circuit 300 shown in FIG. 3 during the first driving period (T 51 ).
During the first driving period (T 51 ), when a clock signal of a low level is applied to the first clock terminal (clka), the first switching element (S 1 ), the second switching element (S 2 ) and the fifth switching element (S 5 ) are turned on. More particularly, during the first driving period (T 51 ), the first switching element (S 1 ) may be turned on, and then, an input signal of a low level applied to the input terminal (In) may be applied to the control electrode of the third switching element (S 3 ). When the third switching element (S 3 ) receives the input signal at the low level, the third switching element (S 3 ) is turned on and supplies a clock signal at a high level supplied from a second clock terminal (clkb) to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ).
During the first driving period (T 51 ), the second switching element (S 2 ) is also turned on and applies the first power voltage of the first power supply line (VDD) to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ). As a result, the fourth switching element (S 4 ) and the seventh switching element (S 7 ) receiving the clock signal at the high level and the first power voltage of a high level are turned off. Accordingly, the first storage capacitor (C 1 ) coupled between the first electrode and the control electrode of the third switching element (S 3 ) may store a voltage corresponding to a voltage difference between the first power voltage received from the second switching element (S 2 ) and the input signal received from the first switching element (S 1 ).
Further, during the first driving period (T 51 ), the fifth switching element (S 5 ) is turned on and applies the second power voltage of the second power supply line (VSS) to the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ) such that the sixth switching element (S 6 ) and the ninth switching element (S 9 ) are turned on. When the sixth switching element (S 6 ) is turned on, the sixth switching element (S 6 ) applies the first power voltage of the first power supply line (VDD) to the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB) such that the eighth switching element (S 8 ) is turned off and the first power voltage is output through the negative output terminal (OutB). Further, the ninth switching element (S 9 ) is turned on and outputs the second power voltage of the second power supply line (VSS) to the output terminal (Out). As a result, the second storage capacitor (C 2 ) may store a voltage corresponding to the voltage difference between the second power voltage received from the fifth switching element (S 5 ) and the second power voltage received from the ninth switching element (S 9 ). The voltage stored in the second storage capacitor (C 2 ) may be used to compensate for voltage lost in the driving circuit 300 when the second power voltage is output.
FIG. 6 illustrates a circuit diagram of an operating state of the light emitting control driving circuit 300 shown in FIG. 3 during the second driving period (T 52 ).
During the second driving period (T 52 ), when a clock signal at a high level is supplied to the first clock terminal (clka), the first switching element (S 1 ), the second switching element (S 2 ), and the fifth switching element (S 5 ) are turned off. At this time, the third switching element (S 3 ) is turned on by the voltage stored in the first storage capacitor (C 1 ) during the first driving period (T 51 ) and supplies the clock signal at a low level supplied from the second clock terminal (clkb) to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ). The fourth switching element (S 4 ) and the seventh switching element (S 7 ) are turned on by receiving the clock signal at the low level. The fourth switching element (S 4 ) is turned on and applies the first power voltage of the first power supply line (VDD) to the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ) such that the sixth switching element (S 6 ) and the ninth switching element (S 9 ) are turned off.
Further, during the second driving period (T 52 ), the seventh switching element (S 7 ) is turned on and applies the second power voltage of the second power supply line (VSS) to the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB) such that the eighth switching element (S 8 ) is turned on and the second power voltage is output through the negative output terminal (OutB). Further, the eighth switching element (S 8 ) is turned on and outputs the first power voltage of the first power supply line (VDD) to the output terminal (Out). At this time, the second storage capacitor (C 2 ) may store the voltage corresponding to the voltage difference between the first power voltage received from the fourth switching element (S 4 ) and the first power voltage received from the eighth switching element (S 8 ). The voltage stored in the second storage capacitor (C 2 ) may be used to compensate for voltage lost in the driving circuit when the first power voltage is output. Since the first switching element (S 1 ) is turned off, the light emitting control driving circuit 300 operates without any change regardless of whether the input signal supplied to the input terminal (In) is at a high level or at a low level.
FIG. 7 illustrates a circuit diagram of an operating state of the light emitting control driving circuit 300 shown in FIG. 3 during the third driving period (T 53 ).
During the third driving period (T 53 ), when a clock signal at a low level is supplied to the first clock terminal (clka), the first switching element (S 1 ), the second switching element (S 2 ), and the fifth switching element (S 5 ) are turned on. The first switching element (S 1 ) is turned on and supplies an input signal at a high level transferred from the input terminal (In) to the control electrode of the third switching element (S 3 ) such that the third switching element (S 3 ) is turned off.
Further, during the third driving period (T 53 ), the second switching element (S 2 ) is turned on and applies the first power voltage of the first power supply line (VDD) to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ). The fourth switching element (S 4 ) and the seventh switching element (S 7 ) are turned off due to the first power voltage received from the second switching element (S 2 ).
Further, during the third driving period (T 53 ), the fifth switching element (S 5 ) is turned on and applies the second power voltage of the second power supply line (VSS) to the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ) such that the sixth switching element (S 6 ) and the ninth switching element (S 9 ) are turned on. When the sixth switching element (S 6 ) is turned on, the sixth switching element (S 6 ) applies the first power voltage of the first power supply line (VDD) to the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB) such that the eighth switching element (S 8 ) is turned off and the first power voltage is output through the negative output terminal (OutB). Further, the ninth switching element (S 9 ) is turned on and outputs the second power voltage of the second power supply line (VSS) to the output terminal (Out). At this time, the second storage capacitor (C 2 ) stores the voltage corresponding to the voltage difference between the second power voltage received from the fifth switching element (S 5 ) and the second power voltage received from the ninth switching element (S 9 ). The voltage stored in the second storage capacitor (C 2 ) may be used to compensate for voltage lost in the driving circuit 300 when the second power voltage is output.
FIG. 8 illustrates a circuit diagram of another exemplary embodiment of a light emitting control driving circuit 300 ′ employable by the light emitting control driver shown in FIG. 2 .
More particularly, in embodiments of the invention, the light emitting control driving circuit 300 ′ may be employed by each of the light emitting control driving units (Emission_ 1 , Emission_ 2 , Emission_n/ 2 ). In general, only differences between the first exemplary light emitting control driving circuit 300 shown in FIG. 3 and the second exemplary light emitting control driving circuit 300 ′ shown in FIG. 8 will be described below.
As shown in FIG. 8 , the light emitting control driving circuit 300 ′ may include a first switching element (S 1 ′), the second through ninth switching elements (S 2 through S 9 ), the first storage capacitor (C 1 ), and the second storage capacitor (C 2 ).
The first switching element (S 1 ′) may include a first electrode (drain electrode or source electrode) electrically coupled to a control electrode of the third switching element (S 3 ), a second electrode (source electrode or drain electrode) electrically coupled to the input terminal (In), and a control electrode (gate electrode) electrically coupled to the input terminal (In). When a clock signal at a low level is supplied to the control electrode, the first switching element (S 1 ′) is turned on to supply an input signal supplied from the input terminal (In) to the control electrode of the third switching element (S 3 ).
The coupling scheme of the second through ninth switching elements (S 2 through S 9 ), the first storage capacitor (C 1 ) and the second storage capacitor (C 2 ) corresponds to the coupling scheme described above with regard to the first exemplary light emitting control driving circuit 300 shown in FIG. 3 .
FIG. 9 illustrates a timing diagram of exemplary signals employable for driving the light emitting control driving circuit 300 ′ shown in FIG. 8 .
As shown in FIG. 9 , in embodiments of the invention, like the timing diagram of the light emitting control driving circuit 300 shown in FIG. 5 , the timing diagram of the exemplary signals employable for driving light emitting control driving circuit 300 ′ shown in FIG. 8 may include the first driving period (T 51 ), the second driving period (T 52 ), and the third driving period (T 53 ).
During the first driving period (T 51 ), when an input signal at a low level is supplied to the input terminal (In), the first switching element (S 1 ′) is turned on and a clock signal at a low level is supplied to the first clock terminal (clka) such that the second switching element (S 2 ) and the fifth switching element (S 5 ).are turned on. First, the first switching element (S 1 ′) is turned on to supply an input signal at the low level supplied from the input terminal (In) to the control electrode of the third switching element (S 3 ). When the third switching element (S 3 ) receives the input signal at the low level, the third switching element (S 3 ) is turned on and supplies a clock signal at a high level supplied from a second clock terminal (clkb) to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ). The fourth switching element (S 4 ) and the seventh switching element (S 7 ), which receive the clock signal at the high level and the first power voltage, are turned off. The first storage capacitor (C 1 ) coupled between the first electrode and the control electrode of the third switching element (S 3 ) may store a voltage corresponding to the voltage difference of the first power voltage received from the second switching element (S 2 ) and the input signal received from the first switching element (S 1 ′).
Next, the fifth switching element (S 5 ) is turned on and applies the second power voltage of the second power supply line (VSS) to the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ) such that the sixth switching element (S 6 ) and the ninth switching element (S 9 ) are turned on. When the sixth switching element (S 6 ) is turned on, the sixth switching element (S 6 ) applies the first power voltage of the first power supply line (VDD) to the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB) such that the eighth switching element (S 8 ) is turned off and the first power voltage is output through the negative output terminal (OutB). Further, the ninth switching element (S 9 ) is turned on and outputs the second power voltage of the second power supply line (VSS) to the output terminal (Out). At this time, the second storage capacitor (C 2 ) may store the voltage corresponding to the voltage difference between the second power voltage received from the fifth switching element (S 5 ) and the second power voltage received from the ninth switching element (S 9 ). The voltage stored in the second storage capacitor (C 2 ) may be used to compensate for voltage lost in the driving circuit 300 ′ when the second power voltage is output.
During the second driving period (T 52 ), when an input signal at a high level is supplied to the input terminal (In), the first switching element (S 1 ′) is turned off. Further, when the clock signal at a high level is supplied to the first clock terminal (clka), the second switching element (S 2 ) and the fifth switching element (S 5 ) are turned off. At this time, the third switching element (S 3 ) is turned on with the voltage stored in the first storage capacitor (C 1 ) during the first driving period (T 51 ), and supplies the clock signal at a low level supplied from the second clock terminal (clkb) to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ). The fourth switching element (S 4 ) and the seventh switching element (S 7 ) receive the clock signal at the low level and are turned on. First, the fourth switching element (S 4 ) is turned on and applies the first power voltage of the first power supply line (VDD) to the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ) such that the sixth switching element (S 6 ) and the ninth switching element (S 9 ) are turned off.
Next, the seventh switching element (S 7 ) is turned on and applies the second power voltage of the second power supply line (VSS) to the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB) such that the eighth switching element (S 8 ) is turned on and the second power voltage is output through the negative output terminal (OutB). Further, the eighth switching element (S 8 ) is turned on and outputs the first power voltage of the first power supply line (VDD) to the output terminal (Out). At this time, the second storage capacitor (C 2 ) stores the voltage corresponding to the voltage difference between the first power voltage received from the fourth switching element (S 4 ) and the first power voltage received from the eighth switching element (S 8 ). The voltage stored in the second storage capacitor (C 2 ) may be used to compensate for the voltage lost in the driving circuit 300 ′ when the first power voltage is output. Further, since the first switching element (S 1 ′) is turned off, the light emitting control driving circuit 300 ′ operates without any change regardless of whether the input signal to be supplied to the input terminal (In) is at a high level or at a low level.
During the third driving period (T 53 ), when the input signal at a high level is supplied to the input terminal (In), the first switching element (S 1 ′) is turned off. Further, when the clock signal at a low level is supplied to the first clock terminal (clka), the second switching element (S 2 ) and the fifth switching element (S 5 ) are turned on. When the second switching element (S 2 ) is turned on, the first power voltage of the first power supply line (VDD) is applied to the control electrode of the fourth switching element (S 4 ) and the control electrode of the seventh switching element (S 7 ). The fourth switching element (S 4 ) and the seventh switching element (S 7 ) are turned off due to the first power voltage received from the second switching element (S 2 ). When the fifth switching element (S 5 ) is turned on, the second power voltage of the second power supply line (VSS) is applied to the control electrode of the sixth switching element (S 6 ) and the control electrode of the ninth switching element (S 9 ) such that the sixth switching element (S 6 ) and the ninth switching element (S 9 ) are turned on. When the sixth switching element (S 6 ) is turned on, the sixth switching element (S 6 ) applies the first power voltage of the first power supply line (VDD) to the control electrode of the eighth switching element (S 8 ) and the negative output terminal (OutB) such that the eighth switching element (S 8 ) is turned off and the first power voltage is output through the negative output terminal (OutB). Further, the ninth switching element (S 9 ) is turned on and outputs the second power voltage of the second power supply line (VSS) to the output terminal (Out). At this time, the second storage capacitor (C 2 ) stores the voltage corresponding to the voltage difference between the second power voltage received from the fifth switching element (S 5 ) and the second power voltage received from the ninth switching element (S 9 ). The voltage stored in the second storage capacitor (C 2 ) may be used to compensate for voltage lost in the driving circuit 300 ′ when the second power voltage is output.
FIG. 10 illustrates a timing diagram of exemplary signals employable for driving the light emitting control driver 130 shown in FIG. 2 .
As described above, the light emitting control driver 130 described below may include, e.g., the light emitting control driving circuit 300 and/or 300 ′ described in FIGS. 3 and 8 . That is, operation of the first light emitting control driving unit (Emission_ 1 ) to the n/ 2 -th light emitting control driving unit (Emission_n/ 2 ) may be the same as described with regard to the timing diagrams illustrated in FIGS. 4 and 9 .
As illustrated in FIG. 10 , the timing chart of the light emitting control driver 130 may include the first driving period (T 1 ), the second driving period (T 2 ), the third driving period (T 3 ), the fourth driving period (T 4 ) and the fifth driving period (T 5 ).
As described above, the first light emitting control driving unit (Emission_ 1 ) may include a first clock terminal (clka) electrically coupled to the first clock line (CLK 1 ), a second clock terminal (clkb) electrically coupled to the first negative clock line (CLKB 1 ), and an input terminal (In) electrically coupled to the initial driving line (Sp).
During the first driving period (T 1 ), the first light emitting control driving unit (Emission_ 1 ) may receive a first clock signal at a low level, a first negative clock signal of a high level, and an initial driving signal at a low level, and may output a first light emitting control signal at a low level to the first light emitting control line (Em[ 1 ]) of an output terminal (Out) thereof, and may output the first light emitting negative control signal at a high level to the first light emitting negative control line (EmB[ 1 ]) of a negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the first driving period (T 1 ), the operation of the first light emitting control driving unit (Emission_ 1 ) may be same as the operation of the light emitting control driving circuit 300 and/or 300 ′ during the first driving period (T 51 ), as described with reference to FIGS. 4 and 9 .
During the second driving period (T 2 ), the first light emitting control driving unit (Emission_ 1 ) may receive a first clock signal at a high level, a first negative clock signal at a low level, and an initial driving signal at a high level, may output the first light emitting control signal of a high level to the first light emitting control line (Em[ 1 ]) via the output terminal (Out) thereof, and may output the first light emitting negative control signal at a low level to the first light emitting negative control line (EmB[ 1 ]) via the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the second driving period (T 2 ), the operation of the first light emitting control driving unit (Emission_ 1 ) may be same as the operation of the light emitting control driving circuit 300 and/or 300 ′ during the second driving period (T 52 ), as described with reference to FIGS. 4 and 9 .
Further, during the second driving period (T 2 ), when the first light emitting control signal at a high level may be output by the first light emitting control driving unit (Emission_ 1 ) to the first light emitting control line (Em[ 1 ]), the first pixel unit (PS_ 1 ) and the second pixel unit (PS_ 2 ) may operate when they respectively receive a scan signal at a low level from the first scan line (Scan[ 1 ]) and the second scan line (Scan[ 2 ]).
As described above, the second light emitting control driving unit (Emission_ 2 ) may include a first clock terminal (clka) electrically coupled to the second clock line (CLK 2 ), a second clock terminal (CLKB) electrically coupled to the second negative clock line (CLKB 2 ), and an input terminal (In) electrically coupled to the first light emitting negative control line (EmB[ 1 ]).
During the second driving period (T 2 ), the second light emitting control driving unit (Emission_ 2 ) may receive the second clock signal at a low level, a second negative clock signal at a high level, and a first light emitting negative control signal at a low level, may output the second light emitting control signal at a low level to the second light emitting control line (Em[ 2 ]) of the output terminal (Out) thereof, and may output the second light emitting negative control signal of a high level is output to the second light emitting negative control line (EmB[ 2 ]) of the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the second driving period (T 2 ), the operation of the second light emitting control driving unit (Emission_ 2 ) may be the same as the operation of the light emitting control driving circuit 300 , 300 ′ during the first driving unit (T 51 ), as described with reference to FIGS. 4 and 9 .
During the third driving period (T 3 ), the first light emitting control driving unit (Emission_ 1 ) may operate in a same manner as it operated during the second driving period (T 2 ).
During the third driving period (T 3 ), a second clock signal at a high level, a second negative clock signal at a low level, and a first light emitting negative control signal at a low level may be applied to the second light emitting control driving unit (Emission_ 2 ), and the second light emitting control driving unit (Emission_ 2 ) may output the second light emitting control signal at a high level to the second light emitting control line (Em[ 2 ]) via the output terminal (Out) thereof, and the second light emitting negative control signal at a low level to the second light emitting negative control line (EmB[ 2 ]) via the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the third driving period (T 3 ), the operation of the second light emitting control driving unit (Emission_ 2 ) may be the same as the operation of the light emitting control driving circuit 300 , 300 ′ during the second driving period (T 52 ) described with reference to FIGS. 4 and 9 .
Further, during the third driving period (T 3 ), when the second light emitting control signal at a high level may be output by the second light emitting control driving unit (Emission_ 2 ) to the second light emitting control line (Em[ 2 ]), the third pixel unit (PS_ 3 ) and the fourth pixel unit (PS_ 4 ) may operate when they respectively receive a scan signal at a low level from the third scan line (Scan[ 3 ]) and the fourth scan line (Scan[ 4 ]).
As described above, the third light emitting control driving unit (Emission_ 3 ) may include a first clock terminal (clka) electrically coupled to the first negative clock line (CLKB 1 ), a second clock terminal (clkb) electrically coupled to the first clock line (CLK 1 ), and an input terminal (In) electrically coupled to the second light emitting negative control line (EmB[ 2 ]).
During the third driving period (T 3 ), the third light emitting control driving unit (Emission_ 3 ) may receive a first clock signal at a high level, a first negative clock signal at a low level, and a second light emitting negative control signal at a low level, and the third light emitting control driving unit (Emission_ 3 ) may output the third light emitting control signal at a low level to the third light emitting control line (Em[ 3 ]) via the output terminal (Out) thereof, and the third light emitting negative control signal at a high level to the third light emitting negative control line (EmB[ 3 ]) via the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the third driving period (T 3 ), the operation of the third light emitting control driving unit (Emission_ 3 ) may be the same as the operation of the light emitting control driving circuit 300 , 300 ′ during the first driving period (T 51 ), as described with regard to FIGS. 4 and 9 .
During the fourth driving period (T 4 ), a first clock signal at a low level, a first negative clock signal at a high level, and an initial driving signal of a high level may be applied to the first light emitting control driving unit (Emission_ 1 ), and the first light emitting control driving unit (Emission_ 1 ) may output the first light emitting control signal at a low level to the first light emitting control line (Em[ 1 ]) via the output terminal (Out) thereof, and may output the first light emitting negative control signal at a high level to the first light emitting negative control line (EmB[ 1 ]) via the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the fourth driving period (T 4 ), the operation of the first light emitting control driving unit (Emission_ 1 ) may be the same as the operation of the light emitting control driving circuit 300 , 300 ′ during the third driving period (T 53 ), as described with reference to FIGS. 4 and 9 .
During the fourth driving period (T 4 ), the second light emitting control driving unit (Emission_ 2 ) may operate in a same manner as it operated during the third driving period (T 3 ).
During the fourth driving period (T 4 ), the third light emitting control driving unit (Emission_ 3 ) may receive a first clock signal at a low level, a first negative clock signal at a high level, and a second light emitting negative control signal at a high level, and the third light emitting control driving unit (Emission_ 3 ) may output the third light emitting control signal at a high level to the third light emitting control line (Em[ 3 ]) via the output terminal (Out) thereof, and the third light emitting negative control signal at a low level to the third light emitting negative control line (EmB[ 3 ]) via the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the fourth driving period (T 4 ), the operation of the third light emitting control driving unit (Emission_ 3 ) may be the same as the operation of the light emitting control driving circuit 300 , 300 ′ during the second driving period (T 52 ), as described in FIGS. 4 and 9 .
Further, during the fourth driving period (T 4 ), when the third light emitting control signal at a high level is output to the third light emitting control line (Em[ 3 ]) by the third light emitting control driving unit (Emission_ 3 ), the fifth pixel unit (PS_ 5 ) and the sixth pixel unit (PS_ 6 ) may operate when they respectively receive a scan line at a low level from the fifth scan line (Scan[ 5 ]) and the sixth scan line (Scan[ 6 ]).
As described above, the fourth light emitting control driving unit (Emission_ 4 ) may include a first clock terminal (clka) electrically coupled to the second negative clock line (CLKB 2 ), a second clock terminal (clkb) electrically coupled to the second clock line (CLK 2 ), and an input terminal (In) electrically coupled to the third light emitting negative control line (EmB[ 3 ]).
During the fourth driving period (T 4 ), the fourth light emitting control driving unit (Emission_ 4 ) may receive a second clock signal at a high level, a second negative clock signal of a low level, and a third light emitting negative control signal at a low level, and the fourth light emitting control driving unit (Emission_ 4 ) may output the fourth light emitting control signal at a low level to the fourth light emitting control line (Em[ 4 ]) via the output terminal (Out) thereof, and the fourth light emitting negative control signal at a high level to the fourth light emitting negative control line (EmB[ 4 ]) via the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the fourth driving period (T 4 ), the operation of the fourth light emitting control driving unit (Emission_ 4 ) may be the same as the operation of the light emitting control driving circuit 300 , 300 ′ during the first driving period (T 51 ), as described with regard to FIGS. 4 and 9 .
During the fifth driving period (T 5 ), the first light emitting control driving unit (Emission_ 1 ) may operate in a same manner as it operated during the fourth driving period (T 4 ).
During the fifth driving period (T 5 ), the second light emitting control driving unit (Emission_ 2 ) may receive a second clock signal at a low level, a second negative clock signal at a high level, and a first light emitting negative control signal at a high level, and the second light emitting control driving unit (Emission_ 2 ) may output the second light emitting control signal at a low level to the second light emitting control line (Em[ 2 ]) via the output terminal (Out) thereof, and the second light emitting negative control signal at a high level to the second light emitting negative control line (EmB[ 2 ]) via the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the fifth driving period (T 5 ), the operation of the second light emitting control driving unit (Emission_ 2 ) may be the same as the operation of the light emitting control driving circuit 300 , 300 ′ during the third driving period (T 53 ), as described with regard to FIGS. 4 and 9 .
During the fifth driving period (T 5 ), the third light emitting control driving unit (Emission_ 3 ) may operate in a same manner as it operated during the fourth driving period (T 4 ).
During the fifth driving period (T 5 ), the fourth light emitting control driving unit (Emission_ 4 ) may receive a second clock signal at a low level, a second negative clock signal at a high level, and a third light emitting negative control signal at a low level, and the fourth light emitting control driving unit (Emission_ 4 ) may output the fourth light emitting control signal at a high level to the fourth light emitting control line (Em[ 4 ]) via the output terminal (Out) thereof, and the fourth light emitting negative control signal at a low level to the fourth light emitting negative control line (EmB[ 4 ]) via the negative output terminal (OutB) thereof. Thus, in embodiments of the invention, during the fifth driving period (T 5 ), the operation of the fourth light emitting control driving unit (Emission_ 4 ) may be the same as the operation of the light emitting control driving circuit 300 , 300 ′ during the second driving period (T 52 ), as described with reference to FIGS. 4 and 9 .
Further, during the fifth driving period (T 5 ), when the fourth light emitting control signal at a high level may be output by the fourth light emitting control driving unit (Emission_ 4 ) to the fourth light emitting control line (Em[ 4 ]), the seventh pixel unit (PS_ 7 ) and the eighth pixel unit (PS_ 8 ) may operation when they respectively receive a scan line at a low level from the seventh scan line (Scan[ 7 ]) and the eighth scan line (Scan[ 8 ]).
During subsequent driving period(s), e.g., (T 6 ), (T 7 ), etc., operations of the respective light emitting control driving units may substantially correspond to the operations of the first light emitting control driving unit to the fourth light emitting control driving unit (Emission_ 1 to Emission_ 4 ) during the first driving period (T 1 ) to the fifth driving period (T 5 ).
As illustrated above, an organic light emitting display and a driving circuit thereof according to embodiments of the present invention may be advantageous over conventional displays by enabling a size of the driving circuit and a manufacturing cost to be reduced, and a manufacturing yield thereof to be improved as one light emitting control driving line may be electrically coupled to pixels of multiple, e.g., two, rows, and thus a light emitting control signal may be provided to the pixels of multiple, e.g., two, rows simultaneously.
Further, as illustrated above, an organic light emitting display and a driving circuit thereof according to embodiments of the present invention may be advantageous by enabling a manufacturing cost and time to be reduced and for the yield to be improved as the light emitting control driving circuit may be implemented using transistors of only a same type as that of transistor(s) employed for implementing a pixel.
In above explanation, only exemplary embodiments of an organic light emitting display and a driving circuit thereof according to the present invention are explained, but the present invention is not limited to above described embodiments, and it is to be noted that various modifications may be realized by the person having a common knowledge in the art to which the present invention belongs without deviating the scope of the present invention, which is claimed in the claims illustrated as below within the spirit of the present invention.
|
A driving circuit including a plurality of light emitting control drivers includes an input terminal coupled to an initial driving line or a light emitting negative control line of a previous light emitting control driver, a first clock terminal and a second clock terminal that are electrically coupled to a first clock line and a first negative clock line that are phase-inverted, or a second clock line and a second negative clock line, respectively, and an output terminal and a negative output terminal adapted to generate an output signal and a negative output signal when receiving an input signal, a clock signal and a negative clock signal via the input terminal, the first clock terminal and the second clock terminal, respectively.
| 6
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to methods for drilling boreholes in subterranean formations, particularly hydrocarbon bearing formations, and to drilling fluids for use in such drilling operations. More particularly, the present invention relates to oil or synthetic based drilling fluids, fluids comprising invert emulsions, and more particularly drilling fluid additives that facilitate or enhance emulsification, electrical stability or filtration properties of the drilling fluid.
2. Description of Relevant Art
A drilling fluid or mud is a specially designed fluid that is circulated through a wellbore as the wellbore is being drilled to facilitate the drilling operation. The various functions of a drilling fluid include removing drill cuttings from the wellbore, cooling and lubricating the drill bit, aiding in support of the drill pipe and drill bit, and providing a hydrostatic head to maintain the integrity of the wellbore walls and prevent well blowouts. Specific drilling fluid systems are selected to optimize a drilling operation in accordance with the characteristics of a particular geological formation.
Oil or synthetic-based muds, or invert emulsions, are normally used to drill swelling or sloughing shales, salt, gypsum, anhydrite or other evaporite formations, hydrogen sulfide-containing formations, and hot (greater than about 300 degrees Fahrenheit) holes, but may be used in other holes penetrating a subterranean formation as well. These non-aqueous based drilling fluids typically contain oil or a synthetic oil or other synthetic material or synthetic fluid (“synthetic”) as the continuous phase and may also contain water which is dispersed in the continuous phase by emulsification so that there is no distinct layer of water in the fluid. The term “oil mud” or “oil or synthetic-based mud” typically means an invert oil mud emulsion or invert emulsion. An all oil mud simply comprises 100% oil by volume as the liquid phase; that is, there is no aqueous internal phase. An invert emulsion drilling fluid may commonly comprise between about 50:50 to 95:5 by volume oil phase to water phase.
Most commonly, invert emulsions used in drilling typically comprise: a base oil or synthetic fluid for the external phase; a saline, aqueous solution for the internal phase (typically a solution comprising about 30% calcium chloride); and other agents or additives for suspension, fluid loss, density, oil-wetting, emulsification, filtration, and rheology control. With space at some well sites limited, such as on offshore platforms, and with increasing costs of transport of materials to a wellsite, there is industry-wide interest in, and on-going need for, more efficient and concentrated drilling fluid additives and for drilling fluids which can be formulated and maintained with minimal or fewer additives than common with prior art drilling fluids.
SUMMARY OF THE INVENTION
An improved and more efficient material or product and method is disclosed for providing emulsion stability and filtration control to invert emulsions and other oil or synthetic based drilling fluids for use in drilling boreholes in subterranean formations, particularly hydrocarbon bearing formations.
The product of the invention has the advantage of a pour point at temperatures as low as about 20 degrees Fahrenheit with minimal solvent. Thus, the product of the invention may be transported in a highly (about 90% to about 100%) active state, which reduces the need to inventory products containing different solvents for compatibility with the drilling fluid. This advantage further eliminates the need for shipping large amounts of inert material. Moreover, the product of the invention has the further advantage of providing high levels of filtration control to a drilling fluid made with conventional emulsifiers, especially at temperatures up to about 250° F. Still further, the product of this invention, when added to drilling fluids, reduces or eliminates the need for conventional fluid loss additives.
The product of this invention comprises two primary components or parts. One part is a carboxylic acid-terminated polyamide and the other part is itself a mixture produced by the Diels-Alder reaction of dienophiles, preferably carboxylic acids, polycarboxylic acids, acid anhydrides, or combinations or mixes thereof, with a mixture of fatty acids and resin acids. These two components or parts are blended or mixed and further reacted with cations to form soaps. This saponification reaction may be achieved in the manufacturing process or it may be effected “in situ” by the presence of or addition of cations to the drilling fluid. As used herein, the term “in situ” shall be understood to mean in the drilling fluid. Typically, such saponification reaction will occur in the drilling fluid when the drilling fluid is being prepared for use as a drilling fluid or when the drilling fluid is in use as a drilling fluid in drilling a borehole in a subterranean formation. Drilling fluids commonly comprise cations. Sources of such cations include, without limitation, lime, quicklime, and calcium chloride, among others. Further, drilling fluids may incorporate cations contacted in or available from the subterranean formation itself. The method of the invention employs the product of the invention for improved drilling fluids and improved drilling of boreholes in subterranean formations.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph comparing the electrical stability of a synthetic based drilling fluid containing the product of the invention with the same synthetic based drilling fluid containing conventional emulsifiers instead of the product of the invention, using data from Tables 1 and 2.
FIG. 2 is a graph comparing HTHP filtration of a synthetic based drilling fluid containing the product of the invention with the same synthetic based drilling fluid containing conventional emulsifiers instead of the product of the invention, using data from Tables 3 and 4.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The product of the invention comprises a blend, mixture, or a combination (hereinafter “blend) of a carboxylic acid-terminated polyamide (“Component ‘A’”) and a mixture (“Component ‘B’”) produced by the Diels-Alder reaction of dienophiles, preferably carboxylic acids, polycarboxylic acids, and anhydrides, or combinations or mixes thereof, with a mixture of fatty acids and resin acids. Component B has a ratio of fatty acids to resin acids preferably ranging from about 4:1 to about 1:1 and a most preferred ratio of about 2:1 and is preferably comprised of fatty acids and resin acids derived from the distillation of crude tall oil.
Component A is preferably concentrated (i.e., about 90% active), and typically made from the condensation reaction between fatty acids and polyamines. The fatty acids and polyamines are reacted in such proportion as to create a “partial amide” intermediate product having a mole ratio of the reactive acid sites to amine sites ranges from about 0.5:1 to about 0.75:1 and most preferably about 0.6:1. This partial amide intermediate product is diluted with a minimum amount of solvent, as needed for further processing, and the remaining amine sites are further reacted with an acid anhydride or polycarboxylic acid to produce the carboxylic acid-terminated polyamide. A most preferred carboxylic acid-terminated fatty polyamide for use in the invention is EZ-MUL® NT CONCENTRATE, the active constituent of EZ-MUL® NT available from Halliburton Energy Services, Inc. in Houston, Tex., although other carboxylic acid terminated fatty polyamides are believed to be useable.
In comprising the product of the invention, the preferred ratio of Component A to Component B is about 1:5 to about 1:1. Ratios of Component A to Component B of about 1:2 to about 1:3 are most preferred. The exact ratio of these two components or parts may vary greatly depending on the exact desired characteristics of the product. Preferably, however, the quantity of Component B will exceed the quantity of Component A.
The blend comprising the product of the invention is preferably made by blending, mixing, or combining these two components—the polyamide and the modified fatty acid/resin acid mixture—together. After blending, the polyamide and fatty acid/resin acid components are reacted with cations to form soaps. Such reaction or saponification may be achieved as part of the manufacturing process of the product of the invention or may be effected in situ the drilling fluid by the presence or addition of cations to the drilling fluid. Calcium cations are preferred and may be obtained, for example, by reacting the polyamide and modified fatty acid/resin acid components with lime, quicklime, or calcium chloride.
Tall oil is a commonly known product made from acid treatment of alkaline liquors obtained from the manufacture of wood pulp, and tall oil and its derivatives have previously been used in oil-well drilling muds. However, the modified fatty acid/resin acid component of the blend of the product of the invention alone is not effective for achieving the advantages of the invention. EZ-MUL® is known to have utility as an emulsifier for oil based drilling fluids. However, carboxylic acid-terminated fatty polyamides alone cannot achieve all of the advantages of the invention. In the combination disclosed, however, the blend (or mixture) comprising the product of the invention provides a marked advance in the art.
The product of the invention is a powerfully efficient additive for oil or synthetic based drilling fluids, affording or effecting enhanced emulsification, and improved electrical stability and fluid loss control, with significantly less volume of additive than previously known or available with prior art drilling fluid additives. The product effects or helps facilitate emulsification typically in amounts of about one-third the quantity commonly needed for emulsification of oil or synthetic based fluids with prior art emulsifiers. That is, amounts of about three pounds to about five pounds of the product of the invention per barrel of drilling fluid can be effective for emulsification. Even lower quantities can improve the electrical stability and filtration control of drilling fluids, even if already emulsified with other emulsifiers.
The product of the invention does not rely on a carrier. The material comprising the product is highly active and is believed to be useful with all or substantially all synthetic and oil-based systems known to be effective for drilling fluids. The product of the invention may also add viscosity to the drilling fluid and thus is preferably added to the base drilling fluid before any weighting agents such as barite, for example, are added.
The product of this invention is stable even at temperatures up to (and including) about 250 degrees Fahrenheit without filtration additives and up to about 300 to about 350 degrees Fahrenheit with filtration additives. Adding wetting agents along with the product of the invention in an emulsifier package may improve the oil-wetting nature of the drilling fluid in some base oils but will not be needed in others. Wetting agents may also improve the rheological stability at temperatures up to about 300° F. The addition of wetting agents to drilling fluids comprising the product of the invention may also further enhance performance of some fluid systems.
The product of the invention has a high acid value. Consequently, improved results may be seen when a neutralizer or neutralizing agent is added to the drilling fluid. For example, a minimum of about eight pounds of lime (or similar saponifying agent) might favorably be added per barrel of drilling fluid when about three pounds per barrel of the product of the invention are used in the drilling fluid. Additional lime (or similar saponifying agent) may be helpful or needed with larger quantities of product of the invention for optimum results, although satisfactory results might also be obtained with less.
Care is recommended when using the product of this invention to avoid over-treating. Excess emulsifiers (i.e., more than needed to effect emulsification) in drilling fluids can contribute to high fluid viscosity at cold temperatures (i.e., temperatures less than about 45 degrees Fahrenheit). For deepwater operations (i.e., use of drilling fluids at depths of water greater than about 500 feet and at temperatures less than about 45 degrees Fahrenheit), wetting agents may preferably be added to help maintain low riser viscosities as drill solids are incorporated in or become carried by the drilling fluid.
The method of the invention comprises adding the product of the invention to an oil or synthetic based drilling fluid or employing a drilling fluid comprising the product of the invention in drilling a borehole in a subterranean formation. In another embodiment, the method of the invention comprises adding the product of the invention to an oil or synthetic based drilling fluid to facilitate emulsification of the drilling fluid or the formation of invert emulsions.
Experiments were conducted that demonstrate or exemplify the invention. Several formulations of synthetic or oil-based drilling fluids were prepared, typical of those used in the field, and all of which comprised invert emulsions. Specifically, samples of drilling fluids were prepared comprising a synthetic or diesel oil base, to which additives were added, including the product of n the invention or a known emulsifier for comparison, as indicated in Tables 1-12 below. The different samples were subjected to different conditions, such as high temperatures or hot rolling, or further additives or contaminants, for example, simulated drill solids or salt water, for comparison of performance and properties. The results of tests tabulated in Tables 1-4 are graphed in FIGS. 1 and 2.
As used in the tables, the following compounds or products have the meanings indicated below:
SF BASE™ is a synthetic oil base for drilling fluids typically used in drilling mud systems such as PETROFREE® SF, available from Halliburton Energy Services, Inc. in Houston Tex.;
LE BASE® is a synthetic oil base for drilling fluids typically used in drilling mud systems such as PETROFREE® LE;
GELTONE® II, is an organoclay for improving viscosity characteristics;
SUSPENTONE® is an organoclay for improving the ability of a drilling fluid to suspend drill cuttings;
INVERMUL® is an emulsifier;
EZ MUL® is an emulsifier;
LE SUPERMUL® is an emulsifier;
LE MUL® is an emulsifier;
DRIL TREAT™ is a wetting agent;
DEEP-TREAT™ is a wetting agent;
BAROID® is barite, a weighting agent;
DURATONE® HT is a filtration control agent; and
BDF-258™ is the product of the invention.
All trademarks are the property of Halliburton Energy Services, Inc. and the products are available from Halliburton Energy Services, Inc. in Houston, Tex.
TABLE I
PETROFREE ® SF
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
Sample Mark
A (7.33 lb/bbl Active emulsifier content)
SF BASE, bbl
0.516
Freshwater, bbl
0.181
GELTONE ® II, lb
3
SUSPENTONE ™, lb
1
LE ™ MUL, lb
4
LE ™ SUPERMUL, lb
6
Lime, lb
5
DURATONE ® HT, lb
7
BAROID ®, lb
330
Calcium chloride, lb
21.9
DEEP-TREAT ™, lb
3
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing:
mixed 10 minutes after rolling
Rev Dust, lb
—
45
—
15% NaCl Brine Added,
—
—
33
% vol
Hot rolled @250° F., hr
—
16
16
16
Temperature, ° F.
120
40
120
40
120
40
120
Plastic viscosity, cP
23
80
24
112
37
108
38
Yield point, lb/100 ft 2
15
18
8
19
8
26
11
10 Sec gel, lb/100 ft 2
8
7
6
10
7
9
6
10 Min gel, lb/100 ft 2
9
11
8
18
10
12
10
Electrical stability, v
690
235
488
77
HTHP filtrate @250° F., ml
2.4
2.4
10.4
7.6 (0.5 water)
Fann 35 dial readings
600 rpm
61
178
56
243
82
242
87
300 rpm
38
98
32
131
45
134
49
200 rpm
29
69
24
91
33
94
36
100 rpm
20
38
15
51
20
53
23
6 rpm
7
7
5
10
5
10
7
3 rpm
6
6
4
9
4
8
6
Note
Contaminated samples were made up with mud already hot rolled 16 hr.@250° F.
TABLE 2
PETROFREE ® SF
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
Sample Mark
H3
SF BASE, bbl
0.516
Freshwater, bbl
0.181
GELTONE ® II, lb
3
SUSPENTONE ™, lb
1
BDF-258, lb
3
Lime, lb
8
DURATONE ® HT, lb
7
BAROID ®, lb
330
Calcium chloride, lb
21.9
DEEP-TREAT ™, lb
3
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing:
mixed 10 minutes after rolling
Rev Dust, lb
—
45
—
15% NaCl Brine Added,
—
—
33
% vol
Hot rolled @250° F., hr
—
—
16
16
16
Temperature, ° F.
120
40
120
40
120
40
120
40
120
Plastic viscosity, cP
29
78
27
72
26
N/A
49
113
43
Yield point, lb/100 ft 2
16
33
14
24
12
N/A
24
43
20
10 Sec gel, lb/100 ft 2
8
15
7
13
7
27
16
19
13
10 Min gel, lb/100 ft 2
10
17
9
15
9
57
36
20
13
Electrical stability, v
638
669
630
884
393
HTHP filtrate @250° F., ml
2.0
1.6
5.2
2.4
Fann 35 dial readings
600 rpm
74
189
68
168
64
O/S
122
269
106
300 rpm
45
111
41
96
38
186
73
156
63
200 rpm
35
82
32
72
30
139
56
116
48
100 rpm
24
53
22
45
20
88
38
72
32
6 rpm
9
17
8
14
8
29
15
21
12
3 rpm
8
15
7
12
7
26
14
19
11
Note
O/S indicates an off-scale reading, or >300. Contaminated samples were made up with mud already rolled 16 hr @250° F.
TABLE 3
PETROFREE ® LE
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
Sample Mark
C
LE BASE, bbl
0.5094
Freshwater, bbl
0.1793
GELTONE ® II, lb
3.5
SUSPENTONE ™, lb
2
LE ™ MUL, lb
7
LE ™ SUPERMUL, lb
4
Lime, lb
7
DURATONE ® HT, lb
6
Calcium chloride, lb
21.8
BAROID ®, lb
332.3
DEEP-TREAT ™, lb
3.5
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing: mixed 10 minutes after rolling
Rev Dust, lb
—
45
—
15% NaCl Brine Added, % vol
—
—
33
Hot rolled @250° F., hr
—
—
16
16
16
Temperature, ° F.
120
40
120
40
120
40
120
40
120
Plastic viscosity, cP
23
94
22
77
23
82
32
87
35
Yield point, lb/100 ft 2
12
51
9
18
6
12
5
14
4
10 Sec gel, lb/100 ft 2
6
17
6
9
5
8
5
7
5
10 Min gel, lb/100 ft 2
9
21
8
15
7
15
8
10
6
Electrical stability, v
737
676
474
545
230
HTHP filtrate @250° F., ml
4.4
2.0
10.0
12.0-1.1 emul.
Fann 35 dial readings
600 rpm
58
239
53
172
52
176
69
188
74
300 rpm
35
145
31
95
29
94
37
101
39
200 rpm
26
108
24
67
22
66
28
70
29
100 rpm
17
66
16
38
13
37
17
38
17
6 rpm
6
19
5
9
4
8
4
7
5
3 rpm
5
17
4
8
3
7
3
6
4
Note
O/S indicates an off-scale reading, or >300. Contaminated samples were made up with mud already hot rolled 16 hr @250° F.
TABLE 4
PETROFREE ® LE
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
Sample Mark
B2
LE BASE, bbl
0.5163
Freshwater, bbl
0.1796
GELTONE ® II, lb
3
SUSPENTONE ™, lb
2
BDF-258, lb
3
Lime, lb
7
DURATONE ® HT, lb
6
Calcium chloride, lb
21.8
BAROID ®, lb
333.2
DEEP-TREAT ™, lb
3.3
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing: mixed 10 minutes after rolling
Rev Dust, lb
—
45
—
15% NaCl Brine Added, % vol
—
—
33
Hot rolled @250° F., hr
—
—
16
16
16
Temperature, ° F.
120
40
120
40
120
40
120
40
120
Plastic viscosity, cP
26
72
23
64
23
98
34
96
36
Yield point, lb/100 ft 2
12
29
9
16
7
26
6
32
11
10 Sec gel, lb/100 ft 2
7
14
6
12
6
13
6
16
10
10 Min gel, lb/100 ft 2
9
18
8
16
9
28
8
21
9
Electrical stability, v
554
615
568
574
269
HTHP filtrate @250° F., ml
2.2
2.2
3.0
1.8
Fann 35 dial readings
600 rpm
64
173
55
144
53
222
74
224
83
300 rpm
38
101
32
80
30
124
40
128
47
200 rpm
29
75
25
58
23
89
29
94
36
100 rpm
20
47
17
35
15
52
18
58
23
6 rpm
7
15
6
10
6
13
4
16
8
3 rpm
6
14
5
9
5
11
3
14
7
Note
O/S indicates an off-scale reading, or >300. Contaminated samples were made up with mud already hot rolled 16 hr @250° F.
TABLE 5
PETROFREE ® SF
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
Sample Mark
H2
LE BASE, bbl
0.516
Freshwater, bbl
0.181
GELTONE ® II, lb
3
SUSPENTONE ™, lb
1
BDF-258, lb
3
Lime, lb
8
DURATONE ® HT, lb
7
BAROID ®, lb
330
Calcium chloride, lb
21.9
DEEP-TREAT ™, lb
3
DRILTREAT ®, lb
1
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing: mixed 10 minutes after rolling
Rev Dust, lb
—
45
—
15% NaCl Brine Added, % vol
—
—
33
Hot rolled @250° F., hr
—
—
16
16
16
Temperature, ° F.
120
40
120
40
120
40
120
40
120
Plastic viscosity, cP
28
82
25
86
25
N/A
46
116
41
Yield point, lb/100 ft 2
14
36
16
29
14
N/A
22
45
22
10 Sec gel, lb/100 ft 2
7
17
7
14
8
28
18
19
12
10 Min gel, lb/100 ft 2
10
20
9
18
10
60
31
21
12
Electrical stability, v
603
694
684
846
409
HTHP filtrate @250° F., ml
1.2
1.6
4.0
1.6
Fann 35 dial readings
600 rpm
70
200
66
201
64
O/S
114
277
104
300 rpm
42
118
41
115
39
201
68
161
63
200 rpm
33
89
32
84
30
149
52
119
48
100 rpm
22
57
22
51
21
93
34
74
33
6 rpm
8
19
8
15
8
28
13
22
13
3 rpm
7
17
7
14
7
24
12
19
12
Note
O/S indicates an off-scale reading, or >300. Contaminated samples were made up with mud already rolled 16 hr @250° F.
TABLE 6
PETROFREE ® SF
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
NO DURATONE ® HT
Sample Mark
O
SF BASE, lb
0.516
Freshwater, bbl
0.181
GELTONE ® II, lb
4
SUSPENTONE ™, lb
1
BDF-258, lb
3
Lime, lb
9
Calcium chloride, lb
21.9
BAROID ®, lb
330
DRILTREAT ®, lb
1
DEEP-TREAT ™, lb
3
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing: mixed 10 minutes after rolling
Hot rolled @250° F., hr
—
—
16
16
16
Rev Dust, lb
—
—
—
45
—
15% NaCl brine, % vol
—
—
—
—
33
Temperature, ° F.
120
40
120
40
120
40
120
40
120
Plastic viscosity, cP
28
88
33
85
29
N/A
50
N/A
69
Yield point, lb/100 ft 2
5
19
8
20
8
N/A
5
N/A
45
10 Sec gel, lb/100 ft 2
5
10
7
9
5
5
3
48
25
10 Min gel, lb/100 ft 2
8
14
9
13
7
14
10
>60
62
Electrical stability @120° F., v
471
519
496/230
218
285
HTHP filtrate @250° F., ml
0.2
1.6
4.0
3.4-0.4 H 2 O
Fann 35 dial readings
600 rpm
61
195
74
190
66
O/S
105
O/S
183
300 rpm
33
107
41
105
37
173
55
O/S
114
200 rpm
25
75
31
75
27
123
39
256
87
100 rpm
16
43
20
44
17
68
21
163
57
6 rpm
5
10
7
10
5
7
3
45
26
3 rpm
4
8
6
8
4
5
2
40
24
Note
O/S indicates an off-scale reading, or >300. Contaminated samples were made up with mud already rolled 16 hr @250° F.
TABLE 7
INVERMUL ®
14 lb/gal; 250,000 WPS
Sample Mark
1
2
3
4
5
Diesel, bbl
0.5395
0.5234
0.5679
0.5743
0.5608
Fresh water, bbl
0.1814
0.1815
0.1449
0.1453
0.1454
Oil-to-Water Ratio
75/25
75/25
80/20
80/20
80/20
GELTONE ® II, lb
2
2
2
2
2
SUSPENTONE ™, lb
1
1
—
—
—
BDF-258, lb
3.5
—
6
3
—
INVERMUL ® NT, lb
—
3
—
—
3
Lime, lb
8
8
12
8
8
DURATONE ® HT, lb
6
6
6
6
6
EZ MUL ® NT, lb
—
6
—
—
6
Calcium chloride, lb
22.0
22.1
17.6
17.7
17.7
BAROID ®, lb
302
301
307
310
309
Rev Dust, lb
20
20
20
20
20
DRILTREAT ®, lb
—
—
—
1.5
—
Hot rolled @300° F., hr
—
—
—
16
—
16
—
16
Plastic viscosity @150° F., cP
25
26
21
23
22
19
20
22
Yield point, lb/100 ft 2
31
53
17
11
13
9
30
8
10 Sec gel, lb/100 ft 2
26
32
12
14
8
8
16
8
10 Min gel, lb/100 ft 2
34
34
23
29
15
16
16
9
Electrical stability, v
593
1140
923
1302
697
783
1404
766
HTHP filtrate @300° F., ml
11.6*
3.8
6.2
16.4
5.6
10.0
5.4
7.6
Fann 35 dial readings
600 rpm
81
105
59
57
57
47
70
52
300 rpm
56
79
38
34
35
28
50
30
200 rpm
46
69
30
26
28
21
42
23
100 rpm
36
56
22
17
19
14
32
16
6 rpm
21
33
10
8
8
7
17
7
3 rpm
20
32
9
7
7
6
16
6
*Trace of water/emulsion was seen in the filtrate.
TABLE 8
INVERMUL ®
14 lb/gal; 80/20 OWR with 250,000 WPS
Sample Mark
10
11
Diesel, bbl
0.577
0.577
Fresh water, bbl
0.145
0.145
GELTONE ® II, lb
6
6
BDF-258, lb
3
3
Lime, lb
8
8
Calcium chloride, lb
17.6
17.6
DEEP-TREAT ™, lb
1.5
1
BAROID ®, lb
312
312
Rev Dust, lb
20
20
DRILTREAT ®, lb
—
1
Hot rolled @ 150° F., hr
16
—
16
—
Hot rolled @ 250° F., hr
—
16
—
16
Plastic viscosity @ 150° F., cP
23
24
23
24
Yield point, lb/100 ft 2
28
10
25
12
10 Sec gel, lb/100 ft 2
17
10
18
11
10 Min gel, lb/100 ft 2
22
16
20
20
Electrical stability, v
686
783
561
723
HTHP filtrate @ 250° F., ml
5.6
6.8
6.6
9.4
HTHP filt. cake thickness, {fraction (1/32)}″
4
3
5
5
Fann 35 dial readings
600 rpm
74
58
71
60
300 rpm
51
34
48
36
200 rpm
42
26
39
28
100 rpm
32
17
30
19
6 rpm
17
7
17
8
3 rpm
16
6
17
8
Note: 0.4 lb/bbl DEEP-TREAT ™ was sufficient to wet in the barite and Rev Dust in mud 11. Additional product was added after the Rev Dust to total 1 lb/bbl.
TABLE 9
PETROFREE ® SF
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
NO DURATONE ® HT
Sample Mark
I
SF BASE, bbl
0.516
Freshwater, bbl
0.181
GELTONE ® II, lb
4
SUSPENTONE ™, lb
1
BDF-258, lb
3.5
Lime, lb
9
DURATONE ® HT, lb
—
Calcium chloride, lb
21.9
DEEP-TREAT ™, lb
3
BAROID ®, lb
330
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing: mixed 10 minutes after rolling
Hot rolled @250° F., hr
—
—
16
16
16
Rev Dust, lb
—
45
—
15% NaCl Brine Added, % vol
—
—
33
Temperature, ° F.
120
40
120
40
120
40
120
58
120
Plastic viscosity, cP
29
85
32
76
31
N/A
54
N/A
7
Yield point, lb/100 ft 2
9
17
9
15
6
N/A
7
N/A
53
10 Sec gel, lb/100 ft 2
7
10
8
9
7
6
4
55
34
10 Min gel, lb/100 ft 2
8
15
11
10
7
13
8
—
65
Electrical stability, v
482
529
241
234
293
HTHP filtrate @250° F., ml
1.6
2.8*
6.0
5.0-1.0 H 2 O
Fann 35 dial readings
600 rpm
67
187
73
167
68
O/S
115
O/S
195
300 rpm
38
102
41
91
37
186
61
278
124
200 rpm
29
73
31
65
28
130
43
220
97
100 rpm
19
42
20
38
18
71
23
151
67
6 rpm
6
10
7
9
6
8
3
53
29
3 rpm
5
8
6
7
5
5
2
50
28
Note
O/S indicates an off-scale reading, or >300. Contaminated samples were made up with mud already rolled 16 hr @250° F.
*Some small water droplets were observed in the filtrate
TABLE 10
PETROFREE ® SF
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
NO DURATONE ® HT
Sample Mark
N
SF BASE, lb
0.516
Freshwater, bbl
0.181
GELTONE ® II, lb
4
SUSPENTONE ™, lb
1
BDF-258, lb
3.5
Lime, lb
9
Calcium chloride, lb
21.9
DEEP-TREAT ™, lb
4
BAROID ®, lb
330
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing: mixed 10 minutes after rolling
Hot rolled @250° F., hrs
—
—
16
16
16
Rev Dust, lb
—
45
—
15% NaCl Brine Added, % vol
—
—
33
DEEP-TREAT ™, lb
—
2
2
Temperature, ° F.
120
40
120
40
120
40
120
40
120
Plastic viscosity, cP
35
103
38
80
31
124
44
N/A
53
Yield point, lb/100 ft 2
11
18
11
16
6
22
5
N/A
10
10 Sec gel, lb/100 ft 2
8
10
7
8
6
5
5
8
6
10 Min gel, lb/100 ft 2
14
16
11
9
7
8
7
10
7
Electrical stability
503
527
209
275
156
@120° F., v
HTHP filtrate @250° F., ml
0.6
1.2
1.6
1.0-trace emul
Fann 35 dial readings
600 rpm
81
224
87
176
68
270
93
O/S
116
300 rpm
46
121
49
96
37
146
49
189
63
200 rpm
35
85
37
68
29
101
35
134
44
100 rpm
22
49
24
39
18
55
20
74
25
6 rpm
7
10
7
8
6
6
4
10
5
3 rpm
6
8
6
7
5
4
3
7
4
Note
O/S indicates an off-scale reading, or >300. Contaminated samples were made up with mud already rolled 16 hr @250° F.
TABLE 11
PETROFREE ® SF
14 lb/gal; 75/25 OWR with 250,000 ppm WPS
Sample Mark
BB
SF BASE, lb
0.516
Freshwater, bbl
0.181
GELTONE ® II, lb
4
SUSPENTONE ™, lb
1
BDF-258, lb
3.5
Lime, lb
9
Calcium chloride, lb
21.9
BD QUAT 2HT, lb
1
BAROID ®, lb
330
DEEP-TREAT ™, lb
3
Mixed 15 minutes at 7000 rpm on a Silverson L4RT before testing: mixed 10 minutes after rolling
Hot rolled @250° F., hr
—
—
16
16
16
Rev Dust, lb
—
—
—
45
—
15% NaCl Brine Added, % vol
—
—
—
—
25
Temperature, ° F.
120
40
120
40
120
40
120
40
120
Plastic viscosity, cP
29
76
30
75
28
119
40
119
43
Yield point, lb/100 ft 2
15
32
17
24
10
16
6
35
14
10 Sec gel, lb/100 ft 2
8
14
8
11
7
7
5
15
8
10 Min gel, lb/100 ft 2
13
17
9
12
8
11
10
15
9
Electrical stability,
633
*486 average
333
576
223
@120° F., v
HTHP filtrate @250° F., ml
2.2
5.4
4.0
3.0-0.2 emul.
Fann 35 dial readings
600 rpm
73
184
77
174
66
254
86
273
100
300 rpm
44
108
47
99
38
135
46
154
57
200 rpm
34
81
36
73
30
93
33
111
42
100 rpm
23
52
24
45
19
50
19
65
26
6 rpm
8
16
8
13
7
7
4
15
8
3 rpm
7
14
7
11
6
5
3
13
7
Note
Contaminated samples were made up with mud already hot rolled 16 hr.@250° F.
*ES readings ranged from 347 to 656 volts.
TABLE 12
14.0 lb/gal PETROFREE SF
70/30 OWR: 250,000 ppm WPS
Sample Mark
Base - D. Carbajal FLC Evaluation Data
SF BASE, bbl
0.505
Freshwater, bbl
0.220
GELTONE ® II, lb
3
LE ™ MUL, lb
3
LE ™ SUPERMUL, lb
3
Lime, lb
5
BAROID ®, lb
330
Calcium chloride, lb
27
A 3-gal. batch was mixed at low shear; then 30 min on a Silverson L4RT
BDF-258, lb
—
1.5
3
Samples were mixed, then hot rolled 16 hours at 150° F.
Temperature, ° F.
40
120
40
120
40
120
Plastic viscosity, cP
75
26
90
30
97
32
Yield point, lb/100 ft 2
26
16
37
30
39
33
10 Sec gel, lb/100 ft 2
17
10
30
17
32
19
10 Min gel, lb/100 ft 2
18
12
30
20
33
24
Electrical stability, volts
259
650
679
HTHP filtrate @250° F.,
11.8
3.2
Trace
ml oil
HTHP filtrate @250° F.,
5.6
—
—
ml H 2 O
Fann 35 dial readings
600 rpm
176
68
217
90
233
97
300 rpm
101
42
127
60
136
65
200 rpm
74
33
94
49
101
54
100 rpm
47
27
61
36
66
40
6 rpm
16
10
23
17
26
20
3 rpm
16
9
20
15
23
18
These experimental results show that the product of the invention has emulsion-forming capabilities comparable to or exceeding prior art emulsifiers at only about one-third the concentration and that the product of the invention improves the electrical stability of the drilling fluid, even after heat stress. These results also show that the product of the invention imparts very low filtration properties to the drilling fluids. Further, the product of the invention provides significantly better filtration control than conventional emulsifiers, especially when used with a wetting agent, even after solids and brine contamination. Still further, the tests showed that no fluid loss control additives were needed for the same filtration properties as prior art emulsifiers when the product of the invention was used. The tests also indicate that the product of the invention performs well with other emulsifying products, which should allow simpler maintenance treatments in oil or synthetic based fluids when using the product of the invention.
In the method of the invention, the product of the invention is added to an oil or synthetic based drilling fluid or a drilling fluid comprising an invert emulsion to improve or facilitate the emulsification of the oil or synthetic base fluid.
The foregoing description of the invention is intended to be a description of preferred embodiments. Various changes in the details of the described product and method can be made without departing from the intended scope of this invention as defined by the appended claims.
|
A method and product is disclosed which provides emulsion stability and filtration control to invert emulsion drilling fluids. The product comprises a blend of a carboxylic acid terminated polyamide and a mixture produced by the Diels-Alder reaction of dienophiles, preferably carboxylic acids, polycarboxylic acids, acid anhydrides, or combinations or mixes thereof, with a mixture of fatty acids and resin acids. The product is extremely effective, decreasing by about two-thirds the amount of emulsifier generally required to formulate an effective drilling fluid. The product also greatly reduces and in many cases eliminates the need for conventional fluid loss additives, and additionally provides electrical stability. Moreover, the product has a pour point as low as about 20 degrees Fahrenheit with minimal solvents, thereby eliminating the need to ship large amounts of inert material for use, and may be transported in a highly active state.
| 2
|
I. FIELD OF THE INVENTION
[0001] The present invention relates generally to therapeutic hypothermia.
II. BACKGROUND OF THE INVENTION
[0002] Mild or moderate hypothermia may be induced to improve the outcomes of patients suffering from such maladies as stroke, cardiac arrest, myocardial infarction, traumatic brain injury, and high intracranial pressure. The present assignee has covered one or more of the above treatments using an intravascular heat exchange catheter in U.S. Pat. Nos. 6,149,670, 6,290,717, 6,432,124, 6,454,793, 6,682,551, and 6,726,710 (collectively, “the Alsius treatment patents”), all of which are incorporated herein by reference.
[0003] As recognized herein, shivering may accompany hypothermia, which not only can lead to patient discomfort but can also counter the therapy by warming the patient. U.S. Pat. Nos. 6,702,839, 6,582,457, and 6,231,594 (collectively, “the anti-shivering patents”), incorporated herein by reference, disclose various drugs and external heating blankets for alleviating such shivering in the context of intravascular heat exchange catheters. However, as also recognized herein, these latter three patents appear to fail to envision that hypothermia may be induced by means of externally applied pads such as those disclosed in U.S. Pat. Nos. 6,827,728, 6,818,012, 6,802,855, 6,799,063, 6,764,391, 6,692,518, 6,669,715, 6,660,027, 6,648,905, 6,645,232, 6,620,187, 6,461,379, 6,375,674, 6,197,045, and 6,188,930 (collectively, “the external pad patents”), all of which are incorporated herein by reference but none of which appear to recognize that shivering might occur when using external pads, much less what to do about it. The present invention rectifies this shortfall in the prior art.
SUMMARY OF THE INVENTION
[0004] A method for treating a patient includes disposing at least one heat exchange pad against the external skin of the patient and exchanging heat with the patient using the pad to cool the patient by lowering the body temperature of the patient. The cooling can be done on a febrile patient to maintain normothermia or it can be done to induce therapeutic hypothermia in the patient. The method also includes administering at least one anti-shivering agent to the patient by, e.g., injecting a substance into the bloodstream of the patient. The method may also include diagnosing the patient as having had cardiac arrest or myocardial infarction or stroke, prior to inducing hypothermia.
[0005] In another aspect, a system includes at least one pad that is configured for external placement on the skin of a patient and that is operable to cool the patient to induce hypothermia in the patient. A substrate is associated with the pad and bears instructions to administer an anti-shivering agent to the patient.
[0006] In still another aspect, a method includes providing instructions to a medical practitioner. The instructions include placing a heat exchange pad or pads against the skin of a patient and inducing hypothermia in the patient using the pad or pads. The method also includes countering shivering in the patient.
[0007] The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic view of a non-limiting system in accordance with the present invention; and
[0009] FIG. 2 is a flow chart of a non-limiting method in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0010] Referring initially to FIG. 1 , a system is shown, generally designated 10 , that includes one or more pads 12 that are positioned against the external skin of a patient 14 (only one pad 12 shown for clarity). The pad 12 is any one of the pads disclosed in the external pad patents. A substrate 16 such as a label that is affixed to the pad or an instruction manual that accompanies the pad can also be provided that bears instructions regarding the method set forth herein. In any case, the temperature of the pad 12 can be controlled by a controller 18 in accordance with principles set forth in the external pad patents to exchange heat with the patient 14 , including to establish normothermia in a febrile patient and to induce therapeutic mild or moderate hypothermia in the patient in response to the patient presenting with, e.g., cardiac arrest, myocardial infarction, stroke, high intracranial pressure, traumatic brain injury, or other malady the effects of which can be ameliorated by hypothermia.
[0011] When hypothermia is induced in the patient, the patient may shiver, and it may be desirable to counter the shivering. The patient may be covered by a blanket but more preferably is treated by injecting, into the patient's bloodstream through an intravenous line 20 , one or more anti-shivering substances 22 that can be contained in a source 24 of anti-shivering drugs. The source 24 may be, without limitation, a syringe or IV bag or other source. In non-limiting embodiments the substance 22 may be any one of the substances disclosed in the anti-shivering patents.
[0012] FIG. 2 shows that at block 26 , the patient presents with symptoms that are diagnosed as indicating hypothermia, e.g., the patient may be diagnosed with cardiac arrest, myocardial infarction, stroke, high intracranial pressure, traumatic brain injury, or other malady the effects of which can be ameliorated by hypothermia. At block 28 , the pad 12 is placed on the external skin of the patient, and at block 30 hypothermia is induced in accordance with the external pad patents. However, in accordance with the present invention, instead of allowing the patient to shiver, at block 32 the anti-shivering substance 22 or other therapy (e.g., warming blanket) is administered to the patient to counter the shivering.
[0013] While the particular SYSTEM AND METHOD FOR REDUCING SHIVERING WHEN USING EXTERNAL COOLING PADS as herein shown and described in detail is fully capable of attaining the above-described objects of the invention, it is to be understood that it is the presently preferred embodiment of the present invention and is thus representative of the subject matter which is broadly contemplated by the present invention, that the scope of the present invention fully encompasses other embodiments which may become obvious to those skilled in the art, and that the scope of the present invention is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more”. It is not necessary for a device or method to address each and every problem sought to be solved by the present invention, for it to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. Absent express definitions herein, claim terms are to be given all ordinary and accustomed meanings that are not irreconcilable with the present specification and file history.
|
Heat exchange pads are externally applied to a patient to induce therapeutic hypothermia. Anti-shivering agents may be administered to reduce shivering.
| 0
|
FIELD OF THE INVENTION
[0001] The present invention generally involves a combustor and a method for repairing a combustor. In particular, various embodiments of the present invention provide a system or method for modifying or repairing an end cover in the combustor.
BACKGROUND OF THE INVENTION
[0002] Combustors are known in the art for igniting fuel with air to produce combustion gases having a high temperature and pressure. For example, gas turbine systems, aircraft engines, and numerous other combustion-based systems may include one or more combustors that mix a working fluid, such as air, with fuel and ignite the mixture to produce high temperature and pressure combustion gases. The combustion gases may then be used to rotate a turbine, provide thrust, or perform various other forms of work.
[0003] Each combustor generally includes an end cover and a liner that surround and define a combustion chamber, and the working fluid may flow along the outside of the liner to remove heat from the liner before flowing into the combustion chamber through one or more nozzles. The nozzles may be radially arranged in or connected to the end cover, and fuel may be supplied to the nozzles through the end cover for injection into the combustion chamber. For example, passages through the end cover may connect to complementary passages in the nozzles to provide fluid communication through the end cover and nozzles to the combustion chamber. An insert between the end cover and each nozzle may enable a single end cover design to accommodate several different passages to supply air, fuel, and/or other fluids to the fuel nozzle. The insert may be attached to the end cover by bolts, brazing, or weld joints, and each nozzle may then be bolted or otherwise attached to the insert and/or the end cover to complete the fluid pathway through the end cover, insert, and each nozzle.
[0004] Temperature changes associated with the combustor may produce uneven expansion between the end cover and the insert. Over time, the braze or weld joints between the end cover and the insert may crack or fail, possibly resulting in internal leakage between the various passages in the end cover and/or insert. For some end cover designs, the braze or weld joints may be removed and replaced by one or more seals between the end cover and the insert, as disclosed in U.S. Pat. No. 7,134,287, assigned to the same assignee as the present invention. However, geometric constraints preclude adequate seating surfaces for the replacement seals in some end cover designs. Therefore, a new combustor design that allows for replacement or repair of one or more braze or weld joints in the end cover would be useful.
BRIEF DESCRIPTION OF THE INVENTION
[0005] Aspects and advantages of the invention are set forth below in the following description, or may be obvious from the description, or may be learned through practice of the invention.
[0006] One embodiment of the present invention is a combustor that includes an end cover with a borehole through the end cover. The combustor further includes an insert in the borehole in the end cover and at least one continuous passage through the end cover and the insert. A ring is fixedly connected to the end cover with a seal between the ring and the insert.
[0007] Another embodiment of the present invention is a combustor that includes an end cover and a nozzle connected to the end cover. The combustor further includes an insert between the end cover and the nozzle and at least one continuous passage through the end cover and the insert. A ring is fixedly connected to the end cover with a seal between the ring and the insert.
[0008] The present invention also includes a method for repairing a combustor. The method includes fixedly connecting a ring to an end cover and installing a replacement insert in the end cover. The method further includes installing a seal between the ring and the replacement insert.
[0009] Those of ordinary skill in the art will better appreciate the features and aspects of such embodiments, and others, upon review of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] A full and enabling disclosure of the present invention, including the best mode thereof to one skilled in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:
[0011] FIG. 1 is a simplified cross-section view of a combustor according to one embodiment of the present invention;
[0012] FIG. 2 is an enlarged cross-section view of a portion of the end cover shown in FIG. 1 ;
[0013] FIG. 3 is an enlarged cross-section view of the end cover shown in FIG. 2 with the insert substantially removed;
[0014] FIG. 4 is an enlarged cross-section view of the end cover shown in FIG. 3 with a replacement insert installed in the end cover according to one embodiment of the present invention;
[0015] FIG. 5 is an enlarged cross-section view of the seal shown in FIG. 4 according to one embodiment of the present invention; and
[0016] FIG. 6 is an enlarged cross-section view of the seal shown in FIG. 4 according to an alternate embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] Reference will now be made in detail to present embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the invention.
[0018] Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope or spirit thereof For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
[0019] FIG. 1 shows a simplified cross-section view of a combustor 10 according to one embodiment of the present invention. A casing 12 may surround the combustor 10 to contain the air or working fluid flowing to the combustor 10 . As shown, the combustor 10 may include one or more nozzles 14 radially arranged in a top cap 16 . An end cover 18 and a liner 20 generally surround a combustion chamber 22 located downstream of the nozzles 14 . A flow sleeve 24 with flow holes 26 may surround the liner 20 to define an annular passage 28 between the flow sleeve 24 and the liner 20 . The air or working fluid may pass through the flow holes 26 in the flow sleeve 24 to flow along the outside of the liner 20 to provide film or convective cooling to the liner 20 . The air or working fluid then reverses direction to flow through the one or more nozzles 14 where it mixes with fuel before igniting in the combustion chamber 22 to produce combustion gases having a high temperature and pressure.
[0020] FIG. 2 shows an enlarged cross-section view of a portion of the end cover 18 shown in FIG. 1 before the improvements included in various embodiments of the present invention. As shown, the end cover 18 may include one or more boreholes 30 and continuous passages 32 that extend through the end cover 18 . The boreholes 30 and continuous passages 32 provide fluid communication through the end cover 18 to allow a fuel, a diluent, an inert gas, or other fluid to flow through the end cover 18 to the nozzle 14 . As shown in FIG. 2 , in particular embodiments the borehole 30 may be stepped in the axial direction, resulting in varying diameters of the borehole 30 through the end cover 18 that provide convenient seating surfaces between the end cover 18 and an insert 34 . The insert 34 may be installed in the borehole 30 and connected to the end cover 18 by bolts or one or more braze 36 or weld joints, and the nozzle 14 may be connected to the end cover 18 and/or insert 34 downstream of the insert 34 so that the insert 34 is between the end cover 18 and the nozzle 14 . In this manner, fluids in the borehole 30 and/or passages 32 may flow through the insert 34 to the nozzle 14 , and the braze 36 or weld joints between the insert 34 and the end cover 18 may provide a suitable boundary to prevent co-mingling or mixing of the fluids in the borehole 30 and/or passages 32 .
[0021] During transient or extended operations, temperature gradients between the end cover 18 and the insert 34 may weaken or damage the braze 36 or weld joints between the end cover 18 and the insert 34 . As a result, leaks may develop between the borehole 30 and the passages 32 , allowing co-mingling or mixing of the fluids in the borehole 30 and/or passages 32 . Although the combustor 10 may continue to operate with some amount of leakage between the borehole 30 and various passages 32 , any leakage may compromise the combustor operation by altering the designed fluid flow through the nozzle 14 . The weakened or damaged braze 36 or weld joints may be difficult to inspect and detect, and once detected, the spatial or geometric limitations inside the borehole 30 may make conventional repairs difficult or impractical without replacing the entire end cover 18 . Various embodiments of the present invention provide a system and method for modifying a new or existing end cover 18 that replaces or repairs one or more existing braze 36 or weld joints with a ring 40 . The ring 40 typically has a lower stiffness than the original insert 34 , resulting in lower tensile stresses between the ring 40 and the end cover 18 . In addition, due to the removal or repair of one or more braze 36 or weld joints, the ring 40 may be more accessible to subsequent inspection and repairs, if necessary. As a result, the end cover 18 may be modified or repaired to couple the end cover 18 to the nozzle 14 without requiring a redesigned or replacement end cover 18 , producing substantial savings in repair or replacement costs.
[0022] FIG. 3 provides an enlarged cross-section of the end cover 18 shown in FIG. 2 with the original insert 34 removed. The original insert 34 and any weakened or damaged braze 36 or weld joints may be substantially removed from the borehole 30 , for example by grinding or machining, leaving in place one or more rings 40 from the original insert 34 and associated braze 36 or weld joints that are still functioning. Alternately, as shown in FIG. 3 , the original insert 34 and all associated braze 36 or weld joints may be completely removed and replaced with one or more rings 40 fixedly connected to the end cover 18 . Each ring 40 , whether a remnant from the original insert 34 or a new piece, may comprise a hoop that is brazed or welded to the end cover 18 as before. The reduced mass and open geometry of each ring 40 reduces the stiffness of each ring 40 , resulting in a corresponding reduction in the tensile stress between each ring 40 and the end cover 18 . In addition, each ring 40 provides a convenient surface to mate with a replacement insert 42 while still preserving the continuous passages 32 through the end cover 18 and replacement insert 42 .
[0023] FIG. 4 provides an enlarged cross-section of the end cover 18 shown in FIG. 3 with the replacement insert 42 installed in the end cover 18 according to one embodiment of the present invention. As shown in FIG. 4 , the replacement insert 42 , costing far less than a replacement end cover 18 , may be inserted into the borehole 30 . A seal 44 between each ring 40 and the replacement insert 42 provides a suitable boundary to prevent co-mingling or mixing of the fluids in the borehole 30 and/or passages 32 . The seal 44 may comprise an annular metal ring having a generally W-shaped or C-shaped cross-section that allows the seal 44 to readily flex in response to relative movement between the replacement insert 42 and the associated ring 40 . The nozzle 14 may again be connected to the end cover 18 and/or replacement insert 42 downstream of the replacement insert 42 so that the replacement insert 42 is between the end cover 18 and the nozzle 14 . In this manner, fluids in the borehole 30 and/or passages 32 may flow through the replacement insert 42 to the nozzle 14 as before, and the combination of the rings 40 and seals 44 between the replacement insert 42 and the end cover 18 provide a suitable boundary to prevent co-mingling or mixing of the fluids in the borehole 30 and/or passages 32 .
[0024] FIGS. 5 and 6 provide enlarged cross-sections of the seals 44 shown in FIG. 4 according to various embodiments of the present invention. As shown in FIGS. 5 and 6 , the seals 44 prevent fluid flow across the seals 44 during expansion or contraction of the adjacent surfaces. Specifically, FIG. 5 shows that the W-shaped seal 44 between the ring 40 and the replacement insert 42 allows the ring 40 and the replacement insert 42 to expand or contract during operation without allowing fluid flow across the seal 44 . Similarly, FIG. 6 shows that the C-shaped seal 44 may replace an existing braze or weld joint between the end cover 18 and the replacement insert 42 .
[0025] 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 include 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 languages of the claims.
|
A combustor includes an end cover with a borehole through the end cover. The combustor further includes an insert in the borehole in the end cover and at least one continuous passage through the end cover and the insert. A ring is fixedly connected to the end cover with a seal between the ring and the insert. A method for repairing a combustor includes fixedly connecting a ring to an end cover and installing a replacement insert in the end cover. The method further includes installing a seal between the ring and the replacement insert.
| 5
|
BACKGROUND OF THE INVENTION
The present invention relates to the antimicrobial arts. It finds particular application in conjunction with the reduction of microorganisms on and moisturization of the skin of health care personnel and will be described with particular reference thereto. It should be appreciated, however, that the invention is also applicable outside the medical area, such as a skin conditioning lotion for workers in the food preparation industry, in home health care, or in other areas where skin disinfection and moisturization is desired.
The chemical control of bacteria and viruses is assuming increasing importance in the hospital and medical fields. A wide variety of topical compositions for treatment of the skin are available, including moisturizers, anti-acne compositions, sunscreens, topical anesthetics, artificial tanning compositions, skin lightening compositions, anti-wrinkle compositions, and the like, often in the form of lotions. The most common lotions use anionic, or negatively charged, emulsifiers to stabilize the composition. These lotions have no antimicrobial activity and are used for moisturization only. Nonionic emulsifier-based lotions can also be made, however these tend to be low viscosity fluids.
Lotions are also available which are compatible with an antimicrobial residue left behind on the skin after washing or rinsing with an antimicrobial-containing product. However, these antimicrobial wash products are not themselves moisturizing and are therefore used prior to separate moisturizing product. The antimicrobial wash product is not left on the skin but is washed off prior to the application of the moisturizers. Such antimicrobial wash products would be harsh to the skin if utilized repeatedly in leave-on applications.
Lotions have been developed which provide antimicrobial activity to destroy microorganisms, such as bacteria, on the surface of the skin, while also providing a moisturizing function. Several leave-on products have been developed including those which contain triclosan as the active ingredient. These tend to be relatively ineffective at reducing the antimicrobial population on the skin.
Alcohol-containing products, which include chlorhexidine, are also known. Such compositions use both alcohol and chlorhexidine for quick and persistent activity. However, the alcohol tends to be drying to the skin. Those formulas which also contain emollients to counteract this drying effect tend have a reduced moisturizing effect on the dry skin. Additionally, these products are not actually lotions (stable oil-in-water emulsions) but function as a gel in which the antimicrobial agent is dispersed throughout the composition.
The present invention provides a new and improved skin care composition and method of use which overcomes the above-referenced problems and others.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, an oil-in-water emulsion for antimicrobial skin treatment is provided. The composition includes a nonionic emulsifier, an anionic emulsifier, a cationic antimicrobial agent, a carrier oil, and water.
In accordance with another aspect of the present invention, a fast acting antimicrobial lotion is provided. The lotion includes, as a percent by weight, 0.25-8.0% of a nonionic emulsifier, 0.1-2.0% of an anionic emulsifier, 0.5-10.0% of a thickener, 0-15.0 % of a humectant, 0.02-5.0% of a skin conditioner, 2.0-20.0% of an oil, 0.25-5% of a cationic antimicrobial agent, and water.
One advantage of the present invention is that the skin is microbially decontaminated and moisturized in a single application.
Another advantage of the present invention is that the composition is fast-acting.
Yet another advantage of the present invention is that it avoids the use of substantial quantities of alcohol in the composition, which tends to be drying to the skin.
Yet another advantage of the present invention is that it provides equivalent antimicrobial activity to conventional cationic antimicrobial containing wash products at substantially lower concentrations of the active ingredient.
Another advantage of the present invention is that it enables the viscosity of the composition to be increased to a level which retains the antimicrobial on the skin for an extended period of time.
Yet another advantage of the present invention is that the composition need not be removed from the skin as it is moisturizing and nondrying.
Still further 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.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A skin care composition which provides antimicrobial activity while moisturizing the skin is provided. The composition may be used in place of hand washing, as an adjunct to hand washing, as a surgical scrub, or as a surgical preoperative skin preparation. The composition is preferably used as a leave-on composition, which is applied to the skin and left in place to provide both immediate and long term antimicrobial activity and moisturizing functions. While use of the composition is described with reference to application to skin, particularly human skin, the composition may also be used for treatment of hair, scalp, and on animals.
By antimicrobial activity, it is meant that the composition reduces the number of viable microorganisms on the skin, primarily by inactivating or killing the microorganisms, rather than by physically removing them.
The skin care composition comprises an oil-in-water emulsion which includes an antimicrobial agent, preferably a cationic antimicrobial agent. By oil-in-water emulsion, it is meant that the composition is formulated to have a discontinuous oil phase that is dispersed in a water, i.e., the aqueous phase. Specifically, a fine dispersion of oil phase droplets is held in the surrounding water phase by suitable emulsifiers. In the present case, the formulation maintains the antimicrobial agent primarily in the external phase (water) rather than in the internal phase (oil). This allows the antimicrobial to be more readily available and increases the rate of kill of microorganisms. This is in contrast to prior compositions, in which a large portion of the active is found in the internal phase, where it is unavailable for immediate activity on the skin.
The oil in water emulsion comprises an aqueous phase at from about 40% to about 95% by weight of the total composition. Preferably, the compositions includes from about 60 to about 80% by weight of an aqueous phase, in which the oil phase is dispersed.
Emulsifier System
The composition includes a combination of at least one anionic emulsifier and at least one nonionic emulsifier, the nonionic emulsifier(s) preferably being at a higher concentration than the anionic emulsifier(s). It has been found that a combination of anionic and nonionic emulsifiers provides better stability to the emulsion, while simultaneously providing unexpectedly better antimicrobial activity. While a single emulsifier may be used, the microbial activity and physical stability are generally significantly reduced.
The preferred emulsifiers are surfactants which are non-foaming, and thus differ from the conventional high-foaming surfactants used in wash-off compositions. Additionally the concentration of the emulsifiers is less than that used in wash-off compositions, which typically use significantly greater than 5% total surfactants. Specifically, the emulsifiers of the present composition are preferably used in a sufficient amount to just coat the surface area of all of the oil droplets. However, if too much emulsifier is used, it tends to move into the water phase, where it binds and micellizes the chlorhexidine gluconate or other antimicrobial agent, reducing its antimicrobial activity. If too little emulsifier is used, the oil droplets are not fully coated and the chlorhexidine gluconate tends to attach to the surfaces of the oil droplets, also leading to reduced antimicrobial activity. Consequently, the optimal amount of emulsifier used depends on the total amount of oil and type of oil used in the composition. The optimal amount can be determined by efficacy studies in which the concentration of emulsifier is varied and the antimicrobial efficacy is measured. A plot of efficacy against emulsifier concentration shows a peak at the optimal concentration. When cyclomethicone or similar simethicone is used as the oil at a concentration of about 5-12 weight percent, the total emulsifier content is preferably less than about 5 wt. %, more preferably between 1 and 5%, i.e., an oil to surfactant ratio of about 2.5:1 or higher.
To avoid micellization of the antimicrobial agent, it is preferable to add the antimicrobial agent after forming the oil-in-water emulsion.
Nonionic Emulsifier
It has been found that by using an appropriate amount of a nonionic emulsifier, the cationic antimicrobial agent can be maintained primarily in the water phase. This makes the antimicrobial more available, i.e., more effective at decontaminating the skin surface in a reduced time frame. The nonionic emulsifier is preferably present in the composition at a concentration of from 0.25%-8% by weight, more preferably, from about 1% to about 5% by weight.
Exemplary nonionic emulsifiers include polyoxyethylene alcohols and glycol fatty acid esters with an ethoxylation range of 2-100 mols, suitable fatty alcohol groups including lauryl, cetyl, cetearyl, oleyl, and tridecyl. Examples of glycol fatty acid esters include ceteareth-10, laureth-4, and the like. Other nonionic emulsifiers include fatty acid esters of sorbitan and polyoxyethylene sorbitan, polyoxyethylene fatty acid esters, quaternary amine salts of fatty acids, phospholipid complexes/emulsifiers, polyol fatty acid esters, and polymeric surfactants. Examples include Hypermer's, a polymeric surfactant obtained from ICI America, PEG-X soya sterol oil and the diethanolamine salt of cetyl phosphate. The nonionic emulsifier may be a combination of two or more emulsifiers.
Preferred nonionic emulsifiers are C 12 -C 22 ethoxylated fatty alcohols, particularly glycol fatty acid esters such as stearyl ethers characterized by the CTFA designation as Steareth X, where X is from 2 to 100 mols ethoxylation. Examples include Steareth-2, Steareth-10, Steareth 21, Steareth-100. A combination of two or more of the Steareth compounds is particularly preferred, to provide a hydrophobic lipophilic balance (HLB) which maintains the oil-in-water emulsion. A suitable HLB number for the system is from about 10-20, more preferably 10-15, most preferably, about 12.5. Of course, other components of the composition, such as cyclomethicone, also contribute to the overall desired HLB.
For example, a combination of Steareth X 1 and Steareth X 2 may be used, where X 1 is from 2 to 10 mols ethoxylation, and X 2 is from 11 to 100 moles ethoxylation.
Anionic Emulsifier
The anionic emulsifier is preferably present in the composition at a concentration of 0.1-2.0% by weight, more preferably, at a concentration of 0.1-0.75% by weight.
Suitable anionic emulsifiers are of the general formula RCO(OCHCH 3 CO) n O − X + , where R is a long chain aliphatic group, such as caproyl, lauroyl, stearoyl, n is an integer, principally 1 or 2, and X is a cation (such as Na + , Ca + , K + , NH 4 + , or alkanolamine, e.g., triethanolamine). The alkyl group of the fatty acid preferably has from 6-22 carbons, such as caproyl, isostearoyl, cocoyl, hydroxystearoyl, behenoyl, stearoyl, and the like. Exemplary anionic emulsifiers of this type include cationic salts of esters of lactyl lactylates, such as potassium, sodium, triethanolamine, and calcium salts of lauroyl lactylate, cocoyl lactylate, stearoyl lactylate, and caproyl lactylate.
Preferred emulsifiers are low foaming. A particularly preferred anionic emulsifier is a salt of lauroyl lactylate, such as sodium lauroyl lactylate.
The Water Phase
Antimicrobial Agent
The composition includes a safe and effective amount of at least one active antimicrobial ingredient. The term “safe and effective amount,” as used herein, means an amount which is safe for use on human skin, and which is sufficient to bring about a desired level of microbial decontamination. This level may be complete sterilization, or some lesser level of microbial decontamination, such as disinfection or sanitization. The exact amount will depend on the agent selected, the desired level of antimicrobial activity, the amount of the composition to be applied, the exposure time, viscosity, and other factors.
The composition preferably includes a cationic antimicrobial as the active ingredient. Suitable cationic antimicrobials include salts of chlorhexidine, such as chlorhexidene digluconate, chlorhexidene acetate, chlorhexidene isethionate, chlorhexidene hydrochloride. Other cationic antimicrobials may also be used, such as benzalkonium chloride, benzethonium chloride, polyhexamethylene biguanide, cetyl puridium chloride, methyl and benzothonium chloride.
Salts of chlorhexidine, in particular, chlorhexidene digluconate, are particularly preferred antimicrobials. A combination of cationic antimicrobials may be used. Cationic antimicrobials in the past have not been used in combination with anionic surfactants as they are generally considered to be incompatible.
The cationic antimicrobial agent is present in a sufficient amount to microbially decontaminate the skin of the user. For salts of chlorhexidine, such as chlorhexidine gluconate, a preferred concentration is from 0.25 to 5% by weight, more preferably, from about 0.5 to about 4% by weight of the composition.
Other antimicrobials may also be used, alone or in age combination with a cationic antimicrobial agent as previously described. These include halogenated phenolic compounds, such as 2,4,4′,-trichloro-2-hydroxy diphenyl ether (Triclosan); parachlorometa xylenol (PCMX); and short chain alcohols, such as ethanol, propanol, and the like. For example, a combination of chlorhexidine gluconate and ethanol may be used. However, the alcohol is preferably at a low concentration (below about 10% by weight of the composition and, more preferably, below 5% by weight) so that it does not cause undue drying of the skin.
Humectants (Cosolvents)
A humectant is preferably present in the composition at a concentration of from 2-15% by weight, more preferably, from 2-10% by weight. The humectant is a water soluble component, i.e., it is primarily present in the aqueous phase. The humectant used herein provide stability to the water phase, however it may also provide other functions, such as promotion of water retention by the skin or hair, emolliency, and other moisturizing or conditioning functions.
Suitable humectants are polyhydric alcohols, such as C 3 -C 6 diols and triols, and polyethylene glycols. These act as cosolvents and help to stabilize the water phase. Examples include propylene glycol, dipropyleneglycol, hexylene glycol, 1,4-dihydroxyhexane, 1,2,6-hexanetriol, sorbitol, butylene glycol, propanediols, such as methyl propane diol, dipropylene glycol, triethylene glycol, glycerin (glycerol), polyethylene glycols, ethoxydiglycol, polyethylene sorbitol, and combinations thereof. Other humectants include glycolic acid, glycolate salts, lactate salts, lactic acid, sodium pyrrolidone carboxylic acid, hyaluronic acid, chitin, and the like.
Particularly preferred as humectants are propylene glycol and glycerin. These have been found to have a positive effect on both the moisturizing function and the antimicrobial activity of the composition.
Other cosolvents include alcohols, such as ethanol, n-propanol, and isopropanol; triglycerides; ethyl acetate; acetone; triacetin; and combinations of these.
Skin Conditioner/Emollient
The composition may also include a skin conditioner/emollient at a concentration of from 0.02-5% by weight, more preferably, from about 0.05 to about 2% by weight. Exact levels of emollient will depend upon the material chosen with consideration being given to the effects upon the composition.
Emollients in skin and personal care compositions are materials which are used to replace or add lipids and natural oils in the skin or hair. The emollient materials help to provide a skin conditioning benefit, moisturizing the skin by depositing on the skin or hair during the application process.
Suitable skin conditioners include quaternary ammonium salts of acrylamide and dimethyl diallyl ammonium chloride (DIMDAC) polymers, such as Polyquaternium-6, Polyquaternium-7 and Polyquaternium-10. Also useful are nonvolatile silicones, such as polydialkylsiloxanes, polydiarylsiloxanes, and polydialkarylsiloxanes. Polyalkyl siloxanes have the general formula R 3 SiO[R 2 SiO] x SiR 3 , where R 2 and R 3 independently are an alkyl group, such as methyl or ethyl, and x is an integer up to about 500, chosen to achieve the desired molecular weight. Commercially available polyalkylsiloxanes include polydimethylsiloxanes, also known as dimethicones. Useful polyalkylaryl siloxanes include polymethylphenyl siloxanes.
Also useful are dimethiconols, which are hydroxy-terminated dialkyl silicones, such as dimethyl silicones. These materials may be represented by the general formulae R 4 SiO[R 5 2 SiO] x SiR 6 OH and HOR 7 SiO[R 8 SiO] x SiR 9 OH, wherein R 4 -R 9 are independently an alkyl group, preferably methyl or ethyl; and x is an integer up to about 500, chosen to achieve the desired molecular weight.
Other useful skin conditioners are silicone polyethers; alkyl methyl silicones; C 8 -C 30 alkyl esters of C 8 -C 30 carboxylic acids; C 1 -C 6 diol monoesters and diesters of C 8 -C 30 carboxylic acids; cholesterol esters of C 8 -C 30 carboxylic acids; monoglycerides, diglycerides, and triglycerides of C 8 -C 30 carboxylic acids; polyethylene glycol derivatives of vegetable glyceride; hydrocarbon oils or waxes, and silicone gum/resin blends. Examples of these materials include diisopropyl adipate, isopropyl myristate, isopropyl palmitate, palm kernel glyceride, caprylic glyceride, capric glyceride, glyceryl cocoate, C 12 -C 15 alkyl benzoates; PPG-15 stearyl ether benzoates; dipropylene glycol benzoate; cetyl esters; chitosan; cetyl lactate; PEG-60 corn glyceride; PEG-45 palm kernel glyceride; pentaerythrityl tetraisostearate; hydrogenated polybutenes; polyisobutene; aloe vera (which also serves as a humectant); vitamin E; mucopolysaccharides; (hydrogenated) 1-decene homopolymers; steroid alcohols; and combinations thereof. Other useful skin conditioners include sorbitan laurate, lanolin, lanolin esters, alkoxylated and/or polyoxylated C 3 -C 6 diols and triols, ethoxylated and propoxylated sugars, such as mannitol, and the like.
Among the skin conditioners preferred are Polyquaternium salts, dimethicone, dimethiconol, cetyl esters, glyceryl esters of fatty acids, particularly palm kernel glyceride, caprylic glyceride, and capric glyceride, glyceryl cocoate, C 12 -C 15 alkyl benzoates, dipropylene glycol benzoate, PPG 15 stearyl ether benzoate, chitosan, and cetyl lactate. Polyquaternium salts, such as Polyquaternium-7, are particularly preferred skin conditioners. They may be purchased from Calgon Chemical as 8% or 40% solutions.
Thickener
The water phase is preferably thickened with a thickening agent to provide the composition with a suitable viscosity to keep the composition in contact with the skin for an extended period. The thickening agent is one which is compatible with cationic actives, such as chlorhexidine gluconate.
Suitable thickeners (which in some cases may also contribute some emulsification properties) include alcohols, such as cetyl, stearyl, cetostearyl, caprylic, myristyl, decyl, lauryl, and oleyl alcohol; emulsifying waxes, such as Emulsifying Wax NF (a cetostearyl alcohol plus polyoxyethylene derivative of a fatty acid ester of sorbitan; fatty acid esters, such as monoesters of a fatty acid and glycerine; and mono or di esters of fatty acids and glycol. Examples of fatty acid esters include glyceryl stearate, glyceryl oleate, glyceryl palmitate. Examples of mono and di esters of fatty acids and glycol include glycol stearate, glycol dilaurate, glycol hydroxystearate, and glycol distearate.
Polymeric thickeners may also be used, such as hydroxymethyl cellulose, hydroxyethyl cellulose, cetyl hydroxymethyl cellulose, guar gum, and the like. Polyethylene glycols may also be used, preferably those having a weight average molecular weight (M W) range of from about 400 to about 4000.
Cetyl alcohol is particularly preferred thickener since it also acts as an emulsifier and an emollient.
The concentration of the thickener depends on the selected thickener and the desired viscosity. A preferred viscosity is at least about 1000 cps. In the case of cetyl alcohol, the concentration is preferably from 0.5-10%, more preferably, from about 0.5 to about 6% by weight of the composition.
Water
The balance of the aqueous phase is water. The composition includes from about 35% to about 90% water, more preferably, from about 60% to about 85% water. The exact level of water depends on the desired levels of the various components and any other additives employed.
The Oil Phase
Carrier
The oil phase comprises one or more oils or oil phase component (all generally referred to herein as “carrier oils”), which acts as a carrier for the oil phase.
The carrier oil is present in the composition preferably at a concentration of 2-20% by weight, more preferably, from about 5 to 12% by weight.
Suitable carrier oils include volatile silicones, such as cyclomethicone, dimethicone; siloxanes, such as tetra, penta, or hexa cyclosiloxane, hexamethyl disiloxane, and octyltrisiloxane.
Preferred are volatile silicones, such as cyclomethicone. These silicones act as an emollient, in addition to a carrier, and provide lubricity to the composition. Cyclomethicone is a particularly preferred carrier. It is a non-greasy volatile silicone, which dissipates when rubbed in to the skin.
The Preferred Compositions
A preferred composition includes:
% by weight of
Component
active indredient
Nonionic Emulsifier
0.25-8.0
Anionic Emulsifier
0.1-2.0
Thickener
0.5-10.0
Humectant
0-15.0
Skin Conditioner
0.02-5.0
Carrier
2.0-20.0
Antimicrobial Agent
0.25-5
A particular preferred composition includes:
% by weight of
Component
active ingredient
Nonionic Emulsifier
1.0-5.0
(Two or more Steareth compounds)
Anionic Emulsifier
0.1-0.75
(lactylate)
Thickener
0.5-6.0
(fatty alcohol)
Humectant
2.0-10.0
(polyhydric alcohol)
Skin Conditioner
0.02-2.0
(Polyquaternium)
Carrier
5.0-12.0
(cyclomethicone)
Antimicrobial Agent
0.5-4.0
(chlorhexidine digluconate)
The chlorhexidine gluconate:nonionic emulsifier ratio is from about 1:5 to about 1:1, the optimal amount depending on the amount of the internal (oil) phase.
Other additives
The composition of the present invention can also comprise a wide range of other additional components. The CTFA Cosmetic Ingredient Handbook , Second Edition, 1992, describes a wide variety of nonlimiting cosmetic and pharmaceutical ingredients commonly used in the skin care industry, which are suitable for use in the compositions of the present invention. Examples of functional classes of additional components include: absorbents, abrasives, anti-acne agents, anticaking agents, antifoaming agents, antioxidants, binders, biological additives, buffering agents, bulking agents, chelating agents, chemical additives, colorants, cosmetic astringents, cosmetic biocides, denaturants, drug astringents, external analgesics, film formers, fragrance components, humectants, opacifying agents, pH adjusters, plasticizers, preservatives, propellants, reducing agents, skin protectants, solvents, suspending agents (nonsurfactant), ultraviolet light absorbers, and viscosity increasing agents (aqueous and nonaqueous). Examples of other functional classes of materials useful herein that are well known to one of ordinary skill in the art include emulsifiers, solubilizing agents, and sequestrants, and the like.
Nonlimiting examples of these additional components cited in the CTFA Cosmetic Ingredient Handbook , as well as other materials useful herein, include the following: vitamins and derivatives thereof [e.g., vitamin C, tocopherol, tocopherol acetate, and the like]; anti-oxidants; polyethyleneglycols and polypropyleneglycols; preservatives for maintaining the antimicrobial integrity of the composition; antioxidants; chelators and sequestrants; and aesthetic components such as fragrances, pigments, colorings, essential oils, and the like.
The composition can be formulated in a number of ways. In one method, a two vessel process is used. The water insoluble components are mixed together in one vessel, while the water soluble components are mixed in another. Heat is optionally applied to melt any solid components, a temperature of about 65° C. being suitable in most instances. The contents of the two vessels are then combined (preferably at the same temperature) and thoroughly mixed to provide an emulsion. Preferably, the antimicrobial agent is added at a temperature at which it is not subject to inactivation. For example, chlorhexidine salts are preferably added to the emulsion after cooling to below 50° C.
In another method, a single vessel is used. The water and other components, with the exception of the cyclomethicone (or other carrier oil) and antimicrobial agent, are heated in the vessel to a temperature slightly above, e.g., about 50° C. above, the highest melting temperature of the components present (typically approximately 65° C.) and mixed thoroughly. The mixture is then cooled to below about 50° C. and the cyclomethicone added and mixed with the other components. After mixing, the antimicrobial agent is added.
Other methods of combining the ingredients into an oil in water emulsion are also contemplated.
The composition may be dispensed from a bottle, tube, spray, wipe, or other suitable dispenser. Preferably, it is applied directly to the skin and rubbed in for few seconds to a minute. It may be applied neat or diluted, ether by hand or with a cloth or other applicator. The amount applied can vary although it is preferably applied in a pharmaceutically acceptable amount, i.e., one which is sufficient to achieve a desired level of antimicrobial activity and moisturizing effect without harmful results to the skin. The skin is decontaminated within about one minute. Leaving the composition on the skin allows continued moisturizing and antimicrobial effect for several hours or more. For example, the composition may be applied to a patients' skin up to about 12 hours before a surgical procedure is to take place.
The invention is further illustrated by the following examples, without intending to limit the scope of the invention.
EXAMPLES
Example 1
Formulation for Antimicrobial Lotion
An antimicrobial lotion which is fast acting yet moisturizing to the skin was prepared according to the formulation in TABLE 1. The concentration of the 20% chlorhexidine digluconate (CHG) solution and water was adjusted slightly, based on activity level of the CHG solution.
TABLE 1
Ingredient
%
Function
Deionized Water
71.065
External phase
Steareth-2
0.595
Nonionic Emulsifier
Steareth-100
0.540
Nonionic emulsifier
Steareth-10
0.250
Nonionic Emulsifier
Sodium lauroyl lactylate
0.200
Anionic Emulsifier/emollient
Dimethicone - 1000
0.250
Skin conditioner
centistokes, NF
Glycerine
7.000
Humectant
Emulsifying Wax, NF
4.000
Emulsifier/Emollient/
(cetostearyl alcohol)
Thickener
Cetyl alcohol
0.500
Emulsifier/Emollient/
Thickener
Polyquaternium-7
0.500
Skin Conditioner
Emollient/Carrier/
Cyclomethicone
10.000
Lubricity
Chlorhexidine digluconate
5.0
Active ingredient-
(20%)
(1.0%
Antimicrobial
active)
Fragrance
0.100
Fragrance
A single vessel was used to prepare the composition. The water and other components, with the exception of the cyclomethicone and chlorhexidine digluconate, were heated in the vessel to a temperature of about 65° C. (i.e., above the highest melting temperature of the components present) and mixed thoroughly. The mixture was then cooled to below about 50° C. and the cyclomethicone added and mixed with the other components. After mixing, the chlorhexidine digluconate was added.
Example 2
Formulation for Antimicrobial Lotion
An antimicrobial lotion which is fast acting yet moisturizing to the skin was prepared according to the formulation in TABLE 2 using the method of EXAMPLE 1. The lotion had a higher level of chlorhexidine gluconate (1.5% CHG) than the lotion of Example 1 (1% CHG). The concentration of the 20% CHG solution and water was adjusted slightly, based on activity level of the CHG solution.
TABLE 2
Ingredient
%
Function
Deionized Water
73.925
Steareth-21
0.935
Nonionic Emulsifier
Steareth-10
0.440
Nonionic Emulsifier
Sodium lauroyl lactylate
0.200
Anionic Emulsifier/emollient
propylene glycol
3.500
Humectant
Cetyl alcohol
3.000
Emulsifier/Emollient
Thickener
polyquaternium-7
0.500
Skin Conditioner
Cyclomethicone
10.000
Emollient/Carrier/
Lubricity
Chlorhexidine
7.50
Active
digluconate (20%)
(1.50%
active)
Example 3
Formulation for Antimicrobial Lotion
An antimicrobial lotion was prepared according to the formulation in TABLE 3 using the method of EXAMPLE 1. The lotion had a higher level of chlorhexidine gluconate (1.5%) than the lotion of EXAMPLE 1. The concentration of the 20% CHG solution and water was adjusted slightly, based on activity level of the CHG solution.
TABLE 3
Ingredient
%
Function
Deionized Water
68.565
External phase
Steareth-2
0.595
Nonionic Emulsifier
Steareth-100
0.540
Nonionic emulsif ier
Steareth-10
0.250
Nonionic Emulsifier
Sodium lauroyl lactylate
0.200
Anionic Emulsifier/emollient
Dimethicone - 1000
0.250
Skin conditioner
centistokes, NF
Glycerine
7.000
Humectant
Emulsifying Wax, NF
4.000
Emulsifier/Emollient/
(cetostearyl alcohol)
Thickener
Cetyl alcohol
0.500
Emulsifier/Emollient/
Thickener
Polyquaternium
0.500
Skin Conditioner
Cyclomethicone
10.000
Emollient/Carrier/
Lubricity
Fragrance
0.100
Fragrance
Chlorhexidine digluconate
7.5% (1.5%
Active
(20%)
active)
Example 4
Results for Healthcare Personnel Handwash Clinical Study ( Serratia marcescens ATCC 14756)
The products of Examples 1-3 were tested according to ASTM method E 11747. The results were compared with those for a commercial chlorhexidine digluconate skin wash formulation, Hibiclens™. The test involved applying 5ml of a bacterial suspension of Serratia marcescens to the skin and then applying the selected lotion or wash product. In the case of the lotions of Examples 1-3, the lotion was applied to the skin and rubbed for 90 seconds, prior to conducting the first wash (a 15 second rinse under water). In normal use, the lotions would typically be left on the skin for longer times prior to washing. In the case of the Hibiclens, the label instructions for application were followed. These call for a 15 second application period, in which the product was rubbed into the skin, followed by a 15 second rinse under water. TABLE 4 compares the results after several washes, with n being the number of subjects tested. The results are expressed as log reductions from the baseline value (initial value), a log reduction of 1 indicating a 90% reduction in viable microorganisms and a log reduction of 6 indicating only 1 viable microorganism out of every million microorganisms remains.
TABLE 4
Product
n
Wash 1
Wash 3
Wash 7
Wash 10
Example 1
6
2.66
3.46
3.78
4.18
Example 2
6
3.80
5.10
5.61
5.54
Example 3
6
4.00
4.91
5.17
5.60
Hibiclens
6
3.90
3.43
3.88
3.99
(4% CHG)
The results show that for the products of EXAMPLES 1 to 3, efficacy increases with percentage concentration of CHG (higher log reductions). However, all of the products performed as well as, or better than the 4% wash product (Hibiclens), even when the amount of CHG was only 1%. This shows that effective lotions which retain their efficacy after repeated washes can be prepared without the need for high concentrations of antimicrobial.
The invention has been described with reference to the preferred embodiment. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
|
An antimicrobial lotion for topical use comprises an oil-in-water emulsion with a dispersant of emollient droplets in an oil phase and an antimicrobial agent in a water phase. The emollients moisturize the skin. Antimicrobial agents have a more rapid antimicrobial effect in an aqueous solution than in the oil phase. A combination of anionic and nonanionic surfactants stabilize the emulsion and maintain a cationic antimicrobial agent primarily in the water phase. The resulting lotion is gentle on the skin while providing more rapid antimicrobial effect than conventional lotions. With longer lasting antimicrobial agents, such as chlorhexidene, the lotion is rubbed into the skin and left on to continue moisturizing and killing microbes for up to 12 hours.
| 0
|
This application is a continuation of application Ser. No. 234,429, filed Feb. 13, 1981.
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor unit of the type including at least two semiconductor elements which are fastened in a housing to a metallic base plate in an electrically insulated and thermally conductive manner and provided with current conductor members which also form current terminals and which are contacted under the influence of pressure exerted by spring bodies.
German Utility Model Patent No. 7,512,573 discloses a semiconductor rectifier arrangement in which two semiconductor rectifier elements are fastened in electrical series connection, with their connecting components electrically insulated and thermally conductive to one side of a metallic base plate. The arrangement is embedded in an insulating mass in a plastic housing. The rectifier elements are connected together by a connecting conductor designed to form a third current conduction terminal in line with the other two current conduction terminals and located at one end of the resulting row of three current conduction terminals. The outermost current conduction terminals in said row each are fastened to the associated rectifier element on a conducting layer and, via this layer and an insulating intermediate disc, together to the base plate.
Other prior art semiconductor rectifier arrangements are provided with rectifier elements which are pressure contacted in recesses of the housing and are encased in an insulating mass.
These prior art units have various drawbacks. For example, solder contacting of the rectifier elements is a complicated procedure. When the elements are pressure contacted and embedded in an insulating mass, the rigid encapsulation of the contacting system, which is intended to exhibit an elastic behavior during use, makes the structure susceptible to malfunction. Moreover, the process steps of soldering or encapsulating in the insulating mass, respectively, may adversely influence the electrical properties. Additionally, mechanical stresses due to differences in thermal expansion of adjacent materials frequently result in a reduction of quality. If the parameters of one or more rectifier elements should deteriorate, there is no chance for replacement so that the arrangement must be downgraded regarding its parameters or becomes unusable.
Moreover, none of the prior art structures meets the demands of manufacturers who wish to repeatedly monitor the assembly stages without having to destroy semifinished arrangements and to be able to consider technically relevant factors in a desired manner. None of the prior art embodiments provides a design with selectable electrical orientation of the semiconductor elements. Finally, rectifier arrangements with current conducting terminals arranged in a row cannot always be used universally since they are limited to only one connecting plane.
SUMMARY OF THE INVENTION
Objects of the present invention are to avoid the above-mentioned drawbacks and to provide a semiconductor unit structure which permits more economical manufacture than the prior art devices with complete monitoring of all process stages without damage, to eliminate undesirable mechanical stresses on components, and to permit any desired electrical polarization of the semiconductor devices and universal use thereof.
The above and other objects are achieved, according to the invention, in a semiconductor unit composed of at least two semiconductor members each having two opposed ends and provided at each end with a respective current contact, a housing including a metallic base plate and a cover, means for mounting the semiconductor members in electrically insulated and thermally conductive communication with the base plate, external connecting leads, and spring means for establishing pressure contact between the leads and the current contacts, in that: the connecting leads include a lower lead in the form of a contact rail contacting the current contact at that end of each member which is directed toward the base plate and interposed between the base plate and the members; the contact rail includes a free end region which extends through an opening in the housing to provide an external connection in a selected connection plane; the connecting leads further include an upper lead for each member arranged concentrically with its respective member and contacting the current contact at that end of its associated member which is directed toward the cover; the cover is provided with an opening for each upper lead through which the upper leads extend to provide further external connections; and the unit further includes means securing each upper lead against rotation relative to the housing. Advantageously, mutually coinciding contactable semiconductor elements can be provided, for example those which are encapsulated in the form of discs, i.e. so-called press packs.
The semiconductor devices can also be constructed in such a way that the contact plates resting against the semiconductor body are disposed in a recess in the interior of the frame of the housing, which includes a metallic base plate as well as a frame and a cover of insulating material, the contact plates forming, in this recess, a tight seal for the semiconductor body with the aid of sealing rings.
According to the intended use, the component stacks may be arranged next to one another on a common contact rail and be electrically connected together via this rail, or each component stack may have its own associated contact rail.
In order to determine different switching planes for universal use, the components forming the respective upper connecting leads of the semiconductor elements are brought through an opening in the cover of the housing and form a first switching plane, and the free end of the contact rail is brought out of the housing parallel to the bottom plate to form the second switching plane. For this purpose, the free end of the contact rail may be disposed at a narrow side of the housing, the current terminals then preferably being arranged in a row, or at a long side of the housing. However, the free ends for the contact rails intended for separate wiring of the component stacks may also protrude separately from different sides of the housing or together from one long side of the housing.
The pressure contact system includes a pressure plate which acts together on all component stacks and, for each component stack, at least one spring element, a metallic pressure disc, a body of insulating material which electrically insulates the upper connecting lead against the pressure generating components, and screw elements.
For pressure contacting, the component stacks are pressed onto the contact rail by means of the pressure plate and the screw elements and are releasably fixed thereby to the bottom plate.
The upper connecting lead of each semiconductor element in the stack and the body of insulating material surrounding it are given a rotation-preventing configuration at their mutually adjacent sections and the body of insulating material is additionally provided with a projection that rests against a fastened component to inhibit rotation of the insulating material. For example, the adjacent sections may be designed to have coinciding polygonal shapes and be arranged to mutually interengage.
Special shapes are provided for the housing frame in order to accommodate the components and fix their position within the housing frame as well as for fastening them to the bottom plate. For example, the housing frame is provided on one side with a terminating plate provided with openings to receive the component stacks and to pass through the screw elements, the latter serving to releasably fixedly attach the frame together with the component stacks to the bottom plate.
In another embodiment, the housing frame is provided with sections having an increased wall thickness which contain at least one bore for separately fastening the frame to the bottom plate.
A further embodiment of the housing frame is provided with sections having a greater wall thickness and provided with matching bores for guiding the screw elements. However, the housing frame may also be formed of a massive body which is then provided with recesses for receiving the stacks of components and the contact rail, as well as with bores for passage of the screw elements. The correct positioning of the component stacks can also be realized by rib-shaped configurations in the interior of the housing frame.
Instead of special configurations within the housing frame, the correct position in the arrangement of the component stacks can also be realized by spacer elements which are provided between the housing frame and the component stacks. Preferably, the spacer elements are provided with bores for guiding the screw elements.
To reinforce the mechanical stability of the free end of the contact rail during the connection with current conductors, this free end can be designed as a longitudinal profile having at least one arm. The opening provided for passing this free end through the housing is then given a shape which is adapted to receive the longitudinal profile. The cover of insulating material which closes the housing frame is fastened on the pressure plate.
If controllable semiconductor devices are used, it is advantageous to provide a conductor plate for fastening the control lines and for bringing them through the housing, the conductor plate being disposed between the pressure plate and the housing cover.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational, partly cross-sectional, exploded view of a preferred embodiment of a semiconductor unit according to the invention.
FIGS. 2a-2c are plan views illustrating several preferred embodiments of housing frames and associated components according to the invention.
FIG. 3 is an elevational view, partly in cross section, showing one form of semiconductor device used in embodiments of the invention.
In the various Figures, identical parts are identified by the same reference numerals.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows, partially in cross section, the structure of one preferred semiconductor unit. According to FIG. 1, the carrier for the semiconductor unit is a bottom plate 1 of metal having a high heat conductivity, plate 1 having, for example, a rectangular outline and being provided with planar contact faces. It is provided with threaded bores 11 for fastening the semiconductor devices and their contact components as well as with threaded bores 12 for fastening a housing frame 3. The upper surface of the bottom plate 1 contains continuous, annular groove-like recesses 15 each enclosing a planar surface section 18 on which a stack of components can be placed. The recesses 15 serve to assure the required creep path between current conducting members and the bottom plate against which they are electrically insulated. The surface sections 18 may also be formed by flat-topped raised portions on the bottom plate surface.
A disc of insulating material 2 is placed onto each surface section 18 to provide an electrically insulated but thermally conductive arrangement for a respective stack of components on the bottom plate 1. A correspondingly dimensioned disc 2 of insulating material also serves to provide the necessary insulating distance between the bottom plate 1 and the stack of components. Only one disc 2 may be used to cover all surface sections 18, otherwise each section may be covered by a separate disc.
A continuous, essentially strip-shaped contact rail 51 extends across and bears against the insulating discs 2. The dimensions of the contact rail 51 depend on the form and dimensions of the associated contact faces of the adjacent components and on the desired current carrying capability of the unit. The contact rail 51 forms one connecting lead for each of the semiconductor elements in the interior of the housing as well as their joint current terminal. The section 511 of the contact rail 51 forms the connecting lead which connects the semiconductor elements 4 together; the section 512 is the connecting piece between the connecting lead of the semiconductor elements in the interior of the housing and the current terminal 513. Terminal 513 is provided with a recess 514 for fastening an external current conductor. In order to increase the mechanical stability of the contact rail when the current conductors are fastened, the section 513 outside of the housing may be designed as a longitudinal profile having at least one profile bar 515.
The section 511 of the contact rail is provided, for example in the center of the contact area of the stack of components, with a bore 510 for accommodating a bolt 411 which serves to establish the position of the stack of components. For this purpose, a corresponding contact projection 41 on the semiconductor element 4 is provided with a recess 401 at a corresponding position.
Each semiconductor element 4 is disposed on a respective surface area provided on the contact rail section 511 for this purpose. These areas are preferably adapted to the respective surface sections 18 of the bottom plate 1. The semiconductor elements themselves are shown as so-called press packs. What is important to the invention is the use of mutually coinciding contactable semiconductor elements, i.e. elements which have a configuration of their connecting electrodes which is essentially identical at both ends. Together with the further feature of the present invention, i.e. a releasably arranged pressure contacting, this permits exchange of the semiconductor elements and furnishes the best quality units with the desired electrical polarization. Encapsulated elements with a disc-shaped housing are therefore of advantage.
A further advantageous form of construction is shown in FIG. 3, to be described later.
One contact disc 52 and a stamp-like upper connecting lead 53 are concentrically arranged on the upper current contact of each semiconductor element 4. Each connecting lead 53 includes a connecting plate 531 and a connecting shaft 532 which is provided with a blind threaded bore 533 and simultaneously forms a current terminal outside of the housing.
A pressure contactng system 6 is mounted on each connecting lead 53 via a body 64 of insulating material for providing electrical insulation against current conducting components. System 6 includes a pressure disc 63, spring elements 62 and a pressure plate 61 which is common to both stacks of components. In virtue of the required mechanical stability during the pressure contacting preferably a pressure plate 61 of steel is provided.
The pressure plate 61 is provided with bores 611 for passage through and fixing of screw elements for the pressure contacting system. The long portion 641 and the flange portion 642 of each body 64 of insulating material enclose, in a matching configuration, the associated connecting lead 53 to the extent that the connecting plate 531 extends into a recess 643 of the flange portion 642.
The structure of the pressure contact system 6 is known per se and is not by itself part of the invention.
According to the present invention, the semiconductor elements 4 and their contact components, i.e. their respective concentrically attached and axially extending upper connecting leads 53, are releasably contacted and fixed to the bottom plate 1 with the aid of the common pressure plate 61 and the screw elements 81 which are screwed into the threaded bores 11 of the bottom plate 1 and press the pressure plate 61 onto the spring bodies 62 with a concentrically uniform pressure. This can be seen from the arrangement, orientation and position of the threaded bore 11 for the center one of the illustrated screw elements 81.
The number and arrangement of the screw elements 81 around the circumference of each stack of components are determined by the fact that the pressure plate is to exert an approximately uniformly acting concentric pressure on each stack. This can already be realized by providing three connecting screws 81 for each stack of components, i.e. by providing each stack with three associated screw elements 81 which are mutually angularly offset essentially by 120°. Since a screw element attached in the area between two stacks of components spreads its effect to both stacks, it is possible to provide, in a structure involving two stacks, one screw element on the longitudinal axis of the housing between the stacks of components and two screw elements between each stack and the housing wall with an offset by the corresponding angle as shown in broken lines in FIG. 2c. With such an arrangement, the contact rail 51 is provided with a corresponding opening 5111, also shown in broken lines in FIG. 2c, for passage of a screw element 81.
According to another preferred embodiment a four-screw connection is provided for each stack of components, with two screw elements 81 disposed on the center axis between the stacks of components, and two further screw elements provided in the area between each stack of components and the associated narrow side of the housing, as can be seen in FIG. 2c where bores 382 are provided for screws 81.
Reverting to FIG. 1, the stacks of components are accommodated in the housing frame 3 which is of insulating material, preferably plastic. The frame 3 is fastened directly to the bottom plate 1 and its circumference is essentially adapted to that of the bottom plate. For this purpose, the frame may be designed, for example, only as an annular body having, for example, a rectangular cross section, with one of its frontal, or end, faces adjacent the bottom plate 1 and its other frontal face adjacent a cover 9.
The housing frame 3 may be attached to the bottom plate, for example, by gluing. However, it may also be provided with sections having an increased end wall thickness and provided with stepped coaxial bores 31 and 311, or 32 and 321, respectively, for screwing screws 83 into threaded bores 12 of the bottom plate 1.
Furthermore, the housing frame 3 may be provided with an end plate 33 which is adjacent to the bottom plate 1. This end plate 33 has openings for passage of the stacks of components and the screw elements 81 of the pressure contact system 6 so that the housing frame 3 can also be releasably fastened to the bottom plate 1 together with the stacks of components.
The height of the housing is dimensioned so that with the cover 9 in place only the upper connecting lead 53 of each semiconductor element and the section 513 of the contact rail 51 outside of the housing are accessible.
If controllable semiconductor elements are provided, a conductor plate 7 is applied on the pressure plate 61 for fastening and bringing through the control lines. This conductor plate 7 is provided with openings 702 for attaching contact lugs 71 and recesses 703 for passage of the screw elements 81 and the connecting leads 53.
The housing frame 3 is closed by means of the cover 9 which is provided with openings 91 for passage of the connecting leads 53 and openings 92 for passage of the contact lugs 71. In the illustrated embodiments, it is further provided with recesses 94 for accommodating, in the interior of the housing, the upper ends of the screw elements 81. However, the semiconductor unit may also be dimensioned in such a manner that the screw elements 81 end below the cover 9. The cover further includes bores 93 for screws 92 to fasten the cover onto the pressure plate 61.
The semiconductor unit can thus always be disassembled due to the releasable screw connection of all components so that it is easy to replace components.
An opening remaining between the housing frame 3 and the cover 9 in the region of the contact rail section 513 is closed, for example, by a downward extension 95 of the cover 9.
The minimum mutual distance between the stacks of components in the housing is determined only by the requirement for sufficient voltage sparkover protection. In the embodiment according to FIG. 1, the contact rail 51 connects the lower current contacts of the semiconductor elements 4. If a separate contact rail is to be associated with each of the elements for independent operation of the semiconductor elements, the unit according to the invention can be assembled of two identical halves each corresponding to the right half of FIG. 1, and thus includes two separate contact rails. The free ends of the two contact rails may here be applied at the same level or at respectively different levels and may come out of the housing together on one side or separately at different sides of the housing.
The connecting plane for contact rail section 513, which is preferably disposed lower than the contacting face of the connecting leads 53, permits any desired electrical connection of the individual elements and/or of the unit with respect to circuitry and combination of components.
FIGS. 2a through 2c each show an example for a design of the housing frame for the fixed mounting of the stacks of components, each Figure showing one half of a unit. The frame 3 according to FIG. 2a has narrow sides of increased thickness, each narrow side having stepped bores 31 and 311 for separate fastening to the bottom plate 1, as this is also shown in FIG. 1.
In symmetry with the longitudinal axis of the housing, two slot-shaped recesses 34 are provided for accommodating the profile arms 515 of the contact rail 51 (see FIG. 1), for an arrangement in which the rail is provided with two such arms. The housing frame 3 which, for example, is essentially adapted to a rectangular bottom plate 1, has a rounded recess 37 at each corner to expose a respective bore 13 provided in the bottom plate 1 for fastening the unit to a cooling body or an instrument. The shaft 532 of the connecting lead 53 provided with the blind threaded bore 533 is enclosed by the long portion 641 of the body 64 of insulating material. Its flange member 642 has a cam-shaped projection 644. To prevent rotation of the connecting lead 53 when a current conductor is being attached by being screwed into bore 533, the recess 643 of the enclosing flange member 642 is designed, for example, in a polygonal shape and the connecting flange 531 of the connecting lead 53 is designed to match it and to engage therein. The cam-shaped projection 644 of the flange member 642 contacts a screw element 81 of the pressure contact system 6 to inhibit rotary movement of body 64.
Instead of positioning the stack of components by a screw element, this positioning can also be effected, for example, by means of positioning ribs 35 in the housing frame 3, as shown in FIG. 2b. These ribs can serve to fix the stacks of components and simultaneously to fix the upper connecting lead 53 against rotation, in that in virtue of the mutual fixing of the flange 53A and the projection 644 of the body 64 of insulating material said projection rests against such an adjusting rib, for example when the connecting components are released.
If, according to FIG. 2b, the adjusting ribs 35 are reinforced, e.g. in the form of columns 36 and attached to the corresponding points, they can each be provided with a bore 361 which simultaneously serves to guide a screw element 81 and thus to fix the housing frame 3 during the pressure contacting procedure. The bores 31 and 311 can then be omitted.
According to FIG. 2c, spacer members 38 which are disposed between the stacks and the housing walls are also suitable to fix the position of the stacks of components. These spacer members are essentially strip-shaped and have a matching recess 381 in the region of each semiconductor element 4, or of a stack of components each for its correct position, as well as correspondingly arranged bores 382 for the passage of the screw elements 81. Spacer members 38 can correspond in height of frame 3.
FIG. 3 shows a mutually coinciding contactable semiconductor element which has been formed in the housing frame 3 instead of a press pack. Such a semiconductor element shows a structure with identical contacting areas for its arrangement in an arbitrary electrical polarization.
To contact this element, a respective recess 39 is provided in the frame for each semiconductor element. This recess may be formed in a massive frame body or may be formed by rib-shaped projections between the frame walls, and is dimensioned for the insertion and guided arrangement of two contact plates 42 and 44 resting against opposite sides of the semiconductor body 43. The semiconductor body 43, whch is enclosed in the recess 39 between the contact plates 42 and 44, is tighly encapsulated, or sealed, along with its contact plates, by means of sealing rings 45 each disposed between a step-shaped edge zone of a respective contact plate and the wall of the recess inside the housing. A contact disc 52, connecting lead 53 and insulating body 64 are attached to this type of semiconductor element.
If the recesses 39 are provided in a massive housing body, the latter is preferably further provided with bores for the screw elements 81, if necessary with further bores for separately fastening the housing frame 3, and also with a recess for the engagement of each cam-shaped projection 644 to secure the connecting leads 53 against rotation.
The advantages of the present invention reside: in that it makes possible the best and most economical assembly without special treatment of components in a structure which meets all circuit requirements; in the assurance of predetermined parameters for the components and for the entire unit; in the possibility of monitoring the assembly without damage as desired; and in the fact that it is possible to arrange the semiconductor elements simply in any desired electrical polarization and to later change their polarization.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.
|
In a semiconductor unit composed of at least two semiconductor members eachrovided at each end with a respective current contact, a housing including a metallic base plate and a cover, elements for mounting the semiconductor members in electrically insulated and thermally conductive communication with the base plate, external connecting leads, and spring elements for establishing pressure contact between the leads and the current contacts, the connecting leads include a lower lead in the form of a contact rail contacting the current contact at that end of each member which is directed toward the base plate and interposed between the base plate and the members, and an upper lead for each member arranged concentrically with its respective member and contacting the current contact at that end of its associated member which is directed toward the cover, the contact rail includes a free end region which extends through an opening in the housing to provide an external connection in a selected connection plane, the cover is provided with an opening for each upper lead through which the upper leads extend to provide further external connections, and the unit further includes a structure securing each upper lead against rotation relative to the housing.
| 7
|
The present invention relates, in general, to a method and an apparatus for detecting the concentration or level of accumulation of microwave susceptible, particulate material on a filter medium and, more specifically, to a method and an apparatus for detecting soot accumulation on diesel engine exhaust filters.
BACKGROUND OF THE INVENTION
As is well known, a filter is placed in the exhaust system of diesel engines to remove soot from the exhaust gases of the engine. The filter must be changed or cleaned from time to time to ensure that soot accumulations do not adversely affect the operation of the engine. It is known to remove or incinerate the soot particles by subjecting the filter, in situ, to heat from a fuel burner or other heat generating device, or from suitable running of the engine. Incineration is to be performed when the accumulation has reached a level where further accumulation would adversely affect engine performance or that incineration would produce excessive temperatures and possibly damage the filter. There is a need, therefore, for a method and apparatus which monitors the level of soot accumulation and provides a signal when the accumulation reaches a predetermined level.
It is also known that soot accumulations exhibit dielectric properties. Accordingly, it is possible to monitor the level of soot accumulation on a diesel engine filter medium by detecting changes in the effective dielectric properties of the filter medium. By way of background, the complex permittivity of a material is comprised of two components: a real component called the dielectric constant and an imaginary component called the dielectric loss factor. Changes in either of these components can be detected using microwave interrogation methods.
One method of detecting changes in the effective dielectric constant involves exciting a microwave waveguide or transmission line, in which the filter is housed, with microwave energy at a fixed frequency and measuring the reflected power. For any RF system, a frequency can usually be found such that the electrical load, i.e. the filter medium, the diesel soot and the filter containment in this case, represents a matched impedance with respect to the power source. In other words, the equivalent electrical resistance, capacitance and/or inductance of the load are matched to the RF power source. When the load impedance is perfectly matched to the power source, all emitted RF power is absorbed by the load. If the impedance is not matched to the RF source, some of the RF power will be reflected from the load. The degree of load mismatch determines the amount of reflected power and hence reflected power can be used to measure the change in the effective dielectric constant.
U.S. Pat. No. 4,477,771 granted to the General Motors Corporation on Oct. 16, 1984 describes a method of detecting soot content in a particulate trap using this method. More specifically, the method is based on the principle of detecting changes in the effective dielectric constant only. The patent provides a filter housing which forms a closed, microwave resonance cavity in which a ceramic filter is placed. A single probe is positioned at one end of the cavity and behaves as both a transmitting and receiving antenna. A reflective screen is positioned at the opposite end of the cavity. All connecting exhaust pipe diameters are below the cutoff diameter of a circular waveguide needed to transmit the RF energy at the frequencies used in the device. The probe is connected to a microwave source through a directional coupler and an isolator. A detector is also connected to the probe through the directional coupler. In one mode of operation of the device, the microwave source is operated at the resonant frequency of the cavity when the filter is loaded with particulates to its maximum desired accumulation and the detector is operated to detect a null condition in the reflected signal which occurs at the resonant condition. Upon detecting such a condition, the detector generates an output signal operable to effect operation of a lamp or alarm. In a second embodiment, the reflective screen is eliminated and a second probe is positioned at the remote end of the cavity. One probe is connected to the power source and the other probe is connected to the detector.
It has been found that there are a number of technical and practical problems with this approach. First, the isolators and directional couplers are relatively complex devices needed to protect the RF source from the reflected power. From a practical point of view, the cost of these items would almost certainly preclude the device from being commercialized. Second, a power source of sufficient stability to allow long-term measurements at a single frequency without frequency drift would be prohibitively expensive. Third, and perhaps most importantly, the device tends to display poor sensitivity and is prone to large measurement errors due to the effect of temperature on the effective dielectric constant.
Another method involves exciting a microwave waveguide or transmission line with microwave energy at variable frequencies and measuring the reflected power. This is simply an extension of the method described in the General Motors patent. In accordance with this approach, the frequency is varied in order to minimize the reflected power. In effect, the frequency is varied in order to match the RF power source characteristics to the load impedance characteristics. Structurally, the device is the same as that described above except a variable frequency source is required. Frequency is used as the measurement parameter instead of reflected power. In addition the drawbacks discussed earlier, a variable frequency source and the required control logic would make this type of device prohibitively expensive.
SUMMARY OF THE INVENTION
The present invention seeks to provide a method and an apparatus which overcome the above described disadvantages by detecting changes in the effective dielectric loss factor as opposed to changes in the effective dielectric constant. In practice, this is achieved by exciting the filter chamber with microwave energy and measuring the transmission attenuation or loss due to changes in the filter effective dielectric loss factor caused by soot loading.
Thus, in accordance with one aspect of the present invention, there is provided a method of detecting the accumulation of particulate material collected on a filter medium formed of dielectric material and disposed in a chamber having the property of a microwave resonance waveguide or transmission line, the method comprising the steps of exciting the waveguide or transmission line with a microwave signal; and monitoring the transmission loss of the signal through the waveguide or transmission line to sense the effective dielectric loss factor thereof to provide an indication of the content of particulate material accumulated on the filter medium.
In accordance with one aspect of the present invention, there is provided an apparatus for detecting the accumulation of particulate material collected on a filter medium formed of dielectric material in a chamber having the property of a microwave waveguide transmission chamber, the apparatus comprising means for exciting the chamber with a microwave signal; and means for monitoring the transmission loss of the signal through the chamber to sense the effective dielectric loss factor thereof whereby to provide an indication of the content of particulate material accumulated on the filter medium.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings wherein:
FIG. 1 is a diagrammatic, cross-sectional view of a diesel exhaust particulate trap or filter adapted for microwave detection of the soot accumulation and a block diagram of an electrical circuit for carrying out the method of the present invention; and
FIG. 2 is a schematic of an electrical circuit in accordance with an embodiment of the present invention;
DESCRIPTION OF PREFERRED EMBODIMENT
FIG. 1 illustrates a steel, cylindrical filter housing 10 having a having frusto-conical steel end sections 12 and 14 adapted to the connected to engine exhaust pipes in a manner well known in the art. The housing is formed in such a manner that it behaves as a waveguide or microwave transmission line and includes a chamber 15 to receive a ceramic filter element 16 of suitable construction.
The construction of the filter and the housing do not form part of the present invention and, accordingly, neither component is described in detail herein. Suffice it to say that a large portion of the particulates which are carried into the housing by the exhaust gases are trapped and collected on the interior and exterior surfaces of the filter element. The collected particles build up to until, if left unattended, they eventually interfere with the performance of the engine. The soot particles affect both the dielectric constant and the dielectric loss factor properties of the filter. In practice, methods of detecting changes in the effective dielectric constant require measurement of parameters such as the power of the transmitted signal and the frequency of the signal as mentioned earlier which require expensive and precise equipment. Furthermore, the dielectric constant varies with temperature and, therefore, successful use of this method requires still further complexity. These difficulties can be overcome by the present invention as described below.
In accordance with the present invention, there is provided a method and an apparatus for detecting changes in the effective dielectric loss factor of the material in the chamber caused by changes in soot loading. In the preferred embodiment of the invention, this is achieved by detecting signal attenuation or loss of a microwave signal applied to the cavity. To that end, there is provided a first probe 20 which behaves as a transmitting antenna for RF power and a second probe 22 which serves as a receiving antenna. A modulator 24 generates an amplitude modulated tone signal which is fed to an RF source 26 which generates a carrier signal for the tone signal and applies the resulting signal to a splitter 28. Splitter 28 applies the signal to both transmitting probe 20 and a first detector 30. Detector 30 produces a reference output signal which is representative of the power of the signal prior to transmission. The use of an amplitude modulated signal allows the signal to be much more easily detected than by the method used in the aforementioned General Motors Corporation patent.
A second detector 32, electrically connected to second probe 22, produces an output signal representative of the power of the signal received by the second probe 22. The first and second detector output signals are applied to a comparator 34 which produces an output signal which is proportional to the difference in the signal strength of the transmitted and received signals. Accordingly, the comparator output signal is representative of the transmission loss through the filter medium which, in turn, is representative of the change in the effective dielectric loss factor caused by accumulation of soot on the filter. It will be seen therefore that when there is little or no accumulation in the filter, there will be only a small transmission loss in the signal strength. As the soot accumulation increases, the difference in signal strength between the transmitted and received signals changes, resulting eventually in an output signal from the comparator. The comparator can be designed to drive a variable output display or an indication when a predetermined level is reached, or both.
The power source is arranged to emit RF energy over a range of frequencies with the preferred frequency band being up to one octave, i.e. a 2 to 1 range, in frequency. An appropriate frequency band is 500 MHz to 1,000 MHz. There are three reasons for this. First, the average transmission loss through the filter over the selected frequency range results in better measurement sensitivity, i.e. attenuation per unit of soot present, and a more linear response as a function of RF signal attenuation than is possible at a single frequency. Second, it avoids problems associated with power source frequency drift with time. Third, the use of an averaging process demonstrably reduces the effects of temperature on transmission losses, i.e. the effects of temperature on soot and filter permittivity, which would otherwise require temperature compensation in single or narrow band frequency methods. The minimum frequency in the operating range is chosen to be above the cutoff frequency of a circular waveguide with the same diameter as the filter chamber. Frequencies below the cutoff frequency are greatly attenuated by chamber geometry producing poor measurement sensitivity for the determination of filter soot load.
With reference to FIG. 2, modulator 24 will be seen to be comprised of an operational amplifier 50 which, with resistors 52, 54 and 56 and capacitors 58, 60 and 62, forms a phase shift audio oscillator which provides a tone modulated signal along line 64. This signal is fed via capacitor 66 to the gate of a FET modulator transistor 68 which directly modulates the power supply to a frequency swept RF source 70, thereby imposing an AM audio tone on the RF signal output along line 72. Resistors 74 and 76 form the gate bias network for transistor 68.
Resistors 80, 82 and 84, capacitor 86 and operational amplifiers 88 and 90 form a sawtooth waveform sweep generator 92 which feeds a swept output signal to the frequency control port 94 of the RF source so as to cause the RF oscillator output to vary by up to one octave in frequency. The sweep rate is set by resistor 80 and capacitor 86.
The output of the RF source is applied to splitter 28 which is simply comprised of a resistor 100 in series with parallel connected resistors 102 and 104. The output of resistor 102 is fed to the transmit antenna or probe 20 while the output of resistor 104 is fed to the input of reference detector 30. For equal power division, the resistances of the three resistors are equal. The values of the resistances may be varied so that match is preserved with the system impedance but with most of the power passed to the soot filter.
Reference detector 30 and the signal detector 32 may be of identical construction as indicated by subcircuits 110 in FIG. 2. Each circuit 110 includes a capacitor 112 which provides DC isolation from a low-resistance source for a voltage-doubler signal detector 114 comprised of diodes 116 and 118. Resistors 120 and Capacitor 122 provide a level enhancing time constant for the detected modulation tone. Inductor 124 and capacitor 126 form a parallel tuned circuit at the tone frequency which curtails the passband and improves the signal to noise ratio. Capacitor 128 prevents inductor 124 from shorting resistor 120. Operational amplifier 130 amplifies the signal tone by about 30 dB. Diode 132 rectifies the amplified tone signal to DC, with capacitor 134 and resistor 136 setting the time constant and capacitor 138 and resistor 140 serving as a ripple filter. Each of the two detectors feed a respective input to the comparator.
Comparator 34 is formed with two sections generally designated by reference numerals 150 and 152. The reference detector output is fed directly to the negative input of the second section 152 and indirectly to the positive input of the first section 150 through a potentiometer 154. Similarly, the signal detector output is fed directly to the negative input of the first section 150 and indirectly to the positive input of the second section 152 through a potentiometer 156. The potentiometers serve to set the input levels from the signal and reference detectors to the two sections of the comparator. More specifically, in one section, potentiometer 154 sets its input below the output signal of the signal detector. As the signal level declines with increasing soot, a point is reached where the negative input to this section drops below the positive input and the output of the section is then pulled up by resistor 158. In the other section, potentiometer 156 is set so that the positive input is above the reference detector output only when the soot filter is clean. This serves as an optional check on the burn-clean cycle. With the signal above the reference detector, resistor 160 pulls up this output. The outputs are connected to indicator circuits not shown.
It will be understood that various modifications and alterations may be made to the present invention without departing from the spirit of the appended claims.
|
A method of detecting the accumulation of particulate material collected on a filter medium formed of dielectric material in a chamber having the property of a microwave waveguide or transmission line comprises the steps of exciting the chamber with a microwave signal and monitoring the transmission loss of the signal through the line to sense the effective dielectric loss factor and thereby to provide an indication of the concentration or level of particulate material accumulated on the filter medium.
| 5
|
BACKGROUND
1. Field of the Invention
The present invention relates to mechanisms for communicating information between semiconductor chips. More specifically, the present invention relates to a method and an apparatus for receiving and amplifying an input signal received from a capacitive sensor.
2. Related Art
Advances in semiconductor technology presently make it possible to integrate large-scale systems, including tens of millions of transistors, onto a single semiconductor chip. Integrating such large-scale systems onto a single semiconductor chip increases the speed at which such systems can operate, because signals between system components do not have to cross chip boundaries, and are not subject to lengthy chip-to-chip propagation delays. Moreover, integrating large-scale systems onto a single semiconductor chip significantly reduces production costs, because fewer semiconductor chips are required to perform a given computational task.
Unfortunately, integrating a large-scale system onto a single semiconductor chip greatly increases the data transfer rates required to communicate between semiconductor chips. Data is presently moved onto and off of a semiconductor chip through I/O pads located on the boundary of the semiconductor chip. Pin-grid array packaging technologies have increased the number of I/O pads available for this purpose. However, this increase has not kept pace with the exponential increase in the amount of circuitry that can be integrated onto a semiconductor chip.
Hence, as integration densities continue to increase, each I/O pin must satisfy I/O requirements for progressively larger amounts of on-chip circuitry. Furthermore, increasing integration densities allow higher clock on-chip speeds, and higher on-chip clock speeds mean that more clock cycles are required to move data from the interior of a semiconductor chip to the I/O pins on the border of the semiconductor chip.
Some researchers have begun to explore the possibility of using capacitive transmitters located on a first semiconductor chip to transmit signals to corresponding capacitive receivers located on the surface of a second semiconductor chip. This allows data to be transferred from directly from locations within the interior of the first semiconductor chip to locations within the interior of the second semiconductor chip without passing through I/O pins located on the chip boundaries. It also makes it possible to provide many more communication pathways between semiconductor chips because the signals do not have to be routed through a limited number of I/O pins.
However, the electrical signals received through a capacitive sensor are very weak, and must be greatly amplified in order to be used by circuitry within the semiconductor chip. This amplification process consumes a great amount of power because the amplification transistors must be kept very near their threshold levels in order to detect minute variations and input voltage. This power consumption is further multiplied if there exist large numbers of capacitive sensors.
Hence what is needed is a method and an apparatus for amplifying an input signal received from a capacitive sensor without consuming a large amount of power.
SUMMARY
One embodiment of the present invention provides a system for amplifying an input signal received from a capacitive sensor. The system includes an input for receiving an input signal from the capacitive sensor and an amplifier that amplifies the input signal to produce an output signal. This amplifier includes a pull-up circuit that pulls the output signal up to a high voltage when the input signal exceeds a threshold voltage. It also includes a pull-down circuit that pulls the output signal down to a low voltage when the input signal falls below the threshold voltage. After the output signal is pulled up to the high voltage, the pull-up circuit enters a refractory state in which the pull-up circuit uses a limited current, and the pull-down circuit enters a receptive state in which the pull-down circuit is sensitized to react to small changes in the input signal. After the output signal is pulled down to the low voltage, the pull-down circuit enters a refractory state in which the pull-down circuit uses a limited current, and the pull-up circuit enters a receptive state in which the pull-up circuit is sensitized to react to small changes in the input signal.
In one embodiment of the present invention, the system includes an output delay chain that produces feedback from the output signal. After the output signal is pulled up to the high voltage, this feedback causes the pull-up circuit to enter the refractory state and causes the pull-down circuit to enter the receptive state. After the output signal is pulled down to the low voltage, this feedback causes the pull-down circuit to enter the refractory state and causes the pull-up circuit to enter the receptive state.
In one embodiment of the present invention, the system includes a bi-stable circuit. This bi-stable circuit is configured to hold the output to the high voltage until the input signal falls below the threshold voltage. It is also configured to hold the output to the low voltage until the input signal rises above the threshold voltage.
In one embodiment of the present invention, the system includes a pull-up current mirror with the pull-up circuit that is configured to limit the current used by the pull-up circuit while in the refractory state.
In one embodiment of the present invention, the system includes a pull-down current mirror with the pull-down circuit that is configured to limit the current used by the pull-down circuit while in the refractory state.
In one embodiment of the present invention, when the pull-down circuit is in the receptive state and the input voltage drops below the threshold voltage, the pull-down circuit is configured to enter an active state in which the pull-down circuit draws sufficient current to rapidly switch the output signal to the low voltage.
In one embodiment of the present invention, when the pull-up circuit is in the receptive state and the input voltage rises above the threshold voltage, the pull-up circuit is configured to enter an active state in which the pull-up circuit draws sufficient current to rapidly switch the output signal to the high voltage.
In one embodiment of the present invention, the system includes a high resting voltage circuit that is configured to generate a high resting voltage for the input when the pull-up circuit is in the refractory state.
In one embodiment of the present invention, the system includes a low resting voltage circuit that is configured to generate a low resting voltage for the input when the pull-down circuit is in the refractory state.
In one embodiment of the present invention, the capacitive sensor is an I/O pad on a surface of a semiconductor chip.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1A illustrates how capacitive sensors are used to communicate between semiconductor chips in accordance with an embodiment of the present invention.
FIG. 1B illustrates circuitry that is used to drive signals to and from a capacitive interface in accordance with an embodiment of the present invention.
FIG. 2A illustrates a layout of capacitive transmitters on a semiconductor chip in accordance with an embodiment of the present invention.
FIG. 2B illustrates a layout of capacitive receivers on a semiconductor chip in accordance with an embodiment of the present invention.
FIG. 3 is a schematic diagram of an input buffer that amplifies a capacitive input signal in accordance with an embodiment of the present invention.
FIG. 4A illustrates circuitry that generates a resting potential for the circuitry illustrated in FIG. 3 in accordance with an embodiment of the present invention.
FIG. 4B illustrates circuitry that that acts as part of a current mirror for the circuitry illustrated in FIG. 3 in accordance with an embodiment of the present invention.
FIG. 4C illustrates circuitry that generates a resting potential for the circuitry illustrated in FIG. 3 in accordance with an embodiment of the present invention.
FIG. 4D illustrates circuitry that that acts as part of a current mirror for the circuitry illustrated in FIG. 3 in accordance with an embodiment of the present invention.
Table 1 is a partial state table for pull-up and pull-down pores in accordance with an embodiment of the present invention.
Table 2 illustrates the operation of the circuitry illustrated in FIG. 3 in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
Capacitive Sensors
FIG. 1A illustrates how capacitive sensors are used to communicate between semiconductor chips 102 and 104 in accordance with an embodiment of the present invention. In FIG. 1A, semiconductor chip 102 includes a number of capacitive transmitter plates, including capacitive transmitter plate 106 , located on its lower surface. Semiconductor chips 102 is aligned over semiconductor chip 104 , which includes a number of corresponding capacitive receiver plates, including capacitive receiver plate 107 . Note that there exists either an air gap or a small layer of dielectric material between corresponding capacitive transmitter and capacitive receiver plates.
Also note that semiconductor chips 102 and 104 can generally include any type of semiconductor chips. For example, semiconductor chip 102 may contain a microprocessor, while semiconductor chip 104 contains random access memory to be used by the microprocessor. In another example, semiconductor chip 102 contains a microprocessor and semiconductor chip 104 includes a graphics coprocessor.
FIG. 1B illustrates circuitry that is used to drive signals to and from a capacitive interface in accordance with an embodiment of the present invention. In FIG. 1B, output 110 drives a signal onto capacitive transmitter plate 106 . This causes a small voltage change on capacitive receiver plate 107 . This voltage change is amplified by input buffer 112 to produce an amplified signal that can be used by circuitry within semiconductor chip 104 .
Layout
FIG. 2A illustrates the layout of capacitive transmitters on a semiconductor chip in accordance with an embodiment of the present invention. In this embodiment, a number of capacitive transmitter plates are arranged in a grid pattern on the surface of semiconductor chip 102 . These capacitive transmitter plates have an exemplary size of 4 λ by 4 λ and an exemplary spacing of 40 λ by 4 λ.
FIG. 2B illustrates the layout of capacitive receivers on a semiconductor chip in accordance with an embodiment of the present invention. In this embodiment, the capacitive receiver plates are arranged in a grid pattern on the surface of semiconductor chip 104 . They also have exemplary size of 4 λ by 4 λ and an exemplary spacing of 40 λ by 40 λ. Furthermore, each capacitive receiver plate, such as capacitive receiver plate 107 , is surrounded by circuitry to implement an input buffer 112 . This circuitry is described in more detail below with reference to FIG. 3 .
Input Buffer
FIG. 3 is a schematic diagram of an input buffer 112 that amplifies a capacitive input signal in accordance with an embodiment of the present invention. Note that the circuit illustrated in FIG. 3 includes a number features seen in neurons and axons. First is a refractory period, during which a portion of the circuit is prevented from reacting to input changes. Second, it uses small charge pump currents to create resting potentials while waiting for the next input transition. These small charge pump currents dissipate little power. Third, it uses a receptive period, during which a portion of the circuit is sensitized to react to small input changes. The sensitization during the receptive period allows the circuit to transition quickly for the small input voltages expected for a capacitively-coupled input. This sensitization prevents the small charge pump currents from slowing the transition speed.
The circuit illustrated in FIG. 3 is divided into a pull-up pore (circuit) 302 , a pull-down pore (circuit) 304 , and an output delay chain 306 .
When the input node “In” is high, the circuit is in the high state. In the high state, the circuit waits for a falling input transition on the input node “In”, the pull-down pore 304 is refractive and the pull-up pore 302 is receptive. A falling input transition activates pull-up pore 302 . Pull-up pore 302 drives an internal “S” node high and through positive feedback drives the In node low. Later, the output delay chain 306 sets pull-up pore 302 to be refractory, and pull-down pore 304 to be receptive. This leaves the input buffer in the low state, waiting for the next rising transition.
When the input node “In” is low, the circuit is in the low state. In the low state, the circuit waits for a rising input transition on the “In” node, the pull-up pore 302 is refractive and the pull-down pore 304 is receptive. A rising input transition activates pull-down pore 304 . Pull-down pore 304 drives internal “S” node low and through positive feedback drives the In node high. Later, output delay chain 306 sets pull-down pore 304 to be refractory, and pull-up pore 302 to be receptive. This leaves the input buffer in the high state, waiting for the next falling transition.
The high and low resting potentials for the “In” node are set to cause pull-up pore 302 and pull-down pore 304 to output currents of I P1 and I N1 respectively, during their receptive periods. When refractory, pull-up pore 302 and pull-down pore 304 source and sink currents of I P2 and I N2 , respectively. The ratio of I P1 to I N2 and the ratio of I N1 to I P2 determine the input sensitivity. When the In node transitions due to a capacitively-coupled input, the receptive current increases, whereas the refractory current holds constant. Together, the refractory and receptive currents can be decreased to lower power consumption.
Referring to FIG. 3, pull-up pore 302 includes transistors P 1 to P 11 , pull-down pore 304 includes transistors N 1 to N 11 , and output delay chain 306 includes inverters V 1 and V 2 . Note that synapse capacitor, C, does not have to be a part of the circuit.
The input buffer illustrated in FIG. 3 can be used in an application where the output node D from the proceeding driver circuit is capacitively coupled by a capacitance C to the input node In.
During falling transitions, pull-up pore 302 pulls up node S, whereas during rising transitions, pull-down pore 304 pulls down node S. Note that they are referred to as “pores” because they have a receptive state during which a depolarizing transition on the In node causes the pore to rapidly “open,” pushing or pulling a large current onto or off of node S.
Vcsp 1 and Vcsn 1 are the high and low resting voltages for the input node, In. Vcsp 1 is chosen to make transistors P 1 and P 2 act as a current source, sourcing I P1 , when signal T is low. Vcsn 1 is chosen to make transistors N 1 and N 2 act as a current sink, sinking I N1 , when signal T is high.
TABLE 1
Pull-down pore (Block N)
Pull-up pore (Block P)
Node voltages
Current sunk
Current sourced
In
S
T
from S node
State
onto S node
State
Vcsn1
˜Vdd
Vdd
I N1
receptive
I P2
refractory
Vscn1 +
˜Vdd
Vdd
large current
activated
I P2
refractory
ΔV
Vcsp1
˜Gnd
Gnd
I N2
refractory
I P1
receptive
Vcsp1 −
˜Gnd
Gnd
I N2
refractory
large current
activated
ΔV
Vcsp 2 is a voltage that makes transistors P 3 and P 4 source a current I P2 . Vcsn 2 is a voltage that makes transistors N 3 and N 4 sink a current I N2 .
Table 1 shows four of the state combinations for the pull-up pore 302 and pull-down pore 304 . Pores 302 and 304 individually can be in the refractory, receptive, or activated states. In the refractory state pores 302 and 304 output a current of I N2 or I P2 that holds node S low or high (˜Gnd or ˜Vdd), respectively. In the receptive state pores 302 and 304 output a small current onto the S node (I N1 or I P1 ). The refractory currents are set to be larger than the receptive currents.
The +/−ΔV refers to the capacitively-coupled input voltage. Depending on the transition amplitude on node D, and the ratio of capacitance C to the parasitic capacitance on node In, ΔV will have different amplitudes. When ΔV sufficiently depolarizes the In node, the receptive pore activates and causes the input buffer to flip state.
The circuit achieves low power because the receptive (I N1 and I P1 ) and refractory currents (I N2 and I P2 ) can be set as low as desired. The ΔV amplitude that exceeds the depolarizing threshold and causes a transition is set by the ratio of the receptive to refractory current. The refractory current needs to be larger in order maintain positive feedback and thus hold the resting state. Increasing the ratio of refractory to receptive currents increases the depolarizing threshold, but decreases transition speed.
The circuit illustrated in FIG. 3 achieves high speed because when the In node depolarizes, one pore is activated, whereas the refractory pore remains refractory. The activated pore outputs a very large current. However, the pore in the refractory state outputs only the small I N2 or I P2 current. Thus, node S transitions similarly in speed to a domino logic node because there is only a constant opposing current during a transition.
Table 2 explains the operation of the circuit over a full cycle, resulting in two transitions of the output node. The sequence of events that occur during a transition are broken up into a series of steps presented over a number of Table rows.
The State column describes the overall state of the circuit. The circuit can be stable in either a high or low state, or can be transitioning between high and low. Table 2 steps through the events that occur during a transition. The columns for nodes D, In, S, Out, and T show the voltages on the nodes, whereas the columns for the transistors (N 1 to N 11 and P 1 to P 11 ) and inverters (V 1 and V 2 ) list the driving states of the transistors and inverters. Empty table cells indicate that the voltage or driving state is the same as the first non-empty cell above it in the table.
TABLE 2
State
D
In
S
Out
T
N11
P11
N1
N2
N3, N4
P1
P2
P3, P4
V1
V2
Stable Low
1
Gnd
Vcsn1
near Vdd
Gnd
Vdd
on
off
CS I N1
on
inactive
on
off
CS I P2
Transition
(Low to
High)
2
Vdd
Vcsn1 +
ΔV
3
weakly on
weakly on
4
near Gnd
5
off
on
LH
6
Vcsp1
Vdd
7
on
off
HL
8
Gnd
9
off
CS I N2
CS I P1
on
inactive
Stable High
10
Vdd
Vscp1
near Gnd
Vdd
Gnd
off
on
on
off
CS I N2
CS I P1
on
inactive
Transition
(High to
Low)
11
Gnd
Vscp1 −
ΔV
12
weakly on
weakly on
13
near Vdd
14
on
off
HL
15
Vscn1
Gnd
16
off
on
LH
17
Vdd
18
CS I N1
on
inactive
off
CS I P2
Stable Low
1
Gnd
Vscn1
near Vdd
Gnd
Vdd
on
off
CS I N1
on
inactive
on
off
CS I P2
Table 2, “CS” means that the transistors act together as a current sink (for nmos transistors) or source (for pmos transistors), of the indicated current I N1 , I N2 , I P1 , or I P2 . “Weakly on” means that the voltage on “In” makes the transistor (N 1 or P 1 ) on, but not strongly. For instance in a 3.3 Volt digital process, voltages on “In” that are within the middle third of the power supply range (˜1.1 to 2.2 Volts) could be considered to turn both the N 1 and P 1 transistors weakly on. “LH” means that the inverter (V 1 or V 2 ) is transitioning from a low to high output voltage. “HL” means that the inverter (V 1 or V 2 ) is transitioning from a high to low output voltage.
The Transition steps are broken up so that on a given row of the table either new node voltages, or new transistor and inverter driving states are introduced. It should be understood that the circuit does not strictly operate in this step to step fashion. For instance, transistors P 1 and N 1 regeneratively feedback to their inputs using transistors P 11 and N 11 . Hence, transitions on the In and S nodes occur with a degree of simultaneity. However, the step sequence description in the table is useful for illustrating the basic operation of the circuit.
Transistor P 4 and N 4 in the refractory current sources are always held on. They are there to mimic the “on” switches P 2 and N 2 in the receptive current sources. This allows a more precise ratio of the refractory to receptive current to be achieved.
FIGS. 4A-4D show the generation circuits for the Vcsp 1 , Vcsp 2 , Vcsn 1 , and Vcsn 2 signals. Note that Vcsp 1 and Vcsp 2 could be equal if the transistor sizes P 3 and P 4 were sized larger than transistor sizes P 1 and P 2 as needed to achieve the desired ratio of refractory to receptive currents. Likewise, that Vcsn 1 and Vcsn 2 could be equal if the transistor sizes N 3 and N 4 were sized larger than transistor sizes N 1 and N 2 as needed to achieve the desired ratio of refractory to receptive currents. The factors of M, K, R, and S indicate that the generation circuits can be scaled relative to the input buffer to provide the signals with a stronger drive strength.
Design Variations
A number of variations of the circuit illustrated in FIG. 3 are possible. For example, the ratio of the I P2 refractory current to the I P1 receptive current can be set by one or both of the following methods. In a first method, the ratio of transistors P 3 and P 4 to P 1 and P 2 can be changed. Larger P 3 and P 4 transistors increase the refractory current, whereas larger P 1 and P 2 transistors increase the receptive current. In a second method, Vcsp 1 can be modified relative to Vcsp 2 . Lowering Vcsp 2 relative to Vcsp 1 increases the refractory current to receptive current ratio.
Similarly, the ratio of the I N2 refractory current to the I N1 receptive currents can be set by one or both of the following methods. In a first method, the ratio of transistors N 3 and N 4 to N 1 and N 2 can be changed. Larger N 3 and N 4 transistors increase the refractory current, whereas larger N 1 and N 2 transistors increase the receptive current. In a second method, Vcsn 1 can be modified relative to Vcsn 2 . Raising Vcsn 2 relative to Vcsn 1 increases the refractory current to receptive current ratio.
The two refractory to receptive current ratios (I P2 :I N1 and I N2 :I P1 ) can be different. This makes rising and falling transitions have different speeds.
Transistors P 11 and N 11 can be weakened (by reducing the transistor width or increasing the transistor length). Weakened transistors allow a slow input edge to be recognized because P 11 and N 11 will not drive the In node as strongly. However, weakened P 11 and N 11 transistors will also slow down the buffer's forward delay and recovery times, and will increase noise sensitivity.
The output delay chain (V 1 and V 2 ) can be changed. For instance V 1 could include two or more inverters in order to provide for more amplification to the output node. V 2 could include two or more inverters to provide additional delay before switching the T node. This provides additional time before the pull-up or pull-down pore is switched into the refractory state. The only condition is that the sum of the number of inverters in V 1 and V 2 must be even and greater than or equal to two.
Transistors P 4 and N 4 could be omitted if desired to reduce the total number of transistors in the circuit to save area. However, this would adversely affect the ability to set an exact ratio between the refractory and receptive currents.
Multiple inputs (D 1 , D 2 , . . . DN) connected by multiple capacitors (C 1 , C 2 , . . . CN) could be connected to node In. This would allow for the input buffer to also perform a temporal-based logic function on the D 1 to DN signals. If a sufficient number of D* signals transitioned in the same direction in a short period of time, then the input buffer would transition. This implements the sum of products function and a threshold operation.
The foregoing descriptions of embodiments of the present invention have been presented for purposes of illustration and description only. They are not intended to be exhaustive or to limit the present invention to the forms disclosed. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art. Additionally, the above disclosure is not intended to limit the present invention. The scope of the present invention is defined by the appended claims.
|
One embodiment of the present invention provides a system for amplifying an input signal received from a capacitive sensor. The system includes an input for receiving an input signal from the capacitive sensor and an amplifier that amplifies the input signal to produce an output signal. This amplifier includes a pull-up circuit that pulls the output signal up to a high voltage when the input signal exceeds a threshold voltage. It also includes a pull-down circuit that pulls the output signal down to a low voltage when the input signal falls below the threshold voltage. After the output signal is pulled up to the high voltage, the pull-up circuit enters a refractory state in which the pull-up circuit uses a limited current, and the pull-down circuit enters a receptive state in which the pull-down circuit is sensitized to react to small changes in the input signal. After the output signal is pulled down to the low voltage, the pull-down circuit enters a refractory state in which the pull-down circuit uses a limited current, and the pull-up circuit enters a receptive state in which the pull-up circuit is sensitized to react to small changes in the input signal.
| 7
|
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. Ser. No. 07/723,899 filed Jul. 1, 1991, now abandoned, which application Ser. No. 07/723,899 is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
The present invention relates to anesthesia, especially local anesthetics. More particularly, this invention relates to a method for controlling the duration of local anesthesia, and to a reagent system or kit for inducing and limiting or reversing local anesthesia produced.
Anesthetic agents are pharmacologically active agents that block nerve conduction when applied in therapeutically effective amounts. They can be used for local application, namely to a localized area, for example, by application to the skin or other dermal membrane, or for systemic application, e.g., by the intraperitoneal or intravenous routes of administration.
The anesthetic agent may be applied locally by injection, ointments, jellies, topical solutions and suspensions or other forms known for topical administration.
Local anesthetics generally are esters or amides of benzoic acid, typically administered as an acid addition salt in dosages known to those skilled in the art.
For example, as applied to the region of the mouth and adjacent areas of humans, anesthesia involves injection of anesthetic agents including roughly 2 to 3% lidocaine, 2 to 3% mepivacaine, 0.5% marcaine or 3 to 4% prilocaine, usually administered in aqueous solution in the form of a water-soluble acid-addition salt, typically the hydrochloride salt. Also, as practiced, vasoconstricting agents such as epinephrine, phenylphrine or levonordenphedrine may be administered concomitantly or separately with the local anesthetic agent in order to prolong the duration of the local anesthesia, reportedly by constriction of blood vessels, resulting in prolongation of the contact of the anesthetic with the nerve.
Aqueous Lidocaine hydrochloride in sodium bicarbonate has been used in spinal and epidural anesthesia to speed up the onset of anesthesia to reduce the burning upon injection and to lengthen the duration of action.
In some areas, especially in the mouth, the local anesthesia may last longer than needed. This is debilitating and restrictive to the patient's normal activity. The administration of a local anesthetic at relatively low pH, typically in the range of about pH 2 to about pH 5.5, has been reported to retard the duration of anesthetic action.
SUMMARY OF THE INVENTION
The inventor has discovered that the duration of the local anesthesia can be reversed or limited by the subsequent administration of an inorganic or organic salt reversing agent in a fluid which is preferably an aqueous solution having a pH equal to or greater than about pH 7, preferably a pH of about 7 to about 8.5. The upper limit of the pH is not critical except that, in practice, the upper limit of the pH is affected by the nature of the salt, and any buffer, the concentration of base used to adjust the pH.
This invention thus provides a method of limiting duration of local anesthesia or reversing the anesthesia. This method is comprised of the steps of (a) administering an effective amount of an anesthetic agent to a local area of the subject; and (b) subsequently administering an effective amount of a reversing agent which is an inorganic or organic salt in a fluid having a pH equal to or greater than pH 7. The reversing agent limits the duration of anesthesia activity. Optionally, the reversing agent can be in buffered solution or the anesthetic agent can be applied in conjunction with a vasoconstrictor to prolong the anesthetic action, or both.
This invention also includes a reagent system for use in the method which comprises (a) first container containing an anesthetic agent and (b) a second container containing a reversing agent which is an inorganic or organic salt in a fluid having a pH of at least about 7, and preferably about pH 7 to 8.5.
The reversing agent is preferably administered in the form of a pharmaceutically acceptable pyrogen free mixture, preferably an aqueous solution in a concentration of about 4.0% to about 8.4% by weight, though concentrations substantially greater than 8.4% and substantially less than 4.0% will also reverse the duration of the local anesthesia. The amount of reversing agent administered, as known in the art, depends on the size and body weight of the patient, the area to be anesthetized, the route of administration and the concentration of anesthetic agent, but is typically approximately 1.8 to 6.0 cubic centimeters of a mixture of the foregoing concentration.
The inorganic or organic salt of the reversing agent is preferably the salt of a weak acid, and strong base, or weak base.
The method and reagent can optionally be used in conjunction with a vasoconstrictor to prolong the duration of the action.
In a preferred embodiment of this invention, the anesthetic agent is lidocaine or mepivacaine, preferably in the form of the hydrochloride acid-addition salt, and the reversing agent is sodium bicarbonate, calcium gluconate or calcium chloride.
DETAILED DESCRIPTION OF THE INVENTION
The method of this invention relates to limiting the duration of local anesthesia or reversing anesthesia in a subject, comprising the steps of
(a) administering an effective amount of an anesthetic agent to a local area of a subject to produce anesthesia; and
(b) subsequently applying an effective amount of a non-toxic inorganic or organic salt reversing agent in a fluid having a pH equal to or greater than about pH 7, in order to limit the duration of anesthesia or reverse anesthesia.
The term "subject" according to the present invention is intended to include all warm-blooded mammals, preferably humans.
The term "anesthetic agent" used here refers to non-toxic and for injection, pyrogen free substance known to be suitable for inducing local anesthesia in warm-blooded mammals and includes a large class of known compounds which generally are esters or amides of benzylic acid derivatives, typically administered for convenience in the form of an aqueous solution of an acid addition salt. Anesthetics useful for this purpose include lidocaine, bupivicaine, chloroprocaine, editocaine, mepivacaine, prilocaine, procaine and tetracaine, all of which are commercially supplied for use as local anesthetics in the form of the hydrochloride acid-addition salt typically in aqueous solution. Other useful amines or amides suitable as local anesthetics include benoxinate, proparacaine, dibucaine, diclonine and pramoxine. Less suitable are local anesthetics of low solubility including benzocaine and small quantities of the toxins tetrodotoxin and saxitoxin. Also less suitable because of its addictive properties is cocaine.
The term "local anesthesia" is commonly understood by the skilled artisan to mean an anesthesia having an effect only to one spot or part and not general.
The term "effective amount" as applied to the anesthetic agent means amounts known to be effective for topical application. Such amounts depend on the agent to be used, the location of administration and the form of the anesthetic. In general, lidocaine is commercially available as the hydrochloride and is used in preparations in about 0.5 to about 20% by weight, volume, some with and some without epinephrine for infiltration, about 1 to 2% for block and about 5% for topical mucosal anesthesia. Bupivicaine is used commercially as the hydrochloride in solutions from about 0.25 to about 0.75%; chloroprocaine is used as the hydrochloride in solutions of about 1 to 3%. Ediocaine is used as the hydrochloride in solutions of about 1 to 2%. Mepivicaine is used in solutions of about from 1 to 3% with or without levonordenphedrine as a vasoconstrictor. Prilocaine is used as the hydrochloride in solution at about 4% with or without epinephrine as a vasoconstrictor. Procaine is used as the hydrochloride in solutions of about 0.25 to 0.5% for infiltration, 0.5% to 2% for peripheral nerve block and 10% for spinal anesthesia. Tetracaine is used in solutions as the hydrochloride of about 5% as an ointment and about 2% for application to the mucous membranes or throat. Tetracaine for injection is available in solutions or ampules containing the dry salt, as well as ointments of 5% and creams of 1%.
The term "non-toxic" used here means that the agent should not cause any permanent damage to the nerve structure. In addition, its systemic toxicity should be low because the anesthetic agent is eventually absorbed from the site of application. In addition, anesthetic agent is preferably not irritating to the tissue to which it is applied.
The term "pyrogen free" when applied to the agents used for injection means that the mixture in question does not contain substances known to cause a pyrogenic response. Pyrogens can be removed from any mixtures by methods known in the art.
Typically, the local anesthetic is administered in a solution from about 0.5 to 5% and in other mixtures of up to 20% or 30% or more by weight/volume. The amount administered for any local anesthesia depends on the route or locale for administration. For application to the oral cavity, the amount used generally is no more than 6 cubic centimeters ("cc") of a 2% solution. Preferably the salt is administered in a concentration of from about 2% to 10% in an amount of about 0.5 to 6 cc.
The anesthesia is applied locally in known ways including surface anesthesia, infiltration, field block anesthesia, nerve block anesthesia, intravenous regional anesthesia, spinal anesthesia and epidural anesthesia. Surface anesthesia involves topical application to the mucous membranes such as those found in the nose, mouth, throat, tracheo- bronchial tree, esophagus and the genitourinary tract. Infiltration anesthesia consists of an injection of the anesthetic directly into the tissue to be incised or mechanically stimulated. This anesthesia can be superficial so as to include only the skin or include deeper structures including intraabdominal organs when they are infiltrated. Infiltration or other regional anesthetic techniques permit good anesthesia without disruption of normal body functions. Field block anesthesia is produced by subcutaneous injection of the local anesthetic to interrupt nerve transmission proximal to the site to be anesthetized. Nerve block anesthesia involves injection of the anesthetic into or about individual or peripheral nerves or nerve plexus to produce greater areas of anesthesia than the previous methods. Intravenous regional anesthesia involves injection of the solution into a vein of an extremity previously exsanguinated and kept exsanguinated. Spinal anesthesia involves injection of the anesthetic into the lumbar subarachnoid space. Epidural anesthesia involves injection of the anesthetic into the epidural space.
After local anesthesia has been accomplished, the anesthesia can then be reversed or limited by the administration of an effective amount of a non-toxic, preferably pyrogen free inorganic or organic salt reversing agent in a fluid having a pH equal to or greater than about pH 7, preferably a pH of about 7 to about 9 and more preferably a pH of about 7 to 8.5. The upper limit of the pH of the reversing agent is not critical. However, in practice, the upper limit of pH is determined by the nature of the salt, any buffer or base present, and the concentration of the foregoing. Additionally, the sensitivity of the skin to basic substances is such that a pH of not more than 10 and preferably not more than 9 is preferred.
The term "inorganic or organic salt" when used with reference to the reversing agent refers to a non-toxic, preferably water soluble, salt in a preferably pyrogen free mixture which is capable of being adjusted to a pH of at least 7 and preferably at least about a pH of 7.0 and more preferably a pH of 8. The salt is preferably an alkali or alkaline earth metal salt of an inorganic and organic acid. In order to achieve the desired pH, the salt should either be the salt of a weak acid and strong base, or of a weak acid and a weak base.
Typical cations of the salt are sodium, potassium, calcium and magnesium. Typical anions are monovalent inorganic anions such as fluoride, bromide and chloride; multivalent organic anions such as carbonate, hydrogen carbonate; and multivalent inorganic anions such as sulfate and phosphate. Non-toxic inorganic anions of organic acids include anions of mono-like and dibasic organic acids such as the acetate, gluconate and monoordicarboxylic acids.
Preferred reversing agents are sodium bicarbonate, calcium gluconate and calcium chloride.
In order to maintain the salt at the desired pH, the salt can be administered in a buffer which will maintain the mixture containing the salt at a pH of at least 7 and preferably a pH of at least 7.8 and more preferably a pH from about 7 to 8.5. Typical buffers are those known in the art and include inorganic and organic buffers including phosphate, citrate, bicarbonate and the like.
As used herein, reference to "affecting" the duration of local anesthesia and "to reverse or limit" the duration of anesthesia means that the administration of the inorganic or organic salt serves to significantly reduce the duration of anesthesia over that which would occur in the absence of the reversing agent. This affecting of the duration of anesthesia may involve merely shortening the duration of action or totally reversing the anesthesia upon the administration. The amount of reversing agent administered determines whether the anesthesia is limited or totally reversed. The amount of reversing agent necessary is dependent on whether limitation or reversal is desired, the half life of the anesthetic agent by the route of administration used and the timing of the administration of the reversing agent. Appropriate dosages in amounts will be apparent to one skilled in the art or can be determined by simple routine experimentation.
The term "effective amount" when applied to the reversing agent refers to an amount necessary to reverse or limit the anesthesia that has been induced. As indicated, this amount can be determined by a person skilled in the art and typically is a molar amount or concentration at least equal to or less than the molar amount of the anesthetic agent that has been injected or the remaining unmetabolized anesthetic agent in the area of application.
As is known in the art, the anesthetic agent can be administered concomitantly with a vasoconstrictor to prolong the duration of action. The term "vasoconstrictor" used here means an agent capable of causing constriction of blood vessels including various sympathomimetic drugs such as epinephrine, norepinephrine, levonordenphedrine and dopamine.
Typically, epinephrine is administered in a dilution of 1:100,000 mixed with a solution of lidocaine and supplied in 1.8 cc capsules.
In accordance with the method of this invention, the reversing salt is preferably administered in a non-toxic, pyrogen free fluid mixture.
The term "fluid" used here means any vehicle suitable for topical administration including solutions in suspensions for injections, ointments, jellies, topical solutions in suspensions and other forms known for topical administration. To the extent the anesthetic agent is administered by injection, then the reversing solution to achieve its optimal effectiveness should also be administered by injection. Where injections are used, the fluid of the reversing solution is conveniently water. In any event, the reversing agent is administered by the same means and route as the anesthesia.
Most conveniently, the salt is present, depending upon the solubility of the salt, in an amount of approximately 1 molar in aqueous solution. In the case of sodium bicarbonate, a 1 molar, or meq/ml (84 mgs/ml) solution has a pH of about 7.8. Such a solution is conveniently contained in an individual dosage unit of a size of approximately 1.8 cc where application to the oral cavity is concerned.
As indicated above, the pH of the reversing mixture is equal to or greater than about 7 and more preferably about 7 to 8.5 or 9.0 Use of a reversing salt having a pH of greater than 9 tends to be less effective and thus is not as desirable as use of a reversing solution at a pH of about 7 to 8.9. The reversing mixture can be a simple mixture of a vehicle and the salt. Alternatively, the reversing solution can contain a buffer to maintain the pH at the desired level.
The amount of the solution used, particularly with respect to reversing of anesthesia in the oral cavity, is about 0.6 to 6.6 cc when the reversing agent is present in a concentration of 4.0 to 8.4% by weight.
In one embodiment of the present invention, the reversing agent is administered at a concentration of 2% to 10% by weight/volume in an amount of about 0.5 to 6 cc. In a preferred embodiment, the reversing agent is sodium bicarbonate in a solution of about 8% by weight and having a pH of about 7 to 9.
Another feature of this invention is a reagent system for use in inducing and reversing the local anesthesia. Such system conveniently includes a container such as a carpule which contains the local anesthetic agent, a container or carpule of sodium bicarbonate for reversing the anesthesia, and optionally a container or carpule containing other substances to be used in conjunction therewith, for example, calcium ion for relieving any conduction block produced by the anesthetic. Instead of carpules, the system may alternatively include other known containers suitable for delivering their contents to the site of anesthesia.
In one example, the reagent system of the invention is comprised of carpule containing a the local anesthetic and a vasoconstrictor and a carpule containing sodium bicarbonate solution for reversing the local anesthesia.
The solutions for use in this invention can contain additional additives known for use in sterile pharmaceutical solutions and suspensions including, but not limited, to stabilizers, antimicrobial agents, suspending agents and other ingredients known to enhance the use and shelf life of the products of this invention.
Further objects and advantages of this invention will be apparent from the following examples. In the following examples, all references to anesthetic agents refer to the agent administered in the form of the hydrochloride salt, "meq" refers to milliequivalent, "ml" refers to milliliters, "mgs" refers to milligrams, percentages refers to percentages by volume in the case of two or more liquids, and percent by weight to percent by volume in the case of solids and liquids, "cc" refers to cubic centimeters. The following examples are given by way of illustration and should not be considered to limit the invention.
______________________________________METHODS OF SAMPLE EXPERIMENTSTO SUPPORT THE INVENTION______________________________________Initial injection and controls = anesthetizing agentsI lidocaine 2%II lidocaine 2% with 1:100,000 epinephrineIII mepivacaine 3% plainIV mepivacaine 2% with 1:20,000 levonordenphedrineSecond injection = potential reversal agents0.5 cc NaHCO3 8.4% sodium bicarbonate 1 meq/ml (84 mgs/ml sod. bicarb.)0.5 cc 0.9% NaCl - pH 5.5 (9 mg NaCl/ml)0.5 cc 0.9% NaCl + acid (dilute hydrochloric acid 1:500 2 mg/ml) (3 cc of 0.9% NaCl with 0.05 cc of HCl to pH 5.00)______________________________________
Experiment Design
Subjects received injections to right or left arms at several sites. The first injection, usually 0.5 cc-0.6 cc, was followed by a second injection of the same volume to the same site as the initial injection. The second injection was placed within 5 to 20 minutes of the first injection.
Pin prick tests were done every 5 minutes until sensation returned at all sites (usually by 6 hours). Tests were conducted double blind.
EXPERIMENT I______________________________________Initial Injection - 0.5 cc of 2% lidocainewith 1:100,000 epinephrine at all sitesControl = Solution DSecond Injection - SolutionsA. 0.5 cc of 0.9% NaCl + acid (dilute HCl 1:500 2 mg/ml)pH 5.0B. 0.5 cc of 8.4% NaHCO3 (1 meq/ml sodium bicarbonate)pH 7.8C. 0.5 cc of 0.9% NaCl solution pH 5.5D. Control - 0.5 cc solution of 2% lidocaine withepinephrine______________________________________Second Injection Time to positive pinresults prick______________________________________A. 0.9 NaCl + acid 5 hours 50 min.B. 8.4% NaHCO3 45 minutesC. 0.9 NaCl 5 hours 50 min.D. 2% lidocaine w/epinephrine 5 hours 50 min.______________________________________ Results: Solution B reversed the local anesthesia in 45 minutes, i.e., around 1/6 of the control time.
EXPERIMENT II______________________________________Initial Injection - 0.5 cc of 2% lidocaine with 1:100,000epinephrine at all sitesControl = Solution CSecond Injection - SolutionsA. 0.5 cc NaCl - 0.9 normal solution 0.5 cc pH 5.5B. 0.5 cc 8.4% sodium bicarbonate pH 7.8C. Control - 0.5 cc 2% lidocaine with 1:100,000 epinephrine pH 5.5______________________________________Second Injection - Time to positive pinresults prick______________________________________A. NaCl 3 hours 35 min.B. NaHCO3 1 hour 25 min.C. Control 2% lidocaine with 3 hours 35 min. 1:100,000 epinephrine______________________________________ Results: Solution B was positive after 1 hour 25 minutes or reversal achieved in less than half the control time.
EXPERIMENT III______________________________________Initial Injection - 0.5 cc lidocaine 2% plain withoutvasoconstrictor at all sitesControl = Solution CSecond Injection - SolutionsA. 0.5 cc NaCl - 0.9 normal solution pH 5.5B. 0.5 cc 8.4% NaHCO3 - pH 7.8C. 0.5 cc 2% lidocaine pH 5.0______________________________________Second Injection - Time to positive pinResults prick______________________________________A. NaCl 2 hours 5 min.B. NaHCO3 1 hourC. Lidocaine 2 hours 15 min.______________________________________ Results: Solution B was positive after 1 hour or reversal achieved in les than half the control time.
EXPERIMENT IV______________________________________Initial Injection - 0.5 cc of 2% mepivacaine with1:20,000 levonordenphedrine at all sites pH 4.5Control = Solution CSecond Injection - SolutionsA. 0.5 cc NaCl - 0.9 normal solution pH 5.5B. 0.5 cc NaHCO3 - 8.4% - 1 meq/ml - pH 7.5C. 0.5 cc 2% mepivacaine + 1:20,000 levonordenphedrine pH 4.5______________________________________Second Injection - Time to positive pinresults prick______________________________________A. NaCl 3 hours 20 min.B. NaHCO3 1 hour 55 min.C. Mepivacaine + levonorden- 3 hours 20 min. phedrine______________________________________ Results: Solution B was positive after 1 hour and 55 minutes resulting in a reversal of about roughly onehalf time than the control time.
EXPERIMENT V______________________________________Initial Injection - 0.5 cc 3% mepivacaine plain at allsites pH 4.5-5.0Control = Solution CSecond Injection - SolutionsA. 0.5 cc NaCl 0.9 normal solution pH 5.5B. 0.5 cc 8.4% NaHCO3 pH 7.8C. 0.5 cc 3% mepivacaine plain______________________________________Second Injection - Time to positiveresults pin prick______________________________________A. NaCl 2 hours 10 min.B. NaHCO3 1 hour 20 min.C. Mepivacaine 2 hours 40 min.______________________________________ Results: Solution B was positive after 1 hour 20 minutes or resulting in reversal in half the time of the control.
EXPERIMENT VI______________________________________Initial Injection - 0.6 cc of 2% lidocaine with 1:100,000epinephrine at all sitesControl = Solution ESecond Injection - SolutionsA. 0.6 cc Bacteriostatic H.sub.2 O pH 5.5B. 0.6 cc 4.0% NaHCO.sub.3 pH 7.5C. 0.6 cc 8.4% NaHCO.sub.3 pH 7.8D. 0.6 cc NaCl - 0.9 normal pH 5.0E. 0.6 cc 2% lidocaine with 1:100,000 epinephrine pH______________________________________ 4.5Second Injection - Time to positiveresults pin prick______________________________________A. H.sub.2 O 6 hours 59 min.B. 4.0% NaHCO.sub.3 5 hours 46 min.C. 8.4% NaHCO.sub.3 5 hours 10 min.D. 0.9 N aqueous NaCl 4 hours 9 min.E. 2% lidocaine with 8 hours 53 min. 1:100,000 epinephrine______________________________________ Results: Solution C achieved a faster reversal than Solution B. Both Solution C and Solution B achieved reversal in less time than the control (Solution E)
EXPERIMENT VII______________________________________Initial Injection - 0.6 cc of 2% carbocaine with1:100,000 levonordenphedrine at all sites pH 4.5Control = Solution ESecond Injection - SolutionsA. 0.6 cc 4.0% NaHCO.sub.3 pH 7.5B. 0.6 cc 8.4% NaHCO.sub.3 pH 7.8C. 0.6 cc NaCl - 0.9 normal pH 5.0D. 0.6 cc Bacteriostatic H.sub.2 O pH 5.5E. 0.6 cc 2% carbocaine with 1:100,000 levonorden- phedrine 1:100,000 epinephrine levonor- denphedrine pH 4.5______________________________________Second Injection - Time to positiveresults pin prick______________________________________A. 4.0% NaHCO.sub.3 3 hours 46 min.B. 8.4% NaHCO.sub.3 1 hour 43 min.C. NaCl 6 hours 53 min.D. H.sub.2 O 8 hours 13 min.E. 2% lidocaine with 8 hours 10 min. 1:100,000 levonordenphedrine______________________________________ Results: Solution B achieved a faster reversal than solution A. Both Solution B and Solution A achieved reversal in about one third to one hal less time than the control (Solution E).
EXPERIMENT VIII______________________________________Initial Injection - 0.6 cc of 3.0% carbocaine plainwithout vasoconstrictor at all sites pH 4.5-5.0Control - Solution ESecond Injection - SolutionsA. 0.6 cc H.sub.2 O pH 5.5B. 0.6 cc 4.0% NaHCO.sub.3 pH 7.5C. 0.6 cc 8.4% NaHCO.sub.3 pH 7.8D. 0.6 cc NaCl - 0.9 normal pH 5.0E. 0.6 cc 3.0% carbocaine______________________________________Second Injection - Time to positiveresults pin prick______________________________________A. H.sub.2 O 1 hour 7 min.B. 4.0% NaHCO.sub.3 33 min.C. 8.4% NaHCO.sub.3 32 min.D. NaCl 1 hour 30 min.E. 0.6 cc 3.0% carbocaine 1 hour 33 min.______________________________________ Results: Solution C achieved a slightly faster reversal than Solution B. Both Solution C and Solution B achieved reversal in less time than the control (Solution E).
EXPERIMENT IX______________________________________Initial Injection - 0.5 cc of 2% lidocaine with 1:100,000epinephrine at all sites.Control - Solution ESecond Injection - SolutionsA. 0.5 cc H.sub.2 O pH 5.5B. 0.5 cc water adjusted to pH 11.5 with 0.1 N sodium hydroxideC. 0.5 cc 8.4% aqueous NaHCO.sub.3 pH 7.8D. 0.5 cc H.sub.2 O adjusted to pH 12 with 0.1 N sodium hydroxideE. 0.5 cc 2% lidocaine with 1:100,000 epinephrine pH______________________________________ 5.0Second Injection - Time to positiveresults pin prick______________________________________A. H.sub.2 O 5 hours 13 minutesB. H.sub.2 O adjusted to pH 11.5 7 hours 22 minuteswith 0.1 N sodium hydroxideC. 8.4% NaHCO.sub.3 4 hours 36 minutesD. Sterile H.sub.2 O adjusted to pH 12 >7 hours 55 minuteswith 0.1 N sodium hydroxideE. 2% lidocaine with 5 hours 14 minutes1:100,000 epinephrine______________________________________ Results: Solution C achieved the fastest reversal. Solutions B and D achieved a reversal in greater time than the control solution (E).
EXPERIMENT X______________________________________Initial Injection - 0.5 cc of 2% carbocaine plain withoutvasoconstrictor at all sites pH 4.5-5.0.Control - Solution ESecond Injection - SolutionsA. 0.5 cc H.sub.2 O pH 5.5B. 0.5 cc water pH adjusted to 11.5 with 0.1 N sodium hydroxideC. 0.5 cc water adjusted to pH 12 with 0.1 N sodium hydroxideD. 0.5 cc 8.4% NaHCO.sub.3 pH 7.8E. 0.5 cc 2% carbocaine plain without vasoconstrictor at all sites pH 4.5-5.0______________________________________Second Injection - Time to positiveresults pin prick______________________________________A. H.sub.2 O 21 minutesB. 0.5 cc water adjusted to pH 11.5 21 minuteswith 0.1 N sodium hydroxideC. 0.5 cc water adjusted to ph 12 10 minuteswith 0.1 N sodium hydroxideD. 8.4% aqueous NaHCO.sub.3 20 minutesE. 2% carbocaine 1 hour 24 minutes______________________________________ Results: Solution C achieved the fastest reversal. Solutions A, B, and D achieved a faster reversal than the control solution E.
EXPERIMENT XI______________________________________Initial Injection - 2% carbocaine with 1:100,000levonordenphedrine at all sites.Control - Solution ESecond Injection - SolutionsA. 0.5 cc H.sub.2 O pH 5.5B. 0.5 cc water adjusted to pH 11.5 with 0.1 N sodium hydroxideC. 0.5 cc water adjusted to pH 12 with 0.1 N sodium hydroxideD. 0.5 cc 8.4% NaHCO.sub.3 ph 7.8E. 0.5 cc 2% carbocaine with 1:100,000 levonordenphedrine pH 4.5______________________________________Second Injection - Time to positiveresults pin prick______________________________________A. H.sub.2 O 6 hoursB. 0.5 cc water adjusted to pH 11.5 7 hours 49 minuteswith 0.1 N sodium hydroxideC. 0.5 cc water adjusted to pH 12 7 hours 49 minuteswith 0.1 N sodium hydroxideD. 8.4% NaHCO.sub.3 49 minutesE. 2% carbocaine with 7 hour 51 minutes1:100,000 levonordenphedrine______________________________________ Results: Solution D achieved the fastest reversal. Solution A achieved a faster reversal than control solution E.
CONCLUSION
The above experiments confirm the hypothesis of the invention. The tests have shown that 4.0% and 8.4% NaHCO3 solutions can reduce or reverse the local anesthetic working times. Furthermore, 8.4% NaHCO 3 solutions achieve a faster reversal of the local anesthetic than 4.0% NaHCO 3 solutions.
|
A method of controlling the duration of local anesthesia and a reagent system or kit for inducing and limiting the duration of local anesthesia is described.
| 8
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation-in-part (CIP) of co-pending U.S. patent application Ser. No. 09/778,294, filed Feb. 6, 2001, which is a divisional of U.S. patent application Ser. No. 09/370,654), filed Aug. 6, 1999 (issued as U.S. Pat. No. 6,258,383), which claims the benefit of U.S. Provisional Patent Application Serial No. 60/096,697, filed Aug. 14, 1998. The present application also claims the benefit of U.S. Provisional Patent Application Serial No. 60/257,013, filed Dec. 20, 2000.
FIELD OF THE INVENTION
[0002] The invention relates to natural dietary supplements and their use. More specifically, it relates particularly to dietary supplements that enhance the activity of the two major classes of white blood cells, namely macrophages and neutrophils. This accentuates the host's natural ability to overcome metabolic insults. In particular, compositions comprising beta glucan and lactoferrin are disclosed.
BACKGROUND OF THE INVENTION
[0003] Nutrition is a critical determinant of immunological competence and of the individual's ability to fight infection from bacterial, viral, or fungal sources, cancer development and to slow the lethal effects of septicemia (sepsis). The health of individuals affected by viral infections, general bacterial infections, antibiotic resistant bacterial infections, fungal infections, cancer, and the proliferation of any bacteria in the blood (septicemia) cannot be overlooked. In particular, pollution, food additives, toxins, the routine use of antibiotics, and bioterrorism have resulted in multiple adverse influences upon health. Among these may be included the proliferation of new, more deadly strains of bacteria and viruses that are resistant to existing treatment, compromised immune systems resulting from chemical pollutants in food, water and air. The continuing widespread use of man-made chemicals in medicine and agriculture reinforces the selective pressures that increase the types and extent of antibiotic-resistant microbes in the environment, which then substantially increases the cost of treating infection.
[0004] Additionally, emotional and physical stresses from the natural effects of aging reduce the effectiveness of the immune system and its role in overcoming these adverse agents. The physiological rigors to which an individual's body is exposed in the modem environment, which include the chemical pollutants and antibiotic-resistant microbes discussed above, indicate the advisability of boosting the immune system's white blood cell interaction to facilitate the body's abilities to resist and cope with infection, and to assist the natural, self-healing processes. Two groups of individuals are particularly susceptible to infection and the side effects of treatment: young children and the aged. These individuals may respond poorly to physiological or environmental challenges because they typically possess immune systems that are, in young children and in the aged respectively, immature or damaged. Consequently, natural fortification of these individuals' white blood cells is particularly desirable.
[0005] The importance of macrophages and neutrophils, the two major classes of white blood cells, is well documented. The basis for elimination of cancer cells, fighting infection, and the prevention and treatment of septicemia is contingent upon the interaction of macrophages and neutrophils. The neutrophil immediately goes to the site of an insult; the outer membrane will burst and then release lactoferrin. The lactoferrin sequesters any free iron available for the pathogens growth as well as starts to degrade the pathogen's outer membrane. In doing so, it marks the intruder for the macrophage to destroy. Without the assistance from the neutrophil the macrophage is severely limited in its efficacy, therefore an abundance of neutrophils along with enhanced macrophages results in much faster elimination of cancer cells, infections, and slowing the progression of any bacterial infection into a lethal toxin cascade that ultimately results in septicemia
[0006] Stimulation of the immune system may occur if the appropriate glycoproteins and proteins are absorbed into an individual's bloodstream. These biomolecules are expensive to obtain, even in the quantities and formats used for experimental demonstrations (Lonnerdal & Iyer, Annu. Rev. Nutr., 15: 93-110, 1995). Attempts to formulate an effective dietary supplement able to generate and maintain a state of white cell equilibrium in an individual have been unsuccessful, leading to the need for the wide variety and potency of antibiotics.
[0007] If the components of a dietary supplement were to possess, in addition to nutritional characteristics, abilities that aid the body's ability to eliminate cancer cells, fight infection, and prevent and treat septicemia, such abilities would naturally prove advantageous for achieving the health and well being enhancing the purposes outlined above.
[0008] As indicated below, those skilled in the art of the respective fields recognize that beta glucan and lactoferrin, are individually able to perform limited beneficial activities of this type (Wang, et al., J. Leuk. Biol., 75: 865-874, 1995; and Burrin et al., Pediatr. Res., 37: 593-599, 1995).
[0009] Beta glucan is a complex sugar (polysaccharide). Beta glucan can be obtained from a wide array of sources such as baker's yeast, fungal cells, mushrooms, barley, and oats. Beta glucans can be characterized by their main chain linkages and by their branching at various positions in the saccharose rings. Beta 1,3 D-glucan, Beta 1-3, 1-4 D-glucan, and Beta 1-3, 1-6 D-glucan are some of the more common types found. Naturally obtained beta glucan contains a mixture of all of the chains in different proportions. For instance, a mixture may have more Beta 1,3 linkages than 1-4 and 1-6 linkages. Different organisms produce beta glucans with different types and distributions of linkages. Most of the scientific literature focuses on the most common form, Beta 1,3 D-glucan. As used herein, “beta glucan” refers to mixtures that can contain one, two, or all three variations. Beta glucans can further be chemically modified, e.g. by sulfation, amination, and cross-linking.
[0010] Research has been reported on some of the beneficial properties of beta glucan. Macrophage activation was reported in vitro using a cross-linked 1,3 beta glucan (Adachi, Y., et al. Chem. Pharm. Bull. (Tokyo) 38: 988-992, 1990). Glucan activated macrophages were reported to enhance host resistance to malignancies (DiLuzio, N. R. et al., The Macrophage in Neoplasia, Academic Press, Inc., 181-198, 1976; Artursson, P. et al., Scand. J. Immunol., 25(3): 245-254, 1987; Reynold, J. A. et al., Infection and Immunity, 30: 51, 1980). Anti-tumor and anti-cancer effects of glucans have been reported (Bomford, R. and Moreno, C., Br. J. Cancer, 36: 41-48, 1977; Bomford, R. and Moreno, C. Dev. Biol. Stand., 38: 291-295, 1977; Morikawa, K., et al., Cancer Res. 45: 1496-1501, 1985; Proctor, J. W. et al., Cancer Treat. Rep. A2(11): 1873-1880, 1978; Proctor, J. W. and Yamamura, Y., J. Natl. Cancer Inst. 61: 1179-1180, 1978). The anti-sepsis properties of glucans have also been reported (Tsujinaka, T. and Yokota, M. K., Euro. Surg. Res., 22: 540-546, 1990; Rasmussen, L. T. and Seljelid, R., Scand. J. Immunol. 32(4): 333-340, 1990; Lahnborg, G. et al., J. Reticuloendomenal Soc., 32: 347-355, 1982; Lahnborg, G. et al., Eur. Surg. Res., 401-408, 1982)
[0011] Lactoferrin is a protein that is secreted in milk, tears, mucus and saliva, and is expressed by white cells at the site of attack by numerous pathogens. A primary function of lactoferrin is to bind iron at the molecular level and thereby act as a highly effective antimicrobial agent. Iron is an essential growth factor for virtually every cell and microorganism, and free iron promotes the growth of pathogens in the intestines (bacteria, fungi, and viruses), permitting invasion of the rest of the body through the intestinal walls (Gillon Ward et al., J. Trauma, Inj. Inf. Critical Care, 41: 356-364, 1996). Lactoferrin is released by neutrophils to absorb free iron that would otherwise be available to bacteria, viruses and fungi for growth. Unlike synthetic antibiotics, to which bacteria may develop resistance through mutation, lactoferrin exerts its bacteriostatic effect as long as the bacteria require iron for growth.
[0012] Additionally, lactoferrin is recognized by specific receptors in mammalian tissues, and upon binding, releases iron to the body for normal, healthy cell growth. Unlike synthetic antibiotics, lactoferrin has the ability to bind iron, transport it and then release the iron specifically to the body's own cells through cell surface lactoferrin receptors. Binding of bovine lactoferrin to B. bifidum and B. breve was about 40-fold higher than binding to Escherichia coli, regardless of the iron saturation level of the lactoferrin (Petschow B W, et al., J. Med. Microbiol., 48(6):541-549, 1999).
[0013] Lactoferrin is a multifunctional protein that is produced in a variety of cell types under different mechanisms of control. It has been demonstrated that lactoferrin plays a central role in the inflammatory defense processes. Released in abundant quantities by neutrophils attracted to the site of an invasion, lactoferrin binds the iron made available by serum and damaged erythrocytes. Monocytes and macrophages ingest the iron-saturated lactoferrin, which has also been implicated in the production of metastable oxygen metabolites associated with bacterial destruction within these blood cells (Wang, et al., J. Leuk. Biol., 75: 865-874, 1995). Lactoferrin also regulates the release of tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) in vivo (Machniki et al, Int. J. Exp. Path., 74: 433-439, 1993). Lactoferrin increases the number of fresh neutrophils in circulation by up to 116% (Zimecki M, Arch. Immunol. Ther. Exp. ( Warsz ), 47(2):113-118, 1999).
[0014] Due to the iron absorption and release functions of this protein, lactoferrin is the body's primary regulator of iron, a major bio-regulator of the digestive tract and a natural bacteriostatic agent having indirect but broad antibiotic effects. Yet the cost and availability of human lactoferrin, purified from human breast milk, restricts its use to research.
[0015] Lactoferrin's iron-binding bacteriostatic effect, coupled with its general abundance in breast milk, has led to numerous studies in new-born mammalian offspring, prompting its incorporation into Japanese baby formula since approximately 1993. Lactoferrin B is an amino terminal peptide of bovine lactoferrin generated by pepsin digestion and has been shown to have a potent bactericidal activity against a diverse range of potentially pathogenic bacteria (Bellamy et al, J. Applied Bacteriol., 73: 472-479, 1992). The importance of lactoferrin in newborn humans for ensuring the appropriate formation and development of the gastrointestinal tract, its bacterial colonization and to enable nutrients to be absorbed effectively has also been demonstrated.
[0016] Many of these functions of lactoferrin are reviewed by Lonnerdal & Iyer ( Annu. Rev. Nutr., 15: 93-110, 1995). Yet these authors note that the relative efficacy of using either lactoferrin from other species, or recombinant human lactoferrin for treatment of humans is unproven. This is because adequate quantities of human lactoferrin have not been isolated to supply clinical studies, and recombinant human lactoferrin will not accurately reproduce the protein's glycan composition.
[0017] Tanaka et al., U.S. Pat. Nos. 5,098,722 and 5,008,120 suggest methods of preparing iron-fortified beverages that contain a solution of purified bovine lactoferrin and provide high bio-availability of iron.
[0018] Tomita et al., U.S. Pat. No. 5,304,633 presents fragments of milk lactoferrin having potent antimicrobial activity. Kunio et al., U.S. Pat. No. 5,576,299 suggests the use of lactoferrin for preventing and treating the opportunistic infections that arise in immuno-compromised individuals. Yamamoto et al., U.S. Pat. No. 5,725,864 offers the use of an iron-binding protein, of which lactoferrin is one of several examples, for inhibiting infection or suppressing growth of human immunodeficiency virus. The protein is administered by diffusion through any of several epithelial membranes, or by injection. Valenti & Antonini, U.S. Pat. No. 5,834,424 proposes the use of compositions containing lactoferrin or other iron-binding proteins for treating Gram-positive bacterial infections.
[0019] Nichols & McKee, U.S. Pat. No. 4,977,137 suggests the use of milk lactoferrin from human and other mammalian sources as a dietary ingredient or supplement. The lactoferrin promoted growth of the gastrointestinal tract of human infants or non-human animals immediately on birth. Konig et al., U.S. Pat. No. 5,466,669 offers an immunostimulatory agent comprising a peptide derived from lactoferrin.
[0020] Headon et al., PCT/US90/02356 and European Patent No. 0 471 011 B1 presents the verified cDNA sequence of human lactoferrin. Kruzel, PCT/US91/01335 offers human lactoferrin expressed from recombinant DNA, its method of production and purification and its use for supplementing the diet with trace elements or as a topical antiseptic. Kruzel et al., PCT/US95/05653 discusses the cloning, expression and uses of recombinant human lactoferrin for retarding food spoilage, as a topical antiseptic, for inhibiting microbial growth in or on a mammal, for regulating iron levels within a mammal or for a nutritional supplement.
[0021] The strongly acidic conditions of the stomach, and the function of the proteolytic enzymes and zymogens produced in the pancreas and acting in the intestines, are well known to inactivate and degrade the delicate structures of proteins, such as the components of the dietary supplements described here. The species-specific glycosylation of lactoferrins from different mammalian sources may provide protection from proteolysis for lactoferrin ingested naturally from maternal milk, and cross-species administration of lactoferrin would be expected to be far less effective (Lonnerdal & Iyer, Annu. Rev. Nutr., 15: 93-110, 1995). Even if the lactoferrin succeeds in reaching the small intestine intact, specific lactoferrin receptors enable human lactoferrin to deliver iron to the mucosal cells of human small intestine, whereas bovine lactoferrin is incapable of doing so (Cox et al., Biochim. Biophys. Acta, 558: 129-141, 1979).
[0022] The gastric survival of bovine lactoferrin has been studied (Troost F J, et al., J. of Nutrition, Aug;131(8):2101-2104, 2001). Gastric survival of bovine lactoferrin, analyzed by gel permeation chromatography under denaturing conditions, was only 62%. Buffering with a gastric pH buffer only increased gastric survival to 64%. Surface plasmon resonance analysis indicated that bovine lactoferrin binds more strongly to salivary agglutinin, especially to high molecular mass glycoprotein, which is a component of the agglutinin (Mitoma M, et al., J. Biol. Chem., 276(21):18060-18065, 2001). Mitoma demonstrated that the binding of bovine lactoferrin to salivary agglutinin was thermostable, and the optimal pH for binding was 4.0. Bovine lactoferrin binding with salivary agglutinin in the mouth results in a more stable lactoferrin component. Mucosal delivery in the mouth is preferred over the gastric delivery of lactoferrin. Accordingly, gastric delivery in the form of an enteral feed preparation or the swallowing of a capsule requires approximately 150% of the amount of lactoferrin that could be delivered directly into the mouth.
[0023] In spite of the knowledge of the beneficial properties of either beta glucan or lactoferrin when used individually, there remains a continuing need for an economical dietary supplement to balance the body's own defense and to provide for white blood cell homeostasis. The components of the supplement must be obtainable from economic and abundant sources, yet remain effective for administration to humans, and preferably to a broad range of recipient mammals. Moreover, such a dietary supplement must be absorbed effectively, without the degradation of protein constituents that is associated with regular digestive processes such as the destruction of delicate immunoglobulins by acids in the stomach.
[0024] The oral cavity contains a plethora of mechanisms to counter the survival of infectious agents that enter through the mouth and nose: secreted with the saliva are broad-spectrum IgA antibodies, lysozyme, and small quantities of lactoferrin, and lymphoid cells entering the oral cavity through the gingiva. In addition, it has recently been recognized that external factors may also deliver signals that modulate immune responses: these factors include cytokines such as the interferons, as well as hormones, growth factors and cellular antigens.
[0025] Studies aimed at preventing allergic inflammation in rodents have indicated that administration of interferon to mice by oral feeding could be as effective as intraperitoneal injection. Thus oral administration of either antigens or cytokines may be capable of modulating a variety of physiological reactions, including immune responses. Possible routes of mediation are: (a) taste buds of the tongue, connected by nerves to hypothalamus collateral centers, control appetite and energy utilization; (b) a spectrum of mucosal and secretory cell types present in the oral cavity that are capable of responding to cytokine or antigen signals and releasing further cytokine messages; (c) epithelial cells of the oral cavity, which are likely to be the natural recipients of signals entering the mammalian mouth: in the adult these would be primarily signals from antigens, whereas for the neonatal mammal important signals would also be received from ingested maternal cytokines and maternal hormones; (d) the submucosal tissue of the oral cavity, which secretes immunoglobulin IgA. Small amounts of either cytokine or antigen may be recognized as antigen by a responsive cell, resulting in immune activation via initiation of the cytokine cascade, whereas large doses or extended administration may induce tolerance: studies have shown that interferon administered in large doses to humans may be less effective than minimal quantities. Thus the response will frequently be individual or case dependent and may be strongly influenced by additional physiological or environmental factors.
[0026] The implications of these immunological studies have been reviewed recently (Georgiades, Biotherapy, 11: 39-51, 1998) with the conclusion that the tolerance phenomenon is not only limited to the oral administration of antigen but may occur when immunization is attempted via any mucosal membrane, such as the nasal tract.
[0027] Thus, despite the research reported to date, there still exists a need for novel nutritional supplement compositions which are effective at stimulating macrophages and neutrophils to achieve a balanced attack on pathogens.
SUMMARY OF THE INVENTION
[0028] Nutritional supplement compositions comprising beta glucan and lactoferrin are disclosed. The compositions can further comprise nutritionally acceptable carriers, diluents, or flavorings. The compositions can be used in a nutritional program to enhance the activity of macrophages and neutrophils, improving the body's ability to fight infection from bacterial, viral, or fungal challenges. The administration of a combination of beta glucan and lactoferrin affords a balanced effect of activated macrophages and an increased number of neutrophils that would not be achieved by the administration of either material alone.
DETAILED DESCRIPTION OF THE INVENTION
[0029] In the light of the conflicting results and controversial hypotheses discussed above, it could be considered counter-intuitive, and certainly unpredictable, to attempt to stimulate or potentiate an immune response by administering cytokines and immunoglobulins orally by means of a combination of beta glucan and lactoferrin.
[0030] The present invention is generally directed towards dietary supplements containing beta glucan and lactoferrin, thus providing an improvement over previous supplements which lacked one or other or both of these components. When absorbed in combination, the effects of beta glucan and lactoferrin on the health and well-being of the recipient are surprisingly beneficial, being greater than would be anticipated from the known properties of each component taken in isolation and including the elimination of cancer cells and tumors, enhancing the body's attack against viral infections, general bacterial infections, antibiotic resistant bacterial infections, and arresting the proliferation of any bacteria in the blood thereby reducing the occurrence of septicemia. Either delivery of the components in the gastro-intestinal tract via a dose specific capsule or absorption of the components in the oral cavity is particularly efficacious: hence the invention includes capsules or the provision of the components in a mucosal delivery format (“MDF”) such as a chewable lozenge.
[0031] Numerous components can solicit responses by the white blood cells; however, only a combination of beta glucan and lactoferrin can enhance both groups of cells and achieve a desired “balanced” effect. The inventive compositions enhance the potency of macrophages along with the number of fresh neutrophils in circulation. This enhancement and balancing of the white blood cell group results in optimum infection fighting, cancer cell reduction, and the elimination of septicemia. The enhancement and balanced effects would not be achived by administration of either component by itself.
[0032] The present invention provides a dietary supplement comprising beta glucan and lactoferrin. For mucosal delivery format, it also provides a composition containing these ingredients, which may also include nutritionally acceptable carriers, diluents and flavorings, a method of administering such a composition in a form appropriate for absorption through the lining of the oral cavity, and a method of eliminating cancer cells and tumors, enhancing the body's attack against viral infections, general bacterial infections, antibiotic resistant bacterial infections, and arresting the proliferation of any bacteria in the blood as an effective preventative and treatment against septicemia.
[0033] Providing the dietary supplement in the form of lozenges which may be dissolved slowly in the mouth may lead to more rapid effects of energizing the white blood cells naturally to keep pathogens in check. Taking a dose of the inventive composition preferably 1-3 times per day, as needed, provides the suggested dietary supplement.
[0034] The invention addresses the requirement for an effective and economical dietary supplement comprising one or more natural stimulators of immune function, elimination of cancer cells, fighting infection, and the prevention and treatment of septicemia. Furthermore, this supplement can be provided in a convenient format that permits absorption of the active components into an individual's bloodstream in a manner that avoids the body's normal digestive mechanisms. Additionally, when mucosal delivery is not available do to the age, condition, or allergy tolerances of the patient, a dose specific capsule can be used to still achieve a beneficial response. The present invention uses both gastrointestinal delivery and emphasizes the efficacy of oral administration of the dietary supplement and promotion of the supplement's efficient absorption through the oral cavity's epithelial lining by presenting the supplement in a mucosal delivery format (“MDF”). Those MDFs of the invention that are presently preferred, e.g. chewable lozenges, also render the dietary supplement of the invention particularly adaptable to self-monitored dosages, and are especially appropriate for regimes of self administration.
[0035] The invention has been found effective for numerous physiological disorders caused by and resulting in a variety of metabolic insults, including routine antibiotic use, toxic pollutants, food additives, stress, and aging.
[0036] Beta glucan from yeast has the highest concentrations of complex polysaccharides or polyglucose. Common baker's yeast ( Saccharomyces cerevisiae ) presently appears to have the greatest benefit, however other beta glucans are found in a variety of fungal cells, including such sources as Maitake mushroom, reishi mushroom, sacred mushroom tea, barley, and oats. Beta glucan attaches to the receptor site on the macrophage, and in doing so activates the macrophage. This provides the host with enhanced protection against viruses and bacteria and other health threats. As the body ages, macrophages become weakened and are much more difficult to stimulate. Supplemental use of this polysaccharide activates the macrophage population and enables the host to overcome metabolic insults.
[0037] Lactoferrin is an iron binding protein that occurs naturally in the body. It is secreted in milk, tears and saliva, and is expressed by white blood cells. Lactoferrin is a biological regulator that performs many important functions in the body. These functions include maintaining a healthy balance in the digestive tract, helping the immune system and promoting healthy cell growth. Dairy cattle currently provide the only cost-effective source of lactoferrin for inclusion into a dietary supplement, even though cows' milk contains a relatively low concentration of lactoferrin. Lactoferrin from cows' milk can be prepared free of lactose; it bioregulates iron, boosts the immune system, balances the digestive tract, increases energy and stamina and promotes cell growth and healing. These broad, beneficial properties are surprising in view of the inability of bovine lactoferrin to bind to the lactoferrin receptors at the surface of the mucosal cells of human small intestine.
[0038] Natural lemon flavor is a further optional component that may be incorporated to promote salivation and to adjust the acidity of the composition in order that solubility, activity and absorption of the components within the oral cavity is enhanced.
[0039] Iron is a key mineral required by all microorganisms for maintenance and growth. Excess iron in the intestines promotes pathogen growth and proliferation. Lactoferrin from cows' milk is partially saturated with iron (approximately 25% of total saturation) providing a dietary source of iron as well as a means of scavenging free iron from the oral cavity and digestive tract. Lactoferrin works on contact to starve pathogens of iron so that the correct balance of beneficial bacteria develops and is maintained in the digestive tract; the growth of harmful bacteria that are poorly adapted to these conditions being inhibited. By sequestering iron and delivering it for use by the cells of the body's internal tissues lactoferrin improves digestion and boosts the body's natural defense mechanisms. This generates more energy and increased stamina for physical activities and optimum health.
[0040] Beta glucan and lactoferrin are presently believed to achieve their optimal effects when dissolved slowly in the mouth, rather than being swallowed directly in the form of a pill or capsule. Slowly dissolving the beta glucan and lactoferrin in the mouth permits their absorption into the capillaries at the surface of the oral cavity's lining, and this is able to occur before the beta glucan and lactoferrin are exposed to the harsh degradatory conditions of the stomach and intestines. For example, bovine lactoferrin is less resistant to degradation in the human digestive tract than is human lactoferrin, and the lactoferrin receptors in the small intestine of humans will not bind bovine lactoferrin. Thus, administration of bovine lactoferrin to humans in a mucosal delivery format, such as a format that enables its absorption through the lining of the mouth, is particularly efficacious. As much as 10% of beta glucan is micronized, thereby allowing more rapid absorption where it can pass directly into the blood through the inner mucosal layer of the mouth.
[0041] Lozenges, in contrast to pills, provide a mucosal delivery format (“MDF”) for constituents (such as beta glucan and lactoferrin) which can be absorbed through the oral mucosal surface. In particular, the lozenges of the instant invention are able to enhance the benefits associated with absorption of appropriate constituents through the oral epithelial mucosa and into the underlying lymphatic system, for they are designed to be dissolved slowly in the mouth and they may also be chewable: such lozenges are therefore a presently preferred MDF. By using a cold-pressing technique to manufacture the lozenges heat degradation of sensitive biological components is minimized. Lozenges are also presently preferable to hard-pressed tablets, for the latter do not dissolve until exposed to the gastric juices of the stomach. Oral administration using lozenges as the mucosal delivery format, but not capsules or hard tablets, allows the lactoferrin to sequester iron in the upper digestive tract and thereby broaden the effect of its bacteriostatic actions.
[0042] The present invention incorporates ingredients derived from yeast and dairy sources. Given the species-specificity of human intestinal lactoferrin receptors and the apparent ease with which antigenic tolerance can be induced in a variety of mammals from rodents to primates, the efficacy of the instant invention in achieving its stated aims is remarkable and unexpected. By administering a combination of yeast beta glucan and bovine lactoferrin, not only are beneficial effects of each component observed, but a synergistic effect is apparent: the results of combined administration are greater than may be accounted for by an additive effect of the individual components. The results observed, and described below in the Examples, may stem not only from the novel combination of ingredients, but also from the manner in which they are administered and the apparent inducement of immunological responses that is possible when such materials are provided in the recommended doses and allowed to be absorbed through the epithelial lining of the oral cavity.
[0043] The individual components of the composition may be obtained from commercial sources: beta glucan (which is dehydrated by standard spray-drying procedures known in the art) from any processing facility approved by the United States Food and Drug Authority (F.D.A.) such as Biopolymer Engineering, Inc. of St. Paul Minn., U.S.A.; lactoferrin from approved manufacturers such as DMV International Nutritionals of Frazier N.Y., U.S.A.; flavors from approved distributors or manufacturers such as Allen Flavors, Inc. of Edison N.J., U.S.A. Manufacturing of the composition, the dietary supplement, and the oral dosage forms can each be performed using standard techniques appropriate for the food or pharmaceutical industries, as at F.D.A. approved facilities such as Biotics Research, Inc. of Rosenberg, Tex., U.S.A.
Inventive Compositions
[0044] The concentrations of composition ingredients are typically expressed in terms of weight percent. The weight percent of a component is determined based on the weight of the entire composition (i.e. the weight of the component is divided by the total weight of the composition, and multiplied by 100%). For example, 10 mg of beta glucan in a 1000 mg total weight composition would be characterized as 1 weight percent beta glucan.
[0045] Generally, the invention is directed towards compositions comprising beta glucan and lactoferrin, and methods for their use. The compositions can be in the form of a liquid, a solid, a capsule, a lozenge, a chewable lozenge, a chewable tablet, a chewable gum, or any other acceptable form. Capsules can be attractive in certain circumstances due to their ease of swallowing. The compositions can be used in baby food preparations. The compositions can be used in enteral feeding preparations where the host is less able to tolerate the fillers and/or flavorings.
[0046] Lozenges are presently preferred to be prepared by cold pressing. Lozenges are presently preferred to have a hardness of about 14 Kp to about 35 Kp.
[0047] Presently preferred embodiments of the invention include compositions and dietary supplements, as described above, prepared in a “mucosal delivery format”; particularly as an oral dosage form that promotes absorption of the dietary supplement's components through the epithelial lining of the oral cavity. Further preferred embodiments are methods for promoting those beneficial effects in mammals described above, in which such oral dosage forms of these compositions and dietary supplements are administered. Examples of oral dosage forms that promote absorption of the dietary supplement's components within the oral cavity are those that encourage retention of the dose within the oral cavity for an extended period, or discourage swallowing of the dose. Dosage forms that are chewable or that are appropriate for sucking are examples; they can be additionally designed to encourage salivation. Such dosage forms include lozenges, particularly chewable lozenges, chewable tablets and chewable gums. The addition of natural or artificial flavoring also encourages retention of the dosage form within the mouth, particularly with children, so that there is greater transfer of the active components through the lining of the oral cavity and into the bloodstream and/or the lymphatic system. Such active components include the constituents of colostrum and the lactoferrin, as described above. The physical size and consistency of the dosage form can also be adapted to prevent premature swallowing of the delivered dose; 30 seconds to ten minutes is the recommended period for which the dose should remain in the mouth for effective absorption, with better effects being observed at the longer retention times. Larger chewable forms are appropriate for animals that would otherwise be likely to swallow such foodstuff with little mastication.
[0048] The compositions can further comprise one or more of the following: nutritionally acceptable carriers, nutritionally acceptable diluents, nutritionally acceptable flavorings, fillers, colorants, binders, and sweeteners. These materials can improve the attractiveness and flavor of the compositions. Examples of these materials include citric acid, sucrose, fruit flavoring, citrus flavoring (such as lemon or orange), silicon dioxide and/or magnesium stearate (as a binder).
[0049] The beta glucan can generally be obtained from any source. Presently preferred sources include mushrooms, yeast, and oats. Yeast cell wall beta glucans are a presently more preferred source. The concentration of beta glucan in the compositions can generally be any concentration. The concentration can be about 1 weight percent to about 10 weight percent, about 1 weight percent to about 5 weight percent, or about 1 weight percent to about 2.5 weight percent. A particular composition can have about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, or about 10 weight percent beta glucan.
[0050] The lactoferrin can generally be obtained from any source. Presently preferred sources include mammals such as cows (bovine), and more preferably bovine milk. The concentration of lactoferrin in the compositions can generally be any concentration. The concentration can be about 0.25 weight percent to about 2.5 weight percent, about 0.5 weight percent to about 2 weight percent, or about 1 weight percent to about 1.5 weight percent. A particular composition can have about 0.25, about 0.5, about 0.75, about 1, about 1.25, about 1.5, about 1.75, about 2, about 2.25, or about 2.5 weight percent lactoferrin.
[0051] A particular composition can be characterized with the concentration of beta glucan in the composition being about 1 weight percent to about 10 weight percent, and the concentration of lactoferrin in the composition being about 0.25 weight percent to about 2.5 weight percent. An additional particular composition can comprise about 1 weight percent beta glucan to about 3 weight percent beta glucan, about 0.5 weight percent lactoferrin to about 1.5 weight percent lactoferrin, and about 5 weight percent nutritionally acceptable flavoring to about 7 weight percent nutritionally acceptable flavoring. A further particular composition can comprise about 2 weight percent beta glucan, about 1 weight percent lactoferrin, and about 5.7 weight percent nutritionally acceptable flavoring.
[0052] A further particular composition can consist essentially of, or can consist of the following components: about 2 weight percent beta glucan, about 1 weight percent lactoferrin, about 5.7 weight percent lemon flavoring, about 50 weight percent mannitol, about 40.8 weight percent sorbitol, and about 0.5 weight percent silicon dioxide.
Inventive Methods
[0053] Any of the above described compositions can be used in the following methods.
[0054] The above described compositions can be used in methods of treating an individual afflicted with cancer, treating an individual infected with bacteria, treating an individual infected with a fungus, treating an individual infected with a virus, and treating an individual afflicted with septicemia. The compositions also can be used as in a method to prevent or delay the onset of a bacterial infection, fungal infection, viral infection, or septicemia in an individual. The individual is preferably a mammal. The mammal can generally be any mammal such as a human, dog, cat, cow, horse, pig, goat, bear, or moose. The mammal is preferably a human.
[0055] Administering the compositions to the individual preferably reduces the amount of cancer, amount of bacteria, amount of fungi, amount of virus, or amount of sepsis in the individual. The reduction is determined by comparing the post-administration amount to the pre-administration amount. The reduction is preferably at least about 10%, at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, and ideally about 100%. Prevention of the onset of a bacterial infection, fungal infection, viral infection, or septicemia is relative to the time of onset of a similar individual who was not administered the composition. The delayed onset time is preferably at least about 1 day, 1 week, 1 month, 1 year, and ideally the onset would not happen to the administered individual in a clinically relevant timeframe.
[0056] In a presently preferred embodiment of the invention, the composition is taken as a nutritional supplement one to three times per day. The lozenge can be chewed for about 30 seconds to about ten minutes to maximize absorption of the active ingredients through the lining of the oral cavity and their absorption into the blood and lymphatic system.
[0057] The following examples are included to demonstrate preferred embodiments of the invention. It should be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.
EXAMPLES
Example 1
Preparation of Lozenge Formulation
[0058] Preparation of the lozenges was performed with precautions against exposure to the powders and dusts that are formed, and particularly against their inhalation. Each of the following powdered ingredients was placed into a commercial mixer: 20 parts beta glucan, 10 parts bovine lactoferrin, 500 parts mannitol, 408 parts sorbitol, 57 parts natural lemon flavor, and 5 parts silicon dioxide. If necessary, the materials were passed through a #10-12 mesh screen to remove aggregates. After 20 minutes of thorough mixing, cold pressing the composition in a tablet press set at a maximum pressure of 6.4 tons yielded lozenges of weight 1000 mg and hardness 25 to 28 Kp. The lozenge can be characterized as containing 2 weight percent beta glucan, 1 weight percent lactoferrin, 50 weight percent mannitol, 40.8 weight percent sorbitol, 5.7 weight percent lemon flavor, and 0.5 weight percent silicon dioxide.
Example 2
Preparation of Capsule Formulation
[0059] Each of the following powdered ingredients were placed into a commercial mixer following the same procedure as described in Example 1, except they were encapsulated in a #2 gelatin capsule: 20 parts beta glucan, 10 parts bovine lactoferrin, and 270 parts filler. After mixing and encapsulating, capsules of weight 300 mg were formed. The lozenge can be characterized as containing about 6.7 weight percent beta glucan, about 3.3 weight percent lactoferrin, and about 90 weight percent filler.
Example 3
Effects of Lozenges on Sinus Infections
[0060] A human female with acute sinusitis and sinus infection sought medical care. Consultation with her physician resulted in the first of a series of prescriptions for antibiotics. After taking the first treatment, a return visit to the physician showed no improvement. A second type of antibiotics was prescribed, again with no improvement. After taking the second treatment without beneficial effect, a third antibiotic was prescribed. After eight weeks without noticeable improvement, the patient started a regimen of taking mucosally delivered lozenges containing 20 mg beta glucan and 10 mg lactoferrin three times per day. After three days of the regimen, the patient experienced considerable relief from inflammation. By the end of the fifth day of the regimen, the infection had been eliminated and the patient had no discomfort or distress.
Example 4
Effects of Lozenges on Terminal Cancer
[0061] A human male patient with terminal pancreatic and liver cancers was discharged from further hospital treatment and was allowed to go home to die. Hospice was called to provide the final in home health treatment, which consisted of monitoring and overseeing the administration of a morphine pump. The patient's wife started him on a regimen of taking mucosally delivered lozenges containing 20 mg beta glucan and 10 mg lactoferrin three times per day. The wife would place a lozenge in his mouth during his brief periods of consciousness. The formulation of the lozenge dissolved easily to provide mucosal delivery. After two weeks of the regimen, the patient was feeling well enough to be taken off of the morphine pump and had resumed some household functions such as driving a car and shopping at the grocery store. Twenty-six days after being taken off of the pump, the cancerous organs finally shut down and the patient died.
[0062] All of the compositions and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the methods described herein without departing from the concept, spirit and scope of the invention. More specifically, it will be apparent that certain agents which are both chemically and physiologically related may be substituted for the agents described herein while the same or similar results would be achieved. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention.
|
Dietary supplement compositions containing beta glucan and lactoferrin are disclosed. The compositions can be formulated as a liquid, tablet, lozenge, gum, or other acceptable forms. The compositions can further contain flavorings, carriers, or diluents. The compositions can be used in a nutritional program to enhance the activity of macrophages and neutrophils, leading to an improved ability to fight infection from bacterial, fungal, and viral challenges.
| 0
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims benefit of U.S. Provisional Application No. 60/192,646, filed Mar. 27, 2000.
BACKGROUND
Gratings can be used for many purposes, including as optical filters. A grating can be formed as a hologram on a substrate. Light which matches the grating is then deflected in a specified way.
Many optical applications such as optical networking, optical switching, projection displays, optical data storage and optical holographic applications, may need to steer an optical beam in a desired direction.
SUMMARY
The present application teaches forming a plurality of stacked adjustable gratings which can be used for beam steering.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects will now be described in detail with reference to the accompanying drawings, wherein:
FIG. 1 shows a single layer crystal beam deflector;
FIG. 2 shows a stacked, positive grating with a number of layers;
FIG. 3 shows an electronically controlled grating system, which forms a virtual grating; and
FIG. 4 shows a composite system of blazed grating/liquid crystal layers, mixed with a liquid crystal virtual grating layer.
DETAILED DESCRIPTION
The present system forms an addressable beam deflector. The addressing may deflect an incoming optical beam to one of a plurality of different steering angles.
A first embodiment comprising a single-layer liquid crystal beam deflector is shown in FIG. 1 . This device includes a substrate of glass or other optically transparent material 100 . The glass is covered with an Indium Tin Oxide (ITO) layer 102 . A layer of Polymethyl methacrylate (PMMA) 104 is formed as blazed grating on the ITO layer 102 . The blazed grating can be formed by direct E beam lithography on the substrate. The E beam lithography may form the PMMA layer into the shape of a grating, having a specified period 131 .
Either one or a number of fiber spacers 112 may cover the PMMA grating. These fiber spacers may be configured to leave a space of 0.25 to 3 microns as the width of cavity used to form the space 126 .
Glass substrate 120 , also having an ITO layer 122 , may cover the spacers 112 . The spacers define a cavity 126 , along with the substrate 120 and substrate 100 .
The cavity is filled with liquid crystal material 128 , preferably a nematic type liquid crystal material 128 . For example, the liquid crystal material may be Merck E7, whose refractive indices at a 633 nm wavelength for extraordinary and ordinary light are respectively 1.737 and 1.5815.
An electrical field is applied between the ITO layer 102 , which is under the grating, and the other ITO layer 122 , which is above the grating.
The electro-optic affect of the nematic liquid crystal 128 changes the orientation of the liquid crystal, and hence the refractive index for extraordinary light, according to the modulation of the driving voltage applied between the ITO layers 102 , 122 . Therefore, the phase information which is applied to the grating 104 depends on the electric field applied between the ITO gratings.
The system can be operated in a binary mode. When an electric field is present, the refractive indices of the PMMA grating 104 and liquid crystal 128 are different. Hence, a strong diffraction is produced by the refractive index/phase difference between the grating and liquid crystal when the voltage is in the off state. The effective diffraction efficiency may be determined by the parameters of the blazed grating, such as grating depth, grating period, and blaze profile.
An electric control element 131 is used to apply an electric field between the substrates 100 , 120 . When the electric field is applied between the electrodes, the refractive index of the liquid crystal is decreased. At a specified driving voltage, “index matching” occurs between the PMMA material 104 , and the liquid crystal 128 . When this happens, the entire liquid crystal/PMMA composite grating structure can then be considered as an optically flat plate. Little or no diffraction occurs in this state.
Hence, the device can be viewed as an electrically controlled binary switch. The incident beam can either be deflected when in the off state, or undeflected when in the on state.
Moreover, this device may work preferentially for extraordinary light, and hence form a polarized beam deflector. The incident light 130 needs to have a polarization direction that is the same as the liquid crystal extraordinary light direction, which is also the “rubbing” direction for the homogeneous alignment configuration. The rubbing direction can be established by rubbing one of the glass plates, to cause the liquid crystal to align along the specified direction.
FIG. 2 shows a system that allows controlling the system to deflect the beam to multiple angles. Several layers 200 , 210 of the LC/PMMA composite blazed grating are formed. Each of these layers may be of the general structure shown in FIG. 1 . Each of a plurality of the gratings may have different grating periods ( 131 in FIG. 1 . One embodiment may use a stack that has the period of the top grating 250 being double the period of the bottom grating 252 . This may make all steering angles clearly resolvable.
Each layer may effectively have different driving conditions selected by the electronic control structure that is associated with the layer. Later 200 includes an associated electronic control structure 201 . Layer 210 includes an associated electronic control structure 211 . The two control structures can be the same so long as they can provide separate driving voltages to the respective gratings. By driving the layers in this way, multiple steering angles may be achieved. The available number of steering angles is 2 N , where N is the number of stacked layers. In a dual layer system such as in FIG. 2, the output can be in one of four different directions 220 , 222 , 224 , 226 , as shown. The direction of the outputs depends on the driving condition combinations. The first layer 220 deflects the light 230 into one of two different directions 232 , 234 . The second layer 210 deflects each of these two beams in one of two different directions. Beam 232 can be deflected as either direction 220 or 224 . Seam 234 can deflect into either direction 222 or 226 .
Similarly, a four layer embodiment may provide 16 dynamically addressable angles.
In order to increase the number of layers beyond the four layers which have been described above, the performance of each individual layer may need to be further optimized. The optimization can be done by fine-tuning the PMMA blazed grating fabrication process. Also, improving the blaze profile and depth control can allow an increase the number of layers that may be deposited.
In another embodiment, anti reflection coatings may be deposited on each layer in order to reduce scattering inside the stacked layers. Another improvement may use a specific liquid crystal material that has improved index matching with the PMMA.
Another embodiment is shown in FIG. 3 . In this embodiment, a grating is formed electrically. The electrically formed grating is called a virtual grating. This may use a cascading approach to form an electrically generated blazed grating as described in Resler et al “High Efficiency Liquid Crystal Optical Phased array beam steering: Optics Letter, Vol 21, pp 689-691, and Wang et al, “Liquid Crystal on Silicon Beam deflector, SPIE, Vol 3633, PP 160-169.
FIG. 3 shows the operation. Two cover glass substrates 300 , 310 are formed with patterned electrodes 302 , 304 thereon.
A liquid crystal layer is used to build up a virtual blazed grating inside the liquid crystal medium. Appropriate voltages are assigned along the electrodes to form virtual blazed gratings in the liquid crystal. The assignment of appropriate voltages may generate a device which can be addressed to deflect beams into multiple angles.
It may be easiest to make this electrically generated blazed grating with a relatively fine scanning and hence a relatively small angle. Therefore, this system may operate best when used as a “fine” scanning component. In contrast, the liquid crystal/PMMA blazed grating may form a normally small period. This may be used as the coarse scanning component.
The embodiment shown in FIG. 4 combines a four stacked layer blazed grating/LC coarse scanning component, with the virtual grating layer fine scanning component described with reference to FIG. 3 . The composite structure includes 4 layers of PMMA blazed grating/LC materials 400 , 402 , 404 , 406 , and a single layer 410 of the virtual electrically generated blazed grating. This may yield a steering device with a large number of addressable angles.
For example, The period of the electrically generated grating can be programmed to 80 microns, 160 microns, 320 microns, 640 microns and 1280 microns. This system forms addressable angles which is 16·2 5 =512. In the embodiment of FIG. 2, these many directions would require nine layers of liquid crystal/PMMA grating. The hybrid approach may reduce the number of layers, hence increasing the throughput and simplifying the final device.
Although only a few embodiments have been disclosed in detail above, other modifications are possible. For example, while the above has described using nematic liquid crystal, ferroelectric liquid crystals may be used in order to provide a faster switching speed. While the grating is described as being formed from PMMA, any material can be used to form the gratings, but preferably an etchable material.
All such modifications are intended to be encompassed within the following claims, in which:
|
A system of beam steering using electrical operation. A first system provides a grating and a liquid crystal material. When the liquid crystal is unenergized, there is a mismatch between the liquid crystal and the grating, causing the grating to diffract the light in a specified direction. The liquid crystal is energized to match its index of refraction to the grating. Then, the light is not diffracted by the grating, and hence travels in a different direction then it would when the liquid crystal was not energized. Another, finer system, forms electrically generated gratings using a liquid crystal material.
| 6
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to blowing agent modifiers and their use. More specifically, the present invention is directed to blowing inhibitors and accelerators used to control chemical embossing of various coverings.
2. Description of Related Art
Chemical embossing has been used to create textured surface coverings for over 35 years and is well known in the art. The process of chemical embossing is described in U.S. Pat. No. 3,293,094 issued Dec. 20, 1966 (the “Nairn patent”) and is herein incorporated by reference in its entirety. The Nairn patent discloses a process wherein a resinous composition (also referred to as a foamable polymer) containing a blowing agent mixed with a catalyst is deposited on a backing layer. The resinous layer is gelled at a temperature below the decomposition temperature of the blowing agent. An ink layer is deposited onto the gelled resinous layer by conventional printing or transfer methods. The resinous layer and ink layer form a chemical embossing layer. An optional wear layer may be deposited over the ink layer.
The ink layer includes regions containing a modifier that partially covers the resinous layer in a repeating or random pattern according to the desired design. The modifier diffuses into the gelled resinous layer directly below the modifier. The layers are then heat treated at a temperature sufficient to fuse the resinous layer and to decompose the blowing agent in the regions permeated by the modifier. The decomposition of the blowing agent creates gas pockets or bubbles in the foamable polymer that increase the thickness of the resinous layer in the permeated regions. The regions unaffected by the modifier do not expand as much as the permeated regions resulting in a textured surface containing expanded and substantially unexpanded regions in a pattern corresponding to the modifier pattern in the ink layer.
FIG. 1 is a cross-sectional schematic diagram of a surface covering described by Nairn prior to decomposition of the blowing agent. The surface covering 100 comprises a base layer 120 sandwiched between a backing layer 110 and an ink layer 130 . An optional wear layer 140 covers the ink layer 130 and provides for increased wear and stain resistance for the surface covering 100 . The base layer 120 comprises a resinous composition and a blowing agent. The ink layer 130 includes regions 135 containing a modifier that diffuses into the base layer 120 creating permeated regions 125 in the base layer 120 .
FIG. 2 is a cross-sectional schematic diagram of a surface covering 200 described by Nairn after decomposition of the blowing agent has produced expanded regions 222 in the surface covering. The expanded regions 222 correspond to the permeated regions 125 of the un-expanded surface covering and are in register with the portions 135 of the ink layer 130 containing the modifier. As a result, the expanded surface covering 200 has a textured surface 250 arising from the variation in the base layer thickness between expanded regions 222 and un-expanded regions 224 of the base layer 220 .
The selection of components comprising the embossing composition containing the modifier depends inter alia on the compositions of the blowing agent and the base layer resin composition. The Nairn patent discloses a simple test wherein candidate embossing compositions are deposited on a gelled base layer followed by heat treatment sufficient to fuse the base layer and decompose the blowing agent.
One blowing agent described by Nairn is azodicarbonamide. Azodicarbonamide decomposes between about 195-205° C. The decomposition temperature may be lowered by adding a catalyst to the blowing agent. An example of a catalyst is ZnO.
Improved embossing compositions are disclosed in U.S. Pat. Nos. 5,336,693 issued Aug. 9, 1994, 5,531,944 issued Jul. 2, 1996, and 5,712,018 issued Jan. 27, 1998 (collectively referred to as the “Frisch patents”) and are herein incorporated by reference in their entirety. The Frisch patents disclose an embossing composition comprising an aqueous suspension wherein the modifier is uniformly dispersed in the suspension as a substantially insoluble particulate solid.
U.S. Pat. Nos. 5,728,332 issued Mar. 17, 1998 and 5,733,630 issued Mar. 31, 1998 (collectively referred to as the “Frisch et al. patents”) disclose an embossing composition incorporating modifiers that suppress the decomposition of the blowing agent and modifiers that accelerate the decomposition of the blowing agent and are herein incorporated by reference in their entirety.
The interaction between the blowing agent and modifier is sufficiently complex that empirical tests such as the test described by Nairn must be used to screen and confirm the effectiveness of the ink compositions. Such tests, however, cannot provide information relating to the mechanism by which the modifier affects the decomposition of the blowing agent nor whether the modifier acts directly on the blowing agent or on the accelerator. Although there are numerous compositions developed through empirical testing that are adequate for the manufacture of textured surface coatings, there still exists a need for compositions that allow for more accurate and precise control of the texturing process.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a new class of modifiers capable of inhibiting the activity of the catalyst and to provide a method for discovering such modifiers with determinable modifying characteristics.
One embodiment of the present invention is directed to a modifier for controlling decomposition of a blowing agent, the blowing agent characterized by a decomposition temperature, the modifier comprising a catalyst having an effective capability to reduce the blowing agent decomposition temperature and an organo-silane adsorbed onto the catalyst, the organo-silane capable of inhibiting the effectiveness of the catalyst.
Another embodiment of the present invention is directed to a gel layer for forming a chemical embossing layer of a multi-layer covering comprising: at least one foamable polymer; a blowing agent characterized by a decomposition temperature, the blowing agent capable of evolving gas and forming a plurality of bubbles in the foamable polymer during decomposition thereof; a catalyst capable of reducing the decomposition temperature of the blowing agent; and an organo-silane capable of modifying the capability of the catalyst to reduce the decomposition temperature of the blowing agent.
Another embodiment of the present invention is directed to a method for controlling decomposition of a blowing agent catalyzed by a catalyst, the blowing agent and catalyst mixed in a foamable polymer of a chemical embossing layer, the method comprising the steps of modifying the catalyst with an organo-silane and heating the chemical embossing layer, whereby the organo-silane regulates the decomposition of the blowing agent by the catalyst.
Another embodiment of the present invention is directed to a method of identifying a modifier for controlling activity of a catalyst for decomposition of a blowing agent, the method comprising the steps of: adsorbing a test compound onto the catalyst; measuring a decomposition temperature of the blowing agent heated in contact with the catalyst; and identifying the test compound as a modifier based on the measured decomposition temperature.
These above objects as well as other objects and features of the present invention will appear from the following description in which the preferred embodiments are set forth in detail in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional schematic diagram of a surface covering prior to decomposition of the blowing agent;
FIG. 2 is a cross-sectional schematic diagram of a surface covering after decomposition of the blowing agent;
FIG. 3A shows spectra from diffuse reflectance infrared spectroscopy (DRIFT) of ZnO powder with and without TT100 surface treatment;
FIG. 3B shows DRIFT spectra of ZnO powder with and without Z6030P treatment;
FIG. 3C shows DRIFT spectra of ZnO powder with and without fumaric acid treatment;
FIG. 3D shows DRIFT spectra of ZnO powder with and without Z6020P treatment;
FIG. 3E shows DRIFT spectra of ZnO powder before and after ethanol washing;
FIG. 3F shows DRIFT spectra of ZnO powder as-received and after drying at 100° C.;
FIG. 4 shows a thermogravimetric analysis (TGA) plot of treated ZnO powders mixed with azodicarbonamide in di-isononyl-phthalate plasticizer according to the present invention;
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The structure and function of the preferred embodiments of the present invention can best be understood by reference to the foregoing drawings and following description. The reader will note that the same reference designations appear in multiple locations. Where this is the case, the numerals refer to the same or corresponding structure in those locations.
The inventors of the present invention have discovered that modifiers may be classified into two categories: modifiers that affect blowing agent decomposition by surface absorption onto the catalyst; and modifiers that affect blowing agent decomposition by mechanisms other than surface absorption onto the catalyst.
The candidate modifier adsorbed onto the catalyst may inhibit or accelerate the catalyst or may no have an effect on the decomposition temperature of the blowing agent. An inhibitor is commonly referred to as a compound or composition that, when mixed with the blowing agent (the mixture of blowing agent and catalyst) modifies the decomposition temperature to a range between the pure azodicarbonamide decomposition temperature and the decomposition temperature of the azodicarbonamide/catalyst mixture. An accelerator is commonly referred to as a compound or composition that, when mixed with the blowing agent (the mixture of blowing agent and catalyst) lowers the decomposition temperature to a temperature less than the decomposition temperature of the azodicarbonamide/catalyst mixture. A modifier, as used herein, refers to compositions that affect the decomposition temperature of the blowing agent and includes both inhibitors and accelerators.
The present invention provides for a quantitative ranking of the effectiveness of candidate modifiers in contrast to the simple categorization (the modifier is effective or is not effective) of the Nairn test. Moreover, the measured decomposition temperature may be used to determine the appropriate process temperatures for the chemical embossing process. The relative simplicity of the present invention also allows for rapid screening of candidate modifiers.
In particular, a method for identifying such modifiers and their mechanism has been developed. In one embodiment of the present invention, a candidate modifier is mixed with the catalyst as a solution (if both catalyst and candidate modifier are soluble in the solvent) or a suspension (if either the catalyst or candidate modifier remains as a particulate in the solution). In a preferred embodiment, the catalyst is ZnO particles having a median particle size less than 1000 nm and more preferably less than 250 nm. The solvent is removed using any of the techniques known to one of skill in the art, such as drying at room temperature or at 100° C.
The dried sample may be analyzed using diffuse reflectance infra-red spectroscopy (DRIFT) as known to one of skill in the art. DRIFT analysis may indicate whether the candidate modifier has adsorbed onto the surface of the catalyst as indicated by the presence of a C—H bond stretching mode commonly associated with surface adsorption of an organic molecule in the infra-red region of the electromagnetic spectrum. The presence of such a bond stretching mode may indicate that the modifier has adsorbed onto the catalyst and may be capable of acting as a modifier to the catalytic properties of the catalyst.
In one embodiment for further evaluating the catalyst and modifier, the dried sample is mixed with the blowing agent as known to one of skill in the art. In another embodiment, the dried sample is mixed with a blowing agent and a plasticizer such as, for example, di-isononyl-phthalate. In a preferred embodiment, the blowing agent is azodicarbonamide. Azodicarbonamide decomposes between about 195-205° C. When ZnO is mixed with azodicarbonamide, the decomposition temperature of the mixture may be lowered by 10-25° C.
The decomposition temperature of the dried sample/blowing agent mixture is determined by thermogravimetric analysis (TGA). As known to one of skill in the art, TGA monitors the mass of a sample while the sample is heated. When the blowing agent begins decomposition, the mass of the sample will decrease. The temperature where the sample mass rapidly decreases is referred to as the decomposition temperature of the sample. If the candidate modifier is ineffective, the measured decomposition temperature of the sample should be close to the decomposition temperature of the blowing agent/catalyst mixture. If the candidate modifier acts as an inhibitor, the measured decomposition temperature will be higher than the blowing agent/catalyst mixture but less than the decomposition temperature of the pure blowing agent without the catalyst.
A new class of modifiers have been discovered by the inventors using an embodiment of the present invention. The inventors have found that organo-silanes are effective inhibitors. Typical examples of organo-silane structures are:
R 1 —Si—(OR 2 ) 3 or R 1 R 3 Si—(—OR 2 ) 2
where R 1 and R 3 are aliphatic residues or a functionalized organic substituent and R 2 is an aliphatic residue. More particularly, the functionalized organic substituent of R 1 and R 3 may be an aliphatic group, an aromatic group, a polar group, a non-polar group, a vinyl group, an acrylic group, an amino group, a styryl-amino group, a mercapto group, or a phenyl-amino group. The aliphatic residue of R 2 may be a sec-butyl group, a n-butyl group, an isopropyl group, a n-propyl group, an ethyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an isomer of any of such groups, a high molecular weight residue of any of such groups, or a mixture thereof. In addition, the aliphatic residue of R 1 , R 2 , and R 3 may also be any common linear or branched aliphatic residues. R 1 and R 3 of the foregoing organo-silanes may also be the same aliphatic residue. The organo-silanes may be neat (not hydrolyzed), partially or completely hydrolyzed. In an alternate embodiment, the organo-silane may be oligomerized.
In one embodiment of the present invention, the organo-silane is N-(beta aminoethyl)-gamma-aminopropyltrimethoxysilane available as Z6020P from Dow Corning of Midland, Mich. In another embodiment, the organo-silane is a methacrylate functional silane coupling agent available as Z6030P from Dow Corning of Midland, Mich. Both Z6020P and Z6030P are solutions of partially hydrolyzed organo-silanes.
When the catalyst is pre-treated with either of the above-mentioned organo-silanes, the decomposition temperature of a blowing agent mixture containing the pre-treated catalyst is higher than the decomposition temperature of a blowing agent mixture containing the un-treated catalyst, indicating the effectiveness of the organo-silanes as modifiers for chemical embossing layers. Neither of the above-mentioned organo-silanes, however, exhibit any effectiveness as a modifier when characterized by the Nairn test. One skilled in the art following the Nairn test would presumably exclude both of the above-mentioned organo-silanes from further investigation as a modifier.
In a preferred embodiment, the organo-silane is n-octyltriethoxy silane. In contrast to Z6020P and Z6030P, adsorption onto the catalyst prior to incorporation of the catalyst into the gel layer is not required for n-octyltriethoxy silane. Instead, n-octyltriethoxy silane may be applied with the ink layer and allowed to diffuse into the gel layer. When used in its unhydrolyzed state, n-octyltriethoxy silane acts as an inhibitor. When prehydrolyzed, however, n-octyltriethoxy silane acts as an accelerator.
The invention having been described, the following examples are presented to illustrate, rather than to limit the scope of the invention. Examples 1 through 3 illustrate the modifiers and methods for characterizing the effectiveness of the modifiers according to the present invention.
EXAMPLE 1
Surface Treated Powder Catalysts
Adsorbent solutions were prepared by mixing or dissolving a test compound (or “adsorbent”) in HPLC-grade ethanol available from Aldrich Chemical Company, Inc. of Milwaukee, Wis. Table 1 summarizes the five adsorbent solutions used in this Example. The five adsorbent solutions included: one control solution of ethanol; two solutions, each containing a known modifier; and two solutions, each containing a previously unknown modifier. The two known modifiers are fumaric acid and tolyltriazole. The tolyltriazole (TT100) is a mixture of 4- and 5-methyl isomers of methylbenzotriazole and is available from PMC Specialties Group, Inc. of Westlake, Ohio. The two previously unknown modifiers are pre-hydrolyzed organo-silane mixtures available from Dow Corning of Midland, Mich. The solution designated Z6020P in Table 1 is a 50:50:5 solution of Z6020 pre-hydrolyzed organo-silane, methanol, and water, respectively. Z6020 is a diaminofunctional silane, N-(beta aminoethyl)-gamma-aminopropyltrimethoxysilane, normally used as a coupling agent. The solution designated Z6030P in Table 1 is a 50:50:5:1 solution of Z6030 pre-hydrolyzed organo-silane, methanol, water, and acetic acid, respectively. Z6030 is a methacrylate functional silane coupling agent.
TABLE 1
Adsorbents Concentrations in Adsorbent Slurries
Test Adsorbent
g per 100 g of Ethanol
μmoles
TT100 tolyltriazole mixture
0.6
4511
Z6020P
0.3
1666
Z6030P
0.3
1456
Fumaric Acid
0.3
2586
Control (with no adsorbent)
—
—
ZnO powder was mixed into each adsorbent solution at a ZnO-to-solution weight ratio of 30:70 for all test adsorbents. The ZnO powder was Kadox 911™, available from Zinc Corp. of America of Monaca, Pa. and had a median particle size of 0.12 um. The ZnO slurries were mixed in wide mouth jars by a magnetic stirrer for 24 hours. After the mixing, the ZnO slurries were allowed to settle for a pre-determined period of time, for example, until clear supernatants formed in all of the test samples. The supernatants were pipetted from the jars and retained for analysis by gas chromatography. Fresh ethanol was added to the ZnO sediment in each jar. The samples were re-agitated and allowed to settle for a pre-selected period of time. The re-agitation and washing processes were repeated a total of five times in an attempt to remove all but the most strongly chemisorbed species (i.e., chemical adsorption) from the mixtures. After the final washing, the ZnO powders were dried in air in open jars in a hood for approximately one month. A portion of each treated ZnO powder was separately “dried” in a forced air oven at about 100° C. for 3 hours.
Both oven-dried and ambient-dried powders were analyzed for organic surface coverage by diffuse reflectance infrared spectroscopy (DRIFT). FIG. 3A shows the DRIFT spectra of ZnO powder mixed in the TT100 solution and powder that was dried in the as-received condition. The aliphatic C—H bond stretching is evident in the TT100 DRIFT spectra but is absent in the control spectra, indicating adsorbed TT100 on the ZnO powder. FIG. 3B shows the DRIFT spectra of ZnO powder mixed in the Z6030P solution and powder that was dried in the as-received condition. The aliphatic C—H bond stretching is evident in the Z6030P spectra, indicating adsorbed Z6030 on the ZnO powder. FIG. 3C shows the DRIFT spectra of ZnO powder mixed in the fumaric acid solution and powder that was dried in the as-received condition. The aliphatic C—H bond stretching is evident in the fumaric acid spectra, indicating adsorbed fumaric acid on the ZnO powder. FIG. 3D shows the DRIFT spectra of ZnO powder mixed in the Z6020P solution and powder that was dried in the as-received condition. The aliphatic C—H bond stretching is evident in the Z6020P spectra, indicating adsorbed Z6020 on the ZnO powder. FIG. 3E shows the DRIFT spectra of ZnO powder mixed in the control solution and powder that was dried in the as-received condition. FIG. 3F shows the DRIFT spectra of the as-received ZnO powder dried at room temperature and at 100° C. The spectra in FIGS. 3E and 3F show no evidence of organic infrared (IR) absorption peaks.
The treated ZnO powders were slurried in di-isononyl-phthalate plasticizer (DINP), available from Aldrich Chemical Co., Milwaukee, Wis., together with a blowing agent such as, for example, azodicarbonamide powder (such as Celogen AZ 3001 available from Uniroyal Chemical Co., Middlebury, Conn.) at a ratio of 1.2 g ZnO:1.5 g azodicarbonamide:7.3 g DINP. The slurries were stirred by hand and allowed to set in an ultrasound bath for 2 hours to insure uniform dispersion. Thermogravimetric analysis (TGA) under a 20° C./min heating rate and a 50 cc/min air purge was performed on each of the slurries.
FIG. 4 shows the TGA of the treated ZnO powders slurried with azodicarbonamide blowing agent in DINP plasticizer according to the present invention. As shown in the FIG. 4, the decomposition of the azodicarbonamide blowing agent is readily visible in all of the TGA profiles as a sudden autocatalytic weight loss. The onset of the decomposition temperature ranged from about 170° C. to 230° C. depending on the absorbent.
Table 2 summarizes drying conditions and experimentally observed decomposition temperature of azodicarbonamide in the presence of the treated ZnO powders.
TABLE 2
Effects of Adsorbent-Treatment of ZnO Powder Catalyst on Blowing
Agent Decomposition Temperature
Onset of Decomposition (° C.)
Adsorbent
Dried at ambient
Dried at 100° C.
TT100
197
196
Z6030P
196
197
fumaric acid
184
183
Z6020P
190
189
control: ethanol
183
182
control: as received
—
183
Table 2 indicates a decomposition temperature dependence on the absorbent type. Drying conditions, however, showed no significant effect on the decomposition temperature. The control (no absorbent) powder exhibited the lowest decomposition temperature indicating the efficiency of the pure ZnO powder as an accelerator for the azodicarbonamide blowing agent. The Z6020 and Z6030 prehydrolyzed organo-silanes modified or “inhibited” the action of the ZnO accelerator as reflected by the higher decomposition temperatures of the Z6020 and Z6030 absorbents. Furthermore, the Z6030 absorbent appears to be a more efficient inhibitor than the Z6020 absorbent as indicated by the higher decomposition temperature of Z6030-treated powder relative to the decomposition temperature of the Z6020-treated powder. The Z6030 absorbent inhibited the decomposition of the blowing agent until 196° C. and appeared to be as efficient as the known inhibitor TT100.
The difference between the TT100 decomposition temperature of 196° C. and the fumaric acid decomposition temperature of 184° C. strongly suggests a different inhibitor mechanism for the two known inhibitors. Absorption of the TT100 directly onto the ZnO accelerator appears to inhibit the action of the accelerator and thereby raise the decomposition temperature of the blowing agent to 196° C. Absorption of fumaric acid onto the ZnO accelerator, however, does not appear to appreciably increase the decomposition temperature. Therefore, the present invention is capable of distinguishing inhibitors that operate via absorption onto the accelerator surface from inhibitors that operate via a different mechanism.
The ability of the present invention to screen for candidate inhibitors is demonstrated by the Z6030 and Z6020 pre-hydrolyzed organo-silanes. Neither absorbent is known in the prior art as a blowing agent inhibitor. Table 2 indicates that both Z6030 and Z6020 absorbents act as blowing agent inhibitors. Furthermore, the present invention is capable of providing a quantitative ranking of the effectiveness of the absorbent as reflected by the different decomposition temperatures of the absorbents.
EXAMPLE 2
Evaluation Of Test Absorbents
The effectiveness of the test absorbents was evaluated using the test described by Nairn wherein candidate inhibitors were printed or painted onto a gelled plastisol containing a blowing agent. The painted plastisol was heated to fuse the plastisol and decompose the blowing agent.
Approximately 1 ml of a concentrated (approximately 50% active compound) Z6020P solution was placed onto a gelled layer of PVC plastisol containing azodicarbonamide and ZnO. Similarly, approximately 1 ml of a concentrated (approximately 50% active compound) Z6030P solution was placed onto a gelled layer of PVC plastisol containing azodicarbonamide and ZnO. Approximately 1 g of TT100, a solid powder having a melting temperature of about 80° C., was placed onto a gelled layer of PVC plastisol containing azodicarbonamide and ZnO. The samples were placed in an oven with an observation port and were heated to 400° F. for about 2 minutes.
The TT100 melted and expansion (foaming) of the gelled layer was inhibited in the area immediately underneath the melted TT100. The results for the TT100 sample are consistent with the known inhibition properties of TT100 and confirm the effectiveness of the Nairn test for inhibitors.
The Z6020 and Z6030 samples, on the other hand, did not inhibit the expansion of the gelled plastisol layer.
In a second experiment, solutions containing 0.6 g absorbent per 100 ml ethanol were prepared. Approximately 1 ml of each solution was placed onto the gelled PVC layer containing azodicarbonamide and ZnO. The ethanol was allowed to evaporate at room temperature followed by heat treatment at 400° F. for about 2 minutes. The TT100 inhibited the expansion of the gelled PVC layer in the area immediately underneath the TT100. The Z6020 and Z6030, however, did not appear to inhibit the expansion of the PVC layer.
In a third experiment, un-hydrolyzed Z6020 and Z6030 were applied to the surface of the PVC plastisol containing azodicarbonamide and ZnO. The samples were heated to 400° F. for about 2 minutes. No inhibition of the plastisol expansion was observed for either of the un-hydrolyzed versions of Z6020 and Z6030.
According to the results of this Example, Z6020 and Z6030 would not be considered inhibitors under the Nairn test. The results of Example 1, however, show that Z6020 and Z6030 are inhibitors for the azodicarbonamide/ZnO blowing agent. Therefore, the methods of the present invention have proven that the Nairn test cannot identify all possible inhibitors by identifying inhibitors that fail the Nairn test.
EXAMPLE 3
Not all “known inhibitors” of the prior art perform their inhibition function through adsorption. For example, fumaric acid adsorbs onto the ZnO catalyst but when the ZnO powder is pre-treated with fumaric acid, no inhibition occurs. Furthermore, certain compounds such as pre-hydrolyzed organo-silanes (non-traditional inhibitors) can be made to inhibit decomposition of the azo compounds through adsorption and pre-treatment of ZnO powder thereby. From these findings, it is apparent that other compounds, many of which would be unrecognizable as blowing inhibitors to those skilled in the art, would also reduce the efficiency of the blowing catalysts when such compounds are adsorbed onto the blowing catalysts. Finally, not all traditional inhibitors reduce the efficiency of the blowing catalysts, which indicates that certain types of inhibition reactions do not occur solely by passivation of the surface of the catalyst. Accordingly, the choice of a suitable inhibiting adsorbent is not obvious when considering the compounds from the list of known inhibitors for chemical embossing.
Various embodiments of the present invention have been described. The descriptions are intended to be illustrative of the present invention. It will be apparent to one of skill in the art that modifications may be made to the invention as described without departing from the scope of the claims set out below. For example, it is to be understood that although the present invention has been described using the organo-silanes and azoles as exemplary blowing inhibitors, any other substance that may adsorb onto the blowing catalyst and inhibit catalytic activity thereof may be used as the blowing inhibitor of the present invention.
While the foregoing description and drawings represent the preferred embodiments of the present invention, it will be understood that various additions, modifications and substitutions may be made therein without departing from the spirit and scope of the present invention as defined in the accompanying claims. In particular, it will be clear to those skilled in the art that the present invention may be embodied in other specific forms, structures, arrangements, proportions, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, and not limited to the foregoing description.
|
The present invention relates to a new class of blowing inhibitors and a method for discovering such inhibitors with determinable inhibition activities. The new class of blowing inhibitors are organo-silanes that may be directly adsorbed onto active catalytic sites of blowing catalysts and that can inhibit the thermo-catalytic efficiency of such catalysts.
| 8
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.