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FIELD OF THE INVENTION
[0001] Embodiments of the present invention are directed to cooling of rack-mounted devices, and more particularly to a data center infrastructure having a cooling system.
BACKGROUND OF THE INVENTION
[0002] Electronic equipment racks generally are designed to receive a number of electronic components arranged vertically in the rack, mounted on shelves, and/or to front and rear mounting rails. The electronic equipment may include, for example, printed circuit boards, communications equipment, computers, including computer servers, or other electronic components.
[0003] Electronic equipment housed in racks produces a considerable amount of heat, which undesirably affects performance and reliability of the electronic equipment. Often the heat produced by the rack-mounted components is not evenly distributed in the racks. Temperature gradients causing elevated inlet temperatures at tops of racks, for example, reduce equipment reliability substantially. Equipment reliability may be reduced by as much as half the reliability of specific equipment function for each 10° F. rise in temperature. Accordingly, rack-mounted computer systems typically require effective cooling systems to maintain operational efficiency. Cooling can be accomplished by introducing cooled air into an equipment rack causing the air to flow through equipment in the rack and exit the rack at an increased temperature, thereby removing some of the heat. The heat removed from the rack is typically returned into the room containing the racks and the entire room is cooled using a relatively large air conditioning system.
SUMMARY OF THE INVENTION
[0004] A first aspect of the present invention is directed to a modular data center. The modular data center includes a plurality of racks, each of the racks having a front face and a back face, wherein the plurality of racks is arranged in a first row and a second row, such that the back faces of racks of the first row are facing the second row, and the back faces of the racks of the second row are facing the first row. The data center also includes a first end panel coupled between a first rack of the first row and a first rack of the second row, the first end panel having a bottom edge and a tope edge. Further, the data center includes a second end panel coupled between a second rack of the first row and a second rack of the second row, the second end panel having a top edge and a bottom edge, and a roof panel is included to couple between the top edge of the first panel and the top edge of the second panel.
[0005] The modular data center can be designed so that the roof panel is coupled to a top portion of at least one rack of the first row and to a top portion of at least one rack of the second row, such that the roof panel, the first end panel, the second end panel, and the first and second rows of racks form an enclosure around an area between the first row of racks and the second row of racks. The plurality of racks can further include cooling equipment that draws air from the area, cools the air and returns cooled air out of the front face of one of the racks. At least one of the first end panel and the second end panel can include a door. Further, at least a portion of the roof panel can be translucent. The modular data center can have at least one rack that includes an uninterruptible power supply to provide uninterrupted power to equipment in at least one other rack of the plurality of racks. The first row of racks in the modular data center can be substantially parallel to the second row. In addition, the modular data center can be designed such that one of the plurality of racks includes cooling equipment that draws air from an area between the first row and the second row, cools the air and returns cooled air out of the front face of one of the racks.
[0006] Another aspect of the present invention is directed to a method of cooling electronic equipment contained in racks in a data center. The method includes arranging the racks in two rows, including a first row and a second row that is substantially parallel to the first row, with a back face of at least one of the racks of the first row facing towards a back face of at least one of the racks of the second row. The method also includes forming an enclosure around an area between the first row and the second row, and drawing air from the area into one of the racks and passing the air out of a front face of the one of the racks.
[0007] The method can include a further step of cooling the air drawn into the one of the racks prior to passing the air out of the front face. The step of forming an enclosure may include coupling first and second side panels and a roof panel between the first row and the second row. At least one of the first side panel and the second side panel may include a door and the roof panel can include a translucent portion. Additionally, the method can include using an uninterruptible power supply to provide power to equipment in the racks.
[0008] Yet another aspect of the present invention is directed to a modular data center that includes a plurality of racks, each of the racks having a front face and a back face, wherein the plurality of racks is arranged in a first row and a second row, such that the back faces of the racks of the first row are facing the second row, and the back faces of the racks of the second row are facing the first row. The modular data center further includes means for enclosing a first area between the first row and the second row, and means for drawing air from the enclosed area, cooling the air, and returning cooled air to a second area.
[0009] The means for drawing air can further include means for passing cooled air through the front face of one of the racks. The modular data center can also be comprised of means for providing uninterruptible power to equipment in the racks. Access means for allowing access into the first area may also be a design feature of the modular data center.
[0010] The invention will be more fully understood after a review of the following figures, detailed description and claims.
BRIEF DESCRIPTION OF THE FIGURES
[0011] For a better understanding of the present invention, reference is made to the figures which are incorporated herein by reference and in which:
[0012] FIG. 1 is a perspective view of a modular data center cooling system for rack-mounted equipment in accordance with one embodiment of the invention;
[0013] FIG. 2 is a top view of another modular data system, similar to the system of FIG. 1 ; and
[0014] FIG. 3 is a block flow diagram of a process of cooling equipment mounted in modular data centers in one embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Embodiments of the invention provide a data center infrastructure having a cooling system for cooling rack-mounted electronic equipment. Embodiments of the invention provide a modular data center for rack-mounted equipment, wherein the modular data center provides power distribution, cooling and structural support for the rack-mounted equipment. The power distribution unit and cooling is provided in some embodiments using redundant systems to prevent downtime due to electrical or mechanical failures. As understood by those skilled in the art, other embodiments are within the scope of the invention, such as embodiments used to provide infrastructure for equipment other than electronic equipment.
[0016] A system for providing power distribution for rack-mounted equipment which can be used with embodiments of the present invention is described in U.S. patent application Ser. No. 10/038,106, entitled, “Adjustable Scalable Rack Power System and Method,” which is herein incorporated by reference.
[0017] Referring to FIG. 1 , a perspective view of a modular data center 10 is shown. The modular data center 10 includes a power distribution unit 14 , a power protection unit 12 , a floor mounted cooling unit 16 , equipment racks 18 , and a hot room 22 . The modular data center 10 also has a door 52 having a window 54 , a roof 56 , a cold water supply and return 60 , and a voltage feed 58 . The data center 10 is a modular unit comprised of the power distribution unit 14 , the power protection unit 12 the floor mounted cooling unit 16 , and equipment racks 18 positioned adjacent to each other to form a row 32 and a row 34 . Row 32 and row 34 are substantially parallel. The power distribution unit 14 and the power protection unit 12 can be located directly adjacent to one another, and can be located at the end of one of the rows. The floor-mounted cooling unit 16 may be located and positioned adjacent to the power distribution unit 14 . Remaining enclosures forming the at least one additional row in the data center 10 are equipment racks 18 . The hot room 22 is located between row 32 and row 34 , and rows 32 and 34 comprise two of the perimeter walls of the modular data center 10 .
[0018] The power distribution unit 14 typically contains a transformer, and power distribution circuitry, such as circuit breakers, for distributing power to each of the racks in the modular data center 10 . The power distribution unit 14 provides redundant power to the racks 18 and can monitor the total current draw. An uninterruptible power supply can provide uninterruptible power to the power distribution unit 14 . Preferably, the power distribution unit 14 includes a 40 kW uninterruptible power supply having N+1 redundancy, where the ability to add another power module provides N+1 redundancy. In one embodiment of the invention, input power to the power distribution unit 14 is received through the top of the rack from a voltage feed 58 . In one embodiment, the voltage feed 58 is a 240 volt feed coupled to the power distribution unit 14 that enters through the roof panel 56 . Alternatively, the input power may be received from underneath the rack, as through a raised floor, or through the back of the rack.
[0019] The power protection unit 12 provides redundant power protection for centralized information technology equipment, as is contained in the equipment racks 18 . The power protection unit 12 can have individual power modules and battery modules that can be individually added or removed to accommodate different load requirements. The use of multiple power modules and battery modules provides redundancy by allowing continued operation despite the failure of any one power module or battery module. For example, the power protection unit can include a Symmetra PX® scalable, uninterruptible power supply having a three-phase input and a three-phase output, available from American Power Conversion Corporation, of West Kingston, R.I., or the power protection unit can include one of the uninterruptible power supplies described in U.S. Pat. No. 5,982,652, titled, “Method and Apparatus for Providing Uninterruptible Power,” which is incorporated herein by reference.
[0020] The floor mounted cooling unit 16 provides heat removal by use of a chilled water supply, which enters the unit through supply line 60 . Alternatively, the cooling units can provide heat removal using DX compressorized cooling via use of a direct expansion refrigerant-based unit, which can be in the unit itself. The cooling unit contains a primary chilled water coil and secondary direct expansion coil within the same frame. The cooling unit can be configured for air, water or glycol use. Cooled air can be released through the bottom of the unit or the top of the unit. In one embodiment of the invention, cool air is released from the cooling unit 16 out its front face, so that the air flow is from the back of the rack and out the front of the rack. The cooling unit 16 can further be configured as one, two or three modules. In the embodiment shown in FIG. 1 , a three-module cooling unit is used.
[0021] In the embodiment of FIG. 1 , each of row 32 and row 34 is comprised of six racks. In embodiments of the invention, the number of racks and the function of the equipment in the racks can vary. In one embodiment of the invention, the racks 18 are modified standard 19 inch racks, such as those available from American Power Conversion Corporation of West Kingston, R.I., under the trade name NETSHELTER VX Enclosures®.
[0022] The back face of each of the power distribution unit 14 , the power protection unit 12 , the floor mounted cooling unit 16 , and the equipment racks 18 faces the interior of the modular data center 10 , or the hot room 22 . Essentially, the back faces of the racks in row 32 face the back faces of the racks in row 34 . In one embodiment, the equipment racks 18 have their rear doors removed so that each rack 18 remains open to the inside of the hot room 22 . In the embodiment shown, the modular data center 10 contains seven equipment racks 18 . Alternatively, in another embodiment, six equipment racks 18 complete the rows, but more than seven equipment racks 18 can complete the rows contained in the data center 10 and can be adjacent to one another or adjacent to other enclosures in the data center 10 , such as the power distribution unit 14 , the power protection unit 12 , or the floor mounted cooling unit 16 .
[0023] The door 52 located at the end of the row of racks is attached with hinges 53 to a detachable frame 55 . The detachable frame 55 is located behind the power protection unit 12 . The detachable frame may be positioned behind any one of the power protection unit 12 , the power distribution unit 14 , or the equipments racks 18 , depending on which of the units are positioned at the end of a row in the data center 10 . The detachable frame 55 allows the door 52 to be quickly removed for replacement of the power protection unit 12 if necessary. The hot room is accessible by thc door 52 and can be monitored through the observation window 54 . Preferably, a door 52 is located at each end of the hot room 22 . Generally, the door 52 is a 2×36 inch insulated, lockable steel door having an insulated observation window 54 .
[0024] The cold water supply and return 60 can enter the hot room through supply pipes into the roof 56 or directly into the roofs of the racks. The voltage feed 58 can also enter through the roof 56 or through the roofs of the racks. Alternatively, the cold water supply and return 60 and the voltage feed 58 enter the hot room through a raised floor on which the modular data center rests or from another location outside of the room and into the racks, such as into the sides of the racks.
[0025] The roof panel 56 is preferably a semi-transparent plexiglass roof panel supported by steel supports 62 that are positioned at intervals along the length 72 of the data center 10 . The roof 56 extends to cover the top of the hot room 22 located in the middle of the rows of racks. The roof 56 can be easily detachable to allow for removal of racks 18 or the power protection unit 12 when necessary. A roof panel 56 constructed of semi-transparent plexiglass allows room light to enter the space defining the hot room 22 . Additionally, the plexiglass roof 56 is preferably substantially airtight.
[0026] The hot room 22 is completely enclosed and has walls formed by the backside of the racks 18 and walls comprised of the door 52 attached at each end of the hot room 22 . Alternatively, panels without doors can be the walls that complete the hot room. The hot room 22 is a substantially airtight passageway when the roof panel 56 is in place. Thus, the modular data center 10 is an enclosed computer infrastructure defined on its outside perimeter by the front face of each of the racks 18 , power protection unit 12 , power distribution unit 14 , and cooling unit 16 , and having a hot room 22 in its midsection. The outside walls of the hot room formed by the doors 52 are a portion of two of the outside walls of the modular data center 10 .
[0027] Referring to FIG. 2 , a top view of a modular data center 10 in one embodiment of the invention is shown. The modular data center of FIG. 2 is similar to that of FIG. 1 , but has five racks in each of row 32 and row 34 , rather than the six racks in each row of FIG. 1 . With like numbers referring to like embodiments, the modular data center 10 of FIG. 2 is comprised of the power distribution unit 14 , the power protection unit 12 , the floor mounted cooling unit 16 , the equipment racks 18 , and the hot room 22 . The power protection unit 12 is positioned directly adjacent to one side of the power distribution unit 14 , while a floor-mounted cooling unit 16 is positioned on the other side of the power distribution unit. A service clearance area 20 surrounds the modular data center 10 . In FIG. 2 , an embodiment of the invention is shown having six equipment racks 18 and a cooling unit 16 having two modules.
[0028] The dimensions of the modular data center 10 depend on the number of racks included in each of the rows of racks. For example, and referring again to FIG. 1 , a data center 10 having six equipment racks 18 can have a width of 120″, indicated by arrow 28 , a length of 120″, indicated by arrow 29 , and a height of 36″, indicated by arrow 24 . The height 24 of the data center can be 36″, while the service clearance is preferably 36″ in width 26 . With the inclusion of the service clearance 20 , the floor surface area for the data center 10 is, preferably, a length 30 of 192″ and a width 30 of 192″. Alternatively, and referring to FIG. 2 , a data center 10 having seven equipment racks 18 can have a width of 120″ and a length of 144″, while the height of the data center 10 is 36″. With the inclusion of the service clearance 20 , the floor surface area for an alternate data center is 192″ by 216″. The dimensions of the modular data center are given only as examples, but can vary significantly depending upon the type and size of racks used to design the data center.
[0029] The modular data center 10 is operational when provided with a source of chilled water 60 and a voltage feed 58 . The data center can include a number of different power input designs, but is preferably a 40 kW design, allowing 6.7 kW/rack in a system having six equipment racks 18 , or 5.7 kW/rack in a system having seven equipment racks 18 , for example. Cold water enters the floor mounted cooling units 16 via supply lines 60 . A common supply line 60 can provide cold water to one or more cooling units simultaneously, as the cooling units 16 are connected to the common supply 60 with flexible hose that is easily disconnected.
[0030] The modular data center 10 provides cooling for equipment in the data center as follows. Air from the room, or ambient air, filters through the front of the racks 18 to cool the equipment stored in the racks 18 . Air enters through the front of the racks 18 and is expelled out of the backside of the racks 18 . As the air passes through the equipment racks 18 , the temperature of the air rises. The respectively warmer air is expelled into the hot room 22 . The hot room 22 contains the warm air and prevents the warm air from mixing with air in the surrounding room. The cooling unit 16 draws warm air from the hot room and return cool air to the room outside the data center 10 . The warm air enters the cooling units 16 directly from the hot room 22 . The cold water supply 60 acts within the cooling unit to lower the temperature of the air, and the cooled air is then released into the surrounding area. The air is recycled to the surrounding room at a substantially cooled temperature. For example, the cooling unit 16 generally receives air from the hot room at 95° F. and cools it to a temperature of approximately 72° F. before it is released into the area surrounding the data center 10 . The floor mounted cooling unit 16 operates at substantially higher supply and return temperatures, allowing realization of high capacity without latent heat removal.
[0031] Referring to FIG. 3 , with further reference to FIGS. 1-2 , the data center 10 is configured to perform a process of cooling equipment stored in enclosed racks using an infrastructure having independent power and coolant supplies. The process 100 includes the stages shown, although the process 100 may be altered, e.g., by having stages added, deleted, or moved relative to the stages shown.
[0032] The process 100 of FIG. 3 includes stage 102 , wherein power is supplied from a power distribution unit to a plurality of equipment racks 18 . The equipment racks 18 may contain a variety of electronic equipment that requires a consistent power supply to avoid system downtime. A voltage feed 58 is connected to the power distribution unit 14 , and a power protection unit 12 is installed adjacent to the power distribution unit 14 to ensure redundant power supply.
[0033] At stage 104 , the racks 18 draw cool air from the surrounding room through the front face of the racks 18 . There may, for example, be an air distribution unit within the racks and/or within equipment contained in the racks that draws the room air into the rack 18 and distributes the air throughout the rack to cool components contained in the rack. As the air passes through the rack 18 , the air increases in temperature.
[0034] At stage 106 , the racks 18 expel the air at an increased temperature into the hot room 22 . The air is expelled out of the backside of the racks 18 . As described above, in one embodiment, the racks 18 do not have rear doors. In other embodiments, rear doors may be included on the racks with the warm air being expelled into the hot room through vents in the doors. Air is held in the hot room 22 at an increased temperature and mixing of the warm air with the surrounding ambient air is prevented.
[0035] At stage 108 , the cooling unit draws the warm air from the hot room 22 . The cooling unit 16 uses the cold water from the cold water supply 60 to cool the air from the hot room. At stage 110 , the cooled air is released from the cooling unit into the surrounding room, which completes the cooling cycle. The air in the surrounding room is then drawn into the racks 18 once again, and the cycle continues.
[0036] Other embodiments are within the scope and spirit of the appended claims. For example, air could be forced up through the equipment racks 18 . Air moved through the racks 18 could be of varying temperatures, including hot air. The data center 10 may be configured to distribute gases other than air. Additionally, a refrigerant or other coolant may be used rather than cold water. Further, a controller can be coupled to the data center 10 to monitor air temperatures and flow rates, as well as power supply so that each rack is provided adequate power consistently. A data center may contain a single equipment rack 18 having a single cooling unit 16 creating an individual data center, whereby power is distributed to a single data center 10 or multiple single-rack data centers simultaneously.
[0037] Further, in embodiments of the present invention, the roof over the hot area may include a number of fans that are controlled to exhaust air from the hot area in the event of a failure of an air conditioning unit in the modular data center, and/or when air temperature in the hot area exceeds a predetermined limit.
[0038] Having thus described at least one illustrative embodiment of the invention, various alterations, modifications and improvements will readily occur to those skilled in the art. Such alterations, modifications and improvements are intended to be within the scope and spirit of the invention. Accordingly, the foregoing description is by way of example only and is not intended as limiting. The invention's limit is defined only in the following claims and the equivalents thereto. | A modular data center includes a plurality of racks, each of the racks having a front face and a back face, wherein the plurality of racks is arranged in a first row and a second row, such that the back faces of racks of the first row are facing the second row, and the back faces of the racks of the second row are facing the first row, a first end panel coupled between a first rack of the first row and a first rack of the second row, the first end panel having a bottom edge and a tope edge, a second end panel coupled between a second rack of the first row and a second rack of the second row, the second end panel having a top edge and a bottom edge, and a roof panel coupled between the top edge of the first panel and the top edge of the second panel. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to ZnO films, methods for manufacturing the ZnO films, and luminescent elements. In particular, the present invention relates to a p-type ZnO film, a method for manufacturing the ZnO film, and a luminescent element including the ZnO film.
[0003] 2. Description of the Related Art
[0004] Deposition of a ZnO film on a substrate has been studied for blue light-emitting diodes, solar cells, and the like. ZnO generally exhibits n-type conductivity as a result of adding a dopant such as Al. In order to form the pn junction, a p-type ZnO film is also necessary. However, it is difficult to form a p-type ZnO film.
[0005] A method for forming a p-type ZnO film is disclosed in a literature entitled “p-Type Electrical Conduction in ZnO Thin Films by Ga and N Co doping” (Japan J. Appl. Phys., Vol. 38 (1999) pp. L1205-L1207). In this method, a ZnO film is deposited on a glass substrate using a ZnO target doped with Ga while the inside of the vacuum chamber employed is maintained under an atmosphere of nitrogen gas, and the film is exposed to an excimer laser beam to form a p-type ZnO film by laser ablation.
[0006] However, a laser beam having a small spot size is used in the laser ablation process. Therefore, when a film is deposited on a substrate having a large diameter, the scanning length and the scanning time of the laser beam become very large. Accordingly, it takes a long time to cover the substrate with the film and the cost increases. Therefore it is difficult to put this method into practical use.
SUMMARY OF THE INVENTION
[0007] Accordingly, one object of the present invention is to provide a ZnO film having p-type conductivity and which can be easily formed on a large substrate, to provide a method for manufacturing the ZnO film, and to provide a luminescent element having the p-type ZnO film.
[0008] In order to overcome the problems described above, the present invention provides a ZnO film comprising ZnO as main material doped with a Group III element and a Group V element according to one preferred embodiment of the present invention. By doping with a Group III element and a Group V element to the film which mainly containing ZnO, a p-type ZnO film can be formed without performing laser ablation. Specifically, the p-type ZnO film of the present invention can be formed on a substrate by sputtering, ECR sputtering, CVD, MOCVD or MBE, and therefore, it can be formed at a speed higher speed than that of laser ablation and at low cost. Thus, the industrial productivity of p-type ZnO films can be increased.
[0009] The Group III element may be selected from the group consisting of Sc, Y, La, Ac, B, Al, Ga, In, Tl, lanthanides and actinides, and the Group V element may be selected from the group consisting of N, V, Nb, Ta, P, As, Sb and Bi. Preferably, the content of the Group III element is in the range of about 0.5% to 8% by weight and the content of the Group V element is in the range of about 1% to 16% by weight. Preferably, the content of the Group V element is higher than the content of the Group III element.
[0010] According to a methodological aspect, the present invention provides a method for manufacturing a ZnO film. The method includes the steps of: doping a material mainly containing Zn or ZnO with a Group III element and a Group V element to form a target; and depositing a ZnO film on a substrate using the target. The present invention is also directed to another method for manufacturing a ZnO film which method includes the steps of: doping a material mainly containing Zn or ZnO with a Group III element to form a target; depositing a ZnO film on a substrate using the target; and implanting Group V ions into the ZnO film. The Group III element and the Group V element may be contained in compounds, and specifically in oxides.
[0011] According to another preferred embodiment of the present invention, the present invention provides a ZnO film doped with a Group I element and a Group VII element and the film mainly contains ZnO. Preferably, the content of the Group I element is in the range of about 0.5% to 8% by weight and the content of the Group VII element is in the range of about 1% to 16% by weight. More, preferably, the content of the Group I element is about 0.5% to 7.5% and the content of the Group VII element is about 1 to 15%. Preferably, the content of the Group I element is higher than the content of the Group VII element. By doping a film mainly containing ZnO with a Group I element and a Group VII element such that the content of the Group I element is higher than that of the Group VII element, a p-type ZnO film can be formed without performing laser ablation. Specifically, the p-type ZnO film of the present invention can be formed on a substrate by sputtering, ECR sputtering, CVD, MOCVD or MBE, and therefore, it can be formed at a speed higher speed than that of laser ablation and at low cost. Thus, the industrial productivity of p-type ZnO films can be increased.
[0012] The ZnO film can be applied to luminescent elements, such as blue light-emitting diodes. By using the p-type ZnO film of the present invention to increase the manufacturing speed of the luminescent elements, mass productivity can be increased.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 is a schematic illustration of a system for investigating the capacitance-voltage characteristics of a ZnO film;
[0014] [0014]FIG. 2 is a graph showing the capacitor-voltage characteristics of a ZnO film doped with Y and N;
[0015] [0015]FIG. 3 is a graph showing the capacitor-voltage characteristics of a ZnO film doped with Al; and
[0016] [0016]FIG. 4 is a sectional view of a luminescent element according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The ZnO Film
FIRST EXAMPLE
[0017] First, Zn, which is a constituent of a metal target, was doped with 1 to 6% by weight of Y 2 O 3 to form Zn metal target. Each Zn metal target was put into a target holder in a sputtering apparatus and a sapphire substrate was placed in the sputtering apparatus. Next, a ZnO film was deposited to a thickness of 1 μm on the sapphire substrate by RF magnetron sputtering under the following conditions.
[0018] Gas: mixture of Ar and N 2 gases
[0019] Gas flow ratio: Ar:O 2 :N 2 =25:10:5
[0020] Gas pressure: 1×10 −2 Torr
[0021] Substrate temperature: 200° C.
[0022] Thus, a p-type ZnO film doped with the Group III element Y and the Group V element N was formed on the sapphire substrate. In particular, a Zn metal target doped with 4% by weight of Y 2 O 3 resulted in an excellent ZnO film.
[0023] The conductivity type of ZnO films was determined through investigating the capacitance-voltage characteristics (hereinafter referred to as CV characteristics). As shown in FIG. 1, the CV characteristics were obtained by measuring the voltage Vgs and capacitance Ch between a circular electrode 2 and a C-shaped electrode 3 which were formed on the surface of a measured object (ZnO film) 1 . When the measured object 1 has p-type conductivity, the capacitance-voltage curve slopes down to the right where the horizontal axis and the vertical axis represent the voltage Vgs and the capacitance Ch between the electrodes, respectively; when it has n-type conductivity, the curve slopes up to the right. By obtaining the CV characteristics, the conductivity type of measured objects 1 can be determined.
[0024] Zn, which is a constituent of a metal target, was doped with 1 to 6% by weight of the Group III (Sc, Y, La, Al, Ga and the like) to form Zn or ZnO target. And ZnO film is formed on the substrate using the Zn metal terget or ZnO ceramic target. ZnO film is doped with the content of the Group III in the range of about 0.5% to 8% by weight.
[0025] [0025]FIG. 2 shows the CV characteristics of a measured object (the ZnO film doped with Y and N) according to the first example. The horizontal axis and the vertical axis of the graph represent the voltage Vgs between the electrodes and the capacitance Ch, respectively. As shown in FIG. 2, the capacitance-voltage curve of the ZnO film slopes down to the right and, therefore, the ZnO film is determined as p-type. By contrast, a ZnO film doped with Al exhibits a capacitance-voltage curve sloping up to the right, as shown in FIG. 3, and is, therefore, determined as n-type.
SECOND EXAMPLE
[0026] First, Zn, which is a constituent of a metal target, was doped with 1% by weight of Ga and 2% by weight of Bi to form a Zn metal target. The Zn metal target was put into a target holder in a sputtering apparatus and a sapphire substrate was placed in the sputtering apparatus. Next, a ZnO film was deposited to a thickness of 1 μm on the sapphire substrate by RF magnetron sputtering under the following conditions.
[0027] Gas: mixture of Ar and O 2 gases
[0028] Gas flow ratio: Ar:O 2 =50:50
[0029] Gas pressure: 1×10 −2 Torr
[0030] Substrate temperature: 200° C.
[0031] Thus, a p-type ZnO film doped with the Group III element Ga and the Group V element Bi was formed on the sapphire substrate. The ZnO film had a specific resistance of 0.1·cm or less.
[0032] As in the same manner, ZnO films doped with various amounts of Ga and Bi were formed. As a result, Zn metal target or ZnO ceramic target doped with 1% to 10% by weight of Ga and 2% to 20% by weight of Bi (wherein, Ga content>Bi content) resulted in excellent p-type ZnO films.
[0033] Also, Zn metal target or ZnO ceramic target doped with other combinations of a Group III element and a Group V element, such as Al and Nb, resulted in p-type ZnO films.
[0034] Zn, which is a constituent of a metal target, was doped with 1 to 6% by weight of the Group III (Sc, Y, La Al, Ga and the like) and 1 to 20% by weight of the Group V (N, V, Nb, P, As and the like) to form Zn metal target or ZnO ceramic target. And ZnO film is formed on the substrate using the Zn metal target or ZnO ceramic target. ZnO film is doped with the content of the Group III in the range of about 0.5% to 8% by weight and the content of the Group V in the range of about 1% to 16% by weight.
THIRD EXAMPLE
[0035] A metal target doped with a Group III element may be used to deposit a ZnO film, and the ZnO film is subsequently doped with Group V ions by implantation. For example, Zn was doped with Ga to form a Zn metal target. A ZnO film was deposited using the Zn metal target on a sapphire substrate by RF magnetron sputtering. Then, the ZnO film was doped with As ions at about 1015 cm −2 by implantation and, thus, a p-type ZnO film was formed.
[0036] The above-described ZnO films were formed by sputtering (RF magnetron sputtering), but they may be formed by molecular beam epitaxy (MBE), metal-organic chemical vapor deposition (MOCVD) or chemical vapor deposition (CVD).
FOURTH EXAMPLE
[0037] When a ZnO film was doped with at least one element selected from the group consisting of Li, Na, K, Rb, Cu, Ag and Au, which belong to Group I, and at least one element selected from the group consisting of Mn, Tc, Re, F, Cl, Br, I and At, which belong to Group VII, the resulting ZnO film also exhibited p-type conductivity. Specifically, Zn, which is a constituent of a metal target, was doped with 2% by weight of Cu and 1% by weight of Mn to form a Zn metal target. The Zn metal target was put into a target holder in a sputtering apparatus and a sapphire substrate was placed in the sputtering apparatus. Next, a ZnO film was deposited to a thickness of 1 μm on the sapphire substrate by RF magnetron sputtering under the following conditions.
[0038] Gas: mixture of Ar and O 2 gases
[0039] Gas flow ratio: Ar:O 2 =50:50
[0040] Gas pressure: 1×10 −2 Torr
[0041] Substrate temperature: 200° C.
[0042] Thus, a p-type ZnO film doped with the Group I element Cu and the Group VII element Mn was formed on the sapphire substrate. Preferably, the content of the Group I element is more higher than that of the Group VII element.
[0043] When a Group I element and a Group VII element are used as dopants, a Zn metal target or ZnO ceramic target doped with a Group I metal or molecule may also be used to form a ZnO film and, then, Group VII ions are implanted into the ZnO film. For example, Zn was doped with Cu to form a Zn metal target or ZnO ceramic target. A ZnO film was deposited on a sapphire substrate using the Zn metal target by RF magnetron sputtering. Then, the ZnO film was doped with Br ions at about 1016 cm −2 by implantation and, thus, a p-type ZnO film was formed.
[0044] Usually, amounts of the dopants in the ZnO film are smaller than that of the dopants in the target, between half and 90% of the amounts of the dopants in the metal target.
The Luminescent Element
[0045] [0045]FIG. 4 is a sectional view of a luminescent element 11 of the present invention. The luminescent element 11 has a c-plane sapphire substrate 12 . A metallic layer 13 and a p-type ZnO film (thin film) 14 are deposited, in that order, on the c-plane sapphire substrate 12 . The ZnO film 14 is doped with a group III metal and a Group V metal in accordance with the method of the present invention and, thus, exhibits p-type conductivity. The luminescent element 11 also has an n-type ZnO film (thin film) 15 doped with Al on the p-type ZnO film 14 . An upper electrode 16 and a lower electrode 17 are disposed on the upper surface of the n-type ZnO film 15 and the upper surface of the metallic layer 13 , respectively.
[0046] When a voltage is applied between the upper electrode 16 and the lower electrode 17 , light emitted between the p-type ZnO film 14 and the n-type ZnO film 15 travels to the outside through the n-type ZnO film 15 .
[0047] While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing the scope and spirit of the invention. The scope of the invention, therefore, is to be determined solely by the following claims. | A p-type ZnO film is formed on a sapphire substrate by RF magnetron sputtering in an atmosphere of a mixture of Ar and N 2 gases, using a Zn metal target doped with Y 2 O 3 . The p-type ZnO film can be easily formed even on a large-sized substrate. | 2 |
This application is a continuation-in-part application of pending application Ser. No. 12/060,507, filed on Apr. 1, 2008, entitled REAL TIME DOSER EFFICIENCY MONITORING, the entire contents of which are incorporated herein by reference.
FIELD
This disclosure relates to an exhaust gas aftertreatment system and a doser system used with the aftertreatment system to inject a dosing agent into exhaust gas in the aftertreatment system.
BACKGROUND
The use of an aftertreatment system to treat exhaust gas before the exhaust gas is exhausted to atmosphere is known. One known aftertreatment system uses a diesel oxidation catalyst (DOC) device that is intended to react with the exhaust gas to convert nitric oxide to nitrogen dioxide. In the case of diesel exhaust, a diesel particulate filter (DPF) can also be provided downstream of the DOC to physically remove soot or particulate matter from the exhaust flow.
When exhaust gas temperatures are sufficiently high, soot is continually removed from the DPF by oxidation of the soot. When the exhaust gas temperature is not sufficiently high, active regeneration is used. In the case of diesel engine exhaust, one form of active regeneration occurs by injecting fuel into the exhaust gas upstream of the DOC. The resulting chemical reaction between the fuel and the DOC raises the exhaust gas temperature high enough to oxidize the soot in the DPF.
A doser system that includes a doser injector is used to inject the fuel into the exhaust gas. Deterioration of the doser injector can occur over its lifetime, for example due to doser tip carboning or a reduction of doser stroke. Doser deterioration is believed to be one of the most frequent modes of failure in aftertreatment systems. A known doser monitoring method that attempts to determine the efficiency of the doser injector senses the temperature difference across the DOC. However, the effectiveness of this method is decreased by deterioration of the DOC which cannot be independently monitored.
SUMMARY
Improved real time doser efficiency monitoring methods are described that can be used to monitor the efficiency of doser systems. The disclosed methods can be implemented in a number of areas. For example, in a diesel truck application, the doser efficiency can be monitored all the time, no matter whether the truck is in a transient or steady state.
In one disclosed embodiment, which will be referred to herein as the average pressure difference method, the efficiency of a doser injector that is configured and arranged to inject a fluid, such as a dosing agent, into exhaust gas is monitored by determining an average pressure of the fluid when the doser injector is not injecting, and determining an average pressure of the fluid when the doser injector is injecting at a predetermined commanded injection rate. The difference between the average pressure when the doser injector is not injecting and the average pressure when the doser injector is injecting is then determined. Thereafter, the determined pressure difference is compared against a predetermined expected pressure difference. The average pressure when injecting can be determined at a suitable dosing frequency, for example 10 Hz.
The fluid that is injected can be a suitable dosing agent including, but not limited to, hydrocarbon fuels such as diesel fuel, alcohols, urea, ammonia, natural gas, and other agents suitable for use in aftertreatment of exhaust gases. However, the inventive concepts of the average pressure difference method are not limited to these types of dosing agents. The average pressure difference method is also useful when air is the injected working fluid.
In another disclosed embodiment, which will be referred to herein as the average instant pressure difference method, a doser efficiency monitoring method is described that determines the average instant pressure difference, defined as the average pressure while the doser is off minus the average pressure while the doser is on, within one duty cycle of the doser injector. In this method, the efficiency can be monitored by determining the average instant pressure difference of the dosing agent across an orifice, such as within a shut-off valve assembly, within a duty cycle of the doser injector. The doser injector is preferably pulse-width modulation controlled.
The average instant pressure difference is the maximum pressure drop so it has a better signal-to-noise ratio compared to the average pressure difference method, and is independent of the dosing command. The average instant pressure difference method is also more accurate, for example within 5% error.
The real time doser efficiency monitoring methods can be implemented by a doser system that comprises a doser injector that is configured and arranged to inject a dosing agent into exhaust gas, a dosing agent supply line connected to the doser injector, and a dosing agent shut-off valve assembly connected to the supply line that is configured and arranged to control the flow of the dosing agent in the supply line and to the doser injector. The valve assembly includes a pressure sensor for detecting dosing agent pressure in the valve assembly. A controller can be used to monitor the efficiency of the doser injector.
The disclosed methods can complete monitoring within fraction of seconds, which works well even during transient engine operations and dosing. The disclosed methods also have increased accuracy compared to prior methods. The disclosed methods are also independent of the performance, e.g. degradation, of individual aftertreatment components as is the current temperature based efficiency monitoring method.
The disclosed methods permit compliance with the on-board diagnostics requirement for the year 2010, which requires independent monitoring for each aftertreatment component. In addition, the higher efficiency achieved by the disclosed methods reduces the injection of excess fuel, called hydrocarbon slip, thereby avoiding violation of hydrocarbon emission regulations. Further, the occurrence of false detected “bad” dosers is reduced, thereby reducing warranty costs of doser replacement.
DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an exemplary doser system that can implement the real time doser efficiency monitoring methods described herein.
FIG. 2 illustrates the shut-off valve assembly of the system in FIG. 1 .
FIG. 3 is a detailed view of the portion in box 3 of FIG. 2 illustrating the trim orifice in the shut-off valve assembly.
FIG. 4 depicts a pressure reading for use with the average instant pressure difference method over one cycle period of the doser injector.
FIG. 5 is a graph of the dosing agent pressure versus time at different dosing rates for use with the average instant pressure difference method.
FIG. 6 is a graph of the doser efficiency versus instant pressure difference for 6 doser injectors with differing deterioration levels for use with the average instant pressure difference method.
FIG. 7 is a graph of dosing agent pressure and dosing rate versus time.
FIG. 8 depicts the average instant pressure difference method over one cycle period of the doser injector.
FIGS. 9A-C are graphs relating to the average pressure difference method of monitoring doser efficiency.
FIG. 10 depicts the average pressure difference method.
FIG. 11 is a graph of expected pressure drop versus dosing rate for use with the average pressure difference method encompassed in FIGS. 9A-C .
DETAILED DESCRIPTION
With reference to FIG. 1 , a doser system 10 for an exhaust gas aftertreatment system is illustrated. For sake of convenience in describing the unique concepts, this description will describe the doser system 10 as being a hydrocarbon doser system for a diesel fuel engine that injects diesel fuel into exhaust gas from the engine. However, it is to be realized that the unique concepts described herein can be applied to other doser systems that inject other types of dosing agents.
The basic configuration and operation of the doser system 10 and aftertreatment system are well known to persons of ordinary skill in the art. The doser system 10 includes a doser injector 12 that is connected to an exhaust gas connection tube 14 connected to the exhaust from an engine (not illustrated). As part of the aftertreatment system, exhaust gases in the connection tube 14 flow to a diesel oxidation catalyst (DOC) device that is intended to react with the exhaust gas to convert nitric oxide to nitrogen dioxide. A diesel particulate filter (DPF) is provided downstream of the DOC to remove soot or particulate matter from the exhaust flow.
The doser injector 12 is configured and arranged to inject a dosing agent, which in this exemplary embodiment is diesel fuel, into the exhaust gas in the tube 14 to increase the temperature of the DOC. The fuel is supplied via a fuel supply line 16 . A shut-off valve assembly 18 is connected to the supply line 16 and is configured and arranged to control the flow of fuel in the supply line 16 and to the doser injector 12 .
Details of the shut-off valve assembly 18 are illustrated in FIGS. 2 and 3 . The assembly 18 includes a fuel inlet port 20 , a fuel outlet port 22 connected to the supply line 16 , and a drain port 24 . A pressure sensor 26 connected to the valve assembly 18 senses fuel pressure in the assembly 18 . A trim orifice 28 is provided to keep the fuel pressure in the assembly 18 more stable. The construction and operation of the valve assembly 18 illustrated in FIGS. 2 and 3 are conventional.
Returning to FIG. 1 , a controller 30 is connected to the pressure sensor 26 and receives pressure readings therefrom. The controller 30 monitors the efficiency of the doser injector 12 by, in one embodiment, determining the average instant pressure difference of the fuel at the shut-off valve assembly 18 within one duty cycle of the doser injector which is pulse-width modulation (PWM) controlled. The controller 30 , which can be an electronic control module (ECM), can also control the aftertreatment system. The doser injector 12 is controlled by a separate PWM controller 32 .
The average instant pressure difference method for monitoring doser efficiency will now be described with respect to FIGS. 4-7 , together with FIGS. 1-3 . The fuel dosing rate is controlled by the duty cycle of the PWM controller. FIG. 4 shows one cycle period T of doser pressure, with P off and P on being the fuel pressure measured by the pressure sensor 26 when the doser injector is turned off and on, respectively. All references to pressure herein and the pressures shown in FIGS. 5-7 are the fuel pressure measured by the pressure sensor 26 in the valve assembly 18 . P avg is the average pressure when the doser injects fuel at that duty cycle, calculated as follows:
P
avg
=
P
on
·
T
on
+
P
off
·
(
T
-
T
on
)
T
=
P
on
·
R
D
C
+
P
off
·
(
1
-
R
D
C
)
(
Eq
.
1
)
where
R
D
C
=
T
on
T
Ratio of duty cycle
The average pressure difference, ΔP avg , can be calculated as follows:
Δ
P
avg
=
P
off
-
P
avg
=
P
off
-
P
on
·
R
D
C
-
P
off
·
(
1
-
R
D
C
)
=
(
P
off
-
P
on
)
·
R
D
C
=
Δ
P
ins
·
R
D
C
(
Eq
.
2
)
The average instant pressure difference, ΔP ins , is the average pressure difference by a factor of duty cycle. The average instant pressure difference is substantially independent of dosing rate. This is evident from FIG. 5 which depicts a graph of dosing agent pressure versus time at different dosing rates. From FIG. 5 , it can be seen that the pressure difference (i.e. the difference between the maximum pressure P off and the minimum pressure P on ) remains substantially constant even with dosing rate changes.
FIG. 6 is a graph of the doser efficiency versus average instant pressure difference for 6 doser injectors with differing deterioration levels. From this graph, it can be determined that under the conditions set forth (e.g. at a supply pressure of about 1200 kPa) in the graph, a 10 kPa variation in instant pressure difference means approximately a 3.1% doser efficiency error.
FIG. 7 is a graph depicting various pressure measurements when the fuel dose rate changes from about 1.4 g/s to about 0.8 g/s within 2.2 seconds at a supply pressure of about 1950 kPa. The graph plots the individual instant pressure readings 40 versus time, the average pressure 42 versus time, the average instant pressure 44 versus time, and the dose rate 46 versus time.
FIG. 8 depicts the average instant pressure difference method, where the average pressure while the doser is off and the average pressure while the doser is on over one duty cycle are illustrated. T 1 is the initial delay time to avoid signal overshoot, while T 2 is the buffer time to avoid falling edge data.
In the average instant pressure difference method described herein, relying upon the average instant pressure difference within a single duty cycle eliminates duty cycle error. In addition, the average instant pressure difference method relies upon a relatively large range of instant pressure difference, shown in FIG. 7 as about 256 kPa, over the single duty cycle. This helps to minimize the impact of pressure variations on the doser efficiency. From FIG. 7 , the average instant pressure 44 while the doser is off holds relatively steady at about 1950 kPa, which is the assumed supply pressure. The variation in instant pressure difference while the doser injector is on varies by about 10 kPa. Assuming that the doser used in FIG. 7 is a 100% efficient doser, and assuming that a 100% efficiency doser at 1950 kPa supply pressure has an instant pressure difference of 256 kPa, then the doser efficiency error can be determined by taking the variation in instant pressure difference, 10 kPa, and dividing it by the pressure difference range of 256 kPa. The doser efficiency error for the average instant pressure difference method is thus about 3.9%.
The average pressure difference method of monitoring doser efficiency is illustrated in FIGS. 9A-C , 10 and 11 , along with FIG. 7 . This method compares the actual pressure drop with an expected pressure drop at a predetermined dosing command date. The pressure drop is the difference between the average pressure when the doser injector is not injecting and the average pressure when the doser injector is injecting at the predetermined commanded dosing rate.
With reference to FIGS. 9A-C , the supply pressure, dosing frequency and dosing rate, respectively, are plotted against time. Pressure drop is defined as the difference between the average pressure when the doser is not dosing or injecting, for example at point 1, and the average pressure when the doser is dosing or injecting at a predetermined commanded dosing rate, for example point 2. This is represented by the following equation:
Δ P=P 1 −P 2 (Eq. 3)
@D max maximum dosing rate
The pressure readings can be taken at any location(s) one finds suitable for obtaining accurate pressure readings. For example, the pressure while the doser is not dosing and the dosing rate equals zero can be measured upstream of the valve assembly 18 in FIG. 1 in a fuel filter manifold, while the pressure when the doser is dosing at a predetermined commanded dosing rate can be measured at the valve assembly 18 with the pressure sensor 26 . The average pressure when the doser is dosing is then calculated based on the dosing frequency. The pressure drop is preferably determined at the highest dosing rate, which provides the highest resolution and thus better accuracy.
In the example illustrated in FIGS. 9A-C , P 1 is about 1260 kPa and P 2 is about 1125 kPa, so that ΔP is about 135 kPa at a commanded dosing rate of 3.5 g/sec and a dosing frequency of 2.5 Hz.
FIG. 10 depicts the average pressure difference method, where the average pressure while the doser is not dosing and the average pressure while the pressure is dosing at the predetermined dosing rate are shown.
FIG. 11 is a graph that plots expected fuel pressure drop versus actual dosing rate. It has been found that the pressure drop versus dosing rate variability decreases as dosing frequency increases. Therefore, the graph in FIG. 11 is taken at a dosing frequency of, for example, 10 Hz. In this graph, a pressure drop calibration curve is depicted which represents the average readings of a number of different dosers.
An exemplary implementation of the pressure drop method will now be described with respect to FIG. 11 . In this example, assume that the commanded dosing rate is 2.5 g/sec and assume that at this commanded dosing rate the calculated pressure drop determined using equation 3 is determined to be about 60 kPa. However, based on the pressure drop calibration curve, the expected pressure drop should have been about 98 kPa. Based on the determined pressure drop of about 60 kPa, the actual dosing rate is about 1.5 g/sec. Based on these readings, the deterioration percentage of the doser can be calculated as follows:
Deterioration
[
%
]
=
100
·
(
1
-
2.5
-
1.5
1.5
)
=
33
The results of the deterioration percentage calculation can be used in a number of ways. For example, if the percentage is high enough, a suitable message can be provided, such as lighting a warning lamp or providing a message on a visual display device, to notify a user of deterioration of the doser for monitoring purposes or possible replacement of the doser. Alternatively, the doser control can be adjusted by the deterioration amount to account for the deterioration so that the correct dosing rate is achieved.
In the average pressure difference method, the dynamic range of the average pressure difference is the dynamic range of the average pressure difference multiplied by a factor of duty cycle. Compare this with the average instant pressure difference method which relies upon the average instant pressure difference within a single duty cycle.
Although the monitoring methods herein have been described with respect to diesel fuel as the dosing agent, the concepts described herein can be applied to other dosing agents. For example, the dosing agent can be one or more of other types of fuels including hydrocarbon fuels, or other dosing agents such as alcohols, urea, ammonia, and natural gas. In addition, the concepts of the average pressure difference method can be applied when air is the working fluid, where the air is injected by the doser injector into the exhaust gas stream such as when air is used to clear the doser injector of residual dosing agent. Therefore, the terms “dosing”, “doser” and the like are intended to encompass injection of dosing agents as well as injection of air.
The monitoring methods described herein can be implemented in a number of different ways. For example, the monitoring methods can be implemented by software residing in an aftertreatment system controller, for example in the controller 30 . Alternatively, the disclosed monitoring methods can be implemented by hardware such as electronic circuitry at or near the pressure sensor 26 .
The concepts described herein may be embodied in other forms without departing from its spirit or characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. | A real time, average pressure difference method for monitoring doser efficiency is described that determines the difference between the average pressure when the doser is not injecting and the average pressure when the doser is injecting at a predetermined commanded injection rate. The average pressure difference method results in improved doser efficiency monitoring. The method can be implemented in a number of areas. For example, in a diesel truck application, the doser efficiency can be monitored accurately in real time. | 5 |
This is a division of application Ser. No. 295,448, filed Oct. 6, 1972, now U.S. Pat. No. 3,851,528.
BACKGROUND OF THE INVENTION
The present invention relates to an electronic circuit for maintaining constant current flow through an electrical component while simultaneously amplifying voltage changes developed across such electrical component and, more particularly, to such a circuit that is especially useful for maintaining constant current flow in a temperature probe of an electronic thermometer while simultaneously amplifying the voltage changes developed across such temperature probe due to changes in its temperature.
Electronic thermometers which rely on electrical transducers to register temperature changes have been devised. However, for various reasons none of such electronic thermometers available to date have been able to successfully compete with the common mercury-in-glass thermometer. For one thing, the temperature transducer or probe of most available electronic thermometers leaves much to be desired.
SUMMARY OF THE INVENTION
The present invention provides an electronic circuit which is especially useful in an electronic thermometer. In its most basic aspects, the thermometer includes as its temperature probe, a component having an electrical characteristic, such as its resistance to current flow, which is dependent in a predetermined manner on the temperature of such material.
The circuitry included as part of the thermometer for registering variations in the electrical characteristic of the component and translating such variations to temperature readings is especially designed to require low power and yet maintain accurate readings at all times. In this connection, the circuit utilizes low-powered operational amplifiers in providing its various functions. As a particularly important aspect of such circuit, it combines certain passive components with a single operational amplifier in such a manner that the amplifier is useable not only to amplify voltage changes representative of changes in the electrical characteristic of the semiconductive material, but also to provide a constant current flow through such semiconductive material. This use of one amplifier to perform two important functions of the circuit considerably reduces the overall power consumed and required by the thermometer.
The preferred circuit includes other features which are important in making an electronic thermometer commercially practical. For example, it is battery powered and includes an automatic battery cut-off portion which assures that no inaccurate readings are obtained at any time due to low battery power. In this connection, it should be noted that because of the low power requirements of the circuit, it can be run on two small (hearing aid size) 2.8 volt batteries, which batteries will provide it with the capability of making at least 15,000 temperature readings (30 seconds each) before the batteries need be changed.
As will be described or will become apparent from the following description of a preferred embodiment, the electronic circuit of the invention includes many other features which are important in the combination.
BRIEF DESCRIPTION OF THE DRAWINGS
With reference to the accompanying two sheets of drawings:
FIG. 1 is an enlarged, perspective view of an electronic thermometer incorporating the circuit of the invention; and
FIG. 2 is a simplified electrical schematic diagram of the thermometer of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference first to FIG. 1, a preferred electronic thermometer incorporating the circuit of the invention is generally referred to by the reference numeral 11. The showing in FIG. 1 is somewhat enlarged--the instrument is actually sized to easily fit within the shirt pocket of a nurse or the like who is apt to have continual use for the same. The thermometer 11 includes a casing 12 having an indicator 13 mounted on it for visually displaying temperature readings. Such indicator 13 is in the form of a temperature scale 14 having markings covering the range of between, for example, 95° and 105° F, and a moveable needle indicator 16 for alignment with specific temperature indicia on the scale 14. The electronic thermometer 11 is completely self contained. That is, the casing 12 encloses the circuitry for controlling the needle 16 and also the batteries for powering such circuit and the temperature probe of the thermometer. In this connection, a probe cord 17 is connected to the circuitry within the casing via a disconnectable plug 18. As is illustrated, the cord 17 is flexibly coiled so that when the thermometer is not in use, the cord is compact for ease in handling.
A temperature probe 19 is provided on the free end of the cord 17. Such probe is in the form of a small semiconductor diode 21 which is physically and electrically shielded from the surrounding environment by a thin sheath 20 of, for example, aluminum. As is known, the resistance of a semiconductive junction varies with the temperature of such junction. This phenomenon is utilized to provide an exceptionally accurate and inexpensive low power probe. More particularly, it has been found that if the flow of current through a semiconductor junction is maintained constant at a selected value, the voltage developed across the junction will be proportional to the temperature of the junction in an accurate straight line function. Thus, if current flow through a diode is maintained constant, measurement of changes in the voltage developed across the diode will provide a measurement of a temperature changes in such diode. And because a diode has a low mass and consequent low heat capacity, its temperature quickly reflects the temperature of its surroundings.
The diode probe is represented in the electrical diagram of FIG. 2 by the reference numeral 21'. As is illustrated, the input to such diode is provided by a shielded wire 22, through a resistor 25. The resistor 25 is provided for the purpose of matching the individual probe and cable combinations to the circuitry for a selected constant value of current flow. The return path for current flow is through the shielding 23. Both the lead 22 and the shielding 23 are part of the probe cord 17.
The disconnectable plug 18 is represented in FIG. 2 by the dotted line enclosure 18'. Such plug not only includes contacts 24 and 26 for connecting the temperature probe to the circuit within the casing, but also includes contacts 27 and 28 which act, in effect, as a single pole switch for connecting the serially connected batteries 29 and 31 to the remainder of the circuit. That is, such batteries are only connected to the circuit when the probe cord is in place.
It will be noted that the two serially connected batteries 29 and 31 have their common connection (the positive terminal of battery 31 and the negative terminal of battery 29) connected to the circuit via a lead 32, hereinafter referred to as the circuit common lead or bus. The positive terminal of battery 29 is connected to the circuit via a positive power bus 33, and the negative terminal of battery 31 is connected to the circuit via a negative power bus 34.
A semiconductor switching circuit is provided as a part of the thermometer for simultaneously connecting the buses 33-34 to the positive terminal of battery 29 and the negative terminal of battery 31, respectively, with a single pole switch as represented by the contacts 27 and 28. The batteries and this portion of the total circuit are set apart by the dotted line block 35. More particularly, a pair of transistors 36 and 37 are each connected between an associated one of the batteries 29 and 31 and one of the circuit buses 33 and 34, respectively. The transistor 36 is of the PNP type, whereas the transistor 37 is the NPN type. Thus, each of the transistors is connected between its associated battery and circuit buses in the direction of normal current flow through such transistor.
As is illustrated, the bases of the transistors are connected to one another through a resistor 38 and the single pole switch represented by the contacts 27 and 28. The resistance of resistor 38 is such that at the lowest useable voltage of the batteries, the base current generated by the circuit in each of the transistors will be more than sufficient to drive the transistors into saturation at the maximum operating current of the electronic thermometer circuit. The result is that upon closure of the switch represented by the contact 27 and 28, both of the transistors will be driven into saturation at substantially the same instant. This will, in effect, switch the batteries 29 and 31 into the circuit simultaneously. Thus, the inconsistencies and time delays inherent in double pole mechanical switches are avoided. The only difference in the time in which the differing potentials represented by batteries 29 and 31 are connected into the circuit will be due to the switching time differences between the PNP and NPN transistors. This potential time variation is much smaller than that which can be expected with a mechanical double pole switch. Moreover, any such variation will be consistent at all times so that, if necessary, compensation for it can be made.
Most desirably, the emitter to base reverse breakdown voltage of each of the transistors is in excess of the potential of the battery associated with the other transistor. Thus, if either or both of the batteries are installed incorrectly so as to reverse the polarity from that desired for the circuit, one or both of the base-emitter junctions will become reverse biased at a potential below the reverse breakdown voltage. This will reduce the reverse current going into the circuit to essentially zero, and thus will protect it from receiving power of reverse polarity. In this connection, polarity is used herein is measured from the potential on common bus 32 considered at zero potential.
The circuit of the electronic thermometer also includes means for automatically preventing erroneous operation of the electronic thermometer, i.e., inaccurate readings on the temperature scale, due to weak battery conditions. In this connection, it should be noted that although there are now available compensation circuits for maintaining accurate readings as a battery's voltage output diminishes, such circuits are not effective after the power of the battery reaches a certain low level.
The automatic battery cut-off portion of the circuit is included within the dotted line block 41. Such battery cut-off circuit includes operational amplifiers 42 and 43 respectively associated with the batteries 29 and 31. Such amplifiers act, in combination with diodes to be discussed, as means for both detecting when the associated battery reaches a predetermined reduced level below which erroneous readings may be expected, and as means for supplying a predetermined potential to the circuit to drive the indicator needle off scale and thereby indicate such reduced potential condition of a battery. Each of the amplifiers accomplishes this by first comparing the output voltage of its associated battery with a constant reference voltage. In this connection, a zener diode 44 is included with a resistance 45 to act as a constant voltage source. As shown, the positive primary input terminal of amplifier 42 is connected through a potentiometer 46 to the positive output of the battery 29 via circuit bus 33. The operational amplifier 43 is similarly connected across the battery 31, except that it is the negative output of battery 31 which is connected through a potentiometer 47 to its negative primary input terminal for comparison with a constant negative reference voltage provided by connecting its positive primary input terminal to the negative side of zener diode 44.
The positive and negative reference voltages applied respectively to the amplifiers 42 and 43 are chosen to be of lower magnitude than the positive and negative outputs of the batteries 29 and 31 when the powers of such batteries are in the operating range. Moreover, each potentiometer 46 and 47 is adjusted to provide its associated amplifier with an initially saturated positive output voltage when the batteries are at full potential (fresh). The particular voltage chosen via each potentiometer to be applied to the variable input terminal of each amplifier will depend on the predetermined low battery power level chosen to be the cut-off level. That is, the resistance provided by each potentiometer should be such that when the battery associated therewith reaches the desired cut-off potential, the voltage difference applied to the comparing input terminals of the associated operational amplifier will become zero.
It will be recognized that with the above arrangement, as each of the batteries weakens, the absolute value of the voltage difference applied through the potentiometer to the comparing input terminals of its associated operational amplifier will be correspondingly reduced toward zero. Until such zero potential difference is reached, the output terminal of amplifier 42, for example, is more positive than its positive input terminal. Thus, the diode 48 is reverse biased and essentially disconnects the feedback loop through resistance 49 from the output to such positive input terminal. However, upon the output terminal going slightly beyond zero to a negative condition, the diode 48 becomes forward biased and closes the positive feedback path around the amplifier. The result is that the amplifier rapidly drives itself into negative output saturation. Because of the circuitry to be described, this will immediately cause the needle (represented in FIG. 2 at 16') on the indicator 13' to be driven off scale. Moreover, the output of amplifier 42 will be held at negative saturation even if the voltage on its positive input terminal were to raise, i.e., the batteries were to show a spurt of additional power. Thus, the cut-off circuit not only initially drives the needle off scale when a low battery condition exists, but also maintains it there as long as the batteries are connected in the circuit to assure that no erroneous readings are obtained.
It will be noted that the output of amplifier 43 associated with battery 31 is connected through a diode 51 to the feedback path of amplifier 42. Thus, a condition of negative saturation on the output of amplifier 43 caused by the negative voltage provided by battery 31 on its negative input terminal becoming slightly positive with respect to its positive input terminal will be applied through the diode 51 and resistor 49 to the positive input terminal of amplifier 42. This will force the output of amplifier 42 to negative saturation as discussed above, which output is connected to the remainder of the circuitry. The amplifier 43 then provides, in effect, the same function for battery 31 as amplifier 42 provides for battery 29.
The output of amplifier 42 is connected through an isolating diode 52 to a measuring circuit set off in FIG. 2 by the dotted line block 53. Circuit 53 performs the actual measurement of voltage changes across the temperature probe diode 21' caused by temperature changes. As one of the most salient features of the instant invention, the measuring circuit has only one operational amplifier for providing both a constant current through the diode 21' and the amplifying voltage changes thereacross for appropriate operation of the indicator. More particularly, a feedback operational amplifier 54 is shown with its primary input terminals connected with the zener diode 44 so as to provide a constant voltage differential across the resistor 56 and, hence, constant current flow therethrough. That is, the negative (inverting) input terminal of the amplifier 54 is connected through the resistance 56 to the negative side of the diode 44, and the positive (non-inverting) input terminal of the amplifier is connected through a potentiometer 57 across such zener diode. As will be recognized, this, together with the negative feedback connection, will enable the required voltage differential across resistance 56 to be initially selected for a chosen constant current flow through the temperature probe.
The feedback connection of the operational amplifier from its output to its negative input terminal passes through the temperature probe 21. More particularly, a resistance 58 is provided in series with the probe assembly which is between the output of the amplifier and its negative input terminal. Because of the relatively constant voltage difference applied between the ends of the resistance 56, this feedback connection through the diode will result in the desired constant current flow therethrough whenever the circuit is operating. Thus, because of the constant current flow in the diode 21' whenever the resistance of the semiconductive material making up the diode 21' changes due to temperature changes, the voltage on the output of amplifier 54 will proportionately change to indicate such change. Because of the particular circuit relationships shown, the voltage change on the output of the amplifier will be inversely proportional in a straight line function to temperature changes on the probe diode. That is, as the temperature of the probe increases, the output voltage of amplifier 54 will move in a negative direction a proportionate amount.
As mentioned before, the amplifier 54 acts in combination with certain passive components to not only provide the constant current as discussed, but also to amplify the voltage change on its output caused by a temperature change. More particularly, a second resistance 59 is connected between the constant potential provided by the common bus 32 and a point 61 between the resistance 58 and the probe assembly. By appropriately selecting the ratio of the resistances 58 and 59, the voltage changes produced on the output of the amplifier 54 will be amplified compared to what they would be if the connection including resistance 59 were omitted. To appreciate this, it must be recognized that the current at the common connection 61 of the two resistances 58 and 59 to the diode 21' is maintained constant at all times because of the amplifier feedback connection. By making resistance 59 substantially smaller in value than resistance 58, the great majority of the current supplied at the connection 61 will be provided by the common bus 32. This will result in a larger variation in the output voltage of the amplifier 54 having to be applied through the resistance 58 to compensate for any change in the current flow through the resistance 59 caused by a change in the resistance of the semiconductive material 21'. Thus, the output of the amplifier 54 is an amplification of the voltage which would be required to maintain the current through the semiconductive material constant in the absence of the two resistance arrangement. The combination with the amplifier 54, then, of the three resistances 56, 58 and 59 in the circuit as described results in the amplifier providing the desired voltage amplification as well as a constant current through the temperature probe diode.
Most desirably, the point of zero potential across the meter is chosen to be representative of a temperature reading which is within the selected temperature range displayed on the indicator. Thus, whenever the probe is connected through the plug 18 to the circuitry, if the circuitry is operating, the needle will, in general, move. However, if the circuit is not operating, the needle will not move. Thus a user has a readily available visual check on whether or not the circuitry is in operation when the probe cord is initially connected to the circuit.
The circuit of the electronic thermometer further includes means for maintaining a peak temperature reading displayed on the meter for a predetermined period of time after the probe temperature starts decreasing. That is, when a temperature is taken and the indicator needle records the same, that portion of the circuit set apart by the dotted line block 62 holds the needle at the temperature reading for a selected period of time. More particularly, the capacitor 63 is charged by a potential representative of a peak temperature reading, which capacitor applies such potential to a current amplifying section of the circuit, set-off by the dotted line block 65, for a period of time dependent upon the holding circuit.
The peak temperature holding circuit 62 includes an operational amplifier 64 and a diode 66 for applying the output potential of the measuring operational amplifier 54 to the capacitor 63 without voltage loss. More particularly, the positive primary input terminal of the operational amplifier 64 is connected to the output of amplifier 54, and the negative primary input terminal of the operational amplifier is connected in inverse feedback relationship to the diode 66. This arrangement will result in the same voltage being applied across capacitor 63 as is applied to the positive input terminal of amplifier 64 by the output of measuring amplifier 54.
The timer for controlling the length of time the capacitor 63 maintains a peak reading on the meter includes a capacitor 67 which is connected through a resistance 68 to the output of measuring amplifier 54. An operational amplifier 69 has its negative input terminal connected on the measuring amplifier output side of the resistor 68, and its positive input terminal connected on the other side of such resistance, whereby the voltage drop across such resistance 68 due to changes in the output of the measuring amplifier is applied between the negative and positive input terminals of the amplifier 69.
As mentioned before, the output of measuring amplifier 54 is inversely proportional to a change in the temperature of the probe. Thus, upon the temperature of the probe increasing, the voltage drop across resistor 68 and, hence, the voltage applied across the operational amplifier 69 will be more negative on the measuring amplifier output side of such resistor than on the other. The result is that the output of operational amplifier 69 will be made positive. The circuit is so designed that the output of such amplifier also goes positive when the temperature reaches a stabilized condition. More particularly, at such time the output of the measuring amplifier 54 is constant with the result that there is no signal current flow through resistance 68. The resistance 77 has a value substantially above that of resistance 78. Thus, when the current flow through resistor 68 approaches zero, there is a larger voltage drop across resistance 77 due to the input currents of amplifier 69 than there is across resistance 78. Thus, the positive input terminal of the amplifier is positive relative to the negative primary input terminal, with the result that the amplifier output is made positive.
When the output of amplifier 69 is made to go positive a proportionate charge is made to build-up through a diode 71 on a capacitor 72. Moreover, the base of the transistor 74 will be positive, with the result that such transistor is placed in a conducting condition. Such transistor is connected between the negative input terminal of an operational amplifier 76 and a control terminal of the amplifier so that when the transistor is on, the output of such amplifier 76 is, in effect, off so that its output does not affect the potential indicative of a temperature rise provided on capacitor 63 by amplifier 64. As shown, the negative input terminal of the amplifier 76 is connected to its operating current control terminal so that its operating voltage is more negative than that on the positive input terminal when the amplifier is on. This assures that the output of amplifier 76 is positive when it is on so that the capacitor 63 is driven positive after the selected period of time.
As discussed previously, the potential on capacitor 63 is applied to the current amplifier section for display as a temperature reading on the indicator 13'. When the temperature starts decreasing such as when the probe is removed from a patient whose temperature is being measured, the timing circuit is activated to begin the timing operation and thereafter rapidly remove charge from capacitor 63 so that the peak temperature reading is no longer held. More particularly, when the temperature of the probe starts decreasing, the capacitor 67 applies its potential across the resistor 68 to reverse the relative polarity of the input terminals of amplifier 69, with the result that the output of such amplifier goes negative.
It should be noted that the feedback loop including resistor 79 and diode 80 from the output of amplifier 69 to its positive primary input terminal causes a slight "toggle" action to be superimposed on the change of the amplifier output from negative to positive. The value of resistance 77 on the negative input terminal is selected to be appropriately of a large value to cause the same kind of toggling action of the amplifier output in its change from positive to negative. This prevents minute changes in the probe temperature from reversing the output polarity of amplifier 69. Unwanted erratic switching of the timing circuit is thus avoided.
When the output of amplifier 69 is made to go negative whenever the temperature of the probe is decreasing, the capacitor 72 is discharged over a period of time dependent upon the value of resistance 81. The charge of capacitor 72 controls the voltage across resistance 82 and, hence, on the base of transistor 74. Thus, discharge of such capacitor results in a lowering of the potential on the base to the point where current flow through such transistor is turned off. The turning off of such transistor will apply the positive potential of bus 33 to the positive input terminal of the amplifier 76 through resistances 83 and 84 and to the negative input terminal through resistance 83 and diode 85. The output of the amplifier 76 will thus be made positive and will provide a positive voltage signal to capacitor 63 and provide a positive signal to the current amplifier 65 for driving the meter needle 16' off scale in the lower temperature direction. Thus, after the temperature of the diode 21' reaches its peak value and starts decreasing, the timing circuit holds the temperature reading provided by the needle 16' at such peak value for a predetermined time after the temperature of the diode 21' starts decreasing, and then automatically causes the meter needle to be displaced from such temperature reading so that further temperature measurements can be made.
The timing circuit is also arranged so that if during a temperature reading hold, the battery cut-off circuit 41 indicates a low battery condition, the temperature hold is released and the needle is driven off scale as discussed. More particularly, the output of amplifier 42 in the battery cut-off portion of the circuit is applied through a diode 86 to the base of transistor 74 so that when such output becomes negative as discussed above, the transistor will become turned off.
The current amplifier circuit 65 includes an operational amplifier 87 which acts almost identically to the operational amplifier 64, except that it acts to transmit the voltage applied to its positive input terminal to the positioning mechanism for needle 16' with the large current gain needed to operate such mechanism. More particularly, such amplifier controls the operation of a pair of NPN and PNP transistors 88 and 89 respectively, which are serially connected between the positive and negative input buses 33 an 34 of the circuit. That is, the output terminal of the amplifier 87 is connected to the base of each of such transistors to control current flow therethrough.
As is illustrated, the negative input terminal of the amplifier 87 is connected to the common emitter connection between the transistors 88 and 89. Thus, the amplifier 87 will act to set the voltage at the common emitter connection at the same voltage as that on its positive input terminal or, in other words, on the capacitor 63. However, because of the presence of the transistors, the current at such location will be greatly amplified relative to the potential current which could flow from the capacitor 63.
The temperature indicator is connected between the common bus 32 and the common emitter connection between the transistors 88 and 89. Thus, the high current signal voltage at such connection will also be applied to the indicator to control alignment of its needle 16' with temperature conditions as is desired.
Although not illustrated, it will be recognized that the electronic thermometer circuitry can include a conventional compensation circuit for assuring that the thermometer will be accurate over a wide range of ambient temperatures. The inclusion of such a compensation circuit is especially desirable for electronic thermometers to be used under the wide variations of temperature found outdoors.
It will be appreciated to those skilled in the art from the above description that the circuit of the electronic thermometer provides a precise and accurate translation of temperature changes of the probe semiconductive material to temperature readings on the indicator 13. It does so while requiring a minimum of power for operation and no non-automatic checking to be overlooked by an operator. And although the described embodiment includes all of the features provided by the circuitry as discussed above, it will readily be appreciated that the dual function amplifier portion of the circuitry has value separate and apart from the remainder of the circuitry even though it is especially useful in the instant combination. For example, the dual function amplifier is useable with other types of transducers and the like in which is it desired to maintain a constant current through a device and amplify any voltage changes in such device. Thus, it is intended that the coverage afforded applicant be limited only by the claims. | An electronic thermometer is described that is useful for obtaining oral or rectal body temperatures. The thermometer includes a casing on which is mounted a scale for visually indicating temperature readings. A plug-in connector is used to connect an electrical cord to the casing. Such cord terminates in a disposable semiconductor junction through which a constant current is made to flow so that the voltage developed across it is dependent upon its temperature in a straight line function. | 6 |
FIELD OF THE INVENTION
The instant invention relates to a method and apparatus for securely producing evidence of postage dispensed. More particularly, the instant invention is directed to a closed loop verification system of audit and control which enables the detection of fraud at postal facility counters and the collection of evidence to support a charge of such fraud against particular individual(s).
BACKGROUND OF THE INVENTION
In many countries there are post offices, under the physical control of a postal authority, where letters and packages can be mailed. An individual can walk into the post office and present their mailpiece to a postal clerk at the postal counter. The clerk will weigh the mailpiece to determine the appropriate postage required, collect the value from the individual (i.e. cash, credit card, etc.) to pay for the required postage, and print out and attach to the mailpiece evidence of postage paid.
FIG. 1 shows a traditional postal counter audit system 1 that is used to implement the procedure described above. The postal counter audit system 1 includes a personal computer (PC) 3 , a scale 5 , and a label printer 7 (which collectively form a postal counter system 8 ). The postal counter system 8 prints evidence of postage dispensed at the direction of the postal clerks. Each postal counter system 8 maintains a logfile in the PC 3 of all postage that it dispenses. The logfile data should match the value collected by the postal clerks for the postage dispensed.
As further shown in FIG. 1 , several postal counter systems 8 are commonly networked together along with an administrative computer 9 at a postal facility 10 . The administrative computer 9 is controlled by a postal administrator responsible for the proper operation of the postal facility 10 , e.g., a local postmaster. The postal administrator collects the logfile from each postal counter system 8 (electronically via the administrative computer 9 ). These logfiles are compared with the cash receipts (cash, credit card transactions, etc.) collected at each postal counter system 8 . Any discrepancies between the cash receipts and the logfiles are an indicator of potential fraud by a postal clerk. Additionally, all logfiles, or at least a summary of logfile data from the postal facility 10 , and a summary of cash receipt data are transmitted (over existing communication networks 12 ) to a postal funds management computer 11 . The postal funds management computer 11 also compares the received logfile data with the cash receipt data to determine if any discrepancies exist which would be evidence of potential fraud.
Unfortunately, existing postal counter audit systems 1 are subject to several types of fraud which may go undetected. Since the PC 3 includes a processor which is not a secure device, the logfiles stored in PC 3 may be easily tampered with by postal clerks that have access to PC 3 and some basic computer knowledge. As a result, a clerk could simply modify the logfiles (perhaps by deleting entries) and pocket the funds from the cash drawer associated with the modified records. Since the tampered logfiles would match the cash receipts, it would be difficult for a postal administrator to determine that a clerk was stealing postal funds. Moreover, an administrator (working on his own or in conjunction with a clerk) could also falsify records (logfile summaries and cash receipts) prior to transmission to the postal funds management computer 11 and such fraudulent activity might go undetected.
The above potential fraudulent activities are largely attributable to the fact that there is no prepayment of postage at a postal counter system 8 as there is with a conventional prepayment postage meter. That is, in a postage meter since the value contained therein has already been paid for, the problems associated with a cash basis transaction for postage does not exist. Accordingly, the instant invention is directed toward the detection of fraud in a “pay for postage as you dispense” counter operation and the collection of collaborating evidence in support of such fraud detection.
Additionally, the postal counter audit system 1 does not have a source of data, separate from the data transmitted from the administrative computer 9 (or the postal counter system 8 ) to the funds management computer 11 , that can be used to independently verify the data transmitted from the administrative computer 9 . For example, if the logfiles are altered as discussed above, there is no data feedback based on the processing of the actual mailpieces passing through the mailstream that is used to detect such fraud.
Yet another problem occurs when several people operate a single postal counter system 8 . In this situation, even if fraud is detected, it may be difficult to identify only those individuals committing the fraud.
Finally, another potential problem may exist if a postal clerk delays the reporting of logfiles. That is, if a postal clerk lags behind in sending out up to date logfiles, some of the cash received could be pocketed. In this situation the cash sent to the administrator would still match the transmitted logfiles which lag behind.
SUMMARY OF THE INVENTION
A method for auditing postage dispensing transactions at a postal facility includes the steps of: receiving in a secure processor based device a request to dispense an amount of postage; updating, in response to the request, accounting data within the secure processor based device to account for the amount of postage; cryptographically securing the updated accounting data in the secure processor based device; dispensing the amount of postage by generating and applying the cryptographically, secured, updated accounting data to a mailpiece. The method further includes receiving cash value for the amount of postage dispensed; sending from the secure processor based device to an administrative computer a cryptographically secure message including the updated accounting data; obtaining and comparing, at the administrative computer, the updated accounting data from the secure message with the cash value received and previous updated accounting data received from a previous secure message from the secure processor based device, and determining if any inconsistencies exist based on the comparing; and obtaining and analyzing, at a funds management computer, the updated accounting data from the mailpiece and the updated accounting data from the secure message and determining if any inconsistencies exist based on the analyzing. An apparatus incorporates the method.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate a presently preferred embodiment of the invention, and together with the general description given above and the detailed description of the preferred embodiment given below, serve to explain the principles of the invention.
FIG. 1 shows a prior art postal counter audit system;
FIG. 2 shows the inventive postal counter audit and control system;
FIG. 3 shows a representative example of a digital postage mark;
FIG. 4 describes the cryptographic elements used in the inventive a system of FIG. 2 ;
FIG. 5 shows a verification procedure; and
FIG. 6 shows an audit procedure implemented in the invention of FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The inventive postal counter audit and control system (PCACS) 13 , as shown in FIG. 2 , employs a combination of smart card technology, public key cryptography, administrative audit and control, and physical security to manage the security of postage value dispensed by postal clerks at a postal counter. The PCACS 13 includes individual postage dispensing counters 15 , an administrative computer 17 , a funds management computer 19 , a postal verification system(s) 21 and a certificate authority (CA) computer 23 .
The postage dispensing counters 15 each include a PC 15 a , a smart card reader 15 b , a smart card 15 c , a scale 15 d and a label/mailpiece printer 15 e . The purpose of the postage dispensing counters 15 are to provide a postal clerk the ability to create digital postage marks (DPM's 31 ) as evidence of postage dispensed by the postage dispensing counter 15 . That is, unlike existing postal counter systems 1 ( FIG. 1 ) that only print non-cryptographically secure evidence of postage dispensed, the postage dispensing counters 15 print cryptographically secure and verifiable DPMs 31 .
Referring to FIG. 3 , a representative DPM 31 is shown on a sealed mailpiece or sealed package 33 containing thereon a recipient address field 35 . The DPM 31 contains a dollar amount 37 , a date 39 that the evidence of postage was affixed to the mailpiece 33 , a location 41 that the mailpiece 33 was mailed from, a meter serial number 43 , the class of mail 45 , a FIM code 47 and a 2D bar code 49 . Bar code 49 includes cryptographically secured information that is derived from address field 35 and other information (such as the date 39 , serial number 43 , value of postage dispensed 37 , piece count, descending and ascending register values) generated or contained in the meter that affixed DPM 31 to the mailpiece 33 .
The cryptographically secured information contained in the bar code 49 may include all or only some of the data elements discussed above. However, whichever data is included it is digitally signed with the private key of the meter. Upon receipt of the mailpiece 33 , the cognizant postal authority can obtain the public key that corresponds to the meter private key in order to verify the authenticity of the cryptographically secured information and the DPM 31 .
Returning to FIG. 2 , the PC 15 a provides both the postal clerk interface and the communication interface between the smart cards 15 c and the administrative computer 17 . The smart cards 15 c provide a secure, cost-effective mechanism to distribute the ability to create DPMs 31 to postage dispensing counters 15 and to individual postal clerks. That is, each postal clerk can be assigned a specific (uniquely identifiable such as through a unique serial no.) smart card 15 c that provides the postal clerk with the ability to access the postal dispensing counters 15 via the card reader 15 b and the PC 15 a to create a DPM 31 . The smart card 15 c maintains a log of the postage dispensed from that smart card 15 c which log should be consistent with the cash received at the postage dispensing counters 15 . The DPM 31 is formatted for printing by the PC 15 a and printed on a mailpiece or label by the printer 15 d (preferably in machine-readable format such as the 2D barcode 49 ). As previously mentioned, each DPM 31 contains a digitally signed record (secret or public key infrastructures can be used) that indicates the smart card 15 c that produced the DPM 31 and the postage amount dispensed. In a preferred embodiment, the DPM 31 also contains the date and an indication of register values of the smart card 15 c.
The use of a smart card or a similar portable processing device in conjunction with a PC to create a verifiable DPM 31 as evidence of postage dispensed and to securely account for postage in the smart card is well known in the art as reflected in U.S. Pat. No. 5,781,438 which is hereby incorporated by reference. Accordingly, while a detailed description of such devices is not considered necessary for an understanding of the instant invention, a brief overview is considered helpful.
The smart card 15 c accounts for all of the evidence of postage value dispensed from it in an ascending register. Additionally, the amount of evidence of postage value at any given time that is permitted to be dispensed is reflected in the descending register. The sum of the ascending and descending registers is known as the control sum and will always reflect the total of authorized postage value that has been made available to the meter over its lifetime. Moreover, these registers together with the smart card's 15 c dedicated processor are all protected from a security attack by both physical and logical measures. Accordingly, the ability of an attacker to alter the accounting registers within the smart card 15 c is significantly reduced as compared to modifying the logfiles of the prior art postal counter systems 8 (FIG. 1 ).
Referring to FIGS. 2-6 , the operation of the PCACS 13 will now be described. When the smart card 15 c is in the reader 15 b and a postal clerk requests postage to be dispensed via the PC 15 a , the smart card 15 c accounts for the postage to be dispensed by adjusting the ascending and descending registers. Then, the smart card 15 c signs the ascending and descending register data together with the smart card 15 c serial number utilizing a private key V SC stored therein. The signed data is transmitted to the PC 15 a which forms the final DPM 31 image that includes the signed data. The PC 15 a then drives the printer 15 e to print the DPM 31 on a label or the mailpiece. Once the mailpiece is placed into the mailstream, the DPM 31 can be scanned and read at the verification system 21 for verification (in a known manner) and subsequent use in detecting fraudulent activity as discussed in more detail below.
In addition to the above, the PC 15 a may also store transaction logfiles which account for every postage dispensing transaction that takes place. Since the data in the logfiles consists of data signed by the smart card 15 c , any modification of logfiles data can be detected. These logfiles therefore can be used as yet another source of data by the administrative computer 17 and/or the funds management computer 19 to help detect fraudulent activity.
The administrative computer 17 provides a central point of local audit and control over the postage dispensing counters 15 at each postal facility 18 . In addition, the administrative computer 17 provides a communication interface between postage dispensing counters 15 and the certificate authority computer 23 , the postal verification computer 21 and the funds management computer 19 . Each administrative computer 17 is capable of auditing the functions of each smart card 15 c , collecting data from each smart card 15 c and its associated PC 15 a , enabling and disabling each smart card 15 c , and controlling the amount of postage each smart card 15 c is able to dispense. Therefore, the administrative computer 17 provides the postal authority with local control of the individual postage dispensing counters 15 within the postal facility 18 .
The certificate authority computer 23 is responsible for certifying the “identity” of the administrative computer 17 and the smart cards 15 c . Each administrative computer 17 contains a unique private key V Admin which is used to sign messages that enable, disable, or add funds to smart cards 15 c . Each smart card's 15 c unique private key V SC is used to sign messages from the smart card 15 c . The certificate authority computer 23 provides a certificate to each smart card 15 c and each administrative computer 17 . Each certificate (Admin cert , SC cert ) is the respective public key (U Admin , U SC ) of the administrative computer 17 and the smart card 15 c , as the, case may be, signed with the private key V CA of the certificate authority.
The postal verification system's 21 computer checks the validity of DPMs 31 , maintains a log of mail processed based on the scanned DPM's 31 , and transmits the data retrieved from the scanned DPMs 31 to the funds management computer 19 . The verification system 21 stores a copy of each smart card's 15 c certificate SC cert in order to verify DPMs 31 (alternatively the SC cert can be included as part of the DPM 31 ). That is, in one embodiment, the DPM 31 includes a unique identifier that identifies the smart card 15 c that produced the DPM 31 , the amount of postage dispensed and associated with the particular DPM 31 , and at least the ascending register value (and preferably the descending register value as well) of the smart card 15 c , all of which is signed using the private key V SC of the smart card 15 c . As shown in FIG. 5 , the verification computer 21 receives the cryptographically secure DPM 31 data which has been scanned off the mailpiece during the processing of the mailpiece in the mailstream (step S 100 ) and obtains the smart card 15 c data (register readings, postage amount, date postage dispensed, smart card identification) contained therein (step S 102 ). The verification computer 21 then determines whether the specific smart card 15 c has been flagged as being on a suspect list and whether it appears on a certificate revocation list (CRL) (step S 104 ). The suspect list identifies smart cards 15 c that have been designated as having been potentially used in a fraudulent manner while the CRL identifies smart cards 15 c having an expired certificate SC cert . If the particular smart card 15 c appears on the suspect list or the CRL, an investigation is initiated (step 112 ). Assuming the particular smart card 15 c does not appear on the suspect list or the CRL, the verification computer 21 uses a certificate authority root certificate CA cert to obtain the public key U CA of the certificate authority. The public key U CA of the certificate authority is then used to obtain the public key of the smart card 15 c from the smart card 15 c certificate SC cert so that the DPM 31 can be verified in a known manner (step S 106 ). If verification is not successful, an investigation is initiated at step S 112 . If verification is successful, the verified data is sent to the funds management computer 19 where it is used as data independent from data received from either the administrative computer 17 , the PC 15 a or the smart cards 15 c . Accordingly, any inconsistencies detected between register, postage amount or date data obtained from the mailpiece and similar data received from the administrative computer 17 , PC 15 a or the smart cards 15 c provides an indication of potential fraudulent activity and ensures the robustness of the inventive PCACS 13 as compared to the prior art system 1 . For example, if the funds management computer 19 identifies an inconsistency in ascending register data (step S 108 ) it starts an investigation (step S 112 ). On the other hand, if the ascending register check is valid, the funds management computer 19 determines if this particular DPM 31 is redundant with that of a previously processed mailpiece 33 (step 110 ). If it is, an investigation is started (step S 112 ), however if it isn't, the funds management computer 19 just logs in the results of all of the checks at step S 114 .
Referring to the flowchart of FIG. 6 , the flow of data between the smart card 15 c , administrative computer 17 , and funds management computer 19 will be discussed. The administrative computer 17 issues a challenge to a smart card 15 c (step S 201 ). The smart card 15 c prepares an audit message in response to the challenge by signing its internal data (e.g., register values, status, failure counts, identifier) and the challenge using V SC (step S 203 ). The audit message, transaction logfiles from PC 15 a and SC cert are then sent, via the PC 15 a , to the administrative computer 17 (step S 205 ). The administrative computer 17 then verifies the audit message (step S 207 ). If verification is successful, the administrative computer 17 compares the internal data with previous internal data received from the smart card 15 c , the transaction logfiles, any funds transfer operations previously performed by that administrative computer 17 with respect to the particular smart card 15 c , and cash data (step S 209 ). In the event that all of the compared data is consistent (step S 211 ), the administrative computer 17 forwards the audit message, logfiles, and cash receipt data to the funds management computer 19 where similar consistency checks are performed (step S 213 ). On the other hand, if an inconsistency is found at step S 211 or verification fails at step S 207 , an investigation as to whether fraudulent activity has occurred is initiated at step S 115 .
In another embodiment, the funds management computer 19 also has the option of providing the challenge to the smart card 15 c (via the administrative computer 17 ). This allows tampering with the administrative computer 17 to be detected (e.g., an administrator who collected a number of audit messages from a smart card 15 c over the course of a day and sent them to the funds management computer 19 over a number of days to cover up that he was pocketing some of the cash received at the postal facility).
As previously discussed, each smart card 15 c has a descending register having a value that limits the amount of evidence of postage that can be dispensed from the smart card 15 c . The administrative computer 17 is provided with the capability to authorize an increase in the value stored in the descending register. The administrative computer 17 , under control of an administrator, signs a message (including a transaction number to avoid replay attacks) using V Admin indicating an amount of value to be added to the descending register of a particular smart card 15 c . The signed message is sent together with the Admin Cert to the smart card 15 c which verifies the command using Admin Cert . Upon successful verification of the message, the smart card 15 c adds the amount of value to its existing balance in the descending register. The postage refill process described above should be preceded and followed by an audit of the smart card 15 c register values. It should also be noted that in some systems there is not a requirement for a descending register value such that no limit is imposed on the amount of evidence of postage that can be dispensed.
Local control of the smart cards 15 c by the administrative computer 17 is further provided by the administrative computer's 17 ability to enable and/or disable individual smart cards 15 c . That is, if a particular smart card 15 c is designated as requiring activation (enable) or deactivation (disable) the administrative computer 17 signs a message (including a transaction number to avoid replay attacks) using V Admin indicating that a particular smart card 15 c should be enabled or disabled. The smart card 15 c verifies the message, using Admin Cert that has been provided by the administrative computer 17 . Upon successful verification, the smart card 15 c either enables or disables itself. The smart card 15 c enable/disable process should be preceded and followed by an audit of the smart card 15 c registers. The result of all smart card 15 c enable/disable attempts (including smart card register values) is sent by the administrative computer to the funds management computer 19 . U.S. Pat. No. 5,809,485 describes a system for disabling a smart card in a postage meter and is hereby incorporated by reference.
In order to increase the overall security of the PCACS 13 , each of the smart cards 15 c and administrative computer 17 , on a periodic basis, must generate a new key pair (private and public key) and request a certificate from the CA computer 23 . This is accomplished by executing the following steps:
A. The smart card 15 c or administrative computer 17 generates a key pair (V new and U new ) B. The smart card 15 c or administrative computer 17 signs the new public key, U new , with the new private key, V new (this ensures that the smart card 15 c or administrative computer 17 knows the private key that corresponds to the public key C. The smart card 15 c or administrative computer 17 incorporates the result in a certificate request signed with the smart card 15 c or administrative computer 17 existing private key, V existing D. The smart card 15 c or administrative computer 17 sends the certificate request and the smart card's 15 c or administrative computer's 17 existing certificate to the CA (Due to a potential delay between a new certificate request actually receiving the certificate, smart cards 15 c store both the old and new key pairs in nonvolatile memory until a valid certificate for the new key has been received) E. The CA computer 23 verifies the request and signs a new certificate for the smart card 15 c or administrative computer 17 F. The CA computer 23 sends the certificate to the smart card 15 c or administrative computer 17 G. The smart card 15 c or administrative computer 17 verifies the certificate and then begins using the new key pair and its associated certificate.
The PCACS 13 as described above provides improved fraud detection capabilities as compared to the prior art postal counter solutions. For example, if a smart card 15 c is reported as lost, stolen, or as having produced DPM's 31 with inconsistent data from that scanned off the mailpiece, it can be placed on the suspect list. Subsequent mailpieces having DPMs 31 produced by that smart card 15 c will be detected during the verification process as being on the suspect list. This allows the mail operator to suspend delivery of such mailpieces pending an investigation.
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. For example, while the preferred embodiment shows an open metering system that uses a smart card 15 c , a PC 15 a , and a printer 15 e , a closed system metering device could be used as well. The closed metering device produces a DPM 31 as evidence of postage but typically includes in a single secure housing a processor, the accounting registers, and a dedicated printer as is known in the art. Furthermore, in another embodiment local control of the postage dispensing counters 15 can be relinquished by eliminating the administrative computer 17 and putting all of its functionality at the funds management computer 19 . Finally, smart cards 15 c can be designed to be operative only with a single administrative computer 17 to preclude the use of different smart cards 15 c at multiple postal facilities 18 . | A method for auditing postage dispensing transactions at a postal facility includes the steps of: receiving in a secure processor based device a request to dispense an amount of postage; updating, in response to the request, accounting data within the secure processor based device to account for the amount of postage; cryptographically securing the updated accounting data in the secure processor based device; dispensing the amount of postage by generating and applying the cryptographically, secured, updated accounting data to a mailpiece. The method further includes receiving cash value for the amount of postage dispensed; sending from the secure processor based device to an administrative computer a cryptographically secure message including the updated accounting data; obtaining and comparing, at the administrative computer, the updated accounting data from the secure message with the cash value received and previous updated accounting data received from a previous secure message from the secure processor based device, and determining if any inconsistencies exist based on the comparing; and obtaining and analyzing, at a funds management computer, the updated accounting data from the mailpiece and the updated accounting data from the secure message and determining if any inconsistencies exist based on the analyzing. An apparatus incorporates the method. | 6 |
BACKGROUND OF THE INVENTION
Although manufacturers of galvanic cells for many years have attempted to produce a better cell having longer life, higher current drains and greater outputs by improving upon one or more elements of the cell, one area that has continued to be less than totally satisfactory has been the construction of the separator used in the galvanic cell.
In conventional alkaline type MnO 2 dry cells, the cell construction generally consists of a metal container, suitably of steel, a mass or mix of MnO 2 and graphite molded within the steel case, a separator adjacent to the MnO 2 mass and an electrolyte and anode material in the center of the separator. The separator serves both as a barrier against migration of the depolarizer mix and the anode. In the past, it has been found convenient and practical to employ a cellulose based separator such as one constructed of paper, pulpboard, alpha cellulose, cellulose acetate, pasted kraft board, methyl celluose film and non-woven paper of cellulose fibers laminated to a similar mat of vinyl fibers. More recently, polyvinyl acetate sheeting has been employed as a separator material for its ability to prevent migration of depolarizer and to provide dimensional stability.
Conventionally, separators have been made by wrapping the separator around the sides of a bobbin and by folding the separator across the bottom of the bobbin before it is inserted within the cell. Usually, one or more washers were employed at the bottom of the bobbin to lock the folded edges of the separator against the bottom of the cell. However, separators of this construction suffer from many disadvantages. These separators, because they are wrapped around the bobbin before it is inserted within the cell, tend to loosen. As the separator must be tight to contain the particles of depolarizer mix, migration of these particles is likely to occur. Another disadvantage is that the folded bottom of the separator, even when washers are used to lock the folded edges are bulky and take up space within the cell.
To provide more room within the cell, the prior art developed a method of forming a separator by forcing a strip of separator material through a die with a punch and inserting the formed separator into the cell container which is mounted to the forming die. One such method is described in U.S. Pat. No. 3, 089,914 to Carmichael et al.
Although such prior art procedures provided reasonably satisfactory results with paper separators, it has been found that when the separators are constructed of relatively stiff, resilient materials, the separator walls, due to the resiliency of the material employed, tend to contract or coil inwardly toward the center of the cell thereby reducing the size of the opening into which the anode material is poured during the filling operation. This results in serious problems in high speed assembly of alkaline cells as the narrowed orifice reduces the free space available for anode material thereby providing a cell with a shortened life and frequently causes spill over of anode material onto the cathode with a resulting shorting and rejection of the cell.
It is therefore an object of the present invention to provide an improved separator construction for a galvanic cell.
Another object is to provide a method and apparatus for forming the separator in place within the shell of the galvanic cell.
SUMMARY OF THE INVENTION
According to the present invention, there is now provided an improved method of separator construction for a galvanic cell having at least two cup shaped separator linings, each of which consists of a circular bottom and cylindrical side walls composed of two overlapping semi-cylindrical wall segment and which comprises employing a thermoplastic separator material which, upon formation into a separator, is sized within the cell with a sizing punch at a temperature and for a period of time sufficient to deform the thermoplastic material against the cathode material and to fuse its seams without degrading the mechanical integrity and the migration resistance and insulating properties of the separator.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is an exploded view of the separator construction of the invention prior to sizing;
FIG. 2 is an exploded view of the separator construction of the invention after sizing;
FIG. 3 is a sectional view of a typical cell embodying the invention;
FIG. 4 is a vertical sectional view of the punch apparatus before insertion into the separator;
FIG. 5 is a vertical sectional view of the punch apparatus showing the punch in position within the separator in the cell.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, there is shown in FIG. 1 an exploded view of a separator construction according to the invention which comprises an outer and an inner cupped shaped separator lining 12, 12', preferably of a thermoplastic material such as polyvinyl acetate. The separator linings 12, 12' are formed one inside the other and then placed within the case of a galvanic cell such as the cell shown in FIG. 3.
As shown in FIG. 3, an alkaline cell 20 of the type of construction for which the invention is well suited typically comprises a steel case 22 which serves as the container for the cell, a cathode 24 consisting of MnO 2 , a separator 26, an anode 28 containing KOH and amalgamated zinc and an anode conductor tip 29.
According to the present invention, an alkaline cell such as is shown in FIG. 3 may be provided with a separator construction 10 comprising an outer and an inner cupped shaped separator lining 12, 12', preferably of polyvinyl acetate, which are formed in place within the metal shell containing the pre-formed cathode material.
The separator linings 12,12', referring again to FIG. 1, are each formed from a single blank of separator material and comprise a circular bottom, shown at 30 and cylindrical side walls composed of two semi-cylindrical wall segments 31,32 and 31',32' having overlapping edges 34,35 and 34',35' respectively. The excess separator material at the bottom edge of each separator linings 12,12' is gathered neatly into folded tabs 36 which are folded against the cylindrical side walls. The tabs 36 of the separator linings 12,12' are intended to prevent the overlapping lateral edges 34,35 and 34',35' from separating but because of the stiffness of the thermoplastic separator material, do not lie compactly against the side walls. The fusing of the thermoplastic separator material permits the formation of a hemispherical bottom with the tabs sealed tightly to the cylindrical side walls of the separator linings as is shown in FIG. 2. The lateral ovelapping edges 34,35 and 34',35' of each separator lining 12,12', respectively, occupy spaced radial positions about the circumference of the cylindrical side walls of the separator construction. The overlapped edges are heat sealed by action of the heated punch 40, thus providing increased anode volume and preventing migration of particles of depolarizer mix and anode material through the overlapping lateral edges 34',35' of the inner separator lining 10'
Apparatus for carrying out the method shown in FIGS. 4 and 5 comprises a cylindrical heated resize punch 40, a heater block 42. The resize punch is heated in the heater block, the temperature being controlled by thermocouple 44.
As will be seen in FIG. 4, heated resize punch 40 is axially positioned within an axial bore located in heater block 42 which consists of a brass body 46 surrounded by a heater band of conventional design (not shown) connected to a source of electrical power. Heated punch 40 is moved along its axis by a stroke control air cylinder (not shown) which raises and lowers the punch. As the separator and cathode cell assembly is indexed below heated punch 40, a controller (not shown) signals a pneumatic system to cycle the punch in and out of the cell assembly. The heated punch, depending on the assembly line configuration, may be assembled in multiples, preferably multiples containing four heated punches per station.
It has been found that when heated punch 40 is provided with a hemispherical bottom, the bottom of the separator conforms tightly to the bottom of the preformed cathode cavity 48 and minimizes bulges in the folds with their resultant waste of space.
In carrying out the method of the present invention, the separator lining 12, 12' is formed by methods well known in the art and the formed separator is inserted into the cell shell. The heated punch 40 is lowered from heater block 42 into the center cavity formed by the cylindrical walls of separator 12,12', forcing the side walls and bottom of the separator construction tightly against the preformed cathode. Heated punch 40 is maintained at a temperature and for a time sufficient to deform the thermoplastic separator without degrading it. Where polyvinyl acetate is the separator material employed, the heated punch will be maintained at a temperature of below about 180° F., preferably at a temperature of about 135° F. to about 160° F. and most preferably at a temperature of about 141° F. The length of time heat punched 40 remains in in contact with the separator material will vary with the composition of the thermoplastic material and the temperature of the punch. However, in all cases the time and temperature must be such as to avoid degradation of the separator material. Where polyvinyl acetate is employed, the time the heated punch is kept in contact with the separator will be less than 0.2 seconds and preferably less than 0.1 seconds.
It will be apparent that the length and diameter of the heated punch may vary, depending on the diameter and length of the cell in which the separator material is to be sized. | The present invention relates to an improved method for sizing thermoplastic battery separators introduced into partially assembled cells. The method comprises introducing a heated sizing punch under controlled temperature and time conditions to deform the formed thermoplastic separator and to seal its seams without degrading the separator material. | 8 |
BACKGROUND OF THE INVENTION
a. Field of the Invention
The present invention relates to a device for automatically detecting an overload on an aerial ladder truck.
Generally, in an aerial ladder truck, the operator carefully operates the ladder so that the load will not exceed the working limit range on the basis of a working limit range diagram as shown in FIG. 1 taking into account the strengths of the ladder and other parts and the safety of the truck against toppling. Therefore, the truck is usually provided with a warning device or an automatic stopping device which operates in accordance with said working limit range diagram.
B. Description of the Prior Art
The conventional warning or automatic stopping arrangement, as shown in FIG. 2, comprises a load detecting cylinder 3 disposed adjacent the ladder support point 2 of a ladder support frame 1, a pressure switch 4 into which the pressure in the cylinder is introduced, a load detecting rod 5 which is pressed by the lower surface of a ladder 6 to detect the pressure in the cylinder, the arrangement being such that when said pressure takes a value specified by the pressure switch, a warning device or automatic stopping device (not shown) is actuated by the action of the pressure switch.
In this connection, a detection pressure to the load detecting cylinder produced by a front end load should be the same regardless of whether the ladder assumes a condition A or B shown in the diagram of FIG. 1. However, the pressure due to the self-weight of the ladder is greater in the condition B than in the condition A since the center of gravity of the ladder is located more outwardly in the condition B than in the condition A. Thus, eventually the detected pressure is greater in the condition B than in the condition A. If the detected pressure in the condition A is selected as the specified pressure of the pressure switch, then in the condition B the pressure switch reaches the specified pressure and the warning device or automatic stopping device is actuated before the working range is reached. This is due to the fact that the pressure actually detected by the load detecting cylinder differs between the conditions A and B.
SUMMARY OF THE INVENTION
The present invention is adapted to detect a load acting on the support portion of a ladder and the vertical angle of the ladder so that the safety working range of the ladder may be set in an optimum condition in each case.
The construction of the invention will now be described with reference to the drawings showing an embodiment thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a working limit range diagram for an aerial ladder truck;
FIG. 2 is an explanatory view of a conventional device;
FIG. 3 is a view of a device according to the present invention; and
FIG. 4 is an explanatory view of the principal portions of the device of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference is now to be had to FIGS. 3 and 4 wherein a portion of an aerial ladder truck is shown which includes a truck body 10, a turntable 11 mounted thereon, a ladder support block 12 mounted on the turntable 11, a ladder support frame 13 mounted on the turntable 11 by means of a shaft 14 so that the support frame 13 is vertically swingable relative to the ladder support block 12 by means of a hydraulic cylinder (not shown), a ladder assembly 15 mounted at its lower end to the ladder support frame 13, and stop means 16 associated with the support frame 13 to stop the ladder movement, the ladder assembly otherwise being suitably supported at its lower end to the support frame 13 so that it will not slip down or jump up.
The constructions of vertical angle detecting means 100 and load detecting means 200 which constitute the principal portions of the present invention will now be described. The vertical angle detecting means 100 of the ladder assembly comprises a first chain wheel 17 fixed to the rotary shaft 14, a second chain wheel 18 mounted on the ladder support block 12, a chain 19 connecting the two chain wheels 17 and 18, an angle pointer 21 secured to the rotary shaft 20 of the second chain wheel 18, and a fixed disc 23 having a plurality of contacts 22 arranged thereon in a circle. The contacts 22 mounted on the fixed disc 23 are arranged so that they are successively contacted by the angle pointer 21 when the ladder is vertically swung through predetermined successive angles. In the arrangement shown in the drawing, they are contacted by the angle pointer 21 when the vertical angle of the ladder is 30°, 40° and 68°. In addition, the character 24 designates an electric power source having its negative pole grounded and its positive pole connected to the rotary shaft 20.
The load detecting means 200 comprises a first liquid pressure producing cylinder 25 installed adjacent the stop 16, a second cylinder 26 provided on the ladder support block 12 and adapted to be actuated by the liquid pressure from the first cylinder, a load pointer 27 adapted to be rotated through an angle proportional to the liquid pressure of the second cylinder, and a fixed disc 29 having a number of contacts arranged thereon in a circle. The contacts provided on the fixed disc 29 are arranged so that they are contacted by the load pointer 27 when the load acting on the stop 16 reaches c Kg/cm 2 , b Kg/cm 2 and c Kg/cm 2 (where c b a). The first and second cylinders 25 and 26 are interconnected by a pipe 30, and the two chambers interconnected by the pipe 30 are liquid-tightly filled with liquid 31. The piston rod 32 of the first cylinder 25 abuts against the rear surface of the ladder, while the piston rod 33 of the second cylinder 26 is formed with a rack 34, which meshes with a pinion 36 fixed to the rotary shaft 35 of the load pointer 27. The piston rod 37 of the second cylinder 27 is acted upon by a spring 38 which acts against the liquid pressure. A warning device or automatic stopping device 39 is provided in a suitable place on the truck body and electrically connected to the rotary shaft 35 of the load pointer 27.
The contacts 22 on the fixed disc 23 of the vertical angle detecting means 100 are electrically connected to the contacts 28 on the fixed disc 29 of the load detecting means 200 in a manner shown in FIG. 4.
Thus, as the vertical angle of the ladder is increased, the load detected by the load detecting means 200 is decreased even if the same load acts on the ladder. In order to cope with this situation, the contact corresponding to the vertical angle of 30° is connected to the contact at c Kg/cm 2 ; the contact corresponding to 40° is connected to the contact at b Kg/cm 2 ; and the contact corresponding to 68° is connected to the contact at a Kg/cm 2 . In this case, the detected pressures are in the relation a< b< c . That is, as the vertical angle is decreased, the detected pressure is increased.
In addition, in FIG. 4, the contact at 68° is connected to the contacts at a Kg/cm 2 , b Kg/cm.sup. 2 and c Kg/cm 2 . This is an example of an arrangement in which with the ladder taking a vertical angle of 68°, when the pressure detected by the load detecting means 200 is a Kg/cm 2 or above, the warning device or automatic stopping device 39 is actuated. This means that when the vertical angle is 68°, the means 39 is actuated at the pressure of a Kg/cm 2 and also actuated at the pressures of b Kg/cm 2 and c Kg/cm 2 which are greater than a Kg/cm 2 .
Within the same meaning, the contact at 40° is connected to the contact at b Kg/cm 2 and also to the contact at c Kg/cm 2 .
Similarly, the contact at 30° is connected to the contact at c Kg/cm 2 and to other contact or contacts (not shown) corresponding to pressure or pressures greater than said c Kg/cm 2 .
The operation of the warning device or automatic stopping device 39 will now be described.
Assume that the vertical angle of the ladder is 68° and that at this vertical angle, the working limit pressure of the ladder is set at a Kg/cm 2 . If the load pointer 27 of the load detecting means 200 indicates a Kg/cm 2 , an electric current flows from the power source 24 through the pointer 21, 68° contact, a Kg/cm 2 contact and pointer 27 into the warning device or automatic stopping device 39, whereby the latter is actuated. It goes without saying that with the ladder taking a vertical angle of 68°, when the pointer 27 of the load detecting means detects a load of above a Kg/cm 2 , said device 39 is actuated. Therefore, the device 39 is actuated when the pointer 27 is contacted with a contact corresponding to a pressure greater than a Kg/cm 2 , such as b Kg/cm 2 and c Kg/cm 2 .
Further, with the vertical angle of the ladder being 40°, when the pointer 27 of the load detecting means 200 indicates b Kg/cm 2 , the device 39 is actuated, and it is also actuated when the pointer 27 indicates a Kg/cm 2 , which is greater than b Kg/cm 2 .
Further, with the vertical angle of the ladder being 30°, when the detected pressure is c Kg/cm 2 or above, the device 39 is actuated.
In addition, it is necessary to put a diode in each line so that electric current does not flow from the fixed disc 29 of the load detecting means 200 to the fixed disc 23 of the vertical angle detecting means 100.
In brief, according to the present invention, the two means 100 and 200 are adapted to be independently operated so that when a predetermined condition is established the warning device or automatic stopping device 39 is actuated. Upon actuation of the device 39, the operator manipulates the ladder to the safety side.
With the above-mentioned arrangement, toppling of the ladder truck during ladder operation can be avoided. In any operating conditions including the vertical angle and degree of extension of the ladder, the bending moment, compression and tensile stresses in the ladder itself can be maintained within the allowable ranges.
In other words, according to the conventional pressure detecting system shown in FIG. 2, if a load acting on the ladder is represented by w, the distance form the load detecting cylinder to the loaded point by L and the vertical angle of the ladder by α, then the detected pressure p is:
p˜Lw cosα
Thus, the value of p is increased as the ladder approaches the horizontal, or conversely, it is descreased as the ladder approaches the vertical. In an extreme case, if the ladder is erected upright, the α is 90° and hence cos is zero, so that the value of p is zero. In this condition, therefore, however high the load w may be, the danger cannot be detected. In such condition, if the load w is increased, a compressive load is applied to the ladder causing buckling of the ladder, so that there is the danger of the ladder being broken.
The present invention is capable of coping with such situation.
Whiles there have been described herein what are at present considered preferred embodiments of the several features of the invention, it will be obvious to those skilled in the art that modifications and changes may be made without departing from the essence of the invention.
It is therefore to be understood that the exemplary embodiments thereof are illustrative and not restrictive of the invention, the scope of which is defined in the appended claims and that all modifications that come within the meaning and range of equivalency of the claims are intended to be included therein. | A safety device is provided for association with an aerial ladder truck assembly to automatically detect a weight overload on the ladder unit of the assembly at any given angle. The safety means are characterized by providing ladder angle detecting means in the form of a disk provided with a plurality of contacts and a pointer operatively associated with the ladder which engages a given contact at a given angle position of the ladder, and a load indicating means which actuate a pointer mounted on a disk provided with a plurality of contacts, each of which indicates a load value with the angle indicating contacts and the load indicating contacts of each disk being electrically connected to one another and an alarm device to give an alarm when there is a weight overload on the ladder unit at the angle it is positioned. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to home phoneline networks generally and to such networks with mixed types of network devices in particular.
BACKGROUND OF THE INVENTION
[0002] The Home Phoneline Network Alliance (HPNA) has defined a set of standards of how to manage a data network transmitted over the phone lines in a home (rather than along separate data lines).
[0003] In HPNA v.2, the network devices are asynchronous network devices, sending messages when they sense that the network medium was available. The asynchronous network devices have collision detection (CD) abilities and can detect if another network device is transmitting at the same time that they do. If so, both network devices back off for a random amount of time after which, they retransmit the packet. Such a back off system works well for a small number of network devices, but, since the back offs are for a random amount of time, the HPNA v.2 network devices cannot guarantee quality of service for services with specific timing requirements, such as voice over IP (VOIP) or video downloads.
[0004] The most recent standard, HPNA v.3, defines a network that attempts to guarantee quality of service (QoS) requirements while being retro-compatible with the previous network devices. HPNA v.3 requires that its network devices operate synchronously, each network device being allowed to transmit only during the timeslots assigned to it. For this, at least one of the network devices has a scheduler to assign the timeslots so as to guarantee media resources to network devices, to prevent collision between multiple network devices using the same line and to ensure quality of service. The asynchronous network devices, either an HPNA v.2 network device or a non-HPNA network device, do not know the boundaries of the timeslots and thus, transmit whenever they sense that the medium is available. HPNA v.3 includes rules for handling such interruptions in the transmissions so as to minimize the effect such interruptions have on the quality of service.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The subject matter regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, both as to organization and method of operation, together with objects, features, and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanying drawings in which:
[0006] FIG. 1 is a schematic illustration of a novel data network for mixed types of network devices, constructed and operative in accordance with the present invention;
[0007] FIG. 2 is a schematic illustration of an exemplary media access plan (MAP);
[0008] FIGS. 3A and 3B are timing diagram illustrations of two transmission scenarios with the same MAP, useful in understanding the operation of the present invention;
[0009] FIG. 4 is a schematic illustration of an exemplary MAP with a registration timeslot for non-telephone network devices;
[0010] FIG. 5 is a schematic illustration of an exemplary embodiment of the present invention with mixed telephone and coax wiring; and
[0011] FIG. 6 is a block diagram illustration of a non-telephone network device forming part of the present invention.
[0012] It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.
DETAILED DESCRIPTION OF THE INVENTION
[0013] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the present invention.
[0014] Reference is now made to FIG. 1 , which depicts a novel data network 8 , for mixed types of network devices. As in the prior art, data network 8 may comprise synchronous network devices Si, such as HPNA v.3 network devices, and asynchronous network devices Aj, such as HPNA v.2 network devices and others. For example, FIG. 1 shows three synchronous network devices S 1 , S 2 and S 3 and one asynchronous network device A 1 . It will be appreciated that there may be fewer or more devices in the network, as desired.
[0015] In accordance with a preferred embodiment of the present invention, data network 8 may also comprise non-telephone network devices NTk, where k may be any integer 1 or above, which operate without collision detection. These novel units may provide HPNA services to network devices connected to the network with wiring other than telephone wiring (shown in FIG. 1 with double lines). For example, non-telephone network devices NTk may be connected through cable wiring, power line wiring or even a wireless connection 10 .
[0016] Except for the collision detection, non-telephone network devices NTk may perform most of the HPNA v.3 operations. Thus, they may sense when the medium is and is not available (known as “carrier sensing”), may receive transmissions sent to them, and may operate synchronously, transmitting during the timeslots assigned to them. However, since they do not detect collisions, they may be unable to determine if another network device transmitted at the same time that they did and thus, may have difficulties transmitting during “contention periods”, when any network device is allowed to transmit, or during any other timeslot assigned to more than one network device. Typically, non-telephone network devices NTk may transmit during contention periods in order to request a timeslot or a change in timeslot allocation. Since they cannot determine if their transmission collided with another, the only way for them to determine if their transmission was received is to wait for an acknowledgement from the recipient of their transmission.
[0017] In HPNA v.3, there is a “master” responsible for generating a media access plan (MAP), defining the timeslot allocations for the network devices requiring services. U.S. Ser. No. 10/127,693, for “Adaptive Synchronous Media Access Protocol For Shared Media Networks”, is assigned to the common assignee of the present application and describes the MAP used for HPNA v.3. U.S. Ser. No. 10/127,693 is incorporated herein by reference.
[0018] FIG. 2 , to which reference is now made, illustrates an exemplary MAP 40 such as may be used in HPNA v.3. MAP 40 is a detailed schedule of future transmission opportunities (TXOPs) that will be made available to the synchronous network devices in an upcoming cycle and allocates each opportunity to a particular service. MAP 40 details the start time and length of each scheduled TXOP 44 , 48 , 50 , 54 in the next cycle of transmissions, and assigns each TXOP to a particular network device. For example, TXOP 44 may be the first TXOP and may be assigned to a digital telephony service from network device S 3 . TXOP 50 may be the third and it may be assigned to a video stream from network device S 1 . TXOP 60 may be a contention period during which any network device may transmit.
[0019] After MAP 40 has been sent to all synchronous network devices, each network device may recognize the particular TXOP that has been assigned to it according to MAP 40 , and either may utilize the TXOP or may pass on it. Carrier sensors within each network device may sense if the network medium is available. If it is free to use, the network device may begin to transmit data.
[0020] Once a non-telephone network device NT has a timeslot assigned to it, it may transmit during its timeslot. For example, timeslot 50 may be assigned to a non-telephone network device NT. If an asynchronous network device, such as asynchronous network device A 1 , begins transmitting before timeslot 50 , or if the asynchronous network device A 1 interrupted at some other time during the cycle of MAP 40 , non-telephone network device NT may shift its start time, as per the HPNA v.3 rules for handling interferences.
[0021] Reference is now made to FIGS. 3A and 3B , which illustrate two transmission scenarios with the same MAP 70 . In FIG. 3A , non-telephone network device NT 1 successfully transmits during a contention period 3 and in FIG. 3B , non-telephone network device NT 1 collides with a telephone network device, such as network device S 2 during contention period 3 .
[0022] MAP 70 comprises 5 timeslots 1 - 5 where timeslot 1 is assigned to network device S 1 , timeslot 2 is assigned to network device S 2 , timeslot 3 is a contention period, timeslot 4 is assigned to network device S 3 and timeslot 5 is another contention period. In FIG. 3A , network devices S 1 and S 2 successfully transmit during their timeslots. Device S 2 does not utilize its entire timeslot and asynchronous network device A 1 takes over the medium once network device S 2 finishes transmitting. Non-telephone network device NT 1 waits for asynchronous network device A 1 to finish, after which, non-telephone network device NT 1 begins its transmission. Non-telephone network device NT 1 , which knows the boundaries of the timeslots, ends its transmission at the end of contention period 3 . Device S 3 then transmits during its timeslot 4 and asynchronous network device A 1 transmits thereafter and into contention period 5 .
[0023] Since no network device collided with non-telephone network device NT 1 , the master network device (which may be any of the synchronous network devices S 1 -S 3 ), received the allocation request from non-telephone network device NT 1 . In the next MAP, MAP 72 , the master network device has allocated a timeslot, timeslot 5 , to non-telephone network device NT 1 and has shifted the second contention period to timeslot 6 . From MAP 72 , non-telephone network device NT 1 may determine that its transmission did not collide with another transmission.
[0024] Non-telephone network device NT 1 may transmit during its assigned timeslot without concern of interruption.
[0025] In the scenario of FIG. 3B , MAP 70 is the same as for FIG. 3A . Synchronous network devices S 1 and S 2 successfully transmit. Once again, device S 2 does not utilize its entire timeslot and asynchronous network device A 1 takes over the medium once network device S 2 finishes transmitting. Non-telephone network device NT 1 waits for asynchronous network device A 1 to finish, after which, non-telephone network device NT 1 begins its transmission during contention period 3 . Unfortunately, at the same time, synchronous device S 2 also begins transmission. Both devices, being synchronous, end transmission at the end of contention period 3 . Synchronous device S 3 utilizes its timeslot 4 , after asynchronous network device A 1 takes the medium.
[0026] Since non-telephone network device NT 1 does not have collision detection abilities, it cannot determine that its transmission was interrupted. However, when the master transmits the next MAP, MAP 72 , there may be no timeslot allocated to non-telephone network device NT 1 . Thus, non-telephone network device NT 1 may determine that its transmission was not successfully received. Non-telephone network device NT 1 may attempt to retransmit during the next available multiple device timeslot.
[0027] Unfortunately, if the contention periods are utilized by the synchronous and asynchronous devices for significant transmission, non-telephone network devices NT 1 and NT 2 may interrupt them as they attempt to register with the master.
[0028] In an alternative embodiment, shown herein in FIG. 4 to which reference is now made, the master may provide a registration timeslot REG for non-telephone network devices NTk. In this embodiment, non-telephone network devices NTk may utilize registration timeslot REG to request timeslots and to change timeslot allocations. Since registration timeslot REG is allocated only to non-telephone network devices NTk, there is less chance of such devices accidentally interfering with telephone devices Si or Aj. They might interfere with other non-telephone devices, in which case, there may be a statistical back off, such as is found in the Ethernet network protocol. Registration timeslot REG may keep the non-telephone devices NTk from interfering with an existing network operation.
[0029] In FIG. 4 , registration timeslot REG is shown as timeslot 3 , just before a contention period in timeslot 4 . Since registration timeslot REG is for non-telephone network devices NTk, contention period 4 may be utilized by synchronous devices Si and asynchronous devices Aj.
[0030] Reference is now made to FIG. 5 , which illustrates one embodiment of the present invention. In this embodiment, the non-telephone wiring is coax or cable television wiring. The home having the HPNA network may have a telephone line 80 , to which synchronous devices S 1 and possibly asynchronous network devices, as well as telephones 81 , may be attached. The synchronous and asynchronous network devices may also be connected to data devices, such as computers, printers, MP 3 players, data servers, etc. Telephones 81 may be connected to the phone line via a connector 83 .
[0031] The home may also have a satellite 82 which may provide satellite TV signals. Satellite 82 may be connected, through coax wiring 84 , to televisions 86 and private video recorders (PVRs) 87 . Coax wiring 84 and telephone wiring 80 may be combined through a combiner 88 , such as the HCT- 3 or HCT- 4 , commercially available from CommunicationsEquip.com, after which there may be a splitter 90 , such as the 1 to 4 splitters commercially available from ABCCables.com, to provide coax wiring 84 separately to multiple televisions 86 and PVR 87 . Splitter 90 may be a known device, used when cabling a home or subscriber premises, to provide coax signals to multiple devices. Splitter 90 may have a high “out to out” isolation, meaning that the signal passing between 2 outputs will be attenuated by more than 20 dB. The isolation may serve to keep the reflected signals from one television 86 or other termination point in the coax network from interfering with other termination points.
[0032] To overcome the high out-to-out isolation of splitter 90 and any attenuation caused by combiner 88 , non-telephone network devices NTk, connected between splitter 90 and the coax termination points, may have a power level higher than that of synchronous network devices Si and/or of asynchronous network devices Aj. The power level may be such that the power on telephone wiring 80 due to non-telephone devices NTk may not exceed the power levels allowable on telephone wiring 80 . Moreover, non-telephone network devices NTk may also have a sensitivity level adjusted to match the higher power level.
[0033] For example, if splitter 90 has an attenuation of 7 dB and combiner 88 has an attenuation of 2 dB, then they have a combined attenuation of about 9 dB. In accordance with a preferred embodiment of the present invention, non-telephone network devices NTk may have a power level set to +9 dB to compensate for the attenuation generated by the bridging between the splitter 90 and combiner 88 . Furthermore, non-telephone network devices NTk may also have a sensitivity set to 9 dB more than that of synchronous network devices Si and/or asynchronous network devices Aj. If synchronous network devices Si have a power level of −7 dBm and a sensitivity level 36 dB below signal level (i.e. −43 dBm), then the sensitivity of non-telephone network devices NTk may be set to 45 dB.
[0034] In an alternative embodiment, the combined attenuation may be 6 dB and the non-telephone network devices NTk may have a power level set to +6 dB. In this embodiment, non-telephone network devices NTk may also have a sensitivity set to 6 dB more than that of synchronous network devices Si and/or asynchronous network devices Aj.
[0035] Reference is now made to FIG. 6 , which details non-telephone network device NT. In this embodiment, device NT may separate data network signals from broadcast network signals, providing the broadcast network signals to the coax end units (television 86 or PVR 87 ) and providing the data network signals to a HPNA coax modem 96 .
[0036] Non-telephone network device NT may comprise a diplexer 91 , comprising a high pass filter (HPF) 92 and a low pass filter (LPF) 94 , and a coax HPNA modem 96 . HPF 92 may be connected between a coax input connector 98 and a coax output connector 100 and may filter out the data network signals. Thus, HPF 92 may pass the frequencies above those of the HPNA network. For example, the HPNA network may operate in the range 4-28 MHz while cable and satellite networks may operate above 50 MHz. LPF 94 may be connected in parallel between coax input connector 98 and modem 96 and may filter out cable or satellite broadcast signals.
[0037] HPNA coax modem 96 may operate according to the principles discussed hereinabove. Thus, it may follow the HPNA v.3 standard with the exceptions that it may not perform collision detection, it may have a power level above that defined in HPNA v.3 and it may have a higher sensitivity level above that defined in HPNA v.3. If the master provides a registration timeslot, modem 96 may utilize the registration timeslot for communicating with the master.
[0038] It will be appreciated that FIG. 6 illustrates one embodiment of a non-telephone network device NT for coax wiring. For other types of connections, such as power line wiring or wireless systems, non-telephone device NT may have some similar elements. For example, there may be elements handling the connection to the network and removing any unwanted signals.
[0039] While certain features of the invention have been illustrated and described herein, many modifications, substitutions, changes, and equivalents will now occur to those of ordinary skill in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. | A hybrid network includes telephone and non-telephone network media. The communication devices communicate along the hybrid network according to a media access plan. The non-telephone communication devices do not have collision detection although the telephone communication devices do. The non-telephone communication devices have higher power and sensitivity levels than the telephone communication devices. In some embodiments, the media access plan includes a registration timeslot for the non-telephone communication devices. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an article having a target part for securing portions together and to a method for manufacturing the target part.
2. Description of the Background Art
A representative example of the article having a target part for securing portions together is a disposable diaper. A securing system of this type consists of a tab having an adhering face and a target part to which the tab adheres to allow the diaper to be put on easily and removed. The target part is usually located at an outer face of the front side of a diaper. Several tabs are arranged at both sides of the inner face of the diaper are able to adhere to and be removed from the target part. The diaper is put on the lower torso of a person's body, adjusted for comfort, then fixed and used. When the diaper is removed, the fastening system is released. Because the surface of the base material of the target part is prepared to satisfy such properties as water-nonpermeability, flexibility, and fashion/appearance, the surface is not suitable for repeatedly attaching and removing the tab to the target part.
The target part, for example as shown in FIG. 4, is made by attaching a resin sheet 202 on a base 200 by means of an adhering agent 201. FIG. 5 shows one example of a process for forming the target part. A continuously supplied oriented polypropylene film 27 is continuously coated with a hot melt adhesive 28 stored at 28, from a coating gun 29, to the whole of a rear face of the film 27. This film is cut to a proper size and attached to a surface of polyethylene film 20, becoming the outer layer of the polyethylene film 20. Thus, the target part is formed on the outer layer of the polyethylene film 20. Another method for forming the target part is to purchase an adhering tape with a surface that has been subjected to mold-releasing treatment (on the back of which a release paper is stuck), and attaching the tape to the outer face of the polyethylene film.
In the forementioned conventional procedure, the material cost for making the target part may be high. The process for making it may also be complex and, therefore, hence the total cost is usually high.
SUMMARY OF THE INVENTION
Accordingly, the first object of the present invention is to provide an article with a target part for securing portions of the article and that reduces the total cost.
Another object is to provide a method for continuously producing such an article.
To solve the first object, an article of the present invention having a target part for repeatably attaching and removing to the adhering face of the tab is characterized by forming the target part from a hot melt resin composition.
To solve the second object, a method is provided for continuously producing such an article, which during processing has a continuously moving base surface, characterized by directly coating this hot melt resin composition on the continuously moving base surface.
A system is thus provided for securing portions of an article, comprising:
a target part formed on a portion of said article; and
a tab formed on another portion of said article;
wherein said tab attaches to said target area to form an impermanent adhesion which is capable of being reestablished if undone; and
said target part is a discernable pattern formed from a hot melt resin composition.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a cross-sectional view showing a target part in an article incorporating the present invention.
FIG. 2 is a schematic illustration of how one preferred method may be used to produce an article, according to the present invention, which has a target part for adhering.
FIG. 3 is a schematic illustration showing a portion of the apparatus shown in FIG. 2.
FIG. 4 is a cross-sectional view illustrating how a known target part is formed.
FIG. 5 is a schematic illustration showing a process for making a previous target part.
FIG. 6 is a plan view showing a disposable diaper incorporating the present invention.
FIGS. 7-13, respectively, show pattern examples of the target part for adhering.
FIG. 14 is a schematic illustration of another embodiment of the apparatus shown in FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
It is preferred that the hot melt resin composition used in the present invention should satisfy all the following conditions of 1 to 4.
1. The open time is short. Although, the shorter the open time the better, it is preferable to have an open time of 0.5 seconds or less. If the open time is longer than this range, the problem of adhesive-attaching to a press roll will occur. 2. The surface energy of the solidified matter is low. The preferred range of surface energy is from about 15 to 25 dyne/cm 2 , for the facility in adhering the target part with the adhering face of a tab to be compatible with the facility in peeling it off. If the surface energy is greater than this range, the mold-releasing character is diminished and the tab release becomes difficult. If less than this range the tab will not adhere.
3. The adhering characteristic with a base material must be excellent. It is required that the peeling-off takes place at an interface between the tab and the target part, not at the interface between the target part and the base material.
4. A preferred blocking character would be one that ensures that the target part is not peeled off, due to attaching to other matter in a period of time between the target formation and practical use. It is also preferred that this blocking character is exhibited at about 65° C. or less.
The hot melt resin composition is prepared so as to be satisfactory for all the above-mentioned conditions by combining, in a suitable proportion, a base polymer, a tackifier resin, wax, oil, pigment, and an antioxidant.
The base resin that is used can be one or a combination of two or more of the following thermoplastic resins: a copolymer of ethylene-vinyl acetate (EVA), polystyrene-polybutadiene-polystyrene block copolymer (SBS), polystyrene-polyisoprene-polystyrene block copolymer (SIS), polystyrene-polyethylene/polybutylene-polystyrene block copolymer (SEBS), or a polyolefin-based polymer.
The tackifier resin that is used can be one or a combination of two or more of the following: an aliphatic or alicyclic hydrocarbon resins, rosin and its derivative, or a terpene-based resin.
The wax that is preferably used is a microcrystalline Fischer-Tropsch wax manufactured solely by Sasol Chemical Industries, Inc., of the Union of South Africa.
The oil that is used can be one or a combination of the following oils: paraffin-based oil or naphthene-based oil.
Additionally, if the hot melt resin composition is used in a visible place, an appropriate pigment may be added to achieve a desired color.
Among the above components, the base polymer, tackifier resin, wax, and oil are used, for example, in the following proportion. Against 100 parts by weight of a total of these four components, the base polymer is from about 20 to 40 parts by weight, the tackifier resin from about 20 to 40 parts by weight, the wax from about 30 to 50 parts by weight, and the oil from about 0 to 20 parts by weight. If an antioxidant is to be used, it is preferred to use it in a proportion of 1.0 part or less by weight against the aforementioned 100 parts. If a pigment for coloring is to be used, it is preferred to use it in a proportion of 1.0 part by weight against the aforementioned 100 parts.
Furthermore, according to the present invention, since the target part is made by a hot melt resin composition, various properties can be achieved by properly designing the hot melt resin composition. For example, the properties of adjustment of flexibility, reinforcement of a base material, and control of a peel strength, can be determined, for example, by controlling the amount of a rubber-based polymer used, by the use of a resin that has a high softening point, or by using a different combination of waxes.
A hot melt resin composition prepared with the above-described components is directly coated on a base material surface. This coating is carried out by using a common hot melt coating gun. The coating thickness may be similar to that of a common hot melt adhesive, for example, in an order of from about 50 to 200 μm. Also, since the target part is made by coating the hot melt resin composition directly onto the base, the target part can be easily formed on a continuously moving base material. Furthermore, since there is no need to lower line speed to cut the adhesive tape and the like, it is possible to increase line speed.
A mark is used to indicate the placement of the tab on the target area for a comfortable fit of the diaper. The next time a diaper is to be used, the tab can be placed directly on the target area, as indicated by the mark. Having previously determined the placement of the tab, the mark prevents having to adjust the diaper to achieve a comfortable fit each time it is used.
Where a hot melt resin composition completely coats the portion of the base material which is to become the target part, a mark indicating tab placement can be printed beforehand. The printed mark will be seen through the hot melt resin composition.
Alternatively, the mark can be drawn by a hot melt resin composition when this composition is formed. This is called screen coating. In screen coating, a screen having many small holes is used to depict the desired pattern. A hot melt resin composition is pushed through the holes onto the base, with the resulting coating formed from many small dots. Thus, the coated pattern also serves as a mark to show the position for the placement of the tab. It is possible to make various designs from the assembly of dots. By changing the pattern shape and/or the dot size, the peel strength required to remove an attached tab can be adjusted without any change in the components and combination of the hot melt resin composition.
The base material for the target part is a combination of a polyethylene film and an OPP (oriented polypropylene) film for a disposable diaper.
Article having a target part for adhering, as produced by the present invention, include a disposable diaper and a drape for medical use, but the possibilities are not limited to those described here.
The "tab" is defined in an article having a target part, as a part being arranged in another portion of the same article and having an adhering face to attach to the target part. For example, when a portion of an adhesive tape is attached to an article and the remaining portion is unattached, this unattached portion is called a tab. Furthermore, when the adhesive character of the tab is not to be used, release paper covers the tab to maintain the adhesive character of the tab. The release paper then can be peeled off to adhere the tab with the target part.
By making the target part from a hot melt resin composition, it is unnecessary to use a resin sheet which converts into the target part, resulting in decrease in the material cost and a simplification of the process. In addition, conventional continuous production line can be used.
Hereinafter, the present invention is explained in detail, referring to figures which show examples of the invention, but the present invention is not limited by the examples and figures.
FIG. 1 is a cross-sectional view showing an example of an article having a target part for adhering, relating to the present invention. As seen in FIG. 1, this article 100 has a target part 102 made from a hot melt resin composition on a surface of the base material 101 and, when compared with a conventional target part shown in FIG. 4, the present invention is simplified because it lacks the resin sheet 202. Such an article 100 may be produced by either a continuous production method or a noncontinuous production method.
FIG. 2 shows the present invention being incorporated into a method for producing a disposable diaper. As seen in this figure, a tissue paper 2 is continuously supplied from a first roll 1 and a second tissue paper 32 is continuously supplied from a second roll 31, and a water-absorbent material 3 is placed between these tissue paper layers 2 and 32. A polyethylene film 20, which forms the back sheet, is continuously supplied from roll 21. As seen in FIG. 3, a hot melt resin composition from a source 25 thereof is coated, in a necessary amount, on the polyethylene film 20 by the coating gun 26 (as shown by 24 in FIG. 3), forming a patterned target part (not shown in the figure) on an outer surface of the polyethylene film 20. The hot melt resin is pressed to the polyethylene film by passage over a pressure roll 30 (best seen in FIG. 3). This hot melt resin composition 25 is as described above.
On the rear side of the polyethylene film 20, having the formed target, a hot melt adhesive is continuously applied from the coating guns 19 and 23. The film 20 is attached to the tissue paper 2 by the adhesive so that it greatly overhangs the tissue paper 2. An elastic band 9 is attached by the adhesive to form a stretching and shrinking part on both sides of the water-absorbent material 3. A non-woven fabric 4, continuously supplied from the roll 5, is attached to tissue paper 32 by the adhesive continuously supplied from coating gun 6 so that it greatly overhangs tissue paper 32.
Thus, a layered article is produced that comprises a combination of tissue paper 2, water-absorbent material 3, and tissue paper 32 that is placed between the polyethylene film 20 and the non-woven fabric 4. This article is cut to form a disposable diaper. Although formation of a tab having an adhering face has not been mentioned, it is carried out in the usual way.
FIG. 6 shows a plan view of an example in a case where the article in the present invention is a disposable diaper. The diaper 110 is shaped similar to the letter "I", and comprises lower abdomen part 110a with two wings stretched to the left and right, the crotch part 110b constricted at the central part, and the hip portion 110c having two wings stretched to the left and right. In an area that extends from the lower abdomen 110a to the hip portion 110c, absorbent material 3 is placed between two tissue papers, so that urine, etc. is absorbed and held. On the left and right sides of the absorbent material 3, an elastic band 9 is arranged so that a contracting force operates to keep the diaper 110 in firm contact around the groin of the wearer. The tabs 103 are set at the pointed ends of two wings of the hip portion 110c. On a surface of a base material (for example, a polyethylene film) of the lower abdomen part 110a, the target parts 102 for adhering are formed of a hot melt resin composition as described above.
A mark that is on a surface of the base material 101 on a lower side of the target part for adhering 102, printed to indicate a tab-sticking position, will be seen through the hot melt resin composition. On the other hand, the mark may be drawn with the hot melt resin composition when the target part 102 is formed.
FIGS. 7-13 show sample patterns for marks on the left and right target parts 102. When the disposable diaper 110 is made, each of A and B in FIGS. 7-13 are respectively placed on the right lower abdomen and left lower abdomen. As the tab shown in FIGS. 7-13 is attached toward the center, the diaper becomes tighter, and as it is attached toward the outside, the diaper becomes looser. If the same disposable diaper is to be repeatedly used by the same wearer, once a comfortable fit for the diaper is determined the next diaper can be attached at the same mark for the same fit.
FIG. 14 depicts the process for a target part for adhering that is made by a screen printing of the hot melt resin composition. In place of the coating gun 26 shown in FIG. 3, there is used a cylinder type screen 260 that is arranged so as to rotate around the center axis. When the hot melt resin composition 25 is placed in the cylinder type screen 260 and is rotated, the hot melt resin composition 25 is pressed to the inner circumferencial face by a doctor blade 261, and passes through transmission holes to the outside. Thus, the hot melt resin composition 25 is coated on a surface of the base material polyethylene film 20, to form the target part. The coating pattern of the hot melt resin composition 25 is, as shown in FIGS. 7-13, for example.
The cylinder type screen 260 is designed so that one circumference length corresponds to the length of the disposable diaper 110, and the transmission holes are arranged, for example in a pattern shown in FIGS. 7-13, in a part of a circular arc as long as the target part. Thus, screen printing can be carried out by rotating the screen 260 in correspondence with the velocity of a disposable diaper-producing line, and a process for making the target part for adhering 102 can be included in the disposable diaper-producing line. A different method for integrating screen printing into the disposable diaper production line may also be used.
Hereinafter, practical examples and comparative examples of the present invention are described but this invention is not limited to the discussed examples.
EXAMPLE 1
The hot melt resin composition used for making the target part for adhering depicted in FIG. 2 had the following composition:
base polymer: EVA (EV-220, made by Mitsui Dupont Polychemical Co., Ltd.) - - - 33 parts by weight
tackifier resin: C 9 -based hydrogenated petroleum resin (Akron M115, made by Arakawa Chemical Industries, Ltd.) - - - 22 parts by weight
wax: microcrystalline wax (Sasol H 1, made by Sasol Chemical Industries, Ltd.) - - - 45 parts by weight
antioxidant (age resistor): (Irganox 1010, made by Ciba-Geigy Japan, Ltd.) - - - 0.4 parts by weight
These components were well mixed in a melting step at 140° C., and coated at a thickness of 150 μm on a polyethylene film of thickness 40 μm, to form a target part.
EXAMPLE 2
The procedure of example 1 was repeated except that the hot melt resin composition was changed to the combination described below.
The hot melt resin composition was:
base polymer: SIS (SL-102, made by Nippon Zeon Co., Ltd.) - - - 22 parts by weight
tackifier resin: hydrogenated petroleum resin (Escorez 5300, made by Tonex Co., Ltd) - - - 25 parts by weight
oil: paraffin-based oil (PW-90, made by Idemitsu Kosan Co., Ltd.) - - - 10 parts by weight
wax: microcrystalline wax (Sasol H 1, made by Sasol Chemical Industries, Ltd.) - - - 43 parts by weight
antioxidant (age resister): (Irganox 1010, made by Ciba-Geigy Japan, Ltd.) - - - 0.4 parts by weight
ultraviolet rays absorbent (JF-77, made by Johoku Chemical Co., Ltd.) - - - 0.2 parts by weight
EXAMPLE 3
The procedure of example 1 was repeated except that the hot melt resin composition was changed to the combination described below.
The hot melt resin composition was:
base polymer: SBS (Tufprene 315, made by Asahi Chemical Industry Co., Ltd.) - - - 25 parts by weight
tackifier resin: hydrogenated petroleum resin (Admarv S-100, made by Idemitsu Petrochemical Co., Ltd.) - - - 25 parts by weight
oil: paraffin-based oil (PW-90, made by Idemitsu Kosan Co., Ltd.) - - - 5 parts by weight
wax: microcrystalline wax (Sasol H1, made by Sasol Chemical Industries, Ltd.) - - - 45 parts by weight
antioxidant (age resister): (Irganox 1010, made by Ciba-Geigy Japan, Ltd.) - - - 0.4 parts by weight
ultraviolet rays absorbent (JF-77, made by Johoku Chemical Co., Ltd.) - - - 0.2 parts by weight
EXAMPLE 4
The procedure of example 1 was repeated except that the hot melt resin composition was coated in a pattern shown in FIG. 11 (refer to FIG. 14) under the conditions of a coating temperature (a screen temperature) of 110° C., a coating amount of 50 g/m 2 , and a web speed of 100 m/minute, and using a screen printing machine (Micro Print, made by LTI GRACO Co., Ltd.).
For the disposable diapers in the above examples 1-4, the undermentioned properties of from (1) to (5) were investigated. Results are shown in Table 1.
(1) Surface energy.
It was investigated by a method of measuring a contact angle of a solid.
(2) Adhering property with tab (or fastening tape).
The peel strength between the tab (for commercial articles, their respective fastening tape and, for the examples, a commercially-available adhesive tape, made by 3M Co., Ltd.) and the target part was investigated.
(3) Refastening property.
Similary to (2), the tab and a target part were repeatedly attached and removed. The fifth time was used for measurement of the peel strength.
(4) Open time.
In a pilot line which shows the whole of FIG. 3, a hot melt resin composition was melted at 140° C. and coated on a polyethylene film having a thickness of 40 μm in a coating thickness of 150 μm, on which a paper of fine quality was stuck. The coating was carried out with a varied line speed, then the period of time from the coating to the sticking of the paper was varied in a range of 0.1 to 1.0 second, and the longest time required for adhesion was assigned as the open time.
(5) Blocking property.
A sample was prepared by coating the hot melt resin composition of each example on a polyethylene film and, on a resin composition side of the sample, a polyethylene film was piled up. The sample stood for 24 hours in an oven at 60° C. Whether or not the piled polyethylene film and the resin composition stuck together upon examination is indicated by a cross X if it is sticking and by a circle O if it is not sticking.
For comparison to the examples of the present invention, the target tape parts of the under-described commercially-available disposable diapers were taken by cutting and subjected to examination of the above-described 1-5 properties. Results are shown in Table 1.
Comparative example 1 - - - Pampers of Proctor & Gamble Far East, Inc.
Comparative example 2 - - - Ultra Mooney of Uni-Charm Corporation.
Comparative example 3 - - - Merries of Kao Corporation.
TABLE 1__________________________________________________________________________ Example Example Example Example Comparative Comparative Comparative 1 2 3 4 example 1 example 2 example 3__________________________________________________________________________Surface energy 19.5 19.1 22.7 19.7 20.3 23.5 20.5(unit: dyne/cm)Adhering property 460 430 450 480 420 440 400with tab(unit: gf/25 mm)Refastening property 400 410 420 440 470 420 400(unit: gf/25 mm)Open time 0.2 0.2 0.2 0.2 -- -- --(unit: second) or less or less or less or lessBlocking property ∘ ∘ ∘ ∘ -- -- --__________________________________________________________________________
As seen in these results, the examples of the present invention exhibited of no problems and the target parts were formed with less materials and by a simpler process than those for commercially-available articles.
It will be readily seen by one of ordinary skill in the art that the present invention fulfills all of the objects set forth above. After reading the foregoing specification, one of ordinary skill will be able to effect various changes, substitutions of equivalents and various other aspects of the invention as broadly disclosed herein. It is therefore intended that the protection granted hereon be limited only by the definition contained in the appended claims and equivalents thereof. | An article having a target part for adhering, wherein the part adheres with an adhering face of a tab in a repeatedly releasable manner in which the target part is made of a hot melt resin composition. Thus, the total cost for making the target part is reduced. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is the national phase under 35 U.S.C. § 371 of PCT International Application No. PCT/SE00/00130 which has an International filing date of Jan. 21, 2000, which designated the United States of America and was published in English.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a removable core cylinder lock, comprising a cylinder lock casing having a casing wall defining an axially extending cavity with an insertion opening, a removable cylinder lock core which has an outer contour corresponding to the inner contour of said cavity and which is axially insertable into the cavity through the insertion opening. The lock core has an upper, substantially massive part with a row of holes for accommodating locking tumblers, and a lower part defining a cylindrical bore extending therethrough. A cylindrical, rotatable key plug is located in the cylindrical bore and has a longitudinal key slot for receiving a key co-operating with the locking tumblers, a retainer adapted to releasably retain the lock core in an inserted position in the cavity in the lock casing, and mutually fitting parts in the rear, axially inner portions of the casing and the lock core, including projections at the rear end portion of the casing and corresponding recesses at the rear end portion of the lock core.
2. Description of Related Prior Art
Such locks are previously known from commercial embodiments offered on the market by the Best Lock Company. In these embodiments, the projection at the rear end portion of the casing comprises a pair of relatively narrow pins on a rotatable locking member, whereas the corresponding recess comprises a corresponding pair of axial bores in the key plug.
However, in such a lock, including a casing and a lock core, it is quite possible to replace a lock core of a first kind by a lock core of a second kind provided that the replacing lock core has the same or a narrower outer contour and similar axial bores in the key plug.
OBJECTS AND SUMMARY OF THE INVENTION
The object of the present invention is to further develop such a lock so as to prevent such replacement of the lock core, or at least make such replacement more difficult.
According to the present invention, this object is achieved in that the projections of the casing comprise two lugs extending radially inwards from the casing wall on each side of a central vertical plane of the casing, in that the corresponding recesses comprise two recesses located in the massive part on both sides of a central rear portion containing the row of holes, the two recesses being dimensioned to accommodate two lugs, so as to permit full insertion of the lock core into the casing, and in that the two lugs are each provided with means for fastening the casing to an object.
With such a structure, a similar lock core with exactly the same outer contour and the same length cannot be inserted into the casing unless it is provided with the same kind of recesses at its rear portion. It is a very difficult matter to measure the dimension of the lugs at the innermost end of the casing and to make a corresponding recess in the lock core.
The two lugs are separated transversely from each other so as to leave a central passage therebetween. The central rear portion of the removable core fits into this central passage.
Also, the lugs at the rear portion of the casing are used to provide means for fastening the casing to an object, such as a door or the like. Thus, the fastening means are concealed behind the lock core itself, and it will be difficult to reach the fastening means from the outside by drilling or similar operations.
The lugs and the recesses should have a substantially supplementary configuration. Preferably, each lug is defined by a concave cylindrically curved surface, whereas the lug has a corresponding convex cylindrically curved surface.
Accordingly, the structural features of the casing and the lock core will enable easy insertion of a correctly designed lock core into the casing, whereas a similar lock core, having the same outer contour, the same length but no corresponding recess of the specific kind and dimensions, cannot be inserted into the casing. Moreover, it is difficult to provide such a recess in the similar lock core by straight forward machining operations. Therefore, the removable core cylinder lock according to the invention has a high degree of security against unauthorized manipulation of the lock by replacement of the lock core with a less secure lock core of another kind.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
FIG. 1 shows in a perspective view a door lock assembly with two lock casings and a removable lock core to be inserted into one of the casings;
FIG. 2 shows, in perspective view, the lock core of FIG. 1 (without key plug and retainer member);
FIG. 3 shows, likewise in perspective view, a retainer member and a key plug (taken out from the lock core in FIG. 1 );
FIG. 4 shows the lock core of FIG. 1 as seen from the rear end (indicated by the line IV—IV in FIG. 1 );
FIG. 5 shows the two casings in FIG. 1 in a perspective view from the front (from the right hand side);
FIG. 6 shows the lock core in FIG. 1 in perspective view from the rear; and
FIG. 7 is a cross-section through the casing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 there is shown a door lock assembly with two lock casings, viz. a rear casing 10 r to be mounted at the inside of a door (not shown), and a front casing 10 to be mounted at the front side of the door, and a removable lock core 20 which is insertable into the casing 10 . A lock core of the same kind as the lock core 20 can be inserted into the rear casing 10 r . Alternatively, a door knob or like mechanism can be mounted in the casing 10 r at the inside of the door. On both the rear and front sides, a rotary member 11 r and 11 , respectively, is mounted so as to transfer a rotary movement from the door knob and a key plug of the lock core 20 , respectively, to a door lock mechanism (not shown) disposed between the casings 10 r and 10 .
The lock core 20 shown in FIGS. 1, 2 and 6 has the general cross-sectional configuration of the digit “8” and fits with a certain play in a corresponding cavity 12 in the casing 10 . The core 20 has an upper, substantially massive part 21 and a lower part 22 with an interior cylindrical bore 23 for accommodating a rotatable key plug 30 (FIG. 3 ). In the rear part of the lock core 20 , there is a slot 25 approximately in the region between the upper and lower parts 21 , 22 of the core. The slot is open at the rear end (compare FIG. 2) and extends along the core 20 somewhat longer than half the length thereof.
In this rear portion of the lock core 20 , there is an adjoining chamber 26 (FIG. 4 ), in which there is journalled a retainer member 40 (FIG. 3 ). The latter is movable in the chamber 26 between a releasing position (as shown in FIG. 1) and a locking position. In the locking position, it engages with a locking projection 13 (FIGS. 1 and 5) inside the cavity 12 of the casing 10 so that it is retained in the casing and also holds the lock core 20 and the key plug 30 in inserted positions inside the cavity 12 .
As is known in the art, the key plug 30 has a longitudinal key slot 31 (FIG. 4) with a front opening 32 (FIG. 3) and a row of six holes 33 . The holes 33 are located in line with a row of six corresponding holes 34 in the lock core 20 , when the key plug is oriented in its releasing position (as shown in FIGS. 2 and 3 ). In each pair of corresponding holes 33 , 34 , there are upper and lower tumbler pins 36 , 37 , which are biased downwards by helical springs 38 (FIG. 2 ). The tumbler pins cooperate with the upper edge of a key inserted into the key slot 31 .
The door lock assembly described so far is of the general kind described in WO 96/36782 (WINLOC AG) and the Swedish patent application filed concurrently by the same applicant (WINLOC AG).
In accordance with the present invention, the casing 10 and the lock core 20 have mutually fitting projections and recesses which ensure that the lock core 20 cannot be replaced by another lock core having the same contour and length unless it is provided with exactly the same recesses.
As appears from FIGS. 5 and 7, the casing 10 is provided, at its rear end portion, with two lugs 14 , 15 , which are formed in one piece with the casing 10 and extend radially inwards from the upper cylindrical wall surface 12 a of the cavity 12 . Each lug 14 , 15 is approximately triangular with a beveled or rounded edge 14 b , 15 b between two substantially planar, mutually perpendicular surface portions 14 a , 14 c and 15 a , 15 c , respectively. In the axial direction, the lugs 14 , 15 extend from a rear end wall 17 (FIGS. 1 and 7) along a length corresponding approximately to 0.1-0.4 of the total length of the casing 10 . The end wall 17 has a lower circular opening 18 , in which the rotary member 11 is mounted (see also FIGS. 1 and 5 ).
In a cross-sectional view (FIG. 7 ), the length of the sides 14 a , 14 c , 15 a , 15 c of the lugs 14 , 15 is about 0.2-0.4 times the diameter of the cylindrical upper portion 12 a of the cavity, and the distance between the parallel side surfaces 14 c , 15 c of the lugs is therefore at least 0.2 times the last mentioned diameter. Accordingly, the lugs 14 , 15 define a central passage 16 between the side surfaces 14 c , 15 c.
In each lug 14 , 15 there is an axial hole 14 h , 15 h near the cavity wall 12 a . These holes 14 h , 15 h serve to provide screw fasteners for fastening the casings 10 , 10 r to each other (or to some other part of the door or the like). A fastening screw 1 with a head 1 a can be inserted from either side, i.e. from the inside of the door, as indicated in FIG. 1, or from the outside of the door (not shown), or one screw from each side, as shown in FIG. 5 . The screws can engage with internal threads in the holes 14 h , 15 h (as shown) or with corresponding nuts (not shown). In order to make room for the screw head 1 a , an extra recess 12 b is formed in the cavity wall 12 a adjacent to the respective hole 14 h , 15 h.
In the preferred embodiment of the invention, the lock core 20 is provided with two recesses 27 , 28 at the rear end portion, as appears from FIGS. 1, 2 , 4 and 6 . The recesses 27 , 28 are concavely curved with a curvature corresponding to the two lugs 14 , 15 , so as to leave a central rear portion 29 in which two of the holes 34 are located. This rear portion 29 has a length which corresponds to the axial dimension of the lugs 14 , 15 . Thus, the rear portion 29 can be fitted snugly into the central passage 16 of the casing 10 when the lock core 20 is inserted therein. On the other hand, any other lock core, without such recesses, cannot be inserted into the casing 10 .
Of course, the exact geometrical configuration of the lugs 14 , 15 and the corresponding recesses 27 , 28 can be modified by those skilled in the art.
As illustrated in FIGS. 1, 4 and 5 , there is a further way to prevent insertion of the lock core 20 into the casing 10 , unless the lock core 20 is designed in a specific manner. The rotary member 11 , which is basically cylindrical and journalled for rotation in the rear opening 18 of the casing 10 , is provided with an axially extending rod 2 , which is located eccentrically and is rather wide, in the specific example 3.7 to 4.5 mm. As appears from FIG. 4, the rod 2 is cylindrical (but could have any other suitable cross-sectional shape) and projects into a corresponding, somewhat wider hole 35 (4-5 mm) in the key plug 30 . The hole 35 extends from the rear end surface of the key plug 30 along about half the length of the latter.
The width of the rod 2 and the corresponding hole 35 is such that the interior walls of the hole 35 are located very close to the key slot 31 and the outer circumferential surface of the key plug 30 . In this way, it will be practically impossible to make such a hole in an existing lock core and key plug unit not originally designed to cooperate with the wide rod 2 .
In order to secure a good transfer of the rotary movement from the key plug 30 to the rotary member 11 , the latter is also provided with a short axial lug 3 which has a rectangular cross-section and fits into a corresponding groove at the rear end surface of the key plug 30 . | A removable core cylinder lock, comprising a casing, a lock core with a rotatable key plug in a cylindrical bore and a retainer adapted to releasably retain the lock core in an inserted position in the casing. The casing has two lugs extending radially inwards and being separated transversely from each other, whereas the lock core has two corresponding recesses on both sides of a central, rear portion, whereby the lock core can be fully inserted into the casing. The two lugs are provided with holes accommodating fasteners for fastening the casing to an object. | 4 |
The U.S. Government has rights in this invention pursuant to Contract No. DE-AC06-76FF02170 between the U.S. Department of Energy and Westinghouse Electric Corporation.
BACKGROUND OF THE INVENTION
This invention relates generally to heat exchangers and, more particularly, to a heat exchanger employed in a hostile, radioactive environment.
One of the critical problems encountered in the development of nuclear energy is that substantially all inspection and maintenance of test and operative facilities and the equipment associated therewith must be remotely performed. Even the various fluid flow systems supporting such development must be contained in shielded cells or rooms to protect personnel. For example, in a proposed radiation test facility employing an accelerated deuteron-lithium stripping reaction to generate a high energy neutron source, the liquid lithium circulating or loop system, including the pump, heat exchanger, and various other components, are completely enclosed within a shielded containment. Conventional heat exchangers would pose problems in such an enclosed, hostile environment since the coolant inlet and outlet nozzles form a part of the heat exchanger's bonnet or head and must be uncoupled from their associated pipe connections before the head can be removed from the body of the exchanger. This is an arduous and time consuming task when done by remotely controlled manipulators and seriously impedes maintenance and inspection. Moreover, these uncoupling procedures are further complicated by the limited or restricted space provided in these shielded enclosures.
Accordingly, it is a primary object of the present invention to obviate the above noted shortcomings by providing a new and useful heat exchanger facilitating remote inspection and maintenance thereof.
It is another object of this invention to provide in the foregoing heat exchanger a detachable head affording complete and unrestricted access to all tube ends for inspection and repair.
It is a further object of the present invention to provide in the foregoing heat exchanger a novel tube sheet embodying all tube ends and nozzle connections for facilitating inspection and maintenance thereof.
These and other objects, advantages, and characterizing features of this invention will become clearly apparent from the ensuing detailed description of an illustrative embodiment thereof, taken together with the accompanying drawings wherein like reference characters denote like parts throughout the various views.
SUMMARY OF THE INVENTION
A heat exchanger including a shell having a fluid inlet tube and a fluid outlet tube. The shell is closed at one end and attached at its other end to one side of a tube sheet. A hollow detachable head is connected to the other side of the tube sheet and is provided with a partition separating the head into a first and second chamber. A tube bundle is mounted in said shell and is provided with inlets and outlets in said tube sheet communicating with said first and second chambers, respectively. A nozzle inlet and a nozzle outlet is formed in said tube sheet in fluid communication with said first and second chambers, respectively.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view, partly broken away, of a heat exchanger constructed in accordance with the principles of this invention, showing the head portion and shell in phantom for the sake of clarity; and
FIG. 2 is a longitudinal sectional view, on an enlarged scale and partly broken away, of the heat exchanger shown in FIG. 1, showing only a few of the many tubes incorporated therein.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now in detail to the illustrative embodiment depicted in the accompanying drawings, there is shown in FIG. 1 a heat exchanger, comprehensively designated 10, constructed in accordance with this invention, and forming a part of a liquid lithium flow system (not shown). Liquid lithium is employed in an accelerated deuteron-lithium stripping reaction to generate a high energy neutron source in order to determine the effect of high energy neutrons on certain experimental materials. The lithium is heated to elevated temperatures during such reactions and is subsequently cooled by means of the heat exchanger of this invention. Since the lithium system forms no part of the present invention, it is believed that no further amplification or description thereof is necessary. Also, it should be understood that the heat exchanger of this invention is in no way restricted in use to a lithium circulating system, but has utility in any fluid flow system where it is desired to effect a heat transfer between fluids, and especially in those systems limiting or prohibiting human access.
The heat exchanger 10 comprises an elongated casing or shell 11 closed at one end 12 and welded or otherwise fixedly secured at its other end to a tube sheet 13. The tube sheet 13 is connected to a removable cover or head 15 to form a closed, unitary structure, as shown in phantom in FIG. 1. The unique construction of tube sheet 13 and head 15 together form a significant feature of the present invention as will hereinafter become apparent.
An elongated horizontally extending plate 16 is rigidly attached at its forward end (the left end as viewed in FIG. 1) to the tube sheet 13 and extends rearwardly therefrom toward closed end 12, terminating somewhat inwardly from such closed end 12 in axially spaced relation thereto. The lateral extent of plate 16 approximates the inner diameter of shell 11 with only sufficient clearance between the opposite lateral sides of plate 16 and the shell 11 to permit relative sliding movement therebetween for accommodating differential thermal expansion thereof. The plate 16 is located approximately midway of shell 11 and serves as a barrier, separating the shell 11 into an upper and lower compartment 17 and 18 communicating with each other at the rear end of shell 11. The terms forwardly, rearwardly, horizontally, upper and lower as used herein are applied only for ease of description with reference to FIG. 1, and should not be taken as limiting the scope of this invention, it being understood that the heat exchanger can be oriented in any desired attitude in use.
A plurality of tubes 20, forming a "tube bundle", are mounted within shell 11 and have their inlet ends rigidly secured to tube sheet 13. These tubes 20 form continuations of inlet openings 21 provided in the upper portion of tube sheet 13. The tubes 20 extend rearwardly through upper compartment 17 and are curved 180° adjacent the rear end of shell 11 to then extend forwardly through the lower compartment 18. The tubes 20 terminate in outlet ends rigidly secured to the tube sheet 13 and form continuations with outlet openings 22 provided in the lower portion of tube sheet 13.
The tubes 20 are supported in a series of longitudinally spaced baffles 23 and 25 provided with suitable openings 26 and 27 for receiving the tubes 20 in a fluid-tight relation. The baffles 23 are of partial circular configuration in plan and extend from the shell inner wall surface to approximately midway toward barrier plate 16. These baffles 23 have curved peripheral edges 28 complementary in shape to the internal wall surface of shell 11. However, baffles 23 are constructed in a manner allowing relative sliding movement between edges 28 and shell 11.
The baffles 25 are in the form of elongated segments extending transversely of the shell 11 and provided with inner longitudinal edges 30 in substantial abutment against barrier plate 16 but slidable relative thereto. The outer longitudinal edges 31 of baffles 25 are spaced vertically from the shell inner wall surface. The opposite ends of the baffles 25 are arcuately shaped, as at 32, to conform to the shape of the inner wall surface of shell 11 but can slide relative to the latter. Each pair of baffles 25 are mounted in a common transverse plane on opposite sides of barrier plate 16 and in axially spaced relation from baffles 23, also mounted in pairs in a common transverse plane on opposite sides of plate 16. Thus, baffles 23 and 25 function to support and separate the tubes 20 within shell 11 and also serve to direct the fluid to be cooled in a sinuous path through the compartments 17 and 18. The tubes 20 and baffles 23 and 25, herein referred to as a "tube bundle," are assembled as a unit and, as such, can expand axially relative to shell 11.
The detachable bonnet or head 15 is of generally hemispherical shape and has an integral annular flange 33 formed with a plurality of circumferentially spaced openings 35 adapted to be aligned with tapped openings 36 formed in the outer peripheral portion 37 of tube sheet 13. Suitable bolts 38 can then be inserted through openings 35 and threaded into the tapped openings 36 for firmly, but detachably securing the head 15 onto tube sheet 13. A deformable, metallic seal 39 is interposed between flange 33 and tube sheet portion 37 and is compressible upon tightening bolts 38 to provide pressure sealing therebetween. Since the head 15 is removable and replaceable remotely by manipulators, additional openings (not shown) can be formed in flange 33 to receive corresponding guide pins on tube sheet portion 37 for properly guiding and aligning the head 15 onto the sheet 13 when assembling the same. Also, lifting lugs 42 can be provided on the outer surface of head 15 to facilitate handling by the remotely controlled apparatus for removing and replacing head 15.
An internal partition 43, formed integral with head 15 and located centrally thereof, extends in cantilever fashion from the apex of the inner wall surface of head 15 and is adapted to engage with a flush fit against the front face of tube sheet 13 in the assembled relation therewith as shown in FIG. 2. The partition 43 separates the interior of head 15 into an upper chamber 44 and a lower chamber 45.
An inlet nozzle 46, located exteriorly of shell 11, is connected to the rear side of tube sheet 13 and is provided with an inlet end forming a continuation of an enlarged opening 48 provided in the upper portion of tube sheet 13. Likewise, an outlet nozzle 50, located outwardly of shell 11, is connected to the rear side of tube sheet 13 with its inner end forming a continuation of an enlarged opening 52 in the lower portion of tube sheet 13. With head 15 properly secured to tube sheet 13, communication of flow is established from the inlet nozzle 46 to tubes 20 via enlarged opening 48, upper chamber 44 and inlet openings 21 and from the tube outlets 22 to outlet nozzle 50 via lower chamber 45 and enlarged opening 52.
Shell 11 is provided with an inlet tube 53 in the lower compartment 18 behind tube sheet 13 and an outlet tube 55 in the upper compartment 17, also behind tube sheet 13. The upper chamber 44 of head 15 is provided with a vent nozzle 56 for releasing any gases generated therein and the lower chamber 45 is provided with a drain nozzle 57 permitting complete discharge of any coolant therein prior to removing head 15. These nozzles 56 and 57 are connected via piping to suitable control values (not shown) located exteriorly of the enclosure for opening and blocking flow therethrough, as required.
In operation, an organic coolant is admitted into inlet nozzle 46 and directed, as indicated by arrows A, through upper chamber 44 into the openings 21 and the inlets of tubes 20. The coolant flows via tubes 20 rearwardly through the upper shell compartment 17, about barrier plate 16 and then forwardly through the lower shell compartment 18. The coolant exits the tubes 20 through outlet openings 22 into lower chamber 45 and then is discharged through outlet nozzle 50.
The coolant is cycled through the tube bundle for cooling a liquid, such as high temperature lithium, admitted into the shell 11 by means of inlet tube 53 suitably connected to the liquid lithium flow system. The lithium flows through shell compartment 18 in a sinuous path, as indicated by arrows B, about the baffles 23 and 25 and along the tubes 20 in heat exchange relation to the coolant flowing in a general opposite direction therein. The lithium flows upwardly and about the free end of barrier plate 16 adjacent the closed end 12 of shell 11, through upper shell compartment 17 in a sinuous path in heat exchange relation with the coolant flowing in a general opposite direction in tubes 20 and is then discharged at a reduced temperature through outlet tube 55 for return to the lithium flow system.
When desired or required to inspect or repair the tubes 20 via the tube sheet 13, the head 15 is easily and expediently detached by removing the bolts 38 and removing head 15 from tube sheet 13. This exposes the entire face of the tube sheet 13, including the several tube openings 21 and 22, as well as the coolant inlet and outlet openings 48 and 52, without in any way disturbing the piping connections for the tube side fluid, which may be the coolant as described in the preferred embodiment of this invention, or the fluid to be cooled, if desired. Thus, unrestricted access to all tube end openings is obtained for inspection and repair by remotely controlled manipulators.
The foregoing description of a preferred embodiment of this invention has been presented for purposes of illustration and description only, and it is not intended to be exhaustive or to limit the invention to the precise form disclosed. It was chosen and described in order to best explain the principles of the invention and their practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto | A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of copending International Application No. PCT/DE99/03828, filed Dec. 1, 1999, which designated the United States.
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to an integrated circuit configuration and a method for manufacturing it.
Efforts are generally being made to generate an integrated circuit configuration, i.e. a circuit that is integrated in a substrate, with an ever higher packing density.
German Patent DE 197 27 436 C1 describes a DRAM cell configuration in which a memory cell contains a first transistor, a diode structure and a second transistor. The first transistor and the second transistor share between them a common source/drain region and are connected between a voltage terminal and a bit line. A gate electrode of the second transistor is connected to a word line. The diode structure is connected between a gate electrode of the first transistor and the common source/drain region. The transistors are disposed one over the other and are embodied as vertical MOS transistors. The common source/drain region is disposed in a semiconductor structure at whose edges gate electrodes of the transistors in the form of spacers are disposed. The diode structure is composed of a Schottky diode and a tunnel diode which are connected in series. The tunnel diode is formed by the gate electrode of the first transistor, a dielectric layer, which is disposed on the gate electrode of the first transistor, and by a further conductive spacer, which is separated from the gate electrode of the first transistor by the dielectric layer. The Schottky diode is formed by a conductive structure made of metal silicide, which is disposed on an upper part of the further conductive spacer and adjoins the common source/drain region, and by the conductive spacer.
Published, European Patent Application EP 0 537 203 describes a DRAM cell configuration in which a memory cell contains a planar first transistor, a planar second transistor and a voltage-dependent resistor. The first transistor and the second transistor have a common source/drain region and are connected between a voltage terminal and a bit line. A gate electrode of the first transistor is disposed over a gate dielectric and a metal film is disposed over the common source/drain region. The common source/drain region is connected to the gate electrode of the first transistor via the voltage-dependent resistor. The voltage-dependent resistor is, for example, a Schottky junction and is formed by the gate electrode of the first transistor and the metal film. A gate electrode of the second transistor is connected to a word line. The voltage-dependent resistor does not require any additional space, which contributes to increasing the packing density of the DRAM cell configuration.
U.S. Pat. No. 5,463,234 discloses an integrated circuit configuration in which a Schottky diode is connected between a source/drain and a titanium film which extends over a gate electrode. Between the gate electrode and the titanium film there is a silicon film and a titanium silicide film. The titanium silicide film forms on the source/drain the Schottky diode that can, if appropriate, be replaced by a diode with a pn-type junction structure.
Furthermore, U.S. Pat. No. 5,710,448 discloses how a diode contact is to be implemented in such a way that an off-state current flows owing to tunnel processes.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide an integrated circuit configuration and a method for manufacturing it which overcome the above-mentioned disadvantages of the prior art devices and methods of this general type, which has a high packing density.
With the foregoing and other objects in view there is provided, in accordance with the invention, an integrated circuit configuration. The integrated circuit configuration contains a substrate having a main surface and a planar transistor having a first source/drain region and a second source/drain region disposed in the substrate and adjoining the main surface of the substrate. The planar transistor further has a gate electrode disposed above the substrate. A diode is connected between the first source/drain region and the gate electrode such that the diode makes it more difficult for a charge to flow away from the gate electrode to the first source/drain region. The diode has a diode layer containing an insulating material and is disposed on at least part of the first source/drain region. The diode layer has a thickness dimensioned such that a current through the diode layer is produced due to the tunneling of electrodes through the diode layer. The diode further has a conductive structure disposed over at least part of the gate electrode and on the diode layer.
An integrated circuit configuration contains a planar first transistor whose first source/drain region and whose second source/drain region are disposed in a substrate and adjoin a main surface of the substrate. A gate electrode of the first transistor is provided over the substrate. A diode is connected between the first source/drain region and the gate electrode in such a way that it is made more difficult for a charge to flow away from the gate electrode to the first source/drain region. A diode layer, which is part of the diode, is disposed on at least part of the first source/drain region.
A conductive structure, which is a further part of the diode, is disposed over at least part of the gate electrode and on the diode layer.
In a method for manufacturing an integrated circuit configuration, the first source/drain region and the second source/drain region of the planar first transistor are generated by masked implantation of the substrate, in such a way that they adjoin the main surface of the substrate. The gate electrode of the first transistor is formed above the substrate. A diode layer, which is part of the diode, is formed on at least part of the first source/drain region. The conductive structure, which is a further part of the diode, is formed in such a way that it is disposed over at least part of the gate electrode and on the diode layer. The diode is formed in such a way that it is made more difficult for a charge to flow away from the gate electrode to the first source/drain region.
Because the diode is disposed over the first transistor, the integrated circuit configuration can have a high packing density. In contrast to Published, European Patent Application EP 0 537 203, the first transistor can be manufactured in the same way as a transistor using currently customary semiconductor fabrication methods. The diode is manufactured only by the following process steps. The Schottky junction according to European Patent Application EP 0 537 203 must be partially generated before the completion of the transistor because the metal film is disposed under the gate electrode. In addition, the source/drain regions of the transistor according to EP 0 537 203 are not generated by implantation after the gate electrode is formed, as in the conventional method, because the gate electrode is disposed over a greater part of the first source/drain region on which the metal film is located. A further difference with respect to EP 0 537 203 consists in the fact that the gate electrode of the first transistor is not part of the diode so that, owing to the free selection of the material of the conductive structure, electrical properties of the diode can be optimized independently of the gate electrode.
If the integrated circuit configuration contains, in addition to the first transistor and the diode, a second (further) transistor whose first source/drain region is connected to the first source/drain region of the first transistor, the integrated circuit configuration can contain a DRAM cell configuration. The first transistor, the diode and the second transistor are parts of a memory cell of the DRAM cell configuration. The first transistor and the second transistor are connected between a voltage terminal and a bit line. A gate electrode of the second transistor is connected to a word line. The DRAM cell configuration is a dynamic self-amplifying memory cell configuration in this case.
The storage of a logic 1 in the memory cell can be carried out, for example, as follows: a voltage is applied to the bit line and to the word line of the memory cell so that charge flows via the diode to the gate electrode of the first transistor.
In order to store a logic 0 in the memory cell, a voltage is applied to the word line, but not to the bit line, so that current cannot flow via the diode to the gate electrode of the first transistor.
In order to read out the information, a voltage is applied to the word line and to the bit line and a test is conducted to determine whether or not a current is flowing through the bit line. If the logic 1 is stored in the memory cell, the first transistor is switched on owing to the charge on the gate electrode of the first transistor, so that a current can flow from the voltage terminal to the transistors and through the bit line. The charge is held on the gate electrode of the first transistor during the reading-out process because the polarity of the diode is disposed such that the charge can flow away via the diode only with difficulty. If the logic 0 is stored in the memory cell, no current flows through the bit line because the first transistor is switched off owing to a lack of charge at its gate electrode.
If the integrated circuit configuration contains a DRAM cell configuration, it is advantageous for the sake of reducing the process expenditure for the second transistor also to be planar. The source/drain regions and the gate electrodes of the transistors can then be generated simultaneously. In order to increase the packing density, it is particularly advantageous for the first source/drain region of the first transistor and the first source/drain region of the second transistor to be embodied as a common source/drain region. The gate electrode of the second transistor may be part of the word line.
The diode layer may contain, for example, a conductive material so that the diode is a Schottky diode.
So that the flow of the current through the diode is independent of the temperature, it is advantageous for the diode to be embodied as a tunnel diode. For this purpose, the diode layer contains an insulating material. The thickness of the diode layer is dimensioned here in such a way that a current through the diode layer is produced, essentially owing to tunneling of electrodes through the diode layer. The diode layer is composed, for example, of SiO 2 and is preferably thinner than 3 nm. The SiO 2 can be deposited or grown by thermal oxidation. The diode layer may contain nitride or silicon nitride. The diode layer may also contain a plurality of component layers. The diode is formed by the first source/drain region of the first transistor, the diode layer and the conductive structure. In contrast to the diode structure of the DRAM cell configuration according to German Patent DE 197 27 436 C1, the diode contains only three elements and can be manufactured with a smaller process expenditure.
One possible way of disposing the polarity of the diode such that it is made more difficult for current to flow from the gate electrode of the first transistor to the first source/drain region of the second transistor consists in providing a smaller doping concentration for the conductive structure than for the first source/drain region of the first transistor. The conductive structure and the first source/drain region of the first transistor are of the same conductivity type.
So that the diode layer is particularly uniform and thin, it can be grown by a rapid thermal nitridation (RTN) process at approximately 1000° C. using NH 3 . The process limits itself automatically at small thicknesses, i.e. the diode layer which has already been grown on prevents further diffusion of atoms to the main surface of the substrate.
When the diode layer is formed, a further layer can be formed on the gate electrode. The diode layer can be generated, for example, by thermal oxidation so that the further layer is formed on the gate electrode. The further layer is subsequently removed by a masked etching process.
In order to prevent the further layer from being generated on the gate electrode when the diode layer is being generated, a protective structure can be generated on the gate electrode before the diode layer is generated. The protective structure is removed after the diode layer is generated. The gate electrode preferably has a rougher surface than the first source/drain region. For example, the gate electrode can be generated from doped polysilicon and the substrate can contain monocrystalline silicon at least in the vicinity of the first source/drain region. If the diode layer is generated, for example, by thermal oxidation, the further layer is generated on the gate electrode and it grows inhomogeneously owing to the rough surface of the gate electrode. The resistance of the further layer is negligible in comparison to the resistance of the diode layer because, owing to its inhomogeneity, the further layer permits a significantly higher flow of current than the diode layer. The conductive structure is generated on the diode layer and on the further layer. Electrical resistances for the diode are significantly greater than electrical resistances that are formed by the gate electrode, the further layer and the conductive structure. Removing the further layer or generating the protective structure which protects the gate electrode against thermal oxidation, and which is subsequently removed again, is not necessary, with the result that the process expenditure is reduced.
The substrate may contain a different semiconductor material, for example germanium.
The diode layer and the further layer may be formed as parts of insulating material which is applied essentially over the entire surface, for example by unmasked thermal oxidation. In order to generate the conductive structure, the conductive material may be deposited and structured, the insulating material serving as an etch stop. Alternatively, the conductive material is patterned together with the insulating material. In both cases, just one mask, namely the mask for patterning the conductive structure, is required to generate the diode.
It lies within the scope of the invention if, after the first transistor is formed, a lower insulating layer is deposited over the transistor. A depression can be generated in the lower layer so that at least part of the gate electrode and the first source/drain region is exposed. Subsequently, the diode layer and the further layer can be generated by carrying out, for example, the thermal oxidation process. A conductive material can subsequently be deposited. Parts of the conductive material located outside the depression in the lateral direction are removed so that the conductive structure is generated from the conductive material. In order to generate the diode, just one mask is necessary here, namely the mask for generating the depression.
In the text below “height” designates a distance from the main surface of the substrate along an axis running perpendicular to the main surface.
The depression can be filled when the conductive material is deposited. The conductive material outside the depression can be removed by chemical-mechanical polishing. It lies within the scope of the invention if the height of the conductive structure is subsequently reduced by etching back the conductive material. The conductive material can also be deposited in such a way that surfaces of the depression are covered but the depression is not filled. The conductive material outside the depression can be removed by chemical-mechanical polishing.
In order to reduce the resistance of the further layer, it is advantageous if a surface of the further layer is more than approximately twice as large as a surface of the diode layer.
It lies within the scope of the invention if a capacitor whose first capacitor electrode is electrically connected to the conductive structure is disposed over the substrate. A first part of the first capacitor electrode is disposed on an edge of a projection of the first capacitor electrode onto the main surface of the substrate. The first part of the first capacitor electrode extends to a height that is greater than a height up to which a second part of the first capacitor electrode extends, the second part being disposed on along other parts of the projection. The first capacitor electrode consequently has inner edges and outer edges facing away from the projection. The first capacitor electrode is approximately pot-shaped, for example. A capacitor dielectric of the capacitor covers at least the second part of the first capacitor electrode and the inner edges of the first capacitor electrode. A second capacitor electrode of the capacitor adjoins the capacitor dielectric.
The provision of the inner edges of the first capacitor electrode brings about an increase in the capacitance of the capacitor without increasing the space required by the capacitor.
If the integrated circuit configuration contains a DRAM cell configuration, it is particularly advantageous to provide the capacitor as part of the memory cell because the amount of charge stored on the gate electrode of the first transistor can be increased, enabling the information of the memory cell to be stored over a longer time period before the information has to be refreshed.
The height of the first part of the first capacitor electrode may be less than approximately 1000 nm. Because, in contrast to the charge on a storage capacitor of a DRAM cell configuration in which a memory cell contains a transistor and the storage capacitor, the charge on the capacitor does not have to generate the signal on the bit line, but merely has to keep the first transistor in the opened state, the capacitance of the capacitor can be significantly smaller, for example five times smaller, than the capacitance of the storage capacitor. The small height of the first capacitor electrode permits the integrated circuit configuration to contain, in addition to the DRAM cell configuration, a logic circuit that is also disposed in the substrate. An insulating layer that completely covers the capacitor can be deposited and planarized. The first transistor and the second transistor can be generated simultaneously with transistors of the logic circuit.
In order to generate such a capacitor, it lies within the scope of the invention to deposit and planarize a lower insulating layer over the substrate. A depression is generated in the lower layer. The conductive material is deposited conformly to such a thickness that the depression is not filled. The first capacitor electrode is formed from the conductive material by removing the part of the conductive material located outside of the depression in the lateral direction. The first part of the first capacitor electrode is disposed on edges of the depression.
In order to further increase the capacitance of the capacitor without requiring any additional space, it is advantageous for the capacitor dielectric additionally to cover at least parts of the outer edges of the first capacitor electrode. For this purpose, part of the lower layer is removed, for example after the first capacitor electrode is generated, so that parts of the outer edges are exposed.
In order to increase process reliability, it is advantageous for an upper layer to be generated over the lower layer, in which upper layer a further depression, which is disposed over the depression, is generated. The conductive material of the first capacitor electrode is deposited after the further depression is generated. The first capacitor electrode is generated by removing the conductive material outside the depression and the further depression. After the first capacitor electrode is generated, the upper layer is removed. The lower layer may act here as an etch stop so that the process reliability is increased because a short circuit between the substrate and the second capacitor electrode is avoided by removing the lower layer. If the upper layer is not selectively etchable with respect to the lower layer, it lies within the scope of the invention if a middle layer, which serves as an etch stop, is generated between the lower layer and the upper layer.
The further depression can be generated together with the depression. Alternatively, the further depression is generated after the depression is generated.
The depression in which the first capacitor electrode is disposed can coincide with the depression in which the conductive structure of the diode is disposed.
In order to simplify the process, it is advantageous for the first capacitor electrode to coincide with the conductive structure. Moreover, the packing density of the integrated circuit configuration is increased because the capacitor is disposed over the diode and does not require any additional space.
Alternatively, the conductive structure is generated first, and then the first capacitor electrode. This provides the advantage that the conductive structure and the first capacitor electrode may be composed of different materials or have different doping concentrations. The electrical properties of the capacitor and of the diode can consequently be optimized independently of one another.
The conductive structure is composed, for example, of doped polysilicon that has a dopant concentration of between approximately 10 17 cm −3 and 10 19 cm −3 . The dopant concentration determines the current/voltage characteristic of the diode and is adapted to the respective purpose of use of the memory cell. The first capacitor electrode is composed, for example, of doped polysilicon that has the highest possible dopant concentration, for example 10 20 cm −3 .
It lies within the scope of the invention if the lower layer and the depression in which the conductive structure is formed are generated first. The upper layer, the further depression and the capacitor can be generated subsequently.
The capacitor electrode can contain SiO 2 , silicon nitride, a ferroelectric material, such as barium strontium titanate (BST) or other materials with a high dielectric constant.
The second capacitor electrode can contain, for example, doped polysilicon, silicided polysilicon and/or a metal.
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 an integrated circuit configuration and a method for manufacturing it, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic, cross-sectional view through a first substrate after a first transistor, a second transistor, transistors of a logic circuit, a lower layer and a middle layer have been formed according to the invention;
FIG. 2 a is a cross-sectional view after a depression, a diode layer, a further layer and a conductive structure have been formed;
FIG. 2 b is a plan view of the first substrate in which the transistors and the conductive structure are represented;
FIG. 3 is a cross-sectional view after an upper layer, a further depression and a first capacitor electrode have been formed;
FIG. 4 is a cross-sectional view after a capacitor dielectric and a second capacitor electrode have been formed; and
FIG. 5 is a cross-sectional view through a second substrate after the two transistors, the diode and the capacitor have been formed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In all the figures of the drawing, sub-features and integral parts that correspond to one another bear the same reference symbol in each case. The figures shown are not true to scale. Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown in a first exemplary embodiment, a planar first transistor and a planar second transistor formed from a conventional process on a main surface H of a p-type doped first substrate A made of silicon. A first source/drain region SD of the first transistor and a first source/drain region SD of the second transistor are produced as a common source/drain region (see FIG. 1 ). The first source/drain region SD of the first transistor, a second source/drain region SD 1 of the first transistor and a second source/drain region SD 2 of the second transistor have a dopant concentration of approximately 10 21 cm −3 and are n-type doped. The second source/drain region SD 1 of the first transistor is strip-shaped and is connected to a voltage terminal. A gate electrode G 1 of the first transistor and a gate electrode G 2 of the second transistor are disposed over the first substrate A and are separated from the first substrate A by a gate dielectric Gd (see FIG. 1 ). The gate electrodes G 1 , G 2 have a dopant concentration of approximately 10 20 cm −3 . The gate electrode G 2 of the second transistor is part of a strip-shaped word line. Transistors of a logic circuit Q, which is represented schematically in FIG. 1, are generated simultaneously with the two transistors.
SiO 2 is deposited to a thickness of approximately 50 nm and etched back in order to generate spacers Sp on edges of the gate electrodes G 1 , G 2 of the transistors.
The spacers Sp are provided with a layer N of silicon nitride by depositing silicon nitride to a thickness of approximately 20 nm and etching it back until the gate electrodes G 1 , G 2 of the transistors are exposed (see FIG. 1 ).
In order to generate an insulating lower layer U, SiO 2 is deposited to a thickness of approximately 800 nm by a TEOS method, and is planarized by chemical-mechanical polishing. A middle layer M is generated on the lower layer U by depositing silicon nitride to a thickness of approximately 50 nm (see FIG. 1 ).
Using a non-illustrated first photoresist mask, the silicon nitride layer M and the SiO 2 layer U are etched until a part of the first source/drain region SD of the first transistor, a part of the layer N made of silicon nitride and a part of the gate electrode G 1 of the first transistor are exposed so that a depression V is generated whose floor adjoins the first source/drain region SD of the first transistor and the gate electrode G 1 of the first transistor (see FIG. 2 a ). A surface of the exposed part of the gate electrode G 1 of the first transistor is approximately twice as large as the exposed part of the first source/drain region SD of the first transistor (see FIG. 2 b ).
After reduction cleaning with, for example, hydrofluoric acid, thermal oxidation is carried out. A diode layer S made of SiO 2 , which is approximately 1.5 nm thick, is produced on the first source/drain region SD of the first transistor. In addition, a further layer I is generated on the gate electrode G 1 of the first transistor (see FIG. 2 a ).
In order to generate a conductive structure L, polysilicon doped in situ is deposited to a thickness of approximately 70 nm so that surfaces of the depression V are covered but the depression V is not filled. By chemical-mechanical polishing, the conductive material is removed outside the depression V so that a conductive structure L is formed in the depression V made of the conductive material. The conductive structure L is disposed on the diode layer S of the diode and on the further layer I (see FIGS. 2 a and 2 b ).
The dopant concentration of the conductive structure L is approximately 10 20 cm −3 . The first source/drain region SD of the first transistor, the diode layer S and the conductive structure L form a diode which is connected between the first source/drain region SD of the first transistor and the gate electrode G 1 of the first transistor.
An electrical resistance of the diode is particularly small for a flow of current from the first source/drain region SD of the first transistor to the gate electrode G 1 of the first transistor because the current flows through the diode layer S from regions of high doping to regions of low doping. This direction of the flow of current is also referred to as the forward direction of the diode. An electrical resistance of the diode for a flow of current from the gate electrode G 1 of the first transistor to the first source/drain region SD of the first transistor is particularly large in comparison with this. The direction of the flow of current is also referred to as the off-state direction of the diode. The diode is consequently connected in such a way that it is difficult for a charge to flow from the gate electrode G 1 of the first transistor to the first source/drain region SD of the first transistor.
The effect of the further layer I on the flow of current through the diode is negligible in comparison to the effect of the diode layer S. The reason for this is that the gate electrode G 1 of the first transistor is composed of polysilicon and consequently has a rougher surface than the first source/drain region SD of the first transistor which is composed of monocrystalline silicon. The further layer I grows inhomogeneously on the rougher surface so that the further layer I is made such that high leakage currents can flow through it. A further reason for this is that a surface of the further layer I is approximately twice as large as a surface of the diode layer S.
An upper layer O is generated by depositing SiO 2 to a thickness of approximately 800 nm. A further depression V*, which is disposed above the depression V, is formed in the upper layer O using a non-illustrated second photoresist mask. The conductive structure L is exposed in the process (see FIG. 3 ).
The generation of the further depression V* is largely tolerant of a maladjustment with respect to the depression V because the etching is selective with respect to the silicon nitride so that parts of the gate electrodes G 1 , G 2 of the transistors and parts of the first substrate A cannot be exposed. The middle layer M acts as an etch stop. C 2 F 6 , for example, is suitable as the etching agent.
In order to generate a first capacitor electrode P 1 of a capacitor, in situ doped polysilicon is deposited to a thickness of approximately 50 nm and planarized by chemical-mechanical polishing so that the polysilicon is removed outside the depression V and the further depression V*. The first capacitor electrode P 1 is disposed on the conductive structure L.
The upper layer O is subsequently removed selectively with respect to etching of the polysilicon and the silicon nitride by SiO 2 so that parts of outer edges of the first capacitor electrode P 1 facing away from the centers of the depressions V, V* are exposed (see FIG. 4 ).
A capacitor dielectric Kd is generated on exposed surfaces of the first capacitor electrode P 1 by depositing silicon nitride to a thickness of approximately 7 nm and partially oxidizing it (see FIG. 4 ).
In order to generate a second capacitor electrode P 2 , in situ doped polysilicon is deposited to a thickness of approximately 100 nm (see FIG. 4 ). The second capacitor electrode P 2 has a dopant concentration of approximately 10 20 cm −3 .
By the method described above, a dynamic random access memory (DRAM) cell configuration is generated in which a memory cell contains the first transistor, the second transistor, the diode and the capacitor. An intermediate oxide Z that covers the capacitors is deposited and planarized. In the intermediate oxide Z, contact holes are etched which expose the second source/drain regions SD 2 of the second transistors of the memory cells. In order to form further spacers Sp* on edges of the contact holes, SiO 2 is deposited to a thickness of 25 nm and etched back. The contact holes are filled with tungsten so that contacts K are formed which are separated from the second capacitor electrode P by the further spacers Sp*. Bit lines B 1 that bound the contacts K and run transversely with respect to the word line are generated on the intermediate oxide.
In a second exemplary embodiment, in a way corresponding to the first exemplary embodiment, a first source/drain region SD′ of a first transistor, which acts at the same time as a first source/drain region of a second transistor, a second source/drain region SD 1 ′ of the first transistor, a second source/drain region SD 2 ′ of the second transistor, a gate electrode G 1 ′ of the first transistor, a gate electrode G 2 ′ of the second transistor, a gate dielectric GD′, spacers Sp′, a layer N′ made of silicon nitride, a diode layer S′, a further insulating layer I′, an insulating lower layer U′, a middle layer M′, a depression V′ and a conductive structure L′ are generated on the basis of a second substrate B made of silicon (see FIG. 5 ). In contrast to the first exemplary embodiment, the thickness of the lower insulating layer U′ is, however, approximately 1200 nm. The conductive structure L′ serves at the same time as a first capacitor electrode of a capacitor.
In a way corresponding to the first exemplary embodiment, a capacitor dielectric Kd′ is generated. Because the outer edges of the first capacitor electrode, i.e. of the conductive structure L′, are not exposed, the capacitor dielectric Kd′ is generated only on inner edges, facing a center of the depression V′, of the conductive structure L′ (see FIG. 5 ).
As in the first exemplary embodiment, a second capacitor electrode P 2 ′ is generated by depositing in situ doped polysilicon.
As in the first exemplary embodiment, a DRAM cell configuration, in which a memory cell contains the first transistor, the second transistor, the diode and the capacitor, is also generated here.
A large number of variations of the exemplary embodiments that also lie within the scope of the invention are conceivable. Thus, dimensions of the layers, structures, depressions and regions can be adapted to the respective requirements. The same applies to the dopant concentration and to the selection of materials.
The source/drain regions can be p-type doped, and the substrates can be n-type doped.
It is possible to dispense with the generation of capacitors.
A further possible way of connecting the first source/drain regions to the voltage terminal contains forming, after the second capacitor electrode has been generated, a first intermediate oxide into which contact holes to the second source/drain regions of the first transistors are generated. The contact holes are provided with insulating spacers and filled with tungsten so that contacts are generated. Metal tracks that connect the contacts to the voltage terminal are formed by depositing and patterning conductive material. A further intermediate oxide is subsequently generated and the contact holes for the bit lines are generated in it. Contacts and the bit lines are formed as described above. | An integrated circuit contains a planar first transistor and a diode. The diode is connected between a first source/drain region of the first transistor and a gate electrode of the first transistor such that a charge is impeded from discharging from the gate electrode to the first source/drain region. A diode layer that is part of the diode is disposed on a portion of the first source/drain region. A conductive structure that is an additional part of the diode is disposed above a portion of the gate electrode and is disposed on the diode layer. The diode can be configured as a tunnel diode. The diode layer can be produced by thermal oxidation. Only one mask is required for producing the diode. A capacitor can be disposed above the diode. The first capacitor electrode of the capacitor is connected to the conductive structure. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. application Ser. No. 12/802,839, filed on Jun. 14, 2010, which claims the benefit of U.S. Provisional Application Ser. No. 61/268,423, filed on Jun. 12, 2009. These prior applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to gas generating systems and, more particularly, to end closure assemblies and elements thereof usable for closing and/or sealing a housing of a gas generating system, such as an inflator or gas generator.
When manufacturing an inflator or gas generator, an igniter or initiator is typically sealed to the gas generator by machining a body bore seal, and structurally welding the body bore seal to the base of the associated inflator. The igniter is then subsequently sealed within the inflator by forming a sealing interface with the body bore seal. The process is not only relatively expensive, but is time-consuming as well.
When manufacturing an inflator or gas generator, yet another consideration is the strength and robustness of the housing or pressure vessel. Oftentimes, special considerations must be taken to fortify the structural design of the pressure vessel, increasing the manufacturing complexity and cost of the inflator.
SUMMARY OF THE INVENTION
In one aspect of the embodiments of the present invention, an end closure sub-assembly for an inflator is provided. The sub-assembly includes an end closure and a retainer directly attached to the end closure. The end closure includes an end closure base portion and a first wall extending from the base portion to define an end closure initiator receiving portion. The retainer includes a flat retainer base portion and a wall extending from the retainer base portion to define a retainer initiator receiving portion. The end closure initiator receiving portion and the retainer initiator receiving portion define a cavity therebetween, wherein the cavity does not include an initiator positioned therein.
In another aspect of the embodiments of the present invention, an end closure sub-assembly for an inflator is provided. The sub-assembly includes an end closure and a retainer attached to the end closure. The end closure includes an end closure base portion and a wall extending from the base portion to define an end closure initiator receiving portion. The retainer includes a flat retainer base portion and a first retainer wall extending from the retainer base portion to define a retainer initiator receiving portion. The end closure initiator receiving portion and the retainer initiator receiving portion combine to define a cavity therebetween, the cavity being structured to enable insertion of an initiator therein after attachment of the retainer to the end closure.
In another aspect of the embodiments of the present invention, a method of manufacturing an inflator is provided, comprising steps of: providing a retainer having a wall defining a retainer initiator receiving portion; providing an end closure having a wall defining an end closure initiator receiving portion structured for insertion into the retainer initiator receiving portion; inserting the end closure initiator receiving portion into the retainer initiator receiving portion to form a cavity defined by a portion of the retainer wall and a portion of the end closure wall; securing, after inserting the end closure initiator receiving portion into the retainer initiator receiving portion, the retainer to the end closure; inserting, after securing the retainer to the end closure, an initiator into the cavity; and securing the initiator in the cavity.
In another aspect of the embodiments of the present invention, a cap sub-assembly for an inflator is provided. The sub-assembly includes a cap having a base portion with a flat portion and a wall extending from a perimeter of the base portion, and a filter retainer including a base portion having a flat portion and a wall extending from a perimeter of the base portion. The cap base portion has a flat portion. The flat retainer base portion is welded to the flat portion of the cap base portion such that the flat retainer base portion inhibits deflection of the flat cap base portion.
In another aspect of the embodiments of the present invention, an inflator is provided. The inflator includes an end closure and a cap coupled to the end closure so as to form a gas-tight seal therebetween. A initiator retainer is directly attached to the end closure such that the initiator retainer inhibits deflection of the portion of the end closure attached thereto. A filter retainer is directly attached to the cap such that the filter retainer inhibits deflection of the portion of the cap attached thereto.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings illustrating embodiments of the present invention:
FIG. 1 is an exploded view of an end closure sub-assembly in accordance with an embodiment of the present invention.
FIG. 2 is an assembled view of the end closure sub-assembly shown in FIG. 1 .
FIG. 3 is an exploded view of another end closure sub-assembly in accordance with an embodiment of the present invention, incorporating the sub-assembly shown in FIG. 2 .
FIG. 4 is an exploded view of an end closure assembly in accordance with an embodiment of the present invention, incorporating the sub-assembly shown in FIG. 3 .
FIG. 5 is a cross-sectional side view of an exemplary gas generating system incorporating the end closure assembly shown in FIG. 4 .
FIG. 6 is a schematic view of an airbag system and a vehicle occupant protection system incorporating a gas generating system including an end closure assembly in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
When portions of the end closure, cap, filter retainer and initiator retainer 14 are described herein as being “flat”, it is understood that the flat portions of these surfaces are predominantly flat with the exception of features such as localized bumps, indentations, or other features formed in the surfaces to facilitate resistance or projection welding or other attachment methods suitable for the functions and applications described herein.
For the purposes described herein, elements of the inflator embodiments described herein are directly attached to each other when there is a direct connection (such as a weld, brazed connection, etc.) between the elements which joins the elements so that they move as a single part.
FIG. 1 is an exploded view of an end closure sub-assembly 10 in accordance with an embodiment of the present invention. FIG. 2 is an assembled view of the end closure sub-assembly shown in FIG. 1 . Sub-assembly 10 includes an end closure 12 configured for attachment to a housing 52 (see FIG. 5 ) of a gas generating system for closing and/or sealing the housing, and an initiator retainer 14 attached to end closure 12 .
In the embodiment shown in FIGS. 1 & 2 , end closure 12 has a first base portion 12 a and a first wall 12 b extending along a periphery of the first base portion 12 a . In the particular embodiment shown in FIGS. 1 & 2 , a flange 12 c extends outwardly from wall 12 b . In other embodiments, flange 12 c is not included. End closure base portion 12 a includes an opening 12 d for receiving a portion of an associated initiator 18 therein. Base portion 12 a may alternatively include multiple openings 12 d for receiving multiple associated initiators therein; it will be appreciated that the openings 14 d in the second base portion 14 a (described below) will correspond to the number of openings 12 d.
In the particular embodiment shown in FIGS. 1 & 2 , opening 12 d is provided in an initiator-receiving portion 12 e of base portion 12 a . Initiator-receiving portion 12 e is connected to base portion 12 a by a wall 12 f and extends from base portion 12 a in a direction toward an interior of the gas generating system when the end closure is attached to the system housing. This enables the terminals or contacts 28 of the initiator 18 to be recessed within the end closure as shown in FIG. 5 for protection.
In the embodiment shown, initiator-receiving portion 12 e and a first annular wall 12 f extend from a central portion of the end closure 12 . However, any initiator-receiving portion and its associated wall may be spaced apart from the center of the end closure, depending on the design considerations and geometry of a particular gas generating system.
Initiator-receiving portion 12 e may be fabricated using any suitable technique, depending on such factors as the materials from which the end closure is formed, the shape of the initiator-receiving portion, and other requirements of a particular application. In one embodiment, end closure 12 is formed from a metallic material and initiator-receiving portion 12 e and wall 12 f are drawn in the material. In another embodiment, end closure 12 is formed from a polymer material and initiator-receiving portion 12 e and wall 12 f are molded into the base portion 12 a.
End closure 12 may be formed form any suitable material (for example, a metal, metal alloy, or polymer) suitable for the requirements of a particular application.
Referring again to FIGS. 1 & 2 , initiator retainer 14 has a base portion 14 a including a formed portion or second annular wall 14 b extending in a direction toward an interior of the gas generating system when the end closure is attached to the system housing. Formed portion 14 b defines an opening 14 d configured for receiving a portion of initiator 18 therein. As shown in FIGS. 1 & 2 , when retainer 14 is joined to end closure 12 , the second annular wall 14 b is joined in nested relationship over first annular wall 12 f , respectively. Stated another way, as shown in the embodiment of FIGS. 1 & 2 , the shape of metallic initiator retainer 14 substantially conforms to the shape of metallic end closure 12 , thereby facilitating nested relationship of retainer 14 over end closure 12 . When joined in this manner, the juxtaposed annular walls 14 b and 12 f form an annular wall 15 for containment, seating, and sealing of an initiator 18 , as described below. However, in alternative embodiments, the initiator retainer 14 may have any shape suitable for the requirements of a particular application.
Embodiments of the initiator retainer 14 include features which facilitate attachment of the initiator retainer 14 to the end closure 12 such that the initiator retainer inhibits deflection of the end closure responsive to an increase in internal pressure within the inflator housing. In the examples shown in FIGS. 1 & 2 , retainer 14 is secured to end closure 12 by projection welding together (or otherwise suitably attaching) abutting sections of their respective base portions 14 a and 12 a . More specifically, in the examples shown in FIGS. 1 & 2 , at least a portion the end closure base portion 12 a is flat, at least a portion of the initiator retainer base portion 14 a is flat, and the flat portions of the initiator retainer and end closure base portions are welded together, such that the flat retainer base portion inhibits deflection of the flat end closure base portion.
In one embodiment, the overall wall thickness of the housing may be substantially reduced by 35 to 40% of its original thickness, by virtue of the reinforced area of the welded base portions 12 a and 14 a . For example, it has been found in one embodiment that the wall thickness may be reduced from a typical thickness of about 2.2 millimeters to about 1.4 millimeters. As a result, the pressure vessel strength is substantially enhanced, by essentially doubling the base material thickness, while minimizing the overall housing thickness required. Other base and housing thicknesses may be iteratively determined, depending on the type of inflator, and depending on the ignition and gas generation chemistry employed. Other modes of attachment are also contemplated depending on the geometries of the end closure 12 and the initiator retainer 14 , and other design, materials, and operational factors.
In one embodiment, shown in FIGS. 1 & 2 , initiator retainer 14 is made from a metallic material and formed portion or second annular wall 14 b is fabricated by drawing a portion of the initiator retainer material in the direction shown. However, it will be realized that alternative configurations suitable for receiving the initiator 18 therein may be utilized, and that other suitable fabrication methods may be used to produce such alternative configurations. In addition, retainer 14 can be made from any other suitable material (for example, a polymer).
In the embodiment shown, formed portion or second annular wall 14 b is provided in a central portion of the initiator retainer 14 . However, any formed portion(s) 14 b of the initiator retainer may alternatively be spaced apart from the center of the initiator retainer, depending on the design considerations and geometry of a particular gas generating system.
Formed portion or second annular wall 14 b may be stepped as shown in FIGS. 1 & 2 to meet processing requirements of the initiator retainer material (for example, in the case of a metallic retainer), to facilitate recessed mounting of the initiator as shown in FIG. 5 , or to meet other design requirements of a particular gas generating system.
In the embodiment shown in FIGS. 1&2 , a wall 14 c extends along a periphery of the base portion 14 a , for engaging or helping to contain another element of the gas generating system. However, in alternative embodiments, wall 14 c may be omitted if desired.
Initiator retainer 14 may be formed from any suitable material, for example a metallic material or a polymer material. Initiator 18 may be any suitable initiator known in the art. One exemplary initiator construction is described in U.S. Pat. No. 6,009,809, incorporated herein by reference. In the embodiment shown in FIGS. 1 - 4 , a third annular wall 14 g contiguous with formed portion or second annular wall 14 b is structured to enable crimping of the wall 14 g over a portion of initiator 18 , to retain the initiator in the retainer 14 . Other methods (for example, press-fitting or adhesive application) of securing the initiator to the retainer are also contemplated.
If desired, a resilient seal 90 (such as an o-ring seal) or other type of seal may be positioned between the initiator 18 and the retainer 14 to prevent the escape of generated gases through the initiator-retainer interface.
Referring to FIG. 4 , if desired, a connector retainer 30 may be incorporated into the end closure assembly for retaining a connector (not shown) coupled to the initiator terminals 28 when the gas generating system is installed in a vehicle or other device. The connector operatively couples the initiator 18 to a device or mechanism for actuating the initiator when the need for generated gases arises.
Referring now to FIG. 5 , an end closure assembly 11 as shown in FIG. 4 is shown incorporated into a gas generating system 50 . System 50 has a housing 52 , wherein the housing 52 is formed from a first housing portion or cap 54 and an end closure assembly or base 11 secured to the first housing portion 54 , so as to form a substantially hermetic seal between the first housing portion 54 and the end closure assembly 11 . Housing 52 has one or more gas exit apertures 57 formed therein to enable fluid communication between an interior of the housing and an exterior of the housing upon activation of the gas generating system.
A tube 26 may be positioned within the gas generating system to enclose a portion of initiator 18 and for receiving a booster material 60 in an interior thereof. Tube 26 is generally cylindrical and may be secured within housing 52 by welding or any other suitable method. Tube 26 has at least one opening 91 formed therein to enable fluid communication between the interior of the tube and an exterior of the tube upon activation of the gas generating system. Tube 26 may be extruded, roll formed, or otherwise metal formed and may be made from carbon steel, stainless steel, or any other suitable material. In a particular embodiment, tube 26 is formed from a thermally-conductive material to facilitate heat transfer between a heat-activated auto-ignition material (not shown) and a portion of the gas generating system housing in thermal contact with tube 26 and exposed to elevated temperatures occurring on the exterior of the housing, due to a fire for example. Ignition of the auto-ignition material produces ignition of booster material 60 or gas generant material in thermal communication with the auto-ignition material, in a manner known in the art.
A plurality of annular gas generant wafers 62 are stacked around and adjacent tube 26 . In the embodiment shown in the drawings, wafers 62 are annular in shape and each wafer 62 has substantially the same dimensions. However, the wafers may have any of a variety of alternative shapes positionable within housing 52 . In addition, other, alternative forms of gas generant (for example, tablets) may be used. Examples of gas generant compositions suitable for use in the embodiments of the present invention are disclosed in U.S. Pat. Nos. 5,035,757, 6,210,505, and 5,872,329, incorporated herein by reference. However, the range of suitable gas generants is not limited to that described in the cited patents.
Referring again to FIG. 5 , appropriately shaped pads or cushions 64 may be provided at one or more ends of the stack of gas generant wafers 62 for holding the gas generant wafers in place and/or for cushioning the gas generant wafers against vibration and impact. Cushions 64 may be formed from a ceramic fiber material, for example.
Booster material 60 may be positioned in tube 26 to facilitate combustion of gas generant 62 . Activation of initiator 18 produces combustion of the booster material, thereby effecting ignition of gas generant material 62 in a manner known in the art.
A quantity of a known heat-activated auto-ignition material (not shown) may be positioned within the gas generating system so as to enable fluid communication between the auto-ignition material and any associated gas generant material and/or any associated booster material upon activation of the gas generating system. The auto-ignition material is a pyrotechnic material which is ignited by exposure to a temperature lower than the ignition temperature of the associated gas generant. As is known in the art, the auto-ignition material is ignited by heat transmitted from an exterior of the system housing to the interior of the housing due to an elevated external temperature condition (produced, for example, by a fire). Combustion of the auto-ignition material results in combustion of the associated gas generant, either directly or through intervening combustion of the booster material. Suitable auto ignition materials are known to those skilled in the art. Examples of suitable auto-ignition materials are nitro-cellulose based compositions and gun powder.
FIG. 5 shows a cap sub-assembly in accordance with an embodiment of the present invention, including a cap 54 and a filter retainer 80 positioned in and attached to the cap. Referring to FIG. 5 , a filter retainer 80 has a base portion 80 a including a formed portion or second annular wall 80 b extending in a direction toward an interior of the gas generating system when the cap 54 is attached to the base assembly 11 . Embodiments of the filter retainer 80 and/or the cap 54 include features which facilitate attachment of the filter retainer to the cap 54 such that the filter retainer inhibits deflection of the cap responsive to an increase in internal pressure within the inflator housing. In the example shown in FIG. 5 , filter retainer 80 is secured to cap 54 by projection welding together (or otherwise suitably attaching) abutting sections of their respective base portions 54 a and 80 a , in a manner similar to the attachment of initiator retainer 14 to end closure 12 as previously described. More specifically, in the example shown in FIG. 5 , at least a portion the cap base portion 54 a is flat, at least a portion of the filter retainer base portion 80 a is flat, and the flat portions of the filter retainer and cap base portions are welded together, such that the flat retainer base portion inhibits deflection of the flat cap base portion.
In one embodiment, the overall wall thickness of the housing along cap base portion 54 a may be reduced by 35 to 40% of its original thickness, due to the structural reinforcement provided by welding filter retainer base portion 80 a to cap base portion 54 a . For example, it has been found in one embodiment that the wall thickness of cap base portion 54 a may be reduced from a typical thickness of about 2.2 millimeters to about 1.4 millimeters. As a result, the strength of the housing as a pressure vessel is substantially enhanced, by essentially doubling the thickness of the housing along the cap base portion 54 a , while minimizing the required thickness of the cap base portion itself. Alternative required base portion and housing thicknesses may be iteratively determined, depending on the type of inflator, and depending on the ignition and gas generation chemistry employed. Methods of attaching the filter retainer base portion 80 a to the cap base portion 54 a other than welding are also contemplated depending on the geometries of the filter retainer and cap, and other design, materials, and operational factors. Filter retainer 80 may be formed from a metallic material or from any other suitable material.
In the embodiment shown in FIG. 5 , filter retainer wall 80 b extends along a periphery of the base portion 80 a , for engaging or helping to position and/or contain another element of the gas generating system (in this case, filter 78 ). However, in alternative embodiments, wall 80 b may be omitted if desired.
A filter 78 may be incorporated into the inflator design for filtering particulates from gases generated by combustion of gas generant material 62 . In general, filter 78 is positioned between any gas generant material in the housing and any gas exit apertures 57 formed in housing 52 . In the embodiment shown in the drawings, filter 78 is positioned between initiator retainer wall 14 c and a similar wall 80 b formed along a periphery of a filter retainer 80 and aligned with wall 14 c . Filter retainer 80 is secured within housing 52 using any suitable method. The filter may be formed from one of a variety of materials (for example, a carbon fiber mesh or sheet) known in the art for filtering gas generant combustion products.
In operation, the gas generant material 62 is ignited by activation of first initiator assembly 18 and the resulting ignition of booster material 60 . Gases resulting from the combustion of the gas generant flow through filter 78 , exiting the gas generating system through gas exit openings 57 .
In yet another aspect of the invention, and as inherently shown in the Figures, a method of manufacturing an inflator, or more specifically, a method of sealing a gas generant igniter within an inflator, is described by the following steps:
1. Providing an annular end closure plate 12 having a predetermined first annular wall shape; 2. Providing an annular igniter retainer 14 having a second annular wall shape substantially congruent to and conforming to the shape of the annular end closure plate 12 ; 3. Overlaying the end closure plate 12 with the annular igniter retainer 14 to juxtapose the second annular wall shape and the first annular wall shape; 4. Welding or otherwise fixing the annular igniter retainer to the end closure plate; 5. Providing an annular seal for seating within the second annular wall shape; 6. Inserting an igniter through the juxtaposed first and second annular walls; And 7. Crimping or otherwise sealing the igniter within the annular igniter retainer.
It will be appreciated that the inflator is otherwise manufactured as known in the art and may for example, incorporate known gas generant, booster, and ignition compositions. Other structural features of the inflator may be made as known to one of ordinary skill in the art.
It will be appreciated that inflators or gas generators manufactured in accordance with the present invention enjoy at least one or more of the following benefits. The present method of sealing an igniter within a gas generator, inherent within the end closure assembly described 11 herein, provides a relatively low-cost method of sealing the inflator. Furthermore, the relatively-expensive body bore seal is eliminated as is the relatively expensive and time-consuming structural weld necessitated when employing the body bore seal. The present end closure assembly 11 may be adapted to various initiator and connector retainers, and therefore presents a broad solution to many types of inflators. Additionally, the present end closure assembly presents a relatively strong pressure vessel given the increased relative thickness of the base, a doubling of the base wall thickness for example.
Referring to FIG. 6 , in a particular application, an embodiment of a gas generating system 50 incorporating the features described above is incorporated into an airbag system 100 . Airbag system 100 comprises a housing 102 having a rupturable frontal closure 114 (not shown), an airbag 116 , and a gas generating system 50 in accordance with an embodiment of the present invention. Airbag system 100 may include (or be in communication with) a crash event sensor 210 (for example, an inertia sensor or an accelerometer) including a known crash sensor algorithm that signals actuation of initiator 18 previously described.
Referring again to FIG. 6 , any embodiment of a gas generating system 50 incorporating the features described above (or an airbag system including such a gas generating system) may be incorporated into a broader, more comprehensive vehicle occupant protection system 180 including additional elements such as, for example, a safety belt assembly 150 . FIG. 6 shows a schematic diagram of one exemplary embodiment of such a protection system.
Safety belt assembly 150 includes a safety belt housing 152 and a safety belt 225 in accordance with the present invention extending from housing 152 . A safety belt retractor mechanism 154 (for example, a spring-loaded mechanism) may be coupled to an end portion of the belt. In addition, a safety belt pretensioner 156 may be coupled to belt refractor mechanism 154 to actuate the retractor mechanism in the event of a collision. Typical seat belt retractor mechanisms which may be used in conjunction with the safety belt embodiments of the present invention are described in U.S. Pat. Nos. 5,743,480, 5,553,803, 5,667,161, 5,451,008, 4,558,832 and 4,597,546, incorporated herein by reference. Illustrative examples of typical pretensioners with which the safety belt embodiments of the present invention may be combined are described in U.S. Pat. Nos. 6,505,790 and 6,419,177, each incorporated herein by reference.
Safety belt system 150 may include (or be in communication with) a crash event sensor 158 (for example, an inertia sensor or an accelerometer) including a known crash sensor algorithm that signals actuation of belt pretensioner 156 via, for example, activation of a pyrotechnic igniter (not shown) incorporated into the pretensioner. U.S. Pat. Nos. 6,505,790 and 6,419,177, previously incorporated herein by reference, provide illustrative examples of pretensioners actuated in such a manner.
It will be understood that the foregoing descriptions of various embodiments of the present invention is for illustrative purposes only. As such, the various structural and operational features herein disclosed are susceptible to a number of modifications, none of which departs from the scope of the present invention as defined in the appended claims. | A gas generator contains a housing containing an end closure assembly. An annular end closure is fixed within an annular igniter retainer thereby forming an annular wall for retention of an associated igniter. A first base portion of the annular end closure, and a second base portion of the annular igniter retainer are fixed together, by projection-welding for example, thereby facilitating a cost-effective seal about the igniter when assembled therewith. | 1 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable.
BACKGROUND OF THE INVENTION
The present invention relates generally to liquid applicators. More specifically, the present invention relates to a hand-held liquid applicator having a flexible elongated hollow body within which a liquid-filled, glass ampule is received, and a mechanism for fracturing the ampule to release the liquid for dispensing.
Applicators for applying liquids such as medicaments or cleansing agents are known in the prior art. Conventional applicators typically provide a generally cylindrical body construction and include a glass ampule retained within the body; a sponge or tip secured to the body, at least one surface of which is exposed to the ampule; and a means for fracturing the ampule such that when the ampule is fractured, the liquid stored therein is dispensed to the sponge for application. In such applicators, the liquid-filled ampule is typically fractured by the user grasping the body wall and exerting a squeezing force directly thereon. Of course, the squeezing force necessary to fracture the ampule depends upon a number of factors such as the shape of the ampule, the material of which the body and ampule are formed, and the location at which the force is exerted.
Numerous problems are encountered with applicators of this type. For example, known applicators either include an unnecessarily large number of moving parts, which renders such devices expensive and complicated to construct as a disposable assembly, or require that a user employ both hands in breaking the ampule and dispensing the fluid.
In many situations, it is necessary for the user of a liquid dispenser of antiseptics or medicaments to use one hand to expose or position a portion of a patient's body which is to be treated with the liquid, while preparing the dispenser for use and applying the liquid with the other hand. For example, liquid applicators are often used to apply a pre-operative liquid, such as an isopropyl alcohol or iodine based solution, to an area of the body just prior to surgery. Thus, it is essential that the user be able to prepare and use the applicator with only one hand in order to enable the practical use thereof.
Another problem is that conventional applicators are often difficult to grasp and hold onto while exerting the squeezing pressure necessary to fracture the ampule or while applying the liquid to a surface. A further problem is that when the body wall is squeezed to fracture the ampule, nothing prevents the ampule from being pushed toward the open side of the hollow body after the ampule has been fractured. Accordingly, shards or pieces of the fractured ampule have a tendency to penetrate and poke into or through the sponge. In situations wherein the applicator is being used to apply a liquid to the skin of a patient, shards of glass protruding into or through the sponge obviously will be detrimental.
As such, there remains a need in the hand-held liquid applicator industry for a liquid applicator that is simple and inexpensive to construct relative to prior art applicators and which diminishes the risk of the user being injured by shards of the ampule penetrating the sponge or tip. Further, there is a need for a liquid applicator that has an improved gripping structure which provides the stability necessary to exert the squeezing pressure required and to apply the liquid to a surface.
SUMMARY OF THE INVENTION
Accordingly, in one of its aspects, the present invention provides an improved hand-held liquid applicator of quality construction having a body which may be squeezed to fracture the ampule enclosed therein, releasing the liquid contained in the ampule so that the liquid may be applied by the sponge.
In another of its aspects, the present invention provides an applicator which permits the user to squeeze the body at a location remote from the body wall which defines the internal chamber.
In still another of its aspects, the present invention provides one or more members for gripping the applicator which enhance handling of the applicator while permitting the aforementioned remote squeezing.
In yet another of its aspects, the present invention provides a disposable liquid applicator which permits single-handed operation in order to free the second hand of the user for use in assisting the application of liquid to a desired area.
In a still further aspect, the present invention provides a liquid applicator that is simple to construct and assemble and therefore may be manufactured more economically than prior art applicators.
In accordance with these and other aspects evident from the following description of a preferred embodiment of the invention, the liquid applicator for applying a desired liquid to a surface includes an elongated closed ampule, a flexible elongated hollow body which defines an internal chamber adapted to receive the ampule, and a porous element adapted to be used as an applicator for the liquid sealed to the body. The ampule is formed of a frangible material and contains a volume of liquid to be dispensed. The body presents axially opposed open and closed ends and includes a pair of diametrically opposed gripping members projecting therefrom which are suitable to be actuated by a user's fingers. The gripping members are spaced from the body at a distal end thereof The body also includes a flange protruding from the open end thereof upon which the porous element is supported. The porous element is sealed to the flange thus closing off the open end of the body. The body also may include structure for fracturing the ampule, the structure being interposed between the body and the gripping members. The hollow body further may include a plurality of inwardly projecting ridges positioned on the inner circumference thereof which act to support the ampule in the body and aid in securing the ampule in place upon fracture.
In use, the gripping members are squeezed toward one another causing the fracturing structure to exert a force against the ampule. The force causes fracturing of the ampule such that when the porous element is placed against the surface to which the liquid is to be applied, the liquid flows through the porous element and onto the surface. Fragments of the broken ampule are held in place by the inwardly projecting ridges, thus preventing shards of glass from poking or protruding through the porous element when the liquid is applied to the desired surface.
The present invention further provides a liquid applicator adapted to receive a fracturable ampule containing a volume of liquid to be applied, the applicator comprising a flexible elongated hollow body shaped for receiving the ampule, a pair of elongated gripping members diametrically projecting from the body, and a porous element adapted to be used as an applicator for the liquid. The body presents axially opposed open and closed ends as well as a flange protruding from the open end thereof to which the porous element is secured. The body also may include structure for fracturing the ampule, the structure being interposed between the body and the gripping members. The body further may include a plurality of inwardly projecting ridges positioned on the inner circumference thereof which support the ampule in the body and secure the ampule in place upon fracture.
In use, the gripping members are squeezed toward one another causing the fracturing structure to exert a force against the ampule. The force causes fracturing of the ampule such that when the porous element is placed against the surface to which the liquid is to be applied the liquid flows through the porous element and onto the surface. Fragments of the broken ampule are held in place by the inwardly projecting ridges, thus preventing shards of glass from protruding through the porous element when the liquid is applied to the desired surface.
The present invention further provides a method of applying a liquid with a liquid applicator, the method comprising the steps of providing a flexible hollow elongated body having axially opposed open and closed ends and shaped for receiving a frangible ampule containing a volume of liquid to be applied; coupling to the body a pair of elongated gripping members which project diametrically from the body and are suitable to be actuated by a user's fingers; and securing to the body a porous element which is positioned to close off the open end thereof. The method also may include the step of interposing a structure for fracturing the ampule between the body and the gripping members. Upon depression of the gripping members, the fracturing structure flexes the body inwardly to exert a fracturing force against the ampule. Thus, upon placement of the porous element against the surface to which liquid is to be applied, the liquid flows into the body and through the element.
By providing a liquid applicator in accordance with the present invention, numerous advantages are realized. For example, handling of the applicator is enhanced. Handling of the applicator is extremely important when it is employed as a cleansing agent dispenser in preparation for surgery wherein such use conditions are rigorous and slippery. Further, the risk of the user being injured by shards of a fractured ampule penetrating the porous element is diminished as the inwardly projecting ridges positioned onthe inner circumference of the body facilitate maintaining the ampule in position well below the open end of the body.
Additional aspects of the invention, together with the advantages and novel features appurtenant thereto, will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned from the practice of the invention. The objects and advantages of the invention may be realized and attained by means, instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings which form a part of the specification and are to be read in conjunction therewith, and in which like reference numerals are employed to indicate like parts in the various views:
FIG. 1 is a perspective view of a liquid applicator constructed in accordance with a preferred embodiment of the invention;
FIG. 2 is a top plan view constructed in accordance with a preferred embodiment of the invention;
FIG. 2 a is a cross-sectional view taken generally along line 2 a — 2 a of FIG. 2;
FIG. 3 is an enlarged fragmentary view of the area enclosed by line 3 in FIG. 2;
FIG. 4 is a fragmentary cross-sectional view taken generally along line 4 — 4 of FIG. 1, the liquid illustrated in dashed lines;
FIG. 5 is an enlarged fragmentary cross-sectional view of the liquid applicator as shown in FIG. 4 with the fracturing structures employed to fracture the glass ampule, the liquid illustrated in dashed lines;
FIG. 6 . is a cross-sectional view taken along line 6 — 6 of FIG. 4 illustrating the porous element and laminate material after the ampule has been fractured and liquid is allowed to flow toward the porous element; and
FIG. 7 is an exploded bottom perspective view of the liquid applicator of FIG. 1 illustrating the placing of the porous element on the flange of the body.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings in general and initially to FIG. 1 in particular, where like reference numerals identify like elements in the various views, a liquid applicator manifesting aspects of the invention is illustrated and designated generally by the numeral 10 . The liquid applicator 10 generally includes a body 12 , a closed ampule for containing liquid 14 received in the body 12 , and a porous element 16 secured to the body 12 .
The ampule 14 can be used for containing various liquids such as medicaments, cleansing agents, cosmetics, polishes or the like. In the illustrated embodiment, the ampule 14 contains an antiseptic solution to be applied to a patient's skin prior to surgery. The ampule 14 is illustrated as an elongated cylinder which defines a central longitudinal axis. However, it will be appreciated that the principles of the present invention also may be applied to spherical or elongated polygonal ampules. Preferably, the ampule 14 is formed of glass, although other materials are entirely within the scope of the present invention. The wall of the glass ampule 14 is of a thickness sufficient to contain the desired liquid during transport and storage, yet allow the ampule to be fractured upon the application of localized pressure.
As shown in FIGS. 1, 2 and 7 , the body 12 is of a generally hollow cylindrical shape and includes axially opposed first and second ends 18 , 20 . The proximal first end 18 is open and the distal second end 20 is closed. The preferred body 12 is formed of high density polyethylene, although any material exhibiting similar flexibility and integrity may be used. In the preferred embodiment, the second end 20 is closed during the molding process obviating the need for a cap or the like. The preferred body 12 is elongated and defines a central longitudinal axis which is collinear with the central longitudinal axis of the ampule 14 . Preferably, the thickness of the wall is between 0.05 and 0.15 inches. More preferably, the thickness of the wall is approximately 0.115 inches.
The body 12 includes an interior wall 21 which defines an internal chamber 22 within body 12 . Interior wall 21 is shaped to conform generally with the shape of the ampule 14 which is received within the internal chamber 22 . The circumference of the interior wall 21 is slightly larger than the outer surface of the ampule body such that a plurality of inwardly projecting ridges 40 positioned on the interior wall 21 of the hollow body 12 support the ampule 14 therein. Preferably, the interior wall 21 includes four inwardly projecting ridges 40 which are offset from one another by approximately 90° around the interior wall 21 of body 12 . The ridges 40 engage the periphery of the ampule to maintain the ampule 14 within the internal chamber 22 and prevent untoward 20 movement of shards of the ampule through the porous element 16 when fracturing of the ampule is effected, as more fully described below.
The body 12 further presents a flange 24 protruding from the open end 18 along the periphery thereof. In the preferred embodiment, the flange 24 is continuously molded to the body 12 and is disposed at an angle, a, such as 45°, with respect to the central longitudinal axis of the body. The flange 24 is adapted to support the porous element 16 , as more fully described below.
With reference to FIG. 3, the body 12 also includes a pair of elongated gripping members 26 , 28 which are diametrically opposed and project from the body. Each gripping member 26 , 28 includes an attachment portion 30 outwardly extending from the body 12 and a handling portion 32 extending from the distal end of the attachment portion 30 . Preferably, the attachment portion 30 of each gripping member 26 , 28 extends outwardly from body 12 at an angle, β, of between 36.5° and 37.5°. More preferably, attachment portion 30 extends from body 12 at approximately 36.8°.
The handling portion 32 is spaced from the body 12 and is positioned generally parallel to the central longitudinal axes of both the body and the ampule 14 . As illustrated in FIGS. 1-3, each handling portion 32 is positioned substantially in a plane defined by the central longitudinal axis, “x”, of the body 12 . Preferably, the handling portion 32 is spaced between 0.30 and 0.35 inches from the body 12 . More preferably, the handling portion 32 is spaced approximately 0.325 inches from the body 12 . The handling portion 32 of each gripping member 26 , 28 includes a textured outer surface 34 to facilitate handling of the applicator 10 and to inhibit slippage from the user's hand during application.
In the preferred embodiment, gripping members 26 , 28 are continuously molded with body 12 . It will be understood and appreciated, however, that separately formed gripping members are contemplated to be within the scope of the present invention.
As shown in FIG. 3, body 12 also includes structure for fracturing the ampule 14 . Preferably, the structure includes breaking tabs or tappets 36 , 38 interposed between the gripping members 26 , 28 and the body 12 . It will be appreciated, however, that the principles of the present invention are equally applicable to various other structure for fracturing the ampule 14 , such as multiple breaking tabs and one or more retaining tabs. The textured outer surface 34 of the gripping members 26 , 28 present a gripping area which is significantly larger than the area of the tabs 36 , 38 . Upon depression of the gripping members 26 , 28 , the breaking tabs 36 , 38 flex the body 12 inwardly, thereby localizing the forces effected by squeezing the members 26 , 28 toward one another and enhancing fracturing of the ampule 14 as more fully described below.
In the preferred embodiment, the liquid applicator 10 of the present invention is constructed to house a 3 ml ampule. It will be understood and appreciated, however, that ampules of various sizes may be utilized and such is contemplated to be within the scope of the present invention. In the 3 ml embodiment, the distance between the lateral line defined by the most downwardly positioned portion of flange 24 , and the fracturing structure is approximately 1.0 inches. It will be understood and appreciated, however, that this distance will vary based upon the size of the applicator and ampule utilized. Any such variation is contemplated to employ a similar angular orientation for the gripping members, however. Such variations are contemplated to be within the scope of the present invention.
A porous element 16 such as a sponge or the like closes off the open end 18 of the body 12 . The porous element 16 is received on flange 24 and encloses the ampule 14 within the internal chamber 22 . With reference to FIG. 6, the porous element 16 is formed of felt or an open-celled foam material that is laminated on one side with laminate material 17 . In the preferred embodiment, laminate material 17 is a woven or non-woven polyester material or fabric such as polyethylene. Laminate material 17 of the porous element 16 is positioned between the open-celled foam material and the flange 24 of the body 12 . As such, laminate material 17 functions to prevent shards of glass from the fractured ampule from pushing through the porous element during use of the applicator. In addition, the polyethylene coating provides material at the interface between the flanges 24 of the body 12 and the porous element 16 , and is partially melted during formation of the applicator, as more fully described below.
The preferred porous element 16 is cut from a sheet of sponge material having the desired porosity for the liquid to be dispensed, whereby liquid is prevented from flowing immediately through the element 16 when the ampule 14 is fractured. In other words, once an ampule 14 is fractured, the released liquid saturates the element 16 and flows from the element 16 only as the surface absorbs the liquid from the saturated element 16 . Consequently, the body 12 essentially functions as a reservoir of the desired liquid. The porous element 16 is preferably generally circular in shape although it will be appreciated that the element may be of any desired size and shape which is capable of being supported on the flange 24 .
During formation of the applicator, the ampule 14 is inserted into the internal chamber 22 of the body 12 . Thereafter, the porous element 16 is secured to the body 12 of the applicator by welding the laminate material to the flange 24 using an ultrasonic welding operation. The polyester material of the laminate provides suitable welding material that melts together with the material of the flange 24 to secure the porous element 16 in place over the internal chamber 22 and enclose the ampule. 14 . Securing the porous element 16 on the flange 24 in this manner facilitates preventing leakage between the flange 24 and the element 16 . It will be appreciated that other suitable securing expedients could be employed in place of the ultrasonic welding operation. For example, the porous element 16 could be secured in place by an adhesive or stitching, or by heat sealing or chemically bonding the element in place. Such alternative securing expedients are contemplated to be within the scope of the present invention.
The porous element 16 is disposed at an angle, α, such as 45°, with respect to the central longitudinal axis of the body 12 . Thus, the liquid may be released to flow by gravity upon fracture of the ampule 14 to the porous element 16 affixed to the open end 18 of the body 12 . When the applicator is manipulated for scrubbing with the closed, distal end oriented away from the surface to be scrubbed and the porous element oriented toward the surface, the liquid will flow from the fractured ampule under the force of gravity down the body 12 to the open end 18 and through the porous element 16 .
By employing a porous element having a laminate as described herein, numerous advantages are realized. For example, the material presents a physical barrier that resists puncture by glass fragments of the fractured ampule. In addition, the laminate material provides a suitable welding material for securing the porous element in place on the body when an ultrasonic welding operation is used to manufacture the applicator. Further, by providing a relatively simple construction in which the body and porous element are welded together and the gripping members and porous element are disposed as described herein, an applicator is obtained which may be designed for single use, and which enables one-handed operation.
In use, the applicator 10 presents a hand-held liquid applicator that is squeezed to release the desired liquid contained therein for application to a surface. The applicator 10 is designed to be grasped by the user so that the gripping members 26 , 28 are held between the thumb or palm and fingers of one hand of the user, thus allowing for single-handed operation. The ampule 14 is fractured by the user squeezing the gripping members 26 , 28 toward one another. The movement of the members 26 , 28 is transferred by the tabs 36 , 38 to the body 12 to deform the body 12 inwardly and exert discrete localized fracturing forces against the ampule 14 . The gripping members provide a lever action that gains mechanical advantage as the members are squeezed toward one another. Accordingly, if the user has limited gripping strength, or if the wall of the ampule is exceptionally thick, the members ensure fracturing of the ampule.
As shown in FIG. 5, once the members 26 , 28 have been sufficiently squeezed together, the resulting forces fracture the ampule 14 releasing the liquid contained therein. Once the ampule 14 is fractured, liquid flows from the ampule 14 to the body 12 , as best seen in FIG. 6 . If the applicator 10 is held in an orientation relative to the desired surface as shown in FIG. 1, the liquid flows to the proximal end and is absorbed by the porous element 16 . Thereafter, application of the liquid is accomplished by bringing the porous element 16 into contact with the desired surface. The user may then use a painting or scrubbing motion to apply the liquid to the surface. The entire process of fracturing the ampule 14 and applying the liquid to a desired surface is achieved with the use of only one hand of the user.
Constructed and operated as previously described, this invention provides a hand-held liquid applicator of quality construction having a body which may be squeezed from a location remote from the body to fracture an ampule of liquid contained within the body. Further, this invention provides a disposable liquid applicator which permits single-handed operation in order to free the second hand of the user for use in assisting application of the liquid to the desired area. The liquid applicator of the present invention also is simple to construct and assemble and, therefore, may be manufactured more economically than prior art applications.
From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent in the structure.
It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.
Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense. | A liquid applicator for applying a desired liquid to a surface includes an elongated closed ampule formed of a frangible material containing the desired liquid; a flexible elongated hollow body having axially opposed open and closed ends and presenting a central longitudinal axis, the body defining an internal chamber which is adapted to receive the ampule; and a porous element sealed to the body and closing off the open end thereof so that liquid flows through the element when the ampule is fractured. The body includes a pair of diametrically opposed wings projecting therefrom which form gripping members that are spaced from the body and supported for pivoting movement relative thereto. The body also may include structure for fracturing the ampule, the structure being interposed between the body and the gripping members. Upon squeezing the gripping members toward one another, the structure flexes the body inwardly to exert a fracturing force against the ampule. The body also includes a flange protruding from the body at the open end thereof upon which the porous element is supported. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to apparatus and method for thermomechanical pulping of lignocellulosic material, particularly wood chips.
In recent decades, the quality of mechanical pulp produced by thermomechanical pulping (TMP) techniques has been improving, but the rising cost of energy for these energy-intensive techniques imposes even greater incentives for energy efficiency while maintaining quality. The present inventor has already advanced the state of the art as embodied in the Andritz RTS™, RT Pressafiner™, and RT Fibration™, process technologies. He discovered an operating window by which feed material is preheated for a very short residence time at high temperature and pressure, then refined at such high temperature and pressure between opposed discs rotating at high speed. (U.S. Pat. No. 5,776,305). A further improvement was directed to pretreating the feed chips before preheating, by conditioning in a pressurized steam environment and compressing the conditioned chips in the pressurized steam environment. (PCT/US98/14718). Yet another improvement is disclosed in International Application PCT/US2003/022057, where the feed chips discharged from the pretreatment step, are fiberized without fibrillation, for example with a low intensity refiner, before delivery to a high intensity refiner.
The underlying principle in the progression of the foregoing developments has been to distinguish and handle in distinct equipment, the axial fiber separation and fiberization of the chip material, from the fibrillation of the fibers to produce pulp. The former steps are performed in dedicated equipment upstream of the refiner, using low energy consumption that matches the relatively low degree of working and fiber separation, while the high energy consuming refiner is relieved of the energy-inefficient defibering function and can devote all the energy more efficiently to the fibrillation function. This is necessary since the fibrillation function requires even more energy than defibering (also known as defibration)
These developments did indeed improve energy efficiency, especially in systems that employ high-speed discs (i.e., above 1500 rpm for double disc and above 1800 rpm for single disc refiners). However, especially for systems that did not employ high-speed refiners, the long-term energy efficiency was offset to some extent in the short term by the need for more costly or more space-occupying equipment upstream of the primary refiner.
SUMMARY OF THE INVENTION
The object of the invention is to provide a simplified system and method for producing high quality thermomechanical pulps at lower energy consumption. The simplification includes facilitating the supply of lower cost systems capable of accelerated commissioning and start-up.
In essence, the invention achieves significant energy efficiency, even in systems that do not employ a high speed refiner, while reducing the scope and complexity of the equipment needed upstream of the refiner.
This object is achieved by synthesizing the concepts underlying the RTS, RT Pressafiner, and RT Fibration process technologies, and using a simplified equipment train. The equipment for implementing the invention requires only a pressurized screw discharger (PSD) and refiner(s). Significant modifications, however, are required to the PSD and the associated refining process.
The PSD is of the destructuring variety (macerating pressurized screw discharger, or MPSD) with increasing root diameter and plug zone complete with blowback valve (BBV). MPSD inlet pressure may span from atmospheric to about 30 psig, preferably 5-25 psig. This component of the process simulates RT Pressafiner pretreatment.
Higher dilution flow is necessary to maintain nominal refining consistencies, since the MPSD dewaters to higher solids content than conventional PSD screws.
Fiberizing inner plates (inner rings) in the primary refiner are designed to effectively feed and fiberize destructured wood chips. This component of the process is used to simulate RT Fibration.
High-efficiency outer plates (outer rings) in the primary refiner are designed for feeding (high intensity=>minimum energy consumption) or restraining (low intensity=>maximum strength development), or intensity levels between the two extremes, depending on product quality and energy requirements.
In a broad aspect, the invention is directed to a method for thermomechanical refining of wood chips comprising exposing the chips to an environment of steam to soften the chips, macerating and partially defibrating the softened chips in a compression device, feeding the destructured and partially defibrated chips to a rotating disc primary refiner, wherein opposed discs each have an inner ring pattern of bars and grooves and an outer ring pattern of bars and grooves, a substantially completing fiberization (defibration) of the chips in the inner ring and fibrillating the resulting fibers in the outer ring.
The system implementation preferably includes an inner feeding region and an outer working region on the inner ring and an inner feeding region and an outer working region on the outer ring, wherein the working region of the inner ring is defined by a first pattern of alternating bars and grooves, and the feeding region of the outer ring is defined by a second pattern of alternating bars and grooves. The first pattern on the working region on the inner ring has relatively narrower grooves than the grooves of the second pattern on the feeding region on the outer ring. The fiberization of the chips is substantially completed in the working region of the inner ring with low intensity refining, while the fibrillation of the fibers is performed in the working region of the outer ring at a smaller plate gap and higher refining intensity.
The inventive method preferably comprises the steps of exposing the chips to an environment of steam to soften the chips, compressively destructuring and dewatering the softened chips to a consistency greater than about 55%, diluting the destructured and dewatered chips to a consistency in the range of about 30% to 55%, feeding the diluted destructured chips to a rotating disc refiner, where opposed discs each have an inner ring pattern of bars and grooves and an outer ring pattern of bars and grooves, fiberizing (defibrating) the chips in the inner ring, and fibrillating the resulting fibers in the outer ring.
The compressive destructuring, dewatering, and dilution can all be implemented in one integrated piece of equipment immediately upstream of the primary refiner, and the fiberizing and fibrillating are both achieved between only one set of relatively rotating discs in the primary refiner.
The new, simplified TMP refining method, combining a destructuring PSD and fiberizing inner plates, was shown to effectively improve TMP pulp property versus energy relationships relative to conventional TMP pulping.
The method improved the pulp property/energy relationships for three commercially available processes: TMP, RT, and RTS. The RT and RTS refining configurations refer to low retention and higher pressure refining, typically between 75 psig and 95 psig, at standard refiner disc speeds (RT) or higher disc speeds (RTS).
The defibration efficiency of the inner refining zone improved at higher refining pressure. The level of defibration further increased with an increase in refiner disc speed.
Thermomechanical pulps produced with holdback outer rings had higher overall strength properties compared to pulps with expelling outer rings. The latter configuration required less energy to a given freeness and had lower shive content.
The specific energy savings to a given freeness using the inventive method in combination with expelling outer plates was 15%, 22%, and 32% for the TMP, RT, and RTS series, respectively, compared to the control TMP pulps.
Combining the inventive method with bisulfite treatment improved pulp strength properties and significantly increased pulp brightness.
Higher dilution flow effectively compensated for the higher discharge solids exiting the MSD-type PSD. The dilution/impregnation apparatus should ensure thorough penetration of the chips exiting the MPSD. One option is a split dilution strategy that adds dilution to both the MPSD discharge and in-refiner.
In the present context, maceration should be understood as the physical mechanism associated with solid material under compressive shearing forces. Maceration of wood chips in a steam-pressurized screw device or the like, destructures the material without breakage across grain boundaries, resulting in significant but not complete (e.g., up to about 30%) axial separation of the fibers. The majority of the maceration occurs in the plug zone after the flights, but some initial maceration can occur in the flighted section before the plug zone. The restriction in the plug zone can increase compression and maceration to some degree in the earlier flighted section.
Impregnation liquid (water and/or chemicals) is added directly in the expansion region or chamber at the discharge of the macerating screw device such that the liquid uptake into the expanding wood structure is immediate. The destructured wood chips should be sufficiently saturated with liquid such that the refining consistency is in a preferable range for optimum pulp. All or most of the liquid uptake takes place at the discharge of the MPSD as the heavily compressed chips are released. In the alternative embodiment, the dilution liquid is split, with some dilution at the MPSD screw discharge and further dilution introduced between the inner and outer refiner rings. The latter configuration is useful when excessive saturation is observed at the MPSD discharge but additional dilution is beneficial (after the inner rings) to further optimize the fibrillation refining.
As an example but not a limitation, the consistency in the plug-pipe zone is typically in the range of 58%-65%, and in the expansion zone with impregnation/dilution, in the range of about 30%-55%. The material remains at this consistency range through the seal off zone of the BBV (which is not normally a full seal and is thus similar in pressure to the expansion zone), at the exit from the seal off zone, and at the inlet to the refiner ribbon feeder. This is a pressurized environment so vaporization is taking place, but the goal is to target the optimum refining consistency, usually around 35%-55%, as delivered to the refiner feed device for introduction between the refiner plates.
In most cases the bar/grooves in the working zone of the outer rings (fibrillation) must be finer than in the working zone of the inner rings (defibration). To produce a mechanical pulp fiber, the fiber must first be defibrated (separated from the wood structure) and then fibrillated (stripping of fiber wall material). A key feature of this invention is that the working zone of the inner rings primarily defibrates and the working zone of the outer rings primarily fibrillates. A significant aspect of the novelty of the invention is maximizing the separation of these two mechanisms in a single machine and by that more effectively optimizing the fiber length and pulp property versus energy relationships. Since defibration in the inner rings takes place on relatively large destructured chips, the associated working region pattern of bars and grooves cannot be too fine. Otherwise the destructured chips would not adequately pass through the grooves of the inner rings and be distributed evenly. The defibrated material as received in the outer ring feed region from the inner ring and distributed to the outer ring working region, is relatively smaller and thus the pattern of bars and grooves in the working region of the outer ring is finer than in the inner ring. Another benefit of the invention is that more even distribution (i.e., higher fiber coverage across refiner plates) occurs both in the inner rings and outer rings compared to conventional processes. Better feeding means better feed stability, which decreases refiner load swings, which in turn helps maintain more uniform pulp quality.
An important benefit of the present invention is that the retention time is minimized at each functional step of the process. This is possible because the fibrous material is sufficiently size reduced at each step in the process such that the operating pressures can almost instantaneously heat and soften the fiber to the required level. The process can be considered as having three functional steps: (1) producing destructured chips, (2) defibrating the destructured chips, and (3) fibrillating the defibrated material. The equipment configuration should establish minimum retention time from the MPSD discharge of step (1) to the refiner inlet. The refiner feed device (e.g., ribbon feeder or side entry feeder) operates almost instantaneously for initiating step (2) in the inner rings. The inner ring design should establish a retention time for the material to pass through uninhibited. Some inner ring designs may have longer residence than others to effectively defibrate, but the net retention time is still less than if fibration were performed in a separate component. The defibrated material passes almost instantaneously to the outer ring where step (3) is achieved. Here also, the retention time is low. The actual retention time in the outer ring will be dictated by the design of plates chosen to optimize pulp properties and energy consumption. The benefit of this very low retention (minimum) at each process step (while achieving necessary fiber softening for maintaining pulp strength properties) is maximum optical properties.
In the system described in my prior International Application PCT/052003/022057, wherein the destructured chips were defibrated in a smaller fiberizer refiner before delivery to the main, primary refiner for fibrillation, the pressures were much lower in the fiberizing (defibration) step. The fiberizing retention time at pressure was much longer in a completely separate refiner. It was desirable to maintain a lower temperature to help preserve pulp brightness, since the low intensity refining intensity was gentle. High temperatures were therefore neither necessary nor desirable in the separate fiberizing refiner to preserve pulp strength. In the present invention, defibration and fibrillation are performed within the same highly pressurized refiner casing. The refining intensity in the fiberizing (defibrating) inner ring is still low, achieved at high pressure and a low retention time. There is no negative impact on brightness despite the high pressure (temperature), because the retention time is so short. This is analogous to the surprisingly beneficial effect of low preheat retention time at high temperature as described in my U.S. Pat. No. 5,776,305 (RTS mechanism).
When the present invention is implemented in an RTS system, there is no need for a separate preheat conveyor immediately upstream of the refiner feed device, because the destructured chips heat up rapidly during normal conveyance from the MPSD to the refiner. The environment from the expansion volume or chamber to the rotating discs is the refiner operating pressure, e.g., 75 to 95 psig for RTS, and the “retention time” at the corresponding saturation temperature during conveyance between the MPSD and refiner is well under 10 seconds, preferably in the range of 2-5 seconds, corresponding to the preferred RTS preheat retention time.
More generally, the process advantage of achieving energy efficient production of quality TMP pulp with minimum time at each process step, has the corollary advantage of minimizing the component, space, and cost requirements of equipment for implementing the process. Almost any installed TMP, RT-TMP, or RTS-TMP system can be upgraded according to at least some aspects of the present invention, without increasing the equipment footprint in the mill.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic of a TMP refiner system that illustrates an embodiment of the invention;
FIGS. 2A and B are schematics of alternatives of a macerating pressurized screw with dilution injection feature, suitable for use with the present invention;
FIG. 3 is a schematic representation of a portion of a refiner disc plate, showing the inner fiberizer ring and the distinct outer fibrillation ring;
FIGS. 4A and B show an exemplary inner, fiberizing ring pair for the rotor and stator, respectively, having angled bars and grooves;
FIG. 5 shows the relationship of the inner, fiberizing ring pair to the outer, fibrillation ring pair, at the transition region;
FIGS. 6A and B show another exemplary fiberizing ring pair, having substantially radial bars and grooves;
FIGS. 7A and B show an exemplary outer, fibrillating ring, in front and side views, respectively, and FIGS. 7C and D show section views across the bars and grooves in the outer and middle zones, respectively;
FIGS. 8A , B and C show another exemplary outer, fibrillating ring in front and section views, respectively;
FIG. 8D shows a side and front view, respectively, of an exemplary outer ring for a rotor disc, having curved feeding bars;
FIG. 8E shows a side and front view, respectively, of an exemplary opposing outer ring for a stator, to be employed with the outer ring of FIG. 8D ;
FIG. 9 is a schematic of the plate used in laboratory experiments to model and obtain measurements of the operational characteristics inner fiberizing plate;
FIG. 10 is a schematic of the plate used in laboratory experiments to model and obtain measurements of the operational characteristics outer, fibrillating plate;
FIGS. 11-18 illustrate pulp property results for most of the refiner series produced in this investigation;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
1. Overview
FIG. 1 shows a TMP refiner system 10 according to the preferred embodiment of the invention. A standard atmospheric inlet plug screw feeder 12 receives presteamed (softened) chips from source S at atmospheric pressure P 1 =0 psig and delivers pre-steamed wood chips at pressure P 2 =0 psig to a steam tube 14 where the chips are exposed to an environment of saturated steam at a pressure P 3 . Depending on the system configuration, the pressure P 3 can range from atmospheric to about 15 psig or from 15 to up to about 25 psig with holding times in the range of a few seconds to many minutes. The chips are delivered to a macerating pressurized plug screw discharger (MPSD) 16 .
The macerating pressurized plug screw discharger 16 has an inlet end 18 at a pressure P 4 in the range of about 5 to 25 psig, for receiving the steamed chips. Preferably, the MPSD has an inlet pressure P 4 that is the same as the pressure P 3 in the steam tube 14 . The MPSD has a working section 20 for subjecting the chips to dewatering and maceration under high mechanical compression forces in an environment of saturated steam, and a discharge end 22 where the macerated, dewatered and compressed chips are discharged as conditioned chips into an expansion zone or chamber at pressure P 5 where the conditioned chips expand. Nozzles or similar means are provided for introducing impregnation liquid and dilution water into the discharge end of the screw device, whereby the dilution water penetrates the expanding chips and together with the chips forms a refiner feed material in feed tube 24 having a solids consistency in the range of about 30 to 55 percent. Alternatively, especially if no impregnation apart from dilution is required, the dilution can be achieved in a dilution chamber that is connected to but not necessarily integral with the MSD discharge. In this context, maceration or destructuring of the chips means that axial fiber separation exceeds about 20 percent, but there is no fibrillation.
A high consistency primary refiner 26 has relatively rotating discs in casing 28 that is maintained at pressure P 5 , each disc, having a working plate thereon, the working plates being arranged in confronting coaxial relation thereby defining a space which extends substantially radially outward from the inner diameter of the discs to the outer diameter of the discs. Each plate has a radially inner ring and a radially outer ring, each ring having a pattern of alternating bars and grooves. The pattern on the inner ring has relatively larger bars and grooves and the pattern on the outer ring has relatively smaller bars and grooves. A refiner feed device 30 , such as a ribbon feeder, receives the feed material from the dilution region associated with the MPSD (directly or via an intermediate buffer bin) and delivers the material at pressure P 5 to the space between the discs at substantially the inner diameter of the discs. As will be described in greater detail below, the inner ring completes the fiberizing (defibration) of the chip material and the outer ring fibrillates the fibers.
The refiner can be a single disc refiner (one rotating plate faces a stationary stator plate), a double disc refiner (opposed counter-rotating discs), or a Twin disc refiner available from Andritz Inc., Muncy Pa., where a central stator has plates on both sides, and each side faces a rotating disc. The feed devices for a double disc or Twin disc refiner would be somewhat different than that for a single disc refiner, as is known in the relevant field of endeavor.
The system may be backfit into any of the three core processes of (1) typical TMP, (2) RT-TMP, or (3) RTS-TMP. In the typical TMP, the first PSF 12 or rotary valve maintains separation between upstream atmospheric conditions and the elevated pressure in the steam tube that acts as a preheater in the pressure range of about 0-30 psig for a typical hold time of 30 seconds to 180 seconds. As per the invention, the second PSF at the discharge of the steaming tube (typically called a plug screw discharger or PSD) is converted or replaced with an RTPressafiner (macerating pressurized plug screw discharger=MPSD) screw device. In the RT-TMP and RTS-TMP configurations, the first PSF or rotary valve serves essentially the same purpose and the steaming tube can be operated in a range from 0-30 psig. In all configurations the first PSF is not necessary should a mill elect to operate the inlet to the MPSD (RTPressafiner) at atmospheric conditions (0 psig). It is noted that the benefit of pressurizing the inlet during RTPressafiner pretreatment is lost when operating at atmospheric conditions, which can result in fiber damage when processing softwoods using a PSD screw of the destructuring variety. Atmospheric conditions may be satisfactory when processing, for example hardwoods, which have much shorter fiber length to begin with. The typical TMP process is referred to as PRMP when no pressurized presteaming is conducted at the inlet to the MPSD. The material discharging from the MPSD (RTPressafiner) then discharges into the higher temperatures of the refining environment. At RT- or RTS-conditions the refining environment is at a higher temperature, which corresponds to the high pressure (above 75 psig, corresponding to a temperature well above the lignin transition temperature, Tg) in the refiner. In this embodiment, the total time the material is above Tg before delivery to the discs, should be less than 15 seconds, preferably less than 5 seconds.
This can be summarized in the following table:
System Conditions For Invention in Three Backfit Embodiments
Component Conditions
TMP
RT-TMP
RTS-TMP
Pressure P1 @ chip
0
psig
0
psig
0
psig
source S
Pressure P2 @ PSF 12
0-30
psig
0-30
psig
0-30
psig
outlet
Pressure P3 @ steam
0-30
psig
0-30
psig
0-30
psig
tube 14
Holding time steam
30-180
sec
10-40
sec
10-40
sec
tube 14
Inlet pressure P4 @
0-30
psig
0-30
psig
0-30
psig
MPSD 16
Processing time in
<15
sec
<15
sec
<15
sec
MPSD 16
Pressure P5 @
30-60
psig
75-95
psig
75-95
psig
expansion volume 22,
refiner feeder 30 and
casing 28
Dwell time in
<10
sec
<10
sec
<10
sec
expansion volume 22
refiner feeder 30 and
casing 28
FIGS. 2A and B are schematics of a macerating pressurized screw 16 with dilution injection feature, suitable for use with the present invention. According to the embodiment of FIG. 2A , chip material 32 is shown in the central, dewatering portion of working section 20 , where the diameters of the perforated tubular wall 34 , rotatable coaxial shaft 36 , and flights 38 are constant. A chip plug 40 is formed in the plug portion of the working section, immediately following the dewatering portion, where the wall is imperforate and the shaft has no flights but the shaft diameter increases substantially, producing a narrowed flow cross section and thus a high back pressure that enhances the extrusion of liquid from the chips, through the drain holes formed in the wall of the central portion. The constricted flow and macerating effect may be further enhanced or adjusted by use of a tubular constriction insert (not shown) within the imperforate wall, or rigid pins or the like (not shown) projecting from the wall into the plugged material. The plug is highly compressed under mechanical pressures typically in the range of 1000 psi to 3000 psi, or higher. Most if not all of the maceration occurs in the plug. The chips are substantially fully destructured, with partial defibration exceeding about 20 percent usually approaching 30 percent or more.
At the end of the plug, the discharge end 22 of the MPSD has an increased cross sectional area, defined between an outwardly flared wall 42 and the confronting, spaced conical surface 44 of the blow back valve. 46 . The blow back valve is axially adjustable from a stop position nested in a conical recess 48 at the end of the MPSD shaft 36 , to a maximum retracted position. This adjusts the flow area of the expansion zone or volume 50 while maintaining a mild degree of sealing at 52 by chip material between the valve against the outer end of the flared wall, which can be controlled in response to transient pressure differential between the feed tube 24 and the MPSD 16 .
In the expansion zone 50 , impregnating liquor is fed under high pressure either through a plurality of pressure hoses 54 and associated nozzles (as shown), or a pressurized circular ring. The dewatered chips entering the expansion zone 50 quickly absorb the impregnation fluid and expand, helping to form the weak sealing zone at the end of the expansion zone.
FIG. 2B shows an alternative whereby the impregnation in the expansion zone 50 is achieved by providing fluid flow openings 56 in the face of the conical blow back valve, which can be supplied via high pressure hoses through the shaft 58 of the blow back valve.
The feed tube 24 is preferably a vertical drop tube for directing and mixing the diluted chips from the MPSD 16 to the feed device 30 of the refiner. However, it should be understood that the pressure P 5 in the feed tube 24 is the same pressure as in the feed device 30 and refiner casing 28 . A small pressure boost or drop may be desired between the refiner feed device 30 and refiner casing 28 , which is common practice in the field of TMP. Regardless, the pressures throughout this region following the MPSD to the refiner casing would typically be well above 30 psig, usually above 45 psig, which is much higher than the MPSD inlet steam pressure P 4 . However, the plug 40 is so highly mechanically compressed that even with the tube pressure as high as 95 psig or more, the compressed plug will quickly expand in the expansion zone due to the expansion of pores in the fibers in the uncompressed state. It can thus be appreciated that the feed tube can act as an expansion chamber in contributing to the effectiveness of the expansion volume. Practitioners in this field could readily modify the design and relationship of the expansion zone and feed tube so that expansion and dilution occur predominantly in a dedicated expansion chamber that is attached to but not integral with the MPSD.
FIG. 3 is a schematic representation of a portion of refiner disc plate 100 , showing the inner fiberizer ring 102 and the outer fibrillation ring 104 . Each ring can be a distinct plate member attachable to the disc, or the rings can be integrally formed on a common base that is attachable to a disc. Each ring has an inner feeding region 106 , 108 and an outer working region 110 , 112 . The working (defibrating) region of the inner ring is defined by a first pattern of alternating bars 114 and grooves 116 , and the feeding region of the outer ring is defined by a second pattern of alternating bars 118 and grooves 120 . The very course bars 122 and grooves 124 in the feeder region 106 of the inner ring direct the previously destructured chip material into the defibrating region 110 of significantly narrower bars and grooves. The fiberized material then intermixes in and crosses the transition annulus 126 , where it is enters the feed region 108 of the outer ring. In general, the first pattern on the working region 110 on the inner ring has relatively narrower grooves than the grooves of the second pattern on the feeding region 108 on the outer ring. The working (fibrillating) region 112 of the outer ring has a pattern of bars 128 and grooves 130 wherein the grooves 130 are narrower than the grooves 116 of the working region 110 of the inner ring.
The coarse bars and grooves of the feeding region 106 of the inner ring on one disc can be juxtaposed with a feeding region on the opposed disc that has no bars and grooves, so long as the shape of the feed flow path readily directs the feed material from the ribbon feeding device into the working regions 110 of the opposed inner rings. Thus, every inner ring 102 will have an outer, fiberizing region 110 with a pattern of alternating bars and grooves 114 , 116 but the associated inner region 106 will not necessarily have a pattern of bars and grooves. The outer region 112 of the fibrillating ring 104 can have a plurality of radially sequenced zones, such as 132 , 134 , and/or a plurality of differing but laterally alternating fields, in a manner that is well known for the “refining zone” in TMP refiners, such as 136 , 138 . In FIG. 3 , the outer ring 104 has an inner, feeding region 108 of alternating bars and grooves, and the working region 112 has a first pattern of alternating bars and grooves 128 , 130 appearing as laterally repeating trapezoids in zone 132 , and another pattern of alternating bars and grooves 140 , 142 appearing as laterally repeating trapezoids in zone 134 that extend to the circumference 144 of the plate.
The annular space 126 between the inner and outer rings 102 , 104 can be totally clear, or as shown in FIG. 3 , some of the bars such as 146 in the outer ring feed region 108 can extend into the annular space. The annular space 126 delineates the radial dimension of the inner and outer rings, whereby the radial width of the inner ring 102 is less than the radial width of the outer ring 104 , preferably less than about 35 percent of the total radius of the plate from the inner edge 148 of the inner ring 102 to the circumferential edge 144 of the outer ring 104 . Also, the radial width of the feed region 106 of the inner ring 102 is larger than the radial width of the working region 110 of the inner ring, whereas the radial width of the feed region 108 in the outer ring 104 is less than the radial width of the working region 112 .
The type of plate described above with reference to FIG. 3 will for convenience be referred to as an “RTF” plate. The destructured and partially defibrated chip material enters the inner feed region 106 where no substantial further defibration occurs, but the material is fed into the working region 110 where energy-efficient low intensity action of the bars and grooves 114 , 116 defibrates substantially all of the material. Such plates can be beneficially used as replacement plates in refiner systems that may not have an associated pressurized macerating discharger. Where a PMSD is present, the combination of full destructuring and partial defibration along with high heat upstream of the refiner allows the plate designer to minimize the radial width and energy usage in the working region 110 of the inner ring for completing defibration. The pattern of bars and grooves 114 , 116 and the width of the working region 110 can be varied as to intensity and retention time. Even with less than ideal upstream destructuring and partial defibration, the plate designer can increase the radial width of the inner working zone 110 and chose a pattern that retains the material somewhat for enhanced working, while still achieving satisfactory fibrillation in a shortened high intensity outer ring 112 and overall energy savings for a given quality of primary pulp. Moreover, the invention does not preclude that with the RTF plates, some defibration may occur in the outer ring 104 or some fibrillation may occur in the inner ring 102 .
The composite plate shown in FIG. 3 is merely representative. FIGS. 4 , and 6 show other possible regions for the inner rings. FIG. 4A shows one inner ring 150 A and FIG. 4B shows the opposed inner ring 150 B. FIG. 5 shows a schematic juxtaposition of opposed inner rings 150 A and 150 B, with portions of the associated outer rings 152 A and 152 B as installed in the refiner. The feed gap 154 of the inner rings is preferably curved to redirect the feed material received at the “eye” of the discs from the axially conveyed direction, toward the radial working gap 156 of the inner rings. Preferably, the feeder bars (very coarse bars) are spaced apart by more than the size of the material in the feed. For example, the smallest of the three dimensions defining the chips (chip thickness) is typically 3-5 mm. This is to avoid severe impact, which results in fiber damage in the wood matrix. In most instances, the minimum gap 154 during operation should be 5 mm. The coarse feeder bars have the sole function of supplying the outer part of the inner ring with adequate feed distribution and should do no work on the chips. The feeder bars are provided on the rotor inner ring, but are not absolutely necessary on the stator inner ring.
In the embodiment of FIG. 4 , the bars and grooves in the inner ring are angled relative to the radius, thereby inhibiting free centrifugal flow in the inner ring and increasing retention time, if rotated to the left, or accelerating the flow if rotated to the right. In the embodiment of FIG. 6 , inner rings 162 A and 162 B have a substantially radial orientation that neither inhibits or nor enhances centrifugal flow. As shown in FIGS. 3 and 5 , the bars at the inlet of the defibrating region, e.g. the outer region of the inner rings, have a long chamfer 164 , or a gradual wedge closing shape. In general, the entrance to the fiberizing gap 156 between the inner rings is radial or near radial (no significantly scattered transition). This also prevents strong impacts on the wood chips. The slope of the chamfer should be typically a drop of 5 mm in height over a radial distance of 15-50 mm. The resulting slope is 1:5 to 1:10, but slopes of 1:3-1:15 with height drop of 3 to 10 mm are acceptable. It is that wedge shape that defines the low intensity “peeling” of chips, as opposed to the high intensity impacts of conventional breaker bars operating at a tight gap. The operating gap 156 in the working region of the inner plate be in the order of 1.5-4.0 mm, and can narrow gently outwardly. If the chamfer 164 is in the lower range of the angle (e.g. 1:3), then a large taper of gap 156 should be used, e.g., at least 1:40. This will ease the feed into the tighter gap.
The short working region 110 should operate at a gap of between 3 and 5 mm when the outer rings are at a standard operating gap. The gap 158 at the inlet of the outer rings should be slightly larger than the gap at the outer part of the inner rings. The outer part of the inner ring is preferably ground with taper, which ranges from flat to approximately 2 degrees, depending on application. Larger tapers and larger operating gaps will reduce the amount of work done in the inner rings. The construction of the outer region of the inner ring is such that it should minimize impact on the feed material in order to preserve fiber length at a maximum, while properly separating fibers.
The groove width in the fibrating region 110 should be smaller than the wood particles, and in order of magnitude of minimum operating gap for the fibrating region. Typically, no groove should be wider than 4 mm wide. This ensures that wood particles are being treated in the gap rather than being wedged between bars and hit by bars from opposing disc.
In the fibrating inner region 110 (or plate inlet for a one-piece refiner plate), the chips are reduced to fibers and fiber bundles before passing through annular space 160 and entering the outer ring 104 . That ring can closely resemble known high consistency refiner plate construction. As the fibers are mostly separated, they will not be subjected to high intensity impacts. One can see from FIGS. 3 and 5 that if untreated chips could enter the feeder region 108 of the outer ring, they would be subjected to high intensity impacts when the chip is wedged between two coarse bars 118 , 120 . If the chips are properly separated in the fibrator inner rings 102 , then there are no large particles left, so they cannot be subjected to this type of action.
The division of functionality as between the inner and outer rings can also be implemented in a so-called “conical disc”, which has a flat initial refining zone, followed by a conical refining zone within the same refiner. In that case, the inventive fibrating rings would substitute for the flat refining zone, which would then be followed by the conventional “main plate” refining in the conical portion. Normally, a conical portion for such refiners has a 30 or 45 degree angle cone, e.g. it is 15 or 22.5 degrees from a cylindrical surface. An example of such a conical disc refiner is described in U.S. Pat. No. 4,283,016, issued Aug. 11, 1981. Thus, as used herein, “disc” includes “conical disc” and “substantially radially” includes the generally outwardly directed but angled gap of a conical refiner.
The inlet of the outer region of inner ring has a radial transition, or close to radial. Large variation in the radial location of the start of the ground surface normally results in the loss of fiber length, when particles larger than the gap are quickly forced into the gap. With a long chamfer at the start of the region (longer is better), the material fed will be gradually reduced in size until small enough (coarseness reduction) to enter the gap formed by the ground surfaces. The groove width of the outer region of the inner ring has to be narrow enough to prevent large unsupported fiber particles from entering the groove and then be forced into the gap, thus causing fiber cutting. Typically, the groove width should be no wider than the gap at the inlet of the ground surface. Subsurface dams or surface dams can be used in order to increase the efficiency of the action and/or increase energy input in the inner plates.
Two embodiments of the outer, fibrillating ring are shown in FIGS. 7 and 8 . These can range from high intensity to very low intensity. For the purpose of illustration of the concept, the pattern of FIG. 7 is a typical example of a high intensity directional outer ring 166 . FIG. 8 represents a very low intensity bi-directional design 182 . Various other bar/groove configurations can be used, such as having a variable pitch (see U.S. Pat. No. 5,893,525).
The directional ring 166 is coarser and has a forward feeding region 172 which reduces retention time and energy input capability in that area, forcing more energy to be applied in the outer part of the ring, which in turn increases the intensity of the work applied there, and thus will operate at a tighter gap. The working region of the outer ring has two zones 168 , 170 , the outer 168 of which has finer grooves than the former 170 . Some or all of the grooves such as 176 in the zone 168 can define clear channels that are slightly angle to the true radii of the ring, whereas other grooves such as 180 in the other zone 170 can have surface or subsurface dams 174 , 178 . Overall, the outer ring 166 is similar to the outer ring 112 of FIG. 3 .
As another example, the full-length variable pitch pattern 182 of FIG. 8 has essentially radial channels, without any centrifugal feeding angle. The feed region 190 is very short, and the working region 188 can have uniform or alternating groove width, or as shown at 184 and 186 , alternating or variable groove depth. This allows for a longer retention time within the plates and, combined with the large number of bar crossings, allows for a low intensity of energy transfer, which results in a larger plate gap.
In a variation of the outer ring, the inner feeding region of the outer ring is designed to prevent backflow of fiber from the outer ring to the inner ring. FIG. 8D presents an outer ring 192 for the rotor disc, with a feed region 194 having curved feeding bars 195 . The opposing stator ring 196 , as illustrated in FIG. 8E , does not have bars in the inner feed region 198 in opposition to the curved bars, thereby accommodating the opposing curved feeding bars 195 on the outer ring 192 . Such an approach further ensures a complete separation between the defibration and fibrillation steps in the inner and outer rings, respectively.
As shown in figures, the curved feeding (injector) bars 195 can optionally be supplemented with other structure in the feeding region of the rotor and/or stator rings (such as pyramids and opposed radial bars) to aid in the distribution of material from the curved bars into the working region. Thus, the surface of the radial extent of feed region 194 of the rotor can be fully or partially occupied by projecting curved bars 195 and the surface of the radial extent of the feed region 198 of the stator can be entirely flat, or partially occupied by distribution structure. The curved bars 195 of the rotor ring project in the feed region 194 a distance greater than the height of the bars in the working region, but the flatness of the opposed surface in the feeding region 198 of the stator ring accommodates this greater height.
In general, the pattern of bars and grooves throughout the working region of the inner ring has a has a first average, preferably uniform, density and the pattern of bars and grooves throughout the feed region of the outer ring has a second average, preferably uniform but lower density.
2. Pilot Plant Laboratory Realization
The combination of fiberizing inner rings and high-efficiency outer rings is therefore an important component of this process. The optimization of this process was conducted by running an Andritz pressurized 36-1CP single disc refiner in two steps, firstly using only inner plates and secondly using only the outer plates. For the inner plates, a special Durametal D14B002 three zone refiner plate was used with ½ of the outer intermediate zone and the entire outer zone ground out (see FIG. 9 ). The inner ½ of the intermediate zone is used to fiberize the destructured wood chips. For the outer plate, a Durametal 36604 directional refiner plate was used in both feeding (expel) and restraining (holdback) refining configurations (see FIG. 10 ).
Three refining configurations were run using the fiberizer plate inners to simulate the following process variations:
1. RT [2-3 sec. retention (i), 85 psig, 1800 rpm] ii) See A1 from data tables. 2. RTS [2-3 sec. retention (i), 85 psig, 2300 rpm] ii). See A2 from data tables. 3. TMP [2-3 sec. retention (i), 50 psig, 1800 rpm] iii). See A3 from data tables. i) Retention from PSD discharge to refiner Inlet. ii) Steaming Tube Pressure=5 psi, retention=30 seconds. iii) Steaming Tube Pressure=20 psi, retention=3 minutes.
The precursor used to represent the combination of MPSD destructuring and fiberizing inner plates is f-. Therefore the nomenclature used for the preceding configurations are:
1) f-RT 2) f-RTS 3) f-TMP
The fiberized (f) material was then refined using the refiner plate outers at similar respective conditions of pressure and refiner speed i.e.
1) f-RT outers: 85 psig, 1800 rpm 2) f-RTS outers: 85 psig, 2300 rpm 3) f-TMP outers: 50 psig, 1800 rpm
The majority of the specific energy was applied during the refiner outer runs. Different conditions of refiner plate direction (expel and holdback) and applied power were evaluated during the outer runs in this investigation.
Each of the primary refined pulps was then refined in a secondary atmospheric Andritz 401 refiner at three levels of applied specific energy.
Control TMP series were also produced without destructuring of the wood chips in the PMSD. This was accomplished by decreasing the production rate of the inners control run from 24.1 ODMTPD to 9.4 ODMTPD. This effectively reduced the plug of chips in the PMSD. The plates were backed off during the control inners run such that size reduction was accomplished using only the breaker bars i.e., no effective refining action by the refiner fiberizing bars following the breaker bars. The inners chips were then refined in the 36-1CP refiner using the outers plates. The primary refined pulps were then refined in the Andritz 401 refiner at several levels of specific energy.
TABLE A presents the nomenclature for each of the refiner series produced in this trial study. The corresponding sample identifications are also presented.
TABLE A
Sample Identification
Primary
Primary
Nomenclature *
Inners
Outers
Secondary
f-RT 1800 hb 485 ml
A1
A4
A7, A8, A9
f-RT 1800 ex 663 ml
A1
A5
A10, A11, A12
f-RT 1800 ex 661 ml
A1
A6
A13, A14, A15
f-RT 1800 ex 460 ml
A1
A16
A22, A23, A24
f-RT 1800 ex 640 ml
A1
A17
A25, A26, A27
(2.8% NaHSO 3 )
f-RT 1800 hb 588 ml
A1
A18
A28, A29, A30
f-RTS 2300 ex 617 ml
A2
A19
A31, A32, A33
f-RTS 2300 ex 538 ml
A2
A20
A34, A35, A36
(3.1% NaHSO 3 )
f-TMP 1800 ex 597 ml
A3
A21
A37, A38, A39
f-TMP 1800 hb 524 ml
A3
A41
A46, A47, A48
TMP 1800 hb 664 ml
A3-1
A44
A54, A55, A56,
A57, A58
TMP ** 1800 hb 775 ml
A3-1
A43
A49, A50, A51,
A52, A53
* Nomenclature = process, 1ry refiner speed (1800 rpm or 2300 rpm), 1ry outers configuration (ex or hb), 1ry refined freeness
** No good since primary refiner freeness was too high.
The refiner series produced with the primary outers in holdback had a larger plate gap and higher long fiber content than the respective series produced using expelling outers. This permitted refining the holdback series to lower primary freeness levels while retaining the long fiber content of the pulp.
FIGS. 11-18 illustrate pulp property results for most of the refiner series produced in this investigation. The two series produced at very low primary freeness (<500 ml) are excluded from the plots due to congestion.
FIG. 11 . Freeness Versus Specific Energy
The control TMP series had the highest specific energy requirements to a given freeness. The f-TMP series had the next highest energy requirements followed by the f-RT series. The f-RTS series had the lowest specific energy requirements to a given freeness.
TABLE B compares the specific energy requirements for each of the plotted refiner series at a freeness of 150 ml. The results are from linear interpolation.
TABLE B
Specific Energy at 150 ml.
Specific
Energy (kWh/MT)
f-RT 1800 ex 661 ml
1889
f-RT 1800 hb 588 ml
1975
f-RTS 2300 ex 617 ml
1626
f-TMP 1800 ex 597 ml
2060
f-TMP 1800 hb 524 ml
2175
TMP 1800 hb 664 ml
2411
f-RT 1800 ex 640 ml (2.8% NaHSO 3 )
2111*
f-RTS 2300 ex 538 ml (3.1% NaHSO 3 )
1411*
*By extrapolation.
The f-RTS 2300 ex series (combination of fiberizing, RTS, and high intensity plates) had a 32% lower energy requirement than the control TMP series to freeness of 150 ml. The f-RT 1800 hb and f-RT 1800 ex series had 18% and 22%, respectively, lower energy requirements than the control TMP series at 150 ml. The f-TMP hb and f-TMP ex series had 10% and 15%, respectively, lower energy requirements than the control TMP series. The results indicate that rebuilding/replacing the PSD and refiner plates can generate a substantial return on investment for existing TMP systems.
FIG. 12 . Tensile Index Versus Specific Energy
The f-RTS ex pulps had the highest tensile index at a given application of specific energy, followed by the f-RT series and then the f-TMP series. The control TMP pulps had the lowest tensile index at a given application of specific energy.
The addition of approximately 3% sodium bisulfite (NaHSO 3 ) solution to the PSD discharge increased the tensile index relative to the respective series without chemical treatment.
A 52.5 Nm/g tensile index was achieved with the f-RTS 2300 ex (3.1% NaHSO 3 ) series with an application of 3.1% NaHSO 3 and 1754 kWh/ODMT.
FIG. 13 . Tensile Index Versus Freeness
Non-Chemically Treated Series
There were two bands of tensile index results. The lower band represents the series produced using the expelling outer plates. The upper band represents the series produced using the holdback outer plates. The average increase in tensile index using the holdback plates was approximately 10%. It is noted that an f-RTS hb series was not conducted in this trial due to a shortage of fiberized A3 material.
Bisulfite Treated Series
The addition of approximately 3% bisulfite to the f-RT ex and f-RTS ex series elevated the tensile index to a similar or higher level than the holdback pulps.
TABLE C compares each of the refiner series at a freeness of 150 ml. The regression equations used in the interpolations are included on FIG. 13 .
TABLE C Tensile Index at 150 ml Tensile Index (Nm/g) f-RT 1800 ex 661 ml 43.8 f-RT 1800 hb 588 ml 47.7 f-RTS 2300 ex 617 ml 42.4 f-TMP 1800 ex 597 ml 43.5 f-TMP 1800 hb 524 ml 48.1 TMP 1800 hb 664 ml 48.2 f-RT 1800 ex 640 ml (2.8% NaHSO 3 ) 47.0* f-RTS 2300 ex 538 ml (3.1% NaHSO 3 ) 47.9* *By extrapolation. FIG. 14 . Tear Index Versus Freeness
The refiner series produced using holdback outer plates had the highest tear index and long fiber content.
TABLE D compares the refiner series at a freeness of 150 ml. The tear index values were obtained using linear interpolation.
TABLE D
Tear Index at 150 ml
Tear Index
(mN · m 2 /g)
f-RT 1800 ex 661 ml
9.0
f-RT 1800 hb 588 ml
9.9
f-RTS 2300 ex 617 ml
8.7
f-TMP 1800 ex 597 ml
8.6
f-TMP 1800 hb 524 ml
9.3
TMP 1800 hb 664 ml
9.1
f-RT 1800 ex 640 ml (2.8% NaHSO 3 ) *
9.7
f-RTS 2300 ex 538 ml (3.1% NaHSO 3 ) *
8.8
* By extrapolation.
The f-RT hb pulps had the highest tear index. The f-RT ex and f-RTS ex pulps had comparable tear index results
FIG. 15 . Burst Index Versus Freeness
The f-RT 1800 hb and f-TMP 1800 hb series produced with holdback outer plates had the highest burst index at a given freeness. The refiner series produced with expelling outer plates, f-RT 1800 ex, f-TMP 1800 ex, f-RTS 2300 ex, had a lower burst index at a given freeness.
The addition of approximately 3% bisulfite increased the burst index of the series produced with expelling outer plates to a similar level as the non-chemically treated series produced with holdback outer plates.
TABLE E compares the burst index results interpolated to a freeness of 150 ml.
TABLE E Burst Index at 150 ml Burst Index (kPa · m 2 /g) f-RT 1800 ex 661 ml 2.51 f-RT 1800 hb 588 ml 2.85 f-RTS 2300 ex 617 ml 2.30 f-TMP 1800 ex 597 ml 2.38 f-TMP 1800 hb 524 ml 2.76 TMP 1800 hb 664 ml 2.45 f-RT 1800 ex 640 ml (2.8% NaHSO 3 ) * 2.98 f-RTS 2300 ex 538 ml (3.1% NaHSO 3 ) * 2.67 * By extrapolation. FIG. 16 . Shive Content Versus Freeness
The control TMP pulps had the highest shive content levels. The refiner series produced with the expelling outer plates had lower shive content levels than the respective series produced with holdback outer plates. It was clearly evident that the f-pretreatment helps reduce shive content.
TABLE F compares the shive content levels for each refiner series interpolated to a freeness of 150 ml.
TABLE F
Shive Content at 150 ml.
Shive
Content (%)
f-RT 1800 ex 661 ml
0.70
f-RT 1800 hb 588 ml
1.35
f-RTS 2300 ex 617 ml
0.31
f-TMP 1800 ex 597 ml
0.37
f-TMP 1800 hb 524 ml
1.61
TMP 1800 hb 664 ml
2.63
f-RT 1800 ex 640 ml (2.8% NaHSO 3 ) *
0.59
f-RTS 2300 ex 538 ml (3.1% NaHSO 3 ) *
0.18
* By extrapolation.
The f-RTS ex series produced with and without bisulfite addition had the lowest shive content levels. The addition of bisulfite lowered the shive content.
FIG. 17 . Scattering Coefficient Versus Freeness
The refiner series produced with the expelling outer plates had the highest scattering coefficient levels.
TABLE G presents the scattering coefficient results for each series at a freeness of 150 ml.
TABLE G
Scattering Coefficient versus Freeness
Scattering
Coefficient (m 2 /kg)
f-RT 1800 ex 661 ml
57.1
f-RT 1800 hb 588 ml
55.1
f-RTS 2300 ex 617 ml
56.8
f-TMP 1800 ex 597 ml
56.3
f-TMP 1800 hb 524 ml
53.6
TMP 1800 hb 664 ml
54.4
f-RT 1800 ex 640 ml (2.8%
55.9
NaHSO 3 ) *
f-RTS 2300 ex 538 ml (3.1%
53.8
NaHSO 3 ) *
* By extrapolation.
The addition of approximately 3% bisulfite reduced the scattering coefficient by approximately 1-3 m 2 /kg.
FIG. 18 . Brightness Versus Freeness
All the f-series had higher brightness than the control TMP pulps.
TABLE H compares each of the refiner series interpolated to a freeness of 150 ml.
TABLE H
ISO Brightness at 150 ml
ISO Brightness
f-RT 1800 ex 661 ml
52.0
f-RT 1800 hb 588 ml
51.3
f-RTS 2300 ex 617 ml
52.8
f-TMP 1800 ex 597 ml
49.4
f-TMP 1800 hb 524 ml
48.9
TMP 1800 hb 664 ml
47.3
f-RT 1800 ex 640 ml (2.8% NaHSO 3 ) *
56.5
f-RTS 2300 ex 538 ml (3.1% NaHSO 3 ) *
59.1
* By extrapolation.
The f-TMP series had approximately 2% higher brightness than the control TMP series. A higher removal of wood extractives from the high compression PSD component of the f-pretreatment most probably contributed to the brightness increase.
The f-RTS series had the highest brightness (52.8) followed by the f-RT series (average=51.7), then the f-TMP series (average=49.2).
The addition of 3% bisulfite increased the brightness considerably, up to 59.1 with the f-RTS ex series.
3. Comparing Defibration Conditions During Inner Zone Refining
TABLE I compares the fiberized properties following the inner plates. As indicated earlier, three fiberizer runs, A1, A2, A3 were conducted to simulate the f-RT, f-RTS and f-TMP configurations. Each of these inner ring runs was fed with destructured chips from the PSD.
TABLE I
Fiberized Properties following Inner Rings
Specific
Energy
Shive
+28
Fiberizer
Pressure
Throughput
(kWh/
Content
Mesh
(f-) Run
Process
(psi)
(ODMTPD)
ODMT)
(%)
(%)
A1
RT
85
23.3
152
66.5
75.4
A2
RTS
85
23.3
122
35.6
79.4
A3
TMP
50
24.1
243
88.7
82.4
It is evident that the process conditions have a major impact on the defibration efficiency during inner zone refining. The destructured chips refined at higher pressure (A1, A2) had a significantly lower shive content (=more defibrated fibers) compared to refining at a typical TMP pressure (50 psi). The energy requirement for defibration was also lower at high pressure. The highest defibration level was obtained when combining high pressure and high speed (A2).
The A2 (f-RTS) material demonstrated the highest fiber separation, followed by the A1 (f-RT) material. The A3 (f-TMP) was clearly the coarsest of the fiberized samples.
It is noted that bar directionality was not a factor during the inner zone refining runs since the inner plates were bidirectional.
The energy for defibration decreases with an increase in pressure. The energy losses are quite substantial when defibrating at conventional conditions. For example, at a pressure of 50 psig, an additional specific energy requirement of well over 100 kWh/MT would be necessary when producing fiberized material to the same shives level as compared to refining at 85 psig.
4. Laboratory Procedures
White spruce chips from Wisconsin were used for these examples. Material identification, solids content and bulk density for the spruce chips appear in TABLE II.
Initially, several runs were carried out on the 36-1CP pressurized variable speed refiner utilizing plate pattern D14B002 with the outer zone and ½ intermediate zone ground out. This was conducted to simulate the inner rings of larger single disc refiners. The first run A1 was produced with 30-second presteam retention in the steaming tube at 0.4 bar, 5.87 bar refiner casing pressure, and a machine speed of 1800 rpm. For A2, the machine speed was increased to 2300 rpm. The A3 run was produced with 3 minutes presteam retention at 1.38 bar, 3.45 bar refiner casing pressure, and refiner disc speed of 1800 rpm. Run A3-1 was also conducted at similar conditions as A3, except the production rate was decreased from 24.1 ODMTPD to 9.4 ODMTPD in order to prevent destructuring of the chips prior to feeding the refiner. The plate gap for this run was also increased to eliminate any effective action by the intermediate bar zone, such that the chips received breaker bar treatment only. Fiber quality analysis was not possible on sample A1-1 since chips receiving breaker bar treatment only are not in a fiberized form; therefore shive or Bauer McNett analysis is not applicable.
Each of these pulps was used to produce additional series. Six series were carried out on the A1 material. The outer plates (Durametal 36604) were installed in the 36-1CP refiner to simulate the outer zone of refining. All six primary outer zone runs were refined on the 36-1CP at 5.87 bar casing pressure and at a disc speed of 1800 rpm. The process nomenclature for these runs is RT. A sodium bisulfite liquor was added to A17 resulting in a chemical charge of 2.8% NaHSO 3 (on O.D. wood basis). Three secondary refiner runs were produced on each series.
Two series were produced on the A2 material. Both 36-1CP outer zone runs produced (A19 and A20) were produced at 5.87 bar refiner casing pressure and 2300 rpm machine speed. The process nomenclature for these runs is RTS. Sodium bisulfite liquor was added to A20 (3.1% NaHSO 3 ). Again three secondary refiner runs were produced on each.
Several series were also produced on the A3 material, each at 3.45 bar refiner casing pressure and 1800 rpm. Three secondary refiner runs were produced on each. The process nomenclature for these runs is TMP.
Two control TMP series were produced (A43 and A44) on the A3-1 chips, which went through breaker bar treatment only during inner zone refining. Both A43 and A44 were refined at 3.45 bar steaming pressure and 1800 rpm machine speed. Several atmospheric refiner runs were then conducted on these pulps to decrease the freeness to a comparable range as the earlier produced series.
All pulps were tested in accordance with standard Tappi procedures. Testing included Canadian Standard Freeness, Pulmac Shives (0.10 mm screen), Bauer McNett classifications, optical fiber length analyses, physical and optical properties.
TABLE I-A
GRAPHIC RUN SUMMARY
NOTE:
A1 USED D14B002 PLATES- OUTER TAPER AND ½ INTERMEDIATE ZONE AND OUTER ZONE GROUND OUT. A1 TUBE PRESSURE OF 0.69 BAR, A4, A5, A6, A16, A17 and A18 TUBE PRESSURE 0.34 BAR. A5, A6, A16 and A17 REFINED IN REVERSE MODE.
TABLE I-B
GRAPHIC RUN SUMMARY
NOTE:
A2 AND A3 USED D14B002 PLATES OUTER TAPER AND ½ INTERMEDIATE ZONE AND OUTER ZONE GROUND OUT. A2 TUBE PRESSURE OF 0.69 BAR, A3 TUBE PRESSURE 1.38 BAR. A19, A20, A21, A40, A41 and A42 TUBE PRESSURE 0.34 BAR. A19, A20, A21 REFINED IN REVERSE MODE.
TABLE I-C
GRAPHIC RUN SUMMARY
TABLE II
MATERIAL IDENTIFICATION
BULK
DENSITY
(kg/m 3 )
MATERIAL
% O.D. SOLIDS
WET
DRY
01
SPRUCE
66.5
169.8
112.9
SOAKED
47.7 | A system and method for thermomechanical refining of wood chips comprises preparing the chips for refining by exposing the chips to an environment of steam to soften the chips, compressively destructuring and dewatering the softened chips to a solids consistency above 55 percent, and diluting the destructured and dewatered chips to a consistency in the range of about 30 to 55 percent. The destructuring partially defibrates the material. This diluted material is fed to a rotating disc primary refiner wherein each of the opposed discs has an inner ring pattern of bars and grooves and an outer ring pattern of bars and grooves. The destructured and partially defibrated chips are substantially completely defibrated in the inner ring and the resulting fibers are fibrillated in the outer ring. The compressive destructuring, dewatering, and dilution can all be implemented in one integrated piece of equipment immediately upstream of the primary refiner, and the fiberizing and fibrillating are both achieved between only one set of relatively rotating discs in the primary refiner. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the discovery of compounds and their use in the selective control of blue-green algae, also referred to as cyanobacteria, (Cyanochloronta) in managed bodies of water, and deals particularly with the use of certain derivatives of 9,10-anthraquinone for such a purpose.
Geosmin and 2-methylisoborneol (MIB) are released into the pond water from producing species of cyanobacteria, and these compounds are quickly absorbed into the adipose tissue of catfish. Producers must hold catfish that are determined to be off-flavor by trained individuals at processing plants until they are deemed to be “on-flavor.” These delays in harvest can last for several days or weeks depending upon the lipid content of the catfish, water temperature, and severity and longevity of the musty off-flavor episode in the production pond. Such delays result in economic losses to the producer due to: 1) additional feed costs; 2) interference with cash flow; and 3) the potential loss of diseased fish due to disease and predation.
Use of the instant invention is for the control of 2-methylisoborneol in water for the elimination of musty off-flavor in water and catfish raised in it. This condition costs the catfish industry up to $60 million dollars annually. The active agents do not kill off green algae at dosing concentration but are focal in their effect on blue-green algae. This allows for the maintenance of a more stable group (non-bloom forming) of diverse planktonic organisms which makes problems involving oxygen depletion and the build up of ammonia resulting from die-offs of the blue-green algae more subject to controlled management.
2. Description of the Prior Art
There are numerous chemical agents that are known to either kill or inhibit blue-green algae growth but each possess aspects limiting their usefulness with catfish rearing. Several agents kill all algae species and cause the creation of negative growth conditions, such as the development of low oxygenation conditions and a rise in ammonia concentrations when used. It is also common knowledge that several compounds must be applied at rates that are toxic not only to algae but also to fish. Another problem is that many compounds tend to persist in the aqueous environment for excessive periods of time. The closest prior art of which the applicants are aware is a publication by Schrader et al. entitled “Selective Growth Inhibition of the Musty-Odor Producing Cyanobacterium Oscillatoria cf. chalybea by Natural Compounds;” Bull. Environ. Contam. Toxicol. (1998)60:651-658 in which it is disclosed that 9,10-anthraquinone has potent activity toward Oscillatoria perornata , however insolubility in water precluded its usage to control Oscillatoria perornata in catfish ponds.
One of the management practices used by producers to prevent musty off-flavor episodes involves the application of algicides to fish ponds in order to kill or help prevent the growth of undesirable cyanobacteria. Copper sulfate, chelated-copper compounds, and the herbicide diuron are currently the only compounds approved by the United States Environmental Protection Agency (USEPA) for use in food-fish production ponds as algicides. In 1999, catfish farmers were granted an emergency exemption by the USEPA and United States Food and Drug Administration to permit the use of diuron as an algicide in catfish aquaculture ponds. However renewal of the exemption must occur annually and is not assured. Unfortunately, these algicides have the following undesirable characteristics: 1) broad-spectrum toxicity towards phytoplankton can result in the death of the entire phytoplankton community and subsequent water quality deterioration leading to the death of catfish; 2) long persistence of the compounds in the environment creates concerns about environmental safety; and 3) the public's negative perception of the use of synthetic herbicides (C. S. Tucker, Off-flavor problems in aquaculture. Rev. Fish. Sci. (2000), vol. 8, pp. 45-88).
Green algae (division Chlorophyta) are the preferred type of phytoplankton over cyanobacteria in catfish production ponds for several reasons (H. W. Paerl and C. S. Tucker, Ecology of blue-green algae in aquaculture ponds. J. World Aquacult. Soc. (1995), vol. 26, pp. 109-131), including the following: 1) green algae have never been linked to off-flavor problems in farm-raises catfish; 2) green algae provide a more substantial base for aquatic food chains than cyanobacteria; 3) green algae are better oxygenators of the water than cyanobacteria; and 4) certain types of cyanobacteria can produce toxins and, in one case, have been implicated in causing the deaths of farm-raised catfish. The discovery of environmentally-safe, selective algicides that help prevent the growth of cyanobacteria responsible for causing musty off-flavor in pond-cultured catfish would greatly benefit the catfish aquaculture industry.
Previous research (K. K. Schrader, M. Q. de Regt, P. D. Tidwell, C. S. Tucker and S. O. Duke, Selective growth inhibition of the musty-odor producing cyanobacterium Oscillatoria cf. chalybea by natural compounds. Bull. Environ. Contam. Toxicol. (1998a), vol. 60, pp. 651-658) has identified several natural compounds from plants that are selectively toxic towards O. perornata . Of these compounds, 9,10-anthraquinone has a high degree of selective toxicity towards O. perornata in the laboratory and inhibits photosynthesis (K. K. Schrader, F. E. Dayan, S. N. Allen, M. Q. de Regt, C. S. Tucker, and R. N. Paul, Jr., 9,10-Anthraquinone reduces the photosynthetic efficiency of Oscillatoria perornata and modifies cellular inclusions. Int. J. Plant Sci. (2000), vol. 161(2), pp. 265-270). Pond efficacy testing of 9,10-anthraquinone dissolved in ethanol (anthraquinone is insoluble in water) using limnocorrals (K. K. Schrader, C. S. Tucker, M. Q. de Regt and S. K. Kingsbury, Evaluation of limnocorrals for studying the effects of phytotoxic compounds on plankton and water chemistry in aquaculture ponds. J. World Aquacult. Soc. (2000), vol. 31, pp. 403-415) did not effectively reduce numbers of O. perornata or reduce MIB levels compared to positive laboratory results (unpublished observations). Additional pond efficacy testing of several different formulations of 9,10-anthraquinone (e.g., incorporation with hydoxypropylmethyl-cellulose or HPMC; Tween 80 and canola oil emulsion) to maintain sufficient phytotoxic levels, determined by laboratory tests, of anthraquinone towards O. perornata in the water column also did not produce positive results (unpublished observations).
While various methodologies for the control of blue-green algae exist, there remains a need for the creation of alternate viable and cost-effective compounds for the selective control of blue-green algae without causing the creation of negative side effects for fish.
SUMMARY OF THE INVENTION
We have now discovered that certain 9,10-anthraquinone derivatives were developed which possess potent activity against O. perornata while possessing a sufficiently high level of solubility in water to make their activity against O. perornata viable. These compounds possess a high level of activity against O. perornata yet are relatively non-toxic to green algae and fishes. The compounds also possess a relatively short half-life in the pond water.
In accordance with this discovery, it is an object of the invention to provide compounds possessing a high degree of selective activity against blue-green algae while being physiologically tolerated by catfish and green algae.
Another object is to provide methods of selectively eliminating blue-green algae which produce geosmin and 2-methylisoborneol while being tolerated by fish and green algae.
Another object is to provide methods of controlling algae in managed bodies of water that are destined for public use or consumption.
Other objects and advantages of the invention will become readily apparent from the ensuing description.
DETAILED DESCRIPTION OF THE INVENTION
It has been found that novel derivatives of 9,10-anthraquinone that were synthesized in the laboratory are effective in controlling certain species of cyanobacteria. In addition, the novel derivatives of 9,10-anthraquinone can control and reduce the cyanobacteria that are responsible for contributing to off-flavor in commercially-raised fish and in fresh water, and these derivatives can improve the water quality of aquaculture and fresh water supplies.
These were screened in the laboratory by the method of Schrader et al. (K. K. Schrader, M. Q. de Regt, C. S. Tucker and S. O. Duke, A rapid bioassay for selective algicides. Weed Technol. (1997), vol. 11, pp. 767-774) for algicidal activity.
The compounds of the present invention are those of the following structure and can be best represented as either 1 or 2 substituted derivatives of 9,10-anthraquinone.
Wherein x and y are hydrogen or a primary, secondary or tertiary amine or a primary, secondary or tertiary aminomethyl, a polyether or polyetherhydroxymethyl wherein y is hydrogen or a primary, secondary or tertiary amine or tertiary aminomethyl or polyether or polyetherhydroxymethyl; with the proviso that either x or y, but not both, is hydrogen.
A number of preferred compounds are those such as the following:
2-[Methylamino-N-(1′-methylethyl)]-9,10-anthraquinone (DNA2-59-1) or its environmentally acceptable acid addition salt wherein the acid addition salt may be either organic or inorganic in nature. Suitable inorganic acids for salt formation include but are not restricted to: phosphoric acid, hydrochloric acid, sulfuric acid or hydrobromic acid. Suitable organic acids for the formation of salts may include, but are not restricted to; acetic acid, formic acid, succinic acid, citric acid, and fumaric acid.
Wherein R 1 is hydrogen or methyl group, wherein n is 1, 2, 3, 4, 5, or 6, wherein R 2 , R 3 and R 4 are hydrogen, methyl or ethyl group, wherein the compound is a free amine or environmentally acceptable acid amine salt. A particularly preferred compound in this group is 2-[methylamino-N-(1′-methyl-4′-N,N-diethylaminobutyl)]anthraquinone diphosphate (DNA1-19-1).
Wherein R 1 is hydrogen or methyl group, wherein R 2 and R 3 are hydrogen, methyl, ethyl, straight-chain alkyl group having 3 to 8 carbon atoms or cyclic alkyl group having 3 to 6 carbon atoms, wherein the compound is a free amine or environmentally acceptable acid addition salt.
Wherein R 1 is hydrogen or methyl group, wherein R 2 and R 3 are hydrogen, methyl, ethyl, straight-chain alkyl group having 3 to 8 carbon atoms or cyclic alkyl group having 3 to 6 carbon atoms, wherein the compound is a free amine or environmentally acceptable acid addition salt.
Wherein R 1 and R 2 are methyl, ethyl group, straight-chain alkyl group having 3 to 8 carbon atoms or cyclic alkyl group having 3 to 6 carbon atoms, wherein the compound is a free amine or environmentally acceptable acid addition salt.
Wherein R 1 and R 2 are hydrogen, methyl, ethyl, straight-chain alkyl group having 3 to 8 carbon atoms or cyclic alkyl group having 3 to 6 carbon atoms, wherein the compound is a free amine or environmentally acceptable acid addition salt.
Wherein n is 1, 2, 3, 4, 5, 6 or 7, wherein R is hydrogen or methyl group.
Synthesis of Anthraquinone Derivatives
Analogs of modified 9,10-anthraquinone were synthesized in the laboratory. The first analog tested was 2-[methylamino-N-(1′-methyl-4′-N′N′-diethylaminobutyl)]-9,10-anthraquinone diphosphate with a molecular weight of 574 and will be referred to as DNA1-19-1. The second primary analog pursued in this project was 2-[Methylamino-N-(1′-methyl)]-9,10-anthraquinone monophospate with a molecular weight of 377 and will be referred to as DNA2-59-1. Both of these analogs of 9,10-anthraquinone are soluble in water. Dozens of other analogs of the modified 9,10-anthraquinone were tested in the laboratory, but DNA1-19-1 and DNA2-59-1 gave the best results as selective algicides. The method of synthesis for the anthraquinone analogs that were screened is provided below. The following examples are intended to further illustrate the invention and are not intended to limit the scope of the invention which is defined by the claims.
The present invention involves the use of the disclosed 9,10-anthraquinone derivatives to control the growth of blue-green algae (cyanobacteria) in water supplies. Specifically, the claimed invention can be used in catfish rearing facilities to help preclude the formation and adsorption of compounds such as geosmin and 2-methylisoboreanol (MIB) from such cyanobacteria. The compounds exhibit focal functional activity against blue-green algae and appear, at the dosages used, to be non-challenging to green algae and to fish. The compounds appear to have a relatively short half-life on the order of a couple of days or less which makes them not persist in the environment and assists in their suitability for use with food related crops. The present method of controlling blue-green algae in an aqueous medium advantageously comprises adding to such medium in an amount ranging from about 0.038 ppm to about 0.125 ppm of a 9,10-anthraquinone derivative.
The compounds described act as toxins and because of this control is quickly achieved when a certain concentration of active agent is maintained for a standard period of time. The activity ascribed to these compounds is such that complete control can be achieved at concentrations ranging down to 0.100 ppm in water. For most applications where an entire body of water such as a pond is being treated, concentrations ranging from about 0.038 to 0.125 ppm will be quite effective with no harm to either fish or green algae. The preferred concentration range will typically be from about 0.100 to about 0.125 ppm. The lower range of concentrations from about 0.038 ppm to about 0.100 ppm may be used to prevent the growth of blue-green algae, maintain better plankton diversity, and help increase the abundance of preferred types of phytoplankton (e.g., green algae) in aquaculture. The higher concentrations of 0.100 to about 0.125 ppm would be of use to kill the blue-green algae.
Treatment is best accomplished by spraying on the water or by subsurface injection, with the desire for as even a distribution as possible in the area to be treated. Spraying equipment is preferably used with aqueous solutions. The body of water to be treated (e.g., catfish pond) should not be mixed (e.g., by mechanical aerators, etc.) before or during application of the treating solution. In general the treating solution will contain about 0.01 to about 99.00% by weight of active ingredient. Although the product is water soluble at the concentrations used, it may be desirable to add a mixing aid in the original concentrate used to prepare the treating composition. For this purpose a water-soluble alcohol such as isopropyl alcohol may be used. A dispersant in the formulation will normally represent from about 15% to about 30% the weight of the composition.
As indicated, the active agents described above are effective in accord with this invention for the selective control of blue-green algae in aquatic systems. It is particularly important that blue-green algae can be controlled with a readily biodegradable active agent. In addition to treating lakes and pond, the invention is useful for the treatment and control of blue-green algae in various aqueous systems.
EXAMPLE 1
Synthesis of 2-methylamino-analogs of 9,10-anthraquinone
General Procedure
2-chloromethylanthraquinone or 2-bromomethylanthraquinone was heated for 15-40 minutes at 80° C. with excess amine in the presence or absence of dimethyl sulfoxide co-solvent. The reaction mixture was cooled and mixed with ice-cold dilute hydrochloric acid and extracted with an organic solvent such as diethyl ether, ethyl acetate or methylene chloride. The aqueous layer was then basified with 20% sodium hydroxide solution and extracted with an organic solvent such as diethyl ether, ethyl acetate or methylene chloride. This extract was washed with water, dried over anhydrous sodium sulfate and evaporated. The product obtained was dissolved in methanol and precipitated as phosphate salt by treating with phosphoric acid. The precipitate was filtered off.
Specific Description
Preparation of 2-[methylamino-N-(1′-methylethyl)]-9,10-anthraquinone monophosphate (DNA2-59-1) (1)
A mixture of 2-chloromethylanthraquinone (10 gm), isopropylamine (15 ml) and dimethyl sulfoxide (15 ml) was heated for 30 minutes at 80° C. The reaction mixture was poured into ice-cold 5% HCl solution (500 ml) and extracted three times with methylene chloride (200 ml). The aqueous layer was basified (pH 12) with sodium hydroxide solution (10%) and extracted three times with diethyl ether. The combined ether layer was washed with water, dried over sodium sulfate and evaporated to give 2-[methylamino-N-(1′-methylethyl)]-9,10-anthraquinone. The purity and identity of the material was assessed by high resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR).
HRMS: 280.1316 (M+H + , C 18 H 18 NO 2 , Cald. 280.1337)
NMR: δ(CDCl 3 , 300 MHz) 1.05 (6H, d, J=6.2 Hz, CH( CH 3 ) 2 ), 2.80 (1H, septet, J=6.2 Hz, CH (CH 3 ) 2 ), 3.84 (2H, s, 2-CH 2 ), 7.65-7.68 (3H, m, 3,6,7-H), 8.07-8.15 (4H, m, 1,4,5,8-H)
This product was dissolved in methanol (500 ml) and treated with methanolic phosphoric acid (10 ml of 85% of H 3 PO 4 in 90 ml of methanol) under stirring and left overnight at room temperature and filtered to give 2-[methylamino-N-(1′-methylethyl)]-9,10-anthraquinone monophosphate (10.5 gm).
Anal. C, 57.59; H, 5.48; N, 3.94; P, 8.07% calcd for C 18 H 17 NO 2 .H 3 PO 4 C, 57.30; H, 5.34; N, 3.71; P, 8.21%.
Chemicals reactants were modified but the same protocol was followed to produce compounds 2 through 11.
2-[Methylamino-N-(methyl)]-9,10-anthraquinone monophosphate (DNA3-19-1) (2)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and methylamine (2M, in dry tetrahydrofuran) in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 252.0997 (M+H + , C 16 H 13 NO 2 , Cald. 252.1024)
NMR: δ(CDCl 3 , 300 MHz) 2.48 (3H, s, CH 3 ), 3.92 (2H, s, 2-CH 2 ), 7.76-7.80 (3H, m, 3,6,7-H), 8.22-8.29 (4H, m, 1,4,5,8-H)
Anal. C, 55.36; H, 5.67; N, 3.94; P, 9.08% calcd for C 16 H 17 NO 2 .H 3 PO 4 C, 55.02; H, 4.62; N, 4.01; P, 8.87%
2-[Methylamino-N-(ethyl)]-9,10-anthraquinone monophosphate (DNA3-17-1) (3)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and ethylamine (2M, in dry tetrahydrofuran) in the presence of dimethyl sulfoxide co-solvent
HRMS: m/e 266.1153 (M+H + , C 17 H 16 NO 2 , Cald. 266.1181)
NMR: δ(CDCl 3 , 300 MHz) 1.12 (3H, t, J=7.1 Hz, CH 2 CH 3 ), 2.26 (2H, q, J=7.1 Hz, CH 2 CH 3 ), 3.90 (2H, s, 2-CH 2 ), 7.70-7.73 (3H, m, 3,6,7-H), 8.13-8.22 (4H, m, 1,4,5,8-H)
Anal. C, 56.49; H, 5.22; N, 3.89; P, 8.24% calcd for C 17 H 15 NO 2 .H 3 PO 4 C, 56.20; H, 4.99; N, 3.86; P, 8.53%
2-[Methylamino-N-(propyl)]-9,10-anthraquinone monophosphate (DNA3-31-1) (4)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and propyl amine in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 280.1321 (M+H + , C 18 H 18 NO 2 , Cald. 280.1259)
NMR: δ(CDCl 3 , 300 MHz) 0.93 (3H, t, J=7.0 Hz, NHCH 2 CH 2 CH 3 ), 1.56 (2H, hextet, J=6.9 Hz, NHCH 2 CH 2 CH 3 ), 2.62 (2H, t, J=6.9 Hz, NH CH 2 CH 2 CH 3 ), 3.95 (2H, s, 2-CH 2 ), 7.77-7.79 (3H, m, 3,6,7-H), 8.22-8.30 (4H, m, 1,4,5,8-H)
Anal. C, 57.19; H, 5.45; N, 3.82; P, 7.98% calcd for C 18 H 17 NO 2 .H 3 PO 4 C, 57.30; H, 5.36; N, 3.71; P, 8.21%
2-[Methylamino-N-(1′1′-dimethylethyl)]-9,10-anthraquinone monophosphate (DNA3-33-1) (5)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and tertiarybutylamine in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 294.1483 (M+H + , C 19 H 20 NO 2 , Cald. 294.1494)
NMR: δ(CDCl 3 , 300 MHz) 1.19 (9H, s, C(CH 3 ) 3 ) 3.90 (2H, s, 2-CH 2 ), 7.77-7.82 (3H, m, 3,6,7-H), 8.23-8.31 (4H, m, 1,4,5,8-H)
Anal. C, 58.11; H, 5.83; N, 3.52; P, 7.69% calcd for C 19 H 19 NO 2 .H 3 PO 4 C, 58.31; H, 5.67; N, 3.58; P, 7.91%
2-[Methylamino-N-(cyclopropyl)]-9,10-anthraquinone monophosphate (DNA3-35-1) (6)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and cyclopropylamine in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 278.1155 (M+H + , C 18 H 16 NO 2 , Cald. 278.1181)
NMR: δ(CDCl 3 , 300 MHz) 0.43 (4H, m, — CH 2 — CH 2 —), 2.17 (1H, m, CHNH), 4.01 (2H, s, 2-CH 2 ), 7.75-7.81 (3H, m, 3,6,7-H), 8.23-8.32 (4H, m, 1,4,5,8-H)
Anal. C, 57.74; H, 5.09; N, 3.51; P, 8.21% calcd for C 18 H 15 NO 2 .H 3 PO 4 C, 57.60; H, 4.83; N, 3.73; P, 8.25%
2-[Methylamino-N-(pentyl)]-9,10-anthraquinone monophosphate (DNA2-55-1) (7)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and pentylamine in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 308.1619 (M+H + , C 20 H 22 NO 2 , Cald. 308.1645)
NMR: δ(CDCl 3 , 300 MHz) 0.78 (3H, t, J=6.7 Hz, 5′-CH 3 ), 1.19 (4H, m, 3′ and 4′-CH 2 ), 1.44 (2H, m, 2′-CH 2 ), 2.53 (2H, t, J=7.4 Hz, 1′-CH 2 ), 3.82 (2H, s, 2-CH 2 ), 7.63-7.68 (3H, m, 3,6,7-H), 8.06-8.14 (4H, m, 1,4,5,8-H)
Anal. C, 59.53; H, 6.25; N, 3.66; P, 7.46% calcd for C 20 H 21 NO 2 .H 3 PO 4 C, 59.26; H, 5.97; N, 3.46; P, 7.64%
2-[Methylamino-N-(1′-methylbutyl)]-9,10-anthraquinone monophosphate (DNA2-53-1) (8)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and 1-methylbutylamine in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 308.1619 (M+H + , C 20 H 22 NO 2 , Cald. 308.1645)
NMR: δ(CDCl 3 , 300 MHz) 0.89 (3H, t, J=7.1 Hz, NHCH(CH 3 )CH 2 CH 2 CH 3 ) 1.08 (3H, d, J=6.2 Hz, NHCH( CH 3 )CH 2 CH 2 CH 3 ), 1.33 (2H, m, NHCH(CH 3 )CH 2 CH 2 CH 3 ), 1.46 (2H, m, NHCH(CH 3 ) CH 2 CH 2 CH 3 ), 2.68 (1H, J=6 Hz, NH CH (CH 3 )CH 2 CH 2 CH 3 ), 3.89, 3.97 (2H, 2×AB doublets, J=14.2 Hz, 2-CH 2 ), 7.74-7.77 (3H, m, 3,6,7-H), 8.20-8.28 (4H, m, 1,4,5,8-H)
Anal. C, 59.11; H, 5.86; N, 3.37; P, 7.51% calcd for C 20 H 21 NO 2 .H 3 PO 4 C, 59.26; H, 5.97; N, 3.46; P, 7.64%
2-[Methylamino-N,N-(di-1′-methylethyl)]-9,10-anthraquinone monophosphate (DNA2-49-1) (9)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and diisopropylamine in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 322.1767 (M+H + , C 21 H 24 NO 2 , Cald. 322.1802)
NMR: δ(CDCl 3 , 300 MHz) 1.03 (12H, d, J=6.5 Hz, N—CH( CH 3 ) 2 ) 3.03 (2H, septet, J=6.5 Hz, N— CH (CH 3 ) 2 ), 3.78 (2H, s, 2-CH 2 ), 7.75-7.88 (3H, m, 3,6,7-H), 8.21-8.31 (4H, m, 1,4,5,8-H)
Anal. C, 60.22; H, 6.20; N, 3.39; P, 7.51% calcd for C 21 H 23 NO 2 .H 3 PO 4 C, 60.14; H, 6.25; N, 3.34; P, 7.39%
2-[Methylamino-N,N-(diethyl)]-9,10-anthraquinone monophosphate (DNA2-51-1) (10)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and diethylamine amine in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 294.1473 (M+H + , C 19 H 20 NO 2 , Cald. 294.1488)
NMR: δ(CDCl 3 , 300 MHz) 1.03 (6H, t, J=7.1 Hz, —N(CH 2 CH 3 ) 2 ), 2.52 (4H, t, J=7.1 Hz, —N( CH 2 CH 3 ) 2 ) 3.67 (2H, s, 2-CH 3 ) 7.71-7.80 (3H m, 3,6,7-H), 8.17-8.24 (4H, m, 1,4,5,8-H)
Anal. C, 58.12; H, 5.69; N, 3.71; P, 7.72% calcd for C 19 H 19 NO 2 .H 3 PO 4 C, 58.31; H, 5.67; N, 3.58; P, 7.91%
2-[Methylamino-N,N-(dibutyl)]-9,10-anthraquinone monophosphate (DNA2-57-1) (11)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone, and dibutylamine in the presence of dimethyl sulfoxide co-solvent.
HRMS: m/e 350.2077 (M+H + , C 23 H 27 NO 2 , Cald. 350.2118)
NMR: δ(CDCl 3 , 300 MHz) 0.83 (6H, t, J=7.2 Hz, N—(CH 2 CH 2 CH 2 CH 3 ) 2 ) 1.27 (4H, m, N—(CH 2 CH 2 CH 2 CH 3 ) 2 ), 1.43 (4H, m, N—(CH 2 CH 2 CH 2 CH 3 ) 2 ), 2.41 (4H, t, J=7.4 Hz, N—( CH 2 CH 2 CH 2 CH 2 CH 3 ) 2 ), 3.65 (2H, s, 2-CH 2 ), 7.69-7.72 (3H, m, 3,6,7-H), 8.15-8.22 (4H, m, 1,4,5,8-H)
Anal. C, 59.29; H, 6.57; N, 3.33; P, 7.11% calcd for C 23 H 27 NO 2 .H 3 PO 4 C, 61.74; H, 6.76; N, 3.13; P, 6.92%
EXAMPLE 2
Preparation of 2-[methylamino-N-(1′-methyl-4′-N,N-diethylaminobutyl)]-9,10-anthraquinone diphosphate (DNA1-19-1) (12)
A mixture of 2-(chloromethyl)anthraquinone (20 g) and 2-amino-5-diethylaminopentane (50 ml) was stirred under nitrogen atmosphere at 80° C. for 40 minutes. The reaction mixture was poured into ice-cold HCl (5%, 500 ml) and extracted with ether (3×150 ml). The ether layer was discarded and the aqueous layer was basified with cold aqueous NaOH (10%) to pH 12 and extracted ether (3×300 ml). The ether extract was washed with water (3×300 ml) dried over anhydrous NaSO4 and evaporated to dryness under vacuum. The crystalline residue obtained was dissolved in methanol (700 ml) and mixed with phosphoric acid (85%, 25 ml in 75 ml of methanol) with efficient mixing. The mixture was allowed to stand for 1 hour, filtered, washed with methanol (4×50 ml) and dried to give 2-[methylamino-N-(1′-methyl-4′-N,N-diethylaminobutyl)]-9,10-anthraquinone diphosphate as a pale yellow amorphous powder (32.8 gm).
HRMS: m/e 379.2399 (M+H + , C 24 H 31 N 2 O 2 , Cald. 379.2385)
NMR: δ(CDCl 3 , 300 MHz) 0.87 (6H, t, J=7.2 Hz, CH 2 CH 3 ), 0.99 (3H, d, J=6.2 Hz, CH 3 —CHCH 2 CH 2 CH 2 N) 1.21 (2H, m, CH 3 —CHCH 2 CH 2 CH 2 N) 1.38 (2H, m, 2H, CH 3 —CH CH 2 CH 2 CH 2 N) 2.27 (2H, dd, J=6.0, 8.9, CH 3 —CHCH 2 CH 2 CH 2 N), 2.38 (4H, q, J=7.2 Hz, —CH 2 CH 3 ), 2.58 (1H, m, CH 3 — CH CH 2 CH 2 CH 2 N), 3.75 and 3.82 (1H each, d, J=14.2 Hz, 2-CH2), 7.60 (3H, m, 3,6,7-H) 8.22-8.29 (4H, m, 1,4,5,8-H)
Anal. C, 50.22; H, 6.20; N, 4.79; P, 10.71% calcd for C 24 H 30 N 2 O 2 .2H 3 PO 4 C, 50.18; H, 6.32; N, 4.88; P, 10.78%
2-[Methylamino-N-(propyl-3′-N,N-diethylaminopropyl)]-9,10-anthraquinone diphosphate (DNA2-25-1) (13)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone and 3-diethylaminopropylamine as reagents and the same protocol which was used in the preparation of compound 12.
HRMS: m/e 351.2038 (M+H + , C 22 H 27 N 2 O 2 , Cald. 351.2067)
NMR: δ(CDCl 3 , 300 MHz) 0.88 (6H, t, J=7.2, N(CH 2 CH 3 ) 2 ), 1.57 (2H, m, NCH 2 CH 2 CH 2 N), 2.37 (4H, t, J=7.1, N( CH 2 CH 3 ) 2 ), 2.42 (2H, t, J=7.2 Hz, NCH 2 CH 2 CH 2 N), 2.57 (2H, t, J=6.7 Hz, N CH 2 CH 2 CH 2 N), 3.79 (2H, s, 2-CH 2 ), 7.61 (3H, m, 3,6,7-H), 8.02-8.11 (4H, m, 1,4,5,8-H)
Anal. C, 48.22; H, 5.84; N, 4.97; P, 11.45% calcd for C 22 H 26 N 2 O 2 .2H 3 PO 4 C, 48.36; H, 5.90; N, 5.13; P, 11.34%
2-[Methylamino-N-(propyl-3′-N,N-dimethylamino)]-9,10-anthraquinone diphosphate (DNA2-23-1) (14)
This compound was prepared by the general procedure using reagents 2-chloromethylanthraquinone and 3-dimethylaminopropylamine as reagents and the same protocol which was used in the preparation of compound 12.
HRMS: m/e 323.1727 (M+H + , C 20 H 22 N 2 O 2 , Cald. 323.1738)
NMR: δ(CDCl 3 , 300 MHz) 1.68 (2H, quintet, J=6.9 Hz, NHCH 2 CH 2 CH 2 N 2 ), 2.20 (6H, s, N(CH 3 ) 2 ), 2.31 (2H, t, J=7.0 Hz, NHCH 2 CH 2 CH 2 N), 2.67 (2H, t, J=6.9 Hz, NH CH 2 CH 2 CH 2 N), 3.93 (2H, s, 2-CH 2 ), 7.74-7.77 (3H, m, 3,6,7-H), 8.19-8.27 (4H, m, 1,4,5,8-H)
Anal. C, 46.61; H, 5.30; N, 5.27; P, 11.78% calcd for C 20 H 22 N 2 O 2 .2H 3 PO 4 C, 46.34; H, 5.44; N, 5.40; P, 11.95%
EXAMPLE 3
Synthesis of 2-ethyl-1′-amino-9,10-anthraquinone analogs
General Procedure
2(1′-Bromoethyl)anthraquinone was heated for 30-60 minutes at 80° C. with excess amine in the presence or absence of dimethyl sulfoxide co-solvent. The reaction mixture was cooled mixed with ice-cold dilute hydrochloric acid and extracted with an organic solvent such as such as diethyl ether, ethyl acetate or methylene chloride. The aqueous layer was then basified with 20% sodium hydroxide solution and extracted with an organic solvent such as diethyl ether, ethyl acetate or methylene chloride. This extract was washed with water, dried over anhydrous sodium sulfate and evaporated.
The product obtained was dissolved in methanol and precipitated as phosphate salt by treating with phosphoric acid. The precipitate was filtered off.
2-[1′-Amino-N-(1′-methylethyl)ethyl]-9,10-anthraquinone 9,10-anthraquinone (DNA2-89-1) (15)
Specific Description
2[1′-Bromoethyl]anthraquinone (2 gm) was refluxed for 1 hour with isopropylamine (5 ml) and dimethyl sulfoxide (5 ml). The reaction mixture was cooled mixed with ice-cold dilute hydrochloric acid (5%, 400 ml) and extracted three times with ether (100 ml). The aqueous layer was then basified (pH 12) with 20% sodium hydroxide solution and extracted three times with ether. The combined ether extract was washed with water, dried over anhydrous sodium sulfate and evaporated to give 2-[1′-amino-N-(1″-methylethyl)ethyl]-9,10-anthraquinone.
HRMS: 294.1512 (M+H + , C 19 H 20 NO 2 , Cald. 294.1494)
NMR: δ(CDCl 3 , 300 MHz) 0.97, 1.02 (6H, 2×d, J=6.3 Hz, NHCH( CH 3 ) 2 ), 1.36 (3H, d, J=6.6 Hz, —CH(NH) CH 3 ), 2.60 (1H, septet, J=6.2 Hz, NH CH (CH 3 ) 2 ), 4.06 (1H, q, J=6.6 Hz, CH (NH)CH 3 ), 7.72-7.78 (3H, m, 3,6,7-H), 8.19-8.28 (4H, m, 1,4,5,8-H)
Anal. C, 58.11; H, 5.76; N, 3.37; P, 7.71% calcd for C 19 H 19 N 2 O 2 .H 3 PO 4 C, 58.31; H, 5.67; N, 3.58; P, 7.91%
The product obtained was dissolved in methanol and precipitated as phosphate salt by treating with phosphoric acid. The precipitate was filtered off.
EXAMPLE 4
2-[1′-Amino-N-(propyl-3″-N,N-diethylamino)ethyl]-9,10-anthraquinone (DNA2-87-1) (16)
This compound was prepared by the general procedure using reagents 2-[1′-bromoethyl]anthraquinone and 3-diethylaminopropylamine as reagents and the general protocol described above in synthesis of 2-ethyl-1′-amino-9,10-anthraquinone analogs.
HRMS: 364.2168 (M+H + , C 23 H 28 N 2 O 2 , Cald. 364.2151)
NMR: δ(CDCl 3 , 300 MHz) 0.94 (6H, t, J=7.1 Hz, NHCH 2 CH 2 CH 2 N (CH 2 CH 3 ) 2 ), 1.35 (3H, d, J=6.6 Hz, 2-CHNH CH 3 ) 1.58 (2H, quintet, J=6.9 Hz, NHCH 2 CH 2 CH 2 N), 2.34-2.56 (8H, m, NH CH 2 CH 2 CH 2 N( CH 2 CH 3 ) 2 ), 3.89 (1H, q, J=6.5 Hz, CH NHCH 3 ), 7.71-7.77 (3H, m, 3,6,7,-H), 8.17-8.24 (4H, m, 1,4,5,8-H)
Anal. C, 49.16; H, 4.87; N, 4.87; P, 11.36% calcd for C 23 H 28 N 2 O 2 .2H 3 PO 4 C, 49.29; H, 6.11; N, 5.00; P, 11.05%
EXAMPLE 5
Synthesis of 1-methylamino-analogs of 9,10-anthraquinone
General Procedure
1-chloromethylanthraquinone or 1-bromomethylanthraquinone was heated for 15-60 minutes at 80° C. with excess amine in the presence or absence of dimethyl sulfoxide co-solvent. The reaction mixture was cooled mixed with ice-cold dilute hydrochloric acid and extracted with an organic solvent such as such as diethyl ether, ethyl acetate or methylene chloride. The aqueous layer then basified with 20% sodium hydroxide solution and extracted with an organic solvent such as diethyl ether, ethyl actetat or methylene chloride. This extract was washed with water, dried over anhdrous sodium sulfate and evaporated. The product obtained was dissolved in methanol and precipitated as phosphate salt by treating with phosphoric acid. The precipitate was filtered off.
Specific Description
1-[Methylamino-N,N-(diethyl)]-9,10-anthraquinone monophosphate (DNA4-39-1) (17)
1-Bromomethylanthraquinone (500 mg) was refluxed for 1 hour with diethylamine (10 ml). Excess diethylamine was removed under vacuum and the products were mixed with ice-cold dilute hydrochloric acid (5%, 200 ml) and extracted with methylene chloride. The aqueous layer was then basified (pH 12) with 20% sodium hydroxide solution and extracted three times with methylene chloride. This extract was washed with water, dried over anhydrous sodium sulfate and evaporated. The product obtained was crystallized from methylene chloride crystalline compound.
MW; m/e 294.1462 (M+H + , C 19 H 20 NO 2 , Cald. 294.1488)
NMR: δ(CDCl 3 , 300 MHz) 1.08 (6H, t, J=7.0 Hz, N(CH 2 CH 3 ) 2 ), 2.61 (4H, q, J=7.0 Hz, N( CH 2 CH 3 ) 2 ), 4.23 (2H, s, 1-CH 2 ), 7.72-7.76 (4H, m, 2,3,6,7-H), 8.25-8.38 (3H, m, 4,5,8-H)
The product obtained was dissolved in methanol and precipitated as phosphate salt by treating with phosphoric acid. The precipitate was filtered off.
Anal. C, 58.54; H, 5.82; N, 3.60; P, 7.76% calcd for C 19 H 19 NO 2 .H 3 PO 4 C, 58.31; H, 5.67; N, 3.58; P, 7.91%
Example 6
Synthesis of 1-amino- analogs of 9,10-anthraquinone
General Procedure
1-Chloroanthraquinone or 1-bromoanthraquinone was heated for 1-2 hours at 100° C. with excess amine in the presence or absence of dimethyl sulfoxide co-solvent. The reaction mixture was cooled and mixed with ice-cold dilute hydrochloric acid and extracted with an organic solvent such as such as diethyl ether, ethyl acetate or methylene chloride. The aqueous layer was then basified with 20% sodium hydroxide solution and extracted with an organic solvent such as diethyl ether, ethyl acetate or methylene chloride. This extract was washed with water, dried over anhydrous sodium sulfate and evaporated. The product obtained was dissolved in methanol and crystallized as phosphate salt by treating with phosphoric acid. The crystalline product was filtered off.
Specific Description
Synthesis of 1-amino-N-(propyl-3′-N,N-diethylamino)-9,10-anthraquinone phosphate (DNA2-91-1) (18)
A mixture of 1-chloroanthraquinone (2 gm) and 3-diethylamino-1-propylamine (10 ml) was heated for 2 hours at 100° C., poured into ice-cold HCl solution (5%, 200 ml) and extracted three times with ether. The aqueous layer was basified (pH 12) with sodium hydroxide solution (10%) and extracted three times with ether. The ether layer was washed with water dried over anhydrous sodium sulfate and evaporated to dryness to give 1-amino-N-(propyl-3′-N,N-diethylamino)-9,10-anthraquinone as a red gum.
HRMS: 336.1872 (M+H + , C 21 H 24 N 2 O 2 , Cald. 336.1838)
NMR: δ(CDCl 3 , 300 MHz) 0.96 (6H, t, J=7.1 Hz, NCH 2 CH 3 ), 1.57 (2H, quintet, J=6.9 Hz, NHCH 2 CH 2 CH 2 N) 2.47 (6H, q, J=7.1 Hz, NHCH 2 CH 2 CH 2 N( CH 2 CH 3 ) 2 ), 3.17 (2H, q, J=6.7 Hz, NH CH 2 CH 2 CH 2 N(CH 2 CH 3 ) 2 ), 6.84 (1H, d, J=8.2 Hz, 2-H), 7.31 (1H, t, J=8.2 Hz, 3-H), 7.37 (1H, d, J=8.1 Hz, 4-H), 7.57 (2H, m, 6, 7-H), 8.07 (2H, m, 5, 8-H), 9.55 (1H, t, NH)
This gum was dissolved in methanol (200 ml) and treated with phosphoric acid (85%, 3 ml) to give 1-(amino-N-propyl-3-N,N-diethylamino)anthraquinone phosphate as a red crystalline compound (1.6 gm).
Anal. C, 57.11; H, 6.45; N, 6.41; P, 7.07% calcd for C 21 H 24 N 2 O 2 .H 3 PO 4 C, 58.06; H, 6.26; N, 6.45; P, 7.13%
Synthesis of 1-amino-N-(propyl-3′-N,N-dimethylamino)-9,10-anthraquinone phosphate (DNA2-93-1) (19)
This compound was prepared using 1-chloroanthraquinone and 3-dimethylaminopropylamine as reagents and the same protocol which was used in the preparation of compound 18.
HRMS: 308.1541 (M+H + , C 19 H 20 N 2 O 2 , Cald. 308.1525)
NMR: δ(CDCl 3 , 300 MHz) 1.80 (2H, quintet, J=7 Hz, NHCH 2 CH 2 CH 2 N(CH 3 ) 2 ), 2.20 (6H, s, N( CH 3 ) 2 ), 2.35 (2H, t, J=7.0 Hz, NHCH 2 CH 2 CH 2 N (CH 3 ) 2 ), 3.22 (2H, q, J=6.8 Hz, NH CH 2 CH 2 CH 2 N (CH 3 ) 2 ), 6.89 (1H, d, J=8.2 Hz, 2-H), 7.35 (1H, t, J=8.1 Hz, 3-H), 7.41 (1H, d, J=6.6 Hz, 4-H), 7.60 (2H, m, 6, 7-H), 8.10 (1H, m, 5, 8-H), 9.58 (1H, t, NH)
Anal. C, 55.98; H, 5.84; N, 6.77; P, 7.48% calcd for C 19 H 20 N 2 O 2 .H 3 PO 4 C, 56.16; H, 5.70; N, 6.89; P, 7.62%
Example 7
Synthesis of Polyethylene Glycol Derivatives of 1-hydroxy and 2-hydroxy Anthraquinones
General Procedure
A mixture of 1-chloroanthraqinone or 2-chloroanthraqinone and equal amount of potassium carbonate in ethylene glycols was heated at 120-140° C. for 3 hours and poured into cold water. The precipitate formed was filtered off, dried and purified by column chromatography on silica gel using a mixture of chloroform and methanol as the solvent. The product was crystallized from chloroform/ether.
Specific Description
Synthesis of 1-[2-[2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]ethoxy]-9,10-anthraquinone (DNA3-45-1) (20)
A mixture of 1-chloroanthraquinone (4 gm) potassium carbonate, (4 gm) in tetraethyleneglycol (15 ml) was heated for three hours at 120° C., poured into cool water and filtered off. The solid obtained was chromatographed over silica gel and eluted with methylene chloride:methanol (99:1) gave 1-[2-[2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]ethoxy]-9,10-anthraquinone. This compound was crystallized from ether to give a yellow crystalline compound.
HRMS: . . . (M+H + , C 22 H 24 O 7 , Cald. 401.1600)
NMR: δ(CDCl 3 , 300 MHz) 3.23 (1H, t, J=6.0 Hz, —OH), 3.41(2H, m, 8′-CH 2 ), 3.45-3.56 (8H, m, 4′,5′,6′,7′-CH 2 ), 3.68 (2H, m, 3′-CH 2 ), 3.81 (2H, t, J=4.9 Hz, 2′-CH 2 ), 4.08 (2H, t, J=4.9 Hz, 1′-CH 2 ), 7.12 (1H, br d, J=8.4 Hz, 2-H), 7.42 (1H, br t, J=8.1 Hz, 3-H), 7.51 (2H, m, 6,7-H), 7.64 (1H, dd, J=7.7, 0.7 Hz, 4-H), 7.92 (1H, dd, J=7.6, 1.3 Hz, 8-H) 7.96 (1H, dd, J=7.7, 1.2 Hz, 5-H)
Synthesis of 2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]-9,10-anthraquinone (DNA3-9-1) (21)
A mixture of 2-choroanthraquinone (2.5 gm) potassium carbonate (2.5 gm) in triethyleneglycol monomethyl ether (15 ml) was heated for three hours at 140° C., poured into cool water and filtered off. The solid obtained was chromatographed over silica gel and eluted with methylene chloride:methanol (96:4) yielded Synthesis of 2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]-9,10-anthraquinone. This compound was crystallized from ether to give yellow crystalline compounds.
HRMS: . . . (M+H + , C 21 H 22 O 6 , Cald. 371.1495)
NMR: δ(CDCl 3 , 300 MHz) 3.35 (3H, s, —OCH 3 ), 3.53 (2H, m, 6′-CH 2 ), 3.63-3.69 (4H, m, 4′,5′-CH 2 ), 3.75 (2H, m, 3′-CH 2 ), 3.91 (2H, t, J=4.7 Hz, 2′-CH 2 ), 4.30 (2H, t, J=4.4 Hz, 1′-CH 2 ), 7.27 (1H, dd, J=8.7, 2.5 Hz, 3-H), 7.70 (1H, d, J=2.5 Hz, 1-H), 7.75 (2H, m, 6,7-H), 8.22 (1H, d, J=8.8 Hz, 4-H), 8.25 (2H, m, 5,8-H)
Chemicals reactants were modified but the same protocol was followed from compounds 20 and 21 to produce compounds 23 through 33.
1-(2-Methoxyethoxy)-9,10-anthraquinone (DNA3-13-1) (22)
This compound was prepared using 1-chloranthraquinone and ethylene glycol monomethyl ether as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 17 H 14 O 4 , Cald. 283.0970)
NMR: δ(CDCl 3 , 300 MHz) 3.53 (3H, s, —OCH 3 ), 3.91 (2H, t, J=4.9 Hz, 2′-CH 2 ), 4.31 (2H, t, J=4.7 Hz, 1′-CH 2 ), 7.36 (1H, br d, J=8.2 Hz, 2-H), 7.68 (1H, br t, J=8.0 Hz, 3-H), 7.74 (2H, m, 6,7-H), 7.96 (1H, dd, J=7.8, 0.9 Hz, 4-H), 8.21 (1H, dd, J=7.5, 1.5 Hz, 8-H) 8.25 (1H, dd, J=7.3, 1.3 Hz, 5-H)
2-(2-Methoxyethoxy)-9,10-anthraquinone (DNA2-97-1) (23)
This compound was prepared using 2-chloranthraquinone and ethylene glycol monomethyl ether as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 17 H 14 O 4 , Cald. 283.0970)
NMR: δ(CDCl 3 , 300 MHz) 3.47 (3H, s, —OCH 3 ), 3.82 (2H, t, J=4.5 Hz, 2′-CH 2 ), 4.31 (2H, t, J=4.5 Hz, 1′-CH 2 ), 7.31 (1H, dd, J=8.6, 2.5 Hz, 3-H), 7.73 (1H, d, J=2.5 Hz, 1-H), 7.76 (2H, m, 6,7-H), 8.25 (1H, d, J=8.5 Hz, 4-H), 8.28 (2H, m, 5,8-H)
1-[2-(2-Methoxyethoxy)ethoxy]-9,10-anthraquinone (DNA3-7-1) (24)
This compound was prepared using 1-chloranthraquinone and diethylene glycol monomethyl ether as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 19 H 18 O 5 , Cald. 327.1232)
NMR: δ(CDCl 3 , 300 MHz) 3.37 (3H, s, —OCH 3 ), 3.59 (2H, m, 4′-CH 2 ), 3.84 (2H, m, 3′-CH 2 ), 4.02 (2H, t, J=5.0 Hz, 2′-CH 2 ), 4.32 (2H, t, J=4.9 Hz, 1′-CH 2 ), 7.34 (1H, br d, J=8.2 Hz, 2-H), 7.66 (1H, br t, J=7.9 Hz, 3-H), 7.72 (2H, m, 6,7-H), 7.94 (1H, dd, J=7.6, 0.6 Hz, 4-H), 8.20 (1H, dd, J=7.6, 1.4 Hz, 8-H) 8.22 (1H, dd, J=7.6, 1.3 Hz, 5-H)
2-[2-(2-Methoxyethoxy)ethoxy]-9,10-anthraquinone (DNA3-5-1) (25)
This compound was prepared using 2-chloranthraquinone and diethylene glycol monomethyl ether as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 19 H 18 O 5 , Cald. 327.1232)
NMR: δ(CDCl 3 , 300 MHz) 3.37 (3H, s, —OCH 3 ), 3.56 (2H, m, 4′-CH 2 ), 3.72 (2H, m, 3′-CH 2 ), 3.90 (2H, t, J=4.7 Hz, 2′-CH 2 ), 4.30 (2H, t, J=4.6 Hz, 1′-CH 2 ), 7.25 (1H, dd, J=8.6, 2.6 Hz, 3-H), 7.67 (1H, d, J=2.5 Hz, 1-H), 7.73 (2H, m, 6,7-H), 8.19 (1H, d, J=8.8 Hz, 4-H), 8.23 (2H, m, 5,8-H)
1-[2-[2-(2-Hydroxyethoxy)ethoxy]ethoxy]-9,10-anthraquinone (DNA3-15-1) (26)
This compound was prepared using 1-chloranthraquinone and triethylene glycol as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 20 H 20 O 6 , Cald. 357.1338)
NMR: δ(CDCl 3 , 300 MHz) 2.79 (1H, t, J=6.0 Hz, —OH), 3.61 (2H, m, 6-CH 2 ), 3.69-3.72 (8H, m, 4′,5′-CH 2 ), 3.85 (2H, m, 3′-CH 2 ), 4.00 (2H, t, J=4.5 Hz, 2′-CH 2 ), 4.29 (2H, t, J=4.5 Hz, 1′-CH 2 ), 7.31 (1H, br d, J=8.3 Hz, 2-H), 7.63 (1H, br t, J=7.8 Hz, 3-H), 7.70 (2H, m, 6,7-H), 7.91 (1H, brd, J=7.6 Hz, 4-H), 8.17 (1H, dd, J=7.8, 1.3 Hz, 8-H) 8.20 (1H, dd, J=7.4, 1.3 Hz, 5-H)
2-[2-[2-(2-Hydroxyethoxy)ethoxy]ethoxy]-9,10-anthraquinone (DNA2-99-2) (27)
This compound was prepared using 2-chloranthraquinone and triethylene glycol as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 20 H 20 O 6 , Cald. 357.1338)
NMR: δ(CDCl 3 , 300 MHz) 2.50 (1H, t, J=5.7 Hz, —OH), 3.61 (2H, m, 6′-CH 2 ), 3.66-3.77 (4H, m, 3′,4′,5′-CH 2 ), 3.91 (2H, t, J=4.6 Hz, 2′-CH 2 ), 4.30 (2H, t, J=4.6 Hz, 1′-CH 2 ), 7.27 (1H, dd, J=8.7, 2.6 Hz, 3-H), 7.69 (1H, d, J=2.6 Hz, 1-H), 7.74 (2H, m, 6,7-H), 8.20 (1H, d, J=8.7 Hz, 4-H), 8.24 (2H, m, 5,8-H)
1-[2-[2-(2-Methoxyethoxy)ethoxy]ethoxy]-9,10-anthraquinone (DNA3-11-1) (28)
This compound was prepared using 1-chloranthraquinone and triethylene glycol monomethyl ether as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 21 H 22 O 6 , Cald. 371.1495)
NMR: δ(CDCl 3 , 300 MHz) 3.36 (3H, s, —OCH 3 ), 3.54 (2H, m, 4′-CH 2 ), 3.64-3.72 (4H, m, 4′,5′-CH 2 ), 3.86 (2H, m, 3′-CH 2 ), 4.03 (2H, t, J=5.0 Hz, 2′-CH 2 ), 4.34 (2H, t, J=4.9 Hz, 1′-CH 2 ), 7.38 (1H, d, J=8.2 Hz, 2-H), 7.66 (1H, br t, J=8 Hz, 3-H), 7.75 (2H, m, 6,7-H), 7.97 (1H, dd, J=7.5, 0.8 Hz, 4-H), 8.23 (1H, dd, J=7.5, 1.6 Hz, 8-H) 8.22 (1H, dd, J=7.5, 1.5 Hz, 5H)
2-[2-[2-[2-(2-Hydroxyethoxy)ethoxy]ethoxy]ethoxy]-9,10-anthraquinone (DNA3-43-1) (29)
This compound was prepared using 2-chloranthraquinone and tetraethylene glycol as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . . (M+H + , C 22 H 24 O 7 , Cald. 401.1600)
NMR: δ(CDCl 3 , 300 MHz) 3.02 (1H, s, —OH), 3.49 (2H, m, 8′-CH 2 ), 3.66-3.77 (10H, m, 3′,4′,5′,6′,7′-CH 2 ), 3.78 (2H, t, J=4.6 Hz, 2′-CH 2 ), 4.14 (2H, t, J=4.6 Hz, 1′-CH 2 ), 7.07 (1H, dd, J=8.7, 2.6 Hz, 3-H), 7.45 (1H, d, J=2.6 Hz, 1-H), 7.58 (2H, m, 6,7-H), 7.98 (1H, d, J=8.7 Hz, 4-H), 8.03 (2H, m, 5,8-H)
1-[2-[2-[2-(2-Methoxyethoxy)ethoxy]ethoxy]ethoxy]-9,10-anthraquinone (DNA3-53-1) (30)
This compound was prepared using 1-chloranthraquinone and tetraethylene glycol monomethyl ether as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 23 H 26 O 7 , Cald. 415.1757)
NMR: δ(CDCl 3 , 300 MHz) 3.12 (3H, s, —OCH 3 ), 3.29 (2H, m, 8′-CH 2 ), 3.39-3.51 (8H, m, 4′,5′,6′,7′-CH 2 ), 3.65 (2H, m, 3′-CH 2 ), 3.77 (2H, t, J=4.8 Hz, 2′-CH 2 ), 4.04 (2H, t, J=4.8 Hz, 1′-CH 2 ), 7.07 (1H, br d, J=8.3 Hz, 2-H), 7.38 (1H, br t, J=7.9 Hz, 3-H), 7.47 (2H, m, 6,7-H), 7.59 (1H, br d, J=7.5 Hz, 4-H), 7.88 (1H, br d, J=7.6, 1.4 Hz, 8-H) 7.92 (1H, dd, J=7.6, 1.3 Hz, 5H)
2-[2-[2-[2-(2-Methoxyethoxy)ethoxy]ethoxy]ethoxy]-9,10-anthraquinone (DNA3-55-1) (31)
This compound was prepared using 2-chloranthraquinone and tetraethylene glycol monomethyl ether as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 23 H 26 O 7 , Cald. 415.1757)
NMR: δ(CDCl 3 , 300 MHz) 3.21 (3H, s, —OCH 3 ), 3.39 (2H, m, 8′-CH 2 ), 3.46-3.62 (10H, m, 3′,4′,5′,6′,7′-CH 2 ), 3.77 (2H, t, J=4.6 Hz, 2′-CH 2 ), 4.11 (2H, t, J=4.6 Hz, 1′-CH 2 ), 7.04 (1H, dd, J=8.5, 2.6 Hz, 3-H), 7.42 (1H, d, J=2.5 Hz, 1-H), 7.56 (2H, m, 6,7-H), 7.95 (1H, d, J=8.6 Hz, 4-H), 8.01 (2H, m, 5,8-H)
1-[2-[2-[2-[2-(2-Hydroxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]-9,10-anthraquinone (DNA3-49-1) (32)
This compound was prepared using 1-chloranthraquinone and pentaethylene glycol as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 24 H 28 O 8 , Cald. 445.1862)
NMR: δ(CDCl 3 , 300 MHz) 3.44 (2H, m, 10′-CH 2 ), 3.50-3.58 (12H, m, 4′,5′,6′,7′,8′,9′-CH 2 ), 3.73 (2H, m, 3′-CH 2 ), 3.88 (2H, t, J=4.9 Hz, 2′-CH 2 ), 4.16 (2H, t, J=4.7 Hz, 1′-CH 2 ), 7.20 (1H, br d, J=8.4 Hz, 2-H), 7.51 (1H, br t, J=8.0 Hz, 3-H), 7.58 (2H, m, 6,7-H), 7.73 (1H, dd, J=7.7, 0.8 Hz, 4-H), 8.01 (1H, dd, J=7.6, 1.4 Hz, 8-H) 8.04 (1H, dd, J=7.8, 1.5 Hz, 5H)
2-[2-[2-[2-[2-(2-Hydroxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]-9,10-anthraquinone (DNA3-51-1) (33)
This compound was prepared using 2-chloranthraquinone and pentaethylene glycol as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 1-hydroxy and 2-hydroxyanthraquinones.
HRMS: . . . (M+H + , C 24 H 28 O 8 , Cald. 445.1862)
NMR: δ(CDCl 3 , 300 MHz) 3.60 (2H, m, 10′-CH 2 ), 3.64-3.77 (14H, m, 3′,4′,5′,6′,7′,8′,9′-CH 2 ), 3.92 (2H, t, J=4.6 Hz, 2′-CH 2 ), 4.32 (2H, t, J=4.6 Hz, 1′-CH 2 ), 7.30 (1H, dd, J=8.6, 2.7 Hz, 3-H), 7.73 (1H, d, J=2.7 Hz, 1-H), 7.77 (2H, m, 6,7-H), 8.25 (1H, d, J=8.6 Hz, 4-H), 8.29 (2H, m, 5,8-H)
EXAMPLE 8
Synthesis of Polyethylene Glycol Derivatives of 2-(hydroxymethyl)anthraquinones
General Procedure
A mixture of 2-(chloromethyl)anthraqinone and twice the amount of barium hydroxide in poly(eththyleneglycol) was sonicated 10 minutes and then stirred for 3 hours at room temperature. The reaction mixture was poured into cold water and the precipitate formed was filtered off, dried and purified by column chromatography on silica gel using a mixture of hexanes and acetone as the solvent. The product was crystallized from ether/hexanes.
Specific Description
Synthesis of 2-methylene-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]-9,10-anthraquinone (DNA3-61-1) (36)
A mixture of 2-(chloromethyl)anthraqinone (600 mg) and twice the amount of barium hydroxide (1.2 gm) in trimethylene glycol monomethyl ether was sonicated 10 minutes and then stirred for 3 hours at room temperature. The reaction mixture was poured into cold water and the precipitate formed was filtered off. The solid obtained was purified by column chromatography on silica gel using a mixture of hexanes:acetone 3:1 as the solvent. The product was crystallized from ether/hexanes.
HRMS: . . . (M+H + , C 22 H 24 O 6 , Cald. 385.1651)
NMR: δ(CDCl 3 , 300 MHz) 3.27 (3H, s, —OCH 3 ), 3.46 (2H, m, 6′-CH 2 ), 3.56-3.64 (10H, m, 1′,2′,3′,4′,5′-CH 2 ), 4.62 (2H, s, 2-CH 2 ), 7.64-7.70 (3H, m, 3,6,7-H), 8.07-8.14 (4H, m, 1,4,5,8-H)
2-Methylene-[2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]-9,10-anthraquinone (DNA3-57-1) (34)
This compound was prepared using 2-chlormethylanthraquinone and triethylene glycol as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 2-(hydroxymethyl) anthraquinones.
HRMS: . . . (M+H + , C 21 H 22 O 6 , Cald. 371.1416)
NMR: δ(CDCl 3 , 300 MHz) 3.59 (2H, m, 6′-CH 2 ), 3.60-3.71 (10H, m, 1′, 2′,3′,4′,5′-CH 2 ), 4.67 (2H, s, 2-CH 2 ), 7.65-7.75 (3H, m, 3,6,7-H), 8.17-8.22 (4H, m, 1,4,5,8-H)
2-Methylene-[2-[2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]ethoxy]-9,10-anthraquinone (DNA3-59-1) (35)
This compound was prepared using 2-chlormethylanthraquinone and tetraethylene glycol as reagents and the general procedure which was described above to prepare polyethylene glycol derivatives of 2-(hydroxymethyl)anthraquinones.
HRMS: . . . (M+H + , C 23 H 26 O 7 , Cald. 415.1757)
NMR: δ(CDCl 3 , 300 MHz) 3.60 (2H, m, 6′-CH 2 ), 3.67-3.72 (14H, m, 1′,2,′,3′,4′,5′,6′,7′-CH 2 ), 4.73 (2H, s, 2-CH 2 ), 7.75-7.85 (3H, m, 3,6,7-H), 8.24-8.32 (4H, m, 1,4,5,8-H)
Laboratory Tests
Laboratory Screening of Anthraquinone Derivatives
The anthraquinone derivatives were screened for selective toxicity towards Oscillatoria perornata , previously isolated from a Mississippi catfish pond, using the method of Schrader et al. (1997). The green alga Selenastrum capricornutum (obtained from the United States Environmental Protection Agency, Corvallis, Oreg.) was used as the representative green algal species in the bioassay since it is a common species found in southeastern United States catfish ponds. Absorbance readings were graphed, and graphs were used to determine the LOEC (lowest-observed-effect concentration) and the LCIC (lowest-complete-inhibition concentration) for each anthraquinone analog. In addition, a 96-hour 50% inhibition concentration (IC50) was determined for DNA1-19-1 and DNA2-59-1 by using the method described by Schrader et al. (1998b). Stock solutions of DNA1-19-1 and DNA2-59-1 were prepared so that final concentrations screened for 96-hour IC50 determinations were as follows: 1) 0, 0.01, 0.033, 0.1, 0.333, 1.0, 3.3, and 10.0 μM DNA1-19-1 for both O. perornata and S. capricornutum; 2) 0, 0.003, 0.01, 0.033, 0.1, 0.333, 1.0, and 3.333 μM DNA2-59-1 for O. perornata ; and 3) 0, 0.1, 0.333, 1.0, 3.333, 10.0, 33.333, and 100.0 μM DNA2-59-1 for S. capricornutum . Estimation of the IC50 was determined by plotting 96-hour absorbance readings against logarithmic dilution values of the anthraquinone analogs. The screening results of the anthraquinone derivatives and commercially available analogs of anthraquinone are presented in Tables 1 and 2, respectively. Results of the IC50 determinations are presented in Table 3. The results in Table 1 reveal that DNA1-19-1 and DNA2-59-1 are the most promising analogs since these two compounds had the lowest LOEC and LCIC values for O. perornata (10 nM and 100 nM, respectively). Based upon IC50 results in Table 3, DNA2-59-1 appears to be more toxic and selective towards O. perornata than DNA1-19-1. Both DNA1-19-1 and DNA2-59-1 are very selectively toxic towards O. perornata compared to S. capricornutum.
The method described by Schrader et al. (2000) was used to determine the potential for using the anthraquinone derivatives as selective algicides in catfish aquaculture ponds. All catfish ponds used in efficacy tests were maintained using commercial pond management practices and were located at the Thad Cochran Pond Facility, Mississippi State University, Stoneville, Miss. Anthraquinone analogs were dissolved in deionized water before application to water within the limnocorrals.
Limnocorrals in which test compound was applied to the enclosed water were randomly selected, and control (no test compound applied) limnocorrals were included in each efficacy study. For each sampling, two water samples (250 mL) were obtained from within each limnocorral (approximately 6-8 cm below the water surface and from opposite sides of each limnocorral) and mixed together in a 500 mL sample bottle to provide a representative sample of the water contained within the limnocorral.
EXAMPLE 9
Efficacy Testing of DNA1-19-1
Three pond efficacy studies were conducted with DNA1-19-1. In the first study, six limnocorrals (open-ended fiberglass cylinders, 2.44 m in diameter and 1.53 m high; Solar Components Corporation, Manchester, N.H.) were placed in a 4-ha earthen catfish pond. The pond was chosen due to the presence of a bloom of O. perornata . The water within each limnocorral received mixing in the same manner as used by Schrader et al. (2000). Three randomly selected limnocorrals were used as treatments (received DNA1-19-1), and the other three limnocorrals were controls. Water samples were taken before application of DNA1-19-1 (2 μM or 1,148 μg/L/enclosure), 16 hours after application, and at days 3, 8, and 10. Water samples were analyzed for chlorophyll a by the chloroform-methanol extraction method followed by spectroscopy (S. W. Lloyd and C. S. Tucker, Comparison of three solvent systems for extraction of chlorophyll a from fish pond phytoplankton communities, J. World Aquacult. Soc. (1988), vol. 19, pp. 36-40), phytoplankton community structure and enumeration (American Public Health Association, American Water-Works Association, and Water Pollution Control Federation, Standard Methods for the Examination of Water and Wastewater, 18 th Edition. APHA, Washington, D.C. (1992)), and for geosmin and MIB levels using solid phase microextraction with gas chromatography-mass spectrometry (SPME-GC-MS) (Lloyd et al., J. M. Lea, P. V. Zimba and C. C. Grimm, Rapid analysis of geosmin and 2-methylisoborneol in water using solid-phase microextraction procedures. Water Res. (1998), vol. 32, pp. 2140-2146). To perform phytoplankton identification and enumeration, water samples were processed by preserving 50-mL subsamples with Lugol's solution and storing them at 4° C. until they could be identified and counted as “natural units” (i.e., colonies, filaments, or unialgal cells) using a Sedgewick-Rafter counting chamber at 300× magnification. Eukaryotic algae were identified to the genus level and filamentous cyanobacteria to the species.
EXAMPLE 10
In the second study with DNA1-19-1, twelve limnocorrals that were the same size as those used in the first study were placed in another 4-ha earthen catfish pond. The pond also had a bloom of O. perornata . Randomly selected limnocorrals were used as follows: 1) three controls; 2) three received DNA1-19-1 at an application rate of 1 μM (574 μg/L) per enclosure; 3) three received DNA1-19-1 at an application rate of 0.3 μM (191 mg/L) per enclosure; and 4) three received DNA1-19-1 at an application rate of 0.1 μM (57.4 μg/L) per enclosure. The sampling regime and procedures used in the first study were followed in a similar manner, except that water samples were obtained before DNA1-19-1 application, 16 hours after application, and at days 2, 4, and 7.
Example 11
The third study with DNA1-19-1 essentially duplicated the second study (Example 10) in time. The same pond containing a bloom of O. perornata , the same procedures, and the same conditions used in the second study were used again.
Results of Examples 9-11
Chlorophyll a levels decreased significantly within 24 hours with an application rate of 2 μM of DNA1-19-1 to pond water contained within the limnocorrals (see data of Table 1).
TABLE 1
First efficacy study of the effect of DNA1-19-1 on chlorophyll a
levels in pond water. Each point is the mean ± standard
deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Chlorophyll a
Chlorophyll a
Levels (mg/L) in
Levels (mg/L) in
Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
370.3 a ± 16.8
365.7 a ± 16.9
0.7
441.8 a ± 12.0
160.2 b ± 5.3
3.0
416.2 a ± 75.5
237.6 b ± 25.2
8.0
248.2 a ± 144.4
526.2 a ± 157.3
10.0
139.0 a ± 77.4
368.7 b ± 94.9
Numbers of filaments of O. perornata were significantly reduced by application of 2 μM DNA1-19-1, but numbers then began to increase within 3 days (see data of Table 2).
TABLE 2
First efficacy study of the effect of DNA1-19-1 on the abundance
of Oscillatoria perornata in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three
replicate limnocorrals. Means on the same day with the same
letter are not significantly different (P < 0.05) based upon LSD
values.
Filaments/mL in
Filaments/mL in
Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
3,547 a ± 49.9
4,556 a ± 519.8
0.7
4,383 a ± 472.0
980 b ± 115.3
3.0
5,997 a ± 550.1
1,961 b ± 708.6
8.0
5,709 a ± 915.4
3,172 a ± 1,592.9
10.0
4,267 a ± 1,363.4
3,575 a ± 1798.8
Levels of MIB were also significantly reduced from 15,250 ng/mL (ppb) to near 970 ng/mL and remained much lower than MIB levels in the controls for 8 days (see data of Table 3).
TABLE 3
First efficacy study of the effect of DNA1-19-1 on 2-
methylisoborneol levels in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
MIB a Levels
MIB a Levels (mg/L)
(mg/L)
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
14.73 a ± 1.86
15.25 a ± 3.43
0.7
20.16 a ± 2.55
0.97 b ± 0.19
3.0
40.75 a ± 7.80
4.56 b ± 1.87
8.0
4.01 a ± 4.01
0.55 a ± 0.33
10.0
9.03 a ± 3.78
5.46 a ± 5.26
MIB a = 2-methylisoborneol
Numbers of green algae (Division Chlorophyta) in controls and in limnocorrals treated with 2 μM DNA1-19-1 were not significantly different based upon Least Significant Difference (LSD) values until 10 days after application of DNA1-19-1 (see data of Table 4).
TABLE 4
First efficacy study of the effect of DNA1-19-1 on the abundance
of green algae in pond water. Each point is the mean ± standard
deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Natural Units/mL
Natural Units/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
1,298 a ± 264
2,047 a ± 126
0.7
750 a ± 115
1,845 a ± 251
3.0
692 a ± 264
346 a ± 173
8.0
577 a ± 231
115 a ± 115
10.0
577 a ± 153
0 b ± 0
The most common genera of green algae observed in pond water samples obtained during the three efficacy studies of DNA1-19-1 were Actinastrum, Ankistrodesmus, Closterium, Coelastrum, Crucigenia, Oocystis, Pediastrum, Scenedesmus, Schroederia , and Staurastrum.
Results of the second and third efficacy study of DNA1-19-1 revealed a lack of reduction of chlorophyll a levels, numbers of O. perornata filaments, and 2-methylisoborneol levels compared to controls at application rates of 1, 0.3, and 0.1 μM. Therefore, DNA1-19-1 is effective in selectively reducing numbers of O. perornata and MIB levels in pond water when applied at 2 μM, but not at application rates of 1 μM, 0.3 μM, or 0.1 μM.
Efficacy Testing of DNA2-59-1
Three efficacy tests were performed using DNA2-59-1. The following examples indicate various aspects of DNA2-59-1 according to the invention.
EXAMPLE 12
In the first study, application rates of 0.1 μM (37.7 μg/L), 0.3 μM (125 μg/L), and 1.0 μM (377 μg/L) of DNA2-59-1 were tested using limnocorrals (three replicates per concentration) that were of the same type used for testing DNA1-19-1. Three limnocorrals were used as controls. These limnocorrals were set up in a 3.3-ha earthen pond that had O. perornata and Anabaena circinalis (geosmin producer) present. Water within each limnocorral was not mixed by aeration (using airstones; see Schrader et al., 2000) until the day after the limnocorrals were placed in the pond. This delay in mixing was to permit suspended sediment and organic matter to settle to the pond bottom. The chemical nature of DNA2-59-1 is such that it has less of a positive charge than DNA1-19-1, and, therefore, DNA2-59-1 is less likely than DNA1-19-1 to bind to suspended sediment and organic matter, subsequently permitting a greater availability of DNA2-59-1 in the water column for uptake by phytoplankton. Approximately 30 minutes after mixing the water within each limnocorral, randomly selected treatment limnocorrals received the appropriate amounts of DNA2-59-1. Water samples were collected before application of the test compound, 20 minutes after application (for anthraquinone level determination by HPLC), and 24 hours after application. This study proceeded for only one day since a thunderstorm disrupted the circular shape and integrity of the limnocorrals; however, due to the rapid toxicity of DNA2-59-1 towards O. perornata , positive results were observed 24 hours after the initial treatment and a determination of dose-response results was made. The same tests and analytical procedures performed on water samples taken during the efficacy testing of DNA1-19-1 were used in the three efficacy tests undertaken with DNA2-59-1. Water samples were also analyzed to determine the persistence of DNA2-59-1 in the pond water, and this analysis was performed by using high-pressure liquid chromatography (HPLC) (method and results are described later).
Chlorophyll a levels were significantly reduced by application of DNA2-59-1 at 1 and 0.3 μM, but not at 0.1 μM compared to the controls (see data of Table 5).
TABLE 5
First efficacy study of the effect of DNA2-59-1 on chlorophyll a
levels in pond water. Each point is the mean ± standard
deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Chlorophyll
Chlorophyll
Chlorophyll a
Chlorophyll
a (mg/L) in
a (mg/L) in
(mg/L) in
a (mg/L) in
Treatment
Treatment
Treatment
Time
Control
(37.7 ppb)
(125.7 ppb)
(377 ppb)
(day)
Limnocorrals
Limnocorrals
Limnocorrals
Limnocorrals
0
102.5 a ± 2.5
97.2 a ± 1.2
99.9 a ± 1.6
95.5 a ± 3.2
0.7
111.3 a ± 4.2
98.6 a ± 2.7
54.1 b ± 0.8
46.2 c ± 0.8
Application rates of 0.1, 0.3 and 1 μM DNA2-59-1 significantly reduced numbers of O. perornata filaments compared to controls (see data of Table 6).
TABLE 6
First efficacy study of the effect of DNA2-59-1 on the abundance
of Oscillatoria perornata in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three
replicate limnocorrals. Means on the same day with the same
letter are not significantly different (P < 0.05) based upon LSD
values.
Filaments/mL
Filaments/mL
Filaments/mL
Filaments/mL
in Treatment
in Treatment
in Treatment
Time
in Control
(37.7 ppb)
(125.7 ppb)
(377 ppb)
(day)
Limnocorrals
Limnocorrals
Limnocorrals
Limnocorrals
0
2,595 a ± 300
2,941 a ± 173
3,056 a ± 416
2,076 a ± 100
0.7
3,056 a ± 58
2,076 b ± 300
1,442 b ± 404
1,326 b ± 58
Levels of MIB decreased in all of the treatments and controls, but to a greater degree and significantly more in limnocorrals receiving applications of 0.3 and 1 μM DNA2-59-1 compared to the controls and limnocorrals receiving applications of 0.1 μM DNA2-59-1 (see data of Table 7).
TABLE 7
First efficacy study of the effect of DNA2-59-1 on 2-
methylisoborneol levels in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
MIB Levels
MIB Levels
MIB Levels
(ng/L) in
(ng/L) in
MIB Levels (ng/L) in
(ng/L) in
Treatment
Treatment
Treatment
Time
Control
(37.7 ppb)
(125.7 ppb)
(377 ppb)
(day)
Limnocorrals
Limnocorrals
Limnocorrals
Limnocorrals
0
2,422 a ± 238
2,249 a ± 39
2,581 a ± 133
2,470 a ± 146
0.7
1,568 a ± 385
1,402 a ± 113
535 b ± 58
892 c ± 128
Geosmin levels also decreased in all of the treatments and controls, but to a greater degree and significantly more in limnocorrals receiving 1 μM DNA2-59-1 compared to the controls and limnocorrals receiving applications of 0.1 and 0.3 μM DNA2-59-1 (see data of Table 8).
TABLE 8
First efficacy study of the effect of DNA2-59-1 on geosmin levels
in pond water. Each point is the mean ± standard deviation of
the mean of measurements in three replicate limnocorrals. Means
on the same day with the same letter are not significantly
different (P < 0.05) based upon LSD values.
Geosmin
Geosmin
Levels
Levels
Geosmin
Geosmin Levels
(ng/L) in
(ng/L) in
Levels (ng/L) in
(ng/L) in
Treatment
Treatment
Treatment
Time
Control
(37.7 ppb)
(125.7 ppb)
(377 ppb)
(day)
Limnocorrals
Limnocorrals
Limnocorrals
Limnocorrals
0
258 a ± 53
208 a ± 47
317 a ± 5
286 a ± 41
0.7
80 a ± 9
101 b ± 23
77 a ± 8
44 c ± 7
Numbers of Anabaena circinalis were significantly reduced in limnocorrals receiving 1 μM DNA2-59-1 compared to the controls and limnocorrals receiving applications of 0.1 and 0.3 μM DNA2-59-1 (see data of Table 9).
TABLE 9
First efficacy study of the effect of DNA2-59-1 on the abundance
of Anabaena circinalis in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Filaments/mL
Filaments/mL
Filaments/mL
Filaments/mL
in Treatment
in Treatment
in Treatment
Time
in Control
(37.7 ppb)
(125.7 ppb)
(377 ppb)
(day)
Limnocorrals
Limnocorrals
Limnocorrals
Limnocorrals
0
980 a ± 264
807 a ± 200
1,211 a ± 173
1,384 a ± 624
0.7
1,038 a ± 346
865 a ± 519
634 a ± 360
0 b ± 0
In fact, in water samples from limnocorrals receiving 1 μM DNA2-59-1, no filaments of A. circinalis were observed to be present 16 hours after application of 1 μM DNA2-59-1. This first efficacy study was the only one of the three conducted with applications of DNA2-59-1 in which geosmin was determined to be present in the pond water. Numbers of green algae were not significantly affected by applications of DNA2-59-1 at 0.1, 0.3 and 1 μM compared to the controls (see data of Table 10).
TABLE 10
First efficacy study of the effect of DNA2-59-1 on the abundance
of green algae in pond water. Each point is the mean ± standard
deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Natural
Natural
Natural
Units/mL in
Units/mL in
Natural Units/mL in
Units/mL in
Treatment
Treatment
Treatment
Time
Control
(37.7 ppb)
(125.7 ppb)
(377 ppb)
(day)
Limnocorrals
Limnocorrals
Limnocorrals
Limnocorrals
0
1,326 a ± 264
1,442 a ± 264
1,326 a ± 953
923 a ± 360
0.7
1,788 a ± 360
2,018 a ± 200
1,384 a ± 300
1,269 a ± 818
The most common genera of green algae observed in pond water samples taken during the three efficacy tests of DNA2-59-1 were Actinastrum, Ankistrodesmus, Closterium, Coelastrum, Crucigenia, Kirchneriella, Dictyosphaerium, Oocystis, Pediastrum, Scenedesmus, Schroederia, Snowella , and Staurastrum.
EXAMPLE 13
In the second efficacy test with DNA2-59-1, six limnocorrals (1.53 m in diameter and 1.53 m high) were placed in a 0.1-ha earthen pond containing a heavy bloom of O. perornata . The same delay in mixing the water within the limnocorrals used in the first efficacy study was utilized. Water within three randomly selected limnocorrals received an application rate of 0.3 μM DNA2-59-1, and the other three limnocorrals were controls. Water samples were collected before application of DNA2-59-1, 20 minutes after application, and at days 1, 2, 3, and 7. The same tests and methods used in the first efficacy testing of DNA2-59-1 were used.
Chlorophyll a levels were significantly lower in pond water within limnocorrals receiving application of 0.3 μM DNA2-59-1 for three days after application (see data of Table 11).
TABLE 11
Second efficacy study of the effect of DNA2-59-1 on chlorophyll
a levels in pond water. Each point is the mean ± standard
deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Chlorophyll a
Chlorophyll a
Levels (mg/L) in
Levels (mg/L) in
Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
549.1 a ± 29.1
538.6 a ± 19.1
1
798.2 a ± 52.7
588.7 b ± 20.2
2
932.8 a ± 55.1
638.9 b ± 21.2
3
1,013.8 a ± 40.1
733.0 b ± 36.8
7
896.7 a ± 61.7
709.3 a ± 37.8
Numbers of O. perornata and Raphidiopsis brookii were significantly and dramatically reduced within three days of application of 0.3 μM DNA2-59-1 (see data of Tables 12 and 13, respectively).
TABLE 12
Second efficacy study of the effect of DNA2-59-1 on the abundance
of Oscillatoria perornata in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three
replicate limnocorrals. Means on the same day with the same
letter are not significantly different (P < 0.05) based upon LSD
values.
Filaments/mL
Filaments/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
2,480 a ± 321
2,480 a ± 634
1
2,595 a ± 173
1,615 a ± 404
2
2,653 a ± 321
1,442 a ± 351
3
3,345 a ± 416
923 b ± 208
7
2,999 a ± 610
1,096 a ± 416
TABLE 13
Second efficacy study of the effect of DNA2-59-1 on the abundance
of Raphidiopsis brookii in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Filaments/mL
Filaments/mL in
in Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
7,093 a ± 173
7,036 a ± 896
1
6,920 a ± 793
3,748 b ± 378
2
7,324 a ± 642
750 b ± 305
3
7,555 a ± 611
58 b ± 58
7
8,420 a ± 2,192
231 b ± 58
Levels of MIB were significantly reduced after three days application of 0.3 μM DNA2-59-1 (see data of Table 14).
TABLE 14
Second efficacy study of the effect of DNA2-59-1 on 2-
methylisoborneol levels in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
MIB Levels (ng/L)
MIB Levels (ng/L)
in
in
Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
751 a ± 33.1
574 a ± 55.3
1
723 a ± 156.5
330 a ± 59.8
2
1,092 a ± 348.3
243 a ± 97.7
3
1,437 a ± 509.2
216 b ± 89.9
7
644 a ± 25.5
412 a ± 204.6
Numbers of Oscillatoria geminata were also reduced by application of 0.3 μM DNA2-59-1, though not significantly (see data of Table 15).
TABLE 15
Second efficacy study of the effect of DNA2-59-1 on the abundance
of Oscillatoria geminata in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Filaments/mL
Filaments/mL in
in Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
692 a ± 346
519 a ± 100
1
577 a ± 153
231 a ± 231
2
577 a ± 321
115 a ± 58
3
231 a ± 115
173 a ± 173
7
115 a ± 115
115 a ± 115
Numbers of Oscillatoria agardhii were not affected by application of 0.3 μM DNA2-59-1 (see data of Table 16).
TABLE 16
Second efficacy study of the effect of DNA2-59-1 on the abundance
of Oscillatoria agardhii in pond water. Each point is the mean ±
standard deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Filaments/mL
Filaments/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
17,878 a ± 1,020
15,398 a ± 699
1
21,569 a ± 2,598
19,146 a ± 838
2
25,144 a ± 873
23,298 a ± 472
3
28,432 a ± 416
27,624 a ± 1,912
7
23,991 a ± 4,574
28,893 a ± 2,473
Neither O. geminata nor O. agardhii have been linked to off-flavor compound production. Green algae and diatoms (division Chromophyta, class Bacillariophyceae) were not significantly affected by applications of 0.3 μM DNA2-59-1 (see data of Tables 17 and 18, respectively).
TABLE 17
Second efficacy study of the effect of DNA2-59-1 on the abundance
of green algae in pond water. Each point is the mean ± standard
deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Natural Units/mL
Natural Units/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
11,187 a ± 665
11,649 a ± 1,096
1
14,878 a ± 780
11,764 a ± 1,057
2
16,781 a ± 1,995
12,514 a ± 1,000
3
13,321 a ± 1,644
8,881 a ± 1,068
7
13,436 a ± 1,906
10,322 a ± 208
TABLE 18
Second efficacy study of the effect of DNA2-59-1 on the abundance
of diatoms in pond water. Each point is the mean ± standard
deviation of the mean of measurements in three replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Natural Units/mL
Natural Units/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
6,805 a ± 1,496
6,055 a ± 499
1
7,381 a ± 807
6,401 a ± 300
2
5,248 a ± 153
5,075 a ± 305
3
4,959 a ± 665
4,902 a ± 602
7
2,652 a ± 321
3,575 a ± 305
EXAMPLE 14
For the third efficacy test with DNA2-59-1, twelve limnocorrals (2.44 m in diameter and 1.53 m high) were placed in a 4-ha earthen pond containing a bloom of O. perornata . The same procedures, application rate (0.3 μM), and methods used in the second efficacy test of DNA2-59-1 were used except six limnocorrals were randomly selected to receive an application rate of 0.3 μM DNA2-59-1 while the other six limnocorrals were controls. Water samples were collected before application of DNA2-59-1, 20 minutes after application, and at days 1, 2, 3, 4, and 7. The same tests and methods used in the first efficacy testing of DNA2-59-1 were used.
Chlorophyll a levels in the pond water within treatment limnocorrals were significantly reduced 24 hours after application of 0.3 μM DNA2-59-1 (see data of Table 19).
TABLE 19
Third efficacy study of the effect of DNA2-59-1 on chlorophyll a
levels in pond water. Each point is the mean ± standard mean of
measurements in six replicate limnocorrals. Means on the same
day with the same letter are not significantly different (P < 0.05)
based upon LSD values.
Chlorophyll a
Chlorophyll a
Levels (mg/L) in
Levels (mg/L) in
Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
549.1 a ± 7.9
556.6 a ± 4.9
1
617.8 a ± 5.7
219.6 b ± 14.6
2
646.8 a ± 10.9
72.6 b ± 0.9
3
697.4 a ± 5.5
191.0 b ± 6.4
4
768.7 a ± 11.1
631.8 b ± 52.3
7
946.0 a ± 20.9
942.0 a ± 54.1
Numbers of O. perornata were significantly reduced within 24 hours after application of 0.3 μM DNA2-59-1 (see data of Table 20).
TABLE 20
Third efficacy study of the effect of DNA2-59-1 on the abundance
of Oscillatoria perornata in pond water. Each point is the mean ±
standard deviation of the mean of measurements in six replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Filaments/mL in
Filaments/mL in
Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
1,355 a ± 113
1,845 a ± 193
1
2,249 a ± 357
58 b ± 58
2
2,652 a ± 305
346 b ± 63
3
2,018 a ± 288
461 b ± 198
4
3,460 a ± 473
317 b ± 83
7
1,499 a ± 406
461 b ± 115
Levels of 2-methylisoborneol were significantly reduced 24 hours after application of 0.3 μM DNA2-59-1 (see data of Table 21).
TABLE 21
Third efficacy study of the effect of DNA2-59-1 on 2-
methylisoborneol levels in pond water. Each point is the mean ±
standard deviation of the mean of measurements in six replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
MIB Levels (ng/L)
MIB Levels (ng/L)
in
in
Control
Treatment
Time (days)
Limnocorrals
Limnocorrals
0
1,525 a ± 99
1,515 a ± 83
1
1,192 a ± 69
677 b ± 57
2
1,318 a ± 96
93 b ± 24
3
1,784 a ± 285
163 b ± 42
4
2,123 a ± 112
483 b ± 100
7
693 a ± 99
653 a ± 170
Numbers of Raphidiopsis brookii and Cylindrospermopsis spp. were significantly reduced one day after application of 0.3 μM DNA2-59-1 (see data of Tables 22 and 23, respectively).
TABLE 22
Third efficacy study of the effect of DNA2-59-1 on the abundance
of Raphidiopsis brookii in pond water. Each point is the mean ±
standard deviation of the mean of measurements in six replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Filaments/mL
Filaments/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
122,116 a ± 5,426
11,903 a ± 6,295
1
107,180 a ± 5,738
6,286 b ± 935
2
11,113 a ± 3,676
807 b ± 139
3
119,896 a ± 3,852
1,038 b ± 260
4
118,743 a ± 6,115
692 b ± 257
7
139,908 a ± 7,661
10,495 b ± 7,909
TABLE 23
Third efficacy study of the effect of DNA2-59-1 on the abundance
of Cylindrospermopsis spp. in pond water. Each point is the mean ±
standard deviation of the mean of measurements in six replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Filaments/mL
Filaments/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
27,451 a ± 5,063
30,795 a ± 5,158
1
35,755 a ± 4,387
7,526 b ± 799
2
52,427 a ± 3,788
231 b ± 106
3
47,809 a ± 4,217
404 b ± 73
4
66,321 a ± 11,420
317 b ± 83
7
59,804 a ± 6,629
565 b ± 243
The abundance of Oscillatoria geminate in pond water within limnocorrals receiving 0.3 μM DNA2-59-1 remained lower than in the control limnocorrals for four days after application and were significantly lower than controls from two days through four days after application (see data of Table 24).
TABLE 24
Third efficacy study of the effect of DNA2-59-1 on the abundance
of Oscillatoria geminata in pond water. Each point is the mean ±
standard deviation of the mean of measurements in six replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Filaments/mL
Filaments/mL
Time
in Control
in Treatment
(days)
Limnocorrals
Limnocorrals
0
2,912 a ± 375
2,018 a ± 478
1
1,038 a ± 334
490 a ± 192
2
2,941 a ± 788
404 b ± 106
3
3,345 a ± 746
692 b ± 219
4
5,248 a ± 1,183
1,644 b ± 282
7
2,191 a ± 1,139
6,921 b ± 1,431
Numbers of Oscillatoria agardhii were significantly reduced by application of 0.3 μM DNA2-59-1 while Microcystis spp. were not greatly affected in pond water within limnocorrals receiving 0.3 μM DNA2-59-1 compared to the control limnocorrals (see data of Tables 25 and 26, respectively).
TABLE 25
Third efficacy study of the effect of DNA2-59-1 on the abundance
of Oscillatoria agardhii in pond water. Each point is the mean ±
standard deviation of the mean of measurements in six replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values 25 and
26, respectively).
Filaments/mL
Filaments/mL
Time
in Control
in Treatment
(days)
Limnocorrals
Limnocorrals
0
4,239 a ± 309
3,258 a ± 1,772
1
5,421 a ± 432
2,797 b ± 1,297
2
7,497 a ± 343
2,768 b ± 638
3
8,362 a ± 689
2,249 b ± 1,345
4
8,103 a ± 1,123
3,575 b ± 1,197
7
11,534 a ± 914
7,036 b ± 2,276
TABLE 26
Third efficacy study of the effect of DNA2-59-1 on the abundance
of Microcystis spp. in pond water. Each point is the mean ±
standard deviation of the mean of measurements in six replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Natural Units/mL
Natural Units/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
2,393 a ± 353
2,393 a ± 851
1
2,844a ± 346
2,018 a ± 1,265
2
2,047 a ± 401
1,528 a ± 552
3
2,480 a ± 339
2,537 a ± 1,361
4
2,595 a ± 511
3,056 a ± 1,098
7
2,134 a ± 288
3,349 a ± 1,743
Numbers of green algae and diatoms began to increase dramatically in treatment limnocorrals three days after application of 0.3 μM DNA2-59-1 and were significantly higher than numbers in the pond water within the control limnocorrals (see data of Tables 27 and 28, respectively).
TABLE 27
Third efficacy study of the effect of DNA2-59-1 on the abundance
of green algae in pond water. Each point is the mean ±
standard deviation of the mean of measurements in six replicate
limnocorrals. Means on the same day with the same letter are not
significantly different (P < 0.05) based upon LSD values.
Natural Units/mL
Natural Units/mL
in Control
in Treatment
Time (days)
Limnocorrals
Limnocorrals
0
1,499 a ± 251
2,105 a ± 230
1
1,187 a ± 303
1,211 a ± 260
2
1,672 a ± 302
1,874 a ± 333
3
1,442 a ± 351
6,199 b ± 564
4
2,307 a ± 548
10,606 b ± 1,803
7
2,708 a ± 460
4,902 b ± 577
TABLE 28 Third efficacy study of the effect of DNA2-59-1 on the abundance of diatoms in pond water. Each point is the mean ± standard deviation of the mean of measurements in six replicate limnocorrals. Means on the same day with the same letter are not significantly different (P < 0.05) based upon LSD values. Natural Units/mL Natural Units/mL in Control in Treatment Time (days) Limnocorrals Limnocorrals 0 779 a ± 203 1,009 a ± 130 1 1,730 a ± 382 1,672 a ± 115 2 1,096 a ± 188 4,527 b ± 450 3 1,096 a ± 243 19,637 b ± 1,032 4 1,499 a ± 231 61,649 b ± 6,393 7 1,961 a ± 263 43,829 b ± 2,575
HPLC Determination of Anthraquinone Derivatives Level in Water Sample
Approximately 15 mL each of water samples from DNA2-59-1 efficacy testing that were designated for HPLC analysis were placed in scintillation vials and held in a freezer. Water samples were later melted at room temperature, and 5 mL of each sample was then filtered through a nylon membrane filter (13 mm diameter and 0.45 μm; Whatman International, Maidstone, England) using a 5 mL syringe (Hamilton Company, Reno, Nev.) and a 13 mm syringe filter holder (Fisher Scientific Company, Pittsburgh, Pa.). Filtrate (1 mL) was placed in 2 mL vials and capped using teflon/rubber septum caps (National Scientific Company, Jeddah, Saudia Arabia). The filter paper was removed and placed in a scintillation vial to which 2 mL of HPLC grade methanol (Fisher Scientific, Fair Lawn, N.J.) was added and then sonicated for 5 minutes. The methanol solution was then filtered using a nylon membrane acrodisc (25 mm and 0.45 μm; Pall Life Sciences, Ann Arbor, Mich.), and the methanol filtrate was placed in separate 2 mL vials.
Filtrate samples were analyzed using a Waters 2690 Alliance HPLC containing a 996 PDA detector and a XTerra RP 18 column (150 mm×4.6 mm, 5 μm particle size; Waters Corporation, Milford, Mass.). The mobile phase consisted of 25 mM sodium dihydrogenphosphate in 0.1% phosphoric acid (A) and acetonitrile (B). The gradient was from 80A/20B in 15 minutes to 40A/60B. After each run, a 5 minute wash with methanol was performed, followed by equilibrating the column for 10 minutes with 80A/20B. The temperature was set at 40° C., the flow rate was 1 mL/minute, the detection wavelength 256 nm, and the sample injection volume was 10 μL. All solvents used were HPLC grade (Fisher Scientific, Fair Lawn, N.J.).
Means and standard deviations of data were determined and graphed. The graphs were used to help determine the half-life of DNA2-59-1 in the pond water. Because of the short duration of the first efficacy study, the half-life of DNA2-59-1 in the pond water could not be determined. Results from the second and third efficacy study indicate a half-life of 19 hours for DNA2-59-1 in the pond water (see data of Tables 29 and 30, respectively).
TABLE 29
Second efficacy study of DNA2-59-1 with determination of
dissipation rate and half-life in pond water. Each point is the
mean ± standard deviation of the mean of
measurements in six replicate limnocorrals.
DNA2-59-1
Levels (mg/L)
Time (hours)
in Pond Water
0
94.8 ± 11.5
24
36.1 ± 4.5
48
16.3 ± 0.4
72
7.6 ± 0.7
168
0.0 ± 0.0
TABLE 30
Third efficacy study of DNA2-59-1 with determination of
dissipation rate and half-life in pond water. Each point is the
mean ± standard deviation of the mean of
measurements in six replicate limnocorrals.
DNA2-59-1
Levels (mg/L)
Time (hours)
in Pond Water
0
90.6 ± 7.9
24
31.5 ± 4.4
48
9.2 ± 3.2
72
2.2 ± 0.5
96
0.0 ± 0.0
The attempts to develop a reproducible analytical method to determine the levels of DNA1-19-1 in the pond water were unsuccessful. DNA1-19-1 is believed to bind quickly to suspended soil particles due to the positively charged nature of the 2-methylamino chain; evident by the lack of detection of DNA1-19-1 in the water. Since the levels of suspended soil particles in each water sample varied and an accurate measurement of the soil particles present in each sample could not be obtained, the consistent recoveries of DNA1-19-1 from the particulate portions of water samples could not be achieved. DNA1-19-1 could not be detected in soluble fractions of water samples collected at and after 24 hours after application of DNA1-19-1 to water within limnocorrals.
Laboratory Tests
Laboratory Screening of Anthraquinone Derivatives
The anthraquinone derivatives were screened for selective toxicity towards Oscillatoria perornata , previously isolated from a Mississippi catfish pond, using the method of Schrader et al. (A rapid bioassay for selective algicides. Weed Technol. (1997), vol. 11, pp. 767-774). The green alga Selenastrum capricornutum (obtained from the United States Environmental Protection Agency, Corvallis, Oreg.) was used as the representative green algal species in the bioassay since it is a common species found in southeastern United States catfish ponds. Absorbance readings were graphed, and graphs were used to determine the LOEC (lowest-observed-effect concentration) and the LCIC (lowest-complete-inhibition concentration) for each anthraquinone analog. In addition, a 96-hour 50% inhibition concentration (IC50) was determined for DNA1-19-1 and DNA2-59-1 by using the method described by Schrader et al. (K. K. Schradar, M. Q. de Regt, P. D. Tidwell, C. S. Tucker and S. O. Duke, Selective growth inhibition of the musty-odor producing cyanobacterium Oscillatoria cf. chalybea by natural compounds. Bull. Environ. Contam. Toxicol. (1998a), vol.60, pp. 651-658). Stock solutions of DNA1-19-1 and DNA2-59-1 were prepared so that final concentrations screened for 96-hour IC50 determinations were as follows: 1) 0, 0.01, 0.033, 0.1, 0.333, 1.0, 3.3, and 10.0 μM DNA1-19-1 for both O. perornata and S. capricornutum; 2) 0, 0.003, 0.01, 0.033, 0.1, 0.333, 1.0, and 3.333 μM DNA2-59-1 for O. perornata ; and 3) 0, 0.1, 0.333, 1.0, 3.333, 10.0, 33.333, and 100.0 μM DNA2-59-1 for S. capricornutum . Estimation of the IC50 was determined by plotting 96-hour absorbance readings against logarithmic dilution values of the anthraquinone analogs. The screening results of the anthraquinone derivatives and commercially available analogs of anthraquinone are presented in Tables 31 and 32, respectively. Results of the IC50 determinations are presented in Table 33. The results in Table 31 reveal that DNA1-19-1 and DNA2-59-1 are the most promising analogs since these two compounds had the lowest LOEC and LCIC values for O. perornata (10 nM and 100 nM, respectively). Based upon IC50 results in Table 33, DNA2-59-1 appears to be more toxic and selective towards O. perornata than DNA1-19-1. Both DNA1-19-1 and DNA2-59-1 are very selectively toxic towards O. perornata compared to S. capricornutum .
TABLE 31
Rapid Screening Results of Modified 9, 10-Anthraquinone Analogs
Test Organism
Test
Oscillatoria perornata
Selenastrum capricornutum
Compound
LOEC a (nM)
LCIC b (nM)
LOEC a (nM)
LCIC b (nM)
DNA1-19-1
10
100
10,000
10,000
DNA2-23-1
100
1,000
10,000
10,000
DNA2-25-1
100
100
10,000
10,000
DNA2-49-1
1,000
1,000
100,000
1 × 10 6
DNA2-51-1
100
100
10,000
100,000
DNA2-53-1
100
100
100,000
100,000
DNA2-55-1
1,000
1,000
100,000
100,000
DNA2-57-1
1,000
1,000
100,000
1 × 10 6
DNA2-59-1
10
100
10,000
100,000
DNA2-87-1
1,000
100,000
100,000
100,000
DNA2-89-1
1,000
1,000
100,000
100,000
DNA2-91-1
10,000
10,000
100,000
100,000
DNA2-93-1
1,000
1,000
100,000
100,000
DNA2-97-2
10,000
10,000
>100,000
>100,000
DNA2-99-2
10,000
10,000
>100,000
>100,000
DNA3-5-1
100
10,000
>100,000
>100,000
DNA3-7-1
10,000
100,000
>100,000
>100,000
DNA3-9-1
10,000
10,000
>100,000
>100,000
DNA3-11-1
10,000
10,000
>100,000
>100,000
DNA3-13-1
10,000
10,000
10
>100,000
DNA3-15-1
10,000
10,000
10
>100,000
DNA3-17-1
1,000
1,000
10,000
10,000
DNA3-19-1
1,000
1,000
10,000
10,000
DNA3-31-1
1,000
1,000
10,000
10,000
DNA3-33-1
1,000
1,000
1,000
10,000
DNA3-35-1
1,000
1,000
10,000
100,000
DNA3-49-1
1,000
10,000
>100,000
>100,000
DNA3-51-1
100
100,000
>100,000
>100,000
DNA3-53-1
10,000
100,000
100,000
>100,000
DNA3-55-1
10,000
100,000
>100,000
>100,000
DNA3-57-1
100
10,000
>100,000
>100,000
DNA3-59-1
100
100,000
>100,000
>100,000
DNA3-61-1
100
10,000
>100,000
>100,000
DNA4-39-1
100
1,000
10,000
10,000
a LOEC = Lowest-observed-effect concentration; the concentration that inhibited growth but did not actually completely kill the test organism.
b LCIC = Lowest-complete-inhibition concentration; the concentration that completely killed the test organism.
nM = nanomolar concentration
In addition to the novel anthraquinone analogs screened, several commercially available anthraquinone analogs (Sigma-Aldrich, St. Louis, Mo.) were screened to determine their toxicity towards O. perornata (Table 32).
TABLE 32
Rapid Screening Results of Commercially-available Analogs of
9, 10-Anthraquinone
Oscillatoria
Selenastrum
perornata
capricornutum
Test Compound
LCIC a (nM)
LCIC a (nM)
1-aminoanthraquinone
100,000
>100,000
2-aminoanthraquinone
>100,000
>100,000
1-(methylamino) anthraquinone
100,000
>100,000
anthraquinone-1,5-disulfonic acid
>1,000,000
>1,000,000
anthraquinone-2-carboxylic acid
>1,000,000
>1,000,000
2-hydroxymethyl-anthraquinone
10,000
100,000
1,4-dihydroxyanthraquinone
>100,000
>100,000
1,8-dihydroxyanthraquinone
100,000
>100,000
LCIC a = Lowest-complete-inhibition concentration; the concentration that completely killed the test organism.
nM = nanomolar
TABLE 33
IC50 a Determination of DNA1-19-1 and DNA2-59-1
Test Organism
Oscillatoria
Selanastrum
perornata
capricornutum
Test Compound
IC50 a (nM)
IC50 a (nM)
DNA1-19-1
63
5,012
DNA2-59-1
6.3
5,623
a IC50 = 96-hour 50% inhibition concentration.
nM = nanomolar concentration | We have now discovered that certain 9,10-anthraquinone derivatives we developed possess potent activity against O. perornata while possessing a sufficiently high level of solubility in water to make their activity against O. perornata viable. These compounds possess a high level of activity against O. perornata yet are relatively non-toxic to green algae and fishes. The compounds also possess a relatively short half-life. The compounds represent a new means to providing compounds possessing a high degree of selective activity against blue-green algae while being physiologically tolerated by catfish and green algae. The compounds provide a means for controlling blue-green algae in managed bodies of water that are destined for public use or consumption. | 2 |
This invention relates to fused silica optical elements and in particular to methods for extending the useful life of such elements in ultraviolet optical systems.
BACKGROUND OF THE INVENTION
Only two materials, CaF 2 and fused silica, are currently available for refractive optical components such as lenses for ultraviolet optical systems operating in the wavelength range of about 193 nm which is the nominal wavelength of the ArF excimer laser. CaF is a crystal and is much more difficult to form into optical components than fused silica which has an amorphous molecular structure.
A serious problem associated with fused silica is that various types of radiation including UV radiation will cause it to undergo "densification" or "compaction". This is a serious problem for the makers of stepper and scanner equipment which uses ArF lasers as a light source for integrated circuit lithography. These machines use very high precision lenses to condition the laser beam for printing circuits on silicon wafers. Compaction in the range of a few parts per million for imaging of a photo mask can seriously degrade performance of these lenses.
The densification of fused silica with radiation has been studied thoroughly. See for example N. F. Borrelli, et al., "Densification of fused silica under 193-nm excitation", J. Opt. Soc. Am. B/Vol. 14, No. 7/July 1997 and the many papers cited therein. That study found "that the derived densification follows a universal function of the dose, defined as the product of the number [N] of pulses and the square of the fluence [I] per pulse". FIG. 14 of that report has been reproduced here as FIG. 1. This and other prior art reports suggest methods of reducing the rate of densification such as by decreasing the energy per pulse and increasing the number of pulses.
What is needed is a better method of preparing fused silica to extend the useful life of fused silica optical elements used with high energy ultraviolet light sources.
SUMMARY OF THE INVENTION
The present invention provides a process for substantially extending the useful life of fused silica elements used in high energy ultraviolet optical systems. The fused silica bulk material is pre-compacted by illuminating it with radiation prior to final mechanical fabrication and polishing to the required final surface figure. When the optical element is subsequently used in a high energy ultraviolet environment, it will continue to be compacted but at a lower effective rate. As a result, the useful life of fused silica optical elements can be increased substantially.
In preferred embodiments the fused silica material is precompacted with multiple passes of short-pulse ultraviolet radiation. Multiple passes can reduce precompaction time. In one example useful life of the fused silica is increased from about 150 days to 3.8 years by about 5 days of precompaction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a prior art graph showing compaction versus dose.
FIGS. 2 and 3 relate precompaction dose to useful life dose and allowable compaction.
FIGS. 4 and 5 show sketches of precompaction systems.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Preferred embodiments of the present invention can be described by reference to the drawings.
Precompaction
Applicants have discovered that the useful life of fused silica optical elements such as lenses used for integrated circuit photolithography with ArF 193 nm light sources can be extended very substantially by precompacting the fused silica prior to finishing the optical element. Preferred embodiments of this invention permit sufficient precompaction in a relatively short period of time using a UV light source, to increase useful life by several hundred percent.
As indicated in FIG. 1 and confirmed by experiments performed by Applicants and others the rate of change of compaction with continued UV exposure is gradually reduced. Applicants have determined that compaction by pulse UV radiation is a function primarily of the number of pulses, the intensity of the UV light within the fused silica and the pulse width. Applicants have developed the following formula to express compaction in terms of these parameters:
C=k(NI.sup.2 /t).sup.b
where C is the amount of compaction, measured in parts per million change in the index of refraction of the material;
k is a wavelength dependent constant and which has a value of 0.145 for a UV wavelength of 193 nm, delivered by ArF laser;
N is the number of pulses of laser light, in millions of pulses;
I is the intensity of the light within the material, in mJ/cm 2 ;
t is the integral-square pulse width of the laser pulse, in nanoseconds (10 -9 seconds). The integral square pulse width is defined by: ##EQU1## where T(t) is a function which represents the temporal shape of the laser pulse;
b=an exponent which may depend on the material and wavelength, and typically has values ranging from 0.5 to 0.7. For λ=193 nm and standard fused silica such as Corning 7940, a good estimate of b is: b=0.52.
Applicants call the group of (NI 2 /t) the dose D, and D has the units of [10 6 ×(mJ/m 2 ) 2 /ns]. (ns=nanosecond=10 -9 second). It is the measure of how much irradiation the sample has received. In terms of dose, the compaction C then is given by
C=kD.sup.b
We precompact the sample with a dose D 0 , resulting in a uniform reactive index change δn 0 =kD 0 b , that is: the change before the lens is physically fabricated.
Since δn 0 is done uniformly before the lens is fabricated, it has no effect on the final optical performance of the lens. After the lens is put into service, the change in refractive index caused by continuing UV exposure is:
δn 0 =k(D 0 +D) b ; D being the dose that starts after the precompaction dose D 0 .
The fabricated lens then experiences a further change of index, Δn, over and above the precompaction index change δn 0 :
Δn=δn-δn.sub.0 =k[(D.sub.0 +D).sup.b -D.sub.0.sup.b ].
D represents the dose that the lens must withstand during its service lifetime. If Δn is the maximum amount of further compaction that the optic can tolerate and still meet its imaging performance specifications, the equation can be numerically solved for the required precompaction D 0 . The equation to be solved for D 0 is:
(D.sub.0 +D).sup.b -D.sub.0.sup.b -Δn/k=0. equation 1.
When solving for D 0 we must note that the range of D is constrained by the limiting case D 0 =0, which of course represents no precompaction.
Solutions for equation 1 in this limiting case have been derived as a function of Δn and as a function of D using the values of k and b specified above. The results are shown graphically for these two classes of solution in FIGS. 2 and 3, respectively.
FIG. 2 shows a plot of the required service dose, D, against the required precompaction dose, D 0 , with the parameter Δn being assigned the range of values 0.1, 0.5, and 1.0 ppm. Parameter Δn is the tolerable change in refractive index during the service life of the optic.
As an example of a regime in which precompaction is practical and useful, consider an optic whose maximum allowed Δn is 0.5 ppm.
If no precompaction is performed, D 0 =0 and equation 1 reduces to:
D.sup.b =Δn/k
and
D=(0.5/0.145).sup.1/0.52
D=10.8×10.sup.6 mJ.sup.2 /cm.sup.4 ns
This dose can be converted to number of pulses by:
N=Dt/I.sup.2
If we assume I=0.1 mJ/cm 2 , and
t=30 ns, ##EQU2##
At a pulse rate of 1000 Hz and a duty cycle of 0.25 the lens would last about 150 days.
If, on the other hand, the material from which the lens is fabricated is precompacted with a dose D 0 =100 units (i.e., 10 8 mJ 2 /cm 4 -ns), the service life will be about D=70 units (i.e., 70×10 6 mJ 2 /cm 4 -ns). This represents an extension of useful lifetime (assuming the same I=0.1 mJ/cm 2 , t=30 ns and a 0.25 duty factor) to about 21×10 9 pulses or about 2.7 years. In general, the more sensitive a component is to refractive index changes the more beneficial precompaction becomes.
It should be realized that the service dose D is delivered in a single pass through the lens, while the optic is exposing wafers. In order to maximize lifetime, the optical designer will design the lens so that the intensity I is kept as low as possible. In addition, the producer of the laser source will make the integral square pulse width t as long as possible (typically 30 ns).
By contrast, the setup used to perform precompaction is very different. The light from the source laser can be passed through the optical blank many times, thereby increasing the intensity of the light and increasing the rate of compaction approximately as the square of the number of passes. Equivalently, the precompaction light can be focused into a small high intensity spot, and the sample irradiated in many small area segments, to take advantage of the fact that compaction is a function of intensity squared. In addition, the pulse width of the laser used to do the precompaction can be made as short as possible, typically less than 10 ns. These strategies give great leverage to each pulse delivered by the laser, and lead directly to the preferred embodiments.
Conversely to the equation 1 solutions shown in FIG. 2, in FIG. 3 we see a plot of tolerable compaction versus required precompaction dose; this time the parameter being the required service dose D. Again, as an example of the regime in which precompaction is useful, consider the optic with an allowed compaction is 1.08 ppm. For zero precompaction the lifetime is about 50 units. If, however, it is precompacted to a dose D 0 =100 units, the amount of compaction after the required dose D=50 units will only be 0.35 ppm.
This will allow the optic to run out to D=150 units before reaching the maximum allowable compaction of 1.08 ppm, which translates to an increase in service life (using the above assumptions) of almost 5.7 years.
Precompacting with UV
Applicants have proven that the best way to deliver a precompaction dose to a particular sample is to irradiate small areas in succession, to multipass the photons through the same volume as many times as possible, and to use the shortest possible pulse widths for a given energy. All three of these tenets come from the fact that the induced compaction is a function of the intensity squared. The mathematical basis for this is described below.
Suppose that A is the total cross sectional area of the lens blank to be irradiated.
If the area A is divided up into M subregions for sequential irradiation sessions, the number of pulses, Ns, necessary to deliver a dose D 0 to the subregion is:
Ns=D 0 t/I 2 pulses, where t=laser pulse width and I is the energy delivered per unit area.
Now I=E/(A/M)=EM/A with E being the laser pulse energy, so that the number of pulses needed, Ns, to expose the subregion is:
Ns=D.sub.0 tA.sup.2 /M.sup.2 E.sup.2.
Since there are M subregions, the total pulse count will be:
N=MNs==D.sub.0 tA.sup.2 /ME.sup.2.
Thus, the number of pulses required to compact the entire area A goes as 1/M.
For example, irradiation of the entire area when A=491 cm 2 (diameter of optic=25 cm) is:
N=D.sub.0 tA.sup.2 /E.sup.2 (since M=1).
Further assuming that we want D=100 units and Δn=0.5 ppm (allowed compaction change) the D 0 is 200 from FIG. 2 or FIG. 3, and with a laser pulse width t=10 ns (integral-square definition*) and an E of 50 mJ/pulse, we obtain:
N=192×10 9 pulses. At 1000 Hz and 100% duty factor this would take 6 years.
By comparison, if we divide the area A up into M=100 subregions we get:
N=1.92×10 9 pulses. This requires only about 22 days. With a double pass system as shown in FIG. 4, this time could be reduced to about 5 days.
A dose of 100×10 6 mJ 2 /cm 4 ns at an intensity of about 0.1 mJ/cm 2 and pulse width of 30 ns and a 25 percent duty cycle is equivalent to about 3.8 years of operation as compared to the 150 days in the example given above based on the use of pristine fused silica Thus, 5 days of precompaction can extend the life of a fused silica optical elements from about 150 days to almost 4 years. The 5 day period was calculated based on a double pass.
The system shown in FIG. 4 includes ArF laser 2, beam shaping optics 4, fused silica blank 6 on x and y translation table 8 and mirror 10.
FIG. 5 shows a system for 6 passes through the blank. Mirror 12 should be very slightly tilted so that the return beam does not reenter the aperture (not shown) of beam shaping optics 4.
As explained above, it takes about 100× less laser output energy and 100× less elapsed time to treat the optic in the 100-subregion manner. An additional important benefit to the subregion method is that if the spatial intensity distribution which will illuminate the finished lens is known, the opportunity exists to custom precompact the lens blank to further reduce the effects of continuing compaction in service.
Several techniques are possible for treating the fused silica with the arrangements shown in FIGS. 4 and 5. One technique would be to illuminate one volume until it is completely treated to the required D 0 then move to the next. Another approach is to step the target across a relatively larger area many times or to scan the target continuously in the beam.
Treatment is used damage usually appears first at the beam exit surface of the fused silica blank. Applicants have noted damage at intensity levels of 200 mJ/cm 2 with a 20 ns pulse width but no damage at intensity levels in the range of 80 mJ/cm 2 with 20 ns pulse width. Applicants preferred peak power density for the narrow laser beam is between about 1 MW/cm 2 and about 7.5 MW/cm 2 .
Short and Long Pulse Width Experiments
Applicants have compacted fused silica samples with 30 ns pulses and 13 ns pulses and have confirmed that the shorter pulse width required about half the number of pulses of approximately equivalent energy to achieve the same degree of compaction as the longer pulse width. These results support the general conclusion that precompaction should be done with short pulse width pulses and operation of the stepper-scanner machines should be done with longer pulse width.
Solarization Removal
A second aspect of the invention is the ability to remove solarization induced during precompaction of fused silica. UV radiation on fused silica not only produces compaction as discussed above, it also produces color centers in the material which increases the absorption of the material and reduces the efficiency of the optical elements. This process is called solarization. Solarization is produced in the process of precompaction but Applicants have proven through actual experiments that this solarization can be removed without affecting the precompaction.
In the compaction experiment, a piece of Corning 7940 was exposed at approximately 28 mJ/cm 2 for a total of 711 Mshots. The laser irradiation produced a compaction of approximately 2.7 ppm. The sample was also heavily solarized as evidenced by the bright red fluorescence.
The sample was then put in an oven and heated up to 750° C., held at that temperature for an hour and then allowed to cool slowly over a period of at least 12 hours. This removed all traces of the solarization (no visible red fluorescence any more when placed in laser beam) and all traces of the compaction. The interferogram of the sample then looked exactly the same as when the sample was new--no defects. Glass viscosity varies drastically with temperature. At room temperature the compaction in fused silica is not reversed, even after ten years on the shelf.
The sample was again irradiated, this time at approximately 80 mJ/cm 2 for a total of 69 Mshots. Again, the piece was heavily solarized and showed a compaction of approximately 2.7 ppm (agrees with 1 2 or 2-photon dependence model.) This time the sample was heated up to 400° C., held at that temperature for an hour, and then slowly cooled as before.
This treatment removed all traces of the solarization but removed little, if any, of the compaction as evidenced by the Zygo interferogram. Other bake temperatures and schedules are also possible for optimization of the particular optic being processed.
Persons skilled in the optical arts will recognize that many changes may be made to the specific embodiments shown without departing from the true spirit of the invention. For example, other forms of radiation such as x-ray, gamma ray or neutron radiation could be used to precompact the fused silica. As indicated above, if the radiation is a pulse laser beam, the pulse width should be very short. Lasers with pulse widths of less than 15 ns are readily available. Widths in the range of 10 ns or less are even better. Thus, the scope of the invention is to be determined by the appended claims and their legal equivalents. | The present invention provides a process for substantially extending the useful life of fused silica elements used in high energy ultraviolet optical systems. The fused silica bulk material is pre-compacted by illuminating it with radiation prior to final mechanical fabrication and polishing to the required final surface figure. When the optical element is subsequently used in a high energy ultraviolet environment, it will continue to be compacted but at a lower effective rate. As a result, the useful life of fused silica optical elements can be increased substantially.
In preferred embodiments the fused silica material is precompacted with multiple passes of short-pulse ultraviolet radiation. Multiple passes can reduce precompaction time. In one example useful life of the fused silica is increased from about 150 days to 3.8 years by about 5 days of precompaction. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to the manufacture of a thin film solar panel. More particularly, the present invention relates to the manufacture of a thin film solar panel using a bi-layer process to avoid substrate degradation.
BACKGROUND OF THE INVENTION
[0002] A photovoltaic cell or solar cell converts light energy into electric energy. A standard solar cell includes a transparent substrate, a transparent first electrode, a photoelectric conversion element and a second electrode which are sequentially disposed on a substrate. Typical materials for a transparent substrate are glass and plastic materials.
[0003] Recently, flexible solar panels become popular due to their ease of use, portability and versatility. In a flexible solar panel, polymeric materials, particularly polyimide or poly-ethylene-naphtalate (PEN), and thin metal films such as stainless steel sheet are normally used as substrates. However, due to the different properties of polymers, it is impractical to apply the conventional process for a solar panel with glass to the case with a polymeric substrate or a thin metal film substrate. For example, laser scribing which is commonly used for patterning cells cannot be applied onto a polymer or a thin substrate because the heat generated would seriously damage the polymer or the thin substrate.
[0004] A standard process of fabricating flexible solar panels usually includes interconnecting several small cells together with metallic ribbons to form a higher voltage solar panel. The reason that most people do not take a monolithic approach when making flexible solar panels is that flexible substrates are too fragile to survive laser or mechanical scribing. Other processes, such as standard photolithography, are too expensive to be used in mass production. Therefore, an alternative process for making a flexible solar panel is desired.
SUMMARY OF THE INVENTION
[0005] The present invention provides a novel process for making a thin film solar panel without the use of laser scribing or other heat-generating processes and therefore is particularly useful in making a flexible solar panel.
[0006] The process of the present invention comprises the steps of:
[0007] (a) providing a substrate with patterned first electrodes thereon;
[0008] (b) sequentially depositing a layer of a first material and a layer of a second material on the substrate with patterned first electrodes;
[0009] (c) forming a plurality of patterned photoresists on the layer of the second material and at a plurality of conductive channels;
[0010] (d) wet etching the layer of the first material and the layer of the second material to form a plurality of T-shaped structures at the conductive channels, wherein the etching rate for the first material is higher than that for the second material;
[0011] (e) depositing at least one semiconductor film on the substrate with the patterned first electrodes to form photoelectrical conversion elements;
[0012] (f) depositing at least one second electrode on the semiconductor film, so as to electrically connect the second electrodes to the first electrodes at the conductive channels; and
[0013] (g) scribing the second electrodes and semiconductor film to separate individual cell to form a solar panel.
[0014] Another object of the present invention is to provide an alternative scheme for connecting first electrodes with second electrodes in a solar panel.
[0015] Yet another object of the present invention is to provide a solar panel comprising a T-shaped structure therein.
BRIEF DESCRIPTION OF THE DRAWING
[0016] FIGS. 1( a ) to ( f ) show a schematic process flow for a unit cell according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The present invention is illustrated below in detail by the embodiments with reference to the drawings, which are not intended to limit the scope of the present invention. It will be apparent that any modifications or alterations that are obvious for persons skilled in the art fall within the scope of the disclosure of the specification.
[0018] The first step of the process of the present invention is providing a substrate 11 with patterned first electrodes 12 thereon, as shown in FIG. 1( a ). The patterned first electrodes 12 can be used as front electrodes or back electrodes according to the demands. The materials of the substrate can be materials such as glass, silicon, metal and polymers. In this embodiment of the present invention, the preferred materials are flexible polymers, preferably polyimide or PEN. The making of the patterned first electrodes is a conventional technique and has been discussed in various publications, for example, U.S. Pat. No. 5,334,259. Generally, flexible solar cells are fabricated using substrate architecture due to the lack of transparency of the flexible substrates, such as polyimide.
[0019] In this embodiment of the present invention, the material for the first electrode is a transparent conducting oxide (TCO). Suitable TCO materials include metal oxides of Ag, Al, Cu, Cr, Zn, Mo, Wo, Ca, In, Sn, Ba, Ti or Ni, preferably oxides of Zn or Sn or BaTiO. The TCO layer may be optionally doped with metals such as Al, Ga, Sb, e.g., ZnO:Al (AZO), ZnO:Ga (GZO) and SnO2:Sb (ATO). The TCO is normally patterned by laser scribing or etching techniques. However, when the substrate is a polymer, laser scribing should be avoided because the heat generated by laser scribing causes serious damage to the substrate.
[0020] Unlike conventional process in which a photoelectrical conversion layer is directly deposited on the substrate with patterned electrodes, a layer of a first material 13 and a layer of a second material 14 are sequentially deposited (see FIG. 1( b )). The layers, after patterned in a later step, will serve as masks during the deposition of a semiconductor film. In certain preferred embodiments, the layers also provide a conductive connection between first and second electrodes, which will be described later.
[0021] Suitable first material and second material include, but are not limited to metals, oxides, nitrides, carbon nanotubes or polymers. The selection of the first and second materials is only restricted by the etching selectivity because a T-shaped structure consisting of the first and the second materials should be formed by wet etching. The etching rate to the first material is required to be higher than the etching rate to the second material. Suitable etching selectivity is not limited and is determined by the desired aspect of the T-shaped structure, for example, higher etching selectivity resulting in a T-shaped structure with larger upper portion and lower etching selectivity resulting in a T-shaped structure with relative smaller upper portion. Normally, the etching selectivity of the first material to the second material is in a range of 2:1 to 1000:1.
[0022] In a preferred embodiment of the present invention, the first material is a conductive material so as to provide an electrical connection between first electrodes and second electrodes through the first material even if the first electrodes and second electrodes are not directly connected. The conductive material includes, but is not limited to, metals, carbon nanotubes or conductive polymers.
[0023] In another preferred embodiment of the present invention, both the first and second materials are conductive materials so as to provide an electrical connection between first electrodes and second electrodes through the first and second materials even if the first and second electrodes are not directly connected and the second electrodes are not directly connected to the first material.
[0024] The thickness of the layer of the second material is not critical and is ranging from 100 nm to 30 μm. The thickness of the layer of the first material should be greater than that of the semiconductor film to be deposited later so that the semiconductor film on the T-shaped structure (formed later) and that on the first electrodes are disconnected. This allows the second electrodes to be formed to connect with either the first electrodes or the T-shaped structure at the conductive channels. In one embodiment of the present invention, the thickness of the layer of the first material is at least 200 nm greater than that of the semiconductor film. Moreover, suitable thickness of the layer of the first material is in a range of 300 nm to 30 μm.
[0025] After the deposition of the layer of the first material and the layer of the second material, photoresist is deposited and patterned, so as to form a patterned photoresist 15 . The patterned photoresist 15 is located in the regions where the first electrodes exist, as shown in FIG. 1( c ). Specifically, the patterned photoresist 15 is formed at the conductive channels. The deposition of the photoresist is a skill known in the art and the patterning can be done by any conventional means such as photolithography, printing, slot-coating and maskless laser patterning.
[0026] After the patterning of the photoresist, wet etching is employed. Due to the selectivity of the first and second materials and the isotropic nature of wet-etching, a T-shaped structure is formed. Wet etching by etchants, including chemicals and etching pastes, is also a skill known in the art.
[0027] After the formation of the T-shaped structure at the conductive channels, at least one semiconductor film 16 is then deposited to form photoelectrical conversion elements. The photoelectrical conversion elements can be any types such as single-, tandem- or triple-junction elements and they can be made by any suitable means described in prior art references such as U.S. Pat. No. 5,334,259. It is likely that the first electrodes beneath the T-shaped structures, which serve as masks, are not completely covered by the semiconductor film, i.e., at least part of the surface of the first electrodes are exposed and the width of the region of each first electrode which is not covered by the semiconductor film is typically in a range of 10 to 200 μm. This allows the first electrodes directly connect with the second electrodes at the conductive channels. However, such direct contact of first electrodes and second electrodes is not necessary in certain preferred embodiments of the present invention.
[0028] In one preferred embodiment of the present invention, the first material of the T-shaped structure is conductive so the electrical connection between the first and second electrodes can be done via the first material of the T-shaped structures.
[0029] In an even preferred embodiment of the present invention, both the first and second materials of the T-shaped structures are conductive. Alternatively, the first and the second materials of the T-shaped structures are non-conductive according to the demands. The first electrodes and second electrodes can be electrically connected as long as the first electrodes and the T-shaped structures are not both covered by the semiconductor film.
[0030] In one embodiment of the present invention, the photoelectrical conversion elements are amorphous silicon thin film photovoltaic devices and the amorphous silicon is preferably deposited by DC biased plasma enhanced chemical vapor deposition (PECVD). In another embodiment, the photoelectrical conversion elements are Copper Indium Gallium (di)Selenide (CIGS) thin film photovoltaic devices, and the CIGS is preferably deposited by co-evaporation or co-sputtering. The main point in both cases is that the photoelectrical conversion elements do not entirely block the conductive path between first and second electrodes.
[0031] After the formation of the photoelectrical conversion elements, a conductive film 17 is then deposited as second electrodes. Oblique sputtering is preferred so the regions beneath the T-shaped structures can be filled, as shown in FIG. 1( f ). Other methods with good step coverage capability such as Metal-Organic Chemical Vapor Deposition (MOCVD) can be also applied. The angle of oblique sputtering is not limited as long as the second electrodes contact with the first electrodes or the conductive part of the T-shaped structures. Other process conditions for the manufacture of the second electrodes can be found in prior art references and are similar to the previous descriptions for the first electrodes.
[0032] It should be noted that semiconductor materials are normally sensitive to the environment. For example, when amorphous silicon exposes to the atmosphere, absorbs moisture quickly and the reliability would be significantly affected. According to the process of the present invention, the step of depositing a semiconductor film is directly followed by the step of depositing a conductive film for second electrodes so the duration of the semiconductor film exposing to the atmosphere would be greatly reduced. Thus, the process according to the present invention provides an additional advantage over conventional schemes.
[0033] Finally, the second electrode film and semiconductor film are subject to a laser scribing or an etching, such as etching paste, to separate individual cells (not shown in the figure) and the solar panel is obtained.
[0034] The present invention also provides a solar panel of a novel architecture. The solar panel comprises a substrate, first electrodes, a T-shaped structure which is composed of a first material and a second material on each first electrode, photoelectrical conversion elements and second electrodes.
[0035] A preferred embodiment of the solar panel of the present invention is prepared by the process according to the present invention, which has been described above.
Example
[0036] A polyimide was provided as the substrate. First electrodes were patterned on the substrate by laser-scribing techniques.
[0037] Al was chosen as the first material for this embodiment of the present invention while Ag was chosen as the second material. These two materials were sequentially deposited on the substrate by sputtering or evaporation according to the demands. The thicknesses of the first and second materials were 1 μm and 500 nm, respectively.
[0038] A patterned photoresist was then formed in the regions with the patterned first electrodes, that is, the patterned photoresist is formed at the conductive channel. Wet etching by KOH based etchant was applied to form the T-shaped structure as shown in FIG. 1( d ). The etching rate for Al (the first material) to Ag (the second material) was about 5:1.
[0039] Finally, amorphous silicon film was deposited to form photoelectrical conversion elements by PECVD and Al was deposited by sputtering to form a second electrode layer. The second electrode layer and conversion elements were laser-scribed to form a solar panel according to the present invention. | The present invention provides a process for making solar panels. The process of the present invention avoids the use of laser scribing so it is particularly useful in making flexible solar panels. In addition, the present invention provides an alternative scheme for connecting the first electrodes and second electrodes in a solar panel. | 8 |
BACKGROUND OF THE INVENTION
The invention concerns a procedure for cleaning a double seat valve under the heading of claim 1 and a valve arrangement for implementing the procedure under the heading of claim 8 or 9. A method of the type characterized above is known from DE 31 08 778 C2. This procedure solves the problem of cleaning both seat surfaces of the closing members in a valve of the type under discussion simultaneously. In doing so, the cleansing and/or disinfecting agent is introduced either from outside the double seat valve through the leakage hollow space or through a valve housing part to both exposed seats (compare FIGS. 1-5a of the drawings).
In EP-A-0 208 126, the procedure known from DE 31 08 778 C 2 is further developed in such a way that in a double seat valve equipped with a slider and a seat plate, for the purposes of cleaning the seat of the slide type closing member, the seat is movable only in the direction of the associated valve housing, while the seat plate remains on its seat surface. The cleansing agent is introduced from outside of the double seat valve via the leakage hollow space to the exposed seating surface. This as well as the older procedure contributes to cleansing a relevant double seat valve area, namely the seat area. Nonetheless, in practice it is necessary to include other relevant areas in the cleaning procedure, those of the rod passage guides through the associated valve housing parts.
In valves with slide type closing members, it is necessary to take special precautions so that the compressive forces exerted by the fluid in the conduits upon the closing members can be absorbed. These forces may be compensated for either through suitable measures in the valve drive or through pressure compensating measures on the closing member in the valve housing area (cf. EP-A-00 39 319, FIG. 1; EP-A-0 208 126, FIG. 3.2). The former measure leads to driving gears of relatively large dimensions, while pressure-compensating measures on the closing member naturally require large rod guide passages, which are problematic simply because of their large sealing length with regard to their ability to be cleansed and their safety with reference to mixing product and cleaning fluid.
It is known from EP-A-00 39 319 that a chamber should be placed between the seals of the pressure compensating piston which can be rinsed by cleansing agents. In order to ensure sufficient cleansing agent throughput, there must be a sufficiently large static pressure where the cleansing agent enters. Nonetheless, for safety reasons, it is generally desirable that the cleansing agent is subject to as little pressure as possible on the rod seal facing the interior area of the valve housing. In any case, one must nonetheless take care that at certain time intervals the area behind the seal, with its relatively large circumferential length (into which, because of the actuating movement of the valve, product can occasionally be dragged), and the contact surfaces between seal and rod can be subjected to or irrigated by cleansing agents. It is shown in DE 37 01 027 A1(cf. FIGS. 7 and 8) how two particular sealing points arranged in series on the side of the housing which act together with a slide type closing member whose intermediate space can be rinsed from time to time in the area of one of the sealing points without having to expose the entire seating area of the closing member. While the previously cited figures show a one piece seal with two sealing points, the possibility of seal arrangements with two separate seals follows from the introduction of the description and the claims. Separate cleansing of two seals arranged at a distance on the side of the housing interacting with a slide-like closing member, or with a rod guided out of the valve housing by a partial displacement of the closing member or of the rod for the purpose of exposing one or the other seal to the valve housing part which contains the cleansing agent is explained in greater detail in publication W 0 88/05512(cf. e.g. FIGS. 21, 22; 25, 26 and 59, 60), which claims priority for the above named DE 37 01 0027.
Finally, it is clear from publication DE-U- 88 13 258 how a double seat valve having a closing member constructed as a seat plate and as a slider where the compressive forces on the slider are compensated by a pressure compensation cylinder constructed on the slider can be subjected to a cleansing in the seat region of the slider and in that of the pressure compensation piston guide passage through the valve housing parts with results known from the previously cited publications. It is clear that two parallel cleansing streams (r 1 , r 2 ) branch off from the lower valve housing part. The one (r 1 ) proceeds to the valve region through the exposed seat surface of the slide type closing member over the leakage hollow space and a pipe leading downward from the valve housing part. The other stream (r 2 ) proceeds to this region over the exposed guide for the pressure compensation piston out of the valve housing part.
This well known solution possesses several disadvantages. First, the cleanser stream (r 1 ) which passes through the exposed seat surface of the slide type closing member is difficult to measure, meaning that an uncontrolled waste of cleanser with an associated environmental pollution is not impossible. Second, a second parallel cleanser stream (r 2 ) is necessary to cleanse an additional critical area of the double seat valve, the guide passage area of the pressure compensation piston of the one closing member. In addition, further equally critical areas of the double seat valve remain uncleansed. These areas are, under certain circumstances, the seat area of the closing member constructed as a seat plate, which occasionally comes into contact with product. In any case, these areas include the guide of the closing member activation rod through the overlying valve housing part and the sealing area between the activation rod of the slider-form closing member and the seat plate pipe surrounding this rod.
SUMMARY OF THE INVENTION
Proceeding from the aforementioned disadvantages and state of the art requirements, the present invention seeks to create a procedure of the type characterized in the introduction for ensuring the cleansing the relevant areas of a double seat valve with a minimal and economical use of cleanser and/or disinfectant which last, but not least, is environmentally friendly.
With the proposed procedure it is possible to cleanse the relevant areas of the double seat valve using a single cleansing agent stream, obtained using the partial stroke movement of a slide type closing member on its rod guide passage out of its associated valve housing part. By means of the partial stroke the guide passage (A or C) of the operating rod of the closing member is exposed to the valve housing, permitting the cleanser stream to enter there in order to cleanse the activation rod guide at the branch off point, and at least one of the following areas, the other rod guide passage, the leakage hollow space and the seat area, which has been made accessible.
The proposed procedure can be used to particular advantage in an initial refinement when the two valve housing parts are basically arranged vertically one upon the other and cleansing agent is available in the upper valve housing part. In this case, the cleansing stream cleanses successively, without further branching, in any order (preferably proceeding downward) at least one of the aforementioned relevant areas of the double seat valve. Since the stream is conveyed to the seat area which has been rendered accessible basically as a spray stream, and to the two successive areas as a quasi swarming film under the influence of gravity, no harmful elevations in pressure occur in this proceeding. Nonetheless, this advantageous procedure variant is dependent upon the position of the valves and is hence restricted to a specific if relatively large number of applications.
If, as the proposed method alternatively likewise implies, the cleanser stream can only be obtained at the other, lower rod guide passage (C), whereby at least the upper rod guide (A) is cleansed and subsequently, the cleanser stream continues downward into the seat region which has been made accessible, or into the leakage hollow space, then it is necessary that it be available on the rod guide passage (A) subjected to a sufficiently high pressure in order to assure a sufficiently effective cleansing in the downstream areas. Over against this basic disadvantage stands the advantage generally obtainable by the arrangement in series of the areas to be cleaned that the same cleansing agent stream cleanses all areas, so that the goal pursued by the invention is most effectively reached.
A further advantageous embodiment of the proposed method permits installation of the double seat valve (hereinafter also abbreviated as valve) independently of position, whereby the cleansing agent stream can be obtained from the one as well as the other valve housing part without having to accept the disadvantage of the last mention method. This is accomplished by branching the cleansing agent stream behind the rod guide passage at the branch off point into partial streams R i which cleanse the relevant areas of the double seat valve, which can be arranged side by side or one behind the other. The total stream R and its partial streams R1.sub. are thereby conducted as forced currents into the areas to be cleansed. Thereby it can always be assured that the respective critical rod guide passage is an end point for a partial stream, not an intermediate station.
In most applications, it is sufficient (as one further development of the proposed method provides) to split the total stream R into two partial streams, R 1 and R 2 . One, R 1 , cleanses the seat area which has been made accessible and the leakage hollow space, while the other, R 2 cleanses the other rod guide passage (C) or (A).
A defined adjustment and measurement of the partial stream amounts or the relationship of the partial streams to each other is possible. As a rule, several times the amount of cleansing agent is necessary for cleansing the accessible seat area and the leakage hollow space of the valve than for cleaning .a rod guide passage. For this reason, adjusting the relationship between the these partial streams, for example the partial streams R 1 and R 2 , with R 1 /R 2 > 1, is indicated.
The proposed method may be applied to double seat valves with two slide type closing members and to double seat valves with a slide type closing member and a seat plate. In the latter closing member configuration, the seat plate remains on its seat area and the slide type closing member is moved from it by the partial stroke. The seat area of the seat plate is thus not cleansed in the course of applying the proposed procedure. To the extent that the double seat valve is provided with two slide type closing members, the invention procedurally suggests two partial stroke variants. One variant is characterized by the closing members being moved by opposed partial strokes. The cleansing agent stream branches off at the rod guide passage where the partial stroke runs against the direction of the valve opening. In the other variant, the closing members are moved by partial strokes in the same direction. The cleanser stream branches off at the rod guide passage of that closing member where the partial stroke runs against the opening direction of the valve and which is dependently driven.
It is possible, using a suitable adjustment drive, to implement both forenamed partial stroke variants on the same valve arrangement. Hence it is now possible to guarantee the advantages attainable of the present invention to the full extent in every case on the same valve, regardless of whether the cleansing agent is available in one valve housing part or the other. For the case for example where the valve opens downward and the cleanser is available in the upper valve housing part, while the lower valve housing when necessary is loaded with product, provision of the cleansing agent stream over the upper rod guide passage is obtained by way of an opposed partial stroke movement. Where in the same valve cleanser is available in the lower valve housing part, the lower rod guide passage can be exposed by a partial stroke movement in the same direction against the opening direction of the valve, so that the cleanser stream can now be branched of from the lower valve housing part. The upper valve housing part can thereby at times be loaded with product. Both partial stroke variants allow a displacement of the closing member which at times is loaded with by product in the direction of the product conducting valve housing part. The seat area formerly loaded with product which is covered by the closing member is made available for the cleansing agent stream out of the leakage hollow space.
Cleansing agent is not available in every case which occurs in practice in at least one of the valve housing parts, so that the above proposed procedure cannot be applied. In addition, the method initially suggested is not applicable when product is present in both valve housing parts. Nor is it applicable if a cleansing of the relevant areas of the double seat valve is necessary without restriction in its closed position as well as in restricted form in its open position, namely a cleansing of all areas with exception of the exposed seat areas.
It is known from the initially cited EP-A-0 208 126 that when previously mentioned operating conditions are present, cleansing of the seat surface of the slide type closing member which is if necessary loaded with product takes place by the introduction of cleanser from outside of the double seat valve over the leakage hollow space. A cleansing of the rod guide passages in principle likewise possible by introducing cleanser from outside and under relatively high pressure, which is conducive to an intensive cleaning. It is prohibited for safety reasons. Already at the design level, a seal which on the one hand stands under product load must be prevented from being subject to cleanser under pressure on the other.
In order to ensure a loading with cleansing agent of the rod seal which is possibly loaded with product, introducing the latter to the immediate seal area under as little pressure as possible has been suggested. It is self evident that a cleansing agent subject to pressure conditions of this type cannot be used for further cleaning purposes in a double seat valve. The preconditions for a cleansing of the relevant areas of a double seat valve with minimal, economical and last but not least environmentally friendly use of cleansing and disinfecting agents fail from the start with cleansing technological solutions of this sort. These preconditions consist in the fact the cleansing agent stream cleans all cleansing technologically relevant areas of the double seat valve.
In view of the disadvantages just presented and the state of the art requirements, it is also the goal of the present invention to create a procedure of the type named at the outset which in providing cleanser from the surroundings of the double seat valve solves without restriction the relevant problem of assuring cleansing of the relevant areas of a double seat valve with minimal, economical and lastly (but not least) environmentally friendly use of cleansing and/or disinfecting agent.
The same advantages are attainable for double seat valves in which the cleanser must be introduced from the surroundings of the valve (since in the valve housing no cleanser is available, or operations require the presence of product) with the procedure now proposed as for those double seat valves where the "valve housing" is available as a source of cleansing agent through the partial stroke of the closing member and the associated exposure of a rod guide. The two alternatively proposed procedures differ solely in terms of the position or type of cleanser source. In the method now proposed, the cleanser stream is introduced from outside the double seat valve through an introduction point (E), where it cleanses the rod guide (A or C) on the valve housing side of the introduction point and at least one of the following areas: The other rod guide passage (C or A), the leakage hollow space, and the seat area, or the seat area which has been made accessible.
Since a partial stroke of at least one closing member can be dispensed with because there is no longer a need to expose the rod guidance to the valve housing part, the drive of a double seat valve cleansed in this manner is particularly simple. Indeed the procedural partial stroke variants proposed above may be used without restriction in connection with the cleansing procedure now proposed as well. The same applies for the proposed basic structure of the valve arrangement and advantageous refinements of it.
That the procedure now proposed can use the advantages of the procedure suggested at the beginning almost without restriction results in the final analysis from the fact that it is based upon a fruitful procedural variant of the latter. Among other things, it consists of branching the cleanser stream obtained in the valve or now introduced from the valve surroundings at a branching point (V) into partial streams R 1 . A throttle gap is provided between the branching point and the neighboring rod seal. A partial stream (r) is throttled in the throttle gap. It cleanses the rod seal almost without pressure and is subsequently conducted to the valve surrounding. The other partial stream (R), or the partial streams (R 1 , R 2 ) continue unthrottled from the branching point and clean the other relevant areas of the valve, to be sure basically according to one of the advantageous refinements of the procedure proposed initially.
A refinement of the valve arrangement of almost the same construction for implementing the method now in proposed in the area of the rod guide passage works through the use of a similarly constructed insert between the housing and the pressure compensation piston or pipe. This insert forms on the one hand the necessary throttle gap with the pressure compensation piston or the pipe, and includes on the other a drain hole for draining the partial stream (r) from a chamber adjacent to the rod seal in part formed by the insert into the valve surroundings.
The valve arrangement for implementing the procedure initially proposed finds its most advantageous embodiment when both closing members are constructed as slides and the valve opening direction runs from top to bottom. In this case, the branching off of the cleansing agent at the upper rod guide passage (A) occurs through a partial stroke of the upper slider directed against the opening movement of the valve. At the same time, the lower slide type closing member is displaced downward for a counter partial stroke, so that now both seat surfaces are exposed as before in the closed position of the valve. Cleanser branched off from the upper valve housing part at first cleanses the upper rod guide passage, subsequently proceeding to the exposed seat area and the adjacent leakage hollow space of the valve finally to pass within the pipe extending downward as a drizzle film and from there to exit into the valve surroundings. The valve arrangement for implementing the proposed procedure with branching of the total stream R into two partial streams R 1 and R 2 is characterized by, among other things, that the cleanser stream R obtained at the upper rod guide passage (A), or alternatively at the lower rod guide passage (C), is first conveyed to a branching point, whence it branches into the partial streams R 1 and R 2 . Partial stream R 1 goes to the leakage hollow space of the valve via a connection of the branching point with the ring slot, while partial stream R 2 is conducted from the branching point out of a axially disposed bore in the inside control rod, and from there to the other rod guide passage (C) or else to the rod guide passage (A). The valve arrangement with a branching of the total stream R is, as already presented above, applicable independently of position, especially in a horizontal arrangement as well. The latter is particularly advantageous when such valves are placed at tank discharges. On the one hand, the erection height of the tank is considerably reduced, and on the other, the valve housing part loaded with product can be disposed directly on the tank. The cleansing agent stream at the rod guide passage can be measured under controlled conditions at the point of origin or at another point in the successive path of the stream according to the type of branching. In those valve arrangements in which the cleanser stream is conducted through the valve via a forced flow and subsequently in cleansing the rod guides in branched off into partial streams and the branching off point, the partial stream designated to cleanse the other rod guide passage passes through a throttle gap before reaching this unexposed rod guide passage. This measure assures that no impermissible pressure buildup occurs because of the cleanser on the associated rod seal, which occasionally is loaded by product. The partial stream allotted to the seat areas made accessible and the adjacent leakage hollow space is not critical with regard to pressure buildup, because it enters this area which is associated with the valve surroundings through an aperture of large cross section almost as a free spray stream.
In order to keep the necessary operating forces of the proposed valve arrangements as small as possible, the closing members in the area of their respective associated valve housing parts may be so constructed that the compressive forces exerted by the fluid in the valve housing parts on the closing members are largely compensated. For this purpose, the diameter of the first operating rod is increased to the valve seat diameter in the form of a pressure compensation piston in the area of its guide passage (A).
If the diameter of the pipe associated with the second operating rod is increased in its overall extension area between the closing member and its guide to approach that of the valve seat (as a further advantageous refinement provides), there first result suitable conditions for the formation of a cleanser drizzle film on the inner wall of the pipe in case the cleanser stream, without further branching, successively flows through the cleansing technologically relevant areas of the valve. Second, there result conceivably suitable conditions with respect to avoiding a pressure buildup in the leakage hollow space, for example, as a consequence of defective seat seals or as a result of an unplanned or undesired opening of the upper closing member. In order that the cleanser stream for the above named partial stroke variants can be realized with the same development of the proposed valve arrangement, a remotely controlled connecting opening for draining partial stream R 2 of the cleanser stream is provided in the area above the first rod seal or below the second rod seal. In case partial strokes in the opposite as well as in the same direction are to be implemented in the proposed valve arrangements, the individual partial strokes are subjected to particular measuring criteria, as a further advantageous refinement of the valve arrangement provides in accord with the invention. Exposing the respective rod guide passage necessarily requires on the one hand a particular minimum stroke. On the other hand, this minimum stroke may not be attained if this rod guide passage should not be exposed. The stroke direction in same direction partial stroke motion nonetheless agrees with the direction of the partial stroke for exposing the guide passage because of the necessary exposure of the seat area. In these cases, the respective closing member implements the partial strokes which run indeed in the same direction but are of different magnitude. Since the axial extension of the common seat area of both closing members is nonetheless restricted, and in a partial stroke movement in the same direction the closing members necessarily have a small clearance of the respective end of the seat surface, an advantageous refinement of the valve arrangement provides that the closing members, in relation to their resting position in the closed position of the valve arrangement, are arranged axially displaced in the direction of the second closing member. The partial stroke variant in the same direction is not critical with regard to maintaining necessary clearances from the edges of the seat surfaces, since the closing member adjacent to the edge of the seat surface must accordingly execute a basically greater partial stroke in the same direction partial stroke variant.
BRIEF DESCRIPTION OF THE DRAWINGS
An application of the valve arrangement for implementing the proposed method is presented in the illustration and is described in the following material. The illustrations depict:
FIG. 1, 1a respectively, a cross section through a valve arrangement according to the invention in its closed position, whereby the seal arrangements are designed differently in the first closing member;
FIG. 2, 2a the valve arrangement according to FIG. 1 or la in their open position;
FIG. 3 the valve arrangement according to FIG. 1 in its cleaning position with an exposure of the upper rod guide passage (A) and with a branched cleanser stream (same direction partial stroke movement); FIG. 3a the cleansing position of the valve arrangement according to FIG. 3 with a modified design of the branching point for the cleansing agent in the rod guide passage region (A);
FIG. 4 the valve arrangement according to FIG. 1 in its cleaning position with exposure of the lower rod guide passage (C) and with a branched cleanser stream (same direction partial stroke movement and
FIG. 5 a schematic representation of the partial strokes likewise realizable in the same or opposite direction in the valve arrangement according to FIG. 1.
FIG. 6 a cross section through a valve arrangement according to the invention in the area of the rod guide passage (C) facing away from the control arrangements, whereby the cleanser source is provided in the surroundings of the double seat valve; and
FIG. 7 a cross section through a valve arrangement according to FIG. 6 in the area of the rod guide passage (A) facing toward the control arrangements.
DETAILED DESCRIPTION
A double seat valve (FIG. 1, 1a) whose valve housing 1 is formed by valve housing parts 1a and 1b, has a seat ring 2 passing through these valve housing parts in their connecting area. In the latter, within a cylindrical seat surface 2a, are two slide type closing members 3 and 4 are arranged glidingly displaceable, and over seat seals 13 or 14, radially sealingly displaceable, and over seal 13a or 13, even axially sealingly displaceable toward each other. The lower closing member 4 is extends into a pipe 4a whose diameter is enlarged along its entire extension area between closing member 4 and its guide passage (C) through the lower valve housing part 1b to approximate the valve seat diameter. Pipe 4a forms on the one hand the connection between a leakage hollow space 6 formed between closing members 3 and 4 in the closed as well as the open position of the valve, and the valve surroundings. On the other hand, it forms the pressure compensation cylinder for compensating compressive forces exerted by the fluid in valve housing part 1b on closing member 4. Pipe 4a is sealed off in valve housing part 1b by a second rod seal 7. It is additionally radially conducted via a guiding ring 11 into a tubular insert in valve housing part 1b which is not described in greater detail. Closing member 4 is connected over pipe 4a and a connecting part 4c with a second operating rod 4b conveyed to a control arrangement D which is placed above the valve, but is not shown in the present case. The second operating rod 4b is coaxially enclosed by pipe 4a , whereby within connecting part 4c at least a second supply bore 4f is disposed, which creates a connection between a second chamber 10 below the second rod seal 7 and a bore 4d disposed in axially inside the second operating rod. The first closing member 3 is equipped with a first operating rod 3a constructed as a hollow rod mounted on the second operating rod 4b of the second closing member 4, which widens in its guide passage area (A) through the valve housing part la into a pressure compensation piston 3b enlarged in diameter to the valve seat diameter. This separates a first chamber 8 from valve housing part 1a via a first rod seal 5, whereby a second guide ring 12 acts to guide operating rod 3a which leads out of valve housing part 1 a in the area of components of the guide not described in greater detail, and which finds an extension in connection with pressure compensation piston 3b.
A ring slot 9 formed between the first operating rod 3a and the second operating rod 4b which is guided coaxially therein is connected on the one hand with leakage hollow space 6 and on the other with bore 4d via a first supply bore 4e in the area of its end which faces away from leakage hollow space 6. The first chamber 8 has a first outlet orifice 17 above the first rod seal 5 operable via a remotely controllable first closing arrangement 21. The second chamber 10 is provided with a second outlet orifice 22 below the second rod seal 7 remotely controllable by a second closing arrangement 23. At the end facing away from first rod seal 5 first chamber 8 widens in diameter as a result of an annular groove 3e formed in pressure compensation cylinder 3b, which in the illustrated closing position of the valve is connected via a first throttle gap 15 with an annular space lying above which is not further described. The latter is connected with ring slot 9 via at least one connection bore 3c. Sealing of pressure compensation piston 3b above the first groove 3e toward the valve housing part bordering upon it (not further described) is assured via a third rod seal 18. A fourth rod seal 19 provides for a housing side seal of the first operating rod 3a which extends above the pressure compensation piston 3b. A fifth rod seal 20 between the first and the second operating rod 2a or 4b forms the demarcation of the part of ring slot 9 which stands in connection with leakage hollow space 6. A second annular groove 4g is provided in pipe 4a above the second rod seal 7 which is connected with the second supply bore 4f through a second throttle gap 16. The second annular groove 4g widens into the second chamber 10 in the valve closing position depicted. Another advantageous embodiment of the valve arrangement provides a group of second grooves 4g in this area, whereby the group is formed by grooves separated from one another oriented in the direction of the valve axis, or inclined toward it distributed over the circumference of pipe 4a. An adequate representation at the upper rod guide passage is Visible in FIG. 3a. The areas of the double seat valve relevant in the course of applying the proposed method are characterized in a particular manner by (A), (B) and (C). The guide passage of the first operating rod 3a(in the region of its pressure compensation piston 3b) carries the designation (A). The leakage hollow space 6 and the adjacent seat area which is to be made accessible to the cleanser stream is designated (B), and the guide passage of pipe 4a through the lower valve housing part 1b bears the designation (C). The equilibrium position clearance of closing members 3 and 4 is designated with a, possible same or opposite direction partial strokes bear the designation T ii , and H designates the opening direction or the opening stroke of the valve arrangement.
FIG. 2 and 2a depict the open position of the proposed valve arrangement, whereby closing members 3,4 are displaced downward out of their seat surface 2a and their equilibrium position clearance a for the opening stroke H. In the embodiment according to FIG. 2a the first seat seal 13 has in first closing member 3, in addition to its radial sealing action toward seat surface 2a on contact of closing members 3,4 with each other, an additional sealing action oriented in an axial direction toward the second closing member 4, so that the leakage hollow space 6 is likewise closed to second valve housing part 1b . This embodiment guarantees an almost leakagefree operation of the valve arrangement, as the space between closing members 3,4 when brought together on the one hand and seat surface 2a on the other is minimized. Outlet orifices 17 and 22 are opened in the present case, since the remotely controlled closing arrangement is not actuated. A closure of this outlet orifice would nonetheless be equally possible in this valve position.
It is apparent from FIGS. 3 and 3a that in a displacement of the first closing member 3 by means of its operating rod 3a for partial stroke T 11 in the direction of valve housing part 1a that the sealing point of the pressure compensation piston which acts in concert with the first rod seal 5 in the closed position of the valve is likewise displaced for this partial stroke in the direction of first chamber 8. At the same time, the second closing member 4 is displaced by its operating rod 4b by the opposed partial stroke T 21 . The pressure compensation piston 3b is necessarily so constructed in the region of first rod seal 5 that the guide passage (A) to the first chamber 8 is exposed with partial stroke T 11 so that a cleanser stream R branches off from the valve housing part and is guided through the exposed guide passage (A) and into adjacent first chamber 8. From thence, the stream proceeds to ring slot 9 via connection bore 3c. Here it branches at branching point V into partial streams R 1 and R 2 . Partial stream R 1 proceeds via the extending ring slot 9 into leakage hollow space 6 and the adjacent seat area 2a, which has been made accessible. Both areas are designated (B). Partial stream R 2 flows over first supply bore 4e into bore 4d, from there over the second supply bore 4f and the second throttle gap 16 of second chamber 10 below the second rod seal 7. Pipe 4a and the first guide ring 11 can be so dimensioned to each other that the passage of a relatively small partial stream ra into the valve surroundings is possible, while the remaining, basically larger component R 2 , flows off via the second outlet orifice 22. In the area of leakage hollow space 6, partial stream R 1 is guided to the adjacent seat surface 2a, made accessible for same direction partial strokes T 11 and T 21 , passing from the free seat surface of closing members 3,4 with their equilibrium clearance a. After the first area relevant for cleansing technology, guide passage (A), is subjected to cleansing, the second and third areas, (B) and (C), are thereby subjected to such in a quasi parallel fashion. Outlet orifice 17 is closed by closing arrangement 21, so that the cleanser stream obtained at the guide passage (A) is compelled to enter into cleansing technologically relevant areas (B) and (c).
In case cleansing of the labyrinthine first chamber 8 which branches to outlet orifice 17 is indicated, a relatively small partial stream r can be admitted via outlet orifice 17. This partial stream must be taken into account in apportioning total stream R (increased to R,). The first recess 3ein pressure compensation piston 3b is so positioned in relation to the third rod seal 18 that an unimpeded passage of cleansing agent stream R from first chamber 8 into ring slot 9 is possible. The first throttle gap 15 is passed around almost as in a bypass, so that cleansing stream R remains unthrottled at this point. By way of contrast, second throttle gap 16 fulfills its throttle role and impedes partial stream R 2 from causing any impermissible pressure buildup on second rod seal 7, which may be loaded with product.
The alternative cleansing method, in which the cleansing stream R is branched off at guide passage C of pipe 4a through partial stroke T 22 of the second closing member 4 by means of its operating rod 4b in the direction of the first valve housing part from lower valve housing part 1b is presented in FIG. 4. At the same time, there follows a same direction displacement of first closing member 3 by its operating rod 3a for partial stroke T 12
It is advantageous to dimension pipe 4a in the region of the first guide ring 11 so that there a relatively small partial stream r 1 of cleansing agent can emerge into the valve arrangement surroundings. Depending upon the size of this partial stream, a cleanser stream R, is branched off at guide passage C of pipe 4a in the second valve housing part 1b , assuring the necessary cleanser stream R for the other two areas A and B. The stream arrives unthrottled via second recess 4g in the region of second rod seal 7 at second supply bore 4f and from thence in bore 4d to enter ring slot 9 from her via first supply bore 4e. A branching into partial streams R 1 and R 2 at branching point V in the connection bore 3c region. Partial stream R 1 flows into leakage hollow space 6 and adjacent exposed seat area 2a, as previously depicted in FIG. 3. Partial stream R 2 arrives in first chamber 8 via first throttle gap 15, the chamber being sealed off from the annular space above pressure compensation piston 3b by third rod seal 18. Outlet orifice 17 is open, so that cleansing agent stream R 2 can emerge in the valve arrangement surroundings out of cleansing technologically critical area (A) above first rod seal 5. Since partial stream R 2 necessarily must pass first throttle gap 15, an impermissible pressure buildup in cleanser stream R 2 above first rod seal 5, if necessary loaded by product, is safely avoided.
Components and designations indicated in FIGS. 2-4, but not further explained in their associated description, or components indeed mentioned in the description, but not drawn in the Figures are discussed in detail in the descriptions for FIGS. 1 and 1a. To the extent that the interior space of valve housing parts 1a,1b is referred to by P, this means that product can on occasion be present there during the cleaning procedure. To the extent that the alternative cleansing procedures should be applied optionally, as needed, by exposure of guide passage (A) or guide passage (C), outlet orifices 17 and 22 may be opened and closed by remote control for discharging partial stream R 2 .
Partial strokes necessary for the alternative cleansing procedures are depicted in FIG. 5. The axial extension of seat surface 2a is referred to as S and the opening direction of the valve arrangement as H. The left part of the illustration shows the first and second seat seal 13 or 14 in their equilibrium position, that is, in the closed position of the valve arrangement, whereby equilibrium clearance a is provided. It is clear that seals 13, 14 and thereby closing members 3,4 are arranged axially displaced in the direction of the second closing member 4 within seat surface 2a. In the middle illustration, seals 13, 14 assume their respective outer end positions when they are displaced for opposed partial strokes T 11 or T 21 . First seat seal 13 has thereby a marginal clearance b 1 to the upper end of seat surface 2a, while second seat seal 14 has a marginal clearance b 2 to the lower end of seat surface 2a. In the right hand illustration, closing members 13, 14 are displaced from their equilibrium position for same direction partial strokes T 12 or T 22 .
It is further evident that partial strokes T 11 and T 21 or T 12 and T 22 are different. This necessarily results from the fact that guide passage (A) must be opened by partial stroke T 11 , while partial stroke T 21 merely causes the exposure of the seat surface of second closing member 4, which can be loaded by product. Partial stroke T 11 is hence larger than partial stroke T 21 (on this, cf. also FIG. 3).
The opening of guide passage (C) of pipe 4a takes place in same direction partial stroke movement (compare the right hand illustration in FIG. 5 and Figure.4) by partial stroke T 22 , while T 12 again merely exposes the seat surface of first closing member 3. For this reason, partial stroke T 22 is here designed to be greater than partial stroke T 12 , whereby it is assured, however, that after completion of same direction partial strokes T 12 and T 22 , the second closing member 4 is not in the very position which first closing member 3 previously occupied in its closed position before it completed partial stroke T| 12 . To ensure satisfactory cleaning of the first closing member 3, second closing member 4 should not yet have reached the closed position of first closing member 3 following completion of partial stroke T 22 . A sufficient safety clearance a, is provided.
The previous exposition necessarily leads to the conclusion that closing members 3, 4 in their closed position cannot be grouped around the axis of symmetry which is vertically oriented toward the rotation axis of seat ring 2. Rather, they are positioned asymmetrically in seat ring 2.
The proposed method and the valve arrangements presented as suggestions for its implementation now in fact make it for the first time possible to subject all relevant areas of a double seat valve to cleansing with a single cleansing agent stream successively, or by branching the stream behind the exposed guide passage, also parallel or in series, with minimal, economical and environmentally friendly sue of cleansing and/or disinfecting agents.
The procedures in accord with the invention are indeed not solely applicable to the concretely proposed valve arrangements above. They are also valid for the majority of the closing member configurations, opening directions and partial stroke variants which have become known in the publications mentioned above. They are, as already explained, applicable to double seat valves which are equipped on the one hand with a seat plate and with a slide type closing member on the other. Only those arrangements are to be excluded in view of the requirement for leakage free operation in which the slide type closing member executes a "collection movement" in the direction of the seat plate in the course of the opening movement of the double seat valve (on this see DE 31 08 778 C29). With respect to the control arrangements for the operating rods which guarantee the proposed methods, the only requirement is that these must permit the opening movement of the double seat valve with the opening stroke H on the one hand, and that on the other, they must permit the opposite direction partial strokes T 11 , T 21 or the same direction partial strokes T 12 , T 22 in realizing alternative cleaning procedures on the same valve arrangement.
The position of branching point V is selected in the form of construction only as an example. Instead of its arrangement in ring slot 9, the point can also be provided at another place in the valve in transporting cleanser over bore 4d preferably between the end and the guide passage (A). If, for example, it is positioned near the guide passage (A), a partial stream directed through a throttle position 15 can almost be guided without pressure from here to the rod seal of guide passage (A) and further into the valve surroundings, while the other partial stream from branching point V cleanses the major portion of the rod guide passage (A) unthrottled, and is brought via ring slot 9 to leakage hollow space 6 and seat area 2a, which has been made accessible. In the closed and open position of the valve, the connection of the area immediately behind the valve seal (A) with the valve surroundings via outlet orifice 17 (which is basically designed for the discharge of the cleanser stream) almost represents a leakage control opening which provides information on the status of the rod seal.
It is not necessary to go into the basic construction of the valve arrangement in FIGS. 6 and 7, as they have been sufficiently explained in FIGS. 1-4. Only particularities in the rod guide passage area need to be discussed.
An insert 24 is placed between pipe 4a and a housing which is not further described, which forms with pipe 4a the throttle gap 16 and contains a discharge bore 24b for draining partial stream (r) out of a chamber 24b adjacent to rod seal 7 and partially formed by insert 24 into the valve surroundings (FIG. 6). A similarly constructed arrangement is found in FIG. 7. Throttle gap 15 is here formed between insert 24 and pressure compensation piston 3b.
A first flow path guide 25 is placed below insert 24 (FIG. 6) which brings the cleansing agent (R+r) introduced via an introduction point (E) to the region of the lower end of pipe 4a , diverts it, and subsequently cleanses a part of the jacket surface of pipe 4a . The cleanser stream (R+r) branches into partial streams (R) and (r) at the branching point (V). Partial stream (r) is subjected to throttling in throttle gap 16 and arrives almost pressureless in neighboring rod seal 7 to pass via discharge bore 24a into the valve surroundings. Partial stream (R) flows unthrottled over supply bore 4f to other relevant areas of the valve in order to be subjected to further treatment in accord with the proposed method. A guide and wiper part 27 impedes the introduction of crude contamination form the valve surroundings into the valve guide passage region and serves, if necessary, for guiding pipe 4a .
The cleansing agent stream (R+r) introduced via the introduction point (E) in the upper rod guide passage area (A) from the valve surroundings branches at branching point (V) into partial streams (R 1 , R 2 ) and into partial stream (R), whereby the last mentioned already takes the basic course depicted in FIG. 6, in this case to rod seal 5 and from there to the valve surroundings. A second flow guidance part 26 serves to separate and convey unthrottled partial streams (R 1 and R 2 ). A first and a second range spacer 26a or 26b provide for unequivocally specific passage cross sections and sufficiently defined current and pressure formation in the gaps on both sides of the second flow guide part. Partial stream R 1 arrives in ring slot 9 via connection bore 3c. Partial stream R 2 flows through a second connection bore 3f and the first supply bore 4e to bore 4d to clean the other rod guide passage (C) there.
The introduction and distribution system for the cleanser stream introduced from the valve surroundings depicted in FIGS. 6 and 7 is not dependent upon the manner in which this cleanser stream is further processed in the remaining course through the double seat valve. In the further course a number of modifications are possible. A operation of the areas relevant for cleaning technology purely in series is possible, as a purely parallel operation, or a mixed in series and parallel operation. | Described are a procedure for cleansing double seat a valve, especially one operating with low or no leakage, and a valve arrangement for implementing the procedure which guarantees, among other things, that the cleansing of the relevant areas of the double seat valve is possible with a minimal, economical and environmentally friendly use of cleansing or disinfecting agents. In terms of industrial process engineering, among other things, a partial stroke of a closing member exposes a guide passage (A or C) in such a manner that the cleanser stream (R) branches off via the exposed guide passage (A or C) out of the valve housing part (1a or 1b), thereby cleansing the guide passage (A or C), and at least one of the following areas, the other guide passage (C or A), the leakage hollow space (6), and the seating surface (2a) which has been made accessible. For implementing the procedure it is suggested, among other things, that a bore (4d) be provided in axial alignment in the second rod (4b) which is connected with the guide passage (A) on the one hand and with guide passage (C) on the other. It is also proposed that the transmission path between the bore (4d) and the guide passage (A) contain a branching point (V), from which a further connection is created to an ring slot (9) formed between the first rod (3a) and the second rod (4b) which is coaxially conveyed in the first. It is suggested that the ring slot (9) provide a connection to the leakage hollow space (6). The cleanser stream (R) should be released, branching into partial streams (R 1 , R 2 ) at the branching point (V) (Figure 3a), by exposure of the guide passage (A) by a partial stroke of the first closing member (3) against the opening movement (H) of the valve, or of guide passage (C) by a partial stroke of the second closing member (4). | 8 |
TECHNICAL FIELD
This disclosure relates to the field of transmission systems. More particularly, the disclosure pertains to a manual transmission with a clutch controlled by a controller in response to movement of a clutch pedal.
BACKGROUND
A typical manual powertrain is illustrated in FIG. 1 . Solid lines represent mechanical power flow through rotating shafts. Dashed lines represent control connections, which may be implemented using mechanical linkages. Engine 10 generates power at crankshaft 12 by burning fuel. The engine responds to changes in the position of accelerator pedal 14 to generate more power when the pedal is depressed further by the driver. Transmission 16 transmits power from crankshaft 12 to output shaft 18 . Transmission 16 includes a friction clutch 20 and a gearbox 22 connected by input shaft 24 . Gearbox 22 is capable of establishing a variety of forward speed ratios and at least one reverse speed ratio in response to driver manipulation of shifter 26 . The driver controls the torque capacity of clutch 20 by manipulation of clutch pedal 28 . Differential 30 splits power from output shaft 18 between a left axle 32 driving a left wheel 34 and a right axle 36 driving a right wheel 38 while permitting slight speed differences between the axles as the vehicle turns a corner. In a typical rear wheel drive powertrain, the transmission output shaft is a driveshaft that extends to the differential. In a typical front wheel drive powertrain, the output shaft 16 may be driveably connected to the differential by a final drive gear. The transmission and differential of a front wheel drive powertrain are frequently combined into a single housing and called a transaxle.
For internal combustion engine 10 to generate power, crankshaft 12 must rotate at sufficient speed. However, when the vehicle is stationary with gearbox 22 establishing a speed ratio, input shaft 24 is also stationary. In order to start the vehicle moving, the driver controls the torque capacity of clutch 20 to transmit power from moving crankshaft 12 to stationary input shaft 24 . As the vehicle accelerates the speed of input shaft 24 gradually increases until it is equal to the speed of crankshaft 12 , at which point clutch 20 can be fully engaged. With clutch 20 fully engaged, the speed of crankshaft 12 is proportional to vehicle speed. As the vehicle accelerates in 1st gear, the speed of crankshaft 12 becomes excessive, necessitating a shift to 2nd gear. Gearbox 22 is not capable of changing ratios while transmitting power. Therefore, the driver shifts by disengaging clutch 20 , then manipulating shifter 26 to change the gearbox ratio, then re-engaging clutch 20 . Re-engagement of clutch 20 forces the crankshaft speed to become equal to input shaft speed, predominantly by changing the speed of the crankshaft.
Whenever clutch 20 transits torque between shafts rotating at different speeds, as during a vehicle launch event, some power must be dissipated. Power is the product of speed and torque. During a launch event, the torque exerted by the crankshaft and the torque exerted on the input shaft are both equal to the clutch torque capacity. The power flowing into the clutch is the torque capacity multiplied by the crankshaft speed. The power flowing out of the clutch mechanically is the torque capacity multiplied by the input shaft speed. The difference between the power inflow and the mechanical power outflow is dissipated by conversion into heat. Initially, the heat is absorbed into clutch components causing the temperature of those components to increase. Then, the heat is gradually transferred to the environment through convection, conduction, and radiation, gradually reducing the temperature of the clutch components.
The amount of energy dissipated by the clutch in a time interval is equal to the integral of the power dissipation over time. If an excessive amount of energy is dissipated in a short amount of time, the clutch temperature will rise excessively. When the clutch temperature is elevated, the rate of wear of the clutch facing material increased dramatically. At sufficiently high temperatures, the friction coefficient of the material decreases and the clutch may be incapable of achieving sufficient torque capacity. Driver technique in manipulating the accelerator pedal, clutch pedal, and shifter strongly influences energy dissipation.
SUMMARY OF THE DISCLOSURE
A vehicle includes an engine, a clutch, a gearbox, and a controller. The gearbox establishes one of a plurality of power flow paths between an input shaft and an output shaft in response to movement of a shift lever. The clutch transmits torque from the engine to the input shaft with a torque capacity that varies in response to a position of a clutch actuator. The torque capacity is negligible when the actuator position is on a released side of a touch point and increases monotonically with respect to actuator positions on an engaged side of the touch point. The controller adjusts the actuator position according to a function of a clutch pedal position. During a first launch event, the controller monitors a sensor array and modifies the function in response to the received signals. The sensor array may include a torque sensor, a rotational speed sensor such as a Giant Magneto Resistive (GMR) sensor, or an acceleration sensor. During a second launch, the controller adjusts the actuator position according to the modified function of the pedal position. The function modified such that, as the touch point changes due to wear or other effects, the touch point corresponds to a constant, predetermined clutch pedal position. Under certain conditions, the controller may adjust the actuator to the released side of the touch point while the clutch pedal is on an engaged side of the constant, predetermined position. These conditions include coasting with the accelerator pedal released and the vehicle being stationary with the transmission engaged in a forward drive power flow path. In some circumstances, the controller may shut the engine off while the clutch actuator is in a released position and may maintain the actuator in a released position, independent of the clutch pedal position, until the engine is restarted.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is schematic illustration of a vehicle powertrain having a manual transmission.
FIG. 2 is a schematic illustration of a vehicle powertrain having a manual transmission with an electronically actuated clutch.
FIG. 3 is a schematic diagram of a gearing arrangement for a manual transmission.
FIG. 4 is a cross section of an electronically actuated manual transmission clutch in a disengaged position.
FIG. 5 is a cross section of an electronically actuated manual transmission clutch at a touch point position.
FIG. 6 is a cross section of an electronically actuated manual transmission clutch in an engaged position.
FIG. 7 is a graph of clutch torque capacity as a function of clutch actuator position.
FIG. 8 is a flow chart for a method of adaptively updating a touch point estimate using a clutch torque measurement.
FIG. 9 is a flow chart for a method of adaptively updating a touch point estimate using an acceleration measurement.
DETAILED DESCRIPTION
Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.
FIG. 2 illustrates a powertrain that utilizes a controller to add features not practical in the purely manual powertrain of FIG. 1 . In the powertrain of FIG. 2 , engine 10 and clutch 20 do not respond directly to movement of the accelerator pedal 14 and the clutch pedal 28 respectively. Instead, controller 40 senses the position of the pedals and sends commands to the engine and clutch. In some instances, the commands may not correspond directly to driver commands as indicated by manipulation of the pedals. To assist in determining the proper commands, the controller may receive additional signals, including a signal indicating the position of shifter 26 and signals from an array of sensors 42 in gearbox 22 .
FIG. 3 illustrates an exemplary configuration of a front wheel drive transmission. Transmission output 18 is a final drive ring gear fixed to a carrier of a differential. Two countershafts, 50 and 52 are parallel to transmission input shaft 24 . Final drive pinion gears 54 and 56 are fixed to countershafts 50 and 52 respectively and mesh continuously with output gear 18 . Therefore, the speeds of the countershafts are related to the speed of output 18 by fixed ratios. A number of gears fixed to input shaft 24 mesh with corresponding gears that are supported for rotation about one of the countershafts. Particular gear ratios are engaged by moving one of the synchronizers 58 , 60 , or 62 , to selectively couple one of these gears to one of the countershafts. A shift mechanism (not shown) moves the synchronizers in response to driver manipulation of the shifter 26 .
The transmission also includes a number of sensors which respond in various ways to clutch torque. These sensors collectively make up sensor array 42 . Several methods of determining torque are described below, although only one method of determining torque is required. Particular embodiments may determine torque using a subset of the sensors shown in FIG. 3 or may utilize different sensors that respond to clutch torque. Torque sensor 64 directly senses the torque on input shaft 24 which, when clutch 20 is slipping, is equal to the clutch torque capacity. For example, torque sensor 64 may measure the shear strain in the shaft.
Two Giant Magneto Resistive (GMR) sensors 66 and 68 are located at opposite ends of countershaft 50 . GMR sensors generate a voltage that varies sinusoidally based on the rotational position of a magnet fixed to the end of a shaft. GMR sensors provide a rotational position measurement accurate to a fraction of a degree at intervals of around 50 micro-seconds. Unlike the speed sensors commonly used in transmissions, GMR sensors can provide a usable signal even when the shaft is at zero speed. One limitation of GMR sensors is that they must be mounted at the end of a shaft. However, in this application, that is not a problem.
When either 1st or 2nd gear is selected, at least a portion of countershaft 50 will transmit torque that is proportional to the clutch torque. The portion of the shaft transmitting the torque is twisted as a result of the torque. The amount of twist can be measured by measuring rotational position of each end of the shaft and taking the difference. The clutch torque is proportional to this difference. The coefficient of proportionality differs between 1st and 2nd gear.
Due to the accuracy of GMR position signals, an accurate and stable speed signal can be obtained by differentiating the position signal. In turn, an accurate rotational acceleration signal can be obtained by differentiating the rotational speed signal. The acceleration of countershaft shaft 50 is proportional to vehicle acceleration, independent of which gear ratio, if any, is selected. Vehicle acceleration is related to proportional to clutch torque, the selected gear ratio, and inversely proportional to vehicle mass. Since the selected gear ratio is known to the controller and the vehicle mass typically changes relatively slowly within a narrow range, vehicle acceleration can be used as a surrogate for clutch torque for some purposes. Vehicle acceleration also responds to additional factors such as road grade, wind, and road resistance. These factors also tend to change relatively slowly such that the controller can compensate for them. Deriving a surrogate torque signal based on vehicle acceleration requires only one of the GMR sensors 66 or 68 .
FIG. 4 shows a cross sectional view of a clutch 20 . A clutch disk 70 is splined to gearbox input shaft 24 . In some embodiments, clutch disk 70 may include a damper to provide torsional isolation between the engine and driveline when the clutch is engaged. Friction material 72 is attached to the front and back sides of clutch disk 70 . A flywheel 74 is fixed to crankshaft 12 . In some embodiments, the flywheel may include provisions for torsional isolation. A pressure plate 76 is supported for rotation with the flywheel, but allowed to move axially. A clutch cover 78 is fixed to the flywheel. A diaphragm spring 80 is attached to the clutch cover 78 . In its natural state, diaphragm spring 80 is conical is shape such that it tends to push the pressure plate to compress the clutch disk between the pressure plate and the flywheel. However, in the disengaged state shown in FIG. 4 , an actuator 82 has pushed the center of diaphragm spring inward such that the spring assumes a more flat shape, allowing for slight separation between the friction material 72 and the flywheel and pressure plate. Since actuator 82 does not rotate and diaphragm spring 80 rotates with the flywheel, they are separated by a bearing 84 .
FIG. 5 shows the clutch with the actuator moved to the touch point. At the touch point, the pressure plate has moved toward the flywheel enough to eliminate the space such that the friction material 72 is in contact with the flywheel and pressure plate, but the normal force compressing the friction material is zero. Since the normal force is zero, the torque capacity of the clutch is zero at the touch point. FIG. 6 shows the clutch with the actuator moved beyond the touch point. As the actuator position moves beyond the touch point, the normal force compressing the friction material increases. Consequently, the torque capacity of the clutch also increases.
FIG. 7 illustrates the relationship between actuator position and torque capacity. Line 90 indicates the relationship for a new clutch. The torque capacity is zero when the actuator position is less than the touch point 92 and the increases steadily as actuator position increases. Controller 40 determines a desired torque capacity based on clutch pedal position, among other inputs, and uses information about the relationship between actuator position and torque capacity to determine what actuator position to command. As the clutch is used, the friction material 72 gradually wears away. Line 94 illustrates the relationship for the same clutch after significant friction material wear has occurred. The touch point 96 increases as the clutch wears. In addition to clutch wear, other noise factors such as temperature may shift the touch point. If the controller uses an incorrect estimate of the touch point, the torque capacity may differ substantially from the desired torque capacity.
The clutches of some manual transmissions are equipped with mechanical wear compensators that shift the touch point back such that it corresponds to roughly the same clutch pedal position. However, mechanical wear compensators tend to make the adjustments in discrete steps. These discrete steps are small enough that drivers typically do not notice. However, to a controller capable of finer control, unpredictable adjustments create an additional noise factor. Therefore, it is desirable to replace the mechanical wear compensation devices of manual transmissions with algorithmic wear compensation.
FIG. 8 is a flow chart for adaptively determining the actuator position corresponding to the clutch touch point when a clutch torque signal is available. The method is executed, beginning at 100 , at regular intervals. If the clutch is not slipping, as determined at 102 , the method proceeds to 104 to update the current actuator position without updating the touch point. For example, the actuator position may be set according to a function of a sensed clutch pedal position such that a predetermined pedal position places the actuator at the estimated clutch touch point. If the clutch is slipping, the method proceeds to 106 to measure the clutch torque using one of the methods described above or some other method. Equivalently, the method may measure a quantity that is directly proportional to clutch torque, such as a transmission shaft torque. If the measured clutch torque is less than a threshold at 108 , the method branches based on a conclusion that the current actuator position is less than the actual touch point. The threshold is set near zero, but large enough that sensor variation does not falsely conclude that the clutch is in the transmitting torque. At 110 , the current estimate of the touch point is compared to the current actuator position. If the estimate of the touch point is less than the current position, then the estimate of the touch point is updated at 112 to be equal to the current position. Then, the current position is updated based on the function of pedal position and the revised estimate of the touch point. Alternatively, updating the function based on the revised clutch point may be delayed until after the current event, such as a vehicle launch event or a shift is completed. If the measured clutch torque exceeds the threshold at 108 , on the other hand, the method branches based on the conclusion that the current actuator position is past the touch point such that the clutch torque is responding linearly to changes in actuator position. If that conclusion is inconsistent with the current estimate of the touch point, as determined at 114 , then the estimate is updated at 112 and the current position is updated at 104 .
FIG. 9 is a flow chart for adaptively determining the actuator position corresponding to the clutch touch point when a vehicle acceleration signal is available. As with the method of FIG. 8 , the method is executed, beginning at 100 , at regular intervals. If the clutch is not slipping, as determined at 102 , the method proceeds to 104 to update the current actuator position without updating the touch point. If the clutch is slipping, the method proceeds to 120 where the method records the acceleration measurement of the previous execution of the method, corresponding to a previous actuator position. At 122 the method measures vehicle acceleration or a quantity that is directly proportional to vehicle acceleration such as the acceleration of a transmission shaft. At 124 , the method calculates the slope of the relationship between acceleration and actuator position between the previous execution of the method and the current execution. If the clutch position is less than the touch point, this slope would nominally be zero. If the clutch position is greater than the touch point, the slope will be related to the gear ratio. If the computed slope is less than a threshold at 126 , the method branches based on a conclusion that the current actuator position is less than the actual touch point. Different thresholds may be used when different gear ratios are selected. Furthermore, an absolute value may be used when reverse gear is selected. At 128 and 130 , the current estimate of the touch point is updated if it is less than both the current and the previous position. If the computed slope is greater than the threshold at 126 , the method branches based on a conclusion that the current actuator position is greater than the actual touch point. At 132 and 134 , the current estimate of the touch point is updated if it is greater than both the current and the previous position. At 136 , the current actuator position is recorded for use in the next execution. Then, the current position is updated based on the pedal position.
If the actual touch point changes, the methods of either FIG. 8 or FIG. 9 will result in a change in the estimate of the touch point following a clutch engagement event. As a result, the controller will modify the function that relates commanded actuator position to sensed clutch pedal position. Then, during a subsequent launch or shift event, the actuator position will be different for a given clutch pedal position. As the clutch wears, or as other noise factors influence the actual touch point, the function may be modified such that the pedal position at the clutch touch point remains nearly constant.
Although the nominal behavior of the controller is to position the actuator based solely on the position of the clutch pedal, the controller may depart from this behavior is some circumstances. The ability to over-ride the driver clutch pedal movement is one of the advantages of an electronically actuated clutch. One such circumstance occurs when the vehicle is coasting (neither accelerator pedal nor brake pedal depressed) and the driver leaves the transmission in gear with the clutch pedal released (which corresponds to the clutch being engaged). In this circumstance, vehicle inertia causes the engine to rotate. This causes the engine to exert drag torque which may be substantial if the engine speed is relatively high. To prevent the vehicle from decelerating unnecessarily, the controller may move the clutch actuator to a released position and then control the engine to rotate at idle speed. Alternatively, the controller may shut the engine off to reduce fuel consumption further. When the driver depresses the accelerator, the controller must quickly bring the engine back to synchronous speed and then re-engage the clutch. In order to be able to re-engage quickly, the controller positions the actuator close to the touch point, but on the released side of the touch point. For the controller to accomplish this, it must have accurate information about the location of the touch point.
When the vehicle is stopped, the controller may shut the engine off to save fuel. The controller must then quickly restart the engine when the driver releases the brake pedal and depresses the accelerator pedal. Some manual transmission drivers waiting at a stop light disengage the transmission with shifter 26 and release clutch pedal 28 . When they are ready to drive away, they depress the clutch pedal 28 , engage 1st gear with shifter 26 , and then step on the accelerator pedal 14 and gradually release clutch pedal 28 . These sequential steps give the controller sufficient time to restart the engine before the driver begins releasing the clutch pedal. However, other drivers leave the transmission in 1st gear and depress clutch pedal 28 while waiting at a stop light. If the controller stops the engine in this circumstance, the driver may begin releasing the clutch pedal before the controller has started the engine. If the driver engages the clutch before the engine is started, that will prevent a proper engine start. With the electronically actuated clutch described herein, the controller can prevent engagement of the clutch until the engine has restarted. Therefore, the controller can stop the engine in more conditions than otherwise, reducing fuel consumption. Specifically, the controller moves the actuator to a released position near the touch point while the engine is shut down and maintains the actuator in that position, regardless of clutch pedal position, until the engine has restarted.
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments can be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics can be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and can be desirable for particular applications. | A controller adjust a clutch actuator position is response to movement of a clutch pedal. During an engagement or a disengagement, the controller monitors sensor signals to determine the actuator position corresponding to the touch point. The sensors may directly indicate clutch torque or may respond indirectly. A Giant Magneto Resistive (GMR) sensor provides a precise shaft rotational position signal which can be twice numerically differentiated to yield an accurate and stable acceleration signal. The controller updates the touch point based on a change in the sensed acceleration or torque. The controller then adjusts the relationship of actuator pedal position to clutch pedal position, making mechanical wear adjustment unnecessary. | 5 |
This is a continuation of co-pending application Ser. No. 344,672 filed on Apr. 28, 1989, now abandoned.
FIELD OF THE INVENTION
This invention relates generally to oil-in-water emulsion metal working baths and in particular to additives for conditioning and maintaining such baths. Specifically, the present invention relates to conditioning additives including therein amine complexes of copper and molybdenum, useful for conditioning metal working baths.
BACKGROUND OF THE INVENTION
The metal working industry utilizes large amounts of oils to assist in the forming of metal parts. Such oils are generally utilized in the form of what is referred to as soluble or emulsifiable oils, employed in the form of oil-in-water emulsions. These emulsions typically contain 80-99% water and are employed as cutting fluids, coolants and lubricants in machining, grinding, drilling, pressing or other metal working applications. The oil used is usually napthenic base, low to medium viscosity and generally includes approximately 10-30% of emulsifiers, rust inhibitors and various other ancillary ingredients. These oils and emulsions are well-known to those of skill in the art and need not be elaborated upon in any greater detail herein.
In most large-scale metal working operations, metal working fluids are collected and recycled, typically in large tanks or pits. Debris is filtered or skimmed therefrom, other impurities removed and the fluids are returned to service. Problems occur owing to various chemical changes in metal working fluids, which changes detrimentally affect the function of the fluids.
The oil-in-water emulsion can provide an ideal growth medium for bacteria, algae or other microbes and such biological contamination is one major source of metal working bath contamination. Biological contamination can result in loss of lubricating power, breaking of the emulsion and separation of the bath into aqueous and oily components. Microbial contamination can also cause the generation of noxious odors and decomposition of the components of the bath. Contamination can result in a cycle of bath degradation; bacteria attack the emulsifiers degrading bath lubricity and breaking the emulsion; furthermore, bacterial growth generates hydrogen sulfide or other sulfur bearing compounds which corrode metal parts, provide a health hazard and serve to reduce the pH of the metal working bath. The reduced pH in turn causes further emulsion breakdown and the sulfides can nourish the growth of algae further degrading bath performance. Such contamination can result in a runaway cycle which can damage expensive equipment and which inevitably necessitates costly disposal of contaminated baths. The addition of strong bases to contaminated baths only temporarily raises the pH. The contaminating organisms quickly generate more acidic sulfide compounds further degrading the bath.
In many instances, sulfur or sulfur containing additives are added to the cutting oils to improve lubricity, machinability and subsequent finish of processed articles. The addition of free sulfur causes the formation of sulfides at a very speedy rate and these types of cutting oils have a historically short life span. Use of the additive of the present invention greatly retards sulfide formation and greatly extends the life of the bath.
Many attempts have heretofore been made to control the growth of organisms in metal working baths. For example, U.S. Pat. No. 3,244,630 discloses the introduction of iodine vapor into a metal working bath for control of micro organisms. Iodine is toxic, hard to handle and corrosive to a variety of metals. Furthermore, iodine can chemically react with and degrade bath components. Consequently, this method has not found widespread acceptance.
U.S. Pat. No. 3,365,397 discloses another prior art approach to microbial contamination of metal working baths which relies upon the use of phenol as a bactericide. Phenol is a toxic compound and furthermore is of limited bactericidal use, since there are a variety of micro organisms which can metabolize phenol.
U.S. Pat. No. 3,240,701 discloses the use of aminoacetic acid compounds such as diethylenatriamine pentaacetic and 1, 2-diaminocyclohexamine tetraacetic acid chelates of metal ions. These compounds are utilized to inhibit the growth of bacteria; however, they have the undesirable property of reacting with zinc which is often present in the metal working baths. This is a significant problem since lubricating oils are frequently enhanced with zinc containing additives such as zinc dialkyldithiophosphate (ZDTP). Such ZDTP additives enhance the lubricity and antiwear properties of the oil. Zinc containing lubricating oils frequently leak into cutting oil baths. Presence of zinc chelating compounds is obviously undesirable in stabilizers or additives, for metal working fluids.
U.S. Pat. No. 4,129,509 discloses the use of complexes of copper ion with polyhydroxy compounds such as citric acid, for purposes of inhibiting microbes. As is set forth in the specification thereof, these complexes exhibit a sigmoidal decomposition over a varying pH range wherein the decomposition of the complex, and subsequent release of metal, increases very sharply over a given portion of the pH range. The complexes of the '509 patent also suffer from the shortcomings of complexing zinc and are therefore limited in utility.
From the foregoing it should be clear that there is a need for a metal working fluid additive which functions to inhibit the growth of undesirable microbes in an oil-in-water bath. It is further desirable that any such compound be of low toxicity, easy to handle, non-corrosive to metals and non-chelating of zinc. In general, the additives of the present invention include complexes formed from the reaction of copper salts with alkanolamines as well as the reaction product of molybdenum salts with alkanolamines. Such compounds exhibit high levels of microbial inhibition and furthermore are non-corrosive, easy to handle and of low toxicity. Most importantly, the copper and molybdenum containing complexes of the present invention do not chelate zinc. This selective chelating ability makes the present invention very useful with all currently employed metal working fluids.
The use of alkanolamine complexes of copper for the control of algae in streams and other bodies of water is shown in U.S. Pat. No. 2,734,028; however, there is no teaching whatsoever in that patent of the use of such compounds in conjunction with metal working fluids, nor is there any teaching or suggestion of the use of molybdenum complexes for any purpose whatsoever.
The present invention fulfills a long-felt need for a low-cost, safe, non-corrosive and simple to use conditioning additive which is compatible with a wide variety of metal working baths, particularly zinc contaminated baths. These and other advantages of the present invention will be presently apparent from the discussion, examples and claims which follow hereinbelow.
SUMMARY OF THE INVENTION
There is disclosed herein a zinc contamination tolerant additive for an oil-in-water emulsion metal working bath which additive comprises an aqueous solution of the reaction product of a salt of copper and an alkanolamine as well as the reaction product of a salt of molybdenum and an alkanolamine. In one embodiment, the reaction product of the salt of copper and the alkanolamine is the reaction product of at least two moles of alkanolamine and one mole of copper salt; similarly, the molybdenum containing reaction product may be the reaction product of at least two moles of alkanolamine and one mole of the salt of molybdenum.
The molybdenum salt may be a salt of molybdic acid such as ammonium molybdate. The salt of copper may be selected from the group consisting essentially of copper sulfate, copper nitrate, copper chloride, and copper acetate. And the alkanolamine may be selected from the group consisting essentially of ethanolamine, diethanolamine, triethanolamine and combinations thereof.
The additive may further include potassium borate and/or potassium hydroxide and/or wetting agents and/or surfactants.
The copper containing compound may be present in approximately 5-15 weight percent and the molybdenum containing compounds may be present in approximately 0.1-1% weight concentration. The additive may include other ingredients such as phosphate esters, pyrophosphates and the like.
The present invention also includes a method of conditioning an oil-in-water emulsion metal working bath comprising the steps of adding to the bath 10-100 parts per million of copper in the form of a reaction product of a salt of copper and an alkanolamine and 1-10 parts per million of molybdenum in the form of the reaction product of the salt of molybdenum and an alkanolamine. In one preferred embodiment, the method comprises adding approximately 40-60 parts per million of copper and 4-6 parts per million of molybdenum to the bath. The method may also include the further step of maintaining the pH of the bath at a value of greater than 8.5 and toward this end can include the step of adding a pH stabilizer to the bath. The method may include the further steps of adding at least 0.01 weight percent of a wetting agent to the bath and at least 0.05 weight percent of a nonionic surfactant to the bath.
DETAILED DESCRIPTION OF THE INVENTION
The present invention concerns zinc compatible additives for oil-in-water type emulsion metal working baths. The additives inhibit microbial growth in the baths and include a source of copper in the form of a copper-amine complex, most preferably a complex of a copper salt and an alkanolamine. Compounds of this type are stable, easy to handle and have good solubility properties in the oil-in-water emulsions.
One particularly preferred copper complex is the complex of a copper containing salt such as copper sulfate, copper nitrate, copper chloride, copper acetate and the like together with an alkanolamine such as mono, di or tri ethanolamine. Similarly, other alkanolamines such as propanolamines and the like may be similarly employed. Also, nonhydroxyl alkyl and aryl amine compounds may in some instances have similar utilities.
It is most preferred to employ a complex of copper sulfate and triethanolamine generally in the ratio of approximately two moles of amine to one mole of copper salt. Although the copper compound may be utilized by itself, it has been found that adding a molybdenum-amine complex together with the copper complex increases the rustiinhibition properties of the metal working bath, particularly on freshly ground metal shavings. The molybdenum amine complexes are generally similar to the copper complexes in terms of amine components and molar proportions. There are a variety of water soluble molybdenum salts which may be employed; however, for reasons of convenience it has been found most advantageous to employ salts of molybdic acid. Ammonium molybdate is one such salt readily available and as will be described hereinbelow may be readily complexed with the amines.
Preparation of the Copper Complex
The copper complex may be prepared from a variety of materials as set forth hereinabove, and under a variety of conditions which will be obvious to one of skill in the art. One method for preparation of the complex proceeded as follows:
360 pounds of 85% purity commercial grade triethanolamine was dissolved in 390 pounds of water maintained at 160° F. in tank No. 1. In tank No. 2, 250 pounds of copper sulfate --5 H 2 O (98.6% purity) was dissolved in 337 pounds of water at 160° F. Over a period of about 30 minutes, the copper sulfate solution was introduced into the triethanolamine solution with stirring. The temperature was maintained at 160° F. After all the copper sulfate had been added, stirring was continued for an additional 30 minutes when 45 pounds of diethanolamine was added. After an additional 60 minutes of mixing, the batch was weighed and assayed. The total yield was 1,382 pounds of solution having a copper content of 4.52%. The triethanolamine-copper ratio was approximately 2-1 mole with a very slight excess of triethanolamine. The pH of the resultant solution was 9.84 and presented a stable form of triethanolamine-copper complex stabilized with diethanolamine.
The copper complex thus prepared is capable of releasing copper into solution and the amount of released copper is found to increase relatively monotonically with increasing pH. This is in contrast to behavior of copper-polyhydroxyacid compounds such as those of the U.S. Pat. No.4,129,509 which exhibit a sigmoidal pH dependent decomposition.
Tests of the foregoing copper compound was carried out on emulsions comprised of 5% commercial grade soluble oil in 95% water. Six emulsions were prepared; three were used as a control and to the other three the equivalent of 10, 20 and 30 milligrams/liter of copper (as Cu) was added in the form of the foregoing solution. The solutions were automatically mixed for 120 seconds every hour. The initial pH of all six solutions was 9.12, however, after three days the untreated solutions began to develop odor and a corresponding decrease in pH. The bacteria count in the untreated solutions after six days was measured at 10 7 using Ames Biostixreagent strips, and the pH of these samples dropped to 8.24. The copper treated solutions in contrast showed no odor, no bacteria count and the pH was 8.78.
In practical tests carried out in actual fluids employed in conjunction with the machining of cast iron it was found that at little as 10 PPM copper introduced in the form of a copper-amine complex prevented the usual bacterial growth and sulfide formation. It has further been found that when amounts of copper in excess of 30 PPM (preferably between 40-60 PPM) were employed the emulsion stability greatly increased. The oil droplets were smaller than in untreated baths and the soluble oil was found to form a more perfect film on the freshly machined metal and the ground chips. It was further found that the copper amine complex, or at least the copper portion of the complex dissolves into, or becomes part of the oil portion of the emulsion. Analytical tests involving measurement of the partition of the copper between the oil and water component of the bath confirms that at least 80% of the copper resides in the oil and stabilizes the emulsion.
The Molybdenum-Amine Complex
The molybdenum-amine complex may be prepared from the various materials described hereinabove and methods for its preparation will be obvious to one of skill in the chemical art. However, one particularly useful complex was prepared as follows:
350 pounds of triethanolamine (85% pure commercial grade) and 220 pounds of water were charged into a tank and heated to 160° F. In a second tank 205 pounds of ammonium molybdate (85% molybdic acid having a theoretical formula of: (NH 4 ) 2 Mo 2 O 7 )) was dissolved in 300 pounds of water maintained at 160° F. The ammonium molybdate solution was slowly introduced into the triethanolamine solution. The temperature was maintained at 160° F., the solution agitated for an hour, then weighed and assayed and found to contain 9.06% Mo.
It has been found that metal working solutions containing both the copper and molybdenum additives showed marked improvement in rust prevention capability as compared to untreated solutions. Cast iron shavings covered with a soluble oil emulsion generally rusted within 24 hours while an emulsion including 40-60 parts per million of copper and 4-6 parts per million of molybdenum in the form of the amine complexes extended the rust free period for over seven days.
Even though the hereinabove described copper-molybdenum amine complex additive suppressed microbial growth, eliminated odor formations, prevented rust and stabilized the emulsions it was still found that some lowering of the pH of the metal working bath occurred, albeit at a lower rate. It has further been found that addition of a suitable buffer together with the Cu--Mo complex helps to stabilize the pH and the resultant additive eliminated most of the common problems associated with these baths.
There are a wide variety of buffering agents available and usable with the present invention including sodium tetraborate (Borax) and potassium borate. Potassium borate has been found to be particularly advantageous as a pH stabilizer since it is of high solubility and is chemically compatible with the Cu--Mo amine complex. It has further been found that addition of relatively small amounts of potassium hydroxide imparts an optimum pH to the metal working bath and acts to prevent crystalization of the potassium borate. In general, it has been found that a metal working fluid bath conditioner can be made from an aqueous solution of approximately 5-15 weight percent of the copper amine complex, approximately 0.1-1 weight percent of the molybdenum amine complex, approximately 5-15 weight percent of potassium borate and approximately 0.1-1 weight percent of potassium hydroxide. This composition provides a conditioner which is added to the soluble oil bath in approximately 1% volume.
A particular additive composition was prepared as follows, with all percents being given by weight:
______________________________________Water 79.0%Potassium Borate 10.0%Cu-Amine Complex 10.0%Mo-Amine Complex 0.5%Potassium Hydroxide 0.5%______________________________________
Addition of 1% of the conditioner to the soluble oil bath produced measured levels of approximately 0.1% potassium borate, approximate 50 PPM copper and 5 PPM molybdenum. The pH of the bath was 9.3 and after five days (80 working hours) the pH had dropped to only 9.1. It was found that this bath remained stable and needed only periodic additions of the conditioner complex when further oil and water was added to the bath.
An additional advantage of the abovereferenced composition is that a further increased rust inhibition is still further increased. In a test, cast iron shavings were placed in a Petri dish approximately one-half inch deep and covered with a soluble oil emulsion right after machining. These chips were rusted over 50% before 48 hours. When the experiment was repeated utilizing a soluble oil emulsion including only the Cu--Mo amine additive it was found that practically no rust appeared for eight days after which time the chips slowly picked up oxide. When the experiment was repeated again utilizing a soluble oil emulsion including 1% of the foregoing composition it was found that the chips did not rust for 25 days and even after that, the rust appeared very slowly when the chips were exposed to air at room temperature.
It has further been found that the addition of surfactants and/or wetting agents to the aforementioned compositions further increases their efficiency by facilitating wetting of chips and fragments of metal. Nonionic surfactants for example, are useful additions to the aforementioned additives. Among said surfactants are alkylphenol-ethylene oxide adducts as well as primary or secondary alcohol ethoxylates. One particularly preferred surfactant is an alkylphenol ethylene oxide adduct wherein the alkyl chain is between 8 and 13 carbons long and the adduct includes 7-12 moles of ethylene oxide.
Additions of wetting agents still further increase the performance of the bath additive. There are available to those of skill in the art a great variety of wetting agents and it has been found that wetting agents characterized as having a fast skein wetting time of less than 30 seconds at a concentration of 0.1% or lower, when tested according to the DravesClarkson method are particularly preferred. One wetting agent meeting this standard is the sodium salt of dioctyl sulfosuccinate. This material has a Draves sinking time of six seconds at a 0.25% concentration.
In general, it has been found that a minimum of 0.5% of the nonionic surfactant and 0.01% of the wetting agent are necessary in order to confer desirable properties upon the metal working fluid bath.
A particular additive composition included the following weight percentages of reagents:
______________________________________Water 73.0%Potassium Borate 10.0%Cu-Amine Complex 10.0%Mo-Amine Complex 0.5%Nonionic Surfactant 5.0%Sodium Dioctyl 1.0%Sulfosuccinate______________________________________
The nonionic surfactant was a product sold under the trade name Igepal CO 630 by the GAF Corporation and may be generally characterized as an alkylphenol ethylene oxide adduct.
As in the foregoing example, 1.0% of the additive preparation was added to a soluble oil both containing 4.5% of soluble oil. Wetting ability of the resultant treated bath was assessed by pouring 25 milliliters of the bath into a Petri dish having 200 grams of freshly ground cast iron chips arranged in a mound therein with a 4-5 inch base diameter and a quarter inch top diameter. It was shown that all of the treated oil was absorbed onto the surface of the chips within 120 seconds. When the experiment was repeated utilizing a similar composition lacking the surfactant and wetting agent, it was found to take 15-30 minutes for the oil to be completely absorbed onto the chips.
The chips thus treated were dried and stored exposed to air. There was no visible rust on the chips for 60 days. When a similar body of chips were treated with a soluble oil emulsion not having the aforementioned additives it was found that rust appeared within 48 hours and covered over 50% of the surface of the chips.
Further materials may be utilized in the additives to confer additional properties to the metal working bath. For example, it has been found that addition of a water soluble phosphate ester still further increased the lubricity of the oil. It has been found that any one of a member of the series of alkyl and alkylaryl (ethylenoxy) phosphate esters may be so employed. In general, such materials may be characterized as partial phosphate esters of an ethylene oxide adduct of a hydrophobic carbon chain. Typical of these materials is a product sold by the GAF Corporation under the name Antara LP 700; one of skill in the art could obviously select an equivalent material from the many commercially available.
In those instances where grinding and machining of aluminum, copper and other non-ferrous materials is carried out, it has been found that various additives further increase baths, performance. For example, it has been found that addition of a pyrophosphate compound improves the appearance of aluminum, copper and alloys made of these materials. Furthermore, an addition of the sodium salt of 2-mercapto benzothiazole, manufactured and sold by the RT Vanderbilt Company left the freshly processed metal surfaces passive to oxidation. In general, it has been found that an additive composition including approximately 1-10% of the phosphate ester, 1-10% of the pyrophosphate and approximately 0.5-5% of the 2-mercapto bienzothiazole salt gave an additive which greatly enhanced the stability and properties of metal working baths used in conjunction with non-ferrous metals.
A particular composition in accord with these principles was prepared including weight percents of the following:
______________________________________Water 63.0%Potassium Borate 10.0%Cu-Amine Complex 10.0%Mo-Amine Complex 0.5%Potassium Hydroxide 0.5%Nonionic Surfactant 5.0%Na-Dioctyl 1.0%SulfosuccinateAntara LP 700 4.0%2-Mercapto 2.0%Benzothiazole-NaTetrapotassium 4.0%Pyrophosphate______________________________________
This additive, when added to a metal working soluble oil emulsion in approximately 1% concentration conditions the bath so as to eliminate odor, reduce bacterial growth, stabilize the emulsion, improve lubricity, inhibit corrosion, and stabilize pH fluctuation thereby improving the performance of life of the bath, as well as preserving the freshly ground chips from oxidation and improving the machining of all non-ferrous metals. This particular composition may be utilized in combination with a variety of metal working baths and because of the selective chelating ability of the organic materials utilized in the metal-amine complexes, does not interfere with zinc additives in the metal working baths.
While the aforegoing additive compositions have been described in terms of aqueous solutions added to metal working baths at approximately 1% concentration, it will of course be appreciated that such additive compositions may be made more or less concentrated and accordingly added to metal working baths in greater or lesser amounts. For this reason, the various proportions given herein are to be considered relative and merely representative of rough amounts of the components. In general, it has been found that a metal working bath should be conditioned by the inclusion of between 10-100 parts per million and more preferably 40-60 parts per million of copper in the form of the Cu-amine complex of the present invention. The bath should further include approximately 1-10 parts per million, and preferably 0.1-1 part per million of the Mo-amine complex. The pH of the bath should be maintained at values equal to or greater than 8.5 and toward that end it is preferable that the bath include at least 0.1% of a pH stabilizing material such as potassium borate and optionally about 0.1% by weight of potassium hydroxide. As mentioned hereinabove, the bath may also include 0.01% by weight of a wetting agent and 0.05% by weight of a nonionic surfactant.
It has been found advantageous in many instances to include an emulsifier in the additive, particularly when further replenishment of the oil component of the bath is anticipated, or when accumulations of tramp oil build up in the bath necessitating emulsification thereof.
There are a great many emulsifiers available for use in oil-in-water emulsions of the types discussed herein, and one of skill in the art could readily select an emulsifier for inclusion in the additive of the present invention. One particular group of emulsifiers having significant utility are the alkylphenols, typified by ethyoxylated nonylphenol. Such materials are available from a variety of suppliers including the Steppen Chemical Company which sells an ethyoxylated nonylphenol emulsifier under the tradename Makon.
It has been found that emulsifiers of this type, typically, in amounts of 1-4 parts per thousand can disperse up to ten times their volume in oil.
In light of the foregoing, it will be apparent that many variations of the foregoing compositions may be employed to condition metal working baths in keeping with the basic principle of the present invention; namely, that Cu-amine complexes are advantageously employed to limit microbial growth in metal working baths of the oil-in-water emulsion type. The foregoing discussions and examples are merely meant to be illustrative of the general principles of the present invention and not to be limitations upon the practice thereof., It is the following claims, including all equivalents, which define the scope of the invention. | A conditioning additive for an oil-in-water emulsion metal working bath includes a copper-amine complex and may further include a molybdenum-amine complex. The complexes may comprise the reaction product of alkanolamines and salts of the metals. The additive may further include pH stabilizing agents, wetting agents, corrosion inhibitors, emulsifiers and surfactants. The additive inhibits microbial growth, stabilizes the emulsion, improves lubricity, prevents corrosion and improves the finish of parts produced therewith. | 2 |
FIELD OF THE INVENTION
The invention relates to a method for increasing the strength of a paper or paperboard product and to a paper or paperboard product having increased strength.
BACKGROUND OF THE INVENTION
Paper and paperboard products (referred to hereinafter as "paper" for purposes of simplicity) made from cellulosic materials owe their strength, in part, to inter-fiber hydrogen bonds which form when water is drained from an aqueous slurry of fibers on a paper machine producing a web of fibers which is then pressed and is dried. Because the hydrogen bonds between fibers are relatively weak, the bonds are easily broken by the addition of water to paper which makes paper ideally suited for recycle.
Unfortunately, paper made using cellulosic fibers obtained from recycle or waste paper sources does not exhibit the same degree of strength as paper made from virgin pulp. Each time wood fibers are recycled, some of the bonding strength inherent in the fibers is lost. Loss in bonding strength may be due to structural damage to the fibers caused by repeated refining or other mechanical stress and/or due to a change in crystal structure of the cellulose in the fibers as a result of treatment with various agents and/or heating the pulp or paper. The change in crystal structure of the fibers is evidenced by the decreased ability of recycled fibers to swell.
Cellulosic fibers made directly from wood sources may also exhibit relatively weak strength properties due to the paper manufacturing methods or properties of the pulp. In order to increase the bonding strength of cellulosic fibers, particularly recycled cellulosic fibers, dry strength agents such as cationic starches have been added to the fibers. However, there is a pronounced decrease in retention of many dry strength agents on the fibers during paper formation when more than about 1 wt.% of the agent is applied, which limits the level of improvement achievable using such additives.
Cellulosic fibers have been chemically modified by treatment with alphachloroacetic acid or succinic anhydride dissolved in a solvent in an attempt to increase the bonding of cationic dry strength agents to the fibers so that more is retained in the web forming on the machine. However, chemical modification by such techniques tends to reduce the dimensional stability of the fibers. Because of the loss of dimensional stability, the fibers exhibit greater swellability resulting in paper products which change their dimensions more dramatically with changes in moisture and/or temperature.
It is therefore an object of the invention to provide a method for upgrading the quality of paper containing secondary fibers.
Another object of the invention is to provide a method for increasing the strength of paper products.
Still another object of the invention is to increase the interchain hydrogen bonding characteristics of cellulosic fibers formed into a paper web from wood pulp without adversely affecting the swellability of the fibers.
Another object of the invention is to provide high strength paper products made from recycled cellulosic fibers.
Yet another object of the invention is to provide a method for producing high strength pulp for paper products which is substantially independent of the source of the pulp fibers.
Still another object of the invention is to provide a method for increasing the ability of cellulosic fibers to bond to dry strength agents or wet strength agents.
SUMMARY OF THE INVENTION
With regard to the foregoing and other objects and advantages, the present invention provides a method for increasing the bonding strength of cellulosic fibers. The method comprises contacting an agent, in particulate or vapor form, comprising a carboxylic acid cyclic anhydride with relatively dry cellulosic fibers and heating the fibers and agent in contact therewith at a temperature and for a time sufficient to substantially increase the potential of the fibers to form strong interfiber bonds when the fibers are later used for making paper or paperboard products.
In another aspect, the invention provides a method for increasing the strength of a paper or paperboard web containing cellulosic fibers which comprises applying to the fibers of a web having a moisture content below about 20 % by weight an agent,in particulate or vapor form, comprising a carboxylic acid cyclic anhydride and thereafter heating the web at a temperature and for a time sufficient to substantially increase the bonding strength of the web fibers.
In accordance with yet another aspect of the invention, a method is provided for treating cellulosic fibers which comprises contacting relatively dry cellulosic fibers with particulate maleic anhydride and heating the fibers at a temperature sufficient to significantly increase the carboxyl content of the fibers without significantly embrittling the fibers. The fibers may be in the form of pulp or they may be fully or partly consolidated in a web or sheet.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects and advantages of the invention will now be further described in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic diagram of a method for increasing the bonding strength of pulp in a secondary fiber pulping process;
FIG. 2 is a schematic diagram of a method for increasing the bonding strength of pulp in a fluff pulp drying process;
FIG. 3 is a schematic diagram of a method for increasing the bonding strength of pulp in a dry-lap pulp production process; and
FIGS. 4, 5 and 6 are graphical representations of effects a strength agent has on the carboxyl content and surface charge of pulp at various curing temperatures.
DETAILED DESCRIPTION OF THE INVENTION
The invention provides a method for increasing the bonding strength of cellulosic fibers, especially fibers from recycled paper, above the strength which may be obtained by internal chemical modification or cross-linking of the cellulose in the fibers and without the drawbacks associated with prior methods. According to the method, relatively dry wood pulp fibers are treated with an agent in particulate form comprising a carboxylic acid cyclic anhydride and heat is applied to the treated fibers or web to effect a reaction between the agent and the fibers or web. The wood pulp fibers to be treated may be loose or unconsolidated or they may be incorporated in a web of cellulosic fibers. By "relatively dry" it is meant that the fibers or a web containing the fibers do not contain sufficient moisture to permit significant hydrolysis of the agent applied to the fibers prior to application of sufficient heat to effect a reaction between the agent and the fibers. Typically, a moisture content below about 20% by weight water will be sufficient to limit hydrolysis of the agent before it is able to react with the fiber surface.
While not desiring to be bound by theoretical considerations, it is believed that increasing the carboxyl content of the cellulosic fibers by surface modification of the fibers rather than by cross-linking the cellulose internal to the fibers results in a significant improvement in the bonding ability of the fibers and an increase in the ability of the fibers to adsorb and/or interact positively with dry-strength or wet strength agents. Accordingly, more dry and wet strength additives which have a net cationic charge may be retained in the pulp than with fibers which have not been treated according to the process of the invention, resulting in even greater strengthening effects.
Cellulosic fibers used in the methods and products of the invention may be obtained from a number of sources. Virgin pulp is provided from wood chips which are converted to fibers by cooking according to well-known processes and dispersed in water to make pulp which becomes the furnish for papermaking. Virgin pulp includes wet-lap pulp, fluff-pulp and bale pulp. Wet-lap pulp is made by draining and squeezing water from a fiber slurry without using heat to dry the pulp. Both fluff-pulp and bale pulp are dried in the presence of heat from sources such as hot air, infra-red heating devices and hot metal surfaces on drier cans. Regardless of the source of the pulp, the pulp may be used in its bleached or unbleached form to make a paper or paperboard product having increased bonding strength.
The pulp may also be obtained from recycle paper sources. Because the pulp from recycle sources has been previously refined, treated and heated, the bonding strength of fibers in such pulp is generally less than in virgin pulp.
Recycle pulp is typically received in the form of bales or loose sheets. The moisture content of the pulp is usually in the range of from about 4 to about 20 percent based on the oven dry weight of solids in the pulp. The pulp may be treated in accordance with the invention as received, but it is preferred that the pulp be shredded and/or hammer milled before treatment by the methods according to the invention in order to increase the surface area of the pulp accessible to the powdered reagent or its vapors.
Virgin pulp and recycle pulp may be used alone or mixed together to provide a variety of paper products so as to meet certain property, economic or business objectives. Regardless of the source of the pulp and how it has been prepared, methods conducted according to the invention generally provide significant improvement in the bonding strength potential of the fibers, especially with regard to retention of dry and wet-strength agents. The method is particularly applicable to cellulosic pulp or a cellulosic fiber web which is heated to dryness on a papermaking machine after treating the pulp or web with the agent.
In the treatment process according to the invention, virgin pulp, recycle pulp, a mixture of virgin and recycle pulp or a web made from virgin pulp, recycle pulp or a mixture of virgin and recycle pulp is treated with the agent in particulate form such as a dry powder, as a molten liquid which is sprayed onto the fibers or web, as a vapor associated with heating particulates or droplets of the agent within the fiber mixture or before addition of the agent to the fiber mixture, or as a dissolved component of a non-hydrolyzing volatile solvent solution. The solvent is evaporated prior to or during the heating step leaving the agent in contact with the fibers. While not preferred, the agent may also be applied to the pulp or web directly as a vapor. Regardless of the method used to treat the pulp and/or web with the agent, an important aspect of the invention is that the agent be delivered to the relatively dry pulp or web in a dry and/or substantially unhydrolyzed form. The agent may also be applied to the pulp and/or web by dispersing the agent in a substantially non-hydrolyzing medium.
Preferably, the agent used to treat the pulp or web comprises a cyclic anhydride of the type obtained when water is removed from a di-functional or multi-functional carboxylic acid. A preferred cyclic anhydride is a dicarboxylic acid anhydride having a melting point below about 150° C. and a vapor pressure within the range of from about 2 Torrs to about 170 Torrs, including all ranges subsumed therein. Of the foregoing, the agent is more preferably maleic anhydride, phthalic anhydride, succinic anhydride and mixtures of two or more of these compounds, and is most preferably maleic anhydride.
The agent may be mixed with relatively dry pulp or applied to a relatively dry web as a powder, spray or vapor. Preferably, the moisture content of the pulp or web is less than about 20 percent based on the dry weight of the fibers or web. Accordingly, it is preferred that a significant amount of water be removed from the pulp or web or that relatively little or no water be added to an already dry pulp or web before treatment, thereby reducing the tendency of the agent to react with water rather than the hydroxyl groups present at the surfaces of the fibers.
It is also preferred that the agent be applied to the pulp or web in particulate form in the absence of a solvent or carrier fluid which will hydrolyze the agent to any significant extent before it is able to interact with the fiber surface. As a particulate, the agent may be applied to the fibers or fibrous web by techniques well known to those of ordinary skill.
Equipment which may be used to apply the powder, molten liquid, or vaporized agent to the fibers or web includes conventional grinding and pulverizing equipment such as hammer mills, impactors, rolling-compression mills, attrition mills, tumbling mills, fluid-energy mills, or agitated mills. The process may use direct or indirect heating with transport of individualized fibers, shredded paper, or sheet materials through the heated zone within a pipe by means of a conveyor belt, screw, or pneumatic conveyor.
In a preferred embodiment, solid maleic anhydride is introduced in chunk or pellet form into the hopper of a pendulum mill, a type of roller mill commercially available from Bradley Pulverizer Company of Allentown, Pa.. The roller mill reduces the particle size of the maleic anhydride to below 75 μm diameter and feeds the ground particles by gravity into a screw conveyor. Bales of virgin or secondary fiber are separately fed into the hopper of a shredder, yielding a loose, porous collection of paper strips. Powdered agent is conveyed with the fiber by means of a high-amplitude screw conveyor which provides substantially homogenous mixing of the components in the screw conduit with minimum physical damage to the fibers.
It is preferred that the initial mixing of fiber and agent take place under ambient temperature conditions and that the contents of the conduit be conveyed through a preheating zone and then through a curing zone having a temperature controlled in the range of from about 80° to about 110° C. The temperature of the curing zone may be controlled by adjusting the amount of low-pressure steam within a jacketed preheater zone of the conduit reactor. The length of the curing zone section of the conduit is selected to provide a suitable curing time at a desired production rate of treated fibers. For example, for a production rate of 10 pounds per day treated fiber having a fiber packing density of 6 pounds per square foot, and using a pipe reactor having an effective diameter of 18 inches, a reaction zone 13 feet in length will provide a curing time of approximately ten minutes.
The curing zone is preferably followed by a quenching zone in which the maleic anhydride treated fiber is cooled by a spray of water or mildly alkaline solution which serves to quench any unreacted anhydride and convert the anhydride to acid or acid-salt byproducts. The reactor is designed such that excess water will tend to flow by gravity toward an exit end of the reactor. Accordingly, the entire reactor may be inclined downwards toward the exit end thereof.
The agent is most preferably provided in finely divided powder form having a mesh size of from about 20 to about 200 mesh. Preferably, the agent is applied in an amount sufficient to provide from about 0.01 to about 10 percent by weight agent based on the oven-dried weight of the pulp, and most preferably from about 0.01 to about 2.0 percent by weight.
It is preferred to treat pulp with the agent before the dry fibers are wetted and before any significant heat is applied to the fibers. Dry fibers are preferably obtained from bales of recycled paper. Accordingly, the agent may be added to relatively dry pulp in a shredding, fluffing or hammer-milling operation. In the alternative, the agent may be added to a relatively dry web of fibers after the wet end of a paper machine after the moisture content of the pulp has been reduced to less than about 20% by weight, to relatively dry pulp after the wet end of a dry-lap pulp forming machine, to a relatively dry web of paper or paperboard or to a relatively dry pulp in a flash-drying process.
After applying the agent to the pulp, the mixture of fiber and pulp is heated to a temperature and for a time sufficient to bring about a reaction between the agent and the pulp. Generally, the temperature may range from about 50° to about 120° C. At lower temperatures, the heating time used may be longer than at higher temperatures. However, relatively long heating times and temperatures higher than about 120° C. should be avoided as they may cause embrittlement of the fibers due to internal cross-linking of the cellulose within the fibers. Accordingly, heating times may range from about 5 minutes to about 15 minutes at temperatures ranging from about 50° and about 100° C. and from about 1 to about 5 minutes at temperatures ranging from about 110° to about 120° C. It is preferred to rinse the pulp after the treatment with water having a pH above about 4 in order to convert any residual anhydride to its acid or salt form.
Various dry and wet strength agents may be used in conjunction with the agent to further increase the strength of paper made from the treated pulp. These include, but are not limited to, cationic starch, copolymers or acrylamide, polyamide resins, polyamidoamine-epichlorohydrin resins, cationic guar products and mixtures of like materials with anionic polymers. A particularly preferred agent is a cationic starch solution. The amount of dry-strength or wet-strength agent used may range from 0 to about 40 pounds per ton of dry paper product, or more preferably from about 2 to about 10 pounds per ton of dry paper product. It has been found that pulp treated according to the process of the invention exhibits a surprising increase in the retention of wet- or dry-strength agents as compared to pulp not treated with the agent according to the methods of the invention.
Suitable retention aid polymers, microparticles and other chemical additives conventionally used for preparing paper products may also be used to increase the efficiency of retention of the agent on the mat of fibers during the paper web forming process. For example, calcium carbonate or other buffers may be mixed with the agent to promote its reactivity during the heating step of the process. Likewise, the agent may be diluted with a filler material such as clay, talc, starch or cellulose to help disperse the agent throughout the fibers to be treated.
The agent may be mixed with dry pulp in shredded or fluffed form in hammer mill or shredder or on a conveyor belt passing through a heated zone prior to slurrying the pulp. After the heated zone, a water shower may be used to hydrolyze any unreacted agent. Cellulosic fibers and the agent may also be combined and mixed in a fluidized bed or the fibers may be treated with the agent during drying of the fluff pulp or dry-lap pulp after the pulp has attained a moisture content of less than about 20% by weight.
Various operational aspects of the invention will now be discussed with reference to the drawings. FIG. 1 illustrates one embodiment of a method for treating relatively dry secondary or recycle fibers to increase the strength thereof wherein dry-bale pulp 2 is transported to a first conveyer 4 by a suitable transportation device 6. The conveyor transfers the pulp to a hammer mill 8 to further individualize the fibers before treatment.
Powdered agent 10 comprising a carboxylic acid anhydride from a source 12 is added with the dry-bale pulp on the conveyor 4 to the hammer mill 8 for treatment. The agent may be added by dusting it onto the pulp or by spraying it on in molten form or applying the agent to the pulp as a vapor or as a mixture with a substantially non-hydrolyzing medium or diluent such as clay, talc or the like.
The milled pulp/agent mixture 14 from hammer mill 8 is fed to a second conveyor 16 which transports the mixture 14 through a heater unit 18 for heating the mixture 14 to effect reaction between the pulp and the agent. In addition to or in lieu of mixing the agent with the pulp in the hammer mill 8, the agent 10 may be added to the pulp near the entrance 20 of heater unit 16. A quench spray 22 containing water or a dilute alkaline solution may be applied to the mixture 14 adjacent the exit 24 of the heater in order to cool the pulp and hydrolyze any excess agent. The treated pulp 26 may be conducted from unit 16 to a hydrapulper 28 for further processing according to conventional papermaking techniques.
FIG. 2 illustrates an embodiment of a treatment method according to the invention for increasing the strength of fluff pulp. Pulp in the form of an aqueous slurry is supplied via conduit 30 to a vacuum filter unit 32 for removal of water. The discharge filter cake 34 from the vacuum filter is then transported via screw conveyor 36 to a cage mill dryer 38 wherein it is contacted with a flow of hot gas 40 to heat, dry the pulp. As the filter cake 34 is contacted in the cage mill dryer 38, dust and fine fiber particles are formed. The hot gas used to dry the pulp in conveyor 36 enters the system through a dust chamber 44 which entrains and removes the fine particles from the dry pulp before discharging the pulp 46 from the system. The fine particles are entrained in the hot gas and transported with the hot gas through dryer 38 and out of dryer 38 to cyclone separator 42.
The dust and fine particles generated by dryer 38 are collected in cyclone separator 42 for recycle to the pulp. In the cyclone separator, relatively particulate free gas is conducted by conduit 48 to a gas scrubber 50 to remove any particles too fine to be removed in the cyclone separator before the gas is discharged to the atmosphere through exhaust port 52 of the scrubber 50. The larger particles separated from the gas stream by cyclone separator 42 are conveyed back into the filter cake 34 in screw conveyor 36 or screw conveyor 54 by means of conduits 56, 58 and 60.
The treatment agent from a source 62 may be sprayed as a molten liquid, added as a dry powder, or added as a vapor via conduit 64 to the relatively dry fiber particles exiting cyclone separator 42 in conduit 56, 58 and/or 60. In the alternative, the treatment agent may be added to the relative dry particles in conveyors 36 and/or 54. The mixture of relatively dry filter cake and solids in conveyor 36 is then fed to dryer 38 wherein the solids are reduced in size, fluffed and flash-dried by drying and conveying gas 40. At least a portion of the filter cake containing pulp and solids from separator 42 are directed by conveyor 54 through the dust chamber 44 before the treated pulp 46 is discharged from the system as a dry/treated pulp 46 which may be used in a conventional papermaking processes. After the pulp is treated with the agent, excess or unreacted agent may be removed from the treated pulp 46 by contacting the pulp with a water spray or quench spray (not shown).
FIG. 3 illustrates a further embodiment of the invention where dry-lap pulp in conduit 70 from pulp chest 72 is conveyed to a fan pump 74 where it is mixed with white water delivered via conduit 76 from a seal vessel 78. The white water is supplied to seal vessel 78 from cylinder former 80 via conduit 82. Seal vessel 78 provides a liquid level of white water sufficient to maintain a vacuum on the cylinder former 80.
Fan pump 74 conveys the mixture of pulp and white water to the cylinder former 80 where a web 84 is formed from the pulp. The web 84 is conducted through a series of nip rolls 86 which squeeze water from the web having a moisture content of about 85% down to a moisture content of about 60% by weight and then the web is conducted to dryer unit 88 wherein the web is dried. Agent 10 in particulate or molten form is added to the pressed web 90 from source 92 at a point in the dryer 88 wherein the pressed web 90 has a moisture content of less than about 20% by weight. The web 90 containing the agent is heated in dryer 88 to bring about reaction between the agent and fiber surfaces to provide a cellulosic fibrous web 96 having increased strength.
If desired, web 96 may be treated to remove excess or unreacted agent prior to storage, sale or further processing. Such treatment may include, for example, spraying the web with a hydrolyzing agent and further drying the web or heating the web to a temperature sufficient to vaporize any excess agent.
The following nonlimiting examples illustrate various aspects of the invention. Unless otherwise indicated, temperatures are in degrees Celsius, percentages are by weight and percent of any pulp additive or moisture is based on the oven-dry weight of the pulp.
EXAMPLE 1
Texarkana softwood kraft pulp having a moisture content of about 5% by weight was passed through a hammer mill in order to separate the fibers into a loose mat of individualized fluff pulp. The fluff pulp was treated with 1% by weight maleic anhydride (MAH) powder by adding the MAH and tumbling the mixture to uniformly distribute the powder in the fluff pulp. The pulp samples were placed in foil and cured for 10 minutes at temperatures ranging from 20° to 140° C. After curing the pulp, the pH of the pulp was adjusted to 9 and the pulp was rinsed twice with distilled water. The carboxyl content in milliequivalents per gram (mEq/g) of the treated and untreated pulp samples was determined by the relationship (mL of HCl-2.14 mL of HCl)×0.05 mEq/mL HCl/mass of fibers in grams=carboxyl content. The surface charge of the pulp samples was determined by the adsorption of a cationic polymer by the pulp. Results are given in the following table and are shown graphically in FIG. 4.
TABLE 1______________________________________MAHRun (wt. Curing Temp. Carboxyl Content Surface Charge.sup.1No. %) (° C.) (μEq/gram) (μEq/gram) (lb/ton)______________________________________1 0 20 35 1.70 5.52 1 20 35 1.30 4.23 1 65 37 1.57 5.14 1 80 39 2.35 7.65 1 95 45 2.25 7.36 1 105 45 2.66 8.67 1 115 50 3.00 9.78 1 140 48 2.81 9.1______________________________________ .sup.1 Surface Charge determined by the adsorption of dry diallyldimethylammonium chloride (DADMAC) powder per weight of fiber by titrating the treated fiber with DADMAC polymer having a weight average molecular weight of about 375,000 grams per mole sold under the tradename BUFLOC 536 which is commercially available from Buckman Laboratories, Inc of Memphis, Tennessee. The titration endpoint was identified with the point of zero streaming potential #after mixing the DADMAC with the pulp for 1 to 5 minutes.
This data shows that as the curing temperature is increased above 20° C., the carboxyl content and surface charge increase up to a maximum at a curing temperature of 115° C. A curing temperatures as high as 140° C., while providing a significant increase in the carboxyl content over the untreated fiber, did not provide a significant increase relative to a curing temperature of 115° C. for increasing the carboxyl content and surface charge of the fiber. The data also indicates that the surface charge as determined by the adsorption of DDMAC cationic polymer was almost double that of the untreated fiber at a curing temperature of 115° C., and that the surface charge increased by a greater relative amount than the carboxyl content of the pulp (170% versus 140%).
As illustrated in FIG. 4, the untreated pulp represented by point A had a carboxyl content of 35 μEq/gram and a surface charge of 1.7 μEq/gram whereas the treated pulp had a carboxyl content ranging from 35 to 50 for a surface charges ranging from 1.3 μEq/gram to a maximum at point B of 3.0 μEq/gram.
Circular handsheets containing the treated and control pulp samples were prepared according to TAPPI method T205, and the properties of the handsheets were determined. The results are given in the following table.
TABLE 2______________________________________ Basis Scott Normalized MAH Curing weight Bond Normalized GurleyRun (wt. Temp. (gram/ (E-3 Tensile DensometerNo. %) (° C.) m.sup.2) ft-lbf) (lbf/in) (sec/100 cc)______________________________________1 0 20 106.0 30.0 8.15 0.572 1 20 104.8 31.0 8.13 0.473 1 65 102.0 30.0 8.44 0.434 1 80 105.5 29.6 7.70 0.425 1 95 104.3 39.2 8.04 0.456 1 105 106.3 32.2 8.66 0.447 1 115 106.0 37.0 7.27 0.388 1 140 106.3 28.8 6.62 0.35______________________________________
The results show that the internal bond strength was maximized after curing the samples for 10 minutes at a temperature in the range of 90° to 120° C.. At 140° C. the bond strength decreased to below the level of the untreated sample. Thus, above 120° C., the tensile strength of the samples decreased.
The results of Table 2 are illustrated graphically in FIG. 5 and 6. In FIG. 5, curve U represents the carboxyl content of the untreated pulp versus temperature whereas curve T represents the variation in carboxyl content with curing temperature of pulp treated with 1% by weight maleic anhydride. In FIG. 6, point C represents the surface charge of untreated pulp and the points on curve W represent the surface charges of the maleic anhydride treated pulp at various curing temperatures. A maximum surface charge of 3 μEq/gram was obtained at 115° C. as represented by point D on curve W.
The maximum strength properties of the samples cured at intermediate temperatures was consistent with the effects of heating on the porosity of paper made from the samples. An increase in porosity or decrease in Gurley Densometer value was more evident when the samples were cured at 120° C. and above which reflects the relatively poor bonding achieved under such conditions. It is believed that the maximum tensile strength at about 100° C. represents the optimum curing conditions for the samples.
EXAMPLE 2
In the following runs, pulp samples of Texarkana softwood kraft pulp were treated with maleic anhydride powder in amounts ranging from 0 to 1% by weight. The moisture content of the samples was varied between 5 and 50% by weight. The samples were placed in foil and cured for 5 minutes at 100° C.. Circular handsheets containing the treated and untreated pulp samples were prepared according to TAPPI method T205. Results are given in the following table.
TABLE 3______________________________________Run MAH Moisture Surface Charge Breaking Scott BondNo. (wt. %) (wt. %) (μEq/gram) Length (m) (E-3 ft-lbf)______________________________________1 0 5 0.58 1,576 26.22 0.1 5 0.49 1,020 18.43 0.3 5 0.71 1,159 18.84 1 5 1.19 1,250 28.25 1 20 0.45 895 16.46 1 50 0.45 848 18.4______________________________________
As can be seen from the data, the surface charge density generally increased as the amount of maleic anhydride used to treat the pulp increased. Also, the higher moisture content samples exhibited a dramatic decrease in the surface charge, breaking length and internal bond over the samples treated with the same amount of maleic anhydride at a moisture content of only about 5% by weight.
EXAMPLE 3
Dry-baled bleached softwood kraft fibers were milled and fluffed in a hammer mill. Half of the fluffed fibers were retained as a "control" sample. The fluffed fibers were mixed with 1 percent by weight maleic anhydride powder based on the oven-dry weight of solids. The samples were each sealed in aluminum foil and heated at a temperature of 108° C. for 10 minutes. The samples were then redispersed in water, providing 1000 mL each of 2 weight percent solids suspension. Sufficient dilute NaOH was added to each slurry to raise the pH to 10. Each sample was then rinsed twice with distilled water using a Buchner funnel to rinse and dewater the pulp. The pulp samples were then re-slurried to 1000 mL in distilled water.
The density of carboxyl groups in each sample of suspended pulp was determined by titrating the samples with 0.05 N HCl to a pH of 3.0. In each case, the initial pH of the pulp suspension was adjusted to 8.0 before titration. Results are given in the following table.
TABLE 4______________________________________ Fiber mass Volume of 0.05 N Carboxyl ContentSample Description (grams) HCl (mL) (mEq/g)______________________________________distilled water 0.00 2.14 0.00control 0.814 3.25 0.068treated pulp 0.911 8.30 0.34______________________________________
Circular handsheets of the treated pulp and control were prepared according to TAPPI method T205 with levels of cationic potato starch equal to zero, 20 and 40 pounds per ton of pulp. Physical tests of the handsheets were conducted to determine breaking length, Scott internal bond, Gurley stiffness, apparent density and Z-directional tensile strength of the resulting paper. The results are given in Table 5.
TABLE 5______________________________________ Break- Z- Ap- ing Scott Direction- Gurley parent Length Percent Internal al Stiff- Density (meters) Stretch Bond Tensile ness (g/cm.sup.3) (TAPPI (TAPPI (TAPPI (TAPPI T- (TAPPI (TAPPISample T-494) T-494) 403) 541) T-543) T-220)______________________________________Controlstarch 1445 1.42 31.4 26.2 124.3 0.52(0 lbs/ton)starch 2288 2.60 61.2 60.2 100.9 0.52(20 lbs/ton)starch 2231 2.59 57.8 60.5 62.3 0.52(40 lbs/ton)Treated pulpstarch 2838 2.59 75.6 55.6 63.5 0.49(0 lbs/ton)starch 3592 2.74 85.0 62.5 179.1 0.50(20 lbs/ton)starch 3714 2.81 99.8 88.6 163.7 0.57(40 lbs/ton)______________________________________
These results show a substantial increase in the density of carboxyl groups in pulp fibers treated according to the invention compared to the untreated fibers. Treatment of pulp fibers according to the invention increased the breaking length by a factor of 2.0 and the Scott internal bond by a factor of 2.4. The addition of 20 lbs/ton cationic starch yielded an additional increase in breaking length to 3592 meters. No further benefit in breaking length was evident by increasing the starch level from 20 lbs/ton to 40 lbs/ton.
The results also show that the vastly improved strength properties achieved using the invention enable even greater improvement in the effect of adding starch. The tests conducted using treatment with the agent of the invention and starch show substantially better properties over use of starch alone.
EXAMPLE 4
In this example, samples of treated pulp were prepared from shredded office paper. The office paper included 50 wt.% xerographic paper prepared under alkaline papermaking conditions and 50 wt.% computer form bond paper prepared under acidic papermaking conditions. The mixture therefore represented a cross-section of office-type papers which are conventionally available for recycling.
The mixture of recycled paper was shredded into quarter-inch strips and pre-dried for 20 minutes at 105° C.. Three 40 gram samples of dry shredded strips were placed in aluminum foil bags. Sample 1 was mixed with 0.8 grams of maleic anhydride powder. Sample 2 was mixed with 0.8 grams of maleic acid powder. Sample 3 contained only shredded paper with no treatment chemicals. In each case, the sealed bags were shaken for 30 seconds to thoroughly mix the powders with the shredded paper. After mixing, the foil bags were placed side-by-side on a shelf in a convection oven for 15 minutes at 95° C.
The treated paper samples (1 and 2) were dispersed in 2 liters of tap water using a disintegrator according to TAPPI Method T205 using 50,000 revolutions in each case. The final pH was 7.5 for samples 1 and 2 and 9.0 for sample 3. Handsheets were prepared from the samples according to test Method T205 with the exception that drying of the hand sheets was conducted on a polished chrome surface heated to 105° C. with the sheets held on the surface with a fabric. The physical properties of the prepare handsheets are given in the following table.
TABLE 6______________________________________ Internal Bond Breaking lengthSample No. Treatment Chemical (10.sup.-3 ft.-lbf) (km)______________________________________1 maleic anhydride 106 4.152 maleic acid 87 3.873 control 93.6 4.07______________________________________
As shown in the foregoing table, the handsheets made from shredded paper treated with maleic anhydride (Sample 1) had significantly greater internal bond strength and breaking length than the untreated sample (Sample 3) and the sample treated with maleic acid (Sample 2). The sample treated with maleic acid had significantly lower bond strength and breaking length than the untreated and maleic anhydride treated samples.
Additional data was obtained for the same treated and untreated paper samples using a lesser degree of disintegration to disperse the samples (15,000 revolutions). In this case, handsheets were prepared with the further addition of 0,20 or 40 pounds per ton of cationic potato starch available from Cytec Technology Corporation of Wilmington, Del. under the trade name ACCOSIZE 72. The results are given in the following table.
TABLE 7______________________________________ Internal Bond Strength (10.sup.-3 ft.-lbf) 0 lb/ton 20 lb/ton 40 lb/tonSample No. Treatment Chemical starch starch starch______________________________________1 maleic anhydride 144.8 165.8 195.62 maleic acid 133.2 154.4 152.03 control 136.6 153.6 152.4______________________________________
As shown by the foregoing samples, there was a synergistic increase in bonding strength when a cationic starch was used with maleic anhydride to treat the samples. For the acid treated and untreated samples, the starch increased the bonding strength only about 17×10 -3 ft.-lbf over the untreated control sample at both 20 and 40 lb/ton of starch. Maleic anhydride treatment alone increased the bonding strength about 8×10 -3 ft.-lbf over the untreated control sample. However, at 20 lb/ton of starch, the bonding strength of the maleic anhydride treated sample increased 29×10 -3 ft.-lbf over the untreated control sample and increased 59×10 -3 ft.-lbf over the untreated control sample at 40 lb/ton of starch. These results were unexpected and clearly indicate the advantage of treating recycled pulp with maleic anhydride.
EXAMPLE 5
In order to compare the effect of treating paper with maleic anhydride as a powder and by means of a solution of maleic anhydride, 1% and 5% by weight maleic anhydride powder was added to blotter paper samples 2 and 3 respectively. Blotter paper was also dipped in solutions of maleic anhydride in acetone (samples 4 and 5) so that the total amount of maleic added to each sample was the same as in samples 2 and 3. Sample 1 was a control sample which was not treated. The samples made using the acetone solution of maleic anhydride were air-dried at room temperature. All of the samples were cured on a rotating cylinder at 110° C. for 60 seconds.
In order to determine the carboxyl content of the samples, the samples were hydrolyzed in distilled water, the impurities were extracted with dilute hydrochloric acid and the samples were thoroughly washed. The washed samples were then reacted with calcium acetate to liberate acetic acid and the acetic acid was titrated with HCl to provide the carboxyl content of the pulp. The results of the treatment are given in the following table.
TABLE 8______________________________________ Maleic CarboxylSample anhydride content Scott BondNo. Treatment (wt. %) (μEq/gram) (10.sup.-3 ft.-lbf)______________________________________1 none 0 4.16 26.22 dry powder 1 5.40 15.43 dry powder 5 9.12 14.24 acetone solution 1 4.84 20.85 acetone solution 5 6.73 22.0______________________________________
As shown by the foregoing samples, paper samples treated with powdered maleic anhydride (samples 2 and 3) had a significant increase in the carboxyl content compared to untreated samples and compared to samples treated with same amount of maleic anhydride from an acetone solution. In all of the maleic anhydride treated samples, the internal bond strength was reduced which indicated that the curing conditions were beyond the optimum time and temperature for effective treatment with maleic anhydride.
Having now described various aspects of the invention and preferred embodiments thereof, it will be recognized by those of ordinary skill that numerous modifications, variations and substitutions may exist within the spirit and scope of the appended claims. | Processes for increasing the strength of cellulosic fibers are carried out by contacting relatively dry cellulosic fibers with an agent in particulate or vapor form comprising a carboxylic acid cyclic anhydride at an elevated temperature for a time sufficient to significantly increase the bonding strength of the fibers. The treated fibers bond more readily to one another and they also hold wet and dry strength aids more strongly. Furthermore, the treatment does not significantly affect the internal chemical structure of the fibers so that paper made from the fibers exhibits overall improved dimensional stability. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to German Patent Application. No. 102008030233.3, filed Jun. 25, 2008, which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
The present invention relates to a gearshift device for a change-speed gearbox of motor vehicles comprising a gearshift lever and a so-called reverse gear block.
BACKGROUND
The gearshift lever located in the passenger compartment of a motor vehicle after installing the gearshift device is guided movably between positions which correspond to various gears of the change-speed gearbox. A coupling device such as a linkage or cable controls extends between the gearshift device and the change-speed gearbox in order to couple the position of gearshift forks of the change-speed gearbox to the position of the gearshift device. In order to ensure that one of the predefined positions of the gearshift lever actually corresponds exactly to a configuration of the gearshift forks in which a desired gear is engaged, an alignment of the coupling device is required. In order to be able to perform such an alignment exactly, it is desirable to be able to immobilize the gearshift lever in at least one position free from play.
It is known to implement a reverse gear block by providing a longitudinally displaceable hook on the gearshift lever, which, when the gearshift lever approaches its position corresponding to the reverse gear, impacts against a barrier in order to prevent any accidental engagement of reverse gear, which can overcome the barrier by displacement along the shaft of the gearshift lever and which prevents accidental disengagement of reverse gear by engaging behind the barrier. In order that the engagement of the gear behind the barrier takes place reliably, it must retain some play. Consequently, the gearshift lever is not completely immovable in the reverse gear position. The conventional locking of the gearshift lever in the reverse gear position is therefore not suitable for sufficiently immobilizing the gearshift lever for the purpose of alignment.
At least one object of the present invention is to provide a gearshift device which allows play-free immobilization of the gearshift lever for the alignment but at the same time allows the necessary play in the function mode. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.
SUMMARY
The at least one object, other objects, desirable features and characteristics, are achieved whereby in a gearshift device for a change-speed gearbox of a motor vehicle having a gearshift lever guided movably between positions corresponding to different gears. A locking member on the gearshift lever is displaceable in a first degree of freedom, the locking member on the gearshift lever is movable in a first degree of freedom between a normal position in which it allows a shifting movement of the gearshift lever and an alignment position in which it fixes the gearshift lever free from play.
The locking member is preferably additionally movable in a second degree of freedom between a locking position in which it blocks a shifting movement of the gearshift lever from a forward gear position into a reverse gear position, and a release position in which it allows movement from the forward gear position into the reverse gear position.
The locking member is preferably a sleeve surrounding a shaft of the gearshift lever. The first degree of freedom of the locking member is preferably a rotation about the shaft, the second degree of freedom is a movement in the longitudinal direction of the shaft.
In order to achieve freedom of play in the alignment position and to retain some play in the normal position, the locking member and shaft each have a contoured side surface, and in the normal position the contours of the contoured side surface intermesh in a complementary manner, whereas in the alignment position they do not do this.
If the first degree of freedom is a rotation as mentioned above, a changeover between engagement and nonengagement of the contours can easily be achieved by the contoured side surfaces of the locking member and the shaft not lying opposite to one another in the alignment position. Instead, in the alignment position projecting contours of the locking member or the shaft preferably contact a flat side surface of the shaft or the locking member.
In order to be able to transfer the sleeve forming the locking member from the normal position into the alignment position without needing to detach this from the shaft, the shaft preferably comprises a section guiding the sleeve in a rotationally fixed manner, and a section allowing a rotation of the sleeve about the shaft when the sleeve is located at the height of said shaft. In the release position, however, the sleeve is preferably located on the guiding section.
A spring can be provided to act upon the sleeve along the shaft from the section allowing rotation in the direction of the guiding section. This ensures that the sleeve cannot accidentally arrive at the section allowing rotation.
In order to unlock the locking member when using the locking member as a reverse gear block and be able to switch between forward and reverse gear, a control element coupled to the sleeve is preferably attached to a handle of the gearshift lever.
The freedom of movement of the control element is preferably not sufficiently large to entrain the sleeve into the section allowing rotation. The driver cannot therefore accidentally change over between the alignment and the normal position; if, however, the locking member is exposed during assembly of the vehicle or during a repair, such a changeover can be performed conveniently by pulling the locking member on the section allowing rotation and turning it there.
As further security against an undesirable transition of the locking member onto the section allowing rotation, a latching device can be provided, which can be engaged by a movement of the locking member from the section allowing rotation to the guiding section. Such a latching device can preferably only be engaged when the locking member is located in the alignment position.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and:
FIG. 1 shows a section through a gearshift device according to the invention in the longitudinal direction of its gearshift lever;
FIG. 2 shows a section transverse to the gearshift lever along the plane designated by II-II in FIG. 1 which shows the locking member in the alignment position;
FIG. 3 shows a section similar to FIG. 2 with the locking member in the normal position;
FIG. 4 shows a section similar to FIG. 1 with the locking member in the normal position; and
FIG. 5 shows a partial section of the gearshift device along the longitudinal axis of the gearshift lever in a plane perpendicular to the plane of intersection of FIG. 1 .
DETAILED DESCRIPTION
The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background and summary or the following detailed description.
The sectional view in FIG. 1 shows a gearshift lever 1 , which is mounted in a holder of a motor vehicle fixed to the bodywork, not shown in detail, so that it is pivotable by means of a ball joint 2 or another joint in two degrees of freedom, hereafter designated as selecting or shifting degree of freedom. The gearshift lever 1 has an elongate shaft 3 , which has a handle 4 at its end facing away from the ball joint 2 . The shaft 3 is substantially composed of a cylindrical tube 5 extending between the ball joint 2 and the handle 4 and a guiding body 6 of approximately square cross section, which encloses a lower section of the tube 5 adjacent to the ball joint 2 .
A flexible bellows 9 surrounds an upper section 7 of the shaft 3 protruding from the guiding body 6 and is fastened to the guiding body by means of a peripheral collar 8 . The shaft extends through an opening in a transmission tunnel not shown and the outer edge of the bellows 9 is connected to the edge of the opening to close off the interior of the transmission tunnel toward the passenger compartment.
A helical spring 10 is supported on the collar 8 , which helical spring acts upon a locking sleeve 11 displaceable on the shaft 3 against the guiding body 6 so that the guiding body 6 engages in an internal cavity of the locking sleeve 11 .
A pull rod 12 extends in the hollow interior of the shaft 3 . A hook 13 angled at one end of the pull rod 12 engages through a slot of the tube 5 into the interior of the locking sleeve 11 . An upper end of the pull rod 12 is connected to an actuating ring 14 , which is mounted displaceably below the handle 4 on the shaft 3 .
The locking sleeve 11 has two hooks 15 on one side, which, in the configuration shown, engage with their cylindrical tip 31 parallel to the shaft 3 in a manner free from play in a hole on an oblique surface facing away from the shaft 3 of a fixed web 17 in relation to the transmission tunnel. A hook 35 on the opposite side of the locking sleeve 11 does not engage.
The web 17 is here part of a guiding link in which shift and select gates orthogonal to one another are cut out in a manner known per se to guide the movement of the shaft 3 extending through these gates in the shifting or selecting degree of freedom. The select gate extends in the plane of intersection of FIG. 1 . In the configuration shown the gearshift lever 1 is located at the end of the select gate 18 , from which the shift gate of the reverse gear branches off. Due to the engagement of the two tips 31 in the holes of the web 17 , the locking sleeve 11 is fixed free from play on the shift link in the shifting degree of freedom and in the selecting degree of freedom.
FIG. 2 shows a section through the locking sleeve 11 and the shaft 3 in the configuration of FIG. 1 along the plane designated by II-II in FIG. 1 . The guiding body 6 has a substantially rectangular cross-section with ribs 22 , 23 projecting on two opposite side surfaces 20 , 21 . The ribs 22 on the side surface 20 each have a flat front face parallel to the side surface 20 , which each has a flat rib 24 on an inner side of the locking sleeve 11 opposite to a part of its width. The ribs 23 have a stepped front surface beyond over the side surface 21 . The respectively further projecting sections 25 abut against the inner surface of the locking sleeve 11 .
The other two opposite side surfaces 27 , 28 of the guiding body 6 have a different length to the side surfaces 20 , 21 . The side surface 27 is provided with flat ribs 29 while the other side surface 28 is flat. The flat side surface 28 contacts ribs 30 of an opposite inner surface of the locking sleeve 11 while the ribs 29 contact a flat inner surface of the locking sleeve 11 . The locking sleeve 11 thus rests free from play on the guiding body 6 . In this way, the gearshift lever 1 is fixed free from play in its two degrees of freedom and a coupling device, not shown, which is known per se, and connects the gearshift lever 1 to the gearshift forks of the change-speed gearbox can be aligned without the gearshift lever 1 yielding to the forces which occur during alignment.
After the alignment, the fixing of the gearshift lever 1 is released by grasping the locking sleeve 11 by the hand and lifting it sufficiently far against the restoring force of the helical spring 10 that the guiding body 6 no longer engages in the locking sleeve 11 . In this position, the locking sleeve 11 is freely rotatable about the shaft 3 . If this is turned through approximately 180° and then released, it slides onto the guiding body 6 again in the orientation shown in cross section in FIG. 3 and shown in longitudinal section in FIG. 4 . The flat side surface 28 and the side surface 20 with unstepped ribs 22 now lie opposite flat inner surfaces of the locking sleeve 11 , the ribs 24 lie opposite the sections 26 , and the ribs 30 each engage between the ribs 29 . The engagement of the guiding body 6 in the locking sleeve 11 is thus play-retaining transversely to the shaft 3 in two directions, in the shifting and in the selecting degree of freedom, so that there is no risk of the locking sleeve 11 jamming on the guiding body 6 .
The holes in the web 17 which can be identified in the plan view in FIG. 3 are now empty; the hooks 15 do not engage on the side of the locking sleeve 11 facing away from the web 17 . Instead, a short rib 36 is formed on the web 17 .
When the gearshift lever is moved from the alignment position at the end of the select gate 18 into the shift gate of the reverse gear running parallel to the web 17 , the hook 35 slides along on the web 17 and ultimately engage behind the rib 36 . If, on the other hand, it is moved into the select gate, the hook 35 jumps down from the web 17 . A movement of the gearshift lever 1 back to the end of the select gate is only possible if the locking sleeve 11 is raised by pulling up the actuating ring 14 .
As the preceding description shows, the locking sleeve 11 provides a double function in this gearshift device, on the one hand, in the orientation in FIG. 2 it serves as a play-free fixing of the gearshift lever 1 which allows alignment of the coupling device and on the other hand, in the orientation in FIG. 3 , it functions as a reverse gear block which retains play with respect to the guiding body 6 in order to be reliably movable along the shaft 3 and reliably return to the locking position when the actuating ring 14 is released.
The restoring force of the helical spring 10 can be sufficient to reliably prevent the case that, when the actuating ring 14 is pulled up and the locking sleeve 11 is in its release position, the locking sleeve 11 is moved so far upward that it loses its engagement with the guiding body 6 and becomes rotatable. In order that pulling up the actuating ring 14 is not made unnecessarily difficult for the driver, it can however be desirable to make the restoring force of the helical spring 10 small.
FIG. 5 shows a partial section through the gearshift device 1 along the plane designated by V-V in FIG. 1 . Formed inside the guiding body 6 is a resilient tongue 32 extending in the longitudinal direction of the shaft 3 , which has a beveled latching projection 33 at its tips. When the locking sleeve 11 is located in the orientation in FIG. 2 , the tip of the latching projection 33 dips into a recess 34 on an inner surface of the locking sleeve 11 . The locking sleeve 11 cannot therefore slip away from the guiding body 6 . This is particularly advantageous when the shaft 3 with tube 5 , guiding body 6 , and ball joint 2 but without the handle 4 forms a preassembled structural unit, which is to be mounted in the vehicle in its entirety since loss of the locking sleeve 11 before attachment of the handle 4 can thus be prevented.
Nevertheless, the locking sleeve 11 can be pulled away from the guiding body 6 after alignment with no difficulties since a large part of the tongue 32 is exposed below the locking sleeve 11 and can be pressed in by hand to cancel the latching and pull the locking sleeve upwards from the guiding body 6 . Finally, the locking sleeve 11 can be turned through approximately 180° and placed on the guiding body 6 again to produce the normal position.
In the normal position, an internal surface of the locking sleeve 11 , having no recess 34 , is located opposite the latching projection 33 . In the normal position, therefore latching is not possible but also is not necessary.
While at least one exemplary embodiment has been presented in the foregoing summary and detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. | A gearshift device for a change-speed gearbox of a motor vehicle, includes, but is not limited to a gearshift lever guided movably between positions corresponding to different gears, on which a locking member is displaceable between a locking position in a first degree of freedom in which it blocks any movement of the gearshift lever from a forward gear position into a reverse gear position, and a release position in a first degree of freedom in which it allows movement from the forward gear position into the reverse gear position. The locking member on the gearshift lever is movable in a second degree of freedom between a normal position in which movement between release position and locking position is possible and an alignment position in which it fixes the gearshift lever free from play. | 8 |
TECHNICAL FIELD
[0001] The present invention relates to semiconductor memory devices. More particularly, the present invention relates to improving data management in semiconductor memory devices, such as flash memory devices.
BACKGROUND OF THE INVENTION
[0002] Non-volatile memory is a type of memory that can retain data and information even when power is not applied. An example of non-volatile memory that is being used in a variety of applications, such as cellular phone technology, is “flash memory.” Flash memory is a form of electrically erasable programmable read-only memory (EEPROM), where data can be written in bytes and erased in blocks of memory. The blocks of memory typically range from 8 kBytes to 1 MByte in size. The cell density of flash memory devices can be very high, often as high as conventional dynamic random access memory (DRAM) cells, since in conventional flash memory a single floating gate structure is used for each memory cell. Flash memory devices also have relatively fast data access times. In the past, flash memory has been used in applications such as storing basic input/output system (BIOS) information in personal computers. However, with improvements in programming capabilities, and the continually increasing demand for persistent and low-power memory devices, the application of flash memory in many other areas has expanded very rapidly.
[0003] As previously mentioned, one such application is in cellular phones. At one time, cellular phones were only limited to voice communication. Now, cellular phones provide Internet access and web browsing capabilities, allow a user to capture and store computer graphic images, capture and playback video images, and provide personal digital assistant (PDA) capabilities. As a consequence, cellular phones need to be able to store different types of data and information. For example, whereas older cellular phones would only need to store data representing phone numbers, newer cellular phones need to store in addition to phone numbers, voice information, computer graphic images, small applications (e.g., Java applets) downloaded from the Internet, and the like.
[0004] The various data objects that must be stored by the flash memory have different characteristics. For example, data such as phone numbers are generally small segments of data having uniform length. Other data can be variable in length, such as voice information, where the amount of memory used depends on the length of voice information recorded. Data can be packetized, as in the case where data is downloaded from the Internet. Additionally, the amount of memory consumed by data such as voice information and image files can be considerable, spanning multiple blocks of flash memory. Application code, such as a Java applet, is unique in that the binary code must be stored contiguously in flash memory to allow for the code to be executed by a processor directly from the flash memory.
[0005] Flash memory, which is non-volatile, and has low operating power, is perfectly suited for data and information storage applications such as in cellular phones where conservation of power is very desirable. However, the operating characteristics of flash memory must be adapted to facilitate storage of the different types of data and information previously described.
[0006] Flash memory, although providing many of the characteristics required for applications in portable and remote (wireless) devices, have unique operational characteristics that need to be considered. For example, because of the floating gate structure of conventional flash memory cells, data cannot be simply overwritten. The memory cells must be erased prior to writing new data. Also, as previously mentioned, flash memory devices are designed to erase data in blocks of memory cells, rather than on a cell-by-cell basis. Thus, although only a portion of the memory cells of a block need to be updated, the entire block must be first erased before programming the new data. The process of erasing an entire block of memory cells and programming new data takes a relatively long time to complete, and deferring an erase operation is often desirable. Additionally, erasing the entire block is a problem, however, in the case where another portion of the memory cells of the block do not need to be updated. Another issue related to flash, and other floating gate memory devices, is that these memory cells have a limited life-cycle where repeated cycles of erasing and programming degrade memory cell performance. Eventually, the cell performance is degraded to such a degree that the memory cell can no longer be used to store data.
[0007] In an effort to facilitate the use of flash products in applications such as cellular phones, memory management software interfaces have been developed to make the management of data storage in flash devices transparent to the user. The memory management software carries out various operations in the flash memory such as managing code, data and files, reclaiming memory when insufficient erased memory is available for programming new data, and wear-leveling flash blocks to increase cycling endurance. Memory management typically includes functions to support storage of parameter data for EEPROM replacement, data streams for voice recordings and multimedia, Java applets and native code for direct execution, and packetized data downloads. In addition to these operations, the memory management software often ensures that in the event of a power loss, previously programmed data is not lost or corrupted. An example of this type of memory management software is Intel® Flash Data Integrator (FDI) software.
[0008] Although conventional flash memory management software has succeeded in increasing the flexibility of flash memory, there is still room for additional improvement. Conventional memory management software has limitations in the area of data management. For example, in some conventional flash memory management software, the memory space of a flash device is partitioned into fixed memory address ranges and either code or data is associated to each of the ranges. Once set at compile time, the range and the type of associated data cannot be changed without recompilation. Consequently, if at a later time a different partitioning between code and data is desired, the ranges defined for the two types of data cannot be modified unless software is recompiled. Additionally, although different flash memory management software perform many of the same functions, the process by which the functions are performed can be very different, with some being more efficient or faster than others.
[0009] Conventionally, data stored across multiple segments is organized hierarchically. FIG. 1 flash memory storage 100 grouped into volumes 104 . As previously described, to store both programs and data, the memory storage 100 is partitioned into a code volume 106 and a data volume 108 . Both the code volume 106 and the data volume 108 may comprise a number of code blocks 109 and data blocks 111 . Of these, a data block 111 of the data volume 108 , is shown in detail to show how multiple segment data is stored hierarchically by a conventional method. Each data block 111 comprises a group table 112 which serves as a directory for a second level of hierarchy, the sequence tables 116 . Each sequence table 116 in turn serves as a directory for a number of data read/write units 120 , in which data actually are stored.
[0010] Unfortunately, the hierarchical arrangement shown in FIG. 1 presents at least two concerns. First, writing data to a data read/write unit 120 not only necessitates erasing and rewriting the block or blocks of flash memory where the data read/write unit 120 resides, but also can invalidate tables in which the data read/write units 120 are indexed. In particular, in the hierarchical system shown in FIG. 1 , changing data in the multiple segment data object can necessitate changing both the sequence table 116 in which the relevant data read/write units 120 are indexed, and the group table 112 in which the sequence tables 116 are indexed. Therefore, writing to a data read/write unit 120 stored in even a single flash memory block 100 may result in having to erase and rewrite not only that block, but also having to erase and rewrite other blocks 100 where the sequence table 116 and group table 112 reside. Having to rewrite not only the data read/write units 120 , but also two levels of tables is both time consuming and also consumes the useful life of the flash memory cells by necessitating even more erase and write cycles.
[0011] Second, this hierarchical structure restricts the size or number of data segments that can be stored, segments that can be stored, which are fixed due to the system configuration and cannot be changed until the system configuration is changed, the software is recompiled, and the data volume is formatted again. In this hierarchical structure, there is a maximum number of entries for both a group table 112 and a sequence table 116 . Accordingly, if a segment of data requires more data read/write units 120 than can be listed in a sequence table 116 , or the number of read/write units 120 used fills more sequence tables 116 than can be listed in a group table 112 , that element of data cannot be stored as a single data element. At the same time, if the data segments are very small, because of the maximum number of entries allowable in a sequence table 116 , part of a volume may be unused because there cannot be enough table entries to point to all the separate entries to be made.
[0012] Therefore, there is a need for alternative memory management processes to allow for more flexibility in data storage in flash memory and related devices. It is to this need that the present invention is directed.
SUMMARY OF THE INVENTION
[0013] The present invention is directed to management of multiple segment data objects. In a flash memory or other non-volatile memory devices, the present invention provides a method for non-linear storage of relatively large bodies of data using a data structure having a plurality of index table objects and a plurality of data segment objects. Each index table object contains an index table header and an index table. The invention uses an index table headers to specify parameters about each of the index table objects, index tables, and data object therein stored, and an index table to reference the data segment objects referenced by the index table object. Each data segment object contains a data segment header and data. The index table objects and data segment objects can be stored across a plurality of container objects, and the container objects themselves can be stored in multiple memory blocks.
[0014] More specifically, the index table header of index table object contains fields specifying the state of the index table object, the size of the header, a designation that the data is an index table object, a key uniquely signifying the data object, a key uniquely signifying this index table object, the size of the associated index table, a key specifying the next index table object, and an optional time stamp. The index table contains references to the data segment objects in which data is stored. The index table object or the data segment objects can be stored together or in separate locations in memory. One index table object can be used to define the parameters and store the references for all of the data segment objects of a multiple segment data object, or multiple index table objects can be used to reference to the data segment objects.
[0015] The data segment objects can be stored together or in separate locations in memory. A data segment header contains fields specifying the state of the segment data object, the size of the header, a designation that the data is a data segment object, a key uniquely signifying the data segment object, a key signifying the index table object referencing the data segment, a key uniquely signifying the data segment object, the size of the portion of the data, and an optional timestamp. Actual data is stored following the data segment header. Data segment objects can be stored in multiple container objects, and those container objects can themselves be stored in different flash blocks, and thus are limited only by the capacity of the memory system itself, and not by constraints inherent in the data management system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a block representation of a conventional method of storing data in multiple segments in a flash memory device.
[0017] FIG. 2 is a block representation of blocks of flash memory being assigned to volumes and, in turn, as allocated as linear objects and container objects.
[0018] FIG. 3A is a block representation of a series of linear objects and container objects, the container objects storing a plurality of single segment data objects and a multiple segment data object, the multiple segment data object being stored in accordance with an embodiment of the present invention.
[0019] FIG. 3B is a block representation of an index table object in accordance with an embodiment of the present invention.
[0020] FIG. 3C is a table showing data states used by the index table objects and data segment objects in accordance with an embodiment of the present invention.
[0021] FIG. 3D is a block representation of a data segment object showing a data segment header and a data section in accordance with an embodiment of the present invention.
[0022] FIG. 4A is a block representation of two multiple segment data objects each using a single index table object to index their data segment objects in accordance with an embodiment of the present invention.
[0023] FIG. 4B is a block representation of a single multiple segment data object using two index table objects to index its data segment objects in accordance with an embodiment of the present invention.
[0024] FIG. 5 is a block representation of a multiple segment data object stored using a single multiple index table objects to show the relationship between the index table objects and the data segment objects in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Embodiments of the present invention are directed to a memory management operation and structure that provides flexibility in handling multiple segment data objects. In the following detailed description of exemplary embodiments of the invention, reference is made to the accompanying drawings, which form a part hereof, and in which are shown, byway of illustration, specific exemplary embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. However, it will be clear to one skilled in the art that the invention may be practiced without these particular details. Other embodiments may be utilized and modifications may be made without departing from the spirit or scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims.
[0026] FIG. 2 shows a data architecture 200 according to an embodiment of the present invention. The data architecture 200 can be used in a flash data manager (FDM) process to handle data objects in a flash memory device. The data architecture 200 associates FDM volumes 204 to the physical flash memory blocks 202 of one or more flash memory devices. Generally, the FDM volumes 204 can be variable in size, and may be modified by a user subsequent to compile time of the user's application. As a result, the boundaries of an FDM volumes 204 can be adjusted during run time of an application. The FDM volumes 204 can also span multiple flash memory blocks 202 and have boundaries that do not need to correspond to flash memory block boundaries. However, in this case, additional overhead is required to process partial flash memory blocks during erasing and writing operations. A more detailed description of the FDM volumes 204 and object management thereof is provided in commonly assigned, co-pending U.S. application Ser. No. ______, entitled “DYNAMIC VOLUME MANAGEMENT,” to Wong, filed Aug. 29, 2002, which is incorporated herein by reference.
[0027] Each of the FDM volumes 204 , such as Volume 1 206 , can include linear objects 208 and container objects 212 . In embodiments of the present invention, partitioning the memory space of a flash memory into two regions, one for linear data and the other for non-linear data, is not necessary. Consequently, linear objects 208 and other objects, in the form of container objects 212 , can be stored anywhere within the available memory space of a flash memory. Embodiments of the present invention allow for more flexible use of the available memory space of a flash memory device, thus, providing the ability for efficient linear and non-linear data storage. The memory space of the flash memory device can be utilized in an open manner, storing data objects in the available memory space independent of the particular type of data, rather than accommodating a fixed partitioned memory space where the location at which data is stored in memory is governed by the particular data type (i.e., either linear or non-linear).
[0028] FIG. 3A shows in more detail the contents of the container object 212 according to an embodiment of the present invention The container object 212 stores non-linear data in a “linear” fashion, thereby enabling linear and non-linear data to be inter-mixed throughout the available memory space of the flash memory device. In a container object 212 providing for both SS data objects 304 and MS data objects, there are three types of structures: the SS data objects 304 and the MS data segment objects 308 , and an MS index table objects 312 . As will be further explained, the index table objects 312 comprise an index table header and an index table which need not be stored contiguously. However, for the sake of simplicity of some of the figures, the components of the index table object 312 are represented as being contiguously stored as a single object. SS data objects 304 are relatively small and have data self-contained in a single segment of the memory space. For example, an SS data object 304 might store a telephone number in a user telephone book. SS data objects 304 can be used to store data having a length less than one read/write unit or having a length of multiple read/write units, depending on the expectations of the data to be handled. A read/write unit is typically the minimum byte size that can be stored in memory and perform flash device input/output operations. Additionally, the SS data objects 304 allow for updating “in place” by writing to reserved or erased memory within the memory space allocated for an SS data object 304 . In place updating avoids the need to reallocated a new data object whenever data needs to be updated. The SS data objects 304 further provide variable length updating capability so that new data can be of a different length than the data being updated. Management of SS data objects 304 are discussed in greater detail in commonly assigned, co-pending U.S. patent application Ser. No. ______ entitled “SINGLE SEGMENT DATA OBJECT MANAGEMENT,” to Wong et al., filed Aug. 29, 2002, which is incorporated herein by reference.
[0029] On the other hand, each of the MS data segment objects 308 store portions of multiple segment data objects which store relatively larger data objects such as graphics images, voice data files, and other larger, non-application code data which can be stored in a nonlinear fashion. Because the MS data segment objects 308 comprise part of an MS data object, the MS index table object 312 identifies a plurality of MS data segment objects 308 storing the MS data object. Using embodiments of the present invention, the length of MS data object is flexible, and writing or updating data requires only changing the affected data segment objects and the affected index table object or objects. Therefore, the data storage is not restricted by a table using a fixed number of entries that would limit the number of MS segments that can be included, or the maximum length of the MS data object as a result of there being a limited number of MS data segment objects allowed.
[0030] More specifically, FIG. 3A shows a container object in which a multiple segment data object is stored according to an embodiment of the invention. In the example shown in FIG. 3A , a single index table object 312 is used to index the data segment objects 308 of a multiple segment data object. The single index table object 312 includes header information and reference information for the actual data segment objects 308 storing the actual data of the multiple segment data object which will be explained in more detail in connection with FIG. 3B . The single index table object 312 is identified in FIG. 3A as “MST X-1,” to indicate that the index table object references data object X, and the index table object 312 represents the first index table object used to reference the data object. Because only a single index table object 312 is used to index data object X, MST X-1 will be the only index table object for this multiple segment data object. The data segment objects 308 indexed by index table object MST X-1 312 include MS X-1-1, MS X-1-2, MS X-1-3, MS X-1-4, and MS X-1-N, indicating that each segment is part of data object X, are referenced by the first index table object of data object X, and comprise data segment objects 1 through N of the data segment objects referenced by the first index table object.
[0031] Although only one multiple segment data object is shown, it will be appreciated that such a data volume could comprise many data objects, each of whose data segment objects are indexed by their own index table objects. Also, in the example shown, the data object has only one index table object, but the present invention places no limits on the number of index table objects that can be used to reference data segment objects comprising parts of data objects that can be created and stored.
[0032] FIG. 3B shows in more detail the components of the index table object 312 , showing both the index table header 313 and the index table 329 components. In one embodiment of the invention, there are eight fields in the index table header 313 :
State 314 =State of the index table object; HeaderLength 316 =Length of index table object; ObjectType 318 =Designation of multiple segment index table object; DataObjectKey 320 =Unique data object identifier; IndexTableKey 322 =Unique identifier for this index table object; IndexTableSize 324 =Size of the index table; NextIndexTableKey 326 =Identifier of next index table object—this particular NextIndexTableKey field stores a NULL value to indicate that this index table is the sole index table for the data object; and TimeStamp 328 =optional timestamp field.
[0041] The index table header 313 provides operational parameters of the multiple segment data object. Again referring to the commonly assigned, co-pending U.S. patent application Ser. No. ______, entitled “SINGLE SEGMENT DATA OBJECT MANAGEMENT,” to Wong et al., filed Aug. 29, 2002, which is incorporated herein by reference, the MS index table header 313 includes analogous content as the “single segment data object header” used to define the parameters of single segment data objects.
[0042] With respect to the State field 314 , FIG. 3C shows a table of states of the index table object 312 according to an embodiment of the present invention. In summary, the “EMPTY” state indicates free erased memory space available for writing. The “WRITING_HDR_LEN” state indicates that a header length is being written. The “WRITING_HDR” state indicates that the data object header is in the process of being written, such as writing the object state, but there is currently no data stored. The “WRITTEN_HDR” state indicates that the header is complete. The “WRITING_DATA” state indicates that data is being written and the data size is known. The “WRITTEN_DATA” state indicates that data has been written but not yet marked as valid. The WRITTEN_DATA state distinguishes between a copy of an object and the original object during the data copying process, in the event power loss occurs during a reclamation process or an update process. The WRITTEN_DATA state also distinguishes the completed state of the object during the creation of the object for the first time in the event of power loss recovery. The VALID_DATA state indicates that the stored data is valid. The INVALID_DATA state indicates that the data is freed and is eligible for reclamation. As will be explained in more detail below, the granularity of the object states facilitates a power loss recovery process that can be used to recover data in the event of power loss and ensure valid data.
[0043] As shown in FIG. 3C , the state of the index table object 312 can be represented by a binary value. Each state change clears a single bit of the binary value. As the state of the data object changes over time, the FDM updates the state field to reflect data transitions from one state to another by programming the value corresponding to the new state. As the state of the data object transitions, for example, from an EMPTY state to a WRITING_HDR_LEN state, and where the least significant bit (LSB) corresponds to the WRITING_HDR_LEN state, the data of the State field 312 will change from 1111 1111 to 1111 1110. As known by those of ordinary skill in the art, in the case of NOR flash memory devices, an unprogrammed (i.e., erased) memory cell of flash memory is represented by a value of “1” and a programmed memory cell is represented by a value of “0”. For NAND flash memory devices, this process is inverted. Consequently, in updating the state from EMPTY to WRITING_HDR_LEN, the value 1111 1110 can be written directly to the state field without the need for erasing any cells because only the LSB needs to be programmed to indicate a change in state. The other bits remain unprogrammed. As the state transitions, each succeeding bit gets programmed to reflect the change in states. For example, if the second to the LSB corresponds to a WRITING_HDR state, then the data of the State field 314 is modified from 1111 1110 to 1111 1100 when the state of the data object transitions from the WRITING_HDR_LEN state after the header record and state have been written. It will be appreciated that the previous example was provided for the purpose of illustration, and the correspondence of bits to states can be modified without departing from the scope of the present invention. Consequently, the foregoing example is not intended to limit the scope of the present invention to any particular embodiment.
[0044] The index table header 313 ( FIG. 3B ) also can include HeaderLength field 316 . The HeaderLength field 316 specifies the length of the index table header 313 , not including the length of the index table 329 . Because fields such as the TimeStamp 326 are optional, the index table header 313 can vary in length, thus the length of the index table header 313 needs to be indicated. The index table header 313 also includes an ObjectType 318 identifier which, in this case, signifies that the object is an multiple segment index table object as opposed, for example, to a data segment object 308 or a single segment data object 304 . A process for storing single segment data objects is described in the previously incorporated commonly assigned, co-pending U.S. patent application Ser. No. ______, entitled “SINGLE SEGMENT DATA OBJECT MANAGEMENT,” to Wong et al., filed Aug. 29, 2002.
[0045] A DataObjectKey field 320 uniquely identifies the data object for retrieval by the system The MS index table header 313 can also include an IndexTableKey 322 which uniquely identifies the index table object, and an IndexTableSize field 324 which specifies the length of the index table 329 , which will be further described below. The next to last field is the NextIndexTableKey field 326 . A multiple segment data object can be stored using a plurality of index table objects. In such a case, as will be described below, the index table header 313 includes the NextIndexTableKey field 326 to identify the next index table object used to index data segment objects of the data object. However, in the present example, a single index table object 312 is used to define and index all the data segment objects 308 storing the data of the data object. Accordingly, in this embodiment, the NextIndexTableKey field 326 carries a NULL value to indicate there is only one index table object 312 in the data object. Finally, the TimeStamp field 328 is an optional field which can be used to signify the last time the MS data object or the index table object 312 was last written or revised.
[0046] Following the index table header 313 in the index table object is the index table 329 . Although the index table header 313 and the index table 329 need not be contiguously stored, they are shown as contiguously stored in FIG. 3B for simplicity of illustration. Index entries 330 in the index table 329 identify the data segment objects 308 storing the data. In the embodiment shown, each index entry 330 has two components. The first component is a container identifier 331 . Using embodiments of the present invention, as previously described, data objects can be stored across multiple different container objects. Accordingly, the container identifier 331 identifies the container object in which the data segment object 308 is stored. The second component is a data segment key 332 , which specifies the unique identifier of the data segment object 308 . This unique identifier for the data segment object 308 also appears in the data segment header which will be described below. More specifically, the data segment key 332 references each data segment object 308 by the data object key, the index table key, and each segment's own segment key of the segments indexed by the index table 329 . Considering the data segment objects 308 shown in FIG. 3B , for example, “MS X-1-1” has a key of X-1-1, signifying it is associated with data object X, is referenced by the first index table header and index table, and is the first segment indexed. Similarly, “MS X-1-2” has a key of X-1-2, signifying it is associated with data object X, is referenced by the first index table object, and is the second segment indexed.
[0047] It will be appreciated that, in this example using only one index table object, all of the data keys will implicitly specify that the segments are associated with the first index table object and with one data object. The index entries 330 do not actually specify the data object or the index table object because these are identified by appropriate fields in the index table header 313 . Drawing from these fields in the index table header 313 , therefore, the index entries 330 need only specify the container object and the data segment key to uniquely identify each data segment object 308 . As will be explained below, using embodiments of the present invention, data segment objects 308 , may be part of and reference different data objects and/o different index table objects.
[0048] It should be noted that embodiments of the present invention do not restrict the number of data segment objects 308 that can comprise a multiple segment data object. Accordingly, the size of the data object can be varied by creating data segment objects 308 , adding entries 330 in the index table 329 to index the additional data segment objects, and changing the index table size 324 in the index table header 313 of the index table object 312 .
[0049] FIG. 3D shows in greater detail the structure of the MS data segment objects 308 . Each of the data segment objects 308 comprises two sections, as shown for MS data segment object MS X-1-1 352 : a data segment header 354 and a data section 358 . The data segment header 354 comprises eight fields, which one will appreciate are somewhat similar to the fields in the index table header 313 ( FIG. 3B ). First, a State field 360 stores the state information for the data segment object, the content of which is listed in FIG. 3C . In this embodiment of the invention, the defined states are identical to those previously described in connection with FIG. 3C for the state information stored in the State field 314 of the index table header 313 ( FIG. 3B ).
[0050] In this embodiment of the invention, the data segment header 354 ( FIG. 3D ) also includes a HeaderLength field 362 which indicates the length of the header 354 . Because fields such as the TimeStamp 374 are optional, the data segment header 354 can vary in length, thus the length of the header needs to be indicated. The data segment header 354 also includes an ObjectType 364 identifier which, in this case, signifies that this object is a data segment object.
[0051] A DataObjectKey field 366 uniquely identifies the data object of which the data segment object 352 is a part. In this embodiment, the data segment header 354 ( FIG. 3D ) can also include an IndexTableKey 368 which identifies the index table (not shown) which indexes the data segment object 352 . The data segment header 354 also comprises DataSegmentKey 370 , which is the same identifier assigned to this data segment object 352 and appearing in the entry 330 ( FIG. 3B ) in index table 329 for this particular data segment object. The next to last field is the DataSegmentSize field 372 which specifies the size of the data segment object 352 which, according to embodiments of the present invention, can be of variable length. The TimeStamp field 328 is an optional field which can be used to signify the last time the data segment object 352 was last written or revised. Finally, the data section 358 of the data segment object 352 contains the actual data stored in the segment.
[0052] Various processes of the FDM use the information in the index table header 313 ( FIG. 3B ) and the data segment header 354 ( FIG. 3D ) are used by various processes of the FDM in managing the data objects. A power loss recovery process uses the state information for data recovery in the event of a power failure. When a power loss recovery process is performed, the saved data can be restored by examining the state field. A power loss recovery process can make the determination on how to take action based on the state of the index table object as reflected in the index table header 313 and the data segment object as reflected in the data segment header 354 . For example, assuming that the object states shown in FIGS. 3C , only when the data object has an EMPTY, VALID_DATA, or WRITTEN_DATA state will no action be taken during the power loss recovery process. For all other object states, it is assumed that parts of the data object are unreliable and are ignored by skipping past the appropriate portions of memory. The power loss recovery process will transition the information in the state field of the new data objects having a WRITTEN_DATA state to a VALID_DATA state, and those original data objects having a VALID_DATA state to an INVALID_DATA state. In this manner, uncorrupted data can be guaranteed in the event a write operation is interrupted by power loss. Thus, in the worst case, a power failure during the updating of a data object results in the loss of the new data. The old data remains valid and can be recovered.
[0053] A reclamation process also uses the information of the state field to determine when a block of memory can be erased to reclaim memory, namely, when the state of the index table object or a data segment object is in the WRITING_HDR_LEN, WRITING_HDR, WRITTEN_HDR, WRITING_DATA, and INVALID_DATA states. A more detailed description of a reclamation process using the information of the state field is provided in commonly assigned, co-pending U.S. application Ser. No. ______, entitled “DATA OBJECT MANAGEMENT FOR A RANGE OF FLASH MEMORY,” to Wong et al., filed Aug. 29, 2002, which is incorporated herein by reference.
[0054] FIG. 4A shows the interrelationship between the index table object 403 , comprising index table 402 and index table header X-1 404 , and index table object 407 , comprising index table 406 and index table header Y-1 408 , respectively, and the data segment objects they index. FIG. 4A represents the storage of two separate multiple segment data objects, data object X and data object Y. Again, while the index table objects 403 and 407 are shown as having contiguously stored index tables 402 and 406 and index table headers 404 and 408 , this need not be the case in practice. Moreover, the index table objects 403 and 407 need not be contiguously stored with data segment objects they index, as will be further appreciated.
[0055] As shown in FIG. 4A , each data segment object, such as data segment object X-1-2 410 , is identified by a designation such as “MS X-1-2.” In this designation, X is the designation of the data object of which it is a part, the first numerical digit represents the index table key of index table object MST X-1 407 , and the second numerical digit represents the segment key, in this case signifying the data segment object is the second data segment object index within index table 402 .
[0056] For each data segment object making up part of each data object, there is an index entry in the index table 402 and 404 associated with index table object MST X-1 403 and MST Y-1 407 , respectively. More specifically, each index entry identifies the container object in which each data segment object is stored, and the data segment key for each data segment object in the index table 406 . For example, in the index table 402 , there are four index entries. The first index entry 412 references data segment object MS X-1-1 414 , the first data segment object indexed in the index table 402 and residing in container object 1 416 . The second index entry 418 references data segment object MS X-1-2 410 , the second data segment object indexed in the index table 402 and also residing in container object 1 416 . Index entry 420 similarly references MS data segment X-1-3 422 , and index entry 424 references MS data segment MS X-1-4 426 .
[0057] MS index table object MST Y-1 407 , comprising index table header 408 and index table 406 , heads a second MS data object. Index entries 430 , 432 , 434 , 436 reference MS data segment objects MS Y-1-1 438 , MS Y-1-2 440 , MS Y-1-3 442 , and MS Y-1-4 444 , respectively. As will be appreciated, the segment designations refer to the data object Y, the index table header 408 and index table 406 of data object Y, and the segment key for each of the data segment objects 438 , 440 , 442 , and 444 , within the index table. Entries in the index table 406 indicate the container objects 416 and 448 in which the data segment objects reside.
[0058] It will be appreciated that the structure of the multiple segment data objects allows for great flexibility in how the MS data objects actually are stored in memory. For example, data segment objects can be separated by other data segment objects of data, the way that data segment objects MS X-1-1 414 and MS X-1-2 410 are separated by SS data segment object 4 446 , or can be contiguously located, such as MS X-1-2 410 and MS X-1-3 422 . A data segment object can even be located after another MS index table object, the way that MS X-1-4 426 is located after MST Y-1 407 . Also, data segment objects in data object Y headed by MST Y-1 408 reside in two different linear object containers 416 and 448 . Data segment objects MS Y-1-1 438 and MS Y-1-2 440 reside in the first linear object container 416 , while MS data segment objects MS Y-1-3 442 and MS Y-1-4 44 reside in the second linear object container 448 . Storage of data segment objects is flexible using an embodiment of the present invention which, as shown in FIG. 4A , does not require that data segment objects be contiguously stored.
[0059] It will be appreciated that using embodiments of the present invention, the length of multiple segment data objects is flexible, and writing or updating data requires only rewriting of the affected index table object and the affected data segment objects. The length of the multiple segment data objects is flexible because index entries can be added to the index tables 402 and 406 for each data segment object added to each data object, updating the index table headers 404 and 408 , respectively, as necessary. If not enough space has been allocated for sufficient index entries to identify each of the data segment objects in the data object, a new index table object can be allocated and written elsewhere in the memory space. In any case, the index table objects are not a predefined tables with a fixed number of entries that would limit the number of segments that can be included. Similarly, the maximum length of the data objects is flexible, thus data objects are not restricted to a limited number of data segment objects. Also, writing or updating data, in addition to writing the data segment objects themselves, requires updating of only one index table object. The hierarchy of the described embodiment does not use a secondary group or sequence layer of tables, thereby saving time in updating tables as well as saving wear of degradable flash memory cells.
[0060] In the foregoing example of the present invention shown in FIG. 4A , only one index header table object was used to index all the data segment objects of each data object. It will be appreciated by one ordinarily skilled in the art that the index table objects could grow to be large, which could become a consideration when the index table object would have to be changed, reallocated, and rewritten. Accordingly, it may be desirable for larger data objects to have data segment objects indexed by a plurality of shorter index table objects, with new index table objects being allocated when an index table object reaches a certain predetermined length, or based on other considerations.
[0061] The present invention allows for this alternative type of data structure and storage. FIG. 4B shows a single data object stored according to an embodiment of the present invention, but this time the data object is indexed under more than one index table object. Specifically, instead of two data objects, X and Y, being stored, data object Z 450 is stored using two index table objects, index table objects Z-1 452 and Z-2 456 .
[0062] Index table object MST Z-1 452 , having index table header 453 and index table 454 , references data segment objects MS Z-1-1 460 , MS Z-1-2 461 , MS Z-1-3 462 , and MS Z-1-4 463 , which are referenced by index table entries 465 , 466 , 467 , and 468 , respectively. In addition, as part of the same data object, index table object MST Z-2 456 , having index table 457 and index table 458 , references data segment objects MS Z-2-1 470 , MS Z-2-2 471 , MS Z-2-3 472 , and MS Z-2-4 473 , which are referenced by index table entries 474 , 475 , 476 , and 477 , respectively. The data segment object designations reflect that the data segment objects are part of the same data objects, as indicated by the designation Z, but are referenced by different index table objects. Data segment objects MS Z-1-1 460 , MS Z-1-2 461 , MS Z-1-3 462 , and MS Z-1-4 463 all indicate they are referenced by index table object MST Z-1 452 because their first numerical digit references the first index table object. On the other hand, data segment objects MS Z-2-1 470 , MS Z-2-2 471 , MS Z-2-3 472 , and MS Z-2-4 473 all indicate they are referenced by index table object Z-2 456 because their first numerical digit references the second index table object.
[0063] Using separate index table objects can simplify the process of updating data objects. Because the data segment objects are referenced by different index table objects, if a change in data segment object MS Z-2-1 470 had to be changed, that segment would be updated and/or reallocated as required, and MST Z-2 456 would have to be updated as well. However, index table object MST Z-1 452 would not have to be changed to reflect the change, because the change was to a data segment object not referenced by another index table object. As one with ordinary skill in the art will appreciate, if this were a very lengthy data object with many data segment objects, only having to reallocate and/or revise one smaller index table object would be simpler than having to reallocate and or revise a very large single index table object used to reference all the data segment objects in the data object.
[0064] FIG. 5 shows the logical relationship between multiple index table objects 504 , 508 , and 512 in a data architecture in which data segment objects are stored using multiple index table objects. Each index table object, such as index table object 504 , has an index table header 506 and an index table 520 . Entries 524 in the index table 520 point to data segment objects 528 , which are designated MS Z-1-1 through MS Z-1-5. What FIG. 5 highlights is how the data segment objects of data object Z are linked through their respective index table objects 504 , 508 , and 512 into a single data object. More specifically, the NextIndexTableKey field 532 of the index table header 506 of index table object 504 references index table object 2 508 . In turn, the NextIndexTableKey field 540 of index table header 2 530 of index table object 2 508 in turn references a next index table object, index table object 3 (not shown). As many index table objects can be used as is desired, through index table object N 512 . In the last index table header N 512 , the NextIndexTableKey field would store a NULL value to indicate it is the last index table object in the data object. It will be appreciated that each of the data segment objects shown in FIG. 5 references Z as their data object, and, the index table object in which they are referenced.
[0065] The index table objects can be of different sizes. Because there is no requirement that the index table objects be of equivalent size, changes in the data object do not necessitate changes in all the index table objects. Also, whether using one or more index table objects to reference the data segment objects, the size of the data segment objects is variable and implementation specific.
[0066] From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. | A multiple segment data structure and method manage data objects stored in multiple segments. The structure and method use one or more multiple segment index table objects containing defining information about the data objects in which the data are stored, such as the state, index table size, and one or more index tables referencing the data segment objects. The data objects themselves comprise a header, specifying information about the data segment, including a data segment state, and a data section in which data actually are stored. The state fields in the index table object and the data segment objects facilitate the data recovery process. | 6 |
BACKGROUND
This invention relates to valve assemblies. It has particular application to valves which are used typically in relatively inaccessible locations, e.g. valves of the type which are used in subsea pipelines.
The components of valves, e.g. gate valves which are used in subsea locations, are subject to wear, corrosion and erosion and hence periodically need replacement. It has been proposed to mount the flow control components of such valves, typically the gates and seats, in an insert which can be removably mounted in a receiver receptacle. The receptacle can be coupled to the flow line which the valve controls. This enables the insert to be removed either by a diver or by a remotely operated vehicle for the replacement of the valve components. In such arrangements it is necessary to provide an adequate seal between the insert and the receiver. Known arrangements use inserts or receivers which are relatively complex to produce.
A type of insert valve is shown in the U.S. patent application Ser. No. 07/555,055, of David Garnham, filed July 19, 1990 and assigned to the same assignee as the present application. This application discloses a removable body portion carrying the flow controlling elements, a receptacle which receives the body and axially movable sealing members. The sealing members have metal seals positioned thereon for engagement with the body when it is inserted into the receptacle. Bifurcated levers are mounted on the sealing members and are contacted by the body upon insertion to urge the metal seals into contact with the face of the removable body portion.
The K. B. Bredtschneider et al. U.S. Pat. No. 3,179,121 discloses a ball valve construction with a ball and seats manually removable as a unit. The seats seal against the valve body with elastomeric seal means on a tapered surface.
The M. R. Jones U.S. Pat. No. 3,589,674 discloses another ball valve structure with a second pressure balancing stem in which the ball, seats and balance stems are manually removable as a unit.
The J. A. Burkhardt et al. U.S. Pat. No. 3,799,191 discloses a gate valve structure with a removable body containing the gate, seats, stem and stem operating means. The removable body is secured to the valve body by a lock ring.
The R. L. Ripert U.S. Pat. No. 4,387,735 discloses a valve structure removable from a pipeline wherein the valve is received within a support structure attached to the pipeline. The support structure has seal rings mounted therein which a worm gear mechanism activates into engagement with the removable valve structure to form a fluid tight conduit.
The R. L. Ripert U.S. Pat. No. 4,431,022 discloses a removable valve structure received within a support structure similar to that of the '735 patent. The valve structure has all components mounted therein, including a sealing means on each end of the valve which is biased outwardly to engage parallel plates on the support structure. A pressure responsive means for moving the seal rings inwardly during installation and removal is also disclosed.
The J. E. Lawson U.S. Pat. No. 4,874,008 discloses a valve mounting structure whereby hydraulic studs are used to secure a valve body between mounting members which are part of a block manifold used in oil and gas production.
SUMMARY
According to the present invention there is provided a valve arrangement comprising an insert assembly removably receivable in a receptacle, the insert assembly including valve elements for controlling fluid flow through a flow path in the insert assembly, the receptacle including a flow path which, when the insert assembly is received in the receptacle, communicates with the flow path in the insert assembly, the insert assembly including a gate and annular seat members disposed in the flow path therethrough, the arrangement being such that in operation when the insert assembly is located in the receptacle, movement of the gate against a seat member causes the seat member to be urged into sealing engagement with the gate and the receptacle body.
Preferably the gate is an expandable type gate and said seat member is urged into said sealing engagement by expanding said gate.
An object of the present invention is to provide a valve arrangement of the insert type which is relatively simple to manufacture.
Another object is to provide an insert type valve which can be easily installed and removed from its mounting receptacle.
A further object is to provide an insert type valve which is particularly adaptable to use in relatively inaccessible locations such as subsea oil and gas wells.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the present invention are set forth below and further made clear by reference to the drawings, wherein:
FIG. 1 is an elevation view in section of a valve assembly in accordance with the present invention.
FIG. 2 is an enlarged sectional view on the line 2--2 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings a valve assembly comprises a receptacle 10 which can receive a valve insert assembly 11. The receptacle 10 comprises a metallic block formed with a first bore 12 into which the insert 11 is designed to locate. The bore 12 is closed at its lower end. The bore 12 is generally cylindrical and has an upper portion 14 which is slightly wider than the lower portion 15. The wall of the upper bore portion 14 also tapers slightly outwardly towards its upper end. At diametrically opposite positions the wall of the upper bore portion 14 is formed with longitudinally extending recesses 16, 17 which are of generally rectangular cross-section. A second bore 20 extends through the receptacle 10 in a direction generally perpendicular to the axis of the first bore 12. The second bore 20 opens into the lower part of the upper bore portion 14. The recesses 16, 17 are dimensioned such that a flat surface is provided around each opening of the bore 20 at its junction with the bore 12. The longitudinal extent of each recess 16, 17 is from the upper end of the bore 12 to a position just below the bore 20. The second bore 20 constitutes a flow path for fluid such as oil flowing in a subsea flow line. Typically the receptacle 10 will be connected to such a flow line.
The upper part of the receptacle block 10 around the open end of the bore 12 has an outwardly extending annular flange 25. The upper surface of the block inwardly of the flange is formed with an annular groove 26.
The insert assembly has a body portion 30 which is generally cylindrical. An upper part 31 of the body 30 has a diameter which is slightly greater than the lower part 32. The lower part 32 is designed to locate in the lower bore portion 15 whilst the upper part locates in the upper bore portion 14. As can be seen in FIG. 2 diametrically opposite segmental portions 33, 34 of the upper body part 31 are cut away, these being located in juxtaposition with the recesses 16 and 17 of the receptacle 10. The body portion 30 is formed with a central through aperture 38 of rectangular cross-section, this aperture being arranged to receive an expanding type gate 40. The upper body part 31 is formed with tapped bores 39 which extend axially into the wall of the body portion 30 from the upper surface thereof. The bores are engaged by bolts 44 which couple the body 30 to a bonnet assembly 48.
The body 30 also has a lateral through bore 50 extending perpendicular to the longitudinal axis of the aperture 38. The bore 50 when the insert is in position in the receptacle is arranged so that it extends coaxially with the bore 20. Two annular seat members 52, 53 are carried by the body 30 at opposite end portions of the bore 50. The annular inner and outer end faces of each seat member carry metal seals 54 which are located in grooves in the seats.
The gate 40 is an expanding type gate which is coupled by an upwardly extending rod 55 Which extends through the bonnet 48 to an actuating mechanism (not shown.) The actuating mechanism can be operated to actuate the gate in a known manner. The gate comprises two juxtaposed parts 58, 59 which have matching inner engaging profiles 60, such that when one part is moved axially relative to the other the effective lateral dimension of the gate is varied. The two parts of the gate have a through bore 60 which can be aligned by axial movement of the gate with the bore 20. When the gate 40 is in the position shown in FIG. 1 it prevents flow through the flow line 20. When the gate is raised to bring the bore 60 into alignment with the flow line 20 the valve is open and fluid can flow through the valve.
The bonnet assembly 48 is formed with a shoulder 62 which in the assembled position is engaged by an annular clamping ring 65 which receivably engages the flange 25 to couple the bonnet assembly to the housing 10. The lower face of the bonnet has an annular groove 66 which aligned with the groove 26. A suitable seal is disposed in the aligned grooves.
In operation the valve body 30 is initially connected to the bonnet assembly 48 using the bolts 44. The gate 40 is arranged such that its lateral extent is at a minimum. The bonnet with the body 30 suspended from it is then lowered towards the receptacle 10. The body 30 is aligned such that the diametrically opposed flats on the body are at positions corresponding to those of the recesses 16 and 17 in the receptacle 10. The body 30 is then lowered into the bore 12 formed in the receptacle. As can be seen the outer dimensions of the body 30 are such that there is a small clearance between the body and the wall of the bore 30. Also with the gate in its condition of minimum lateral extent there is a clearance between the outer ends of the seat members 52, 53 and the wall of the bore 12 in the receptacle. When the body has been lowered to a position corresponding to that shown in FIG. 1 the gate is actuated such that its lateral extent is increased. This action places a relatively high load between the gate and the seat members 52, 53 which causes a metal-to-metal seal to be formed both between the gate body and seal 54 on the inner end of each member 52, 53 and between the receptacle body 10 and the seal 54 on the outer end of each seat member. The bonnet 48 is secured to the receptacle body 10 by the clamping ring 65. As will be seen the arrangement is relatively simple to assemble and operate and is also relatively simple to manufacture. The assembly can be carried out by a remotely operated vehicle or by a diver.
The arrangement shown in the drawings has a gate body 30 which is connected to a bonnet assembly 40 by means of the bolts 44. It will be appreciated that it is possible to manufacture an arrangement in which the body 30 and the bonnet assembly 48 are integral.
It will be appreciated that retrieval of the insert assembly is substantially the reverse of assembly procedure described above. The ring 65 is released and the gate is actuated to assume its minimum lateral dimension condition. The insert assembly can then be removed from the receptacle.
The invention has been described with reference to an expandable type gate which is the preferred arrangement. The insert assembly can also operate satisfactorily with a slab-type gate which is not expandable. When an insert containing a slab-type gate is located in its receptacle the upstream pressure on the gate will cause the gate to move laterally to such an extent that sealing will occur between the gate and seat and between the seat and receptacle body. | A valve arrangement having an insert assembly (11) receivable in a receptacle (10). The insert assembly includes valve elements for controlling fluid flow through the valve. These include a gate (40) and chamber valve seat members (52, 53). The insert is constructed so that it can be removed from and located in the receptacle. When located in the receptacle and in operation the gate is urged against one of the seat members so that a seal is formed between the seat and gate and between the seat and receptacle body. The gate (40) can be an expandable gate. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This nonprovisional application is a continuation of and claims priority to U.S. nonprovisional application Ser. No. 14/069,686, entitled “NMR RF Probe Coil Exhibiting Double Resonance”, filed Nov. 1, 2013, now U.S. Pat. No. 8,779,768, which is a continuation-in-part of and claims priority to U.S. nonprovisional application Ser. No. 13/916,231, entitled “NMR RF Probe Coil Exhibiting Double Resonance”, filed Jun. 12, 2013, which claims priority to provisional application No. 61/658,706, entitled “NMR RE Probe Coil Exhibiting Double Resonance”, filed Jun. 12, 2012, all of which are incorporated herein by reference in their entireties.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This invention was made with Government support under Grant No. 1R01EB009772-01 awarded by National Institute of Health. The government has certain rights in the invention.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates, generally, to nuclear magnetic resonance (NMR). More specifically, it relates to radiofrequency (RF) transmit-receive coils.
2. Brief Description of the Related Art
Nearly 50% of all the prescription drugs that are in use today were derived from naturally occurring chemicals, also called natural products. In order to identify natural products, they must be fully characterized using spectroscopy techniques such as nuclear magnetic resonance (NMR). NMR is unique in its ability to provide precise information about molecular structure and dynamics. Though NMR is quite powerful, its low sensitivity, however, is a major bottleneck in natural product discovery.
To gain maximum sensitivity, NMR spectrometers are designed to operate at high magnetic field strengths, and consequently the spectrum of NMR signals is in the radio frequency range. The transmit/receive coils are the probe coils that stimulate the nuclei and detect the NMR response from the sample. The sensitivity of the probe coils is primarily dependent on two factors the quality factor (Q-factor) of the coil and the filling factor of the coil. The Q-factor can be improved by constructing the coil out of low loss/resistance materials, such as high temperature superconducting (HTS) materials (Brey, W. W., Edison, A. S., Nast, R. E., Rocca, J. R., Saha, S., and Withers, R. S. (2006) Design, construction, and validation of a 1-mm triple-resonance high-temperature-superconducting probe for NMR, J Magn Reson 179, 290-293; Brey, W. W., Edison, A. S., Hooker, J., Nast, R. E., Ramaswamy, V., and Withers, R. S. (2012) Design, construction and validation of a High-Temperature-Superconducting 13 C optimized 1.5-mm cryogenically cooled NMR probe for natural products and metabolomics, In The 53 rd Experimental NMR Conference , Miami, Fla.).
The filling factor can be improved by placing the coil very close to the sample. In multi-channel NMR probes, therefore, the sensitivity of each channel decreases as the distance between coils and the sample increases. Thus, the sensitivity of the probes can be optimized at an inefficient rate of only one channel at a time, namely, the coil placed closest to the sample. Furthermore, another drawback of the probes and methodology of the prior art is that the placement of coils in very close proximity to each other causes undesirable interaction between them.
Another factor affecting sensitivity, aside from materials used (e.g., HTS) and proximity to the sample, is the size of the coil size. Smaller coil sizes tend to lead to more insensitive coils.
An NMR probe coil provides the radiofrequency (RF) magnetic field to the sample, thereby stimulating the nuclear spins, and detects the response of the nuclear spins. When RF current flows through the windings of the NMR probe coil, an RF magnetic field is produced perpendicular to the direction of the current. An RF transmit current forced into the coil produces an RF magnetic field in the sample region, which excites the nuclear spins. Conversely, the RF magnetic field caused by the precession motion of the nuclear spins induces an RF current in the coil windings. In the transmit mode, the strength of the magnetic field decays away with an increase in the distance from the coil, as determined by the Biot-Savart law. By reciprocity, in the receive mode, the strength of the induced current in the coil decays as the distance between sample and coil increases. Under these conditions, it is desirable to design the NMR probe coils to be placed as close as possible to the sample for purposes of optimizing sensitivity.
Another important factor affecting the performance of the RF probe coils is the Q-factor of the coil. The Q-factor can be improved by lowering the resistance and thus the loss in the material of the coil. This may be achieved by either lowering the temperature of the normal metal coils, or by using superconducting material. NMR probe coils are commonly fashioned out of HTS materials. This is achieved by patterning the HTS on planar dielectric substrates. However, such planar coils offer significant constraints to placing the coils very close to the sample.
For NMR excitation and detection of multiple channels, conventional RF probes utilize one (1) pair of coils for each channel. The pair of coils that is placed closest to the sample performs at its optimum to achieve excellent sensitivity. Each additional channel requires a pair of coils nested outside all the other channels. As channels are added, each additional pair of coils must be placed farther away from the sample, providing lower and lower sensitivity. An NMR field frequency lock channel typically used for analytical NMR requires its own coil pair in addition to the others. A typical “triple resonance” NMR probe of the type commonly used for biomolecular structure experiments requires a total of four (4) nested pairs of coils, and of these, only the inner pair is optimized for sensitivity since it is closest to the sample.
The prior art has attempted to improve upon NMR RF probe coils. For example, U.S. Pat. No. 4,973,908 relates to a surface coil for NMR spectroscopy of humans which utilizes a circular coil and a figure-8 or butterfly coil that is produces a magnetic field substantially perpendicular to the circular coil. The '908 patent applies to a surface coil rather than a volume coil, applies to human rather than analytical NMR spectroscopy, is fabricated from freestanding metal rather than deposited on a dielectric substrate, and relies on discrete rather than distributed and integrated capacitive elements to tune to the NMR frequency.
U.S. Pat. No. 4,816,765 describes a surface coil for MRI of human which utilizes coplanar coils of different shapes to generate orthogonal magnetic fields. The coils are intended for quadrature MRI applications.
U.S. Pat. No. 5,565,778 discloses a self-resonant structure known as a “racetrack” which incorporates interdigital capacitors into the NMR coil.
U.S. Pat. No. 5,594,342 describes dividing the current carrying elements into thin strips to avoid distortion of the NMR polarizing field.
U.S. Pat. No. 6,201,392 describes to a number of configurations of parallel superconductive coils to minimize interaction between coils. Simple rectangular coils are partly overlapped or otherwise disposed to null their mutual inductance. A parallel LC trap can be incorporated into the rectangular coil to reduce interaction with other coils at a single frequency. However, this prior art does not teach orthogonal magnetic fields as a means to null the mutual inductance between the coils. Rather, it teaches parallel magnetic fields over the sample region. Parallel magnetic fields have several drawbacks, however. For example, coil independence can be achieved only by requiring adjustment of overlap of coils on a single substrate and/or adjustment of the spacing of coils on independent substrates. Further, the '392 patent does not teach the use of fixed coupling loops which utilize variable capacitors to adjust tuning and matching.
U.S. Pat. No. 7,397,246 relates to methods for combining superconductive and low-Q coils such that the low-Q coils do not spoil the Q of the superconductive coils. The methods involve crossovers in the low-Q coils to reduce capacitive coupling to the superconductive coils.
U.S. Pat. No. 7,446,534 discloses a method to suppress the electric field of the NMR coil fringing into the sample.
U.S. Pat. No. 8,089,281 relates to doubly resonant surface coils with the magnetic fields substantially orthogonal to each other.
However, the foregoing prior art suffers from the one or more of the following disadvantages, despite the increased sensitivity seen in probes formed of HTS materials. Conventional probe coils have been unable to replace the industry standard 5-mm triple resonance probe used in laboratories. Probes that are newly developed tend to be niche probes that are capable of use in very specific applications. Additionally, there are moving elements with HTS probes that are not used in probes based on metal wires. These moveable wire loops adversely affect static magnetic field homogeneity, which makes initial adjustment difficult and reduces the resolution that can be obtained. The loops also can fail and are difficult to repair. Further, patterning multiple coils close to each other causes interference that can affect the reproducibility of results.
In a conventional NMR probe, metal wire or foil loops surrounding the sample convert a tiny RF magnetic field from the sample into electrical signals which are detected by the spectrometer. The conversion is not an efficient process because of the resistance of the metal. In an HTS probe, self-resonant coils are formed of thin-film oxide superconductors, such as yttrium barium copper oxide (YBCO), instead of metal. This is used as NMR detection coils because of their extremely high quality factors and nearly loss-free qualities in the NMR frequency range. The film is available as a coating on polished sapphire wafers. Electrical energy is coupled into and out of these coils by means of inductive coupling to a wire loop at the end of a coaxial transmission line. Mechanical adjustment of the position of the wire loop is used to adjust the coupling to match the coil impedance to the characteristic impedance of the transmission line. A related adjustment of radio frequency properties is known as tuning. Tuning refers to a shift in resonant frequency of the NMR coil. In HTS, this shift is accomplished by moving a shorted wire loop so that it intercepts a variable amount of flux from the NMR coil.
The moving loop approach for tuning and matching has some important disadvantages. Most importantly, moving a loop and coaxial cable close to the NMR sample tends to change the uniformity of the polarizing magnetic field. In NMR, chemical resolution is typically limited by the uniformity of the polarizing field. Great effort is made to adjust this uniformity in a process called “shimming.” Even if the loop is made from high quality susceptibility-compensated wire, the effect is noticeable. It is, therefore, not possible to adjust the RF coupling (known as matching) or the tuning without affecting the resolution, requiring a time-consuming step of re-shimming the magnet.
Another drawback of moving loops is basic to the use of moving parts in almost any device. Moving parts tend to be less reliable than other approaches, as there is higher chance of inefficiencies and failure.
Additionally, the number of nested pairs required for a triple resonance NMR probe places a limit on the sample diameter that can practically be accommodated. To achieve reasonable sensitivity and field homogeneity, each coil pair must be at least as wide as the gap between the coils. Within a “standard bore” NMR magnet, shim and pulsed field gradient coil, there is not enough room to nest more than about three (3) channels around a standard 5-mm diameter sample tube. There is very little space available in NMR probes, and the need for independent loops for the two functions makes the design, construction, adjustment and repair of HTS NMR probes significantly more difficult and time consuming. There is insufficient space to accommodate the coils required for a triple resonance probe that requires four (4) channels and four (4) nested pairs.
Accordingly, what is needed is an NMR probe that has multiple RF coils in close proximity with each other and with the sample, while producing a strong and homogenous magnetic field at both frequencies that reduces electric fields within the sample region and while also minimizing the interaction between the RF coils. With HTS materials, fewer superconducting materials should be needed, thus allowing for a larger, standard-sized sample, while eliminating moving parts, in turn improving reliability and reproducibility of results. However, in view of the art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the field of this invention how the shortcomings of the prior art could be overcome.
All referenced publications are incorporated herein by reference in their entirety. Furthermore, where a definition or use of a term in a reference, which is incorporated by reference herein, is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
While certain aspects of conventional technologies have been discussed to facilitate disclosure of the invention, applicants in no way disclaim these technical aspects, and it is contemplated that the claimed invention may encompass one or more of the conventional technical aspects discussed herein.
The present invention may address one or more of the problems and deficiencies of the prior art discussed above. However, it is contemplated that the invention may prove useful in addressing other problems and deficiencies in a number of technical areas. Therefore, the claimed invention should not necessarily be construed as limited to addressing any of the particular problems or deficiencies discussed herein.
In this specification, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned.
BRIEF SUMMARY OF THE INVENTION
The long-standing but heretofore unfulfilled need for a single coil NMR probe that can operate at two frequencies, while producing a strong and homogenous magnetic field at both frequencies that reduces electric fields within the sample region is now met by a new, useful, and nonobvious invention.
In an embodiment, the current invention is an NMR probe. The NMR probe includes a first RF coil and a second RF coil patterned on a dielectric substrate, and a pair of such dielectric substrates with a sample region therebetween configured to receive an NMR sample. The first and second RF coils are patterned on a single dielectric substrate, are formed of conductive materials, and generate magnetic fields that are each resonant with an operating frequency that may be the same or different. The magnetic fields of the first and second RF coils are orthogonal to each other at their respective operating frequencies in the sample region. With this structure and configuration, these magnetic fields excite and detect their respective NMR signals at their operating frequencies simultaneously.
The first and second RF coils can each include a set of current-carrying elements that are exclusive of each other at their respective radiofrequencies/operating frequencies. Alternatively, the current-carrying elements can be the same, such that resonances are produced from the current-carrying elements by differences in current density distribution at the operating frequencies.
Structurally, the RF coils can be configured in a variety of manners. The RF coils can be patterned on opposite sides of a single dielectric substrate. Optionally, a Faraday shield may be positioned between the radiofrequency coils, where said Faraday shield would shield the electric field generated by said second coil distal to the sample, but would not affect the magnetic field generated by said first RF coil proximal to the sample. Further, the first and second RF coils can be a spiral coil and a figure-8 racetrack resonator, respectively. In this embodiment, the spiral coil may generate its magnetic field substantially perpendicular to the plane of the dielectric substrate, and the figure-8 racetrack resonator may generate its magnetic field substantially parallel to the plane of the dielectric substrate. Here, the figure-8 racetrack resonator coils on either side of the sample may carry current in counter directions so that the generated magnetic fields are additive and parallel to the plane of the dielectric substrate.
Alternatively, the configuration can be such that the dielectric substrate is formed of multiple substrates that are fastened together. In this case, the RF coils would be patterned on the two different dielectric substrates.
Alternatively, the configuration can be such that the RF coils are patterned on the same side of the dielectric substrate in a manner that one RF coil is patterned within the other RF coil. Here, the first and second RE coils can be a spiral coil and a racetrack resonator, respectively, with the racetrack resonator positioned within the spiral coil. In this embodiment, the spiral coil may generate its magnetic field substantially perpendicular to the plane of the dielectric substrate, and the racetrack resonator may generate its magnetic field substantially parallel to the plane of the dielectric substrate.
The NMR probe may further include capacitive coupling between current-carrying elements of each RF coil across the dielectric substrate at either or both of the operating frequencies.
The NMR probe may further include inventive RF coils in the shape of a figure-8. The current in the probe at the operating frequencies would flow through the central conductor of the figure-8, such that the magnetic fields generated by the coils would be substantially parallel to the plane of the dielectric substrate. Further, the central conductor can have ends that are tapered (i.e., wider in the middle than at the ends) in order to improve homogeneity of the magnetic fields.
The NMR probe may further include a fixed inductive coupling loop for transferring energy into and out of the RF coils. The coupling loops would be terminated by a network of capacitors that are adjustable to achieve tuning and coupling of the RF coils. The coupling loops may be formed of non-superconductive metallic conductors (i.e., normal metallic conductors) or high temperature superconductors, among other suitable materials.
In a separate embodiment, the current invention is an NMR probe. The NMR probe includes a pair of dielectric substrates each comprising a spiral coil and a figure-8 racetrack coil, a sample region therebetween configured to receive an NMR sample, capacitive coupling between the current-carrying elements of the coils, and a fixed inductive coupling loop. The RF coils are patterned on a single dielectric substrate, are formed of conductive materials, and generate magnetic fields that are each resonant with an operating frequency that may be the same or different. The magnetic fields of the RF coils are orthogonal to each other at their respective operating frequencies in the sample region. The current-carrying elements of the coils are exclusive of each other at their respective radiofrequencies/operating frequencies. Structurally, the spiral coil is patterned on one side of the dielectric substrate, and the figure-8 racetrack resonator is patterned on the opposite side of the dielectric substrate. The figure-8 racetrack coils on either side of the sample carry current in counter directions so that the generated magnetic fields are additive and parallel to the plane of the dielectric substrate. A Faraday shield is positioned between the spiral RF coils, where said Faraday shield would shield the electric field generated by the spiral coil distal to the sample, but not affect the magnetic field generated by said racetrack coil proximal to the sample. As discussed, the NMR probe includes capacitive coupling between current-carrying elements of each RF coil across the dielectric substrate at either or both of the operating frequencies. The figure-8 racetrack coil comprises a central conductor patterned along the longitudinal axes of the RF coils. The current in the figure-8 coil at the operating frequencies would flow through the central conductor, such that the magnetic fields generated by the coils would be substantially parallel to the plane of the dielectric substrate. Further, the central conductor can have ends that are tapered (i.e., wider in the middle than at the ends) in order to improve homogeneity of the magnetic fields. The fixed inductive coupling loop is formed of high temperature superconductors and transfers energy into and out of the RF The coupling loops would be terminated by a network of capacitors that are adjustable to achieve tuning and coupling of the RF coils. With this structure and configuration, these magnetic fields excite and detect their respective NMR signals at their operating frequencies simultaneously.
In a separate embodiment, the current invention is a method of minimizing interaction between two (2) coils positioned in close proximity to each other. The two coils are patterned on a single dielectric substrate, and each generates its own magnetic field resonant at an operating frequency. The coils are positioned such that the magnetic fields are orthogonal to each other at their respective operating frequencies. With this methodology, the net magnetic flux generated by one coil and flowing through the other coil would be zero (0).
These and other important objects, advantages, and features of the invention will become clear as this disclosure proceeds.
The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts that will be exemplified in the disclosure set forth hereinafter and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which:
FIG. 1A is a perspective view of a coil according the prior art.
FIG. 1B is a perspective view of a single channel HTS probe according to the prior art
FIG. 1C is a cross-sectional layout of a 4-channel probe showing four (4) pairs of conventional HTS coils, according to the prior art.
FIG. 2A is a rear view of a 13 C- 1 H coil according to an embodiment of the current invention.
FIG. 2B is a front view of the 13 C- 1 H coil of FIG. 2A .
FIG. 2C is a cross-sectional layout of a 4-channel probe using double-resonance HTS coils according to the current invention. It can be seen that the number of elements in the probe can be cut in half with the use of double-resonance coils.
FIG. 3 depicts a 15 N- 2 H coil according to an embodiment of the current invention.
FIG. 4 is a mechanism for coupling electrical energy into and out of the self-resonant RF coils, according to an embodiment of the current invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part thereof, and within which are shown by way of illustration specific embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention.
In an embodiment, the current invention is an NMR RF probe coil that includes two NMR sample coils on a single substrate to allow better sensitivity for the second channel. Each RF coil is formed of conductive material patterned on a single dielectric substrate. The two sets of coils thrm a sample region between them for positioning the NMR sample. The coils can be used in existing NMR RF probes. These probes are used for chemical identification and structural analysis of molecules.
Using this NMR RF probe coil, two NMR coils can be placed in proximity to the NMR sample instead of one as in the conventional art. In an embodiment, the NMR RF probe coil includes superconductive oxide coils patterned on a flat dielectric substrate. Sensitivity and other performance aspects are improved for the second coil, which can be used for a second nuclear isotope. For example, the two nuclear isotopes can be and 13 C analyzed simultaneously. The novel arrangement and coil structures produce a uniform magnetic field over the sample space and resonate at the required radiofrequencies.
The probe coil is structured reduces the space required for the coils, allowing for larger samples in standard NMR magnets. This structure would permit function of a standard 4-resonance probe ( 1 H, 13 C, 2 H, 15 N) for a standard 5-mm diameter sample tube in a standard diameter magnet. Contrastingly, the conventional art has taught that high sensitivity superconductive probes are limited to smaller samples or fewer channels. With two coils on a single substrate, the number of coils in each probe is reduced by 50%, reducing complexity and cost.
In a contemplated arrangement of the probe coil, each coil set at one of the two resonance frequencies are exclusive of the current-carrying elements at the other frequency. The coils can be placed on the dielectric substrate in a variety of configurations. One configuration includes the coils placed on opposite sides of one dielectric substrate. Another configuration includes the coils patterned on two separate dielectric substrates that are fastened together. Another configuration includes the coils placed on the same side of one dielectric substrate, where one coil is placed within the other coil.
In an alternative arrangement of the probe coil, the current-carrying elements are not exclusive of each other at the two resonance frequencies. Capacitive coupling can be achieved between the two coils across the substrate at one or both of the two frequencies.
In an alternative arrangement of the probe coil, the NMR probe can comprise the current-carrying elements of each coil set at two frequencies that are the same. Two resonances can then be produced due to differences in the distribution of current density at the two frequencies.
In certain embodiments, the current invention further contemplates a method of using two RF coils in close proximity to one another with very little interaction. The two coils are positioned such that the net magnetic flux generated by one coil and flowing through the other coil is zero (0). As a result of this structure and positioning, the magnetic field produced by one coil at its operating frequency is orthogonal to the magnetic field produced by the other coil. The NMR probe coil includes conductive elements patterned on a dielectric substrate for a resonant device. The current in the coil at the resonance frequency flows through a central conductor, and flows back in the reverse direction through distal conductors. This creates a magnetic field within a sample region that is parallel to the dielectric substrate.
The central conductor may be wide near the middle of its structure and tapered along the ends along the longitudinal axis of the coil. This structure can help improve the homogeneity of the magnetic field of the NMR probe coil.
A single fixed loop can be used to couple electrical energy into and out of the HTS NMR coils. The loop is terminated by a network of trimmer capacitors that are adjusted to vary both the coupling and the resonant frequency of the NMR coil. This single fixed loop replaces two loops used in the prior art.
In order to allow for adjustments to tuning and matching, the single loop is in an over coupled condition to the NMR coil. This means that the impedance at the loop terminals looking toward the coil at the coil resonance frequency is less than the characteristic impedance of the transmission line. The amount of coupling needed can be predetermined and preset based on the inductance and quality factor of the NMR coil, the tuning range needed, and the anticipated loss in the NMR sample itself.
Further, electrical loss should be minimized in the fixed coupling loop. This electrical loss can occur as a function of two processes. First, there may be electrical loss due to the desired currents induced along the length of the coupling loop needed for coupling and tuning. These loops increase proportionally with the series resistance of the wire. In the typical limit for RF circuits, where the wire thickness is much greater than the skin depth, the series resistance varies inversely with the wire radius. This transport loss is then inversely proportional to wire radius, so it would be desirable to use a wire of large radius. However, magnetic flux perpendicular to the finite surface area of the wire induces so-called eddy currents in the wire, also contributing to electrical loss. A wire of larger radius would be subject to greater eddy current loss. As such, there is an optimal wire radius which can be determined for each case. The location and shape of the fixed coupling loop can also be adjusted to maximize coupling while minimizing eddy current loss. Because the loop is fixed, the wire would remain in the configuration of minimum loss at all times.
In certain embodiments, the current invention teaches doubly resonant coils that generate strong and homogenous magnetic field at two resonance frequencies. The current distribution in these two resonance modes is such that the magnetic fields within the sample region are orthogonal to each other. In an embodiment, a set of two coils whose magnetic fields are orthogonal to each other within the sample region is used to excite and detect the two resonance frequencies, thereby allowing for independent design optimization with almost negligible interaction between the two coils. In another embodiment, quadrature detection of NMR signal at one frequency may be achieved by positioning two coils that operate at the same frequency.
Conventional NMR probe coils, such as those seen in FIGS. 1A-1C known in the prior art and operating at their fundamental resonance frequency, generate a magnetic field perpendicular to the substrate of the coil. The pair of coils straddling the sample on either side forms a Helmholtz pair, and the magnetic field homogeneity is determined by the Helmholtz condition. FIG. 1B illustrates the arrangement of a single channel HTS probe: a pair of self-resonant HTS coils mounted on a coldhead, an inductive loop for coupling the RF energy from the coil, and another loop for frequency fine-tuning. Each additional channel requires the use of another set of coils and loops. The most useful configuration of NMR probe is known as ‘triple resonance’ because it includes channels for three of the most biologically significant elements: hydrogen, carbon and nitrogen. A fourth channel (deuterium) is included to regulate the magnetic field. An HTS probe of this nature requires the use of four pairs of coils as shown in FIG. 1C , along with the associated tuning and coupling loops.
Contrastingly, the current invention is a double-resonance probe coil that produces a strong and homogenous magnetic field at two frequencies simultaneously. The double-resonance coils provide optimum NMR detection sensitivity of both carbon and hydrogen as shown in FIG. 2C . They are superior to single-resonance designs because they allow ideal sensitivity of two channels simultaneously. Also, they reduce the expense and the complexity by reducing the number of coil pairs required.
In an embodiment, the present invention is an NMR coil that generates a magnetic field parallel to the substrate of the coil. The pair of coils on either side of the sample carries currents in counter directions, in order that the magnetic fields from both coils are additive. The homogeneity of the magnetic field can be optimized by adjusting the width and shape of the central conducting strip.
The presence of electric field within the sample region can be a source of loss in NMR experiments. In the design of NMR probes, it may be desirable that the coils have the lowest possible electric field in the sample region, so as to achieve high sensitivity. Various means of reducing the electric field are known in the art. In an embodiment of the invention, the coil used to generate the magnetic field at one of the frequencies can be used as a mechanism to shield the electric field at the other frequency. In a further embodiment, dedicated electric field shields are used to reduce the electric field penetrating the sample region.
It will be appreciated by those skilled in the art that a number of variations are possible within the spirit and scope of the invention. The scope of the invention should not be limited by the specific examples given, but by the appended claims.
Example 1
FIGS. 2A and 2B illustrate an embodiment of the current invention, a 13 C- 1 H coil generally denoted by the reference numeral 11 , where coil structures 10 , 14 are placed on opposite sides of one dielectric substrate. Exemplary coil 11 would be appropriate to use as the inner coil pair in an NMR probe designed for detection of both 13 C and 1 H isotopes. In this embodiment, a dielectric substrate (not shown) separates two superconductive films patterned into self-resonant coil structures 10 , 14 . Two such films are disposed around a cylindrical sample as in the prior art to produce a uniform RF magnetic field across the sample. The long axis of coil 11 would be oriented along the field axis of the solenoidal NMR magnet.
The aspect of coil 11 distal to the sample can be seen in FIG. 2A and is patterned into spiral coil structure 10 . Spiral coil structure 10 produces a field that is substantially perpendicular to the plane of the dielectric substrate. Spiral coil structure 10 is well suited to achieving low resonance frequencies associated with 11 C, 15 N and other nuclei, excluding 1 H and 19 F. However, the electric field of spiral coil structure 10 fringes away from the dielectric substrate and into the sample under analysis. The conductivity and dielectric loss of the sample are often enough to reduce the Q-factor of the coil and to contribute to the noise of the NMR measurement.
Thus, to improve sensitivity on the 13 C channel, coil 11 includes Faraday shield 12 on the aspect of coil 11 proximal to the sample as described in U.S. Pat. No. 7,446,534, which is incorporated herein by reference. Shield 12 includes thin, closely spaced wires that do not greatly affect the magnetic field produced by spiral coil structure 10 . The high frequency (typically 1 H) resonator is patterned on the “front” side of each dielectric substrate, facing the sample, as seen in FIG. 2B .
The building block for the 1 H coil is the “racetrack” resonator as described in U.S. Pat. No. 5,565,778, which is incorporated herein by reference. Two racetrack resonators 14 are patterned adjacent to each other. The resulting structure resembles the figure-8 coil described in U.S. Pat. No. 4,973,908, which also is incorporated herein by reference. Racetrack resonators 14 produce an RF magnetic field that is substantially parallel to the dielectric substrate and orthogonal to the electric field produced by spiral coil structure 10 on the rear side of the substrate.
Racetrack resonator 14 can be readily tuned to the higher frequency of the 1 H isotope. When broken with several gaps 16 , in this case with four (4) gaps, racetrack resonator 14 has a low fringing electric field and is suitable for use close to a biomolecular sample. Both spiral coil structure 10 and racetrack resonator 14 should be patterned into thin parallel wires as taught in U.S. Pat. No. 5,565,778 patent to reduce distortions of the polarizing magnetic field. Therefore, in areas where spiral coil structure 10 and gaps 16 overlap, where it is not possible to continue Faraday shield 12 , racetrack resonator 14 itself serves as a Faraday shield for spiral coil structure 10 and does not greatly affect the magnetic field of spiral coil structure 10 .
In NMR spectroscopy, it is important to produce a uniform RE magnetic field over the sample. The field of the figure-8 coil formed by adjacent racetrack resonators 14 is not as uniform, in general, as that of the pair of rectangular resonators. However, the uniformity can be improved by widening the central region of center portion 18 of the figure-8 coil. It may be advantageous for RE homogeneity to taper center portion 18 at the ends as shown in FIG. 2B .
Example 2
FIG. 3 illustrates another embodiment of the current invention, a 15 N- 2 H coil generally denoted by the reference numeral 21 , where the coil structures 22 , 24 are positioned on the same side of one dielectric substrate and one coil is placed within the other coil. Exemplary coil 21 would be appropriate to use as the outer coil pair in an NMR probe designed for decoupling on the 15 N channel and for engaging a 2 H field frequency lock. In this embodiment, both self-resonant coil structures 22 , 24 are patterned on the same side of the dielectric substrate, thereby eliminating the two-sided patterning of the HTS coils.
The longitudinal axis of coil 21 would be oriented along the field axis of the solenoidal NMR magnet. Coil 21 includes figure-8 coil structure 22 tuned to the 2 H frequency and spiral coil structure 24 tuned to the 15 N frequency. The magnetic field in the sample region at the spiral coil structure resonance frequency is substantially perpendicular to the dielectric substrate, whereas the magnetic field in the sample region at the resonance frequency of coil structure 22 is substantially parallel to the dielectric substrate. The central region of the center portion 18 of figure-8 coil structure 22 is widened to provide better RF homogeneity.
FIG. 4 illustrates a mechanism according to an embodiment of the current invention for coupling electrical energy into and out of the self-resonant RF coils or HTS NMR coils. Single fixed loop 30 is positioned in the probe such that it is inductively coupled to the RF coils. Loop 30 would be positioned in proximity to the resonant coil. Single fixed loop 30 replaces the moving tuning and coupling loops for a coil pair in the conventional art. Thus, a network of trimmer capacitors 32 , 34 are included to terminate loop 30 . Trimmer capacitors 32 , 34 are adjusted to vary both the coupling and the resonant frequency of the NMR coil. Adjusting trimmer capacitors 32 , 34 does not affect the resolution of the probe, requiring re-shimming each time the tuning and coupling are adjusted. The parallel capacitor 32 can be varied to tune the frequency of the self-resonant coil. The series capacitor 34 can be adjusted to match the coil impedance to the impedance of the transmission line 36 . Tuning rods (not seen) can be added to access the variable capacitors.
In order to allow for adjustments to tuning and matching, single loop 30 is in an over coupled condition to the NMR coil. This means that the impedance at the terminals of loop 30 looking toward the coil at the coil resonance frequency is less than the characteristic impedance of the transmission line. The amount of coupling needed can be predetermined and preset based on the inductance and quality factor of the NMR coil, the tuning range needed, and the anticipated loss in the NMR sample itself.
Further, electrical loss should be minimized in fixed coupling loop 30 . This electrical loss can occur as a function of two processes. First, there may be electrical loss due to the desired currents induced along the length of coupling loop 30 needed for coupling and tuning. These loops increase proportionally with the series resistance of the wire. In the typical limit for RF circuits, where the wire thickness is much greater than the skin depth, the series resistance varies inversely with the wire radius. This transport loss is then inversely proportional to wire radius, so it would be desirable to use a wire of large radius. However, magnetic flux perpendicular to the finite surface area of the wire induces so-called eddy currents in the wire, also contributing to electrical loss. A wire of larger radius would be subject to greater eddy current loss. As such, there is an optimal wire radius which can be determined for each case. The location and shape of the fixed coupling loop can also be adjusted to maximize coupling while minimizing eddy current loss. Because loop 30 is fixed, the wire would remain in the configuration of minimum loss at all times.
All referenced publications are incorporated herein by reference in their entirety. Furthermore, where a definition or use of a term in a reference, which is incorporated by reference herein, is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
The advantages set forth above, and those made apparent from the foregoing description, are efficiently attained. Since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention that, as a matter of language, might be said to fall therebetween.
Glossary of Claim Terms
Capacitance: This term is used herein to refer to the ability of a body to store an electrical charge
Capacitive coupling: This term is used herein to refer to the transfer of energy within an electric network by means of capacitance between circuit nodes.
Central conductor: This term is used herein to refer to an object or substance that allows heat, electricity, light or sound to pass along it or through it. Central means it is in or towards the center of the body.
Current-carrying elements: This term is used herein to refer to an aspect of an NMR RF coil that is structured for the flow of a current.
Dieletric substrate: This term is used herein to refer to electrical insulators, such as silicon, ceramic quartz, etc. It is selected with dielectric strength, dielectric constant and loss tailored for specific circuit application in order to serve as a base for another material. Generally, it is a nonconductor of electricity with electrical conductivity of less than a millionth (10 −6 ) of a siemens.
Magnetic flux: This term is used herein to refer to the component of the magnetic B field that passes through a surface. A lower magnetic flux corresponds to a lower interaction between magnetic fields generated by separate coils (i.e., the magnetic field generated by a coil is not passing through the surface of another coil).
Nuclear magnetic resonance: This term is used herein to refer to a physical phenomenon in which magnetic nuclei in a magnetic field absorb and re-emit electromagnetic radiation. The energy that is re-emitted is at a specific resonance frequency which depends on the strength of the magnetic field and magnetic properties of the isotope of the atoms.
Nuclear magnetic resonance probe: This term is used herein to refer to the portion of an NMR spectrometer responsible for a significant portion of the work. The probe is placed in the center of the magnetic field, and the sample is inserted into the center of the probe. The probe contains radiofrequency coils (RF) tuned at specific frequencies for specific nuclei.
Orthogonal: This term is used herein to refer to objects being perpendicular, non-overlapping, varying independently, or uncorrelated.
Parallel: This term is used herein to refer to two or more straight coplanar lines that do not intersect.
Perpendicular: This term is used herein to refer to two structures or aspects intersecting or forming a 90 degree (right) angle.
Radiofrequency coil: This term is used herein to refer to coils contained within the probe tuned at specific frequencies for specific nuclei.
Resonance: This term is used herein to refer to the tendency of a system to oscillate at varying amplitude at some frequency. The level of amplitude is greater at some frequencies than others. | NMR probe coils designed to operate at two different frequencies, producing a strong and homogenous magnetic field at both the frequencies. This single coil, placed close to the sample, provides a method to optimize the NMR detection sensitivity of two different channels. In addition, the present invention describes a coil that generates a magnetic field that is parallel to the substrate of the coil as opposed to perpendicular as seen in the prior art. The present invention isolates coils from each other even when placed in close proximity to each other. A method to reduce the presence of electric field within the sample region is also considered. Further, the invention describes a method to adjust the radio-frequency tuning and coupling of the NMR probe coils. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application Nos. 60/579,947 filed Jun. 15, 2004 and 60/579/369 filed Jun. 14, 2004, assigned to the assignee of this application and incorporated by reference herein. The subject matter of International Application No. ______, filed Jun. 10, 2005 and entitled “LOW-COST HEARING TESTING SYSTEM AND METHOD OF COLLECTING USER INFORMATION,” assigned to the assignee of this application and incorporated by reference herein, is related to this application.
FIELD OF THE INVENTION
[0002] The present invention relates to hearing testing systems, and more particularly, administering a hearing test on a low-cost system based on a toll-free telephone number or an Internet Web site. The inventive systems are programmed with a set of hearing test modules (frequencies at various amplitudes or with questions regarding issues that affect hearing or speech intelligibility), along with verbal or text instructions, which guide the person being tested to other hearing test modules based upon the user's response to the current hearing test module. In so doing, the user ends up in a pre-professional hearing test that then automatically guides the user to take a related action based upon the test results, for example, to seek further professional testing.
[0003] The present invention also relates to a method of collecting and storing user profile and hearing condition information. More particularly, the present invention relates to method of conveniently locating an automatic hearing testing system with a local database that captures user information and subsequently updates the user information onto a central database that can be used for marketing purposes.
BACKGROUND OF THE INVENTION
[0004] More than 25 million Americans have hearing loss, including one out of four people older than 65. Hearing loss may come from infections, strokes, head injuries, some medicines, tumors, other medical problems, or even excessive earwax. It can also result from repeated exposure to very loud noise, such as music, power tools, or jet engines. Changes in the way the ear works as a person ages can also affect hearing.
[0005] For most people who have a hearing loss, there are ways to correct or compensate for the problem. If an individual has trouble hearing, that individual can visit a doctor or hearing health care professional to find out if he or she has a hearing loss and, if so, to determine a remedy. The U.S. Food and Drug Administration (FDA) and similar governing bodies in other countries have rules to ensure that treatments for hearing loss—medicines, hearing aids, and other medical devices—are tried and tested.
[0006] However, most people do not even know that they have a hearing loss. Typical indications that an individual has hearing loss include: (1) shouting when talking to others, (2) needing the TV or radio turned up louder than other people do, (3) often having to ask people to repeat what they say because the individual can't quite hear them, especially in groups or when there is background noise, (4) not being able to hear a noise when not facing the direction it's coming from, (5) seeming to hear better out of one ear than the other, (6) having to strain to hear, (7) hearing a persistent hissing or ringing background noise, and (8) not being able to hear a dripping faucet or the high notes of a violin. If an individual experiences one of more of the above indications, the individual should see his or her doctor or hearing health care professional for further testing for potential hearing loss.
[0007] To find out what kind of hearing loss the individual has and whether all the parts of the individual's ear are functioning, the person's doctor may want him or her to take a hearing test. A health care professional that specializes in hearing, such as an audiologist, often gives these tests. Audiologists are usually not medical doctors, but they are trained to give hearing tests and interpret the results. Hearing tests are painless.
[0008] If the hearing test shows that the individual has a hearing loss, there may be one or more ways to treat it. Possible treatments include medication, surgery, or a hearing aid. Hearing aids can usually help hearing loss that involves damage to the inner ear. This type of hearing loss is common in older people as part of the aging process. However, younger people can also have hearing loss from infections or repeated exposure to loud noises.
[0009] In a well-known method of testing hearing loss in individuals, the threshold of the individual's hearing is typically measured using a calibrated sound-stimulus-producing device and calibrated headphones. The measurement of the threshold of hearing takes place in an isolated sound room, usually a room where there is very little audible ambient noise. The sound-stimulus-producing device and the calibrated headphones used in the testing are known as an audiometer.
[0010] A professional audiologist performs a professional hearing test by using the audiometer to generate pure tones at various frequencies between 125 Hz and 12,000 Hz that are representative of a variety of frequency bands. These tones are transmitted through the headphones of the audiometer to the individual being tested. The intensity or volume of the pure tones is varied until the individual can just barely detect the presence of the tone. For each pure tone, the intensity at which the individual can just barely detect the presence of the tone is known as the individual's air conduction threshold of hearing. Although the threshold of hearing is only one element among several that characterizes an individual's hearing loss, it is the predominant measure traditionally used to acoustically fit a hearing compensation device.
[0011] Known audiometers are of two main types: the manual and the “automatic” type. In the manual system for and method of testing hearing, a skilled operator adjusts the audiometer controls, thereby sending a plurality of audio signals through either earphones, loudspeakers, or bone vibrators to a subject sitting in a quiet room. The subject is requested to signal to the operator, by activating a switch connected to a pilot light, by raising a hand, or by any other visible or audible means, whenever he or she has heard the sound being sent. The operator watches for the subject's responses, interprets them, and translates them into written information on a chart. This information is represented by a graph called an audiogram, which represents the threshold of hearing of the subject for a plurality of audio frequencies.
[0012] In the automatic method known as the Bekesy method of hearing testing, the audiometer presents automatically changing tone frequencies to the subject while the intensity of the signal is controlled by the subject by means of a pushbutton switch activating a motor controlling the motion of an intensity attenuator. The subject's responses are also automatically recorded by a writing pen moving over a chart as the test progresses. While the Bekesy method was considered by those skilled in the art of audiology to be a major advance, it still requires the presence of a skilled operator and the use of rather sophisticated mechanical systems. Since the introduction of the Bekesy method, an automatic method of hearing testing has been proposed in U.S. Pat. No. 4,107,465, that dispenses with the need for a skilled operator and the use of rather sophisticated mechanical systems.
[0013] Although the professional test is complete and allows for a thorough diagnostic, most hearing-impaired individuals are not even aware that they are in need of a hearing test, even if some of the aforementioned symptoms exist. What is required is a way to recognize early onset of hearing loss without the need to visit the audiologist.
[0014] Indeed, there are some new methods for testing hearing loss, albeit at a less professional level, such as programs available on the Internet. To use such a program, a user logs onto a free hearing test Web site, adjusts his or her computer speaker volume to a supplied test frequency, and uses a mouse to click on various hyperlinks on a Web page on which the user can listen to various tones and determine how many tones he or she is able to hear. The user then is guided to instructional and “next step” pages. There are a number of problems associated with this method. First, most people that have hearing loss are older, and the Internet may truly not be accessible because of their level of use of technology. Second, many low-income families cannot afford computers to run the Internet programs. Lastly, this system does not “pull” users to the site; an individual has to know both that he or she wants to be tested and that a site like this exists (i.e., from advertisements). No business entity could afford to mass market such a site. Therefore, even though some low-cost non-professional hearing tests are available, there exists a need for an improved means for hearing tests that is more accessible and can be driven in the market to reach and test more people.
[0015] “LOW-COST HEARING TESTING SYSTEM AND METHOD OF COLLECTING USER INFORMATION”, International Application PCT/US2005/______, filed Jun. 10, 2005, claiming priority of U.S. Provisional Application No. 60/579,369, filed Jun. 14, 2004, incorporated by reference herein and assigned to the assignee of this application, describes a hearing testing system that can be administered through a standard low-cost data storage media, such as a CD, that is easily mass-marketed as a give-away and is easily used by the mass market. However, a conventional CD has a 700 MB storage limit, thereby restricting the complexity of the hearing test that can be administered through it. Moreover, mechanisms to further broaden the market reach of the hearing test are highly beneficial, as the easier it is for an individual to access a hearing test, the higher the likelihood that he or she will take the test. Therefore, what is needed is an improved way of conducting hearing tests that may be more complex than hearing tests that are administered through a CD, and that can be easily accessible to the mass market of individuals in order to reach and test more people.
[0016] Another problem with current methods for testing hearing loss is the inability to store user-specific information in a database and provide clear step-by-step guidance on the actions needed to find a solution once a hearing loss problem is detected. In the case of the Internet hearing test Web site previously described, the results of the test are not directed to another step, nor are they available to another entity, i.e., an audiologist. Therefore, an audiologist must retest the same frequencies and re-question the patient. Thus, there exists a need to streamline the testing process so that low-cost non-professional hearing tests lead to a more professional hearing test.
[0017] Another problem with both conventional non-professional hearing tests and the audiologist-administered professional hearing test is that the tests are simple frequency versus amplitude tests and do not take into account speech intelligibility issues. For example, even though an individual may have some hearing loss, he or she may be able to function quite normally, whereas others may have limitations in understanding certain spoken words. Thus, there exists a need to address some of these speech intelligibility issues.
[0018] Another problem with current testing methods is that the individual being tested has no idea at the hearing test what having a hearing aid would do to improve his or her quality of life. That is, even if the patient in either the non-professional test or the professional test recognizes hearing loss, the patient has no idea what the improvement would be if a corrective hearing aid were used. Thus, the motivation to get the problem fixed is much less than if the individual could experience the benefits of correction at the time of the test.
SUMMARY OF THE INVENTION
[0019] It is therefore an object of this invention to find a way for the mass market of individuals with potential hearing loss to recognize early onset of hearing loss without the need to visit an audiologist.
[0020] Another object of this invention is to develop an improved way of conducting hearing tests that may be more complex than hearing tests that are administered through a CD, and that can be easily accessible to the mass market of individuals in order to reach and test more people.
[0021] Another object of this invention is to streamline the testing process so that low-cost non-professional hearing tests lead to a more professional hearing test.
[0022] Another object of this invention is to address speech intelligibility issues at some level in hearing aid tests.
[0023] Another object of this invention is to show patients what the result of having a hearing aid would do to improve their quality of life, in order to improve the patients' motivation to fix the problem.
[0024] It is another object of the present invention to provide step-by-step guidance on the next steps to be taken once a hearing loss is detected.
[0025] The present invention provides for a hearing test stored on a centrally located computer that is accessible either by placing a toll-free call through a telephone using the telephone's microphone and/or keypad as an input device, or by establishing an Internet connection to a centrally located computer through a Web site. Both access methods are easily mass-market-able. In the present invention, the user can be led to the system by advertisement or by a low-cost CD hearing test system. This would allow the mass market of individuals with potential hearing loss to recognize early onset of hearing loss without the need to visit the audiologist. The present invention streamlines and connects low-cost, non-professional hearing tests to a more professional hearing test by providing the results of the non-professional hearing test to the user as a code that can be quickly identified by a professional, e.g., an audiologist. The invention also provides testing of the speech intelligibility issues in a hearing aid test, where such tests are administered around words, based upon the specific results of the hearing test.
[0026] The present invention also provides a means to show the user what having a hearing aid would do to improve quality of life by having the system play corrected words or sounds based upon the hearing loss detected. Experiencing such correction in an immediate fashion should improve the patient's motivation to fix the problem. The present invention provides step-by-step guidance on the next steps to be taken if hearing loss is found. Further, this invention also provides a means to store and organize the user test data to create a means for reuse of the data.
[0027] In a preferred embodiment, the present invention provides for a remotely accessible data storage media for use in testing hearing of an individual. The media comprises a plurality of hearing test queries, such as a frequency tone, word or sentence, and instruction data. The instruction data includes instructions for automatically or manually operating a local hearing test unit to perform a hearing test based on the hearing test queries retrieved from the media. The hearing test queries include at least one of a set of frequency versus amplitude hearing test and speech intelligibility queries, where the speech intelligibility queries are selectably accessible. The instruction data includes instructions (i) linked to at least one of the frequency versus amplitude queries and (ii) identifying selected user inputs associated with results of the frequency versus amplitude queries and corresponding to selected ones of the speech queries.
[0028] In a further embodiment, the media includes a memory for storing user information and user hearing test results obtained from performing the hearing aid testing with the test queries contained on the media, where the user information and the user hearing test results are generated at the hearing test unit.
[0029] In another embodiment, the media includes incentive data (e.g. electronic coupons) linked to selected ones of the instruction data. The instruction data, for example, indicate the end of a hearing test, or constitute a code corresponding to the hearing loss profile for the user obtained based on the results of a preliminary hearing test.
[0030] In a further embodiment, the media includes hearing test queries indexed with a hearing test code, where the code represents the results of a preliminary hearing test on the individual.
[0031] In a further embodiment, the media includes normal and modified word units having the same index as a hearing test code or one of the selected user inputs identified in the instruction data.
[0032] The present invention further provides a system for performing a hearing test including a central controller and a hearing test unit. The controller is coupled to the inventive data storage media, and the controller and media are located remotely from the hearing test unit. Each of the controller and the hearing test unit includes means for providing data communications over a data communications network. At least one of the controller and the media include a memory for storing user information and user hearing test results obtained from performing the hearing aid testing with the test queries of the media, where the user information and the user hearing test results are generated at the hearing test unit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Other objects and advantages of the present invention will be apparent from the following detailed description of the presently preferred embodiments, which description should be considered in conjunction with the accompanying drawings in which like references indicate similar elements and in which:
[0034] FIG. 1 is a high-level system diagram of an automated and convenient hearing testing system that collects and stores user information.
[0035] FIGS. 2 , 3 and 4 illustrate methods of using an automated and convenient pre-test hearing testing system that collects and stores user information.
[0036] FIG. 5 is a frequency vs. amplitude address lookup table.
[0037] FIGS. 6A and 6B illustrate a hearing test questionnaire.
DETAILED DESCRIPTION OF THE INVENTION
[0038] FIG. 1 is a high-level diagram of a preferred system 100 including a user 105 , a hearing test unit 120 , a network connection 130 , a central hearing health computer system 140 , and a telephone 121 .
[0039] User 105 represents the individuals (mass market) on whom a hearing test is to be administered. This is generally any and all individuals but, more specifically, the more than 10% of the population (e.g., 25 million Americans) that have hearing loss, including one out of four people older than 65.
[0040] Network connection 130 is a standard Internet connection or, alternatively, is a WAN, LAN, etc. Network connection 130 is the communication infrastructure between hearing test unit 120 and central hearing health computer system 140 . Network connection 130 allows central hearing health computer system 140 to remotely administer hearing aid tests, thereby giving central hearing health computer system 140 an opportunity to reach a large number of individuals.
[0041] Telephone 121 is a standard telephone capable of generating tone pulse from its keypad. Telephone 121 functions as an input/output device that allow user 105 to communicate with central hearing health computer system 140 .
[0042] Central hearing health computer system 140 further includes a computer 143 , a user data storage 145 , a modem 144 , and a series of hearing test programs 146 .
[0043] Central hearing health computer system 140 is a centrally located computer system that is connected to an Internet. Central hearing health computer system 140 is a central repository of all current audiological programs, audiological data, audiological research, sound “.wav” files, and speech and other sound simulations files. Central hearing health computer system 140 centralizes information so that all connected audiologists around the world can access current audiological test procedures, new standards, new algorithms for programming the DSP-based hearing aids, etc.
[0044] User data storage 145 is a memory region of central hearing health computer system 140 that stores data concerning user 105 including information such as demographics, age, name, date of birth, etc., and also includes user 105 's actual responses to the hearing tests.
[0045] Computer 143 is a computer that is capable of performing all conventional computer functions of reading and writing data to memory (within computer 143 ), reading and writing data to other connected computers, communicating through modem 144 or network connection 130 , and running hearing test programs 146 .
[0046] Hearing test programs 146 include the programs that execute the methods of the present invention.
[0047] Hearing test unit 120 further includes a test administrator computer 124 , a pair of headphones 122 , a keyboard 123 , a monitor 126 , a data storage 125 , and a series of hearing test programs 128 .
[0048] Hearing test programs 128 running on test administrator computer 124 perform the steps of uploading and running the current hearing test programs 146 on central hearing health computer system 140 to the memory (not shown) of test administrator computer 124 , and then downloading the obtained test results data to data storage 125 and central hearing health computer system 140 .
[0049] User 105 is an individual that tests his or her hearing to determine hearing loss. Test administrator computer 124 is essentially an automatic audiometer that is easily operable by user 105 , i.e., it does not need additional supervision. Automatic audiometers are well known in the prior art and any type can work with this invention. For example, U.S. Pat. No. 4,107,465, “Automatic audiometer system,” assigned to Centre de Recherche Industrielle du Quebec, describes an audiometer for testing the hearing characteristic of a person. The audiometer is entirely operable by the person, whereby technicians are not required. The audiometer comprises a source of audible and selectable fixed frequency signals. An automatic frequency selector switch selects a predetermined frequency signal from the source. A variable attenuator circuit is provided to automatically attenuate, in sequence, the predetermined frequency through a plurality of attenuation levels and according to a pre-selected mode of operation whereby to transmit a plurality of attenuated frequency signals. The person using the audiometer transmits the attenuated frequency signals for audible reception. Visual display lamps indicate the test frequencies and attenuation, permitting the person to fill out a test chart on corresponding sounds audible to his or her ears. A control circuit is provided to enable the frequency selector means and the variable attenuator in accordance with a pre-selected mode of operation.
[0050] Central hearing health computer system 140 uses computer 143 to communicate with hearing test unit 120 through network connection 130 . Central hearing health computer system 140 also operates user data storage 145 , which is a central database repository of information (which can later be reused) about user 105 . Depending on the specific application of this invention, data storage 125 and user data storage 145 can be mirror images of each other. User data storage 145 can also have user profile and hearing test information from prior tests, which can be updated to data storage 125 as required.
[0051] In a first method of operation of system 100 , user 105 can take a hearing test in one of two ways. First, user 105 could dial the toll-free telephone number given to him or her at a previous low-cost hearing test. The number dialed links user 105 to central hearing health computer system 140 through modem 144 . Computer 143 , recognizing the input from modem 144 , runs hearing test programs 146 and any data collected is stored in user data storage 145 . Hearing test programs 146 can be run in many ways, preferably where the hearing test program 146 sends sounds (tones) at various amplitudes and prompts user 105 to interact through either verbal or keypad responses. In addition, speech intelligibility can be tested by a program with pre-defined sentences that are output to user 105 for his or her understanding and response. In this way, user 105 can take low-cost, non-professional hearing tests at home. Even though it is understood that the telephone system has low bandwidth capability, some amount of useful testing can be done; digital telephone systems are also improving, adding higher frequency capability. It is further understood that, if user 105 had a code from a low-cost test that he or she had previously taken, the first request of the program would be for user 105 to enter the code using the telephone keypad.
[0052] A second, improved method of operation to take a hearing test is for user 105 to take the test on hearing test unit 120 . This device is a low-cost device that could be available for use at general practitioners' offices or other public areas, such as kiosks in shopping malls, eyeglass shops, or any other similar public area where it would make sense for user 105 to take a hearing test. In this method of operation, user 105 initializes hearing test unit 120 , which in turn uploads the current hearing test program 146 on central hearing health computer system 140 through network connection 130 . Hearing test unit 120 stores the program as the current hearing test program 128 . By using test administrator computer 124 , headphones 122 , keyboard 123 , and monitor 126 , user 105 interacts with system 100 in a similar manner as in first method of operation above. The program can be run in many ways, preferably where the hearing test program 128 sends sounds (tones) at various amplitudes and prompts user 105 to interact through either verbal or keypad responses. In addition, speech intelligibility can be tested by a program with pre-defined sentences that are output to user 105 for his or her understanding and response. In this way, user 105 can take low-cost, non-professional hearing tests in a variety of convenient settings. This is an improved system since hearing test unit 120 has higher bandwidth capability than the telephone system. It is further understood that, if user 105 had a code from a low-cost test that he or she had previously taken, the first request of the program would be for user 105 to enter the code using keyboard 123 .
[0053] There are several alternative ways of reusing user 105 test results and/or profile data that is stored in data storage 125 and user data storage 145 . For example, central hearing health computer system 140 can provide user 105 test data to better guide a physician to conduct a more detailed and thorough audiometric test on user 105 and to make recommendations on a remedy in case of hearing loss. User 105 test data from multiple users can also be used for due diligence and statistical analysis to determine preferences for certain users with specific profiles. This can allow for improved targeted marketing of hearing health products to the users.
[0054] System 100 is an automated and convenient pre-professional test hearing testing system that collects and stores user information.
[0055] FIG. 2 illustrates a method 200 of using system 100 , including the steps of:
[0056] Step 210 : Activating User Interface
[0057] In this step, user 105 activates test administration computer 124 , which can be found at general practitioners' offices or other public areas, such as kiosks in shopping malls, or any other similar public area where it would make sense for user 105 to take a hearing test.
[0058] Alternatively, user 105 can call into central hearing health computer system 140 from a remote location by using telephone 121 . However, current telephone technology limits the maximum test frequency, which can lead to a limited test level for user 105 . More so, telephones differ widely across levels of audibility, given that volume settings on telephones are highly variable. This further makes the use of current telephone technology limiting for this invention. As telephone technology improves, the use of telephone 121 to remotely conduct a hearing test can become more popular.
[0059] Step 220 : Conducting Hearing Test
[0060] In this step, user 105 takes a hearing test using either test administration computer 124 or central hearing health computer system 140 . One mode of operation is explained in the method described with reference to FIG. 3 .
[0061] Step 230 : Updating User Information Database
[0062] In this step, user data storage 145 is updated with user 105 's hearing test results either directly, if user 105 connected through telephone 121 , or indirectly when data storage 125 connects with user data storage 145 through network connection 130 and updates or adds the collected information from user 105 . Method 200 ends.
[0063] FIG. 3 illustrates a method 300 of conducting a hearing test using system 100 . It is assumed that user 105 has already connected either by using telephone 121 to connect to central hearing health computer system 140 directly or by using test administration computer 124 . Method 300 includes the steps of:
[0064] Step 310 : Collecting User Information
[0065] In this step, user 105 enters his or her personal profile and contact information by using either keyboard 123 or the keypad on telephone 121 , and the information is stored on data storage 125 . Note that before collecting information, user 105 is notified that his/her information will be strictly kept as private and secure from unwanted third parties. Other conventional voice response technology can also be used in place of the keypad for telephone 121 . If user 105 has received a code when taking a previous low-cost hearing test, the code is entered at this time. This code refers to a lookup table on computer 143 or test administration computer 124 to determine the results of the earlier test and is used to improve this hearing aid test.
[0066] Step 320 : Running Calibration
[0067] In this step, user 105 calibrates and initiates hearing test program 128 or hearing test program 146 , which provides a verbal set of directions that tells user 105 to listen to the following tone and to set the volume (e.g., via keyboard 123 ) to its lowest audible level. Setting the volume to its lowest audible level is an optimal environment to conduct an accurate hearing test. User 105 is then guided to the first frequency test module that is based upon the correct volume level set by the user.
[0068] Step 330 : Running Frequency Vs. Amplitude Tone Test
[0069] In this step, user 105 uses hearing test program 128 or hearing test program 146 to conduct a frequency vs. amplitude tone test. A frequency vs. amplitude tone test is detailed below in reference to FIG. 4 ; however, such tests are well known in the art and this invention only illustrates a simplified method.
[0070] Step 340 : Running Questionnaire
[0071] In this step, hearing test program 128 or hearing test program 146 conducts a questionnaire 600 (shown in FIGS. 6A and 6B ). By answering questionnaire 600 , user 105 can further confirm his or her level of hearing loss. The questions on questionnaire 600 can be easily modified according to the specific responses given by user 105 to hearing test program 128 or hearing test program 146 , and questions well known in the art can also be added.
[0072] Step 350 : Running Detailed Frequency Vs. Amplitude Tone Test
[0073] In this step, hearing test program 128 or hearing test program 146 conducts a detailed frequency vs. amplitude test of user 105 . This test is usually conducted to isolate and confirm user 105 's deficiency type. Detailed frequency vs. amplitude tone tests are well known in the art.
[0074] Step 360 : Running Frequency Vs. Amplitude Test in Conjunction with Questionnaire
[0075] In this step, hearing test program 128 or hearing test program 146 conducts a frequency vs. amplitude test on user 105 in conjunction with his or her responses from questionnaire 600 . For example, if user 105 has answered on questionnaire 600 that background noise affects him or her, a more detailed frequency vs. amplitude test can be run, with and without background noise, to determine the effects. Running detailed frequency vs. amplitude tone tests in conjunction with questionnaires is well known in the art.
[0076] Step 370 : Providing Incentives for Next Steps
[0077] In this step, if it has been determined that user 105 has a hearing loss, an added incentive to begin corrective measures can be provided to user 105 . For example, a $100 cost savings “coupon” on hearing aids can be provided as an incentive. Methods of printing and providing physical coupons, or providing electronic coupons via the Internet, are known in the art. Method 300 ends:
[0078] In addition in step 370 , following testing, the hearing test unit 120 executes a hearing test improvement demonstration program, which is stored in either the hearing test programs 126 or 146 , to provide that hearing aid corrected (modified) words and normal words are played for the individual. The modified words are amplified versions of the normal words which are used to demonstrate the improvement in the individual's hearing that would be achieved through use of a hearing aid, whereas the normal words do not include any amplifications.
[0079] FIG. 4 illustrates a method 400 of conducting a frequency vs. amplitude tone test, including the steps of:
[0080] Step 405 : Initializing X and Y Address Positions
[0081] In this step, hearing test program 128 or hearing test program 146 initiates the X and Y address positions of amplitude and frequency values to their starting positions. Values for the X and Y positions are shown in FIG. 5 , which illustrates a frequency vs. amplitude lookup table 500 that is used to administer the frequency vs. amplitude tone test on user 105 . Table 500 is divided into X addresses X 1 -X 5 that represent increments in amplitude, and Y addresses Y 1 -Y 5 that represent increments in frequency.
[0082] Step 410 : Loading Frequency/Amplitude Values from Address
[0083] In this step, the frequency and amplitude values corresponding to the X and Y address locations in table 500 are loaded into a frequency-amplitude player such as an amplifier.
[0084] Step 415 : Running Test
[0085] In this step, the frequency and amplitude values are played in headphones 122 . Alternatively, if user 105 is calling through telephone 121 , the frequency and amplitude values are played in through telephone 121 .
[0086] Step 420 : Getting Response
[0087] In this step, user 105 is asked a question such as whether the frequency and amplitude values are audible. User 105 responds to the question accordingly through keyboard 123 or telephone 121 .
[0088] Step 425 : Storing Response
[0089] In this step, user 105 's response to the question asked in step 420 is stored in data storage 125 or user data storage 145 . Central hearing health computer system 140 can later reuse this response.
[0090] Step 430 : Increasing X Address Position
[0091] In this step, the X address location in table 500 is increased.
[0092] Step 435 : Last X Address?
[0093] In this decision step, the program determines whether the last X address has been reached. If so, method 400 proceeds to step 440 ; if not, method 400 returns to step 410 .
[0094] Step 440 : Increasing Y Address Position and Initializing X Address
[0095] In this step, the Y address location in table 500 is increased and the X address location is initialized to its starting location.
[0096] Step 445 : Last Y Address?
[0097] In this decision step, the program determines whether the last Y address has been reached. If so, method 400 ends; if not, method 400 returns to step 410 .
[0098] FIGS. 6A and 6B illustrate questionnaire 600 that was referenced in method 300 .
[0099] Thus, the invention provides for the collection and storage of user information, via an automated and convenient pre-professional test hearing testing system, in a database that can be later accessed to allow for reuse of the information. Those of ordinary skill in the art will realize that the above description of a hearing testing system is illustrative only and not in any way limiting. Other embodiments of a hearing testing system will readily suggest themselves to such skilled persons.
[0100] Although preferred embodiments of the present invention have been described and illustrated, it will be apparent to those skilled in the art that various modifications may be made without departing from the principles of the invention. | System and method for conducting a hearing test that is accessible to a mass market of individuals with potential hearing loss. The hearing test is stored on a centrally located computer ( 140 ) that is accessible via communications device ( 121 ). The system provides step-by-step guidance on the next steps to be taken if hearing loss is found, and provides a means to store and organize the user test data to create a means for reuse of the data. | 0 |
FIELD OF THE INVENTION
[0001] This invention relates to vulcanizable diene rubber compounds which exhibit a high capacity for the addition of sulfur to be varied while processing safety is maintained, for the production of improved rubber moldings, particularly tire components.
BACKGROUND OF THE INVENTION
[0002] Due to the dynamic stresses on a tire, tire components require good thermal and mechanical stability in order to ensure good durability of the tire. With regard to mechanical stability, a high modulus and a high resistance to tear propagation, in particular, are desirable at a given hardness of the vulcanized material.
[0003] The economics of the use of tires, particularly truck tires, is to a major extent determined by the total number of possible remolds of the tire tread. Repeated remolding of the tire tread is only possible, however, to the extent which is permitted by the stressed carcass of the tire.
[0004] αω-bis(N,N′-diethylthiocarbamoyldithio)-alkanes and 1,2-bis(N,N′-dibenzylthiocarbamoyldithio)-ethane are known from Patent Applications EP 385 072, EP 385 073, EP 432 405 and EP 432 417 as crosslinking agents for diene rubber for the production of tire treads and tire sidewalls. A common feature of diethylamine derivatives is that they can release diethylamine during the vulcanization of the rubber compound. Diethylamine can form diethylnitrosamine, which is carcinogenic to humans. 1,2-bis-(N,N′-dibenzylthiocarbamoyldithio)-ethane is not, in fact, capable of forming dibenzylnitrosamine, which is carcinogenic to humans (see Druckrey et al., Z. Krebsforschung 69 (1967) 103), but based on the teaching of DE 22 56 511 the possibility cannot be ruled out for this compound, with its 1,2-dithioethanediyl radical, resulting in malodorous vulcanized materials (see page 17, paragraph 2), whereas α,ω-dithioalkanediyl radicals which comprise more than 4 carbon atoms result in vulcanized materials which result in no problems as with respect to odor.
[0005] In the aforementioned European Patent Applications, the crosslinking agents were used without sulfur additives. It is mentioned that the additional use of sulfur generally results in no advantages, since the reversion behavior of the vulcanized materials deteriorates.
[0006] EP 530 590 discloses a method of producing vulcanized diene rubber materials with a crosslinking agent system consisting of 1 to 4.5 parts by weight of 1,2-bis(N,N′-dibenzylthiocarbamoyldithio)-ethane or of 1,6-bis(N,N′-dibenzylthiocarbamoyldithio)-hexane, 0.05 to 0.3 parts by weight sulfur, and selected amounts of vulcanization accelerators. The particular teaching of the aforementioned patent is that the amount of crosslinking agent used can be reduced (economic aspects) by the use of very small amounts of sulfur, and that elastomers which exhibit a resistance to aging and reversion which was unattainable can be obtained with the avoidance of bloom phenomena and after relatively short times of vulcanization (page 7, lines 25 to 27). Vehicle tires and engine mountings are cited as examples of the use of vulcanized materials such as these.
[0007] Furthermore, DE 22 56 511 contains a very general discussion of the use of compounds of general formula A-S-S-R-S-S-A′ for the vulcanization of rubbers, wherein R constitutes almost any divalent organic radical, and A and A′ constitute a very large number of accelerator radicals, which also include N-substituted thiocarbamoyl radicals amongst others. The crosslinking agents can be used on their own or can also be used in combination with sulfur and vulcanization accelerators. The addition of elemental sulfur preferably falls within the range from 0.5 to 1.5 parts by weight sulfur with respect to 100 parts by weight rubber. Page 32, paragraph 2 contains the teaching that the crosslinking agents of the invention, in combination with amounts of sulfur greater than 1.5 parts by weight, result in a decrease in the level of processing safety of these rubber compounds.
[0008] One measure of the level of processing safety is the Mooney scorch time. A short Mooney scorch time signifies a low level of processing safety, whereas a long Mooney scorch time signifies a high level of processing safety. A high level of processing safety of rubber compounds is very desirable, because the addition of vulcanization retarders can thereby be dispensed with.
[0009] It is shown in DE 22 56 511, using master batch A (an NR compound), that the rubber compound according to Example 7 of Table VII, which comprises 1.0 parts by weight 1,2-bis-N,N′-dimethylthio-carbamoyldithio)-ethane and 1.7 parts by weight sulfur, has a Mooney scorch time (t 5 /121° C.) of only 25.7 minutes. Compared with this, the compound according to Example 1 of Table III (control example), which comprises 2.0 parts by weight sulfur and 0.5 parts by weight Santocure NS (benzothiazyl-2-tert.-butylsulphenamide, TBBS) as an accelerator, has a corresponding Mooney scorch time of 32.0 minutes, i.e. the level of processing safety of the rubber compound in Example 7 of Table VII, which comprises 1.7 parts by weight sulfur, has actually become inferior to that of the control example. As evidenced by Example 6 in Table VII, there is in fact a deterioration of the level of processing safety even at an addition of sulfur of more than 1.0 part by weight, as measured on the control compound (see Example 1, Table III). Rubber compounds which contain the crosslinking agents of the invention are suitable for the bonding or agglutination of natural or synthetic textile fibers (page 35, paragraph 2).
[0010] As described at the outset, there is, therefore, a pressing need for vulcanizable rubber compounds for the production of improved tire components, particularly with respect to industrial hygiene, processing safety of the rubber compound, and the mechanical and dynamic property profiles and aging behavior of vulcanized materials.
SUMMARY OF THE INVENTION
[0011] The object of the present invention is to provide vulcanizable rubber compounds, which exhibit a high capacity for the addition of sulfur to be varied while maintaining high processing safety, for the production of improved tire components. The rubber compounds according to the invention release no nitrosamines during vulcanization which are carcinogenic to humans. The vulcanized materials resulting from the rubber compounds are free from undesirable odors of organosulfur compounds, and not only do the vulcanized materials exhibit no deterioration, or exhibit only a slight deterioration in their technological properties during aging, but they are even improved before aging with respect to modulus and resistance to tear propagation, or their modulus remains virtually of the same standard while their resistance to tear propagation is improved without any deterioration in the standard of their other important technological properties, such as the loss factor tan δ at 70° C. or the heat build-up.
[0012] In this connection, it should be mentioned that the modulus and the resistance to tear propagation are usually diametrically opposed to each other, i.e. vulcanized materials with a high modulus usually exhibit a low resistance to tear propagation, and vice versa.
[0013] The object of the present invention has surprisingly been achieved by the vulcanization of a rubber compound based on diene rubbers which comprise a special crosslinking agent which provides C 6 -bridges, in combination with a selected amount of sulfur, and in the presence of vulcanization accelerators.
[0014] The present invention therefore relates to vulcanizable rubber compounds based on diene rubbers and customary additives, which are characterized in that the vulcanizing system contained in the compounds comprises
[0015] a) 0.5 to 3.8 parts by weight of compound (I)
R 2 N—(C═S)—S—S—(CH 2 ) x —S—S—(C═S)—NR 2 (I)
[0016] where R=(C 6 H 5 CH 2 );
[0017] and X=6,
[0018] b) 0.5 to 2 parts by weight sulfur and
[0019] c) 0.5 to 3.0 parts by weight of vulcanization accelerators, wherein the parts by weight are given in each case with respect to the use of 100 parts by weight of rubber.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The synthesis of chemical compound (I) of the crosslinking agent is described in principle in EP 0 432 405.
[0021] The rubber compound according to the present invention is produced in the manner known in the art by the customary mixing of the rubber components with known additives or supplementary materials, such as carbon black, plasticizers, antidegradants, zinc oxide, stearic acid or resins, as well as with the vulcanizing system, wherein the additives are used in customary amounts.
[0022] The following should be cited as diene rubbers in the present invention: natural rubber (NR), isoprene rubber (IR) and butadiene rubber (BR), as well as styrene-butadiene rubber (SBR) which can be produced either by the emulsion method or by the solution method. Equally good results are also obtained by using blends of these rubbers with each other.
[0023] With regard to diene rubber blends, a blend comprising 90 to 50 parts by weight, preferably 80 to 60 parts by weight, of NR, and 10 to 50 parts by weight, preferably 20 to 40 parts by weight, of BR, is particularly preferred.
[0024] The types of NR which are customarily used in the tire industry are suitable as NRs for the rubber compound according to the invention.
[0025] A BR which is particularly suitable for the rubber compound according to the invention is one which has a cis-1,4 content of 30 to 100 parts by weight, preferably of 90 to 100 parts by weight, per 100 parts by weight of rubber.
[0026] BR can be used in clear form or in oil-extended form. The use of clear BR is preferred.
[0027] Chemical compound (I) is used in amounts from 0.5 to 3.8 parts by weight, preferably in amounts from 0.5 to 3.5 parts by weight. The sulfur, which is customarily used in the rubber processing industry, or even insoluble sulfur, is suitable as the sulfur. The preferred amount of sulfur ranges from 0.5 to 2 parts by weight, more preferably from 0.5 to 1.5 parts by weight, with respect to 100 parts by weight of rubber used.
[0028] Known sulfur donors, for example, caprolactam disulphide, and admixtures thereof with sulfur, can also of course be used. The amount of sulfur donor, which is most favorable for the purpose of use, can easily be determined by preliminary tests.
[0029] Very different types of vulcanization accelerators can be used, and are subject to no restriction. Mercaptobenzthiazole (MBT), dibenzothiazyl disulphide (MBTS), sulphenamides based on MBT, such as benzothiazyl-2-cyclohexylsulphenamide (CBS), benzothiazyl-2-dicyclohexyl-sulphenamide (DCBS), benzothiazyl-2-tert.-butylsulphenamide (TBBS) and benzothiazyl-2-sulphenomorpholide (MBS) are preferably used. The vulcanization accelerators are used in amounts of 0.5 to 3.0 parts by weight, preferably 0.5 to 2.5 parts by weight, with respect to 100 parts by weight of rubber used.
[0030] A mixture of CBS and MBS is preferably used. Mixtures of other vulcanization accelerators can also be used, however, the optimum composition with respect to the type and amount thereof can easily be determined by experiment.
[0031] Vulcanization of the rubber compound according to the present invention is effected in the known manner at temperatures from about 120° to 220° C., preferably from 140° to 200° C.
[0032] The rubber compounds according to the present invention can be used for the production of rubber moldings, particularly tire components, and are most preferably used for the production of improved apeces, sidewall strips and chafer strips, shoulder cushions, belt strips, sidewall inserts and tread slape bases, as well as for the treads of tires, particularly truck tires.
[0033] The invention is further illustrated but is not intended to be limited by the following examples in which all parts and percentages are by weight unless otherwise specified.
EXAMPLES
[0034] Details of the Experimental Methods Used
[0035] The following test methods or test devices were used: Mooney viscosity: DIN 53 523, large rotor, 100° C., pre-heat time 1 minute, test duration 4 minutes. Mooney scorch: DIN 53 523, large rotor, 130° C., pre-heat time 1 minute. Rheometer: ASTM D 2084, Monsanto MDR 2000 E, 170° C. Tensile testing: DIN 53 405, dumb-bell. Hardness: DIN 53 505. Rebound resilience: DIN 53 512. Dynamic properties: DIN 53 533, Goodrich Flexometer, 100° C./25 minutes, pre-strain 1 MPa, stroke 4.45 mm. Viscoelastic properties: DIN 53 513/ISO 4664, Roelig Test, 10 Hz.
Examples 1-4
[0036] The test compounds listed in Table 1 were produced using an internal mixer Type GK 1,5 E manufactured by Werner & Pfleiderer, at a rotor speed of 40 rpm and at a chamber and blade temperature of 50° C. (ram pressure 8 bar, degree of filling 65%). The quantities are given in parts by weight per 100 parts by weight rubber.
TABLE 1 Test formulations Compound Example 1 Example Example Example 4 Number (Comparison 1) 2 3 (Comparison 2) NR a) 80 80 80 80 BR b) 20 20 20 20 Carbon black 40 40 40 40 N234 Silica c) 8 8 8 8 Zinc oxide d) 10 10 10 10 Plasticizer e) 3 3 3 3 Tackifier f) 2 2 2 2 6PPD g) 1.8 1.8 1.8 1.8 TMQ h) 1.2 1.2 1.2 1.2 Stearic acid 0.75 0.75 0.75 0.75 Resorcinol formulation (66.6%) i) 1.2 1.2 1.2 1.2 HMT j) 0.6 0.6 0.6 0.6 CBS k) 0.7 0.7 0.7 0.7 MBTS l) 0.3 0.3 0.3 0.3 Sulfur 3 1 0.5 0.5 Cross-linking 0 2 3 4 agent (I)
[0037] The mixing sequence for the preparation of the compounds was selected as follows:
t = 0 sec addition of polymers t = 10 sec ram down t = 30 sec ram up, addition of carbon black and plasticizer, ram down t = 90 sec ram up, addition of silica, zinc oxide, tackifier, antidegradants, stearic acid and resorcinol, ram down t = 210 sec sweep t = 240 sec dump.
[0038] On emptying the kneader, the temperatures of the mixed materials were within the range from 91 to 92° C.
[0039] HMT, as well as the vulcanization system consisting of sulfur, CBS, MBTS and crosslinking agent (I) were mixed in on a roll at a mixing temperature of about 60° C.
[0040] The rheological data which were determined on the finished rubber compounds are given in Table 2.
TABLE 2 Rheological data on test compounds Compound Example 1 Example Example Example 4 Number (Comparison 1) 2 3 (Comparison 2) ML (1 + 4) 64 69 67 73 100° C. (MU) Scorch time 15.3 23.3 28.0 29 (120°)t 5 (min) Rheometer 150° C. ts01 (min) 2.1 3.5 4.5 4.5 t95 (min) 10.1 9.0 12.9 13.4 Smin (dNm) 1.6 2.6 2.6 2.5 S′max (dNm) 17.9 19.5 18.6 19.8 Send, 30 min 17.6 19.3 18.5 19.7 (dNm) Rheometer 150° C. ts01 (min) 0.5 0.7 0.9 0.9 t95 (min) 1.7 1.7 2.4 2.5 Smin (dNm) 1.4 2.4 2.3 2.3 S′max (dNm) 17.7 18.1 17.1 18.4 Send 30 min 11.1 17.0 16.7 18.2 (dNm)
[0041] The rubber compounds according to the present invention were vulcanized at 150° C. (vulcanization time: t95+mold-related warming-up time). The test results on the vulcanized materials are given in Table 3.
TABLE 3 Properties of vulcanized test products Vulcanized Example 1 Example Example Example 4 product number (Comparison 1) 2 3 (Comparison 2) Tensile 21 24 22 20 strength (MPa) Elongation at 440 452 423 382 break (%) Modulus 100 2.4 2.8 2.7 2.9 (MPa) Modulus 300 12.4 14.2 13.9 14.7 (MPa) Resistance to 28 41 45 25 tear propagation (N/mm) Hardness, 65 66 64 66 23° C. (Shore A) Hardness, 63 64 62 64 70° C. (Shore A) Rebound 60 62 59 63 resilience, 23° C. (%) Rebound 69 73 72 73 resilience, 70° C. (%) Goodrich flexometer: temperature 11 8 8 9 increase (° C.) Flow (%) 5.3 0.9 0.6 1.0 Permanent 7.1 1.6 1.6 1.2 set (%) Roelig test: Tan δ, 0° C. 0.113 0.104 0.104 0.108 Dyn. modulus 6.38 6.76 6.63 7.09 E′, 0° C. (MPa) Loss modulus 0.723 0.700 0.689 0.767 E″, 0° C. (MPa) Tan δ, 70° C. 0.043 0.035 0.041 0.050 Dyn. modulus 5.91 6.23 5.95 6.28 E′, 70° C. (MPa) Loss modulus 0.254 0.243 0.242 0.311 E″, 70° C. (MPa)
[0042] The examples teach that the rubber compounds according to the present invention exhibit a high level of processing safety, and result in vulcanized materials with an improved modulus and with an improved resistance to tear propagation at the same time, and in addition, exhibit low heat build-up and a low tan δ at 70° C.
Example 5
[0043] The procedure was the same as that used in Example 2 of Table 1, except that 2.0 parts by weight of sulfur were used instead of 1.0 parts by weight of sulfur and 1.0 part by weight of crosslinking agent (I) was used instead of 2.0 parts by weight of crosslinking agent (I).
[0044] The Mooney viscosity ML (1+4) 100° C. of the compound obtained was 66 and the Mooney scorch time t 5 was determined as 21 minutes at 120° C.
[0045] After the corresponding vulcanization of the compound, the modulus 100 was 3.2 MPa; the resistance to tear propagation was 37 N/mm; and the temperature increase in the Goodrich Flexometer was determined to be 8° C. The Roelig test gave a tan δ of 0.035 at 70° C.
[0046] This example teaches that, compared with the control compound (see Example 1), rubber compounds according to the present invention even exhibit excellent processing safety when the addition of sulfur amounts to 2.0 parts by weight per 100 parts by weight of rubber.
Examples 6 and 7
[0047] The test compounds listed in Table 4 were produced using the internal mixer described in Examples 1-4 at a rotor speed of 40 rpm and at a chamber and blade temperature of 50° C. (ram pressure 8 bar, degree of filling 65%). The quantities are given in parts by weight per 100 parts by weight rubber.
TABLE 4 Test formulation Example 6 Example 7 Compound number 1 (Comparison) 2 NR a) 100 100 Carbon black N375 50 50 Zinc oxide d) 5 5 Plasticizer e) 3 3 6PPD g) 2 2 TMQ h) 1 1 Stearic acid 1 1 Microcrystalline wax m) 1 1 CBS k) 1 1 Sulfur 1.5 0.8 Crosslinking agent (I) 0 1.5
[0048] The mixing sequence for the preparation of the compounds was selected as follows:
t = 0 sec addition of polymers t = 10 sec ram down t = 60 sec ram up, addition of carbon black, plasticizer, zinc oxide, stearic acid, ram down t = 120 sec ram up, addition of antidegradants and wax, ram down t = 180 sec sweep t = 240 sec dump
[0049] On emptying the kneader the temperatures of the mixed materials were within the range from 112° to 114° C.
[0050] The vulcanization system consisting of sulfur, accelerator and crosslinking agent (I) was mixed in on a roll at a mixing temperature of about 65° C.
[0051] The rheological data which were determined on the finished mixed rubber compounds are given in Table 5.
TABLE 5 Rheological data of the test compounds Example 6 Example 7 Compound number 1 (Comparison) 2 ML (1 + 4) 100° C. (MU) 75 73 Scorch time (120° C.) t 5 (min) 21 26 Rheometer, 160° C. ts01 (min) 1.6 2.1 t90 (min) 3.6 4.0 t95 (min) 4.0 4.9 Smin (dNm) 3.4 3.2 S′max (dNm) 16.8 17.8 Send, 30 min (dNm) 13.7 18.0 Reversion (%) 18 0 Rheometer, 180° C. ts01 (min) 0.5 0.8 t90 (min) 1.1 1.5 t95 (min) 1.2 1.9 Smin (dNm) 3.3 2.9 S′max (dNm) 16.4 16.6 Send, 30 min (dNm) 10.8 15.7 Reversion (%) 34 5
[0052] The reversion was calculated as follows: (S′max−Send)/S′max×100%
[0053] The rubber compounds were vulcanized at 160° C. (vulcanization time: t95+mold-related warming-up time). The test results for the vulcanized materials are given in Table 6.
TABLE 6 Properties of vulcanzized test products Example 6 Example 7 Vulcanized product number 1 (Comparison) 2 Tensile strength (MPa) 27 28 Elongation at break (%) 550 529 Modulus 100 (MPa) 2.1 2.8 Modul 300 (MPa) 11.5 13.4 Hardness, 23° C. (Shore A) 67 68 Hardness, 70° C. (Shore A) 61 62 Rebound resilience, 23° C. (%) 43 40 Rebound resilience, 70° C. (%) 56 52 Resistance to tear propagation (N/mm) 38 92 Abrasion (Emery 40) (mm 3 ) 161 112 Goodrich flexometer: Temperature increase (° C.) 27 21 Flow (%) 8.7 2.3 Roelig test: tan δ, 0° C. 0.215 0.222 Dyn. modulus E′, 0° C. (MPa) 8.649 9.847 Loss modulus E″, 0° C. (MPa) 1.859 2.188 tan δ, 70° C. 0.110 0.111 Dyn. modulus E′, 70° C. (MPa) 5.229 5.896 Loss modulus E″, 70° C. (MPa) 0.577 0.656
[0054] The example teaches that the rubber compound according to the invention exhibits improved processing safety and results in a vulcanized material with improved abrasion resistance (the lower the abrasion, the higher the abrasion resistance) and an improved modulus together with improved resistance to tear propagation. In addition the vulcanized material according to the invention exhibits lower heat build-up.
[0055] 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. | This invention relates to vulcanizable diene rubber compounds with a high capacity for the addition of sulfur to be varied while processing safety is maintained, for the production of improved rubber moldings, particularly tire components. | 2 |
RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application Serial No. 60/184,379, filed Feb. 23, 2000, the disclosure of which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
The present invention relates to methods of screening subjects for mitochondrial dysfunction.
BACKGROUND OF THE INVENTION
A wide variety of clinical manifestations are due to mutations in mitochondrial DNA, but are difficult to diagnose due to the varied clinical picture and the lack of sensitive or specific diagnostic testing. Past efforts to document mtDNA mutations in children believed to have mitochondrial disorders have been hampered by the size of the mitochondrial genome and the presence of numerous benign polymorphisms.
Mitochondria are eukaryotic cytoplasmic organelles where oxidative phosphorylation takes place, and are often termed the ‘power plant’ of the cell. In animal cells, the mitochondria is the only cytoplasmic organelle that contains DNA. Human mitochondrial DNA (mtDNA) is a circular molecule of about 16,600 nucleotide pairs which encode thirteen of the at least 82 protein subunits of the complexes in the oxidative phosphorylation pathway, both ribosomal RNAs, and all of the 22 transfer RNAs required for mitochondrial protein synthesis. However, the majority of proteins located in the mitochondria are encoded by nuclear DNA (chromosomal DNA) and translated by cytoplasmic ribosomes, and then imported to the mitochondria. Therefore, a “mitochondrial disorder” can be secondary to a mutation in either the nuclear DNA or in the mitochondrial DNA.
The entire human mitochondrial DNA (mtDNA) sequence has been determined (see MITOMAP: Human Mitochondrial Genome Database, Center for Molecular Medicine, Emory University, Atlanta, Ga., USA (1998); Wallace et al. (1995) Report of the committee on human mitochondrial DNA, In: Cuticchia A J (Ed) Human gene mapping 1995: A Compendium, Johns Hopkins University Press, Baltimore, pp 910-954 (1995)).
Mitochondrial genetics differ from nuclear (standard or Mendelian) genetics. Virtually all the mtDNA of a zygote is derived from the oocyte, and mtDNA disorders are transmitted by maternal inheritance. Maternal-linked (matrilineal) relatives presumably have identical mtDNA sequences, except perhaps at the site of a new mutation. Additionally, the mtDNA mutation rate is substantially higher than that of the nuclear DNA. Most cells contain hundreds to thousands of mitochondria, and each mitochondria contains several copies of mtDNA, resulting in high mtDNA copy number. In normal individuals, essentially all of the mtDNA molecules are identical (homoplasmy). However, if there is a mutation in mtDNA, the mutant mtDNA and the normal (wild type) mtDNA often coexist in the same cell or tissue (heteroplasmy).
Because of the high mutation rate, mtDNA has numerous polymorphisms. Almost always these polymorphisms are homoplasmic. In contrast, most recognized pathogenic mtDNA mutations are heteroplasmic, especially when disease manifests during childhood (Shoffner and Wallace (1995) In: The Metabolic and Molecular Basis of Inherited Disease (7 th Ed.), New York, McGraw Hill, 1535-1629).
As a result of segregation in the pre-oocyte stage, each ova of an affected woman has a different proportion of mutant versus normal mtDNA, which can range from virtually 0 to 100%. Each of her children, therefore, will inherit differing amounts of mutant mtDNA. In addition, normal and mutant mtDNA randomly segregate during the cell divisions of embryogenesis, resulting in different proportions of mutant mtDNA residing in different tissues. The presence of clinical disease in a given tissue is dependent on the specific mutation, the percent of mutant mtDNA and the threshold for that tissue. The percentage of mutant mtDNA necessary to cause clinical symptoms varies from tissue to tissue; for example, 80% mutant mtDNA may be clinically silent in liver but cause symptoms in tissues with higher energy requirements, such as muscle or brain (Shoffner et al. (1991) Adv. Hum. Genet. 19:267). Since the mutant mtDNA load varies between matrilineal family members, as well as between tissues within each individual, the clinical manifestations of a mtDNA mutation vary widely among affected family members. Healthy family members with mutant mtDNA levels below threshold are common. These individuals, if female, are ‘carriers’ as their children will inherit their mitochondria and, if inherited mutant mtDNA levels are above threshold, the children will be affected. A well known example is the A3243G mtDNA mutation, in which family subjects exhibit variable manifestations, ranging from stroke (usually associated with relatively higher degrees of mutant heteroplasmy) to those (with lesser mutant loads) with diabetes, deafness, or asymptomatic carriers. This phenomenon of varied clinical presentation has been observed with other mtDNA mutations as well.
As the mtDNA mutation rate is high, mtDNA disorders may be due to new mtDNA mutations; in such cases matrilineal relatives will be unaffected. In other cases, mothers harbor small degrees of mutant heteroplasmy and are clinically normal or only mildly affected. In a minority of cases, multiple matrilineal relatives harbor various amounts of mutant mtDNA in their tissues and exhibit varying clinical manifestations.
A broad spectrum of disease manifestations has been associated with systemic mtDNA mutations. These mutations can be either single point mutations, or large rearrangements (deletions and/or duplications). Rearrangements usually are spontaneous, although they may be maternally inherited or mendelianly inherited secondary to predisposing nuclear mutations.
Clinical mitochondrial dysfunction may be defined as idiopathic neuromuscular and/or multisystem disease, biochemical signs of energy depletion, and lack of another diagnosis. Mitochondrial disorders are evidenced when the cellular supply of energy is unable to keep up with demand; symptoms predominate in tissues with the highest energy requirements (brain and muscle). Mitochondrial disorders are most commonly displayed as neuromuscular disorders, including developmental delay, seizure disorders, hypotonia, skeletal muscle weakness and cardiomyopathy. Other manifestations which have been reported include gastroesophageal reflux, apnea, optic atrophy, deafness, acute liver failure, diabetes mellitus, and other hormonal deficiencies.
Mitochondrial disorders are often not suspected until late in a diagnostic work-up. Confirmation of a mitochondrial disorder is, at present, a time-consuming and expensive process, and may include lactic acid measurement in body fluids and diagnostic muscle biopsy for electron microscopy and assay of the electron transport chain activities in vitro. However, these methods rarely specify the mode of inheritance or allow for presymptomatic or prenatal diagnosis.
SUMMARY OF THE INVENTION
A method of screening a subject for mitochondrial dysfunction is disclosed. The method comprises detecting the presence or absence of single nucleotide changes in a hypervariable region of the mitochondrial DNA of said subject, the presence of such changes indicating that said subject is afflicted with or at risk of developing mitochondrial dysfunction.
Also disclosed is the use of a means for detecting the presence or absence of single nucleotide changes in a hypervariable region of the mitochondrial DNA of a subject in or for determining if that subject is afflicted with or at risk of developing mitochondrial dysfunction.
The foregoing and other objects and aspects of the present invention are explained in greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the pedigrees in patients 1 and 8. Each of the disease manifestations present in these families is consistent with a possible mitochondrial disorder. Squares=males; circles=females; and circles within squares=either gender. Arabic numbers within symbols indicate the number of (normal) individuals. The arrows point to our cases (probands).
FIG. 2 shows an expanded diagram of human mtDNA-CR. The mtDNA-CR is defined as the area flanked by the tRNA genes for proline (tRNA Pro ) and phenylalanine (tRNA Phe ) (boxes with diagonal stripes). The location of each heteroplasmic nucleotide found among the cases described herein are marked by black lines and by the nucleotide number. Although not precisely defined, the approximate locations are noted for the hypervariable regions (HV1 and HV2, box with vertical stripes), evolutionary conserved sequence blocks (CSBs, solid boxes), displacement loop (D-loop, open box), the origin of heavy strand replication (O H ), and the transcription initiation sites for the 2 heavy strand (H1 and H2) and light strand (L) transcripts (arrows indicating the direction of transcription). The cross-hatched boxes at the bottom of the figure depict the areas screened by each of the PCR-amplified segments described herein.
FIG. 3 shows a computer scanned image of a TTGE gel of the 7S segment in 5 unrelated individuals: a normal control (lane 1), a child with length heteroplasmy at 16184 (lane 2), two subjects with different point heteroplasmic variants (lanes 3 & 4), and rho negative cell culture (lane 5). As shown here, in the absence of heteroplasmy (homoplasmy) a single distinct band is seen on the gel, while heteroplasmic samples usually demonstrate 3 or 4 bands on TTGE, corresponding to the predicted 2 homoduplex and 2 heteroduplex species (often the homoduplex bands are not separated).
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention is primarily intended to be carried out on human subjects, including both male and female subjects, of any age, including juvenile subjects. The method may be carried out on subjects who have been previously diagnosed as afflicted with mitochondrial dysfunction, or as a prognostic test on subjects who have not yet been diagnosed as afflicted with mitochondrial dysfunction. The test may be carried out as a screening procedure, wherein a positive result in the test indicates increased risk of mitochondrial dysfunction.
The mtDNA hypervariable region from which changes or mutations indicative of mitochondrial dysfunction generally consists of hypervariable region HV1 and HV2. Any change or mutation set forth in EXAMPLES hereto may be used in carrying out the test.
The changes or mutations described herein may be detected by any suitable technique, including but not limited to DNA amplification techniques such as described in U.S. Pat. No. 5,767,248 to Roses et al., the disclosure of which is incorporated herein by reference, adapted to be carried out on the changes or mutations described herein.
EXAMPLE 1
Inheritance of Mitochondrial Disorders
Children with idiopathic neuromuscular and/or multi-system disease manifestations are frequently encountered in pediatric tertiary practice. Some of these children bear one or more descriptive diagnoses such as mental retardation, epilepsy, migraine or cardiomyopathy. Increasingly, a proportion of these children are found to have biochemical signs of a possible defect in energy metabolism such as an elevated body fluid lactate, abnormal urine organic acids and/or mitochondrial proliferation by enzyme analysis in muscle. Whether these findings represent primary inborn errors of mitochondrial energy metabolism (‘mitochondrial disorders’) or non-specific secondary phenomenon remains controversial.
It has been observed that many of these children have matrilineal relatives with widely different, often transient and mild, neuromuscular and/or multi-system manifestations, including migraine (FIG. 1 ). This observation suggests that a maternally-transmitted factor may be involved in the development of disease manifestations in a substantial proportion of cases. Since mitochondria contain their own DNA (mtDNA) which is maternally transmitted (Shoffner and Wallace (1995) Oxidative phosphorylation diseases. In: Scriver C R, Beaudet A L, Sly W S, Valle D, editors. The metabolic and molecular bases of inherited disease , 7th ed. New York: McGraw-Hill, pg 1535-629; Chinnery and Turnbull (1997) Q J Med, 190:657-66), mtDNA sequence variations likely constitute this maternally-transmitted factor. However, known mtDNA mutations are infrequently (<5%) identified in children suspected of having a mitochondrial disorder (Liang and Wong (1998) Am J Med Genet , 77:395-400), suggesting that additional pathological mtDNA variants remain to be discovered.
Mitochondrial genetics differs in many aspects from Mendelian, or nuclear, genetics. Mitochondrial DNA is a 16,569 base pair circular molecule which encodes 13 protein subunits of the mitochondrial respiratory chain, as well as the 22 transfer RNA and 2 ribosomal RNA genes required for the translation of the mtDNA-encoded proteins (Shoffner and Wallace (1995) Oxidative phosphorylation diseases. In: Scriver C R, Beaudet A L, Sly W S, Valle D, editors. The metabolic and molecular bases of inherited disease, 7th ed. New York: McGraw-Hill, pg 1535-629). Mitachondrial DNA exists at high copy number, usually on the order of hundreds or thousands of genomes per cell. Heteroplasmy, defined as the existence of two or more different mtDNA sequences in the same cell, is associated with several, predominantly neuromuscular and/or multi-system disease states in man (Shoffner and Wallace (1995) Oxidative phosphorylation diseases. In: Scriver C R, Beaudet A L, Sly W S, Valle D, editors. The metabolic and molecular bases of inherited disease, 7th ed. New York: McGraw-Hill, pg 1535-629; Chinnery and Turnbull (1997) Q J Med, 190:657-66). Over 80 different pathological mtDNA point mutations have been described to date, and the vast majority exist in patients in a heteroplasmic state along with wild-type genomes (Shoffner and Wallace (1995) Oxidative phosphorylation diseases. In: Scriver C R, Beaudet A L, Sly W S, Valle D, editors. The metabolic and molecular bases of inherited disease, 7th ed. New York: McGraw-Hill, pg 1535-629; Kogelnik et al. (1996) Nuc Aci Res, 24:177-9. In contrast, normally occurring mtDNA point sequence variants (polymorphisms) are almost always homoplasmic (only one mtDNA sequence present) (supra). Clinical symptoms occur once the proportion of mutant mtDNA molecules exceeds a threshold which is both tissue and mutation specific (Shoffner and Wallace (1995) Oxidative phosphorylation diseases. In: Scriver C R, Beaudet A L, Sly W S, Valle D, editors. The metabolic and molecular bases of inherited disease, 7th ed. New York: McGraw-Hill, pg 1535-629; Chinnery and Turnbull (1997) Q J Med, 190:657-66). Partially in response to varying proportions of mutant and wild-type heteroplasmy among different tissues within each individual and among different family members, maternal inheritance is often characterized by widely variable clinical manifestations, age of onset and severity among members of the same family (supra).
As the only large non-coding region in the mitochondrial genome, the approximate 1 kilobase (kb) mtDNA control region (CR) is involved in mtDNA replication, transcription and membrane attachment (FIG. 2) (Shoffner and Wallace (1995) Oxidative phosphorylation diseases. In: Scriver C R, Beaudet A L, Sly W S, Valle D, editors. The metabolic and molecular bases of inherited disease, 7th ed. New York: McGraw-Hill, pg 1535-629; Kogelnik et al. (1996) Nuc Aci Res, 24:177-9. Control region mutations which interfere with these and other ‘regulatory’ functions constitute a plausible mechanism for human disease, although disease-causing mutations in this region have not been reported. Within the mtDNA-CR are 2 highly polymorphic regions, termed hypervariable region 1 and 2 (HV1, HV2) (supra). A very common HV1 variant consisting of an expanded homopolymeric tract of cytosines (length heteroplasmy) was recently reported as associated with insulin resistance (Poulton et al. (1998) Diabetologia, 41:54-8). The present study shows the presence of multiple heteroplasmic and homoplasmic single nucleotide changes in the hypervariable regions of the mtDNA-CR in 13 of 67 children with idiopathic neuromuscular and/or multi-system disease manifestations and an elevated body fluid lactate concentration.
EXAMPLE 2
Case Reports
Clinical and laboratory findings in each of the 11 children with mtDNA-CR point heteroplasmy patterns on temporal temperature gradient gel electrophoresis (TTGE) are listed in Table 1. Although there is substantial variability in clinical manifestations among the 11 children as a whole, many cases cluster into clinically-based groups, some of which may be syndromic. The following 6 cases were chosen for a more detailed description in order to demonstrate the range of phenotypic expression. Patient 8 was previously reported in brief (Boles and Williams (1999)- Dig Dis Sci, 44 (Suppl.):103S-107S. Pedigrees for patients 1 and 8 are shown in FIG. 1 .
TABLE 1
Patient #1
Patient #2
Patient #3
Brief Clinical
Reversible severe
Reversible severe
Reversible severe
Description
cardiomyopathy
cardiomyopathy
cardiomyopathy
Age/Sex/Race
7/M/B
4/F/H
2/F/H
Heteroplasmy
16168C-T
Insufficient DNA
16093T-C
Growth
Failure-to-thrive,
Early
Short stature
Short stature
failure-to-thrive
Developmental
None
None
Mild
Delay
Seizures
None
None
None
Skeletal Muscle
Hypotonia,
Mild atrophy
Weakness, Fatigue
Weakness, Atrophy
Cardiac Muscle
Dilated
Dilated
Dilated
cardiomyopathy
cardiomyopathy
cardiomyopathy
Gastrointestinal
Chronic diarrhea
Normal
Normal
Other Clinical
Pancytopenia
None
Hydrops,
Congestive failure
Clinical Course
Improved
Improved
Improved
Highest Lactate
4.8 mM
2.0 mM
2.5 mM
Urine Organic
Ketones
Normal once
Krebs cycle,
Acids
Generalized organic
aciduria
Cranial Imaging
Not done
Not done
CT:
Mild atrophy
Muscle Biopsy
Increased variation in
Not done
High citrate
muscle fiber sizes,
synthase
Increased lipid,
High citrate synthase,
Low complex 1, 3, 4
Family History
Maternal history of
Sporadic
Sporadic
migraine
Patient #4
Patient #5
Patient #8
Brief Clinical
Fasting
Fasting
Migraine/
Description
hypoglycemia
hypoglycemia
dysautonomia
Age/Sex/Race
3/M/C
4/F/C
12/F/C
Heteroplasmy
16481C-T
Insufficient DNA
16176C-T
16338A-G
Growth
Normal
Normal
Normal
Developmental
None
None
None/gifted
Delay
Seizures
Tonic and absence
None
None
Skeletal Muscle
Episodes of weakness
Normal
Normal
and muscle cramps,
Hypotonia in infancy
Cardiac Muscle
Normal
Normal
SVT
Gastrointestinal
Normal
GER, constipation,
Cyclic vomiting
multiple episodes
of acute
abdominal pain
Other Clinical
3 episodes of
Monitored for
Dilated left ureter,
hypoglycemia
possible sleep
Leg cramps with
and/or altered
apnea,
exercise
mental status
Hypoketotic
with fasting,
hypoglycemia
Chronic fatigue,
with fasting,
asthma
ADHD
Clinical Course
Improved
Improved, except
Improved
for ADHD
Highest Lactate
3.5 mM
Normal once
7.4 mM
Urine Organic
Krebs cycle
Lactate, Ketones,
Lactate, Ketones,
Acids
Free fatty acids,
Krebs cycle
Glutarate
Cranial Imaging
MRI: Increased T2
Not done
Not done
signal in basal
ganglia
Muscle Biopsy
Not done
Not done
Increased variation
in muscle fiber
sizes,
Increased lipid,
High citrate
synthase,
Low complex 1
Family History
Mildly affected
Unknown
Maternal
brother
(adopted)
Patient #9
Patient #10
Patient #11
Brief Clinical
Mental retardation/
Neonatal severe
Mental retardation/
Description
spasticity
multi-system
spasticity
disease
Age/Sex/Race
5/F/H
0/F/C
5/M/H
Heteroplasmy
16259C-T
16186C-T
HV2
16278C-T (mom)
16288T-C
Growth
Mild short stature
Failure-to-thrive
Short stature,
Microcephaly
Developmental
Profound
Vegetative
Profound
Delay
Seizures
Probable as infant
Myoclonic
Brief clonic
Skeletal Muscle
Spastic
Hypertonia
Spastic
quadriplegia
quadriplegia
Cardiac Muscle
Normal
Hypertrophic
Normal
cardiomyopathy,
Cardiac arrests
Gastrointestinal
Normal
Esophageal atresia,
Severe GER,
Severe dysmotility
Upper GI bleeding
Other Clinical
Optic atrophy,
Acute renal
Optic atrophy,
Strabismus,
failure,
Cortical blindness
Nystagmus
Multiple
Obstructive sleep
infections,
apnea
Left superior vena
cava and aortic
arch
Clinical Course
Static
Improved, then
Static
died
Highest Lactate
3.5 mM
19 mM
3.6 mM
Urine Organic
Normal once
Lactate, Ketones,
Mild ketones once
Acids
Ethylmalonate,
Krebs cycle,
Generalized
organic
aciduria
Cranial Imaging
MRI:
CT:
MRI:
Leukodystrophy
Thalamic infarcts
Ulegyria
Muscle Biopsy
Not done
Increased variation
Focal increased
in muscle fiber
mitochondrial
sizes,
staining
Low complex 1, 4,
[High citrate
synthase in
sibling]
Family History
Sporadic
Identically
Identically affected
affected male and
male and female
female siblings
siblings who died,
who died,
First cousin parents
HV1 heteroplasmy
in father
Patient #12
Patient #13
Brief Clinical
Reversible multi-system
Reversible multi-system
Description
disease
disease
Age/Sex/Race
3/F/H
5/F/H
Heteroplasmy
16215A-T
16285C-T
Growth
Failure-to-thrive,
Failure-to-thrive,
Short stature
Short stature
Developmental
Mild
Mild-moderate
Delay
Seizures
Complex partial
In infancy only
Skeletal Muscle
Hypotonia
Normal
Cardiac Muscle
Normal
Normal
Gastrointestinal
Pyloric stenosis,
Gastrostomy
GER, DGE
Other Clinical
Cleft palate
Bronchopulmonary
dysplasia,
Ventilator dependent
Clinical Course
Improved
Improved
Highest Lactate
3.4 mM
5.4 mM
Urine Organic
Lactate, Ketones,
Ketones,
Acids
Krebs cycle
Free fatty acids,
Generalized organic
aciduria
Cranial Imaging
MRI: Normal
Not done
Muscle Biopsy
Increased variation in
Not done
muscle fiber sizes,
Increased lipid,
High citrate synthase
Family History
Maternal
Maternal
H = Hispanic (of any race), B = Black/African American, C = Caucasian. Mixed racial children are listed as per their matrilineal race. The racial distribution in our cases resembles that of our referred patient population. The number of substitutions includes only single base pair changes, either homoplasmic or heteroplasmic, and scored as the number found in the patient/the number found in the paired haplogroup-matched control.
SVT = supraventricular tachycardia, GER = gastroesophageal reflux, DGE = delayed gastric emptying, ADHD= attention deficit hyperactivity disorder. Lactate measurements listed are in plasma; normnal range 0.5-2.2 mM. Urine organic acids were performed by GC/MS; selected elevated species are listed. Kreb cycle = Kreb cycle intermediates, including fumarate, malate, and succinate.
As is common in patients with other mtDNA disorders, in many of our cases normal lactates and organic acids were obtained at times while the child was clinically stable. Normal once = test performed only once and while the child was stable. In patient 4, a plasma acylcamitine profile revealed a low acetylcamitine only.
In patient 5, organic acids showed increased long chain free fatty acids, 3-hydroxy free fatty acids (saturated and unsaturated C10, 12 and 14), and dicarboxylic acids (C6, 8, & 10); fatty acid oxidation disorders were essentially ruled out by normal palmitate and myristate oxidation rates (M. Bennett, Dallas, Texas), normal enzymatic activities for LCHAD, SCHAD and both long and short chain 1-3-ketoacyl-CoA thiolases,
# molecular testing for the common MCAD mutation and plasma acyl carnitines (showing only a non-specific increase in medium chain species, predominantly unsaturated). Muscle biopsies were performed on quadriceps; selected abnormalities are listed. Citrate synthase is a reference enzyme which when elevated can indicate mitochondrial proliferation.
Low complex 1, 3, and/or 4 refer to abnormal low function of these complexes of the respiratory chain (20-50% of normal activity in each case, except for patient 6). Patient 6 received 3 biopsies at different centers by his parents' request; complex 1 deficiency (1/10th of the 5th % ile) was found by Dr. John Shoffner, Scottish Rite Hospital, Atlanta, while a partial complex 4 deficiency was found by Dr. Richard Haas, University of Califomia San Diego, both on fresh muscle.
As complexes 1, 3 and 4 contain mtDNA-encoded subunits, partial deficiency of each is consistent with a mtDNA mutation. Complex 5 (also containing mtDNA-encoded subunits) was not measured.
Patient 1 [Transient severe cardiomyopathy]. This child had an unremarkable history until at age 8 months a spider bite became infected which was followed by a loss of developmental milestones. At age 1.5 years an apparent viral upper respiratory and gastrointestinal illness with fasting and dehydration progressed to metabolic acidosis, pancytopenia and dilated cardiomyopathy with congestive heart failure. Developmental delay and failure-to-thrive (FTT) were noted at that time. A mitochondrial disorder was suspected and the child received symptomatic treatment and fasting avoidance. All clinical problems resolved within the next few months except for cyclic neutropenia, which resolved before his third birthday. Currently, at age 7 the child is clinically completely normal, including school performance and cardiac function, except for stable and symmetrical growth retardation (height age=4.7 years). The pedigree is shown in FIG. 1 .
Patient 2 [Transient severe cardiomyopathy]. This child presented at age 6 months with severe dilated cardiomyopathy in congestive heart failure. She was medically treated and listed for transplantation, however, her cardiac function markedly improved on strict fasting avoidance and standard medical therapy. At age 4.5 years she has near normal systolic function and possible mild decreased diastolic function. Mild failure-to-thrive also resolved. Intelligence and physical examination are normal except for a decreased muscle bulk. The family history is unremarkable.
Patient 4 [Fasting hypoglycemia]. At the age of 13 months, following 10 days of upper respiratory tract symptoms with decreased oral intake, this child was found to be hypoventilating, gray, staring and limp, progressing rapidly to posturing and coma. Temperature was 34.9° C. and serum glucose was 2.2 mM (40 mg/dl) when paramedics arrived; all symptoms resolved immediately following the administration of a glucose-containing intravenous fluid. A very similar event occurred following an eight-hour overnight fast. A disorder of fatty acid oxidation was postulated and fasting precautions were initiated, including 3-4 hours feedings by day and continuous drip feedings by night. No further episodes have occurred, although the child has not been fasted. Gross motor delay, mild hypotonia and growth retardation resolved. At present, the child is asymptomatic except for asthma, occasional staring spells and rare episodes of profound muscle weakness and flank/leg pain during which the child is unable to bear weight for about 2 hours. Family history is remarkable only for a cystic hygroma and similar episodes of muscle weakness, generalized fatigue and an inability to walk in his now 5 year old brother. Their normal parents are not consanguineous.
Patient 9 [Mental retardation/spasticity]. This child has a static encephalopathy with profound mental retardation, spastic quadriplegia, strabismus and nystagmus. Signs or symptoms of non-neuromuscular tissue dysfunction have been absent. Diagnostic evaluation revealed optic atrophy and leukodystrophy. The family history is unremarkable.
Patient 10 [Neonatal severe multi-system disease]. This child presented at birth with esophageal atresia and a severe metabolic acidosis refractory to standard treatment. He was transported to the Childrens Hospital Los Angeles facility in severe cardiogenic shock at age 11 days and started on ionotropes for a hypertrophic cardiomyopathy, peritoneal dialysis for acute renal failure and specific therapy for mitochondrial failure. The latter was designed in order to reverse and prevent catabolism and consisted of a continuous infusion of glucose at 10-12 mg/kg/min, insulin at about 0.1 units/kg/hr (titrated to maintain serum glucose between 5-10 mM=90-180 mg/dl), and protein at 1.0 g/kg/d. On this treatment, the anion gap (30 to 14 mM), plasma lactate and renal function normalized, and cardiac function greatly improved within one week. Of note, the lactate remained elevated for several days following the return of normal circulation. The child remained ventilator dependent with chronic lung disease and suffered several cardiac arrests; the last one being lethal at age 4 months. The family history is remarkable for a previous male and female sibling with very similar manifestations (including organic acids and muscle electron transport chain activities in one), who died at ages 3 and 5 months despite intensive support.
Patient 12 [Reversible multi-system disease]. This child was delivered at 28 weeks gestation following a pregnancy reportably complicated by cocaine and ethanol exposure, although facial morphology appears normal. However, except for chronic lung disease and brief mixed apnea, there were no other complications related to prematurity. The child's first year was dominated by severe symmetrical FTT and gastrointestinal dysfunction; a fundoplication/gastrostomy and pyloroplasty were performed for gastroesophageal reflux (GER) and pyloric stenosis. Additional problems included complex partial seizures, hypotonia and cleft palate. All of these conditions either resolved or were surgically repaired, and presently at age 3 years her only problem is mild global cognitive delay. Although she remains very small (height and weight age=17 and 13 months, respectively), she now demonstrates a normal growth rate for age. The child was adopted, although her 4 year old maternal half-sister was evaluated and found to have symmetrical FTT with a normal current growth rate, moderate developmental delay, strabismus, and resolved GER.
EXAMPLE 3
Methods
Subjects. The experimental group consisted of 67 unrelated children ascertained over a five year period (1994-1999) from the clinical genetics practice of Dr. Richard Boles at Childrens Hospital Los Angeles. All qualifying children were retrospectively recruited based upon the presence of neuromuscular and/or multi-system system disease, an elevated body fluid lactate concentration (usually in plasma and often minimally elevated, >2.0 mM or 18 mg/dl) and the absence of another diagnosis despite an extensive evaluation. This latter evaluation was tailored to each specific child, but always included a high resolution karyotype, urine organic acids, plasma amino acids, Southern blotting for large rearrangements, and PCR for 10 known point mutations (Wong and Senadheera (1997) Clin Chem 43:1857-61). An additional 14 children that would have qualified were excluded from the study due to the absence of available DNA from a blood sample. No cases were included if ascertainment was based on the referral of a sample to the laboratory for the purpose of mtDNA analysis.
The control group consisted of 103 unrelated individuals, of which 76 were children of all ages, with definitive diagnoses of non-mitochondrial disorders, including 58 individuals with phenylketonuria (PKU) diagnosed on newborn screening, and 33 and 12 individuals diagnosed by molecular assays with spinal muscular atrophy and Duchenne muscular dystrophy, respectively. There was no reason to believe that any of these conditions were related to mtDNA sequence variations. This study was approved by the CHLA Institutional Review Board.
Molecular Assays. Total DNA was extracted from blood or hair root and PCR and temporal temperature gradient gel electrophoresis (TTGE) were performed as previously reported (Zoller and Redilla-Flores (1996) Temporal temperature gradient gel electrophoresis of cystic fibrosis samples on the Dcode system. Bio-Rad Laboratories, US/EG Bulletin 2103; Chen et al. (1999) Clin Chem 45:1162-7; Higashimoto et al. (1999) Clin Chem 45:2005-6; Wong and Lam (1997) Clin Chem 43:1241-3). Peripheral blood was assayed in all cases and controls. When available, hair was assayed in the probands and blood and/or hair was assayed in their first degree relatives. The mtDNA control region was divided into 3 segments for TTGE analysis (FIG. 2 ). TTGE was a relatively novel heteroduplex detection assay which has been shown to be very sensitive in the detection of mtDNA heteroplasmy (including 60 of 60 known cases positively identified (Chen et al. (1999) Clin Chem 45:1162-7; Chen et al. (1997) Am J Hum Genet 61:A306 (abstract)). TTGE was also very specific as each heteroplasmic mutation or polymorphism demonstrated a reproducible and distinct band pattern (FIG. 3) (Chen et al. (1999) Clin Chem 45:1162-7). Heteroplasmy could be detected with proportions as low as about 5% (supra). Ethidium bromide stained TTGE gels were visualized under UV light and imaged with a digital CCD gel documentation system. Percent heteroplasmy for each sequence variant could readily be estimated by the relative intensities of the bands. These measurements could be taken by eye or Gene scan analysis with fluorescent labeled primers and employing the binomial theorem, with results closely agreeing those obtained by denaturing high performance liquid chromatography (Transgenomic WAVE™ DNA Fragment Analysis System, Omaha, Nebr., data not shown).
For quality assurance, every gel was run concurrently with 1-3 positive controls (known heteroplasmic samples). All assays were repeated starting with the original extracted DNA sample in every case in which heteroplasmy was found in order to exclude PCR artifacts. Pseudogenes were not amplified in any of the segments as determined by the absence of any PCR product (FIG. 3) using primers listed in Table 2 with total DNA extracted from rho negative cell culture (cells lacking any mtDNA (Chomyn et al. (1991) Mol Cell Biol 11:2236-44), kindly provided by Anne Chomyn at CalTech). Contaminated (i.e. blood transfused) samples were easily detected by the presence of multiple bands (>4) present in multiple mtDNA segments. One such sample was thus identified and removed from this study after confirmation of contamination by HLA typing. Cyclosequencing was performed in all cases with multiple bands seen on TTGE either from a single band cut out from the gel or directly from the original samples, using a dye terminator Cyclosequencing kit (Applied Biosystems) and an Applied Biosystems ABI 373A DNA Sequencer. Haplogrouping was determined by restriction digest and sequencing part of the control region as previously reported (Torroni et al. (1996) Genetics 144:1835-50).
TABLE 2
Segment
mtDNA Regions
Nucleotides
Size (bp)
Primer Sequences (5′-3′)
Ta
Ti-Tf, Tr
7S
Control region
15987-16509
523
upper
CACCCAAAGCT
53
50-62, 3.0
(includes HV1);
AAGATTCTAA
tRNA-Pro
(SEQ ID NO:1)
lower
AGGCTTTATGAC
CCTGAAGTA
(SEQ ID NO:2)
7Sb*
Control region
16200-16509
310
upper
TCCACATCAAAA
53
56-64, 3.0
CCCCCCCCC
(SEQ ID NO:3)
lower
AGGCTTTATGAC
CCTGAAGTA
(SEQ ID NO:4)
7Sc*
Control region
15852-16155
304
upper
TCTCCCTAATTG
58
50-59, 3.0
AAAACAAAA
(SEQ ID NO:5)
lower
TGGATTGGGTTT
TTATGTACT
(SEQ ID NO:6)
CSB
Control region
16407-560
723
upper
CCTCCGTGAAAT
53
54-61, 3.7
(includes HV2)
CAATATCCC
(SEQ ID NO:7)
lower
AAACTGTGGGG
GGTGTCTTTG
(SEQ ID NO:8)
F
Control region
500-1190
691
upper
CCCATCCTACCC
56
55-59, 1.0
tRNA-Phe;
AGCACACAC
12S-rRNA
(SEQ ID NO:9)
lower
GATATGAAGCA
CCGCCAGGTC
(SEQ ID NO:10)
TTGE conditions for each segment were determined by computer simulation (MacMelt, Bio-Rad Laboratories) and adjusted by experimentation. T a is the annealing temperature for PCR. T 1 , T f , and T r are the initial, final, and ramp rate temperatures for TTGE.
*A common length heteroplasmy at nt 16184 in the 7S segment occasionally complicated the search for potential additional point heteroplasmies elsewhere in the same segment. These cases were each evaluated by TTGE in two additional segments ‘7Sb’ and ‘7Sc’ which excluded the site of the length heteroplasmy by moving one of the primer sites to a conserved sequence area close to the homopolymeric cytosine tract.
EXAMPLE 4
Results
Distinct TTGE band patterns consistent with the presence of a heteroplasmic single nucleotide substitution (‘point heteroplasmy’, FIG. 3) were found in the 7S fragment in 10 of 67 children in the experimental group and in none of the 103 individuals in the control group (p<0.001). In the 8/10 cases in which sufficient DNA was available, sequencing confirmed the presence of at least one point heteroplasmy in hypervariable region 1 (HV1, Table 1, FIG. 2; one mutation was outside of the region commonly referred to as HV1). TTGE analysis in the CSB fragment was consistent with point heteroplasmy in 1 case and in 0 controls; and sequencing revealed a heteroplasmic nucleotide in HV2 (Table 1, FIG. 2 ). In each case, these base substitutions were previously identified in homoplasmic form as polymorphisms (found in normal individuals) (Kogelnik et al. (1996) Nuc Ad Res, 24:177-9; Opdal et al. (1998) Acta Paediatr 87:1030-44), and many of these polymorphisms have been encountered upon sequencing control individuals in the laboratory (data not shown). Elsewhere in the mtDNA control region, point heteroplasmy was absent in all patients and controls. Multiple cases in both the experimental and control groups were revealed by TTGE and confirmed by sequencing to have polymorphic length variants (length heteroplasmy). Most of these length variants have been previously reported (Bendall and Sykes (1995) Am J Hum Genet 57:248-56; Torroni et al. (1994) Am J Hum Genet 55:760-76), although rare or unique variants were also found in at least 2 patients and are the subject of continuing investigation.
In order to determine whether the observed point heteroplasmic variants were inherited or somatic mutations, samples were assayed from the family members of patients. Consistent with maternal inheritance of mtDNA, in each case in which samples from the mother (patients 4, 6-10, 13), full sibling (patients 4, 6, 9, 10, 13) or maternal half sibling (patient 12) were available, the identical point heteroplasmy was identified by TTGE and/or sequencing. Samples were available from the fathers of patients 1, 4, 6, 7, 9 and 10 and the specific nucleotide variation seen in the proband was absent in each. A distinct HV1 point heteroplasmy was noted in the father of patient 10. DNA was not available from any family members of the child with HV2 heteroplasmy.
Direct sequencing of the patient or family samples rarely reveals heteroplasmy due to low proportions of the minority sequence (often about 5-25% as estimated by TTGE). The methods employed herein, which involve sequencing of DNA derived from different gel bands, readily reveals the two sequences constituting the heteroplasmic nucleotide identified by TTGE, but this does not exclude the presence of other heteroplasmic nucleotides within the same segment. Careful review of the HV1 sequences revealed probable point heteroplasmy in additional nucleotides in many cases, but not in controls. A second heteroplasmic nucleotide, suspected by sequencing, was confirmed using PCR/allele specific oligonucleotide (ASO) analysis (Wong and Senadheera (1997) Clin Chem 43:1857-61) in patients 8 and 9 (Table 1). In the latter, further PCR/ASO analyses in the asymptomatic (by history and neurological examination) mother and 11 year old sister revealed the presence of point heteroplasmy at both nucleotides in the mother, and at one site only in the sister (16288T-C). In addition, a third point heteroplasmy was found in the mother, which was homoplasmic for the polymorphism (16278T) in our patient by PCR/ASO. At each heteroplasmic loci, the proportions of each variant were widely different in each family member (and in individual hair roots within each individual), such that almost all direct sequences revealed homoplasmy (single mtDNA sequence present) for one or the other sequence variant.
In conclusion, reported herein is a novel association of predominately intermittent and non-progressive disease, biochemical signs suggestive of mitochondrial dysfunction, and maternally-inherited mtDNA-CR point heteroplasmy. Pathology is likely mediated through a novel disease mechanism. This disorder is apparently not rare as it was identified in 1/6 children with idiopathic neuromuscular or multi-system disease and an elevated body fluid lactate, a paradigm which is frequently seen in tertiary practice. With highly variable manifestations, this condition(s) will likely be encountered by clinicians in a variety of specialties treating children. Recognition is important, not only to provide the family with a specific diagnosis that in cases without severe neuromuscular disease appears to carry a relatively favorable prognosis, but in many cases to provide appropriate treatment, especially regarding the avoidance of fasting.
The foregoing is illustrative of the present invention, and is not to be construed as limiting thereof. The invention is defined by the following claims, with equivalents of the claims to be included therein.
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#21 | A method of screening a subject for mitochondrial dysfunction comprises detecting the presence or absence of single nucleotide changes in a hypervariable region of the mitochondrial DNA of said subject, the presence of such changes indicating that said subject is afflicted with or at risk of developing mitochondrial dysfunction. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to suturing and sewing devices. In particular, the present invention concerns hand operable apparatus for facilitating traditionally manual suturing/sewing operations, in both medical and non-medical environments.
Traditionally, suturing in the medical profession has been a wholly manual procedure. Typically, adjacent edges of tissue layers to be joined are clamped or otherwise held in closely adjacent or overlapping relation. A needle and attached thread are then repeatedly passed through the adjoining tissue layer edges. The latter step is effected by securing the needle in a finger actuated pliers-like clamp and pushing the needle into the tissue, allowing the pointed distal end to protrude from the opposite side. Next, the protruding distal end of the needle is grasped and the needle is pulled completely through the tissue. Depending on the stitch being utilized, the needle may then be reoriented to repeat the procedure in the opposite direction, or returned to the starting side (with the thread passing over the seam line), for a repeat of the procedure. Advantageously, in the case of a double pointed needle (with the thread attached at a midpoint between the pointed ends), the needle can be passed back and forth through the tissue, from one side to the other, without an end-to-end reorientation of the needle. With all of the above-mentioned variations, the steps are repeated to create the required number of stitches, and finally the ends of the thread are knotted to complete the suture.
Performance of the above-described traditional techniques typically requires the use of two hands. In many instances, it is necessary that the physician have one hand free for other purposes during the suturing procedure, in which case it is necessary to utilize the hand of an assistant in order to pull the needle through the tissue and pass it back to the doctor. Particularly when a large number of stitches are involved, suturing procedures become tedious, time consuming and fatiguing, to the obvious detriment of both the patient and the attending care givers. Moreover, over the long term, health care personnel performing suturing procedures on a regular basis may experience repetitive motion stress injury.
The traditional procedures utilized for medical suturing are not unlike the traditional manual techniques for sewing fabrics and the like. Like medical suturing, sewing by hand requires considerable dexterity. This may present a barrier to certain persons desiring to undertake such activity. For example, sewing by hand is a popular pastime activity amongst elderly persons, yet many are unable to perform the intricate hand work that is required due to arthritis and/or peripheral neuropathy disorders.
Numerous attempts have been to devise hand tools for improving upon the traditional completely manual suturing/sewing techniques.
Saunders et al. U.S. Pat. No. 1,131,163 and Steedman U.S. Pat. No. 1,155,378 disclose suturing devices comprising a pair of needle holders between which an arcuate needle is passed. Handles are provided for pivoting the needle holders together manually, and a separate movement of the handles is required in order to engage one of the holders with the needle, and release the other. Needle hand-off is performed when the holders are spaced apart from each other. A locking mechanism is provided for ensuring that the needle is not released from one holder unless the other holder is in position to receive the opposite end of the needle.
Stenson U.S. Pat. No. 4,236,470 discloses a pair of arms pivoted together at one end and having needle holders at their opposite ends movable into and out of proximity with each other to effect the hand-off of a double pointed needle. The main embodiment has separate spring loaded triggers for manually actuating the opening and closing of the respective needle holders. A second embodiment discloses a single trigger for simultaneously releasing the needle from one holder and engaging it with the other.
Weintraub et al. U.S. Pat. No. 4,635,638 teaches power (pneumatic) actuation of a pair of needle gripping members mounted on rectilinearly extendable and retractable arms. Separate switches are provided for each arm and associated gripping member. By advancing the switches through a series of positions, the arms are first extended, and then the gripping jaws are actuated to close; a reverse movement of the switches causes the associated gripping jaw to open, and then retraction of the associated arm.
Nolan et al. U.S. Pat. No. 5,480,406 ("the '406 patent") is a U.S. Surgical Corp. patent referring to its commercially available Endo Stitch device. The patent also mentions related U.S. Surgical patent applications (now abandoned) directed to the device. The Endo Stitch device has a pair of manually operated handles serving to open and close a pair of needle holding jaws located at the end of an elongated arm. Each jaw incorporates a needle holding recess, and a needle is passed from one to the other. A manually rotatable actuating member with a pair of tabs for finger manipulation serves to simultaneously engage a needle in one holder and release the needle from the other holder, once the jaws have been closed by operation of the separate handle. A safety mechanism is provided to prevent the release of a needle gripping holder unless the jaws are in their closed position such that the other holder can grasp the needle.
Smith U.S. Pat. No. 2,601,564 discloses a suturing device having two arms which are independently, rectilinearly extensible and retractable to effect a needle hand-off. The arms comprise tubular members with grooves in their respective ends. Rods are rotatable within the tubes in order to release and grip the needle. Respective spring-loaded levers move first longitudinally to extend the arms, then vertically to effect rotation in order to clamp the needle.
Melzer et al. U.S. Pat. No. 5,389,103 discloses an endoscopic suturing device with one stationary and one movable mouthpiece for passing therebetween a double pointed needle. The movable mouthpiece is moved linearly with respect to the stationary mouthpiece by way of concentric tubes. The device is semi-automatic. A foot switch connected with a pneumatic power source opens and closes the jaws of the stationary mouthpiece. The jaws of the other mouthpiece are spring-loaded to grip and release the needle.
In summary, the above references disclose suturing devices with various means for effecting transfer of a needle back and forth between gripping elements movable with respect to each other. Some of the devices are completely manual, while others include power actuation. The completely manual devices require multiple hand motions, and the exertion of considerable actuating forces, thus leading to hand fatigue. While the powered devices would apparently reduce the required manual effort, those devices still require inconvenient coordinated movements and/or switch actuations to effect needle hand-off. Moreover, the known powered devices in particular appear susceptible to inadvertent needle droppings due to premature needle release.
Published U.K Patent Application GB 2 260 704 A discloses a laparoscopic suturing device with an overall structure which is generally similar to the U.S. Surgical Endo Stitch device. In the embodiment shown, a pair of jaw elements are pivoted to each other at the end of an elongated arm. Each jaw element has a needle retaining recess. A manual trigger is squeezed to first bring the jaws together and then actuate respective securing means to release the needle from one jaw and grip it with the other. The document mentions the possibility of powered actuation of the securing means by hydraulic, pneumatic or electrical (e.g., solenoid) means. While this device apparently would avoid the need for discrete hand movements for bringing the jaws together, then actuating the securing means to effect a needle transfer (as required by the Endo Stitch device), the disclosed utilization of a single motive force (either manual or powered) for actuating these tool motions would likely cause difficulties in controlling both the movement of the jaws and the needle gripping/release actions. Moreover, the disclosed design of the illustrated dual purpose mechanical linkage is rather conceptual and appears susceptible to operability problems.
SUMMARY OF THE INVENTION
In view of the foregoing it is a principal object of the present invention to provide a relatively simple and reliable hand operable tool that effectively minimizes the amount of time, effort and dexterity required to perform suturing and sewing operations.
It is a particular object of the present invention to provide a semi-automated suturing/sewing device that does not require separate hand motions in order to first bring a pair of needle holders into a needle transfer position and then to effect a needle transfer.
It is a further object of the invention to provide a simple design that avoids the above-mentioned required separate hand motions, yet retains a high degree of controllability.
It is yet another objective of the present invention to provide a semi-automatic suturing device with a simple and effective safety mechanism for preventing inadvertent needle drops due to premature needle holder release.
These and other objects are achieved by a semi-automatic suturing/sewing device in accordance with the present invention. The device has a hand graspable tool body. A pair of needle holders are operably connected to the body for movement with respect to each other, into and out of a preset needle transfer position, by application of manual force. Each needle holder has a releasable needle gripping element. A power actuator assembly provides motive forces, separate from the manual force, for actuating the gripping elements to move between respective needle gripping and release positions, and for providing a predetermined gripping force of said gripping elements in their respective gripping positions. An electronic control mechanism is provided for controlling operation of the power actuator assembly. The mechanism comprises a detector for producing a first signal when the needle holders have been moved to the needle transfer position. The control mechanism actuates the power actuator assembly in response to the first signal, to automatically alternatingly hold the gripping elements in their gripping positions and move the gripping elements to their release positions, in order to effect successive needle transfers from one needle holder to the other.
These and other objects, advantages and features of the present invention will be readily apparent and fully understood from the following detailed description of the preferred embodiments, taken in connection with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a semi-automatic suturing/sewing device in accordance with the present invention, having a hand graspable tool body (with arms thereof pivoted apart), and a separate control box.
FIG. 2 is a top view of the tool body shown in FIG. 1, with the arms pivoted together to place a pair of needle holders in a needle transfer position.
FIG. 3 is a side elevational view of a primary arm of the hand graspable body, clearly showing a slot for receiving a secondary (smaller) arm pivotally attached thereto.
FIG. 4 is a close-up partial perspective view illustrating the vise-like needle holders of the inventive device.
FIG. 5 is a horizontal cross-sectional view taken on line 5--5 in FIG. 3.
FIG. 6 is a cross-sectional view taken on line 6--6 in FIG. 2.
FIG. 7 is a schematic depiction of the circuitry and electro-mechanical componentry of the control box shown on FIG. 1.
FIGS. 8A-8F are partial elevational views illustrating sequential stages of back-and-forth needle transfer operations with the inventive device.
FIG. 9 illustrates a second self-contained embodiment of the invention, wherein the power actuation and electronic control components are contained within the hand graspable tool body.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1, a semi-automatic suturing/sewing device in accordance with the present invention includes a hand graspable tool body 1 and a separate control box 3. Tool body 1 comprises two elongated arms which are pivotally mounted to each other, a primary arm 5 and a secondary (smaller) arm 7. Each of arms 5, 7 carries at its end a vise-like needle holder 9,9' comprising a releasable needle gripping element in the form of a movable vise jaw 11, 11'. As illustrated in FIG. 1, needle holder 9 is in an extended, needle release position, spaced apart from an abutting clamp surface 13. Needle holder 9' is in a retracted needle gripping position, wherein jaw 11' is held tightly against a corresponding abutting clamp surface 13'.
As best seen in FIGS. 2-3, secondary arm 7 is pivotally mounted to primary arm 5 by a pivot pin 14, to move, by hand force, into and out of a channel 15 defined between a pair of spaced flanges 17 extending longitudinally along one side of a relatively wide proximal part of primary arm 5. Preferably, as seen in FIG. 5, arm 7 is biased to pivot away from arm 5 to a separated position established by abutting stop surfaces of the arms. As shown, the bias is provided by a torsion spring 19 mounted about pivot pin 13. The separated position of the arms allows a needle held in the needle holder of the other arm to be pressed through tissue or other material until the point of the needle protrudes from the other side. Pivoting the arms together positions needle holders 9, 9' in close proximity to each other, whereupon the released needle holder is automatically moved to a gripping position clamped down on the protruding end of the needle. Shortly thereafter, the gripping holder on the other side is caused to open and thereby release the needle. In this manner, a needle transfer from one to the other needle holder can be carried out, thus allowing the needle to be pulled through the tissue or other material with minimal hand movements and exertion, and without the necessity of a second hand.
The occurrence of an automatic needle transfer, upon moving holders 9,9' into close proximity with each other, is initiated by a proximity switch assembly including cooperative elements mounted on arms 5 and 7, respectively. As seen in FIGS. 3 and 5, mounted generally flush within channel 15 is a conventional spring-biased push-button type on-off switch 21. As seen in FIGS. 1 and 2, mounted at a corresponding location on arm 7 is an actuator pin 23 serving to depress and thereby actuate switch 21 as secondary arm 7 pivots into proximity with primary arm 5. The protruding distance of pin 23 is preferably made adjustable in order to allow adjustment of the relative positions of needle holders 9, 9' at which needle transfer occurs. This can be accomplished by various known means such as providing pin 23 as an advanceable set screw.
Referring now to FIG. 4, the structure of needle holders 9, 9' is clearly seen, with needle holder 9 gripping a bowed double pointed needle 25 having a thread 26 attached at its midpoint. Releasable gripping jaws 11, 11' are preferably cast of or machined from surgical steel or the like, together with an elongated shank 27, 27' mounted for longitudinal movement within a respective one of arms 5, 7. The gripping faces of jaws 11, 11' are preferably knurled with a small diamond shaped pattern for securely gripping needle 25, as are the opposing clamp surfaces 13, 13' provided on the ends of arms 5,7. Preferably, tool body 1, including arms 5 and 7, will be molded of lightweight high impact plastic material, or the like. As shown, plates of surgical steel or other wear resistant material can be mounted on the ends of the plastic arms in order to provide clamp surfaces 13, 13'.
The illustrated arrangement of vise-like needle holders 9, 9' works perfectly well for gripping and allowing the transfer of various known types of needles, e.g., double point and single point, straight and bowed. Advantageously, in the case of a single point needle with the thread trailing from the tail end, the tool may be utilized with gripping jaws 11, 11' pointing downwardly, whereby trailing thread 26 will fall freely away from shanks 27, 27' as the tool is reoriented between stitches to redirect the needle point. Although the illustrated embodiment utilizes a simple arrangement for pivoting arms 5, 7 together in a single plane, it will be appreciated that for a bowed needle some advantage could be gained by providing a hinge arrangement that would provide the arms with a compound motion allowing the approaching needle holder to follow the arc of the needle shank.
Referring now to FIGS. 5 and 6, the structure of tool body 1 is further described. The distal ends of arms 5 and 7 are configured as blocks 31, 31' defining respective slot-like guide ways 33, 33' slidably receiving elongated jaw shanks 25, 25'. The jaw shanks extend beyond blocks 31, 31' in the proximal direction, into respective return spring sections 35, 35'. Each return spring section comprises a coil compression spring 36, 36' retained within a channel 37, 37' and abutted at its proximal end against a bracing wall 39, 39'. The end of each jaw shank 25, 25' is connected to a flexible control cable 41, 41' extending out of tool body 1 and to remotely located control box 3. Each shank 25, 25' carries a flange 43, 43' providing a push surface abutting with the distal end of the associated spring. By means to be described, control cables 41, 41' are drawn in the proximal direction, against the bias of springs 36, 36', to pull jaws 11, 11' into gripping engagement with abutting clamp surfaces 13, 13', and then released, in an alternating fashion. Rapid return of the jaws to a release position is assured by spring sections 35, 35'.
In addition to push-button switch 21, primary arm 5 carries a second switch 45 of conventional construction serving to initialize operation of the device. Signal wires 44, 44' from each of the switches extend out of tool body 1 to control box 3.
Referring now to FIG. 7, it can be seen that control box 3 houses a power actuator assembly and an electronic control mechanism for controlling operation of the same. The power actuator assembly comprises a pair of power solenoids 47, 47' which are operably attached to the ends of control cables 41, 41'. In this manner, the in-and-out throw of each solenoid core 48, 48' is translated into a corresponding movement of the respective gripping jaw 11, 11' between its gripping and release positions. In addition, during activation of the solenoids, a strong gripping force, e.g., 40 lbs, is imparted to the needle holders 9, 9', In practice, the ideal gripping force level will depend on the particular sewing/suturing operation.
The electronic control mechanism preferably comprises a simple digital processor 49 which receives signals from switches 21 and 45 over lines 44, 44', and in response to those signals outputs a pair of control signals to a corresponding pair of electrical relays 51, 51'. Digital processor 49 receives conditioned low voltage DC power from a power supply 53 which receives and converts AC line voltage upon activation of power switch 52. On receipt of an ON signal from processor 49, relays 51, 51' close their contacts to supply the AC line voltage directly to the corresponding solenoids 47, 47', whereby the solenoid coils are energized causing retraction of the cores 48, 48'. The solenoid coils remain energized to impart a strong gripping force to the needle holders so long as the respective signals from processor 49 remain ON. When the signals switch to OFF, the relays are switched to deactivate the respective solenoids, whereupon the gripping jaws 11, 11' are caused to quickly move to an extended release position, under the bias of corresponding springs 36, 36'.
The preferred logic control of digital processor 49 is now described in greater detail. Upon actuation of initialization switch 45, the signal sent to processor 49 causes the processor to output an ON signal to one of relays 51, 51', and an OFF signal to the other. In this manner, e.g., gripping jaw 11 of primary arm 5 is caused to be held in its gripping position, thus securely holding a needle pre-positioned in needle holder 9. At the same time, gripping jaw 11' of secondary arm 7 remains in its release position. This operative position of the two jaws is maintained until a trigger signal is received from proximity switch 21, indicating that arms 5 and 7 have been pivoted together to bring needle holders 9, 9' into the needle transfer position. On receipt of a trigger signal, the output signals to relays 51, 51' flip-flop, causing gripping jaw 11 to move to its release position, and gripping jaw 11' to move (and be held in) its gripping position.
In order to prevent accidental needle droppings due to premature needle release, it is preferred that the logic control circuit introduce a time delay before switching its output signals from ON to OFF. More specifically, an OFF signal to one of the relays should only be generated after a predetermined time period following generation of a corresponding ON signal to the other relay. In this manner, it can be assured that release by one of needle holders 9, 9' will not occur before the needle has been securely gripped at its opposite end by the other. Programmability is desirable in order to allow this time delay to be preset at an empirically determined optimum value. Programmability is also desirable in order to allow introduction of a time delay between receipt of a trigger signal from proximity switch 21 and the generation of the corresponding output signals to the relays 51, 51'. This will allow the user to tailor the responsiveness of the device to his/her particular preferences.
It will be readily appreciated that a digital processor having the above-described functionality may be constructed from individual circuit components, as a special purpose integrated circuit chip and/or a suitably programmed general purpose computer. In a prototype device constructed by the inventors, a general purpose processor available from the Kayence company of Osaka, Japan (model no. KV-10R) was used with success. The processor was programmed using an associated software kit (model no. KV-3) and an IBM-type personal computer. Obviously, a special purpose circuit board or chip would be preferred for a commercial embodiment.
Referring now to FIGS. 8A-8F, the transfer of bowed double pointed needle 25 from arm 5 to arm 7, and back to arm 5, is illustrated in sequence. In FIG. 8A, needle 25 is held securely in needle holder 9, and arms 5 and 7 are spaced (pivoted) apart from each other. In FIG. 8B, the arms have been pivoted into the needle transfer position, with holders 9 and 9' in close proximity to each other. At this point, actuation of the proximity switch 21 causes gripping jaw 11' of needle holder 9' to move to its needle gripping position, as shown in FIG. 8C. As also seen in FIG. 8C, gripping jaw 11 remains in its gripping position for a predetermined time period after gripping jaw 11' reaches its gripping position, so as to prevent inadvertent needle droppings. In FIG. 8D the needle transfer has been completed, with gripping jaw 11 returned to its release position. In FIG. 8E, arms 5,7 and corresponding gripping jaws 11, 11' are back in the position shown in FIG 8C, as needle 25 is transferred back to arm 5. In FIG. 8F, the return needle transfer has been completed.
A second "self-contained" embodiment of the present invention is illustrated in FIG. 9. This embodiment differs from the first embodiment in that electromechanical componentry corresponding to that housed within control box 3 (of the first embodiment) is contained within a modified hand graspable tool body 101, and control cables 41, 41' are dispensed with. As between the two embodiments, like elements are correspondingly numbered, and except as otherwise noted, the structure and operation is essentially the same.
In the self contained embodiment, solenoids 147, 147' are mounted within respective arms 105, 107, directly in line with respective jaw shanks 125, 125'. The core 148, 148' of each solenoid is directly connected with the proximal end of the corresponding jaw shank 125, 125', so as to move the gripping elements 111, 111' between their gripping and release positions. In addition to solenoid 147, primary arm 105 houses a pair of relays 151, 151', a processor 149, and a power supply 153. Power supply 153 could be provided in the form of a battery pack to allow completely portable operation.
Obviously, in the second embodiment, component miniaturization takes on greater importance. Toward this end, it is preferred that the processor of the second embodiment be provided in the form of a microprocessor chip, and that the other components be miniaturized and integrated to the extent permitted by the state of the art. In this regard, a limiting factor is that the solenoids (and power supply therefor) must have a capacity to allow reliable generation of gripping forces sufficient to securely hold a needle in the intended suturing or sewing application.
The present invention has been described in terms of exemplary and presently preferred embodiments thereof. Numerous other embodiments, modifications and variations within the scope and spirit of the appended claims will occur to those having ordinary skill in the art, upon a review of this disclosure. For example, it is not necessary that the movement of the needle holders be pivotal into and out of a needle transfer position; the motion could be rectilinear. Nor is the invention limited to needle holders in the form of vise-like clamps. Moreover, it will be appreciated that various power actuation and detector mechanisms could be provided. For example, the power actuation could be pneumatic or hydraulic instead of electromagnetic. In addition, the detector could comprise various known proximity-type switches, e.g., optical or magnetic switches.
In particular, it will be appreciated that the configuration of the device may vary considerably depending upon the uses to which the device will be put, and the manufacturing methods therefor. In this regard, the principles of the invention may, e.g., be applied to provide semi-automatic laparoscopic suturing tools, with small (needle holder carrying) arms pivoted at the end of an elongated shaft insertable into a trocar or the like. | A semi-automatic suturing device passes a single or double pointed needle back and forth between two needle holders in order to avoid the need for manually grasping and otherwise manipulating the needle after it has passed through body tissue or other material being sewn. The needle holders are provided in the form of respective sets of vise-like jaws on a pair of arms which are pivotally attached to each other. The holders are thereby manually movable into and out of proximity with each other. The needle holding jaws are automatically alternatingly actuated to open and close when they are pivoted into proximity with each other, such that a hand-off of the needle can occur. Actuation of the needle gripping jaws is power driven, e.g., by a solenoid, and automatically initiated by a proximity switch which detects when the jaws have been brought together. Logic circuitry ensures that one set of needle gripping jaws does not release the needle until the other holder has closed to grip the opposite end of the needle. In this manner, accidental needle droppings are avoided. | 0 |
BACKGROUND OF THE INVENTION
The invention relates to a system for reading magnetic information, comprising:
a read head provided with a magnetoresistive bar whose electric resistivity varies when it is subjected to a magnetic field variation, said bar having a first and a second terminal and being intended to be traversed by a bias current of a predetermined value,
a first amplifier comprising a first and a second transistor arranged as a differential pair, with their bases connected to the first and the second terminal, respectively, of the magnetoresistive bar and at least one collector constituting an output of the first amplifier.
Such a reading system is described in the article "Preparing the preamplifier for the brave new world of MR heads", published in DATA STORAGE in April 1996. In this reading system, a coupling capacitor ensures, within the amplifier, a decoupling of the DC component of the signal which is present at the terminals of the magnetoresistive bar. This coupling capacitor is arranged between the emitters of the first and second transistors. The first amplifier has a passband which is limited by a low cut-off frequency and a high cut-off frequency, which passband must be as large as possible. Here, the low cut-off frequency is, in a first approximation, of the order of the inverse value of the product between the value of the coupling capacitor and the value of the resistance, viewed from the emitters of the transistors. As this resistance typically has a value of the order of about ten Ohms, a considerable value is to be given to the coupling capacitor for obtaining an acceptable value of the low cut-off frequency. If it is desired to obtain a low cut-off frequency FO of the order of megahertz values, the coupling capacitor must have a value of the order of about ten nanofarad, which is very difficult to realize in an integrated form. The use of an external capacitor induces the creation of parasitic inductances and resistances which are difficult to control and are detrimental to the satisfactory operation of the system, particularly at high frequencies, and also disturb the symmetry of the amplifier, which degrades its common-mode reject rate.
It is possible to replace the coupling capacitor mentioned above by two capacitors, referred to as decoupling capacitors, each arranged between the base of one of the transistors and one of the terminals of the magnetoresistive bar. In such an amplifier, the low cut-off frequency will be, in a first approximation, of the order of the inverse value of the product between the equivalent value of the two series-arranged decoupling capacitors and the base resistances of the transistors. As such a resistance is of the order of a hundred times larger than the resistance viewed from the emitters, the value of the decoupling capacitors used in such an amplifier may be, for the same low cut-off frequency FO of the order of megahertz values, of the order of a hundred times smaller than that of the coupling capacitor present in the known reading system. This leads to a value of the order of about a hundred picofarad, which remains difficult to realize in an integrated form.
SUMMARY OF THE INVENTION
It is an object of the invention to remedy this drawback by providing a reading system whose architecture allows a considerable reduction of the value of the decoupling capacitors without having to increase the value of the low cut-off frequency.
According to the invention, a system for reading magnetic information as described in the opening paragraph is characterized in that the system also comprises:
a second amplifier comprising a third and a fourth transistor arranged as a differential pair, with their bases connected to the first and the second terminal, respectively, of the magnetoresistive bar and at least one collector constituting an output of the second amplifier,
a first and a second capacitor having equal nominal values, the first capacitor being arranged between the base of the first transistor and the first terminal of the magnetoresistive bar, the second capacitor being arranged between the base of the fourth transistor and the second terminal of the magnetoresistive bar, and
an analog adder having a first input connected to the output of the first amplifier, a second input connected to the output of the second amplifier and an output intended to supply a signal which is representative of the sum of the values of the signals received at the first and second inputs.
The fact that the first and second capacitors each act on a single input of one of the amplifiers, as well as the splitting of the impedance obtained by arranging the first and second amplifiers in parallel allows a reduction of the value of the first and second capacitors with respect to the value of the decoupling capacitors described above. It will hereinafter be demonstrated that the reduction factor is minimally of the order of four with respect to the value of the decoupling capacitors mentioned above. The value of the first and second capacitors is then several tens of picofarads, which can be realized in an integrated form.
The splitting of the amplification function by means of the first and second amplifiers induces the necessity of combining the outputs of these amplifiers, which function is realized by means of the analog adder. Numerous embodiments of this adder are possible. One embodiment of the invention provides a system for reading magnetic information as described above, which is characterized in that the analog adder comprises:
a first and a second module of the transconductance type, each having an input constituting one of the inputs of the adder and an output intended to supply a current which is proportional to the value of a voltage received at its input, and
a resistor having one terminal connected to a fixed voltage terminal and another terminal connected to the outputs of the first and second transconductance modules, the voltage at the terminals of said resistor constituting the output signal of the analog adder.
In a particular embodiment of the invention, each transconductance module is constituted by a pair of transistors whose emitters are connected to a current source via resistors, whose bases constitute a symmetrical input of the transconductance module, the collector of one of the transistors constituting the output of the transconductance module.
In the majority of applications for which such a reading system is intended, the bases of the transistors which constitute the first and the second amplifiers must be subjected to a DC bias voltage. This voltage must be independent of the variations of the AC voltages to which said bases are subjected.
A preferred embodiment of the invention thus provides a system for reading magnetic information as described above, which is characterized in that each amplifier comprises an element having an inductive behavior and connected between the bases of the transistors in the amplifier, said inductive element comprising:
a pair of transistors, referred to as primary pair, whose emitters are connected to a current source, whose bases are connected to the collectors of the transistors of the amplifier, and whose collectors are interconnected via a capacitor, and
another pair of transistors whose emitters are connected to a current source, whose bases are connected to the collectors of the transistors of the primary pair, and whose collectors are connected to the bases of the transistors of the amplifier.
The inductive behavior of the elements arranged between the bases of the transistors of each amplifier allows a fixed bias voltage to be attributed to said bases, which voltage is independent of variations of the AC voltage to which the bases are subjected.
These and other aspects of the invention are apparent from and will be elucidated with reference to the embodiments described hereinafter.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing a system for reading magnetic information according to the invention,
FIGS. 2a and 2b are, respectively, a partial electric circuit diagram of an amplifier provided with decoupling capacitors, and an AC-equivalent circuit diagram of said amplifier,
FIGS. 3a and 3b are, respectively, an AC-equivalent circuit diagram, equivalent to the previous circuit diagram, and a partial electric circuit diagram of a corresponding circuit,
FIG. 4 is an electric circuit diagram illustrating an analog adder included in a particular embodiment of the invention, and
FIG. 5 is an electric circuit diagram illustrating an element having an inductive behavior, included in a preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows partially a system for reading magnetic information according to the invention, which system comprises:
a read head provided with a magnetoresistive bar MR whose electric resistivity varies when it is subjected to a variation of the magnetic field, said bar having a first terminal A and a second terminal B and being intended to be traversed by a bias current IO of a predetermined value,
a first amplifier comprising a first transistor T1 and a second transistor T2 arranged as a differential pair, whose bases are connected to the first and second terminals A and B of the magnetoresistive bar MR and whose collectors constitute a symmetrical output of the first amplifier, supplying a voltage V01.
This reading system also comprises:
a second amplifier comprising a third transistor T3 and a fourth transistor T4 arranged as a differential pair, whose bases are connected to the first and second terminals A and B of the magnetoresistive bar MR and whose collectors constitute a symmetrical output of the second amplifier, supplying a voltage V02,
a first and a second capacitor having nominal values which are equal to C, the first capacitor being inserted between the base of the first transistor T1 and the first terminal A of the magnetoresistive bar MR, the second capacitor being inserted between the base of the fourth transistor T4 and the second terminal of the magnetoresistive bar MR, and
an analog adder ADD having a first symmetrical input connected to the symmetrical output of the first amplifier, a second symmetrical input connected to the symmetrical output of the second amplifier, and an output intended to supply a signal Vout which is representative of the sum of the values of the signals V01 and V02 received at the first and second inputs.
The bases of the transistors which constitute the first and second amplifiers, T1, T2 and T3, T4 are interconnected by means of elements having an inductive behavior, L1 and L2, respectively. This ensures that the bases of these transistors are subjected to a bias voltage which is independent of the variations of the alternating voltages to which these bases are subjected.
FIGS. 2a and 2b are,respectively, a partial electric circuit diagram of an amplifier provided with decoupling capacitors, and an equivalent circuit diagram, for small AC signals, of said amplifier. These diagrams will help to demonstrate the advantages of the structure shown in FIG. 1.
FIG. 2a shows an amplifier comprising a first transistor T1 and a second transistor T2 arranged as a differential pair, whose bases are connected to terminals A and B, respectively, via decoupling capacitors having a value C0. FIG. 2b is an equivalent circuit diagram, for small AC signals, of the amplifier described above, viewed from its two input terminals A and B. In a first approximation, this circuit is composed of two capacitors having a value C0 which are equivalent to a single capacitor having a value CO/2, in series with a resistor R which represents the equivalent input resistance of the differential pair T1, T2.
FIG. 3a is a diagram, for small AC signals, showing a circuit whose impedance, viewed from the input terminals A and B, is equivalent to that of the circuit shown in FIG. 2b. The circuit shown in FIG. 3a comprises two branches which are arranged in parallel between the terminals A and B, each composed of a capacitor and a resistor arranged in series. For the sake of equivalence with the previous diagram, the value of the capacitors must be CO/4 and that of the resistors must be 2R. FIG. 3b is an electric circuit diagram of a circuit whose impedance, viewed from its input terminals A and B, may be described by means of the previous diagram. This circuit comprises two branches arranged in parallel between the terminals A and B, each composed of a capacitor having a value CO/4 arranged in series with an amplifier. The amplifiers are similar to the one described above. The first amplifier is thus constituted by a first transistor T1 and a second transistor T2, arranged as a differential pair, while the second amplifier is constituted by a third transistor T3 and a fourth transistor T4, arranged as a differential pair. As each amplifier must have an equivalent input resistance of 2R, they are connected to a current source I/2 supplying a current which is twice as small as in the case of the amplifier shown in FIG. 2a. The capacitors of the value CO/4 ensure the decoupling of the DC component of the voltage between the terminals A and B. This structure is the one used in the reading system according to the invention, shown in FIG. 1. If the decoupling capacitors of the value C0 allow to obtain a low cut-off frequency FO of the order of megahertz values, for example, the same low cut-off frequency FO is obtained in the reading system according to the invention by means of decoupling capacitors having a value which is four times smaller. If CO is of the order of about a hundred picofarads, and thus difficult to realize in an integrated form, the first and second capacitors C shown in FIG. 1 should thus have a value of the order of several tens of picofarads, which may then be integrated.
FIG. 4 is an electric circuit diagram partially showing an analog adder ADD included in a particular embodiment of the invention. This adder comprises a first and a second transconductance module, each module being constituted by a pair of transistors T5, T6 and T7, T8 whose emitters are connected to a current source IT via resistors RT. The bases of the transistors constituting each of the transconductance modules, T5, T6 and T7, T8 constitute symmetrical inputs of the transconductance modules, receiving V01 and V02, respectively. The collectors of transistors T5, T6 and T7, T8 constitute symmetrical current outputs of the transconductance modules. The collector of the fifth transistor T5 supplies a current I1 which may be expressed as K.(1+x).V01 in which X is a multiplicative constant, and the value of x varies between 0 and 1 as a function of the voltage V01. The collector of the sixth transistor T6 supplies a current I'1 which may be expressed as K.(1-x).V01. The collector of the seventh transistor T7 supplies a current 12 which may be expressed as K.(1+x).V02, and the collector of the eighth transistor T8 supplies a current I'2 which may be expressed as K.(1-x).V02. The adder ADD also comprises a first and a second resistor RL each having a terminal connected to a fixed voltage terminal, here the circuit's ground. The first resistor RL is also connected to the collectors of the fifth and seventh transistors T5 and T7, while the second resistor RL is connected to the collectors of the sixth and eighth transistors T6 and T8, respectively. The first resistor RL is thus traversed by a current I3 which is equal to the sum of the currents I1 and I2, while the second resistor RL is traversed by a current 1'3 which is equal to the sum of the currents I'1 and I'2. The difference between the voltages at the terminals of the first and second resistors RL constitutes the output signal Vout of the adder ADD. This may be expressed as Vout=K'.(V01+V02), which indeed readily constitutes the output equation which was searched for.
FIG. 5 is an electric circuit diagram showing an element having an inductive behavior L1 included in a preferred embodiment of the invention. This inductive element L1 comprises:
a pair of transistors T9, T10, referred to as primary pair, whose emitters are connected to a current source IS, whose bases are connected to the collectors of the transistors T1 and T2 of the first amplifier, and whose collectors are interconnected via a capacitor C1, and
another pair of transistors T11, T12, whose emitters are connected to a current source IS, whose bases are connected to the collectors of the transistors of the primary pair T9, T10 and whose collectors are connected to the bases of the transistors T1 and T2.
If the transconductances of the transistors T1, T9 and T11 are defined as being equal to gm1, gm2 and gm3, respectively, the voltage VC12 is expressed as -gm1RC.(VA-VB), while VB12 is expressed as -gm2.VC12/(j.2.C.ω), the current I11 being expressed as gm3.VB12/2. These three equations directly lead to the equation (VA-VB)/I11=j.ω.4.C/(gm1.gm2.gm3.RC), which defines the impedance of the element L1. This impedance can be expressed as j.ω.Leq, which corresponds to an inductive behavior. | The invention relates to a system for reading magnetic information, comprising a magnetoresistive bar and a first differential amplifier connected to the magnetoresistive bar. A reading system according to the invention also comprises a second differential amplifier arranged in parallel with the first amplifier, a first capacitor arranged between the first transistor and the magnetoresistive bar, and a second capacitor arranged between the fourth transistor and the bar, and an analog adder combining the output signals of the first and second amplifiers. This structure allows integration of the decoupling capacitors and thus prevents the occurrence of external resistances and inductances which are detrimental to the common-mode reject rate. | 6 |
MANAGEMENT OF AN OBJECT
[0001] This application is a continuation application claiming priority to Ser. No. 13/226,599, filed Sep. 7, 2011.
FIELD OF THE INVENTION
[0002] The present invention relates to a method and apparatus for managing an object, and particularly to a method and apparatus for checkout management of an object located in a place such as a warehouse or a shop.
BACKGROUND OF THE INVENTION
[0003] A conventional method for checkout management of commodities located in a facility such as a warehouse or a shop involves attaching a tag to each commodity, emitting a weak radio wave toward the tag from an antenna near a gate of the facility to detect a commodity passing through the gate, and restricting exit from the facility as necessary.
SUMMARY OF THE INVENTION
[0004] The present invention provides a method and associated system and computer program product for managing an item in a place, which comprises:
[0005] detecting, by a processor of a computer system, that: (i) the item in the place is being moved, (ii) an operating object inside the place is moving, and (iii) the operating object inside the place and the item in the place are within a previously specified distance of each other;
[0006] responsive to said detecting, said processor determining whether the operating object has a reservation for borrowing the item and subsequently determining that the operating object does not have said reservation for borrowing the item;
[0007] responsive to said determining that the operating object does not have said reservation for borrowing the item, said processor determining that the operating object has illegitimately taken the item; and
[0008] responsive to said determining that the operating object has illegitimately taken the item, said processor preventing the operating object from removing the item from the place.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a conceptual block diagram of an object management system and an environment in which the system is applied, in accordance with embodiments of the present invention.
[0010] FIG. 2 is a diagram of a hardware configuration for implementing an object management apparatus of the present invention, in accordance with embodiments of the present invention.
[0011] FIG. 3 is a conceptual diagram of a system configuration of the object management apparatus, in accordance with embodiments of the present invention;
[0012] FIG. 4 is a data structure of an object management database 1024 , in accordance with embodiments of the present invention.
[0013] FIG. 5 is an operational flow in the object management system, in accordance with embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] In the method of the present invention, a first positional information communication unit is associated with a first object (e.g., an item), and a second positional information communication unit is associated with a second object (e.g., a managing object) that potentially operates the first object.
[0015] A location management unit receives positional information about the first object from the first positional information communication unit, and the location management unit receives positional information about the second object from the second positional information communication unit.
[0016] The location management unit requests an object management unit to check an access right to the first object if a movement of the first object is detected, if a movement of the second object is detected, and if a location of the first object and a location of the second object are within a predetermined range.
[0017] The object management unit refers to access right information about the first object to determine whether or not the second object is authorized to move the first object.
[0018] In the above management method, the object management unit may display an alarm message on display means if the second object is not authorized to move the first object.
[0019] Alternatively or additionally, in the above management method, the object management unit may cause a block unit to restrict a movement of the second object if the second object is not authorized to move the first object.
A. Description of Terms
[0020] Terms used throughout the specification and the claims will be described next.
[0021] (1) Unit: Units include all devices connectable to a network or a bus.
[0022] For example, units include server computers, portable computers, displays, storage devices, office machines such as facsimiles and copiers, printers, and firmware.
[0023] Units may also be virtual units implemented by computer software.
[0024] Besides the above typical examples, a unit may necessarily be confined in a single housing but functions of such a unit as above may be physically distributed as long as the distributed functions serve as the unit.
[0025] Further, a unit may refer to a program code or a group of program codes residing in computer memory.
[0026] (2) Object: Objects include all tangibles, such as commodities, parts, intermediate products, machines, books, documents, natural products, and living things. Objects also include matters that typically assume no particular shapes, such as gases and liquids manageably contained in containers or the like.
[0027] In this specification, objects (i.e., operating objects) also include persons, conveyer machines, and robots capable of operating objects (e.g., items). Operating objects typically encompasses the act of carrying the objects or items, including borrowing and using the objects or items.
[0028] (3) Positional Information: Positional information includes any information capable of uniquely specifying the location of an object.
[0029] The positional information is typically represented in the form of, although not limited to, XYZ coordinates or polar coordinates.
[0030] The accuracy of the positional information can be selected as appropriate for the use of the present invention.
[0031] (4) Access Right: An access right refers to authority to operate an object, for example authority to carry an object.
B. Hardware Configuration
[0032] FIG. 1 is a conceptual block diagram of an object management apparatus and an environment in which the apparatus can be applied, it accordance with embodiments of the present invention.
[0033] In an embodiment, an object management apparatus 102 manages items such as 130 , 131 , and 132 placed on storage shelves 120 , 121 , and 122 in a warehouse 160 , and a visitor 150 (e.g., a person). The warehouse 160 may be more generally a place such as a warehouse or a shop.
[0034] The objects (e.g., items) such as 130 , 131 , and 132 have RFID (Radio Frequency Identification) tags 140 141 , and 142 associated therewith, respectively.
[0035] More specifically, the tags are attached to, embedded in, or tied with (e.g., a wire), the objects, so that the tags are moved with the movement of the objects.
[0036] Positional information about the tags is obtained with a receiver 103 . The obtained positional information is sent to the object management apparatus 102 .
[0037] As a technique of obtaining the positional information about the individual tags with the receiver 103 , a Mojix STAR System of Mojix Inc. can be used. The Mojix STAR system realizes an increase in the receiver sensitivity by 100,000 times compared with conventional UHF-band REID readers, and a reading distance exceeding about 200 meters. The Mojix STAR system is also “capable of high-accuracy location detection with UHF-band passive tags (a location accuracy of about 1 to 3 m).”
[0038] Displays 110 , 111 , and 112 may be attached to the display shelves or may be placed at convenient locations in the warehouse 160 .
[0039] The visitor 150 enters the warehouse 160 , carrying an RFID tag 165 .
[0040] The displays 110 , 111 , and 112 may display guidance for the visitor 150 by communicating with the object management apparatus 102 via the receive 103 .
[0041] A block unit 170 is provided at agate of the warehouse 160 .
[0042] The block unit 170 may be a bar for restricting entrance and exit or an automatic door, for example.
[0043] A gate management unit 104 cooperates with the object management apparatus 102 to control the operation of the block unit 170 .
[0044] A user computer 101 , including an input device and a display device (not shown), inputs data to the object management apparatus 102 through the input device and displays data received from the object management apparatus 102 on the display device.
[0045] The user computer 101 , the object management apparatus 102 , the gate management unit 104 , and the receiver 103 are interconnected via a communication network 150 such as a local area network.
[0046] FIG. 2 is a diagram of a hardware configuration for implementing the object management apparatus 102 , in accordance with embodiments of the present invention. A computer system of the present invention comprises the hardware configuration depicted in FIG. 2 of the object management apparatus 102 .
[0047] The other units in FIG. 1 (i.e., the user computer 101 , the gate management unit 104 , and the receiver 103 ) may also be implemented in a similar hardware configuration within a computer system.
[0048] Components to be described below are illustrative, and not all of them are required components for the present invention.
[0049] Each unit may have some of its components removed or added as appropriate for functions of the unit.
[0050] The unit includes a CPU 202 , a memory 204 , a storage device 206 , an I/O control device 210 , a user interface 214 , a bus 208 interconnecting these components, and a communication port 212 .
[0051] Code of a computer program running on the unit may be stored in the storage device 206 or may be introduced into the memory 204 from an external apparatus via the communication port 212 and the I/O control device 210 .
[0052] The computer program code may be executed by the CPU 202 after being loaded into the memory 204 , or may be executed by the CPU 202 while remaining stored in the storage device 206 . A computer program product comprises a computer readable storage device (e.g., the storage device 206 ) such that the program code is stored on the storage device, wherein the program code is configured to be executed by a processor (e.g., the CPU 202 ) to perform the methods of the present invention.
[0053] In any case, the memory 204 may also be used as temporary storage memory in one embodiment.
[0054] The user interface 214 is used for displaying the operation state of the unit, inputting the operation mode, and the like.
[0055] The computer program code may be divided into pieces and recorded separately on a plurality of storage media. Part of the divided pieces of code may be recorded on a storage medium in another external information processing apparatus connected to the unit via the communication port 212 and the succeeding communication network 150 , and the CPU 202 may cooperatively execute the divided pieces of code. Distributing the divided pieces of code to a plurality of apparatuses and cooperatively executing the pieces of code is embodied as a client-server system for example. Which pieces of code are executed by each apparatus to implement its functions is a matter of choice as appropriate in system design, and the present invention encompasses any form of such choice.
[0056] The unit ay also be configured as follows. The unit is physically separated on the basis of functional blocks to be described below. The hardware as shown in FIG. 2 is provided for each functional block, and the functional blocks cooperate via the respective communication ports 212 .
[0057] An operating system running in the unit may be, although is not necessarily, an operating system that supports a graphic user interface multi-window environment as standard, such as Windows XP (R), AIX (R), or Linux (R), or any other operating system.
[0058] The present invention is not limited to any particular operating system environment.
[0059] A computer system rises a processor (e.g., the CPU 202 ), a memory (e.g., the memory 204 ) coupled to the processor, and a computer readable storage device coupled to the processor, said storage device containing program code configured to be executed by the processor via the memory to implement the methods of the present invention.
C. System Configuration
[0060] FIG. 3 is a conceptual diagram of a system configuration of the object management apparatus, in accordance with embodiments of the present invention.
[0061] The object management apparatus 102 includes an object management control unit 1022 , an object management database 1024 , a location management unit 1026 , and an I/O unit 1028 .
<Object Management Control Unit>
[0062] The object management control unit 1022 sends a command for obtaining current positional information about an individual object (e.g., an item) to the receiver 103 via the I/O unit 1028 .
[0063] The object about which the positional information should be obtained is identified by referring to the object management database 1024 .
[0064] The object management control unit 1022 obtains the current positional information about the individual object from the receiver 103 via the I/O unit 1028 and updates the content of the object management database 1024 .
[0065] Also, in response to a notification of the entrance of the visitor 150 by the gate management unit 104 , the object management control unit 1022 sends a command for obtaining positional information about the visitor 150 to the receiver 103 and updates the positional information about the visitor 150 in the object management database 1024 .
[0066] The object management control unit 1022 may send the commands for obtaining the positional information to the receiver 103 at regular intervals.
[0067] Alternatively or additionally, once the visitor 150 is recognized by the object management control unit 1022 , the object management control unit 1022 may obtain the positional information at regular intervals only about the visitor 150 and about an object that the visitor 150 is authorized to access.
[0068] The object management control unit 1022 obtains, from the receiver 103 , the positional information about the RFID tags such as 140 , 141 , and 142 attached to the objects such as 130 , 131 , and 132 in the warehouse 160 , and about the RFID tag 165 carried by the visitor 150 , and stores the positional information in the object management database 1024 .
[0069] The location management unit 1026 refers to the object management database 1024 to monitor, at regular intervals, the positional information about the visitor 150 (who borrows an object) and the positional information about the object that the visitor intends to borrow.
[0070] The location management unit 1026 also monitors changes in the positional information about the object over time to determine the moving speed (i.e., velocity) of the object.
[0071] As will be described below, if the positions and the moving speeds of the visitor 150 and the object meet certain relationships, the object management control unit 1022 is notified of this fact.
[0072] FIG. 4 is a data structure 400 (in the form of a table) of the object management database, in accordance with embodiments of the present invention.
[0073] The structure shown in FIG. 4 is merely an example, and the data arrangement order and data types are not limited to the example shown. In short, it is only necessary that the positional information about the objects (e.g., items) 130 , 131 , and 132 , the positional information about the visitor 150 , and the access right of the visitor 150 to an object are reflected.
[0074] The data structure 400 is a reservation table that includes an identifier 402 of an object, whether or not a reservation for lending of the object has been made 404 , the date of starting the lending 406 of the object, the date of finishing the lending 408 of the object, an identifier 410 of borrower who is an operating object who borrows the object (e.g., an operating object such as the visitor 150 authorized to enter the room and take out the object), current positional information 412 about the borrower (e.g., visitor 150 ), and current positional information 414 about the object.
[0075] For example, an object AD-6136 is reserved for lending, and the date of starting the lending is Jan. 4, 2010, and the date of finishing the lending is Jan. 5, 2010.
[0076] The borrower is AA6400.
[0077] This borrower AA6400 is permitted to enter the warehouse 160 in a period between these dates of Jan. 4, 2010 and Jan. 5, 2010.
[0078] The entrance is permitted or denied by the object management control unit 1022 through referring to the object management database 1024 and controlling the gate management unit 104 .
[0079] The current location of the visitor is (100, 50), and the current location of the object is (99, 51).
[0080] An object BO-7799 has an expected borrower AA8000, who has not entered the warehouse 160 . The object is stored at a location (200, 100).
[0081] The I/O unit 1028 connects the object management control unit 1022 to the gate management unit 104 , the receiver 103 , and the displays 110 , 111 , and 112 via the external network 150 .
[0082] FIG. 5 shows an operational flow in an object management system, in accordance with embodiments of the present invention.
[0083] When the visitor 150 (i.e., an operating object) reaches near the block unit 170 , the gate management unit 104 notifies the object management apparatus 102 of this fact.
[0084] The object management control unit 1022 in the object management apparatus 102 sends, to the receiver 103 , a command for obtaining the identifier of the visitor 150 from the RFID tag carried by the visitor 150 . The obtained identifier is sent to the object management control unit 1022 (step 502 ).
[0085] The object management control unit 1022 refers to the object management database 1024 . If the visitor 150 has a reservation for borrowing an object (e.g., an item) (step 504 ), the object management control unit 1022 controls the gate management unit 104 to open the block unit 170 which enables the visitor 150 to enter the warehouse 160 (step 506 ).
[0086] As described above, the object management control unit 1022 monitors the current location of the visitor 150 thereafter.
[0087] According to the location of the visitor 150 in the warehouse 160 , the object management control unit 1022 may send guide information to the displays 110 , 111 , and 112 via the receiver 103 for guiding the visitor 150 to the reserved object(step 508 ).
[0088] As described above, the location management unit 1026 in the object management apparatus 102 monitors the positions of the visitor 150 and the reserved object at regular intervals, and also monitors changes in the positional information about the object over time to determine the moving speed (i.e., velocity) of the object.
[0089] If a fact is established that: (i) the visitor 150 in the warehouse 160 and the reserved object are within a predetermined (i.e. previously specified) distance of each other (step 510 ), (ii) the object is being moved (i.e., a movement of the object is detected in step 512 ), and (iii) the visit r is moving (i.e., a movement of the visitor is detected in step 514 ), then the location management unit 1026 notifies the object management control unit 1022 of this fact.
[0090] The object management control unit 1022 refers to the object management database 1024 to determine whether or not the visitor has a reservation for borrowing the object being moved (step 516 ).
[0091] If in step 518 the visitor does not have a reservation for the borrowing of the object, the object management control unit 1022 determines that the object has been illegitimately taken by the visitor 150 .
[0092] In step 520 , the object management control unit 1022 causes the user computer 101 to display an alarm message on a display device and transmit reports to a system manager.
[0093] The object management control unit 1022 may also control the gate management unit 104 to close the block unit 170 (step 524 ) when the visitor 150 is detected reaching near the gate through the receiver 103 (step 522 ), which prevents the visitor 150 from removing the object from the warehouse 160 .
[0094] While particular embodiments of the present invention have been described herein for purposes of illustration, many modifications and changes will become apparent to those skilled in the art. Accordingly, the appended claims are intended to encompass all such modifications and changes as fall within the true spirit and scope of this invention. | A method and associated system for managing an item in a place. Positional information about an operating object and positional information about the item is monitored at regular intervals by a receiver receiving locational coordinates of a tag associated with the item and a tag carried by the operating object. Based on the positional information, it is detected i) that the item in the place is being moved, (ii) that the operating object inside the place is moving, (iii) a distance between the location of the operating object and the item, and (iv) that the operating object inside the place and the item in the place are within a previously specified distance of each other. After the previous detections, it is determined that the operating object has illegitimately taken the item, which triggers preventing the operating object from removing the item from the place. | 6 |
BACKGROUND OF THE DISCLOSURE
Most machines for washing articles, such as dishes or laundry, require a detergent as the cleaning agent. This detergent is available in several forms including liquid, gel, powder, and tablet. Regardless of the form of the detergent, the active cleaning agent within the detergent may be chlorine-based or enzyme-based. The current approach washes the articles the same way, regardless of whether the detergent used is a solid-type or liquid-type, or whether it is chlorine-based or enzyme-based. This approach may not maximize the effectiveness of the detergent used, which may result in sub-standard washing. Thus, there is a continuing need for a machine that exploits the efficiency of the detergent used during the wash-cycle.
SUMMARY OF THE DISCLOSURE
The present disclosure provides a detergent module apparatus and control techniques that may be employed to determine if the detergent stored in the module is a solid-type or liquid-type detergent. This determination may then be used by a machine controller to select a wash algorithm based at least in part upon the type of detergent stored in the detergent module to facilitate effective utilization of the cleaning efficiency of the detergent.
A detergent module for dispensing detergent during a wash-cycle is disclosed, which includes a compartment with an opening to dispense the detergent and to allow the compartment to be thoroughly rinsed at some point during the wash-cycle. The detergent module also includes a sensor which provides a signal that indicates whether the detergent in the compartment is a solid-type or liquid-type detergent.
In some embodiments, the detergent module is situated in a dishwashing machine, and in other embodiments the detergent module is situated in a washing machine for laundry. Regardless of the type of machine, the detergent module may include a cover that opens at a point during the wash-cycle to dispense the detergent and allows the compartment to be rinsed. In other embodiments, water may be mixed with the detergent to create a washing solution while it is in the compartment and the pressure from the water source forces the washing solution from the detergent module. In some embodiments, the module includes multiple compartments which can individually store and dispense detergent during the wash-cycle.
A dishwasher is provided, which includes a housing, connections for water supply and removal, a heating element, a detergent module to store and dispense detergent during a wash-cycle, and a machine controller which selects a wash algorithm based at least in part upon the type of detergent stored in the detergent module. In some embodiments, the type of detergent is received from a user-input, where the user manually enters the type and subtype of detergent in the detergent module. In other embodiments, the dishwasher includes a sensor which determines whether the detergent is a solid-type or liquid-type detergent and provides that signal to the machine controller.
A clothes washer is provided, which includes a housing, connections for water supply and removal, a detergent module to store and dispense detergent during a wash-cycle, and a machine controller which selects a wash algorithm based at least in part upon the type of detergent stored in the detergent module. In some embodiments, the type of detergent is received from a user-input, where the user manually enters the type and subtype of detergent in the detergent module. In other embodiments, the dishwasher includes a sensor which determines whether the detergent is a solid-type or liquid-type detergent and provides that signal to the machine controller.
A method for washing articles is provided, which includes providing detergent to a detergent module in a machine, receiving a detergent-type signal which indicates whether the detergent in the detergent module is a solid-type detergent or a liquid-type detergent, selecting one of a plurality of different wash algorithms based at least in part on the detergent-type signal or value, and controlling the machine to perform a wash-cycle based on the selected wash algorithm. In some embodiments, the type of detergent is received from a user-input, where the user manually enters the type and subtype of detergent in the detergent module. In other embodiments, the dishwasher includes a sensor which determines whether the detergent is a solid-type or liquid-type detergent and provides that signal to the machine controller.
BRIEF DESCRIPTION OF THE DRAWINGS
One or more exemplary embodiments are set forth in the following detailed description and the drawings, in which:
FIG. 1 is a schematic diagram illustrating an exemplary machine for washing articles including a detergent module for storing and dispensing detergent and a machine controller having multiple algorithms selected at least partially based upon the type of detergent stored in each of the one or more compartments of the detergent module;
FIG. 2 is a perspective view of an exemplary detergent module with multiple compartments wherein individual covers close over corresponding individual compartments in the machine of FIG. 1 ;
FIG. 3 is a front-elevational view of an exemplary dishwasher machine embodiment including the exemplary detergent module of FIG. 1 ; and
FIG. 4 is a schematic drawing of an exemplary laundry washing machine embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
For purposes of this disclosure, a “solid-type” detergent is a detergent in a dry, solid form such as, but not limited to, powder or tablet. A “liquid-type” detergent is a detergent in viscous form such as, but not limited to, liquid or gel. A “detergent-type” denotes whether the detergent is a solid-type or liquid-type detergent and may also include the “detergent-subtype” information. A “detergent-subtype” denotes whether the detergent is chlorine-based or enzyme-based. Finally, the term “wash-cycle” includes every stage of operation of a machine used for washing articles, including but not limited to, a pre-cleaning stage, a cleaning stage, a pre-rinse stage, a rinse stage, and a post-rinse stage.
Referring now to the drawings, where like reference numerals are used to refer to like elements throughout, and wherein the various features are not necessarily drawn to scale, the present disclosure relates to machines for washing articles and more particularly to those machines with multiple wash algorithms based at least in part upon the type of detergent used for the wash and will be described with particular reference thereto, although the exemplary apparatus and methods described herein can also be used in other dispensing algorithms based on other types of contents of a module, such as but not limited to bleach, rinse agent (e.g. Cascade Crystal Clear®, Jet-Dry®, white vinegar, etc.), and fabric softener and are not limited to the aforementioned application.
FIG. 1 illustrates an exemplary machine 100 for washing articles including a detergent module 105 and a machine controller 140 . The exemplary detergent module 105 includes multiple compartments 114 ( FIG. 2 ) wherein the compartments 114 individually include sensors 120 operative to determine whether the type of detergent stored within the associated compartment 114 is a solid-type or liquid-type detergent. The sensors 120 provide N detergent-type signals 122 to the machine controller 140 , where N is a positive integer. The machine controller 140 will select from X wash algorithms 142 based, at least in part on the values of the detergent-type signals 122 . The selected algorithm 142 will determine, inter alia, the timing and various temperatures of the wash-cycle. In some embodiments, the machine controller 140 is a microprocessor, while in other embodiments, the machine controller 140 is comprised of discrete circuitry. The controller 140 may be implemented as any suitable form of hardware, software, firmware, programmable logic, or combinations thereof, and may be a unitary control component or may be implemented in distributed fashion.
FIG. 2 illustrates one suitable embodiment of a detergent module 105 including two compartments 114 with corresponding covers 116 and at least one sensor 120 to be used in a machine 100 for washing articles. The detergent is provided to the compartment 114 by a user or a bulk dispenser (not shown), and the cover 116 seals the compartment 114 to protect the detergent until the desired time in the wash-cycle determined by the selected wash algorithm 142 . At the desired time, the cover 116 is opened by the machine controller 140 , and the detergent stored in the compartment 114 is dispensed to the wash. The covers 116 shown in the example of FIG. 2 are opened along a horizontal hinge to allow detergent to be dispensed downward via gravity, but other embodiments allow the cover 116 to be, inter alia, opened along a vertical hinge, slid open via a sliding mechanism, or rotated open on an offset pivot hinge. In certain embodiments, water or the washing solution (water-detergent mixture) enters the compartment where it mixes with the detergent, and is dispensed to the wash tub of the machine through an opening. Other non-gravitational means can be provided to dispense the detergent.
FIG. 2 further illustrates a sensor 120 located in one of the compartments 114 of the detergent module 105 . In the embodiment of FIG. 2 , the sensor 120 is located at or near the bottom portion 115 of the compartment 114 such that as the module 105 is mounted upright (e.g., when the washer door is closed in a dishwasher implementation), gravity forces detergent toward the sensor 120 . Two points of a conductivity sensor 120 are placed horizontally in spaced relationship to one another at the back of the compartment 114 in the example of FIG. 3 . When a liquid-type detergent is added to the compartment 114 and the detergent module 105 is in position for a wash-cycle (e.g., upright in this embodiment), the conductivity of the detergent, due to the electrolytes in the detergent provides a relatively low resistance electrical connection between the two conductivity points of the sensor 120 , which produces a signal 122 indicating the presence of a liquid-type detergent. A solid-type detergent presents a relatively high resistance electrical connection between the two conductivity points of the sensor 120 , which produces a signal 122 indicating the absence of a liquid-type detergent. Other embodiments use other types of sensors such as, but not limited to, capacitive sensors or strips, ultrasonic sensors, and microwave sensors, or combinations thereof. The number of sensors 120 in the detergent module 105 may range from zero to the number of compartments 114 or more. In certain embodiments, a detergent-type signal 122 can be provided to the machine controller 140 by the user through a user-input. In such an embodiment, no sensor 120 is needed to determine the detergent-type. Other embodiments may provide for user-generated detergent-type signal(s) 122 in combination with sensor-generated detergent-type signal(s) 122 . In certain embodiments, the user may also specify the detergent-subtype to the machine controller 120 through a user-input, and the machine controller selects a washing algorithm 142 based at least in part on the detergent-subtype.
A film of residual detergent left in the compartment 114 after a wash-cycle may produce a false presence of liquid-type detergent, so the compartments 114 of the exemplary module 105 include openings (via covers 116 ) to allow the compartment to be rinsed so there is limited or no residual detergent in the compartment 114 . The sensor points 120 are placed in such a way that any leftover washing solution or water will not register a false positive on back-to-back washes. In one embodiment, the conductivity points are positioned sufficiently near the bottom of the compartment 114 when the detergent module 105 is in position for the wash-cycle to allow for sensing the typical minimum amount of detergent, but spaced sufficiently from the lowest point of the compartment in the wash cycle position to not respond to leftover washing solution or water in the compartment.
FIG. 3 illustrates an exemplary dishwasher 200 including the exemplary multi-compartment detergent module 105 of FIG. 2 mounted on the door 220 . The dishwasher 200 further includes a housing 210 and a wash tub 212 . In one embodiment, the machine controller 140 is located in the detergent module 105 , or the controller 140 may be separately located with suitable interconnections to provide the detergent-type signal 122 and other appropriate signaling between the controller 140 and the module 105 . The dishwasher 200 functions as the machine 100 described above.
FIG. 4 illustrates an exemplary laundry washing machine 300 including a detergent module 105 , machine controller 140 , an agitator 310 , and hot and cold water supplies 312 , 314 . Other washing machine embodiments are possible that do not include an agitator. Either user-input or the sensor 120 ( FIG. 1 ) provides a detergent-type signal to the machine controller 140 , which will select a wash algorithm 142 ( FIG. 1 ) based at least in part on the detergent-type. The machine controller 140 will then control the valves 322 , 324 , 326 and agitator 310 during the wash-cycle according to the selected wash algorithm 142 . When the machine controller 140 determines that detergent should be added to the tub, it activates valve 326 to cause water to flow through an opening 328 of the module 105 so as to mix the water with the detergent and dispense the solution to the tub through tube 330 . During this process, at least the region of the compartment 114 ( FIG. 2 ) proximate sensor 120 is sufficiently rinsed of any residual washing solution to avoid a false sensor response.
The above examples are merely illustrative of several possible embodiments of various aspects of the present disclosure, wherein equivalent alterations and/or modifications will occur to others skilled in the art upon reading and understanding this specification and the annexed drawings. In particular regard to the various functions performed by the above described components (assemblies, devices, systems, circuits, and the like), the terms (including a reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component, such as hardware, software, or combinations thereof, 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 illustrated implementations of the disclosure. In addition, although a particular feature of the disclosure may have been illustrated and/or described with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Furthermore, references to singular components or items are intended, unless otherwise specified, to encompass two or more such components or items. Also, to the extent that the terms “including”, “includes”, “having”, “has”, “with”, or variants thereof are used in the detailed description and/or in the claims, such terms are intended to be inclusive in a manner similar to the term “comprising”. The invention has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations. | A detergent module for dispensing detergent during a wash-cycle is presented in which a sensor senses and indicates or a user via control input indicates whether the detergent in the module is a solid-type detergent or a liquid-type detergent, and the detergent-type indication is used by a dishwashing machine or a laundry washing machine to select a washing algorithm tailored to exploit the cleaning efficiency of the detergent. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
This patent is a divisional of U.S. patent application Ser. No. 11/903,208 filed Sep. 19, 2007, which is a continuation-in-part patent application that claims priority and incorporates herein by reference U.S. patent application Ser. No. 11/056,848, now issued as U.S. Pat. No. 7,229,330; U.S. patent application Ser. No. 11/811,616, filed Jun. 11, 2007, now issued as U.S. Pat. No. 7,494,393; U.S. patent application Ser. No. 11/811,605 filed Jun. 11, 2007, now issued as U.S. Pat. No. 7,491,104; U.S. patent application Ser. No. 11/811,606, filed Jun. 11, 2007, now issued as U.S. Pat. No. 7,485,021; U.S. patent application Ser. No. 11/811,604, filed Jun. 11, 2007, now issued as U.S. Pat. No. 7,465,203; and U.S. patent application Ser. No. 11/811,617, filed Jun. 11, 2007, now issued as U.S. Pat. No. 7,494,394.
FIELD OF THE INVENTION
The present invention pertains to the field of water sports and boating and more specifically to electronic devices for use in water sports.
BACKGROUND OF THE INVENTION
Competitors in trick, jump, and slalom ski and wakeboard events require tow boats capable of consistent and accurate speed control. Successful completion of slalom and jump runs require passes through a competition water course at a precise specific speed. Competition rules usually require that said speed requirements be confirmed by use of a speed measurement system. For example, American Water Ski Association Three-Event Slalom and Jump competitions specify a required time window for completion of all segments of the course to confirm that speed was maintained adequately throughout the pass. These times have historically been measured either using manual stopwatch measurements or, more recently, using magnetic sensors which are triggered by the presence of magnets attached to buoys in the water in close proximity to the path of the tow boat at the required timing measurement points in the course. Course times have to be reported and logged for every individual pass in competition. Reliability of triggering the magnetic sensor, as well as maintenance of the magnets attached to the buoys has consistently caused major difficulties in running competitive 3-event competitions.
SUMMARY OF THE INVENTION
The present invention provides a consistent, maintenance free and accurate method of measuring time of passage of a tow boat and skier through courses such as those used for slalom and jump competitions without the need for magnets or other physical attachments to the course infrastructure. Global Positioning System (GPS) satellite technology is used to map and memorize the location of courses in a permanent memory within a computer system. The system is then able to recognize every time the tow boat passes through the course using continuously updated GPS position estimates. By interpolating between periodic position updates, the system can accurately estimate time of closest approach to the entry gate to the course, and subsequently track time to all points of interest down the course using either the same GPS position measurement technique, or by tracking displacement of the tow boat down the line of the course using other techniques such as integration of velocity to derive position displacement.
An automatic timing measurement system that provides a measure of time of passage of a watercraft through a prescribed course. Algorithms based on inertial or other estimates augmented by GPS speed/position measurements are used to track position of a watercraft. Said position estimates are used to allow the locations of prescribed courses to be mapped and memorized. Algorithms are then used to allow the apparatus to automatically detect passage of a watercraft through mapped courses for the purpose of measuring and reporting time of passage of said watercraft past key points in said course, and for modifying the behavior of the speed control portion of the apparatus if necessary at certain points in the mapped course. A measure of accuracy of driver steering can be provided along with the ability to automatically steer the watercraft through the course if “steer-by-wire” mechanism is available. GPS speed control is augmented with a secondary velocity measurement device that measures speed over water resulting in an optional user selectable real-time compensation for water current. Furthermore, GPS is used as the key input to produce boat speed-based pull-up profiles.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an embodiment of external housing of the device of the instant invention.
FIG. 2 is a block diagram of the electronics contained within the housing of FIG. 1 .
FIG. 3 is a feedback control loop diagram demonstrating the operation of an observer in accordance with a preferred embodiment of the present invention.
FIG. 4 is a diagram of an example water body including three ski courses.
FIG. 5 is a flow diagram disclosing a method that an observer in accordance with a preferred embodiment of the present invention may use to determine observed velocity and observed position.
FIG. 6 is a flow diagram disclosing a method for automatically detecting a previously-mapped course.
FIG. 7 is a flow diagram disclosing a method of detecting and reporting the time at which a plurality of events is detected.
FIG. 8 is a flow diagram disclosing a method by which a user interactively “maps” a desired water course, and by which the present invention stores the mapped water course into non-volatile memory.
FIG. 9 is an example of a competitive slalom ski course.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention relates generally to electronic event detectors and more specifically to electronic event detectors for use with power boats.
As show in FIG. 1 , the event detector 100 of the present invention includes a housing 102 for housing the electronics of the invent detector an accelerometer 106 and a GPS 104 . GPS 104 is preferably a unit separate from housing 102 , e.g. a GARMIN® GPS 18-5 Hz.
Electronic housing 102 includes a display 108 and interface buttons 110 . As will be appreciated by one skilled in the art the display 108 is preferably made out of moldable materials such as plastic, aluminum, glass, and the like, with a clear glass or plastic cover. Importantly, the housing is adapted to be waterproof to prevent damage to the electronics when in use. The display 108 may be a commercially available LCD display that is capable of displaying numbers or letters and information related to the event. User interface buttons 110 are actuators attached to the electronics covered in a rubberized membrane that allows buttons to remain waterproof during their actuation. The LCD display interface buttons 110 and glass cover are attached to an insulated housing 102 via e.g., screws, friction fit, adhesive, or the like inside the housing 102 are electronics, to be described below, that perform the functions of the device.
The electronics will now be described with reference to FIG. 2 . In general, the electronics of the event locator device 100 includes microprocessor 200 , non-volatile storage 202 , GPS interface 204 , Clock 206 , speaker 208 , power device 210 , user input interface 214 , accelerometer 216 , and analog-to-digital converter 218 .
Microprocessor 200 is the “brains” of the invention and performs location calculations and timing data for output to a user. Preferably microprocessor 200 is capable of being externally programmed. Volatile storage 202 is connected to microprocessor 200 and stores event data such as map information, location information, and timing information for the microprocessor's calculations. Clock device 206 provides time data to the microprocessor 200 which can be displayed to a user. GPS interface 204 interfaces with the GPS system which provides location data to the microprocessor 200 . Accelerometer 216 generates an acceleration signal and provides the same to the microprocessor 2000 . AC/DC converter converts the signal from the accelerometer to a digital signal for input into the microcontroller 200 . User input interface 214 is connected to the microprocessor and allows the user to program certain device settings into the non-volatile storage 202 such as map information, desired speed, and the like. Display 212 interacts with microprocessor to display event data speed, location and time information. Power supply 210 provides power to microcontroller and all of the associated electronics.
The general operation of microprocessor 200 will now be described in more detail with reference to FIG. 3 . Note FIG. 3 contemplates a scenario where course mapping information is already saved in memory and accessible by the microprocessor. As is shown, the accelerometer receives a signal from the boat indicative of the boat's acceleration and inputs this signal to a microprocessor. The microprocessor converts the acceleration value into a velocity value in step 15 and in step 16 receives both the velocity information from the accelerometer and the velocity data from the GPS. As one skilled in the art will appreciate the velocity from a GPS is not updated continuously, and the velocity information from the accelerometer is used to provide resolution to the velocity information from the GPS system in step 17 . An observed velocity is output at step 17 , and in step 70 the velocity information and direction information obtained from the GPS system is used to calculate a latitude and longitude value for the accelerometer. In step 80 , latitude and longitude information from the GPS system is compared to latitude and longitude information from the accelerometer. Much like step 17 , the latitude and longitude information from the accelerometer is then used to attenuate the GPS signal. The microprocessor then outputs a latitude and longitude observed signal, which is used in reference to map data input by the user at the start of the process. When a preselected event occurs, as calculated by the comparison observed latitude/longitude signals the microprocessor outputs a sound signal to speaker 208 and a display signal to user display 108 .
Collectively, the accelerometer 216 , analog-to-digital converter 218 , computing device 200 , GPS unit 204 , memory 221 and clock 206 comprise the elements of an observer 222 . The observer 222 is adapted to act both as a velocity observer (in which it outputs an observed velocity) and as a position observer (in which it outputs an observed position). In the preferred embodiment of the present invention, an accelerometer acts as the primary source of data for computing displacements over time, with periodic updates from the GPS provided to account for drift in the accelerometer. But it will be appreciated by those skilled in the art that there are many other methods available for performing this task. For example, over-water velocity may be measured directly by means of a transducer such as a paddle wheel or a pitot tube, and those measurements may or may not be corrected with GPS inputs. In the case of direct velocity measurement, only a single integration with respect to time is needed to compute a new position. And, as GPS technology becomes more accurate and as new data are available at a higher frequency, it is conceivable that a GPS unit will provide the sole velocity and position inputs. Other configurations for measuring velocity and position will be apparent to those of ordinary skill in the art, and it is intended for this patent to encompass such additional configurations.
The specific software flow of the microprocessor programming will be described with reference to FIGS. 5 through 8 .
FIG. 5 discloses the functioning of a preferred embodiment of an observer 222 . In step 501 , a GPS signal is received from the GPS device 204 . GPS device 204 provides a GPS position 513 , a GPS velocity 512 , and a GPS direction 511 . Step 501 uses the GPS position as its initial starting position. In Step 502 , there is a check to see if a new GPS position has been received. If a new GPS position has been received, in Step 503 it is checked to see if the GPS position is a valid GPS position. Step 503 compensates for the potential of invalid GPS signals such as occasionally occur in GPS devices known in the art. If the new GPS signal is a valid signal, then the observed position 509 is set to a value of the accelerometer corrected by the difference between the last observed position and the GPS position 513 . A constant 515 is provided such as is calculated to provide the appropriate weight to the GPS measurement. For example, if constant 515 is set to one, then the GPS position is afforded its full weight. If constant 515 is set to a value less than one, the GPS is provided less weight, and it if it set to a value greater than one, the GPS is provided more weight. This constant is selected in accordance with the relative accuracies of the GPS and accelerometer such that for a more accurate GPS device, greater weight can be given to the GPS value and for a less accurate GPS device, less weight can be given to the GPS value. The result of this calculation is an observed position 509 .
It is necessary to compensate for the 5 Hz resolution of the GPS device. This resolution is insufficient for the preferred embodiment of the present invention. So there is provided an alternative device, starting at step 505 , which includes an accelerometer 316 . The accelerometer provides a measured acceleration which is converted to a binary value in analog-to-digital converter 218 . It is then useful for being compared to digital values provided by the GPS device 204 . In step 506 , an observed velocity is computed. The velocity is computed by first taking the last observed velocity 510 and the velocity provided by the GPS 512 . This difference is adjusted by a velocity constant 517 . As with position constant 515 , velocity constant 517 is selected to compensate for the relative accuracy of the GPS device. The weighted difference is then added to the velocity computed by taking the first integral of the acceleration with respect to time, thereby providing a correction factor. In step 507 , an accelerometer-computed position 514 is calculated. This position is computed by taking the integral of the velocity vector with respect to time. The displacement calculated thereby is adjusted to the direction signal provided by the GPS. This GPS correction step is used in the preferred embodiment because, in the interest of simplicity, the three-accelerometer is used only to compute acceleration along the single axis of the length of the boat. The result is accelerometer-computed position 514 . The usefulness of accelerometer-computed position 514 is that it can be calculated at a frequency of approximately 1,000 hertz. So returning to step 502 , if no new GPS signal has been provided, then the observed position is provided by the change in position as calculated by the accelerometer with no further input from the GPS device. Thus, there is provided from the observer an observed position 509 as well as an observed velocity 510 .
FIG. 8 discloses a method of using a watercraft equipped with a position and velocity observer, such as is described in FIG. 5 , to map a competitive water course. In step 801 , there is initial determination of the position and velocity of the watercraft as provided by the observed velocity 510 and the observed position 509 . In step 802 , there is a check to see whether there has been a user input from a map button 214 . If no user input is provided, then the position observer continuously updates the position and velocity of the watercraft. Once there has been a user input at step 803 , the current observed position 509 and the current heading are stored in non-volatile storage 202 . In step 805 , there is provided a step of checking to see if it is desired to map another point. If another point is to be mapped, then there is a return to step 801 and the method is repeated until, at step 805 , there is no further point to mapped. When there is no further point to be mapped, at step 806 , the device may calculate a number of predetermined intermediate points in between the points mapped and stored in step 803 . These intermediate points are also stored in non-volatile storage 202 .
In FIG. 6 , there is disclosed a method of automatically detecting a course that has been mapped in accordance with the method of FIG. 8 . At step 601 , there is initial determination of position and velocity provided by observed position 509 and observed velocity 510 . In step 602 , compare the observed position 509 to a predetermined position as mapped in accordance with the method of FIG. 8 . This mapped position is provided from non-volatile storage 202 . In 603 there is a determination of which of a plurality of mapped courses as mapped in accordance with the method of FIG. 8 is the closest to the present observed position 509 . Once a closest course has been locked in, then, in step 604 , there is a check to see whether the watercraft is inside the lockout region of the closest water course. If the craft is within the lockout region, then there is also a check to see whether the craft is approaching from outside the course and is proceeding in the right direction along the center line of the course. If these criteria are not met, then continue looking for entrance into a course. If the criteria are met, then, in step 606 , check to see whether the craft has crossed the plane of the entry gate of the course. If it has not, then return to step 602 , continuing looking for entry to a course. If the criteria are met, then the craft has entered a mapped course and the course timing algorithm will automatically begin in step 607 . This provides an observed position at the entry point 608 .
In FIG. 7 there is disclosed a method for computing total time and intermediate times through a competitive water course. There is provided an observed position at the entry point 608 and there is also provided a clock signal 206 . In step 701 , the time at the entry point is recorded in temporary memory 221 . In step 702 , an observed position 509 is provided and this provides the present position of the watercraft. A plurality of points of interest are stored in non-volatile storage 202 . In step 703 , a point of interest is provided and there is a check to see if the current observed position 509 exceeds the position of the point of interest. If the present position 509 does not exceed the position of the point of interest, then the loop is continued until the present observed position exceeds the position of the point of interest. At this point, in step 704 , the present observed time 709 is recorded into temporary memory 221 and, in step 705 , the current observed time 709 is displayed on user display 212 . In step 706 , there is provided an ideal time 710 . An error time 711 is computed as the difference between the ideal time 710 and the observed time 709 . The error time 711 is also stored in temporary storage 221 and displayed on user display 212 .
In a parallel process to step 704 , when a point of interest is reached, there is also provided an audible signal through a speaker 208 to provide an audible indication to the user that this point has been passed. After steps 704 , 705 , 706 and 708 are completed, then in step 707 there is a check to see if this is the last point of interest. If it is not, then there is a return to step 702 . If this is the last point of interest, the process ends.
The use of the device will now be described with respect to FIGS. 3 , 4 and 9 .
As diagrammed in FIG. 3 showing feedback system 310 , the inertia measurement device (accelerometer) 216 measures the actual acceleration a a of a watercraft 50 and the GPS device 204 measures the actual velocity v a and position of the same watercraft 50 . The output from the accelerometer a Acc is input into a first step 15 that coverts a Acc to velocity a Acc . The output from first step 15 v Acc and the GPS output v GPS are input to a second step 17 . The output from a second step 17 v OBS and the output (Dir GPS ) indicating course or direction of travel from the GPS device 204 are input into a third step 70 to derive inertial-based estimates of the latitude (Lat Acc ) and longitude (Long Acc ) of the watercraft 50 . Direct GPS measurements of latitude (Lat GPS ) and longitude (Long GPS ) and the outputs from the third step 70 are input in a fourth step 80 to correct inertial-based estimates of the latitude (Lat Acc ) and longitude (Long Acc ) of the watercraft 50 to account for any inaccuracies due to drift or acceleration sensor inaccuracies. Lat OBS and Long OBS can then be used to allow the boat driver to record via a user interface the absolute latitude and longitude position coordinates of a course to be saved into a permanent non-volatile memory. Coordinates can be recorded either by direct numerical entry of measured coordinates, or by snapshotting course coordinates as the boat is maneuvering through the course to be mapped. The driver can identify course reference points via a user interface (not shown) or button press as the boat passes the point to be mapped. Since all courses of interest are laid out in straight lines, mapping of two known points in a course is sufficient to fully define the locations of all points of interest in a course and it's direction relative to earth latitude and longitude coordinates. All future passages of the towboat within a specified distance of selected course coordinates as measured by Lat OBS and Long OBS can then be detected and used to initiate timing measurements of the towboat through the mapped course.
FIG. 9 discloses a competitive slalom ski course. This is the type of course on which an embodiment of the present invention may be used. There is shown an entry gate 901 , which can be characterized by a precise global coordinate specified in latitude and longitude. The opposite end point of the course is exit gate 905 , which may also be characterized as a latitude and longitude. Because the course lies along a substantially straight line, the locations of all points of interest along the course can be found given the positions of the two end points. A course centerline 906 lies along a substantially straight line and is slightly larger than the width of a water craft. The centerline is defined by boat buoys 904 , which the water craft must stay in between. There are also provided ski buoys 902 , which the skier must ski around during the passage of the course, in an alternating pattern as shown by the ski path 903 . The skier must pass between the buoys defining first break point 907 before proceeding along ski path 903 . At the end of the course is a second break point 908 . The skier must ski between the two buoys defining second break point 908 after passing around the last buoy 902 . In between these points are six intermediate points 904 , each defined by a pair of buoys, which are positioned to be substantially collinear with the ski buoys 902 .
The entry gate 901 , exit gate 905 , break points 907 and 908 and intermediate buoys 904 are all points of interest whose passage may need to be detected. The time at which the boat 50 passes these points may be used to determine whether a run is valid, according to whether the time is within an allowable margin of error. Because these points are defined according to precisely-surveyed distances, their locations can be detected by a substantially accurate observer (such as is provided by the preferred embodiment of the present invention) given only the location of the two end points. So the mapping course-mapping method described in FIG. 8 provides the observer with sufficient information to determine when a point of interest has been passed in accordance with the method of FIG. 7 .
Once a course has been mapped, the location of the course can be stored in a permanent storage medium 202 such as a disk drive or flash memory. Further qualification of valid entry to a course can then be carried out based on GPS direction measurements so that timing measurements are only made when the towboat enters a mapped course while traveling along the known direction of the course centerline. Further, any deviations of the tow boat from the center line of the course can be detected and factored geometrically into the measurement of displacement down the centerline of the course so that errors in timing measurement due to driver steering error can be compensated for.
FIG. 4 discloses a water course with a plurality of competitive ski courses. There is disclosed a first slalom course 401 , a second slalom course 402 and a jump course 403 . First slalom course 401 has entry and exit thresholds 405 . Second slalom course 402 has entry and exit thresholds 406 . The slalom courses may be traversed in either direction through entry and exit thresholds 405 and 406 . A jump course 403 may be entered only through entry threshold 411 because ski jump 409 is unidirectional.
According to a preferred embodiment of the present invention, a user may approach a course, for example first slalom course 401 . Upon entering the entry threshold 405 in the direction of the course centerline 408 , the user will press a button whereby the computing device is alerted of the location of the entry/exit threshold. The user then proceeds along course centerline 408 and presses a button again at the opposite entry/exit threshold 405 .
The computing device also interfaces with a permanent storage medium. This storage medium contains the desired locations of intermediate buoys 407 , which are located at predetermined distances from the entry/exit buoys. “This process” allows the computing device to learn the exact location of first slalom course 401 . “The process” can then be repeated to allow the computing device to learn the locations of second slalom course 402 and jump course 409 .
Once the computing device has learned the locations of courses 401 , 402 and 403 , it is desirable for the device to automatically detect which course it is at without further user intervention. So there are shown mapped lockout regions 404 around each of the entry/exit thresholds 405 , 406 and 411 . According to the method disclosed in FIG. 6 , the device will detect which of the mapped courses is closest to its present position. The device may also selectively detect only courses of a specific type (jump or slalom) depending on its current mode of operation. If the device then determines it is within a lockout regions 404 , it will check to see if the boat is approaching from outside the entry/exit threshold and in the correct direction along the course centerline. If these criteria are met, then the device will calculate the time o the closest approach to the plane of the entry gate. At that time it will begin timing the path without any intervention from the user.
Because the locations of intermediate buoys 407 are pre-programmed, the device may provide an audible or visual indication of the passing of each intermediate buoy 407 . It may also provide intermediate times at the passing of each intermediate buoy 407 . Finally, it will calculate the time at which boat 50 passes through the opposite entry/exit threshold 405 .
In this manner the device can automatically time a pass through a memorized course without any further intervention from the user.
A driver score can also be provided based on the degree of this error which can be used to rate driver performance and confirm accuracy of the boat path through the course, which is also a criterion used in judging whether a competitive pass is valid.
Any boat speed or engine torque modification requirements which may depend on position in the course can be triggered based on Lat OBS and Long OBS relative to the mapped course location.
As one skilled in the art will recognize, the device of the invention is one of the category of commonly understood instruments that measures an object's acceleration. The velocity of on object can be calculated by integrating the acceleration of an object over time. Further, the position of an object relative to a known starting point can be calculated by integrating the velocity of an object over time. A GPS device is one of the category of commonly understood instruments that use satellites to determine the substantially precise global position and velocity of an object. Such position and velocity measurements can be used in conjunction with timers to determine an object's instantaneous velocity and average velocity between two points, along with its absolute position at any point in time. A comparator is any analog or digital electrical, electronic, mechanical, hydraulic, or fluidic device capable of determining the sum of or difference between two input parameters, or the value of an input relative to a predetermined standard. An algorithm is any analog or digital electrical, electronic, mechanical, hydraulic, or fluidic device capable of performing a computational process. The algorithms disclosed herein can be performed on any number of computing devices commonly called microprocessors or microcontrollers, examples of which include the Motorola® MPC555 and the Texas Instruments® TMS320.
Use of observed velocity and position estimates based on inertial or other measurement sources allows for error correction of occasional glitches or interruptions in availability of accurate GPS velocity and position measurements. These can occur in the course of normal operations, either due to GPS antenna malfunction, or temporary loss of GPS satellite visibility due to overhead obstruction from bridges or overhanging vegetation and the like.
Other embodiments of the system could include automated steering of the boat down the centerline of the course making use of course location information stored as described in 0014 thru 0016 above. The present invention may be included as part of an electronic closed-loop feedback system that controls the actual angular velocity ωa of a boat propeller, and, indirectly, the actual over land velocity V a of the watercraft propelled by that propeller.
Another embodiment allows the apparatus to track the position of a skier behind the watercraft as he/she traverses the course. This can be achieved by mounting a GPS antenna somewhere on or near the body of the skier and capturing these data concurrently with data from a tow boat mounted antenna. Such GPS antennae can be either wired or wirelessly connected to the main apparatus.
It will be apparent to those with ordinary skill in the relevant art having the benefit of this disclosure that the present invention provides an apparatus for tracking the position and velocity of a watercraft through a prescribed course without the need for measurement aids such as magnets built into the course infrastructure. It is understood that the forms of the invention shown and described in the detailed description and the drawings are to be taken merely as presently preferred examples and that the invention is limited only by the language of the claims. The drawings and detailed description presented herein are not intended to limit the invention to the particular embodiments disclosed. While the present invention has been described in terms of one preferred embodiment and a few variations thereof, it will be apparent to those skilled in the art that form and detail modifications can be made to that embodiment without departing from the spirit or scope of the invention. | An automatic timing measurement system provides a measure of time of passage of a watercraft through a prescribed course. Inertial or other estimates augmented by GPS speed/position measurements are used to track the position of a the watercraft. Position estimates are used to allow the locations of prescribed courses to be mapped and memorized. The passage of a watercraft through mapped courses may be detected for the purpose of measuring and reporting time of passage of the watercraft past key points in the course, and for modifying the behavior of the speed control portion of the apparatus if necessary. A measure of accuracy of driver steering can be provided along with the ability to automatically steer the watercraft through the course. GPS speed control is augmented with a secondary velocity measurement device that measures speed over water resulting in an optional user selectable real-time compensation for water current. | 6 |
[0001] The present application claims the benefit of European Patent Application Serial No. 13191188.5, filed Oct. 31, 2013.
FIELD OF THE INVENTION
[0002] The invention relates to a process for converting oxygenates to olefins and to a method for removing dimethylether from an olefin containing stream produced in an oxygenates to olefins conversion process.
BACKGROUND OF THE INVENTION
[0003] Oxygenate-to-olefin processes are well described in the art. Typically, oxygenate-to-olefin processes are used to produce predominantly ethylene and propylene. An example of such an oxygenate-to-olefin process is described in US Patent Application Publication No. 2011/112344, which is herein incorporated by reference. The publication describes a process for the preparation of an olefin product comprising ethylene and/or propylene, comprising a step of converting an oxygenate feedstock in an oxygenate-to-olefins conversion system, comprising a reaction zone in which an oxygenate feedstock is contacted with an oxygenate conversion catalyst under oxygenate conversion conditions, to obtain a conversion effluent comprising ethylene and/or propylene.
[0004] U.S. Pat. No. 7,238,848 describes a process for processing an olefin-containing product stream made in a methanol to olefins unit that also contains dimethylether. The patent describes a process for separating C1 and C2 hydrocarbons from C3+ hydrocarbons in a first separation step, followed by separating C3 hydrocarbons along with the dimethylether from C4+ hydrocarbons. The C3 hydrocarbons containing dimethylether are sent to a C3 splitter from which a stream comprising propylene with at most trace quantities of dimethylether and a stream comprising propane with the majority of the dimethylether are removed.
SUMMARY OF THE INVENTION
[0005] The invention provides a process for converting oxygenates to olefins comprising: a) contacting an oxygenate containing stream with a molecular sieve catalyst under oxygenate to olefins conversion conditions in a reactor to form an effluent comprising olefins; b) separating C3− hydrocarbons from C4+ hydrocarbons in the effluent; c) separating C1 hydrocarbon and other light gases from C2+ hydrocarbons; d) separating C2 hydrocarbons from the C3 hydrocarbons; e) sending the C3 hydrocarbons to a C3 splitter to separate propylene from propane; f) removing propylene from the C3 splitter; and g) removing propane from the C3 splitter.
[0006] The invention further provides a method for removing dimethylether together with propane from an olefin-containing stream synthesized from methanol comprising: a) separating C3− hydrocarbons along with dimethylether from C4+ hydrocarbons in the olefin containing stream; b) separating C1 hydrocarbon and other light gases from C2+ hydrocarbons; c) separating C2 hydrocarbons from the C3 hydrocarbons and dimethylether; d) sending the C3 hydrocarbons containing dimethylether to a C3 splitter, comprising a first portion on the top half of the C3 splitter and a second portion on the bottom half of the C3 splitter e) removing propylene from the first portion of the C3 splitter so that a propylene product containing at most only traces of dimethylether is obtained; and f) removing propane from the second portion of the C3 splitter, wherein the dimethylether together with the propane is removed from the second portion of the C3 splitter as one stream.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 depicts one embodiment of the separation scheme according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0008] The invention provides a process for separating the products formed in an oxygenate to olefins conversion process and optionally separating any dimethylether in the propane fraction so it is not in the propylene fraction. The invention provides for a separation section that has a depropanizer column before the other hydrocarbon separation columns. This results in separating the hydrocarbons having a carbon number of 3 and lower from the hydrocarbons having a carbon number of 4 or greater in a first step. This separation does not require refrigeration. By carrying out this separation first, the heavier components are removed from the effluent before refrigeration is required to separate out the lighter components. Thus, the heavier components do not need to be cooled and a smaller cold section and lower duties on the refrigeration compressor or compressors can be achieved.
[0009] The oxygenate to olefins process receives as a feedstock a stream comprising one or more oxygenates. An oxygenate is an organic compound that contains at least one oxygen atom. The oxygenate is preferably one or more alcohols, preferably aliphatic alcohols where the aliphatic moiety has from 1 to 20 carbon atoms, preferably from 1 to 10 carbon atoms, more preferably from 1 to 5 carbon atoms and most preferably from 1 to 4 carbon atoms. The alcohols that can be used as a feed to this process include lower straight and branched chain aliphatic alcohols. In addition, ethers and other oxygen containing organic molecules can be used. Suitable examples of oxygenates include methanol, ethanol, n-propanol, isopropanol, methyl ethyl ether, dimethylether, diethyl ether, di-isopropyl ether, formaldehyde, dimethyl carbonate, dimethyl ketone, acetic acid and mixtures thereof. In a preferred embodiment, the feedstock comprises one or more of methanol, ethanol, dimethylether, diethyl ether or a combination thereof, more preferably methanol or dimethylether and most preferably methanol.
[0010] In one embodiment, the oxygenate is obtained as a reaction product of synthesis gas. Synthesis gas can, for example, be generated from fossil fuels, such as from natural gas or oil, or from the gasification of coal. In another embodiment, the oxygenate is obtained from biomaterials, such as through fermentation.
[0011] The oxygenate feedstock can be obtained from a pre-reactor, which converts methanol at least partially into dimethylether and water. Water may be removed, by e.g., distillation. In this way, less water is present in the process of converting oxygenates to olefins, which has advantages for the process design and lowers the severity of hydrothermal conditions to which the catalyst is exposed.
[0012] The oxygenate to olefins process, may in certain embodiments, also receive an olefin co-feed. This co-feed may comprise olefins having carbon numbers of from 1 to 8, preferably from 3 to 6 and more preferably 4 or 5. Examples of suitable olefin co-feeds include butene, pentene and hexene.
[0013] Preferably, the oxygenate feed comprises one or more oxygenates and olefins, more preferably oxygenates and olefins in an oxygenate:olefin molar ratio in the range of from 1000:1 to 1:1, preferably 100:1 to 1:1. More preferably, in a oxygenate:olefin molar ratio in the range of from 20:1 to 1:1, more preferably in the range of 18:1 to 1:1, still more preferably in the range of 15:1 to 1:1, even still more preferably in the range of 14:1 to 1:1. It is preferred to convert a C4 olefin, recycled from the oxygenate to olefins conversion reaction together with an oxygenate, to obtain a high yield of ethylene and propylene, therefore preferably at least one mole of oxygenate is provided for every mole of C4 olefin.
[0014] The olefin co-feed may also comprise paraffins. These paraffins may serve as diluents or in some cases they may participate in one or more of the reactions taking place in the presence of the catalyst. The paraffins may include alkanes having carbon numbers from 1 to 10, preferably from 3 to 6 and more preferably 4 or 5. The paraffins may be recycled from separation steps occurring downstream of the oxygenate to olefins conversion step.
[0015] The oxygenate to olefins process, may in certain embodiments, also receive a diluent co-feed to reduce the concentration of the oxygenates in the feed and suppress side reactions that lead primarily to high molecular weight products. The diluent should generally be non-reactive to the oxygenate feedstock or to the catalyst. Possible diluents include helium, argon, nitrogen, carbon monoxide, carbon dioxide, methane, water and mixtures thereof. The more preferred diluents are water and nitrogen with the most preferred being water.
[0016] The diluent may be used in either liquid or vapor form. The diluent may be added to the feedstock before or at the time of entering the reactor or added separately to the reactor or added with the catalyst. In one embodiment, the diluents is added in an amount in the range of from 1 to 90 mole percent, more preferably from 1 to 80 mole percent, more preferably from 5 to 50 mole percent, most preferably from 5 to 40 mole percent.
[0017] During the conversion of the oxygenates in the oxygenate to olefins conversion reactor, steam is produced as a by-product, which serves as an in-situ produced diluent. Typically, additional steam is added as diluent. The amount of additional diluent that needs to be added depends on the in-situ water make, which in turn depends on the composition of the oxygenate feed. Where the diluent provided to the reactor is water or steam, the molar ratio of oxygenate to diluent is between 10:1 and 1:20.
[0018] The oxygenate feed is contacted with the catalyst at a temperature in the range of from 200 to 1000° C., preferably of from 300 to 800° C., more preferably of from 350 to 700° C., even more preferably of from 450 to 650° C. The feed may be contacted with the catalyst at a temperature in the range of from 530 to 620° C., or preferably of from 580 to 610° C. The feed may be contacted with the catalyst at a pressure in the range of from 0.1 kPa (1 mbar) to 5 MPa (50 bar), preferably of from 100 kPa (1 bar) to 1.5 MPa (15 bar), more preferably of from 100 kPa (1 bar) to 300 kPa (3 bar). Reference herein to pressures is to absolute pressures.
[0019] A wide range of WHSV for the feedstock may be used. WHSV is defined as the mass of the feed (excluding diluents) per hour per mass of catalyst. The WHSV should preferably be in the range of from 1 hr −1 to 5000 hr −1 .
[0020] The process takes place in a reactor and the catalyst may be present in the form of a fixed bed, a moving bed, a fluidized bed, a dense fluidized bed, a fast or turbulent fluidized bed, a circulating fluidized bed. In addition, riser reactors, hybrid reactors or other reactor types known to those skilled in the art may be used. In another embodiment, more than one of these reactor types may be used in series. In one embodiment, the reactor is a riser reactor. The advantage of a riser reactor is that it allows for very accurate control of the contact time of the feed with the catalyst, as riser reactors exhibit a flow of catalyst and reactants through the reactor that approaches plug flow.
[0021] The feedstocks described above are converted primarily into olefins. The olefins produced from the feedstock typically have from 2 to 30 carbon atoms, preferably from 2 to 8 carbon atoms, more preferably from 2 to 6 carbon atoms, most preferably ethylene and/or propylene. In addition to these olefins, diolefins having from 4 to 18 carbon atoms, conjugated or nonconjugated dienes, polyenes, vinyl monomers and cyclic olefins may be produced in the reaction.
[0022] In a preferred embodiment, the feedstock, preferably one or more oxygenates, is converted in the presence of a molecular sieve catalyst into olefins having from 2 to 6 carbon atoms. Preferably the oxygenate is methanol, and the olefins are ethylene and/or propylene.
[0023] The products from the reactor are typically separated and/or purified to prepare separate product streams in a recovery system. Such systems typically comprise one or more separation, fractionation or distillation towers, columns, and splitters and other associated equipment, for example, various condensers, heat exchangers, refrigeration systems or chill trains, compressors, knock-out drums or pots, pumps and the like.
[0024] The recovery system may include a demethanizer, a deethanizer, a depropanizer, a wash tower often referred to as a caustic wash tower and/or quench tower, absorbers, adsorbers, membranes, an ethylene-ethane splitter, a propylene-propane splitter, a butene-butane splitter and the like.
[0025] Typically in the recovery system, additional products, by-products and/or contaminants may be formed along with the preferred olefin products. The preferred products, ethylene and propylene are preferably separated and purified for use in derivative processes such as polymerization processes.
[0026] In addition to the propylene and ethylene, the products may comprise C4+ olefins, paraffins and aromatics that may be further reacted, recycled or otherwise further treated to increase the yield of the desired products and/or other valuable products. C4+ olefins may be recycled to the oxygenate to olefins conversion reaction or fed to a separate reactor for cracking The paraffins may also be cracked in a separate reactor, and/or removed from the system to be used elsewhere or possibly as fuel.
[0027] Although less desired, the product will typically comprise some aromatic compounds such as benzene, toluene and xylenes. Although it is not the primary aim of the process, xylenes can be seen as a valuable product. Xylenes may be formed in the OTO process by the alkylation of benzene and, in particular, toluene with oxygenates such as methanol. Therefore, in a preferred embodiment, a separate fraction comprising aromatics, in particular benzene, toluene and xylenes is separated from the gaseous product and at least in part recycled to the oxygenate to olefins conversion reactor as part of the oxygenate feed. Preferably, part or all of the xylenes in the fraction comprising aromatics are withdrawn from the process as a product prior to recycling the fraction comprising aromatics to the oxygenate to olefins conversion reactor.
[0028] The C4+ olefins and paraffins formed in the oxygenate to olefins conversion reactor may be further reacted in an additional reactor containing the same or a different molecular sieve catalyst. In this additional reactor, the C4+ feed is converted over the molecular sieve catalyst at a temperature in the range of from 500 to 700° C. The additional reactor is also referred to as an OCP reactor and the process that takes place in this reactor is referred to as an olefin cracking process. In contact with the molecular sieve catalyst, at least part of the olefins in the C4+ feed is converted to a product, which includes at least ethylene and/or propylene and preferably both. In addition to ethylene and/or propylene, the gaseous product may comprise higher olefins, i.e. C4+ olefins, and paraffins. The gaseous product is retrieved from the second reactor as part of a second reactor effluent stream.
[0029] The olefin feed is contacted with the catalyst at a temperature in the range of from 500 to 700° C., preferably of from 550 to 650° C., more preferably of from 550 to 620° C., even more preferably of from 580 to 610° C.; and a pressure in the range of from 0.1 kPa (1 mbara) to 5 MPa (50 bara), preferably of from 100 kPa (1 bara) to 1.5 MPa (15 bara), more preferably of from 100 kPa (1 bara) to 300 kPa (3 bara). Reference herein to pressures is to absolute pressures.
[0030] In one embodiment, the C4+ olefins are separated into at least two fractions: a C4 olefin fraction and a C5+ olefin fraction. In this embodiment, the C4 olefins are recycled to the oxygenate to olefins conversion reactor and the C5+ olefins are fed to the OCP reactor. The cracking behavior of C4 olefins and C5 olefins is believed to be different when contacted with a molecular sieve catalyst, in particular above 500° C.
[0031] The cracking of C4 olefins is an indirect process which involves a primary oligomerisation process to a C8, C12 or higher olefin followed by cracking of the oligomers to lower molecular weight hydrocarbons including ethylene and propylene, but also, amongst other things, to C5 to C7 olefins, and by-products such as C2 to C6 paraffins, cyclic hydrocarbons and aromatics. In addition, the cracking of C4 olefins is prone to coke formation, which places a restriction on the obtainable conversion of the C4 olefins. Generally, paraffins, cyclics and aromatics are not formed by cracking They are formed by hydrogen transfer reactions and cyclisation reactions. This is more likely in larger molecules. Hence the C4 olefin cracking process, which as mentioned above includes intermediate oligomerisation, is more prone to by-product formation than direct cracking of C5 olefins. The conversion of the C4 olefins is typically a function of the temperature and space time (often expressed as the weight hourly space velocity). With increasing temperature and decreasing weight hourly space velocity (WHSV) conversion of the C4 olefins in the feed to the OCP increases. Initially, the ethylene and propylene yields increase, but, at higher conversions, yield decreases at the cost of a higher by-product make and, in particular, a higher coke make, limiting significantly the maximum yield obtainable.
[0032] Contrary to C4 olefins, C5 olefin cracking is ideally a relatively straight forward-process whereby the C5 olefin cracks into a C2 and a C3 olefin, in particular above 500° C. This cracking reaction can be run at high conversions, up to 100%, while maintaining, at least compared to C4 olefins, high ethylene and propylene yields with a significantly lower by-product and coke make. Although, C5+ olefins can also oligomerise, this process competes with the more beneficial cracking to ethylene and propylene.
[0033] In a preferred embodiment of the process according to the present invention, instead of cracking the C4 olefins in the OCP reactor, the C4 olefins are recycled to the oxygenate to olefins conversion reactor. Again without wishing to be bound by any particular theory, it is believed that in the oxygenate to olefins conversion reactor the C4 olefins are alkylated with, for instance, methanol to C5 and/or C6 olefins. These C5 and/or C6 olefins may subsequently be converted into at least ethylene and/or propylene. The main by-products from this oxygenate to olefins conversion reaction are again C4 and C5 olefins, which can be recycled to the oxygenate to olefins conversion reactor and olefin cracking reactor, respectively.
[0034] Therefore, preferably, where the gaseous products further include C4 olefins, at least part of the C4 olefins are provided to (i) the oxygenate to olefins conversion reactor together with or as part of the oxygenate feed, and/or (ii) the olefin cracking reactor as part of the olefin feed, more preferably at least part of the C4 olefins is provided to the oxygenate to olefins conversion reactor together with or as part of the oxygenate feed.
[0035] Preferably, where the gaseous products further include C5 olefins, at least part of the C5 olefins are provided to the olefin cracking reactor as part of the olefin feed. Preferably, the olefin feed to the olefin cracking reactor comprises C4+ olefins, preferably C5+ olefins, more preferably C5 olefins.
[0036] In a preferred embodiment, the oxygenate to olefins conversion reactor and the optional OCP reactor are operated as riser reactors where the catalyst and feedstock are fed at the base of the riser and an effluent stream with entrained catalyst exits the top of the riser. In this embodiment, gas/solid separators are necessary to separate the entrained catalyst from the reactor effluent. The gas/solid separator may be any separator suitable for separating gases from solids. Preferably, the gas/solid separator comprises one or more centrifugal separation units, preferably cyclone units, optionally combined with a stripper section.
[0037] The reactor effluent is preferably cooled in the gas/solid separator to terminate the conversion process and prevent the formation of by-products outside the reactors. The cooling may be achieved by use of a water quench.
[0038] Once the catalyst is separated from the effluent, the catalyst may be returned to the reaction zone from which it came, to another reaction zone or to a regeneration zone. Further, the catalyst that has been separated in the gas/solid separator may be combined with catalyst from other gas/solid separators before it is sent to a reaction zone or to the regeneration zone.
[0039] During conversion of the oxygenates to olefins, carbonaceous deposits known as “coke” are formed on the surface of and/or within the molecular sieve catalysts. To avoid a significant reduction in activity of the catalyst, the catalyst must be regenerated by burning off the coke deposits.
[0040] In one embodiment, a portion of the coked molecular sieve catalyst is withdrawn from the reactor and introduced into a regeneration system. The regeneration system comprises a regenerator where the coked catalyst is contacted with a regeneration medium, preferably an oxygen-containing gas, under regeneration temperature, pressure and residence time conditions.
[0041] Examples of suitable regeneration media include oxygen, O 3 , SO 3 , N 2 O, NO, NO 2 , N 2 O 5 , air, air enriched with oxygen, air diluted with nitrogen or carbon dioxide, oxygen and water, carbon monoxide and/or hydrogen. The regeneration conditions are those capable of burning at least a portion of the coke from the coked catalyst, preferably to a coke level of less than 75% of the coke level on the catalyst entering the regenerator. More preferably the coke level is reduced to less than 50% of the coke level on the catalyst entering the regenerator and most preferably the coke level is reduced to less than 30% of the coke level on the catalyst entering the regenerator. Complete removal of the coke is not necessary as this may result in degradation of the catalyst.
[0042] The regeneration temperature is in the range of from 200° C. to 1500° C., preferably from 300° C. to 1000° C., more preferably from 450° C. to 700° C. and most preferably from 500° C. to 700° C. In a preferred embodiment, the catalyst is regenerated at a temperature in the range of from 550 to 650° C.
[0043] The preferred residence time of the coked molecular sieve catalyst in the regenerator is in the range of from 1 minute to several hours, most preferably 1 minute to 100 minutes. The preferred volume of oxygen in the regeneration medium is from 0.01 mole percent to 10 mole percent based on the total volume of the regeneration medium.
[0044] In one embodiment, regeneration promoters, typically metal containing compounds such as platinum and palladium are added to the regenerator directly or indirectly, for example with the coked catalyst composition. In another embodiment, a fresh molecular sieve catalyst is added to the regenerator.
[0045] In an embodiment, a portion of the regenerated molecular sieve catalyst from the regenerator is returned to the reactor, directly to the reaction zone or indirectly by pre-contacting with the feedstock.
[0046] The burning of coke is an exothermic reaction and in certain embodiments, the temperature in the regeneration system is controlled to prevent it from rising too high. Various known techniques for cooling the system and/or the regenerated catalyst may be employed including feeding a cooled gas to the regenerator, or passing the regenerated catalyst through a catalyst cooler. A portion of the cooled regenerated catalyst may be returned to the regenerator while another portion is returned to the reactor.
[0047] In certain embodiments, there is not sufficient coke on the catalyst to raise the temperature of the catalyst to desired levels. In one embodiment, a liquid or gaseous fuel may be fed to the regenerator where it will combust and provide additional heat to the catalyst.
[0048] Catalysts suitable for use in the conversion of oxygenates to olefins may be made from practically any small or medium pore molecular sieve. One example of a suitable type of molecular sieve is a zeolite. Suitable zeolites include, but are not limited to AEI, AEL, AFT, AFO, APC, ATN, ATT, ATV, AWW, BIK, CAS, CHA, CHI, DAC, DDR, EDI, ERI, EUO, FER, GOO, HEU, KFI, LEV, LOV, LTA, MFI, MEL, MON, MTT, MTW, PAU, PHI, RHO, ROG, THO, TON and substituted forms of these types. Suitable catalysts include those containing a zeolite of the ZSM group, in particular of the MFI type, such as ZSM-5, the MTT type, such as ZSM-23, the TON type, such as ZSM-22, the MEL type, such as ZSM-11, and the FER type. Other suitable zeolites are for example zeolites of the STF-type, such as SSZ-35, the SFF type, such as SSZ-44 and the EU-2 type, such as ZSM-48. Preferred zeolites for this process include ZSM-5, ZSM-22 and ZSM-23.
[0049] A suitable molecular sieve catalyst may have a silica-to-alumina ratio (SAR) of less than 280, preferably less than 200 and more preferably less than 100. The SAR may be in the range of from 10 to 280, preferably from 15 to 200 and more preferably from 20 to 100.
[0050] A preferred MFI-type zeolite for the oxygenate to olefins conversion catalyst has a silica-to-alumina ratio, SAR, of at least 60, preferably at least 80. More preferred MFI-type zeolite has a silica-to-alumina ratio, SAR, in the range of 60 to 150, preferably in the range of 80 to 100.
[0051] The zeolite-comprising catalyst may comprise more than one zeolite. In that case it is preferred that the catalyst comprises at least a more-dimensional zeolite, in particular of the MFI type, more in particular ZSM-5, or of the MEL type, such as zeolite ZSM-11, and a one-dimensional zeolite having 10-membered ring channels, such as of the MTT and/or TON type.
[0052] It is preferred that zeolites in the hydrogen form are used in the zeolite-comprising catalyst, e.g., HZSM-5, HZSM-11, and HZSM-22, HZSM-23. Preferably at least 50 wt %, more preferably at least 90 wt %, still more preferably at least 95 wt % and most preferably 100 wt % of the total amount of zeolite used is in the hydrogen form. It is well known in the art how to produce such zeolites in the hydrogen form.
[0053] Another example of suitable molecular sieves are siliocoaluminophosphates (SAPOs). SAPOs have a three dimensional microporous crystal framework of PO2+, AlO2−, and SiO2 tetrahedral units. Suitable SAPOs include SAPO-17, -18, 34, -35, -44, but also SAPO-5, -8, -11, -20, -31, -36, 37, -40, -41, -42, -47 and -56; aluminophosphates (AlPO) and metal substituted (silico)aluminophosphates (MeAlPO), wherein the Me in MeAlPO refers to a substituted metal atom, including metal selected from one of Group IA, IIA, IB, IIIB, IVB, VB, VIB, VIIB, VIIIB and lanthanides of the Periodic Table of Elements. Preferred SAPOs for this process include SAPO-34, SAPO-17 and SAPO-18. Preferred substituent metals for the MeAlPO include Co, Cr, Cu, Fe, Ga, Ge, Mg, Mn, Ni, Sn, Ti, Zn and Zr.
[0054] The molecular sieves described above are formulated into molecular sieve catalyst compositions for use in the oxygenates to olefins conversion reaction and the olefin cracking step. The molecular sieves are formulated into catalysts by combining the molecular sieve with a binder and/or matrix material and/or filler and forming the composition into particles by techniques such as spray-drying, pelletizing, or extrusion. The molecular sieve may be further processed before being combined with the binder and/or matrix. For example, the molecular sieve may be milled and/or calcined.
[0055] Suitable binders for use in these molecular sieve catalyst compositions include various types of aluminas, aluminophosphates, silicas and/or other inorganic oxide sol. The binder acts like glue binding the molecular sieves and other materials together, particularly after thermal treatment. Various compounds may be added to stabilize the binder to allow processing.
[0056] Matrix materials are usually effective at among other benefits, increasing the density of the catalyst composition and increasing catalyst strength (crush strength and/or attrition resistance). Suitable matrix materials include one or more of the following: rare earth metals, metal oxides including titania, zirconia, magnesia, thoria, beryllia, quartz, silica or sols, and mixtures thereof, for example, silica-magnesia, silica-zirconia, silica-titania, and silica-alumina. In one embodiment, matrix materials are natural clays, for example, kaolin. A preferred matrix material is kaolin.
[0057] In one embodiment, the molecular sieve, binder and matrix material are combined in the presence of a liquid to form a molecular sieve catalyst slurry. The amount of binder is in the range of from 2 to 40 wt %, preferably in the range of from 10 to 35 wt %, more preferably in the range of from 15 to 30 wt %, based on the total weight of the molecular sieve, binder and matrix material, excluding liquid (after calcination).
[0058] After forming the slurry, the slurry may be mixed, preferably with rigorous mixing to form a substantially homogeneous mixture. Suitable liquids include one or more of water, alcohols, ketones, aldehydes and/or esters. Water is the preferred liquid. In one embodiment, the mixture is colloid-milled for a period of time sufficient to produce the desired texture, particle size or particle size distribution.
[0059] The molecular sieve, matrix and optional binder can be in the same or different liquids and are combined in any order together, simultaneously, sequentially or a combination thereof. In a preferred embodiment, water is the only liquid used.
[0060] In a preferred embodiment, the slurry is mixed or milled to achieve a uniform slurry of sub-particles that is then fed to a forming unit. A slurry of the zeolite may be prepared and then milled before combining with the binder and/or matrix. In a preferred embodiment, the forming unit is a spray dryer. The forming unit is typically operated at a temperature high enough to remove most of the liquid from the slurry and from the resulting molecular sieve catalyst composition. In a preferred embodiment, the particles are then exposed to ion-exchange using an ammonium nitrate or other appropriate solution.
[0061] In one embodiment, the ion exchange is carried out before the phosphorous impregnation. The ammonium nitrate is used to ion exchange the zeolite to remove alkali ions. The zeolite can be impregnated with phosphorous using phosphoric acid followed by a thermal treatment to H+ form. In another embodiment, the ion exchange is carried out after the phosphorous impregnation. In this embodiment, alkali phosphates or phosphoric acid may be used to impregnate the zeolite with phosphorous, and then the ammonium nitrate and heat treatment are used to ion exchange and convert the zeolite to the H+ form.
[0062] Alternatively to spray drying the catalyst may be formed into spheres, tablets, rings, extrudates or any other shape known to one of ordinary skill in the art. The catalyst may be extruded into various shapes, including cylinders and trilobes.
[0063] The average particle size is in the range of from 1-200 μm, preferably from 50-100 μm. If extrudates are formed, then the average size is in the range of from 1 mm to 10 mm, preferably from 2 mm to 7 mm.
[0064] The catalyst may further comprise phosphorus as such or in a compound, i.e. phosphorus other than any phosphorus included in the framework of the molecular sieve. It is preferred that a MEL or MFI-type zeolite comprising catalyst additionally comprises phosphorus.
[0065] The molecular sieve catalyst is prepared by first forming a molecular sieve catalyst precursor as described above, optionally impregnating the catalyst with a phosphorous containing compound and then calcining the catalyst precursor to form the catalyst. The phosphorous impregnation may be carried out by any method known to one of skill in the art.
[0066] The phosphorus-containing compound preferably comprises a phosphorus species such as PO 4 3− , P—(OCH 3 ) 3 , or P 2 O 5 , especially PO 4 3− . Preferably the phosphorus-containing compound comprises a compound selected from the group consisting of ammonium phosphate, ammonium dihydrogen phosphate, dimethylphosphate, metaphosphoric acid and trimethyl phosphite and phosphoric acid, especially phosphoric acid. The phosphorus containing compound is preferably not a Group II metal phosphate. Group II metal species include magnesium, calcium, strontium and barium; especially calcium.
[0067] In one embodiment, phosphorus can be deposited on the catalyst by impregnation using acidic solutions containing phosphoric acid (H 3 PO 4 ). The concentration of the solution can be adjusted to impregnate the desired amount of phosphorus on the precursor. The catalyst precursor may then be dried.
[0068] The catalyst precursor, containing phosphorous (either in the framework or impregnated) is calcined to form the catalyst. The calcination of the catalyst is important to determining the performance of the catalyst in the oxygenate to olefins process.
[0069] The calcination may be carried out in any type of calciner known to one of ordinary skill in the art. The calcination may be carried out in a tray calciner, a rotary calciner, or a batch oven optionally in the presence of an inert gas and/or oxygen and/or steam
[0070] The calcination may be carried out at a temperature in the range of from 400° C. to 1000° C., preferably in a range of from 450° C. to 800° C., more preferably in a range of from 500° C. to 700° C. Calcination time is typically dependent on the degree of hardening of the molecular sieve catalyst composition and the temperature and ranges from about 15 minutes to about 2 hours.
[0071] The calcination temperatures described above are temperatures that are reached for at least a portion of the calcination time. For example, in a rotary calciner, there may be separate temperature zones that the catalyst passes through. For example, the first zone may be at a temperature in the range of from 100 to 300° C. At least one of the zones is at the temperatures specified above. In a stationary calciner, the temperature is increased from ambient to the calcination temperatures above and so the temperature is not at the calcination temperature for the entire time.
[0072] In a preferred embodiment, the calcination is carried out in air at a temperature of from 500° C. to 600° C. The calcination is carried out for a period of time from 30 minutes to 15 hours, preferably from 1 hour to 10 hours, more preferably from 1 hour to 5 hours.
[0073] The calcination is carried out on a bed of catalyst. For example, if the calcination is carried out in a tray calciner, then the catalyst precursor added to the tray forms a bed which is typically kept stationary during the calcination. If the calcination is carried out in a rotary calciner, then the catalyst added to the rotary drum forms a bed that although not stationary does maintain some form and shape as it passes through the calciner.
[0074] The product recovery section comprises a separation system comprising a series of distillation columns to separate the hydrocarbons into different fractions. Some of the distillation columns are operated at below-ambient temperature conditions and this requires one or more refrigeration compressors. As described, a typical product slate from the oxygenate to olefins conversion contains mainly olefins having from 2 to 6 carbon atoms. The reactor effluent is separated into individual fractions to be recycled to the reaction or to be exported as product streams from the system.
[0075] Propylene and ethylene are the main desired products and it is important to separate these as efficiently and cost-effectively as possible. The process according to this invention provides a more efficient process than that described in the prior art. The process is depicted schematically in FIG. 1 . The reactor effluent is preferably compressed in one or more compression stages where heavier hydrocarbons are condensed so they can be removed before this separation system. The effluent, after optional further compression and/or treating steps is passed to the separation system via line 12 . The effluent is passed first to depropanizer column 10 where the C3 and lighter components are separated from the C4 and heavier components. The C3 and lighter components are passed via line 14 to demethanizer 20 . In the demethanizer, the methane and lighter gases are separated from the C2 and heavier components. The C2 and heavier components are passed via line 26 to deethanizer 40 where the C2 components are separated from the C3 components. The C2 components are passed via line 28 to an ethane-ethylene splitter (not shown) and the C3 components are passed via line 32 to a propane-propylene splitter (not shown). The C4 and heavier components that were separated in the depropanizer are passed via line 18 to debutanizer 30 to separate the C4 components from the C5 and heavier components.
[0076] It is known to one of ordinary skill in the art that the various distillation steps are carried out to make the most efficient separation and that the separation is not carried out to 100% purity in these steps. For example, a small amount of C4 and heavier components may be separated into the C3 and lighter stream or a small amount of C3 and lighter components may be separated into the C4 and heavier stream. This applies to each of the columns described herein. The separations will be carried out with a view to the specification for the various products. For example, polymer grade propylene has a strict specification so the separation of propane and propylene will be carried out to ensure that the propylene is as pure as required by the specification so that additional steps are not needed to bring the propylene on spec.
[0077] In some embodiments, the effluent may comprise trace or small amounts of dimethylether. The dimethylether may be present in an amount of from 1 ppbw to 5 wt % in the effluent from the reactor. As the separation steps are carried out, the dimethylether will tend to concentrate with the C3 components and will be carried into the propane-propylene splitter. The dimethylether will likely be separated with the propane and removed from the splitter. The propylene product specification requires that very little oxygenate be present in the propylene, so it is important that the dimethylether is separated with the propane.
[0078] The separation carried out in the depropanizer column is carried out at or above ambient temperature conditions. The separations carried out in the deethanizer and the demethanizer are typically carried out under below-ambient temperature conditions. These below-ambient temperature separations require refrigeration compressors and other equipment to enable the separations to be efficiently conducted. By passing the effluent to the depropanizer column first, the C4 and heavier components can be removed before the effluent is passed to the refrigeration section. As a result, the refrigeration compressors can be designed with a lower duty and the cold section can be smaller. | A process for converting oxygenates to olefms comprising: a) contacting an oxygenate containing stream with a molecular sieve catalyst under oxygenate to olefms conversion conditions in a reactor to form an effluent comprising olefms; b) separating C3-hydrocarbons from C4+ hydrocarbons in the effluent; c) separating C1 hydrocarbons and other light gases from C2+ hydrocarbons; d) separating C2 hydrocarbons from the C3 hydrocarbons; e) sending the C3 hydrocarbons to a C3 splitter to separate pro pylene from propane; f) removing propylene from the C3 splitter; and g) removing propane from the C3 splitter. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application is a 35 U.S.C. §371 national stage entry of PCT/IL2010/000566, which has an international filing date of Jul. 15, 2010 and claims benefit and priority to U.S. Provisional Patent Application Ser. No. 61/226,158, filed on Jul. 16, 2009, entitled “Infusion Device with Improved Accuracy”, the disclosures of which are herein incorporated by reference in their entireties.
FIELD
The present disclosure relates generally to devices, methods and systems for sustained infusion of fluids and/or analyte sensing. More particularly, the disclosure relates to devices, methods and systems that include a skin securable (e.g., adherable) unit comprising a reusable part and a disposable part. Even more particularly, the present disclosure relates to a two-part skin securable unit utilizing a movable piston pumping mechanism that delivers fluid at a high accuracy rate.
BACKGROUND OF THE DISCLOSURE
Diabetes Treatment
Medical treatment of several illnesses requires continuous drug infusion into various body compartments, such as subcutaneous and intra-venous injections. Diabetes mellitus (DM) patients, for example, require the administration of varying amounts of insulin throughout the day to control their blood glucose levels. In recent years, ambulatory portable insulin infusion pumps have emerged as a superior alternative to multiple daily syringe injections of insulin, initially for Type 1 diabetes patients and consecutively for Type 2 diabetes patients. These pumps, which deliver insulin at a continuous basal rate as well as in bolus volumes, were developed to liberate patients from repeated self-administered injections, and allow them to maintain a near-normal daily routine. Both basal and bolus volumes must be delivered in precise doses, according to individual prescription, since an overdose or under-dose of insulin could be fatal.
Generations of Insulin Pumps and Continuous Glucose Sensors
The first generation of portable insulin pumps refers to a “pager like” device with a reservoir included within a housing and long tubing is required to deliver insulin from the reservoir to the infusion site. Examples of such devices are disclosed in U.S. Pat. Nos. 6,248,093 and 7,390,314. These devices are usually heavy and bulky and the tubing substantially disturbs daily activity.
To avoid the limitations of first generation infusion pumps, an additional concept was proposed, which was implemented in second generation pumps. The additional concept concerns a remote controlled skin adherable device having a bottom surface adapted to be in contact with the patient's skin. The reservoir is contained within a housing and filled using an additional syringe. This paradigm was discussed, for example, in U.S. Pat. Nos. 5,957,895, 6,589,229, 6,740,059, 6,723,072, and 6,485,461. These second generation skin adherable devices still have several drawbacks, the most significant being that the entire device should be disposed of every 2-3 days (due to insertion site infections and reduced insulin absorption) including all the expensive components (electronics, driving mechanism, etc.).
Third generation skin-securable devices were devised to avoid the cost issues of the second generation devices and to extend patient customization. An example of such a device is described in U.S. Patent Application Publication No. 2007-0106218 and in International Patent Application Publication No. WO/2007/052277. This third generation device contains a remote control unit and a skin-securable (e.g., adherable) patch unit that include two parts: (1) a reusable part containing the electronics, at least a portion of the driving mechanism and other relatively expensive components, and (2) a disposable part containing the reservoir. A skin-securable fluid (e.g., insulin) delivery device is also disclosed in U.S. patent application Ser. No. 11/989,681 and in International Patent Application Publication No. WO/2008/012817, the disclosures of which are incorporated herein by reference in their entireties.
A fourth generation infusion device was devised as a dispensing unit that can be disconnected and reconnected to a skin-adherable cradle unit, as disclosed, for example, in U.S. Patent Application Publication No. 2008-0215035 and in International Patent Application Publication No. WO/2008/078318. Such skin-securable dispensing units can be operated using a remote control and/or a user interface (e.g., a button-based interface) provided on a housing of the dispensing unit, as disclosed, for example, in International Patent Application Publication No. WO/2009/013736, filed Jul. 20, 2008, claiming priority to U.S. Provisional Patent Application No. 60/961,527, and entitled “Manually Operable Portable Infusion Device”, and in International Patent Application Publication No. WO/2009/016636, filed Jul. 31, 2008, claiming priority to U.S. Provisional Application Ser. Nos. 60/963,148 and 61/004,019, and entitled “Portable Infusion Device Provided with Means for Monitoring and Controlling Fluid Delivery”, the disclosures of which are incorporated herein by reference in their entireties.
The third and fourth generation dispensing patches can be incorporated with an analyte (i.e. glucose) sensing apparatus enabling continuous readings of analyte levels. Fluid dispensing can be done automatically according to analyte sensing (closed loop system) or semi automatic if the user wishes to control delivery (open loop system). Such dual function sensing and dispensing devices are disclosed, for example, in U.S. Patent Application Publication No. 2007-0191702, the disclosure of which is incorporated herein by reference in its entirety.
Pump Gears and Transmission Error
The pumping mechanism employed in most insulin pumps is a “syringe-like mechanism”, known also as a positive displacement piston pump. In such a pump, a plunger (piston) moves (i.e., slides) within a cylindrical shaped barrel (reservoir), pushing the contents (i.e., drug) out, typically, through a small opening at the end of the reservoir/syringe. The plunger is pushed forward by a drive-screw (plunger rod) that can be integral, rigidly connected, or articulated with the plunger head (piston). The driving mechanism typically consists of a motor and a transmission gear system, which is used to linearly displace the drive-screw either by rotation of the drive-screw, rotation of a drive nut, or rotation of a drive pinion over a rack that serves as a drive-screw (a rack is a toothed bar or rod. Torque is converted to linear force by meshing a rack with a pinion: the pinion turns; the rack moves in a straight line). The transmission gear system is used for reduction of motor revolutions and/or for changing the rotation axis by 90 or 180 degrees, for example.
Typically, the pump's transmission gear system consists of two or more parallel shaft gears (e.g., single stage reduction), comprising two metal cogwheels, integrated with a tooth mesh and both cogwheel shafts are parallel mounted on a metal chassis (gear casing).
Transmission error (hereinafter referred to also as “TE”) is defined as the difference between the actual position of the output gear and the position it would occupy if the gear drive were perfectly conjugated. The equation for TE is expressed as:
TE = θ 2 - ( Z 1 Z 2 ) θ 1
Where Z 1 is the number of teeth of the input gear, Z 2 is the number of teeth of the output gear and θ 1 and θ 2 denote the angular position of the input and output gears in radians, respectively. Essentially, TE is the difference between the actual position of the output shaft of a gear drive and the position that the output shaft of the gear drive would have if the gear drive were perfect, without errors or deflections. The main contributors to transmission error are geometrical errors in alignment (e.g., due to assembly errors/tolerances), tooth profile (e.g., due to manufacturing imperfections/tolerances), elastic deformation of local contacts, and the deflection of the gear shafts and casing due to the transmitted load through and transverse to the gear rotation axis. Depending on its cause, the frequency of the transmission error may be high (i.e., >1 per cycle of the output shaft), or it may be substantially equal to the frequency of the output shaft's rotation (i.e., =1 per cycle of the output shaft). The magnitude of this one per cycle error may depend on load and it may thus be classified as loaded TE.
A consequence of TE existing in transmission gear systems of insulin pumps is inaccuracy in drug delivery. Insulin pumps should deliver basal doses at a very low rate along the entire day with high precision (e.g., 0.05 U/h that is 5 mm 3 /h in case of 100 U/ml rapid acting insulin). Typically, the existence of TE introduces a “sine like” wave to the expected drug delivery linear curve with fluctuations that can substantially affect insulin delivery accuracy and threaten the life of the diabetes patient.
It is understood that TE is may be minimized in gear systems of 1st generation pumps by making gears, gear casings, and bearings robust (e.g., relatively large components, metal components). Consequently these “pager like” pumps are undesirably heavy, bulky, and expensive.
The design goal of skin securable 2nd, 3rd, and 4th generation pumps, however, is that they be small and lightweight, with minimal components and assembly costs. Consequently, the gears, gear casing, and bearings for these pumps are configured to be miniature and lightweight and therefore, they are typically made of plastic (i.e., polycarbonate, polypropylene, etc.). These plastic parts should maintain metal parts' requirements and avoid (or minimize) transmission error. However, plastic parts, especially miniature plastic parts, are typically more subject to manufacturing (e.g., injection molding) and assembly imperfections than metal parts, and are also typically more subject to deformations caused by forces/load applied during routine operation of the pump, all of which are likely to result in transmission error. Transmission error may further be aggravated in 3rd and 4th generation two-part skin securable pumps because the interface between the drive-screw (piston rod) and gear is achieved during connection of the two parts by the user, thus increasing the risk of component misalignment, for example.
Thus, it is desirable to provide a skin securable drug dispensing patch unit which is miniature, discreet, economical for the users and highly cost effective. The patch unit includes a driving mechanism comprising a motor and a gear system with minimized transmission error, for delivering fluids at a high accuracy rate.
It is also desirable to provide a skin securable drug dispensing patch unit that includes two parts, e.g., a reusable part and a disposable part. The disposable part (“DP”) includes a reservoir and a slidable plunger. The reusable part (“RP”) includes electronics, and at least a portion of a driving mechanism including a motor and a gear system with minimized transmission error, for delivering fluids at a high accuracy rate.
SUMMARY
Embodiments of the current disclosure are directed to devices, methods and systems that deliver therapeutic fluid into the body. Some such embodiments may include a syringe type pumping mechanism comprising a barrel reservoir (hereinafter “reservoir” or “barrel”) and a movable/slidable plunger (e.g., piston and gaskets) that moves in a first direction (e.g., forwardly to push fluid out of the reservoir) upon linear movement of a rotating drive-screw. In some embodiments, the drive-screw has a distal end that articulates with the plunger and a proximal end (hereinafter “drive-screw rotator” or “engagement member”) that includes longitudinal ridges (or “teeth”) for engagement with the driving mechanism. In some embodiments, the drive-screw rotator may be substantially cone shaped. The driving mechanism may be comprised of a motor and a transmission/reduction gear system (i.e., a gear system which may function to transmit and/or reduce speed) that rotates the drive-screw.
The gear system may comprise a planetary reduction unit and one or more additional gears. The last gear of the gear system may be configured as a long tube (e.g., cylinder) with external teeth for engagement with an adjacent gear of the gear system and one or more internal teeth for engagement with the drive-screw rotator (this last gear may be referred to hereinafter as “rotating sleeve” or “receiving member”). The length of the rotating sleeve may substantially correspond to the length of the drive screw, or it may be shorter/longer. The rotating sleeve may rotate within a casing that may comprise one or more V-blocks/V-grooves (e.g., front and rear of the casing, in other words, spaced apart along the casing) within the interior of the casing and a supporting spring (or any other biasing element) that forces the rotating sleeve against or adjacent the V-blocks walls. In some embodiments, after engagement of the drive-screw rotator and the rotating sleeve, and upon motor activation, the rotating sleeve rotates the drive-screw rotator.
In some embodiments, the device comprises at least the following three (3) components: a two-part dispensing patch unit (hereinafter “patch unit” or “dispensing unit”), a skin adherable cradle unit (hereinafter “cradle”) and a remote control unit (hereinafter “remote control” or “RC”). In some embodiments, the patch unit can be disconnected and reconnected from and to the cradle. A connecting lumen in the patch unit provides fluid communication between the patch unit and a subcutaneous cannula that is rigidly connected to the cradle. Fluid delivery can be remotely controlled using the RC or using manual buttons/switches located on the patch.
Below is a description of examples of each unit, according to some embodiments:
1—Patch: comprises a pumping mechanism, reservoir and exit port. The patch can be configured as a single part including the reservoir, one or more batteries, electronics, and pumping mechanism or as a two-part unit that comprises:
a. Reusable Part (hereinafter “RP”)—includes motor, gear/s, electronics, and other relatively expensive components. In some embodiments, the RP may be a durable unit/assembly which is replaced every three months, for example. b. Disposable Part (hereinafter “DP”)—includes an exit port, a barrel (reservoir), a plunger, a drive-screw, and a nut. In some embodiments the DP further includes one or more batteries. In some embodiments, the reservoir may include a flat configuration (e.g., oval, ellipse, four arches, etc.) maintaining a thin DP profile. In some embodiments, the DP may be a single-use unit/assembly which is replaced every two-three days, for example. In some embodiments, each of the RP and DP include a housing (shell, or pocket) and an insert (chassis) and upon RP-DP connection the housings and/or inserts are coupled together.
2—Cradle: a typically flat sheet (or plate) having an adhesive layer facing the skin. The cradle may be provided with a passageway to a subcutaneous cannula, and configured for secure connection with the cannula and with the patch. 3—RC: a handheld unit micro-processor based device for programming fluid flows, controlling the patch, data acquisition, and providing indications (e.g., via a display). In some embodiments, the RC may comprise a wrist-watch, cellular phone, PDA, iPhone, iPod, and laptop (and the like).
Thus, it is an object of some of the embodiments of the present disclosure to provide a device/system for medical infusion of fluids into the body that includes a syringe type pumping mechanism and a driving mechanism that comprises a transmission/reduction gear that rotates a drive-screw with minimal transmission error.
It is another object of some of the embodiments of the disclosure to provide an infusion device/system that includes a two-part skin securable patch comprising a reusable part and disposable part. The reusable part includes one or more or all of a motor, gear(s), electronics, and other relatively expensive components and the disposable part includes one or more or all of an exit port, a reservoir, a plunger, and a drive-screw. One or more batteries may reside in the disposable part and/or in the reusable part.
It is another object of some of the embodiments of the disclosure to provide a skin securable patch for sustained medical infusion with controlled rate injection of a fluid into a body.
In some embodiments, a fluid delivery system for delivering a drug into the body of a user is provided. The system may comprise a fluid delivery device which includes a disposable part and a reusable part. The disposable part may comprise a disposable part housing, a reservoir containing the drug, a plunger for displacing the drug from the reservoir to the user and a drive-screw that includes a first end and a second end, the first end being configured to connect to the plunger. In some embodiments, the drive-screw may comprise at least a portion of the driving mechanism. The reusable part may comprise a reusable part housing, at least a portion of a driving mechanism which includes at least a motor and one or more gears, the one or more gears including a rotating sleeve configured to receive the second end of the drive-screw upon connection of the disposable part and the reusable part, a controller for at least controlling operation of the at least a portion of the driving mechanism, and a support casing configured to substantially support the rotating sleeve and enable substantially free rotation of the rotating sleeve therein. The system may further comprise a remote control for at least one of initiating drug delivery, programming the device, acquiring data and communicating with other electronic devices. The system may further comprise a skin securable cradle to hold the device to the skin of the user during use.
In some embodiments, a fluid infusion device for delivering a drug into the body of a user is provided and may include at least one housing, a reservoir for containing the drug, a plunger for displacing the drug from the reservoir to the user, and a drive-screw including a first end and a second end. The first end of the drive screw, in some embodiments, is configured to operatively connect to the plunger. The device may also include a driving mechanism comprising at least a motor and one or more gears, where the one or more gears include a rotating sleeve configured to engage with the second end of the drive-screw, a controller for at least controlling operation of the driving mechanism, and a support casing substantially contained within the housing. In some embodiments, the casing is configured to substantially support the rotating sleeve and enable substantially free rotation of the rotating sleeve therein.
In some embodiments, the relationship between the plunger and the first end of the drive-screw which transfers force and/or motion to the plunger may also be referred to as being configured for operative connection and/or being an operative connection (e.g., “operatively connect”, “operatively connected”, “operative connection”). For example: in some embodiments, such “operative connection” (and the like), may refer to the first end of the drive-screw and the plunger being an integral unit—e.g., being manufactured in one piece; and in some embodiments, operative connection may connote separate elements which are connected, either directly or via one or more other elements.
In some embodiments, the support casing noted above may be further configured to maintain a rotation axis of the rotating sleeve substantially parallel to a rotation axis of at least one other gear of the one of more gears.
In some embodiments, the support casing may be further configured to maintain proper alignment between the rotating sleeve and at least one other gear of the one of more gears. Proper alignment may comprise one or more of substantially parallel positioning and substantially accurate spacing between the rotating sleeve and the at least one other gear of the one of more gears.
In some embodiments, the device as noted above may further comprise a chassis for supporting at least a portion of the driving mechanism and the support casing. The support casing may be integral with the chassis. Moreover, in some embodiments, an interior of the casing may comprise at least one pair of substantially flat surfaces positioned adjacent one another, wherein the surfaces may be positioned relative to one another at an angle less than 180 degrees, less than about 120 degrees, and/or between about 30 degrees and about 120 degrees. In some embodiments, the at least one pair of substantially flat surfaces forms a V-block (or “V-groove”).
In some embodiments, the casing comprises an interior with a shape substantially corresponding to an exterior shape of the rotating sleeve. In some embodiments, the interior includes a predetermined tolerance for enabling substantially free rotation of the rotating sleeve therein.
In some embodiments, the device according to any of the above embodiments may further comprise a biasing member for biasing the rotating sleeve relative to the casing. The biasing member may be used to bias the rotating sleeve relative to the at least one pair of substantially flat surfaces. In some embodiments, the biasing member may comprise a spring.
In some embodiments, the casing may comprise at least a pair of structural supports spaced apart from one another so as to substantially support the length of the rotating sleeve, where each support may include an interior surface which substantially corresponds to a portion of the exterior surface of the rotating sleeve. In some embodiments, at least one of the supports may comprise a substantially annular configuration.
In some embodiments, the casing includes one or more slots for receiving at least a portion of the biasing member (e.g., spring).
In some embodiments, the rotating sleeve, and optionally at least one of chassis and the casing, includes at least one opening to enable monitoring of the position of at least one of the drive-screw and the second end thereof within the rotating sleeve.
In some embodiments, the chassis includes a plurality of alignment surfaces configured to maintain at least one of substantially parallel alignment and substantially accurate spacing between at least two of a rotation axis of the motor, a rotation axis of the one or more gears and a rotation axis of the rotating sleeve. The one or more gears may include a gearbox. The device may further comprise at least one of a latching mechanism and an adhesive configured to maintain contact between the gearbox and one or more of the alignment surfaces. The gearbox may include one or more elastic portions. Upon the one or more elastic portions being forced against the chassis, the gearbox is forced against one or more of the alignment surfaces.
In some embodiments, the one or more gears may include or comprise a planetary gear unit.
In some embodiments, connection between the first end of the drive-screw of the device and the plunger may be an articulated connection.
In some embodiments, the connection between the first end of the drive-screw and the plunger preferably enables substantially free rotation of the first end within the plunger, with rotation of the drive-screw causing, or otherwise resulting in, displacement of the plunger in a linear direction within the reservoir.
In some embodiments, the second end of the drive-screw may be integral with the drive-screw. In other embodiments, the second end of the drive-screw may comprise a member which is separate from the drive-screw and is configured to be assembled with the drive-screw.
In some embodiments, the rotating sleeve of the device may include a plurality of internal grooves and/or teeth extending along at least a portion of the length of the rotating sleeve.
In some embodiments, the second end of the drive-screw of the device may include a plurality of teeth configured to engage with the internal grooves and/or teeth of the rotating sleeve.
In some embodiments, the second end of the drive-screw may further include a plurality of centralizing surfaces between adjacent teeth. The centralizing surfaces may be configured to substantially align the second end with the internal grooves and/or teeth of the rotating sleeve.
In some embodiments, at least one tooth of the plurality of teeth of the second end includes a size and/or shape which is partial to the size and/or shape of the remaining teeth.
In some embodiments, at least a portion of at least one tooth of the plurality of teeth of the second end may be elastic.
In some embodiments, the support casing may be further configured to maintain alignment between a rotation axis of the rotating sleeve and a longitudinal axis (e.g., rotation axis) of the drive screw.
In some embodiments, the following additional features may be included with devices, systems and methods according to the present disclosure as set out above or anywhere herein:
the rotating sleeve comprises a substantially cylindrical configuration; the at least one housing comprises a first housing comprising a reusable part of the device and a second housing comprising a disposable part of the device, and where the reusable part and the disposable part are connectable to each other; the reusable part may comprise at least the controller, the support casing and at least a portion of the driving mechanism including the rotating sleeve; the disposable part may comprise at least the reservoir and the plunger; the disposable part may further comprise the drive-screw, and upon connection between the reusable part and the disposable part, the second end of the drive-screw is received within the rotating sleeve; connection of the reusable part and the disposable part may be configured to enable substantial proper alignment between the rotating sleeve and the second end of the drive-screw; a remote control for at least one of initiating drug delivery, programming the device, acquiring data and communicating with other electronic devices; a skin securable cradle to hold the at least one housing to the skin of the user during use; and at least one of a lubricant and low-friction casing material.
In some embodiments, a fluid infusion device for delivering a drug into the body of a user is provided and may include a disposable part comprising a disposable part housing, a reservoir for containing the drug, a plunger for displacing the drug from the reservoir to the user, and a drive-screw including a first end and a second end, the first end being configured to connect to the plunger. The device may also include a reusable part comprising a reusable part housing, at least a portion of a driving mechanism including at least a motor and one or more gears, where the one or more gears include a rotating sleeve configured to receive the second end of the drive-screw upon connection of the disposable part and the reusable part, a controller for at least controlling operation of the at least a portion of the driving mechanism, and a support casing configured to substantially support the rotating sleeve and enable substantially free rotation of the rotating sleeve therein. The reusable part may further comprise a reusable part chassis contained within the reusable part housing for supporting at least a portion of the driving mechanism and the support casing. Moreover, in some embodiments, the support casing may be integral with the reusable part chassis.
One of skill in the art will appreciate that the term “adjacent”, according to some embodiments, can describe a relationship among two or more different items/members, as touching, or as being in close proximity but spaced apart (i.e, the items described and/or claimed as being adjacent may or may not touch one another).
It is worth noting, that features described in any one or another of the embodiments described above and in the detailed description of disclosure which follows, may be combined, mixed and/or matched with one or another of the disclosed embodiments, and included features thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the embodiments of the present disclosure are described with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements.
FIG. 1 shows a system comprising three units: a remote control unit, which may include an integrated blood glucose monitor, a two-part skin securable dispensing patch unit, and a skin adherable cradle unit, according to some embodiments.
FIGS. 2 a - 2 b show a cross sectional view of the connected ( FIG. 2 a ) and disconnected ( FIG. 2 b ) two part skin securable patch unit, according to some embodiments.
FIG. 3 shows a perspective view of a disconnected two-part dispensing unit that comprises a reusable part and a disposable part, according to some embodiments.
FIG. 4 shows a typical one stage reduction gear system, according to some embodiments.
FIG. 5 shows a transmission gear system. Two intermeshing cogwheels are mounted on two parallel shafts that are aligned by a rigid casing, according to some embodiments.
FIGS. 6 a - 6 c show a transmission gear system. Two intermeshing cogwheels are mounted on two non-parallel shafts, according to some embodiments.
FIGS. 7 a - 7 d show representing graphs of transmission error at various rotational velocities, according to some embodiments.
FIGS. 8 a - 8 b shows a perspective view ( FIG. 8 a ) and a transverse cross sectional view ( FIG. 8 b ) of a rotating sleeve within a tube-shaped casing, according to some embodiments.
FIG. 9 shows a typical bar graph of consecutive bolus deliveries when transmission error exists, according to some embodiments.
FIGS. 10 a - 10 b show a perspective view ( FIG. 10 a ) and a transverse cross sectional view ( FIG. 10 b ) of a rotating sleeve aligned with a V-block casing by an applied external force, according to some embodiments.
FIG. 10 c shows the radial forces (R) acting on the rotating sleeve by the V-Block and the external force (F) that is applied by a spring to maintain constant alignment with the X axis, according to some embodiments.
FIG. 11 shows a partial exploded view of a reusable part including a shell, chassis, rotating sleeve and supporting spring, according to some embodiments.
FIGS. 12 a - 12 b show perspective views of the reusable part chassis before ( FIG. 12 a ) and after ( FIG. 12 b ) assembly of the rotating sleeve and supporting spring, according to some embodiments.
FIGS. 13 a - 13 b show a transverse cross sectional view of the reusable part ( FIG. 13 a ) and a magnified view of the rotating sleeve ( FIG. 13 b ) including the supporting spring, according to some embodiments.
FIGS. 14 a - 14 b show perspective views of the reusable part chassis including the alignment surfaces before ( FIG. 14 a ) and after ( FIG. 14 b ) assembly of the planetary gear and the motor, according to some embodiments.
FIG. 15 shows the motor and planetary gear parallel aligned with the rotating sleeve and the rotating sleeve gear, according to some embodiments.
FIG. 16 shows a transverse cross sectional view of the rotating sleeve and the drive-screw rotator, according to some embodiments.
FIGS. 17 a - 17 f show diagrams of various configurations of the drive-screw rotator, according to some embodiments.
DETAILED DESCRIPTION
FIG. 1 shows a system, according to some embodiments, that may include (at least) the following three (3) components:
Dispensing patch unit 10 (“patch”) for delivery of therapeutic fluid/s to a patient. The patch 10 may be comprised of one or two parts (e.g., a reusable part and a disposable part). In some embodiments, the patch 10 may be disconnected from and reconnected to a skin securable (e.g., adherable) cradle unit 20 (“cradle”). Commands relating to fluid dispensing may be provided, according to some embodiments, via a remote control and/or using buttons/switches located on the patch 10 , as disclosed, for example, in International Patent Application Publication No. WO/2009/013736, and International Patent Application Publication No. WO/2009/016636, the contents of all of which are hereby incorporated by reference in their entireties.
Remote control unit 30 (“remote control”), which may include, in some embodiments, an integrated blood glucose monitor, may also be provided. The remote control 30 may include a screen 32 , a keypad 34 , and a slot 36 to receive a blood test strip 38 . The remote control 30 may be used for patch programming and/or data acquisition, and may also be used for communicating with other electronic devices such as a personal computer (“PC”), to carry out, for example, data downloading and uploading. In some embodiments, the remote control 30 may be configured, without limitation, as a wrist-watch, a cellular phone, a personal digital assistant, iPhone, iPod, or an mp3 player.
Embodiments of the cradle 20 may be configured as a generally flat sheet or plate having a surface that is securable (e.g., adherable) to the skin of a patient, e.g., via an adhesive layer 22 provided on a bottom surface of the cradle 20 . The cradle 20 may also contain a passageway for insertion of a cannula (not shown) into the body. In some embodiments, the cradle 20 may further include connecting means/connectors (e.g., snaps) to rigidly secure the patch 10 and/or cannula to the cradle 20 , as well as ribs, walls, and the like, so as to maintain structural rigidity.
Examples of such a device are disclosed in U.S. Patent Application Publication No. 2008-0215035, International Patent Application Publication No. WO/2008/078318, U.S. Patent Application Publication No. 2007-0106218, International Patent Application Publication No. WO/2007/052277, and International Patent Application Publication No. WO/2009/125398, the contents of all of which are hereby incorporated by reference in their entireties.
U.S. Patent Application Publication No. 2007-0191702, the content of which is hereby incorporated by reference in its entirety, discloses a device that includes a dispensing patch unit (e.g., an insulin dispensing patch) and an analyte sensor (e.g., a continuous glucose monitor). This type of dual function device may have a similar configuration to that outlined above and may also be disconnected from and reconnected to the skin at the patient's discretion.
FIGS. 2 a - 2 b show longitudinal cross sectional views of a two-part dispensing patch unit 10 , according to some embodiments. FIG. 2 a shows the two parts connected, and FIG. 2 b shows the two parts disconnected. In some embodiments, the dispensing patch unit 10 may include a disposable part 200 (“DP”) and a reusable part 100 (“RP”). In some embodiments, the RP 100 may be a durable unit/assembly which is replaced every three months, for example, and the DP 200 may be a single-use unit/assembly which is discarded and replaced every 2-3 days, for example. In other words, a single RP 100 may be coupled to approximately thirty (or more) different DPs 200 throughout its lifetime. The disposable part 200 may include an external housing 210 , a portion of which may also form/define the reservoir 220 , and a chassis (insert) 288 to support DP components including, for example, a battery 240 and an outlet port 213 . A plunger (piston) 235 may be linearly displaced within the reservoir 220 by a drive-screw (plunger rod) 230 , that may be integral with the plunger 235 or connected/coupled to the plunger 235 via a distal end of the drive-screw. The drive screw (plunger rod) 230 may further include a proximal end configured as a drive-screw rotator 232 . The drive-screw rotator 232 may be integral with the drive-screw 230 or attached (e.g., glued) to the drive-screw 230 . The reusable part 100 may include an external housing 110 , and a chassis (insert) 188 to support the RP components including, for example, electronics 150 (e.g., attached to a PCB) and at least a portion of a driving mechanism. The driving mechanism may include a motor 130 and a transmission/reduction gear system. Such gear system may include a gearbox 131 , which may comprise a planetary unit. The term “gearbox” may be used hereinafter to describe either a shell/housing with at least one gear enclosed therein, or the shell/housing alone. In some embodiments, the gear system may further include one or more additional gears, e.g., gear 162 , which meshes with one or more gears of the gearbox, e.g., gear 134 . Gear 162 may be coupled to, or integral with, a rotating sleeve 160 for engagement with the drive-screw rotator 232 of the DP 200 . During DP-RP connection, in some embodiments, the drive-screw rotator 232 is received by the rotating sleeve 160 . The rotating sleeve 160 may be enclosed within a casing 40 configured to support the rotating sleeve 160 and maintain alignment of the rotating sleeve 160 and the rotating sleeve gear 162 with the longitudinal axis of the device and/or with the longitudinal axis (e.g., the axis of rotation) of a component of the device (e.g., gear 134 ). The casing 40 may be part of the RP chassis 188 or it may be a separate component/structure. In some embodiments, the casing 40 may include one or more pieces attachable to (e.g., using glue or ultrasonic welding), or integral with, the RP chassis 188 . Two operating buttons 15 (e.g., bolus buttons) may be provided on the RP housing 110 for issuing commands related to fluid delivery, for example.
FIG. 3 shows a further embodiment of a patch 10 comprised of two parts—a reusable part 100 and a disposable part 200 . The reusable and disposable parts may each be comprised of one or more housings (interchangeably wording with “shell” or “pocket”) and chassis (interchangeably wording with “insert”). The chassis may be used as a support structure (“skeleton”) for attachment of components within the housing. The pumping mechanism may be “syringe-like” and may include a sliding plunger 235 within a barrel (i.e., a reservoir) 220 , which may be cylindrical or oval, for example. The RP 100 may include the relatively expensive components including (but not limited to) a motor 130 , gear system including a gearbox 131 and rotating sleeve 160 , electronics 150 , and operating buttons 15 , e.g., to manually deliver fluid without the aid of the remote control (also referred-to as “bolus buttons”). The DP 200 may include the reservoir 220 , the plunger 235 with one or more gaskets 237 , a threaded plunger rod (“drive-screw”) 230 that may have a distal end articulating with the plunger 235 and a proximal end that is engaged with the rotating sleeve 160 after RP-DP connection. The proximal end may be configured as a drive-screw rotator 232 (or “engagement member”). The DP 200 may further include an engagement nut 209 (hereinafter “nut”), an exit port 213 and, in some embodiments, one or more batteries 240 . The DP exit port 213 may include a connecting lumen (not shown) that, in some embodiments, maintains fluid communication between the reservoir 220 and the body, e.g., via a cannula (not shown) inserted in the subcutaneous tissue. A delivery tube 250 may be used to connect the reservoir 220 to the connecting lumen. Forward motion of the plunger 235 urges fluid from the reservoir 220 into the delivery tube 250 . In some embodiments, the reservoir's cross-section is oval/elliptical, or it may include a plurality of arches (e.g., four or eight arches) to maintain a thin profile of the patch. The DP 200 includes a shell (pocket) 210 to house internal components. A portion of the DP shell 210 may also define the reservoir 220 (i.e., serve as one or more walls of the reservoir 220 ). The DP “insert” 288 , in some embodiments, supports at least one of and preferably all of the delivery tube 250 , connecting lumen and one or more batteries 240 , and it may also serve as a construction reinforcing means.
FIG. 4 shows a transmission/reduction gear system, according to some embodiments, that comprises two intermeshing cogwheels (gears) 702 and 706 and shafts 704 and 708 . In this example, rotation of the input shaft 704 and the input gear 702 causes rotation of the output gear 706 and the output shaft 708 at a slower rate (i.e., when the smaller gear 702 has completed one revolution the larger gear 706 will have completed less than one revolution).
FIG. 5 shows a transmission/reduction gear system 800 , according to some embodiments, that comprises two intermeshing cogwheels (gears) 802 and 806 mounted on shafts 804 and 808 , respectively. In this example, the intermeshing cogwheels 802 and 806 have the same number of teeth, and the shafts 804 and 808 are parallel to each other, which may be established by a casing (housing) 810 . In this situation, and according to some embodiments, rotation of one shaft (the input shaft) will result in equal rotation of the other shaft (output shaft). Free rotation of the shafts within the casing may be maintained by bearings (not shown) or lubrication means (i.e., greasing), for example.
FIG. 6 a shows a transmission/reduction gear system 900 , according to some embodiments, that comprises two intermeshing cogwheels (gears) 902 and 906 mounted on shafts 904 and 908 , respectively. In this example, the intermeshing cogwheels 902 and 906 have the same number of teeth, however casing 910 does not maintain the shafts 904 and 908 parallel to each other. In this situation, and according to some embodiments, rotation of one shaft (input shaft) will not result in equal rotation of the other shaft (output shaft), i.e., transmission error exists.
FIGS. 6 b and 6 c show an upper view ( FIG. 6 b ) and a magnification of meshing cogwheels 902 and 906 ( FIG. 6 c ) of a misaligned transmission gear system 900 that consequently causes transmission error. Shafts 904 and 908 in this example are not parallel. It will be noted that misalignment of shafts may refer not only to the angle between the shafts, as shown in FIGS. 6 a - 6 c , but also to the distance/space between the shafts. In some embodiments, gear teeth geometry (e.g., involute teeth) and/or dimensions dictate the required spacing (i.e., accurate spacing) between the gear shafts (i.e., between the rotation axis of the gears) to ensure continuous and accurate angular movement of the gears. If the shafts are positioned too close to one another or too far from one another, this may lead to improper meshing of the respective gear teeth, resulting in transmission error.
In addition to misalignment of shafts, which may be a result of assembly errors and/or of forces applied on the shafts/gears, transmission error may be a consequence of the following:
Faulty bearings—an imperfect interface between a shaft and its bearing/s may result in eccentricity/wobbling of the shaft. For example, in the device shown in FIGS. 2 a - 2 b , an imperfect interface between the rotating sleeve 160 and the casing 40 may lead to eccentricity/wobbling of the rotating sleeve 160 within the casing 40 ; and/or Faulty gear teeth—teeth not equally distributed along the circumference of a gear, teeth having different length and shape, etc.; and/or Faulty shaft/s—deformed shaft/s (e.g., curved), etc.
FIGS. 7 a - 7 d show representative graphs of transmission error at various rotational velocities. The X axis represents a single revolution (cycle) of the output shaft/gear and the Y axis is the transmission error. In some embodiments, the low frequency wave (“carrier wave”) is at a frequency of one wave per cycle of the output shaft. This low frequency transmission error may represent eccentricity of the output shaft, which may be a consequence of a faulty interface between the output shaft and its bearing/s, for example. The high frequency wave/s may be related to faulty gear teeth, for example. It can be seen that at high velocities the high frequency waves are diminished (i.e., their amplitude significantly decreases) because the effect of damaged teeth, for example, is relatively negligible.
FIGS. 8 a - 8 b show a perspective view ( FIG. 8 a ) and a transverse cross sectional view ( FIG. 8 b ) of the rotating sleeve 160 , according to some embodiments. The sleeve 160 may be configured as an elongated substantially hollow shaft (e.g., cylindrical) 161 with a gear 162 at its proximal end. The inner part of the sleeve 160 may include longitudinal teeth (ridges) 164 occupying, in some embodiments, the entire length of the sleeve 160 . In some embodiments, the longitudinal teeth 164 define longitudinal grooves 165 for receiving the drive-screw rotator 232 . In some embodiments, the gear 162 is meshed with gear 134 (shown, for example, in FIG. 15 ) and is the last stage of the reduction gear system. The inner teeth 164 may engage with the drive-screw rotator 232 (shown, for example, in FIG. 3 ) upon connection of the reusable and disposable parts (shown, for example, in FIG. 3 ). In some embodiments, the rotating sleeve 160 (or at least a portion of its shaft 161 ) may be positioned within a sleeve housing/casing 40 . The sleeve housing 40 may be configured as a tube, as shown in FIG. 8 a . In some embodiments, the sleeve housing 40 may be configured as two (or more) supports (not shown) located at the two shaft ends, for example. These two or more supports may have a substantially annular configuration or any other configuration suitable for supporting the shaft 161 . FIG. 8 b shows the rotating sleeve 160 within the sleeve housing 40 . A space 14 ′ may be present between the rotating sleeve 160 and the sleeve housing 40 as a result of predetermined tolerances to enable free rotation of the sleeve 160 within the housing 40 (according to some embodiments), and/or as a result of undesired manufacturing tolerances of the sleeve 160 and/or of the casing 40 . This space 14 ′ may allow undesired wobbling motion of the sleeve 160 within the casing 40 resulting in eccentricity of the rotating sleeve 160 and variable friction forces between the sleeve 160 and the casing 40 .
FIG. 9 shows an example bar graph of consecutive bolus deliveries of a dispensing unit having a rotating sleeve, when transmission error exists. The X axis represents the number of bolus deliveries, and the Y axis represents the bolus size (in insulin units). In this example, each initiated bolus delivery should have resulted in the delivery of 0.1 U of insulin. However, the presence of transmission error/s leads to variability in the delivered insulin amounts, characterized by a low frequency sine wave as well as high frequency sine wave/s. In this example, the frequency of the low frequency sine wave corresponds to one full rotating sleeve rotation cycle. Thus, this sine wave may be the consequence of a transmission error related to the rotating sleeve and/or its interfaces with other components (e.g., gear 134 and/or the drive-screw rotator 232 in FIG. 2 ). In some embodiments, rotation of the rotating sleeve rotates the drive-screw rotator and thus the drive-screw, and the rotation of the drive-screw is consequently converted to linear motion of the drive-screw and the plunger within the reservoir, e.g., due to engagement of the drive-screw with a non-rotating nut. Thus, transmission errors related to the rotating sleeve, e.g., imperfect interface between the rotating sleeve and its casing (e.g., a tube-like casing, as shown in FIG. 8 a ) and/or imperfect interface between the drive-screw rotator and the rotating sleeve, may cause variations in the rotation of the drive-screw leading to variations in the linear movement of the piston, and consequently to cyclic variations in delivered bolus amounts corresponding to the rotating sleeve's cycle.
FIGS. 10 a - 10 b show a perspective view ( FIG. 10 a ) and a transverse cross sectional view ( FIG. 10 b ) of an embodiment of a rotating sleeve casing 140 , which is configured (for example) as a V-block. The rotating sleeve 160 may be aligned with the V-block casing 140 by an applied external force (F). In some embodiments, the V-block/section includes at least a pair of walls having corresponding surfaces provided at an angle to one another thereby establishing a “trough” for holding the rotating sleeve. In some embodiments, the angle may be less than 180 degrees, and in some embodiments the angle may be less then 120 degrees. In some embodiments, the angle may be between 30 and 120 degrees, e.g., 90 degrees. In addition, according to some embodiments, the V-block, and corresponding surfaces, may be divided into a plurality of V-blocks/surfaces (e.g., two, three), which may be distributed such that the combined blocks/surfaces support a substantial portion of the length of the rotating sleeve. When the rotating sleeve 160 is forced against the walls of the V-shaped casing 140 , there is little, and in some embodiments, no wobbling motion of the rotating sleeve 160 within the casing 140 , thus the friction forces between the rotating sleeve 160 and the casing 140 are maintained substantially constant and stable. Further, the longitudinal axis of the rotating sleeve 160 is maintained aligned (angle and distance) with the longitudinal axis (e.g., rotation axis) of engaging gears (e.g., gear 134 shown in FIG. 11 ), with undesired manufacturing tolerances of the rotating sleeve 160 (e.g., slightly smaller/larger diameter) having minimal, and in some embodiments negligible, effect. FIG. 10 b shows the rotating sleeve 160 , the gear 162 at its proximal end, and the inner teeth 164 . An external force (arrow) may be applied in this example by a biasing member, for example spring 190 , that, in some embodiments, forces/biases (e.g., presses) the sleeve 160 against walls 1401 and 1402 of the V-block casing 140 (hereinafter in some embodiments referred to as the “spring loaded mechanism”). FIG. 10 c shows the counter radial forces (R) acting on the rotating sleeve 160 by the walls of the V-shaped casing 140 and the external force (F) that is applied by the spring 190 , for example, to maintain constant alignment of the rotating sleeve 160 with the X axis (corresponding to the longitudinal axis of the patch unit, for example).
FIG. 11 shows a partial exploded view of an example reusable part 100 . Shown are reusable part components, including the shell 110 , chassis 188 , rotating sleeve 160 and supporting spring 190 . Two operating buttons/switches (e.g., bolus buttons) 15 may be positioned one on each side of the shell 110 and a protective shield 111 may be connected to the shell's upper side, according to some embodiments. The insert 188 may support one or more of: electronics, motor (not shown), gearbox 131 , and the rotating sleeve 160 with the rotating sleeve gear 162 . The rotating sleeve 160 may be supported by a casing 340 , which may be either coupled to the chassis 188 or integral with the chassis 188 . In some embodiments, the casing 340 includes at least one V-block section, and the rotating sleeve 160 is forced against the V-block walls/surfaces (not shown in FIG. 11 ) by spring 190 . The spring 190 may be positioned within one or more slots, e.g., slot 192 , in the chassis 188 and/or in the casing 340 . In some embodiments, the rotating sleeve 160 may include at least one opening 166 , to allow monitoring of the position of the drive-screw and/or the drive-screw rotator (both not shown in FIG. 11 ) within the rotating sleeve 160 , in order to provide an “end of reservoir alert”, as disclosed, for example, in International Patent Application Publication No. WO/2009/125398. In case the sleeve casing 340 surrounds the entire length of the sleeve 160 (e.g., a tube-shaped casing), or at least the portion of the sleeve 160 having the at least one opening 166 , the casing 340 may include at least one opening (not shown in FIG. 11 ) corresponding to the at least one opening 166 of the sleeve 160 . In some embodiments, the spring 190 may be a separate piece made of bent metal or plastic. In some embodiments, the spring 190 may be a flexible extension of the insert 188 and/or the casing 340 (e.g., molded as one part with the insert 188 and/or the casing 340 ).
FIGS. 12 a - 12 b show perspective views of the reusable part chassis (insert) 188 before ( FIG. 12 a ) and after ( FIG. 12 b ) assembly of the rotating sleeve 160 and the supporting spring 190 within the chassis 188 , according to some embodiments. The chassis 188 may include a distal end 186 configured to be connected to the DP shell (not shown) and a proximal end 189 configured to support one or more or all of the electronics, buzzer, motor, gear, sensor, and capacitor, and to be received by the RP shell (not shown in FIGS. 12 a - 12 b ). One or more gaskets, e.g., gaskets 187 and 187 ′, may be connected/coupled to the chassis 188 to maintain sealing with both the RP shell and the DP shell, respectively. These gaskets 187 and 187 ′ may be glued to the chassis 188 or over-molded after, chassis molding. A portion of the chassis 188 may serve as the rotating sleeve casing 340 (i.e., the chassis 188 and the casing 340 may be manufactured as a single part). The casing 340 may include a pair of substantially flat walls/surfaces 3401 and 3402 , which are provided at an angle relative to one another so as to form together (or function as) a V-block/section (or “V-groove”). In some embodiments, the angle between the two walls/surfaces 3401 and 3402 (which is equal to the angle between the perpendiculars to the walls/surfaces) may be less than 180 degrees, and in some embodiments the angle may be less then 120 degrees. In some embodiments, the angle may be between 30 and 120 degrees, e.g., 90 degrees. In some embodiments, the walls/surfaces 3401 and 3402 may be the contact areas between the rotating sleeve 160 and the casing 340 . As noted above, in some embodiments, the casing 340 may include two or more V-blocks/sections (e.g., front and rear of the casing 340 ). The casing 340 and/or the chassis 188 may include slots, e.g., a lower slot 192 and an upper slot 193 to receive and fixate the supporting spring 190 . At least one slot, e.g., slot 193 , may be configured to allow access of the spring 190 to the rotating sleeve 160 , so that the spring 190 may apply force on the rotating sleeve 160 against the V-block/s (spring loaded mechanism). In some embodiments, the force applied on the rotating sleeve gear 162 by an engaging gear (e.g., gear 134 shown in FIG. 11 ) may also be utilized for pressing the rotating sleeve 160 against the V-block/s.
FIGS. 13 a - 13 b show a transverse cross sectional view of the reusable part 100 ( FIG. 13 a ) and a magnified view of the rotating sleeve 160 ( FIG. 13 b ) including the supporting spring 190 . The dispensing patch unit may be connected to a cradle 20 that is secured to the body (e.g., using an adhesive tape 22 ). The reusable part 100 may include a shell 110 and a chassis 188 . The chassis 188 may support the gearbox 131 and other transmission/reduction gears (not shown). A portion of the chassis 188 may serve as the rotating sleeve casing 340 and may also be configured to receive and fixate the spring 190 . According to some embodiments, the rotating sleeve 160 rotates within the casing 340 and is forced toward one or more V-blocks of the casing 340 , e.g., the V-block composed of walls 3403 and 3404 , by the spring 190 , which penetrates the casing 340 through a dedicated slot (e.g., the slot designated by numeral 193 in FIG. 12 a ). The portion of the spring 190 which penetrates the casing 340 is shown in phantom lines in FIGS. 13 a - 13 b . Further shown in FIGS. 13 a and 13 b is the positioning of the drive-screw rotator 232 within the rotating sleeve 160 when the DP 200 is connected to the RP 100 .
FIG. 14 a shows a perspective view of the RP chassis (insert) 188 before assembly of the motor and the gearbox, according to some embodiments, and with the rotating sleeve 160 in place. The chassis 188 may include multiple alignment surfaces 171 , 172 , 173 , 174 , 175 , 176 , 177 to maintain parallel alignment (or at least substantially so) and accurate spacing (or at least substantially so) between the longitudinal axis (or rotation axis) of the motor and gearbox 131 (not shown in FIG. 14 a ) and the longitudinal axis (or rotation axis) of the rotating sleeve 160 , or at least between the longitudinal axis (or rotation axis) of gear 134 (not shown in FIG. 14 a ) and the longitudinal axis (or rotation axis) of the rotating sleeve 160 . In some embodiments, the gearbox 131 may be pressed against one or more of the alignment surfaces 171 - 177 using latches/snaps and/or an adhesive. In some embodiments, the shell/casing of the gearbox 131 may include at least one relatively elastic portion (e.g., a crush rib) which, when pressed against the chassis 188 , presses the gearbox 131 against one or more of the alignment surfaces 171 - 177 . FIG. 14 b shows the RP chassis 188 after assembly of the motor (not shown in FIG. 14 b ) and the gearbox 131 , in addition to the rotating sleeve gear 160 .
FIG. 15 shows an example driving mechanism of a patch unit, according to some embodiments, including the motor 130 , the gearbox 131 , and the rotating sleeve 160 with its gear 162 . In some embodiments, the gearbox 131 may comprise a planetary unit 132 and one or more additional gears 134 (e.g., reduction gear/s, idler gear/s) between the rotating sleeve gear 162 and the planetary unit 132 . The longitudinal axis (rotation axis) of the rotating sleeve 160 and its gear 162 is parallel aligned (or at least substantially so) with the longitudinal axis (rotation axis) of the motor 130 and the planetary unit 132 and with the longitudinal axis (rotation axis) of the gear 134 .
FIG. 16 shows a transverse cross sectional view of the rotating sleeve 160 and a drive-screw rotator 232 positioned therein. The drive-screw rotator 232 may include a varying number of teeth (ridges), e.g., four teeth 24 . The teeth 24 of the drive-screw rotator 232 engage with the teeth 164 of the rotating sleeve 160 such that rotation of the sleeve 160 rotates the drive-screw rotator 232 , and thus the drive-screw (not shown in FIG. 16 ), since the drive-screw rotator 232 is either integral with the drive-screw or rigidly attached to the drive-screw. It will be noted that the drive-screw rotator 232 does not rotate relative to the sleeve 160 . Unlike the interaction between two engaging gears, where rotation of one gear causes the other gear to rotate in the opposite direction as a result of meshing of the gear teeth, engagement of the drive-screw rotator teeth 24 with the sleeve teeth 164 causes the drive-screw rotator 232 , and thus the drive-screw 230 , to rotate together with the sleeve 160 , in the same direction. The sleeve teeth 164 “push/pull” the rotator teeth 24 along with them as they rotate, allowing only linear relative movement between the drive-screw rotator 232 and the sleeve 160 . As shown in FIG. 16 , the drive-screw rotator 232 may include surfaces 25 (“centralizing surfaces”) between adjacent rotator teeth 24 for ensuring proper alignment between the rotator 232 and the sleeve 160 by maintaining contact with the upper portions of the sleeve teeth 164 . Depending on the embodiment, each centralizing surface 25 may maintain contact with the upper portion of one or more teeth 164 of the rotating sleeve 160 .
FIGS. 17 a - 17 f show perspective views of the drive-screw 230 and various configurations of the drive-screw rotator 232 , according to some embodiments. FIG. 17 a shows the drive-screw 230 and the drive-screw rotator 232 , which may be integral with the drive-screw 230 or attached (e.g., glued) to the drive-screw 230 . FIG. 17 b shows a rotator 2321 having a plurality of “full” teeth (“ridges”) 35 , which may extend from the tip of the drive-screw rotator 232 to its base, and one or more “partial” teeth 36 , e.g., one “partial” tooth 36 between every two adjacent “full” teeth 35 , which may stem from the tip of the drive-screw rotator 232 , similar to the “full” teeth 35 , but terminate before reaching the base of the rotator 232 , according to some embodiments. The “full” teeth 35 may be used for both guiding the drive-screw rotator 2321 into the rotating sleeve (not shown in FIG. 17 b ) and engaging with the teeth of the rotating sleeve to enable rotation of the drive-screw upon rotation of the rotating sleeve. In some embodiments, the “partial” teeth 36 are used for guiding the drive-screw rotator 2321 into the rotating sleeve (i.e., to further facilitate the proper insertion of the drive-screw rotator 2321 into the rotating sleeve 160 ). In some embodiments, the “partial” teeth 36 do not engage with the teeth of the rotating sleeve so as to enable rotation of the drive-screw upon rotation of the rotating sleeve, because their small size and/or length prevents them from maintaining contact with the sleeve teeth. FIG. 17 c shows a rotator 2322 having three teeth, where one tooth 28 is flexible to provide a spring mechanism such that when the rotator 2322 is inserted into the sleeve 160 the spring-like tooth 28 secures the rotator 2322 in place and prevents any undesired wobbling of the rotator 2322 within the sleeve 160 , according to some embodiments. FIG. 17 d shows a rotator 2323 having a plurality of teeth (e.g., eight) substantially evenly distributed along the circumference of the rotator 2323 , according to some embodiments. FIG. 17 e shows a rotator 2324 having three teeth, according to some embodiments. FIG. 17 f shows a rotator 2325 having four teeth, according to some embodiments.
Any and all references to publications or other documents, including but not limited to, patents, patent applications, articles, books, etc., presented in the present application, are herein incorporated by reference in their entirety.
Although particular embodiments have been disclosed herein in detail, this has been done by way of example for purposes of illustration only, and is not intended to be limiting with respect to the scope of the embodiments of the present disclosure. In particular, it is contemplated that various substitutions, alterations, and modifications may be made without departing from the spirit and scope of any embodiment disclosed herein. Moreover, other aspects, advantages, and modifications are considered to be within the scope of the disclosed embodiments. | Embodiments of the present disclosure are directed to devices, systems and methods for increasing the accuracy of delivery of a fluid/drug in a fluid/drug delivery device/system. In some embodiments, a fluid infusion device is provided for delivering a drug into the body of a user, and includes at least one housing, a reservoir, a plunger and a drive-screw, where the drive-screw includes a first end and a second end, the first end being configured to operatively connect to the plunger. The device may further include a driving mechanism comprising at least a motor and one or more gears, where the one or more gears include a rotating sleeve configured for engagement with the second end of the drive-screw, a controller for at least controlling operation of the driving mechanism, and a support casing configured to substantially support the rotating sleeve and enable substantially free rotation of the rotating sleeve therein. | 0 |
TECHNICAL FIELD
The invention relates to polyurethanes which are useful as potting and sealing compounds for biomedical devices, particularly for applications where moisture, water or glycerine will be encountered during the assembly of such devices.
BACKGROUND ART
In the past, polyurethane compositions based on an isocyanate-terminated prepolymer comprising the reaction product of a polyol and a polyisocyanate cured with one or more polyfunctional crosslinking agents have been described in the art. Of particular concern herein are polyurethanes based on prepolymers comprising the reaction product of long chain fatty acid esters such as castor oil with organic polyisocyanates.
For example, in U.S. Pat. No. 3,362,921 to Ehrlich et al, curing agents for prepolymers based on the reaction product of active hydrogen-containing compounds such as castor oil, polyester amides and polyalkylene ether glycols with organic diisocyanates are described. These agents are esters of polyhydric alcohols containing at least four hydroxy groups and an aliphatic acid having at least 12 carbon atoms and one or more hydroxy and/or epoxy groups. The cured polyurethanes find use as flocking adhesives, paper coatings, potting compositions and encapsulating compounds for electronic parts.
U.S. Pat. No. 3,483,150 to Ehrlich et al. discloses prepolymer compositions which are the reaction product of at least one polyfunctional compound containing active hydrogens with an arylene diisocyanate and a low viscosity or solid polyfunctional isocyanate derived from the reaction of aniline and formaldehyde and having a functionality of 2 or greater, preferably between 2 and 3. The prepolymers are cured to elastomers by adding to the prepolymer at least one curing agent comprising a material containing two or more active hydrogen groups. Such curing agents include the curing agent of U.S. Pat. No. 3,362,921 and in addition, a glycol, glycerol, polyglycol, or polyalkylene glycol mono- or di-ester of a hydroxy carboxylic acid having at least 12 carbon atoms. Certain amines are useful in curing the prepolymers and include primary and secondary aliphatic, cyclic, aromatic, aralkyl and alkaryl diamines.
In U.S. Pat. No. 3,962,094 to Davis, a hollow fiber separatory device useful for dialysis, ultra-filtration, reverse osmosis, hemodialysis, etc., is provided. This device consists of a plurality of fine, hollow fibers whose end portions are potted in a tube sheet and whose open fiber ends terminate in a tube sheet face which provides liquid access to the interior of the fibers. The tube sheet comprises a cured polyurethane consisting essentially of a prepolymer based on the reaction product of castor oil with at least one mole per castor oil hydroxy group of an organic diisocyanate and crosslinked with either castor oil or an ester of a polyhydric alcohol having a hydroxyl functionality of 4 or more and an organic acid containing at least 12 carbon atoms and one or more hydroxy and/or epoxy groups per molecule, or mixtures of castor oil and the such esters.
Patents representative of the art of hollow fiber separatory devices include U.S. Pat. Nos. 2,972,349; 3,228,876; 3,228,877; 3,339,341; 3,442,088; 3,423,491; 3,503,515; and 3,551,331: the disclosures of which are incorporated herein by reference.
The sealing collar is typically derived from a resin which is capable of encapsulating the fibers to provide a seal which prevents the fluid inside the hollow fibers from mixing with the fluid outside the fibers.
A preferred class of resins useful for preparing the sealing collars are flexible polyurethane forming systems as illustrated by U.S. Pat. Nos. 3,362,921; 3,708,071; 3,722,695; 3,962,094; 4,031,012; 4,256,617; 4,284,506; 4,332,927 and Re. 31,389. Centrifugal casting, as illustrated by U.S. Pat. No. 3,492,698, is a representative method employed for preparing sealing collars. In accordance with such a technique, a holding device containing a bundle of fibers arranged in a parallel configuration is placed into a centrifugal-like device which incorporates a potting material reservoir with tubes connecting it to end-molds. An appropriate resin is placed into the potting reservoir and maintained at an appropriate temperature. The entire assembly is then rotated to force the resin down the connecting tubes by the centrifugal force. The resin thereby flows around and among the fibers in the end-molds. The rotation is continued until the resin gels. When polyurethanes are employed as the resin, typical residence time in the centrifuge can vary from about 1 to about 2 hours at room temperature. When rotation is completed the resin impregnated fiber bundle is removed and post-cured. The end molds are then removed and the fiber ends are opened by cutting through the resin collar perpendicular to the fiber bundle.
Other sealing collar forming techniques rely on the force of gravity to force the resin into a mold containing the ends of the hollow fibers. The resin is allowed to gel and then is post-cured.
Regardless of the particular method employed for preparing the sealing collar, the polyurethanes typically employed therein exhibit extended gel and demold times.
In addition to hollow fiber separatory devices, folded membrane separatory devices have also been used in chemical separations such as dialysis, osmotic processes and hemodialysis. In a folded membrane artificial kidney, for example, a membrane sheet is multiply-folded or pleated to form a series of adjacent channels, each channel located between opposed faces of each fold. The edges of the folds in the membrane are sealed together by potting the edges in a sealant. The membrane is then placed in a case usually comprised of polystrene, a styrene-acrylonitrile copolymer or a polycarbonate polymer wherein the chemical separation takes place. In the case of dialysis, the dialysis solution is placed on one side of the membrane and blood is placed on the other side. Polyepoxides and polyurethanes have generally been used to seal the edges of the folded membranes. U.S. Pat. No. 4,267,044 provides a thixotropic polyurethane composition which is particularly useful for sealing such folded membrane devices.
The polyurethane systems of the prior art which have been used to pot the ends of hollow fiber or folded membrane separatory devices have various limitations. For example, the fibers have to be dried prior to potting, otherwise, residual moisture will cause bubbling in the composition when contacting the polyurethane mixtures prior to cure. The drying process is costly and in some cases is not possible, for example, with fibers requiring a large amount of glycerine to sustain pore openings. In addition to the significant amount of moisture or water which exists in these devices, glycerine, which interferes with the reaction between isocyanates and polyols, is also present. The polyurethane systems of the prior art are not suitable for fibers containing great amount of moisture or glycerine. The present invention provides compositions which overcome these problems by utilizing specific hydroxyl bearing compounds and isocyanate compounds which accelerate the reaction of the composition, thus preventing bubble formation.
SUMMARY OF THE INVENTION
The invention relates to biomedical devices of hollow fiber or membrane construction, the ends of which are potted with a polyurethane composition of the reaction product of a liquid ester of a carboxylic acid having at least 8 carbon atoms and an equivalent weight of 275 or less, preferably less than 200, with a polyisocyanate compound. In an alternate embodiment, the polyurethane composition includes the reaction product of a polyether compound having at least 2 hydroxyl groups and an equivalent weight of 185 or less with a polyisocyanate compound. Mixtures of these hydroxyl bearing components may be used to form additional compositions, provided that the equivalent weights of each component in the polyol mixture is as stated above. Also, prepolymers of these polyols can be used if desired.
The invention also relates to methods for sealing the ends of hollow fiber or folded membrane separatory devices with the previously described compositions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The polyols which may be used according to this invention include esters of carboxylic acids having at least 8 carbon atoms, such esters being liquid at ambient temperature and having a hydroxyl functionality of at least 2. To obtain desirable esters, the carboxylic acid generally contains less than about 25 carbon atoms and preferably between 12 and 20. Hydroxyl functionality as used herein is the average number of hydroxyl groups per molecule of ester compound. As noted above, a specific equivalent weight of the overall polyol component is necessary to achieve the desired results of the invention.
These hydroxyl bearing components include esters of ricinoleic acid with polyhydric alcohols, which form a polyricinoleate compound or a combination of polyricinoleate compounds having a hydroxy functionality of 2 or more and an equivalent weight of between about 60 and 275. Such compounds include various di, tri, and tetraricinoleate compounds alone, mixed together, or combined with other polyols provided that the equivalent weight of the mixture or combination is maintained within the range stated above.
These esters are preferably ricinoleic acid polyol esters and more preferably castor oil. Castor oil is a naturally occurring trigylceride of ricinoleic acid. Castor oil is actually a mixture of mono-, di-, and triglyercides and has an average hydroxyl functionality of 2.7. Other ricinoleic acid polyol esters include glycol, polyglycol and other polyhydric alcohol mono-, di-, and polyesters of ricinoleic acid. These ricinoleic acid polyol esters can be made by methods well known in the art, e.g., by direct esterification of ricinoleic acid with alcohols such as ethylene glycol, glycerine, propylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, hexamethylene glycol, polyethylene and polypropylene glycols, sucrose or sorbitol.
Specific ricinoleate ester compounds include ethylene glycol mono-, di- ricinoleates, propyl mono- and di- ricinoleates, penta erythritol mono-, di-, tri-, tetra- and penta- ricinoleates, glycerol ricinoleate, 1,4-cyclohexane dimethanol mono- and di- ricinoleates, butane diol diricinoleate, neopentyl glycol mono- and di- ricinoleates, and mono- or di- ricinoleates of N,N-bis (2-hydroxy propyl) aniline or N,N,N, 1 N 1 - tetrakis (2-hydroxy propyl) ethylene diamine.
A second group of hydroxyl bearing components which are suitable in the compositions of this invention include one or more polyether polyols having a functionality of at least 2 and an equivalent weight between about 30 and 185.
The preferred polyether polyols are polyether triols, and more particularly polyoxypropylene triols. Generally, these polyether triols are prepared by condensing a large excess of an alkylene oxide, such as ethylene oxide or propylene oxide with a glycol, as is well known in the art. The glycol can be a diol such as alkylene glycols, e.g., ethylene glycol or propylene glycol, a triol such as glycerine, a tetrol such as pentaerythritol, etc. Particularly preferred polyols for this invention comprise polyoxypropylene triols, having an equivalent weight of between about 30 and 185.
The organic polyisocyanates which are suitable for this invention include any diisocyanate or polyisocyanate compound. These compounds are well known in the prior art.
Diisocyanates which may be used in this invention include: the arylene diisocyanates, represented by the diisocyanates of the benzene and napthalene series, or mixtures of these compounds. Illustrative of such arylene diisocyanates include: toluene diisocyanate (2,4/2,6); toluene 2,4- diisocyanate; toluene 2, 6-diisocyanate; m-phenylene diisocyanate, xenylene 4,4-diisocyanate; napthalene 1,5 diisocyanate; 3,3-bitolylene 4,4-diisocyanate; diphenylene methane 4,4'-diisocyanate (MDI); 4-chlorophenylene 2,4-diisocyanate; dianisidine diisocyanate, diphenylene ether 4,4'-diisocyanate, and polymeric isocyanates such as polymethylene polyphenylene isocyanate. Other arylene diisocyanates which are useful include lower alkyl and alkoxy-substituted derivatives. Aliphatic and cycloaliphatic diisocyanates, such as isophrone diisocyanate (IPDI), can be employed. Mixtures of arylene and aliphatic or cycloaliphatic diisocyanates can be used in the compositions of this invention. Isocyanate adducts such as modified MDI, trimers, TMP-TDI adducts and biurets of hexamethylene diisocyanate can also be used, if desired.
The amount of organic polyisocyanate to be reacted with the polyol should be sufficient to provide between one and 1.4 mole, preferably between about 1 and 1.1 mole, of diisocyanate per hydroxy group of polyol. For prepolymer formation, an NCO/OH ratio of above about 2:1 and preferably about 3:1 and up to about 7:1 or more is desirable. The most preferred range is between about 4:1 and 5:1 to insure the formation of an isocyanate-terminated prepolymer which is capable of further reaction with the hydroxyl bearing component.
Generally, the polyurethanes based on the above-described polyricinoleate compounds or mixtures provide a minimum hardness of about 50 shore D after reaction with the organic isocyanate compound. Similarly, the polyurethanes based on the previously described polyether polyols provide a hardness of at least 80 shore D after reaction with the isocyanate compound.
EXAMPLES
The scope of the invention is further described in connection with the following examples which are set forth for the sole purpose of illustrating the preferred embodiments of the invention and which are not to be construed as limiting the scope of the invention in any manner. In these examples, all parts given are be weight unless otherwise specified.
EXAMPLE 1
A prepolymer was prepared as follows:
411 of castor oil was added to 189 of toluene diisocyanate (TDI) gradually at a temperature of 35° C. After addition, the temperature was raised up to 60°-70° C. to complete the reaction.
The resulted prepolymer was diluted with 40% of Desmodur W, a hydrogenated MDI. The final product had viscosity of about 3000 cps at 25° C., an NCO % of 16.8, and free TDI content of 0.8%.
100 g of this prepolymer was mixed with 175 g of an ester of pentaerythritol of ricinoleic acid and 0.2% of a dioctyl tin ricinoleate catalyst. The mixture was quickly degassed and then used as a potting compound.
A hollow fiber biomedical separatory device having hollow fibers containing large amounts of glycerin was potted with this polyurethane composition. Potting is accomplished by a centrifugal casting technique as described in U.S. Pat. Nos. 3,228,876 and 3,962,094. The potted area was cut into slices at right angles to reveal the open ends of the fiber tubes. These slices were then immersed into water for 1 minute. The appearance of the slice was then examined by microscope for contact of the potting compound to the hollow fibers and for retention of the fiber geometry. No whitening of the composition due to the absorption of water was found. Furthermore, the polyurethane of this example provided excellent fiber contact and geometry retention without significant volume or strength changes.
EXAMPLES 2-7
Various polyol blends of the ricinoleates listed in the table below were prepared as in Example 1, except that the isocyanate compound utilized was tetra methyl xylene diisocyanate (TMXDI) and that prepolymers were not formed. These compositions were used to pot the separatory device as described in Example 1. The water immersion test results are listed in the following chart:
______________________________________Weight PercentageExample 2 3 4 5 6 7______________________________________PEMDR.sup.1 72 63 58 80 73 82castor oil 28 37 42BDDR.sup.2 20 271,4 CHDMDR.sup.3 18Equivalent 198 209 216 181 198 189WeightHardness, 60 50 45 55 50 65Shore DWater Immersion P B F P B PTest Result______________________________________ Notes .sup.1 penta erythritol monoricinoleate .sup.2 butane diol diricinoleate .sup.3 1,4-cyclohexane dimethanol diricinoleate B = borderline F = failed P = pass
For each formulation 0.1% of dioctyl tin diricinoleate catalyst was utilized.
Thus, to pass the water immersion test, it is seen that the ricinoleate blends should preferably have an equivalent weight of less than about 200 and a hardness of higher than about 50 Shore D depending upon the ricinoleate used. This hardness range is established based on the use of a single diisocyanate, TMXDI. Other isocyanates may provide better performance so that higher equivalent weight ricinoleate blends (i.e., up to 275) can be used, as shown below.
EXAMPLES 8-14
Various polyol blends of ricinoleates were mixed with the isocyanate, Desmodur W, and used to pot the separatory devices as described in Example 1. The water immersion test results were listed in the following table:
______________________________________Weight PercentageExample 8 9 10 11 12 13 14______________________________________PEMDR 36 26 52 41 32 39 32castor oil 64 74BDDR 48 59 681,4 CHDMDR 61 68EquivalentWeight 251 271 228 247 266 255 271Hardness,Shore D 60 55 60 50 28 55 35Water ImmersionTest Result P B P B F P B______________________________________
For each example, the appropriate amount of catalyst was utilized. To pass the water immersion test, it is seen that the ricinoleate polyol blends should show an equivalent weight of less than about 275. Also, the hardness of these compositions should be above 50 Shore D and preferably about 55 to 60, depending upon the specific ricinoleate and polyisocyanate compounds used.
EXAMPLES 15-18
A diphenyl methane diisocyanate based prepolymer, (Vorite 689 from CasChem, Inc.) was mixed with various polyol blends including certain polypropylene glycols (PPG) or ricinoleate compounds, and then used to pot the separatory devices as described in Example 1. The results of water immersion testing for these compounds are listed below:
______________________________________Weight PercentageExample 15 16 17 18______________________________________Lupranol 3300.sup.5 -- -- 73 65Lupranol 2030.sup.6 -- -- 27 35PEMDR 25 17.6 -- --castor oil 75 82.4 -- --catalyst None None DTD.sup.4 DTD.sup.4equivalent weight 273 296 182 200hardness (Shore D) 65 60 80 75Water ImmersionTest P B P F______________________________________ Notes .sup.4 dioctyl tin diricinoleate .sup.5 polyoxypropylene triol eq. wt. 140 .sup.6 polyoxypropylene triol eq. wt. 1000
As shown in the examples, not all compositions passed the water immersion test, and certain ranges of equivalent weight of polyol blends and the hardness of polyurethane system are required for each combination.
With ricinoleates, the equivalent weight should be less than about 275 and preferably less than 200, with a hardness higher than about 50 Shore D to provide a polyurethane system which will pass the water immersion test. With polypropylene glycols, the required equivalent weight should be less than about 185 and hardness should be higher than about 80 Shore D.
While it is apparent that the invention herein disclosed is well calculated to fulfill the objects above stated, it will be appreciated that numerous modifications and embodiments may be devised by those skilled in the art, and it is intended that the appended claims cover all such modifications and embodiments as fall within the true spirit and scope of the present invention. | Polyurethane compositions comprising isocyanate cured specific equivalent weight hydroxyl bearing components used as potting compounds or sealants for hollow fiber or folded membrane biomedical separatory devices, especially when such devices contain containments such as glycerine or water. | 1 |
BACKGROUND OF INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to a collection arrangement for a trash container involving a ramp to provide easy sweeping of trash and debris into the container.
[0003] 2. Background
[0004] Putting trash into containers is always an interesting challenge, and it is often more difficult by the use of standard sized plastic bags to hold and dispose of the trash. The trash location often further complicates the situation. Using such containers indoors usually involves the use of a dustpan and broom and further multiple dumping of the dustpan. When the trash is outside or in the garage, large containers are employed and the sweeping of leaves, dust and other debris often involves shovels and creating much lifting, even if a leaf rake is utilized.
[0005] The subject invention is design to make the collection of trash and debris, whether inside or outside, more easily accomplished by providing a sweeping ramp into the container that is laid on a relatively flat side. For further convenience containers are employed that utilize standard sized disposable plastic bags. In an alternate configuration only the sweeping ramp is employed and is designed to fit various sizes and shapes of existing containers.
[0006] Related United States patents include:
No. Inventor Year 4,802,258 Jensen 1989 5,065,891 Casey 1991 5,803,300 DeMars 1998
Referring to the above list, Jensen discloses a dustpan and guide with elaborate handle with matching flange design that serves as an attaching device and allows sweeping of debris into a conventional round trash container positioned horizontal. No mention of trash bags is made.
[0008] Casey discloses a complicated inner ring that holds trash receptacle liners in such a manner that trapped air toward the bottom of the receptacle is vented allowing the liner to fill more thoroughly.
[0009] DeMars discloses a moving mounting ring that holds a replaceable bag into a trash container in a manner that allows easy bag replacement.
SUMMARY OF INVENTION
[0010] The objectives of the present invention include overcoming the above-mentioned deficiencies in the prior art and providing a potentially economically efficient trash collection arrangement for multiple use involving a sweeping ramp leading to a disposable, contained bag.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows an expanded view of a double wedge ring arrangement for attachment of the sweeping ramp to bag and container.
[0012] FIG. 2 shows the assembled parts from FIG. 1 .
[0013] FIG. 3 shows a cross section of the double wedge ring attachment.
[0014] FIG. 4 shows an expandable sweeping ramp utilizing a spring-loaded attachment mechanism to a trash container.
[0015] FIG. 5 shows an expandable sweeping ramp utilizing ramp side mounting spring clips.
[0016] FIG. 6 shows an expandable sweeping ramp utilizing a pawl and ratchet mechanism.
DETAILED DESCRIPTION OF INVENTION
[0017] A collecting arrangement for a trash container is shown in four configurations in FIGS. 1-6 . FIG. 1 shows an arrangement where a specially designed container is employed. The trash container 10 has a substantially flat side 11 , conveniently obtained by employing a substantially semicircular container 10 , and is stable either upright or lying on the flat side 11 . Additionally the container 10 is sized for a standard replaceable trash bag, and potentially contains recessed handles 14 especially for larger sizes. The trash container 10 , often made of plastic, may contain more than one flat side for many common such containers are routinely made in substantially square or rectangular shapes. Further it is convenient to place a pair of wheels on the outside bottom of said container particular for larger sizes, not shown in FIG. 1 . The standard bag size varies from small sizes of 4 and 13 gallons that are common for house use to larger sizes of 20 through 39 gallons that are normally used for garages and outdoors; however, other sizes that become commonly available are also usable.
[0018] The preferred means for attaching the bag to the container is shown in FIGS. 1-3 . FIG. 1 shows an exploded view of the double wedge rings employed for such attachment, but the bag is not shown. The wedging is tight enough to hold the rings together but not so tight that they cannot be assembled and detached by hand. Ring 20 is wedged into ring 30 , which contains the sweeping ramp 31 , and such arrangement is shown in cross section in FIG. 3 , which also shows the bag 12 attachment via ring 20 to ring 30 . Thus the bag 12 is not attached to the container 10 allowing it to be removed along with the rings and utilized outside of said container for sweeping, especially with small container sizes. The sweeping ramp 31 composed of firm material 32 sized to fit into the top of said container is part of ring 30 . Firm material 32 is identified as a good sweeping base in contrast to flimsy or excessively wavy material where sweeping is difficult. Multiple hasps 13 attach ring 30 to container 10 . Often spring metal blades attached to the edges of the ramp 31 and extending over the trash container 10 edges are utilized; however, these are not shown in FIGS. 1-3 but are shown in FIG. 5 for a different configuration. The handle 33 as shown in FIGS. 1-3 is convenient in the shown location for smaller sizes of the trash container 10 ; however, for larger sizes such a handle is often placed on an edge of the ramp 31 , but this is not shown in FIGS. 1-2 .
[0019] An alternate collecting arrangement is shown in FIGS. 4-6 involving only the ramp part of the arrangement, for the container and its bag are separate as the ramp is designed to fit a number of sizes of containers; yet for completeness, the container and bag are shown in the figures. The container 40 surrounds a standard replaceable trash bag 50 that folds over the container top. A sweeping ramp 41 is composed of firm material 42 . The ramp 41 is adjustable so as to fit into a variety of different sizes of trash containers 40 by means of altering the ramp 41 in width by overlapping material sections 43 , which slide in or out so as to fit a number of sizes of standard trash containers 40 and yet allow an easily employed sweeping ramp 41 . The mounting of the ramp 41 into the trash container 40 opening is shown in three potential manners in FIGS. 4-6 . In FIG. 4 expandable bars 44 loaded with a spiral spring 47 are attached to the underside of the ramp 41 and are positioned to tightly fit against the inner side of said container 40 opening including the bag 50 . Alternatively in FIG. 5 spring clips 45 are mounted 46 on the ramp 41 edges that press tightly against the outer side of the container 40 including the bag 50 , and are convenient to hold the bag 50 into said container 40 . In FIG. 6 one or more pawl and racket mechanisms 60 are employed on the top underside of said ramp 41 that hold the expanded ramp tightly as they contact the inner side of said container 40 opening including the bag 50 .
[0020] A collecting arrangement for a trash container comprising a container for trash with a bag and with a side substantially flat so that said container is stable either upright or lying on the flat side, wherein the container is sized for a standard replaceable trash bag. The trash container, often made of plastic, may contain more than one flat side for many common such containers are routinely made in substantially square or rectangular shapes. Often a convenient shape is semicircular for the trash container. Further it is convenient to place a pair of wheels on the outside bottom of said container particular for larger sizes. The standard bag size varies from small sizes of 4 and 13 gallons that are common for house use to larger sizes of 20 through 39 gallons that are normally used for garages and outdoors.
[0021] A means for attaching the bag to the container so that trash fills the bag further comprises being selected from the group consisting of Velco straps, elastic bands, a series of clips, a wedged insert rings into the inside top of the container, and a hold-down connection. These are standard ways of keeping the bag within the container. The preferred method is the use of a wedged insert double ring which allows the bag to be attached between the rings so that all can be removed together along with the connected ramp and utilized outside of the container for sweeping especially with small container sizes.
[0022] A sweeping ramp composed of firm material is sized to fit into the top of the container along with means for attaching the ramp to the trash container, while lying on the flat side, so that trash swept onto and over the ramp flows into the bag. It is understood that referring to a sweeping ramp implies the use of a piece of hand-operated equipment, such as a broom, brush, or a leaf rake, that is not specifically identified herein. Firm material is identified as a good sweeping base in contrast to flimsy or excessively wavy material where sweeping is difficult. A number of common ways of attaching the ramp and container further comprise being selected from the group consisting of an insert ring sized to the top of said container employing multiple hasps, a handle attached to the side of said ramp, one or more spring metal blades attached to the edges of said ramp and extending over said trash container edges, and combinations thereof. The preferred method of an insert ring with connecting multiple hasps matches with the previous bag holding insert ring to allow the bag and ramp to move together. When a handle is employed it can be screwed into the ramp and utilized either by hand or by foot, the latter is particularly convenient when outdoors. When spring metal blades are employed, they conveniently hold the ramp to the container as well as the bag in place.
[0023] A collecting arrangement for a trash container, which surrounds a standard replaceable trash bag that normally folds over the container top, comprising a sweeping ramp composed of firm material with means for adjusting the ramp in width so as to fit into a variety of different sizes of trash containers, and means for mounting the ramp into said trash container opening, wherein the trash container is positioned on a side on a substantially flat plane so that the rear of the ramp significantly contacts a the plane, often a floor inside or the ground outside, allowing sweeping of the trash onto and over the ramp and into the trash bag within the container.
[0024] The means for adjusting said ramp in width further comprises construction with overlapping sliding material sections. These sections can slide in or out so as to fit a number of sizes of standard trash containers and yet allow an easily employed sweeping ramp.
[0025] The means for mounting the ramp into the trash container opening further comprises a number of potential methods. Spring-loaded expandable bars are attached to the underside of the upper ramp and are positioned to tightly fit against the inner side of the container opening including the bag, and these are conveniently blocked from completely coming apart. Alternatively spring clips are mounted on the upper ramp edges that press tightly against the outer side of the container including the bag, and are convenient to hold the bag into the container. A further method uses one or more pawl and racket mechanisms on the upper underside of the ramp that hold the expanded ramp tightly as they contact the sides of the container opening including the bag. Lifting the pawl allows the ramp to slide for removal.
[0026] The foregoing description of the specific embodiments will so fully reveal the general nature of the invention 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 or modifications 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 herein is for the purpose of description and not of limitation. | The present invention provides an economically efficient trash collection arrangement for multiple use involving a sweeping ramp leading to a disposable, contained bag. In one configuration a special shaped container is provided as part of the arrangement, while in a further model the sweeping ramp is employed with a wide range of available containers. | 1 |
STATEMENT
[0001] The work leading to this disclosure received financing from the European Union as part of Framework Programme 7 (FP7/2007-2013) under project number 241718 EUROBIOREF.
TECHNICAL FIELD
[0002] Embodiments of the disclosure are directed to a process for synthesizing esters of C11 and C12 ω-aminoalkanoic acids, comprises a step of metathesis, using esters of C10 and C11 ω-alkenenoic acids as starting material.
BACKGROUND SUMMARY
[0003] The polyamides industry uses a whole range of monomers consisting of long-chain ω-amino acids, commonly termed Nylon, which are characterized by the length of methylene chain (—CH 2 ) n separating two amide functions CO—NH—. Known, accordingly, are nylon 6, nylon 6-6, nylon 6-10, nylon 7, nylon 8, nylon 9, nylon 11, and nylon 13, etc. The “higher” nylons 11 and 13, for example, which use ω-amino acids as monomer, occupy a separate place in this class, insofar as they are synthesized not from petroleum-derived products (C2 to C4 olefins, cycloalkanes or benzene), but from fatty acids/esters which are present in natural oils.
[0004] One example of a process using a fatty acid as starting material is that of the preparation of fatty nitriles and/or amines from fatty acids extracted from plant or animal oils. This process is described in the Kirk-Othmer encyclopedia, vol. 2, 4th edition, page 411. The fatty amine is obtained in a number of steps. The first step involves methanolysis or hydrolysis of a plant oil or of an animal fat, producing, respectively, the methyl ester of a fatty acid, or a fatty acid. The methyl ester of the fatty acid may subsequently be hydrolyzed to form the fatty acid. The fatty acid is subsequently converted into nitrile by reaction with ammonia, and finally into amine by hydrogenation of the resultant nitrile.
[0005] Within the field of chemistry, moreover, present environmental developments are resulting in preference being given to the exploitation of natural raw materials originating from a renewable source. It is for this reason that certain research and development studies have been taken up for the purpose of industrial development of processes using fatty acids/esters as starting material for preparation of these ω-amino acid monomers.
[0006] The main studies have looked at the synthesis of 9-amino nonanoic acid, the precursor to Nylon 9, from oleic acid of natural origin. With regard to this monomer, it is possible to cite the work “n-Nylons, Their Synthesis, Structure and Properties”—1997, published by J. Wiley and Sons, in which section 2.9 (pages 381 to 389) is devoted to 9-Nylon.
[0007] Industrially, for the preparation of polyamide polymerization monomers, there are only few examples of processes using natural oils as starting material. One of the rare examples of an industrial process using a fatty acid as starting material is the preparation process, from the methyl ester of ricinoleic acid, extracted from castor oil, of 11-amino undecanoic acid, which forms the basis for the synthesis of Rilsan 11®. This process is described in the work “Les Procédés de Pétrochimie” by A. Chauvel et al., published by Editions TECHNIP (1986). The 11-amino undecanoic acid is obtained in a number of steps. The first involves a methanolysis of the castor oil in a basic medium, producing methyl ricinoleate, which is subsequently subjected to pyrolysis to give heptanaldehyde on the one hand and methyl undecylenate on the other. The latter is converted into acid form by hydrolysis. The acid formed is subsequently subjected to hydrobromination, to give the ω-brominated acid, which is converted by ammonolysis into 11-amino undecanoic acid.
[0008] The applicant has since continued work on the processes for synthesis of these higher monomers, based on the use of natural oils which are sources of oleic, ricinoleic, lesquerolic, erucic or other acids. The applicant, accordingly, has explored a pathway wherein the acid function was converted during the process into nitrile function by nitrilation (ammonization) and then, after introduction of an acid or ester function into the molecule, by oxidative cleavage or metathesis with an acrylate, was reduced to primary amine function at the end of the conversions. This is the context in which the applicant filed a patent application, WO2010/055273, covering different versions of implementation of the process, all of them involving the formation of an ω-unsaturated fatty nitrile.
SUMMARY OF THE DISCLOSURE
[0009] In the process of embodiments of the disclosure, one step is the nitrilation of the acid/ester function of the unsaturated fatty acid.
[0010] The reaction scheme for the synthesis of nitriles from a fatty acid may be summarized as follows.
[0000]
[0011] There are two types of processes based on this reaction scheme: a (generally batch) process in liquid phase, and a (generally continuous) process in vapor phase.
[0012] In the batch process (liquid phase), the fatty acid or a mixture of fatty acids is charged with a catalyst, which is generally a metal oxide and usually zinc oxide. The reaction mixture is brought to approximately 150° C. with stirring, and then the introduction of gaseous ammonia is commenced. In a first phase, an ammonium salt or ammonium soap is formed. The temperature of the reaction mixture is then brought to around 250°-300° C., still with introduction of ammonia. The ammonium salt undergoes conversion to amide, with release of a first molecule of water. Then, in a second phase and with the aid of the catalyst, the amide undergoes conversion into nitrile, with formation of a second molecule of water. This water formed is removed continuously from the reactor, carrying with it the unreacted ammonia and a small amount of the lighter fatty chains.
[0013] In the (continuous) gas-phase process, the charge is evaporated and brought into contact with ammonia which is at a temperature of between 250 and 600° C., in the presence of a catalyst. This catalyst is generally selected from the class of metal oxides consisting of the oxides of metals, taken alone or as a mixture, such as Zr, Ta, Ga, In, Sc, Nb, Hf, Fe, Zn, Sn or alumina, silica, a thorium oxide, and particularly doped alumina.
[0014] These reactions, in their various forms, are mentioned in the Ullmann encyclopedia, vol. A2, page 20, and the Kirk Othmer encyclopedia, vol. 2, pages 411-412, and have been a subject of numerous patents, filed in particular by the company KAO. These include U.S. Pat. Nos. 6,005,134, 6,080,891, and 7,259,274, which describe the synthesis of aliphatic nitriles in liquid phase from fatty acids in the presence of a titanium catalyst. For the same applicant and for the same type of process, there are Japanese applications 11-117990 (26 Apr. 1999) with a niobium catalyst, and 9-4965 (14 Jan. 1997) with a zirconium catalyst. There is also a U.S. Pat. No. 4,801,730, which describes the nitrilation of glycerides in liquid phase, and a Japanese application in the name of Lion Corp, of 13 Mar. 1991 (publication No. JP 4283549), which is directed to the synthesis of nitrile in gaseous phase.
[0015] In the studies it has conducted, the applicant has observed that the nitrilation step played an important part, particularly in view of the fact that it was carried out on an ω-unsaturated acid. The reason is that the location of the double bond at the chain end, and therefore with little protection, is able to give rise to formation of isomers, owing to the shifting of the double bond. Having observed these phenomena, the applicant noted that this drawback could be largely limited by working with the ester rather than with the corresponding acid, which would allow operation under “milder” conditions. The reason is that, since the boiling point of the ester was lower than that of the corresponding acid, it was possible to obtain stronger vapor tensions with the ester. Moreover, by working in a reactor operating continuously either in gas phase or in mixed liquid-gas phase, the residence time of the reactants in contact with the catalysts was significantly less than in conventional (batch) liquid phase, allowing isomerization during the process to be limited.
[0016] The known art essentially describes the liquid-phase nitrilation of the acid, and those which talk of gas phase ignore the problem of the isomerization of the terminal double bonds, their objectives being greatly different from those of the process of embodiments of the disclosure.
[0017] The process of embodiments of the disclosure aims to overcome the drawbacks of the known art.
DETAILED DESCRIPTION
[0018] Embodiments of the disclosure provide a process for synthesizing acids or esters of ω-aminoalkanoic acids comprising 11 or 12 carbon atoms from ω-unsaturated acid or ester comprising respectively 10 or 11 carbon atoms, characterized in that it comprises three main steps:
1) nitrilation of the ω-unsaturated acid/ester of the charge, of formula CH 2 ═CH—(CH 2 ) n —COOR, in which n is 7 or 8 and R is either H or an alkyl radical comprising 1 to 4 carbon atoms, by action of ammonia, in a reactor operating continuously in gas phase or in mixed gas-liquid phase, in the presence of a solid catalyst, then 2) conversion of the resulting nitrile of formula CH 2 ═CH—(CH 2 ) n —CN by metathesis with an acrylate of formula CH 2 ═CH—COOR 1 , where R 1 is either H or an alkyl radical comprising 1 to 4 carbon atoms, and lastly 3) hydrogenative reduction of the nitrile function of the compound of formula R 1 OOC—CH═CH—(CH 2 ) n —CN to give an amino acid or an amino ester of formula R 1 OOC—(CH 2 ) n+2 —CH 2 NH 2 .
[0022] The nitrilation step is carried out in a reactor operating continuously, in other words in which the reactants, whether gaseous or liquid in origin, are introduced (and the products are extracted) into (and from) the reactor continuously in accordance with predetermined flow rates.
[0023] In a first embodiment, the two reactants may be introduced into the reactor in the gaseous state (pure gaseous phase).
[0024] In the other embodiment (mixed phase), the ammonia is introduced in the form of gas while the ester (acid) is introduced, after optional preheating, into the reactor close to the catalyst bed, at least partly in liquid form at a rate determined so as to flow in the form of a film (trickle bed) over the heated catalyst bed, in contact with which a fraction of the liquid is evaporated. The reaction, or reaction series, takes place on contact with the surface of the catalyst, or in its immediate proximity. This “trickle bed” technique is well-known and widely employed in the petroleum industry. The flow of ammonia may be cocurrent or counter-current to the flow of ester.
[0025] The process of embodiments of the disclosure use as its charge ω-unsaturated acids or esters comprising either 10 atoms or 11 atoms of carbon per molecule. The first—particularly methyl 9-decenoate—are sold in ester form by ELEVANCE Renewable Sciences; the second—particularly methyl 10-undecenoate—are produced by the company ARKEMA in its aforementioned castor oil-based process, with the methyl undecylenate being obtained after pyrolysis.
[0026] The acrylate used in the second step will be selected from acrylic acid, methyl acrylate, ethyl acrylate, n-propyl or isopropyl acrylate, or n-butyl, isobutyl, sec-butyl or tert-butyl acrylate.
[0027] The reaction scheme for the process is as follows:
[0000] CH 2 ═CH—(CH 2 ) n —COOR+NH 3 CH 2 ═CH—(CH 2 ) n —CN+ROH+H 2 O
[0000] CH 2 ═CH—(CH 2 ) n —CN+CH 2 ═CH—COOR 1 R 1 OOC—CH═CH—(CH 2 ) n —CN+CH 2 ═CH 2
[0000] R 1 OOC—CH═CH—(CH 2 ) n —CN+3H 2 R 1 OOC—(CH 2 ) n+2 —CH 2 NH 2 .
Nitrilation Step
[0028] The process of catalytic nitrilation of fatty acids is carried out at a reaction temperature of generally between 200 and 400° C. and preferably between 250 and 350° C. The ω-unsaturated fatty acids/esters charge is evaporated and brought to a temperature of between 180 and 350° C. in contact with ammonia introduced at a temperature of between 150 and 600° C.
[0029] The pressure is between 0.1 and 10 atmospheres (absolute) and preferably between 0.5 and 5, and more preferably between 1 and 3 atm.
[0030] When the nitrilation step is carried out in gas phase, the ω-unsaturated ester of fatty acids is evaporated and brought at a temperature of between 180 and 350° C. in contact with ammonia introduced at a temperature of between 150 and 600° C. and under a pressure of between 0.1 and 10 atmospheres (absolute), preferably between 0.5 and 5, and more preferably between 1 and 3 atmospheres, in the presence of solid catalyst; the reaction temperature is preferably between 200° C. and 400° C.
[0031] In the variant embodiment of the process that is entirely in gas phase, the rates at which the reactants are introduced are such that the contact time with the solid catalyst is between 1 second and 300 seconds. In this case, the contact time is determined by the ratio calculated as follows: {volume of catalyst (in liters)×3600}/{[flow rate of unsaturated ester (in moles/h)+flow rate of ammonia (in moles/h)]×22.4}=contact time in seconds.
[0032] In a variant of the process, the step of nitrilation of the ω-unsaturated fatty acid ester is carried out in mixed phase according to the trickle bed technique, the ω-unsaturated ester of fatty acids, optionally preheated, being passed progressively in trickling liquid form over the solid catalyst, which is heated at a temperature such that there is partial, progressive evaporation of the ester, allowing the reactions with ammonia on contact with the surface of the catalyst or in its immediate proximity. The reaction temperature is generally between 200 and 400° C. and preferably between 250 and 350° C. The rate at which the ester is introduced is such that the mean residence time of the liquid phase in the reactor is less than 1 hour, and preferably less than 30 minutes. This contact time is determined by the following calculation: volume of catalyst (in liters)/flow rate of unsaturated ester (in liquid liters at 25° C. per hour), or the inverse of the liquid hourly liquid volume rate.
[0033] In this embodiment, it is possible to work in cocurrent, meaning that the gas current and the liquid flow are descending, or in countercurrent, with the gas flow being ascending and the liquid flow descending. This latter variant is preferred in the process of an embodiment of the disclosure. The countercurrent version, with gas ascending and ester descending, may be of particular advantage for limiting the hydrolysis of the nitrile formed. The reason is that in this configuration, the ammonia is injected at the bottom, and the water and alcohol emerge at the top; the ester enters at the top, and the nitrile emerges at the bottom. At the bottom, therefore, the concentration of nitrile and of ammonia is high, and at the top the concentration of ester, water, and alcohol is high, and the concentration of ammonia is less. It is therefore possible to shift the equilibria, particularly that of the hydrolysis of the nitrile, which restores the acid.
[0034] The molar NH 3 /fatty ester ratio of the reactants is between 1 and 50, preferably between 3 and 30, and more preferably between 5 and 20.
[0035] The reaction is carried out in the presence of a solid catalyst.
[0036] This catalyst is selected from the class of metal oxides or mixed metal oxides, consisting of the oxides of metals, alone or as a mixture, such as Zr, Ce, Ti, Mo, W, V, S, P, Ta, Ga, In, Sc, Nb, Hf, Fe, Zn, Sn, Al, Si. The oxides or mixed oxides constituting the catalyst may be doped with other metals for the purpose of enhancing the catalytic performance levels. The dopants which are suitable for the application include the following: rare earths, La, Pr, Nd, Sm, Eu, Dy, Gd, Ho, Yb, and also Cu, Ni, Fe, Pb, Sn, In, Mn, Co, Mo, W, Nb, Zn, Cr, Si, Mg, Ca, Sr, Sc, Y.
[0037] Preferred catalysts in the process of embodiments of the disclosure are oxides based on zirconium, on cerium, on titanium, on niobium, or on aluminum.
[0038] With zirconium oxide, the dopant used will comprise rare earths, in an amount of 5 to 50 mol %, and preferably from 8% to 15%, but also P, S, Cu, Ni, Fe, Pb, Sn, In, Mn, Mo, W, Nb, Zn, Cr, Si with amount of 1% to 30% and preferably greater than 5%.
[0039] With cerium oxide, the dopant used will preferably be as follows: Mg, Ca, Sr, Sc, Y, and rare earths, with amounts of 1% to 50%, and preferably more than 10%.
[0040] With titanium oxide, the dopant preferred will be W, Mo, P, S, Fe, Nb, Sn, Si, with amounts of 1% to 50% and preferably of 5% to 20%.
[0041] As a method for preparing the catalysts, there are a number of possible candidate methods, including coprecipitation, atomization, mixing, and impregnation. Precursors of the oxides in various forms may be used, particularly in oxide, nitrate, carbonate, chloride, sulfate (including oxysulfate), phosphate, organometallic compound, acetate, and acetylacetonate form. It is also possible to use the salts in sulfate or phosphate form in the preparation of catalysts insofar as S or P are used as dopants of the catalyst. In that case, the preparation of a catalyst from zirconium or titanium oxysulfate leads to a catalyst suitable for the process of embodiments of the disclosure.
[0042] The catalysts have a specific surface area of between 10 and 500 m 2 /g, and preferably of between 40 and 300 m 2 /g.
[0043] The catalysts are formed by techniques which are suitable according to the type of reactor used.
[0044] A number of reactor technologies may be suitable for the process of embodiments of the disclosure: fixed bed reactors, fluidized bed reactors in gas phase.
[0045] For the fixed bed reactors, the catalysts are present in the form of particles with a particle size of 1 to 10 mm, or in the form of porous monoliths. The catalyst may in that case have a variety of forms: beads, cylinders—hollow or not—sticks, etc. The reactor is used either solely in gas phase or else as a trickle bed, where a gas phase coexists with a liquid phase.
[0046] The reactor may be employed as a fluidized bed. In this case, the catalyst is preset in the form of a powder with a diameter of 40 to 500 microns and preferably with an average particle size of 80 to 250 microns. The gas flow rate of NH 3 reactant (majority gas in the reactor) is sufficient to ensure fluidization of the solid. The fatty acids and esters have high boiling points and so it may be advantageous to inject these reactants still in liquid form directly into the fluidized bed of solid, with contact with the hot catalyst ensuring rapid evaporation of the reactants, and also an increase in the gas volume ensuring fluidization. The temperature of the reactor is regulated partly by the entry of liquid and gaseous reactants at a high temperature, and partly by spines for circulation of a heat transfer fluid that are installed actually within the reactor.
Metathesis Step
[0047] Metathesis reactions have been known for a long time, although their industrial applications are relatively limited. With regard to their use in the conversion of fatty acids (esters), reference may be made to the article by J. C. Mol “Catalytic metathesis of unsaturated fatty acid esters and oil” in Topics in Catalysis, vol. 27, Nos. 1-4, February 2004, p. 97 (Plenum Publishing).
[0048] Catalysis of the metathesis reaction has been the subject of a great many studies and the development of sophisticated catalyst systems. Mention may be made, for example, of the tungsten complexes developed by Schrock et al. (J. Am. Chem. Soc. 108 (1986) 2771 or Basset et al. Angew. Chem., Ed. Engl. 31 (1992) 628. Having appeared more recently are catalysts known as Grubbs catalysts (Grubbs et al., Angew. Chem., Ed. Engl. 34 (1995) 2039 and Organic Lett. 1 (1999) 953), which are ruthenium-benzylidene complexes. This is a homogeneous catalysis. Heterogeneous catalysts have also been developed, based on metals such as rhenium, molybdenum, and tungsten that are deposited on alumina or silica.
[0049] Finally, studies have been carried out for the production of immobilized catalysts, these being catalysts whose active principle is that of the homogeneous catalyst, especially the ruthenium-carbene complexes, but is immobilized on an inert support. The objective of three studies is to enhance the selectivity of the cross metathesis reaction with regard to side-reactions, such as the “homo-metatheses” between the reactants when combined. The studies relate not only to the structure of the catalysts but also to the effect of the reaction medium and to the additives that may be introduced. They also relate to the methods of recovering the catalyst after reaction.
[0050] In the process of embodiments of the disclosure, any active and selective metathesis catalyst will be able to be used. Preferably, however, ruthenium-based catalysts will be used.
[0051] The cross metathesis reaction with the acrylate compound is carried out under very well-known conditions. The reaction temperature is between 20 and 100° C., generally at atmospheric pressure, in a stream of inert gas or under partial vacuum, to allow easy release of ethylene in the presence of a ruthenium-based catalyst.
[0052] The ruthenium catalysts are selected preferably from charged or noncharged catalysts of general formula:
[0000] (X1) a (X2) b Ru(carbene C)(L1) c (L2) d
[0000] in which:
a, b, c, and d are integers, with a and b being 0, 1 or 2; c and d being 0, 1, 2, 3, or 4, X1 and X2, which are identical or different, each represent a charged or noncharged unidentate or multidentate ligand; examples include halides, sulfate, carbonate, carboxylates, alkoxides, phenoxides, amides, tosylate, hexafluorophosphate, tetrafluoroborate, bis-triflylamide, tetraphenylborate, and derivatives. X1 or X2 may be bonded to L1 or L2 or to the (carbene C) so as to form a bidentate (or chelate) ligand on the ruthenium, and L1 and L2, which are identical or different, are electron-donating ligands such as phosphine, phosphite, phosphonite, phosphinite, arsine, stilbine, an olefin or an aromatic, a carbonyl compound, an ether, an alcohol, an amine, a pyridine or derivative, an imine, a thioether, or a heterocyclic carbene, L1 or L2 may be bonded to the (carbene C) so as to form a bidentate or chelate ligand, The (carbene C) may be represented by the general formula: C_(R1)_(R2), for which R1 and R2 are identical or different, such as hydrogen or any other saturated or unsaturated cyclic, branched, or linear hydrocarbon group, or aromatic hydrocarbon group. Examples include complexes of ruthenium with alkylidenes, or with cumulenes such as vinylidenes Ru═C═CHR, or with allenylidenes Ru═C═C═CR1R2, or with indenylidenes.
[0059] A functional group which enhances the retention of the ruthenium complex in the ionic liquid may be grafted on at least one of the ligands X1, X2, L1, L2, or on the carbene C. This functional group may be charged or noncharged, such as, preferably, an ester, an ether, a thiol, an acid, an alcohol, an amine, a nitrogen-containing heterocycle, a sulfonate, a carboxylate, a quaternary ammonium, a guanidinium, a quaternary phosphonium, a pyridinium, an imidazolium, a morpholinium, or a sulfonium.
Hydrogenation Step
[0060] The step of synthesizing ω-amino esters or ω-amino fatty acids from unsaturated fatty (acid) nitrile-esters involves a conventional hydrogenation referred to in the Encyclopedias mentioned above, in the same sections and chapters. Hydrogenation of the nitrile function automatically entails saturation of the double bond present in the molecule.
[0061] The reduction of the nitrile function to primary amine is well known to the skilled person. The hydrogenation may be carried out in the presence of precious metals (Pt, Pd, Rh, Ru, etc.) at a temperature of between 20 and 100° C. under a pressure of 1 to 5 bar. It may also be carried out in the presence of catalysts based on iron, nickel, or cobalt, which may entail more severe conditions, with temperatures of the order of 150° C. and with high pressures of several tens of bar. The catalysts are numerous, but preference is given to using Raney nickels and Raney cobalts. In order to promote the formation of primary amine, a partial pressure of ammonia is employed.
[0062] With preference, the step of reducing fatty (acid) nitrile-esters to ω-amino esters or ω-amino fatty acids involves a hydrogenation using any conventional catalyst and preferably Raney nickels and Raney cobalts.
[0063] The charge treated is preferably in the form of ω-unsaturated fatty acid ester.
The Process of Embodiments of the Disclosure is Illustrated by the Examples which Follow, which are Given without Limitation
Example 1
Nitrilation
[0064] The active element of the catalyst that is used is an Anatase ST 31119 titanium oxide produced by the company Saint-Gobain, having a specific surface area of 48 m 2 /g. The titanium oxide is impregnated with an ammonium paratungstate solution to give a homogeneous coating of tungsten oxide of 5% by weight. The solid is subsequently calcined in a stream of air at 400° C. for 2 hours.
[0065] 1 g of catalyst is placed in a tubular reactor with a diameter of 10 mm. Silicon carbide is placed over the catalyst bed, and ensures preheating of the reactants. The reactor is supplied with a gas mixture of ammonia and methyl undecylenate, in a molar ratio of 5/1 and with a HSV of 600 h −1 , or a contact time of approximately 5 seconds. The reactants are preheated very rapidly to 250° C. before entering the reactor. Following reaction, the gases are cooled to approximately 120° C., to allow condensation of the nitrile, and of unconverted reactants, and to keep the ammonia and also the water and methanol produced in the gas phase. The products of the reaction are subsequently analyzed by chromatography.
[0066] The conversion of the methyl undecylenate is 99.5%, and the yield of nitrile is 96%, at a reaction temperature of 300° C. The selectivity for 10-cyanodecene (omega unsaturated nitrile) is 95%, relative to the entirety of the nitriles produced.
Example 2
Comparative
[0067] This example illustrates the conventional liquid-phase nitrilation step converting 10-undecenoic acid into nitrile of formula CN—(CH 2 ) 8 —CH═CH 2 .
[0068] The nitrilation reaction of 10-undecenoic acid (3.5 g) to form the ω-unsaturated nitrile of formula CN—(CH 2 ) 8 —CH═CH 2 is carried out batchwise. The reaction mixture is heated to 160° C. at a rate of 1° C. per minute. Introduction of ammonia (0.417 liter/kg acid·min) commences when the 160° C. have been reached stably, and this temperature is maintained until the acid index of the mixture falls below 0.1 mg KOH/g. The temperature is subsequently increased to 265° C. (the temperature is limited by the very substantial evaporation of the mixture at the operating pressure). The reaction is halted after 18 hours. Through the synthesis, a dephlegmator located downstream of the reactor is maintained at 130° C. The reaction is carried out at atmospheric pressure in the presence of a zinc oxide catalyst (0.0625% by weight relative to the acid). Continuous removal of the water formed entrains the excess ammonia and allows rapid completion of the reaction. 2.6 g of the nitrile are recovered, and are separated by vacuum distillation. The omega unsaturated nitrile represents 90% of the nitriles obtained.
Example 3
Cross Metathesis
[0069] This example illustrates the cross metathesis reaction of undecenenitrile of formula CN—(CH 2 ) 8 —CH═CH 2 with methyl acrylate, with the Hoveyda-Grubbs II catalyst:
[0000]
[0070] A 50 ml Schlenk tube purged with nitrogen is charged with 83 mg of 10-undecenenitrile (0.5 mmol), 86 mg of methyl acrylate (1 mmol) and 10 ml of toluene distilled over sodium benzophenone. 9.5 mg of 2nd-generation Hoveyda-Grubbs catalyst (1.5×10 −2 mmol) are added, and the mixture is heated at 100° C. for 1 hour.
[0071] Analysis by gas chromatography shows that the conversion of 10-undecenitrile is 100% and that the yield of usaturated nitrile-ester is 98%.
Example 4
Hydrogenation
[0072] The reaction mixture obtained from example 3 is then transferred to a 50 ml Parr bomb (filled to 22 ml). 10 mg of 1% Pd/C catalyst and 17 mg of potassium tert-butoxide (0.15 mmol) are added and the bomb is pressurized under 20 bar of hydrogen. Heating is carried out at 80° C. for 48 hours with magnetic stirring.
[0073] Analysis by gas chromatography shows that the conversion of the unsaturated nitrile-ester is 90% and that the yield of methyl 12-amino-dodecanoate is 64%.
Example 5
Comparative
[0074] This example illustrates the step of conventional liquid-phase nitrilation converting the methyl ester of 10-undecenoic acid into nitrile of formula CN—(CH 2 ) 8 —CH═CH 2 .
[0075] The nitrilation reaction of the ester of 10-undecenoic acid (3.77 g) to form the ω-unsaturated nitrile of formula CN—(CH 2 ) 8 —CH═CH 2 is carried out batchwise, and in liquid phase. The procedure is as for example 2. The reaction mixture is heated to 160° C. at a rate of 1° C. per minute. Introduction of ammonia (0.417 liter/kg acid·min) commences when the 160° C. have been reached stably. The acid index remains low since an ester is present. The temperature is subsequently raised to 240° C. (the temperature is limited by the boiling point of the methyl ester). The reaction is carried out with total reflux of the methyl ester and is therefore very difficult to carry out, and energy-consuming. The reaction temperature increases gradually with the conversion of the methyl ester, reaching a plateau due to the boiling of the desired product: 10-undecenenitrile. The reaction is halted after 18 hours. Throughout the synthesis, a dephlegmator located downstream of the reactor is maintained at 130° C. The reaction is carried out at atmospheric pressure in the presence of a zinc oxide catalyst (0.0625% by weight relative to the acid). Continuous removal of the water formed entrains the excess ammonia and allows rapid completion of the reaction. 1.2 g of the nitrile are recovered, and are separated by vacuum distillation. The omega unsaturated nitrile represents 85% of the nitriles obtained.
Example 6
Nitrilation
[0076] Nb 2 O 5 , freshly prepared by hydrolysis of niobium chloride (until chloride is absent from the washing liquors in the silver nitrate test), then calcining at 300° C. in air for 1 hour, is used as catalyst.
[0077] 5 g of catalyst are placed in a tubular reactor with a diameter of 10 mm. Silicon carbide is placed over the catalyst bed, and ensures preheating of the reactants. The reactor is supplied with a gas mixture of ammonia and methyl undecylenate, in a molar ratio of 5/1 and with a HSV of 120 h −1 , or a contact time of approximately 30 seconds. The reactants are preheated very rapidly to 200° C. before entering the reactor. Following reaction, the gases are cooled to approximately 120° C., to allow condensation of the nitrile, and of unconverted reactants, and to keep the ammonia and also the water and methanol produced in the gas phase. The products of the reaction are subsequently analyzed by chromatography.
[0078] The conversion of the methyl undecylenate is 97%, and the yield of nitrile is 95%, at a reaction temperature of 250° C. The selectivity for 10-cyanodecene or 10-undecenenitrile (omega unsaturated nitrile) is 96%, relative to the entirety of the nitriles produced. | A process for the synthesis of C11 and C12 ω-amino-alkanoic acid esters including a step of continuous nitrilation in the gas phase or in a mixed gas-liquid phase, a step of metathesis and a step of reduction by hydrogenation, using, as raw material, C10 and C11 ω-alkenoic acid esters. | 2 |
[0001] This application claims priority from U.S. Provisional Patent Application No. 61/118,451 filed 27 Nov. 2008.
FIELD AND BACKGROUND OF THE INVENTION
[0002] The present invention relates to a method for diagnosing the prognosis of damaged animal tissues, including human tissue by detection of an electric current flow through the tissue. The invention relates to a method and procedure for measuring, recording and analyzing the electrical field in and around areas of a living body and in particular the method identifies and defines a discrete electrical profile of a wound during a healing, worsening or stopped condition.
[0003] Electrophysiology is the science and branch of physiology that delves into the flow of ions in biological tissues, the electrical recording techniques which enable the measurement of this flow and their related potential changes. One system for such a flow of ions is the Power Lab System by ADInstruments headquartered in Sydney, Australia.
[0004] Clinical applications of extracellular recording include among others, the electroencephalogram and the electrocardiogram. To understand these biomedical signals, it is necessary to understand signal types, properties and statistics.
[0005] Deterministic signals are exactly predictable for the time span of interest. Deterministic signals can be described by mathematical models. Stochastic or random signals are those signals whose value has some element of chance associated with it, therefore it cannot be predicted exactly. Consequently, statistical properties and probabilities must be used to describe stochastic signals. In practice, biological signals often have both deterministic and stochastic components.
[0006] Regarding signal amplitude statistics, a number of statistics may be used as a measure of the location or “centre” of a random signal. These include,
The mean, which is the average amplitude of the signal over time. The median, which is the value at which half of the observations in the sample have values smaller than the median and half have values larger than the median. The median is often used as the measure of the “centre” of a signal because it is less sensitive to outliers. The mode, which is the most frequently occurring value of the signal. The maximal and minimal amplitude, which are the maximal and minimal value of the signal during a given time interval. The range or peak-to-peak amplitude, which is the difference between the minimum and maximum values of a signal.
[0012] Regarding continuous time signals versus discrete time signals, signals are continuous time signals when the independent variable is continuous, therefore the signals are defined for a continuum of values of the independent variable X(t). An analogue signal is a continuous time signal. Discrete time signals are only defined at discrete times; the independent variable takes on only a discrete set of values X(n). A digital signal is a discrete time signal.
[0013] A discrete time signal may represent a phenomenon for which the independent variable is inherently discrete (e.g., amount of calories per day on a diet). On the other hand, a discrete signal may represent successive samples of an underlying phenomenon for which the independent variable is continuous (e.g., a visual image captured by a digital camera is made of individual pixels that can assume different colors).
[0014] There are quantitative methods to measure the frequency and amplitude of a waveform. One of the most well known is called spectral analysis: any waveform can be mathematically decomposed in a sum of different waveforms. This is what the so-called Fourier analysis does; it decomposes the waveform in different components and measures the amplitude (power) of each frequency component. What is plotted is a graph of power (amplitude) vs. frequency.
[0015] Whereas research on direct current (DC) activity in wound healing and tissue remodeling has a long history, electric fields of alternating current (AC) with specific frequencies have been much less studied.
[0016] Specific frequencies have been detected in various biological pathways known to be associated with wound healing such as pain, cell metabolism inter-cellular communication and bone growth. However, due to the absence of suitable measurement tools, there has been no definitive proof of involvement of AC with defined frequency spectra in wounds.
[0017] Further, to date no diagnostic method based on a discrete electrical profile that provides a prognosis for wound healing has been ventured in the medical filed.
[0018] There is therefore a need for a diagnostic method that identifies and defines a discrete electrical profile of a wound during a healing, worsening or stopped condition so as to provide a prognosis for such wounds. It would be beneficial if the method is linked to an appropriate electrical pulse transmission device in order to monitor and adjust the electrical therapy applied to damaged tissue based on the measured electrical field of the relevant tissues of the body.
SUMMARY OF THE INVENTION
[0019] The present invention is a diagnostic method that identifies and defines a discrete electrical profile of a wound during a healing, worsening or stopped condition so as to provide a prognosis for such wounds.
[0020] According to the teachings of the present invention there is provided, 1.
[0021] A method of detecting the current state of living human and animal target tissue, the method comprising: (a) detecting and recording an electrical signal in and around an area of the target tissue, the electrical signal being a stochastic signal; (b) transforming the stochastic signal into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm; (c) comparing a graph of a resultant FFT level of the target tissue to at least one graph of a baseline FET level; and (d) determining a current state of the target tissue based on the comparison.
[0022] According to a further teaching of the present invention, the detecting and recording is implemented as detecting and recording an alternating current (AC) signal and displaying the alternating current (AC) signal as voltage over time.
[0023] According to a further teaching of the present invention, the FFT level is implemented as an electrical frequency spectra from 0 to 5000 Hz.
[0024] According to a further teaching of the present invention, the FFT level is implemented as an electrical frequency spectra from 0 and 3000 Hz.
[0025] According to a further teaching of the present invention, the target tissue is an area of injury in a patient.
[0026] According to a further teaching of the present invention, the baseline is implemented as the FFT levels for healthy non-injured subjects.
[0027] According to a further teaching of the present invention, the baseline is implemented as an FFT level for normal healthy tissue and an increase in the FFT level of the target tissue relative to the baseline FFT level is indicative of wound conditions.
[0028] According to a further teaching of the present invention, the current state of the target tissue includes one from a list that includes worsening condition, healing condition and stopped condition.
[0029] According to a further teaching of the present invention, the FFT level of the target tissue is implemented so as to enable differentiation of wounds that are in a worsening condition due to infection from wounds that are in a healing state and from wounds that are in a stopped state.
[0030] According to a further teaching of the present invention, there is also provided comparing the graph of a resultant FFT level of the target tissue to FFT level referenced markers.
[0031] According to a further teaching of the present invention, the FFT level reference markers are implemented so as to indicate wounds in a worsening state, a healing state and a stopped state
[0032] According to a further teaching of the present invention, the FFT level reference markers are implemented as mean FFT level profiles detected in healthy subjects, patients with chronic wounds diagnosed as worsening, patients with chronic wounds diagnosed as healing and patients with chronic wounds diagnosed as stopped.
[0033] According to a further teaching of the present invention, there is also provided: (a) providing data regarding the current state of the target tissue to a devise for transmitting an alternate current to the target tissue; and (b) transmitting an alternate current signal to the target tissue wherein a specific frequency spectra is determined by the data.
[0034] According to a further teaching of the present invention, the determining further includes determining a prognosis for the target tissue.
[0035] There is also provided according to the teachings of the present invention, a method for determining a prognosis for wounds in a living human and animal target tissue, the method comprising: (a) detecting and recording a first electrical signal in and around an area of the target tissue a second electrical signal in and around contralateral tissue, the first and the second electrical signals being a stochastic signals; (b) transforming the first and the second electrical signals into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm; (c) comparing a graph of a resultant FFT level of the first electrical signal to at least one graph of a baseline FFT level and an FFT level of the second electrical signal; and (d) determining a prognosis of the target tissue based on the comparison.
[0036] There is also provided according to the teachings of the present invention, a method of a prognosis for wounds in living human and animal target tissue, the method comprising: (a) detecting and recording an electrical signal in and around an area of the target tissue, the electrical signal being a stochastic signal; (b) transforming the stochastic signal into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm; (c) comparing a graph of a resultant FFT level of the target tissue to at least one FFT level referenced marker; and (d) determining a current state of the target tissue based on the comparison.
[0037] According to a further teaching of the present invention, the FFT level reference markers are implemented so as to indicate wounds in a worsening state, a healing state and a stopped state
[0038] According to a further teaching of the present invention, the FFT level reference markers are implemented as mean FFT level profiles detected in healthy subjects, patients with chronic wounds diagnosed as worsening, patients with chronic wounds diagnosed as healing and patients with chronic wounds diagnosed as stopped.
[0039] There is also provided according to the teachings of the present invention, an electrical stimulator system for providing treatment to a target tissue, the electrical stimulator system comprising: (a) a first component configured for detecting and recording an electrical signal in and around an area of the target tissue, the electrical signal being a stochastic signal, the device further configured to transform the stochastic signal into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm, use a resultant FFT level to generate data regarding a current state of the target tissue and transmit the data; (b) a second component configured to deliver an electrical current to the target tissue, the devise configured to receive the data from the first component, characteristics of the electrical current being determined by the data.
[0040] According to a further teaching of the present invention, the characteristics include a specific frequency spectra.
[0041] According to a further teaching of the present invention, the electrical current delivered to the target tissue is an alternate current signal.
[0042] There is also provided according to the teachings of the present invention, a method of determining the presence of infection in a worsening wound in living human and animal tissue, the method comprising: (a) detecting and recording a first electrical signal in and around an area of the target tissue a second electrical signal in and around contralateral tissue, the first and the second electrical signals being a stochastic signals; (b) transforming the first and the second electrical signals into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm, (c) comparing a graph of a resultant FFT level of the first electrical signal to an FFT level of the second electrical signal and at least one graph of a baseline FFT level of wounds in a worsening state without infection; and (d) determining a presences of infection in the target tissue based on the comparison.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
[0044] FIG. 1 illustrates placement of electrodes near a wound;
[0045] FIG. 2 illustrates the placement of electrodes near a wound and on the contralateral healthy limb;
[0046] FIG. 3A is a graph of raw baseline data for a healthy subject;
[0047] FIG. 3B is a graph of baseline data of FIG. 3A after transformation to FFT levels;
[0048] FIG. 3C is a graph of baseline data of FIG. 3B when filtered;
[0049] FIG. 4 is a graph of the FFT baseline for healthy subjects;
[0050] FIG. 5 is a graph of the FFT baseline for healthy subjects, the FFT level for chronic wounds and the FFT level for the contralateral non-injured tissue of the subjects with wounds;
[0051] FIG. 6 is a graph of the FFT baseline for healthy subjects and the FFT level for wounds in a stopped state;
[0052] FIG. 7 is a graph of the FFT baseline for healthy subjects and the FFT level for wounds in a worsening state;
[0053] FIG. 8 is a graph of the FFT baseline for healthy subjects and the FFT level for wounds in a healing state;
[0054] FIG. 9 is a graph of the FFT baseline for healthy subjects, the FFT level for wounds in a stopped state, the FFT level for wounds in a worsening state and the FFT level for wounds in a healing state;
[0055] FIG. 10 is a chart that summarizes the statistical analysis/comparisons between the groups;
[0056] FIG. 11 is a graph the FFT level around a chronic wound and the FFT level for the contralateral non-injured tissue for the group of subjects having wounds in a worsening state without injection;
[0057] FIG. 12A-12E are graphs the FFT level around a chronic wound and the FFT level for the contralateral non-injured tissue for five individual subjects having wounds in a worsening state due to infection;
[0058] FIG. 13 is a flowchart of a method, according to the teachings of the present invention, of determining if a worsening wound in target tissue is infected;
[0059] FIG. 14 is a flowchart of a method, according to the teachings of the present invention, for detecting the current state of living human and animal target tissue;
[0060] FIG. 15 is a flowchart of a first method, according to the teachings of the present invention, for determining a prognosis for wounds in living human and animal target tissue; and
[0061] FIG. 16 is a flowchart of a second method, according to the teachings of the present invention, for determining a prognosis for wounds in living human and animal target tissue.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0062] The present invention relates to a diagnostic method that identifies and defines a discrete electrical profile of a wound during a healing, worsening or stopped condition so as to provide a prognosis for such wounds.
[0063] The principles and operation of a diagnostic method that identifies and defines a discrete electrical profile of a wound so as to provide a prognosis for such wounds according to the present invention may be better understood with reference to the drawings and the accompanying description.
[0064] By way of introduction, electrical flow in the body plays a major role in many physiological and pathophysiological conditions. During tissue injury, direct electrical current known as “the current of injury” is triggered (or generated) around the wound. However, alternating current characterized by specific frequencies, is mainly attributed in medicine to the action or injury of nerves but with much less focus on wounds. Research by the present inventors has identified in humans the presents of discrete alternating current signals that are specific to patients with chronic wounds in comparison to healthy subjects. They conducted simultaneous alternating current measurements on the same patients at their injured where there is an existing chronic wound and on the contralateral non injured limb. They then activated an algorithm to transform these stochastic signals to frequency spectra and found that the same signal pattern exists around the wound and throughout the patient's body. These discrete microcurrent signals display unique frequency profiles within the range of 0.5-500 Hz. Furthermore, electrical recordings of chronic wounds taken during an acute injury state induced by their debridement revealed an instantaneous stochastic signal with a frequency pattern exceeding 1000 Hz, a signal that was triggered simultaneously around the acute wound and on the contralateral healthy limb of the same patient. Their findings emphasize the possible systemic attribute of alternating current signaling in wound healing. They indicate that this electrical signaling may be linked to a possible “cross talk” between the central nervous system and wounds. They suggest that electrical frequencies should be considered as a relevant marker to study wound healing.
[0065] Whereas research on direct current (DC) in wound healing and tissue remodeling has a long history, electric fields of alternating current (AC) with specific frequencies have been much less studied.
[0066] Specific frequencies have been detected in various biological pathways known to be associated with wound healing such as pain, cell metabolism, inter-cellular communication and bone growth. However, due to the absence of suitable measurement tools, there has been no definitive proof of involvement of AC with defined frequency spectra in wounds.
[0067] In their research the present inventors aimed to elucidate whether oscillating characteristics of specific frequency components exist around injured tissues in humans. They wished to identify discrete AC cues linked to a specific spectrum of frequencies adjacent to chronic non-healing wounds and to determine whether these AC cues could be detected during acute injury.
[0068] For this objective, on the same group of patients we conducted electrical recordings on both injured and on non-injured tissue, with the measurements on non-injured tissue used for control.
[0069] For electrical recordings we affixed two electrodes on both proximal and distal sides across the medial axis of the injured skin ( FIGS. 1 and 2 ) and signals were measured against the third ground electrode (not shown). In order to amplify the specificities of the recorded AC signals a Fast Fourier Transform (FFT) algorithm was used. By this signal processing approach they were able to profile discrete signals with significant differences in amplitude (voltage) and/or frequency within a filter set at 0.5 to 1000 Hz.
[0070] To establish the baseline levels of our electrical measurements, we recruited healthy subjects (no wounds) and the graph of their mean FFT levels served as the minimal amplitude levels i.e., baseline.
[0071] To test the role of endogenous electrical frequencies in damaged tissue, we first focused on patients with chronic wounds as the target population. Chronic wounds are trapped in a non-advancing phase of healing and are unable to progress through the sequential stages of tissue repair. Compared to acute wounds, studies have shown that human chronic wounds differ in their biochemical, molecular and mechanistic characteristics such as reduced levels of metalloproteinase inhibitors and diminished growth factor activity. Therefore, unlike acute wounds that are dynamically changed in time, chronic wounds may be considered relatively stable and thus could provide an example of the profile of their mean electric fields. The mean electrical measurements around chronic wounds exhibited significantly higher amplitude (voltage) above the baseline measurements in healthy subjects. These stochastic signals were characterized by mean electrical frequency spectra within the range of 0.5 to 500 Hz. The mean maximum voltage (Vmax) of this signal was found in the range of 0.5 to 50 Hz (a frequency range considered as environmental electrical radiation). The signal reduced exponentially to its minimal voltage (Vmin) of about 10 nV which was detected around 500 Hz. Due to the absence of such signals in the baseline group of healthy subjects we confirmed that this discrete signal is specific to chronic wounds.
[0072] In order to confirm that the specific signal detected around wounds is specific to the wound site, similar measurement on the contralateral healthy limb of the same chronic wound patients. Intriguingly, it was found in the same patients that the stochastic waveform that exists around wounds, overlapped with same electrical frequency spectra and amplitude of the signals recorded on the contralateral non-injured organ. It is therefore deduced that the discrete stochastic signals found in patients with chronic wounds could also serve as a systemic parameter in the body. These statistically significant results ( FIG. 4 ) highlight the possibility that chronic wounds may be studied as local tissue damage with systemic attributes.
[0073] To investigate the origin of the local and systemic signals found around chronic wounds, it was necessary to find how this type of stochastic signal is produced in the body. Although studies on “the current of acute injury” have claimed that this is a type of DC signal, we speculated that the stochastic signals identified here in chronic wounds may originate from prior AC signals produced during the acute stages of these chronic wounds. To address this hypothesis, patients with diagnosed chronic wounds that were allocated to a surgical debridement procedure were recruited. The clinical rationale of chronic wound debridement is to release the chronic wound from its arrested state by removing nonviable tissue, bacteria, and other inhibitory factors, effectively converting it into an acute wound that can undergo healing more effectively. Considering the research study prospective, the debridement procedure provided an excellent example for evaluating the dynamics of electrical frequency pattern before and during this procedure. It should be emphasized that in these cases it was possible to simultaneously analyze the dynamics of the signals before and during acute injury on both the wound and contralateral non-injured organs. The generated signal exhibited significantly higher amplitude above the amplitude levels of the basal signal and its frequency spectra exceeded 1000 Hz much above the chronic wound signals. Furthermore, the present inventors found the intriguing result of the simultaneous increase and existence of these injury signals on both the wound and on the contralateral healthy limb of the same patients. Considering that the debridement procedures were done here with no aid of anesthesia, the findings on the instantaneously triggered signals during this acute injury indicate a possible involvement of somatosensory afferent or efferent nerves in this signaling. Furthermore, preliminary electrical recordings on anesthetized patients (blockage of sensory nerves) show that during incision i.e., in acute wounds, we detected AC signals with considerably weak amplitudes (around the baseline levels), another indication that nerves or nerve injury may be involved in the AC signaling found here during acute injury.
[0074] The existence of defined specific electrical frequencies in the central nervous system is well documented in medicine, and these are fundamental markers in the monitoring and studies of brain activity. Despite studies on pain, the role of electrical frequencies in other peripheral disorders such as tissue injury have been much less studied. The results of the research done by the present inventors clearly demonstrate the relevance of electrical frequencies in the electrophysiology of the body's periphery; the research focused on both chronic wounds and on acute injury. Under the experimental conditions, acute injury elicits AC signals with significantly higher amplitude and frequency than those detected around chronic wounds. The findings on the discrete frequency pattern triggered during the acute injury of chronic wounds, both at injured and non-injured tissue provide a new perspective on the reported DC “current of injury”.
[0075] Based on the above research, the method of detecting the prognosis of wounds in a patient of the present invention was developed. The method of detecting the prognosis of wounds in a patient of the present invention includes detecting and record an electrical signal, specifically alternating current displayed as voltage during time, from the patient, wherein the electrical signal is a stochastic signal. The stochastic signal is then transformed to voltage versus frequency spectra by the Fast Furier Transform (FFT) algorithm. The FFT graph comprises an electrical frequency spectra from 0 to 5000 Hz and more specific to 0 and 1000 Hz.
[0076] The FFT level of the wound sample is then compared to the (baseline) FFT level in a normal sample, such as a healthy subject for example. An increase in the level of the FFT relative to the normal sample is indicative of wound conditions.
[0077] Therefore, the prognostic method of the present invention can also be a prognostic scale, or a prognostic electrical scale, with a discrete FFT such that the FFT is specific to chronic wounds that enables to differentiate between wounds that are in a worsening state, wounds that are in healing state and wounds that are neither worsening nor healing but are in a stopped state.
[0078] The stochastic signal is detected by using alternating current measurements with the signal displayed as voltage during time.
[0079] The stochastic signal transformed to FFT may be displayed as voltage as a function of frequencies, such that the FFT level is defined as the area under the voltage versus frequency curve.
[0080] An alternating current probe may be used to detect the stochastic signal that is then transformed by algorithm to FFT.
[0081] It will be understood that the probe may include, but is not limited to, electrodes, anodes, and cathodes, placed around the wound. A ground reference electrode may be placed on the skin contralateral healthy limb.
[0082] The prognostic scale of the present invention may use the mean FFT of healthy subjects as the baseline value to define a wound as worsening, healing or stopped.
[0083] Alternatively and/or additionally, the prognostic scale of the present invention may use reference markers taken from healthy tissue, worsening wounds, healing wounds and stopped wounds to define a wound as worsening, healing or stopped.
[0084] The reference markers may be, by non-limiting example, the mean FFT profiles detected in healthy subjects, patients with chronic wounds diagnosed as worsening, patients with chronic wounds diagnosed as healing and patients with chronic wounds diagnosed as stopped.
[0085] It will be appreciated that the prognosis scale of the present invention may be operationally linked to a device for delivering alternating current to human tissue such that upon determination of the current status of the wound, the device transmits to the tissue an alternating current with specific frequency spectra for worsening, healing or stopped wounds.
[0086] Referring now to the drawings in more detail, FIGS. 1 and 2 illustrate the electrical recordings procedure of the present invention which affixing two electrodes 2 and 4 on both proximal and distal sides across the medial axis of the injured skin 6 and signals were measured against the third ground electrode (not shown). For simultaneous comparison two AC recording devices can be used, as seen in FIG. 2 , with one device 8 placed around the wound and the other 10 device on the contralateral healthy limb 12 for real time comparison. It will be appreciated that device 8 may electrical stimulator system for providing treatment to a target tissue that includes a first component configured for detecting and recording an electrical signal in and around an area of the target tissue 6 , transform the signal into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm, use a resultant FFT level to generate data regarding a current state of the target tissue and transmit the data to a second component configured to deliver an electrical current to the target tissue 6 , such that the characteristics of the electrical current delivered is determined by the data regarding a current state of the target tissue.
[0087] FIG. 3A illustrates the AC signal displayed during time (voltage against time) is a stochastic cue. In order to amplify the specificities of this signal, an algorithm of Fast Fourier Transform (FFT) is applied. This transformation enables to display the original detected signal as voltage versus frequency spectra as illustrated in FIG. 3B . This signal processing approach enables the profiling of discrete signals with significant differences in amplitude (voltage) and/or frequency within a filter set at 0.5 to 1000 Hz and up to 2000 Hz. In order to improve the signal to noise of the FFT (sampling rate of 16 per 1 second) the sampling rate is reduced to one sample per second (1 Hz) by the this an improved signal obtained with less noises as seen in FIG. 3C .
[0088] To establish the baseline levels of electrical measurements on patients, measurements conducted on healthy subjects (no wounds) and their mean FFTs served as the minimal amplitude levels i.e., baseline. FIG. 4 shows the mean frequency spectra detected on the healthy skin of healthy subjects that served as the baseline for the prognosis of wounds.
[0089] FIG. 5 is a graph of the FFT baseline for healthy subjects 40 , the FFT level for chronic wounds 50 and the FFT level for the contralateral non-injured tissue of the subjects with wounds 52 . The mean electrical measurements around chronic wounds 50 exhibited significantly higher amplitude (voltage) above the baseline measurements of healthy subjects 40 . These stochastic signals were characterized by mean electrical frequency spectra within the range of 0.5 to 1000 Hz. The mean maximum voltage (Vmax) of this signal was found in the range of 0.5 to 50 Hz (the frequency spike around 50 Hz is considered as environmental electrical radiation). The signal reduced exponentially to its minimal voltage (Vmin) of about 10 nV which was detected around 200 and up to 1000 Hz (in the baseline curve) and of about 20 nV within the range of 700 to 1000 Hz in the chronic wounds group. The significant higher Area Under the Curve (AUC) of the chronic wounds signals above the baseline confirmed that this discrete signal is specific to chronic wounds.
[0090] A comparable measurement was conducted on the same patient by a similar measurement procedure on the patient contralateral healthy limb. The figure shows that in the same patients the stochastic waveform which exists around wounds, overlapped with same electrical frequency spectra and amplitude on the contralateral non-injured organ 52 . This means that the discrete stochastic signals found in patients with chronic wounds could also serve as a systemic marker in the body.
[0091] FIG. 6 shows the significant higher amplitudes exhibited by the mean FFT levels of the group of patients having wounds in stopped condition 60 above the mean FFT levels of healthy subjects 40 .
[0092] FIG. 7 shows the significant higher amplitudes exhibited by the mean FFT levels of the group of patients having wounds in worsening condition 70 above the mean FFT levels of healthy subjects 40 .
[0093] FIG. 8 shows the significant higher amplitudes exhibited by the mean FFT levels of the group of patients having wounds in healing condition 80 above the mean FFT levels of healthy subjects 40 .
[0094] FIG. 9 shows the comparison between the graphs of FIGS. 6-8 . Specifically, the FFT levels for healthy subject to patients with chronic wounds heaving in a stopped state 60 , worsening state 70 or healing state 80 . The figure shows that significant differences are found between the three prognostic levels of wounds. The worsening and healing are above stopped and all three are higher that the baseline of healthy subjects 40 .
[0095] FIG. 10 summarizes the statistical analysis/comparisons between the groups. The F value 100 which is <0.0001, shows the significance of the differences between wounds in the; stopped state 104 , worsening state 108 and healing state 112 in comparison to the baseline healthy subjects 114 . The chart also shows that the mean values of contralateral healthy limb 102 , 106 and 110 for each group respectively can be used as a marker for wound prognosis. It should be noted that while the mean values of worsening 108 and healing 112 wounds are close to each other, their relationship to the mean values of their respective contralateral healthy limbs 106 and 110 are noticeably different.
[0096] FIG. 11 is a graph the FFT level around a chronic wound 110 and the FFT level for the contralateral no injured tissue 110 ′ for a group of subjects having wounds in a worsening state without injection. FIGS. 12A-12E are graphs the FFT level around a chronic wound 120 and the FFT level for the contralateral non-injured tissue 120 ′ for five individual subjects having wounds in a worsening state due to infection. It will be readily appreciated that in the group having wounds in a worsening state without injection ( FIG. 11 ) the FFT level around the chronic wound 110 and the FFT level for the contralateral non-injured tissue 110 ′ are substantially the same and the line for the FFT level around the chronic wound 110 is obscured by the line FFT level for the contralateral non-injured tissue 110 ′. In contrast, the FFT level around the chronic wound 120 and the FFT level for the contralateral non-injured tissue 120 ′ for the five individual subjects having wounds in a worsening state due to infection ( FIGS. 12A-12E ) are both statistically and visually quite different. Therefore, according to the teaching of the present invention, it is possible to distinguish wounds in a worsening state due to infection from wounds in a worsening state without injection. Therefore, the present invention includes, as illustrated in the flowchart of FIG. 13 a method of determining if a worsening wound in living human and animal tissue is infected. The method including the steps of:
13 - 1 Detecting and recording a first electrical signal in and around an area of the target tissue a second electrical signal in and around contralateral tissue, the first and the second electrical signals being a stochastic signals. 13 - 2 Transforming the first and the second electrical signals into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm. 13 - 3 Comparing a graph of a resultant FFT level of the first electrical signal to an FFT level of the second electrical signal and at least one graph of a baseline FFT level of wounds in a worsening state without infection. 13 - 4 Determining the presences of infection in the target tissue based on the comparison.
[0101] FIG. 14 illustrates a method of the present invention for detecting the current state of living human and animal target tissue. The method includes the steps of:
14 - 1 Detecting and recording an electrical signal in and around an area of the target tissue, the electrical signal being a stochastic signal. 14 - 2 Transforming the stochastic signal into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm. 14 - 3 Comparing a graph of a resultant FFT level of the target tissue to at least one graph of a baseline FFT level. 14 - 4 Determining a current state of the target tissue based on said comparison.
[0106] FIG. 15 illustrates a first method of the present invention for determining a prognosis for wounds in living human and animal target tissue. The method includes the steps of:
15 - 1 Detecting and recording a first electrical signal in and around an area of the target tissue a second electrical signal in and around contralateral tissue, the first and the second electrical signals being a stochastic signals. 15 - 2 Transforming the first and the second electrical signals into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm. 15 - 3 Comparing a graph of a resultant FFT level of the first electrical signal to at least one graph of a baseline FFT level and an FFT level of the second electrical signal. 15 - 4 Determining a prognosis of the target tissue based on the comparison.
[0111] FIG. 16 illustrates a second method of the present invention for determining a prognosis for wounds in living human and animal target tissue. The method includes the steps of:
16 - 1 Detecting and recording an electrical signal in and around an area of the target tissue, said electrical signal being a stochastic signal. 16 - 2 Transforming said stochastic signal into a voltage versus frequency spectra using a Fast Furier Transform (FFT) algorithm. 16 - 3 Comparing a graph of a resultant FFT level of the target tissue to FFT level referenced markers. 16 - 4 Determining a current state of the target tissue based on said comparison.
[0116] It will be appreciated that the above descriptions are intended only to serve as examples and that many other embodiments are possible within the spirit and the scope of the present invention. | Described herein are electrical markers, specifically alternate current (AC) signals whose appearance in patients with wounds, specifically chronic wounds, correlates to the prognosis of the wounds. Related methods that can be used for diagnosis and treatment of wounds are disclosed. Also described herein are methods that can be used to identify electrical signals of wounds. | 0 |
BACKGROUND OF THE INVENTION
The present invention is in the field of metal construction shapes and particularly those shapes used in the construction of metal windows and doors and frames therefor.
With the advent of metal construction used in curtain wall and other metal window and door enclosures, problems of heat conduction have arisen. The use of aluminum for the metal frames caused a greater transfer of heat between wall elements than had heretofore taken place in previous types of such construction. An insulation problem or the necessity for a thermal break construction element was thus essential. Various types of thermal breaks have been constructed, some of which have been satisfactory, but have been too costly. Other types have met with varying degrees of success.
Most thermal break constructions are currently formed by pouring in place an insulating material into the metal members or by mechanically joining the metal members and insulating member by deformation of the metal members. U.S. Pat. Nos. 3,204,324, 3,393,487, 3,624,885, 3,634,565 and 3,823,524 are illustrative of the former type of constructions. U.S. Pat. Nos. 3,093,217, 3,114,179, 3,420,026, and 3,411,995 are illustrative of the latter type of construction. U.S. Pat. Nos. 3,411,254, 3,289,377, 3,055,463 and 2,654,920 disclose additional prior art thermal break constructions.
Another means of mechanically joining metal members with an insulating member is disclosed in U.S. application Ser. No. 430,099, filed on Jan. 2, 1974, having a common ownership with the instant application. In this method, dimensional tolerances are essential to obtain a desired interference fit.
The present invention eliminates the necessity of expensive jigs which are required with pouring operations.
The instant invention permits some variances in dimensional tolerances providing a more economical construction.
Heat generated by metal deformation is also eliminated and metal marring and defacing is reduced.
Thermal break construction joints or lineal shapes of this invention have uniform strength and are relatively simple and easy to fabricate. The use of jig boxes and table space is also minimized.
It is a primary object of the present invention to provide a unitary thermo break connection or a thermally insulating break in metal construction shapes utilizing a rigid insulating member adapted to be mechanically received by the metal shapes which eliminates the need for exact dimensional tolerances.
SUMMARY OF THE INVENTION
The present invention relates broadly to a thermal barrier member or shape, preferably made of rigid plastic or other suitable insulating material, which has a plurality of small surface protrusions or projections thereon located at predetermined areas on the member and which is adapted to be received by metal members. Lineal metal members or metal shapes are constructed so as to receive the insulating member and provide a unitary thermal break construction joint or thermo break connections. In effect, three lineal shapes, two metal and one insulating, are mechanically longitudinally joined together to form a composite building shape. In joining the shapes together, end portions of the small projections on the insulating shape are shaved off or sheared by exposed edges of the harder metal mating shapes. A tight connection or interference fit is thus achieved.
The insulating or thermal barrier member is preferably an extruded or molded rigid plastic and may be made from any suitable material such as PVC, nylon, urethane, styrene, polyethylene, hard rubber and the like. The metal shapes are preferably aluminum and may be extruded, cast, wrought or otherwise formed. The term aluminum includes aluminum and aluminum alloys customarily used in the construction industry, especially in the manufacture of windows, doors, curtain walls and frames therefor. Aluminum extrusions are preferred.
Although some degree of dimensional tolerances are essential, the unique construction of this invention permits the metal shapes to conform to irregularities and dimensional variations.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view in cross-section illustrating one type of a thermal barrier member of the invention;
FIG. 2 is a view in cross-section illustrating another type of a thermal barrier member;
FIG. 3 is a view in cross-section illustrating still another type of thermal barrier member;
FIG. 4 is a view in cross-section illustrating the FIG. 3 embodiment and corresponding metal members to which it is to be joined thereto;
FIG. 5 is a view similar to that of FIG. 4 illustrating the thermal barrier member of FIG. 3 after it has been joined to the metal members to form a unitary thermo break or insulating joint or construction;
FIG. 6 is a view in cross-section of a portion of the FIG. 3 embodiment illustrating the details of the small surface protrusions or projections on the thermal barrier member;
FIG. 7 is a view in cross-section of a portion of the FIG. 4 embodiment illustrating the details of the projections after the insulating and metal members have been joined together; and,
FIG. 8 is a perspective view illustrating one means of joining together the thermal barrier or insulating member and metal members of FIGS. 4 and 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIGS. 1, 2 and 3 illustrate in cross-section various lineal plastic shapes designated 10, 20 and 30, respectively, which are suitable for use in the present invention. For simplicity of construction, the upper and lower portions of the plastic shapes are substantially identical. Each of the shapes has a plurality of relatively small projections or surface protrusions 11, 21 and 31, respectively, thereon which extend longitudinally the length of the shape. The projections are so located on the plastic shapes and so constructed thereon as to make a shearing contact with their respective mating metal members as will be more fully explained hereinafter.
It can be appreciated that the insulating members may be of various configurations. The small projections may be located in female type openings, such as shown in the members 10 and 30 or may be located on male type members, such as seen in the shape 20.
In the FIGS. 1 and 3 embodiments, openings or channels 12 and 32 are formed in the members 10 and 30, respectively, for receiving mating projections on metal members. The small projections 11 and 31 extend into their respective openings a desired or predetermined amount. Additional projections may be added as required or desired. The openings or channels 12 and 32 are of a generally or somewhat rectangular construction when viewed in cross-section and extend the length of the shape therein.
In the FIG. 2 embodiment, the member 20 is somewhat "T"-shaped on each end thereof and has a pair of somewhat diamond shaped or male members 21 extending inwardly from each cross-bar 22. The cross-bars and male members thereon extend longitudinally the length of the shape 20. The male members 21 are so constructed that end portions or small projections 23 are formed thereon. The projections 23 are adapted so as to make a shearing contact with metal members adapted to receive the male members 21.
A shape, either plastic or metal, is defined as a product that is long in relation to its cross-sectional dimensions and has a cross-section other than that of sheet, plate, rod, bar, tube or wire.
The size and weight of the plastic members and their corresponding metal members is largely determined by strength and use specifications. In general, sizing of the thermal barrier is a function of obtaining the overall strength, i.e., the minimum thickness required for a given application and the desired interference fit between the plastic and metal members.
Of the plastics suitable for constructing the thermal barrier shape, PVC (polyvinylchloride) is preferred. The plastic shape may be formed by extrusion, molding or other processes, with the former being preferred.
Referring now to FIGS. 4--7, the relationship of the member 30 to joining metal members 40 and 50 is illustrated. The metal members 40 and 50 are constructed so as to be mateable with the member 30. The portions of the metal members 40 and 50 which are joined to the member 30 are substantially identical. It can be appreciated that the parts (not shown) of the metal members which extend away from the mating area or part can be of various configurations depending upon the end use of the thermal break joint or connection.
The member 40 has a channel or "U"-shaped end 41 formed by members 42, 43 and 44. The member 43 has a pair of "L"-shaped or right angled shaped projections 45 extending perpendicularly from one side thereof. The projections 44 extend longitudinally the length of the shape 40. Channels or openings 46 are formed by the end portion or male members 47 of the members 45, perpendicular members 48 of the member 45 and end segments 49 of the member 43.
The members 47 are sufficiently narrow that they can be received by the openings 32 in the member 30 but are also sufficiently wide that during the insertion of the members 47 into the openings 32, end portions of the small projections 31 are shaved off or sheared (FIGS. 5 and 7).
The metal member 50 is similarly constructed as the member 40 and has a channel member 51 formed by members 52, 53 and 54. The member 53 has a pair of right angled shaped projections 55 extending perpendicularly from one side thereof. The projections 54 extend longitudinally the length of the shape 50. Channels or openings 56 are formed by male members 57 of the members 55, perpendicular members 58 of the members 55, and end segments 59 of the member 53.
As in the case of the members 47, the members 57 are of a sufficiently narrow width that they can be received by the openings 32 in the member 30, but are also of a sufficient width that during the insertion of the members 57 into the openings 32, end portions of the small protrusions 31 are sheared or shaved off.
After the metal members 40 and 50 have been joined together by the plastic or insulating member 30, as will be explained more fully hereinafter, a unitary thermo break or thermal barrier joint or connection is formed. When the plastic and metal members have been formed, the projections 47 are tightly fit in the openings 32 and the external or outer edges or surfaces 30a of the member 30 are in alignment with the outer edges 42a of member 42 and 52a of member 52 and the outer surfaces 30b of the member 30 are in alignment with the outer edges 44a of member 44 and 54a of member 54.
In joining the metal members 40 and 50 to the plastic member 30, the metal members are aligned parallel to each other in a spaced apart relationship as shown in FIG. 8 with angle shaped projections 47 and 57 facing each other. The metal members may be held in place by jigs or other suitable apparatus or even manually, if desired.
The plastic member 30 is placed in a position before the opening between the metal members and is moved longitudinally between the metal members. Preferably, the member or shape 30 is force fed into the opening between the metal members by suitably located spaced apart rollers 60. The drive shafts 61 of the rollers are parallel to the large flat surfaces 30a and 30d of the shape 30. This arrangement permits the application of high pressure on the plastic when feeding the shape into adjoinment with the metal members without crushing or damaging the plastic material.
As the member 30 is introduced into the space between the metal members 40 and 50, the edges of the metal male members 47 and 57 are met or contacted by end portions 31a of the projections 31 of the member 30. As force is applied to the shape 30 to move it longitudinally and slidably between the members 40 and 50, the harder metal edges cause the end portions 31a to be sheared or shaped off, as the male members 47 and 57 receive their respective openings 32. As seen in FIG. 7, this results in a tight or interference fit between the plastic and metal members and a unitary thermal break construction shape is formed.
As can readily be seen, this unique construction avoids the necessity for costly highly exact tolerances in the manufacture or extrusion of plastic and metal shapes. Minor irregularities in dimensions present no problems, as all or part of the small protrusions 31 may be sheared or removed in the joining process and a tight fit can still be obtained.
It can be appreciated that various mating arrangements of plastic and metal members can be constructed. It is only essential that the plastic members have small protrusions or projections thereon, which are adapted to be all or partially removed when mated or joined with their corresponding metal members, and which are so located or positioned on the plastic member and in sufficient numbers to provide a desired interference fit.
It is of course also essential that the mating portion of the metal members be of a size and configuration so as to properly receive the mating portions of the insulating member and to effect the necessary shearing action to remove at least an end portion of the small projections or protrusions on the insulating member to thereby obtain the desired interference fit.
The metal members may have male joining members extending therefrom adapted to be mated with openings or female parts of the insulating member or the metal members may have members extending therefrom which have openings or female parts therein for mating with male members extending from or on the insulating member.
The foregoing disclosure and description of the invention is only illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated contruction, may be made within the scope of the appended claims without departing from the spirit of the invention. | A method of making a thermal barrier shape or lineal construction element wherein a pair of lineal metal shapes adapted to receive a lineal insulating member or shape are aligned with each other in generally parallel spaced apart relation and the lineal insulating member or shape having small lineal projections thereon is slidably inserted between the metal shapes to join them together and form the thermal barrier shape. During joining, end portions of the projections on the insulating shape are shaved off to provide a tight fit between the metal and insulating shapes.
This is a division of application Ser. No. 580,975 filed on May 27, 1975. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to polyisocyanurate foams prepared from partially etherified methylolamines with polyisocyanates in the presence of trimerization catalysts.
2. Description of the Prior Art
The prior art generally teaches the preparation of isocyanurate-modified foam products.
U.S. Pat. No. 4,139,501 teaches the preparation of polyurethane foam with enhanced flame retardancy by the reaction of a polyol and an organic polyisocyanate in mixture with a hydroxylmethylmelamine derivative and including therein a halogenated phosphorus ester.
U.S. Pat. No. 4,197,373 teaches the preparation of flame retardant polyurethane foams from a reaction mixture containing the reaction products of melamine and chloral and optionally alkylene oxide adducts thereof.
U.S. Pat. No. 3,135,707 teaches the use of partially alkylated polymethylolmelamines for the preparation of polyurethane foams. There is no teaching in the prior art that improved flame retardant polyisocyanurate foams may be prepared employing partially etherified methylolmelamines either alone or in combination with other polyols.
SUMMARY OF THE INVENTION
The present invention relates to the preparation of polyisocyanurate foams by reacting partially etherified methylolmelamines with polyisocyanates in the presence of trimerization catalysts.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In accordance with the invention, etherified methylolmelamines are prepared by reacting an aqueous solution of formaldehyde with melamine employing an alkaline catalyst. After the reaction has proceeded at elevated temperatures, an etherifying hydroxyl containing compound is added, followed by an acid catalyst and the etherification process is allowed to proceed. After the reaction is complete, the product is obtained by neutralization of the acid filtration of the salts, and vacuum stripping of the volatiles.
The etherified methylolmelamine employed in the invention is the condensation product of melamine and formaldehyde in the first stage of the reaction. In the second stage, etherification is accomplished by reacting an alcohol with the methylolmelamine to form a product having the following formula: ##STR1## wherein n is an integer from 0 to 2
R is selected from the group consisting of
--OH,
--O--C x H 2x+1 ,
--O--C x H 2x OC x H 2x OH,
--O--C x H 2x-y+1 Y y ,
--O--C z H 2z-1 , ##STR2## --O--C x H 2x NH--R', --O--C x H 2x --NH--C x H 2x --OH, ##STR3## and --O--C x H 2x --O--R'
wherein y is an integer from 1 to 3 and R' is an alkyl containing 1 to 4 carbon atoms, x is an integer from 1 to 5, Y is bromine or chlorine, and z is an integer from 2 to 5 and with the proviso that at least two of the R groups are OH.
The preferred ratio of formaldehyde to melamine is 7:1 to 8:1 while the preferred ratio of alcohol to melamine is 13:1 to 15:1.
Any alkaline catalyst may be employed. Examples include sodium hydroxide, potassium hydroxide, sodium methoxide etc. The acid catalysts which may be employed are nitric acid, hydrochloric acid, phosphoric acid and sulfuric acid. The hydroxyl group containing compounds which may be employed for the etherification are those which have the formula:
C x H 2x+1 OH,
HOC x H 2x OC x H 2x OH,
C x H 2x-y+1 Y y OH,
C z H 2z-1 OH,
HOC x H 2x NH--R',
HO--C x H 2x --NH--C x H 2x --OH, ##STR4## and HO--C x H 2x --O--R'
wherein x, y, z, R' and Y are as defined above.
It is further contemplated that compounds having the formula: ##STR5## may be employed wherein R' is an alkyl radical containing from 1 to 4 carbon atoms.
The phosphorus compounds are generally employed in combination with the other compounds listed above in order to provide that at least two R groups are OH.
The partially etherified methylolmelamines are reacted with polyisocyanates in the presence of trimerization catalysts and blowing agents to produce polyisocyanurate foams.
The organic polyisocyanate employed in the instant invention corresponds to the formula R'(NCO)z where R' is a polyvalent organic radical which is either aliphatic, arylalkyl, alkylaryl, aromatic or mixtures thereof and z is an integer which corresponds to the valence of R' and is at least 2. Representative of the types of organic polyisocyanates contemplated herein include, for example, 1,2-diisocyanatoethane, 1,3-diisocyanatopropane, 1,2-diisocyanatopropane, 1,4-diisocyanatobutane, 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, bis(3-isocyanatopropyl)ether, bis(3-isocyanatopropyl)sulfide, 1,7-diisocyanatoheptane, 1,5-diisocyanato-2,2-dimethylpentane, 1,6-diisocyanate-3-methoxyhexane, 1,8-diisocyanatooctane, 1,5-diisocyanato-2,2,4-trimethylpentane, 1,9-diisocyanatononane, 1,10-diisocyanatopropyl ether of 1,4-butylene glycol, 1,11-diisocyanatoundecane, 1,12-diisocyanatododecane, bis(isocyanatohexyl) sulfide, 1,4-diisocyanatobenzene, 1,3-diisocyanato-o-xylene, 1,3-diisocyanato-p-xylene, 1,3-diisocyanate-m-xylene, 2,4-diisocyanato-1-chlorobenzene, 2,4-diisocyanato-1-nitrobenzene, 2,5-diisocyanato-1-nitrobenzene, m-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, mixtures of 2,4- and 2,6-toluene diisocyanate, 1,6-hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,4-cyclohexane diisocyanate, hexahydrotoluene diisocyanate, 1,5-naphthylene diisocyanate, 1-methoxy-2,4-phenylene diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenyl diisocyanate, 3,3'-dimethyl-4,4'-diphenylmethane diisocyanate and 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate; the triisocyanates such as 4,4',4"-triphenylmethane triisocyanate, polymethylene polyphenylene polyisocyanate and 2,4,6-toluene triisocyanate; and the tetraisocyanates such as 4,4'-dimethyl-2,2'-5,5'-diphenylmethane tetraisocyanate. Especially useful due to their availability and properties are toluene diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate and mixtures thereof.
The polyisocyanurate foams of the instant invention may be prepared by employing well-known compounds as trimerization catalysts. Examples of these catalysts are (a) organic strong bases, (b) tertiary amine co-catalyst combinations, (c) Friedel Craft catalysts, (d) basic salts of carboxylic acids, (e) alkali metal oxides, alkali metal alcoholates, alkali metal phenolates, alkali metal hydroxides and alkal metal carbonates (f) onium compounds from nitrogen, phosphorus, arsenic, antimony, sulfur and selenium, and (g) mono-substituted monocarbamic esters. These include 1,3,5-tris(N,N-dialkylaminoalkyl)-s-hexahydrotriazines; the alkylene oxide and water additives of 1,3,5-tris(N,N-dialkylaminoalkyl)-s-hexahydrotriazines; 2,4,6-tris(dimethylaminomethyl)phenol; ortho, para- or a mixture of o- and p-dimethylaminomethyl phenol and triethylenediamine or the alkylene oxide and water adducts thereof, metal carboxylates such as potassium octanoate, sodium and potassium salts of hydroxamic acid, and organic boron-containing compounds. Monofunctional alkanols containing from 1 to 24 carbon atoms, epoxides containing 2 to 18 carbon atoms and alkyl carbonates may be used in conjunction with tertiary amine to accelerate the rate of the polymerization reaction. The concentration of trimerization catalysts that may be employed in the present invention is from 0.001 part to 20 parts of catalyst per 100 parts of organic polyisocyanate. The temperature ranges which may be employed for the polymerization reaction may range from 25° C. to 230° C., preferably from 15° C. to 120° C.
In accordance with the present invention, rigid, flexible, and microcellular foams may be prepared by the catalytic reaction of organic polyisocyanates with polyols containing therein the etherified methylolmelamine in the presence of blowing agents, trimerization catalysts, surfactants and other additives which may be deemed necessary. Non-cellular products may also be prepared in the absence of blowing agents.
Typical optional polyols which may be employed in the preparation of the foams of the instant invention include polyhydroxyl-containing polyesters, polyoxyalkylene polyether polyols, polyhydroxy-terminated polyurethane polymers, polyhydroxyl-containing phosphorus compounds, and alkylene oxide adducts of polyhydric sulfur-containing esters, polyacetals, aliphatic polyols or diols, ammonia, and amines including aromatic, aliphatic and heterocyclic amines as well as mixtures thereof. Alkylene oxide adducts of compounds which contain two or more different groups within the above-defined classes may also be used such as amino alcohols which contain an amino group and a hydroxyl group. Also, alkylene oxide adducts of compounds which contain one --SH group and one --OH group as well as those which contain an amino group and a --SH group may be used. Generally, the equivalent weight of the polyols will vary from 100 to 10,000, preferably from 1000 to 3000.
Any suitable hydroxy-terminated polyester may be used such as are obtained, for example, from the reaction of polycarboxylic acids and polyhydric alcohols. Any suitable polycarboxylic acid may be used such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, brassylic acid, thapsic acid, maleic acid, fumaric acid, glutaconic acid, α-hydromuconic acid, β-butyl-α-ethyl-glutaric acid, α,β-diethylsuccinic acid, isophthalic acid, terephthalic acid, hemimellitic acid, and 1,4-cyclohexanedicarboxylic acid. Any suitable polyhydric alcohol may be used such as ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, glycerol, 1,1,1-trimethylolpropane, 1,1,1-trimethylolethane, 1,2,6-hexanetriol, α-methyl glucoside, pentaerythritol, and sorbitol. Also included within the term "polyhydric alcohol" are compounds derived from phenol such as 2,2-bis(4-hydroxyphenyl)propane, commonly known as Bisphenol A.
Any suitable polyoxyalkylene polyether polyol may be used such as the polymerization product of an alkylene oxide with a polyhydric alcohol. Any suitable polyhydric alcohol may be used such as those disclosed above for use in the preparation of the hydroxy-terminated polyesters. Any suitable alkylene oxide may be used such as ethylene oxide, propylene oxide, butylene oxide, amylene oxide, and mixtures of these oxides. The polyalkylene polyether polyols may be prepared from other starting materials such as tetrahydrofuran and alkylene oxide-tetrahydrofuran mixtures; epihalohydrins such as epichlorohydrin; as well as aralkylene oxides such as styrene oxide. The polyalkylene polyether polyols may have either primary or secondary hydroxyl groups. Included among the polyether polyols are polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol, polytetramethylene glycol, block copolymers, for example, combinations of polyoxypropylene and polyoxyethylene glycols, poly-1,2-oxybutylene and polyoxyethylene glycols, poly-1,4-tetramethylene and polyoxyethylene glycols, and copolymer glycols prepared from blends as well as sequential addition of two or more alkylene oxides. The polyalkylene polyether polyols may be prepared by any known process such as, for example, the process disclosed by Wurtz in 1859 and Encyclopedia of Chemical Technology, Vol. 7, pp. 257-262, published by Interscience Publishers, Inc. (1951) or in U.S. Pat. No. 1,922,459. Polyethers which are preferred include the alkylene oxide addition products of trimethylolpropane, glycerine, pentaerythritol, sucrose, sorbitol, propylene glycol, and 2,2-bis(4-hydroxyphenyl)propane and blends thereof having equivalent weights of from 100 to 5000.
Suitable polyhydric polythioethers which may be condensed with alkylene oxides include the condensation product of thiodiglycol or the reaction product of a dicarboxylic acid such as is disclosed above for the preparation of the hydroxyl-containing poyesters with any other suitable thioether glycol.
The hydroxyl-containing polyester may also be a polyester amide such as is obtained by including some amine or amino alcohol in the reactants for the preparation of the polyesters. Thus, polyester amides may be obtained by condensing an amino alcohol such as ethanolamine with the polycarboxylic acids set forth above or they may be made using the same components that make up the hydroxyl-containing polyester with only a portion of the components being a diamine such as ethylene diamine.
Polyhydroxyl-containing phosphorus compounds which may be used include those compounds disclosed in U.S. Pat. No. 3,639,542. Preferred polyhydroxyl-containing phosphorus compounds are prepared from alkylene oxides and acids of phosphorus having a P 2 O 5 equivalency of from about 72 percent to about 95 percent.
Suitable polyacetals which may be condensed with alkylene oxides include the reaction product of formaldehyde or other suitable aldehyde with a dihydric alcohol or an alkylene oxide such as those disclosed above.
Suitable aliphatic thiols which may be condensed with alkylene oxides include alkanethiols containing at least two --SH groups such as 1,2-ethanedithiol, 1,2-propanedithiol, 1,2-propanedithiol, and 1,6-hexanedithiol; alkene thiols such as 2-butene-1,4-dithiol; and alkyne thiols such as 3-hexyne-1,6-dithiol.
Suitable amines which may be condensed with alkylene oxides include aromatic amines such as aniline, o-chloroaniline, p-aminoaniline, 1,5-diaminonaphthalene, methylene dianiline, the condensation products of aniline and formaldehyde, and diaminotoluene; aliphatic amines such as methylamine, triisopropanolamine, ethylene diamine, 1,3-diaminopropane, 1,3-diaminobutane, and 1,4-diaminobutane.
Water, low boiling hydrocarbons such as pentane, hexane, heptane, pentene, and heptene; azo compounds such as azohexahydrobenzodinitrile; halogenated hydrocarbons such as dichlorodifluoromethane, trichlorofluoromethane, dichlorodifluoroethane, vinylidene chloride, and methylene chloride may be used as blowing agents.
Chain-extending agents which may be employed in the preparation of the polyurethane foams include those compounds having at least two functional groups bearing active hydrogen atoms such as water, hydrazine, primary and secondary diamines, amino alcohols, amino acids, hydroxy acids, glycols, or mixtures thereof. A preferred group of chain-extending agents includes water, ethylene glycol, 1,4-butanediol, and primary and secondary diamines which react more readily with the polyisocyanates than does water. These include phenylenediamine, ethylenediamine, diethylenetriamine, N-(2-hydroxypropyl)-ethylenediamine, N,N'-di(2-hydroxypropyl)ethylenediamine, piperazine, and 2-methylpiperazine.
A surface-active agent is generally necessary for production of high grade polyurethane foam according to the present invention, since in the absence of same, the foams collapse or contain very large uneven cells. Numerous surface-active agents have been found satisfactory. Nonionic surface-active agents are preferred. Of these, the nonionic surface-active agents such as the well-known silicones have been found particularly desirable. Other surface-active agents which are operative, although not preferred, include polyethylene glycol ethers of long chain alcohols, tertiary amine or alkanolamine salts of long chain alkyl acid sulfate esters, alkyl sulfonic esters, and alkyl arylsulfonic acids.
In the following examples, all parts are by weight unless otherwise designated and the following abbreviations are employed.
Etherifying agent
A--butanol
B--methanol
C--dibromopropanol
D--trichloroethanol
E--2-ethoxyethanol
F--furfuryl alcohol
G--allyl alcohol
H--2-chloroethanol
I--diethylene glycol
J--diethanolamine
K--diethylphosphite
L--N-methylethanolamine
Polyol A--a propylene oxide adduct of pentaerythritol having a hydroxyl number of 400.
Freon 11A--monochlorotrifluoromethane sold by E. I. duPont de Nemours & Co.
L-5303--a silicone surfactant
TDH--1,3,5-tris(N,N-dimethylaminopropyl)-S-hexahydrotriazine
T-9--stannous 2-ethylhexanoate
EXAMPLES 1-12
Into a suitable reaction vessel equipped with a stirrer, reflux condenser, and thermometer was added formaldehyde, melamine, neutralized formalin solution and one-half of the etherifying agent or mixtures thereof in the amounts indicated in the Table below. The amount of sodium hydroxide varied from 0.75 pbw to 2.0 pbw. The mixture was heated to about 55° C. for two hours. After cooling, the remaining amount of etherifying agent was added and the mixture was heated to 35° C. The alkaline catalyst was neutralized with nitric acid, the reaction solution was then vacuum stripped at 50° C. to remove all volatiles. The residue was then washed with methylene chloride, filtered, and the product obtained by vacuum stripping the volatiles at 50° C.
TABLE I______________________________________ Melamine, Formaldehyde, EtherifyingExample pbw pbw agent, pbw OH No.______________________________________1 126 567 A, 370 2082 126 312 B, 480 234.63 63 156 B, 122 75.1 C, 8284 63 156 B, 122 350 D, 5005 126 312 E, 1210 223.96 126 568 F, 686 414.37 315 780 G, 1885 2788 126 312 H, 1077 3829 126 312 B, 448 511 I, 10610 126 312 B, 480 727 J, 005 K, 13811 126 312 B, 320 546 L, 225 K, 27812 315 780 B, 1200 380______________________________________
EXAMPLES 13-24
The designated resin, with or without added Polyol A (300 pbw), 9.0 pbw Freon 11A, 4 parts L-5303, 2.1 parts TDH catalyst and 0.1 parts of T-9 catalyst were mixed for 30 seconds. Crude MDI was added, the mixture was stirred for 10 seconds and the entire mixture poured into a one-gallon container and the foam was allowed to rise. The resulting foams were cured at room temperature for 25 hours. The resins employed and the resulting physical properties of the foams are shown in Table II below. Improvements in smoke density, friability and weight retained in the Butler chimney test are shown when the resins of the invention are employed.
TABLE II__________________________________________________________________________Example 13 14 15 16 17 18 19 20 21 22 23 24__________________________________________________________________________Resin of Example -- 2 12 -- 2 4 5 5 -- 1 2 5Polyol A A -- A A A A -- A A A --Resin/polyol ratio -- 1:1 -- -- 1:1 10:1 1:1 -- -- 1:1 1:1 1Isocyanate Index 200 200 200 300 300 300 300 300 400 400 400 400PropertiesCore Density, pcf 2.34 2.07 1.51 2.29 1.65 1.52 1.95 2.14 2.39 1.87 1.67 2.03Compressive strength, 31.4 21.2 12.4 29.2 19.8 17.0 22.0 23.6 31.3 20.5 18.9 19.8psi; 10% deflFriability, % wt. loss 11.3 46.1 85.3 21.1 61.6 67.3 57.6 51.6 23.6 68.6 66.1 62.5Closed cells, %Uncorrected 88.4 87.0 82.5 87.7 87.2 89.3 84.5 85.9 87.2 83.9 85.4 83.5Corrected 95.1 95.0 96.3 95.6 96.6 102.0 94.3 101.7 96.2 95.2 93.7 102.8K-factor .120 .126 .144 .120 .148 .150 .140 .160 .125 .150 .151 .161Flammability TestsNBS Smoke Density, Dm 147 60 32 128 51 57 61 35 113 55 43 37Oxygen Index, % O.sub.2 19.94 19.74 22.65 20.93 21.12 21.89 20.73 20.93 21.51 22.65 21.89 21.89Butler Chimney% wt. retained 25.8 44.6 80.7 53.8 57.1 54.8 56.2 78.5 73.5 56.4 67.5 84.9Time to SX, sec. 38 27 10 19 17 17 21 10 12 16 14 10Flame ht., cm. 25 25 25 25 25 25 25 25 25 25 25 25__________________________________________________________________________ | Polyisocyanurate foams are prepared from reacting partially etherified methylolmelamines either alone or in mixture with polyoxyalkylene polyether polyols with polyisocyanates. Improved friability and flame retardancy are obtained. | 2 |
This is a division of application Ser. No. 671,423, filed on Mar. 29, 1976.
BACKGROUND OF THE INVENTION
1. Field of the Invention
Compounds of this invention are analogues of natural prostaglandins.
Natural prostaglandins are twenty-carbon atom alicyclic compounds related to prostanoic acid which has the following structure: ##STR2## By convention, the carbon atoms of A are numbered sequentially from the carboxylic carbon atom. An important stereo-chemical feature of A is the trans-orientation of the side-chains C 1 -C 7 and C 13 -C 20 . All natural prostaglandins have this orientation. In A, as elsewhere in this specification, a dashed line (----) indicates projection of a covalent bond below the plane of a reference carbon atom or ring (alpha-configuration), while a wedged line represents direction above that plane (beta-configuration). Those conventions apply to all compounds subsequently discussed in this specification.
In one system of nomenclature suggested by N. A. Nelson (J. Med. Chem., 17: 911 (1972)!, prostaglandins are named as derivatives or modifications of the natural prostaglandins. In a second system, the I.U.P.A.C. (International Union of Pure and Applied Chemistry) system of nomenclature, prostaglandins are named as substituted heptanoic acids. Yet a third system of nomenclature is frequently used by those skilled in the prostaglandin art. In this third system (also described by Nelson), all prostaglandins are named as derivatives or modifications of prostanoic acid (structure A) or prostane (the hydrocarbon equivalent of structure A). This system is used by Chemical Abstracts and may become an I.U.P.A.C. accepted system.
Natural prostaglandins have the structures, ##STR3## in which: L and M may be ethylene or cis-vinylene radicals and the five-membered ring ##STR4##
Prostaglandins are classified according to the functional groups present in the five-membered ring and the presence of double bonds in the ring or chains. Prostaglandins of the A-class (PGA or prostaglandin A) are characterized by an oxo group at C 9 and a double bond at C 10 -C 11 (Δ 10 ,11); those of the B-class (PGB) have an oxo group at C 9 and a double bond at C 8 -C 12 (Δ 11 ,12); compounds of the C-class (PGC) contain an oxo group at C 9 and a double bond at C 11 -C 12 (Δ 11 ,12); members of the D-class (PGD) have an oxo group at C 11 and an alpha-oriented hydroxy group at C 9 ; prostaglandins of the E-class (PGE) have an oxo group at C 9 and an alpha-oriented hydroxyl group at C 11 ; and members of the F-class (PGF) have an alpha-directed hydroxyl group at C 9 and an alpha-oriented hydroxyl group at C 11 . Within each of the A, B, C, D, E, and F classes of prostaglandins are three subclassifications based upon the presence of double bonds in the side-chains at C 5 -C 6 , C 13 -C 14 , or C 17 -C 18 . The presence of a trans-unsaturated bond only at C 13 -C 14 is indicated by the subscript numeral 1; thus, for example, PGE 1 (or prostaglandin E 1 ) denotes a prostaglandin of the E-type (oxo group at C 9 and an alpha-hydroxyl at C 11 ) with a trans-double bond at C 13 -C 14 . The presence of both a trans-double bond at C 13 -C 14 and a cis-double bond at C 5 -C 6 is denoted by the subscript numeral 2; for example, PGE 2 . Lastly, a trans-double bond at C 13 -C 14 , a cis-double bond at C 5 -C 6 and a cis-double bond at C 17 -C 18 is indicated by the subscript numeral 3; for example, PGE 3 . The above notations apply to prostaglandins of the A, B, C, D, and F series as well, however, in the latter the alpha-orientation of the hydroxyl group at C 9 is indicated by the subscript Greek letter α after the numerical subscript.
The three systems of nomenclature as they apply to natural PGF 3 α are shown below: ##STR5## Nelson System:
Prostaglandin F 3 α or PGF 3 α (shortened form) I.U.P.A.C. System:
7- 3R, 5S-Dihydroxy-2R-(3S-hydroxy-1E,5Z-octadienyl)-cyclopent-1R-yl!-5Z-heptenoic acid Third System (Chemical Abstracts):
(5Z, 9α, 11α, 13E, 15S, 17Z)-9,11,15-trihydroxyprosta-5,13,17-trien-1-oic acid.
It is important to note that in all natural known prostaglandins there is an alpha-oriented hydroxyl group at C 15 . In the Cahn-Ingold-Prelog system of defining stereochemistry, that C 15 hydroxyl group is in the S-configuration. The Cahn-Ingold-Prelog system is used to define stereochemistry of any asymmetric center outside of the carbocyclic ring in all three systems of nomenclature described above. This is in contrast to some prostaglandin literature in which the α,β designations are used, even at C 15 .
11-Deoxy derivatives of PGE and PGF molecules have not yet been found to occur as such in nature, but constitute a class of compounds which possess biological activity related to the parent compounds. Formula B represents 11-deoxy PGE and PGF compounds when: ##STR6## In this formula, and others of this patent specification a swung dash or serpentine line (˜) denotes a covalent bond which can be either in the alpha configuration (projecting below the plane of a reference carbon atom or ring) or in the beta configuration (projecting above the plane of a reference carbon atom or ring).
PGF.sub.β molecules also do not occur as such in nature, but constitute a class of compounds which possess biological activity related to the parent compounds. Formula B represents PGF.sub.β compounds when: ##STR7##
9-Deoxy derivatives of PGE do not occur as such in nature, but constitute a class of compounds which possess biological activity related to the parent compounds. Formula B represents 9-deoxy PGE compounds when: ##STR8##
9-Deoxy-Δ 9 ,10 derivatives of PGE have not been found to occur as such in nature, but constitute a class of compounds which possess biological activity related to the parent compounds. Formula B represents 9-deoxy-Δ 9 ,10 PGE compounds when: ##STR9##
9a-homo- and 9a-homo-11-deoxy-molecules have not been found to occur as such in nature, but constitute a class of compounds which possess biological activity related to the parent compounds. Formula B represents 9α-homo- and 9α-homo-11-deoxy-compounds of PGE and PGF when: ##STR10##
11a-Homo- derivatives of PGE, PGF and PGA molecules do not occur as such in nature, but constitute classes of compounds which are expected to possess biological activity related to the parent compounds. Formula B represents 11a-homo- derivatives of PGE, PGF and PGA molecules when: ##STR11##
11-Epi-PGE and PGF molecules do not occur as such in nature, but constitute classes of compounds which possess biological activity related to the parent compounds. Formula B represents 11-epi-compounds of PGE and PGF when: ##STR12##
8Iso-, 12iso or 8,12-bis iso (ent) prostaglandins do not occur as such in nature, but constitute classes of compounds which possess biological activity related to the parent compounds. Formula B represents 8iso-, 12iso or 8,12-bis iso (ent) compounds when: ##STR13## These iso modifications of Formula B may be divided into all of the sub-classes with varying ring oxygenation as described above.
Recent research indicates that prostaglandins are ubiquitous in animal tissues and that prostaglandins, as well as their synthetic analogues, have important biochemical and physiological effects in mammalian endocrine, reproductive, central and peripheral nervous, sensory, gastro-intestinal, hematic, respiratory, cardiovascular, and renal systems.
In mammalian endocrine systems, experimental evidence indicates prostaglandins are involved in the control of hormone synthesis or release in hormone-secretory glands. In rats, for example, PGE 1 and PGE 2 increase release of growth hormone while PGA 1 increased synthesis of that hormone. In sheep, PGE 1 and PGF 1 α inhibit ovarian progesterone secretion. In a variety of mammals, PGF 1 α and PGF 2 α act as luteolytic factors. In mice, PGE 1 , PGE 2 , PGF 1 α and PGF 1 β increase thyroid activity. In hypophysectimized rats, PGE 1 , PGE 2 and PGF 1 α stimulate steriodogenesis in the adrenal glands.
In the mammalian male reproductive system, PGE 1 contracts the smooth muscle of the vas deferens. In the female reproductive system, PGE and PGF.sub.α compounds contract uterine smooth muscle. In general, PGE, PGB and PGA compounds relax in vitro human uterine muscle strips, while those of the PGF.sub.α class contract such isolated preparations. PGE compounds in general promote fertility in the female reproductive system while PGF 2 α has contragestational effects. PGF 2 α also appears to be involved in the mechanism of menstruation. In general, PGE 2 exerts potent oxytocic effects in inducing labor, while PGF 2 α induces spontaneous abortions in early pregnancy.
PGF.sub.α and PGE compounds have been isolated from a variety of nervous tissue and they seem to act as neurotransmitters. PGE 1 retards whereas PGF 2 α facilitates transmission in motor pathways in the central nervous system. It has been reported that PGE 1 and PGE 2 inhibit transmitter release from adrenergic nervie endings in the guinea pig.
Prostaglandins stimulate contraction of gastrointestinal smooth muscle in vivo and in vitro. In dogs, PGA 1 , PGE 1 and PGE 2 inhibit gastric secretion. PGA 1 exhibits similar activity in man.
In most mammalian respiratory tracts, compounds of the PGE and PGF class relax in vitro preparations of tracheal smooth muscle. In that preparation, PGE 1 and PGE 2 relax while PGF 2 α contracts the smooth muscle. PGE and PGF compounds are normally found in the human lung, and it is postulated that some cases of bronchial asthma involve an imbalance in the production or metabolism of those compounds.
Prostaglandins are involved in certain hematic mechanisms in mammals. PGE 1 , for example, inhibits thrombogenesis in vitro through its effects on blood platelets.
In a variety of mammalian cardiovascular systems, compounds of the PGE and PGA class are vasodilators whereas those of the PGF.sub.α class are vasoconstrictors, by virtue of their action on vascular smooth muscle.
Prostaglandins are naturally found in the kidney and reverse experimental and clinical renoprival hypertension. The clinical implications of prostaglandins and their analogues are far-ranging and include, but are not limited to the following: in obstetrics and gynecology, they may be useful in fertility control, treatment of menstrual disorders, induction of labor, and correction of hormone disorders; in gastroenterology, they may be useful in the treatment of peptic ulcers and various disorders involving motility, secretion, and absorption in the gastrointestinal tract; in the respiratory areas, they may be beneficial in therapy of bronchial asthma and other diseases involving bronchoconstriction; in hematology, they may have utility as anti-clotting agents in diseases such as venous thrombosis, thrombotic coronary occlusion and other diseases involving thrombi; in circulatory diseases they have therapeutic utility in hypertension, peripheral vasopathies, and cardiac disorders.
SUMMARY
The present invention relates to prostaglandin analogues having the structural formula, ##STR14## in which: T is selected from the group consisting of carboxyl, alkoxycarbonyl or cyano;
M is selected from the group consisting of carbonyl, R-hydroxymethylene or S-hydroxymethylene;
L is selected from the group consisting of methylene or methine, provided L is methine only if J is methine;
J is selected from the group consisting of methylene, ethylene, R-hydroxymethylene, S-hydroxymethylene or methine, provided J is methine only if L is methine;
W is selected from the group consisting of --CH 2 --CH-- or trans--CH═C--;
T 1 and T 2 are attached to adjacent carbon atoms;
T 1 is selected from the group consisting of hydrogen or phenyl, provided T 1 is phenyl only if T 2 is lower alkyl;
T 2 is selected from the group consisting of n-pentyl or lower alkyl, provided T 2 is lower alkyl only if T 1 is phenyl;
or T 1 and T 2 are joined together to form an alkylene group of 4 or 6 carbon atoms.
As employed with reference to the compounds of the invention, the term, "alkoxycarbonyl" (at times referred to as "COOAlk") shall mean and include groups of the formula ##STR15## wherein n is from 0 to 2 inclusive. Note that, following conventionally established numerical designation for natural prostaglandins, where T is a carboxy, cyano or carbinol group, the carbon atom in such group is the first-numbered. Where T is an alkoxycarbonyl group, the carbon atom of the oxo radical is designated the first (i.e., numbered "1") carbon atom of the structure.
As employed herein, "lower alkyl" (at times referred to as "1-alk") shall mean and include aliphatic groups having from 1 to 3 carbon atoms.
Note that the condition, "T 1 and T 2 are attached to adjacent carbon atoms" specifies that T 1 is invariably attached on the carbon atom corresponding to "C 14 " of the parent compounds whether W is --CH 2 --CH-- or trans --CH═C--.
A structural feature common to all of the compounds of the invention is the replacement of the C 5 -C 6 portion of the natural prostaglandins and/or derivatives thereof by an o-phenylene group.
Comprehended by the present invention are certain preferred 11-deoxy compounds wherein, if L and J are both methylene, then: either T is alkoxycarbonyl or, preferably, cyano; or W is --CH 2 --CH--; or T 1 is phenyl; or T 1 and T 2 are joined together to form an alkylene group of 4 or 6 carbon atoms.
Comprehended by the present invention are preferred compounds of subgeneric structures representing analogues of the A-, E-, and F-series or classes of the prostaglandins and/or derivatives thereof. Thus when M is carbonyl, compounds of the invention have a formula generally characteristic of both the A- and E-classes of prostaglandins: ##STR16##
Where M is carbonyl, L is methylene or methine and J is R-hydroxymethylene, S-hydroxymethylene or ethylene, compounds of the invention are analogues of the A- and/or E-classes of prostaglandins and may include the 11 deoxy and/or 9a-homo derivatives thereof. More particularly, where M is carbonyl, L is methylene and J is ethylene compounds of the invention are 11 deoxy-9a-homo- analogues of the E-class having the formula: ##STR17## Where M is carbonyl, L is methylene, and J is methylene, compounds of the invention are 11-deoxy analogues of the E-class having the formula: ##STR18## Where M is carbonyl, L is methylene and J is R-hydroxymethylene or S-hydroxymethylene, compounds of the invention are E-class analogues having the formula: Where M is carbonyl, L is methine and J is methine, compounds of the invention are A-class analogues having the formula: ##STR19##
Where, however, M is R-hydroxymethylene or S-hydroxymethylene, L is methylene and J is R-hydroxymethylene or S-hydroxymethylene, compounds of the invention are F-class analogues having the formula: ##STR20##
Preparation of the compounds of the present invention and having the structures Ib, Ic, Id, Ie, If, generally proceeds by the 1,4-conjugate addition of organocopper reagents to certain ketones as reported by Sih, et al. J. Amer. Chem. Soc., 97; 857, 865 (1975) and references cited therein!. Specifically, compounds having the structure Ib are prepared in the manner outlined in Table A from certain ketones IV (themselves prepared from the doines II, the synthesis of which is outlined in Table D) and certain lithium cuprates V (prepared in the manner outlined in Table E). Preparation of certain halovinyl alcohols XXII necessary for preparation of some cuprates useful in the practice of the invention is outlined in Table F. Preparation of compounds having the structure Ic from the ketones IX (again, prepared from the diones II) is outlined in Table B. Preparation of compounds of the invention having the structures Id, Ie and If from certain ketones XVI (the preparation of which is outlined in Table G) is outlined in Table C.
TABLE A______________________________________SYNTHETIC PATHWAY FOR PREPARATIONOF COMPOUNDS OF STRUCTURE Ib______________________________________ ##STR21## ##STR22## ##STR23##______________________________________a .... T = CNb .... T = COOAlkc .... T = COOHQ.sub.1 = n-C.sub.3 H.sub.7 ##STR24##
TABLE B______________________________________SYNTHETIC PATHWAY FOR PREPARATIONOF COMPOUNDS OF STRUCTURE Ic______________________________________ ##STR25## ##STR26## ##STR27##______________________________________a .... T = CNb .... T = COOAlkc .... T = COOHQ.sub.1 = n-C.sub.3 H.sub.7 ##STR28##
TABLE C__________________________________________________________________________SYNTHETIC PATHWAY FOR PREPARATION OF STRUCTURES Id, Ie, AND__________________________________________________________________________If ##STR29## ##STR30## ##STR31##__________________________________________________________________________a .... T = COOCH.sub.3b .... T = COOC.sub.2 H.sub.5c .... T = COOHQ.sub.1 = n-C.sub.3 H.sub.7 ##STR32##XIX = Ie; XVII = Id and XVIII = If where W is trans CHC;XX = Id and XXI is If where W is CH.sub.2CH
In Table A, a selected 2-substituted benzyl-1,3-cyclohexanedione II (see, Table D) is converted to the enol sulfonate III (Ar = mesityl) with 2-mesitylenesulfonyl chloride. These sulfonates are not usually isolated but are reduced directly with sodium borohydride to give, after hydrolysis, the unsaturated ketone IV. These unsaturated ketones are reacted with selected lithium cuprates V see, House, et al., Org. Chem. 38; 3893 (1973); Corey, et al., J. Amer. Chem. Soc. 94: 7210 (1972); and Tables E and F! to give, after hydrolysis, the compounds Ib either as the 11-deoxy-9-a-homo-E 1 series analogue VI (wherein W is trans -CH═C-) or, upon hydrogenation, the 13,14-dihydro-11-deoxy-9-a-homo-E 1 series analogue VII (wherein W is --CH 2 --CH--).
In Table B, a selected dione II is converted to the chlorodione VIII which can be rearranged to the unsaturated ketones IX Buchi, et al., J. Org. Chem. 36: 2021 (1971)!. The reaction of these with lithium cuprate complexes V produces, after hydrolysis, the compounds Ic either as the 11-deoxy-E 1 series analogue X or, upon hydrogenation, the dihydro-11-deoxy-E 1 series analogue XI.
In Table C, a selected ketone XV (see Table G), upon protection of the hydroxy function as in XVI, is reacted with lithium cuprate to form, upon hydrolysis, the compounds Id either as the E 1 -series analogue XVII or, upon hydrogenation, the dihydro-E 1 series analogue XX. Reduction of the ketone function in XVII leads to compounds of If, either as the F 1 -series analogue XVIII or, upon hydrogenation, the dihydro-F 1 -series analogue XXI. The dehydration of compounds XVII to give compounds Ie , is represented by XIX.
TABLE D__________________________________________________________________________SYNTHETIC PATHWAY FOR PREPARATION OF CERTAINDIONES FOR USE IN PREPARING COMPOUNDSOF STRUCTURES Ib AND Ic__________________________________________________________________________ ##STR33## ##STR34## ##STR35## ##STR36##__________________________________________________________________________ a. . .T = CN b. . .T = COOAlk c. . .T = COOH
TABLE E______________________________________SYNTHETIC PATHWAY FOR PREPARETIONOF CERTAIN LITHIUM CUPRATES______________________________________ ##STR37## XXII ##STR38## XXIII ##STR39## XXIV ##STR40## V a. . .X = I, T.sub.1 = C.sub.6 H.sub.5, and T.sub.2 = 1-alk b. . .X = I, T.sub.1 and T.sub.2 = c. . .X = Br, T.sub.1 and T.sub.2 = (CH.sub.2).sub.6- d. . .X = I, T.sub.1 = H, T.sub.2 = n-C.sub.5 H.sub.11
TABLE F______________________________________SYNTHETIC PATHWAY FOR PREPARATIONOF CERTAIN IODOVINYL ALCOHOLS______________________________________ ##STR41## XXVI ##STR42## XXVII ##STR43## XXVIII ##STR44## XXIX ##STR45## XXX ##STR46## XXXI ##STR47## XXII______________________________________ a. . .X = I, T.sub.1 = C.sub.6 H.sub.5, and T.sub.2 = 1-alk b. . .X = I, T.sub.1 and T.sub.2 = c. . .X = Br, T.sub.1 and T.sub.2 = d. . .X = I, T.sub.1 = H, T.sub.2 = n-C.sub.5 H.sub.11
Table D illustrates preparation of the diones II for use in the preparations of Tables A and B. Compound 1 1,3-cyclohexanedione is alkylated with 2-(3-chloropropyl)-benzyl chloride 2 Page, et al., J. Amer. Chem. Soc. 75: 2053 (1953)! to give the dione 3. The displacement of the chloro group by cyanide ion gives the cyanodione IIa. The latter may be carried on through the synthesis of Table A or hydrolyzed with mineral acid to the keto diacid 4 which may be converted to the diester 5. Subsequently the diester 5 can be cyclized to produce the dione ester IIb which in turn can be converted to the acid IIc.
Table E illustrates formation of lithium cuprates V through reaction of resolved iodovinyl alcohols XXII with ethylvinyl ether to give mixed acetals XXIII which, in turn react with t-butyl lithium to yield the lithio derivative XXIV. Treatment of XXIV with copper n-propylacetylide complexed with hexamethylphosphorous triamide gives the lithium cuprate reagent.
Table F illustrates preparation of certain halovinyl alcohols XXII wherein the apropriate ketone XXVI is treated with ethyl formate under basic conditions to give formyl ketones XXVII. These react with p-toluenesulfonyl chloride in the presence of tertiary amines to produce the enol tosylates XXVIII. When reacted with sodium or potassium halides, the enol tosylates give the β-halovinyl ketones XXIX which are not usually purified but reduced directly with sodium borohydride to racemic alcohols XXX. The optical resolution of the alcohols is accomplished by converting them to phthalate esters XXXI. These acids are reacted with L-(-)-α-methyl benzylamine to give the diastereomeric amine salts Kluge, et al., J. Amer. Chem. Soc. 94: 7827 (1972)!.
TABLE G__________________________________________________________________________SYNTHETIC PATHWAY FOR PREPARATION OF CERTAIN KETONES FOR USE INPREPARINGCOMPOUNDS OF STRUCTURES Id, Ie AND If ##STR48## ##STR49## ##STR50## ##STR51## ##STR52## ##STR53## ##STR54## ##STR55##__________________________________________________________________________ a. . .T = COOCH.sub.3 - b. . .T = COOC.sub.2 H.sub.5 - c. . .T = COOH
Several recrystallizations gives the resolved salts which regenerate the optically pure alcohols XXII on hydrolysis with concentrated sodium hydroxide. Both the β-halovinyl alcohols XXII and the ketones XV possess free hydroxyl groups that must be protected during the reaction with the lithium cuprate reagents V by converting them to the ethyl vinyl ether adducts XXIII and XVI before use.
Table G illustrates preparation of certain ketones for use in the synthesis of Table C beginning with alkylation of 2,4-pentane dione 6 with 2 to yield the chloroketone 7 Boatman, et al., J. Org. Chem. 30: 3321 (1965)!. Treatment of the latter with cyanide ion gives the cyano ketone 8 which is hydrolyzed to the keto acid 9 and esterified to the keto ester 10. Condensation of 10 with two equivalents of diethyl oxalate under basic conditions Katsube, et al., Agr. Biol. Chem. 33: 1078 (1969)! gives, after hydrolysis, the trione acid 11. Esterification of 11 with methanol or ethanol gives the esters XII. Reduction of 11 leads to the hydroxydione XIII. Treatment of XIII with 2-mesitylene sulfonyl chloride gives the enol sulfonate XIV which is not isolated but reduced to the unsaturated ketone XV.
Briefly stated, the following are among the methods of the present invention.
1. Forming an 11-deoxy-9-a-homo-E 1 series prostaglandin analogue of Formula Ib by: (a) preparing a selected 2-substituted benzyl-1,3-cyclohexane dione II; (b) forming the unsaturated ketone IV from II via the enol sulfonate III; and (c) reacting the ketone IV with a selected lithium cuprate V to form the desired product VI which may be hydrogenated to the 13,14-dihydro-form VII. 2. Forming an 11-deoxy-9-a-homo-E 1 prostaglandin analogue of Formula Ic by: (a) converting the dione II to the chlorodione VIII; (b) rearranging the chlorodione VIII to the unsaturated ketone IX; and (c) reacting the ketone IX with a selected lithium cuprate V to form the desired product X which may be hydrogenated to the dihydro form XI.
3. Forming an E 1 prostaglandin analogue of Formula Id by: (a) preparing an unsaturated ketone XV (from the intermediates XII, XIII and XIV prepared from 2-(3-chloro propyl)-benzyl chloride 2 and 2,4-pentane dione 6via the compounds 7, 8, 9, 10 and 11); and (b) reacting the ketone XV with a selected lithium cuprate V to form the desired product XVII which may be hydrogenated to dihydro form XX.
4. Forming an F 1 -prostaglandin analogue of Formula Ie by reducing the ketone function of the E 1 -series analogue XVII to form the desired product XVIII which may be hydrogenated to the dihydro form XXI.
5. Forming an A 1 -prostaglandin analogue of Formula If through dehydration of the E 1 -series analogue XVII to form the desired product XIX.
Specific reaction parameters and variations of the syntheses outlined in Tables A-G will become apparent upon consideration of the following detailed description thereof.
As one example, the unsaturated ketones XV and the halovinyl alcohols XXII possess a free hydroxyl group that must be protected during the reaction with the lithium cuprate complex V. This is done by converting them to the mixed acetals XVI and XXIII by reaction with ethyl vinyl ether just prior to reaction Kluge, et al., J. Amer. Chem. Soc. 94:7827 (1972); Sih, et al., J. Amer. Chem. Soc. 94:3643 (1972)!. These are isolated and used directly.
As another example, as indicated in Tables A, B and C, the reaction of the lithium cuprate complexes V derived from an optically active alcohol, XXII, with the ketones IV, IX, and XVI produces, in each case, two isomers: the so-called 15-epi-enantimomeric isomer with the stereochemistry depicted in XXXII and the natural isomer depicted in XXXIII. These can usually be separated by column chromatography. ##STR56##
The 15-epi-enantomeric isomer (ent) is commonly less polar than the natural isomer (nat) and hence is eluted off the column first.
DETAILED DESCRIPTION
The following Examples 1-20 relate to preparation of certain intermediates involved in preparation of compounds of the structure I.
EXAMPLE 1
2- 2-(3-Chloropropyl)benzyl!-1,3-cyclohexanedione, 3. --
A solution of 155 g (0.75 mol) of 2-(3-chloropropyl)benzyl chloride 2 Page, et al., J. Amer. Chem. Soc. 75:2053 (1953)!, 91 g (0.81 mol) of 1,3-cyclohexanedione 1 Aldrich Chem. Co. 10,160-5; Beilstein 7, 554!, and 47 g of 85% KOH in 400 ml of methanol was refluxed 16 hours. After concentrating, the residue was partitioned between benzene and dilute aqueous NaOH solution. Acidification of the aqueous phase gave a solid that was recrystallized from ethyl acetate to give 34 g of the dione 3, mp 143-145° C.
Analysis, Calc'd. for C 16 H 19 ClO 2 : C,68.93; H, 6.87 Found: C, 69.66; H, 7.21
EXAMPLE 2
2- 2-(3-Cyanopropyl)benzyl!-1,3-cyclohexanedione, IIa. --
A mixture of 22 g (0.079 mol) of 2- 2-(3-chloropropyl) benzyl !- 1,3-cyclohexanedione 3 and 15.5 g (0.316 mol) of NaCN in 250 ml of dry dimethyl sulfoxide was stirred at 95 ° C for 3 hours. The reaction was filtered while hot to remove NaCl, and the dimethyl sulfoxide was distilled out under high vacuum. The residue was dissolved in 400 ml H 2 O, filtered through a diatomaceous earth filter aid (celite) to give a red solution and neutralized by the rapid addition of 40 ml concentrated HCl. The precipitate was recrystallized twice from ethyl acetate to give 16 g of the cyanodione, IIa, mp 143° C.
Analysis, Calc'd. for C 16 H 19 NO 2 : C, 75.81; H, 7.11; N, 5.20 Found: C, 76.97; H, 7.39; N, 4.86
EXAMPLE 3
5-keto-7- 2-(3-Carboxypropyl)benzyl!heptanoic Acid, 4. --
A solution of 32 g (0.12 mol) of 2- 2-(3--cyanopropyl)benzyl)benzyl!-1,3-cyclohexanedione IIa in 250 ml glacial acetic acid and 250 ml concentrated HCl was refluxed 16 hours. The solvent was evaporated and the residue recrystallized from H 2 O to give 30 g of the keto diacid 4, mp 87° C.
Analysis, Calc'd. for C 17 H 22 O 5 : C,66.65; H, 7.24 Found: C, 66.52; H, 7.50
EXAMPLE 4 Methyl 5-Keto-7- 2-(3-carbomethoxypropyl)benzyl!heptanoate, 5
A mixture of 30 g (0.1 mol) of 5-keto-7- 2-(3-carboxy propyl)benzyl)heptanoic acid, 4, 150 ml absolute methanol, and 26 g (0.2 mol) of boron trifluoride-methanol complex was refluxed for 2 hours. The solvent was evaporated to near dryness and the gummy residue taken up in 500 ml ether. After washing to neutrality with H 2 O and aqueous sodium bicarbonate, the ether solution was dried over anhydrous CaCl 2 and evaporated. This gave 29 g of the keto diester 5 as a pale amber oil. This was not further purified but was used directly to make the dione IIb.
EXAMPLE 5
2- 2-(3-Carbomethoxypropyl)benzyl!-1,3 -cyclohexanedione, IIb
The diester 5, 26.5 g (0.08 mol) was dissolved in a solution made by dissolving 1.84 g (0.09 g-atm) sodium in 200 ml absolute MeOH. The resulting solution was refluxed 9 hours. Evaporation gave a red, gummy residue that was partitioned between 300 ml H 2 O and 300 ml ether. Evaporation of the ether gave back 3 g of unreacted keto diester 5. The aqueous phase was acidified and the precipitate recrystallized from toluene to give 20 g of the dione ester IIb, mp 124°-125° C.
Analysis, Calc'd. for C 18 H 22 O 4 : C, 71.50; H, 7.33 Found: C, 71.31; H, 7.42
EXAMPLE 6
2- 2-(3-Cyanopropyl)benzyl!-2-cyclohexene-1-one, IVa
A solution of 39 g (0.145 mol) of 2- 2-(3-cyanopropyl)benzyl!1,3-cyclohexanedione IIa in 500 ml of dry tetrahydrofuran (THF) and 20 ml of triethylamine was cooled to 0° C. A solution of 29 g (0.15 mol) of p-toluenesulfonyl chloride in THF was added dropwise over 30 minutes. After 3 hours the precipitate of triethylamine HCl was filtered off and the filtrate evaporated at 35° C under reduced pressure. The oily residue was taken up in 500 ml of ether and washed with cold 1N HCl, aqueous NaHCO 3 and brine. It was dried over anhydrous MgSO 4 and evaporated to give the enol sulfonate IIIa (Ar = p-CH 3 C 6 H 4 ) as an oil. This was not purified but was taken up in 500 ml absolute ethanol and cooled to 0° C. To this was added 5.7 g (0.15 mol) of solid sodium borohydride. After stirring overnight the reduction was quenched with 1 molar oxalic acid solution and concentrated to about one-third the volume. This was extracted with 500 ml of ether, washed with brine, dried over MgSO 4 , and evaporated to give a tan oil. This was quickly taken up in 300 ml dry THF containing 13.5 g (0.15 mol) of oxalic acid and 20.1 g (0.15 mol) of sodium oxalate. After stirring at room temperature for one day, the solution was filtered and evaporated to dryness. This gave 35.5 g of a brown oil that was chromatographed on 600 g silicic acid and eluted with 19:1 v:v carbon tetrachloride:acetone. Like fractions were combined and evaporated to give 21 g of the cyano-ketone IVa as an oil.
Analysis, calc'd. for C 17 H 19 NO: C, 80.59; H, 7.56; N, 5.53 Found: C, 81.11; H, 7.67; N, 5.69
EXAMPLE 7
2- 2-(3-Carbomethoxypropyl)benzyl!-2-cyclohexene-1-one, IVb
A solution of 2.2 g (0.009 mol) of 2- 2-(3-cyanopropyl) benzyl!-2-cyclohexene-1-one IVa in 50 ml glacial acetic acid and 50 ml concentrated HCl was refluxed 5 hours. Evaporation of the solution gave the free acid IVc as a dark oil. This was not purified but was converted to the methyl ester by heating 2 hours in 100 ml of absolute methanol containing 10 ml of boron trifluoride-methanol complex. Evaporation gave a dark oil residue that was taken up in 200 ml of ether and washed with H 2 O, aqueous NaHCO 3 solution and brine. It was dried and evaporated. This crude ester was chromatographed on silica gel and eluted with 19:1 v:v carbon tetrachloride:acetone. Like fractions were combined to give 1.9 g of a clear colorless oil of the keto ester IVb.
Analysis, Calc'd. for C 18 H 22 O 3 : C, 75.49; H, 775 Found: C, 75.58; H, 7.62
EXAMPLE 8
2-Chloro-2- 2-(3-cyanopropyl)benzyl!-1,3-cyclohexanedione, VIIa
A suspension of 15.15 g (0.056 mol) of 2- 2-(3 -cyanopropyl)benzyl!-1,3-cyclohexanedione, IIa, finely ground, in 400 ml choloroform, was cooled to -20° C with stirring. Over the next 2 hours, a solution of 6.1 g (0.056 mol) of freshly prepared t-butyl hypochlorite was dripped in. After 3 more hours at 0° C, the solvent was removed at 35° C under reduced pressure. The residue was recrystallized from CCl 4 to give 15 g of the chloro derivative VIIIa, mp 78° C.
Analysis, Calc'd. for C 17 H 18 ClNO 2 : C, 67.21; H, 5.97; N, 4.61 Found: C, 67.59; H, 6.24; N, 4.29
EXAMPLE 9
2- 2-(3-Cyanopropyl)benzyl!-2-cyclopentene-1-one, IXa
A mixture of 8.5 g (0.028 mol) of 2-chloro-2- 2-(3-cyanopropyl)benzyl!-1,3-cycloheanedione VIIIa, and 15 g (0.14 mol) of sodium carbonate in 200 ml of xylene was refluxed with stirring for 2 hours under argon. It was then cooled, filtered and evaporated to give a brown-yellow oil. This was evaporatively distilled at 170° C/0.01 mm to give 4 g of the cyano ketone IXa as a pale yellow oil.
Analysis, Calc'd. for C 16 H 17 NO: C, 79.05; H, 7.04; N, 5.86 Found: C, 79.46; H, 7.43; N, 5.47
EXAMPLE 10
2-Chloro-2- 2-(3-Carbomethoxypropyl)benzyl!-1,3-cyclohexane dione, VIIIb
A solution of 10.5 g (0.034 mol) of 2- 2-(3-carbomethoxypropyl)benzyl!-1,3-cyclohexanedione, IIb, in 100 ml CHCl 3 was prepared and cooled to 0° C. To this was added a solution of 4.1 g (0.034 mol) of t-butyl hypochlorite in 50 ml CHCl 3 and the reaction was stirred overnight at 0° C. Evaporation of the solvent left a crystalline residue. A small sample was recrystallized from CCl 4 to give the crystalline chloro diketone VIIIb, mp 79° C.
Analysis, Calc'd. for C 18 H 21 ClO 4 : C, 64.18; H, 6.29 Found: C, 62.85; H, 6.19
EXAMPLE 11
2- 2-(3-Carbomethoxythoxypropyl)benzyl!-2-cyclopentene-1-one, IXb
A mixture of 10 g (0.026 mol) of 2-chloro-2- 2- (3-carbomethoxypropyl)benzyl!-1,3-cyclohexanedione, VIIIb nd 18.5 g (0.175 mol) of anhydrous Na 2 CO 3 was refluxed in 200 ml xylene for 2 hours. Filtration and evaporation gave a brown oil (10 g). Evaporative distillation at 175° C/0.2 mm gave 6 g of a pale yellow oil. This was chromatographed on silica gel and eluted with 7:3 v:v CCl 4 :acetone. Like fractions were combined to give 4.1 g of the keto ester IXb as a pale yellow oil.
Analysis, Calc'd. for C 17 H 20 O 3 : C, 74.97; H, 7.40 Found: C, 74.10; H, 7.38
EXAMPLE 12
4- 2-(3-Chloropropyl)phenyl!-2-butanone, 7
A mixture of 258 g (1.27 mol) of 2-(3-chloropropyl)benzyl chloride, 2, 140 g (1.4 mol) of 2,4-pantanedione, 6, 175 g (1.27 mol) potassium carbonate, and 700 ml of absolute ethanol was stirred at reflux for 18 hours. Evaporation of the alchohol gave a residue which was partitioned between ether and water. The organic phase was dried over anhydrus MgSO 4 , concentrated and the residue distilled to give the chloro ketone 7, 218 g, bp 123°-127° C/0.2 mm.
Analysis, Calc'd. for C 13 H 17 ClO: C, 69.47; H, 7.85 Found: C, 70.39; H, 7.85
EXAMPLE 13
4- 2-(3-Cyanopropyl)phenyl!-2-butanone, 8.
A solution of 218 g (0.97 mol) of 4- 2-(3-chloropropyl)phenyl!-2-butanone, 7, in 700 ml dimethyl sulfoxide containing 200 g dry sodium cyanide was heated to 100° C for 3 hours. The dimethyl sulfoxide was distilled out under high vacuum and the residue partitioned between ether and H 2 O. The ether phase was separated, dried over anhydrous MgSO 4 , concentrated and the residue distilled to give 164 g of the keto-nitrile 8, bp 143 -146° C/0.3 mm.
Analysis, Calc'd. for C 14 H 17 NO: C, 78.10; H, 7.96; N, 6.51 Found: C, 77.83; H, 8.08; N, 6.40
EXAMPLE 14
4- 2-(3-Carboxyproply)phenyl!-2-butanone, 9
A solution of 50 g (0.23 mol) of 4- 2-(3-cyanoproply)phenyl!-2-butanone, 8 in 125 ml glacial acetic acid and 125 ml concentrated HCl was refluxed overnight. The solution was evaporated and the residue diluted with H 2 O. The precipitate was recrystallized from benzene-petroleum ether to give 42.5 g of the keto acid 9, mp 59°-61° C.
Analysis, Calc'd. for C 14 H 18 0 3 : C, 71.77; H, 7.74 Found: C, 72.60; H, 7.99
EXAMPLE 15
4- 2-(3-Carbomethoxypropyl)phenyl!-2-butanone, 10
A solution of 117 g (0.5 mol) of 4- 2-(3-carboxypropyl) phenyl!-2-butanone, 9, in 200 ml of absolute methanol containing 2 equivalents (1.0 mol) of boron trifluoride methanol complex was reluxed for 16 hours. It was concentrated and the residue washed with H 2 O, then aqueous sodium bicarbonate solution. After drying, it was distilled to give 111 g of the keto ester 10, bp 132°-136° C/0.2 mm.
Analysis, Calc'd. for C 15 H 20 0 3 : C, 72.55; H, 8.12 Found: C, 71.71; H, 8.10
EXAMPLE 16
2- 2-(3-Carboxyproply)benzyl!-1,3,4-cyclopentanetrione, 11
A solution of 96 g (0.44 mol) of 4- 2-(3-carbomethoxy proply)phenyl!-2-butanone, 10, and 129 g (0.88 mol) of diethyl oxalate was added dropwise at room temperature to a solution made by dissolving 20.2 g (0.88 g-atm) sodium in 200 ml absolute ethanol. After the addition was complete, the reaction was stirred 1 hour at room temperature and 1 hour at 50° C. It was then concentrated, the residue taken up in H 2 O, and acidified with 70 ml concentrated HCl. The precipitated material was extracted into ether and washed twice with H 2 O. The acidic material was then extracted out of this ether phase with aqueous sodium carbonate solution. Upon acidification of the sodium carbonate solution a red oil separated. This oil was heated overnight in a solution of 200 ml concentraed HCl and 200 ml methanol. The reaction mixture was diluted with 300 ml H 2 O and extracted with ether. Evaporation of the ether gave 70 g of red oil. This was chromatographed on 400 g silicic acid and eluted with benzene:ethanol. Like fractions were combined and crystallized. Recrystallization from benzene gave 23 g of the trione acid 11, mp 123° C.
Analysis, Calc'd. for C 16 H 16 O 5 : C, 66.66; H, 5.60 Found: C, 66.30; H, 5.58
EXAMPLE 17
2- 2-(3-Carbomethoxypropyl)benzyl!-1,3,4-cyclopentanetrione, XIIa
A solution of 45 g (0.16 mol) of 2- 2-(3-carboxy propyl)benzyl!-1,3,4-cyclopentanetrione, 11, in 100 ml absolute MeOH containing 10 ml concentrated HCl was stirred 24 hours at room temperature. Evaporation gave a dark residue that was taken up in ether and extracted with aqueous NaHCO 3 . Neutralization gave 40 g of crude ester. Chromatography on 1000 g silicic acid and elution with 4:1 v:v benzene:ethyl acetate gave 32 g of the trione ester XIIa as a red oil.
Analysis, Calc'd for C 17 H 18 O 5 : C, 67.54; H, 6.00; N.E. (neutralization equivalent), 302.3 Found: C, 68.71; H, 6.16; N.E., 306.3
EXAMPLE 18
2- 2-(3-Carbomethoxypropyl)benzyl!-4-hydroxy-1,3-cyclopentane dione, XIIIa
A toluene solution of 30.5 g (0.1 mol) of 2- 2-(3-carbomethoxypropyl)benzyl!-1,3,4-cyclopentanetrione, XIIa, was thoroughly dried by azeotropic distillation. Removal of the toluene gave a red oil that was taken up in 200 ml of 2-propanol. Five grams of Pd/C was added and the compound hydrogenated at 0.25 psi for 3 days. The catalyst was filtered and the solvent evaporated to give the crude product. This was chromatographed on silicic acid and eluted with 4:1 benzene:ethyl acetate. The major fraction amounted to 20 g of the hydroxy dione XIIIa as a clear, light tan oil.
Analysis, Calc'd. for C 17 H 20 O 5 : C, 67.09; H, 6.62; N.E., 304.3 Found: C, 67.03; H, 6.85; N.E., 322.0
EXAMPLE 19
2- 2-(3-Carbomethoxypropyl)benzyl!-4-hydroxy-2-cyclopentene-1-one, XVa
A solution of 19 g (0.063 mole) of the hydroxydione XIIIa in 200 ml dry ether was cooled to 0° C. To this was added 10 ml triethylamine followed by a solution of 14 g (0.063 mol) of 2-mesitylenesulfonyl chloride in 50 ml of ether. After stirring 30 minutes at 0° C the solution was allowed to warm to room temperature. It was then washed with cold H 2 O, 1N HCl, brine, then dried over anhydrous CaCl 2 and concentrated at 32° C under reduced pressure. The light colored oily residue of the enol sulfonate XIVa (Ar = 2,4,6-C 6 H 2 --) was not purified but was used directly in the next step. It was taken up in 300 ml absolute ethanol and cooled to 0° C. 2.4 g (0.063 mol) of sodium boronhydride was added and the reaction stirred overnight. The reaction was then quenched with 1 molar oxalic acid, the solution concentrated to a third of its volume, and the residue partitioned between ether and H 2 O. The ether phase was separated, dried over anhydrous MgSO 4 , and evaporated under reduced pressure to give a brown residue. This was taken up in 100 ml dry THF and stirred with 5.7 g (0.063 mol) of oxalic acid and 8.5 g (0.063 mol) of sodium oxalate for 16 hours. Filtration and evaporation gave a residue that was twice chromatographed; first on silicic acid and second on silica gel, both times eluting with 9:1 v:v benzene:ethyl acetate. This gave 5 g of the hydroxy ketone XVa as a pale yellow oil; n D 19 = 1.5499.
Analysis, Calc'd. for C 17 H 20 O 4 : C, 70.81; H, 6.99 Found: C, 70.74; H, 7.23
EXAMPLE 20
2- 2-(3-Carboethoxypropyl)benzyl!-4-hydroxy-2-cyclopentene-1-one, XVb
Twenty grams (0.062 mol) of 2- 2-(3-carboethoxypropyl)benzyl!-1,3,4-cyclopentanetrione, XIIb, was prepared in the same manner as the methyl ester XIIa. This was isolated but not purified. Hydrogenation of this with Pd/C gave 14 g of 2- 2-(3-carboethoxypropyl)benzyl!-4-hydroxy-1,3-cyclopentanedione XIIIb; the reduction was performed in the same was as for the methyl ester XIIIa, previously cited. This hydroxy dione ester was converted to the desired hydroxy ene one XVb in the same way as the methyl ester XVa already cited. This gave 7 g of a clear colorless oil.
Analysis, Calc'd. for C 18 H 22 O 4 : C, 71.50; H, 7.34 Found: C, 71.88; H, 7.30
The following examples illustrate preparation of certain halovinyl alcohols useful in preparation of the cuprates V employed in preparation of compounds of structure I.
EXAMPLE 21
(E)-1-Iodo-3-(S)-hydroxy-2-phenyl-1-butene, XXXIIa
Phenylacetone (Aldrich Chem. Co. 13,538--0; Beilstein 7, 303), XXVIa (101 g, 0.75 mol) was combined with 100 g (1.35 mol) of ethyl formate and added all at once to a suspension of 50 g (0.75 mol) of sodium ethoxide in 500 ml of THF. After 3 hours at room temperature the brown solution was diluted with 400 ml of H 2 O. Following extraction with benzene to remove unreacted starting material, the aqueous phase was acidified with dilute HCl. The product was extracted with benzene, washed with H 2 O, dried over MgSO 4 , and concentrated to give an oil. Distillation gave 39 g (0.24 mol) of (Z)-1-hydroxymethylene-1-phenylacetone, XXVIIa, as a colorless oil, bp 65°-69° C (0.3 mm).
A solution of 39 g (0.24 mol) of this compound and 24 g of pyridine in 100 ml of methylene chloride was treated dropwise at 0° C with a solution of 48 g (0.25 mol) of p-toluenesulfonyl chloride and 12 g of pyridine in 75 ml of methylene chloride. After 3 hours at 0° C, the reaction was worked up to give a dark crystalline residue of (Z)-1-tosyloxymethylene-1-phenylacetone XXVIIIa. A sample was recrystallized from benzene to give white crystals, mp 81-85 (dec).
Analysis, Calc'd for C 17 H 16 SO 4 : C, 64.54; H, 5.10 Found: C, 64.95; H, 5.11
The main portion of this tosylate was combined with a solution of 120 g (0.8 mol) of sodium iodide in 600 ml of acetone containing 3 ml of concentrated sulfuric acid. After stirring overnight at room temperature, the mixture was poured into 700 ml of H 2 O and the product extracted out with methylene chloride. The aqueous layer was washed with benzene and the combined organic layers dried and evaporated to give a crystalline residue of (E)-1-iodomethylene-1-phenylacetone, XXIXa. A sample of this was recrystallized from petroleum ether to give white crystals, mp 97° C.
Analysis, Calc'd. for C 10 H 9 IO: C, 44.14; H, 3.33 Found: C, 44.50; H, 3.40
The main portion of this iodovinyl ketone was reduced with sodium borohydride in absolute ethanol. Work-up gave 40 g of a light yellow oil of the desired dl-(E)-1-iodo-3-hydroxy-2-phenyl-1-butene XXXa. This racemic alcohol was not purified at this point but was resolved by the following procedure.
The crude alcohol, 20 g, was heated at 80°C for 1 hour with 22 g (0.15 mol) of phthalic anhydride in 50 ml of triethylamine. The reaction was then concentrated in vacuo and the yellow oily residue partitioned between chloroform and dilute hydrochloric acid. The organic phase was washed twice with H 2 O, dried over MgSO 4 , and evaporated to give a light orange oil of the hydrogen phthalate ester XXXIa. This was dissolved in ethyl acetate and treated with 18.5 g of L-(-)-α-methylbenzylamine and the resulting solution cooled overnight. The salt precipitated and after three recrystallizations from ethanol there was obtained 17 g of the α-methylbenzylammonium salt, α D =+26.8° (C 2.3, CH 3 --OH).
Analysis, Calc'd. for C 26 H 26 INO 4 : C, 57.47; H, 4.82; N, 2.58 Found: C, 57.37; H, 4.85; N, 2.49
The above salt (16 g, 0.03 mol) was refluxed with 200 ml of 20% sodium hydroxide for 3 hours. When cool the mixture was diluted with water and extracted three times with ether. The combined ether extracts were washed with dilute HCl, then saturated NaHCO 3 and dried over MgSO 4 . The ether was evaporated and the resulting oil was dried overnight under 0.05 mm vacuum. This gave 7 g of the resolved alcohol XXIIa as a colorless oil, α D = -14.33° (c 2.3, CH 3 OH).
Analysis, Calc'd. for C 10 H 11 IO: C, 43.82; H, 4.05 Found: C, 43.90; H, 4.19
EXAMPLE 22
(E)-2-iodomethylene-(S)-cyclohexanol, XXIIb
As in the previous example, 200 g (2.0 mol) of cyclohexanone was reacted with ethyl formate to give 140 g of 2-hydroxymethylenecyclohexanone, XXVIIb, bp 71-74° C (0.6 mm). Forty grams (0.32 mol) of this substance was dissolved in 150 ml CH 2 CL 2 . containing 30 g of pyridine and treated at -5° C with a solution of 64 g (0.34 mol) of p-toluenesulfonyl chloride and 16 g of pyridine in 150 ml CH 2 Cl 2 . The reaction was stirred overnight at this temperature. Work-up in the usual manner gave the enol tosylate XXVIIIb. This was not isolated but added directly to a solution of 150 g (1.0 mol) NaI in dry acetone. After stirring overnight at room temperature this was worked up in the usual manner to give (E)-2-iodomethylenecyclohexanone, XXIXb, as a red oil. Again this was not isolated but was reduced with NaBH 4 in EtOH to give crystalline dl-(E)-2-iodomethylenecyclohexanol, XXXb. Recrystallization from petroleum ether gave 40 g of white needles, mp 80° C.
Analysis, Calc'd. for C 7 H 11 IO: C, 35.31; H, 4.66 Found: C, 35.56; H, 4.88
Material from several runs was combined to give 60 g of the alcohol. This was converted to the hemiphthalate salt XXXIb as before to give 70 g of white crystals, mp 73° C. When treated with 24 g of L-(-)-α-methylbenzylamine this gave a salt. Two recrystallizations from methanol-ethyl acetate gave 30 g of the salt, mp 171°-172° C, α D =+30.4° (c 2.0, CH 3 OH).
Analysis, Calc'd. for C 23 H 26 INO 4 : C, 54.44; H, 5.17; N, 2.76 Found: C, 54.09; H, 5.18; N, 3.11
Hydrolysis of this salt with 20% NaOH as in the previous example gave, after recrystallization from ligroine, 11 g of the alcohol XXIIb, mp 81° C, α D =-25.1° (c 2.0, CH 3 OH).
Analysis, Calc'd. for C 7 H 11 IO: C, 35.31; H, 4.66 Found: C, 35.19; H, 4.65
EXAMPLE 23
(E)-2-Bromomethylene-(S)-cyclooctanol, XXIIc
As in previous examples, 126 g of cyclooctanone, XXVIc, was reacted with ethyl formate to give 95 g (0.62 mol) of 2-hydroxymethylene-cyclooctanone, XXVIIc, bp 87°-92° C (0.4 mm).
This enol was dissolved in 300 ml of CH 2 Cl 2 containing 61 g of pyridine and treated dropwise at 0° C with a solution of 120 g (0.63 mol) of p-toluenesulfonyl chloride in 100 ml of CH 2 Cl 2 containing 30 g of pyridine. After stirring overnight at 0° C, the reaction was worked up as before to yield the enol tosylate XXVIIIc. This was not isolated but was combined directly with a solution of 150 g (1.73 mol) of lithium bromide in 400 ml of acetone containing 3 ml of concentrated H 2 SO 4 . After 1 hour of heating the reaction was worked up in the usual manner to give (E)-2-bromomethylenecyclooctanone, XXIXc, as a yellow-orange oil. A small sample was purified by evaporative sublimation at 85° C (0.5 mm).
Analysis, Calc'd. for C 9 H 13 BrO: C, 49.79; H, 6.03 Found: C, 48.49; H, 6.24
The bulk of this ketone was reduced directly with NaBH 4 in EtOH. This gave the desired dl-(E)-2-bromomethylenecylcooctanol, XXXc, as a light yellow oil, 95 g, bp 84° C (0.2 mm).
Analysis, Calc'd. for C 9 H 15 BrO: C, 49.33; H, 6.90 Found: C, 49.99; H, 7.25
This alcohol was resolved, as in the previous examples, by conversion to the half ester XXXIc and then to the salt with L-(-)-α-methylbenzylamine. Three recrystallizations of this salt from 2-propanol gave 37 g, mp 144°-145° C, α D = +36.0 (c 2.0, CH 3 OH).
Analysis, Calc'd. for C 24 H 30 BrNO 4 : C, 61.47; H, 6.19; N, 2.87 Found: C, 61.30; H, 6.28; N, 2.80
This was hydrolyzed with 20% NaOH as before to give after recrystallization from ligroine, the alcohol XXIIc, mp 54° C. α D = +7.0 (c 2.0, CH 3 OH).
Analysis, Calc'd. for C 9 H 15 BrO: C, 49.33; H, 6.90 Found: C, 50.27; H, 7.29
EXAMPLE 24
3-(S)-Hydroxy-1-iodo-1-(E) Octene XXIId
This compound was prepared and resolved as described in Kluge, et al., J. Amer. Chem. Soc. 94:7827 (1972).
The following Examples are illustrative of the preparation of compounds of structures I of the invention. Unless otherwise indicated in the recitation of physical properties of the exemplary compounds, the optical rotation analysis was performed in methanol, c 1.0 to 2.0 and thin layer chromatographic analysis was performed in the manner of Srivastava, et al., Lipids 8:592 (1973) on Merck 20 × 20 cm silica gel 60 plates.
EXAMPLES 25-26
Methyl 4-2'-{ 2S-(3S-hydroxy-1E-octenyl)-3R-hydroxy-5-oxocyclo-pent-1R-yl!methyl}phenylbutanoate
(5,6-Dinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4250)
Methyl 4-2'-{ 2S-(3S-hydroxy-1E-octenyl)-3S-hydroxy-5-oxocyclo-pent-1R-yl!methyl}phenylbutanoate
(Ent-15-epi-5,6-dinor-4,7-inter-o-phenylene prostaglandin E 1 methyl ester; Tr. No. 4251)
Eleven ml of 2.1 molar t-butyl lithium solution in pentane was placed in a 50 ml round bottom flask equipped with magnetic stirrer, argon inlet and outlet, dropping funnel and thermometer. It was cooled to -78° C and stirred. To this was added, dropwise over a 20 minute period, 3.26 g (0.01 mole) of (E)-3(S)-(1-ethoxyethoxy-1-iodo-1(E)octene (XXIIId, wherein T 2 , = n-C 5 H 11 , T 1 =H). An exothermic reaction occurred accompanied by the formation of a white precipitate. After an additional 20 minutes at -78° C, this mixture was added to a second solution, also at -78° C, made by dissolving 1.3 g (0.01 mol) of cuprous n-propyl acetylide and 3.26 g (0.02 mol) of hexamethylphosphorous triamide (reference insert 2b) in 10 ml of ether. This gave a dark red-brown mixture. To this was added 1.24 g (0.0034 mol) of 2- 2-(3-carbomethoxypropyl)benzyl!-4-(1-ethoxyethoxy)-2-cyclopentene-1-one(XVIa wherein T = COOCH 3 ) in 5 ml of ether. The color of the reaction lightened somewhat and it was stirred at -30° C for 2 hours. At the end of this time the reaction was quenched by pouring it into 200 ml of 1 molar ammonium sulfate solution and stirring for 20 minutes. After filtration through a diatomaceous earth filter aid the ether phase was separated and washed with H 2 O, saturated NaHCO 3 , and brine. The ether was removed under reduced pressure, the oily residue taken up in 200 ml of 65% aqueous acetic acid, then stirred at 35° C for 2 hours. Evaporation of solvent gave a light brown oil that was taken up in 100 ml of ether and washed successively with H 2 O, saturated NaHCO 3 solution and brine. After drying over anhydrous CaCl 2 , the ether was removed to give a light colored oil of the two isomers of XVIIa.
This mixture was chromatographed on 50 g silica gel and eluted with 4:1 v:v benzene:ethyl acetate. About 200 ml of void volume was discarded, then 15 ml fractions were collected.
Fractions 190-310 were combined and evaporated to give 440 mg of a light tan oil of the compound of structure XVIIa(Id, wherein: T = COOCH 3 ; T 1 = H; and T 2 = n-C 5 H 11 ) as the ent isomer (Tr. No. 4251: α! D + 54.8, rf = 0.48) having the following physical characteristics:
NMR (CDCl 3 ): δ 3.6 (3H,s); 5.4 (2H,m); 7.1 (4H,s) Mass. Spectrum (70 eV)/m/e: 416 (M + )
Fractions 341-470 were combined and evaporated to give 400 mg of the compound of structure XVIIa as the nat isomer (Tr. No. 4250: α! D = 67.3; rf = 0.45).
EXAMPLE 26A
4-2'-{ 2S-(3S-Hydroxy-1E-Octenyl)-3R-hydroxy-5-oxocyclopent-1R-yl!methyl} phenylbutanoic acid
(5,6-Dinor-4,7-inter-o-phenyleneprostaglandin E; Tr. No. 4730)
A phosphate buffer of approximate pH 7.4 was prepared by dissolving 4.7 g of sodium dihydrogen phosphate monohydrate and 25 g of disodium hydrogen phosphate in 1 liter of deionized water at 37° C. To this well-stirred solution was added 10 mg of the enzyme hog liver carboxylic ester hydrolase (EC 3.1.1.1, from Sigma Chemical Company) followed by 250 mg of methyl 4-2'-{ 2S-3S-hyroxy-1E-octenyl)-3R-hydroxy-5-oxocyclo-pent-1R-yl!methyl}phenylbutanoate (Tr. No. 4250 of Example 25) dissolved in 10 ml of absolute methanol. A milky solution resulted which gradually became clear over the next 20 minutes. After one hour, the temperature was lowered to 5° C and the pH of the solution adjusted to 2 with dilute HCl. The reaction mixture was extracted with two 250 ml portions of ethyl acetate. These were combined, dried over anhydrous MgSO 4 , filtered and evaporated. The crude product so obtained was chromatographed on 50 g silica gel and eluted with 9:1 v:v benzene:methanol. Ten ml fractions were collected and fractions 8 to 25 were combined to yield 170 mg of the desired acid as a pale yellow oil of structure XVIIc (Tr. No. 4730: α! D =-54.5°; rf=0.32) having the following physical characteristics:
NMR (CDCl 3 ): δ 7.1 (4H,s); 5.9 (2H,m); 0.9 (3H,m). Mass Spectrum (70 eV) m/e: 366 (M + -2H 2 0).
EXAMPLES 27- 28
Methyl 4-2'-{2S-(3S-Hydroxy-1E-octenyl)-6-oxocyclohex-1S-yl!methyl}phenylbutanoat
(11-Deoxy-ent-15-epi-9a-homo-5,6-dinor-4,7-inter-o-phenylene-prostaglandin E 1 methyl ester; Tr. No. 4211)
Methyl 4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-6-oxocyclohex-1R-yl!methyl}phenylbutanoate
(11-Deoxy-9a-homo-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4212)
Upon selection of suitable reactants, the general procedure of Examples 25- 26 yielded the title compounds of structure VIb (Ib, wherein: T = COOCH 3 ; T 1 = H; and T 2 = n-C 5 H 11 ) either as the ent isomer (Tr. No. 4211: α! D = +14.66; rf = 0.70) or the nat isomer (Tr. No. 4212: α! D = -8.98; rf = 0.67) having the following physical characteristics:
NMR (CDCl 3 ): δ 3.6(3H,s); 5.5(2H,m); 7.1(4H,s) Mass Spectrum (70 eV) m/e: 414 (M + )
EXAMPLES 29- 30
4-2'-{ 2S-(2S-hydroxy-1E-octenyl)-6-oxocyclohex-1S-yl!methyl}-phenylbutanenitrile
(11-Deoxy-ent-15-epi-9a-homo-2-decarboxy-2-cyano-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ; Tr. No. 4213)
4-2'-{ 2R-(2S-hydroxy-1E-octenyl)-6-oxocyclohex-1R-yl!methyl}phenylbutanenitrile
(11-Deoxy-9a-homo-2-decarboxy-2-cyano-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ; Tr. No. 4214)
Upon selection of suitable reactants, the general procedure of Examples 25- 26 yielded the title compounds of structure VIa (Ib, wherein: T = CN; T 1 32 H; and T 2 = n-C 5 H 11 ) either as the ent isomer (Tr. No. 4213: α! D = + 16.2; rf = 0.70) or the nat isomer (Tr. No. 4214: α! D = -2.1; rf = 0.65) having the following physical characteristics:
NMR (CDCl 3 ): δ 0.9 (3H,m); 5.5 (2H,m); 7.1 (4H,s) Mass Spectrum (70 eV) m/e: 381 (M + )
EXAMPLES 31-32
methyl 4-2'-{ (2S-(2S-hydroxy-E-cyclohexylidenemethyl)-6-oxocyclohex-1S-yl!methyl}-phenylbutanoate
(11-Deoxy-ent-15-epi-9a-homo-14,19-cyclo-5,6,20-trinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4230)
methyl 4-2'-{ 2R-(2S-hydroxy-E-cyclohexylidenemethyl)-6-oxocyclohex-1R-yl!methyl}phenylbutanoate
(11-Deoxy-9a-homo-14,19-cyclo-5,6,20-trinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4231)
Upon selection of suitable reactants, the general procedure of Examples 25-26 yielded the title compounds of structure VIb (IB, wherein: T = COOCH 3 ; T 1 and T 2 = --(CH 2 ) 4 --) either as the ent isomer (Tr. No. 4320: α! D = +42.0; rf = 0.64) or the nat isomer (Tr. No. 4231: α! D = - 36.4; rf = 0.62) having the following physical characteristics:
NMR (CDCl 3 ): δ 3.7 (3H,s); 5.3 (1H,m): 7.2 (4H,s) Mass Spectrum (70 eV) m/e: 384 (M 30 )
EXAMPLES 33-34
methyl 4-2'-{ 2S-(3S-hydroxy-1E-octenyl)-5-oxocyclopent-1S-yl!methyl}-phenylbutanoate
(11-Deoxy-ent-15-epi-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4267)
methyl 4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-5-oxocyclopent-1R-yl!methyl}phenylbutanoate
(11-Deoxy-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4266)
Upon selection of suitable reactants, the general procedure of Examples 25-26 yielded the title compounds of structure Xb (Ic, wherein: T = COOCH 3 ; T 1 = H; and T 2 = n-C 5 H 11 ) either as the ent isomer (Tr No. 4267: α! D = +29.4; rf = 0.68) or the nat isomer (Tr. No. 4266: α! D = -40.5; rf = 0.63) having the following physical characteristics:
NMR (CDCl 3 ): δ 0.9 (3H,t,J=4Hz); 3.6 (3H,s); 5.4 (2H,m); 7.2 (4H,s) Mass Spectrum (70 eV) m/e: 400 (M + )
EXAMPLE 35
methyl 4-2'-{ 2S-(3R-hydroxy-2-phenyl-1E-butenyl)-5-oxocyclopent-1S-yl!methyl}-phenylbutanoate
(11-deoxy-epi-5,6-dinor-4,7-inter-14-phenyl-o-phenylenetetranorprostaglandin E 1 methyl ester; Tr. No. 4298)
Upon selection of suitable reactants, the general procedure of Examples 25-26 yielded the title compound of structure Xb (Ic, wherein: T = COOCH 3 ; T 1 = C 6 H 5 ; and T 2 = CH 3 ) as a mixture of isomers (Tr No. 4298: α! D = + 11.2; rf = 0.64) which could not be separated, having the following physical characteristics:
NMR (CDCL 3 ): δ 3.1(2H,q,J=2Hz); 3.3 (3H,s); 6.5 (1H,m); 6.7 (4H,s) Mass Spectrum (70 eV) m/e: 420 (M + )
EXAMPLES 36-37
4-2'-{ 2S-(3S-hydroxy-1E-octenyl)-5oxocyclopent-1S-yl!methyl}-phenylbutanenitrile
(11-Deoxy-ent-15-epi-2-decarboxy-2-cyano-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ; Tr. No. 4303)
4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-5-oxocyclopent-1R-yl!methyl}phenylbutanenitrile
(11-Deoxy-2-decarboxy-2-cyano-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ; Tr. No. 4302)
Upon selection of suitable reactants, the general procedure of Examples 25-26 yielded the title compounds of structure Xa (Ic, wherein: T = CN; T 1 = H; and T 2 = n-C 5 H 11 ) either as the ent isomer (Tr. No. 4303: α! D = +45.5; rf = 0.65) or the nat isomer (Tr. No. 4302: α! D = - 46.3; rf = 0.59) having the following physical characteristics:
NMR (CDCl 3 ): δ 1.1 (3H,t,J=4Hz); 5.5 (2H,m); 7.3 (4H,s) Mass Spectrum (70 eV) m/e: 367 (M + )
EXAMPLES 38-39
methyl 4-2'-{ 2S-(2S-hydroxy-E-cyclohexylidenemethyl)-5-oxocyclopent-1S-yl!methyl}-phenylbutanoate
(11-Deoxy-ent-15-epi-14,19-cyclo-5,6,20-trinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4305)
methyl 4-2'-{ 2R-(2S-hydroxy-E-cyclohexylidenemethyl)-5-oxocyclopent-1R-yl!methyl}phenylbutanoate
(11-Deoxy-14,19-cyclo-5,6,20-trinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4304)
Upon selection of suitable reactants, the general procedure of Examples 25-26 yielded the title compounds of structure Xb (Ic, wherein: T = COOCH 3 ; T 1 and T 2 = --(CH 2 ) 4 --) either as the ent isomer (Tr. No. 4305: α! D = +71.0; rf = 0.62) or the nat isomer (Tr. No. 4304: α! D = - 61.7; rf = 0.58) having the following physical characteristics:
NMR (CDCl 3 ): δ 3.6 (3H,S); 5.1 (1H,d): 7.0 (4H,s) Mass spectrum (70 eV) m/e: 384 (M 30 )
EXAMPLE 40
4-2'-{ 2S-(2R-hydroxy-E-cyclooctylidinemethyl)-3S-hydroxy-5-oxocyclopent-1S-yl!methyl}phenylbutanoate
(ent-14,20-methylene-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ethyl ester; Tr. No. 4513)
Upon selection of suitable reactants, the general procedures of samples 25-26 yielded the title compound of the structure XVIIb (Id, wherein: T = COOC 2 H 5 ; T 1 and T 2 = --(CH 2 ) 6 --) as the ent (but not 15-epi) isomer (Tr. No. 4513: α! D = +109.8; rf = 0.58) having the following physical characteristics:
Nmr (cdcl 3 ) : δ 1.2(3H,t,J=7Hz); 4.1(2H,d,J=7Hz); 5.1 (1H,d,J=9Hz); 7.2(4H,s)
Mass Spectrum (70 eV) m/e: 384 (M + )
EXAMPLES 41-44
ethyl 4-2'-{ 2R-(3S-hydroxyl-1E-octenyl)-5-oxo-3-cyclopenten-1R-yl!methyl}pehenylbutanoate
(5,6-dinor-4,7-inter-o-phenyleneprostaglandin A 1 ethyl ester; Tr. No. 4310) ethyl 4-2'{ 2S-(3-hydroxyl-1E-octenyl)-5-oxo-3-cyclopenten-1S-yl!methyl)phenylbutanoate
(ent-15-epi-5,6-dinor-4,7-inter-o-phenyleneprostaglandin A 1 ethyl ester; Tr. No. 4311)
ethyl 4-2'-{ 2S-hydroxy-1E-octenyl)-3S-hydroxy-5-oxocyclopent-1S-yl}methyl)phenylbutanoate
(ent-15-epi-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ethyl ester; Tr. No. 4318)
ethyl 4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-3R-hydroxy-5-oxocyclopent-1R-yl!methyl}phenylbutanoate
(5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ethy ester; Tr. No. 4309)
A solution of 100 ml of 0.96 molar t-butyl lithium in n-pentane was placed in a 250 ml round bottom flask fitted with an argon inlet, dropping funnel, magnetic stirring bar, thermometer, and plastic cannula. The solution was cooled to -78° C and a second solution of 13.7 g (0.042 mol) of (E)-3-(S)-(1-ethoxyethoxy)- 1-iodo-1-octene, (XXIIId) in 13 ml of dry ether was slowly added over a 30 minute period. After 30 more minutes this mixture containing the lithio derivative XXIVd, was pumped through the cannula into a second solution (also at -78° C) made by dissolving 5.5 g (0.042 mol) of cuprous n-propylacetylide in 45 ml of dry ether containing 13.7 g (0.084 mol) of hexamethylphosphorous triamide. After 20 minutes stirring at -30° C this consisted of a red solution of the lithium cuprate Vd. To it was added a solution of 5.2 g (0.014 mol of 2- 2-(3-carboethoxypropyl) benzyl!-4-(1-ethoxyethoxy)-2-cyclopenten-1-one XVIb (T 1 = H, T 2 = n-C 5 H 11 ) in 23 ml of dry ether. After stirring 2 hours at -30° C, the reaction was quenched by pouring it into 1 liter of 1 molar aqueous NH 4 Cl solution and stirring for 20 minutes. The layers were then separated and the aqueous layer extracted with two 100 ml portions of ether. The combined ether extracts were dried over anhydrous MgSO 4 and concentrated under reduced pressure to give an oil. This oil was stirred at 37° C with 400 ml of 60% aqueous acetic acid for three hours, filtered, and concentrated under reduced pressure to give an oil. The oil was taken up in ether and washed with saturated NaHCO 3 solution, H 2 O, and brine. It was dried and evaporated and the oil that resulted was chromatographed on 250 g of silica gel. Elution was with 4:1 v:v benzene:ethyl acetate and 20 ml fractions were collected.
Fractions 221-235 were combined to give 570 mg of an oil of the compound of structure XIXb (Ie, wherein: T = COOC 2 H 5 ; T 1 = H; T 2 = n-C 5 H 11 ) as the ent isomer (tr. No. 4311: α! D = -95.2; rf = 0.55 in 4:1, v:v,, benzene:ethyl acetate) having the following physical characteristics:
MNR (CCl 4 ): δ 4.1(SH,q); 5.2(2H,dd); 6.1(1H,dd); 7.1(4H,s); 7.3(1H,dd)
Mass Spectrum (70 eV) m/e: 412 (M + )
Fractions 251 to 265 were combined to give 300 ml of the compound of structure XIXb as the nat isomer (Tr. No. 4310: α! D = +90.5 rf = 0.51 in 4:1, v:v, benzene:ethyl acetate).
Fractions 361 to 665 were combined to give 300 g of an oil of the compound of structure XIIb (Id, wherein: T = COOC 2 H 5 ; T 1 = H; and T 2 = n-C 2 H 5 ) as the ent isomer (Tr. No. 4318: α! D = +57.3; rf = 0.35 in 4:1, v:v, benzene:ethyl acetate) having the following physical characteristics:
NMR (CCl 4 ): δ 4.1(2H,q); 5.4(2H,m); 7.1(4H,s)
Mass Spectrum (70 eV) m/e: 430 (M + )
Fractions 691 to 820 were combined to yield 740 mg of the compound of sturcture XIIb as the nat isomer (Tr. No. 4309: α! D = -58.7; rf = 0.28 in 4:1, v:v, benzene:ethyl acetate).
EXAMPLE 45
methyl 4-2'-{ 2R-(3S-hydroxyoctyl) -5-oxocyclopent-1R-yl!methyl)-phenylbutanoate
(11-Deoxy-13,14-dihydro-5,6-dinor-4,7-inter-o-phenylene prostaglandin E 1 methyl ester; Tr. No. 4269)
150 mg (0.0004 mol) of the nat isomer compound of Example 34 (Tr. No. 4266) was dissolved in 50 ml of absolute methanol, 50 mg of PtO 2 was added, and hydrogenation effected at 30 psig hydrogen pressure for 6 hours at room temperature. The catalyst was filtered and the solvent evaporated to give 150 mg of an oil that was chromatographed on 10 g silica gel and eluted with 9:1, v:v, benzene:ethyl acetate. 10 ml fractions were collected. Fractions 18 to 36 were combined to give 80 mg of a clear white oil of the compound of structure XIb (Ic, wherein: T = COOCH 3 ; T 1 = H; and T 2 = n-C 5 H 11 ) as the nat isomer (Tr. No. 4269: α! D = +5.01; rf = 0.38 in 4:1, v:v, CCl 4 :acetone) having the following physical characteristics:
NMR (CCl 4 ): δ 0.9(3H,t,J=4Hz); 3.6(3H,s); 7.1(4H,s)
Mass Spectrum (70 eV) m/e: 402 (M + )
EXAMPLE 46
methyl 4-2'-{ 2S-(3S-hydroxyoctyl)-5-oxocyclopent-1S-yl!methyl}-phenylbutanoate
(11-Deoxy-13,14-dihydro-ent-15-epi-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 methyl ester; Tr. No. 4297)
The title compound is secured in the manner of Example 45 when the ent isomer of Example 33 (Tr. No. 4267) is employed as the starting compound. Thus hydrogenation of 150 mg of the selected starting compound yielded 57 mg of its dihydro analogue of the structure XIb (Ic, wherein: T = COOCH 3 ; T 1 = H; and T 2 = n-C 5 H 11 ) as the ent isomer (Tr. No. 4297: α! D = -17.43; rf = 0.34 in 4:1 CCl 4 :acetone) having the following physical characteristics:
NMR (CCl 4 ): δ 0.9(3H,t,J=4Hz); 3.6(3H,s); 7.1(4H,s)
Mass Spectrum (70 eV) m/e: 402 (M + )
EXAMPLE 47
4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-5-oxocyclopent-1R-yl}methyl)-phenylbutanoic acid
(11-Deoxy-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ; Tr. No. 4399)
A solution of 600 mg (0.0015 mol) of the nat isomer compound of Example 34 (Tr. No. 4266) in 2.5 ml of MeOH was combined with 4.5 ml of 5% KOH in 3:1, v:v, MeOH:H 2 O. After stirring for 3 hours the reaction solution was concentrated to dryness at 32° C under reduced pressure. The residue was partitioned between 25 ml of ether and 25 ml H 2 O. Acidification of the aqueous phase with 2% H 2 SO 4 was followed by extraction with ether. Evaporation of the ether gave 387 mg of a cloudy oil. This was chromatographed on 15 g of silica gel and eluted with 19:1, v:v, benzene:ethanol. About 30 ml of void volume was discarded, then 10 ml fractions were collected.
Fractions 4-18 were combined and evaporated to give 290 mg of a pale yellow oil of the compound of structure Xc (Ic, wherein: T = COOH; T 1 = H; and T 2 = n-C 5 H 11 ) as the nat isomer (Tr. No. 4399: α! D = -45.8; rf = 0.51 in 3:2, v:v, CCl 4 :acetone) having the following physical characteristics:
NMR (CCl 4 ): δ 3.9(1H,bs); 5.4(2H,bs); 7.0(4H,s); 7.2(1H,s)
Mass Spectrum (70 eV) m/e: 386 (M + )
EXAMPLE 48
4-2'{ 3S-hydroxy-1E-octenyl)-5-oxocyclopent-1S-yl!methyl}-phenylbutanoic acid
(11-Deoxy-ent-15-epi-5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ; Tr. No. 4400)
The title compound is secured in the manner of Example 47 when the ent isomer compound of Example 33 (Tr. No. 4267) is employed as the starting compound. Thus hydrolysis of 600 mg of the selected starting compound yielded 200 mg of its acid analogue of the structure Xc (Ic, wherein: T = COOH; T 1 = H; and T 2 = n-C 5 H 11 ) as the ent isomer (Tr. No. 4400: α! D = +41.3; rf = 0.56 in 3:s, v:v, CCl 4 :acetone) having the following physical characteristics:
NMR (CCl 4 ): δ 3.0(1H,bs); 5.5(2H,m); 7.0(4H,s); 7.2(1H,s)
Mass Spectrum (70 eV) m/e: 386 (M + )
EXAMPLES 49-50
ethyl 4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-3R,5S-dihydroxycyclopent-1R-yl methyl}phenylbutanoate
(5,6-dinor-4,7-inter-o-phenyleneprostaglandin F 1 α ethyl ester; Tr. No. 4321)
ethyl 4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-3R,5R-dihydroxycyclopent-1R-yl!methyl}phenylbutanoate
(5,6-dinor-4,7-inter-o-phenyleneprostaglandin F 1 β ethyl ester; Tr. No. 4322)
A solution of 650 mg (0.0015 mol) of 5,6-dinor-4,7-inter-o-phenyleneprostaglandin E 1 ethyl ester (Tr. No. 4309 prepared in the manner of Example 44) in 25 ml of ethanol was cooled to -23° C with stirring. A cold (-23° C) slurry of 1.35 g (0.035 mol) of sodium borohydride in 25 ml of ethanol was added all at once. After 20 minutes the reaction was quenched by adding 1.5 ml acetic acid dissolved in 50 ml H 2 O. 100 ml of ether was added and the mixture stirred for 1 hour. The layers were then separated. The ether phase was washed twice with brine, dried over anhydrous MgSO 4 , and concentrated under reduced pressure to give 480 mg of an oil. This oil was taken up in 10:1:0.006, v:v:v, CHCl 3 : C 2 H 5 OH:H 3 BO 3 and chromatographed on 25 g of silica gel. Elution was with the solvent mixture just described and 1 ml fractions were collected.
Fractions 5 to 10 contained 220 mg of an oil of the compound of structure XVIIIb (If, wherein: T = COOC 2 H 5 ; T 1 = H; and T 2 = n-C 5 H 11 ) as the ent (9-epi) isomer (Tr. No. 4322: α! D = -1.78; rf = 0.22 in 100:1)0.006, v:v:v, CHCl 3 :C 2 H 5 OH:H 3 PO 3 ) having the following physical characteristics:
NMR (CCl 4 ): δ 4.1(2H,q); 5.4(2H,m); 7.1(4H,s)
Mass Spectrum (70 eV) m/e: 414 (M + )
Fractions 13 to 20 contained 230 mg of an oil of the compound of structure XVIIIb (If, wherein: T = COOC 2 H 5 ; T 1 = H; and T 2 = n-C 5 H 11 ) as the nat isomer (Tr. No. 4321: α! D = +20.3; rf = 0.16 in 10:1:0.006, v:v:v, CHCl 3 :C 2 H 5 OH:H 3 PO 3 .
EXAMPLES 51-52
ethyl 4-2'-{ 2S-(3S-hydroxy-1E-octenyl)-3S,5S-dihydroxycyclopent-1S-yl!methyl}phenylbutanoate
(ent-15-epi-5,6-dinor-4,7-inter-o-phenyleneprostaglandin F 1 β ethyl ester; Tr. No. 4323)
ethyl 4-2'-{ 2S-(3S-hydroxy-1E-octenyl)-3S,5R-dihydroxycyclopent-1S-yl!methyl}phenylbutanoate
(ent-15-epi-5,6-dinor-4,7-inter-o-phenyleneprostaglandin F 1 α ethyl ester: Tr. No. 4324)
300 mg of the ent isomer compound of structure XIIb (Tr. No. 4318) prepared according to Examples 41-44 was reduced according to the procedure of Examples 49-50 to give 100 mg of oil of the compound of structure XVIIIb (If, wherein: T = COOC 2 H 5 ; T 1 =H; T 2 = n-C 5 H 11 ) as the 9,15-epi-ent isomer (Tr. No. 4323: α! D = -3.39; rf=0.27 in 10:1:0.06, v:v:v, CHCl 3 : C 2 H 5 OH:H 3 PO 3 ) having the following physical characteristics:
NMR (CCl 4 ): δ 4.0(2H,q); 5.4(2H,m); 7.0(4H,s)
Mass Spectrum (70 eV) m/e: 414 (M + )
Also yielded was 200 mg. of oil of structure XVIIIb, as above, but as the 15-epi-ent isomer (Tr. No. 4324: α! D = +16.05; rf=0.20 in 10:1:0.06, v:v:v, CHCl 3 :C 2 H 5 OH:H 3 PO 3 ).
EXAMPLE 53
4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-3R,5S-dihydroxycyclopent-1R-yl!methyl}phenylbutanoic acid
(5,6-dinor-4,7-inter-o-phenyleneprostaglandin F 1 α : Tr. No. 4428)
One hundred mg of the nat isomer of Examples 49-50 was hydrolyzed by the procedure of Example 47 to prepare 70 mg of the desired acid of structure XVIIIc (If, wherein: T = COOH; T 1 = H; and T 2 = n-C 5 H 11 ) as the nat isomer (Tr. No. 4428: α! D = -22.6; rf = 0.12 in 10:1:0.06, v:v:v, CHCl 3 : C 2 H 5 OH:H 3 PO 3 ) having the following physical characteristics:
NMR (CDCl 3 ): δ 5.3(2H,bd); 7.1(4H,s)
Mass Spectrum (70 eV) m/e: 386 (M + -H 2 O)
EXAMPLE 54
4-2'-{ 2R-(3S-hydroxy-1E-octenyl)-5-oxo-3-cyclopenten-1R-yl!methyl}phenylbutanoic acid
(5,6-dinor-4,7-inter-o-phenyleneprostaglandin A 1 ; Tr. No. 4410)
One hundred mg of the nat isomer of structure XIXb of Examples 41-44 (Tr. No. 4310) was emulsified in 8 ml of 10% gum arabic and placed in a water bath at 37° C. To this was added 0.6 ml of 20% aqueous sodium deoxycholate solution and the pH adjusted to 7.8 with 0.1 N NaOH. Then 100 mg of the enzyme hog pancreatic lipase in 2 ml H 2 O was added. The pH of the reaction was maintained at 7.8 by the addition of 0.1 N NaOH as needed during the first hour. After one hour, 100 mg of fresh enzyme was added and the reaction allowed to stir overnight. The pH was then adjusted to 3.0 with 10% HCl and the mixture extracted with chloroform. The chloroform extract was dried over anhydrous MgSO 4 and concentrated under reduced pressure to give an oil. This was chromatographed on 10 g of silica gel and eluted with 9:1, v:v, CCl 4 :acetone. Two-ml fractions were collected.
Fractions 48 to 78 yielded 80 mg of the desired acid of structure XIXc (Ie, wherein: T = COOH; T 1 = H; T 2 = n-C 5 H 11 ) as the nat isomer (Tr. No. 4410; α! D = +35.1; rf = 0.05 in 4:1, v:v, CCl 4 :acetone) having the following physical characteristics:
NMR (CCl 4 ): δ 5.2(2H,m); 7.1(4H,m); 7.2(1H,m)
Mass Spectrum (70 eV) m/e: 384 (M + )
EXAMPLE 55
Compounds of the invention exhibit selective biological activities and were evaluated, inter alia, for their effect on human platelet aggregation in vitro.
The ability of test compounds to inhibit platelet aggregation was determined by a modification of the turbidometric technique of Born Nature, 194:927 (1962)!. Blood was collected from human volunteers who had not ingested aspirin or aspirin-containing products within the preceding two weeks in heparinized containers and was allowed to settle for one (1) hour. The platelet rich plasma (prp) supernates were collected and pooled. Siliconized glassware was used throughout.
In a representative assay 1.9 ml of PRP and 0.2 ml of test compound at the appropriate concentration (0.001 to 100 mc/gm), or 0.2 ml of distilled water (control procedure) were placed in sample cuvettes. The cuvettes were placed in a 37° C incubation block for 15 minutes, and then in a spectrophotometer linked to a strip chart recorder. After 30-60 seconds, 0.2 ml of a solution, prepared by diluting a calf-skin collagen solution 1:9 with Tyrodes' Solution, was added to each cuvette. Platelet aggregation was evidenced by a decrease in optical density.
Calculation of the degree of inhibition of platelet aggregation exhibited by each concentration of test compound was accomplished according to the method of Caprino et al., Arzneim-Forsch., 23:1277 (1973)!. An ED 50 value was then determined graphically. Activity of the compounds was scored as follows: ,
______________________________________ED.sub.50 (mcg/kg) Activity Value______________________________________ >1.0 0>0.1 <1.0 1>0.1 ≦0.1 2______________________________________
Table H summarizes the results of the preceding screen using the preferred examples.
TABLE H______________________________________Summary of Biological Activity Screenfor Platelet Aggregation Activity ValueTR Example PlateletNo. No. Aggregation______________________________________4211 27 14212 28 14213 29 14214 30 14230 31 14231 32 14310 41 14311 42 14410 54 14269 45 04297 46 14250 25 14251 26 14730 26A4309 44 14318 43 14266 34 14267 33 14302 37 14303 36 14304 39 14305 38 14399 47 14400 48 14513 40 14321 49 14323 51 14322 50 14324 52 14428 53 --4298 35 1______________________________________ | Disclosed are prostaglandin analogues having the structural formula, ##STR1## in which: T is selected from the group consisting of carboxyl, alkoxycarbonyl or cyano;
M is selected from the group consisting of carbonyl, R-hydroxymethylene or S-hydroxymethylene;
L is selected from the group consisting of methylene or methine, provided L is methine only if J is methine;
J is selected from the group consisting of methylene, ethylene, R-hydroxymethylene, S-hydroxymethylene or methine, provided J is methine only if L is methine;
W is selected from the group consisting of --CH 2 --CH-- or trans --CH═C--;
T 1 and T 2 are attached to adjacent carbon atoms;
T 1 is selected from the group consisting of hydrogen or phenyl, provided T 1 is phenyl only if T 2 is lower alkyl;
T 2 is selected from the group consisting of n-pentyl or lower alkyl, provided T 2 is lower alkyl only if T 1 is phenyl;
Or T 1 and T 2 are joined together to form an alkylene group of 4 or 6 carbon atoms. Also disclosed are methods for preparing such prostaglandin analogues. | 2 |
RELATED APPLICATIONS
[0001] This patent claims priority from U.S. Provisional Application Ser. No. 61/289,958 entitled “A simple and efficient early stop scheme for turbo decoder” which was filed on Dec. 23, 2009; U.S. Provisional Application Ser. No. 61/292,801 entitled “A UMTS turbo decoder with multiple MAP engines” which was filed on Jan. 6, 2010; U.S. Provisional Application Ser. No. 61/289,921 entitled “A method of trellis termination handling in turbo decoder” which was filed on Dec. 23, 2009; and U.S. Provisional Application Ser. No. 61/301,046 entitled “A contention free memory structure and interleaver for parallel HSPA_LTE turbo decoder” which was filed on Feb. 3, 2010. Each of U.S. Provisional Patent Application Ser. Nos. 61/289,958, 61/292,801, 61/289,921 and 61/301,046 is hereby incorporated by reference in its entirety.
FIELD OF THE DISCLOSURE
[0002] This disclosure relates generally to receivers for communication systems, and, more particularly, to methods and apparatus to perform turbo decoding for communications receivers.
BACKGROUND
[0003] Communications Systems widely adopt error correction coding techniques to combat with error introduced by interference and noise. FIG. 1 illustrates a typical communication system with error correction techniques which comprises an error correction encoder 100 at transmitter and a decoder 110 at receiver. The class of error control codes, referred to as turbo codes, offers significant coding gain for power limited communications channels.
[0004] Turbo codes are decoded by iterative decoding algorithms. It belongs to a family of iterative decoding algorithms applicable to LDPC code, turbo product code, parallel concatenated convolutional code, serial concatenated convolutional code and etc. During each iteration, the decoder improves the reliability of the information bits. In order to reach a sufficient decoding performance, usually a fixed number of iteration is used. However, in many cases, the correct decoding results can be generated with only a few iterations. Excessive iteration does not help to improve the performance further and only consumes extra power which is a critical resource in mobile devices.
[0005] Many early stop algorithms have been proposed to reduce the power consumption for turbo decoding. These algorithm claims to have good performance but these studies did not looked into practical scenarios where the code rate is high. For example, a hard-decision comparison based algorithm has been proposed in [1]. This algorithm compares hard-decisions of information bits from the current iteration and that of the previous iteration. The decoding is stopped once the hard-decisions from the previous iteration matches with those of the current iteration. This algorithm introduces large performance loss in high SNR channel conditions especially with the combination of high code rate. This made the algorithm difficult to be implemented into a practical communication system since the practical communication system like HSDPA usually applies high code rate when signal to noise ration is sufficient. Another early stop algorithm [1] has been proposed which computes the minimum log likelihood ratio (LLR) of decoded output bits. If the minimum value of LLR of all bits exceeds the certain threshold, the decoding is stopped. However, a large block error rate (BLER) performance loss is reported when channel SNR is high. Among various early stop algorithms proposed, no sufficient investigation in the literature has been found to explore the relationship between the BLER performance loss and code rate.
[0006] [1] A. Matache, S. Dolinar and F. Pollara, “Stopping Rules for Turbo Decoders”, TMO Progress Report 42-142, Jet Propulsion Laboratory, Aug. 15, 2000.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a communications system with error correction coding.
[0008] FIG. 2 is a block diagram of turbo code.
[0009] FIG. 3 illustrates an iteration decoding algorithm for turbo codes.
[0010] FIG. 4 illustrates the early stop algorithm invented.
[0011] FIG. 5 illustrates the performance of early stop algorithm in low code rate.
[0012] FIG. 6 illustrates the performance of early stop algorithm in high code rate.
DETAILED DESCRIPTION
[0013] As illustrated in FIG. 2 , turbo codes consist of two constituent recursive convolutional codes. The information bits are first encoded by a recursive systematic convolutional encoder 210 , and the interleaved version 220 of the information bits are encoded again by the same type of convolutional encoder 230 . The resultant parity bits of the first encoder, the second encoder and the systematic information bits itself are transmitted over the communications channels.
[0014] The decoding algorithm of turbo codes is known as iterative decoding algorithm. The block diagram of an example iterative decoding algorithm is illustrated in FIG. 3 . In a decoding iteration, two soft-input, soft-output decoders are employed. The output of the first decoder 300 is feed into the second decoder as input after interleaving. Similarly, the output of the second decoder 320 is feed into the first decoder as input. A decoding iteration is completed by passing information once between the DEC- 1 300 to DEC- 2 320 and DEC- 2 320 to DEC- 1 310 . For each soft-input soft-output decoder, the MAP decoding algorithms which generates maximum a posterior probability of the information bits are usually used. The MAP decoder takes soft input of systematic bits, and parity bits. It computes the soft-output of the systematic bits using the trellis structure of the convolutional code. The soft-output is called a posterior information. At the same time, the extrinsic information is also calculated which is defined as the contribution of information from the current decoding process alone. The extrinsic information is de-interleaved before passing to the next decoding stage. In the next decoding stage, the extrinsic information is utilized as a priori information of the systematic bits and added together with the systematic information bits before decoding. This type of iteration is repeated multiple times before the final results are given as the output. To achieve a good performance of turbo decoding, multiple decoding iterations are required. But the number of iteration depends on the signal to noise ratio (SNR) of the channel. In a low SNR scenario, more iteration, typically 8 to 16 is usually required. However, in high SNR scenarios, the number of iteration can be largely reduced.
[0015] In cellular communication systems, the turbo code is adopted for many standards. The WCDMA standard, the CDMA2000 standard and the WiMAX standard have adopted turbo code as forward error correction techniques. In the case of mobile devices which usually powered by batteries, the power consumption is an important factor. For high data rate communication applications, the turbo decoder consumes significant percentage of total amount of power of a mobile device. Therefore, reducing power consumption by early stopping the turbo decoding iterations without error rate performance degradation is critical.
[0016] In this disclosure, a new algorithm is proposed to reduce the number of iterations without observable performance loss in BLER. This algorithm as illustrated in FIG. 4 is a combination of the following two approaches.
[0017] For each half iteration number (i), the hard-decisions are stored and compared with the hard-decisions from the previous iteration (i−2). No comparison is performed between two consecutive half iterations due to the fact that these information bits are generated in the interleaved order. For two consecutive half iterations (i) and (i+1), if both of them have matched hard-decisions with their previous iteration results respectively, i.e., half iteration (i) matched with (i−2) and half iteration (i−1) matched with (i−3). The first stop criterion is met. This stop criterion is found to perform well in low code rate but showing significant performance loss in high code since no sufficient extrinsic information is provided from highly punctured parity bits therefore hard decision may not change between consecutive iterations.
[0018] The minimum log likelihood ratio (LLR) of all output bits are computed and compared with a threshold K. If the minimum reliability of the output bits exceeds the threshold K. Then the second stop criterion is met. This stop criterion is found to provide limited performance in high SNR scenario but is good in high code rate cases.
[0019] For each half iteration, the decoding is stopped when both stop criterions are met therefore.
[0020] Extensive computer simulation has been performed to check the performance of the disclosed algorithm to cover different code rate from ⅓ to 0.99 and different code block sizes. Using the first stopping criteria alone, the BLER performance does not degrade in the low code rate but significant performance loss observed in high code rate. Using the second stopping criteria alone, the BLER performance degradation is significant especially when code rate is low. However, combining these two stopping criteria, the BLER performance loss becomes none observable in any code rate.
[0021] Computer simulation results are given for the disclosed algorithm. The performance loss of BLER is illustrated in FIG. 5 when code rate is low, i.e., r=0.33 and code block size=5114. The performance loss of BLER is illustrated in FIG. 6 when code rate is high, i.e., r=0.98 and code block size=5114. Both cases showing excellent BLER performance of the disclosed algorithm. | Methods and apparatus for early stop algorithm of turbo decoding are disclosed. An example method comprises of combination of comparing of hard decisions of soft outputs of the current iteration and the previous iteration and comparing the minimum log likelihood results against a threshold. The decoding iteration is stopped once the hard decisions are matched and the minimum soft decoding result exceeds a threshold. | 7 |
FIELD OF THE INVENTION
[0001] The present invention generally relates to support pillows, for example, pillows for supporting infants in a person's lap.
BACKGROUND OF THE INVENTION
[0002] Supporting an infant's weight in one's arm becomes tiring after a prolonged period of time. For this reason, and the importance of supporting an infant's head and neck, support pillows are widely used to support an infant in a person's lap, for example during feeding or nursing. These support pillows generally support the infant's head and neck, enabling the infant to more easily access a feeding device.
[0003] Support pillows typically have soft surfaces on which the infants rest, and are generally stuffed with a filler, making the pillow sufficiently firm to support the infant. However, the fabric used for the soft surface of the pillow and the filler used to impart firmness can cause allergic reactions, and the absorbent nature of these materials makes them very difficult to clean. As a result, these pillows attract germs and allergens that may be harmful to the infant resting on the pillow or to the person using the pillow to support the infant.
[0004] Also, existing pillows tend to lose their stiffness over time, particularly if the pillow has been washed. Washing a pillow that has a fabric surface and a filler causes the pillow to flatten, often reducing stiffness by as much as 30% after a single washing, and eventually the pillow must be replaced.
[0005] In addition, support pillows are generally U-shaped, often fitting very snugly around an adult's waist. However, these U-shaped pillows are typically not well-suited for overweight adults because the pillows tend to fit too tightly around the person's waist, making it very uncomfortable to support an infant in the person's lap. Accordingly, a need exists for an infant support pillow that can be hypo-allergenic, easy to clean and suitable for use by overweight adults.
SUMMARY OF THE INVENTION
[0006] The present invention is directed to support pillows which can be used to support infants in a person's lap, for example during feeding. In one embodiment, the pillow is generally L- or V-shaped and has first and second arms extending from a main pillow body. The first and second arms of the pillow may be the same length or may have different lengths.
[0007] In one embodiment, the support pillow is inflatable and is constructed of a material that is substantially impermeable to air and/or fluid. The pillow according to this embodiment is inflated through a valve, and can be inflated to any desired pressure and stiffness. Also, the pillow may be re-inflated if it loses pressure or stiffness, eliminating the need to replace a flattened pillow.
[0008] In another embodiment, the support pillow is made of a hypo-allergenic material. The hypo-allergenic material may be an inflatable material, and may have a smooth surface to enable easy cleaning of the pillow. In yet another embodiment, the pillow may further comprise a cover, which may be made of a hypo-allergenic material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] These and other features and advantages of the present invention will be better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, wherein:
[0010] FIG. 1A is a top view of a support pillow according to one embodiment of the present invention;
[0011] FIG. 1B is a bottom view of the support pillow of FIG. 1B ;
[0012] FIG. 1C is a top view of a support pillow according to another embodiment of the present invention;
[0013] FIG. 1D is a top view of a support pillow according to yet another embodiment of the present invention;
[0014] FIG. 2A is an elevated side view of a support pillow according to one embodiment of the present invention;
[0015] FIG. 2B is an elevated side view of the opposite side of the support pillow of FIG. 2A ;
[0016] FIG. 3A is a schematic illustrating a method of manufacturing a support pillow according to one embodiment of the present invention;
[0017] FIG. 3B is a schematic illustrating a method of manufacturing a support pillow according to another embodiment of the present invention;
[0018] FIG. 3C is a schematic illustrating a method of manufacturing a support pillow according to yet another embodiment of the present invention;
[0019] FIG. 4 is a top view of a support pillow according to an alternative embodiment of the present invention;
[0020] FIG. 5 is a top view of a support pillow according to another alternative embodiment of the present invention;
[0021] FIG. 5 a is a top view of a support pillow according to yet another alternative embodiment of the present invention;
[0022] FIG. 6 is a schematic depicting one use of a support pillow according to one embodiment of the present invention; and
[0023] FIG. 7 is a schematic depicting an alternative use of a support pillow according to one embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0024] In one embodiment, as shown in FIGS. 1A, 1B , 2 A and 2 B, a support pillow 9 comprises a first arm 12 and a second arm 14 connected by a main pillow body. In accordance with the invention, one arm is adapted to rest on a person's lap while the other arm extends along one side of the person's waist, leaving the other side of the person's waist and the person's back generally free of contact from the pillow. As such, the pillow of the present invention is comfortable and suitable for use by a person regardless of his or her size. In the illustrated embodiment of FIG. 1 , the first and second arms 12 and 14 protrude from the main pillow body to form a generally V-shaped pillow. Also in this embodiment, the first and second arms 12 and 14 have substantially the same length.
[0025] The pillow 9 may be made of any suitable material. In one embodiment, the pillow 9 is inflatable with either air or fluid and is made of a high gauge rubber that is substantially impermeable to air and/or fluid. A nonlimiting example of such a rubber is butyl rubber, which is commonly used for inner tubes and air cushions. The pillow may also be made of an inflatable plastic. A nonlimiting examples of such a plastic is vinyl, such as 16 gauge vinyl, which is commonly used for wading pools. These inflatable pillows are also easily deflated to conserve storage space. In addition to being inflatable, pillows made of this rubber are easily cleaned, for example, with a damp cloth. Also, pillows made of this rubber will not accumulate germs and/or allergens from the surrounding environment as readily as a cloth or fabric pillow.
[0026] As shown in FIG. 1B , the pillow 9 is inflated by forcing air or fluid through a valve 36 . This allows the firmness of the pillow 9 to be adjusted by varying the degree of inflation. The valve enables inflation by any suitable means. For example, a user may inflate the pillow by blowing air from his or her mouth into the pillow through the valve. Alternatively, a bicycle pump or similar device may be used to pump air to the pillow through the air valve. Also, fluid can be inserted into the pillow through the valve either through a funnel or similar device, or by a pump.
[0027] In an alternative embodiment, the pillow 9 is made of a hypo-allergenic material, which can be a cloth or fabric. In this embodiment, the pillow may also be filled with a hypo-allergenic filler.
[0028] Alternatively, the pillow may further comprise a cover, which may be made of any suitable material, including a hypo-allergenic material. In this embodiment, the pillow is easily cleaned by washing the pillow cover. Because only the cover of the pillow is washed, the pillow will not flatten due to washing.
[0029] The main pillow body 10 comprises sides 10 a , 10 b , and 10 e . The first and second sides 10 a and 10 b converge at location A. An angle α between the generally linear first and second sides 10 a and 10 b is about 90°, but can be less than 90°. The third side 10 e is generally arcuate and opposes location A. A distance between the side 10 e and the location A may range between about 14 to about 25 inches, preferably from about 15 to 22 inches, and more preferably from about 15 to about 19 inches. The first arm 12 of the pillow extends along the first side 10 a , and the second arm 14 extends along the second side 10 b.
[0030] As shown in FIG. 1A , the location A may be a corner configuration, or as shown in FIG. 1B , an arcuate configuration so long as the pillow remains generally V-shaped. Similarly, free ends 11 and 13 of the first and second arms 12 and 14 , respectively can take any suitable shape. For example, the free ends 11 and 13 of the first and second arms 12 and 14 , respectively, may be substantially square, as shown in FIGS. 1A and 1B , or substantially rounded, as shown in FIG. 1C .
[0031] The lengths of the first and second arms 12 and 14 are not critical and can vary as desired. In one embodiment, length d 1 of each of the arms ranges from about 15 to about 30 inches. In addition, the arms 12 and 14 can have any widths and circumferences as desired. In addition, the pillow 9 can take any suitable cross-sectional shape, including but not limited to circular, ovular, square and rectangular shapes. In one embodiment, the width d 2 of each of the arms 12 and 14 ranges from about 8 to about 15 inches, and the circumferences of the arms 12 and 14 (when inflated or stuffed to the desired degree) range from about 22 to about 30 inches.
[0032] In another exemplary embodiment, as shown in FIG. 4 , the support pillow 109 comprises a main pillow body 110 and first and second arms 112 and 114 , respectively. The first and second arms 112 and 114 protrude from the main pillow body 110 to form a generally L-shaped pillow. In this embodiment, the first arm 112 is shorter than the second arm 114 .
[0033] Like the pillow 9 , the pillow 109 may be made of any suitable material. In one embodiment, the pillow 109 is inflatable and made of a high gauge rubber that is substantially impermeable to air. A nonlimiting example of such a rubber is butyl rubber, which is commonly used for inner tubes and air cushions. The pillow may also be made of an inflatable plastic. A nonlimiting examples of such a plastic is vinyl, such as 16 gauge vinyl, which is commonly used for wading pools. These inflatable pillows are also easily deflated to conserve storage space. In addition to being inflatable, pillows made of this rubber are easily cleaned, for example, with a damp cloth. Also, pillows made of this rubber will not accumulate germs and/or allergens from the surrounding environment as readily as a cloth or fabric pillow.
[0034] Like the pillow 9 , the pillow 109 is inflated by forcing air through an air valve (not shown). This allows the firmness of the pillow 109 to be adjusted by varying the degree of inflation. The air valve enables inflation by any suitable means. For example, a user may inflate the pillow by blowing air from his or her mouth into the pillow through the air valve. Alternatively, a bicycle pump or similar device may be used to pump air to the pillow through the air valve. The air valve may be placed in any suitable location on the pillow 109 , including on the bottom of the pillow, away from the surface of the pillow on which an infant may rest.
[0035] In an alternative embodiment, the pillow 109 is made of a hypo-allergenic material, which can be a cloth or fabric, such as cotton or polyester. In this embodiment, the pillow may also be filled with a hypo-allergenic filler, such as polyester.
[0036] Like the main pillow body 10 , the main pillow body 110 comprises sides 110 a , 110 b , and 110 e . The first and second sides 110 a and 110 b converge at location B. An angle β between the generally linear first and second sides 110 a and 110 b is about 90°, but can be less than 90°. The third side 110 e is generally arcuate and opposes location B. A distance between the side 110 e and the location B may range between about 14 to about 25 inches, preferably from about 15 to 22 inches, and more preferably from about 15 to about 19 inches. The first arm 112 of the pillow extends along the first side 110 a , and the second arm 114 extends along the second side 110 b.
[0037] As shown in FIG. 4 , the location B may be a corner configuration, or as shown in FIG. 5 , an arcuate configuration, so long as the pillow remains generally L-shaped. Similarly, free ends 111 and 113 of the first and second arms 112 and 114 , respectively can take any suitable shape. For example, the free ends 111 and 113 of the first and second arms 112 and 114 , respectively, may be substantially square, as shown in FIG. 4 , or substantially rounded, as shown in FIG. 5 .
[0038] The lengths of the first and second arms 112 and 114 are not critical and can vary as desired. However, the first arm 112 is longer than the second arm 114 . In one embodiment, the length d 4 of the first arm ranges from about 15 to about 30 inches. The second arm 114 may have any length sufficient to support the arm 114 against the side of a person's body. For example, the second arm 114 may have a length d 3 ranging from about 8 inches to about 20 inches. Also, the pillow 109 can take any suitable cross-sectional shape, including, but not limited to, circular, ovular, square and rectangular shapes. In addition, the arms 112 and 114 can have any width and circumference as desired. In one embodiment, the width d 5 of the each of the arms 112 and 114 ranges from about 8 to about 15 inches, and the circumference of each arm 112 and 114 (when inflated or stuffed to the desired degree) ranges from about 22 to about 30 inches.
[0039] As shown in FIG. 3A , the pillows 9 and 109 may be fabricated according to one embodiment by connecting two generally identically configured pieces of material 56 and 58 with a seam 60 (shown in FIGS. 2A and 2B ). Each piece has the main pillow body and both arms. The seam 60 spans the entire perimeter of the pillows 9 and 109 . Although the pillows 9 and 109 are described as being fabricated by connecting two pieces of material 56 and 58 with a seam 60 , it is understood that any means of fabricating the pillow may be used. For example, as shown in FIG. 3B , the pillow may be fabricated from one piece of material with two mirroring halves 56 a and 58 a that are bridged 59 at a free end of an arm. The two halves are folded over on each other and then connected by the seam 60 extending generally the perimeter around the bridged free end. Alternatively, as shown in FIG. 3C , the main pillow body 10 or 110 and the arms 12 and 14 or 112 and 114 can be fabricated separately and the arms connected to the main pillow body with connecting seams 62 and 64 between the arms and the main pillow body.
[0040] The pillows 9 and 109 may also include handles 30 for carrying, gripping or repositioning the pillows. The handle 30 can be constructed of any suitable material, and can be made of the same material as the pillow or a different material. As shown, the handle 30 is attached to the pillow at the seam 60 . However, it is understood that the handle 30 may be attached in any suitable manner. In inflatable embodiments, the handle 30 should be attached such that the attachment does not substantially affect the impermeability of the pillow to air.
[0041] In addition, the handle 30 may be located anywhere on the pillow. For example, as shown in FIGS. 1A, 1B and 4 the handle can be connected at one end to a side of the main pillow body and connected at the other end to one of the arms. Alternatively, as shown in FIGS. 1C, 2B and 5 , both ends of the handle can be connected to one of the arms. In another alternative, both ends of the handle can be connected to one side of the main pillow body, or one end can be connected to the first side 10 a or 110 a and the other end connected to the second side 10 b or 110 b of the main pillow body (shown in FIG. 1D ).
[0042] The pillows 9 and 109 may further comprise at least one pocket 120 positioned on one or both of the arms, as shown in FIG. 5 a . The pocket 120 may have any suitable shape and size and may be positioned anywhere on the arms. In addition, the pocket 120 may have an open top 121 adapted to receive various items, such as burp cloths or bottles (when the pillow is used to feed an infant). Alternatively, the pocket 120 may have a reversibly closeable top 122 , such as a zipper, Velcro® or the like. The pillows 9 and 109 may have any number of pockets 120 as desired, and a plurality of pockets 120 may be positioned on all sides of the pillow to provide at least one pocket 120 regardless of which side of the pillow is being used.
[0043] In use for supporting an infant, as shown in FIG. 6 , one of the arms of the pillow spans the lap of a person using the pillow, and the other arm rests against the side of the person's body. Neither arm wraps around the back of the person's body. However, it is understood that the pillow can be used for purposes other than infant support, such as back support. When used, for example for back support, one arm of the pillow may span the back of a person's body, and the other arm rests against the side of the person's body, as shown in FIG. 7 . The L- and V-shaped configurations of the inventive pillows makes them considerably more comfortable for overweight persons than existing U-shaped infant support pillows.
[0044] The preceding description has been presented with references to certain exemplary embodiments of the invention. However, workers skilled in the art and technology to which this invention pertains will appreciate that alterations and modifications in the described structure may be practiced without meaningfully departing from the principal, spirit and scope of the invention. Accordingly, the foregoing description should not be read as pertaining only to the described embodiments, but rather should be read consistent with and as support for the following claims, which are to have their fullest and fairest scope. | A support pillow for supporting infants, for example during feeding, is provided. The support pillow takes a shape selected from the group consisting of V-shapes and L-shapes. the support pillow comprises first and second arms extending from a main pillow body. The support pillow can be inflatable and made of a rubber or plastic material. Alternatively, the support pillow can be made of a hypo-allergenic material. | 0 |
BACKGROUND
[0001] This invention relates to a system and method of estimating body states of a vehicle.
[0002] Dynamic control systems have been recently introduced in automotive vehicles for measuring the body states of the vehicle and controlling the dynamics of the vehicle based on the measured body states. For example, certain dynamic stability control systems know broadly as control systems compare the desired direction of the vehicle based on the steering wheel angle, the direction of travel and other inputs, and control the yaw of the vehicle by controlling the braking effort at the various wheels of the vehicle. By regulating the amount of braking torque applied to each wheel, the desired direction of travel may be maintained. Commercial examples of such systems are known as dynamic stability program (DSP) or electronic stability program (ESP) systems.
[0003] Other systems measure vehicle characteristics to prevent vehicle rollover and for tilt control (or body roll). Tilt control maintains the vehicle body on a plane or nearly on a plane parallel to the road surface, and rollover control maintains the vehicle wheels on the road surface. Certain systems use a combination of yaw control and tilt control to maintain the vehicle body horizontal while turning. Commercial examples of these systems are known as active rollover prevention (ARP) and rollover stability control (RSC) systems.
[0004] Typically, such control systems referred here collectively as dynamic stability control systems use dedicated sensors that measure the yaw or roll of the vehicle. However, yaw rate and roll rate sensors are costly. Therefore, it would be desirable to use a general sensor to measure any body state of the vehicles, that is, a sensor that is not necessarily dedicated to measuring the roll or yaw of the vehicle.
BRIEF SUMMARY OF THE INVENTION
[0005] In general, the present invention features a system and method for estimating body states of a vehicle. The system includes at least two sensors mounted to the vehicle. The sensors generate measured signals corresponding to the dynamic state of the vehicle. A signal adjuster or signal conditioner transforms the measured vehicle states from a sensor coordinate system to a body coordinate system associated with the vehicle. A filter receives the transformed measured vehicle states from the signal adjuster and processes the measured signals into state estimates of the vehicle, such as, for example, the lateral velocity, yaw rate, roll angle, and roll rate of the vehicle.
[0006] The filter may include a model of the vehicle dynamics and a model of the sensors such that the states estimates are based on the transformed measured signals and the models of the vehicle dynamics and sensors. The filter may also include an estimator implemented with an algorithm that processes the transformed measured vehicle states and the models of the vehicle dynamics and sensors and generates the state estimates.
[0007] The present invention enables measuring the body states of a vehicle with various types of sensors that may not be as costly as dedicated roll or yaw rate sensors. For example, the sensors may all be linear accelerometers. However, in some implementations, it may be desirable to use an angular rate sensor in combination with linear accelerometers.
[0008] Other features and advantages will be apparent from the following drawings, detailed description and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 depicts a block diagram of the processing of the vehicle states in accordance with the invention.
[0010] FIG. 2 depicts a general array of sensors for measuring body states of a vehicle.
DETAILED DESCRIPTION
[0011] In accordance with an embodiment of the invention, FIG. 1 illustrates a system 10 that measures the vehicle states of a vehicle identified as block 12 . Specifically, the system 10 includes a plurality of sensors 14 that measure signals which contain parts related to components of the vehicle states of the vehicle dynamics 16 produced, for example, when the angle of the steering wheel δ is changed.
[0012] The system 10 also includes a signal conditioner or adjuster 18 that receives measured signals from the sensors 14 and a filter 20 that receives the adjusted signals from the signal adjuster 18 . In certain embodiments, the filter 20 is a Kalman filter including a model of the vehicle dynamics 22 and a model of the sensors 24 . These models are described below in greater detail.
[0013] The signal adjuster 18 and the sensor model 24 , which incorporates the model of the vehicle dynamics 22 , provide inputs to an estimator 26 . An algorithm with a feed back loop 28 is implemented in the estimator 26 to process the transformed signals with the models of the vehicle dynamics and the sensors. The output from the estimator 26 is the state estimates {right arrow over (x)} v . The body states estimates may include the roll angle, roll rate, yaw rate, and lateral velocity, as well as other body states.
[0014] In some embodiments, the sensors 14 measure the linear acceleration at a particular location where the sensor is mounted to the vehicle. When the sensors are not aligned in a plane perpendicular to the axis of interest, the measured values contain biases proportional to the angular rates about other axes. Similarly, when the measurement axes of the sensing devices are not coincident, the measured values contain biases proportional to the angular acceleration about other axes. Moreover, when the measurement axes of the sensing devices are not coincident and are not mounted along a body reference axis, the measured values contain unique gravity biases dependent upon the difference in mounting angle of the sensors and the body lean angle of the vehicle.
[0015] To address these biases, a general implementation of the system 10 can be employed as illustrated in FIG. 2 . Here the sensors 14 (identified individually as S 1 and S 2 ) are in known and fixed positions on the vehicle body 12 and the orientation of the measurement axes of the sensors S 1 and S 2 are known and fixed. Specifically, the location and orientation of a sensor S i is provided by the relation
P i (x i , y i , z i , θ i , χ i , φ i ), (1)
where x i , y i , z i are the space coordinates of the sensor S i , θ i is the sensor yaw angle, that is, the orientation of the sensor's measurement axis in the X B , Y B plane with respect to the X B axis, χ i is the sensor pitch angle, that is, the orientation of the sensor's measurement axis with respect to the X B , Y B plane, and φ i is the sensor roll angle, which is the rotation about the respective measurement axis.
[0016] The sensors S i measure the linear acceleration at the location Pi, namely, {right arrow over (α)} i ={right arrow over (m)} i ·|m i |=[α xi , α yi , α zi ] T , where {right arrow over (m)} i is the unit vector along the measurement axis, and |m i | is the magnitude of the acceleration along the measurement axis.
[0017] Since the acceleration {right arrow over (α)} i measured by the sensor S i is the acceleration in the sensor coordinate system, the measured accelerations are transferred to a body coordinate system. In certain embodiments, it is assumed that in an array of single axis accelerometers each accelerometer has a measurement axis referred to as the x sensor axis. Accordingly, the transformation from the sensor coordinate system to the body coordinate system is provided by the expression
a ⇀ i × Body _ i = a ⇀ i [ x body , i y body , i z body , i ] = [ a x , body a y , body a z , body ] where Body _ i = [ x body , i y body , i z body , i ] = [ θ i c χ i c - θ i s ϕ i c - θ i c χ i s ϕ i s θ i s ϕ i s + θ i c χ i s ϕ i c θ i s χ i c θ i c ϕ i c + θ i s χ i s ϕ i s - θ i c ϕ i s - θ i s χ i s ϕ i c χ i s χ i c ϕ i s χ i c ϕ i c ] · [ x sensor y sensor z sensor ]
where
_c = cos ( _ )
_s = sin ( _ )
θ i = sensor_yaw _angle
χ i = sensor_pitch _angle
ϕ i = sensor_roll _angle ( 2 )
and [x sensor y sensor z sensor ] T =[1 0 0] T , since x sensor is assumed to be the measurement axis for each of the single axis accelerometers.
[0018] Note that the transformation identified in Equation (2) is typically performed in the signal adjuster 18 ( FIG. 1 ). The signal adjuster 18 may also provide a DC bias offset compensation to compensate for the biases discussed above.
[0019] Regarding the Kalman Filter 20 , the model of the vehicle dynamics 22 for a state vector
{right arrow over (x)} v =[{dot over (y)} v r v θ v {dot over (θ)} v ] T (3)
is provided by the expression
x -> . v = A · x ⇀ v + B · u ⇀ ( 4 ) where [ y ¨ v r . v θ . v θ ¨ v ] = [ - C F + C R mu C R b - C F a mu - u 0 0 C R b - C F a I z u - C F a 2 + C R b 2 I z u 0 0 0 0 0 1 - h I x u h ( C R b - C F a - mu 2 ) I x - K I x - C I x ] [ y . v r v θ v θ . v ] + [ C F m 0 C F a I z 0 0 0 C F m 0 ] [ δ g ] and where
y . v = lateral velocity of the vehicle
r = yaw rate of the vehicle
θ v = roll angle of the vehicle
θ . v = roll rate of the vehicle
C F = cornering stiffness of the front axle
C R = cornering stiffness of the rear axle
a = distance from center of gravity to the front axle
b = distance from center of gravity to the rear axle
m = mass of the vehicle
h = height of the center of gravity
above the roll axis I z = yaw moment of inertia
I x = roll moment of inertia
C = vehicle roll dampening
K = vehicle roll stiffness
u = longitudinal vehicle speed
δ = steering angle of the tires
g = gravitational acceleration
* . = ⅆ ⅆ t *
and * .. = ⅆ 2 ⅆ t 2 ( 5 )
[0020] As for the model of the sensors 24 , the model of laterally oriented sensors is provided by the expression
[0000] A y,meas =ÿ v +{dot over (r)} v d xtoYA +{umlaut over (θ)} v d ztoRA +r v u (6)
[0021] Accordingly, since A y,meas =α y,body from Equation (2), substituting the expressions for ÿ v , {dot over (r)} v , {umlaut over (θ)} v , and r v from Equation (5) into Equation (6) yields the expression
a y , body = [ a 11 y . v + a 12 r v + C F m δ ] + [ a 21 y . v + a 22 r v + C F a I z δ ] d xtoYA + [ a 41 y . v + a 12 r v + a 43 θ v + a 44 θ . v + C F m δ ] d ZtoRA + r v · u = [ a 11 + a 21 d xtoYA + a 41 d ztoRA ] y . v + [ a 12 + a 22 d xstoYA + a 42 d ztoRA + u ] r v + [ a 43 d ztoRA ] θ v + [ a 44 d ztoRA ] θ . v + [ C F m + C F a I z d xtoYA + C F m d ztoRA ] δ ( 7 )
where α kl is the element in the k row and l column of the matrix A, d xtoYA is the distance along the x axis from a sensor to the yaw axis, and d ztoRA is the distance along the z axis from the sensor to the roll axis.
[0022] The model for vertically oriented sensors is
A z,meas =−g+{umlaut over (θ)} v d yraRA (8)
Hence, from Equations (2) and (5)
a z , body = - g + [ a 41 y . v + a 42 r v + a 43 θ v + a 44 θ . v + C F m δ ] d ytoRA = ⌊ a 41 d ytoRA ⌋ y . v + ⌊ a 42 d ytoRA ] r v + ⌊ a 43 d ytoRA ] θ v + [ a 44 d ytoRA ] θ . v + [ C F m d ytoRA ] δ + [ - g ] ( 9 )
where d ytoRA is the distance along the y axis to the roll axis.
[0023] And for longitudinally oriented sensors, the sensor model is provided by the expression
A x,meas =−{dot over (r)} v d ytoYA (10)
such that upon employing Equations (2) and (5), Equation (10) becomes
a x , body = - a 21 d dtoYA y . - a 22 d dytoYA r v - b 21 d ytoYA δ ( 11 )
where d dytoYA is the distance along the y axis to the yaw axis and b 21 is the element in the second row and first column of the matrix B.
[0024] The algorithm implemented in the estimator 26 processes the expressions from Equations (7), (9), and (11) through a filter (an estimation algorithm) to provide the estimates for the state vector {right arrow over (x)} v =[{dot over (y)} v r v θ v {dot over (θ)} v ] T .
[0025] Note that the above discussion is directed to obtaining a solution for the state vector {right arrow over (x)} v in continuous time. Therefore, {right arrow over (x)} v , is typically discretized according to the expression
{right arrow over (x)} v ( k+ 1)= A d {right arrow over (x)} v ( k )+ B d {right arrow over (u)}( k ) (12)
where k identifies the k th time step and the matrices A and B can be discretized according to the approximations
A d =I n +Δ k ·A
and
B d =Δ k ·B
where I n is the nth order identity matrix, which in this case is a fourth order identity matrix, and Δ k is the time step.
[0026] Although the above embodiment is directed to a sensor set with linear accelerometers, hybrid-sensor-sets are contemplated. For example, an angular rate sensor can be used in the vehicle 12 and a model of that sensor can be used in the “Kalman Filter” box 20 . Specifically, for a yaw rate sensor, the model is [0 1 0 0], that is, the sensor measures yaw rate and nothing else.
[0027] Hence, in stability control, in which measuring yaw rate and roll rate/angle is useful, four accelerometers can be used for the sensors 14 . Alternatively, for a hybrid system, two accelerometers and an angular rate sensor may be employed. Other examples of hybrid systems include, but are not limited to, two lateral and two vertical accelerometers; two lateral, two longitudinal, and two vertical accelerometers; and two lateral, two vertical accelerometers, and an angular rate sensor.
[0028] Other embodiments are within the scope of the claims. | The present invention features a system and method for estimating body states of a vehicle. The system includes at least two sensors mounted to the vehicle. The sensors generate measured vehicle state signals corresponding to the dynamics of the vehicle. A signal adjuster transforms the measured vehicle states from a sensor coordinate system to a body coordinate system associated with the vehicle. A filter receives the transformed measured vehicle states from the signal adjuster and processes the measured signals into state estimates of the vehicle, such as, for example, the lateral velocity, yaw rate, roll angle, and roll rate of the vehicle. | 1 |
FIELD OF THE INVENTION
The present invention relates to a machine that cleans both sides of thin, flexible, and uncarpeted floor mats, including exercise mats such as those used for yoga, pilates, barre, or other similar exercise routines.
BACKGROUND
Participation in fitness activities continues to grow in ever increasing rates. Amongst the largest growth sectors in fitness are yoga, pilates, and barre. Participation in yoga alone has increased at a rate of about 20% per year since 2006 according to the National Sporting Goods Association, or an estimated 20 million Americans. Though some people practice these exercise routines in their own home, many individuals seek out a workout center or studio for instructional purposes.
As part of these exercise routines, participants use a thin, flexible mat to place between themselves and the floor. The mat is typically six (6) feet long by two (2) feet wide and is made from a special plastic-based foam or sometimes rubber. These materials create friction to facilitate the user in performing various moves and exercises. Often, these mats are provided to participants as a courtesy by a gym, workout center, or exercise studio. Many participants decide to purchase their own mat simply because they find another person's sweat unappealing.
These exercise routines are strenuous and cause the body to sweat. This sweat is transferred to the mat during the workout. Sweat contains germs, bacteria, and human bodily wastes. Sometimes, the sweat accumulates so greatly that the user must turn the mat over during the exercise routine because the mat becomes slippery. This exposes the sweaty side of the mat to the floor which causes the mat to pick up additional debris such as dirt, dust, hair, and other detritus not to mention germs and bacteria. As a result, patrons insist that the mats are cleaned and sanitized prior to their use, for fear of becoming ill.
Gyms, workout centers, or exercise studios have classes scheduled throughout the day with minimal intermission time in order to maximize revenue. In order to provide cleaned and sanitized mats to patrons, the need for a machine that performs this function quickly becomes very important.
Many of the disclosed apparatuses teach cleaning substantially flat articles that are non-flexible. For example, U.S. Pat. No. 1,183,672, granted to Ritchey et al., discloses a machine for cleaning substantially flat articles, which includes wire bristle rollers for cleaning baking pans transferred on a conveyor. Also, U.S. Pat. No 1,930,575, granted to Wynd et al., discloses a sheet drying apparatus, which includes infeed rollers, washer spray pipes, brush rollers, outfeed rollers, and a pressurized air nozzle assembly, which are all used in conjunction for drying sheets of material, such as the glass and celluloid used in the manufacture of laminated glass.
However, there are a few apparatuses that teach cleaning flexible mats, but the apparatus only cleans one side of the mat. For instance, U.S. Pat. No. 3,396,422, granted to Haverberg, discloses a machine which washes and dries automobile floor mats. Infeed rollers are provided for feeding a floor mat to the rotary brushes. Outfeed rollers impart a squeezing action to the floor mat when fed therebetween, and a fan is provided for blowing air over the floor mat for the drying thereof. Further, U.S. Pat. No. 4,926,520, granted to Watson, describes a method and apparatus for cleaning carpet tiles. Infeed rollers are provided for continuously propelling a carpet tile over a nozzle bank that subjects the pile side of the carpet tile to a cleaning fluid spray. A scrubbing roller then scrubs the pile side of the carpet tile, and the carpet tile is next propelled over rinsing nozzles that rinse the cleaning fluid therefrom. After passing over the rinsing nozzles, the carpet tile is propelled from the cleaning compartment and to the unloading station by outfeed rollers that squeeze excess fluid from the carpet tile and also move the carpet tile over a vacuum slot, which vacuums residual fluid therefrom.
U.S. Pat. No. 5,072,478, granted to Wagner et al., teaches cleaning both sides of a semi-rigid item. Wagner describes a mobile vertical blinds cleaning machine for cleaning both surfaces of individual blinds panels of all types including plastic blinds, fabric covered blinds, and fabric blinds. It uses an elongated tank divided into separate liquid tight solution cleaning, rinse, and drying chambers, with a pair of feed rolls located at the entrance end of each of the chambers and the exit end of the drying chamber. Wagner, however, requires that the blinds be fed through a bath of solution, that the blinds be rinsed with water via nozzles, and that the blinds are blown-dry with forced air convection.
There is a machine available for sale called “The Big Squeeze Ultimate Model U-1 Floor Mat Cleaner” by J-Ko Company, which is advertised to “clean carpet and rubber floor mats” with the aid of water, chemical, and high speed nylon brushes. It is advertised for use on automobile floor mats. It uses extraction, vacuums, hot air, and rollers to dry the mats. It is very large, uses a lot of power, and requires a garden hose hook-up. The J-Ko machine would not be appropriate for use in an exercise studio or health club because of how large it is, how much power it uses, and how much water it uses.
There is another product available for sale called “Matsana”. It is advertised to “sanitize” yoga mats using ultraviolet light, only. No cleaning solution is used, however, so the machine does not clean debris from the mat.
Of the above prior art or products found for sale, none are particularly adapted for applying solution, cleaning, and removing said solution from both sides of thin, flexible mats used for yoga, pilates, barre, or other similar exercises, or for use in an gym, exercise studio, or health club. Accordingly, there is a long felt need in the art for an apparatus that cleans both sides of thin, flexible, and uncarpeted floor mats, such as those used for yoga, pilates, or barre, that does not use a lot of power, does not use a lot of water, or does not take up very much floor space.
BRIEF SUMMARY OF THE INVENTION
The present invention discloses a mat cleaning machine, and a method for cleaning the mat.
The present invention recognizes a need that the prior art does not fill. Thus, it is a general object of the present invention to provide a machine that cleans both sides of a rubberized, plastic, or foam exercise mat.
Still another object of the present invention is to provide a method for cleaning a rubberized, plastic, or foam exercise mat.
Yet another object of the present invention is to provide a mat cleaning machine that is lightweight enough so that it can be carried and moved easily in an indoor space.
Various combinations of presently disclosed features may be provided in a given embodiment thereof, in accordance with this invention. Generally, one such exemplary embodiment of the present invention includes an exercise mat cleaning machine comprising: a frame structure, infeed rollers, an infeed roller solution reservoir, secondary solution applicator rollers, a secondary solution applicator reservoir, scrubbing rollers, outfeed rollers, solution removal blades, a solution collection reservoir, mat guides, a mechanism to synchronize the rollers, and a housing.
A pair of infeed rollers is connected to the frame structure and consists of counter-rotating rollers comprised at least partially of high friction material and is particularly adapted for grabbing different types of exercise mats that a user delivers to the loading station. A pair of outfeed rollers is connected to the frame structure and consists of counter-rotating rollers that remove excess solution from the mat. Solution is applied via the infeed rollers and the secondary solution applicator rollers, also connected to the frame, and are situated in such a way as to apply solution to both sides of the mat after the mat travels through the infeed rollers and secondary rollers but before the mat reaches the scrubbing rollers. The infeed rollers and secondary rollers are at least partially bathed in solution and transport solution from the reservoirs to the mat. Scrubbing rollers are connected to the frame structure between the secondary rollers and outfeed rollers and are adapted to simultaneously scrub both sides of an exercise mat.
The present invention also includes a method of cleaning both sides of an exercise mat. The method comprises infeeding a mat with rollers into an exercise mat cleaning compartment of an exercise mat cleaning machine, applying solution to both sides of the exercise mat with solution applicator rollers in the exercise mat cleaning compartment of the exercise mat cleaning machine, both sides of the exercise mat being wetted with a cleaning solution by the solution applicator rollers. The method further includes scrubbing both sides of the exercise mat in the exercise mat cleaning compartment of the exercise mat cleaning machine with scrubbing brushes or bristles after wetting both sides of the exercise mat by the cleaning solution of the solution applicator. After scrubbing, the method includes removing the excess fluid from both sides of the exercise mat using outfeed rollers and solution removal blades in the exercise mat cleaning compartment of the exercise mat cleaning machine.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention can be better understood with reference to the following drawings. Those of skill in the art will understand that the drawings, described below, are for illustrative purposes only. The drawings are not intended to limit the scope of the present teachings in any way. The drawings disclose illustrative embodiments. They do not set forth all embodiments. Other embodiments may be used in addition or instead. Details that may be apparent or unnecessary may be omitted to save space or for more effective illustration. Conversely, some embodiments may be practiced without all of the details that are disclosed. When the same numeral appears in different drawings, it is intended to refer to the same or like components or steps.
FIG. 1 is an illustration of one embodiment of the outside of the machine.
FIG. 2 is an illustration of one embodiment of the machine to show an internal cross-section.
FIG. 3 is an illustration of one embodiment of the machine to show another internal cross-section and the route an exercise mat travels through the machine.
FIG. 4 is an illustration of one embodiment of the machine to show the mechanism used to synchronize all of the rollers.
FIG. 5 is an illustration of one embodiment of the machine to show one possible means with which to move the mat though the machine.
DETAILED DESCRIPTION OF THE INVENTION
In the following detailed description of various exemplary embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown, by way of illustration, a specific embodiments that may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present disclosure.
FIG. 1 is an illustration of one embodiment of the outside of the machine and shows the general shape and construction. FIG. 1 shows the front panel 1 of the solution collection reservoir 12 is located at the bottom of the machine. This position is beneficial because gravity channels used solution and debris removed from the mat to the solution collection reservoir 12 . The solution collection reservoir 12 can easily be removed in a drawer-like fashion to facilitate emptying the reservoir's contents.
FIG. 1 also shows the inlet of the machine, where the user inserts the mat between the counter-rotating infeed rollers 2 . The counter-rotation is helpful so the machine can continue to feed the mat into itself after the user delivers the first portion of the unclean mat to the first opening of the machine.
FIG. 1 also shows solution removal blades 3 to maximize dryness of the mat when returned to the user. In a preferred embodiment, the solution removal blades 3 may be made of a low durometer elastomer, such as silicone rubber, to conform to the various surface textures of the different styles and compositions of exercise mats.
FIG. 1 also shows slotted vents 4 to facilitate airflow through the machine.
FIG. 1 also shows an access door 5 for filling the solution reservoirs and/or unclogging a jammed mechanism, if necessary.
FIG. 2 is an illustration of one embodiment of the machine to show an internal cross-section. In a preferred embodiment, the top infeed roller 6 and bottom infeed roller 7 may be comprised of a high friction material, such as rubber, to pull the mat into the machine. The bottom infeed roller 7 may have a surface pattern or texture incorporated into the high friction material in order to scoop and transport the solution from the infeed roller solution reservoir 8 to the bottom side of the mat.
FIG. 2 also shows the top secondary solution applicator roller 9 and the bottom secondary solution applicator roller 10 . In a preferred embodiment, the bottom secondary solution applicator roller 10 may have a surface pattern or texture incorporated into the high friction material in order to scoop and transport the solution from the secondary roller solution reservoir 11 to the top side of the mat. The secondary solution applicator rollers also counter-rotate to pull the mat through the machine.
FIG. 2 also shows the scrubbing rollers 13 . In a preferred embodiment, the scrubbing rollers have bristles made of nylon or some other similar robust, flexible plastic. The bristles of the scrubbing rollers 13 may extend radially outward from the center of the roller, but then may be positioned in spiral rows that traverse the axis of the roller. As the scrubbing rollers 13 rotate about their axes, the spiral configuration of the bristles pulls debris away from the longitudinal centerline of the mat toward the outside edge of the mat.
FIG. 2 also shows the outfeed rollers 14 that are positioned closely together so as to squeeze much of the solution from the mat prior to engaging the solution removal blades 15 . As the mat passes through the solution removal blades 15 , the excess solution drains into the solution collection reservoir 12 .
FIG. 2 also shows the housing 16 that encloses the entire machine.
FIG. 3 is an illustration of one embodiment of the machine to show another internal cross-section and the route an exercise mat travels through the machine. The inlet mat guide 18 ensures that the mat travels in the proper direction to the top secondary solution applicator roller 9 . Some mats might possibly jam in the machine without the inlet mat guide 18 .
FIG. 3 also shows a mat guide 17 that redirects the mat to pass through the secondary solution applicator rollers 9 and 10 .
FIG. 3 also shows a mat guide 19 that redirects the mat to pass through the scrubbing rollers 13 .
FIG. 3 also shows a mat guide 20 that ensures the mat travels to the outfeed rollers 14 .
FIG. 4 is an illustration of one embodiment of the machine to show the mechanism used to synchronize all of the rollers. An inlet roller gear 23 , secondary roller gear 24 , scrubber roller gear 25 , and outlet roller gear 26 are synchronously linked to one another by a chain 27 . The scrubber roller gear 25 is sized differently from the other gears to increase rotational speed.
FIG. 5 is an illustration of one embodiment of the machine to show one possible means with which to move the mat though the machine. A power switch 21 can initiate an electric motor to move the mechanism that synchronously drives the gears shown in FIG. 4 and pull the mat through the machine. A hand crank 22 is provided in an alternate embodiment to operate the machine without electric power or to remove a mat from a clogged or broken down machine.
What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the described embodiments are intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. | An apparatus for cleaning rubberized, plastic, or foam exercise mats is disclosed. The apparatus includes a machine having a frame structure, at least two sets of rollers, a mechanism coupled to the rollers to push and/or pull the mat through the machine, a cleaning solution application system, a scrubbing system, a cleaning solution removal system, and a housing to enclose the machine. | 1 |
TECHNICAL FIELD
[0001] This invention pertains to an apparatus and method for separating thermoformed thin-walled articles from sheets of plastic or foam material. More particularly, this invention relates to a trim press article handling apparatus such as a web processing article registration device.
BACKGROUND OF THE INVENTION
[0002] Various devices are known for trimming thin-walled articles from sheets of thermoformed plastic material. The trimming or severing of such articles from a continuous web or sheet of thermoformable plastic and/or foam material has long been known in the art. For example, U.S. Pat. No. 4,526,074 discloses a high-speed trim press for successively trimming thermoformed articles from a continuous web of thermoformable foam or plastic material. A male locator urges the thermoformed article and web against a cutter in order to trim individual articles from the web. In the process, the articles are retained in a recess within the cutter. Subsequently trimmed articles form a state of nested articles within the recess. However, the cooperating male and female members in such trim press do not necessarily cut with sufficient accuracy, especially during high-speed trim press operations. Accordingly, improvements are needed to enhance the accuracy with which articles are aligned within a trim press such that the articles properly register with individual complementary punches and dies that cooperate to cut articles from a web.
SUMMARY OF THE INVENTION
[0003] A device is provided for registering articles, or products, during a web processing operation. More particularly, an article registering device more accurately positions web-supported articles into a trim press prior to and while severing the articles from the web. Such article registering device provides an additional degree of accuracy during such severing operation over that previously provided via adjustment and control of a web conveyor.
[0004] According to one aspect, a trim press article handling apparatus includes a punch plate, a die plate, a plunger, and a receiver. The punch plate has a punch, and the die plate has a die cooperating in relative movement with the punch plate to sever articles from a thermoformable web. The plunger is carried by one of the punch plate and the die plate having a tapered advancing head. The receiver is carried by the other of the punch plate and the die plate having a tapered recess configured to receive the plunger. A tapered article locator provided within a thermoformed web also having articles therein is captured between the plunger and the receiver as the punch plate and die plate are brought together there about, thereby imparting alignment of an article in the web between the punch and the die.
[0005] According to another aspect, a web processing article registration device includes a first support structure, a second support structure, a plunger, and a receiver. The first support structure has a punch, and the second support structure has a die configured to cooperate with the punch to sever articles from a web of thermoformable material. The plunger is carried by one of the first support structure and the second support structure, and has a tapering, leading head portion. The receiver is carried by another of the first support structure and the second support structure, and has a recess configured to receive the plunger. A tapering article locator and at least one article are provided within a web such that the tapering article locator is captured between the plunger and the receiver as the punch and the die are moved together such that the plunger interacts with the tapering article locator to align the article between the punch and the die to facilitate aligned severing of the article therebetween.
[0006] According to yet another aspect, a method is provided for aligning and severing articles from a web of thermoformable material includes: forming at least one article and a tapering recess within a web of thermoformable material; providing a trim press having a punch plate with a punch, a die plate with a die, a plunger carried by one of the punch plate and the die plate, and a receiver carried by the other of the punch plate and the die plate; receiving the formed web between the punch plate and the die plate; aligning the article between the punch and the die by moving the punch plate and the die plate so as to engage the plunger with the tapering recess such that the plunger and the receiver cooperate with the tapering recess to align the article with the punch and the die; and severing the article from the web by coacting the punch and the die while the article is aligned therebetween.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Preferred embodiments of the invention are described below with reference to the following accompanying drawings.
[0008] [0008]FIG. 1 is a vertical side view of a thermoforming machine trim press having an article registration device embodying one aspect of the invention;
[0009] [0009]FIG. 2 is a series of illustration views of a sheet of thermoformable plastic material in which articles are formed using a thermoforming machine and from which such articles are trimmed, or severed, aligned, and stacked using the apparatus of FIG. 1;
[0010] [0010]FIG. 3 is a schematic perspective view taken in an upwards direction of a top platen illustrating associated components of the article registration device configured to cooperate with the bottom platen of FIG. 4;
[0011] [0011]FIG. 4 is a schematic perspective view taken in a generally downwards direction of a bottom platen illustrating associated components of the article registration device configured to cooperate with the components on the top platen of FIG. 3;
[0012] [0012]FIG. 5 is an enlarged, simplified and schematic perspective view illustrating a thermoformed plastic web containing a plurality of thermoformed articles therein and article locator features, and further illustrating cooperation of the components for the article registration device of FIGS. 3 and 4 cooperating to align the articles with punch and die components of the trim press of FIG. 1;
[0013] [0013]FIG. 6 is a vertical sectional view taken along line 6 - 6 of FIG. 5 and showing the punch plate and die plate configured to align and sever an article from a web of material;
[0014] [0014]FIG. 7 is an enlarged and partial vertical cross-sectional view taken along line 7 - 7 of FIG. 5 illustrating a punch plate and die plate in an open position prior to aligning a web of material and articles formed therein in relation to the punch plate and die plate during a trim press operation;
[0015] [0015]FIG. 8 is an enlarged and partial vertical cross-sectional view taken along line 7 - 7 of FIG. 5 corresponding with the view of FIG. 6 showing the punch plate being lowered such that the article registration device moves the web of material into alignment such that corresponding articles are aligned between the punch plate and die plate;
[0016] [0016]FIG. 9 is an enlarged and partial vertical cross-sectional view taken along line 7 - 7 of FIG. 5 and corresponding with the views of FIGS. 7 and 8, and illustrating complete closure of the punch plate and die plate during a completed severing operation of an article, wherein the article registration device has aligned the web and articles accurately between the punch plate and die plate during a severing operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] This disclosure of the invention is submitted in furtherance of the constitutional purposes of the U.S. Patent Laws “to promote the progress of science and useful arts” (Article 1, Section 8).
[0018] Reference will now be made to a preferred embodiment of Applicant's invention. One exemplary implementation is described below and depicted with reference to the drawings comprising an article registration device and method for aligning and severing articles from a web of thermoformable material. While the invention is described by way of a preferred embodiment, it is understood that the description is not intended to limit the invention to this embodiment, but is intended to cover alternatives, equivalents, and modifications such as are included within the scope of the appended claims.
[0019] In an effort to prevent obscuring the invention at hand, only details germane to implementing the invention will be described in great detail, with presently understood peripheral details being incorporated by reference, as needed, as being presently understood in the art.
[0020] A preferred embodiment of Applicant's invention is shown on a thermoforming machine trim press that is generally designated with reference numeral 10 in FIG. 1. More particularly, an article registration device is provided on trim press 10 to more accurately align articles during severing of the articles from a web. A control system 12 choreographs operation of trim press 10 along with a conveyor 19 in order to move a web 14 of thermoformed plastic material in which individual articles, or products, 16 have earlier been formed using a thermoforming machine (not shown). In operation, web 14 is driven in intermittent motion using control system 12 to intermittently feed individual rows of articles 16 to a reasonably accurate position where the articles 16 are severed from web 14 using trim press 10 . During closure of trim press 10 , article registration device 15 more accurately position articles 16 with respect to punch and die members just prior to severing the articles 16 from web 14 .
[0021] An article accumulator 72 is also provided on trim press 10 to accumulate the severed articles 16 into individual stacks 18 , which are intermittently deposited atop a stacking conveyor 20 for delivery to a packing machine. Such stacks 18 of articles 16 are then loaded into individual packages or plastic bags.
[0022] Further details of article accumulator 72 are provided in Applicant's co-pending U.S. patent application Ser. No. ______, entitled “Article Stacking Device, Trim Press Article Accumulator, and Method of Stacking Thermoformed Articles”, naming Jere F. Irwin as inventor, and filed concurrently herewith. Such U.S. patent application Ser. No. ______, is herein incorporated by reference.
[0023] In order to improve the accuracy with which articles 16 are severed from a web by trim press 10 , article registration device 15 is provided on trim press 10 having desired features of Applicant's invention. Article registration device 15 provides highly accurate article registration between punch plate 28 and die plate 30 to ensure that articles 16 are accurately severed from web 14 . Accordingly, articles 16 are severed in a highly uniform and centered manner from web 14 such that a uniform flange is provided about such articles when articles 16 , for example, comprise plastic plates.
[0024] In the absence of Applicant's article registration device 15 , article registration is carried out solely by adjusting the positioning of a web conveyor 19 , as shown and described below in simplified form. Additionally, a coarse level of article registration is carried out by adjusting the operation of controller 40 in order to adjust the advancement and positioning of individual articles between punch plate 28 and die plate 30 .
[0025] However, it is oftentimes very difficult to adjust the set-up and component positioning for a web conveyor in order to accurately and precisely deliver articles 16 between punch plate 28 and die plate 30 . Hence, article registration implemented solely using conveyor set-up and control does not sever such articles in a sufficiently uniform and accurate manner. Furthermore, there are limitations to the accuracy with which a servo motor can drive web conveyor 19 , and therefore, in the ability of such servo motors to accurately place articles 16 between punch plate 28 and die plate 30 . Oftentimes, it is the case that articles 16 are off by several millimeters, which can produce an undesirable effect, particularly where article 16 is of a complicated shape, or article 16 comprises a foldable container having a hinge which requires a high degree of accuracy in forming and severing thereof.
[0026] Accordingly, article registration device 15 , as described below with reference to FIGS. 3 - 9 , provides an enhanced ability to accurately register articles 16 between punch plate 28 and die plate 30 when severing such articles 16 therebetween.
[0027] As shown in FIG. 1, web conveyor 19 is illustrated in simplified form as a drive wheel assembly 21 including a servo motor (not shown) that is controllably actuated via control system 12 to impart intermittent motion to web 14 . As shown in FIG. 1, drive wheel assembly 21 comprises two pairs of co-acting top and bottom wheels that are provided along opposite side edges of web 14 . A topmost wheel of each pair comprises a drive wheel and a bottom-most wheel of each pair comprises a follower wheel that is actuated and driven by a servo motor. Accordingly, actuation of drive wheel assembly 21 via controller 40 is operative to intermittently deliver rows of articles 16 into trim press 10 . Such rows of articles 16 are then severed as control system 12 actuates a severing operation via trim press 10 . Subsequently, a scrap web 22 is delivered from trim press 10 and ground into small pieces using a comminuting device configured for grinding up scrap web 22 , as described below in reference to FIG. 2.
[0028] As shown in FIG. 1, drive wheel assembly 21 comprises a dual servo motor driven roller feed assembly. However, it is understood that drive wheel assembly 21 represents a simplified version of a web conveyor for delivering thin web materials into trim press 10 . One exemplary detailed construction for a web conveyor is disclosed in U.S. Pat. No. 5,806,745, herein incorporated by reference.
[0029] Several different comminuting apparatus suitable for grinding up scrap web 22 are disclosed in U.S. Pat. Nos. 4,687,144; 5,836,527; 5,860,607; and 5,893,523, each herein incorporated by reference. Scrap web 22 is accordingly forwarded into such a recycling, pulverizing machine where web 22 is shredded and then later recycled to form a new web of thermoformable plastic material.
[0030] Details of one exemplary thermoforming machine suitable for forming articles 16 within web 14 are disclosed in U.S. Pat. No. 5,773,540. U.S. Pat. No. 5,773,540 is herein incorporated by reference.
[0031] Trim press 10 includes a movable upper platen 24 , a stationary lower platen 26 , a punch plate 28 , and a die plate 30 . Punch plate 28 is carried for movement by movable upper platen 24 , whereas die plate 30 is fixedly carried by stationary lower platen 26 . However, it is understood that platen 26 and die plate 30 can also be movably supported for operation according to an alternative construction.
[0032] As shown in FIG. 1, upper platen 24 is carried for vertical reciprocation by crank arm assemblies 32 - 35 . Details of one exemplary thermoforming machine suitable for incorporating accumulator 72 and having such crank arm assembly are shown in U.S. patent application Ser. No. 08/691,856, now U.S. Pat. No. ______, entitled “Machine Trim Press Having Counterbalance Features”, and naming the inventor as Jere F. Irwin. Such U.S. patent application Ser. No. 08/691,856 is herein incorporated by reference.
[0033] Each crank arm assembly 32 - 35 comprises a throw arm 36 and a platen connecting rod 38 , wherein arm 36 and rod 38 cooperate to form a kinematic linkage that drives a dedicated corner of platen 24 for vertical, guided reciprocation. Additionally, two cylindrical, stationary guide posts (not shown) are rigidly carried by a frame 11 to support platen 24 for movement in an axial, vertical direction. Optionally, only four guide posts can be configured to support platen 24 with two corresponding bushings.
[0034] Even furthermore, four additional, stationary guide posts 60 - 63 (see FIG. 3) are rigidly supported or press fit within apertures 64 - 66 of die plate 30 to further guide sliding movement of punch plate 28 there along. Bushings 164 - 167 (of FIG. 3) in punch plate 28 slide over guide posts 60 - 63 . Such platen guide posts (not shown) are understood in the art and have been omitted from the figures in order to simplify the drawing and to prevent obscuring the invention at hand. Furthermore, punch plate/die plate guide posts 60 - 63 have been eliminated from FIG. 1 to also prevent obscuring the invention at hand.
[0035] Control system 12 of FIG. 1 includes a controller 40 having processing circuitry 42 and memory 44 . According to one construction, processing circuitry 42 is provided by a central processing unit (CPU). According to another construction, processing circuitry 42 is provided by a microcontroller which cooperates to form controller 40 . It is understood that memory 44 is operative to store software subroutines that are retrieved and implemented on processing circuitry 42 in order to impart motion control functionality by way of controller 42 to trim press 10 .
[0036] As shown in FIG. 1, control system 12 is operative to generate control signals that direct operation of a servo drive motor 46 that drives crank arm assemblies 32 - 35 and thereby imparts reciprocation to upper platen 24 . Servo drive motor 46 comprises a highly accurate computerized servo motor and servo drive which can be accurately driven by control system 12 . In operation, servo drive motor 46 drives a gear box 48 that imparts a rotary motion to each of crank arm assemblies 3235 . Furthermore, control system 12 is operative to deliver a control signal to a servo drive motor 50 that advances article conveyor 20 . Additionally, control system 12 delivers another control signal to a plurality of linear actuators 52 that raise and lower article conveyor 20 as well as stacks 18 of severed articles 16 during stacking, packaging and/or bagging operations. One suitable linear actuator 52 comprises a plurality of ball screw actuators having electric drive motors. Alternatively, linear actuator 52 comprises a plurality of pneumatic or hydraulic actuators, or pistons, configured to raise and lower article conveyor 20 relative to lower platen 26 .
[0037] [0037]FIG. 2 illustrates in simplified schematic form the processing of a thermoformable plastic web 14 wherein web 14 is initially heated in an oven after which individual articles 16 are formed in the heated web using a thermoforming machine. Subsequently, rows 54 of articles 16 are successively severed from web 14 and stacked using a trim press 10 (of FIG. 1) having the novel features of Applicant's invention. Pairs of article locators 87 and 89 in web 14 facilitate accurate severing of articles 16 from web 14 . Accumulator 72 then stacks successive rows 54 beneath web 14 , after which an array 58 of stacks 18 of articles 16 is retrieved from beneath web 14 by activating conveyor 20 (of FIG. 1). Scrap web 22 is progressively advanced forward into a comminuting apparatus as described above, which generates subdivided pieces 56 of a sufficiently small desired size.
[0038] As shown in FIG. 3, punch plate 28 coacts with die plate 30 of FIGS. 4 - 9 when severing and accumulating articles. Punch plate 28 includes bronze bushings 164 - 167 that are fitted in slidable engagement over guide posts 60 - 63 , respectively. Accordingly, punch plate 28 is movably supported along guide posts 60 - 63 , and is further driven by crank arm assemblies 32 - 35 via servo drive motor 46 and gearbox 48 (of FIG. 1). As shown in FIG. 3, a plurality of punches, or male die members, 96 are provided on a bottom surface of punch plate 28 . Punches 96 are individually arranged so as to coact with die member 94 of lower platen 26 (of FIG. 4). Accordingly, such coaction between cutting edges 68 and 98 severs articles from a web in an accurate manner as plungers 100 and 102 cooperate with article registration cavities 90 and 92 to center article locators 87 and 89 within web 14 (see FIG. 2), which causes articles 16 in web 14 to also be accurately aligned between punches 96 (see FIG. 3) and corresponding dies present within die member 94 (see FIG. 4). Accordingly, coaction between corresponding cutting edges 98 on each punch 96 (of FIG. 3) and complementary cutting edges 68 of die member 94 (of FIG. 4), in combination with article alignment between plungers 100 and 102 and article locators 87 and 89 , ensures accurate severing of articles from a web. Following such severing, such articles are stacked by way of accumulator 72 (see FIG. 1).
[0039] Accordingly, article registration plungers 100 and 102 cooperate with substantially complementary article registration cavities 90 and 92 (of FIG. 4) in order to laterally align a web and corresponding web-formed articles accurately between punch plate 28 (of FIG. 3) and die plate 30 (of FIG. 4). It is understood that such lateral alignment occurs in two dimensions as article locators 87 and 89 taper with depth so as to form a frustoconical or funnel-shaped cavity which imparts alignment to articles 16 (see FIG. 5) in a two-dimensional plane corresponding with the plane of web 14 .
[0040] As shown in FIG. 5, article registration plunger 100 (as well as plunger 102 ) cooperates with substantially complementary article registration cavity 92 (as well as cavity 90 ) in order to align web 14 and articles 16 between die plate 30 and punch plate 28 (of FIG. 3). As shown in FIG. 5, it is understood that plunger 102 is carried for vertical reciprocation by punch plate 28 (of FIG. 3).
[0041] [0041]FIG. 6 illustrates an alignment and severing operation as carried out between punch plate 28 and die plate 30 when severing individual articles 16 from web 14 by coaction of cutting edges 68 and 98 . More particularly, downward movement of plungers 100 and 102 causes aligned registration of tapered article locators 87 and 89 in all directions lying in the plane of web 14 . More particularly, plungers 100 and 102 are lowered in a downward axial direction, causing centering of tapered article locators 87 and 89 there about, which also pulls web 14 and articles 16 into aligned registration there about. Such aligned registration of web 14 , and cavities 90 and 92 between plungers 100 and 102 , and locators 87 and 89 , also imparts precise and accurate alignment of articles 16 between cutting edge 98 of punch 96 and cutting edge 68 of individual dies in die member 94 . Accordingly, improvements are imparted by increasing the accuracy with which individual articles are severed between punch plate 28 and die plate 30 . As shown in FIG. 6, severed articles 16 are released through coaction of gravity through article cavity 70 where they are accumulated there below on an article conveyor (not shown).
[0042] [0042]FIG. 7 illustrates the assembly of article plunger 102 on a bottom surface of punch plate 28 , and the construction of article registration cavity 92 above die plate 30 . As shown in FIG. 7, web 14 has been advanced between punch plate 28 and die plate 30 wherein a formed article (not shown) is about to be severed between punch plate 28 and die plate 30 . Misalignment is present between such article (not shown) and the associated cutting surfaces of punch plate 28 and die plate 30 , as indicated by the misalignment of tapered article locator 87 in relation to article registration cavity 92 . It is understood that the positional relationship between an article formed in web 14 and tapered article cavities 87 and 89 corresponds precisely with the positional location of cutting surfaces in punch plate 28 and die plate 30 relative to article registration cavities 90 and 92 .
[0043] Likewise, plungers 100 and 102 are supported positionally in punch plate 28 in relation to the position of tapered article locators 87 and 89 when articles (not shown) in web 14 are accurately aligned with such cutting edges. Hence, plunger 102 is axially, downwardly displaced such that plunger 102 engages with misaligned tapered article locator 87 , causing lateral alignment of locator 87 along with web 14 and any articles formed therein, as illustrated below with reference to FIGS. 8 and 9.
[0044] As shown in FIG. 7, plunger 102 (as well as plunger 100 ) is constructed with an aluminum central retainer 85 having an outwardly biased shoulder 104 , a threaded aperture 99 , and a hemispherical end portion 93 . An ultra-high molecular weight (UHMW) polyethylene, or plastic, outer sleeve 88 is entrapped by central retainer 85 onto punch plate 28 . More particularly, a coil steel spring 91 downwardly biases outer sleeve 88 until an inwardly extending shoulder 106 on outer sleeve 88 engages with shoulder 104 of central retainer 85 .
[0045] In assembly, a threaded fastener 86 is received within a fastener aperture 97 of punch plate 28 so as to retain and assemble plunger 102 onto a bottom surface of plunger plate 28 . Spring 91 is compressively biased between a bottom surface of punch plate 28 and a hemispherical circumferential sleeve shoulder 95 of outer sleeve 88 . Accordingly, outer sleeve 88 is downwardly biased from punch plate 28 , until coaction of plunger 102 causes upward biasing of outer sleeve 88 through coaction with tapered article locator 87 and article registration cavity 92 , as shown in FIGS. 8 and 9.
[0046] As further shown in FIG. 7, article registration cavity 92 (as well as cavity 90 ) comprises a frustoconical aperture 82 and a cylindrical aperture 84 . According to one construction, hemispherical circumferential sleeve shoulder 95 tapers inwardly in a radial direction such that downward biasing of plunger 102 into tapered, or tapering, article locator 87 will impart alignment of web 14 and associated articles with respect to frustoconical aperture 82 . However, it is understood that frustoconical aperture 82 and hemispherical circumferential sleeve shoulder 95 can have different tapered shapes as long as such tapering imparts alignment as plunger 102 is downwardly biased into tapered article locator 87 and frustoconical aperture 82 . Likewise, article locator 87 can optionally have a modified shape, and perhaps even a cylindrical shape if such shape coacts with plunger 102 to cause alignment of articles. Further optionally, plunger 102 can have a relatively square, or flat, head as long as tapering article locator 87 coacts with such head so as to impart alignment of a web and articles therein in response to coaction therebetween.
[0047] In further alternative constructions, it is understood that article registration cavity 92 can comprise a single cylindrical aperture, or other variously shaped, oversize aperture. However, the provision of frustoconical aperture 82 further ensures the accurate alignment of articles in web 14 in relation to cutting surfaces on punch plate 28 and die plate 30 .
[0048] [0048]FIG. 8 illustrates the lowering of punch plate 28 during an article severing operation of a trim press. In such case, plunger 102 initiates engagement with tapered article locator 87 , causing lateral alignment of web 14 (and associated articles therein) relative to punch plate 28 and die plate 30 . As shown in FIG. 8, plunger 102 initiates contact such that plunger 102 is compressively biased in an upward axial direction as punch plate 28 is lowered further into contact with die plate 30 and finally into complete compression, as illustrated in FIG. 9. Such coaction causes lateral movement of web 14 , which causes corresponding article alignment between punch plate 28 and die plate 30 .
[0049] [0049]FIG. 9 illustrates a completely closed stage between punch plate 28 and die plate 30 wherein plunger 102 is completely compressed, and web 14 is accurately aligned therebetween. As shown in FIG. 9, tapered article locator 87 is accurately positioned within article registration cavity 92 , which also coincides with accurate registration of articles between cutting edges of punch plate 28 and die plate 30 .
[0050] In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents. | A trim press article handling apparatus includes a punch plate, a die plate, a plunger, and a receiver. The punch plate has a punch, and the die plate has a die cooperating in relative movement with the punch plate to sever articles from a thermoformable web. The plunger is carried by one of the punch plate and the die plate having a tapered advancing head. The receiver is carried by the other of the punch plate and the die plate having a tapered recess configured to receive the plunger. A tapered article locator provided within a thermoformed web also having articles therein is captured between the plunger and the receiver as the punch plate and die plate are brought together there about, thereby imparting alignment of an article in the web between the punch and the die. A method for aligning and severing articles from a web is also provided. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application 61/519,556, entitled “ADJUSTABLE BRACKED FOR THE ATTACHMENT OF BUILDING CLADDING SYSTEMS” filed on May 25, 2011, which is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to devices used in the construction industry to fasten cladding systems to buildings.
BACKGROUND OF THE INVENTION
[0003] Recent changes in the International Energy Code require “continuous insulation” in many exterior wall assemblies. These requirements were added in an effort to reduce the amount of thermal bridging that occurs in many assemblies due to these assemblies containing conductive materials that extend from the warm side of the wall to the cold side of the wall. In many assemblies, thermal bridging can reduce the effectiveness of the insulation in the assembly by up to 50% and more depending on the frequency of the bridging.
[0004] The present state of the art for attaching many cladding systems to buildings is via the use of what is commonly called “Z-furring” or similar metal devices. These devices are installed in a continuous manner usually in horizontal or vertical orientations and at predetermined spacings. Insulation is then installed between the devices resulting in the devices bridging through the insulation from the warm side of the insulation to the cold side of the insulation in a continuous manner thus reducing the effectiveness of the insulation.
[0005] In using the present state of the art devices, adjustability to compensate for construction tolerances, out of plumb framing and out of plane substrates is achieved via the use of shims installed between the device and the substrate. Also the devices provide a means of retaining the insulation installed between the devices in place. This is usually achieved via a retaining element or a friction fit.
[0006] The principal objective of the present invention is to provide a new and novel means of fastening cladding systems to buildings in a way that substantially reduces thermal bridging. Another objective of the present invention is to provide adjustability of the fastening system within the device. Another objective of the present invention is to provide a mean of mechanically fastening rigid and semi-rigid insulation in the exterior wall assembly.
SUMMARY OF THE INVENTION
[0007] Aspects and embodiments of the present invention are directed to providing a new and novel device for securely fastening cladding systems to back up walls of buildings in a way that substantially reduces thermal bridging. Another aspect of the present invention is to provide adjustability of the plane for fastening of the cladding systems to back up walls of buildings with the device of the present invention. Still another aspect is to provide for securing rigid and semi-rigid insulation to the back up wall with the device of the present invention. A further aspect of the present invention is to provide for varying thickness insulation layers to be secured to the back up wall of buildings with the device of the present invention. Various embodiments and aspects of an adjustable bracket used for the attachment of building cladding systems or panels to building back up walls that substantially minimizes thermal bridging, provide adjustability of the plane for connection such cladding systems, and that provides for securing varying thickness rigid and semi-rigid insulation to the back up wall of the building enclosure assembly are disclosed herein.
[0008] In one embodiment, the device comprises a flat base plate that is attached to a first end of a post. This post is inwardly threaded at a second end that is not attached to the base plate. An outwardly threaded post is engaged to the inwardly threaded post at a first end of the outwardly threaded post by the threading of the first end of the outwardly threaded post into the second end of the inwardly threaded post. An additional flat plate is attached to a second end of the outwardly threaded post that is not threaded into the inwardly threaded post.
[0009] One embodiment of a device for use in the fastening of a panel or cladding to a back up wall comprises a base plate constructed and arranged to be affixed to the wall, a panel connecting plate constructed and arranged to provide attachment points for fastening of the panel or cladding to the panel connecting plate, and a connecting assembly that connects the panel connecting plate to the base plate and that is constructed and arranged so as to provide minimal thermal bridging between the base plate and the panel connecting plate through an insulation layer that covers the base plate and the wall, while simultaneously providing structural integrity for attaching the panel or cladding to the wall.
[0010] One aspect of this embodiment of the device is that the connecting assembly is constructed and arranged to be adjustable in length so as to provide for different first lengths between the base plate and the panel connecting plate so as to compensate for variations in a planar location of the wall.
[0011] Another aspect of this embodiment of the device is that the connecting assembly can comprise a threaded post connected to the base plate and having a threaded aperture along at least a portion of the threaded post, and a threaded post connected to the panel connecting plate having an threaded outside diameter along at least of a portion of the threaded post that is constructed and arranged to mate with threaded post to provide the adjustable first length. Another aspect of this embodiment of the device is the device can also comprise an insulation retaining plate having a threaded aperture constructed and arranged to mate with the threaded post so as to be disposed between the base plate and the panel connecting plate and constructed and arranged to have its position with respect to the base plate be adjustable so as to provide for a varying second distance between the base plate and the insulation retaining plate to secure the insulation layer between the base plate and the insulation retaining plate.
[0012] Another aspect of this embodiment of the device is that the connecting assembly can comprise an insulation retaining plate to be disposed between the base plate and the panel connecting plate and constructed and arranged to have its position with respect to the base plate be adjustable so as to provide for a varying distance between the base plate and the insulation retaining plate so as to secure the insulation layer between the base plate and the insulation retaining plate.
[0013] Another embodiment of a device for use in the fastening of a panel or cladding to a back up wall comprises a base plate constructed and arranged to be affixed to the wall, a panel connecting plate constructed and arranged to provide attachment points for fastening of the panel or cladding to the panel connecting plate, a connecting assembly that connects the panel connecting plate to the base plate so as to provide structural integrity for attaching the panel or cladding to the wall, and an insulation retaining plate constructed and arranged to be disposed between the base plate and the panel connecting plate and constructed and arranged to have its position with respect to the base plate be adjustable so as to provide for a varying second distance between the base plate and the insulation retaining plate so as to secure an insulation layer between the base plate and the insulation retaining plate.
[0014] One aspect of this embodiment of the device is that the connecting assembly is constructed and arranged to be adjustable in length so as to provide for different first lengths between the base plate and the panel connecting plate so as to compensate for variations in a planar location of the wall.
[0015] Another aspect of this embodiment of the device is that the connecting assembly includes a threaded post connected to the base plate and having a threaded aperture along at least a portion of the threaded post, and a threaded post connected to the panel connecting plate having an threaded outside diameter along at least of a portion of the threaded post that is constructed and arranged to mate with threaded post to provide the adjustable first length. Another aspect of this embodiment of the device is that the insulation retaining plate has a threaded aperture constructed and arranged to mate with the threaded post.
[0016] Another aspect of this embodiment of the device is that the connecting assembly is constructed and arranged so as to provide minimal thermal bridging between the base plate and the panel connecting plate through the insulation layer.
[0017] Another embodiment of a device for use in the fastening of a panel or cladding to a back up wall comprises a base plate constructed and arranged to be affixed to the wall, a panel connecting plate constructed and arranged to provide attachment points for fastening of the panel or cladding to the panel connecting plate, and an adjustable length connecting assembly that connects the panel connecting plate to the base plate and that is constructed and arranged to be adjustable in length so as to adjust a position of the panel connecting plate with respect to the base plate so as to provide for different first lengths between the base plate and the panel connecting plate, the adjustable length connecting assembly further constructed and arranged so as to provide minimal thermal bridging between the base plate and the panel connecting plate through an insulation layer that covers the base plate and the wall, while simultaneously providing structural integrity for attaching the panel or cladding to the wall.
[0018] One aspect of this embodiment of the device is that the adjustable length connecting assembly includes a threaded post connected to the base plate and having a threaded aperture along at least a portion of the threaded post; and a threaded post connected to the panel connecting plate having an threaded outside diameter along at least of a portion of the threaded post that is constructed and arranged to mate with threaded post to provide the adjustable first length. Another aspect of this embodiment of the device is that the device can further comprise an insulation retaining plate having a threaded aperture constructed and arranged to mate with the threaded post so as to be to be disposed between the base plate and the panel connecting plate and constructed and arranged to have its position with respect to the base plate be adjustable so as to provide for a varying second distance between the base plate and the insulation retaining plate to secure the insulation layer between the base plate and the insulation retaining plate.
[0019] Another aspect of this embodiment of the device is that the device can further comprising an insulation retaining plate constructed and arranged to be disposed between the base plate and the panel connecting plate and constructed and arranged to have its position with respect to the base plate be adjustable so as to provide a varying second distance between the base plate and the insulation retaining plate so as to secure the insulation layer between the base plate and the insulation retaining plate.
[0020] Another embodiment of a device for use in the fastening of a panel or cladding to a back up wall comprises a base plate constructed and arranged to be affixed to the wall, a panel connecting plate constructed and arranged to provide attachment points for fastening of the panel or cladding to the panel connecting plate, an adjustable length connecting assembly that connects the panel connecting plate to the base plate and that is constructed and arranged to be adjustable in a length so as to adjust a position of the panel connecting plate with respect to the base plate so as to provide for a varying first distance between the base plate and the panel connecting plate, and an insulation retaining plate constructed and arranged to be disposed between the base plate and the panel connecting plate and constructed and arranged to have its position be adjustable with respect to the base plate so as to provide for a varying second distance between the base plate and the insulation retaining plate for securing an insulation to the wall.
[0021] One aspect of this embodiment of the device is that the adjustable length connecting assembly includes a threaded post connected to the base plate and having a threaded aperture along at least a portion of the threaded post, and a threaded post connected to the panel connecting plate having an threaded outside diameter along at least of a portion of the threaded post that is constructed and arranged to mate with threaded post to provide the adjustable first length.
[0022] Another aspect of this embodiment of the device is that the connecting assembly is constructed and arranged so as to provide minimal thermal bridging between the base plate and the panel connecting plate through the insulation layer.
[0023] Another aspect of the various embodiments of the device is that the connecting assembly is constructed and arranged to transfer any loads imposed by wind and seismic forces from the panel or cladding to the back up wall.
[0024] Another aspect of the various embodiments of the device is that the base plate comprises a metal. Another aspect of this embodiment of the device is that the panel connecting plate comprises a metal. Another aspect of this embodiment of the device is that the insulation retaining plate comprises a metal.
[0025] Another aspect of the various embodiments of the device is that the base plate is constructed and arranged with apertures that are constructed and arranged for fasteners to be inserted through the apertures to fasten the base plate to the wall. An alternative aspect of this embodiment of the device is that the base plate is constructed and arranged of materials and a thickness so that it can be welded to the wall.
[0026] Another aspect of the various embodiments of the device is that the panel connecting plate can be constructed and arranged so that fasteners can be used to connect the panel or cladding or their fastening assemblies to the panel connecting plate. According to one embodiment, the fasteners can be metal.
[0027] Another aspect of the various embodiments of the device is that the device can further be provided with attachment components that are constructed and arranged to be connected to the panel connecting plate. The attachment components can comprise metal or other materials.
[0028] In another embodiment, the device comprises a flat base plate that is attached to a first end of a post. This post is inwardly threaded at a second end that is not attached to the base plate. A first end of an outwardly threaded post is engaged to the second end of the inwardly threaded post-type structure by the threading of the outwardly threaded post into the inwardly threaded post. A flat plate is attached to a second end of the outwardly threaded post that is not threaded into the inwardly threaded post. This embodiment also comprises a substantially flat plate that contains a threaded aperture through its middle and that is threaded onto the outwardly threaded post. This plate may or may not have profiles protruding form each face to both secure the plate to both rigid and semi-rigid insulation and to provide structure to rotate the plate in order to thread it up or down on the outwardly threaded post.
[0029] One embodiment of a method of affixing a panel or a cladding to a back-up wall, comprises fastening a plurality of base plates to the wall, connecting a panel connecting plate to each of the base plates with a connecting assembly, adjusting a position of the panel connecting plate relative to the base plate with the connecting assembly to provide a desired first distance between the panel connecting plate and the base plate, affixing attachment components to the plurality of panel connection plates, and fastening a panel or cladding to the fastening components.
[0030] One aspect of this embodiment of the method is that the method can further comprise adding an insulation layer to the wall after fastening the plurality of base plates to the wall so that the insulation layer covers the plurality of base plates and the wall.
[0031] Another aspect of this embodiment of the method is that the method can further comprise securing the insulation layer to the base plate and the wall with an insulation retaining plate connected between the base plate and the panel connecting plate, by positioning the insulation retaining plate a second distance away from the base plate so as to hold the insulation layer in place.
[0032] Another aspect of this embodiment of the method is that the method can further comprise affixing continuous attachment components to the panel connection plate with fasteners, affixing clips to the continuous attachment components, and mating the clips affixed to the continuous attachment component to the stiffener plates attached to the panel or cladding.
[0033] One aspect of this embodiment of the method is that the plurality of base plates can be attached to the wall by affixing each base plate to the wall with a plurality of fasteners. Another aspect of this embodiment of the method is that the plurality of base plates can be attached to the wall by welding each base plate to the wall.
[0034] One aspect of this embodiment of the method is that the panel or cladding can be attached to the plurality of panel connection plates of the plurality of devices of the present invention with a plurality of fasteners. Alternatively the panel or cladding can be attached to the plurality of panel connection plates of the plurality of devices of the present invention by welding the panel or cladding to each panel connection plate.
[0035] Still other aspects, embodiments, and advantages of these exemplary aspects and embodiments, are discussed in detail below. Embodiments disclosed herein may be combined with other embodiments in any manner consistent with at least one of the principles disclosed herein, and references to “an embodiment,” “some embodiments,” “an alternate embodiment,” “various embodiments,” “one embodiment” or the like are not necessarily mutually exclusive and are intended to indicate that a particular feature, structure, or characteristic described may be included in at least one embodiment. The appearances of such terms herein are not necessarily all referring to the same embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] Various aspects of at least one embodiment are discussed below with reference to the accompanying figures, which are not intended to be drawn to scale. The figures are included to provide illustration and a further understanding of the various aspects and embodiments, and are incorporated in and constitute a part of this specification, but are not intended as a definition of the limits of the invention. In the figures, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every figure. The following description of the invention will be better understood with reference to the accompany Figures in which:
[0037] FIG. 1 is a perspective view of one embodiment of the device of the present invention;
[0038] FIG. 2 is a sectional view of one embodiment of the device of the present invention illustrated as operatively engaged in a building enclosure assembly and fastening a composite metal panel veneer to the building at one fastening point, and further illustrating a flat metal strap is used to fasten the composite metal panel veneer to device of the present invention;
[0039] FIG. 3 is a perspective view of one embodiment of the device of the present invention illustrated as operatively engaged in the building enclosure assembly fastening a composite metal panel veneer to the building at one fastening point, and further illustrating a flat metal strap is used as an attachment component to fasten the composite metal panel veneer to device of the present invention;
[0040] FIG. 4 is a sectional view of one embodiment of the device the present invention illustrated as operatively engaged in the building enclosure assembly fastening a composite metal panel veneer to the building at one fastening point, and further illustrating a metal “Z-furring” is used as an attachment component to fasten the composite metal panel veneer to device of the present invention; and
[0041] FIG. 5 is a sectional view of one embodiment of the device the present invention illustrated as operatively engaged in the building enclosure assembly fastening a composite metal panel veneer to the building at one fastening point, and further illustrating a metal hat furring is used as an attachment component to fasten the composite metal panel veneer to device of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] This invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” “having,” “containing,” “involving,” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
[0043] Various aspects of at least one embodiment are discussed below with reference to the accompanying figures, which are not intended to be drawn to scale. The figures are included to provide illustration and a further understanding of the various aspects and embodiments, and are incorporated in and constitute a part of this specification, but are not intended as a definition of the limits of the invention. In the figures, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every figure.
[0044] According to aspects of this disclosure, various devices and methods are provided herein for securely fastening cladding systems or panels to back up walls of buildings in a way that substantially reduces thermal bridging. In addition, various devices and methods are provided herein for providing adjustability of a plane of a plate or other type structure for fastening of the cladding systems or panels to such back up walls of buildings. Further, various devices and methods are provided herein for securing varying thickness insulation layers, such as rigid and semi-rigid insulation layers, to the back up wall.
[0045] By way of introduction and referring to the Figures, Referring to FIG. 1 , there is illustrated one embodiment of a device 10 that comprises a flat base plate 20 , an inwardly threaded post 30 , an outwardly threaded post 40 and a flat panel connecting plate 50 . The present invention may or may not also have a flat insulation retaining plate 60 with a threaded aperture that threads onto the outwardly threaded post 40 . The base plate 20 has two apertures 21 in it that facilitate the fastening of the base plate 20 to a substrate such as a back up wall with fasteners 23 . To the base plate 20 is attached the inwardly threaded post 30 at one end 31 of the inwardly threaded post 30 . The other end 32 of the inwardly threaded post 30 receives one end of the outwardly threaded post 40 . This connection through the engagement of the threads of the inwardly threaded post 30 and the outwardly threaded post 40 allows for adjustability of the overall length of the device of present invention 10 . To the other end of the outwardly threaded post 40 is attached a flat plate 50 . Optionally, the flat insulation retaining plate 60 is engaged with the outwardly threaded post 40 via a round threaded aperture 61 that is located substantially in the center of the flat insulation retaining plate 60 .
[0046] FIGS. 2 and 3 are sectional and perspective views, respectively, illustrating an embodiment of the device 10 of the invention as intended to be utilized at one fastening point in a building enclosure assembly for fastening a composite metal panel veneer to the building. FIGS. 2 and 3 further illustrate that the base plate 20 is fastened to the back-up wall assembly 70 that, in the illustrated example consists of light gage metal framing 71 and gypsum sheathing 72 , via the use of fasteners 23 which are installed through the apertures 21 in the base plate 20 and engaged with the back-up wall 70 . In other applications, the back-up wall may consist of wood framing and wood sheathing, concrete masonry units or concrete and that the device of the present invention can be used to securely attach panels or cladding systems to any of such back-up walls. In any of these applications, there may or may not exist water resistant barrier 73 that may serve the function of being an air and vapor barrier for the exterior wall assembly. It is to be appreciated that a plurality of the base plates 20 of the device 10 of the present invention will be installed on the back-up wall assembly 70 . The base plates may be, but need not be, installed in a predetermined pattern to the back up wall assembly. After the base plates 20 are installed, an insulation layer 80 is then installed. If the insulation layer 80 is comprised of unitized unit of insulation, the optional flat insulation retaining plate 60 is then threaded onto the threaded post 40 through the aperture 61 in the flat insulation retaining plate 60 . If the insulation layer 80 is comprised of, for example a spray polyurethane foam, then the optional flat insulation retaining plate 60 is not needed in the assembly. The outwardly threaded post 40 is then installed into the inwardly threaded post 30 by twisting the threads of each component together similar to how a screw threads into a bolt. The flat panel connecting plate 50 is twisted thus threading the outwardly threaded post 40 into the inwardly threaded post 30 until the face of the flat panel connecting plate 50 is substantially in the desired plane for the attachment of the veneer assembly 90 to the panel connecting plate 50 of the device of the present invention. The flat insulation retaining plate 60 is then threaded down the outwardly threaded post 40 by rotating the flat insulation retaining plate 60 so that the threaded aperture 61 of the flat insulation retaining plate 60 threads down the outwardly threaded post 40 until it comes into contact with the insulation layer 80 thus securing the insulation layer 80 in place via a compression fit. As illustrated in FIGS. 2 and 3 , according to aspects of the device, a flat metal strap 92 is used as an attachment component to fasten the composite metal panel veneer system 91 to the panel connecting plate 50 of the device of the present invention.
[0047] One embodiment of the veneer assembly 90 as shown in FIGS. 2 and 3 includes a flat metal plate 92 as a connecting component which is fastened either horizontally or vertically to consecutive flat panel connecting plates 50 of the present invention 10 via the use of fasteners 93 which engage both the flat metal plate 92 and the flat panel connecting plate 50 of the device 10 of the present invention. To this flat steel plate 92 may or may not be attached intermittent metal clips 94 which are fastened to the flat metal plate 92 at prescribed spacings via the use of fasteners 95 which engage both the flat metal plate 92 and the intermittent metal clip 94 . The veneer assembly may or may not also contain panel stiffener plates 96 that engage with the intermittent clips 94 due to the mating configurations of the two elements. These stiffener plates 96 are mechanically fastened to the metal veneer panels 91 via fasteners 97 at prescribed intervals. The veneer assembly 90 may or may not also contain a strip of metal panel veneer 98 located vertically and/or horizontally between the metal veneer panels 91 .
[0048] Another embodiment of the veneer assembly 90 as shown in FIG. 4 includes “Z-furring” 100 as a connecting component which is fastened either horizontally or vertically to consecutive flat panel connecting plates 50 of the present invention 10 via the use of fasteners 93 which engage both the “Z-furring” 100 and the flat panel connecting plate 50 of the device 10 of the present invention. To this “Z-furring” may or may not be attached intermittent metal clips 94 which are fastened to the “Z-furring” 100 at prescribed spacings via the use of fasteners 95 which engage both the “Z-furring” 100 and the intermittent metal clip 94 . The veneer assembly may or may not also contain panel stiffener plates 96 that engage with the intermittent clips 94 due to the mating configurations of the two elements. These stiffener plates 96 are mechanically fastened to the metal veneer panels 91 via fasteners 97 at prescribed intervals. The veneer assembly 90 may or may not also contain a strip of metal panel veneer 98 located vertically and/or horizontally between the metal veneer panels 91 .
[0049] Another embodiment of the veneer assembly 90 as shown in FIG. 5 includes hat furring 101 as a connecting component which is fastened either horizontally or vertically to consecutive flat panel connecting plates 50 of the present invention 10 via the use of fasteners 93 which engage both the hat furring 101 and the flat panel connecting plate 50 of the device 10 of the present invention. To this hat furring 101 may or may not be attached intermittent metal clips 94 which are fastened to the hat furring 101 at prescribed spacings via the use of fasteners 95 which engage both the hat furring 101 and the intermittent metal clip 94 . The veneer assembly may or may not also contain panel stiffener plates 96 that engage with the intermittent clips 94 due to the mating configurations of the two elements. These stiffener plates 96 are mechanically fastened to the metal veneer panels 91 via fasteners 97 at prescribed intervals. The veneer assembly 90 may or may not also contain a strip of metal panel veneer 98 located vertically and/or horizontally between the metal veneer panels 91 .
[0050] Other embodiments of the veneer assembly 90 may include other methods of attachment of the assembly 90 to the present invention without departing from the intent of the invention.
[0051] Various modifications may be made to the components of the device 10 of the present invention. Some exemplary modifications to the device are as follows:
The threaded post can be any shape, such as tubular, square, hexagonal, triangular, and the like; Any of the base plate, the panel connecting plate, and the insulation retaining plate, can be flat, but also need not be. For example, any of the plates can have raised surfaces on one face, the other face or both; Any of the base plate, the panel connecting plate, and the insulation retaining plate can be made of a metal such as steel, galvanized steel, aluminum, and the like, a metal alloy, such as cast iron, a plastic, such as a PVC, or any other materials that are suitable for its intended purpose; and Other types and configurations of veneer assemblies may be used in conjunction with the device of the present invention.
[0056] Having described above several aspects of at least one embodiment, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure and are intended to be within the scope of the invention. Accordingly, the foregoing description and drawings are by way of example only. | A device for use in the fastening of a panel or cladding to a wall is disclosed. The device includes a base plate, a panel connecting plate, and a connecting assembly that connects the panel connecting plate to the base plate and that is constructed and arranged so as to provide minimal thermal bridging between the base plate and the panel connecting plate through an insulation layer that covers the base plate and the wall while simultaneously providing structural integrity for attaching the panel or cladding to the wall. | 4 |
[0001] The present embodiments relate to insulated pipeline.
[0002] Insulated pipelines are known which may be externally insulated with lagging or vacuum jacketed. When a cryogenic substance is pressurized its temperature increases and, with cryogenics, an increase in temperature is not desirable. For example, liquid nitrogen (LIN) boils at atmospheric pressure (0 barg) 77.347K (−195.83° C.). However, when the pressure of the liquid nitrogen is increased to 30 barg in a pipline, the boiling temperature of the liquid increases to 126.30° K. (−146.85° C.), an increase of approximately 50° in temperature. This boiling temperature increase of the cryogen causes the cryogen to lose a large portion of its cooling efficiency and increases the risk of evaporation during transportation in the pipeline. Therefore, subcooling the liquid is used to solve the problem but unfortunately, existing pipeline design and construction still permits the liquid cryogen to vaporize after or downstream of the subcooler.
SUMMARY OF THE INVENTION
[0003] The present inventive embodiments maintain the liquid cryogen at a temperature as low as possible during transportation or delivery of the cryogen through the pipeline; increase cooling efficiency of the liquid cryogen so that same can be used for impingement cooling applications where high pressure LIN above 3 barg is used; and, when used with a vacuum pump, reduce the cryogenic temperature below temperatures of LIN at −1 barg at 63.148° K. (−210° C.) therefore increasing the LIN efficiency at impingement.
BRIEF DESCRIPTION OF THE DRAWING
[0004] For a more complete understanding of the present embodiments, reference may be had to the following description taken in conjunction with the drawing Figures, of which:
[0005] FIG. 1 shows a perspective, transparent view of a cryogenic pipeline embodiment of the present invention;
[0006] FIG. 2 shows a cross-section of the pipeline embodiment taken along line 2 - 2 of FIG. 1 ; and
[0007] FIG. 3 shows a cross-sectional side view of the cryogenic pipeline embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0008] Referring to FIGS. 1-3 , a pipeline apparatus of the present embodiments is shown generally at 10 . The apparatus 10 includes a central pipe 12 through which a liquid cryogen such as for example nitrogen (N 2 ), Hydrogen (H), or Helium (He) will flow. The pipe 12 can be constructed from copper or copper alloy material. By way of example, reference to the cryogen will be liquid nitrogen (LIN), although it is understood that other fluids and other cryogenic liquids can flow through the pipe 12 . The central pipe 12 can be of any length and manufactured with turned or bent sections as the application requires.
[0009] Copper fins 14 , 15 or wings are mounted to the central pipe 12 . The fins 14 , 15 can be welded or brazed to an exterior surface of the central pipe 12 . The fins 14 , 15 provide an insulation effect and a pair of passageways 16 , 17 or channels along an exterior of the central pipe 12 . As shown, the fins 14 , 15 substantially extend along the central pipe 12 parallel to a longitudinal axis of said pipe and therefore the fins essentially conform to the shape of the central pipe. The fins 14 , 15 can be formed integral with the central pipe 12 . The combination of the central pipe 12 and the fins 14 , 15 provide a first insert 18 .
[0010] The apparatus 10 includes a tube member 20 having an interior 22 sized and shape to receive the first insert 18 . The tube member 20 can be vacuum jacketed or vacuum insulated, and may be formed from stainless steel, copper or other metallic material. The fins 14 , 15 coact with the tube member 20 to form the passageways 16 , 17 or channels.
[0011] An outer pipe 21 having a shape similar to the central pipe 12 and tube member 20 has a space 23 therein sized and shaped to receive the tube member, as shown for example in FIG. 1 . The space 23 provides an insulation effect with air or a vacuum therein. Alternatively foam or other insulation material can fill the space 23 to provide insulation for the first inset 18 . The combination of the first inset 18 and the tube member 20 form a second insert 25 which is disposed in the space 23 provided by the outer pipe 21 . The outer pipe 21 may be formed from stainless steel, copper or other metallic material.
[0012] At least one spacer 27 and depending upon the length of the apparatus and the bends therein, a plurality of said spacers may be used to provide structural support and spatial arrangement between and among the central pipe 12 , the tube member 20 and the outer pipe 21 . The spacer(s) 27 can be welded into position as shown in FIG. 1 .
[0013] One end 24 of the central pipe 12 is connected to a source (not shown) of high pressure sub-cooled liquid nitrogen at approximately greater than 3 barg. Another end 26 of the central pipe 12 extends through the end cap 30 . The first insert 18 does not consume the entire interior space 22 of the tube 20 . That is, end caps 28 , 30 seal opposed ends of the tube 20 , but provide an entry space 32 and a return space 34 , respectively at opposed ends of the tube member 20 .
[0014] A pipe 35 introduces a low pressure liquid nitrogen 36 for sub-cooling and circulation at less than approximately 1 barg to the entry space 32 . The liquid nitrogen flows in the passageway 16 along the length of the tube member 20 whereupon it reaches the return space 34 before the end cap 30 , at which point the flow turns and proceeds along the passageway 17 . The copper fins 14 , 15 coact to provide the separate passageways 16 , 17 . The flow 43 of the liquid cryogen continues back toward where it was introduced at the entry space 32 to be recirculated again back through the passageway 16 . The flow 43 keeps the temperature of the cryogen liquid in the central pipe 12 as low as possible to prevent vaporization of the liquid.
[0015] A circulation pump 40 and a vacuum pump 42 are in communication with the entry space 32 through a line 46 or conduit to circulate the low pressure LIN 36 along the fins 14 , 15 . A pressure control unit 44 includes relief valves and a pressure gauge and is disposed for communication with the line 46 for the circulating and vacuum pumps 40 , 42 respectively. Although the pressure control unit 44 in FIG. 3 is shown used with the line 46 where the low pressure liquid nitrogen 36 is introduced, the pressure control can also be mounted for use at the return space 34 . The circulation of the LIN 36 is to increase convection from the cold liquid flow through the tube member 20 . It is necessary to only use either the circulation pump 40 or the vacuum pump 42 , depending upon temperature regeneration and the cooling medium (cryogen) being used. The setting at the pressure control unit 44 will therefore control and maintain the pressure in the entry space 32 . During operation, there will be evaporation of the LIN 36 , and any evaporated gas or vapor will have to be released from the apparatus 10 through relief valves at the pressure control unit 44 . For the circulation pump 40 , a set point at the pressure control unit 44 will determine when relief valves are to be opened to exhaust evaporated gas. For the vacuum pump 42 , a set point for the pressure control unit 44 will determine when the pump 42 is to continue to work to release extra pressure created by the evaporation so the set point does not change.
[0016] The sub-cooling LIN 36 is circulated over the fins 14 , 15 in most applications from the uppermost to the lowermost parts of the central pipe 12 , and any gas occurring therefrom will be vented through a pressure relief valve operationally associated with the pressure control 44 .
[0017] As an option, the sub-cooling LIN 36 can be applied under a vacuum to reduce its temperature. A cryogen's boiling point changes with changing pressure, i.e. increasing pressure will therefore increase the boiling temperature of the cryogen. Therefore, reducing the pressure below atmosphere pressure will lead to decreasing the boiling point of the cryogen for subcooling the liquid. Lower temperatures to create a larger difference between the cryogen's boiling temperature and the actual temperature when the cryogen is transported will be required.
[0018] Should the pressure of the sub-cooling LIN 36 exceed a pre-determined pressure, said pressure will be released by the pressure control unit 44 and vented external to the apparatus 10 .
[0019] The present embodiments provide for recycled low pressure liquid (the sub-cooling liquid) to therefore increase the convection of the liquid to correspondingly increase the efficiency of the subcooling. By controlling the pressure of the present embodiments one is able to strictly control the sub-cooling temperatures in the sub-cooling chamber. The sub-cooling liquid can be subjected to a vacuum to provide lower sub-cooling temperatures which would therefore enable more efficient sub-cooled transportation of the cryogens through the pipe. By increasing a surface area of sub-cooler with the fins it is therefore possible to increase the efficiency of the sub-cooling liquid. Finally, the embodiments provide for concurrent sub-cooling and transport of the cryogen.
[0020] It will be understood that the embodiments described herein are merely exemplary, and that one skilled in the art may make variations and modifications without departing from the spirit and scope of the invention. All such variations and modifications are intended to be included within the scope of the invention as described and claimed herein. Further, all embodiments disclosed are not necessarily in the alternative, as various embodiments of the invention may be combined to provide the desired result. | A pipeline apparatus for liquid cryogen includes a first assembly consisting of a first pipe having a first exterior surface and a first passageway for liquid cryogen, and a longitudinal member extending along a portion of the first exterior surface of the first pipe; a second pipe having a second passageway sized and shaped to receive the first assembly therein, the second pipe coacting with the longitudinal member to provide a pair of channels in the second passageway; and a third pipe having a third passageway sized and shaped to receive the second pipe therein, the third pipe spaced apart from the second pipe. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to sewing machines and more particularly to a thread winding mechanism for a sewing machine.
2. Description of the Prior Art
Conventionally, during thread winding operation it has been difficult to recognize whether the rotation of the main shaft of the machine is actually stopped or not. Accordingly, if the operator of the machine erroneously depressed the pedal in spite of the machine being not yet changed to a thread winding condition, the main shaft is then rotated to vertically reciprocate the needle and needle bar, which might result in a dangerous condition if a person has put their hand in the needle operating area of the machine, or the cloth might otherwise be erroneously stitched if it remains within the sewing area.
SUMMARY OF THE INVENTION
It is, therefore, an object of the invention to provide an improved thread winding mechanism, wherein once the bobbin is inserted into the winding shaft, the main shaft as well as a hand wheel is simultaneously prevented from the the rotation thereof.
It is another object of the present invention to provide a compactly constructed and easily operable thread winding mechanism of a sewing machine.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description when considered in connection with the accompanying drawings in which like reference characters designate like or corresponding parts throughout the several views, and wherein:
FIG. 1 shows a cross-sectional view of the present invention;
FIG. 2 is similar to FIG. 1 but showing the thread winding operation being initiated;
FIG. 3 shows a plan view of the invention after removing the arm cover therefrom;
FIG. 4 is similar to FIG. 3 but showing the thread winding mechanism while under operation;
FIG. 5 shows a side cross-sectional view of the present invention; and
FIG. 6 shows a disassembled view of the embodiment of FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the FIGURES, numeral 1 designates an arm of sewing machine which is covered by arm cover 2. A downwardly projecting boss portion 3 is formed integrally with the arm cover 2 at the interior thereof. A guide member 4 is rotatably mounted on boss portion 3 by means of screw bolt 5 for controlling the rotation of a thread winding shaft 6. Guide member 4 further includes a lever member 7 formed integrally with guide member 4 and a bearing means 9 slidably mounted on the outer surface of thread winding shaft 6.
Bearing means 9 has a downwardly extending lever portion 8 while a compression spring 10 is provided between the lever member 7 and the undersurface of bearing means 9 for always biasing bearing means 9 in an upward direction. The upward movement of bearing means 9 relative to the thread winding shaft 6 is limited by a stopper pin 11 provided in lever member 7. Lever member 7 has a recess portion 12 which is provided for preventing lever portion 8 from rotation as well as for guiding the up and down movement thereof.
The upper end of thread winding shaft 6 extends from arm cover 2 for inserting a bobbin 13 (see FIG. 2) thereon. A stopper spring 14 is disposed in the upper end portion of thread winding shaft 6 for preventing the bobbin 13 inserted therein from projecting therefrom during the thread winding operation. Spring 14 is engaged with a recess 15 on shaft 6 when bobbin 13 is inserted into shaft 6. The lower end of the thread winding shaft 6 is secured to a pulley 17 having a rubber roller 16 thereon.
The lowermost end 8a of lever portion 8 is in contact with one end 19a of a lever 19 which is pivotally mounted on a shaft 20 secured to arm cover 2 by a support plate 50. Lever 19 is biased to be in contact with lever portion 8 by means of spring 21 wound around the outer periphery of shaft 20. Another spring 23 is also wound around shaft 20 for biasing another cam lever 22 which is also pivotally mounted on shaft 20.
Due to the biasing force of spring 23 cam lever 22 will be forced to move integrally with the lever 19. Cam lever 22 is engaged with a projection 25 of the lever 19 for restricting the rotational movement of lever 22 in one direction.
A quick motion or snap action spring 28 is provided between a hook 26 of lever member 7 and an inward projection 27 of arm cover 2. The rotational movement of lever member 7 is limited by a stopper 29 secured to arm cover 2. Main or upper shaft 30 is rotatably supported on the arm 1 and one end, i.e. the right end as viewed in FIG. 5, is secured to a hand wheel 40 by means of a nut 41 for unitary rotation. A sleeve member 32 is secured to the main shaft 30 by means of a pin 31 for unitary rotation while a drive pulley 33 is mounted on sleeve member 32 for transmitting rotational torque from a motor (not shown) to main shaft 30 by drive belt means (also not shown) on pulley 33.
A clutch spring 37 is disposed on the outer periphery of sleeve 32 and of boss portion 34 of the pulley 33 in winding manner and one end of spring 37 is secured to a recess 35 provided on sleeve member 32. A cam bushing 36 is disposed along the outer periphery of clutch spring 37 such that spring 37 is positioned between the inner surface of bushing 36 and the outer surfaces of sleeve member 32 and boss portion 34 of pulley 33. The other end of spring 37 is secured to a radial groove 36a provided on the inner end of bushing 36. The assembly including sleeve member 32, pulley 33 clutch spring 37 and bushing 36 is defined in its assembled position by a pair of washers and disk springs 38, 39 provided at both ends of the assembly as clearly shown in FIGS. 5 and 6.
A cover 42 is provided for hand wheel 40 and a stopper 43 is provided on the arm cover adjacent to the upper end of thread winding shaft 6 for stopping the thread winding operation of bobbin 13 and the shaft 6 when the thread is sufficiently wound upon bobbin 13. A plurality of pawls 44 (in the preferred embodiment, four are utilized) are provided at cam bushing 36 for engaging with cam lever 22 when lever 22 is actuated.
In operation, when bobbin 13 is not inserted into thread winding shaft 6, that is, when the sewing machine is under normal sewing operation, the torque from the motor is transmitted to main shaft 30 through pulley 33 and sleeve member 32. At this time, bushing 36 is also rotated by clutch spring 37 disposed between sleeve member 32 and bushing 36. Since hand wheel 40 is secured to main shaft 30, it may rotate when shaft 30 is rotating.
Next, when the operator of the machine wishes to supply thread with the bobbin, bobbin 13 is first inserted into the exposed upper end of thread winding shaft 6 and, upon insertion of bobbin 13, bearing means 9 is forced to be moved downward by the operation of insertion bobbin 13 which is moved down until spring 14 engages with recess 15 of shaft 6 to hold the bobbin in its operative position as shown in FIG. 2. The bearing means 9 is thus moved downward against the force of spring 10 to thereby push down end 19a of lever 19 by lever portion 8 of bearing means 9.
When lever 19 is swung about the shaft 20 in a counterclockwise direction as viewed in FIG. 2 thus overcoming the biasing force of spring 21 thereon, then, due to the rotational movement of lever 19, another cam lever 22 is also initiated to be swung in the same direction to lever 19 through the force of spring 23. The free end of lever 22 is then engaged with one of the pawls 44 provided on the bushing 36 to thereby prevent cam busing 36 from rotation.
Since the inner end of clutch spring 37 is engaged with groove 36a of bushing 36, the frictional engagement between spring 37 and boss 34 of the pulley 33 will be released and thus, the rotational torque of the motor will not be transmitted to main shaft 30 as well as the hand wheel 40 with only pully 33 being in an idle rotation condition. Under such conditions, when thread winding shaft 6 is manually rotated about the axis of screw bolt 5 from the position of FIG. 3 to that of FIG. 4, the rubber pulley 16 secured to shaft 6 is frictionally engaged with pulley 33 to initiate unitary rotation therewith. It should be noted that an arcuate slot is provided on arm cover 2 for allowing shaft 6 to move between the positions of FIG. 3 and FIG. 4.
After the thread is sufficiently wound around bobbin 13, the thread wound bobbin comes in contact with stopper 43 to prevent it from further winding operation as in a conventional manner.
Thus, according to the present invention, once the bobbin is inserted into thread winding shaft 6, main shaft 30 simultaneously stops its rotation to prevent any danger of the operator erroneously actuating the motor by actuation of the motor of the machine.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A thread winding mechanism including a thread winding shaft and a clutch member for disconnecting a torque transmission between a main shaft of a sewing machine and a drive pulley. Once the bobbin is manually inserted into the thread winding shaft the clutch member is automatically actuated to disconnect the main shaft from the drive pulley for preparation of the thread winding operation. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a divisional of U.S. patent application Ser. No. 12/496,348, filed Jul. 1, 2009, which is a continuation of U.S. patent application Ser. No. 11/703,358, filed Feb. 5, 2007 and issued as U.S. Pat. No. 7,579,510 on Aug. 25, 2009, which claims priority to U.S. Provisional Patent Application No. 60/765,115, filed Feb. 3, 2006. The entire contents of each are incorporated by reference herein.
BACKGROUND OF THE INVENTION
This invention generally relates to carbon-carbon coupling and, more particularly, to methods for converting hydrocarbon feedstocks into useful products.
Scientists have long sought efficient ways to convert methane and other hydrocarbons into longer chain hydrocarbons, olefins, aromatic hydrocarbons, and other products. CH bond activation has been the focus of intense research for decades, with mixed results. More efficient processes could create value in a number of ways, including facilitating the utilization of remotely located hydrocarbon feedstocks (such as stranded natural gas) through conversion into more easily transportable and useful fuels and feedstocks, and allowing the use of inexpensive feedstocks (e.g., methane and other light hydrocarbons) for end products often made from higher hydrocarbons.
U.S. Pat. No. 6,525,230 discloses methods of converting alkanes to other compounds using a “zone reactor” comprised of a hollow, unsegregated interior defining first, second, and third zones. Oxygen reacts with metal bromide in the first zone to provide bromine; bromine reacts with the alkane in the second zone to form alkyl bromide and hydrogen bromide; and the alkyl bromide reacts with metal oxide in the third zone to form the corresponding product. In one embodiment, the flow of gases through the reactor is reversed to convert the metal oxide back to metal bromide and to convert the metal bromide back to the metal oxide. The reactor is essentially operated in a cyclic mode.
U.S. Pat. No. 6,452,058 discloses an oxidative halogenation process for producing alkyl halides from an alkane, hydrogen halide, and, preferably, oxygen, using a rare earth halide or oxyhalide catalyst. The alternative of using molecular halogen is also mentioned. Other patents, such as U.S. Pat. Nos. 3,172,915, 3,657,367, 4,769,504, and 4,795,843, disclose the use of metal halide catalysts for oxidative halogenation of alkanes. Oxidative halogenation, however, has several disadvantages, including the production of perhalogenated products and an unacceptable quantity of deep oxidation products (CO and CO 2 ).
Three published U.S. patent applications, Pub. Nos. 2005/0234276, 2005/0234277, and 2006/0100469 (each to Waycuilis), describe bromine-based processes for converting gaseous alkanes to liquid hydrocarbons. Several basic steps are described, including (1) reacting bromine with alkanes to produce alkyl bromides and hydrobromic acid (bromination), (2) reacting the alkyl bromide and hydrobromic acid product with a crystalline alumino-silicate catalyst to form higher molecular weight hydrocarbons and hydrobromic acid (coupling), (3) neutralizing the hydrobromic acid by reaction with an aqueous solution of partially oxidized metal bromide salts (as metal oxides/oxybromides/bromides) to produce a metal bromide salt and water in an aqueous solution, or by reaction of the hydrobromic acid with air over a metal bromide catalyst, and (4) regenerating bromine by reaction of the metal bromide salt with oxygen to yield bromine and an oxidized salt. Potential drawbacks of the processes include low methane conversions; short space-times and the resulting potential for less than 100% bromine conversion; wasteful overbromination of ethane, propane, and higher alkanes, resulting in the formation of dibromomethane and other polybrominated alkanes, which will likely form coke under the disclosed reaction conditions; comparatively low alkyl bromide conversions; the need to separate the hydrocarbon product stream from an aqueous hydrohalic acid stream; and inadequate capture of halogen during the regeneration of the catalyst to remove halogen-containing coke. In addition, the proposed venting of this bromine-containing stream is both economically and environmentally unacceptable.
The Waycuilis process also apparently requires operation at relatively low temperatures to prevent significant selectivity to methane. The likely result would be incomplete conversion of alkyl bromide species and, because the described process relies on stream splitting to recover products, a considerable amount of unconverted alkyl bromides would likely leave the process with the products. This represents an unacceptable loss of bromine (as unconverted methyl bromide) and a reduced carbon efficiency.
The neutralization of hydrobromic acid by reaction with an aqueous solution of partially oxidized metal bromide salts and subsequent reaction of the metal bromide salts formed with oxygen to yield bromine and an oxidized salt, as disclosed by Waycuilis, also has a number of disadvantages. First, any carbon dioxide present will form carbonates in the slurry, which will not be regenerable. Second, the maximum temperature is limited due to pressure increases which are intolerable above approximately 200° C., thus preventing complete recovery of halogen. Third, although the use of redox-active metal oxides (e.g., oxides of V, Cr, Mn, Fe, Co, Ce, and Cu) will contribute to molecular bromine formation during the neutralization of hydrobromic acid, incomplete HBr conversion due to the use of a solid bromide salt will in turn result in a significant loss of bromine from the system (in the water phase). Provided an excess of air was used, the bromide salt might eventually be converted to the oxide form, stopping any further loss of HBr in the water discard.
To separate water from bromine, Waycuilis discloses the use of condensation and phase separation to produce semi-dry liquid bromine and a water/bromine mixture. Other means for separating water from bromine, such as using an inert gas to strip the bromine from the water phase or using adsorption-based methods have also been proposed by others; however, such methods are minimally effective and result in a significant overall loss of halogen.
The prior art oxychlorination process first removes the water from HCl (a costly step) and then reacts the HCl with oxygen and hydrocarbon directly. Oxychlorination processes rely on the separation of HCl from the unreacted alkanes and higher hydrocarbon products by using water absorption, and subsequent recovery of anhydrous HCl from the aqueous hydrochloric acid. U.S. Pat. No. 2,220,570 discloses a process and apparatus for the absorption of HCl in water where the heat of absorption is dissipated by contacting the HCl gas with ambient air, and also by the vaporization of water. A process for producing aqueous hydrochloric acid with a concentration of at least 35.5 wt % by absorbing gaseous HCl in water is disclosed in U.S. Pat. No. 4,488,884. U.S. Pat. No. 3,779,870 teaches a process for the recovery of anhydrous HCl gas by extractive distillation using a chloride salt. U.S. Pat. No. 4,259,309 teaches a method for producing gaseous HCl from dilute aqueous HCl using an amine together with an inert water-immiscible solvent.
Although researchers have made some progress in the search for more efficient CH bond activation pathways for converting natural gas and other hydrocarbon feedstocks into fuels and other products, there remains a tremendous need for a continuous, economically viable, and more efficient process.
SUMMARY OF THE INVENTION
This invention generally relates to carbon-carbon coupling and, more particularly, to methods for converting hydrocarbon feedstocks into useful products.
An embodiment provides a method comprising providing a halogen stream; providing a first alkane stream; reacting at least a portion of the halogen stream with at least a portion of the first alkane stream to form a halogenated stream, wherein the halogenated stream comprises alkyl monohalides, alkyl polyhalides, and a hydrogen halide; providing a second alkane stream; and reacting at least a portion of the second alkane stream with at least a portion of the alkyl polyhalides to create at least some additional alkyl monohalides.
Another embodiment provides a system for forming hydrocarbons comprising a halogenation reactor, wherein the halogenation reactor receives a quantity of halide and a first quantity of alkane and produces a halogenated product; a reproportionation reactor, wherein the reproportionation reactor receives the halogenated product and a second quantity of alkane and produces at least some alkyl monohalide product and a quantity of hydrogen halide; and a oligomerization reactor comprising a catalyst, wherein the oligomerization reactor receives alkyl monohalide and produces a quantity of hydrocarbon product and a second quantity of hydrogen halide.
Yet another embodiment provides a method comprising providing an alkyl halide stream comprising alkyl monohalides, alkyl polyhalides, and a hydrogen halide; providing a first alkane stream; reacting at least a portion of the first alkane stream with at least a portion of the alkyl halide stream to create at least some additional alkyl monohalides; contacting at least some of the alkyl monohalides and at least some of the additional alkyl monohalides with a catalyst to form a product stream that comprises higher hydrocarbons, hydrogen halide, and any unreacted portion of the first alkane stream; separating the unreacted portion of the first alkane stream from the product stream; providing a halogen stream; and reacting at least some of the unreacted portion of the first alkane stream separated from the product stream with the halogen to form the alkyl halide stream.
Still another embodiment provides a method comprising providing an alkyl halide stream; contacting at least some of the alkyl halides with a catalyst to form a product stream that comprises higher hydrocarbons and hydrogen halide; separating the hydrogen halide from the product stream; and reacting the hydrogen halide with a source of oxygen in the presence of a cerium oxide catalyst to generate a corresponding halogen.
The features and advantages of the present invention will be apparent to those skilled in the art. While numerous changes may be made by those skilled in the art, such changes are within the spirit of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of one embodiment of a continuous process for converting methane or natural gas into hydrocarbon chemicals according to the invention;
FIG. 2 is a schematic view of one embodiment of a continuous process for converting methane or natural gas into hydrocarbon fuels according to the invention;
FIG. 3 is a schematic view of a subprocess for reproportionating polyhalides according to an alternate embodiment of the invention;
FIG. 4 is a schematic view of one embodiment of a monobromide separation column, for use in the practice of the invention;
FIG. 5 is a schematic view of one embodiment of an extractive distillation system, for use in the practice of the invention;
FIG. 6 is a simplified block diagram of one embodiment of a continuous process for converting alkanes into hydrocarbon products according to the invention, wherein water is separated from hydrocarbon products; and
FIG. 7 is a simplified block diagram of one embodiment of a continuous process for converting alkanes into hydrocarbon products according to the invention, wherein water is separated after the alkane bromination step.
FIG. 8 is a graph of bromobenzene conversion and benzene yield as a function of time, for an experiment conducted according to one embodiment of the invention; and
FIG. 9 is a graph of catalyst effectiveness as a function of time, for an experiment conducted according to one embodiment of the invention.
DETAILED DESCRIPTION
This invention generally relates to carbon-carbon coupling and, more particularly, to methods for converting hydrocarbon feedstocks into useful products.
The present invention provides a chemical process that enables natural gas and other hydrocarbon feedstocks to be converted into higher molecular weight hydrocarbon products, using molecular halogen to activate C—H bonds in the feedstock. According to one aspect of the invention, a continuous process for converting a hydrocarbon feedstock into one or more higher hydrocarbons comprises the steps of (a) forming alkyl halides by reacting molecular halogen with a hydrocarbon feedstock (preferably a feedstock containing methane), under process conditions sufficient to form alkyl halides and hydrogen halide, whereby substantially all of the molecular halogen is consumed; (b) forming reproportionated alkyl halides by reacting some or all of the alkyl halides with an alkane feed, whereby the fraction of monohalogenated hydrocarbons present is increased; (c) contacting the reproportionated alkyl halides with a first catalyst under process conditions sufficient to form higher hydrocarbons and additional hydrogen halide; (d) separating the higher hydrocarbons from the hydrogen halide; (e) regenerating molecular halogen by contacting the hydrogen halide with a second catalyst in the presence of a source of oxygen, under process conditions sufficient to form molecular halogen and water; (f) separating the molecular halogen from water to allow reuse of the halogen; and (g) repeating steps (a) through (f) a desired number of times. These steps can be carried out in the order presented or, alternatively, in a different order.
According to a second aspect of the invention, a continuous process for converting a hydrocarbon feedstock into one or more higher hydrocarbons comprises the steps of (a) forming alkyl halides by reacting molecular halogen with a hydrocarbon feedstock containing methane in a halogenation reactor, under process conditions sufficient to form alkyl halides and hydrogen halide, whereby substantially all of the molecular halogen is consumed; (b) separating unreacted methane from the alkyl halides and directing it back into the halogenation reactor; (c) forming reproportionated alkyl halides by reacting some or all, of the alkyl halides with an alkane feed containing at least 1% by volume of one or more C2-C5 hydrocarbons, whereby the fraction of monohalogenated hydrocarbons present is increased; (d) contacting the reproportionated alkyl halides with a first catalyst under process conditions sufficient to form higher hydrocarbons and additional hydrogen halide; (e) separating the higher hydrocarbons from the hydrogen halide; (f) regenerating molecular halogen by contacting the hydrogen halide with a second catalyst in the presence of a source of oxygen, under process conditions sufficient to form molecular halogen and water; (g) separating the molecular halogen from water to allow reuse of the halogen; and (h) repeating steps (a) through (g) a desired number of times.
In each of the aspects and embodiments of the invention, it is intended that the alkyl halides formed in step (a) can be all the same (e.g., 100% bromomethane) or, more typically, different (e.g., mixtures of bromomethane, dibromomethane, dibromoethane, etc). Similarly, it is contemplated that the “higher hydrocarbons” formed in step (c) can be all the same (e.g., 100% isooctane) or, more typically, different (e.g., mixtures of aliphatic and/or aromatic compounds). As used herein, the term “higher hydrocarbons” refers to hydrocarbons having a greater number of carbon atoms than one or more components of the hydrocarbon feedstock, as well as olefinic hydrocarbons having the same or a greater number of carbon atoms as one or more components of the hydrocarbon feedstock. For instance, if the feedstock is natural gas—typically a mixture of light hydrocarbons, predominately methane, with lesser amounts of ethane, propane, and butane, and even smaller amounts of longer chain hydrocarbons such as pentane, hexane, etc.—the “higher hydrocarbon(s)” produced according to the invention can include a C 2 or higher hydrocarbon, such as ethane, propane, butane, C 5+ hydrocarbons, aromatic hydrocarbons, etc., and optionally ethylene, propylene, and/or longer olefins The term “light hydrocarbons” (sometimes abbreviated “LHCs”) refers to C 1 -C 4 hydrocarbons, e.g., methane, ethane, propane, ethylene, propylene, butanes, and butenes, all of which are normally gases at room temperature and atmospheric pressure.
Nonlimiting examples of hydrocarbon feedstocks appropriate for use in the present invention include alkanes, e.g., methane, ethane, propane, and even larger alkanes; olefins; natural gas and other mixtures of hydrocarbons. In most cases, the feedstock will be primarily aliphatic in nature. Certain oil refinery processes yield light hydrocarbon streams (so-called “light-ends,” typically a mixture of C 1 -C 3 hydrocarbons), which can be used with or without added methane as the hydrocarbon feedstock in one embodiment of the invention.
Representative halogens include bromine (Br 2 ) and chlorine (Cl 2 ). It is also contemplated that fluorine and iodine can be used, though not necessarily with equivalent results. Some of the problems associated with fluorine can likely be addressed by using dilute streams of fluorine (e.g., fluorine gas carried by helium, nitrogen, or other diluent). It is expected, however, that more vigorous reaction conditions will be required for alkyl fluorides to couple and form higher hydrocarbons, due to the strength of the fluorine-carbon bond. Similarly, problems associated with iodine (such as the endothermic nature of certain iodine reactions) can likely be addressed by carrying out the halogenation and/or coupling reactions at higher temperatures and/or pressures. The use of bromine or chlorine is preferred, with bromine being most preferred.
FIGS. 1 and 2 schematically illustrate two nonlimiting embodiments of a process according to the invention, with FIG. 1 depicting a process for making hydrocarbon chemicals (e.g., benzene, toluene, xylenes, other aromatic compounds, etc.), and FIG. 2 depicting a process for making fuel-grade hydrocarbons, e.g., hydrocarbons comprising a predominant amount of C 5 and higher aliphatic hydrocarbons and (optionally) aromatic hydrocarbons. The primary difference in the two embodiments is that the process depicted in FIG. 2 lacks the first separation unit (SEP I) and does not return polybrominated species to the bromination reactor for “reproportionation.” In the scheme shown in FIG. 2 , the amount of polybromides produced is reduced significantly by introducing light gasses into the bromination reactor. The polybromides (from methane bromination) react with the light gasses to form monobromoalkanes. For convenience, the figures depict a bromine-based process. In alternate embodiments of the invention, however, chlorine or other halogens are used.
As shown in FIG. 1 , natural gas (or another hydrocarbon feedstock) and molecular bromine are carried by separate lines 1 , 2 into a heated bromination reactor 3 and allowed to react. Products (HBr, alkyl bromides, optionally olefins), and possibly unreacted hydrocarbons, exit the reactor and are carried by a line 4 into a first separation unit 5 (SEP I), where monobrominated hydrocarbons and HBr are separated from polybrominated hydrocarbons. The polybromides are carried by a line 6 back to the bromination reactor, where they undergo “reproportionation” with methane and/or other light hydrocarbons, which are present in the natural gas and/or introduced to the bromination reactor as described below.
Reproportionation of the polybromides formed during the bromination reaction enriches the outlet stream with monobromides and olefinic species, and reduces the amount of polybrominated hydrocarbons that enter the coupling reactor. This, in turn, reduces the amount of coke that forms during the carbon-carbon coupling reactions. For large scale production of aromatic hydrocarbons, it is possible to employ additional separation units, which can further purify the feed stream to the coupling reactor by separating and recycling the polybromides, thereby reducing the amount of coke and the overall bromine requirement.
Unreacted hydrocarbon feedstock, HBr, monobromides, and (optionally) olefins formed in the bromination reactor are carried by a line 7 , through a heat exchanger 8 , and enter a heated coupling reactor 9 , where the monobromides (and, optionally, any olefins present) react in the presence of a coupling catalyst to form higher hydrocarbons. HBr, higher hydrocarbons, and (possibly) unreacted hydrocarbons and alkyl bromides exit the coupling reactor and are carried by a line 10 , through another heat exchanger 11 , and enter an HBr absorption unit 12 . Water is introduced into the unit through a separate line 13 . HBr is absorbed in this unit, which may be a packed column or other gas-liquid contacting device. The effluent, containing liquid hydrocarbons and aqueous HBr, is carried by a line 14 to a liquid-liquid splitter 15 , which phase-separates liquid hydrocarbons from the aqueous HBr stream. The liquid hydrocarbon products are then carried by a line 16 to a product clean-up unit 17 to yield final hydrocarbon products.
After HBr is separated from the hydrocarbon products and unreacted methane (and any other light hydrocarbons that may be present) in the HBr absorption unit, the methane (and other light hydrocarbons, if any) is carried by a line 18 into a second separation unit 19 (SEP II), which employs pressure- or temperature-swing adsorption, membrane-based separation, cryogenic distillation (preferable for large scale production), or another suitable separation technology. Methane, and possibly other light hydrocarbons, are returned to the bromination reactor via one or more lines 20 , 21 . In the embodiment shown, methane is directed to an upstream region or “zone” of the bromination reactor, while other light hydrocarbons are directed to a mid- or downstream zone of the reactor (the latter to facilitate reproportionation of polybromides).
The aqueous HBr stream that evolves from the liquid-liquid splitter is carried by a line 22 to a bromine generation unit 23 . Oxygen, air, or oxygen-enriched gas is also fed into the unit through a separate line 24 . Bromine is regenerated by reacting HBr with oxygen in the presence of a suitable catalyst. The resulting stream contains water, molecular bromine, oxygen, nitrogen (if air was used as the source of oxygen), and possibly other gases. This product stream is carried by a line 25 through a heat exchanger 26 into a flash vaporization unit 27 , which separates most of the molecular bromine from water, oxygen, nitrogen, and other gases (if any) that are present. Molecular bromine, either as a liquid or vapor (and containing no more than a trace of H 2 O), is carried by a line 28 to a heat exchanger 29 , and then returned to the bromination reactor.
Water from the flash vaporization unit (containing up to 3 wt % of molecular bromine) is sent by a line 30 to a distillation unit 31 , which yields water as the bottoms stream and bromine or bromine-water azeotrope as a distillate. The distillate is returned through a line 32 back to the flash vaporization unit.
The gaseous products of the flash vaporization unit (e.g., oxygen, nitrogen, optionally other gases, and no more than a minor or trace amount of bromine) are carried by a line 33 to a bromine scavenging unit 34 , which separates molecular bromine from the other gases. The recovered bromine is then carried by a line 35 through a heat exchanger 29 and reintroduced into the bromination reactor. The amount of bromine entering the scavenger can be further reduced by increasing the amount of bromine recovered in the flash step by employing brine solutions and direct contact cooling to allow the use of temperatures below 0° C. The other gases (e.g., nitrogen, oxygen) can be vented to the atmosphere.
Various embodiments and features of individual subprocesses and other improvements for carrying out the invention will now be described in more detail.
Bromination
Bromination of the hydrocarbon feedstock is carried out in a fixed bed, fluidized bed, or other suitable reactor, at a temperature and pressure such that the bromination products and reactants are gases, for example, 1-50 atm, 150-600° C., more preferably 400-600° C., even more preferably, 450-515° C., with a residence time of 1-60 seconds, more preferably 1-15 seconds. Higher temperatures tend to favor coke formation, while low temperatures require larger reactors. Using a fluidized bed offers the advantage of improved heat transfer.
Alkane bromination can be initiated using heat or light, with thermal means being preferred. In one embodiment, the reactor also contains a halogenation catalyst, such as a zeolite, amorphous alumino-silicate, acidic zirconia, tungstates, solid phosphoric acids, metal oxides, mixed metal oxides, metal halides, mixed metal halides (the metal in such cases being, e.g., nickel, copper, cerium, cobalt, etc.), and/or or other catalysts as described, e.g., in U.S. Pat. Nos. 3,935,289 and 4,971,664. In an alternate embodiment, the reactor contains a porous or non-porous inert material that provides sufficient surface area to retain coke formed in the reactor and prevent it from escaping. The inert material may also promote the formation of polyhalogenated hydrocarbons, such as tribromopropane. In still another embodiment, both a catalyst and an inert material are provided in the reactor. Optionally, the reactor contains different regions or zones to allow, in or more zones, complete conversion of molecular bromine to produce alkyl bromides and hydrogen bromide.
The bromination reaction can also be carried out in the presence of an isomerization catalyst, such as a metal bromide (e.g., NaBr, KBr, CuBr, NiBr 2 , MgBr 2 , CaBr 2 ), metal oxide (e.g., SiO 2 , ZrO 2 , Al 2 O 3 ), or metal (Pt, Pd, Ru, Ir, Rh) to help generate the desired brominated isomer(s). Since isomerization and bromination conditions are similar, the bromination and isomerization can be carried out in the same reactor vessel. Alternatively, a separate isomerization reactor can be utilized, located downstream of the bromination reactor and upstream of the coupling reactor.
Reproportionation
In some embodiments, a key feature of the invention is the “reproportionation” of polyhalogenated hydrocarbons (polyhalides), i.e., halogenated hydrocarbons containing two or more halogen atoms per molecule. Monohalogenated alkanes (monohalides) created during the halogenation reaction are desirable as predominant reactant species for subsequent coupling reactions and formation of higher molecular weight hydrocarbons. For certain product selectivities, polyhalogenated alkanes may be desirable. Reproportionation allows a desired enrichment of monohalides to be achieved by reacting polyhalogenated alkyl halides with nonhalogenated alkanes, generally in the substantial absence of molecular halogens, to control the ratio of mono-to-polyhalogenated species. For example, dibromomethane is reacted with methane to produce methyl bromide; dibromomethane is reacted with propane to produce methyl bromide and propyl bromide and/or propylene; and so forth.
Reactive reproportionation is accomplished by allowing the hydrocarbon feedstock and/or recycled alkanes to react with polyhalogenated species from the halogenation reactor, preferably in the substantial absence of molecular halogen. As a practical matter, substantially all of the molecular halogen entering the halogenation reactor is quickly consumed, forming mono- and polyhalides; therefore reproportionation of higher bromides can be accomplished simply by introducing polybromides into a mid- or downstream region or “zone” of the halogenation reactor, optionally heated to a temperature that differs from the temperature of the rest of the reactor.
Alternatively, reproportionation can be carried out in a separate “reproportionation reactor,” where polyhalides and unhalogenatated alkanes are allowed to react, preferably in the substantial absence of molecular halogen. FIG. 3 illustrates one such embodiment where, for clarity, only significant system elements are shown. As in FIG. 1 , natural gas or another hydrocarbon feedstock and molecular bromine are carried by separate lines 1 , 2 to a heated bromination reactor 3 and allowed to react. Products (HBr, alkyl bromides) and possibly unreacted hydrocarbons, exit the reactor and are carried by a line 4 into a first separation unit 5 (SEP I), where monobrominated hydrocarbons and HBr are separated from polybrominated hydrocarbons. The monobromides, HBr, and possibly unreacted hydrocarbons are carried by a line 7 , through a heat exchanger 8 , to a coupling reactor 9 , and allowed to react, as shown in FIG. 1 . The polybromides are carried by a line 6 to a reproportionation reactor 36 . Additional natural gas or other alkane feedstock is also introduced into the reproportionation reactor, via a line 37 . Polybromides react with unbrominated alkanes in the reproportionation reactor to form monobromides, which are carried by a line 38 to the coupling reactor 9 , after first passing through a heat exchanger.
In another embodiment of the invention (not shown), where the hydrocarbon feedstock comprises natural gas containing a considerable amount of C2 and higher hydrocarbons, the “fresh” natural gas feed is introduced directly into the reproportionation reactor, and recycled methane (which passes through the reproportionation reactor unconverted) is carried back into the halogenation reactor.
Reproportionation is thermally driven and/or facilitated by use of a catalyst. Nonlimiting examples of suitable catalysts include metal oxides, metal halides, and zeolites. U.S. Pat. No. 4,654,449 discloses the reproportionation of polyhalogenated alkanes with alkanes using an acidic zeolite catalyst. U.S. Pat. Nos. 2,979,541 and 3,026,361 disclose the use of carbon tetrachloride as a chlorinating agent for methane, ethane, propane and their chlorinated analogues. All three patents are incorporated by reference herein in their entirety. Using reproportionation in the context of a continuous process for the enrichment of reactive feed stocks for the production of higher hydrocarbons has never been disclosed to our knowledge.
Reproportionation of C1-C5 alkanes with dibromomethane and/or other polybromides occurs at temperatures ranging from 350 to 550° C., with the optimal temperature depending on the polybromide(s) that are present and the alkane(s) being brominated. In addition, reproportionation proceeds more quickly at elevated pressures (e.g., 2-30 bar). By achieving a high initial methane conversion in the halogenation reactor, substantial amounts of di- and tribromomethane are created; those species can then be used as bromination reagents in the reproportionation step. Using di- and tribromomethane allows for controlled bromination of C1-C5 alkanes to monobrominated C1-C5 bromoalkanes and C2-C5 olefins. Reproportionation of di- and tribromomethane facilitates high initial methane conversion during bromination, which should reduce the methane recycle flow rate and enrich the reactant gas stream with C2-C5 monobromoalkanes and olefins, which couple to liquid products over a variety of catalysts, including zeolites. This is a major new process advance.
In another embodiment of the invention, reproportionation is carried out without first separating the polyhalides in a separation unit. This is facilitated by packing the “reproportionation zone” with a catalyst, such as a zeolite, that allows the reaction to occur at a reduced temperature. For example, although propane reacts with dibromomethane to form bromomethane and bromopropane (an example of “reproportionation”), the reaction does not occur to an appreciable degree at temperatures below about 500° C. The use of a zeolite may allow reproportionation to occur at a reduced temperature, enabling species such as methane and ethane to be brominated in one zone of the reactor, and di-, tri-, and other polybromides to be reproportionated in another zone of the reactor.
Bromine Recovery During Decoking
Inevitably, coke formation will occur in the halogenation and reproportionation processes. If catalysts are used in the reactor(s) or reactor zone(s), the catalysts may be deactivated by the coke; therefore, periodic removal of the carbonaceous deposits is required. In addition, we have discovered that, within the coke that is formed, bromine may also be found, and it is highly desirable that this bromine be recovered in order to minimize loss of bromine in the overall process, which is important for both economic and environmental reasons.
Several forms of bromides are present: HBr, organic bromides such as methyl bromide and dibromomethane, and molecular bromine. The invention provides means for recovering this bromine from the decoking process. In a preferred embodiment, a given reactor is switched off-line and air or oxygen is introduced to combust the carbon deposits and produce HBr from the residual bromine residues. The effluent gas is added to the air (or oxygen) reactant stream fed to the bromine generation reactor, thereby facilitating complete bromine recovery. This process is repeated periodically.
While a given reactor is off-line, the overall process can, nevertheless, be operated without interruption by using a reserve reactor, which is arranged in parallel with its counterpart reactor. For example, twin bromination reactors and twin coupling reactors can be utilized, with process gasses being diverted away from one, but not both, bromination reactors (or coupling reactors) when a decoking operation is desired. The use of a fluidized bed may reduce coke formation and facilitate the removal of heat and catalyst regeneration.
Another embodiment of the decoking process involves non-oxidative decoking using an alkane or mixture of alkanes, which may reduce both the loss of adsorbed products and the oxygen requirement of the process. In another embodiment of the decoking process, an oxidant such as oxygen, air, or enriched air is co-fed into the bromination section to convert the coke into carbon dioxide and/or carbon monoxide during the bromination reaction, thus eliminating or reducing the off-line decoking requirement.
Alkyl Halide Separation
The presence of large concentrations of polyhalogenated species in the feed to the coupling reactor can result in an increase in coke formation. In many applications, such as the production of aromatics and light olefins, it is desirable to feed only monohalides to the coupling reactor to improve the conversion to products. In one embodiment of the invention, a specific separation step is added between the halogenation/reproportionation reactor(s) and the coupling reactor.
For example, a distillation column and associated heat exchangers (“SEP I” in FIGS. 1 and 2 ) can be used to separate the monobromides from the polybrominated species by utilizing the large difference in boiling points of the compounds. The polybrominated species that are recovered as the bottoms stream can be reproportionated with alkanes to form monobromide species and olefins, either in the bromination reactor or in a separate reproportionation reactor. The distillation column can be operated at any pressure of from 1 to 50 bar. The higher pressures allow higher condenser temperatures to be used, thereby reducing the refrigeration requirement.
FIG. 4 illustrates one embodiment of a separation unit for separating monobromides from polybrominated species. Alkyl bromides from the bromination reactor are cooled by passing through a heat exchanger 50 , and then provided to a distillation column 51 equipped with two heat exchangers 52 and 53 . At the bottom of the column, heat exchanger 52 acts as a reboiler, while at the top of the column heat exchanger 53 acts as a partial condenser. This configuration allows a liquid “bottoms” enriched in polybromides (and containing no more than a minor amount of monobromides) to be withdrawn from the distillation column. The polybromides are passed through another heat exchanger 54 to convert them back to a gas before they are returned to the bromination reactor (or sent to a separate reproportionation reactor) for reproportionation with unbrominated alkanes. At the top of the column, partial reflux of the liquid from the reflux drum is facilitated by the heat exchanger 53 , yielding a vapor enriched in lighter components including methane and HBr, and a liquid stream comprised of monobromides and HBr (and containing no more than a minor amount of polybromides).
Alternate distillation configurations include a side stream column with and without a side stream rectifier or stripper. If the feed from the bromination reactor contains water, the bottoms stream from the distillation column will also contain water, and a liquid-liquid phase split on the bottoms stream can be used to separate water from the polybrominated species. Due to the presence of HBr in the water stream, it can either be sent to a HBr absorption column or to the bromine generation reactor.
Catalytic Coupling of Alkyl Halides to Higher Molecular Weight Products
The alkyl halides produced in the halogenation/reproportionation step are reacted over a catalyst to produce higher hydrocarbons and hydrogen halide. The reactant feed can also contain hydrogen halide and unhalogenated alkanes from the bromination reactor. According to the invention, any of a number of catalysts are used to facilitate the formation of higher hydrocarbon products from halogenated hydrocarbons. Nonlimiting examples include non-crystalline alumino silicates (amorphous solid acids), tungsten/zirconia super acids, sulfated zirconia, alumino phosphates such as SAPO-34 and its framework-substituted analogues (substituted with, e.g., Ni or Mn), Zeolites, such as ZSM-5 and its ion-exchanged analogs, and framework substituted ZSM-5 (substituted with Ti, Fe, Ti+Fe, B, or Ga). Preferred catalysts for producing liquid-at-room-temperature hydrocarbons include ion-exchanged ZSM-5 having a SiO 2 /Al 2 O 3 ratio below 300, preferably below 100, and most preferably 30 or below. Nonlimiting examples of preferred exchanged ions include ions of Ag, Ba, Bi, Ca, Fe, Li, Mg, Sr, K, Na, Rb, Mn, Co, Ni, Cu, Ru, Pb, Pd, Pt, and Ce. These ions can be exchanged as pure salts or as mixtures of salts. The preparation of doped zeolites and their use as carbon-carbon coupling catalysts is described in Patent Publication No. US 2005/0171393 A1, at pages 4-5, which is incorporated by reference herein in its entirety.
In one embodiment of the invention a Mn-exchanged ZSM-5 zeolite having a SiO 2 /Al 2 O 3 ratio of 30 is used as the coupling catalyst. Under certain process conditions, it can produce a tailored selectivity of liquid hydrocarbon products.
Coupling of haloalkanes preferably is carried out in a fixed bed, fluidized bed, or other suitable reactor, at a suitable temperature (e.g., 150-600° C., preferably 275-425° C.) and pressure (e.g., 0.1 to 35 atm) and a residence time (.tau.) of from 1-45 seconds. In general, a relatively long residence time favors conversion of reactants to products, as well as product selectivity, while a short residence time means higher throughput and (possibly) improved economics. It is possible to direct product selectivity by changing the catalyst, altering the reaction temperature, and/or altering the residence time in the reactor. For example, at a moderate residence time of 10 seconds and a moderate temperature of 350° C., xylene and mesitylenes are the predominant components of the aromatic fraction (benzene+toluene+xylenes+mesitylenes; “BTXM”) produced when the product of a methane bromination reaction is fed into a coupling reactor packed with a metal-ion-impregnated ZSM-5 catalyst, where the impregnation metal is Ag, Ba, Bi, Ca, Co, Cu, Fe, La, Li, Mg, Mn, Ni, Pb, Pd, or Sr, and the ZSM-5 catalyst is Zeolyst CBV 58, 2314, 3024, 5524, or 8014, (available from Zeolyst International (Valley Forge, Pa.)). At a reaction temperature of 425° C. and a residence time of 40 seconds, toluene and benzene are the predominant products of the BTXM fraction. Product selectivity can also be varied by controlling the concentration of dibromomethane produced or fed into the coupling reactor. Removal of reaction heat and continuous decoking and catalyst regeneration using a fluidized bed reactor configuration for the coupling reactor is anticipated in some facilities.
In one embodiment, the coupling reaction is carried out in a pair of coupling reactors, arranged in parallel. This allows the overall process to be run continuously, without interruption, even if one of the coupling reactors is taken off line for decoking or for some other reason. Similar redundancies can be utilized in the bromination, product separation, halogen generation, and other units used in the overall process.
Hydrocarbon Product Separation and Halogen Recovery
The coupling products include higher hydrocarbons and HBr. In the embodiments shown in FIGS. 1 and 2 , products that exit the coupling reactor are first cooled in a heat exchanger and then sent to an absorption column. HBr is absorbed in water using a packed column or other contacting device. Input water and the product stream can be contacted either in a co-current or counter-current flow, with the counter-current flow preferred for its improved efficiency. HBr absorption can be carried out either substantially adiabatically or substantially isothermally. In one embodiment, the concentration of hydrobromic acid after absorption ranges from 5 to 70 wt %, with a preferred range of 20 to 50 wt %. The operating pressure is 1 to 50 bar, more preferably 1 to 30 bar. In the laboratory, a glass column or glass-lined column with ceramic or glass packing can be used. In a pilot or commercial plant, one or more durable, corrosion-resistant materials (described below) are utilized.
In one embodiment of the invention, the hydrocarbon products are recovered as a liquid from the HBr absorption column. This liquid hydrocarbon stream is phase-separated from the aqueous HBr stream using a liquid-liquid splitter and sent to the product cleanup unit. In another embodiment, the hydrocarbon products are recovered from the HBr column as a gas stream, together with the unconverted methane and other light gases. The products are then separated and recovered from the methane and light gases using any of a number of techniques. Nonlimiting examples include distillation, pressure swing adsorption, and membrane separation technologies.
In some embodiments, the product clean-up unit comprises or includes a reactor for converting halogenated hydrocarbons present in the product stream into unhalogenated hydrocarbons. For example, under certain conditions, small amounts of C1-C4 bromoalkanes, bromobenzene, and/or other brominated species are formed and pass from the coupling reactor to the liquid-liquid splitter 16 and then to the product clean-up unit 17 . These brominated species can be “hydrodehalogenated” in a suitable reactor. In one embodiment, such a reactor comprises a continuous fixed bed, catalytic converter packed with a supported metal or metal oxide catalyst. Nonlimiting examples of the active component include copper, copper oxide, palladium, and platinum, with palladium being preferred. Nonlimiting examples of support materials include active carbon, alumina, silica, and zeolites, with alumina being preferred. The reactor is operated at a pressure of 0-150 psi, preferably 0-5 psi, and a temperature of 250-400° C., preferably 300-350° C., with a GHSV of 1200-60 hr −1 , preferably about 240 hr −1 . When bromobenzene (e.g.) is passed over such a reactor, it is readily converted to benzene and HBr, with some light hydrocarbons (e.g., C3-C7) produced as byproducts. Although carbon deposition (coking) can deactivate the catalyst, the catalyst can be regenerated by exposure to oxygen and then hydrogen at, e.g., 500° C. and 400° C., respectively.
After HBr is separated from the hydrocarbon products, the unconverted methane leaves with the light gases in the vapor outlet of the HBr absorption unit. In one embodiment of the invention, unconverted methane is separated from the light gases in a separation unit (“SEP II” in the FIGS.), which operates using pressure or temperature swing adsorption, membrane-based separation, cryogenic distillation (preferable for large-scale production), or some other suitable separation process. Low methane conversions in the bromination reactor may result in the coupling products being carried with the light gases, which in turn would necessitate the recovery of these species from the lights gases. Separation technologies that can be employed for this purpose include, but are not limited to, distillation, pressure or temperature swing adsorption, and membrane-based technologies.
In another aspect of the invention, a process for separating anhydrous HBr from an aqueous solution of HBr is provided. HBr forms a high-boiling azeotrope with water; therefore, separation of HBr from the aqueous solution requires either breaking the azeotrope using an extractive agent or bypassing the azeotrope using pressure swing distillation. FIG. 5 illustrates one embodiment of an extractive distillation unit for separating HBr from water. Water is extracted in a distillation column 200 and HBr is obtained as the distillate stream 201 . The distillate stream may also contain small amounts of water. In one embodiment, the distillation column 200 is a tray-tower or a packed column. Conventional ceramic packing is preferred over structured packing Aqueous bromide salt, such as CaBr 2 , is added at the top of the distillation column, resulting in the extraction of water from aqueous HBr. A condenser may not be required for the column. A reboiler 203 is used to maintain the vapor flow in the distillation column. The diluted stream of aqueous CaBr 2 202 is sent to the evaporation section 206 , which, optionally has a trayed or packed section. The bottoms stream from the column is heated before entering the evaporation section. Stream 207 comprising mostly water (and no more than traces of HBr) leaves the evaporation section.
In one embodiment, HBr is displaced as a gas from its aqueous solution in the presence of an electrolyte that shares a common ion (Br − or H + ) or an ion (e.g. Ca 2+ or SO 4 2− ) that has a higher hydration energy than HBr. The presence of the electrolyte pushes the equilibrium HBr aq ⇄HBr gas towards gas evolution, which is further facilitated by heating the solution.
Aqueous solutions of metal bromides such as CaBr 2 , MgBr 2 also KBr, NaBr, LiBr, RbBr, CsBr, SrBr 2 , BaBr 2 , MnBr 2 , FeBr 2 , FeBr 3 , CoBr 2 , NiBr 2 , CuBr 2 , ZnBr 2 , CdBr 2 , AlBr 3 , LaBr 3 , YBr 3 , and BiBr 3 can be used as extractive agents, with aqueous solutions of CaBr 2 , MgBr 2 , KBr, NaBr, LiBr or mixtures thereof being preferred. The bottoms stream of the distillation column contains a diluted solution of the extracting agent. This stream is sent to another distillation column or a vaporizer where water is evaporated and the extracting agent is concentrated before sending it back to the extractive distillation column. Sulfuric acid can be used as an extracting agent if its reaction with HBr to form bromine and sulfur dioxide can be minimized. Experiments carried out to demonstrate the separation of anhydrous HBr from an aqueous solution of HBr are described in Examples 2 and 3.
In another aspect of the invention, various approaches to product clean-up (separation and/or purification) are provided. A number of bromide species may be present in the unpurified product stream: HBr, organic bromides such as methyl bromide and dibromomethane, and bromo-aromatics. In one embodiment of the invention, hydrocarbon products are separated from brominated species by passing the product stream over copper metal, NiO, CaO, ZnO, MgO, BaO, or combinations thereof. Preferably, the products are run over one or more of the above-listed materials at a temperature of from 25-600° C., more preferably, 400-500° C. This process is tolerant of CO 2 that may be present.
In another embodiment, particularly for large-scale production of hydrocarbons, unconverted methane is separated from other light hydrocarbons as well as heavier products (e.g., benzene, toluene, etc.) using distillation. For example, in FIGS. 1 and 2 , methane and other light hydrocarbons exit the absorption column through a gas outlet and are directed to a separation unit (SEP. II). Any unconverted methyl bromide will be removed with the light gases and can be recycled back to the bromination/reproportionation reactor. Heavier hydrocarbons are removed as a liquid distillate.
Molecular Halogen Generation
In one embodiment of the invention, catalytic halogen generation is carried out by reacting hydrohalic acid and molecular oxygen over a suitable catalyst. The general reaction can be represented by equation (1):
The process occurs at a range of temperatures and mole ratios of hydrohalic acid (HX) and molecular oxygen (O 2 ), i.e., 4:1 to 0.001:1 HX/O 2 , preferably 4:1 (to fit the reaction stoichiometry), more preferably 3.5:1 (to prevent eventual HBr breatkthrough).
Halogen can be generated using pure oxygen, air, or oxygen-enriched gas, and the reaction can be run with a variety of inert nonreacting gases such as nitrogen, carbon dioxide, argon, helium, and water steam being present. Any proportion of these gases can be combined as pure gases or selected mixtures thereof, to accommodate process requirements.
A number of materials have been identified as halogen generation catalysts. It is possible to use one type of catalyst or a combination of any number, configuration, or proportion of catalysts. Oxides, halides, and/or oxy-halides of one or more metals, such as Cu, Ag, Au, Fe, Co, Ni, Mn, Ce, V, Nb, Mo, Pd, Ta, or W are representative, more preferably Mg, Ca, Sr, Ba, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, or Ce. The most preferable catalysts are oxides, halides, and/or oxy-halides of Cu.
Although not bound by theory, the following equations are considered representative of the chemistry believed to take place when such materials are used to catalyze halogen formation:
CaO+2HBr→CaBr 2 +H 2 O (2)
CaBr 2 +½O 2 →CaO+Br 2 (3)
for metal oxides in which the metal does not change oxidation states, and
Co 3 O 4 +8HBr→3CoBr 2 +4H 2 O+Br 2 (4)
3CoBr 2 +2O 2 →Co 3 O 4 +3Br 2 (5)
for metal oxides in which the metal does change oxidation states. The net reaction for (2)+(3) and (4)+(5) is (7):
which is equivalent to (1).
In one embodiment of the invention, chlorine is used as the halogenating agent, and ceria (CeO 2 ) is used to catalyze the generation of chlorine from hydrochloric acid. The following equations are considered representative:
CeO 2 +4HCl→CeCl 2 +H 2 O+Cl 2 (8)
CeCl 2 +O 2 →CeO 2 +Cl 2 (9)
for an overall reaction: 2HCl+½O 2 →H 2 O+Cl 2 (10)
which is also equivalent to (1).
This use of ceria is quite novel, as it allows essentially complete consumption of HCl. In contrast, previous reactions of metal oxides, HCl, and oxygen have typically yielded HCl/Cl 2 mixtures. Thus, ceria can advantageously be employed as a halogen regeneration catalyst, particularly where chlorine is used for alkane halogenation, with chlorine's attendant lower cost and familiarity to industry.
In one embodiment of the invention, the halogen generation catalyst(s) are supported on porous or nonporous alumina, silica, zirconia, titania or mixtures thereof, or another suitable support. A range of temperatures can be employed to maximize process efficiency, e.g., 200-600° C., more preferably 350-450° C.
Recovery and Recycle of Molecular Halogen
Halogen generation produces both water and molecular halogen. Water can be separated from halogen and removed before the halogen is reacted with the hydrocarbon feedstock. Where the halogen is bromine, a bromine-water, liquid-liquid phase split is achieved upon condensation of a mixture of these species. For example, in one embodiment of the invention, a liquid-liquid flash unit is used to separate most of the bromine from water, simply and inexpensively. The bromine phase typically contains a very small amount of water, and can be sent directly to the bromination reactor. The water phase, however, contains 1-3 wt % bromine. However, if air is used in the bromine generation step, nitrogen and unconverted oxygen are present with the bromine and water stream that enters the flash.
The gas leaving the flash unit primarily consists of nitrogen and unconverted oxygen, but carries with it some bromine and water. The amount of bromine leaving with the vapor phase depends on the temperature and pressure of the flash. The flash can be operated at temperatures ranging from 0 to 50° C.; however, a lower temperature (ca 2 to 10° C.) is preferred to reduce bromine leaving in the vapor stream. The vapor stream is sent to the bromine scavenging section for bromine recovery. In one embodiment, the operating pressure is 1 to 50 bar, more preferably 1 to 30 bar. Since water freezes at 0° C., it is not possible to substantially reduce the temperature of the flash 19 . However, the vapor stream from the flash can be contacted with a chilled brine solution, at temperatures from −30° C. to 10° C. Chilled brine temperatures lower than that of the flash can substantially reduce the bromine scavenging requirement of the scavenging unit. Vaporizing the bromine by heating the brine can then occur, with further heating employed to facilitate concentration of the brine for re-use. This approach to bromine recovery can be carried out either continuously or in batch mode.
Bromine contained in the water-rich phase leaving the liquid-liquid flash can be effectively recovered by distillation. Other means, such as using an inert gas to strip the bromine from the water phase (described by Waycuilis) and adsorption-based methods, are not very effective, and potentially can result in a significant loss of bromine. The presently described distillation subprocess produces bromine or bromine-water azeotrope as a distillate, which is recycled back to the flash unit. Water is contained in the bottoms stream. Bromine can react reversibly with water to form small amounts of HBr and HOBr. In the distillation scheme, therefore, ppm levels of HBr (and/or HOBr) can be present in the bottoms stream. A side-stream rectifier or stripper can be utilized to reduce the bromine content of the bottoms stream to produce a pure water stream. Other alternatives that can reduce the bromine content of the water to below 10 ppm range include, but are not limited to, the addition of acids such as sulfuric acid, hydrochloric acid, and phosphoric acid, in very small quantities to reduce the pH of the water stream. Lowering the pH drives the HBr and HOBr stream back to bromine and water, thereby substantially reducing the loss of bromine in the water stream. HBr present in the water stream can also be recovered using ion-exchange resins or electrochemical means.
Recovery of All Halogen for Reuse
For both economic and environmental reasons, it is preferred to minimize, if not completely eliminate, loss of halogen utilized in the overall process. Molecular bromine has the potential to leave with vented nitrogen and unconverted oxygen if it is not captured after Br 2 generation. Bromine scavenging can be carried out in a bed containing solid CuBr or MnBr 2 , either loaded on a support or used in powder form, to capture Br 2 from a gas stream that may also contain H 2 O, CO 2 , O 2 , methane &/or N 2 . In one embodiment of the invention, bromine scavenging is performed within a range of temperatures, i.e., from −10° C. to 200° C. When bromine scavenging is complete, molecular bromine can be released from the bed by raising the temperature of the bed to 220° C. or higher, preferably above 275° C. It is important that there be little if any O 2 in the bed during bromine release, as O 2 will oxidize the metal and, over time, reduce the bromine-scavenging capacity of the bed.
Construction of Critical Process Elements with Unique Corrosion-Resistant Materials
Corrosion induced by any halogen-containing process, whether in the condensed phase or the vapor phase, presents a significant challenge in the selection of durable materials for the construction of reactors, piping, and ancillary equipment. Ceramics, such as alumina, zirconia, and silicon carbides, offer exceptional corrosion resistance to most conditions encountered in the process described herein. However, ceramics suffer from a number of disadvantages, including lack of structural strength under tensile strain, difficulty in completely containing gas phase reactions (due to diffusion or mass transport along jointing surfaces), and possibly undesirable thermal transport characteristics inherent to most ceramic materials. Constructing durable, gas-tight, and corrosion resistant process control equipment (i.e. shell and tube type heat-exchangers, valves, pumps, etc.), for operation at elevated temperatures and pressures, and over extended periods of time, will likely require the use of formable metals such as Au, Co, Cr, Fe, Nb, Ni, Pt, Ta, Ti, and/or Zr, or alloys of these base metals containing elements such as Al, B, C, Co, Cr, Cu, Fe, H, Ha, La, Mn, Mo, N, Nb, Ni, O, P, Pd, S, Si, Sn, Ta, Ti, V, W, Y, and/or Zr.
According to one embodiment of the invention, the process and subprocesses described herein are carried out in reactors, piping, and ancillary equipment that are both strong enough and sufficiently corrosion-resistant to allow long-term continued operation. Selection of appropriate materials of construction depends strongly on the temperature and environment of exposure for each process control component.
Suitable materials for components exposed to cyclic conditions (e.g. oxidizing and reducing), as compared to single conditions (oxidizing or reducing), will differ greatly. Nonlimiting examples of materials identified as suitable for exposure to cyclic conditions, operating in the temperature range of from 150-550° C., include Au and alloys of Ti and Ni, with the most suitable being Al/V alloyed Ti (more specifically Ti Grd-5) and Ni—Cr—Mo alloys with high Cr, low Fe, and low C content (more specifically ALLCOR®, Alloy 59, C-22, 625, and HX). Nonlimiting examples of materials identified as suitable for exposure to either acid halide to air, or molecular halogen to air cyclic conditions, in the temperature range 150-550° C., either acid halide to air, or molecular halogen to air include alloys of Fe and Ni, with the most suitable being alloys of the Ni—Cr—Mo, and Ni—Mo families. Nonlimiting examples of materials identified as suitable for single environment conditions, in the temperature range 100° C.-550° C., include Ta, Au, and alloys of Fe, Co, and Ni. For lower temperature conditions (<280° C.), suitable polymer linings can be utilized such as PTFE, FEP, and more suitably PVDF. All materials may be used independently or in conjunction with a support material such as coating, cladding, or chemical/physical deposition on a suitable low-cost material such as low-alloy steels.
FIG. 6 schematically illustrates an alternate mode of operation for a continuous process for converting methane, natural gas, or other alkane feedstocks into higher hydrocarbons. Alkanes are brominated in the bromination section in the presence of water formed during bromine generation, including recycled water. The bromination products pass either through a reproportionation reactor or through the reproportionation section of the bromination reactor, where the light gases are reproportionated to form olefins and alkyl bromides by using the polybromides as brominating agents. The reproportionation products, which include olefins, alkyl monobromides, some polybromides, and HBr, along with any unreacted alkanes, are then sent to the coupling reactor. The coupling products are sent to a vapor-liquid-liquid flash. Higher hydrocarbon products are removed as an organic phase from the vapor-liquid-liquid flash, while aqueous HBr is removed as the heavier phase. The gas stream from the flash is sent to a separation system to recover methane and light gases, which are recycled back to the bromination and reproportionation sections, respectively.
Nitrogen must be removed from the gas recycle stream if air is used as an oxidant in bromine generation. The aqueous HBr stream coming out of the vapor-liquid-liquid flash is sent to the HBr/water separation system, where water is recovered. The separation can be carried out in a distillation column, where pure water is taken out as a distillate and the bottoms stream is an aqueous solution of HBr (having a higher concentration of HBr than the feed to the distillation column). The aqueous HBr stream is sent back to the bromine generation section, where bromine is generated from aqueous HBr in the presence of air or oxygen.
Alternatively, extractive distillation is used to separate HBr from water. The separated HBr is sent to the bromine generation reactor and bromine is generated from aqueous HBr in the presence of air or oxygen. Complete conversion of HBr is not necessary in the bromine generation reactor. Periodic decoking can be carried out for the bromination, reproportionation, and/or coupling reactors, with the bromine-containing decoking product stream being routed to the bromine generation reactor.
Another continuous process alternative is shown in FIG. 7 . Alkanes are brominated in the bromination section in the presence of water formed during bromine generation, including recycled water. The bromination products (which include monobromides and polybromides) pass through either a reproportionation reactor or the reproportionation section of the bromination reactor, where the light gases are reproportionated to form alkyl bromides, using the polybromides as brominating agents. The reproportionation products—alkyl monobromides, olefins, a small amount of polybromides, and HBr—and any unreacted alkanes are then sent to a separation unit where aqueous HBr is separated from the alkyl bromides. Monobromides in the alkyl bromide stream are separated from the polybromides. The polybromides are recycled to the reproportionation section where polybromides react with the recycle gases to form olefins and monobromides.
The aqueous HBr separation from the alkyl bromides can be carried out in a distillation column coupled with a liquid-liquid flash. The alkyl bromide stream can contain HBr. The monobromides are fed into the coupling section, and the products are sent to a water absorption column where HBr produced in the coupling reactor is removed from the products and unconverted gas. The liquid outlet of the absorption column is fed to a vapor-liquid-liquid flash separation unit, where higher hydrocarbon products are removed as an organic phase and aqueous HBr is removed as the heavier phase. The gas outlet from the absorption column is sent to a separation system to separate methane from the light gases. The recovered methane is recycled back to the bromination section, while the light gases are recycled to the reproportionation section.
Nitrogen must be separated before the gases are recycled if air is used as an oxidant in bromine generation. The aqueous HBr stream from the vapor-liquid-liquid flash is combined with the aqueous HBr stream from the alkyl bromide separation section and sent to the HBr/Water separation system. The separation can be carried out in a distillation column, where pure water is taken out as a distillate and the bottoms stream is an aqueous solution of HBr having a higher concentration of HBr compared with the feed to the distillation column. The aqueous HBr stream is sent back to the bromine generation section, where bromine is generated from aqueous HBr in the presence of air, oxygen or enriched air.
Alternatively, extractive distillation is used to separate HBr from water. The separated HBr is sent to the bromine generation reactor, where bromine is generated from aqueous HBr in the presence of air, oxygen, or enriched air. Complete conversion of HBr to bromine is not required during bromine generation. Periodic decoking of the bromination, reproportionation and coupling reactors can be carried out, with the bromine-containing decoking product stream being routed to the bromine generation reactor.
To facilitate a better understanding of the present invention, the following examples of certain aspects of some embodiments are given. In no way should the following examples be read to limit, or define, the scope of the invention.
EXAMPLE 1
Reproportionation of Dibromomethane with Propane
Methane (11 sccm, 1 atm) was combined with nitrogen (15 sccm, 1 atm) at room temperature via a mixing tee and passed through a room temperature bubbler full of bromine. The CH 4 /N 2 /Br 2 mixture was plumbed into a preheated glass tube at 500° C., and bromination of the methane took place with a residence time (“t res ”) of 60 seconds, producing primarily bromomethane, dibromomethane, and HBr. The stream of nitrogen, HBr, and partially brominated hydrocarbon was combined with propane (0.75 sccm, 1 atm) in a mixing tee and passed into a second glass reactor tube at 525° C. with a residence time (“t res ”) of 60 s. In the second reactor tube, polybrominated hydrocarbons (i.e. CH 2 Br 2 , CHBr 3 ) react with the propane to produce bromopropanes. The reproportionation is idealized by the following reaction:
CH 2 Br 2 +C 3 H 8 →CH 3 Br+C 3 H 7 Br
As products left the second reactor, they were collected by a series of traps containing 4 M NaOH (which neutralized the HBr) and hexadecane (containing octadecane as an internal standard) to dissolve as much of the hydrocarbon products as possible. Volatile components like methane and propane were collected in a gas bag after the HBr/hydrocarbon traps. All products were quantified by gas chromatography. The results (“Ex. 1”) are summarized in Table 1. For comparison, the reactions were also run with two reactors, but without reproportionation with propane (“Control A”), and with only the first reactor and without propane (“Control B”).
TABLE 1
Reproportionation of Dibromomethane
Ex. 1 (bromi-
Control
Control
nation/repro-
A (bromi-
B (bromi-
portionation)
nation)
nation)
Bromination t res
60
60
60
Reproportionation t res
60
60
0
CH 4 conversion
40%
47%
45%
CH 3 Br/(CH 3 Br + CH 2 Br 2 )
93%
84%
74%
C 3 H 8 conversion
85%
N/A
N/A
Carbon balance
96%
97%
96%
EXAMPLE 2
Separation of Anhydrous HBr
20 ml stock HBr aqueous solution were added to 20 g CaBr 2 H 2 O followed by heating to 70° C. A significant evolution of HBr gas was observed (determined by AgNO 3 precipitation and the NH 3 fuming test). The released HBr was not quantified as the reaction was carried out in an open vessel.
EXAMPLE 3
Separation of Anhydrous HBr
Dehydration with H 2 SO 4 was attempted by adding a conc. solution of H 2 SO 4 to HBr. Qualitative tests were conducted in which different concentration of H 2 SO 4 were added to HBr for determination of the threshold concentration where oxidation of HBr no longer occurs:
2HBr+H 2 SO 4 →Br 2 +SO 2 +2H 2 O
It was determined that the H 2 SO 4 concentration below which no oxidation is apparent is about 70 wt. %. 30 ml 70% H 2 SO 4 was added to 30 ml stock HBr azeotrope (48 wt. %) and the mixture was heated to boiling. The HBr content was determined quantitatively by AgNO 3 precipitation and gravimetric determination of AgBr from a solution aliquot at the moment of mixing, after 15 min and after 30 min. boiling.
EXAMPLE 4
Metathesis of Brominated Methane Over Selected Catalysts
A series of experiments were conducted in which methane was brominated in a manner substantially the same as or similar to that described in Example 1 (10 sccm methane bubbled through room temperature bromine, followed by passage of the mixture through a reactor tube heated to 500° C.), and the bromination products were then passed over various metal-ion exchanged or impregnated zeolite catalysts, at atmospheric pressure (total pressure), at a temperature of from 350 to 450° C., with a residence time of 40 seconds. Table 2 summarizes the distribution of metathesis products. Catalysts are denoted by metal ion (e.g., Ba, Co, Mn, etc.) and by type of Zeolyst Int'l. zeolite (e.g., 5524, 58, 8014, etc.). The mass (mg) of each product, as well as the total mass of products is given for each run. The abbreviations, B, PhBr, T, X, and M refer to benzene, phenyl bromide, toluene, xylene, and mesitylene, respectively.
TABLE 2
Metathesis of Brominated Methane Over Selected Catalysts
Total
T (C.)
Catalyst
B
PhBr
T
X
M
(mg)
350
Ba 5524
0.25
0
0.96
2.58
3.14
6.93
350
Ba 58
0.31
0
1.48
3.2
3.11
8.11
350
Ba 8014
0.3
0
1.3
2.87
3.15
7.6
350
Ca 58
0.2
0
0.81
2.44
3.09
6.53
350
Co 2314
1.22
0.02
3.05
2.18
0.56
7.04
350
Co 3024
0.36
0
2.06
4.21
3.47
10.1
350
Co 58
0.2
0
1.05
2.91
3.34
7.5
350
Mg 3024
0.31
0
1.53
3.59
3.89
9.32
350
Mg 58
0.28
0
1.41
3.3
3.43
8.42
350
Mn 2314
1.07
0.03
2.86
2.26
0.65
6.86
350
Mn 3024
0.53
0
2.92
4.8
3.02
11.27
350
Mn 58
0.17
0
0.88
2.7
3.62
7.37
350
Ni 2314
1.12
0.05
2.94
2.44
0.74
7.29
350
Ni 3024
0.61
0
2.82
3.85
2.13
9.41
375
Ba 5524
0.32
0
1.32
2.82
2.57
7.04
375
Ba 58
0.4
0
1.84
2.93
2.4
7.57
375
Ba 8014
0.32
0
1.23
2.84
2.95
7.34
375
Ca 58
0.2
0
0.96
2.55
2.93
6.64
375
Co 3024
0.47
0
2.3
3.52
2.18
8.48
375
Co 58
0.3
0
1.54
2.83
2.42
7.1
375
Mg 3024
0.37
0
1.81
3.26
2.78
8.22
375
Mg 58
0.34
0
1.67
3.04
2.74
7.8
375
Mn 3024
0.62
0
2.91
3.9
2.17
9.59
375
Mn 58
0.22
0
1.18
2.71
2.83
6.94
375
Pd 2314
1.54
0
3.1
1.83
0.37
6.85
400
Ba 5524
0.46
0
2.37
4.16
2.95
9.94
400
Ba 58
0.7
0
3.15
3.91
2.7
10.47
400
Ba 8014
0.38
0
1.57
3.81
3.77
9.53
400
Ca 58
0.41
0
1.89
3.43
2.81
8.54
400
Co 3024
0.78
0
3.42
4.14
2.26
10.6
400
Co 58
0.62
0
2.71
3.36
2.31
8.99
400
Mg 3024
0.76
0
3.26
4.11
2.64
10.76
400
Mg 58
0.71
0
3.04
3.74
2.59
10.08
400
Mn 3024
0.98
0
4.1
4.38
2.06
11.52
400
Mn 58
0.48
0
2.26
3.44
2.64
8.82
400
Ni 3024
0.81
0
3.15
3.35
1.72
9.04
400
Pb 2314
1.2
0.03
3.25
3.27
1.2
8.94
400
Pb 3024
1.07
0.04
2.77
3.63
1.66
9.17
400
Pd 2314
2.44
0
3.16
1.22
0.18
7.01
400
Sr 2314
2.13
0.01
4.05
2.29
0.46
8.94
400
Sr 3024
1.93
0.05
4.03
2.67
0.65
9.32
425
Ag 3024
2.79
0.02
4.16
1.78
0.29
9.04
425
Ag 8014
3.09
0.02
3.52
1.09
0.16
7.88
425
Ba 5524
0.54
0
2.67
3.67
2.33
9.22
425
Ba 58
0.79
0
3
2.94
1.75
8.48
425
Bi 2314
3.13
0.03
4.47
1.61
0.23
9.48
425
Co 2314
3.39
0.03
4.34
1.59
0.25
9.6
425
Co 3024
1.07
0
3.42
2.79
1.09
8.38
425
Cu 2314
2.89
0.02
4.74
2.13
0.37
10.15
425
Li 5524
1.51
0.04
3.31
3.27
1.12
9.24
425
Mg 3024
0.99
0
3.28
2.85
1.37
8.48
425
Mg 58
0.81
0
2.62
2.16
1.11
6.7
425
Mn 3024
1.22
0
3.9
3.01
1.14
9.27
425
Mo 2314
3.06
0.04
4.02
1.46
0.24
8.82
425
Ni 3024
0.97
0
3.38
2.85
1.32
8.51
425
Sr 3024
2.53
0.02
4.36
2.22
0.43
9.56
450
Ag 3024
3.84
0.02
4.27
1.36
0.18
9.67
450
Bi 2314
3.9
0.01
3.59
0.67
0.06
8.23
450
Ca 2314
3.64
0.02
4.1
1
0.16
8.92
450
Co 2314
4.12
0.01
3.77
0.77
0.08
8.75
450
Cu 2314
3.65
0
4.3
1.1
0.14
9.19
450
Fe 2314
4.42
0.02
3.43
0.74
0.09
8.69
450
Fe 3024
3.61
0.01
2.96
0.63
0.08
7.28
450
Fe 5524
3.99
0.03
3.63
0.85
0.11
8.6
450
La 2314
3.48
0.01
3.81
0.87
0.12
8.29
450
Li 8014
1.74
0.02
2.61
2.67
0.84
7.89
450
Mg 2314
4.2
0.02
3.84
0.76
0.1
8.92
450
Mn 2314
3.78
0.02
3.9
0.88
0.12
8.7
450
Mo 2314
3.88
0.01
3.26
0.58
0.06
7.79
450
Ni 2314
4.39
0.01
3.12
0.44
0.03
8
450
Pb 2314
2.58
0.01
4.68
2.31
0.45
10.02
450
Pb 3024
2.08
0.01
4.44
2.87
0.7
10.1
450
Pb 5524
1.89
0.02
3.58
2.71
0.73
8.93
450
Pd 2314
4.03
0
1.58
0.14
0
5.76
450
Sr 2314
3.71
0
4.78
1.68
0.21
10.39
450
Sr 3024
2.51
0.01
3.76
1.61
0.26
8.14
EXAMPLE 5
Hydrodehalogenation of Bromobenzene, and Catalyst Regeneration
A test solution (1.5 ml/hr), which includes 1.9 wt % bromobenzene (PhBr) dissolved in dodecane, diluted by N 2 (1.1 ml/min) was fed into a tubular quartz reactor in which 3.6 g of highly dispersed precious metal catalyst (Pd/Al 2 O 3 , 0.5 wt %) was loaded. The reaction was carried out at 325° C. with a residence time of 15 s. The reaction effluent was trapped in a bubbler with 8 ml 4M NaOH solution pre-added. The carrier gas as well as the gaseous product were collected in a gas bag. All of the carbon-based products in the gas phase and oil phase in the liquid product were subjected to GC analysis. For the base trap solution, the HBr concentration was measured with an ion-selective electrode. Based on all of these measurements, carbon and bromine balances were calculated.
The experiment was continuously run for over 300 hours until the conversion of PhBr dropped from 100% in the initial 70 hrs to below 30% ( FIG. 8 ). Hydrodebromination of PhBr took place over the catalyst bed with the formation of benzene (“BZ”) and HBr as the major products, accompanied with some light hydrocarbons (C 3 -C 7 ) being detected as byproducts, which originated from solvent decomposition. Carbon deposition was recognized as the primary reason for deactivation of the catalyst. The catalyst proved to be re-generable via decoking at 500° C. with O 2 oxidation (5 ml/min) for 10 hrs, followed by H 2 reduction (20 ml/min) at 400° C. for 3 hrs. The regenerated catalyst was identified to be as effective as the fresh catalyst, as confirmed by its ability to catalyze the same hydrodebromination reaction without activity loss in the first 70 hours ( FIG. 9 ).
The invention has been described with references to various examples and preferred embodiments, but is not limited thereto. Other modifications and equivalent arrangements, apparent to a skilled person upon consideration of this disclosure, are also included within the scope of the invention. For example, in an alternate embodiment of the invention, the products 25 from the bromine generation reactor are fed directly into the bromination reactor 3 . The advantage of such a configuration is in eliminating the bromine holdup needed in the flash unit 27 , thereby reducing the handling of liquid bromine. Also, by eliminating the bromine scavenging section including units 26 , 27 , 31 and 34 , the capital cost for the process can be reduced significantly. For energy efficiency, it is desirable to have the outlet of bromine generation be equal to the bromination temperature. For bromine generation, cerium-based catalysts are therefore preferred over copper-based catalysts in this embodiment, since cerium bromide has a higher melting point (722° C.) than copper (I) bromide (504° C.). The presence of oxygen in bromination and coupling reduces the selectivity to the desired products; therefore, the bromine generation reactor must consume all of the oxygen in the feed. In this embodiment, the monobromide separation 5 must be modified to remove water using a liquid-liquid split on the bottoms stream of the distillation column 51 . The water removed in the liquid-liquid split contains HBr, which can be removed from water using extractive distillation (see, e.g., FIG. 5 ), and then recycled back to the bromine generation section.
Therefore, the present invention is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the present invention. While compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of” or “consist of” the various components and steps. All numbers and ranges disclosed above may vary by some amount. Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an”, as used in the claims, are defined herein to mean one or more than one of the element that it introduces. If there is any conflict in the usages of a word or term in this specification and one or more patent or other documents that may be incorporated herein by reference, the definitions that are consistent with this specification should be adopted. | A method comprising providing a halogen stream; providing a first alkane stream; reacting at least a portion of the halogen stream with at least a portion of the first alkane stream to form a halogenated stream, wherein the halogenated stream comprises alkyl monohalides, alkyl polyhalides, and a hydrogen halide; providing a second alkane stream; and reacting at least a portion of the second alkane stream with at least a portion of the alkyl polyhalides to create at least some additional alkyl monohalides. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No. 15/044,190, filed Feb. 16, 2016, which is a continuation of application Ser. No. 14/061,820, filed Oct. 24, 2013, now U.S. Pat. No. 9,290,303. The aforementioned applications and patent are hereby incorporated by reference into this disclosure.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to improvements for thermoplastic films, particularly thermoplastic films used in the manufacture of bags including trash bags. In particular, the present invention relates to improvements to trash bags and embossed patterns for such bags.
[0004] 2. Description of the Related Art
[0005] Thermoplastic films are used in a variety of applications. For example, thermoplastic films are used in sheet form for applications such as drop cloths, vapor barriers, and protective covers. Thermoplastic films can also be converted into plastic bags, which may be used in a myriad of applications. The present invention is particularly useful to trash bags constructed from thermoplastic film, but the concept and ideas described herein may be applied to other types of thermoplastic films and bags as well.
[0006] Depending on the application, the use of thermoplastic film presents technical challenges due to the fact that thermoplastic film is inherently soft and flexible. Specifically, all thermoplastic films are susceptible to puncture and tear propagation. In some instances, it may be possible to increase the thickness of the film or select better polymers to enhance the physical properties of the film. However, these measures increase both the weight and cost of the thermoplastic film and may not be practicable. In light of the technical challenges of thermoplastic film, techniques and solutions have been developed to address the need for improved shock absorption to reduce the likelihood of puncture. For example, it is known to impart stretched areas into thermoplastic films as a means of inducing shock absorption properties into the film.
[0007] U.S. Pat. No. 5,205,650, issued to Rasmussen and entitled Tubular Bag with Shock Absorber Band Tube for Making Such Bag, and Method for its Production , discloses using thermoplastic film material with stretchable zones wherein the film material has been stretched in a particular direction with adjacent unstretched zones that extend in substantially the same direction. The combination of the stretched zones and adjacent unstretched zones provides a shock absorber band intended to absorb energy when the bag is dropped. Specifically, when a bag is dropped or moved, the contents inside the bag exert additional forces that would otherwise puncture or penetrate the thermoplastic film. However, the shock absorber bands absorb some of the energy and may prevent puncture of the film.
[0008] Another example of a thermoplastic film material designed to resist puncture is disclosed in U.S. Pat. No. 5,518,801, issued to Chappell and entitled Web Materials Exhibiting Elastic - Like Behavior . Chappell, in the aforementioned patent and other related patents, discloses using a plurality of ribs to provide stretchable areas in the film much like Rasmussen. Chappell also discloses methods of manufacturing such thermoplastic film with such ribs.
[0009] Another example of shock absorption to prevent puncture is disclosed in U.S. Pat. No. 5,650,214 issued to Anderson and entitled Web Materials Exhibiting Elastic - Like Behavior and Soft Cloth - Like Texture . Anderson discloses using a plurality of embossed ribs defining diamond-shaped areas with a network of unembossed material between the diamond-shaped areas. Thus, the unembossed area comprises a network of straight, linear unembossed material extending in two perpendicular directions.
[0010] The foregoing specifically address the desire to increase the shock absorption of the thermoplastic film to reduce the likelihood of punctures occurring in the film. However, none of the foregoing solutions address the problem of reducing tear propagation in a thermoplastic bag.
[0011] Previously known solutions to limiting tear propagation are based on two primary concepts. First, longer and more tortuous tear paths consume more energy as the tear propagates and can help in limiting the impact of the tear in a bag or thermoplastic film. Second, many thermoplastic films, particularly thermoplastic films made using a blown-film extrusion process, have different physical properties along different axes of the film. Consequently, certain prior art solutions take advantage of the differential properties of thermoplastic films by redirecting tears into a different direction which offers greater resistance to the propagating tear. For example, some solutions redirect a tear propagating in the weaker machine direction of blown film into the stronger cross-direction.
[0012] One solution for reducing tear propagation s based on the idea that longer, tortuous tear paths are preferable and is described in U.S. Pat. No. 6,824,856, issued to Jones and entitled Protective Packaging Sheet . Jones discloses materials suitable for packaging heavy loads by providing an embossed packaging sheet with improved mechanical properties. Specifically, a protective packaging sheet is disclosed where surfaces of the sheet material are provided with protuberances disposed therein with gaps between protuberances. The protuberances are arranged such that straight lines necessarily intersect one or more of the protuberances. The resulting protective packaging sheet provides mechanical properties where tears propagating across the thermoplastic sheet are subject to a tortuous path. The tortuous path is longer, and more complex, than a straight-line tear, and a tear propagating along such a path would require markedly more energy for continued propagation across the film compared to a tear along a similar non-tortuous path in the same direction. Thus, due to the increased energy required for tear propagation, the tortuous path ultimately reduces the impact of any tears that do propagate across the film.
[0013] Another example of a tear resistant plastic film is disclosed in U.S. Pat. No. 8,357,440, issued to Hall and entitled Apparatus and Method for Enhanced Tear Resistance Plastic Sheets . Hall discloses an alternative tortuous path solution and further relies on the fact that certain polymer films, particularly thermoplastic films made in a blown-film extrusion process, are known to have a stronger resistance to tear in the cross direction (also known as the transverse direction) when compared to the machine direction (i.e. the direction in which the film is extruded). The cross direction (or transverse direction) is perpendicular to the machine direction and extends around the circumference of a blown-film tube or across the width of a flattened film.
[0014] Hall discloses a solution that contemplates using preferably shaped embosses, particularly convex shaped embosses with a curved outer boundary, to provide maximum resistance to tear propagation. In most thermoplastic films, a tear will have a tendency to propagate along the path of least resistance or in the machine direction. Hall contemplates redirecting propagating tears in a tortuous path with the additional intent of redirecting the machine direction tears along the curved edges of the embossed regions and into a cross direction orientation. The redirected tears in the cross direction will be subject to additional resistance and, preferably, will propagate to a lesser degree than a tear propagating in the machine direction in an unembossed film.
[0015] Unlike the references described earlier, Jones and Hall are primarily focused on resistance to tear propagation after a puncture has occurred rather than attempting to prevent the puncture from occurring in the first place. It would be desirable to balance both of these properties, shock absorption and tortuous tear paths in the cross direction, into a single, practicable thermoplastic film. Specifically, it would be desirable to provide a thermoplastic film with a shock absorbing feature to prevent punctures in a film while also providing increased resistance to tear propagation. The present invention addresses these needs.
BRIEF DESCRIPTION OF THE RELATED DRAWINGS
[0016] A full and complete understanding of the present invention may be obtained by reference to the detailed description of the present invention and certain embodiments when viewed with reference to the accompanying drawings. The drawings can be briefly described as follows.
[0017] FIG. 1 provides an elevation view of a first embodiment of the present invention.
[0018] FIG. 2 provides an elevation view of a second embodiment of the present invention.
[0019] FIG. 3 provides an elevation view of a third embodiment of the present invention.
[0020] FIG. 4 provides an elevation view of a fourth embodiment of the present invention.
[0021] FIG. 5 provides an elevation view of a fifth embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The present disclosure illustrates several embodiments of the present invention. It is not intended to provide an illustration or encompass all embodiments contemplated by the present invention. In view of the disclosure of the present invention contained herein, a person having ordinary skill in the art will recognize that innumerable modifications and insubstantial changes may be incorporated or otherwise included within the present invention without diverging from the spirit of the invention. Therefore, it is understood that the present invention is not limited to those embodiments disclosed herein. The appended claims are intended to more fully and accurately encompass the invention to the fullest extent possible, but it is fully appreciated that certain limitations on the use of particular terms are not intended to conclusively limit the scope of protection.
[0023] Referring initially to FIG. 1 , a perspective view of a first embodiment of the present invention is shown. In particular, a thermoplastic film 100 is embossed with a plurality of embossed regions 110 , where each of the plurality of embossed regions 110 is separated by a continuous, unembossed arrangement 120 . Each of the embossed regions 110 comprises a plurality of parallel, linear embosses 130 . The parallel, linear embosses 130 are all arranged in a parallel fashion to facilitate expansion of the film in a particular direction. Furthermore, the parallel, linear embosses 130 extend substantially across the entire embossed region 110 .
[0024] In certain preferred embodiments of the present invention, the embossed regions 110 are provided with rounded corners, rather than sharp corners. As discussed with respect to the prior art, it is known that tears have a tendency to propagate along the edges of the embossed regions. Embossed regions with continuously curved borders, i.e. without sharp corners, encourage propagating tears to follow the edge of the embossed region. In contrast, when an embossed region is provided with sharp corners, the tear is more likely to diverge from the edge of the embossed region and will no longer be guided by the embossed region. Typically, such tears will continue propagating in the same direction which may provide less resistance along a less tortuous path.
[0025] The present invention builds on the concepts of tortuous path and redirecting tears in a direction that provides more resistance to continued propagation of the tear by preferably utilizing rounded corners on the embossed regions. Specifically, looking at the embodiment of FIG. 1 , the embossed regions 110 have generally rounded corners rather than sharp corners to facilitate redirection of tears propagating along the perimeter of said embossed region and into a more tortuous path that may offer increased tear resistance.
[0026] FIG. 2 shows a second embodiment of the present invention. In this embodiment, the thermoplastic film has a plurality of embossed regions 210 that are generally hexagonal in shape with rounded corners to facilitate tear redirection. Like the previous embodiments, the embossed regions 210 have a plurality of parallel, linear embosses 230 . Moreover, due to the hexagonal geometry, the continuous, unembossed arrangement 220 does not provide any location where a continuous, straight line can be drawn across the arrangement 220 . This is important because a tear propagating in the unembossed arrangement 220 cannot follow a continuous path in the machine direction, where the film is inherently weaker. Instead, assuming the tear follows the edges of the embossed regions 210 , the tear will follow a longer path that will be, at least partially, in the cross direction.
[0027] FIG. 3 shows a third embodiment of the present invention. In this third embodiment, the thermoplastic film has a variety of circular embossed regions 310 arranged along a series of parallel sinusoidal paths in the thermoplastic film separated by a continuous, unembossed arrangement 320 . This continuous, unembossed arrangement 320 offers unique advantages in that a continuous straight-line path is generally not possible assuming the size of the embossed regions 310 are properly sized, the amplitude of the sinusoidal path is sufficiently large, and there is sufficient frequency of the embossed regions 310 along the sinusoidal path. Thus, as a tear propagates across the film, it will necessarily intersect with one of the embossed regions 310 . Such tears will have a tendency to propagate around the edges of the embossed regions 310 and into varying directions.
[0028] In the embodiment disclosed in FIG. 3 , the embossed regions 310 are preferably arranged along a series of parallel, sinusoidal lines extending in a first direction. The peak amplitude, measured from the center of the sinusoidal wave to the peak of the sinusoidal wave is typically at least ½ of the diameter of the embossed regions 310 . In some embodiments of the present invention, the embossed regions 310 are also arranged along a sinusoidal path extending in a second direction. The second direction may by perpendicular to the first direction of the sinusoidal path.
[0029] In a preferred embodiment, the embossed regions 310 will all be substantially the same size. However, in other embodiments, the size of the embossed regions 310 may vary. For example, depending on the spacing between nearby embossed regions 310 , the size, or even the shapes, of the embossed regions may be modified to provide that the spacing between the embossed regions is more uniform.
[0030] FIG. 4 discloses a fourth embodiment of the present invention. In this depicted embodiment, the thermoplastic film has a plurality of circular embossed regions 410 much like the embodiment depicted in FIG. 3 . However, in this embodiment, some of the circular embosses are connected to form connecting embossed regions 412 to block some, or even all, of the sinusoidal paths between the circular embosses.
[0031] Looking back at FIG. 3 , it is apparent that, depending on the size of the embossed regions 412 and the amplitude of the sinusoidal path of embossed regions 412 , a tear may propagate along a sinusoidal path between the sinusoidal paths of the embossed regions 412 . Properly selecting the amplitude of the sinusoidal waves, adjusting the location of the embossed regions 412 along the sinusoidal path, and modifying the sizes of the various embossed regions may be used, individually or in combination with one another, to prevent tears from propagating along the sinusoidal paths by forcing tears to continually encounter embossed regions 412 and propagate around the perimeter of said embossed regions 412
[0032] Looking now at FIG. 5 , a fifth embodiment of the present invention is depicted wherein the embossed regions are random shapes with substantially curved edges. More importantly, it is desirable that a continuous, linear path cannot be drawn across the unembossed arrangement to prevent the propagation of tears across the thermoplastic film.
[0033] As previously noted, the specific embodiments depicted herein are not intended to limit the scope of the present invention. Indeed, it is contemplated that any number of different embodiments may be utilized without diverging from the spirit of the invention. Therefore, the appended claims are intended to more fully encompass the full scope of the present invention. | The present invention relates to a thermoplastic film having improved tear and puncture resistance. The thermoplastic has a plurality of embossed regions that are comprised of a plurality of parallel, linear embosses. The plurality of embossed regions is arranged so that a straight line cannot traverse the thermoplastic film without intersecting at least one of the plurality of embossed regions. | 1 |
BACKGROUND OF THE INVENTION
Electrically powered vehicles have a great potential for saving fuel and reducing atmospheric pollution but thus far these potentials have not been realized in practical applications because of the high power requirements and short battery life of such vehicles. Electric vehicles have been unable to operate for more than a few hours without having to have their batteries recharged and, because of their power demands, the motors have had to be kept small to minimize current drain. Accordingly, with less power available, the speed and driving range of electric vehicles have prohibited their use on highways and have made them impractical as an all-around means of transportation.
SUMMARY OF THE INVENTION
The vehicular electrical generating system of the present invention involves the use of one or more high-power output electrical alternators operatively connected to the drive train of an automobile, bus or other land vehicle. Normally, during cruise or acceleration, the electrical output of the generator is disabled so as not to produce a "load" on the engine or associated drive train of the vehicle. The application of any force to the vehicle brake pedal or engagement of the braking system operatively engages an electrical power output control device which enables the generating unit to utilize the motion of the vehicle to turn the rotor of the generating unit and produce a high-power electrical output which is directed to the vehicle batteries for recharging purposes. The "back EMF" of the generator, which partially accounts for the load felt by any generator prime mover, increases as power is delivered by the generator unit, thus materially adding to the effective braking force being applied to stop or decelerate the vehicle.
Accordingly, the primary purpose of the present invention is to provide an electric generating system for ground vehicles which will produce sufficient power to self-charge the operating batteries of an electrically powered vehicle in order that such vehicle may operate independently of external battery charging sources.
A second and fundamental object of the invention is to provide electrical power for a ground vehicle which derives its energy from the momentum of the vehicle during braking deceleration, absorbing the energy of the moving vehicle in power generation instead of heat produced by brakes.
A further object of the invention is to provide an internal source of electrical power generation in a vehicle which produces no load to a cruising or accelerating engine, but becomes a load on the vehicle drive train during braking operations to assist with the deceleration of the vehicle.
A still further object of the present invention is to provide a novel source of electrical battery charging power for conventional internal combustion engine vehicles wherein the source of electrical power may be disconnected from the engine output, thus improving gasoline milage, and utilize the momentum of the vehicle during braking deceleration to provide the energy source for the electrical power generation.
Other and further objects, features and advantages of the present invention will become apparent upon a reading of the following detailed description of a preferred and secondary embodiment of the invention, taken in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic diagram of the present invention as would be applied to an electrically powered vehicle using two parallel connected alternators whose operation is activated by the vehicle brake pedal.
FIG. 2 is a schematic diagram of the present invention as applied to an internal combustion engine vehicle with a single alternator activated by the vehicle brake pedal to provide charging power to the vehicle battery.
DETAILED DESCRIPTION
A preferred form of the system of the present invention is shown schematically in FIG. 1 as applied to an electrically powered vehicle. Two alternators 2 and 4 are connected by belt drive or similar system to the drive train of the vehicle. By "drive train," it is intended to mean that portion of the total drive train which is on the output side of the vehicle transmission, that is, directly connected to the wheels so as to be turned or driven any time the wheels are being turned. The mechanical connection of the rotor to the drive train is only diagramatically illustrated inasmuch as the mechanical connection per se is not part of the invention, it being within the state of the art. It should be noted that the connection preferably includes speed multiplying gearing or pulley arrangements to increase the rotational speed of the alternator rotors over the rotational speed of the drive shaft of the vehicle.
The alternators may be of any configuration where the output current is controlable over a range. The alternators shown in FIG. 1 are those of a type containing rotors R 1 and R 2 having poles formed by electromagnets whose excitation comes from the vehicle battery 5 connected in series through the vehicle on-off switch 7 and a set of normally open relay contacts 18 and 19. The alternators 2 and 4 include windings forming stators S 1 and S 2 whose terminals are connected to appropriate rectifiers through which is provided the D.C. output voltage B+. The alternators used in the present invention are not equipped with the normal state of the art voltage regulator system, but in place thereof, there is provided a variable resistence 9 and 11 for alternators 2 and 4, respectively.
In normal vehicle operation, the electrical output of the alternator stators is grounded through the normally closed contacts 21, 22 and 31, 32 of electromagnetic relays 12 and 13. Likewise, the rotor fields are grounded through bleed-off resistors 15 and 16, respectively. It is the object of the invention that when the brake pedal or brake system is activated, even to a very slight extent, the relays 12 and 13 are energized to pick up the relay contacts and provide field excitation for the alternators from the battery 5, through the vehicle on-off switch 7, and through the normally opened contacts 18 and 19 of relays 12 and 13 respectively. Picking up of the relays 12 and 13 also provides circuit continuity between the stator B+ outputs and the positive side of the battery 5 through the parallel connected normally open relay contacts 21, 22 and 31, 32 of the relays 12 and 13 respectively.
The coils or relays 12 and 13 are parallel connected to one terminal of a normally open switch 30. The switch 30 is mechanically connected to the brake pedal 35 and closes upon slight actuation of the brake pedal. When the switch 30 is closed, it provides circuit continuity between the relay coils directly to the positive side of the battery 5 and current flowing from the battery through the relay coils to ground energizes the coils and causes the relays 12 and 13 to pick up.
Also connected to the brake pedal by mechanical connections 41 and 42 are the wipers 34 and 35 of variable resistors 9 and 11, respectively. As the brake pedal is pushed downwardly, the resistence of the resistors 9 and 11 is decreased because of the travel of the wipers 34 and 35. As the resistence is decreased, the current output from the generators 2 and 4 respectively increases, providing full alternator output as the brake pedal is depressed to its extreme position. It is to be understood that the system herein described contemplates that the normal hydraulic brake system of the vehicle is primarily responsible for decelerating and stopping the vehicle, however the heavy current output of the alternators 2 and 4 to the battery 5 during deep brake pedal depression provides a high "back EMF" in the alternators and resulting load to the vehicle drive train so that significant braking is provided by the alternators, in addition to the braking provided by the vehicle brake system.
As the brake pedal is applied, the alternator output increases to a maximum output current and when the brake pedal is released and resistors 9 and 11 quickly increase the resistance in the rotor circuit, the output current of the alternator drops quickly.
FIG. 2 illustrates a second embodiment of the invention as applied to a vehicle equipped with a normal internal combustion engine and the customary battery, used for starting and the operation of the electrical loads, but not for powering the drive train of the vehicle, as in the first embodiment.
An alternator 51 is sized and designed for a lower output than the alternators in the electric car embodiment of FIG. 1. The normal voltage regulator is replaced with the variable resistor 55 connected in series with the rotor R51. The rotor is driven by a drive connection to the vehicle engine output. As with the preferred form, the wiper 56 of the resistor 55 is mechanically connected to the brake pedal 58 so that the further the pedal is depressed the less will be the resistance in series with the alternator rotor R51. Decreasing the resistance 55 allows the current to increase in the rotor which increases the electrical output of the stator winding S51. The pedal 58 is mechanically connected to a switch 60, electrically connected in series between the plus side of the vehicle battery 62 and the coils 64 and 66 of relays 65 and 67. Until the relays 65 and 67 are energized by depression of the pedal 58, the B+ output of the stator winding S51 is grounded through the normally closed contacts 71 and 72 of the relay 65. Similarly, the rotor is grounded through the normally closed contacts 81 of the relay 67 and a resistor 75.
Any downward movement of the pedal 58 closes the switch 60 and causes the relays 65 and 67 to be energized, providing circuit continuity from the battery 62 through ignition switch 79, normally open relay contact 81 and resistor 55 to energize the rotor R51 and produce a charging current to the battery 62 from the stator S51 through the normally open contacts 71 and 72 of the relay 65 and the current meter A.
When the alternator is put "on-line" by the energizing of the relays, the variable resistance 55 controls the output of the alternator as a function of the brake pedal position, the output increasing with deeper depression of the pedal. Downward motion of the brake pedal also activates the normal hydraulic vehicle braking system. In such an application, the electrical generating and charging system is operative only during braking operations so as to take advantage of the energy which is usually disseminated as heat in the brake system to produce electrical battery charging power. Operating economies are achieved because the alternator does not normally represent a load to the engine.
For highway driving when the brakes may be used infrequently, there is provided a special voltage comparator and switching circuit 86 which causes the relay coils 64 and 66 to be energized when the electrical system voltage drops below a predetermined level. The voltage output of the battery 62 is sensed through the normally closed contacts 87 of the relay 67 on line 88 when the ignition switch is on. The comparator 86 compares the system voltage against a fixed reference voltage established by the zener diode 91. When the battery voltage drops to 10 volts, the integrated circuit component 94 delivers a positive output voltage to line 92 which causes the comparator relay coil 93 to be deenergized. The relay 93 is normally energized by current flowing through the comparator circuit component 94 when the battery voltage is at the proper level. When the level drops, the voltage comparator circuit output 92 de-energizes the relay causing the current in line 95 to pass through the relay contacts 97 and onto line 98. The voltage on line 98 energizes the relay coils 64 and 66, causing the relays 65 and 67 to pick up. Thus, even though the brake pedal is not depressed, the alternator 51 will now deliver only a slight charge due to the fact that the full value of resistor 55 is still in series with the rotor R51. The value of the resistance 55 is not decreased until the brake pedal 58 is depressed. In this embodiment of this invention, the maximum value of resistor 55 is chosen so that some output can be obtained from the alternator when the relay coils 64 and 66 are energized, even though the brake pedal 58 is not depressed.
When relay 67 picks up, the sensing voltage is routed through the normally open side of relay contact 87 and through a voltage-dropping resistor 99 to the voltage comparator circuit 86. As soon as the charging system is activated, the battery voltage increases by a volt or more. Because of the sensitivity of the comparator circuit, this increase in voltage must not be "seen" on the sensing line and therefore the rerouting of the sensing voltage through the dropping resistor compensates for the increased voltage due to the charging action and provides the same level that would be obtained otherwise. With this circuit arrangement, the charging system is activated when the battery voltage drops to 10 volts and is deactivated when the voltage reaches 12.5 volts. As soon as the proper voltage level is reached, the comparator circuit de-energizes the relay coils 64 and 66, thereby causing the system to return to the previous brake-operated alternator control mode. Because the alternator output is so minimal during charging activated by the comparator circuit, the alternator load on the engine is negligible.
If the voltage comparator has command of the generating system at the time the brake pedal is depressed, the value of the resistor 55 will be reduced, thereby increasing the output of the alternator until the pedal is released. At that time, the voltage will again be sensed and the comparator circuit will activate the battery charging function of the system, providing the voltage is still below the desired level. | An electrical generating system for land vehicles comprising an electrical generator operatively connected to the vehicle drive train, a battery and a system interconnecting the brake pedal to a switching arrangement which connects the generator output into the battery for charging purposes upon depression of the brake pedal and also provides for increasing the generator output as a function of brake pedal depression, thus utilizing the back EMF of the generator as a load on the drive train to assist in braking the vehicle and utilizing the momentum of the vehicle during braking to furnish energy to the generator. | 8 |
FIELD OF THE INVENTION
The present invention relates to a semiconductor substrate material and to a method of fabricating the same. More specifically, the present invention relates to a strained semiconductor, e.g., Si-on-insulator (SSOI) substrate material and a robust method of fabricating the same that avoids wafer bonding.
BACKGROUND OF THE INVENTION
In the semiconductor industry, there has been an increasing interest in enhancing performance of complementary metal oxide semiconductor (CMOS) devices by replacing conventional silicon-on-insulator (SOI) substrates with strained semiconductor-on-insulator (SSOI) substrates. The reason behind this interest is that SSOI substrates provide higher carrier (electrons/holes) mobility than a conventional SOI substrate. The strain in the SSOI substrates can either be compressive or tensile.
Conventional methods to fabricate SSOI substrates typically require a layer transfer process wherein a strained Si-containing layer located on a relaxed SiGe layer is transferred onto a handle wafer. In particular, the conventional process includes first creating a relaxed SiGe layer of a few microns in thickness on a surface of a Si-containing substrate. The relaxed SiGe layer typically has an in-plane lattice parameter that is larger than that of Si. Next, a Si-containing layer is grown on the relaxed SiGe layer. Because the SiGe layer has a larger in-plane lattice parameter as compared to Si, the Si-containing layer is under strain.
The structure, including the strained Si-containing layer located on a relaxed SiGe layer, is then bonded to a handle wafer, which includes an insulating layer, such as an oxide layer. The bonding occurs between the strained Si-containing layer and the insulator layer. The Si-containing substrate and the relaxed SiGe layer are then typically removed from the bonded structure to provide a strained Si-on-insulator substrate.
The conventional SSOI substrate preparation method described above is quite expensive and low-yielding because it combines two rather advanced substrate technologies, i.e., high-quality, thick SiGe/strain Si growth, and wafer bonding. Moreover, the conventional preparation method is unattractive for manufacturing a large volume of substrates.
In view of the above, a cost effective and manufacturable solution to fabricate SSOI substrates is required for future high-performance Si-containing CMOS products.
SUMMARY OF THE INVENTION
The present invention provides a cost-effective and manufacturable solution to produce SSOI substrates that avoids wafer bonding which is typically required in conventional technologies to produce SSOI substrate materials. In particular, the method of the present invention, which fabricates SSOI substrates, includes creating a buried porous layer underneath a strained semiconductor layer. The porous layer is then converted into a buried oxide layer by employing a high temperature oxidation/anneal step such that only a part of the strained semiconductor layer is consumed during processing.
The method provides a SSOI substrate that includes a strained semiconductor layer atop an oxide layer, the oxide layer is located on a relaxed semiconductor template. Unlike the conventional process described above, the strained semiconductor layer and the relaxed semiconductor layer have a commensurate, i.e., identical, crystal orientation. Moreover, the oxide layer that is formed by the inventive method is of ‘high-quality’ meaning that the oxide layer has a leakage of about 1 microAmp or less and a breakdown field of about 2 Megavolts/cm or greater.
In broad terms, the method of the present invention comprises the steps of:
providing a structure that comprises a substrate, a relaxed semiconductor layer on the substrate, a doped and relaxed semiconductor layer on the relaxed semiconductor layer, and a strained semiconductor layer on the doped and relaxed semiconductor layer, said relaxed semiconductor layer, said doped and relaxed semiconductor layer and said strained semiconductor layer have identical crystallographic orientations;
converting the doped and relaxed semiconductor layer underneath the strained semiconductor layer into a buried porous layer; and
annealing the structure including the buried porous layer to provide a strained semiconductor-on-insulator substrate, wherein during said annealing the buried porous layer is converted into a buried oxide layer.
In addition to the method described above, the present invention also relates to the SSOI substrate that is formed. Specifically, the SSOI substrate of the instant invention comprises:
a substrate;
a relaxed semiconductor layer on the substrate;
a high-quality buried oxide layer on the relaxed semiconductor layer; and
a strained semiconductor layer on the high-quality buried oxide layer, wherein the relaxed semiconductor layer and the strained semiconductor layer have identical crystallographic orientations.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A–1D are pictorial representations (through cross sectional views) illustrating the basic processing steps employed in fabricating the inventive SSOI substrate. The inventive SSOI substrate shown in FIG. 1D contains a strained semiconductor layer and a buried oxide that are both unpatterned.
FIGS. 2A–2B are pictorial representations (through cross-sectional views) illustrating patterned SSOI substrates that are fabricated using the method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention, which provides a method of fabricating a SSOI substrate and the SSOI substrate produced by the method, will now be described in greater detail by referring to the drawings that accompany the present application. The drawings are provided for illustrative purposes only and are thus not drawn to scale. In the drawings, like and corresponding elements are referred to by like reference numerals.
The method of the present invention begins with first providing the structure 10 shown, for example, in FIG. 1A . Structure 10 includes a substrate 12 , a relaxed semiconductor, e.g., SiGe alloy, layer 14 located on a surface of substrate 12 , a doped and relaxed semiconductor layer 16 located on the relaxed semiconductor layer 14 , and a strained semiconductor layer 18 located on a surface of the doped and relaxed semiconductor layer 16 . In accordance with the present invention, layers 14 , 16 and 18 have the same crystallographic orientation since those layers are each formed by epitaxial growth.
Examples of various epitaxial growth processes that can be employed in the present invention in fabricating layers 14 , 16 and 18 on substrate 12 include, for example, rapid thermal chemical vapor deposition (RTCVD), low-energy plasma deposition (LEPD), ultra-high vacuum chemical vapor deposition (UHVCVD), atmospheric pressure chemical vapor deposition (APCVD) and molecular beam epitaxy (MBE).
The substrate 12 employed in the present invention may be comprised of any material or material layers including, for example, crystalline glass or metal, but preferably the substrate 12 is a crystalline semiconductor substrate. Examples of semiconductor substrates that can be employed as substrate 12 include, but are not limited to: Si, SiGe, SiC, SiGeC, GaAs, InAs, InP, and other III/IV or II/VI compound semiconductors. The term “semiconductor substrate” also includes preformed silicon-on-insulator (SOI) or SiGe-on-insulator (SGOI) substrates which may include any number of buried insulating (continuous, non-continuous or a combination of continuous and non-continuous) regions therein. In one preferred embodiment, the substrate 12 is a Si-containing substrate. The substrate 12 may be undoped or it may be an electron rich or hole-rich substrate, i.e., doped substrates.
The relaxed semiconductor layer 14 is then epitaxially grown on a surface of the substrate 12 using one of the above mentioned processes. In the following description the relaxed semiconductor layer 14 is referred to a relaxed SiGe layer 14 since that semiconductor material represents a preferred material for layer 14 . The term “SiGe alloy layer” denotes a SiGe layer that comprises up to 99 atomic percent Ge. More typically, the SiGe alloy layer comprises from about 1 to about 99 atomic percent Ge, with a Ge atomic percent from about 10 to about 50 atomic percent being more highly preferred.
The relaxed SiGe alloy layer 14 may be a single layer having a continuous distribution of Ge, or it may be a graded layer having a varying content of Ge included within different regions of the layer. As stated above, layer 14 is a relaxed layer having a measured degree of relaxation from about 10% or greater. Typically, the surface region of the relaxed semiconductor layer 14 is metastable having a defect (stacking faults, pile-up and threading) density that is typically about 1E5 defects/cm 3 or greater.
The relaxed semiconductor layer 14 may be doped or undoped. The type of dopant and concentration of dopant within the layer 14 is arbitrary and can be predetermined by a skilled artisan. When doped, relaxed layer 14 typically has a dopant concentration that is greater than 1E17 atoms/cm 3 . Doped layer 14 is formed by providing a dopant source with the Si source, or the Ge source, or both sources used during the epitaxial growth process.
The thickness of the relaxed semiconductor layer 14 may vary so long as a relaxed layer can be formed. The thickness of the relaxed semiconductor layer 14 is dependent on the Ge content of the layer. Typically, and for a relaxed semiconductor layer 14 having a Ge content of less than about 50 atomic %, layer 14 has a thickness from about 1 to about 5000 nm, with a thickness from about 1000 to about 3000 nm being more typical.
Although relaxed SiGe alloy templates are preferred, the present invention also contemplates the use of other semiconductor materials that can be formed in relaxed state.
Next, a doped and relaxed semiconductor layer 16 is formed on the relaxed semiconductor layer 14 . The doped and relaxed semiconductor layer 16 may include p- or n-type dopants, with p-type dopants being highly preferred. P-type dopants include Ga, Al, B and BF 2 . The doped and relaxed semiconductor layer 16 may be a separate layer, as shown in FIG. 1A , or it can be an upper portion of the previously formed relaxed semiconductor layer 14 . The term “semiconductor” when used in content with layer 16 denotes any semiconductor material including, for example, Si, SiGe, SiC, and SiGeC. Preferably, the doped and relaxed semiconductor layer 16 is a Si-containing semiconductor, with Si and SiGe being most preferred.
In accordance with the present invention, the doped and relaxed semiconductor layer 16 is a layer that is more heavily doped than the surrounding layers, i.e., layers 14 and 18 . Typically, the doped and relaxed semiconductor layer 16 contains a p-type dopant concentration of about 1E19 atoms/cm 3 or greater, with a p-type dopant concentration from about 1E20 to about 5E20 atoms/cm 3 being more typical. The doped and relaxed semiconductor layer 16 is formed using one of the above mentioned epitaxial growth processes in which the dopant source is included with the semiconductor source. The doped and relaxed semiconductor material 16 may have an in-plane lattice parameter that is either larger or smaller than that of virgin Si.
The doped and relaxed semiconductor layer 16 is a thin layer whose thickness will define the thickness of the buried oxide layer to be subsequently formed. Typically, the doped and relaxed semiconductor layer 16 has a thickness from about 1 to about 1000 nm, with a thickness from about 10 to about 200 nm being more typical.
After forming the doped and relaxed semiconductor layer 16 , a strained semiconductor layer 18 is formed on top of the doped and relaxed semiconductor layer 16 using one of the above-mentioned epitaxial growth processes. The strained semiconductor layer 18 may be comprised of one of the semiconductor materials mentioned above in connection with layer 16 . The strained semiconductor layer 18 and the doped and relaxed semiconductor 16 can thus be comprised of the same or different semiconductor material. The strained semiconductor 18 can have a tensile or compressive stress.
It is noted that the growth of layers 14 , 16 and 18 may occur using the same or different epitaxial growth process. Moreover, it is also contemplated to form layers 14 , 16 and 18 in the same reactor chamber without breaking vacuum.
The strained semiconductor layer 18 may be doped or undoped. When doped, the strained semiconductor layer 18 typically has a dopant concentration of about 1E15 atoms/cm 3 or greater. The thickness of layer 18 is typically from about 5 to about 2000 nm, with a thickness from about 10 to about 500 nm being more typical.
In one embodiment of the present invention, the strained semiconductor layer 18 and the doped and relaxed semiconductor layer 16 are comprised of the same or different Si-containing semiconductor, with Si or SiGe being highly preferred.
In a highly preferred embodiment of the present invention, the strained semiconductor layer 18 and the relaxed semiconductor layer 14 are both doped layers having a dopant concentration of about 1E15 atoms/cm 3 or greater, while the doped and relaxed semiconductor layer 16 is a p-doped layer having a dopant concentration of about 1E20 atoms/cm 3 or greater.
In accordance with the present invention, layers 14 , 16 and 18 have the same crystallographic orientation as substrate 12 since the various layers are formed by epitaxial growth. Hence, layers 14 , 16 and 18 can have a (100), (110), (111) or any other crystallographic orientation.
Next, the structure shown in FIG. 1A is subjected to an electrolytic anodization process that is capable of converting the doped and relaxed semiconductor layer 16 into a porous region. The structure, after the electrolytic anodization process has been performed, is shown, for example in FIG. 1B . In the drawing, reference numeral 20 denotes the porous region or layer.
The anodization process is performed by immersing the structure shown in FIG. 1A into an HF-containing solution while an electrical bias is applied to the structure with respect to an electrode also placed in the HF-containing solution. In such a process, the structure typically serves as the positive electrode of the electrochemical cell, while another semiconducting material such as Si, or a metal is employed as the negative electrode.
In general, the HF anodization converts the doped and relaxed semiconductor layer 16 into a porous semiconductor layer 20 . The rate of formation and the nature of the porous semiconductor layer 20 so-formed (porosity and microstructure) is determined by both the material properties, i.e., doping type and concentration, as well as the reaction conditions of the anodization process itself (current density, bias, illumination and additives in the HF-containing solution). Generally, the porous semiconductor layer 20 formed in the present invention has a porosity of about 0.1% or higher.
The term “HF-containing solution” includes concentrated HF (49%), a mixture of HF and water, a mixture of HF and a monohydric alcohol such as methanol, ethanol, propanol, etc, or HF mixed with at least one surfactant. The amount of surfactant that is present in the HF solution is typically from about 1 to about 50%, based on 49% HF.
The anodization process, which converts the doped and relaxed semiconductor layer 16 into a porous semiconductor layer 20 , is performed using a constant current source that operates at a current density from about 0.05 to about 50 milliAmps/cm 2 . A light source may be optionally used to illuminate the sample. More preferably, the anodization process of the present invention is employed using a constant current source operating at a current density from about 0.1 to about 5 milliAmps/cm 2 .
The anodization process is typically performed at room temperature or, a temperature that is elevated from room temperature may be used. Following the anodization process, the structure is typically rinsed with deionized water and dried. Anozidation typically occurs for a time period of less than about 10 minutes, with a time period of less than 1 minute being more typical.
The structure shown in FIG. 1B including the porous semiconductor layer 20 is then heated, i.e., annealed, at a temperature which converts the porous semiconductor layer 20 into a buried oxide region 22 . The resultant structure is shown, for example, in FIG. 1C . As shown, the structure includes a strained semiconductor layer 18 atop a buried oxide layer 22 . The buried oxide layer 22 is located atop the relaxed semiconductor layer 14 , which is, in turn, atop of the substrate 12 .
Note that an oxide layer 24 is formed atop layer 18 during the heating step. This surface oxide layer, i.e., oxide layer 24 , is typically, but not always, removed from the structure after the heating step using a conventional wet etch process wherein a chemical etchant such as HF that has a high selectivity for removing oxide as compared to semiconductor is employed. The structure, without the surface oxide layer 24 , is shown in FIG. 1D .
Note that when the oxide layer 24 is removed, the above processing steps can be repeated any number of times to provide a multilayered structure containing, from bottom to top, substrate/(relaxed semiconductor/buried oxide/strained semiconductor) x wherein x is greater than 1. When x is 1, the structure shown in FIG. 1D is formed.
In some embodiments of the present invention, multiple buried oxide layers can be obtained by forming continuous layers of materials 14 , 16 and 18 on substrate 12 and then performing the electrolytic anodization process and annealing process of the present invention.
The surface oxide layer 24 formed after the heating step of the present invention has a variable thickness which may range from about 10 to about 1000 nm, with a thickness of from about 20 to about 500 nm being more highly preferred. Buried oxide layer 22 typically has the same thickness as previously described for the doped and relaxed semiconductor layer 16 .
Specifically, the heating step of the present invention is an annealing step which is performed at a temperature that is greater than 400° C., preferably greater than 1100° C. A typical temperature range for the heating step of the present invention is from about 1200° to about 1320° C.
Moreover, the heating step of the present invention is carried out in an oxidizing ambient which includes at least one oxygen-containing gas such as O 2 , NO, N 2 O, ozone, air and other like oxygen-containing gases. The oxygen-containing gas may be admixed with each other (such as an admixture of O 2 and NO), or the gas may be diluted with an inert gas such as He, Ar, N 2 , Xe, Kr, or Ne. When a diluted ambient is employed, the diluted ambient contains from about 0.1 to about 100% of oxygen-containing gas, the remainder, up to 100%, being inert gas.
The heating step may be carried out for a variable period of time that typically ranges from greater than 0 minutes to about 1800 minutes, with a time period from about 60 to about 600 minutes being more highly preferred. The heating step may be carried out at a single targeted temperature, or various ramp and soak cycles using various ramp rates and soak times can be employed.
The heating step is performed under an oxidizing ambient to achieve the presence of oxide layers, i.e., layers 22 and 24 . Note that the porous semiconductor region reacts with diffused oxygen at an enhanced rate.
After heating, and subsequent removal of surface oxide layer 24 , the structure can be subjected to a thermal process (i.e., baking step) that is capable of reducing the content of dopants present in the final structure. The baking step is typically performed in the presence of a hydrogen-containing ambient such as H 2 . Leaching of dopants from the structure typically occurs when this step is performed at a temperature that is greater than 800° C., with a temperature of greater than 1000° C. being more typical. This thermal step is optional and does not need to be performed in all instances. Leaching of dopants using the thermal treatment process can be performed for any desired period of time.
Typically, the thermal process, which leaches dopants from the structure, is performed for a time period from about 1 to about 60 minutes. As stated above, this baking step reduces the amount of dopant within the SSOI substrate. Although it can be used to reduce any dopant within the SSOI substrate, it is particularly employed to remove boron from the structure.
After performing the above processing steps, conventional CMOS process can be carried out to form one or more CMOS devices such as field effect transistors (FETs) atop the strained semiconductor layer. The CMOS processing is well known to those skilled in the art; therefore details concerning that processing are not needed herein.
The method of the present invention described above provides a SSOI substrate including a strained semiconductor layer 18 atop an oxide layer 22 , the oxide layer 22 is located atop a relaxed semiconductor layer 14 which is located on a substrate 12 . Unlike the conventional process described above, the strained semiconductor layer 18 and the relaxed semiconductor layer 14 have a commensurate, i.e., identical, crystal orientation. Moreover, the oxide layer 22 that is formed by the inventive method is of ‘high-quality’ meaning that the buried oxide layer 22 has a leakage of about 1 microAmp or less and a breakdown field of about 2 Megavolts or greater.
The embodiment depicted in FIGS. 1A–1D illustrates the case wherein no layers are patterned. In another embodiment, it is also contemplated to form a structure that includes a patterned strained semiconductor layer 18 on a buried oxide layer 22 . One such patterned SSOI structure is shown, for example, in FIG. 2A . The patterned structure is formed using the same basic processing steps as described above except that prior to anodization the strained semiconductor layer 18 , shown, for example, in FIG. 1A , is patterned by lithography and etching. The lithography step includes applying a photoresist on the strained semiconductor layer 18 , exposing the photoresist to a pattern of radiation and developing the patterned into the exposed photoresist by utilizing a conventional resist developer. The etching step can include a wet etch process or a dry etching process that selectively removes the exposed strained semiconductor layer 18 . After stripping the patterned photoresist from the structure, anodization and oxidation, as described above, are performed. In some embodiments, the oxide layer 22 not underneath the strained semiconductor layer can be removed exposing the relaxed semiconductor layer 14 .
In yet another embodiment of the present invention, a patterned SSOI substrate, such as illustrated in FIG. 2B , can be formed. This patterned SSOI substrate is formed by first conducting the processing steps of epitaxial growth, anodization and oxidation, and then patterning the structure by lithography and etching. The etching step may be stopped atop a surface of oxide layer 22 providing the structure shown in FIG. 2A , or it can be stopped when a surface of the relaxed semiconductor layer 14 is reached, See FIG. 2B . The etch used in removing the exposed portions of both layer 18 and 22 can include a single etch step, or multiple etching steps may be employed.
CMOS processing can also be performed on the patterned SSOI substrates as well.
While the present invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in forms and details may be made without departing from the scope and the spirit of the present invention. It is therefore intended that the present invention not be limited to the exact forms and details described and illustrated, but fall within the scope of the appended claims. | A cost efficient and manufacturable method of fabricating strained semiconductor-on-insulator (SSOI) substrates is provided that avoids wafer bonding. The method includes growing various epitaxial semiconductor layers on a substrate, wherein at least one of the semiconductor layers is a doped and relaxed semiconductor layer underneath a strained semiconductor layer; converting the doped and relaxed semiconductor layer into a porous semiconductor via an electrolytic anodization process, and oxidizing to convert the porous semiconductor layer into a buried oxide layer. The method provides a SSOI substrate that includes a relaxed semiconductor layer on a substrate; a high-quality buried oxide layer on the relaxed semiconductor layer; and a strained semiconductor layer on the high-quality buried oxide layer. In accordance with the present invention, the relaxed semiconductor layer and the strained semiconductor layer have identical crystallographic orientations. | 8 |
FIELD
[0001] This invention relates to an epoxy resin composition and its application in marine maintenance and repair coating with improved overcoatability.
BACKGROUND
[0002] Epoxy resin is considered as the most cost-effective binder for anti-corrosion coating due to its excellent adhesion to metal, mechanical rigidity and chemical resistance properties. Epoxy primers are usually overcoated by a variety of topcoats, including solvent or water based epoxy, acrylate, polyurethane, polysiloxanes or other functional finishes.
[0003] There is an optimum time for epoxy to be overcoated, within this period no additional surface preparation is required. After the “overcoat window” has passed, the primer will need to be abraded before it can be topcoated, which is an expensive and labor-consuming process.
[0004] Overcoat window varies in each system according to the specific material and conditions applied. Temperature has significant influence on the overcoat window. 7 to 14 days are the typical overcoat window in most cases. Overcoating beyond the overcoat window will lead to weak intercoat adhesion and even paint failure, which causes significant scheduling issues or rework in the industry hampering throughput.
[0005] It is therefore, still interesting in the art to develop a coating having balanced overcoat window time and anti-corrosion properties.
SUMMARY
[0006] The present invention provides a curable composition comprising, based on the total weight of the curable composition: a) from 1 wt. % to 20 wt. % an epoxy compound I selecting from aromatic epoxy compounds, alicyclic epoxy compounds, or a mixture thereof; b) from 1 wt. % to 20 wt. % a chlorinated polyolefin based terpolymer; and c) from 1 wt. % to 40 wt. % a curing agent. It may further comprises from 0.4 wt. % to 10 wt. % an epoxy compound II selecting from acyclic aliphatic epoxy compounds.
[0007] Preferably, the epoxy compound I is bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, or a mixture thereof.
[0008] Preferably, the chlorinated polyolefin based terpolymer comprises from 5 to 20 mole percent structural units of vinyl chloride, from 4 to 10 mole percent structural units of vinyl acetate, and from 60 to 90 mole percent structural units of vinyl alcohol.
[0009] Optionally, the chlorinated polyolefin based terpolymer comprises from 5 to 20 mole percent structural units of vinyl chloride, from 70 to 90 mole percent structural units of vinyl acetate, and from 1 to 10 mole percent structural units of maleic acid.
[0010] Preferably, the epoxy compound II is glycerol diglycidyl ether, poly(propylene glycol)diglycidyl ether with an average molecular weight (Mw) from 300 to 1000, or the mixture thereof.
[0011] The present invention further provides a coating composition comprising, based on the total weight of the coating composition: a) from 25 wt. % to 45 wt. % a cured epoxy compound I selecting from aromatic epoxy compounds, alicyclic epoxy compounds, or a mixture thereof; b) from 1 wt. % to 20 wt. % a chlorinated polyolefin based terpolymer; and c) from 35 wt. % to 65 wt. % a filler. The coating composition may further comprises from 0.4 wt. % to 25 wt. % based on the total weight of the coating composition, a cured epoxy compound II selecting from acyclic aliphatic epoxy compounds.
DETAILED DESCRIPTION
[0012] As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably. The term “and/or” means one, one or more, or all of the listed items. The recitations of numerical ranges by endpoints include all numbers subsumed within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).
[0013] For one or more embodiments, the curable compositions include an epoxy composition comprising an epoxy compound I and optionally, an epoxy compound II. A compound is a substance composed of atoms or ions of two or more elements in chemical combination and an epoxy compound is a compound in which an oxygen atom is directly attached to two adjacent or non-adjacent carbon atoms of a carbon chain or ring system. The epoxy compound I can be from 1 weight percent to 20 weight percent of the curable composition; for example the epoxy compound can be from 3 weight percent to 16 weight percent or from 5 weight percent to 15 weight percent of the curable composition. In some embodiments that comprises epoxy compound II, it can be from 0.4 weight percent to 10 weight percent of the curable composition; for example the epoxy compound II can be from 1 weight percent to 8 weight percent or from 4 weight percent to 8 weight percent of the curable composition.
[0014] The epoxy compound I can be selected from the group consisting of aromatic epoxy compounds, alicyclic epoxy compounds, and combinations thereof.
[0015] The epoxy compound II can be selected from the group consisting of acyclic aliphatic epoxy compounds.
[0016] Examples of aromatic epoxy compounds include, but are not limited to, glycidyl ether compounds of polyphenols, such as hydroquinone, resorcinol, bisphenol A, bisphenol F, 4,4′-dihydroxybiphenyl, phenol novolac, cresol novolac, trisphenol (tris-(4-hydroxyphenyl)methane), 1,1,2,2-tetra(4-hydroxyphenyl)ethane, tetrabromobisphenol A, 2,2-bis(4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane, 1,6-dihydroxynaphthalene, and combinations thereof.
[0017] Examples of alicyclic epoxy compounds include, but are not limited to, polyglycidyl ethers of polyols having at least one alicyclic ring, or compounds including cyclohexene oxide or cyclopentene oxide obtained by epoxidizing compounds including a cyclohexene ring or cyclopentene ring with an oxidizer. Some particular examples include, but are not limited to, hydrogenated bisphenol A diglycidyl ether; 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexyl carboxylate; 3,4-epoxy-1-methylcyclohexyl-3,4-epoxy-1-methylhexane carboxylate; 6-methyl-3,4-epoxycyclohexylmethyl-6-methyl-3,4-epoxycyclohexane carboxylate; 3,4-epoxy-3-methylcyclohexylmethyl-3,4-epoxy-3-methylcyclohexane carboxylate; 3,4-epoxy-5-methylcyclohexylmethyl-3,4-epoxy-5-methylcyclohexane carboxylate; bis(3,4-epoxycyclohexylmethyl)adipate; methylene-bis(3,4-epoxycyclohexane); 2,2-bis(3,4-epoxycyclohexyl)propane; dicyclopentadiene diepoxide; ethylene-bis(3,4-epoxycyclohexane carboxylate); dioctyl epoxyhexahydrophthalate; di-2-ethylhexyl epoxyhexahydrophthalate; and combinations thereof.
[0018] The term “acyclic aliphatic epoxy compound” refers to a hydrocarbon compound having linear structure (straight or branched) onto which epoxides are attached. Besides hydrogen, other elements can be bound to the carbon chain; the most common examples are oxygen, nitrogen, sulphur, and chlorine. The acyclic aliphatic epoxy resin may be a monoepoxide compound or a compound containing two or more epoxy groups. Preferably, the acyclic aliphatic epoxy resin has two or more epoxy groups. The acyclic aliphatic epoxy resin may include acyclic aliphatic epoxides modified with glycols.
[0019] Acyclic aliphatic epoxy compounds include three identified types, epoxidized diene polymers, epoxidized oils and derivatives, and polyglycol diepoxides.
[0020] Epoxidized diene polymers are epoxidation of polymers containing ethylenic unsaturation which can by prepared by copolymerizing one or more olefins, particularly diolefins, by themselves or with one or more alkenyl aromatic hydrocarbon monomers. The copolymers may, of course, be random, tapered, block or a combination of these, as well as linear, star of radial. Diene polymers can be epoxidized include, but are not limited to, polymers of butadiene alone, random copolymers of butadiene and styrene, random copolymers of butadiene and (meta)acrylonitrile, block copolymers of butadiene and styrene, random copolymers of isoprene and styrene, random copolymers of isoprene and (meta)acrylonitrile, block copolymers of isoprene and styrene, and copolymers of butadiene and isoprene. In some cases, the copolymers of butadiene and isoprene may include vinyl compounds such as styrene and (meta)acrylonitrile.
[0021] Epoxidized oils and derivatives are epoxidized fatty acid esters. The oils from which these products are derived are naturally occurring long chain fatty acid sources, and there is considerable overlap in the composition of the fatty acid portion of these products. They are primarily the C 18 acids:oleic, linoleic, and linolenic acid. The alcohols are primary alcohols, diols or triols. This category consists of related fatty acid esters. Fatty acids, tall-oil, epoxidized, 2-ethylhexyl esters (ETP) 9-Octadecanoic acid (Z)-, epoxidized, ester w/propylene glycol (EODA) Epoxidized soybean oil (ESBO) Epoxidized linseed oil (ELSO or ELO). ETP is a monoester with 2-ethylhexanol. EODA is a diester with propylene glycol. ESBO and ELSO are triesters with glycerol (triglycerides).
[0022] Polyglycol diepoxides can be presented as formula I. The preferred compounds of formula I include those derived from ethylene and propylene glycols, in particular ethylene glycol and polyethylene glycol, with an average molecular weight of from 100 to 1500, preferably 200 to 800, in particular 600. In formula I, m preferably signifies 7 to 30, more preferably 7 to 14.
[0000]
[0023] R′ signifies hydrogen or methyl, and m signifies an integer of from 1 to 40,
[0024] Examples of polyglycol diepoxides include, but are not limited to, 1,4-butanediol diglycidyl ether, and 1,6-hexanediol diglycidyl ether; glycerol diglycidyl ether; a triglycidyl ether of glycerin; a triglycidyl ether of trimethylol propane; a tetraglycidyl ether of sorbitol; a hexaglycidyl ether of dipentaerythritol; a diglycidyl ether of polyethylene glycol, such as ethylene glycol diglycidyl ether, and diethylene glycol diglycidyl ether; and a diglycidyl ether of polypropylene glycol, such as, propylene glycol diglycidyl ether; polyglycidyl ethers of polyether polyols obtained by adding one type, or two or more types, of alkylene oxide to aliphatic polyols such as propylene glycol, trimethylol propane, and glycerin, such as, tripropylene glycol diglycidyl ether, and propylene glycol diglycidyl ether; diglycidyl esters of aliphatic long-chain dibasic acids; and combinations thereof.
[0025] An extensive enumeration of epoxy compounds useful in the present invention is found in Lee, H. and Neville, K., “Handbook of Epoxy Resins,” McGraw-Hill Book Company, New York, 1967, Chapter 2, pages 257-307.
[0026] Preferably, the epoxy compound I is aromatic epoxy compound obtained from the reaction of epichlorohydrin and a polyol, such as 4,4′-isopropylidenediphenol (bisphenol-A), more preferably, it is bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, or the mixture thereof. These epoxy resins are normally liquids or have a low molecular weight and are soluble in various aliphatic solvents such as ketones, esters, ether alcohols or any of the aromatic solvents such as xylene, etc.
[0027] Preferably, the epoxy compound I useful in the present invention for the preparation of the curable compositions, are selected from commercially available products. For example, D.E.R.™ 331, D.E.R.™ 332, D.E.R.™ 334, D.E.R.™ 337, D.E.R.™ 383, D.E.R.™ 580, D.E.R.™ 736, or D.E.R.™ 732 available from The Dow Chemical Company may be used. Most preferably, the epoxy compound I is a liquid epoxy resin, such as D.E.R.™ 331 having an average epoxide equivalent weight of 190 and D.E.R.™ 337 having an average epoxide equivalent weight of 240.
[0028] Preferably, the epoxy compound II is polyglycol diepoxides and polyglycol diepoxides modified with glycols, more preferably it is a diglycidyl ether of polypropylene glycol such as poly(propylene glycol)diglycidyl ether with an average molecular weight (Mw) from 300 to 1000 and glycerol diglycidyl ether.
[0029] For one or more embodiments, the curable compositions include a curing agent. The curing agent can be selected from the group consisting of novolacs, amines, anhydrides, carboxylic acids, phenols, thiols, and combinations thereof. The curing agent can be from 1 weight percent to 40 weight percent of the curable composition; for example the curing agent can be from 20 weight percent to 40 weight percent or from 25 weight percent to 35 weight percent of the curable composition.
[0030] For one or more of the embodiments, the curing agent can include a novolac. Examples of novolacs include phenol novolacs. Phenols can be reacted in excess, with formaldehyde in the presence of an acidic catalyst to produce phenol novolacs.
[0031] For one or more of the embodiments, the curing agent can include an amine. The amine can be selected from the group consisting of aliphatic polyamines, arylaliphatic polyamines, cycloaliphatic polyamines, aromatic polyamines, heterocyclic polyamines, polyalkoxy polyamines, dicyandiamide and derivatives thereof, aminoamides, amidines, ketimines, and combinations thereof. The preferred amine curing agents are the C 2 -C 10 polyamines that contain two or more reactive hydrogen groups and amine-terminated polyamide compositions, including those formed through the condensation of unsaturated fatty acids with C 2 -C 10 aliphatic polyamines having at least three amino groups per molecular. Sufficient amounts of the amine curing agent are employed to assure substantial crosslinking of the epoxide resin. Generally stoichiometric amounts or slight excess of the amine curing agent are employed Amine curing agents are normally used in amounts varying from 20-75 wt. percent based upon the type of the epoxy resin.
[0032] Examples of aliphatic polyamines include, but are not limited to, ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), trimethyl hexane diamine (TMDA), hexamethylenediamine (HMDA), N-(2-aminoethyl)-1,3-propanediamine (N3-Amine), N,N′-1,2-ethanediyl-bis-1,3-propanediamine (4-amine), dipropylenetriamine, and reaction products of an excess of these amines with an epoxy resin, such as bisphenol A diglycidyl ether.
[0033] Examples of arylaliphatic polyamines include, but are not limited to, m-xylylenediamine (mXDA), and p-xylylenediamine. Examples of cycloaliphatic polyamines include, but are not limited to, 1,3-bisaminocyclohexylamine (1,3-BAC), isophorone diamine (IPDA), 4,4′-methylenebiscyclohexaneamine, and bis(secondary amine) like JEFFLINK®754 from Huntsman Chemical Company.
[0034] Examples of aromatic polyamines include, but are not limited to, m-phenylenediamine, diaminodiphenylmethane (DDM), and diaminodiphenylsulfone (DDS). Examples of heterocyclic polyamines include, but are not limited to, N-aminoethylpiperazine (NAEP), 3,9-bis(3-aminopropyl) 2,4,8,10-tetraoxaspiro(5,5)undecane, and combinations thereof.
[0035] Examples of polyalkoxy polyamines include, but are not limited to, 4,7-dioxadecane-1,10-di amine; 1-propanamine; (2,1-ethanediyloxy)-bis-(diaminopropylated diethylene glycol) (ANCAMINE® 1922 A); poly(oxy(methyl-1,2-ethanediyl)), alpha-(2-aminomethylethyl)omega-(2-aminomethylethoxy) (JEFFAMINE® SD-231, SD-401, SD-2001); triethyleneglycoldiamine; and oligomers (JEFFAMINE® EDR-148, EDR-176); poly(oxy(methyl-1,2-ethanediyl)), alpha, alpha′-(oxydi-2,1-ethanediyl)bis(omega-(aminomethylethoxy)) (JEFFAMINE® XTJ-511); bis(3-aminopropyl)polytetrahydrofuran 350; bis(3-aminopropyl)polytetrahydrofuran 750; poly(oxy(methyl-1,2-ethanediyl)); a-hydro-(2-aminomethylethoxy) ether with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol (JEFFAMINE® T-403); diaminopropyl dipropylene glycol; and combinations thereof.
[0036] Examples of dicyandiamide derivatives include, but are not limited to, guanazole, phenyl guanazole, cyanoureas, and combinations thereof.
[0037] Examples of aminoamides include, but are not limited to, amides formed by reaction of the above aliphatic polyamines with a stoichiometric deficiency of anhydrides and carboxylic acids, as described in U.S. Pat. No. 4,269,742.
[0038] Examples of amidines include, but are not limited to, carboxamidines, sulfinamidines, phosphinamidines, and combinations thereof.
[0039] Examples of ketimines include compounds having the structure (R 2 ) 2 C═NR 3 , where each R 2 is an alkyl group and R 3 is an alkyl group or hydrogen, and combinations thereof.
[0040] For one or more of the embodiments, the curing agent can include phenalkamine. Phenalkamine is the condensation product of an alkyl phenol, aldehyde and one more at least difunctional amines and are known by the skilled man as Mannich bases: the reaction product of an aldehyde, such as formaldehyde, amine and an alkyl phenol (see WO 2004/024792 A1, page 3, lines 16-18). Useful amines include ethylenediamine (EDA), diethyltriamine (DETA) (see WO 2004/024792 A1, page 3, lines 18-19), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), m-xylylendiamine (MXDA), isophorone diamine, and the mixture thereof. Most preferably, a mixture of TETA and TEPA is used as amine mixture; the alkyl phenol is a cardanol-containing extract derived from cashew nutshell liquid (see WO 2004/024792 A1, page 3, lines 19-20).
[0041] For one or more of the embodiments, the curing agent can include an anhydride. An anhydride is a compound having two acyl groups bonded to the same oxygen atom. The anhydride can be symmetric or mixed. Symmetric anhydrides have identical acyl groups. Mixed anhydrides have different acyl groups. The anhydride is selected from the group consisting of aromatic anhydrides, alicyclic anhydrides, aliphatic anhydride, polymeric anhydrides, and combinations thereof.
[0042] Examples of aromatic anhydrides include, but are not limited to, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, pyromellitic anhydride, and combinations thereof.
[0043] Examples of alicyclic anhydrides include, but are not limited to methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl nadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, and combinations thereof.
[0044] Examples of aliphatic anhydrides include, but are not limited to, propionic anhydride, acetic anhydride, and combinations thereof.
[0045] Example of a polymeric anhydrides include, but are not limited to, polymeric anhydrides produced from copolymerization of maleic anhydride such as poly(styrene-co-maleic anhydride) copolymer, and combinations thereof.
[0046] For one or more of the embodiments, the curing agent can include a carboxylic acid. Examples of carboxylic acids include oxoacids having the structure R 4 C(═O)OH, where R 4 is an alkyl group or hydrogen, and combinations thereof.
[0047] For one or more of the embodiments, the curing agent can include a phenol. Examples of phenols include, but are not limited to, bisphenols, novolacs, and resoles that can be derived from phenol and/or a phenol derivative, and combinations thereof.
[0048] For one or more of the embodiments, the curing agent can include a thiol. Examples of thiols include compounds having the structure R 5 SH, where R 5 is an alkyl group, and combinations thereof.
[0049] The curable composition of the present invention further comprises from 1 wt. % to 20 wt. % based on the total weight of the curable composition, a chlorinated polyolefin based terpolymer. Preferably, it is from 3 wt. % to 13 wt. %.
[0050] In one embodiment, the chlorinated polyolefin based terpolymer is a terpolymer of vinyl chloride, vinyl acetate, and vinyl alcohol. It contains vinyl chloride repeat units in an amount of from about 5% to about 20% mole percent, vinyl alcohol repeat units in an amount of from about 60% to about 90% mole percent, and vinyl acetate repeat units in an amount of from about 4% to about 10% mole percent. Preferably, the terpolymer contains vinyl chloride repeat unites in an amount of from about 14% to about 15% mole percent, vinyl alcohol repeat units in an amount of from about 70% to about 80% mole percent, and vinyl acetate repeat units in an amount of from 1% to about 5% mole percent, although the relative amounts of monomers can be outside of these ranges.
[0051] The terpolymer of vinyl chloride, vinyl acetate, and vinyl alcohol typically has a weight average molecular weight (Mn) of from about 25000 to about 40000 and more preferably from about 30000 to about 35000, although the weight average molecular weight can be outside of these ranges.
[0052] Suitable poly(vinyl chloride-vinyl alcohol-vinyl acetate) terpolymers can be prepared by, for example, high pressure free radical polymerization of vinyl chloride with vinyl acetate in a suitable solvent, such as water, benzene, toluene, cyclohexane, or the like, to from a poly(vinyl chloride-vinyl acetate) copolymer, followed by hydrolysis of the poly(vinyl chloride-vinyl acetate) copolymer to obtain a poly(vinyl chloride-vinyl alcohol-vinyl acetate) terpolymer.
[0053] One commercial product of such suitable poly(vinyl chloride-vinyl alcohol-vinyl acetate) terpolymers is CONVINYL® G-75 with Mn equaling to about 32000, Vac content being 4%, and hydroxyl value being 75 from Connell Bros. Company LTD.
[0054] In another embodiment, chlorinated polyolefin based terpolymer is a terpolymer of vinyl chloride, vinyl acetate, and maleic acid. It contains vinyl chloride repeat units in an amount of from about 5% to about 20% mole percent, vinyl acetate repeat units in an amount of from about 70% to about 90% mole percent, and maleic acid repeat units in an amount of from about 1% to about 10% mole percent. Preferably, the terpolymer contains vinyl chloride repeat units in an amount of from about 10% to about 15% mole percent, vinyl acetate repeat units in an amount of from about 80% to about 90% mole percent, and maleic acid repeat units in an amount of from 1% to about 5% mole percent, although the relative amounts of monomers can be outside of these ranges.
[0055] The terpolymer typically has a weight average molecular weight (Mn) of from about 20000 to about 40000 and more preferably from about 28000 to about 32000, although the weight average molecular weight can be outside of these ranges.
[0056] Suitable poly(vinyl chloride-vinyl acetate-maleic acid) terpolymers can be prepared by, for example, high pressure free radical polymerization of vinyl chloride with vinyl acetate and maleic acid in a suitable solvent, such as water, benzene, toluene, cyclohexane, or the like, to from a poly(vinyl chloride-vinyl acetate-maleic acid) terpolymer.
[0057] One commercial product of such suitable poly(vinyl chloride-vinyl alcohol-vinyl acetate) terpolymers is CONVINYL® C-47 with Mn equaling to 29000 and Vac:Vcm:Mal being 13:86:1 from Connell Bros. Company LTD.
[0058] For one or more embodiments, the curable compositions can include a catalyst. Examples of the catalyst include, but are not limited to, 2-methyl imidazole, 2-phenyl imidazole, 2-ethyl-4-methyl imidazole, 1-benzyl-2-phenylimidazole, boric acid, triphenylphosphine, tetraphenylphosphonium-tetraphenylborate, and combinations thereof. The catalyst can be used in an amount of from 0.01 to 5 parts per hundred parts of the epoxy compound; for example the catalyst can be used in an amount of from 0.05 to 4.5 parts per hundred parts of the epoxy compound or 0.1 to 4 parts per hundred parts of the epoxy compound.
[0059] For one or more embodiments, the curable compositions can include an inhibitor. The inhibitor can be a Lewis acid. Examples of the inhibitor include, but are not limited to, boric acid, halides, oxides, hydroxides and alkoxides of zinc, tin, titanium, cobalt, manganese, iron, silicon, boron, aluminum, and combinations thereof. Boric acid as used herein refers to boric acid or derivatives thereof, including metaboric acid and boric anhydride. The curable compositions can contain from 0.3 mole of inhibitor per mole of catalyst to 3 mole of inhibitor per mole of catalyst; for example the curable compositions can contain from 0.4 moles of inhibitor per mole of catalyst to 2.8 mole of inhibitor per mole of catalyst or 0.5 mole of inhibitor per mole of catalyst to 2.6 mole of inhibitor per mole of catalyst.
[0060] The curable composition may also include one or more optional additives conventionally found in epoxy resin systems to form the coating composition of the present invention. For example, the curable composition of the present invention may contain additives such as nonreactive and reactive diluents; catalyst; other curing agents; other resins; fibers; coloring agents; thixotropic agents, photo initiators; latent photo initiators, latent catalysts; inhibitors; flow modifiers; accelerators; desiccating additives; surfactants; adhesion promoters; fluidity control agents; stabilizers; ion scavengers; UV stabilizers; flexibilizers; fire retardants; diluents that aid processing; toughening agents; wetting agents; mold release agents; coupling agents; tackifying agents; and any other substances which are required for the manufacturing, application or proper performance of the composition.
[0061] Fillers are used to control the viscosity, rheology, shelf stability, specific gravity and cured performance properties, such as corrosion resistance, impact resistance and abrasion resistance. The fillers may be spherical or platy. As used herein platy means the particles have a high aspect ratio. High aspect ratio fillers include as talc, mica and graphite. Preferred high aspect ratio fillers include mica having a median particle size of 20 to 70 microns (micrometers) and most preferably 50 microns (micrometers). Examples of fillers include such as wollastonite, barites, mica, feldspar, talc, silica, crystalline silica, fused silica, fumed silica, glass, metal powders, carbon nanotubes, grapheme, calcium carbonate, and barium sulphate; aggregates such as glass beads, polytetrafluoroethylene, polyol resins, polyester resin, phenolic resins, graphite, molybdenum disulfide and abrasive pigments; viscosity reducing agents; boron nitride; nucleating agents; dyes; pigments such as titanium dioxide, carbon black, iron oxides, chrome oxide, and organic pigments.
[0062] The coating composition of the present invention is made by batch mixing the necessary components under high speed, high shear agitation. The process includes three steps: all liquid resins, curatives and platy fillers are mixed first for 20 minutes and degassed at 30 mHg; spherical fillers and glass spheres are added and the mixture is mixed for 20 minutes and degassed at 30 mmHg; fumed silica is then added and the mixture is mixed for 10 minutes and degassed at 30 mmHg.
[0063] Other information related with the coating preparation is listed in patent: US20100048827(A1).
[0064] The coating composition of the present invention comprises based on the total weight of the coating composition a) from 25 wt. % to 45 wt. %, preferable from 30 wt. % to 45 wt. %, most preferably from 30 wt. % to 40 wt. %, a cured epoxy compound I; b) from 1 wt. % to 20 wt. %, preferably from 3 wt. % to 13 wt. %, a chlorinated polyolefin based terpolymer; and c) from 35 wt. % to 65 wt. %, preferably from 40 wt. % to 60 wt. %, most preferably from 45 wt. % to 60 wt. %, a filler.
[0065] In some embodiments, the coating composition of the present invention further comprises from 0.1 wt. % to 25 wt. %, preferably from 5 wt. % to 20 wt. %, most preferably from 10 wt. % to 15 wt. %, a cured epoxy compound II;
EXAMPLES
I. Raw Materials
[0066]
[0000]
TABLE 1
Starting materials used in paint formulation
Material
Function
Chemical nature
Supplier
Xylene
solvent
C 6 H 4 (CH 3 ) 2
Sinopharm Chemical Reagent Co., Ltd
BYK-P 104 S
wetting and dispersing additive
BYK Company
Cravallac Ultra
Rheology modifier
Sinopharm Chemical Reagent Co., Ltd
N-butanol
solvent
C 4 H 10 O
Sinopharm Chemical Reagent Co., Ltd
Titanium Dioxide
filler
TiO 2
Sinopharm Chemical Reagent Co., Ltd
Universal
D.E.R. 337-X-80
epoxy
DOW Chemical Company
Mica filler
filler
SiO 2 , MgO
Sinopharm Chemical Reagent Co., Ltd
D.E.R. 331
epoxy
Sinopharm Chemical Reagent Co., Ltd
Barium sulphate
filler
BaSO 4
Sinopharm Chemical Reagent Co., Ltd
Silica powder
filler
SiO 2
Sinopharm Chemical Reagent Co., Ltd
Phenalkamine
Curing agent
AkzoNobel Company
CONVINYL ® C-47
additive
Connell Bros Company
CONVINYL ® G-75
additive
Connell Bros Company
II. Test Procedures
[0067] Overcoat window was determined by cross hatch tape test according to ASTM D3359-02 following the assessment protocol as:
a) Apply coatings onto Q-panels at a wet film thickness of 200 um;
b) Allow each coating to achieve a tack free state;
c) Age coatings under natural light for a set period (1 day to 6 months);
d) Top coat with acrylic surface coat at a wet film thickness of 200 um;
e) Cure at room temperature for at least 5 days;
f) Subject to the cross hatch tape test;
The definition of the overcoat window:
The overcoat window was determined by the adhesion test result by cross hatch tape test. The different classifications of cross hatch tape test were listed in Table 2. Overcoat window was determined when the adhesion between top coat and primer begin to decrease from 5B to 4B.
[0000] TABLE 2 Cross Hatch Tape Test (ASTM D3359-02) Surface of cross-cut area from which flaking has occurred for Classification Percent area removed six parallel cuts and adhesion range by percent 5B 0% None 4B Less than 5% 3B 5-15% 2B 15-35% 1B 35-65%
Chemical resistance test and salt spray resistance test were also conducted to evaluate anti-corrosion performance.
Chemical Resistance Test:
[0068] Tampons were stained with 10 wt. % sodium hydroxide solution or 10 wt. % sulfuric acid solution and put onto coating surface for different days. Plastic bottles were used to cover up the health cottons with chemicals to restrict water evaporation. Four rate scales were used:
E: Excellent G: Good F: Fair P: Poor
[0069]
[0000]
TABLE 3
Standard test method for evaluating degree of blistering
of paints (ASTM D714-02), 5% NaCl salt spray test.
Rust
Visual Examples
Grade
Percent of surface rusted
Spot(s)
General(G)
Pinpoint(P)
10
Less than or equal to
0.01 percent
9
Greater than 0.01 percent
9-S
9-G
9-P
and up to 0.03 percent
8
Greater than 0.03 percent
8-S
8-G
8-P
and up to 0.1 percent
7
Greater than 0.1 percent
7-S
7-G
7-P
and up to 0.3 percent
6
Greater than 0.3 percent
6-S
6-G
6-P
and up to 1.0 percent
5
Greater than 0.01 percent
5-S
5-G
5-P
and up to 0.03 percent
4
Greater than 3.0 percent
4-S
4-G
4-P
and up to 10.0 percent
3
Greater than 10.0 percent
3-S
3-G
3-P
and up to 16.0 percent
2
Greater than 16.0 percent
2-S
2-G
2-P
and up to 33.0 percent
1
Greater than 33.0 percent
1-S
1-G
1-P
and up to 50.0 percent
0
Greater than 50.0 percent
None
III. Examples
[0070] Primers were prepared according to the formulation listed in Table 4. Solid content is 77%, the epoxide group content is 1.145 mmol/g.
[0000]
TABLE 4
Primer formulations
Component
wt. %
Xylene (solvent)
16.33
BYK-P 104 S (wetting and dispersing additive)
0.35
Cravallac Ultra (rheology modifier)
0.92
N-butanol (solvent)
1.42
Titanium Dioxide Universal (filler)
2.30
D.E.R. 337-X-80 (epoxy)
5.83
Mica (filler)
5.38
D.E.R. 331 (epoxy)
11.57
Barium sulphate (filler)
14.17
Silica powder (filler)
21.47
Example 1
[0071] Primers were prepared according to the formulation listed in Table 1. Solid content is 77%. Charged 15 g primer (77% solid) and 0.75 g CONVINYL® G-75 (vinyl chloride/vinyl acetate/vinyl alcohol copolymer, 50% solid, Mn=32000, Vac content 4%, Hydroxyl value 75, Connell Bros. Company LTD.) and 6.67 g phenalkamine curing agent, stirred for 10 minutes. The thoroughly mixed solution was removed from the mixer and allowed to stay static for 2-5 minutes to remove gas bubbles. The above formulation was coated using blade coater on a Q-panel. A wet coating with a thickness of 200 μm was applied to clean Q-panels (H. J. Unkel LTD. Company). The coated panels were allowed to dry at room temperature for a set period prior to coating with top coat. Cross hatch tape test was conducted when top coat was completely dried. Salt spray test and chemical resistance test were also conducted to evaluate the anti-corrosion performance.
Example 2
[0072] 15 g Primer (77% solid) and 1.5 g CONVINYL® G-75 (vinyl chloride/vinyl acetate/vinyl alcohol copolymer, 50% solid, Mn=32000, Vac content 4%, Hydroxyl value 75, Connell Bros. Company LTD.) and 6.67 g phenalkamine curing agent were charged. The preparing process is the same as in Example 1. The coated panels were allowed to dry at room temperature for a set period prior to coating with top coat. Cross hatch tape test was conducted when top coat was completely dried. Salt spray test and chemical resistance test were also conducted to evaluate the anti-corrosion performance.
Example 3
[0073] 15 g Primer (77% solid) and 3 g CONVINYL® G-75 (vinyl chloride/vinyl acetate/vinyl alcohol copolymer, 50% solid, Mn=32000, Vac content 4%, Hydroxyl value 75, Connell Bros. Company LTD.) and 6.67 g phenalkamine curing agent were charged. The preparing process is the same as in Example 1. The coated panels were allowed to dry at room temperature for a set period prior to coating with top coat. Cross hatch tape test was conducted when top coat was completely dried. Salt spray test and chemical resistance test were also conducted to evaluate the anti-corrosion performance.
Example 4
[0074] 15 g Primer (77% solid) and 1.5 g CONVINYL® C-47 (chloride/vinyl acetate/maleic acid terpolymer, 50% solid, Mn=29000, Vac:Vcm:Mal=13:86:1, Connell Bros. Company LTD.) and 6.67 g phenalkamine curing agent were charged. The preparing process is the same as in Example 1. The coated panels were allowed to dry at room temperature for a set period prior to coating with top coat. Cross hatch tape test was conducted when top coat was completely dried. Salt spray test and chemical resistance test were also conducted to evaluate the anti-corrosion performance.
Example 5
[0075] 15 g Primer (77% solid) and 3 g CONVINYL® C-47 (chloride/vinyl acetate/maleic acid terpolymer, 50% solid, Mn=29000, Vac:Vcm:Mal=13:86:1, Connell Bros. Company LTD.) and 6.67 g phenalkamine curing agent were charged. The preparing process is the same as in Example 1. The coated panels were allowed to dry at room temperature for a set period prior to coating with top coat. Cross hatch tape test was conducted when top coat was completely dried. Salt spray test and chemical resistance test were also conducted to evaluate the anti-corrosion performance.
Comparative Example 1
[0076] 15 g Primer (77% solid) and 6.67 g phenalkamine curing agent were charged. The preparing process is the same as in Example 1. The coated panels were allowed to dry at room temperature for a set period prior to coating with top coat. Cross hatch tape test was conducted when top coat was completely dried. Salt spray test and chemical resistance test were also conducted to evaluate the anti-corrosion performance.
Comparative Example 2
[0077] 15 g Primer (77% solid) and 0.75 g poly(vinyl chloride) (average Mn=30000) and 6.67 g phenalkamine curing agent, mixed and stirred for 30 minutes. However, vinyl chloride was difficult to be completely dissolved with xylene, even after adding some methyl ethyl ketone into the primer system. So it has solubility issue for directly mixing poly(vinyl chloride) powder mixed into epoxy system.
IV. Results
[0078]
[0000] TABLE 4 Coating properties from the examples Alkali Acid Salt spray Impact Overcoat resistance resistance test, Rust resistance Contact Primer/ window (10% (10% grade (cm/lb), Pendulum Tg angle Example Curing agent Terpolymer time (d) NaOH) H 2 SO 4 ) (1000 h) Q-panel Hardness (° C.) (°) Comp. 1 D.E.R. None 7 P E 5 70 119 71.8 54.1 331 + D.E.R.337/ phenalkamine 1 D.E.R. CONVINYL ® 14 G E 6 76 81 67.5 79.2 331 + D.E.R.337/ G-75 phenalkamine 2 D.E.R. CONVINYL ® 30 G E 8 76 81 64.1 80.7 331 + D.E.R.337/ G-75 phenalkamine 3 D.E.R. CONVINYL ® 60 F G 9 100 102 57.9 55.4 331 + D.E.R.337/ G-75 phenalkamine 4 D.E.R. CONVINYL ® 30 G E 8 60 98 70.2 78.9 331 + D.E.R.337/ C-47 phenalkamine 5 D.E.R. CONVINYL ® 60 F G 7 85 100 67.5 68.1 331 + D.E.R.337/ C-47 phenalkamine
Table 4 summarizes the properties of various coatings used in this research. With the blending of vinyl chloride/vinyl acetate/vinyl alcohol copolymer CONVINYL® G-75 or vinyl chloride/vinyl acetate/maleic acid terpolymer CONVINYL® C-47, all the coatings have improved overcoatability windows and slightly improved anti-corrosion properties and chemical resistance ability. Glass transition temperature (Tg) of vinyl chloride polymer modified primers decreased a little comparing to that of comparative example 1. The impact resistance, Pendulum hardness and contact angles of the coatings cured for 30 days at room temperature were tested. These parameters vary with different dosages and are acceptable. | This invention relates to an epoxy resin composition and its application in marine maintenance and repair coating with improved overcoatability. | 2 |
RELATED APPLICATIONS
This application is a Continuation of parent application Ser. No. 08/387,279, filed 13 Feb. 1995, entitled TAMPER-EVIDENT RING, and abandoned upon the filing of this Continuation application.
FIELD OF INVENTION
The invention relates to tamper-evident rings, such as seals and key rings that incorporate security features to inhibit undetected opening or reclosing of the rings.
BACKGROUND
Key rings are commonplace, and most such rings are arranged for keys to be routinely removed or replaced from the rings. However, in high security areas such as jails, a closer accounting of keys is necessary to prevent unauthorized use or copying of the keys. Accordingly, some security key rings are arranged for permanently mounting keys on continuous key rings to prevent their removal or replacement.
For example, security key rings have been fashioned from stainless steel bar stock having a standard cross-sectional diameter of approximately four millimeters to accommodate openings in most keys. The bar stock is bent in the form of a split ring, and keys are mounted on the ring. The split ring is then welded closed to form a continuous ring, which must be cut apart to remove any keys. However, the welded joint increases the cross-sectional diameter of the ring and adds significant cost and time to the assembly of the key rings.
U.S. Pat. No. 2,432,870 to Evalt discloses a continuous key ring made of plastic. A helical segment of the plastic is formed with two mating ends. After mounting a key and a tag, the mating ends are aligned and a solvent is applied to form a fusion weld at the joint. The plastic ring can be easily severed for separating the key and tag, and another plastic ring can be used for linking the key to a different tag. However, such plastic rings are not strong enough to be used in high security areas, where continuous key rings are required to hold more keys and to prevent the keys from being easily removed.
While it is important to structurally inhibit the removal of keys by using strong materials, their removal cannot be entirely prevented, so it is also important to detect their removal or replacement. Both the plastic ring of Evalt and the stainless steel security rings currently in use can be rewelded closed without any signs that they had been opened.
A variety of tamper-evident designs for locks and other security devices are known, but none are suitable for use with continuous key rings that have a limited cross-sectional dimension. For example, U.S. Pat. No. 4,893,853 to Guiler discloses a tamper-evident padlock in which forced attempts to remove a shackle from the padlock body cause shackle ends to rupture the padlock body. U.S. Pat. No. 4,782,564 to Sloan discloses a safety release pin for a fire extinguisher that, upon removal, fractures a locking mechanism to provide a visual indication that the device has been used. Neither of these tamper-evident designs could be used within the confines of a continuous key ring.
SUMMARY OF INVENTION
My invention provides for incorporating tamper-evident features into continuous rings. A single-use interlock combines a seal with a high strength connector for joining ends of a split ring into a continuous ring that cannot be reopened without breaking the interlock. This prevents the continuous ring from being reclosed and provides a visual indication that the ring has been reopened.
One example of my invention includes a split ring that is made from a strong resilient material, such as stainless steel, having a given maximum cross-sectional diameter for mounting security keys. A male fitting is formed at one end of the split ring, and a female fitting is formed at the other end of the split ring. The male and female fittings interconnect to form a joint that has a cross-sectional diameter no larger than the maximum cross-sectional diameter of the split ring. One of the fittings is breakable for disconnecting the two fittings and for preventing the fittings from being reconnected.
The male fitting has head and neck portions, and the female fitting has a socket portion. The two fittings are joined within a region of overlap by crimping the socket portion of the female fitting over the head portion of the male fitting. A hardened wheel of a crimping tool forms an annular indentation that is pressed toward the neck portion of the male fitting adjacent to the head portion of the same fitting. The indentation weakens the socket portion and renders the socket portion susceptible to breakage if force is used to separate the two fittings. The broken socket cannot be reused to interconnect the two ends of the split ring. The breakage is also readily observable as evidence of tampering.
Another example of my invention modifies the socket to capture a snap-ring, which can be contracted for insertion past detents at the open end of the socket. The head portion of the male fitting is beveled to temporarily expand the snap-ring until the snap-ring has sprung in place around the neck portion of the male fitting. The two fittings cannot be separated without breaking one of the fittings.
DRAWINGS
FIG. 1 is a plan view of one example of my new tamper-evident key ring.
FIG. 2 is an enlarged view of male and female fittings at open ends of the key ring with the female fitting shown in cross section.
FIG. 3 is a similarly enlarged view of the male and female fittings closed together.
FIG. 4 is a plan view of a pair of vise grips for squeezing the key ring.
FIG. 5 is a side view of a crimping tool for joining the male and female fittings.
FIG. 6 is a plan view of the closed ring showing positions at which the vise grips and crimping tool engage the ring.
FIG. 7 is a plan view of round bar stock that is machined at opposite ends to form the male and female fittings.
FIG. 8 is an enlarged view of an alternative pair of male and female fittings with the female fitting shown in cross section.
FIG. 9 is a similarly enlarged view of the alternative fittings closed together.
FIG. 10 is an isometric view of a snap-ring for interconnecting the alternative pair of male and female fittings.
DETAILED DESCRIPTION
A preferred embodiment of my invention is a tamper-evident key ring 10 as shown in FIGS. 1-3. The key ring 10 has a split-ring body 12 that is preferably made from a strong resilient material such as stainless steel. Some softer materials could also be used, but I prefer these to exhibit ultimate tensile strength of at least 100 megapascals. Also, the split-ring body 12 preferably has a constant cross-sectional diameter no more than 6 millimeters; and in most instances, the cross-sectional diameter should be 4 millimeters.
A male fitting 14 is formed at one end of the split-ring body 12, and a female fitting 16 is formed at the other end of the split-ring body 12. The male fitting 14 has a head portion 18 that is supported from the split-ring body 12 by a narrower neck portion 20. As shown best in FIG. 2, the head portion 18 is joined to the neck portion 20 by a ledge 19 that forms a right-angle interface making a sheer diametrical variation between the head and neck portions 18 and 20. The female fitting 16 has a socket portion 22 that is sized for encompassing the head and neck portions 18 and 20 of the male fitting 14. A periphery of the female fitting 16 is encircled by a groove 24 for guiding a crimping tool 56 (see FIGS. 5 and 6). The groove 24 is aligned with a junction where the head portion 18 meets the neck portion 20 of the male fitting 14 when the two fittings 14 and 16 are closed together.
Most of the split-ring body 12 is bent at a single curvature having a center of curvature 26. However, the split-ring body 12 also includes straight sections 28 and 30 that are adjacent to the male and female fittings 14 and 16. The two straight sections 28 and 30 are connected to the remaining portion of the split-ring body 12 by more abruptly curved sections 32 and 34 having centers of curvature 36 and 38. The two more abruptly curved sections 32 and 34 provide for aligning the two straight sections 28 and 30 when the two fittings 14 and 16 are closed together. A laser-etched serial number 39 distinguishes each split-ring body 12 to prevent substitutions.
FIGS. 4-6 show tooling for crimping the male and female fittings 14 and 16 together. An adjustable pair of vise grips 40 are shown in FIG. 4. The vise grips 40 include two specialized jaws 42 and 44 that are adjustably supported by conventional handles 46 and 48. Slots 50 and 52 in ends of the jaws 42 and 44 are sized for gripping opposite sides of the split ring 12. Set screw 54 adjusts a minimum spacing between the jaws 42 and 44 for closing the split ring 12 as shown in FIGS. 3 and 6.
A crimping tool 56 for joining the male and female fittings 14 and 16 within a region of overlap is shown in FIG. 5. The female fitting 16 is engaged between a hardened wheel 58 and two rollers 60 and 62. Pressure between the hardened wheel 58 and the female fitting 16 is applied by a screw 64 that adjusts spacing between the hardened wheel 58 and the two rollers 60 and 62. A raised ridge 66 of the hardened wheel 58 tracks along the groove 24 while the crimping tool 56 is rotated around the female fitting 16. While continuing to rotate under pressure, the hardened wheel 58 swages a ring of material from the socket portion 22 of the female fitting 16 toward the neck portion 20 and against the ledge 19 of the male fitting 14 until shoulders 68 of the hardened wheel 58 contact the female fitting 16. A mechanical stop could also be used to limit penetration of the hardened wheel 58.
Although the annular crimp forms a strong bond between the male and female fittings 14 and 16, the swaged material forming the crimp is further hardened and made more brittle than the remaining material of the key ring 10. Also, the deepened groove 24 concentrates stress forces so that the female fitting 16 is fractured into two parts by unauthorized separation of the male and female fittings 14 and 16. Once fractured, the female fitting 16 can not be rejoined with the male fitting 14. The fractured fitting also provides a clear visual indication that the ring 10 has been reopened.
The illustrated key ring 10 can be made from a round bar stock 70 (see FIG. 7) having a constant cross-sectional diameter. The bar stock 70 is cut to a given length. The male fitting 14 is formed at one end of the length, and the female fitting 16 is formed at the other end of the length. The head and neck portions 18 and 20 of the male fitting 14 are preferably machined in a turning operation. The socket portion 22 of the female fitting 16 is preferably bored. The groove 24 in the female fitting 16 can also be formed by turning. Thereafter, the bar stock is bent to form the split-ring body 12 as depicted in FIG. 1.
One or more keys 72 can be mounted on the split-ring body 12 by passing one of the two fittings 14 and 16 through respective openings in the keys 72. The two fittings 14 and 16 are squeezed together by the vise grips 40 against a restorative force of the split-ring body 12 so that the head and neck portions 18 and 20 of the male fitting are inserted into the socket portion 22 of the female fitting (see FIG. 6). The crimping tool 56 is mounted on the straight sections 28 and 30 of the split-ring body 12, and the raised ridge 66 of the hardened wheel 58 is aligned with the groove 24 in the female fitting 16. The screw 64 of the crimping tool 56 is turned to apply pressure while the crimping tool 56 is rotated to seal the male and female fittings 14 and 16 together. After the vise grips 40 and the crimping tool 56 are removed, the keys 72 can slide 360 degrees around the key ring 10.
The remaining drawing FIGS. 8-10 illustrate alternative male and female fittings 74 and 76 for sealing opposite ends of a split-ring body 98. Similar to the preceding embodiment, the male fitting 74 includes head and neck portions 78 and 80, and the female fitting 76 includes a socket portion 82. However, the female fitting 76 also includes a detent 84 that is formed as an annular lip at an open end 94 of the socket portion 82. The head portion 78 of the male fitting 74 is relatively sized to fit through the detent 84 into the socket portion 82 of the female fitting 76.
The male and female fittings 74 and 76 are held together by a snap-ring 86 that is captured within the socket portion 82 of the female fitting 76 by the detent 84. The snap-ring 86 is made out of a brittle yet resilient material, such as hardened steel, and has a split-sleeve body 88 with a tab 90 that extends from one end. The split-sleeve body 88 can be temporarily compressed to fit the snap-ring 86 through the detent 84 into position within the socket portion 82 of the female fitting.
The head portion 78 of the male fitting has a beveled end face 92 for temporarily expanding the split-sleeve body 88 while the male fitting 74 is first inserted into the female fitting 76. The tab 90 spaces the split-sleeve body 88 from a closed end 96 of the socket portion 82 until the split-sleeve body 88 has sprung into place around the neck portion 80 of the male fitting. The split-sleeve body 88 of the snap-ring 86 captures the head portion 78 of the male fitting, and the detent 84 of the female fitting captures the split-sleeve body 88. Once joined, the male and female fittings 74 and 76 cannot be separated without breaking.
Although my tamper-evident ring has been described for use as a key ring, a variety of other uses will also be apparent to those of skill in this art. For example, my ring could be used as a seal for cargo doors of trucks and trains or for other locks, closures, or connections requiring protection from tampering. | A tamper-evident ring is made from a split ring made of a strong resilient material and terminated by male and female fittings. The two fittings can be connected to form a continuous ring of the type that allows keys to slide entirely around the ring. One of the two fittings is breakable to prevent the ring from being reclosed and to provide a visual indication that the ring has been reopened. | 0 |
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT
Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to buckstay systems for steam generation apparatus, for example for use with large boilers that are supported by a frame.
2. Description of Related Art
Boilers are commonly constructed of tube banks forming side walls, and typically planar side walls defining a structure of polygonal and usually rectangular section. As the system reaches operating temperature, the walls expand vertically and horizontally. Additionally, furnace pressure variations, pressure differential between fireside and ambient, may produce additional flexing of the tube walls either inwardly or outwardly.
To accommodate gas pressure differential and like effects the boiler walls are typically supported on the outside by an arrangement of members that surround the boiler to provide additional support to the boiler wall and limit the deformation of the wall in a horizontal direction attributable to pressure variations. The arrangement typically uses both vertical and horizontal members that are respectively known as vertical and horizontal buckstays.
Typically, horizontal buckstays are disposed in bands around the perimeter of the boiler walls at vertically spaced intervals. Horizontal buckstays surrounding the boiler at a given level walls are mechanically tied. Thus as the boiler flexes in a horizontal direction the reaction of one buckstay is resisted by the reactions of the buckstay on the opposing wall. Vertical buckstays are provided to connect series of adjacent horizontal buckstays and complete a buckstay support structure. These may be adapted at least at some points with a connection that permits a sliding action to allow relative movement between the wall and the buckstays. As the boiler expands in a vertical direction this accommodates a variable effect on the various levels of buckstays.
The typical boiler has planar walls meeting to form corners. There is a requirement to effect a connection between horizontal buckstay members where a first wall meets a second wall at an angle to form a corner. Conventionally, horizontal buckstays are continuous elongate structural members such as I-beams spanning the length of an associated wall with buckstays associated with adjacent walls extending at the corner formed by the adjacent walls to be connected by means of corner assemblies. The corner assemblies require potentially complex arrangements of links and brackets to accommodate differential expansion between a “hot” boiler wall and “cold” buckstays. An example of such a corner assembly can be seen in FIGS. 1 and 2 .
SUMMARY OF THE INVENTION
According to the invention in a first aspect there is provided: a buckstay system for a wall of a steam generator having a first wall section which meets a second wall section at an angle to form a corner, the system comprising:
a buckstay extending generally horizontally across each wall section such as to form a connected pair at the said corner; an elongate tie bar formation extending across each wall section such as to form a fixedly mounted pair at the corner; for example by means of an end connection corner angle reinforcement tie welded at the corner to the pair of tie bars; an anchor assembly associated with each buckstay and providing engagement means by which each buckstay engages with a respective tie bar; wherein each such buckstay is split to comprise at least two rigid elongate buckstay elements mounted together to be relatively slideable in a buckstay longitudinal direction.
A pair of buckstays in accordance with the invention as most broadly stated are associated together at a corner corresponding to a point where a first boiler wall meets a second boiler wall at an angle to form a corner, the associated buckstays being dimensioned and configured for an associated boiler to support such boiler walls in familiar manner. Each buckstay extends across an associated boiler wall. Tie bars are provided in generally conventional manner, and each buckstay engages with a respective tie bar in familiar force transferring manner so that a buckstay forming part of a buckstay assembly can react to horizontal loading in the wall and tend to prevent dishing.
However, a buckstay in accordance with the invention is particularly characterised in that it is split to comprise at least two rigid elongate buckstay elements which are slideably mounted together in mechanical association in a longitudinal direction. This slideable configuration enables each buckstay, in itself, to accommodate expansion in a longitudinal (that is, in use, horizontal) direction, and in particular to accommodate differential expansion between conditions imposed by the difference between a hot boiler wall and cold buckstays. Since the buckstay itself, by being variable in length via such a mechanical means, accommodates this expansion, the requirement in the prior art to provide potentially complex arrangements of links and brackets between a pair of buckstays at each corner is reduced or eliminated.
Instead of such a complex connection, a simple connection may be provided between the horizontal extensions of each buckstay at a corner, for example in the form of a simple mechanical connection between respective formations on each buckstay which extend beyond a said corner. For example, a fixed mechanical engagement between a bracket portion on an end of a first such buckstay and a receiving portion on an end of a second such buckstay may be provided. This joint need not provide for any expansion in a buckstay longitudinal, or horizontal, direction. Optionally, the joint may be adapted to provide for a relative variation in angle between the two buckstays meeting at the joint. Alternatively, the joint may simply be fixed, for example bolted or welded.
An anchor assembly is associated with each buckstay to enable the buckstay to engage with a tie bar of its associated wall and thus enable the buckstay arrangement in use to transmit bending forces which tend to bend each wall section to each respective buckstay, which therefore resists such bending forces in generally conventional manner.
An anchor assembly for example comprises a support formation such as a plate formation fixedly engaged with, and for example welded to, a buckstay element, and a bearing surface located to bear upon and engage in use with a surface of a tie bar. A buckstay element may comprise an anchor housing, for example including a co-operably shaped recess, to receive a support formation. In a particular preferred embodiment, two rectangular support plates, comprising an upper and a lower support plate, are deployed above and below a buckstay element to comprise an anchor assembly. The support formation(s) of the anchor assembly preferably comprise additional stiffening plates, for example in a direction parallel to and/or perpendicular to a longitudinal direction of the buckstay.
To minimise loading balances, it is preferable that each anchor assembly is provided on a buckstay element closely towards a corner formed by its associated wall and the adjacent wall. For example, each buckstay anchor assembly is preferably within 2 m and more preferably within 600 mm of such a corner.
In a more complete aspect, a buckstay system is provided for a wall of a steam generator having plural wall sections which meet adjacent wall sections at an angle to form a polygonal steam generator structure, and in particular at orthogonal angles to form a rectangular-sectioned steam generator structure. The system comprises at least one buckstay assembly comprising a plurality of buckstays as above described disposed surroundingly around the plural wall sections, the assembly thereby surrounding the perimeter of the wall of the steam generator, the buckstays configured and connected in the manner above described. That is, each buckstay in the assembly comprises at least two rigid elongate buckstay elements mounted together to be relatively slideable in a buckstay longitudinal direction.
Preferably each buckstay assembly is disposed generally horizontally. Preferably a plurality of such horizontal buckstay assemblies spaced vertically up a steam generator structure are provided.
Vertical support means may be provided to support and space such plural horizontal buckstay assemblies vertically up the steam generator, for example in the form of vertical buckstays in familiar manner. Vertical buckstays may engage with horizontal buckstays by means of engagement which is fixed in a vertical direction, or which permits movement in a vertical direction for example in sliding manner. Such buckstay arrangements will be familiar.
The distinctive feature of the present invention is in the split horizontal buckstay, providing two or more buckstay elements to comprise the horizontal buckstay, with horizontal sliding engagement provided between the elements to accommodate expansion by giving the buckstay an inherent capacity to vary in length. Conveniently, vertical supports such as vertical buckstays are provided in the vicinity of some or all of the points where buckstay elements of a horizontal buckstay make sliding engagement. For example, at a sliding engagement point between two horizontal buckstay elements, a vertical support is provided having a fixed engagement with one said element, and having a sliding engagement with the other said element whereby said element may slide horizontally relative to the vertical support and therefore relative to the other element.
In the preferred embodiment, a buckstay system comprises horizontal and vertical buckstays which can embody generally familiar principles of design. The buckstay system may be restrained and the weight carried by a support frame, for example in that load carrying restraints are provided between a buckstay and a frame member at a number of horizontal restraint levels. The buckstay system is distinctly characterised in that the horizontal buckstays are split into at least two buckstay elements to accommodate horizontal expansion, most preferably by the vertical buckstays. This dispenses with the need for complex corner bracket arrangements between adjacent horizontal buckstays at a wall corner, and can also confer advantages of flexibility of design, for example in reducing the number of buckstay fixed levels which might be required compared with typical prior art structures.
A horizontal buckstay element conveniently comprises a rigid elongate structural member, for example of a suitable structural metal such as structural steel. A buckstay conveniently comprises a rolled member. A buckstay element is for example a rolled steel member. A horizontal buckstay element may for example have a web shaped surface.
A sliding engagement between two buckstay elements is made in any suitable manner that permits sliding to vary length in a buckstay elongate direction but tends to maintain the rigidity of the structure of the buckstay to resist bending forces out of this buckstay elongate direction. For example, buckstay elements may be provided with end formations which engage in side to side sliding manner, in telescoping manner etc. For example, a sliding connection between buckstay elements may be contained within a housing to maintain rigidity of the structure out of the buckstay elongate direction. In a preferred embodiment, a buckstay element is a web structure, and a sliding engagement connection is provided which permits sliding movement in a longitudinal direction of the two buckstay elements by means of relative sliding of the web surfaces.
BRIEF DESCRIPTION OF THE DRAWING
The invention will now be described by way of example only with reference to FIGS. 1 to 7 with the accompanied drawings, in which:
FIG. 1 is a plan section of a prior art horizontal buckstay assembly at a restraint level;
FIG. 2 is a more detailed section through the buckstay corner bracket arrangement of FIG. 1 ;
FIG. 3 is a plan section of a horizontal buckstay assembly according to an embodiment of the invention at a restraint level; FIG. 4 is a transverse section through and elevation of the buckstay corner region of FIG. 3 ;
FIG. 5 is a more detailed section through the buckstay anchor assembly of FIG. 4 ;
FIG. 6 is a section through B-B of FIG. 5 .
FIG. 7 is a side elevation of a boiler with a buckstay system suitable to embody the principles of the invention.
DETAILED DESCRIPTION OF THE INVENTION
An arrangement of horizontal buckstays at a restraint level in a typical prior art buckstay system is shown in FIG. 1 , with a corner assembly shown in greater detail in FIG. 2 .
Boiler walls 5 of a rectangular boiler are surrounded by an arrangement of horizontal buckstays 4 and vertical buckstays 6 . Buckstays are of any suitable known construction, for example comprising steel I beams. The arrangement in FIG. 1 is illustrated at a restraint level, and restraints are provided to transmit load to a support framework 1 .
As can be seen in particular detail in FIG. 2 , a complex arrangement of brackets and links is required to accommodate horizontal expansion as the thermal regime changes. Each horizontal buckstay 4 comprises a single monolithic elongate structural member. Each buckstay 4 is provided with an end bracket 10 which is typically welded to the web portion 12 of the I beam comprising the buckstay. Elongate tie bars 9 are provided. A corner tie 13 and corner bracket 14 are welded to a pair of adjacent tie bars 9 at a corner. A link is provided between the corner bracket 14 which is a fixed part of the tie bar system and the end bracket 10 fixed to each adjacent buckstay 4 by means of the elongate link plates 16 and pin connections 18 . The assembly is necessarily complex as it is required thereby to accommodate relative lateral movement of the respective buckstays and tiebar assembly as the conditions change between cold and hot operation.
FIG. 3 illustrates a typical plan view at a restraint level of an arrangement in accordance with an example embodiment of the invention. This shows a steel support framework comprising horizontal 20 and vertical 19 steel girders which surrounds a boiler wall 25 . Horizontal buckstays 24 surround the wall sections and provide a means of reacting to an expansion load within the boiler.
Where the arrangement differs in accordance with the invention is that a buckstay 24 does not comprise a single monolithic whole, but is instead comprised of multiple (in the example two) rigid elongate elements which are relatively slideable at a split point 27 . The result of this split is that length changes in a horizontal direction can be accommodated inherently in the horizontal buckstay 24 itself, as the sliding action varies its overall length, which can simplify corner structures as these no longer need to accommodate this.
Vertical buckstays 26 are provided in generally familiar manner. At least one, and depending on the size of the boiler more than one, vertical buckstay may be provided. Preferably, a vertical buckstay is linked to a horizontal buckstay in the vicinity of a split point 27 . For example, one of the two vertical buckstays on each long side of the illustrated in FIG. 3 , and the single vertical buckstay on each short side in FIG. 3 , are so located. Restraints 22 tie the buckstay assembly, again conveniently at these points, to the steel girders which make up the support framework.
This arrangement produces a simplification of the corner structure, which is illustrated in greater detail in FIGS. 4 to 6 .
FIG. 4 illustrates a corner portion of a buckstay assembly in accordance with the invention. A pair of horizontal buckstays 24 a , 24 b meet at a wall corner.
The direct connection between the two adjacent buckstays meeting at the corner is much simplified. A first horizontal buckstay 24 a is provided with an elongate buckstay bracket member 30 . This engages with a flange surface of a second buckstay 24 b by means of a cut away of the flange 32 in the vicinity of this bracket. A simple single pin connection 34 in the illustrated embodiment, or any other suitable simple fixed or rotating connection, is all that is needed to tie the two buckstays together at the corner.
A tie bar assembly at the corner comprises the end portions of each respective elongate main tie bar 42 or 46 to which is welded a respective stub tie bar 43 or 47 , the assembly being completed by a welded corner reinforcement angle formation 50 that completes the corner, and connects the two tie bars. Buckstays are located on and engage with the tie bar assembly via respective anchors 44 or 48 no more than 600 mm (measure by anchor centre line) inboard of the corner. Buckstay clips 49 engage with the tie bars.
The anchoring arrangement of a first anchor 44 is additionally illustrated with reference to a side elevation representing a view along A-A of FIG. 4 a as illustrated in FIG. 4 b . FIG. 4 c illustrates the use of a cheek plate 40 . This anchor formation is illustrated in greater detail in transverse sectional view FIG. 5 (with bearing plates omitted for clarity) and in section through B-B in FIG. 6 .
Engagement between the buckstay 24 b and the tie bar assembly illustrated in FIG. 4 is achieved by the anchoring means 44 , and in particular by engagement of a bearing surface 52 on the anchoring means and a bearing pad 54 at an adjacent engagement end of the stub tie bar 43 .
A horizontal buckstay 24 b is brought into a load transferring engagement with the tie bar assembly by means of a pair of anchor plates 56 to be received in an anchor housing 53 in a pair of recesses 55 located above and below the horizontal buckstay. The anchor plate comprises a plate having a 20 mm thickness, 250 mm wide. It is provided with secondary vertical 58 and horizontal 59 stiffening plates which are 10 mm in thickness. It is fixedly mounted, for example by welding, into a corresponding recess 55 so as to be in fixed relationship with the buckstay 24 b . A forward facing bearing surface 52 then makes a bearing engagement with corresponding bearing surfaces 54 on an adjacent tie bar. Thus, loads may be transmitted to the buckstay system allowing the buckstay system to react against them.
FIG. 7 illustrates an elevation of a buckstay system used in association with a boiler 61 . The buckstay system is designed to transmit transient pressure loading to the boiler support structure via a suitable restraint link system in generally familiar manner, for example as illustrated in FIG. 3 .
To that end, the buckstay system generally comprises a framework of horizontal and vertical elongate structures. Horizontal buckstays are provided at a plurality of buckstay levels as illustrated and labelled respectively L 1 to L 20 a on the left hand side of FIG. 7 . Vertical members comprising continuous O/T posts towards the corners of the boiler structure, and vertical buckstays therebetween, tie with the horizontal buckstays to complete the buckstay assembly.
These vertical buckstays are used in accordance with the invention to split horizontal buckstays which would otherwise extend in continuous manner between boiler corners. The number of vertical buckstays to be used is dependent on many factors including boiler width, depth, sootblowers etc. As a general guide, a single vertical buckstay might be appropriate for a wall width of less than 17 m, two for a wall width of up to 24 m, and three for a wall width of an excessive 24 m. Typically, the vertical buckstays will be positioned such so that they split horizontal buckstays into equal lengths.
Usually vertical buckstays will span from the first buckstay level L 1 to the transition header level 70 . Buckstays are anchored to wall via a tie bar and anchor arrangement such as described above. Tie bars may be anchored to the boiler wall in such manner as to allow the tie bar to be free to move vertically with the buckstay to provide a vertical buckstay sliding joint 67 , or may be anchored to the tube wall to allow no such vertical movement to provide for a buckstay fixed level joint 65 at a buckstay fixed level 66 .
Buckstays are linked to the supporting steelwork at the bracing levels only, labelled on the right side of the figure respectively B 1 to B 6 . Where possible, the distance between the horizontal bracing levels above the boiler knuckle is to be no greater than 12 m. The top horizontal bracing level B 1 is in line with buckstay level L 2 .
Each vertical buckstay may be anchored vertically by the horizontal buckstay closest to the mid span of the vertical buckstay. A typically maximum length of the vertical buckstay is likely to be limited by the differential expansion between the wall and the horizontal buckstay closest to the end. In the illustrated embodiment this differential expansion should not exceed 100 mm.
In the illustrated embodiment tie bars are anchored at each horizontal restraint level only.
Most of the horizontal buckstays create a support structure that extends around the perimeter of the boiler, and in particular that is required to extend around the points where two faces of the boiler connect to form a corner, for example in the manner illustrated in FIG. 3 . However, other buckstay structures can be noted in FIG. 7 , including mini buckstays 64 a on the burner centre line 71 and mini buckstays 64 b local to the arch, as will be familiar.
A further possible advantage of the design is that the number of buckstay fixed levels BFL required can be reduced relative to conventional buckstay arrays. In the illustrated embodiment, only three such fixed levels are necessary. | A buckstay system is described comprising horizontal buckstays for the walls of a steam generator, for example in plural vertically space assemblies tied with vertical buckstays, in which a buckstay extends generally horizontally across each wall such as to form a connected pair with an adjacent buckstay at each corner; an elongate tie bar formation extends across each wall such as to form a fixedly mounted pair with an adjacent tie bar formation at each corner; an anchor assembly associated with each buckstay and providing engagement means by which each buckstay engages with a respective tie bar; and each horizontal buckstay is split to comprise at least two rigid elongate buckstay elements mounted together to be relatively slideable in a buckstay longitudinal direction. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to the storing of a bit of information so that the bit can be read non-destructively, and stored in a nonvolatile manner.
Information is stored in memories in many different ways. Some memories are volatile, that is, the information is lost when the power is turned off. The present memory element is intended to compete with non-volatile core memories and plated-wire memories. In a plated wire memory, the information is stored in a permalloy (81-19 nickel-iron) coating which is plated onto a fine wire. In a core memory, the bit of information is stored in a toroid of ferrite material. In neither of these memories can the magnetic elements be integrated photolithographically with the drive electronics and decoders. Thus, these memories require much labor to build and cost is high. plated wire costs between $4.00 and $10.00 per bit. Core costs 1 to 2 cents per bit and it does not have a non-destructive readout. A new memory, the Crosstie Random Access Memory (CRAM) is currently being developed. The present memory element is intended to fit into the CRAM configuration but offer better characteristics.
Previously, the CRAM thin magnetic film was deposited on a silicon chip after the drive electronics, decoders, and amplifiers were fabricated. The permalloy film was etched into shapes which allow a crosstie-Bloch line pair to be generated in a memory element when a "one" was stored, and a "zero" was stored when the crosstie-Bloch line pair is absent.
Two conductors, insulated from each other and the permalloy film were used to generate or annihilate the crosstie-Bloch line pairs. The current in the conductors provided a magnetic field at the memory element which was localized. When a current was present in both conductors, the magnetic fields produced by each added up to a field sufficient to generate or annihilate depending on the polarity. The field produced by one conductor is insufficient to generate or annihilate, or switch the film. This type of addressing is called half-addressing, or half selecting. This is a misnomer however, because in reality two thirds of the switching field is needed in each conductor. With a small statistical distribution present for the currents, and a small statistical distribution allowed in the switching fields, the memory can be workable. The allowed distributions are shown in FIG. 1. The standard deviation, σ, for the switching field of the magnetic memory elements must be no larger than 5% of the switching field if acceptable yields are expected in the manufacture of chips. FIG. 1 shows that a σ of 15% is too large even for small memories, because some elements would be written unintentionally by the read field and not written by the write fields. The yield drops off precipitously for a σ larger than 5%. Thus, using the normal crosstie-Bloch line pair for the memory element, it is difficult to consistantly achieve a σ of less than 5%. The Bloch-line memory element of the present invention allows the 5% standard deviation to be much more readily obtained.
Accordingly, it is an object of the present invention to provide a Bloch-line memory element and a nonvolatile RAM memory using a Bloch-line memory element.
Further objects and advantages of the present invention will become apparent as the following description proceeds and features of novelty characterizing the invention will be pointed out with particularity in the claims annexed to and forming a part of the specification.
SUMMARY OF THE INVENTION
Briefly, the present invention relates to a Bloch-line memory element and a nonvolatile RAM memory using such a Bloch-line memory element. The Bloch-line memory element comprises a planar magnetic memory element having magnetic domains separated by a wall which contains a Bloch-line disposed within the individual memory element. Coincident write lines interact with the magnetic element for writing a Bloch-line to a predetermined area within the memory element. For sensing the presence or absence of a Bloch-line within the predetermined area, one write conductor and a sense line are used for determining the logic state of the particular memory element. A plurality of memory elements are disposed in an address matrix and can be selected for reading from or writing to the particular Bloch-line RAM memory element for determining or writing bits of words.
DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention reference may be had to the accompanying drawings wherein:
FIG. 1 is a graph of the statistical distribution for X-Y coincidence half-addressing.
FIGS. 2A-2D show Bloch-line dynamic nonvolatile memory elements of the present invention.
FIGS. 3A-3D shows the arrangement of the Bloch-line elements and the position and arrangement of the write and read lines.
FIG. 4 shows in cross-section the Bloch-line elements and the write-read lines taken along section 4--4 of FIG. 3.
FIG. 5 is a graph showing the magnetoresistive characteristic for the reading of the Bloch-line memory element of FIGS. 2A-2D.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made to the drawings wherein like reference numerals have been applied to like members.
The memory element of the present invention uses a Bloch-line and only a Bloch-line to store information. The crosstie is eliminated and none are present. By forcing the magnetization in a magnetic element to follow the proper directions, a Bloch-line must appear. The magnetic element is a planar film of permalloy as known in the prior art and is shown in FIGS. 2A-2D where each of FIGS. 2A-2D shows the Bloch-line 12 in a different location within the magnetic element. Many shapes 10 have been tried in various sizes ranging from 8μ across the neck 11 to 16μ. They all work but at slightly different magnetic field strengths. The magnetizationillustrated in FIGS. 2A and 2C illustrates two ground states with no field applied. If the Bloch-line 12 is on the left of the nonmagnetic conductor 14 it is considered to be a "one" as shown in FIGS. 2A and 2B. If Bloch-line 12 is on the right side or within conductor path 14, it is considered to be a "zero" as shown in FIGS. 2A and 2D, respectively.
Shape 10 has two stable states. The magnetization does not normally end up in one of these two states when the film is etched into these shapes. The elements must be initialized by applying two external fields. An arbitrarily large field (larger than 300 Oe) can be applied upward on the element and reduced to zero. The magnetization lines line up parallel to the edges with no field applied to avoid creating external fields which require energy. After the field is reduced to zero, the magnetization for the left three quarters area 18 of each element is as shown in FIGS. 2A-2D. But the magnetization is oriented wrong at the tail 20 (the right side). Thus two domains result. A second field (about 30 Oe) is then applied downward. The resulting magnetization is as shown in FIGS. 2A-2D described in the when the second field is reduced to zero. Thus two fieldsare required to initialize the memory elements. In other words, after fabrication, the chips will go through two oppositely directed fields to be initialized. After that, all fields are applied on the chip.
The shape element 10 is formed to set up the particular magnetic configuration, i.e., it is desirable to have the magnetization of each element pointing in the same clock-wise or counter clock-wise direction. The angles of the edges are important for setting up the directions of magnetization which force a Bloch-line to be present. Shape 10 is shaped similar to a ten-sided bi-directional barbed arrow head symmetrical about a longitudinal axis, having a first and second end along the longitudinal axis, one of the ends being more pointed than the other end, having a waist or neck 11 disposed approximately at the middle of the shape along the longitudinal axis, as shown, and having the sense or read line disposed between neck 11 and a blunt end 19a of shape element 10 in contrast to the more pointed end 19b.
In an alternate embodiment boundaries 19, c, d, e, and f, can be configurated into two straight lines comprising 19d, f and 19c, e for making the more pointed end 19b and thus, an 8 sided configuration. However, such configuration will take up more space on the chip than the configuration shown. Likewise, a properly shaped configuration of more than 10 sides can be devised. However, it is thought the 10 sided configuration shown in FIGS. 2A-2D to be optimal.
the read field generated in the row conductor is two thirds of the field required to move the Bloch line from its left stable position in area 18 past neck 11, to the right position in area 20. The read field changes themagnetization as shown in FIG. 2B if the element 10 was in the "one" state.If element 10 was the "zero" state, as shown in FIG. 2C, the read field just moves the Bloch-line a small distance toward the blunt boundary 21 asshown in FIG. 2D. When both write conductors 30, 32 shown in FIGS. 3A-3D are carrying currents, the field applied is 4/3 the field required to movethe Bloch line 12 through the neck or constriction 11. This would be a write operation.
Referring now to FIGS. 3A-3D there is shown the write conductors and the read conductors and their relationship with the respective shape elements 10 of FIGS. 2A-2D. All conductors are composed of conductive but nonmagnetic material. There are two write conductors, 30 and 32 which are insulated from each other and from the element 10 by insulators 34 (FIG. 4). Write line 32 runs across a row of shape elements 10, and write line 30 is a meandering shape connecting the columns of elements 10. Write line30 deviates from the straight column travel and hence the meandering, in order to be spatially coincident with line 32 in area 36. It is in area 36wherein writing is accomplished with each of the half or less than full write capability have reenforcing fields in order to write to the selectedelement 10 as determined by external address circuitry for selection of theselected element 10 within an address matrix in a RAM matrix. FIG. 4 shows the spatial relationships in cross-section of write conductors 30, 32, sense or read line 14, and one of the shape elements 10.
To read out the information, a current is passed as illustrated in FIGS. 2,3, and 4 through the row/column of memory elements. A sense or read currentis passed through conductor 14 including the selected element 10, in order to read the resistance of the row/column. A read current is then sent through write lead 32 which is obviously less than the full select currentso that the state of the selected element 10 does not change when being read. The changing electrical resistance of selected [element] element 10 [changes in the selected elements] with rotation of the magnetization due to magnetoresistive effects is shown in FIG. 5. If the magnetization is parallel to the current driven through addressed element 10 the resistanceis two to three percent higher than if the current is perpendicular to the magnetization. This is a magnetoresistance effect. Such changes in resistance are typically sensed by a Wheatstone bridge or other appropriate means. The changes in resistance are illustrated in the H-R curve shown in FIG. 5. The H-R curve shows the resistance to be expected for the situations shown in FIGS. 2A-2D which are indicated on the H-R curve as A, B, C, and D, respectively. If a "zero" was stored as in FIGS. 2C-2D, a large change in resistance ΔR results as indicated by the change in R between points C and D in FIG. 5. If a "one" was stored as in FIGS. 2A-2D, a small change occurs R occurs as indicated by the change in ΔR between points A and B in FIG. 5. About twice the signal can be obtained from these elements compared to the crosstie elements. The abruptchanges in resistance occur when the Bloch-line swiftly moves through the constriction neck 11 changing from a "one" to a "zero" or vice-versa. The memory element does not change state when it is read out since the read current is less than full select, the readout is non-destructive.
Thus, the cell or element can be written to in a dynamic manner but unlike a magnetic core memory, the readout is nondestructive and the state of theelement does not have to be rewritten into the element as is the case for amagnetic core memory.
These memory cells can be arranged in a standard address matrix as with other types of memory, static or dynamic with appropriate addressing logicin order to read or write from the memory. The disclosed cells can be produced by photolithographic techniques with metallic deposition of the appropriate conductor pattern in a manner known in the art.
While there has been illustrated and described what is at present considered to be a preferred embodiment of the present invention, it will be appreciated that numerous changes and modifications are likely to occurto those skilled in the art and it is intended in the appended claims to cover all those changes and modification which fall within the true spiritand scope of the present invention. | The present invention relates to a Bloch-line memory element and a nonvolatile RAM memory using such a Bloch-line memory element. The Bloch-line memory element comprises a planar magnetic memory element having magnetic domains separated by a wall which contains a Bloch-line disposed within the individual memory element. Coincident write lines interact with the magnetic element for writing a Bloch-line to a predetermined area within the memory element. For sensing the presence or absence of a Bloch-line within the predetermined area, one write conductor and a sense line are used for determining the logic state of the particular memory element. A plurality of memory elements are disposed in an address matrix and can be selected for reading from or writing to the particular Bloch-line RAM memory element for determining or writing bits of words. | 6 |
Background of the Invention
This invention relates to processing of thin semiconductor wafers such as slices of semiconductor silicon and, more particularly, to an improved method and apparatus for polishing wafers having uniform flatness of the polished surface, the improved polished wafer flatness is achieved through finite temperature control of the polishing environment. Finite polishing temperature control is made possible by providing a substantially constant thermal polishing environment wherein variation of pressure upon the polishing environment permits immediate temperature control. Timely and finite temperature control of the polishing environment also reduces the amount of thermal and mechanical bow found in such apparatus, for example, the turntable which is internally cooled. Wafer flatness as a result of polishing is also dependent upon contact surface profile of the wafers and the pressure plate in contact with the polishing surface which is supported by the turntable; thus, responsive and timely temperature control tuning plays a significant role in the polishing of semiconductor wafers.
Modern chemical-mechanical semiconductor polishing processes are typically carried out on equipment where the wafers are secured to a carrier plate by a mounting medium with the wafers having a load or pressure applied to the carrier and to the wafers by a pressure plate so as to press the wafers into frictional contact with a polishing pad mounted on a rotating turntable. The carrier and pressure plate also rotate as a result of either the driving friction from the turntable or rotation drive means directly attached to the pressure plate. Frictional heat generated at the wafer surface enhances the chemical action of the polishing fluid and thus increases the polishing rate. The polishing rate being a function of temperature stresses the importance of achieving immediate and exact temperature control of the polishing environment. Polishing fluids suitable for use in the present invention are disclosed and claimed in Walsh et al., U.S. Pat. No. 3,170,273.
Increased electronics industry demands for polished semiconductor wafers have promoted need for faster polishing rates requiring sizeable loads and substantial power input on polishing apparatus. This increased power input appears as frictional heat at the wafer polishing surface. In order to prevent excessive temperature buildup, heat is removed from the system by cooling the turntable. A typical turntable cooling system consists of a co-axial cooling water inlet and outlet through a turntable shaft along with cooling channels inside the turntable having appropriate baffles in order to prevent bypassing between inlet and outlet. However, it has been found that such an apparatus is not sufficient for temperature control under modern polishing requirements, i.e. the need for instantaneous temperature adjustment. The known methods of internally cooling the turntable do not provide quick or suitable temperature differential gradients since cooling fluid supply or volume are constant and the temperature of said fluid cannot be adjusted quickly nor can the temperature of the turntable be adjusted in a quick and precise manner through cooling means only. No matter the improved systems, temperature differences within the polishing environment result in thermal expansion differentials causing the turntable surface to deflect toward the cooled surface from the axis of rotation to the outside edge. Such thermal bowing is controllable and can be managed without flatness interference of the finished product if the temperature gradient within the turntable is carefully controlled within close tolerances.
A unique system has been developed through the operation of this invention for temperature control of semiconductor wafer polishing apparatus or other similar polishing apparatus wherein the system provides a turntable cooling water supply temperature which is maintained at a substantially constant temperature and relies on temperature control through the variation of polishing environment pressure. Polishing pad temperature control is achieved by fast response, closed loop control system which varies the polishing pressure as necessary to hold the pad temperature constant. Because of this dual temperature control system, i.e. the constant cooling of the turntable and the polishing pad temperature control, a constant temperature is maintained on both top and bottom surfaces of the turntable which results in a constant level of thermal distortion or bow. This phenomenon can then be compensated readily by generating a constant level of matching bow in the wafer carrier plate. By comparison, prior art methods usually control polishing pad temperature by varying the flow rate of the turntable cooling water. This process provides a system which responds much more slowly to thermal needs and gives less precise temperature control to the polishing environment. More importantly, however, varying the coolant flow rate changes the delta or thermal gradient across the turntable and changes its thermal distortion making it impossible to optimumly compensate for the turntable distortions by using a constant distortion of the carrier plate.
The wafer carrier is thermally insulated from the pressure plate by a resilient pressure pad. Therefore, the carrier approaches thermal equilibrium at a substantially uniform temperature and remains flat. The difference which is encountered between the plane defined by the wafers and the thermal bowed surface of the turntable can be compensated by geometric means in order to avoid excessive stock removal toward the center of the carrier causing non-uniform wafer thickness and poor flatness. Recent technological advances have enhanced methods of mounting the semiconductor wafers to the carrier plate which allow the wafers to be subjected to operations including washing, lapping, polishing and the like without mechanical distortion or unflatness of the polishing wafer. Such methodologies and apparatus have been disclosed and claimed by the invention presented in the recent Walsh U.S. applications, Ser. No. 126,807 entitled "Method and Apparatus For Wax Mounting of Thin Wafers for Polishing" now U.S. Pat. No. 4,316,757; and Ser. No. 134,714 entitled "Method and Apparatus For Improving Flatness of Polished Wafers" now U.S. Pat. No. 4,313,284.
The corrections as shown by the Walsh mounting methods are of assistance in achieving uniform polished flatness of semiconductor wafers; however, modern requirements of the semiconductor industry regarding polished silicon wafers cannot tolerate even the smallest surface flatness variations. The difficulties encountered in mounting of the wafers and accommodating the thermodynamic bowing of mechanical apparatus require additional technical input such as instantaneous and sensitive polishing environment temperature control means. Control means which rely upon fluid cooling variation either in temperature or in volume do not afford the timely or sensitivity temperature control that is necessary in order to achieve a stable geometric polishing wafer to polishing pad planar relationship. Accommodations for the bow as well as for the loading of the wafers during polishing must be made. In the manufacture of VLSI circuits, a high density of the circuit elements must be created on a silicon wafer requiring an extraordinarily high order of precision and resolution calling for wafer flatness heretofore not required. The necessary polished wafer flatness for such applications, for example, less than about 2 micrometers peak to valley, cannot be achieved at high polishing rates if the carrier mounted wafers are polished in an environment having sluggish temperature control which can be adjusted only through slow thermal adjustments of cooling fluids.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a method for improving polished wafer flatness through maintaining a turntable thermal distortion constant through constant cooling fluid temperature and flow rate in combination with constant polishing temperature achieved through pressure control means.
It is another object of the present invention to provide a method for quick response, closed loop control systems for polishing environment through constant monitoring of the polishing environment temperature.
It is a further object of the present invention to provide a method of the character stated permitting polishing of wafers to an extraordinarily high degree of flatness, which is conducive to the manufacture of VLSI circuits.
It is a still further object of the present invention to provide a method of the character stated which can be practiced simply and easily within the context of large scale, mass production manufacture and polishing of monocrystal silicon wafers and the like.
It is another object of the invention to provide a method of the character stated which can be practiced with a minimum of manual steps and which is amenable to automation.
It is a further object of the invention to provide apparatus which affords dual temperature control polishing at a constant temperature maintainable on both the top and bottom surfaces of the turntable which results in a constant level of thermal distortion which is compensatable by generating a constant level of matching bow in the wafer carrier plate.
Other objects and features of the invention will be in part apparent and in part pointed out hereinbelow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of prior art apparatus, illustrated in cross section, for carrying out a method for polishing wafers mounted on a carrier and pressure plate combination against a rotating turntable mounted polishing head. The apparatus as illustrated in FIG. 1 is representative of the prior art.
FIG. 2 is a schematic illustration of the apparatus according to the invention for carrying out the temperature control methodology for polishing wafers mounted on a carrier and pressure plate combination against an internally cooled rotating turntable mounted polishing head.
Correspondingly, reference characters indicate corresponding parts throughout the views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, current chemical-mechanical polishing processes for silicon and other semiconductor wafers are typically carried out on equipment as illustrated in FIG. 1. The wafers 1 are secured to the carrier 5 through mounting medium 3 which may be either a wax or any of several waxless mounting media which provide wafers with a friction, surface tension or other means for adhering to the carrier 5. The carrier is mounted through resilient pressure pad 7 means to pressure plate 9 which is suitably mounted to a spindle 13 through bearing mechanism 11, the spindle 13 and bearing 11 supporting a load 15 which is exerted against the pressure plate 9 and finally against wafers 1 when said wafers are in rotable contact with polishing pad 19 during operation, for example, when turntable 21 is rotating, thus forcing the rotation of the carrier 5 through friction means or independent drive means. The turntable 21 is rotated around shaft 25 which includes cooling water exit 27 and inlet 29 in communication with the hollow chamber inside the turntable, the chamber supporting the separation of the two streams through baffle 23.
The greater polishing rates required today introduce increased loads and substantial power input into the polishing methodology. This increased speed and higher input appear as frictional heat at the wafer surface during polishing. In order to prevent excessive buildup, heat is removed from the system by cooling of the turntable as illustrated in FIGS. 1 and 2. When polishing silicon wafers with apparatus of the type illustrated in FIG. 1, it has been found that the stock removal is not uniform across the surfaces of the wafers mounted on the carrier but is greater toward the center of the carrier and less toward the outside edge of the carrier. This results in a general tapering of the wafers in the radial direction from the center of the carrier. It is not uncommon to encounter radial taper readings up to 15 micrometers on larger wafer sizes. Modern semiconductor technology has increased demand for larger diameter silicon wafers; therefore, the radial taper deficiency is further exaggerated by these diameter enlargements. Wafers with significant radial taper have relatively poor flatness; thus creating a serious problem for LSI and VLSI wafer applications.
The radial taper problem is substantially the result of distortion of the turntable from a flat surface or planar surface to an upwardly convex surface resulting from thermal and mechanical stress. Distortion is substantially caused by the heat flow from the wafer 1 surfaces to the cooling water which causes the top of the turntable to be at a higher temperature than the bottom surface which is essentially at the cooling water temperature. This temperature difference results in a thermal expansion differential causing the turntable surface and polishing pad 19 mounted thereon to deflect downward at the outside edge. The carrier 5 is thermally insulated from pressure plate 9 by resilient pressure pad 7. Various methodologies would have influence on resolving these problems, for example, such as partially eliminating the problem through reduction of the polishing rate, thus the heat flux until distortion is tolerable. However, such reduction of rate would greatly reduce the wafer throughput of the polishing apparatus and therefore increase wafer polishing costs.
A more economical solution is achieved through adjusting the geometry of the polishing environment to the necessary polishing rate and thermal bow of the turntable. These adjustments are very fine tuned and require instantaneous temperature control as well as finite temperature adjustment which is achieved through variation of the load or pressure upon the wafer polishing environment. FIG. 2, the unique system according to the invention for temperature control of the wafer polishing environment, provides a turntable 21 having cooling water supplied at a substantially constant temperature. The constant temperature water supply can be maintained at any level which will fit apparatus equipment for maintaining equipment warm or in operating condition when in fact operations are interrupted. The constant temperature water source allows for immediate use of equipment without warmup time and also provides instantaneous satisfactory use of the environment when the constant water temperature control is coordinated with the pressure temperature control as illustrated in FIG. 2 through utilization of infra red (IR) pad temperature sensor 33 which is in communication with temperature controller 35, current/pressure transducer 37 and ratio relay 39. These various closed loop controller elements communicate with piston means 41 in combination with load bearing lever 43 which completes the closed loop of electromechanical apparatus and methodology for instantaneously measuring and adjusting the wafer polishing environment temperature through load or pressure means.
The dual temperature control mechanism of the present invention allows the use of an elevated cooling fluid temperature which reduces the gradient between the top and bottom surfaces of the turntable and therefore reduces the bowing or thermal distortion. The reduced bowing simplifies the problem of flatness compensation which is achieved by creating a matching distortion of the wafer carrier plate.
According to the invention, polishing pad temperature control, i.e. wafer polishing environment temperature control, is achieved by immediate responsive closed loop control systems which varies the polishing pressure as necessary to hold the pad temperature, as measured by I.R. sensor 31, constant. Because of this dual temperature control system a constant temperature is maintained on both the top and bottom surfaces of the turntable which results in a constant level of thermal distortion. This can be compensated readily by generating a constant level of matching bow on the wafer carrier plate.
By comparison, prior art methods usually control polishing pad temperature by varying the flow rate of the turntable cooling water. This is a slower response system which gives less precise control. More importantly, however, varying the coolant flow rate changes the temperature gradient across the turntable and thus changes the thermal distortion, making it impossible to optimally compensate for the turntable distortion by using a constant distortion of the carrier plate.
Use requirements of the methodology and apparatus according to the invention could require a fluid coolant, water at an ambient temperature of about 34° C. for polishing of silicon wafers. Substantially constant water coolant temperature, within plus or minus 1.0° C., would be suitable for utilizing the merits of the dual polishing environment temperature control. The invention allows use of turntable 21 cooling as the major frictional heat sink while providing fine tuning of the temperature control through the closed loop assembly. The assembly functioning through electromechanical means for correcting temperature changes by positive or negative pressure movement of the pressure plate assembly relative to the rotatable turntable assembly supported polishing pad.
The silicon wafer utilization of the methodology and apparatus according to the invention could, for example, introduce cooling water at a warm ambient temperature of 34° C. and release water through cooling fluid exit 27 from the turntable cooling chamber 31 at approximately 37° C. The inventive methodology and apparatus provide water or other cooling fluids to the turntable fluid chamber 31 in such quantities as to not exceed an entry and exit temperature differential greater than about 6° C. Under such operation conditions, the i.r. radiation pyrometer 33 would transmit a signal of from 4 to 20 ma to the temperature controller 35 which would also provide a 4 to 20 ma signal to current/pressure transducer 37 which would provide a 3 to 15 psi output to the air pressure ratio relay 39. The ratio relay 39 would magnify the control signal pressure by a factor, for example, of 3 thereby providing a 9 to 45 psi pneumatic pressure to the piston means 41 which is in communication with pressure plate 9 through lever 43. In general, the inventive apparatus is capable of producing immediate pressure variation on the pressure plate mounted wafers of from about 1 to about 100 psi or greater. The foregoing represents a typical utilization of the invention for the polishing of silicon wafers utilizing the fine tuning temperature control, closed loop assembly and process according to the invention.
Although the foregoing includes a discussion of a possible use mode contemplated for carrying out the invention, various modifications can be made and still be within the spirit and scope of the inventive disclosure.
As various modifications can be made in the method and construction herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings, shall be interpreted as illustrative rather than limiting. | A wafer workpiece polishing temperature control method and apparatus are provided wherein wafers are mounted upon a rotatable pressure plate assembly positioned in rotatable contact with a turntable assembly supported polishing pad, the turntable assembly having internal fluid cooling means, the wafer polishing temperature control being achieved through responsive closed loop electromechanical means activated by variation of polishing pressure upon the wafers and the polishing pad. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This disclosure claims the benefit of priority to U.S. Provisional Patent Application No. 62/047,280, filed 8 Sep., 2014, the disclosure of which is incorporated herein in its entirety.
FIELD OF THE INVENTION
[0002] The herein disclosed invention is directed to protective inorganic coatings for aluminum and aluminum oxides.
BACKGROUND
[0003] The electrochemical formation of oxide layers on aluminum is a well-known and widely used industrial procedure to produce protective and/or decorative coatings on aluminum and/or aluminum alloys. Electrolytically produced aluminum oxide layers protect the base metal from corrosion and weathering and furthermore may increase the surface hardness and the abrasive resistance of the aluminum part.
[0004] Many different processes of anodizing are known. For example, aluminum materials can be anodized in electrolytes such as sulfuric acid, chromic acid, phosphoric acid, and oxalic acid by the application of AC or DC currents at a bath temperature of 10-25° C. Variations in this treatment can change the thicknesses and/or hardness of the anodized aluminum oxide layer.
[0005] The porosity of the anodized layer may be favorable for the adhesion of organic coatings, but exhibits a major drawback, namely the lack of protection against corrosive media. Therefore, and to impart maximum corrosion stability, anodized aluminum layers are often sealed in a subsequent process step. During sealing, which might be a hot sealing and/or cold sealing process, the aluminum oxide becomes hydrated and is transformed from its amorphous, essentially water-free constitution to a boehmite structure. This transformation is accompanied by a volume expansion or swelling of the oxide that in turn procures the sealing of the porous structure. Hot sealing of the anodized layer is usually performed in hot water or in steam, whereas the cold sealing process is operated at temperatures close to 30° C. in the presence of nickel fluoride. Sealing improves the corrosion resistance and resistance to weathering of anodized aluminum parts in a pH range from 5-8.
[0006] Unfortunately, sealed anodized aluminum surfaces continue to display poor corrosion resistance and stability below pH 4 and/or above pH 9. Additional seals or coatings have been attempted but improved coatings with stability to high and low pH, accelerated corrosion testing, abrasion, and fogging are needed.
SUMMARY
[0007] Herein is disclosed a layered product that includes an aluminum oxide layer having a composition that is free of silicates; and a silicate glass layer directly carried by the aluminum oxide layer and having a silicate glass layer EDX composition that consists of silicon, oxygen, sodium, optionally lithium, and optionally boron; wherein the silicate glass layer EDX composition is free of aluminum.
[0008] Additionally disclosed is a process for preparing a surface coating that includes forming a coated-aluminum-oxide layer by applying an aqueous silicate solution to an aluminum oxide layer having a thickness of about 1 μm to about 25 μm, the aluminum oxide layer consisting of a sealed, anodized-aluminum layer or a hydrated PVD alumina layer, the aqueous silicate solution having a pH of about 11 to about 13, a composition that includes a ratio of SiO 2 to M 2 O of about 3.5 to about 2, where M is selected from Li, Na, K, and a mixture thereof, and a ratio of SiO 2 to B 2 O 3 of about 10:1 to about 200:1; and thereafter, polymerizing and curing a silicate glass on the sealed, anodized-aluminum layer by (A) heating the coated, anodized-aluminum layer to a temperature of about 200° C. to about 500° C. or (B) exposing the coated, anodized-aluminum layer to an infrared source.
BRIEF DESCRIPTION OF THE FIGURES
[0009] For a more complete understanding of the disclosure, reference should be made to the following detailed description and accompanying drawing figures wherein:
[0010] FIG. 1 is a plot of the average atomic percentages of silicon and aluminum as a function of distance from the surface of a comparative product as calculated from EDX;
[0011] FIG. 2 is a plot of the average atomic percentages of silicon and aluminum as a function of distance from the surface of a herein-described product as calculated from EDX;
[0012] FIG. 3 is a comparison between silicon atomic percentages in the aluminum oxide layer of a comparative sample ( FIG. 1 ) and a herein-described product ( FIG. 2 );
[0013] FIG. 4 is a plot of ion counts as a function of distance as determined by TOF-SIMS for a comparative product, where milling began at the surface (T=0);
[0014] FIG. 5 is a plot of ion counts as a function of distance as determined by TOF-SIMS for a herein-described sample, where milling began at the surface (T=0);
[0015] FIG. 6 is a photograph of a comparative product (prior art sample) (bottom) and a herein-described sample (top) after a 24 h CASS test;
[0016] FIG. 7 is a photograph of a partially coated sample after heating to 280° C. for 15 minutes, the photograph (Left) showing cracking and/or crazing of an uncoated sealed anodized aluminum layer and (Right) showing the undamaged coated section.
[0017] While specific embodiments are illustrated in the figures, with the understanding that the disclosure is intended to be illustrative, these embodiments are not intended to limit the invention described and illustrated herein.
DETAILED DESCRIPTION
[0018] The present disclosure is directed to processes for manufacturing and to metal products that demonstrate excellent durability and ease of preparation. In general, a product includes a metal or metal alloy substrate, an oxide layer on the surface of the metal or metal alloy substrate, and a glass layer on the oxide layer that is a silicate or borosilicate glass. The product according to this invention may be used in interior/exterior applications such as architectural fixtures, automobile parts, aerospace parts, marine components, bicycle components, motor bike parts, heavy transport vehicle parts (including truck, train, and rail), military related components, mirrors, streetscape components (e.g., street lights and exterior signs), furniture, appliances (e.g., refrigerators, washing machine, clothing driers, dishwashers, range, table top appliances (e.g., mixers, blenders, toasters, rice makers)), solar power components (e.g., reflectors, and collectors), consumer products and related parts (e.g., cell phones, and computer components), heat exchanges, medical instruments and tools, and/or oil and gas production components (e.g., coil tubing); wherein the substrate is generally considered the fixture or part and the oxide layer and silicate glass coat the fixture or part. Architectural fixtures and parts include material for or items selected from window frames, window trim, doors, claddings, mirrors, reflectors, lamp housings, hinges, handles, furniture parts including table or chair legs, seats or tops, brackets, tracks, railings, and/or hardware. Automobile parts include members of vehicle bodies and/or vehicle wheels; including, for example, roof racks/rails, window trim, waste finisher, step/side bars, door trim, lamp trim, door handles, exhaust manifolds, reflectors, fuel cap flaps, spoilers, pillar covers, door handle anti-scratch plates, antenna, brandings/emblems, window visors, speaker trim, hub caps, wheel rims, lug nuts, engine parts (e.g., pistons, blocks, shafts, cams, pulleys, housings, and covers), and/or exhaust parts (e.g., exhaust tubing/piping, mufflers, converter covers, clamps, hangers, and tail pipes). Aerospace parts include, for example, engine covers, panels, spinners, propellers, wings, flaps, elevators, and cowlings. Marine components include, for example, hulls, masts, booms, pulleys, winch, tiller, spreaders, grabrail, turnbuckle, stanchion, hatch trim, and/or trailers. Bicycle components include, for example, frames, posts, tubes, handle bars, rims, levers, gears, and/or hubs. Motor bike parts include, for example, wheels, suspension tubes, swinging arms, engine parts, exhaust parts, and trim.
[0019] Herein is disclosed a layered product that includes an aluminum oxide layer having a composition that is free of silicates, preferably having an aluminum oxide layer EDX composition that is free of silicon, boron, and/or nickel; and a silicate glass layer directly carried by the aluminum oxide layer and having a silicate glass layer EDX composition that consists of silicon, oxygen, sodium, optionally lithium, and optionally boron; wherein the silicate glass layer EDX composition is free of aluminum. The silicate glass layer has a composition that includes about 55 wt. % to about 98 wt. % SiO 2 , 0 wt. % to about 6.7 wt. % B 2 O 3 , and about 2.3 wt. % to about 36 wt. % M 2 O, wherein M is selected from the group consisting of lithium, sodium, potassium, and a mixture thereof; preferably wherein M is a mixture of Li and Na, for example with a Li:Na ratio of about 1:10 to 10:1; wherein the silicate glass layer includes less than 0.1 wt. % aluminum, preferably less than 0.01 wt. % aluminum, even more preferably less than 0.001 wt. % aluminum. Preferably, the silicate glass layer has a TOF-SIMS composition that consists of silicon, oxygen, sodium, optionally lithium, and optionally boron; wherein silicate glass layer TOF-SIMS data may show a trace amount of aluminum. The silicate glass layer can have a thickness in the range of about 50 nm to about 3000 nm, about 50 nm to about 2000 nm, about 50 nm to about 1500 nm, about 100 nm to about 1500 nm, about 250 nm to about 1500 nm, or about 500 nm to about 1000 nm.
[0020] The herein disclosed aluminum oxide layer is, preferably, free of silicates. That is, the aluminum oxide layer does not include glass forming silicone oxides (e.g., SiO 2 ), aluminosilicate, borosilicates, or mixtures thereof. In one instance, the aluminum oxide layer has an EDX composition that consists of aluminum, oxygen, sulfur, and an optional colorant; and/or a TOF-SIMS composition that consists of aluminum, oxygen, sulfur, and an optional colorant. Preferably, the aluminum oxide layer TOF-SIMS composition is free of silicon.
[0021] In one instance, the aluminum oxide layer is a sealed aluminum oxide layer or a PVD aluminum oxide layer (or hydrated PVD aluminum oxide layer). In still another instance, the layered product includes an aluminum surface; wherein the aluminum oxide layer is directly attached to the aluminum surface. Preferably, the layered product still further includes a substrate, carrying the aluminum oxide layer, selected from the group consisting of aluminum, an aluminum alloy, and stainless steel.
[0022] Preferably, the layered product is free of an aluminosilicate or silicate/alumina interdiffusion. Even more preferably, the layered product passes both a 2 minute “pH 14 Test” and a “24-hour CASS Test”.
[0023] Further disclosed is a coated product that includes an aluminum surface directly attached to a barrier layer. This barrier layer is directly attached to an aluminum oxide layer which is directly attached to a silicate glass layer. Herein, “directly attached” signifies and means that the denoted layers are chemically and/or physically bonded without an intervening layer. This absence of an intervening layer can be determined by spectroscopic and/or microscopic methods, for example, energy-dispersive X-ray (EDX) spectroscopy, time-of-flight secondary ion mass spectroscopy (TOF-SIMS), and/or scanning electron microscopy (SEM). Still further disclosed is a corrosion resistant coating that includes an aluminum oxide layer attached to a substrate, where the aluminum oxide layer can have a composition that includes, for example, about 70 wt. % to about 90 wt. % Al 2 O 3 , about 2.5 wt. % to about 7.5 wt. % H 2 O, and about 10 wt. % to about 20 wt. % SO 3 . The corrosion resistant coating can include a borosilicate glass directly attached to the aluminum oxide layer, wherein the borosilicate glass has a composition that includes SiO 2 , B 2 O 3 , and M 2 O. M 2 O is an alkali metal oxide where M is selected from the group consisting of Li, Na, K, and a mixture thereof (e.g., Na 2 O, Li 2 O, LiNaO, K 2 O). Notably, the components of the borosilicate glass (SiO 2 , B 2 O 3 , and M 2 O) are not distinct but are part of and, preferably, homogeneously distributed throughout the glass. That is, the silicate glass layer and the aluminum oxide layer compositions are described based on recognizable components (e.g., SiO 2 , B 2 O 3 , Al 2 O 3 ) in the layers but consists of or comprise homogeneous compositions.
[0024] The composition of the silicate glass layer, based on the materials used to prepare the layer, can include about 55 wt. % to about 98 wt. % SiO 2 , 0 wt. % to about 6.7 wt. % B 2 O 3 , and about 2.3 wt. % to about 36 wt. % M 2 O. Notably, M is selected from the group consisting of lithium, sodium, potassium, and a mixture thereof and this selection can significantly affect the weight percentages of the component parts. For example in a composition wherein the molar ratio of the components are held constant, the variation of M 2 O from one hundred percent lithium, with an atomic mass of 6.941, to one hundred percent potassium, with an atomic mass of 39.098, causes a ten-fold change in the weight percentages. A preferably description of the composition of the silicate glass layer is based on molar ratios of the components, yet such a description is not common in the art. Preferably, the molar ratios of the components (expressed as percentages) are about 67% to about 81% SiO 2 , 0% to about 7% B 2 O 3 , and about 17% to about 28% M 2 O. Alternatively, the molar ratios can be about 75% to about 80% SiO 2 , and about 20% to about 25% M 2 O; or about 67% to about 76% SiO 2 , about 3% to about 5% B 2 O 3 , and about 19% to about 30% M 2 O.
[0025] The silicate glass layer can have an “EDX composition” which is the silicate glass layer composition as determined by EDX spectroscopy (see FIG. 2 ). Preferably, the silicate glass layer EDX composition includes silicon, oxygen and sodium. More preferably, the silicate glass layer EDX composition consists of silicon, oxygen, and elements selected from the group consisting of sodium, lithium, potassium, boron, and mixtures thereof. In various aspects, the silicate glass layer EDX composition can consist of silicon, oxygen, sodium, and boron; silicon, oxygen, lithium, and boron; silicon, oxygen, sodium, and lithium; silicon, oxygen, sodium, lithium, and boron; or silicon, oxygen, sodium, lithium, potassium, and boron. In examples where the silicate glass composition (as determined by EDX or other methods) includes boron, the silicate glass is also described as a borosilicate glass. The silicate glass layer EDX composition can further be described as consisting of silicon, oxygen, sodium, optionally lithium, and optionally boron. In some aspects, the silicate glass layer may be described as consisting of silicon, oxygen, optionally boron, sodium, and optionally lithium but may include trace amounts of potassium due to materials employed for the production of the silicate glass layer having slight impurities. Notably, the silicate glass layer may in fact include hydrogen but hydrogen is not observable by EDX spectroscopy. More preferably, the silicate glass layer EDX composition is free of aluminum.
[0026] The silicate glass layer can have a “TOF-SIMS composition” which is the silicate glass layer composition as determined by TOF-SIMS (see FIG. 5 ). Preferably, the silicate glass layer TOF-SIMS composition includes silicon, oxygen, and sodium. More preferably, the silicate glass layer TOF-SIMS composition consists of silicon, oxygen and elements selected from the group consisting of sodium, lithium, potassium, boron, and mixtures thereof. Notably, the silicate glass layer may include hydrogen but is not determined due to experimental difficulties and sample preparation variations. Additionally and due to the extremely high sensitivity of TOF-SIMS, the silicate glass layer TOF-SIMS composition may appear to include trace amounts of aluminum. Preferably, the silicate glass layer includes less than 0.1 wt. % aluminum, preferably less than 0.01 wt. % aluminum, even more preferably less than 0.001 wt. % aluminum.
[0027] When the silicate glass layer includes both sodium and lithium, the silicate glass layer has a Na:Li atom ratio that is preferably about 1:9 to about 9:1. More preferably, the Na:Li atom ratio is about 1:5 to about 5:1; even more preferably, about 1:2.5 to about 2.5:1.
[0028] When the silicate glass layer is a borosilicate glass layer, that is when the silicate glass layer includes boron, the silicate glass layer has a Si/B atom ratio that is, preferably, about 10:1 to about 200:1. More preferably, the Si/B ratio is about 10:1 to about 100:1; even more preferably about 25:1 to about 100:1.
[0029] The silicate glass layer can have a thickness of about 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1000 nm, 1500 nm, 2000 nm, 2500 nm, or 3000 nm. Alternatively, the silicate glass layer thickness can be in the range of about 50 nm to about 3000 nm, about 50 nm to about 2000 nm, about 50 nm to about 1500 nm, about 100 nm to about 1500 nm, about 250 nm to about 1500 nm, or about 500 nm to about 1000 nm.
[0030] In another example, the silicate glass layer includes a mixture of alkali metals selected from a mixture of sodium and potassium; sodium, lithium and potassium; and lithium and potassium. That is, in this example the silicate glass layer includes a mixture of alkali metals wherein one alkali metal is potassium. Preferably, the silicate glass layer includes a non-homogenous distribution of potassium. For example, wherein the silicate glass layer includes a high-potassium region near the surface (away from the aluminum oxide layer), as compared to a lower-potassium concentration in a region of the silicate glass adjacent to the substrate. That is, the silicate glass can include a plurality of regions as differentiated by the depth profile of the potassium concentration.
[0031] Preferably, the concentration of the silicon in the silicate glass layer is consistent across and through the layer. The consistency of the composition can be determined from the silicon concentration in the silicate glass layer EDX composition, preferably the silicon concentration varies by less than 5%, 4%, 3%, 2%, or 1% across and through the silicon glass layer. Additionally, the concentration of oxygen in the silicate glass layer is, preferably, consistent across and through the layer. That is, the oxygen concentration in the silicate glass layer EDX composition, preferably, varies by less than 5%, 4%, 3%, 2%, or 1% across and through the silicate glass layer.
[0032] The silicate glass layer is preferably a dense, impermeable layer. More preferably, the silicate glass layer is non-porous. Even more preferably, the silicate glass layer is a transparent, amorphous solid.
[0033] As described above, the aluminum oxide layer can include about 70 wt. % to about 90 wt. % Al 2 O 3 , about 2.5 wt. % to about 7.5 wt. % H 2 O, and about 10 wt. % to about 20 wt. % SO 3 ; about 75 wt. % to about 85 wt. % Al 2 O 3 , about 3.5 wt. % to about 5.5 wt. % H 2 O, and about 12.5 wt. % to about 17.5 wt. % SO 3 ; or about 80-81 wt. % Al 2 O 3 , about 5-6 wt. % H 2 O, and 14-15 wt. % SO 3 . In alternative examples, the aluminum oxide layer can be free of SO 3 . In one particularly preferable example, the aluminum oxide layer has an EDX composition that consists of aluminum, oxygen, sulfur, and an optional colorant. Even more preferably, the aluminum oxide layer EDX composition is free of silicon, the aluminum oxide layer EDX composition is free of nickel, the aluminum oxide layer EDX composition is free of silicon and nickel, and/or the aluminum oxide layer EDX composition is free of silicon, boron, and nickel.
[0034] Preferably, the composition of the aluminum oxide layer is consistent across and through the layer. The consistency of the composition can be determined from the aluminum concentration in the aluminum oxide layer EDX composition, preferably the aluminum concentration varies by less than 5%, 4%, 3%, 2%, or 1% across and through the aluminum oxide layer. The consistency of the composition can also be determined from the oxygen concentration in the aluminum oxide layer EDX composition, preferably the oxygen concentration varies by less than 5%, 4%, 3%, 2%, or 1% across and through the aluminum oxide layer. In examples wherein a dye is added to the aluminum oxide layer during manufacturing, the composition may vary through the layer depth due to localization of the dye in aluminum oxide pores.
[0035] The aluminum oxide layer EDX composition can include or, preferably, consists of 31-36% aluminum, 60-70% oxygen, and 2-5% sulfur; more preferably, 31-35% aluminum, 63-67% oxygen, and 3-4% sulfur; and even more preferably, 32-34% aluminum, 64-66% oxygen, and 3-3.5% sulfur. As described above, hydrogen concentrations are not available from EDX spectroscopy and therefore are not part of the EDX composition. Additionally, the aluminum oxide layer EDX composition can include an aluminum:oxygen ratio of about 1:2.
[0036] The aluminum oxide layer TOF-SIMS composition includes aluminum and oxygen. In one example, the aluminum oxide layer TOF-SIMS composition includes or, preferably, consists of aluminum, oxygen, sulfur, and an optional colorant. More preferably, the aluminum oxide layer TOF-SIMS composition is free of silicon, or free of silicon and boron (see FIG. 5 ). In some examples, the aluminum oxide layer TOF-SIMS composition includes sodium and/or lithium but, preferably, is substantially free of, or is free of, potassium. Notably, experimental conditions may make the observation of one or more atoms in the TOF-SIMS analysis difficult to identify—for example, the O+ mass/ion was infrequently observed at 16 amu but readily observable as the Cs ion pair, CsO+, a result of Cs ion milling.
[0037] The aluminum oxide layer can have a thickness of less than about 50 microns, 40 microns, 30 microns, 25 microns, 20 microns, 10 microns, 5 microns, 4 microns, 3 microns, 2 microns, 1 micron, or 500 nm. Preferably, the aluminum oxide thickness is a range of about 1 to about 30 microns, about 2 to about 25 microns, about 3 to about 20 microns, or about 5 to about 25 microns. In one particular example, the aluminum oxide layer has a thickness less than about 10 microns and the borosilicate glass has a thickness less than about 1 micron.
[0038] The aluminum oxide layer can include a boehmite/bayerite region without deviating from the compositional ranges provided above. Notably, the boehmite/bayerite region includes a hydrated aluminum oxide, that is, an aluminum oxide with a higher proportion of hydroxyl groups than a dehydrated Al 2 O 3 . For example, the boehmite/bayerite region includes AlO(OH) and/or Al(OH) 3 groups. In examples with the boehmite/bayerite region, the boehmite/bayerite region is directly attached to the silicate glass layer. In one example, the boehmite/bayerite region is within the aluminum oxide layer, with a higher proportion of hydroxyl groups, and is positioned between a region with a lower proportion of hydroxyl groups and the silicate glass layer. In another example, the boehmite/bayerite region extends through the entire aluminum oxide layer. The boehmite/bayerite region may be identified in TOF-SIMS plots of aluminum counts over time (depth) (see FIG. 5 ). Without being bound to theory, variation in aluminum counts at or near the silicate glass layer can be due to an increased friability of the boehmite/bayerite region compared to the majority of the aluminum oxide layer. This variation, as shown in FIG. 5 as seen between milling times of about 1300 and 2000, is believed to be or is indicative of the boehmite/bayerite region.
[0039] As noted above, this composition can include a barrier layer directly attached to the aluminum oxide layer. Preferably, the barrier layer has a TOF-SIMS composition that includes aluminum and oxygen. In some examples, the barrier layer TOF-SIMS composition further includes sodium and/or lithium. In still further examples, the barrier layer TOF-SIMS composition may include trace amounts of silicon. Notably, a friability of the barrier layer imparts a sharp increase in the number of counts in the TOF-SIMS analysis.
[0040] Preferably, the compositions include an aluminum surface carried by a substrate. The substrate can be composed of, for example, aluminum, an aluminum alloy, or stainless steel. The aluminum alloy can be selected from the series consisting of a 1000 series alloy, a 2000 series alloy, a 3000 series alloy, a 4000 series alloy, a 5000 series alloy, a 6000 series alloy, a 7000 series alloy, and a 8000 series alloy. In one preferable example, the aluminum alloy is a 6000 series alloy; in another preferable example, the aluminum alloy is a 3000 series alloy; in still another example the aluminum alloy is a 1000 series alloy. The aluminum or aluminum alloy can be cast, extruded, hot rolled, cold rolled, annealed, or hardened. In one preferable instance, the aluminum or aluminum alloy is extruded. In another instance, the aluminum or aluminum alloy is rolled. In still another instance, the cast, extruded, or rolled aluminum or aluminum alloy is annealed. In yet another instance, the cast, extruded, or rolled aluminum or aluminum alloy is hardened. In other examples the substrate can be, for example, stainless steel, a ceramic, or a plastic.
[0041] An important feature is an extraordinary resistance to corrosion and or degradation provided by the herein described silicate glass coating. Generally, the resistance to corrosion or degradation is determined by the performance of test samples in the following test methods. Therein, samples are evaluated on a “pass/fail” scale; typically, passing a specific test was indicated by no change in visual appearance at the conclusion of the test whereas failure of a specific test was indicated by significant corrosion or degradation of the sample. Some tests provided less binary results; in these circumstances samples were additionally graded on a “−/0/+” scale: where “−” equates to failure, “0” equates with a minor change in appearance (e.g., light discoloration, spotting, or clouding over less than 10% of the coated surface area), and “+” equates with no change in visual appearance. Herein, samples that exhibit no visual change in appearance (score a “+”) are considered to have “excelled” at the test.
[0042] In a first instance, the herein described coating provides the coated materials with resistance to acidic environments. That is, the coated product passes and/or excels on a “pH 1 Test”. The “pH 1 Test” is a 10 minute immersion in an aqueous 0.1 M HCl solution at ambient temperature (20-25° C.).
[0043] In a second instance, the herein described coating provides the coated materials resistance to basic environments. That is, the coated product excels on a “pH 13.5 Test”. The “pH 13.5 Test” is conducted at 25-30° C. by (a) 10 min immersion in pH 1 solution; (b) rinse in water and dry, (c) age at elevated temperature at 40° C. for 1 h, then without cooling down (d) 10 min immersion in pH 13.5 solution, and (e) rinse in water and dry. This test is commonly known as standard TL 182 (Volkswagen AG).
[0044] In another instance, the coated product passes and or excels on a 2 minute “pH 14 Test”, more preferably a 10 minute “pH 14 Test”, or even more preferably a 30 minute “pH 14 Test”. The “pH 14 Test” is conducted by immersing the test sample in a 1 M aqueous NaOH solution at 70° C. (pH 14). The sample is held in the caustic solution for at least two minutes, thereafter removed and rinsed with water and dried. Typical failure under the pH 14 Test was a sheeting or delamination of a coating. Accordingly, samples were evaluated on a pass/fail basis wherein samples that exhibited a delamination or sheeting failed whereas samples that maintained their integrity passed. In limited samples, a slight opacity (clouding) was observed after completion of the test; in these samples were considered to have passed the test. Preferably, samples exhibited no change (e.g., no clouding, no corrosion, no change in color) in visual appearance as a result of the pH 14 Test; these samples are considered to have “excelled” under the test conditions.
[0045] In yet another instance, the herein described coating provides the coated materials with resistance to a Copper Accelerated Acetic Acid Salt Spray (CASS) Test (see FIG. 6 ). Preferably, the coated product passes a “24-hour CASS Test”, a “48-hour CASS Test”, a “72-hour CASS Test”, and/or a “120 hour CASS Test”. The “CASS Test” is a known industry standard, e.g., ASTM B368-09. Typical failure under the CASS Test is pinhole corrosion. Accordingly, samples were evaluated on a pass/fail basis, wherein samples that exhibited pinhole corrosion failed whereas samples that maintained their integrity passed. In limited samples, slight changes in visual appearance were observed; these samples were considered to have passed the test. Preferably, samples exhibited no change in visual appearance as a result of the CASS Test; these samples are considered to have “excelled” under the test conditions. Additionally, preferred samples exhibited no change in visual appearance as a result of an Extended CASS Test (48 hours).
[0046] In still yet another instance, the herein described coated product passes a “Fogging Test.” The “Fogging Test” included subjecting the sample to nitric acid vapors in 95-100 percent humidity at about 38° C. for 72 hours.
[0047] A further failure test is an “abrasion test”. Herein, the abrasion test included 20 cycles (40 lengths) of polishing with a Grade 1 steel wool (medium; with a fiber width of 0.06 mm) at a force of 200 g/cm 2 . Additional abrasion testing can be conducted, e.g., an “Amtec Kistler Car Was Test” and/or a “Taber Test”.
[0048] Further failure tests include a “Heat Resistance Test” (120 hours at 200° C.), a Neutral Salt Spray Test (e.g., ASTM B117; 1,000 hours), and a “Humidity Test” (300 hours). Preferably, the herein described coated product passed these test, individually and as a group.
[0049] Preferably, the herein described coated product passes a “pH 1 Test”; passes a “pH 13.5 Test”, passes a 2 minute “pH 14 Test” (preferably, a 10 minute “pH 14 Test”, more preferably, a 30 minute “pH 14 Test”); and passes a “24-hour CASS Test” (preferably, a “48-hour Cass Test”, a “72-hour CASS Test”, or a “240-hour CASS Test”).
[0050] In another embodiment, the coated product includes a substrate carrying an aluminum oxide layer that is directly attached to a silicate glass layer. Here, the coated product can be free of a barrier layer, e.g., the aluminum oxide layer can be directly attached to the substrate. One example of an aluminum oxide layer directly attached to the substrate is physical vapor deposited (PVD) aluminum oxide carried by a substrate, where a PVD aluminum oxide layer was formed directly on the receiving substrate. The composition of the aluminum oxide layer (e.g., the PVD aluminum oxide layer) can be free of sulfur. Preferably, the aluminum oxide layer composition can consist of aluminum and oxygen, and more preferably, in a ratio of about 2:3 (e.g., Al 2 O 3 ). In another example, the aluminum oxide layer composition can include aluminum, oxygen and hydrogen. Furthermore, the aluminum oxide layer (e.g., the PVD aluminum oxide layer) can include or consist of a bayerite/boehmite region adjacent to the silicate glass layer.
[0051] Additionally disclosed is a process for preparing the above described surface coatings or coated products. Generally, the process includes coating an aluminum oxide with an aqueous silicate solution and then polymerizing and curing a silicate glass formed from the silicate solution. An important feature of the process, alluded to above in the description of the surface coatings, is preventing silicate penetration into the aluminum oxide and preventing aluminum dissolution and appearance in the silicate glass. The control of the resulting compositions provided by the herein disclosed process yields a coating or coated product with unexpected and exceptional resistance to corrosion and damage.
[0052] At a minimum, the process can include forming an aluminum oxide layer coated with an aqueous silicate solution and then polymerizing and curing a silicate glass on the aluminum oxide layer. For a complete understanding, the process is herein described with additional, preferable, steps applicable for the formation of the above described coatings or coated products.
[0053] The herein disclosure includes a process for preparing surface coating that can include forming a coated-aluminum-oxide layer by applying an aqueous silicate solution to an aluminum oxide layer having a thickness of about 1 μm to about 25 μm, the aluminum oxide layer consisting of a sealed, anodized-aluminum layer or a hydrated PVD alumina layer, the aqueous silicate solution having a pH of about 11 to about 13, a composition that includes a ratio of SiO 2 to M 2 O of about 3.5 to about 2, where M is selected from Li, Na, K, and a mixture thereof, and a ratio of SiO 2 to B 2 O 3 of about 10:1 to about 200:1; and thereafter, polymerizing and curing a silicate glass on the sealed, anodized-aluminum layer by (A) heating the coated, anodized-aluminum layer to a temperature of about 200° C. to about 500° C. or (B) exposing the coated, anodized-aluminum layer to an infrared source. The process can further include providing an aluminum surface; anodizing the aluminum surface to provide an unsealed, anodized-aluminum layer; and then hot sealing the unsealed aluminum oxide layer to provide a sealed, anodized-aluminum layer. The hot sealing can include a hot sealing time of less than 6 min/micron and at least 5 min/micron, 4 min/micron, 3 min/micron, 2 min/micron, 1 min/micron, 30 sec/micron, or 10 sec/micron; wherein forming the sealed, anodized aluminum layer from the unsealed-anodized-aluminum layer consists of the hot sealing process.
[0054] Still further, the process can includes a time between the conclusion of the hot sealing process and forming the coated, anodized-aluminum layer of less than 60, 45, 40, 35, 30, 25, 20, 15, 10 or 5 minutes. Preferably, the time is less than 5 minutes or is no more than the amount of time necessary to remove the sample from a hot sealing bath or apparatus, cool to about room temperature, and then immerse in the aqueous silicate solution (in practice, often less than 1 minute). In another instance, the sealed, anodized-aluminum layer may be held in a wet atmosphere, in water, or coated with water; before forming the coated, anodized-aluminum layer by applying the aqueous silicate solution.
[0055] Further disclosed in a multistep process that includes a first step of providing an aluminum oxide layer. The aluminum oxide layer can be prepared by anodizing aluminum or an aluminum alloy or by deposition of an aluminum oxide layer by, for example, physical vapor deposition (PVD). While chemically similar, the structures of the aluminum oxide layers provided by different methods are distinct. Anodization provides a well-known porous layer whereas PVD, typically, provides a dense non-porous layer. Prior to coating with the silicate solution, the aluminum oxide layer is, preferably, non-porous and/or includes a high proportion of hydroxyl groups on an outer surface.
[0056] The aluminum oxide layer can be provided (e.g., by anodization or PVD) on an aluminum, aluminum alloy, or other surface. In examples where the aluminum oxide layer is provided on an aluminum or aluminum alloy surface, the surface, preferably, has a <110> or a <112> orientation. In one particularly preferably instance, the aluminum or aluminum alloy surface has a <110> orientation. Notably, the aluminum or aluminum alloy surface is not single-crystalline and the surface orientation may include other crystal orientations. Herein, an aluminum or aluminum alloy that is designated as having a <110> orientation may include <100>, <111>, <211>, and <311> orientations. Preferably, the aluminum or aluminum alloy with the <110> orientation includes at least 50% <110>; more preferably 75% <110>; even more preferably, the non-<110> orientations, individually, occur as less than 20% of the surface orientation. In another example, the surface can have a <200> orientation. Preferably, the aluminum or aluminum alloy with the <200> orientation includes at least 75%, 80%, 85%, 90%, 95%, or about 100% <200> surface orientation.
[0057] The aluminum or aluminum alloy can have a coarse grain or a fine grain size (as determined by surface analysis). Preferably, the aluminum or aluminum alloy has a fine grain size. For example, the aluminum or aluminum alloy can have an average grain size of less than 500 μm, 400 μm, 300 μm, 250 μm, 200 μm, 150 μm, or 100 μm. In one example, the aluminum or aluminum alloy has an average grain size of about 250 μm, 200 μm, 150 μm, 100 μm, 75 μm, 50 μm, or 25 μm.
[0058] In one preferable example, the aluminum oxide layer is exposed to water at a temperature of at least 85° C. That is, the process can include forming a sealed, anodized-aluminum layer by a hot sealing process. The hot sealing process includes exposing the anodized aluminum, preferably, a hard-anodized-aluminum layer, to water at a temperature of at least 85° C., 90° C., 95° C., 98° C., 99° C., 100° C., or 101° C. In one instance, hard-anodized aluminum can be hot sealed in boiling or near boiling water; in another instance the hard-anodized aluminum can be steam sealed. Preferably, anodized aluminum is hot sealed in boiling or near boiling water. The water is preferably free of silicates and transition metals (e.g., nickel), and/or other sealing additives. The hot sealing of the hard-anodized-aluminum layer can include exposing the hard-anodized aluminum to hot water for at least 5 min/micron, 4 min/micron, 3 min/micron, 2 min/micron, 1 min/micron, 30 sec/micron, or 10 sec/micron. The process can, alternatively, include exposing a PVD alumina layer to water at a temperature of at least 85° C., 90° C., 95° C., 98° C., 99° C., 100° C., or 101° C. to form a hydrated PVD alumina. In one instance, the PVD alumina layer can be exposed to boiling or near boiling water; in another instance the PVD alumina layer can be exposed to steam. Preferably, the PVD alumina layer is exposed to boiling or near boiling water, where the water is free of silicates, transition metals, and/or sealing additives. Alternatively, a high hydroxyl content aluminum oxide layer can be provided by PVD (e.g., PVD of a boehmite/bayerite layer). Preferably, the process includes forming aluminum hydroxides on exposed surface of the aluminum oxide layer during the exposure of the materials to water at a temperature of at least 85° C. Optionally, the process can include forming aluminum hydroxides within the aluminum oxide layer. More preferably, the process includes forming a boehmite/bayerite region in the aluminum oxide layer.
[0059] The aluminum oxide layer (e.g., the sealed, anodized aluminum layer or the hydrated PVD alumina layer) can have a thickness of about 1 μm to about 50 μm. Specifically, the aluminum oxide layer can have a thickness of less than about 50 microns, 40 microns, 30 microns, 25 microns, 20 microns, 10 microns, 5 microns, 4 microns, 3 microns, 2 microns, 1 micron, or 500 nm. Preferably, the aluminum oxide thickness is within a range of about 1 to about 30 microns, about 2 to about 25 microns, about 3 to about 20 microns, or about 5 to about 25 microns. In one particular example, the aluminum oxide layer has a thickness less than about 10 microns.
[0060] In a specific example, the aluminum oxide layer is a sealed, anodized-aluminum layer which has a composition that is free of silicates, preferably, free of silicon and, more preferably, free of nickel. For example, the sealed, anodized-aluminum layer can have a composition that includes or consists of about 75 wt. % to about 85 wt. % Al 2 O 3 , about 3.5 wt. % to about 5.5 wt. % H 2 O, and about 12.5 wt. % to about 17.5 wt. % SO 3 . In another specific example, the aluminum oxide layer is a hydrated PVD alumina layer which has a composition that includes or, preferably, consists of aluminum, oxygen and hydrogen.
[0061] The process can then include coating the aluminum oxide layer with an aqueous silicate solution; that is, forming a coated, aluminum oxide layer, where the aluminum oxide layer carries a layer/coating of an aqueous silicate solution. For example, the coated, aluminum oxide layer can be a coated, anodized-aluminum layer or a coated PVD alumina layer. In one particularly preferable example, the process includes applying an aqueous silicate solution to the sealed, anodized-aluminum layer. Alternatively, the process can include applying the aqueous silicate solution to a hydrated PVD layer. Preferably, the aqueous silicate solution is maintained at a temperature below 30° C., 25° C., or 20° C.
[0062] The coated aluminum oxide layer preferably includes or consists of the aluminum oxide layer (e.g., the sealed, anodized-aluminum layer) and a silicate solution layer. The silicate solution layer can have a thickness of about 0.1 μm to about 5 μm, about 0.5 μm to about 4 μm, or about 1 μm to about 3 μm.
[0063] The aqueous silicate solution has a pH of about 11 to about 13, about 11 to about 12, or about 11 to about 11.5. Preferably, the aqueous silicate solution has a composition that includes a ratio of SiO 2 to M 2 O of about 3.5 to about 2, about 3.5 to about 2.25, about 3.5 to about 2.5, about 3.5 to about 2.75, or about 3.5 to about 3, where M is selected from Li, Na, K, and a mixture thereof. More preferably, the aqueous silicate solution has a composition that includes a ratio of SiO 2 to B 2 O 3 of about 10:1 to about 200:1.
[0064] In one instance, the coating process can include immersing the aluminum oxide layer in the aqueous silicate solution and then withdrawing the coated, anodized-aluminum layer from the aqueous silicate solution. In another instance, the coating process can include spray coating or roll coating the aluminum oxide layer with the aqueous silicate solution.
[0065] The coating process, preferably, excludes the formation of aluminosilicates. More preferably, the process includes preventing the formation of an aluminosilicate. In one example, preventing the formation of aluminosilicate can include preventing the penetration of the aqueous silicate solution into aluminum oxide layer. More preferably, preventing the formation of the aluminosilicate includes preventing the dissolution of aluminum from the aluminum oxide layer into the aqueous silicate solution. For example, the coating process prevents the diffusion of the silicate into the alumina and/or the interdiffusion of the silicate and alumina thereby providing a product that is free of an aluminosilicate or silicate/alumina interdiffusion. Processes for preventing the penetration of the aqueous silicate solution into the aluminum oxide layer can include sealing pores in the aluminum oxide layer to reduce silicate solution penetration and thereby formation of interstitial Al/Si layers, providing a non-porous aluminum oxide layer, and/or rapidly drying the aqueous silicate solution to reduce or eliminate the mobility of the silicon atoms. Processes for preventing the dissolution of aluminum from the aluminum oxide layer into the aqueous silicate solution can include incompletely hydrating the aluminum oxide layer or reducing the percentage of Al(OH) 3 in the aluminum oxide layer, conducting the coating process at a reduced temperature (e.g., by chilling the aqueous silicate solution and/or the aluminum oxide layer), and/or rapidly drying the aqueous silicate solution. In one example, the process can include preheating the coated, anodized-aluminum layer to a temperature of about 30° C. to about 100° C. immediately after the formation of the coated aluminum oxide layer. In another example, the process can include drying the coated, anodized-aluminum layer immediately after the formation of the coated aluminum oxide layer. In another example, the process can include reducing a water content in the coated, anodized-aluminum layer by at least 25%, 50%, or 75% immediately after the formation of the coated aluminum oxide layer.
[0066] The process, preferably, further includes quickly applying the aqueous silicate solution to the aluminum oxide layer after hot sealing (i.e. exposing the aluminum oxide layer to the hot water). For example, the process can include forming a coated, anodized-aluminum layer by applying the aqueous silicate solution within 45, 40, 35, 30, 25, 20, 15, 10 or 5 minutes of a conclusion of the hot sealing process. That is, the process can include immersing the sealed, anodized-aluminum layer in the aqueous silicate solution; or spray coating or roll coating the sealed, anodized-aluminum layer with the aqueous silicate solution within 45, 40, 35, 30, 25, 20, 15, 10 or 5 minutes of a conclusion of the hot sealing process. In another example, the process can include forming a coating PVD alumina layer by applying the aqueous silicate solution within 45, 40, 35, 30, 25, 20, 15, 10 or 5 minutes of removal from exposure to water at a temperature of at least 85° C.
[0067] Alternatively, the process can include holding or maintaining the hot sealed aluminum oxide layer in an atmosphere with a relative humidity of at least 50%, 60%, 70%, 80%, 90%, or about 100% prior to coating the aluminum oxide layer with the aqueous silicate solution. For example, a sealed, hard-anodized aluminum layer can be maintained in an atmosphere with a relative humidity of at least 50%, 60%, 70%, 80%, 90%, or about 100% for a period longer than 45 min, 1 h, 2 h, 3 h, or 4 h, and then coating with an aqueous silicate solution. In another example, the process can include holding or maintaining the hot water exposed aluminum oxide layer in water and then coating with an aqueous silicate solution. Preferably, the aluminum oxide layer is held in water at a temperature of less than 75° C., 65° C., 60° C., 55° C., 50° C., 45° C., 40° C., 35° C., 30° C., 25° C., or 20° C. For example, the process can include holding, maintaining, or submerging the sealed, anodized-aluminum layer in water; and then forming the coated, anodized-aluminum layer by applying the aqueous silicate solution.
[0068] The coated, aluminum oxide layer includes an aqueous solution of an alkali metal silicate carried on the surface of an aluminum oxide. Without being bound to theory, the dried, coated, aluminum oxide layer can include sufficient water to allow for the dissolution of the alkali metal silicate from the aluminum oxide layer. That is, prior to a polymerization and curing step, the alkali metal silicate carried on the surface of the aluminum oxide layer can be dissolved or removed from the surface by, for example, washing the surface in water or an alkali solution (e.g., 0.01 M aq NaOH, or 0.1 M aq NaOH).
[0069] An important step in the preparation of the coated/corrosion resistant product is the polymerization and curing of a silicate glass. The silicate glass can be formed from the heating and dehydration of an aqueous solution of an alkali metal silicate carried on the surface of the aluminum oxide layer. Alternative, the silicate glass can be formed by the infrared activation of the aqueous solution of alkali metal silicate carried on the surface of the aluminum oxide layer.
[0070] In one example, the heating of the coated, aluminum oxide layer facilitates the removal of water from the coating, dehydration-polymerization of SiO 4 groups, and the curing of the silicate glass. For example, the process can include polymerizing and curing a silicate glass by heating the coated, anodized-aluminum layer to a temperature of about 200° C. to about 500° C. The polymerization and curing temperature can be in the range of about 200° C. to about 500° C., preferably this temperature is about 200° C. to about 400° C., about 250° C. to about 350° C., about 260° C. to about 325° C., or about 260° C. to about 300° C. More preferably, the polymerizing and curing of the silicate glass includes heating the surface of the substrate, i.e., the coated, anodized-aluminum layer, to a temperature of about 240° C. to about 320° C., about 260° C. to about 300° C., about 270° C. to about 290° C., or about 280° C.
[0071] The polymerization and curing of the silicate glass preferably includes the rapid heating and dehydration of the aqueous alkali metal silicate. Unexpectedly, the coated, aluminum oxide layer is resistant to the well-known cracking and/or crazing of the surface caused by the rapid heating and/or dehydration of the aluminum oxide layer (see FIG. 7 ). Whereas aluminum oxide layers would crack, craze, or delaminate; the coated, aluminum oxide layer can be heated to the polymerization and curing temperature a rate of 1° C./s, 10° C./s, 25° C./s, 50° C./s, or 100° C./s; or a rate of at least 10° C./s, 25° C./s, 50° C./s, or 100° C./s. Whereas visual identification of cracking, crazing, or delamination is readily apparent, damages surfaces are mopre readily identifies by failure of the herein described test methods (e.g., the “pH 1 Test”, the “pH 14 Test”, or the “CASS Test”). In one preferable example, the polymerization and curing of the silicate glass includes the heating of the silicate layer (solution/glass) but incomplete heating of the underlying substrate.
[0072] The heating and dehydration of the aqueous silicate solution carried on the surface of the aluminum oxide layer can be accomplished by, for example, direct heating in an oven, heating by lamps, a vacuum process, or a combination thereof. In one preferable example, the coated, aluminum oxide layer is heated in an oven. In one instance, the coated, aluminum oxide layer is heated in a conventional oven. In another instance, the coated, aluminum oxide layer is heated in a convection oven that allows for the more rapid and even elevation of the temperature of the coated, aluminum oxide layer. In yet another instance, the coated, aluminum oxide layer is carried through a heating zone (e.g., in a conveyor oven). Even more preferably, the coated, aluminum oxide is heated to the polymerization and curing temperature at a rate of at least 20° C./s, is heated for a heating time of less than about 30 min, and is then removed from the heat source to a temperature of less than 50° C., 40° C., or 30° C., preferably removed from the heat source to a temperature of about 20-25° C. (standard room temperatures). Preferably, the direct heating is for a heating time of less than about 5 min, 10 min, 15 min, 20 min, 25 min, or 30 min. More preferably, the heating time is less than about 15 min.
[0073] In another example, the silicate glass can be formed by the infrared activation of the alkali metal silicate layer carried on the surface of the aluminum oxide layer. For example, the coated, aluminum oxide layer can be polymerized and the silicate glass cured by exposing the coated, anodized-aluminum layer to an infrared (IR) source. In one instance, the coated, aluminum oxide layer is exposed to IR heat lamps (e.g., short wave or mid wave lamps). In another instance the coated, aluminum oxide layer is carried through an IR exposure region (e.g., on a conveyor). The IR transmission from the IR source can be from about 1 to about 3 μm (short wave IR), from about 3 to about 5 μm (mid wave IR, or intermediate IR), or from about 2 to about 4 μm (IR-B). Preferably, the IR exposure is for an exposure time of less than about 15 seconds, 30 seconds, 45 seconds, 60 second, 90 seconds, 120 seconds, 3 min, 4 min, 5 min, or 10 min. More preferably, exposure time of less than about 15 seconds, 30 seconds, 45 seconds, 60 second, 90 seconds, or 120 seconds.
[0074] Unexpectedly, the IR cured, silicate glass is resistant to the well-known cracking and/or crazing of the surface. Whereas aluminum oxide layers crack, craze, or delaminate; the coated, aluminum oxide layer can be exposed to the IR source and the resultant cured silicate glass appears as a uniform unbroken surface (see FIG. 7 ). Whereas visual identification of cracking, crazing, or delamination is often visually apparent, damaged surfaces are more readily identified by failure of the herein described test methods (e.g., the “pH 1 Test”, the “pH 14 Test”, and/or the “CASS Test”). Herein, the products carrying the IR cured silicate glass pass the “pH 1 Test”, the “pH 14 Test”, and the “CASS Test”.
[0075] In one specific example, the process of preparing a surface coating can consist of forming a coated, anodized-aluminum layer by dip coating, spray coating, or roll coating a sealed, anodized-aluminum layer having a thickness of about 1 μm to about 25 μm with an aqueous silicate solution. The coated, anodized-aluminum layer can consist of the sealed, anodized-aluminum layer and a silicate solution layer, where the silicate solution layer has a thickness of about 1 μm to about 3 μm, and the sealed, anodized-aluminum layer has a composition that includes about 75 wt. % to about 85 wt. % Al 2 O 3 , about 3.5 wt. % to about 5.5 wt. % H 2 O, and about 12.5 wt. % to about 17.5 wt. % SO 3 , and is free of nickel and silicon. The process thereafter includes polymerizing and curing the coated, anodized-aluminum layer to form a non-porous silicate glass, the polymerizing and curing includes heating the coated, anodized-aluminum layer to a temperature of about 225° C. to about 300° C. Wherein, the above described thickness, composition, and heating features can be further refined by the corresponding general disclosures.
[0076] In another specific example, the process can consist of hot sealing an anodized aluminum layer by exposing the anodized aluminum layer to water at a temperature of at least 85° C., 95° C., or 100° C. The process thereafter includes either (A) forming a coated, anodized-aluminum layer by dip coating, spray coating, or roll coating the sealed, anodized-aluminum layer with an aqueous silicate solution within 20, 15, 10 or 5 minutes of a conclusion of the hot sealing process, or (B) maintaining the sealed, anodized-aluminum layer in water after the hot sealing process and then forming the coated, anodized-aluminum layer by dip coating, spray coating, or roll coating with the aqueous silicate solution. Herein, the sealed, anodized-aluminum layer has a thickness of about 1 μm to about 25 μm, the coated, anodized-aluminum layer consists of the sealed, anodized-aluminum layer and a silicate solution layer that has a thickness of about 1 μm to about 3 μm, and the sealed, anodized-aluminum layer has a composition that includes about 75 wt. % to about 85 wt. % Al 2 O 3 , about 3.5 wt. % to about 5.5 wt. % H 2 O, and about 12.5 wt. % to about 17.5 wt. % SO 3 , and is free of nickel and silicon. Thereafter, the process includes polymerizing and curing the coated, anodized-aluminum layer to form a non-porous silicate glass, the polymerizing and curing includes heating the coated, anodized-aluminum layer to a temperature of about 225° C. to about 300° C. Wherein, the above described thickness, composition, and heating features can be further refined by the corresponding general disclosures.
[0077] In yet another specific example, the process of preparing a surface coating can consist of forming a coated, PVD alumina layer by dip coating, spray coating, or roll coating a PVD alumina layer having a thickness of about 1 μm to about 25 μm with an aqueous silicate solution. The coated, PVD alumina layer can consist of the PVD alumina layer and a silicate solution layer, where the silicate solution layer has a thickness of about 1 μm to about 3 μm. The process thereafter includes polymerizing and curing the coated, PVD alumina layer to form a non-porous silicate glass, the polymerizing and curing includes heating the coated, PVD alumina layer to a temperature of about 225° C. to about 300° C. Wherein, the above described thickness, composition, and heating features can be further refined by the corresponding general disclosures.
Examples
[0078] By way of example and not limitation, test samples, prepared as follows, are illustrative of various embodiments of the present disclosure and further illustrate experimental testing conducted.
[0079] The herein described aqueous silicate solution can be an alkali-borosilicate solution containing a mixture of sodium and lithium metal counterions. The alkali-borosilicte solution can be prepared by combining concentrated, commercial, liquid sodium silicate and lithium silicate solutions. Then adding to this lithium-sodium solution a borax solution (sodium tetraborate decahydrate (Na 2 B 4 O 7 .10H 2 O) in water). The final borax concentration in the coating solution can be between 1-5% by weight. In one example, the aqueous silicate solution contains 13.0% SiO 2 , 1.7% Na 2 O, 1.2% Li 2 O, 1.1% B 2 O 3 , and 83.0% H 2 O by weight, had a specific gravity of about 1.15. Prior to use, the solution was filtered through a 1.2 mm filter. The aqueous silicate solution has a specific gravity of 1.136 and was held at 20° C.
[0080] The following general procedures were used to produce test samples:
[0081] Anodization: Component testing was conducted on automotive-trim test forms which were produced by extruding and heat treating a 6061 series aluminum alloy. The test forms were approximately 100 mm by 500 mm and included a multitier cross-sectional profile. The aluminum form was degreases (alkaline), desmutted (nitric acid), and then anodized in a sulfuric acid bath at 19° C., for 15 min, at 16V and 1.5 A/dm 2 . The anodized sample was then rinsed three times with DI water. This yielded an unsealed, anodized-aluminum layer carried on the aluminum form.
[0082] Hot Sealing: following anodization and unless otherwise noted, test samples were hot sealed at about 97° C. following standard industrial procedures. A test standard was established with a hot sealing time of 2 minutes per micron of anodization (e.g., 20 minutes for a 10 micron thick anodized layer).
[0083] Coating: test samples (hot sealed or not) were coated with aqueous silicate solution by immersion, spray coating, or roll coating to provide a coating thickness of about 1 μm to about 5 μm. Preferably, test samples were immersed in the aqueous silicate solution for five minutes. Unless otherwise noted the aqueous silicate solution was the above described alkali-borosilicate solution.
[0084] Polymerizing and Curing: coated test samples were subjected to elevated temperatures to polymerize and cure the silicate coatings. The temperatures can be applied by standard, convection, or IR oven. The curing times (time subjected to elevated temperatures) ranged from about 3 to 30 minutes. No benefit was incurred by heating beyond 30 minutes.
[0085] Test samples were subjected to the following testing: a 24 hour CASS test, a 2 minutes pH 14 test, a fogging test, and an abrasion test. Table 1 provides data on the preparation of prior art comparative samples:
[0000]
Anodize
Sample
to
Curing
Number
Seal
Coat Time
Coating Type
Time 1
Ref.
C1
None
0
ABS 2
3 min
Jennings 3
C2
None
0
ABS 2
7 min
Jennings 3
C3
None
0
ABS 2
15 min
Jennings 3
C4
None
0
ABS 2
30 min
Jennings 3
C5
800 sec Cold
0
0.5 wt. %
0
Lawlor 4
then 800 sec
sodium
Hot
silicate
1 Time at a curing temperature of 280° C.
2 The above described alkali-borosilicate solution.
3 U.S. Pat. No. 8,173,221
4 U.S. Pat. No. 7,851,025
[0086] Table 2 provides data on the preparation of comparative samples that can be viewed as amendments on the prior art:
[0000]
Anodize
Sample
to
Curing
Number
Seal
Coat Time
Coating Type
Time 1
Ref.
C6
None
5 h
ABS 2
15 min
Jennings 3
C7
None
24 h
ABS 2
15 min
Jennings 3
C8
800 sec Cold
0
ABS 2
15 min
Lawlor 4
then 800 sec
Hot
1 Time at a curing temperature of 280° C.
2 The above described alkali-borosilicate solution.
3 U.S. Pat. No. 8,173,221
4 U.S. Pat. No. 7,851,025
[0087] Table 3 provides data on the preparation of herein disclosed samples using the above described alkali-borosilicate solution:
[0000]
Sample
Hot Seal 1
Seal to Coat Time 2
Curing Time 3
1
0.5
0
15
2
2
0
15
3
6
0
15
4
2
5 4
15
5
2
24 4
15
6
2
5 5
15
7
2
24 5
15
8
2
0
3
9
2
0
7
10
2
0
30
1 Hot seal time in minutes per micron of anodized layer thickness.
2 The time in hours between hot sealing and coating with the alkali-borosilicate solution.
3 Time at a curing temperature of 280° C.
4 Samples were maintained in air at room temperature for the time between hot sealing and coating.
5 Samples were maintained in water at room temperature for the time between hot sealing and coating.
[0088] Table 4 provides test results for all samples.
[0000]
Sample
24 hour
2 min
Number
CASS
pH 14
Fogging
Abrasion
C1
F
P(0)
F
P(0)
C2
F
P(+)
F
P(0)
C3
F
P(+)
P(0)
P(0)
C4
F
P(+)
P(+)
P(0)
C5
F
F
F
F
C6
F
P(0)
P(0)
P(0)
C7
F
P(0)
P(0)
P(0)
C8
F
P(+)
F
P(0)
1
P(+)
P(+)
P(+)
P(+)
2
P(+)
P(+)
P(+)
P(+)
3
P(0)
P(0)
P(+)
P(+)
4
P(0)
F
P(0)
P(0)
5
P(0)
F
P(0)
P(0)
6
P(0)
P(0)
P(0)
F
7
P(0)
P(0)
P(0)
F
8
P(+)
P(0)
F
P(0)
9
P(0)
P(+)
P(0)
P(0)
10
P(+)
P(+)
P(+)
P(+)
[0089] TOF-SIMS testing: Comparative Sample 3 (unsealed) and Sample 2 (sealed) were ion milled and compositional analysis was completed by time-of-flight secondary ion mass spectroscopy (TOF-SIMS). Milling distances were approximately 1 micron per cycle. Table 5 provides atomic percentages of Silicon and Aluminum (balance Oxygen):
[0000]
Comparative
Sample C3
Sample 2
Milling Cycle
Si
Al
Si
Al
1
29.4
0.9
30.0
1.4
2
28.6
0.1
29.3
0.1
3
28.5
0.1
29.3
0.2
4
28.3
0.0
3.2
29.3
5
28.7
0.2
0.0
34.0
6
1.4
31.7
0.0
33.8
7
1.3
32.9
0.0
34.2
8
0.6
32.7
0.0
34.3
9
0.4
33.2
0.0
34.9
10
0.4
33.1
0.0
34.4
11
0.8
33.3
0.0
34.8
12
1.0
32.7
0.0
34.9
13
0.6
33.0
0.0
34.7
14
0.4
33.7
0.0
90
15
0.5
33.2
0.0
100
16
0.5
37.9
0.0
100
17
0.0
99.5
0.0
99.7
18
0.0
99.8
0.0
100
[0090] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims. | Metal products having improved properties and processes for preparing the metal products are provided. The present disclosure provides for a metal product comprising a metal surface, an oxide layer and a glass layer. The glass layer is provided by coating a stable aqueous silicate or borosilicate solution onto the metal surface and curing the aqueous solution to produce a glass layer. The metal products have surface characteristics that outperform all anodized metal surfaces. | 2 |
This application is a continuation-in-part of copending U.S. application Ser. No. 09/672,923, filed Sep. 28, 2000.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is directed to a wind powered generating device comprising a tube cluster, a collector assembly, and a turbine assembly which improves the efficiency of such devices.
2. Description of the Related Art
Wind-powered generators have been around for some time. In conventional wind-powered generators, a sustained ambient wind speed of 11-13 mph is required to attain “cut-in” speed (the point at which the turbine is generating sufficient power to be safely and efficiently placed on the grid). At cut-in speed, conventional turbines are generating only about 20% of their rated power, and they do not reach their peak rated power output until wind speeds reach 25-30 mph. This means that there are relatively few places in the world in which wind generators can be considered a reliable source of electricity.
Over the years, sophisticated control systems and blade designs have been developed to assure relatively stable output characteristics over a wide range of wind conditions, but despite a steady flow of incremental improvements, the need for an ambient wind speed of at least 11-13 mph persists. Before a site is considered to be commercially viable, it must reliably be subject to wind speeds much higher than those necessary for cut-in speed, consistently bringing the turbine up to or at least close to its full rated power. In the United States, there are limited areas where such conditions exist.
The problem of finding suitably windy sites is not presently the only issue that is hindering the growth of the wind power industry. With the height of the latest wind generators approaching 230 ft., wind farms utilizing present designs are increasingly becoming a hazard to migratory birds and private air traffic. Construction and maintenance costs are skyrocketing as these new machines tower to ever increasing heights, and discussions about noise and visual effects on the landscape are also becoming contentious.
A widely accepted, practical formula for estimating the power output of a wind turbine is as follows:
P= 0.5× rho×A×CP×V 3
where
P=power in watts (746 watts=1 hp)(1,000 watts=1 kilowatt)
rho=air density (about 1.225 kg/m 3 at sea level, less at higher altitudes)
A=the swept area of the rotor exposed to the wind (m 2 )
CP=Coefficient of performance (0.59 {the Betz Limit} is the maximum theoretically possible; 0.35 is considered to be a good design)
V=wind speed in meters/sec (20 mph=9 m/s)
Other related variables include:
Ng=generator efficiency (50% for a car alternator, 80% or possibly more for a permanent magnet generator or grid-connected induction generator)
Nb=gearbox/bearing efficiency (good designs can yield an efficiency as high as 95%)
From the above formula, it can be seen that the easiest way to increase the power output of a wind turbine is to increase the velocity of the air passing the capture area (the area swept by the turbine blades). Because power increases by the cube of V, even small increases in wind velocity within the capture area yield relatively large increases in power output. Unfortunately, manipulating the wind speed using conventional free-air designs is not possible, since, by definition, the wind speed is the ambient wind speed. If, however, the air speed passing the turbine blades could be accelerated, the following benefits would result:
1. Wind generators would reach both cut-in speed and full rated power at lower ambient wind speeds. This could result in raising large parts of the world by as much as a whole power class (as defined by the United States Department of Energy), meaning that many areas which are now considered unsuitable as wind sites would become available as viable sites. The resultant decentralization of generators would insure that the grid as a whole was less vulnerable to the uncertainties of local weather conditions.
2. Intermittency (the time that the turbine spends below its cut-in speed) would be reduced, and conversely, availability would increase, resulting in an increase in annual energy output. This increase in efficiency would lower the average cost of power generation, making wind even more competitive with other sources of electricity.
Furthermore, conventional free-air turbines are engineered to have a service life of between 20 and 24 years, with scheduled periodic maintenance and one major overhaul at some point in time near mid-life. One of the most persistent problems that has plagued the industry has been a rate of component failure, especially blade failure, which is higher, sometimes much higher, than that predicted by computer models. This disparity between predicted and actual component life has been suggested by engineers to be due in great measure to the sheer number of unpredictable variables in a free-air system. The speed of the wind typically increases as one rises above the frictional elements close to the ground. This means that the forces that are exerted on the blade components traveling through the top of the rotor arc are significantly greater than those at the bottom of the arc. In addition to the cyclic flexing of the blades as they are subjected to these differences in wind speeds, they are also subject to alternating states of compression and tension as they travel around the hub. Wind gusts, off-axis buffeting, and structural harmonics provide additional sources of chaotic loading to the system, stressing not just the blade set, but the rotor hub, gearbox, and all associated bearings.
The cost of refitting a 1 megawatt free-air turbine with a new blade set, which typically has a diameter of approximately 60 meters, can easily exceed $300,000 U.S. (1999), which is about one third of the installed cost of the unit. From this we can see that any improvements which are capable of extending the service life of the system have the potential to make wind energy a more competitive alternative to other forms of power generation.
Present tower designs also produce the undesirable effect of stroboscopic flicker, which occurs to a stationary viewer on the ground when each blade passes between the viewer and the sun. This effect can be annoying to residents living within view of the towers, especially at those times of day when the sun is low in the sky.
Early designs in power generating devices have taken various approaches to maximizing efficiency while considering related design parameters. U.S. Pat. No. 1,600,105 issued to Fonkiewicz in 1923 shows a power generating device with a vertical stack having a turbine within, and radially extending tunnels that communicate with the stack, the tunnels being located below the ground surface and having openings in the ground. U.S. Pat. No. 4,036,916 issued to Agsten in 1977 shows a wind driven electric power generator with an updraft natural draft cooling tower having a hyperbolic veil with a wind driven electric generator system positioned at a narrowed area of the hyperbolic veil. U.S. Pat. No. 581,311 issued to Scovel in 1897 shows a rotatable hood positioned on top of a tube containing fans, which rotates to capture wind and direct wind to the fans. U.S. Pat. No. 4,049,362 issued to Rineer in 1977 shows airfoil panels utilizing fabric to capture wind to generate power. Finally, U.S. Pat. No. 4,779,006 issued to Wortham in 1988 shows a hybrid solar-wind energy conversion system having a “J” shaped tubular stack with a generator fan positioned in a tube below the surface of the ground.
In general, however, none of these related art references utilize strong lightweight structures that are self-regulating and easily turn to face the incoming wind, redirecting a substantial portion of the kinetic energy present in the ambient air stream into a tube set, where the air is channeled into a below-ground turbine located at a narrowing in an output tube which takes advantage of the Venturi effect, enabling significant efficiency and operating capability even at low wind speeds.
SUMMARY OF THE INVENTION
An object of the invention is to create a device that will collect, redirect, and accelerate ambient air, then channel it to the capture area of a turbine, thereby surpassing the performance of a conventional wind turbine operating in free air, and other conventional designs, with minimal noise and environmental impact, allowing economical operation in areas that were infeasible with previous designs.
This object is achieved with a wind-powered generation device comprising a tube cluster, collector assemblies, and a turbine assembly where the tube cluster and turbine assembly are primarily underground, and the central outlet tube is narrowed/pinched at the center to increase the rate of airflow past the turbine by taking advantage of the known Venturi effect. Lightweight, self-regulating collector assemblies gather a much greater volume of air than could be captured by a turbine rotor assembly in free air while greatly reducing the variability in the speed of the wind passing the blades. The tube set which channels the collected air and accelerates it as it passes the rotor, combined with the rotor which operates on a plane parallel to the ground, creates a system which significantly reduces the amount of buffeting, tension-compression variability, asymmetrical loading, and other elements of component stress, both cyclic and non-periodic, that are major sources of fatigue-related structural failure. The resultant increase in reliability and service life, and the reduction in maintenance costs, effectively lower the per-kilowatt cost of generating energy. Additionally, the present design eliminates the flicker effect produced by existing tower designs because its turbine blade is underground.
In areas where wind energy may be marginal or intermittent but heat energy is abundant and readily available, an additional mechanism may be used to boost the efficiency of the system. The rising of warm air is a well-known phenomenon and hence heat injected into the air stream at the proper place in the main outlet tube would serve to boost the performance of the system. Two potential sources of heat are solar and geothermal.
Well-planned combinations of functions provide investors with an extra measure for profit, thus encouraging more investment in environmentally sound generating sources such as wind. For example, during periods of high wind and low demand, generators placed next to coastlines could be taken off of the power grid and put to other tasks, such as the purification and desalination of seawater, the creation of oxygen gas or hydrogen fuel for fuel cells and other hydrogen-powered equipment, and other valuable commodities that can be produced by way of electrolytic reactions.
The system may be tuned by varying parameters on the open tubes to promote phase cancellation of low-frequency acoustic energy (ranging from below 8 Hz to above 20 Hz). This may be needed for the following reason: because of the low rotational speeds of the turbine blades, the peak acoustic energy radiated by the current generation of turbines is in the infrasonic range (8-12 Hz) for large diameter turbines, and in the low-frequency end of the audible spectrum (20 Hz) for smaller turbines or those with multiple blades. Although powerful infrasonic waves were found by the U.S. military to have deleterious effects such as nausea, vomiting, and dizziness on humans, acoustic pulses at these frequencies are generally considered to be more of an annoyance than anything else and the problems they create are generally overcome by the use of ear plugs. Other mechanisms for dealing with this issue may be considered as well.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, together with further advantages, is explained in greater detail below with reference to the drawings.
FIG. 1 is a perspective view of the overall wind powered generator device;
FIG. 2 is a perspective view of the tube cluster;
FIG. 3 is a perspective view of the collector assembly with a sail cover deployed;
FIG. 4 is a perspective view of the central outlet tube showing the turbine and generator nacelle;
FIG. 5 is a perspective view of a flattened central outlet tube and turbine;
FIG. 6 is a perspective view of the collector assembly;
FIG. 7 is a perspective view of an inlet tube having an oval cross-section, with a support and an adjoining duct;
FIG. 8 is a perspective view of the inlet tube of FIG. 7 without the adjoining duct;
FIG. 9 is a perspective view of an inlet tube having a rectangular cross-section, with an adjoining duct;
FIG. 10 is a perspective view of the inlet tube of FIG. 9 without the adjoining duct and having a support;
FIG. 11 is a perspective view of the collector assembly with the two-piece sail deployed;
FIG. 12 is a perspective view of the drum tensioner;
FIG. 13 is a perspective view of the collector assembly with the rod tensioner;
FIG. 14 is a perspective view of the rod tensioner;
FIG. 15 is a perspective view of the collector assembly with the spring tensioner;
FIG. 16 is a perspective view of the spring tensioner;
FIG. 17 is a perspective view of the collector assembly with the elastic tensioner;
FIG. 18 is a perspective view of the elastic tensioner;
FIG. 19 is a perspective view of an alternative embodiment comprising a steering sail; and
FIG. 20 is a perspective view of an alternative embodiment of the wind powered generator device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows the overall wind powered generator device 1 that comprises a tube cluster 20 , collector assemblies 60 , and a turbine assembly 45 .
According to FIG. 2, the tube cluster 20 comprises a number of inlet tubes 21 , and a central outlet tube 40 . In operation, tube clusters may be substantially buried underground, eliminating the hazard to migrating birds and private air traffic that current free-air turbine designs present. The sum of the cross-sectional areas of the inlet tubes should be greater than the cross-sectional area of the outlet tube for the system to operate efficiently. The central outlet tube 40 is pinched to provide a narrow center 23 with a smaller radius than the remainder of the tube in order to invoke the known Venturi effect which states that at any given pressure and rate of air inflow through the system, air must accelerate as it passes through a narrower portion of a tube. With the addition of a few simple collector assemblies 60 (FIG. 6) mounted on top of the inlet tubes 21 , ambient air is redirected, thereby pressurizing this system of tubes. This management and redirection of airflow is an important element for increasing the efficiency of the system. The inlet tube collector ends 22 are arranged in a staggered manner in order to minimize the occurrence of multiple tubes aligning with the wind, causing one collector assembly 60 to form a “wind shadow” in front of another, resulting in a pressure drop in the system and a resultant drop in output power.
In FIG. 4, the central outlet (main) tube 40 is shown with the turbine assembly 45 which comprises the turbine 41 having turbine blades 42 , and a generator nacelle 43 suspended vertically in the central outlet tube 40 . Air captured and redirected by the collectors 60 is accelerated as it passes the narrow section 46 of the central outlet tube 40 and the plane of the turbine blades 42 . The transition from a vertical to a horizontal axis turbine should be possible with only minor modifications to the design of existing turbine and generator assemblies.
FIG. 5 illustrates an alternative embodiment having a flattened central outlet tube that may be used where minimal excavation is desired. Like the central outlet tube 40 , the flattened central outlet tube 50 comprises a turbine 51 having turbine blades 52 and a generator nacelle 53 , all elements being designed to accommodate the shortened dimensions of the flattened central outlet tube 50 . The air flow is introduced by an inlet tube 21 having a flattened profile, such as those exemplified by the inlet tubes in FIGS. 7 and 8 having an oval cross section, or by those exemplified by the inlet tubes in FIGS. 9 and 10 having a rectangular cross section. In FIG. 7, the oval inlet tube 21 has a support 71 to provide structural integrity to the tube, and an adjoining duct 72 which allows tubes to be connected together and arranged without resorting to customized bending, etc. FIG. 8 shows the oval inlet tube 21 of FIG. 7 without the adjoining duct 27 . FIG. 9 shows a rectangular inlet tube 21 with a rectangular cross section having an adjoining duct 72 . FIG. 10 shows the rectangular tube of FIG. 9 having a support 71 , but without the adjoining duct 72 . One particular advantage of the tube sections shown in FIGS. 7-10 is that these sections can actually be manufactured as individual modular components so that they could be cast in concrete or extruded from recycled plastic and transported to the site by truck. Note that the central outlet tube 40 containing the turbine and generator assembly could be similarly precast in pie-shaped slices and transported to the site for assembly. These low-profile components could greatly reduce installation costs. It may even be possible to assemble them right on the ground and build a small berm around them, eliminating the requirement for digging altogether.
In FIG. 6, one preferred embodiment for the collector assembly 60 comprises a frame having a vertical mast 61 and a braced, wheel-like boom 64 used to help shape the sail 62 and transfer loads to the wall 66 of the inlet tube 21 by way of a sub-frame 65 . This arrangement allows the mast 61 , boom 64 , and sail 62 to spin freely around a vertical axis, much like a weather vane on its mount, and helps assure that when the sail is fully deployed, the collector assembly 60 will always face the wind.
The sail 62 covers an arc of approximately 180° across the rim 67 of the inlet tube 21 . The purpose of the collector assembly 60 is to capture ambient breezes and redirect them into the inlet tube 21 . The sail area for each collector assembly 60 should be greater than the cross-sectional area of the inlet tube 21 for the system to work efficiently. Because the cut of the sail 62 will determine the final shape of the working surfaces of the collector assembly 60 , on-site fine tuning of the optimal collector shape will be practical long after the initial installation has been completed. Sails 62 can be easily cut into a wide variety of shapes to take advantage of prevailing local wind conditions, making it a relatively simple matter to implement improved collector designs in a cost-efficient manner. Although the sails 62 will most likely have to be replaced every year or so, the cost of replacement would be a tiny faction of the costs typically incurred during the normal operation of a conventional fuel burning plant, such as the costs of fuel, emission control, maintenance, and toxic waste disposal.
In order to prevent damage to the collector assemblies 60 during storms and other high wind situations, the collector assemblies 60 comprise a mechanism for managing wind loads. FIGS. 11 and 12 show a preferred embodiment for this mechanism comprising a spring loaded, damped, drum-style tensioner 120 having two lengths of wound cable 121 , preferably made of steel for strength. The cable 121 ends opposite the drum 122 are attached to the sail 62 , providing a constant tension on the sail and helping to maintain its optimal shape, in a manner similar to the operation of the spring loaded roller on a window shade. The cable ends are attached to the drum 122 on one end, and to grommets 123 on the sail 62 , possibly using hooks, on the other end.
As the wind load on the system increases past that needed for peak output of the turbine, pressure on the sail 62 increases and the tensioning cables on the drum 122 begin to unwind, causing the sail 62 to move in an upward direction, which creates a gap between portions of the sail 62 and between the sail 62 and the braced boom 64 , causing air to spill through the back of the collector assembly 60 . This mechanism provides adequate wind load management in all but the most violent weather. In an alternative embodiment, the tensioner could utilize counterweights in a gravity powered sail tensioner in place of the springs to maintain tension on the sail 62 .
FIGS. 13 and 14 show an alternative embodiment for the tensioner utilizing a flexible rod assembly to maintain tension on the sail 62 . A fixed track 80 is mounted along one spoke of the braced boom 64 . A traveler 81 is affixed to the midpoint of a flexible tensioning rod 83 and is mounted on the fixed track 80 and can slide along the fixed track 80 from the mast 61 to a traveler stop 82 . Roller guides 84 affixed to the braced boom 64 restrict the movement of the ends of the tensioning rod 83 . Flexible lines 85 are affixed on one end to the traveler 81 , run through a line guide 86 affixed to the rim of the braced boom 64 , and are attached on the other end to the bottom of the sail 62 . As load on the sail 62 increases, tension on the lines 85 will cause the tensioning rod 83 to flex, allowing the bottom of the sail to move upward creating a gap A between portions of the sail 62 and a gap B between the sail 62 and the braced boom 64 , allowing air to spill through the back of the collector assembly 60 .
FIGS. 15 and 16 depict another alternative embodiment of the tensioner using a spring 87 affixed to the mast 61 to maintain tension on the sail 62 . Flexible lines 88 run from the spring 87 , through the line guide 86 and are attached to the bottom of the sail 62 . FIGS. 17 and 18 depict another alternative embodiment of the tensioner using elastic cords 91 to maintain tension on the sail 62 . The elastic cords 91 are affixed on one end to the mast 61 , run through the line guide 92 , and are attached to the bottom of the sail 62 .
According to FIG. 3, if wind loads increase past the point where they could be managed by the tensioning mechanism, an emergency strain relief system may be provided under critical load conditions. When such a situation occurs, the wind powered generator device may employ an emergency sail collector 30 comprising a collector loop 31 attached to a sock-like piece of sailcloth 32 at the top of the mast 61 . This sock 32 operates as a sail cover and is basically a cloth tube which is deployed and functions in a manner similar to an umbrella cover.
When the strain on the collector assembly 60 reaches some predetermined critical point, the collector loop 31 falls or is pulled down the mast 61 on a collector loop track 33 (which runs the full length of the front of the mast 61 , where the assembly is free to move without fouling the sails), taking the sock 32 with it and effectively dousing the sail. The collector loop 31 collects the sail as it travels down the track 33 and pulls the sock 32 along with it, thus relieving pressure on the collector assembly 60 . The collector loop 31 ring release may be tripped either mechanically, (for instance, by a mechanical load sensor attached to the sail tensioners and connected by cable to a release at the top of the mast), or electronically (for instance, by radio signal transmitted to the release when the site anemometer detects a predetermined wind level). Likewise, the collector loop 31 could be motivated by gravity, using a weighted ring, or electrically, using an electric motor to pull the ring down the track. A reset of the collector loop could be achieved manually by way of cables and pulleys (much like a traditional sail), or by electric motor. An electrically operated system could be reset remotely or in an automated manner. Although this action takes take the generator off line, it provides substantial protection to the collector assembly 60 against permanent damage. Since the collector loop 31 is only deployed under critical load conditions, it would rarely cause a shutdown of the system.
FIG. 19 shows another preferred embodiment in which a steering sail 68 is provided that is oriented in a direction perpendicular to the sail 62 . The steering sail 68 permits improved sensitivity and response time of the collector assembly 60 without adding drag to the system.
FIG. 1 shows a typical installation using a wind-thermal hybrid, with heat for a liquid thermal transfer medium, which is preferably non-toxic, supplied by conventional solar collectors 11 . Unlike conventional geothermal power plants, no steam is required to provide turbine boost, so areas which are now volcanically active but produce insufficient heat to produce steam could easily provide more than enough heat energy to boost the efficiency of this system. FIG. 4 illustrates a preferred placement of heat radiating surfaces/elements 44 within the main tube.
FIG. 20 shows an alternative embodiment of the wind powered generator device. Airflow captured and redirected by the collector assembly 60 is accelerated as it passes a turbine assembly 103 located in the narrowed center 102 of a tube 101 . Exhaust vents 104 provide a path for the airflow to escape after it has passed the turbine assembly 103 . A deflector ring 105 redirects ground level winds into the collector assembly 60 and away from the exhaust vents 104 , helping to prevent a buildup of pressure at the windward side of the exhaust vents from impeding the flow of air through the system.
The above-described wind-powered generating device is illustrative of the principles of the present invention. Numerous modifications and adaptations thereof will be readily apparent to those skilled in this art without departing from the spirit and scope of the present invention. | A wind powered generating device comprises a tube cluster, a collector assembly, and a turbine assembly. The collector assemblies utilize sails that can be rotated to direct wind down through an inlet tube to a central outlet tube. The central outlet tube is narrowed at a portion, and a turbine is mounted at this narrowed portion to take advantage of the Venturi effect that accelerates the air as it passes the turbine. This permits reliable and efficient operation in areas that were not formerly considered windy enough to be economically feasible for the deployment of wind powered generating devices. Alternative embodiments of the invention include mechanisms for dealing with violent weather conditions, a first of which allows excess wind to bleed off beneath and between the sails, and a second which collapses and covers the sail with a protective sheath/sock. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a wire reel stand and, more particularly, to a wire reel stand that may be folded into a compact arrangement for movement and storage.
2. Description of the Prior Art
Wire reel stands are used extensively in the building and trade industries as a relatively easy means for supporting a wire reel while unrolling the extensive lengths of wire that need to be run throughout a construction site. There exist in the art various types of reel supports that are used to facilitate the unwinding of the wire from the reel. Examples of such supports may be found in U.S. Pat. No. 2,601,960; 3,383,071; 4,391,422; and 4,746,078. A particular support arrangement that is collapsible when not in use is disclosed in U.S. Pat. 3,920,194, issued to E. M. Parsen on Nov. 18, 1975. The Parsen wire reel support comprises a set of three nested U-frames. When fully separated, the three frames form a "Y" configuration, with two arms used as ground support and the remaining arm used to hold the wire reel. In one particular configuration, each frame can hold a separate reel, such that three reels may be simultaneously loaded onto the support. Although the Parsen support can be described as an improvement over the state of the art, it may be subject to unwanted collapse, since a chain is the only means used to maintain the "open" configuration of the support.
SUMMARY OF THE INVENTION
A wire reel stand is disclosed that is capable of being folded into a compact configuration when not in use. The stand includes a pair of support leg members, of generally a "U" shape, attached at their ends to form an inverted "V" shape when separated. One of the support leg members includes a pair of angle irons attached to its end portions. The angle irons are permanently fixed such that when the pair of leg members are pulled outward into the "open" (i.e., inverted "V") position of the stand, the angle between the legs is fixed, supported and controlled. For example, an angle of approximately 70 degrees has been found to provide sufficient support for the stand structure, while allowing a large-sized reel to be attached to the support. Positioned between the open ends of the support leg members is a cross bar member. In the "open" position, the cross bar is used to support a wire reel. In the "closed" position, the cross bar becomes a convenient carrying handle for the stand. An additional cross bar member ("side bar") is releasably attached to each leg member. The side bar members may be attached to a support leg member at a first, relatively low position when not in use. The side bar member is attached at a second, higher position when used to support an additional wire reel or reels. The symmetry of the stand structure allows for each leg member to support a side bar member. In accordance with the present invention, the cross bar member and side bar members remain attached to the stand when closed, allowing for the complete assembly to be carried and stored as a single unit.
Other and further features of the present invention will become apparent during the course of the following discussion and by reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings,
FIG. 1 is an isometric view of the inventive wire reel stand, carrying a single wire reel (illustrated in phantom);
FIG. 2 is an isometric view of the wire reel stand in its "closed" position;
FIG. 3 is a side view of the wire reel stand in its "open" position, illustrated as carrying a wire reel on one of the side bar support members;
FIG. 4 is a cut-away view in perspective of a section of FIG. 2, taken along line 4--4, illustrating in particular the attachment of the cross bar member to the stand using a pair of support members;
FIG. 5 is a view of a portion of one leg support, taken along line 5--5 of FIG. 3, illustrating in particular one of the side guards used to prevent a wire reel from inadvertently coming into contact with the stand; and
FIG. 6 is a view of an exemplary side cross bar attachment area, taken along line 6--6 of FIG. 3, illustrating in particular an exemplary releasable attachment configuration suitable for attaching side bars to the stand.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An exemplary wire reel stand 10, in its "open" position, is illustrated in FIG. 1. A conventional reel 12 is illustrated in phantom as being supported by stand 10. Stand 10 includes a pair of U-shaped frame support members 14 and 16. Frame support members 14 and 16 are positioned so that the middle section of each support member (designated 14A and 16A in FIG. 1) rests against the ground and the end legs of each "U" are joined to form (in a side view, such as that of FIG. 3) an inverted "V" structure. A pair of angle irons 18 and 20 are permanently attached to frame support 16 and are positioned to brace against support 14 in the open position. Angle irons 18 and 20 are chosen to provide the desired degree of opening between supports 14 and 16. For example, a 70° angle has been found to provide a sufficient opening for the present purposes. A pair of rod support members 22 and 24 are attached to the terminating ends of rods 14 and 16. Each rod support member includes an aperture so that a cross bar member 26 may be inserted through the apertures and used to support a reel, such as reel 12. Cross bar member 26 may be formed to comprise a length L greater than the width of the reel stand, where the additional length on either end is used as a handle when carrying the reel stand. A releasable attachment mechanism, such as a pair of spring clips, is used to fix bar member 26 between rod support members 22 and 24. Bar 26 may be a pipe or a solid rod, either being considered to provide sufficient support for a wire reel.
For the arrangement as depicted in FIG. 1, only a single reel is being supported. In this configuration, the side bar members are attached at a lower position that does not interfere with the rotation of reel 12 as wire is removed. Rod 14 includes two sets of location pins, a first, lower set 28 and 30, and a second, higher set, 32 and 34. A first side bar 36 is illustrated as releasably attached to lower pins 28,30 by means of a pair of apertures 28a,30a in bar 36 that fit over pins 28,30. For the particular illustrated embodiment, side bar 26 is releasably attached by using locking pins. One exemplary locking pin is illustrated in detail in FIG. 6. As shown, the pin includes a rotatable end portion that may be held in a first, coaxial position (that is, in line with the body of the pin) when it is desired to place a side bar over the pin. Once the side bar is in place, the end portion of the pin is rotated into a second, perpendicular position (that is, perpendicular to the body of the pin) so that the side bar cannot be inadvertently removed. It is to be understood that various other releasable attachment mechanisms may be used; for example, pins 28,30 could be threaded, and a nut (such as a wing nut) may be used to releasably attach side bar 36 to frame member 14. As long as the attachment is "releasable" such that the bar may be moved between a lower, unused position, and an upper position to serve as a reel-carrying rod, any appropriate attachment means may be used. A side bar member 42 is similarly attached to frame member 16 at a pair of lower pins 46,48, where frame member 16 also includes a pair of pins 49,50 that may be used to locate side bar member 42 at a second, higher position. A pair of side guards 51,53 are attached to frame 16 (or alternatively, may be attached to frame 14) and used to prevent the end faces of reel 12 from coming into contact with frames 14 and 16. The side guards will be described in detail below in association with FIG. 5.
A collapsed configuration of wire reel stand 10 is shown in FIG. 2. As mentioned above, an advantage of the collapsible stand arrangement of the present invention is that all of the pieces remain attached to the stand when closed, allowing for easy storage without losing any of the parts. In the closed position, frame members 14 and 16 are folded together. Rod support members 22 and 24 may be rotated slightly to one side so that cross bar member 26 rests off-center in the folded arrangement. FIG. 4 is an enlargement of this particular portion of the closed configuration, illustrating the location of frame members 14 and 16, as well as rod support member 22 and cross bar member 26. As shown, a spring clip is used to releasably attach rod 26 at support member 22 (a similar spring clip provides attachment of rod 26 at support member 24). Referring back to FIG. 2, side bar members 36 and 42 are attached to frame members 14 and 16, respectively. In the illustration, side bar member 36 is depicted as separated from pins 32 and 34 merely to illustrate the location of the associated apertures 32a,34a in bar 36 and illustrate the method of attaching side bar member 36 to frame 14. As in the other illustrations, and as clearly illustrated in FIG. 6, a pair of locking pins (i.e., each pin including a rotatable end portion) is used to attach side bar member 36 to frame 14 (as well as side bar 42 to frame 16). For storage purposes, side bar members 36 and 42 may be attached at either the lower position or upper position along the respective frame member.
FIG. 3 is a cut away side view of collapsible wire reel stand 10, configured to support a wire reel 44 (shown in phantom) on side bar 36 of frame support 14. It is to be understood that if the wire reels are relatively short, more than one reel may be supported on a single bar. For the particular arrangement of FIG. 3, side bar 42 remains in its lowered, unused position. However, it is possible for both side bar members to simultaneously support reels, since the separation between frame supports 14 and 16, as controlled by angle irons 18,20 is sufficient to keep the reels on each side of the stand from touching each other.
As mentioned above, reel stand 10 may further include a pair of side guards 51 and 53, fixed to each leg portion of frame 16 (or alternatively, on frame 14). As shown in FIGS. 1 and 5, side guards 51 and 53 are disposed to protrude a predetermined distance into the interior region of stand 10. FIG. 5 contains an enlarged view of side guard 51 and its relationship to spool 12. In general, as the wire is unwound from the spool, the spool will "travel" back and forth between the ends of the stand. The amount of movement will, of course, be a function of the length of the spool as related to the length of the support bar. Side guards 51 and 53 serve to protect the ends of the reel from coming into direct contact with stand 10. Referring to FIG. 5, guard 51 protrudes beyond frame 16 by an amount d sufficient to maintain a space between frame 16 and reel 12.
It is to be understood that although this invention has been described by reference to preferred embodiments, various modifications in shape, size, arrangement of parts and materials may be resorted to without departing from the spirit or scope of the invention and these modifications are meant to be covered by the appended claims. | A wire reel stand that is capable of supporting multiple wire reels in its open position and is easily collapsed for storage. The stand includes a pair of "U"-shaped frame supports, with a central wire reel support rod disposed between the open ends of the frame supports. A pair of angle brackets, attached to one of the frame supports, is utilized to maintain the stand in a fixed, open position. Side bars are releasably attached to each frame member and, advantageously, remain attached to the wire reel stand in its closed configuration. | 1 |
PRIORITY
[0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 61/032,099 filed Feb. 28, 2008.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to doctor blade holders, and is concerned in particular with an improved design that facilitates holder sheet shedding, and water or debris removal performance while maintaining desired doctor blade holder performance.
[0004] 2. Description of the Prior Art
[0005] Many roll cleaning and sheet shedding applications on paper machines and other web handling applications involve blade support devices commonly referred to as doctor blade holders. Typically, a doctor blade holder is mounted on a doctorback which is a heavy-duty beam that spans the paper machine width. The rear portion of a doctor blade is received into the holder which supports the blade in a pre-determined position relative to a surface to be cleaned. The holder works in concert with the doctoring assembly to apply the working edge of the blade, found on the blade's front portion, to an adjacent moving surface.
[0006] U.S. Pat. No. 6,491,791 discloses a method and apparatus to clean roll surfaces or fabrics used in papermaking machines, wherein a doctoring element (4) includes one or two integral doctor blades (9, 9A) as well as an integral gas chamber (50) that provides pressurized gas, e.g., compressed air, to the outgoing side of a doctoring apparatus having one doctor blade (9), and to the inter-blade area of a doctoring apparatus having two doctor blades (9, 9A). The compressed air is provided to enhance the water or dirt removal capabilities. Each of the disclosed apparatus involves doctor blades that are integral with the structure forming the gas chamber within the doctoring element. The example of a two blade doctoring element, for example, provides that the interblade space forms a closely and tightly delineated pocket into which compressed air may be passed (col. 3, lines 18-20). The high pressure compressed air in an example, escapes under the doctor blades via grooves on the grooved-shell roll being processed (col. 6, lines 59-63). The use of such integral doctor blades requires that the entire doctoring element be replaced whenever the doctor blades become too worn. The doctoring apparatus are also not disclosed to be position adjustable with respect to the roll, and it is not at all clear how such an integral gas chamber may be incorporated in a doctoring apparatus that provides adjustable position accuracy with respect to a roll as well as flexibility in doctoring a roll along an elongated length of the doctor blade.
[0007] U.S. Pat. No. 6,139,638 discloses a doctor blade holder apparatus that includes a planar upper holding member that is pivotally mounted to a tray such that the position of the upper holding member (34) with respect to the tray (26) may be adjusted by unloading and loading tubes (30, 32). The upper holding member (34) also includes a plurality of distribution passages (60) that are coupled respectively off of the upper holding member (34) via a plurality of branch conduits (62) to a common header (64). The apparatus requires therefore, that the plurality of branch conduits (62) be provided along the elongated length of the holding member (34), which adds to manufacturing costs and complexity. Moreover, the pressurized fluid must maintain sufficiently equalized pressure as it travels through the separate conduits (62) as the fluid is directed toward the roll along the elongated length of the doctor blade.
[0008] There remains a need, therefore, for a doctor blade holder system that facilitates consistent debris removal without limiting the flexibility of the doctor blade holder system or the effectiveness of the doctoring process.
SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide a doctor blade holder specifically designed to apply pressurized fluid to assist in the detachment of a paper web from a roll surface and convey the web away from the roll.
[0010] Another object is to integrate the one or more fluid delivery systems into the holder body in a manner that serves the design intent of a well managed web exit from its detaching point.
[0011] Another object is to integrate within the same holder body additional pressurized fluid delivery means and directing said fluid to the area near the blade-roll contact line in order to remove debris that is known to accumulate there.
[0012] Another object is to provide within the holder body fluid jets designed to evacuate the water or debris dislodged from the cleaned surface.
[0013] Another object is to provide doctor blade holders that provides for effective fluid delivery onto the doctor blade yet also facilitates the replacement of worn doctor blades.
[0014] Another object is to provide within the holder design a two-tube blade loading and unloading system familiar to paper machine operators and easily integrated with pre-existing equipment.
[0015] Another object is to incorporate groups of one or more holder components into formed pieces via extrusion processes thereby reducing assembly part counts and associated labor, as compared to the multiple part assembly processes of certain prior art holders.
[0016] Another object is to provide additional cross-machine flexibility by sectioning the rotating portion of a full-length holder into a multiplicity of shorter cross-machine pieces that may be assembled individually and/or together with the doctor base piece to form a segmented full-length holder assembly.
[0017] The invention provides a doctor blade holder that includes a first member, a second member position adjustment elements, and fluid assisted cleaning elements. In accordance with an embodiment, the first member includes an elongated edge that is adapted for receiving a doctor blade, and the second member is movably coupled to the first member. The second member is secured to a doctor back. The position adjustment elements are for adjusting the relative position of the first member and the second member. The fluid assisted cleaning elements are for providing pressurized fluid to an area near an elongated edge of the doctor blade. The fluid assisted cleaning elements include at least one plenum within the first member.
[0018] In accordance with another embodiment, the first member includes an elongated edge that is adapted for receiving a doctor blade, and the second member is movably coupled to the first member by pivotal coupling structure that includes at least a portion thereof that is integrally formed with the first member. The second member is secured to a doctor back. The position adjustment elements are for adjusting the relative position of the first member and the second member. The position adjustment means includes a portion that is secured to the first member by mounting structure that is integrally formed with the first member. The fluid assisted cleaning elements are for providing a first pressurized fluid to a leading edge side of an elongated edge of the doctor blade. The fluid assisted cleaning elements include a first plenum within the first member.
[0019] In accordance with a further embodiment, the first member includes an elongated edge that is adapted for receiving a doctor blade. The second member is movably coupled to the first member and is also secured to a doctor back. The position adjustment elements are for adjusting the relative position of the first member and the second member. The position adjustment elements include at least one fluid expandable reservoir that causes the relative position of the first and second members to be changed when fluid is introduced into the fluid expandable reservoir. The fluid assisted cleaning elements are for directing a first pressurized fluid onto a leading edge side of an elongated edge of the doctor blade. The fluid assisted cleaning elements include a first plenum within the first member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The following description may be further understood with reference to the accompanying drawings in which:
[0021] FIG. 1 is an illustrative diagrammatic side view of a doctor blade holder in accordance with an embodiment of the present invention attached to a doctorback;
[0022] FIG. 2 is an illustrative diagrammatic enlarged side view of the doctor blade holder of FIG. 1 ;
[0023] FIG. 3 is an illustrative diagrammatic isometric view from above of a portion of the doctor blade holder of FIG. 1 ;
[0024] FIG. 4 is an illustrative diagrammatic cross-sectional view of the doctor blade holder of FIG. 3 taken along line 4 - 4 thereof;
[0025] FIG. 5 is an illustrative diagrammatic exploded isometric view from below of the doctor blade holder of FIG. 1 ;
[0026] FIG. 6 is an illustrative diagrammatic sectional view of an enlarged portion of the doctor blade holder of FIG. 5 ;
[0027] FIG. 7 is an illustrative diagrammatic isometric view from above of a doctor blade holder in accordance with an embodiment of the invention shown without the doctor blade and cover elements;
[0028] FIG. 8 is an illustrative diagrammatic isometric view from above of the doctor blade holder of FIG. 7 including the doctor blade and a plurality of cover elements.
[0029] FIG. 9 is an illustrative diagrammatic cross-sectional view of a doctor blade holder of another embodiment of the invention similar to the view shown in FIG. 4 of the first embodiment; and
[0030] FIG. 10 is an illustrative diagrammatic sectional view of an enlarged portion of the doctor blade holder of FIG. 9 ;
[0031] The drawings are shown for illustrative purposes only.
DETAILED DESCRIPTION
[0032] The present invention incorporates one or more fluid supply plenums for piping fluid into the body of the holder. The supply piping system distributes pressurized fluid to one or more nozzles arrayed along the holder in an elongated direction. The pressurized fluids may be used to assist the doctor blade holder in the detachment of a paper web from a roll surface; to shower the doctor blade generally, or particularly in the area near the blade-to-surface contact line; or to dislodge water or debris from process surfaces such as grooved or drilled rolls.
[0033] As shown in FIGS. 1 and 2 , a doctoring apparatus including a doctor blade holder 10 in accordance with an embodiment of the invention includes a first member 12 that is pivotally mounted on a second member 14 such that limited pivotal rotation is permitted with respect to an axis A 1 . As shown in FIG. 2 , the pivotal rotation is provided by an integrally formed pivotal coupling structure such as continuous rounded male portion 16 on the second member that is received within an integrally formed pivotal coupling structure such as continuous socket portion 18 on the first member. In other embodiments, an integrally formed continuous male portion may be provided on the first member, with an integrally formed continuous socket portion being provided on the second member. The first member 12 receives a doctor blade 30 along an elongated edge of the first member 12 , and the second member 14 is attached to a beam 19 that is attached to a doctor back 20 . The rotational position of the first member with respect to the second member is provided by inflatable loading and unloading reservoirs such as tubes 22 , 24 . Pivotal rotation of the doctor back 20 is provided by a piston 26 that is coupled to a crank arm 28 to provide rotation of the doctor back 20 with respect to an axis A 2 that is parallel to the axis A 1 .
[0034] As also shown in FIG. 2 , the first member 12 includes a cap 32 and a body 34 , and the doctor blade 30 is received between a portion of the cap 32 and the body 34 , and may be held in place by an optional spring element 36 . The doctor blade 30 may be readily replaced as desired, for example, when the doctor blade becomes worn, without replacing the entire doctoring apparatus. As a roll 38 rotates about an axis A 3 , the doctor blade 30 is applied to the roll. Plenums 40 , 42 within the body 34 of the first member 12 are defined by walls that are integrally formed with the first member, and contain pressurized fluid, such as air or water, that are applied to the doctor blade 30 during processing as discussed in more detail below. Each plenum may provide the same fluid or may provide different fluids. The cap 32 and body 34 are joined together using fasteners 44 that are received within apertures 46 in the cap 32 and are secured to the body 34 .
[0035] The first member 12 and second member 14 are formed preferably by extrusion or pultrusion, from metal, such as stainless steel alloys such as 300 series, or aluminum alloys such as series 6000. Aluminum alloys are preferably treated with one or more protective coatings well known to those skilled in the art. The cap 21 may alternatively be comprised of a multiplicity of short pieces, extruded or cast from above mentioned alloys, the multiple cap pieces being attached to the rotator 22 is the same manner as for the single, elongated cap. In further embodiments, the members 12 , 14 may be formed of high temperature resistant polymeric materials or resins, and may include filler material such as fiberglass, ceramic and/or metallic materials.
[0036] With further reference to FIGS. 3 and 4 , air is provided to the inflatable loading and unloading tubes 22 , 24 via conduits that may be provided at one or both ends of each of the tubes 22 , 24 . At least one of the tubes (e.g., 24 as shown in FIGS. 2 , 4 and 5 ) may be mounted to the first member 12 by mounting structure 25 that is integrally formed with the first member 12 . Pressurized fluid, such as compressed air, is provided to the doctoring apparatus via a conduit coupled to the plenum 40 , and another fluid, such as water, is provided under pressure within the plenum 42 via a conduit as well. Each of the plenums 40 , 42 may be coupled to such conduits at one or both ends of the doctoring apparatus.
[0037] As shown in FIG. 5 , the compressed air from within the plenum 40 travels out of the plenum 40 and toward the blade 30 via ports 47 that lead to a plurality of passages 48 formed between the cap 32 and a guide plate 50 on the body 34 . The guide plate 50 directs the compressed air onto the leading edge side 52 of the blade 30 as the roll 38 rotates. A flush fastener 54 is employed to secure the guide plate 50 to the body 34 .
[0038] As shown in FIG. 6 , the fluid under pressure from the plenum 42 (such as water or air) travels out of the plenum 42 and toward the blade 30 via a flood fan nozzle 56 , which as shown in FIG. 4 , directs the water stream toward the trailing edge side 58 of the blade 30 as the roll 38 rotates.
[0039] As shown in FIGS. 7 and 8 , multiple caps 32 are provided along the body 34 , in an elongated direction as shown at 60 , and each cap 32 includes a passage that aligns with a port 47 of the continuous plenum 40 in the body 34 . Each cap 32 is secured to the body 34 by fasteners 44 within apertures 46 of the caps 32 .
[0040] FIGS. 9 and 10 show a doctor blade holder 70 in accordance with another embodiment of the invention that includes a first member 72 that is pivotally mounted on a second member 74 such that limited pivotal rotation is permitted with respect to an axis A 4 . The pivotal rotation is provided by an integrally formed pivotal coupling structure such as a continuous rounded male portion 76 on second member that is received within an integrally formed pivotal coupling structure such as a continuous socket portion 78 on the first member. In other embodiments, an integrally formed continuous male portion may be provided on the first member, with an integrally formed continuous socket portion being provided on the second member. The first member 72 receives a doctor blade 90 along an elongated edge of the first member 72 . The rotational position of the first member with respect to the second member is provided by inflatable loading and unloading reservoirs such as tubes 82 , 84 . The second member is attached to a doctor back as discussed above with reference to FIG. 1 , and pivotal rotation of a doctor back is provided by a piston that is coupled to a crank arm to provide rotation of the doctor back.
[0041] The first member 72 includes a cap 92 and a body 94 , and the doctor blade 90 is received between a portion of the cap 92 and the body 94 , and may be held in place by an optional spring element 96 . As the roll 38 rotates, the doctor blade 90 is applied to the roll. Plenums 100 , 102 within the body 94 of the first member 72 are defined by walls that are integrally formed with the first member 72 , and contain pressurized fluid, such as air or water, that are applied to the doctor blade 90 during processing. The cap 92 and body 94 are joined together using fasteners 104 . The first and second members 72 , 74 are formed as discussed above with reference to FIGS. 1-8 .
[0042] Air is provided to the inflatable loading and unloading tubes 82 , 84 via conduits as discussed above. At least one of the tubes (e.g., 84 as shown in FIG. 9 ) may be mounted to the first member 72 by mounting structure 85 that is integrally formed with the first member 72 . Pressurized fluid, such as compressed air, is provided to the doctoring apparatus via a conduit coupled to the plenum 100 , and another fluid, such as water, is provided under pressure within the plenum 102 via a conduit as well as also discussed above. Each of the tubes 82 , 84 and the plenums 100 , 102 may be coupled to such conduits at one or both ends of the doctoring apparatus.
[0043] The compressed air from within the plenum 100 travels out of the plenum 100 and toward the blade 90 via ports 107 that lead to either a plurality of passages (such as shown at 48 in FIG. 5 ) or a single elongated passage 108 formed between the cap 92 and a guide plate 110 on the body 94 . The guide plate 110 directs the compressed air onto the leading edge side 112 of the blade 90 as the roll 38 rotates. A combined fastener and flow restrictor 114 is employed to secure the guide plate 11 to the body 94 , as well as to controllably restrict the flow of compressed gas within the passage 108 .
[0044] The water under pressure from the plenum 102 travels out of the plenum 102 and toward the blade 90 via a bidirectional nozzle 116 that via a first opening 120 directs a first water stream toward the trailing edge side 118 of the blade 90 as the roll 38 rotates, and via a second opening 122 directs a second water stream onto the roll 38 . The first and second water streams may be, for example, 90-120 degrees from one another.
[0045] Doctoring assemblies including doctor blade holders of various embodiments of the invention permit the doctor blade to provide the requisite structural and mechanical properties for processing the roll, while also permitting a first fluid to be directed toward a leading edge side of the blade, and permitting a second fluid to be directed toward a trailing edge side of the blade during processing or the roll.
[0046] Those skilled in the art will appreciate that numerous modifications and variations may be made to the above disclosed embodiments without departing from the spirit and scope of the invention. | A doctor blade holder is disclosed that includes a first member, a second member position adjustment elements, and fluid assisted cleaning elements. The first member includes an elongated edge that is adapted for receiving a doctor blade, and the second member is movably coupled to the first member. The second member is secured to a doctor back. The position adjustment elements are for adjusting the relative position of the first member and the second member. The fluid assisted cleaning elements are for providing pressurized fluid to an area near an elongated edge of the doctor blade. The fluid assisted cleaning elements include at least one plenum within the first member. | 3 |
FIELD OF THE INVENTION
This invention relates to a modular unified floor assembly suitable for towed transport from a manufacturing facility to the site where it is to be used, and more particularly to such a unified floor assembly which incorporates a cost-efficient longitudinal wooden girder beam and provides an optional preformed reinforced stairway opening.
BACKGROUND OF THE RELEVANT ART
A variety of unified floor assemblies, incorporating varying amounts of wood and steel and suitable for specific purposes, are known. These include manufactured unified floor assemblies, of a type readily towed on public highways to a selected site for use, as taught in my patents U.S. Pat. Nos. 4,930,809, 5,028,072, and 5,201,546.
The goal is to provide an economically-manufactured, strong but light, conveniently transportable floor assembly which can be cooperatively mounted on site with one or more other similar floor assemblies as part of a building structure. There are numerous advantages in manufacturing floor assemblies in this manner, including uniform quality control, economies of scale in manufacture, optimum utilization of skilled and trained manpower, and the facility for precisely customizing product to suit the needs of individual customers. The use of lengthwise steel beams in such floor assemblies provide strength but may add to the weight and costs more than wood. It is therefore desirable to minimize the use of steel in such floor assemblies. This is best accomplished by judiciously combining wood and steel.
One increasingly common use for such manufactured floor assemblies is in forming the ground level floors of building structures that have basements. It is not uncommon nowadays to have each floor assembly of fairly large size, e.g., such as to provide a useful floor area of the order of 14 ft.×40 ft. or longer. The resulting floor structures typically are supported either on upright basement walls or on metal or masonry posts disposed where two immediately adjacent floor assemblies come together and are connected to provide a large continuous useful floor.
Such floor assemblies typically provide a floor at an upper surface and also a lower surface which can inherently serve as a ceiling for the basement portion of the finished structure. As in all floors, there is in such floor assemblies a vertical spacing between the uppermost horizontal surface which serves as the floor for the space above the floor assembly and the lowermost horizontal surface which usually serves as the ceiling for the basement portion of the finished structure. By suitable selection of the dimensions of this space it becomes possible during the process of manufacturing the floor assembly to include ventilation ducting, piping, electrical power telephone lines, wiring, and the like, for easy connection to sources of warm or cold air, hot or cold water, and the usual electrical power and telephone lines from outside, respectively.
Uniformity of the finished product and high quality control are readily realized where the manufacturing of the floor assembly and its innards takes place under a roof rather than in the open as is common in forming floor structures on site in the open and when exposed to inclement weather conditions.
As noted, for different needs it is desirable to have particularized structural features. One such need is for a floor assembly having a precisely-dimensioned preformed opening for the location of a stairway. As persons of ordinary skill in the art will appreciate, the formation of such a hole in a floor assembly of conventional type can generate a structural weakness which can become a serious problem when the manufactured floor assembly is towed at typical highway speeds over uneven road surfaces. Such an opening must therefore be properly reinforced when the floor assembly is manufactured, i.e., before it is towed away.
There is, therefore, a clear need for a lightweight, reasonably priced, modular floor assembly which allows an architectural designer to specify an opening for a stairway leading downwardly from the floor on site. The present invention is particularly suited to meet this need.
SUMMARY OF THE INVENTION
Accordingly, it is a principal object of this invention to provide in a preferred embodiment a unified floor assembly employing a relatively long, lightweight, strong, longitudinal wooden girder beam.
It is a related object of this invention to provide a modular unified floor assembly which is lightweight, strong and reasonably priced, and which incorporates a lengthwise wooden girder beam formed to facilitate cooperating disposition in use with another similar modular floor assembly to generate extensive floor structures with provision for ventilation ducting, piping and wiring included within.
It is another object of this invention to provide a lightweight, economically-manufactured, unified floor assembly which includes a preformed opening for a stairway.
These and other related objects of this invention are realized by providing a modular unified floor assembly having a longitudinal axis, which includes a longitudinal first interior beam means parallel to the longitudinal axis for providing interior support and a longitudinal second interior beam means also parallel to the longitudinal axis and on an opposite side thereof relative to the first beam means, for providing additional interior support. The floor assembly also includes an exterior longitudinal rail means which is disposed parallel to the longitudinal axis and provides longitudinal support and defines a first longitudinal perimeter portion of the floor assembly. A longitudinal girder beam having numerous openings to accommodate utility elements and to reduce weight is disposed parallel to the axis and on an opposite of the floor assembly to the rail means, for providing longitudinal support and defining a second longitudinal perimeter portion of the floor assembly. The structure also includes a plurality of transverse truss means each connected to the side rail means at a first end, to the girder beam at a second end, and to the first and second interior beam means respectively intermediate the first and second ends.
In another aspect of this invention, the floor assembly as described in the immediately preceding paragraph is modified by making the second interior beam means in two collinear portions separated by a first gap corresponding to a longitudinal side of a stairwell disposed therebetween, and in the plurality of transverse truss means including at least one shortened truss means which extends from a first end connected to the rail means, past the first interior beam means and connected thereto, to a second end which is intermediate the first and second beam means, the second end being separated from the girder beam by a second gap corresponding to a transverse side of the stairwell disposed therebetween.
To obtain extensive floor assembly structures, two of the above-described unified floor assemblies may be disposed in use so that their respective girder beams are immediately adjacent and connected to each other, the combined unified floor assemblies being supported underneath so that they are horizontal and at the same level.
In yet another aspect of this invention, each of the above-described unified floor assemblies has its girder beam formed so that it has a gap of selected width and length defined at a first end and an extension of corresponding width and length at an opposite end. Two such unified floor assemblies may be longitudinally connected to each other with the extension at the end of the girder beam of one unified floor assembly being fitted into the corresponding gap in the girder beam of the second unified floor assembly. Then, with the two unified floor assemblies each supported to be horizontal and at the same level, the combination of the two unified floor assemblies provides an extensive longitudinal combined floor assembly.
Persons of ordinary skill in the art can be expected to consider these and other equally obvious and advantageous ways of combining and supporting two or more such unified floor assemblies to suit particularized needs, e.g., for L-shaped floors, etc., upon understanding the detailed disclosure of the invention as provided below with reference to the accompanying drawing figures.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a fragmentary perspective view of a unified floor assembly partially supported along outer edges by vertical structural walls and supported elsewhere by an exemplary support post.
FIG. 2 is a partial perspective view of two side-by-side cooperating unified floor assemblies according to a preferred embodiment of this invention, one of the floor assemblies being manufactured with a rectangular, reinforced stairway opening.
FIG. 3 is a partially-exploded vertical cross-sectional view of the principal elements forming a transverse truss in the unified floor assembly according to the preferred embodiment of FIG. 2.
FIGS. 4, 5, and 6 are respective enlarged views illustrating structural details of how certain transverse elements are joined to lengthwise elements in the preferred embodiments.
FIG. 7 is a vertical side elevation view of a transverse chord incorporated at an upper portion of a truss the floor assembly according to the preferred embodiments.
FIG. 8 is a partially-exploded perspective view to illustrate details of an elongate girder beam and the manner of its disposition relative to transverse elements in the preferred embodiments.
FIGS. 9, 10, 11 and 12 are enlarged views of various junctions between cooperating elements in the elongate wooden girder beam per FIG. 8.
FIG. 13 is a perspective view of an exemplary footing for a support post of a type suitable for supporting the unified floor assembly of this invention at locations away from supporting walls.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The floor assembly is conveniently manufactured at a central facility where cost efficiencies are realized and uniform quality controls are exercised over the manufacturing process. The floor assembly is then mounted to a suitable wheeled carriage structure of known kind and towed behind a tractor vehicle over highways with the normal amount of shock-loading experienced in transit. A primary goal, therefore, is to form the floor assembly such that even when a stairwell opening is formed therein during manufacture the floor assembly will cope with all foreseeable shock loads which it will encounter before coming to rest at its final destination.
One way to obtain high strength in a floor assembly, is to selectively employ properly proportioned steel elements. This adds to the weight and cost, hence sophisticated structural analyses are performed and steel elements for support are employed only in places and in a manner deemed optimum in light of all the factors, e.g., ease of manufacture, weight, cost, and anticipated loading both during transportation and in its ultimate use. Thus, for example, a floor assembly which is expected to ultimately support rather heavy machinery, equipment, heavily-loaded shelves, etc., may need heavyduty steel elements. By contrast, a relatively small floor assembly for use in the living room of a dwelling may require less steel. In short, the amount, physical dimensions, and overall strength of any metal elements used in the floor assembly according to the preferred embodiments of this invention must be chosen in light of such factors. Persons of ordinary skill in the mechanical arts can be expected to make the necessary choices and decisions in the exercise of their normal professional skills, hence any dimensions discussed below are intended to be exemplary and not as limiting.
FIG. 1 is a fragmentary perspective view of a unified floor assembly according to a first preferred embodiment of this invention. This floor assembly 100 has a generally rectangular form with its length along a longitudinal axis X-X being greater than its width measured normal to this axis. This, however, is not intended to be definitive or limiting, and square floor assemblies may be manufactured in accordance with the present invention. However, when a rectangular form is selected, the finished floor assembly will likely be towed in a direction along the axis X-X. As can be expected, unevenness of the road surface will cause up-and-down movement of the towed floor assembly, generating external and inertial forces principally in a vertical plane. This will tend to cause bending or flexing of the floor assembly in a vertical plane, i.e., the front and back ends of the floor assembly will tend to move up and down relative to their unstressed positions. It is therefore necessary to provide strong longitudinal internal support to counter foreseeable shock-loading during transportation of the floor assembly from the point of manufacture to its ultimate site of use.
Even when the floor assembly 100 reaches its final destination, and is supported as indicated in FIG. 1 by upright vertical support walls such as 102 and 104 positioned along its outermost edge portions, the need for strong longitudinal internal support remains. For this reason, it is preferable, although not absolutely necessary, to employ elongate I-section steel beams 106 and 108 disposed parallel to and on opposite sides of axis X-X. These beams in the embodiment per FIG. 1 will extend without interruption for substantially the entire length of the floor assembly 100 if no stairwell opening is formed. As described below with reference to FIG. 2, the formation of a stairwell opening requires the inclusion of reinforcing elements to ensure against undue stressing and structural damage during transportation of the floor assembly and its subsequent use.
As generally indicated in FIG. 1, one elongate side of floor assembly 100 has the form of a side wall 110 comprising a plurality of elongate wood elements 112,114 and 116 stacked in a vertical relationship. Side wall 110 rests on an elongate, flat, horizontal sill plate 118 disposed over upright support wall 102. Similarly, immediately below a transverse end portion of floor assembly 100 there is provided another sill plate 120 at the top of upright support wall 104.
On an opposite side from side wall 110 and parallel thereto, the longitudinal edge portion of floor assembly 00 comprises a unique elongate girder beam 122 which, like side wall 110, extends the entire length of floor assembly 100.
Transversely of side wall 110 and girder beam 122 disposed parallel thereto, there is provided a plurality of transverse trusses 124, parallel to each other and each preferably perpendicular to longitudinal axis X-X. Each of these transverse trusses is formed of a plurality of cooperating components which is described more fully hereinbelow.
Side wall 110 has an uppermost longitudinal surface 26, longitudinal girder beam 122 has an uppermost longitudinal surface 128, and transverse trusses 124 each have an upper surface 130. When floor assembly 100 is properly supported, surfaces 126,128 and 130 are all in a common horizontal plane upon which is affixed flooring 132 which provides a smooth upper floor surface. Simultaneously, by its common connection to side wall 110, girder beam 122 and trusses 124, flooring 132 stiffens and unifies the overall structure and may comprise plywood, masonite, metal, or other suitable known material.
Although not clearly shown in FIG. 1, a layer of wood, e.g., plywood, may also be affixed to the respective lowermost surface of side wall 110, girder beam 122, and trusses 124, and could serve as a ceiling surface for the space underneath floor assembly 100. A conventional false ceiling could be suspended beneath floor assembly 100.
As indicated in FIG. 1, additional support may have to be provided to floor assembly 100 at suitable locations beneath girder beam 122 along the corresponding longitudinal side of the floor assembly. Such support may take the form of upright support posts such as 133 each resting on a post support plate 134 provided on a floor 136 beneath floor assembly 100. At the top of support post 133 there is preferably provided a load plate 138 to extend beneath the lowermost surface of floor assembly 100 directly under longitudinal girder beam 122. The number and separation of such posts must necessarily be related to the total weight to be imposed upon floor assembly 100 and the necessary choices may be readily made by persons of ordinary skill in the mechanical arts as needed.
As generally indicated earlier, steel I-section beams 106 and 108 could, under appropriate circumstances, be replaced by I-section beams made of wood. However, for relative large floor assemblies according to this invention, it is preferable to employ steel I-section beams such as 106 and 108 in FIG. 1.
Although it is not very clearly seen in FIG. 1, it will be readily understood that trusses such as 124 may be readily utilized to define the transverse ends of floor assembly 100, e.g., over transverse sill plate 120 above support wall 104, and in similar manner at an opposite transverse end (not shown in FIG. 1 for simplicity).
As best seen in FIG. 2, assorted utility elements such as heating and/or air conditioning ducting 150, water pipe 152, and electric power and/or telephone wires 154, 156 may be installed within floor assembly 100 (or 200), at the time of manufacture, with conventional end fittings (not shown).
The floor assembly 100 illustrated in FIG. 1 includes no stairwell openings formed therein during manufacture. However, with some modification of the structure illustrated in FIG. 1 it becomes possible to provide another preferred embodiment, i.e., floor assembly 200, best seen in FIG. 2, which has a stairwell 202 formed therein during manufacture. Such a floor assembly 200 can be readily combined with a floor assembly 100 to provide an extended floor structure with a suitably located and sized stairwell 202. Note that floor assembly 200 is generally very similar to floor assembly 100, i.e., each has a longitudinal side wall or rail 110, a longitudinal girder beam 122 parallel thereto, a plurality of full width transverse trusses 124, and longitudinal interior beams 108.
Floor assembly 200, however, has a break in its interior longitudinal support beam 106. The two portions 106a and 106b are maintained to be collinear with each other and are separated by a distance corresponding to a dimension of stairwell opening 202 in a direction parallel to support beams 106a and 106b.
Correspondingly, at least one of the plurality of the transverse trusses 124 must be made shorter by an extent corresponding to a transversely-oriented dimension of stairwell opening 202. Such a shortened transverse truss 124s, like the other full width trusses 124, is joined to rail 110 (in a manner to be described in greater detail below), lies over the interior longitudinal support beam 108 and ends at and is connected to a reinforced longitudinally-oriented support element 204 which is itself connected at its ends to two reinforced transverse trusses 206 and 208.
The net consequence is that stairwell opening 204 is defined, as best seen in FIG. 2, by reinforced support element 204, reinforced transverse trusses 206 and 208, and at least a total thickness of the respective girder beams 122, 122 of floor assemblies 100 and 200 in the structure of FIG. 2. The reinforced support member 204 may be constituted of a double thickness of wood as illustrated in FIG. 2, and would have an uppermost surface parallel to that of guide rail 110 and the full width trusses 124. Similarly, the shortened truss 124s must be positioned so that its uppermost surface is parallel, i.e., coplanar, with the uppermost surfaces of side rail 110, full width trusses 124 and reinforced support element 204. The goal is to ensure that the flooring continues to be uniformly horizontal over the entire floor assembly 200 except for the stairwell.
Reinforcement of full width trusses 206 and 208 may be most readily realized by providing two trusses 124 side by side and firmly connected to each other, e.g., by nails or other suitable fastening elements.
In the structure illustrated in FIG. 2, comprising a floor assembly 100 (without a stairwell) and a floor assembly 200 (formed with a stairwell 202), the total thickness of the two girder beams 122, 122 provides the necessary reinforcement at the corresponding side of stairwell 202. However, to ensure that floor assembly 200 may be safely transported without suffering permanent damage due to transportation shock forces, a laminated beam 210 may be attached to that portion of girder beam 122 (of floor assembly 200) which corresponds to the stairwell. This laminated beam 210 may be of a width comparable to the vertical height of girder beam 122 and preferably has a length sufficient to extend past both sides of the stairwell to a distance sufficient to be attached to three adjacently separated successive full width trusses 124. The purpose of such a laminated beam 210 is two-fold: first, to ensure that there is added stiffness at the side of stairwell 202 corresponding to girder beam 122; and, secondly, to provide reinforcement where the double thickness, reinforced, full width trusses 206 and 208 connect to girder beam 122. It should be remembered that floor assembly 200 must be transported by itself to the final location and, therefore, that unless laminated beam 210 were thus provided the portion of girder beam 122 corresponding to the stairwell would be a singularly weakened point in the structure being transported. Persons of ordinary skill in the art would appreciate that the provision of laminated beam 210 of at least the dimensions discussed immediately above will not only strengthen floor assembly 200 around the stairwell but will add to the ability of the floor assembly 200 to withstand twisting or torque-related stresses which could well be encountered during transportation over uneven road surfaces.
The above-discussed reinforcement aspects are intended to be only exemplary, and persons of ordinary skill in the art upon becoming aware of the need to provide sufficient reinforcement can be expected to consider other alternatives, e.g., providing C-section metal channel members or the like in place of the second thicknesses of wood in support member 204 or full width reinforced trusses 206, 208. Such obvious variations are intended to be comprehended within this description, the principal goal being to ensure that even a relatively large floor assembly 200 can be transported safely so that it arrives to be used without suffering any loss of structural integrity or strength since its manufacture.
Referring now to FIG. 3, it will be seen how in the preferred embodiment the exemplary full width transverse truss 300 (intended to be structurally similar to the trusses 124) comprises an elongate chord 302 of a length corresponding to the total width of the floor assembly 100 or 200. Such a chord 302 preferably is made of wood in a length in the range 10 ft.--20 ft., and a cross-section preferably about 2 in.×6 in. It may be desirable to form dadoed cuts preferably not more than 5/8 in. deep and preferably not closer than 3 in. from the nearest point of either of I-section steel beams 106, 108. Such dadoed cuts 304 may be used to accommodate support boards for providing additional support and stiffness to the floor covering to be applied thereover.
I-section steel beams 106, 108 are preferably separated by a distance approximately 8 ft. apart. Just above the bottom flanges of longitudinal support beams 106, 108, each of the full width transverse trusses includes a C-section steel structural channel element 306 which may be welded or bolted at its ends to the respective upper surfaces of the flanges of beams 106, 108. Inclined bracing members 308, 308 may be welded or bolted in place as illustrated in FIG. 3 to ensure stiffness and strength in the transverse interconnection thus provided between I-beams 106, 108. As best seen in FIG. 3, on the side of truss 300 adjacent to longitudinal side wall 110 there is preferably provided a sheetmetal cross member 400 shown in greater detail in FIG. 4. Cross member 400 has an upper flange 402 which is affixed to an under surface of chord 302, e.g., by driving nails, screws or the like through apertures 404 provided therein. Cross member 400 also has a lower flange 406 parallel to upper flange 402, and a vertical web 408 therebetween. The ends of lower flange 406 and vertical web 408 may be attached to the corresponding immediately adjacent surfaces of I-support beam 106 by welding, bolting, or in any other suitable manner. At the end immediately adjacent to rail 110, cross member 400 is provided with vertical, longitudinally-oriented flanges 410, 410 affixed to a laminated beam 412, the respective dimensions being selected such that an outer vertical surface of laminated beam 412 is in the same vertical plane as the end of top chord 302 and allows affixation of laminated board 412 directly to an inside surface of side wall 110.
At the other end of full width transverse truss 300 there is provided a generally similarly structured, mirror-image type cross member 500 having an upper flange 502 provided with apertures 504, by which it is connected to an under surface of top chord 302, a bottom flange 506 and a vertical flange 508 which may be connected to corresponding immediately adjacent surfaces of I-support beam 108 by welding, bolting, or the like. Truss member 500 is also provided with end flanges 510, 510 formed with apertures 512 through which conventional nails, screws or the like may be applied or connected to inside surfaces of longitudinal girder beam 122.
As will be appreciated, when reinforcement beam 210 is provided as part of the reinforcement of girder beam 122 and stairwell opening 202, flanges 510 would be affixed thereto for reinforced trusses 206, 208 and immediately adjacent full width trusses 124 as previously discussed.
As best seen in FIG. 6, where top chord 304 passes over the top flanges of I-beams 106, 108, it is preferable to affix shear blocks 602 to provide reinforcement and additional stiffness. Shear blocks 602 may be affixed to top chord 302 with the corresponding truss 124 by nails or the like. See also FIG. 7 which clearly indicates that shear blocks 602 have a height corresponding to that of top chord 302 so that any flooring placed thereabove may be affixed to both the chord 302 and shear blocks 602 to thereby further stiffen and make the entire unified structure more rigid.
Details of longitudinal girder beam 122 are best understood with reference to FIG. 8. Girder beam 122 comprises a top elongate chord 802. If the length of the corresponding floor assembly, i.e., 100 or 200, is in excess of about 20 ft., it may not be possible to provide a single element continuous top chord 802. Separate cooperating or linear elements 802, 802 may thus be butted to each other at interfaces 804 and affixed to each other thereat by conventional nail plates such as 806.
Girder beam 122 also has an elongate longitudinally-oriented bottom chord 808 spaced from top chord 802 by spacer blocks 810 and cross bracing elements 812, 814. Various conventional nail plates, e.g., 816,818 and 820 may be employed as needed to affix these elements to each other in a strong and permanent manner.
The above-described construction of longitudinal girder beam 122 ensures that there are numerous openings therethrough to accommodate assorted utility elements, e.g., ventilation ducting 250 connectable to a floor register 252, pipes, wires, etc. The provision of these openings also reduces the total weight while the spacer blocks and bracing elements combine to provide the desired stiffness, strength and overall flexibility needed to accommodate the shock loads which the floor assembly 100 or 200 is expected to encounter during transportation.
There is yet another aspect of girder beam 122 which provides singular advantages in longitudinally combining and connecting successive floor assemblies 100 or 200. This feature is best understood with reference to FIGS. 8, 9 and 10. As best seen in FIG. 9, at one end of girder beam 122 top chord 802 ends short relative to the corresponding adjacent end of bottom chord 808. Instead of a single spacer block 810, there are provided two cooperating spacer blocks 902 and 904, of which spacer block 904 is longer and projects beyond the aligned ends of spacer block 902 and lower chord 808. The various spacer blocks and top and bottom chords of the same thickness, as best seen in FIGS. 8, 9 and 10, and are interconnected to each other by the use or conventional nail plates 906, 908. By the just-described structure, there is provided at one end of girder beam 122 a male projecting portion of spacer block 904.
At the opposite end of the same girder beam 122 an opening is left between top chord 802 and an upper surface of spacer block 902 which ends in alignment with bottom chord 808. Furthermore, top chord 802 extends beyond the immediately adjacent end of bottom chord 808 by an amount which corresponds to the longitudinal spacing apart between the ends of top chord 802 and bottom chord 808 at the opposite end of girder beam 122. There is thus created a female end to girder beam 122 shaped, sized and aligned to closely receive therein a corresponding male end of a girder 122 of the same thickness and belonging to another floor assembly 100 or 200 longitudinally aligned therewith.
Then, as indicated at the left-hand end of FIG. 8, when two longitudinal girder beams 122, 122 each belonging to a respective longitudinally aligned floor assembly are moved into engagement with each other the male and female elements fit closely and being of the same thickness may be affixed to each other by additional conventional nail plates (not shown for simplicity). When two floor assemblies are thus cooperatively connected to each other by their respective longitudinal girder beams 122, the flooring applied thereof may be disposed to further consolidate and unify the two floor assemblies by additional connecting nail plates or the like.
As persons of ordinary skill in the art will appreciate, in FIG. 2 there is illustrated and made clear how two floor assemblies, one of which may optionally have a stairwell, may be disposed to be unified at their immediately adjacent longitudinal sides. In similar manner, FIGS. 8-10 illustrate and make clear how to interconnect the respective longitudinal girder beams 122 of two cooperating floor assemblies in a longitudinal cooperative relationship. Persons of ordinary skill in the art can be expected to explore and consider other variations, e.g., employing three floor assemblies in a cooperative manner so as to create a L-shaped unified floor therefrom. Such variations are intended to be comprehended within the present invention.
FIGS. 11 and 12 indicate somewhat enlarged views of the above-discussed aspects, i.e., the manner in which spacer block 810, top chord 802, bottom chord 808, and inclined bracing elements 812 and 814 are interconnected to each other by nail plates 816, 818 and 820.
FIG. 13 is a perspective view illustrating an exemplary masonry or concrete-block footing structure which may be formed to support the lowermost end of a support post such as 132 if no preexisting floor 136 is available as in the structure illustrated in FIG. 1. Other alternative structures to accomplish this purpose may be considered to suit particularized needs. The goal is to ensure that there is sufficient load-bearing surface available beneath support post 132 to adequately support the anticipated weight to be received thereon from the floor assembly supported thereover, with an adequate factor of safety taken into account.
In this disclosure, there are shown and described only the preferred embodiments of the invention, but, as aforementioned, it is to be understood that the invention is capable of use in various other combinations and environments and is capable of changes or modifications within the scope of the inventive concept as expressed herein. | A lightweight, strong, economically-manufactured, and safely transportable modular unified floor assembly includes a lengthwise wooden girder beam formed with male and female ends to facilitate cooperative integration thereby to another similar floor assembly. In another aspect of the invention, the floor assembly is manufactured with a stairwell opening of selected size and at a selected location. The floor assembly even with a stairwell opening according to this invention is strong enough to be transported comfortably and safely from its point of manufacture to the site at which it is to be located for use. | 4 |
TECHNICAL FIELD
[0001] The present invention relates to holders used to attach a license plate to a motor vehicle, and more particularly to a universal license plate attachment system which accommodates differing sizes of license plates that are used in various locations around the world.
BACKGROUND OF THE INVENTION
[0002] Motor vehicle regulations around the world require that motor vehicles display a license plate indicative of the registration of that vehicle. The usual attachment of the license plate to a motor vehicle is by threaded fasteners passing through mounting holes of the license plate and then threading into aligned attachment holes of the motor vehicle, for example at the rear deck lid, lift gate, rear deck panel, or bumper.
[0003] License plate size is not universal around the world. There are, for example, different size license plates, with different mounting hole locations, used in each of North America, Europe, Japan, Korea, and the Persian Gulf States of the Middle East. Problematically, since automakers ship motor vehicles to a number of countries, the license plate attachment must be correctly chosen to fit the mounting holes of the license plate of the country of destination, and this requires an added cost involved in the customization. In this regard, it is presently customary to provide license plate attachment holes into the vehicle sheet metal specific to the country of destination of the vehicle, or alternatively, to not provide any license plate attachment holes at the manufacturing facility and default to the dealer the job of drilling the license plate attachment holes (which holes are problematic in that they result in exposed metal edges which are prone to rust initiation). Into each attachment hole a respective plastic (nylon) nut is secured, and a threaded fastener is placed respectively through each mounting hole of the license plate and then threaded into the nut. These customary license plate attachment hole options involve a cost impact, part number proliferation, sequencing, scheduling and warranty issues, as well as the need to install plastic appliques to hide unused attachment holes.
[0004] Accordingly, what is needed in the art is a license plate attachment system which can somehow universally accommodate different sized license plates used around the world.
SUMMARY OF THE INVENTION
[0005] The present invention is a universal attachment system for attaching to a motor vehicle the license plate from any of a number of countries, even though the locations of the attachment holes of the license plates may be different from country to country.
[0006] The universal attachment system according to the present invention includes a right nut body, a left nut body, and an attachment panel which carries the left and right nut bodies, and wherein the left and right nut bodies are provided with a plurality of preselected license plate attachment holes.
[0007] The left nut body includes a left main nut body component and a left satellite nut body component, wherein preferably a bridge connects the left main nut body component to the left satellite nut body component. Similarly, the right nut body includes a right main nut body component and a right satellite nut body component, wherein preferably a bridge also connects the right main nut body component to the right satellite nut body component. Each of the left and right main nut body components has at least one selected country license plate attachment hole (preferably four selected countries license plate attachment holes), and the left and right satellite nut body components each have provision for a European license plate attachment hole.
[0008] The attachment panel has first and second right openings and first and second left openings which are spaced horizontally with respect to the first and second right openings. In this regard, the left main nut body component is attached to the first left opening, the left satellite nut body component is attached to the second left opening, the right main nut body component is attached to the first right opening, and the right satellite nut body component is attached to the second right opening, wherein a plurality of pairs of license plate attachment holes are thereby provided at the attachment panel which are alignable with the mounting holes of various sized license plates.
[0009] In the preferred embodiment, each of the left and right main nut body components has a respective left and right entry boss having a complementary shape to that of the first left and right openings, a respective left and right main nut body head, and at least one guide slot formed, respectively, in each sidewall of the left and right entry bosses. Each of the left and right satellite nut body components has a respective satellite nut body head and a respective snap feature attached respectively thereto in depending, perpendicular relation.
[0010] In operation of the preferred embodiment, the right entry boss of the right main nut body component is placed through the first right opening such that the periphery of the first right opening is aligned with the at least one guide slot of the right main nut body component. The right nut body is then rotated so as to trap the periphery of the first right opening between the right entry boss and the right main nut body head. At this position, the snap feature of the right satellite nut body component is aligned over the second right opening, and the snap feature thereof is thereupon pressed snappingly into the second right opening. The left nut body is similarly mounted to the first and second left openings of the attachment panel. Finally, the mounting holes of the license plate of a particular country are aligned to an appropriate pair of license plate attachment holes of the left and right nut bodies, and thereupon a threaded fastener is threaded respectively into the aligned license plate attachment holes to thereby secure the license plate onto the attachment panel, which is, itself connected to the motor vehicle.
[0011] Accordingly, it is an object of the present invention to provide a license plate attachment system which accommodates attachment to a motor vehicle a number of license plates from various countries, wherein the license plates may have differing locations of the mounting holes formed therein.
[0012] This and additional objects, features and advantages of the present invention will become clearer from the following specification of a preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective view of a left nut body according to the present invention.
[0014] FIG. 2A is a top plan view of the left nut body of FIG. 1 .
[0015] FIG. 2B is a top plan view of a right nut body according to the present invention.
[0016] FIG. 3 is a side plan view of an attachment panel according to the present invention.
[0017] FIG. 4A is a bottom plan view of the left nut body of FIG. 1 .
[0018] FIG. 4B is a bottom plan view the right nut body of FIG. 2B .
[0019] FIG. 5 is an exploded, perspective, view of the left nut body of FIG. 1 .
[0020] FIG. 5A is a side view seen along line 5 A- 5 A of FIG. 5 .
[0021] FIG. 6 is a sectional view of the left nut body of FIG. 1 , seen along line 6 - 6 of FIG. 2A .
[0022] FIG. 7 is a side view showing the left and right nut bodies at a first stage of attachment to the attachment panel.
[0023] FIG. 8 is a side view as in FIG. 7 , now showing the left and right nut bodies at a second and final stage of attachment to the attachment panel.
[0024] FIG. 9A is a sectional view as in FIG. 6 of the left nut body, now shown at the final attachment stage with respect to the attachment panel.
[0025] FIG. 9B is sectional view, seen along line 9 B- 9 B of FIG. 9A .
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] Referring now to the Drawing, FIG. 8 depicts a license plate attachment system 10 according to the present invention. The license plate attachment system includes a left nut body 12 , a right nut body 14 and an attachment panel 16 to which the left and right nut bodies are attachable. The left and right nut bodies 12 , 14 have corresponding license plate attachment holes 26 which form pairs of mutually cooperating license plate attachment holes, each pair having predetermined mutual spacing between the holes to thereby provide alignment with the mounting holes of predetermined sizes of license plates.
[0027] Referring now to FIGS. 1 through 2 B, the left nut body 12 is shown, which is generally a mirror image of the right nut body 14 . The left and right nut bodies 12 , 14 have respective left and right main nut body components 20 L, 20 R, a respective left and right satellite nut body component 22 L, 22 R, and a respective bridge 24 L, 24 R connecting together each left and right main nut body component with its respective left and right satellite nut body component. Each of the left and right main nut body components 20 L, 20 R has at least one selected license plate attachment hole, forming, in combination, at least one cooperating pair of license plate attachment holes. It is preferred for four license plate attachment holes to be provided in each of the left and right main nut body components 20 L, 20 R, namely, a North American license plate attachment hole 26 A, a Japanese license plate attachment hole 26 B, a Korean license plate attachment hole 26 C, and a Persian Gulf States license plate attachment hole 26 D. As further shown by FIGS. 2A and 2B , each of the left and right satellite nut body components 22 L, 22 R has provision for a respective centrally disposed European license plate mounting hole 28 .
[0028] FIG. 3 shows the attachment panel 16 , which includes first and second left openings 32 L, 34 L and first and second right openings 32 R, 34 R. The left and right main nut body components 20 L, 20 R are structured to fastenably cooperate with the periphery 32 P of the first left and right openings 32 L, 32 R, and the left and right satellite nut body components 22 L, 22 R are structured to fastenably cooperate with the periphery 34 P of the second left and right openings 34 L, 34 R, as will be detailed hereinbelow. When the left and right nut bodies 12 , 14 are attached to the attachment panel, the relative positioning of the aforementioned license plate attachment holes are predetermined to provide pairs of license plate attachment holes, each of which being alignable with the mounting holes of a respective license plate, to wit: a pair of North American license plate attachment holes 26 A which are alignable with the mounting holes of a North American license plate, a pair of Japanese license plate attachment holes 26 B which are alignable with the mounting holes of a Japanese license plate, a pair of Korean license plate attachment holes 26 C which are alignable with the mounting holes of a Korean license plate, a pair of Persian Gulf States license plate attachment holes 26 D which are alignable with the mounting holes of a Persian Gulf States license plate, and a pair of European license plate attachment holes which are alignable with the mounting holes of a European license plate.
[0029] Each of the left and right main nut body components 20 L, 20 R has a respective left and right main nut body head 38 L, 38 R. As shown at FIGS. 4A through 6 , it is preferred for the license plate attachment holes 26 A- 26 D to be in the form of blind bores 26 ′ defined by closed-end cylindrical casings 26 ″ which are integrally formed with a rear side 38 A of each of the left and right main nut body heads 38 L, 38 R in perpendicular relation thereto such that the blind bores open at a front side 38 B of the left and right main nut body heads. In this regard, a threaded fastener may be threaded into a blind bore 26 ′, and if later backed out, the blind bore remains intact, without breakage. This feature is particularly useful should a user accidentally drive a threaded fastener into a “wrong” license plate attachment hole 26 A- 26 D, in that environmental integrity is maintained. The blind bores 26 ′ preferably have four axially disposed flutes for facilitating threading thereinto by a threaded fastener.
[0030] Each of the left and right satellite nut body components 22 L, 22 R has a respective left and right satellite nut body head 40 L, 40 R and a respective pair of legs 42 perpendicularly projecting from a rear side 40 A of each of the respective left and right satellite nut body heads, wherein a semi-cylindrical cut-out is formed in each leg of the pairs of legs in bilateral disposition to form a threaded fastener receptacle 46 . At the front side 40 B of the satellite nut body heads 40 L, 40 R, a piercible recess surface 44 is formed which demarcates an entry location for a threaded fastener. The recess surface 44 is aligned with the threaded fastener receptacle 46 , such that piercing of the recess surface results in a threaded fastener passing therethrough and threadably engaging the threaded fastenerreceptacle.
[0031] Each pair of legs 42 has a snap feature 48 in the form of radially oriented V-shaped surfaces disposed opposite the threaded fastener receptacle 46 . A grommet 50 is provided with each of the left and right satellite nut bodies 22 L, 22 R as a separate, snap-on piece. Each grommet 50 has a down-turned peripheral grommet lip 52 and a central aperture 54 , wherein each grommet is snap fit onto a respective pair of legs 42 via interaction of its snap feature 48 with the periphery of the central aperture.
[0032] As shown best at FIGS. 4A through 5 , an entry boss 60 L, 60 R is attached, respectively, to each of the rear side 38 A of the main nut body heads 38 L, 38 R, preferably by sonic welding. In this regard, the rear side 38 A of each of the left and right main nut body heads 38 L, 38 R is provided with alignment pins 62 which are received into cooperating alignment holes 64 of its respective entry boss 60 L, 60 R. Additionally, each of the left and right entry bosses 60 L, 60 R is provided with cylindrical casing holes 66 for receiving therethrough the cylindrical casings 26 ″ of its respective left and right main nut body head 38 L, 38 R.
[0033] As indicated at FIGS. 4A, 4B and 5 A, the sidewall 68 of each of the left and right entry bosses 60 L, 60 R is provided with at least one guide slot 70 (four guide slots being shown, one guide slot at each side of the sidewall) running from a midpoint M and passing through a respective corner C thereof. As shown at FIG. 5A , each guide slot 70 is tapered, having its least height H at the corner C and maximum height at the midpoint M, the purpose of which will become clear momentarily. FIGS. 4A and 4B show that each guide slot cuts into the sidewall 68 with a shallow diagonal, having least depth at the midpoint and maximum depth at the corner.
[0034] The rear side 38 A of each of the left and right main nut body heads 38 L, 38 R has a down turned peripheral main head lip 72 . As can be understood best from FIGS. 4A and 4B , the orientation of the entry bosses 60 L, 60 R is skewed relative to the periphery of their respective left and right main nut body heads 38 L, 38 R, as for example a skew angle S of 20 . 15 degrees (see FIG. 4B ). This skewing is predetermined so as to provide proper operation with respect to the first and second left and right openings 32 R, 32 L, 34 R, 34 L, respectively, as will become clear momentarily.
[0035] Referring again to FIG. 3 , the second left and right openings 34 L, 34 R are located on the attachment panel 16 such that the distance between the respective centers thereof is equal to the distance between the center of each of the mounting holes of a European license plate. Accordingly, by placing the satellite nut body components 22 L, 22 R respectively at the second left and right openings 34 L, 34 R, the European attachment holes 28 (each composed of the threaded fastener receptacle 46 thereof and piercing of the recess surface 44 thereat) are aligned with the license plate mounting holes of a European license plate. In this regard, the snap feature 48 of each of the satellite nut body components snappingly engages the periphery of its respective second left and right opening 22 L, 22 R when pushed thereinto.
[0036] Now, with the satellite nut body components 22 L, 22 R located at the respective second left and right openings 22 L, 22 R, the respective bridges 24 L, 24 R orient the main nut body components 20 L, 20 R such that their respective license plate attachment holes 26 A- 26 D form pairs of license plate attachment holes, each pair having holes being spaced so as to be alignable with the mounting holes of a license plate of a particular country. That is, the North American license plate attachment holes 26 A form a pair of North American license plate attachment holes which are spaced for alignment with the mounting holes of a North American license plate, the Japanese license plate attachment holes 26 B form a pair of Japanese license plate attachment holes which are spaced for alignment with the mounting holes of a Japanese license plate, the Korean license plate attachment holes 26 C form a pair of Korean license plate attachment holes which are spaced for alignment with the mounting holes of a Korean license plate, and the Persian Gulf States license plate mounting holes 26 D form a pair of Persian Gulf attachment holes which are spaced for alignment with the mounting holes of a Persian Gulf States license plate.
[0037] It is preferred for the left and right nut bodies 12 , 14 , including the entry bosses 60 L, 60 R and the grommets 44 be composed of a nylon material, however, other corrosion resistant, durable materials may be used.
[0038] Tool-free installation of the left and right nut bodies 12 , 14 with respect to the attachment panel 16 will now be described with reference to FIGS. 7 through 9 B.
[0039] Firstly, each entry boss 60 L, 60 R is placed into its respective first left and right opening 32 L, 32 R. In this regard, the entry bosses 60 L, 60 R and the first left and right openings 32 L, 32 R are of complementing rectangular shapes which define a respectively exclusive entry orientation of the left and right nut bodies 12 , 14 whereby the respective satellite nut body components 22 L, 22 R are located generally adjacent their respective second left and right openings 34 L, 34 R, as defined by the aformentioned skew angle. In the position shown at FIG. 7 , the main head lip 72 abuts the attachment panel 16 and the at least one guide slots 70 are aligned with the periphery of the first left and right openings 32 L, 32 R.
[0040] Next, the left and right nut bodies 12 , 14 are rotated along respective arrows A, A′, such that the satellite nut body components 22 L, 22 R are aligned over their respective second left and right openings 34 L, 34 R of the attachment panel 16 (see FIG. 8 ), again as defined by the skew angle. In performing the rotation, the periphery of the first left and right openings 32 L, 32 R is increasingly tightly trapped in the at least one guide slots 70 as the height of the at least one guide slots decreases with respect to the respective left and right main body washer head 38 L, 38 R (see FIG. 9A ). Now the satellite nut body components 22 L, 22 R are pressed toward the attachment panel 16 , thereby forcing the snap feature 48 into the respective second left and right openings 34 L, 34 R (see FIG. 9B ). Upon completion of installation, the grommet and main head lips 52 , 72 are in firmly abutting relation with the attachment panel so as to thereby provide a sealing relationship therebetween.
[0041] FIGS. 10A through 20E depict the license plate attachment system 10 in operation with respect to license plates of various countries.
[0042] In FIG. 10A , a North American license plate 80 has mounting holes 80 A which are aligned with the North American attachment holes 26 A, and a threaded fastener 90 has been respectively passed through each of the mounting holes 80 A and threaded into each of the North American license plate attachment holes 26 A so as to thereby attach the North American license plate to the attachment panel 16 , and, consequently, the motor vehicle.
[0043] In FIG. 10B , a Japanese license plate 82 has mounting holes 82 A which are aligned with the Japanese attachment holes 26 B, and a threaded fastener 90 has been passed respectively through each of the mounting holes 82 A and threaded into each of the Japanese license plate attachment holes 26 B so as to thereby attach the Japanese license plate to the attachment panel 16 , and, consequently, the motor vehicle.
[0044] In FIG. 10C , a Korean license plate 84 has mounting holes 84 A which are aligned with the Korean attachment holes 26 C, and a threaded fastener 90 has been respectively passed through each of the mounting holes 84 A and threaded into each of the Korean license plate attachment holes 26 C so as to thereby attach the Korean license plate to the attachment panel 16 , and, consequently, the motor vehicle.
[0045] In FIG. 10D , a Persian Gulf States license plate 86 has mounting holes 86 A which are aligned with the Persian Gulf States attachment holes 26 D, and a threaded fastener 90 has been respectively passed through each of the mounting holes 86 A and threaded into each of the Persian Gulf States license plate attachment holes 26 D so as to thereby attach the Persian Gulf States license plate to the attachment panel 16 , and, consequently, the motor vehicle.
[0046] In FIG. 10E , a European license plate 88 has mounting holes 88 A which are aligned with the European attachment holes 28 , and a threaded fastener 90 has been respectively passed through each of the mounting holes 88 A, pierced each of the recesses 44 and threaded into each of the European license plate attachment holes 28 so as to thereby attach the European license plate to the attachment panel 16 , and, consequently, the motor vehicle.
[0047] To those skilled in the art to which this invention appertains, the above described preferred embodiment may be subject to change or modification. For example, the bridges could be omitted. Such change or modification can be carried out without departing from the scope of the invention, which is intended to be limited only by the scope of the appended claims. | A universal attachment system for attaching to a motor vehicle the license plate from a number of countries, even though the locations of the attachment holes of the license plates may be different from country to country. A right nut body has a first plurality of license plate attachment holes, a left nut body has a second plurality of license plate attachment holes, and an attachment panel which carries the left and right nut bodies. The first and second pluralities of license plate attachment holes provides a plurality of pairs of license plate attachment holes for aligning with the license plate mounting holes of any, or all, of a North American, Japanese, Korean, Persian Gulf States and European license plate | 1 |
PRIORITY CLAIM
The present application claims the priority benefit of U.S. provisional patent application No. 62/121,010 filed Feb. 26, 2015 and entitled “Vertically Aligned Metal Nanowire Arrays and Composites for Thermal Management Applications,” the disclosure of which is incorporated herein by reference.
CROSS-REFERENCE TO RELATED APPLICATION
This application contains subject matter that is related to the subject matter of the following applications, which are assigned to the same assignee as this application. The below-listed U.S. Patent application is hereby incorporated herein by reference in its entirety:
“THERMAL INTERFACE MATERIALS USING METAL NANOWIRE ARRAYS AND SACRIFICIAL TEMPLATES,” by Barako, Starkovich, Silverman, Tice, Goodson, Coyan, and Peng, filed on Jan. 26, 2016, U.S. Ser. No. 15/006,597.
SUMMARY
A thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface includes the steps of: removing a template membrane from the MNW; infiltrating the MNW with a bonding material; placing the bonding material on the adjacent surface; bringing an adjacent surface into contact with a top surface of the MNW while the bonding material is bondable; and allowing the bonding material to form a solid bond between the MNW and the adjacent surface.
A thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface includes the steps of: choosing a bonding material based on a desired bonding process; and without removing the MNW from a template membrane to which the MNW is connected, depositing the bonding material onto a tips of the MNWs.
A metal nanowire (MNW) array includes: a vertically-aligned metal nanowire (MNW) array comprising a plurality of nanowires that grow upward from a seed layer deposited onto a template membrane, the template membrane being removed after MNW growth.
A metal nanowire (MNW) array includes a metal nanowire (MNW) array attached at the MNW tips to an adjacent surface by mushroom-like caps of thermally-conductive and mechanically-robust bonding material.
A metal nanowire (MNW) array includes a metal nanowire (MNW) array attached at the MNW tips to a continuous overplating layer of bonding material covers the template membrane.
DESCRIPTION OF THE DRAWINGS
The accompanying drawings provide visual representations which will be used to more fully describe various representative embodiments and can be used by those skilled in the art to better understand the representative embodiments disclosed herein and their inherent advantages. In these drawings, like reference numerals identify corresponding elements.
FIGS. 1A-1C is a set of three drawings showing a thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface.
FIG. 2 is a drawing showing a thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface.
FIG. 3 is a flowchart of a thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface.
FIG. 4 is a flowchart of a thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface.
DETAILED DESCRIPTION
While the present invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail one or more specific embodiments, with the understanding that the present disclosure is to be considered as exemplary of the principles of the invention and not intended to limit the invention to the specific embodiments shown and described.
A thermally-conductive and mechanically-robust bonding procedure is provided to attach a metal nanowire (MNW) array to two adjacent surfaces.
A thin metallic bonding layer can be used to anchor the individual MNWs to the adjacent surface without compromising the mechanical properties of the MNW. For example, a thickness of the metallic bonding layer is less than approximately 20% of one or more of the length of the MNW array and the height of the MNW array.
According to embodiments of the invention, metallically-bonded MNW MNWs may be implemented by infiltrating an interstitial volume of the MNW array with a bonding material and using adhesion of the bonding material to the adjacent surfaces as a method of attachment.
Alternatively, the tip of each MNW can be metallically bonded to an adjacent surface using a process that in parallel bonds all of the MNWs in the array. For example, while the MNWs are still in the membrane, a post MNW growth electrodeposition step can be used to deposit mushroom-like caps of bonding metal or alloy material onto the tips of the MNWs. The bonding cap can comprise one or more of a fusible metal and an alloy similar to a solder, a brazing agent or a diffusion bonding metal. An additional bonding layer is added at the top of the MNW.
If the MNWs are not grown to substantially extend to the full thickness of the membrane, then a bonding material can be deposited at the tip of the MNW to form a compound, segmented MNW. The segmented MNW is principally comprised of the conductive material while only a short section, less than 20% of the total MNW length located at the tip of the MNW is composed of the bonding material. If a slightly thicker bonding layer is desired, the electrodeposition of the bonding material can be continued until a continuous overplating layer of bonding material substantially covers the surface of one or more of the membrane and the MNW array. For example, the conductive material comprises one or more of copper and silver.
The bonding material is chosen based on the desired bonding process used. For example, one or more of a eutectic metal and a solder can be used for phase change bonding, where heating is applied to melt and adhere the molten bonding layer to the adjacent surface. Alternatively, the bonding material can be one or more of tin and gold and can be bonded using thermocompressive bonding. Alternatively, the bonding material comprises a polymer material. Other types of metallic bonding include brazing and welding, which can also be used to attach a bonding material at the MNW tips to an adjacent material.
FIGS. 1A-1C is a set of three drawings showing a thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface. The legend indicates the various components.
In FIG. 1A , following deposition and growth of the MNWs, the template membrane used in generating the MNWs is removed.
In FIG. 1B , the MNW array is then infiltrated with one or more of a fusible metal, an alloy, and a polymer resin, creating bondable material. For example, the bondable material comprises molten material. For example, the bondable material is wicked by capillary forces into an interstitial volume of the MNW array by capillary forces. Bonding material is then placed on an adjacent surface to the MNW.
In FIG. 1C , an adjacent surface is brought into contact with a top surface of the MNW while the bonding material is bondable. For example, the bondable material comprises molten material. The bonding material is allowed to form a solid bond between the MNW and the adjacent surface. This process compresses one or more of the bonding material and the MNW array against the adjacent surface.
An additional step (not pictured) may be performed of wetting the bonding material to the adjacent surface.
FIG. 2 is a drawing showing a thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface. The tips of an MNW array are bonded to an adjacent surface.
In step 210 , an MNW array is synthesized. The MNW array is grown to be either subfilled, where the length of the MNWs is less than the membrane thickness, as shown in step 215 , or filled to the top of the membrane such that the tips of the MNWs are even with the top surface of the membrane, as shown in step 220 . In either case, the membrane is left in place around the MNWs.
In step 225 , a bonding layer is deposited onto the tips of the MNWs. This bonding layer can take one of three different forms. As shown in step 230 , if the MNW array is subfilled, a small amount of bonding material can be deposited directly onto the tip of each individual MNW, forming a short MNW segment of bonding material.
As shown in step 235 , if the MNW array is filled to the membrane thickness, a small amount of bonding material can be deposited onto the tip of each individual MNW, forming a small mushroom-cap of bonding material above each individual MNW.
As shown in step 240 , if the MNW array is filled to the membrane thickness, a large amount of bonding material can be deposited onto the surface of the array and membrane to form a continuous film of bonding material.
In step 250 , the MNWs are bonded and the template membrane is removed.
In step 255 , the template membrane is removed from the previously subfilled MNW array, and then in step 260 , the MNW array is bonded to the adjacent substrate.
In step 265 , for the embodiments with bonding layer caps or with bonding layer overplating, the MNW array is first bonded to the adjacent substrate. The most common types of metallic bonding are solder/eutectic bonding, where the bonding material comprises one or more of a solder and a eutectic and where bonding is performed under heating and optional compression, and thermocompressive bonding, where the bonding material comprises one or more of tin and gold, and wherein bonding is performed under heating and compression.
In step 270 , the template membrane is removed from the MNW array. FIG. 3 is a flowchart of a thermally-conductive and mechanically-robust bonding method 300 for attaching a metal nanowire (MNW) array to an adjacent surface.
In step 310 , a template membrane is removed from the metal nanowire (MNW) array. Block 310 then transfers control to block 320 .
In step 320 a bonding material is placed on an adjacent surface to the MNW. Block 320 then transfers control to block 330 .
In step 330 the MNW is infiltrated with a bonding material. For example, the step of infiltrating comprises heating the bonding material so that it becomes one or more of softened and molten. For example, the step of infiltrating comprises chemically treating a composite material so as to create a bonding material. Block 330 then transfers control to block 340 .
In step 340 , a surface adjacent to the MNW is brought into contact with a top surface of the MNW while the bonding material is bondable. Block 340 then transfers control to block 350 .
In block 350 , the bonding material is allowed to form a solid bond between the MNW and the adjacent surface. Block 350 then terminates the process.
FIG. 4 is a flowchart of a thermally-conductive and mechanically-robust bonding method 400 for attaching a metal nanowire (MNW) array to an adjacent surface.
In step 410 , a bonding material is chosen based on a desired bonding process. Block 410 then transfers control to block 420 .
In step 420 , without removing a metal nanowire (MNW) array from a template membrane, the bonding material is deposited onto a tip of the MNW. Block 420 then terminates the process.
Advantages of the invention include high thermal conductivity outside of the interfaces and formation of a cohesive joint between the two components. Embodiments of the invention minimize the thermal resistance between the MNW surface and the adjacent surface and provide long-lifetime adhesion that preserves its integrity under temperature gradients and thermal cycling. Fusible metal MNWs are used in applications where the mechanical stresses are comparatively low or for applications where the minimization of device temperature rise (or equivalently for high-heat flux devices) is the priority of the thermal design. For example, the mechanical stresses are less than approximately 20 megapascals (20 MPa).
Fusible metals undergo a phase change during bonding and can provide direct adhesion to adjacent surfaces. However, the resulting MNW must be comparatively thick since the bonding metal is stiff and mismatch in the coefficients of thermal expansion can cause the interface to fail. In vertically-aligned MNWs, the MNWs provide both high thermal conductivity (greater than 20 watts per meter-kelvin [W/m-K]) and mechanical compliance. For example, the mechanical compliance is between approximately 10 megapascals (MPa) and approximately 100 MPa. For example, the mechanical compliance is between approximately 10 MPa and 1,000 MPa. The MNWs themselves provide the mechanical flexibility. The bond serves primarily to transfer heat between the surface and the MNW array and to maintain mechanical integrity of the interface.
While the above representative embodiments have been described with certain components in exemplary configurations, it will be understood by one of ordinary skill in the art that other representative embodiments can be implemented using different configurations and/or different components. For example, it will be understood by one of ordinary skill in the art that the time horizon can be adapted in numerous ways while remaining within the invention.
The representative embodiments and disclosed subject matter, which have been described in detail herein, have been presented by way of example and illustration and not by way of limitation. It will be understood by those skilled in the art that various changes may be made in the form and details of the described embodiments resulting in equivalent embodiments that remain within the scope of the invention. It is intended, therefore, that the subject matter in the above description shall be interpreted as illustrative and shall not be interpreted in a limiting sense. | A thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface includes the steps of: removing a template membrane from the MNW; infiltrating the MNW with a bonding material; placing the bonding material on the adjacent surface; bringing an adjacent surface into contact with a top surface of the MNW while the bonding material is bondable; and allowing the bonding material to cool and form a solid bond between the MNW and the adjacent surface. A thermally-conductive and mechanically-robust bonding method for attaching a metal nanowire (MNW) array to an adjacent surface includes the steps of: choosing a bonding material based on a desired bonding process; and without removing the MNW from a template membrane that fills an interstitial volume of the MNW, depositing the bonding material onto a tip of the MNW. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method for precipitating or flocculating substances out of solutions.
2. Discussion of the Relevant Art
Undesirable ionic substances contained in water can be removed when they are transformed into the form of a sparingly soluble salt or mineral and are thus precipitated. Many metal ions, such as, for example, Ca 2+ , Mg 2+ , Fe 2+ , Me 2+ ions can be precipitated in the form of sparingly soluble hydroxides. Such reactions can be controlled via the pH value.
Ca 2+ ions in water are removed on a commercial scale in that they are precipitated as CaCO 3 (calcium carbonate) (decarbonization) This reaction is also controlled via the pH value.
Closely related to the precipitation of substances contained in water is the term of flocculation and sedimentation. This is so because the removal of (precipitated) substances contained in water requires:that they can also be separated from the water. In the context of flocculation and sedimentation it is important how the precipitated products grow further and/or can conglomerate. The addition of certain salts (aluminum salts, iron salt) can control this behavior.
In the conventional method technology it is difficult to avoid a local overdosage when introducing the flocculation agent (for example, when adding sodium hydroxide solution or when dissolving sodium hydroxide pellets). A local overdosage can result in the precipitation of inherently less soluble substances contained in the water which then cause, as an entrained solid particle, component hard-to-control conditions in the subsequent precipitation process.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved method for precipitation or flocculation of substances contained in solutions, especially water.
According to the invention, the method is characterized in that the solution is brought into contact with at least one ion exchange material which releases ions into the solution that effect precipitation or flocculation and/or has on its surface functional groups which catalytically effect flocculation or precipitation.
Ion exchange materials have been used in water or sewage treatment in order to exchange undesirable ions against desirable ions or ions that are less disruptive for the respective application purposes. Known are, for example, water softening devices which by means of ion exchangers bind Ca 2+ and/or Mg 2+ in exchange for Na 2+ or H + ions. Anionic exchangers (mostly in the Cl − or OH − form) allow the removal of undesirable anions (NO 3− , HCO 3− etc.) from the water. Known are also methods in which the Cu 2+ ion or heavy-metal ions are removed by means of ion exchangers from the water. All these methods have in common that the ions removed from the water are bonded to the resin; once the capacity of the resin is depleted, it must be regenerated. During the regeneration process, the metal ions which have been concentrated can be, for example, removed from the regenerated compound.
Novel is now the idea to employ an ion exchange material for inducing a precipitation or flocculation process.
According to a first aspect of the invention, ion exchange materials are used as supports for the ions which in solution make the precipitation reaction possible. The component required for transformation of the ionic species to be precipitated into a sparingly soluble salt/mineral is provided by the ion exchange material which has been conditioned for this purpose. For example, an ion exchange resin of the OH − form provides the required OH − ions for a hydroxide precipitation in order to, for example, precipitate Fe 2+ and Mn 2+ in the form of hydroxides but of the water. Ag + ions in the water can be precipitated as AgCl in the presence of an anionic exchange resin of the Cl − form.
When using specially conditioned ion exchange materials, the following advantages will result relative to the prior art in the field of water treatment:
The ion exchange material allows the directed addition of the components required alone for the precipitation reaction, for example, for the decarbonization of calcium carbonate-containing water. The principle of decarbonization of calcium carbonate-containing water is that the pH value is to be raised in order to shift the calcium carbonate/carbonic acid equilibrium such that the Ca 2+ ions will precipitate in the form of calcium carbonate. Conventionally, the pH value increase is achieved by adding Ca(OH) 2 NaOH and/or NaCO 3 . This addition has the disadvantage that with the OH − or CO 3 2− ions acting as a base, additionally Ca 2+ or Na 30 ions are introduced into the water which partially counteract (additional Ca 2 + ions which must be precipitated) or limit (sodium limit value in drinking water) the success of the method.
A weakly basic ion exchange resin of the OH − form only releases OH − ions; an ion exchange resin of the HCO 3− /CO 3 2− releases only CO 3 2− and HCO 3− ions.
Better control of the precipitation process by avoiding local overdosage, especially in combination with a fluidized bed variant.
The possibility of controlling the precipitation process by means of the contact time of the water to be treated with the ion exchange material.
The ion exchange is a surface process and depends on the degree of loading of the ion exchange material with the ions required for the reaction and the type and concentration of ions in the solution which can be exchanged for the ions on the resin.
The contact time can be adjusted simply and can be changed optionally (by the size of the ion exchange resin bed and the flow-through amount in continuous operation; via the residence time in the reaction vessel (tank) during batch operation).
The recyclability of the ion exchange material.
Depleted ion exchange material, especially resins, can be removed easily from the reaction vessel or tank and regenerated. The regenerated material can then be returned into the process.
Ion exchange materials can be used as carriers of ions which control the flocculation in solution. In analogy to the above described mechanism, ions which enhance the flocculation of substances contained in the water (for example, Al 3+ and Fe 3+ ions) can also be brought into the corresponding solution by ion exchange from an ion exchange material (it is then required to provide an ion exchange material that is at least partially loaded with Al 3+ and Fe 3+ ions). All advantages are also applicable here.
For certain processes, the combination of dosage of pH-controlling ions (for example, anionic exchangers of the OH − form) and flocculation agents (for example, cationic exchangers in the Fe 2+ form) is expedient.
According to a second aspect of the invention, a specially conditioned ion exchange material can be used as a catalyst for precipitation of substances contained in water. In many real solutions there is the situation that the solution, when considered thermodynamically, is oversaturated with respect to a dissolved phase. Despite this fact, within a finite time period no precipitation takes place which would bring the solution into equilibrium. Such meta-stable solutions lack suitable growth locations where the precipitation could take place. Suitable growth locations are crystal seeds of the phase to be precipitated or special heterogeneous surfaces which decrease considerably the seed formation work and thus make the formation of crystal seeds in the range of low saturations possible. An example for such a solution is water which is oversaturated with respect to calcium carbonate.
It is known that biological systems (muscles, algae etc.) are able to initiate a directed crystal seed formation by means of certain functional groups. In particular, it was found that the carboxyl group of certain carboxylic acids (stearic acid etc.) induces calcium carbonate crystal seed formation. In regard to a mechanism of this reaction, it is assumed that carboxyl groups first bind Ca 2+ ions from the water and that only this combination is able to induce the calcium carbonate crystal seed formation.
Ion exchange materials obtain their specific properties also as a result of certain functional groups: strongly acidic ion exchange materials carry as active functional groups, for example, the sulfonate group; weakly acidic ion exchangers have as active functional groups, for example, the carboxyl group (COO − ).
When the carboxyl group of a weakly acidic ion exchange material is loaded by means of a loading process preferably completely with Ca 2+ ions, this loaded material is suitable to catalytically form CaCO 3 crystal seeds on its surface in aqueous calcium carbonate-containing solutions.
Such a conditioned weakly acidic ion exchange material can be used, for example, as a nucleus-forming agent and filter pellet in conventional decarbonization devices; and, furthermore, for the increase of the seed formation rate and thus the efficiency in the method and device described in the German patent application DE 19606633 A1. The contents of DE 19606633 A1 is included in the disclosure of the present application.
The catalytic efficiency depends on the bonding strength (electrostatic association) between carboxyl group and the Ca 2+ ion: a bond which is too strong would not make possible the association of carbonate ions from the solution required for the seed formation; a bonding that is too loose would result in the loss of Ca 2+ and thus in the destruction of the catalytic complexes. The electrostatic association of carboxyl groups and Ca 2+ ions on the interface ion exchange material/water is affected by the electrical field on the interface. The catalytic efficiency of these specially loaded ion exchange materials is accordingly increased when they are, for example, applied to the electrodes described in the international application WO 95/26931 or produces them therefrom and, in this way, modulates or adjusts the functional groups by means of the described intrinsic electrical field. The contents of WO 95/26 931 thus is included in the disclosure of the present application.
EMBODIMENTS
The decarbonization of calcium carbonate-containing water via the directed dosage of OH − ions via an ion exchange resin:
On a commercial scale, the decarbonization of calcium carbonate-containing water has been realized in that, by addition of certain chemicals (milk of lime, sodium hydroxide, soda), the pH value of the water was raised and thus the calcium carbonate/carbonic acid equilibrium was shifted greatly toward oversaturation. The resulting homogenous seed formation generated calcium carbonate crystal seeds on which the calcium carbonate dissolved in water then would precipitate (Mg 2+ ions precipitate as Mg(OH) 2 ).
The success of the method depends greatly on the type of process control.
The use of sodium hydroxide for increasing the pH value is a problem because at the location of addition of the sodium hydroxide an extreme pH value increase results locally which causes the precipitation of undesirable hydroxides. These hydroxides, for example, Ca(OH) 2 colloids, are entrained as solid bodies into the process water and make the required pH value adjustment after the decarbonization process more difficult.
The problem when using milk of lime (Ca(OH) 2 ) lies in the preparation of the solution to be added and the addition: it is practically impossible to produce a dosage solution which is free of Ca(OH) 2 colloids. When these colloids are not completely dissolved in the decarbonization step, they present a great problem in the pH value reduction required subsequently.
The addition of milk of lime also adds further Ca 2+ ions to the water which in the subsequently precipitation process are only partially precipitated also. Often, additional carbonate (in the form of soda-Na 2 CO 3 ) must be added in order to be able to satisfactorily remove Ca 2+ ions by precipitation. However, this also results in the undesirable increase of the Na + contents in the water.
The goal of an optimal process control is furthermore a controlled seed formation rate: too many crystal seeds compete in regard to their growth and grow only to small calcium carbonate crystals which can be separated only with difficulty from the process water (sedimentation speed is too low, filtration is complex).
The use of a (strongly basic) anionic exchanger (for example, of the OH − form) makes it possible to have an optimal process control.
BRIEF DESCRIPTION OF THE DRAWINGS
In FIG. 1 a schematic of a decarbonization device that operates on the basis of strongly basic anionic exchangers is illustrated.
FIG. 2 shows a device for producing seed crystals.
FIGS. 3 and 4 show further embodiments of a device suitable for performing the method according to the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
In the decarbonization stage 1 of FIG. 1 the raw water flows via the line 2 first through a bed of strongly basic ion exchange material 3 ; by means of ion exchange the pH value of the water is adjusted to a pH value between 9 and 10 (depending on decarbonization efficiency). The control of the pH value. is carried out by means of the average contact time of the raw water with the ion exchange material 3 (flow-through, resin amount). By raising the pH value, a homogeneous seed formation results, and, accordingly, calcium carbonate precipitation is caused. The precipitated calcium carbonate is separated in the following filter stage 4 according to the prior art by sedimentation and/or filtration from the process water (sedimentation filter 6 ). In the third stage 5 the pH value is optionally adjusted.
In order to make possible the continuous operation of such a device, it is expedient to regenerate the ion exchange material continuously. This is carried out best in that a part of the partially spent material 3 is removed from the bed, for example, by a vacuum and supply line 7 . The removed amount is replaced by a corresponding amount of freshly regenerated ion exchange material 3 , is regenerated (regeneration is carried out in the regeneration device 8 , for example, with acids or electrolytically, wherein at the same time disinfection and washing can occur) and is then available for further use.
Expediently, the device (stage 1 ) is operated by fluidized bed operation. With the ion exchange material supply and removal device, used ion exchange material is removed periodically or continuously from the fluidized bed and replaced by fresh resin. Cleaning is possible by means of backwash lines 9 and the flushing outlets 10 .
In order to raise for hard water with a total hardness of 4 mmol/l, a DIC contents of also 4 mmol/l, and a pH value of 8.0, the pH value to approximately 9.5, approximately 1 mmol/l base or OH − ions are required. A strongly basic ion exchanger of the OH − form, for example, Lewait MP 600 of the firm Bayer/5/, has a capacity of typically 1 val/l, i.e., based on the requirement of 1 mmol/l OH − ions per liter raw water, approximately 1000 liters can be correspondingly treated per liter resin.
The resin amount required for a certain treatment efficiency depends on the contact time resin/water required for the pH value increase. In the above described water, a contact time of approximately 30 seconds is sufficient for a pH value increase to 9.5. For a decarbonization device with an output of 100 m 3 /h this results in a required resin amount of approximately 850 liters.
Iron Removal, Demagnetization of Water
In a similar manner the reduction of iron and manganese ions from the water can be carried out. For this purpose, preferably a weakly basic anionic exchanger material, for example, Lewait MP62 of the firm Bayer, is used because, generally, only a medium pH value increase is required in order to initiate the precipitation of iron and manganese hydroxides.
In order to improve flocculation of the hydroxides, it is beneficial to add in minimal amounts to the resin bed a resin which is loaded with aluminum ions or complexes (for example, a strongly acidic ion exchange resin Lewait S 100 of the firm Bayer loaded with aluminum ions).
Catalytic Precipitation of Calcium Carbonate
A weakly acidic ion exchange material preferably completely loaded with Ca 2+ ions, for example, a resin Lewait CNP 80 of the firm Bayer, triggers in calcium carbonate-containing solutions catalytically calcium carbonate crystal seed formation.
The latter resin can be used, for example, in order to enhance or to replace the above described decarbonization. In the process control of decarbonization it is favorable not to allow the pH value to become too high in order to maintain a crystal seed concentration that is not too great. A pH value that is too great increases also the expenditure of the subsequent pH value reduction. A crystal seed density that is too high results in many small calcium carbonate crystals which can be separated only with difficulty from the water. A weakly acidic resin of the Ca 2+ form forms crystal seeds also for low oversaturation. With the use of this resin it is possible to control the process such that the pH values must not be controlled above the pH value 9 so that the oversaturation remains in a range in which no sudden high crystal seed density is generated.
The converted CNP 80 can be dried, ground, and applied as a thin layer onto a support, for example, the electrodes disclosed in the international application WO 95/26931. With the intrinsic field of such a coated electrode, the catalytic activity of the functional groups can be controlled. In this manner, the directed crystal seed formation can be initiated. This effect can be used in water treatment in order to supply a defined amount of calcium carbonate crystal seeds to the process water.
In this context, the invention is in no way limited to known ion exchange materials. It is only important that the employed material can carry active groups which are able to receive ions from the solution and to release others instead. These groups therefore must have a finite dissociation constant in the liquid in question.
In order for the materials to have catalytic properties, it is additionally advantageous when those materials are used which have a microstructure favorable for the crystallization. This is, for example, the case when the basic matrix onto which the groups are applied, is a two-dimensional template which has a good conformity with the lattice constant of the crystal to be formed so that electrostatic and stereochemical conditions as in the crystal to be formed are present. The active groups are then to be prepared such that at least an ionic component of the substance to be crystallized is absorbed. It is then able in the oversaturated solution to initiate crystal seed formation on the interface.
In this respect, suitable materials (matrix or support materials) are preferably polyacrylate, polystyrene, activated carbon (as granules or porous semi-finished parts in the form of disks, cylinders, hollow cylinders) which can be functionalized preferably with a carboxyl group. The carboxyl group is usually saturated during the manufacturing process in the H + form. In order to use this material, for example, for the catalytic crystallization of calcium carbonate, the H + ions are replaced by cations of sparingly soluble salts (for example, Ca 2 , Mg 2+ , Fe 2+ , Cu 2+ etc.) so that in the end an ion exchange material in the respective cationic form is present (Ca 2+ form, Mg 2+ form, Fe 2+ form, Cu 2+ form etc.). The geometric position of the Ca 2+ ions on the surface of a polyacrylate resin ball of the weakly acidic ion exchange resin Lewatit CNP80 of the firm Bayer is determined by the molecular geometry of the polyacrylate matrix. The thus produced surface now exhibits good electrostatic and stereochemical properties for the formation of CaCO 3 crystals.
As already mentioned above, the electrostatic and stereochemical properties are important for the catalytically induced formation of crystal seeds on the respective surface. The stereochemical and substantially also electrical properties are adjusted via the structure of the basic material (for example, polyacrylate) on which the active groups are seated.
The electrostatic properties can be affected additionally by an external electrostatic field. In a simple way, this can be realized by introducing the catalyst material between two field-generating electrodes. As a concrete realization for this purpose, the container wall (for example, of a fluidized bed reactor) can be switched as a cathode and an anode can be positioned centrally within the tank.
However, an especially elegant variant results when the catalyst material is applied as a thin layer on an electrode, as is described, for example, in the international application WO 95/26931, and the electrostatic properties of the catalytic boundaries are adjusted by means of an intrinsic field.
FURTHER APPLICATION EXAMPLES
Example 1
Such a catalyst can be used for the formation of seed crystals which are distributed by the water flow in the installation and pipeline system downstream. Accordingly, seed crystals thus are formed as the precipitation product. It is known that such crystal seeds can prevent by their growth process the deposition on pipe walls or heat registers of hot water heaters. For the protection of a drinking water installation in a household, it is, for example, possible to use a fluidized bed reactor 11 (volume approximately 6 to 8 liters, diameter 15 cm, height 60 cm) with a catalyst filling (for example, four liters). The catalyst bed 12 is, for example, formed by a weakly acidic cationic exchanger of the Ca 2+ form (Lewait CNP90 of the firm Bayer). The raw water flows from the inlet 13 via a pump 14 and a jet bottom 15 as well as a support layer 16 of quartz sand through the catalyst 12 . By means of the pump 14 the catalyst bed is permanently fluidized (circulation) via the check valve 18 and the pump 14 . The constant flow and friction of the catalyst granules prevents blockage of the granules and additionally enhances the detachment of the crystal seeds from the catalyst surface. The crystal seeds are carried out by the removal of water (line 17 ) as crystallization seeds into the attached installation system.
Example 2
A catalytically active material prepared such is especially suitable as a bottom deposit for a method for treatment of water as disclosed in German patent DE 19606633 A1.
In the decarbonization of drinking water with high calcium carbonate contents by means of pH value increase with Ca(OH) 2 (typical pH values>12), the following method disadvantages are known:
High turbid substance contents in the overflow water of the reactor and thus the necessity of a filtration stage downstream.
High pH value of the product water must be lowered with great expense.
High use of chemicals.
By using a catalytically active material (for example, weakly acidic cationic exchanger of the Ca 2+ form) in the reactor, the above-mentioned disadvantages can be practically completely prevented. The pH value must only be raised minimally (to a maximum of 9) in order to generate at the catalytic surfaces a sufficient seed formation. Accordingly, primarily chemicals, a filtration stage and neutralization stage can be saved.
In the embodiments illustrated in FIGS. 3 and 4, the water treatment by means of a catalytically active ion exchange material 12 , which is arranged in a container 11 , is combined with a preferably physical water treatment device 19 . Such a physical water treatment device can operate, for example, electrostatically. Water treatment devices as they are described in the international application WO 95/to 6931 and the German patent application DE 19606633 are especially suitable.
Advantageosuly, the water to be treated, especially for decalcification, is guided by pump 14 in circulation through the ion exchange material. The water treatment device 19 can either be mounted within this circuit (FIG. 3) or can be arranged downstream of this circuit (FIG. 4 ). | In a method for precipitating or flocculating substances out of a solution, the solution is brought into contact with at least one ion exchange material having a surface provided with functional groups loaded with counter ions. The precipitation or flocculation is effected catalytically without exchange of the counter ions for ions contained in the solution. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation-in-part application of Petitioner's earlier application Ser. No. 11/238,783 filed Sep. 29, 2005, entitled SYSTEM AND METHOD FOR INJECTING TREES.
BACKGROUND
[0002] Prior art methods of tree injection typically involve a two-step operation, which include cutting an opening in the tree with one device and then injecting the tree with a second device. Such a two-step process is time consuming and involves considerable manual effort. Moreover, as the operation involves two steps, there is a delay between making the cut in the tree and introducing of the chemical to the cut, which is critical as trees have the ability to quickly heal incisions, protecting them from entry of bacteria or other such harmful organisms. The openings further allow for the entry of air into the tree. The air quickly expands inside the negative pressure of the sap, which typically disrupts the flow of sap in the area, preventing the thorough disbursal of injected chemicals. Furthermore, the air may introduce one or more types of harmful airborne fungi and bacteria.
[0003] Examples of prior art injection systems are found in Mauget, U.S. Pat. No. 3,304,655, and Barber, U.S. Pat. No. 2,116,591, which both disclose injection systems having a needle. However, the problem encountered in utilizing both examples of the prior art is that, before the needle may be inserted into a tree, a hole must be formed in the tree to prevent the needle from becoming plugged by tree fiber when it is inserted into the tree. Generally, at least a ⅛″ hole needs to be drilled in the tree to insert the needles of the above inventions, which causes a great deal of damage to a tree. Moreover, both of these prior art examples require the aforementioned two-step operation to achieve injection of a tree.
[0004] Other prior art injection methods require the use of implants at the injection site to facilitate the use of an injection device or to retain the injected chemicals within the tree. However, such implants are provided with large diameters that disrupt the flow of water and nutrients in the tree. Some implants are too large to allow the tree to sufficiently heal the area injured by the implant. Moreover, the size of such implants, combined with the hardened nature of the materials from which they are formed, may result in serious bodily injury to personnel who may need to later cut the tree down, due to disease, damage to the tree, or an emergency situation, such as a fire.
[0005] Accordingly, what is needed is a new system and method for injecting materials into trees that is relatively quick and efficient, while reducing the damage and disruption suffered by the tree. Moreover, such a system and method should not pose a risk of serious harm to personnel who must cut the tree down.
SUMMARY OF THE INVENTION
[0006] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter. Moreover, this Summary is not intended for use as an aid in determining the scope of the claimed subject matter.
[0007] A system and method of the present invention is provided for injecting materials into trees. The system is generally provided with an injection device, having forward and rearward end portions, an elongated needle that is removably coupled with the forward end portion, and a container for holding a liquid. The needle is provided with an open rearward end portion that is in communication with an open inner chamber and at least one ejector hole, which is formed in a side wall of the needle, adjacent a forward end portion of the needle. The needle is coupled with the injection device in a manner that permits the liquid to be selectively transferred from the container, through said needle, and out the one or more ejector holes. In one preferred embodiment the needle is provided in a small gauge and the one or more ejector holes are large enough to permit the passage of injectable liquids but small enough to self-seal when contacted by tree material. Another preferred embodiment associates a check valve with the needle that substantially prevents the flow of fluids from the tree through the needle.
[0008] The injection device is engaged with the tree trunk in a manner that injects the needle into the tree trunk so that the one or more ejector holes are positioned in contact with tree material, such as tree fiber and/or sap, located interiorly of the tree's outer bark layer and exteriorly of the heartwood portion of the tree. The liquid is injected into the tree trunk so that liquid is transferred from the container, through the injection device, through the needle, and out the one or more ejector holes. The injection device is then disengaged with the tree trunk and the needle so that the needle is at least temporarily left within the tree trunk.
[0009] It is therefore a principal object of the present invention to provide an improved system and method for injecting trees.
[0010] A further object of the present invention is to provide an improved tree injection method that will cause relatively little damage to a tree.
[0011] Still another object of the present invention is to provide a tree injection method that incorporates the use of expendable injection needles that are left within a tree after fluids are injected into the tree.
[0012] Yet another object of the present invention is to provide a tree injection method that utilizes an injection needle having one or more ejector holes that are self-sealing when they come into contact with tree material.
[0013] A further object of the present invention is to provide a tree injection method that utilizes an injection needle having a check valve that, when used to inject liquid into a tree, substantially prevents the passage of the liquid out the tree through the injection needle.
[0014] Still another object of the present invention is to provide a tree injection method that does not require preparation of a tree with a cut or a hole prior to injecting the tree.
[0015] Yet another object of the present invention is to provide a system and method for tree injection that are relatively simple and inexpensive to manufacture and implement.
[0016] A further object of the present invention is to provide a tree injection method that is both time and cost efficient.
[0017] These and other objects of the present invention will be apparent to those having skill in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Non-limiting and non-exhaustive embodiments of the present invention are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.
[0019] FIG. 1 is a perspective view of one preferred embodiment of the tree injection system of the present invention and one preferred manner in which it may be used;
[0020] FIG. 2 is an isometric view of one preferred embodiment of an injection needle of the present invention;
[0021] FIG. 3 is a partial, cut-away view of a tree trunk having injection needles of the present invention disposed therein;
[0022] FIG. 4 is a partial, cut-away view of a tree trunk and further depicts one preferred embodiment of the tree injection system of the present invention and one manner in which it could be used to inject a liquid into a tree trunk and substantially retain said liquid within the tree trunk;
[0023] FIG. 5 depicts another preferred embodiment of the tree injection needle of the present invention and one manner in which it could be used to inject a liquid into a tree trunk and substantially retain said liquid within the tree trunk; and
[0024] FIG. 6 depicts yet another preferred embodiment of the tree injection needle of the present invention and one manner in which it could be used to inject a liquid into a tree trunk and substantially retain said liquid within the tree trunk.
DETAILED DESCRIPTION
[0025] Embodiments are described more fully below with reference to the accompanying drawings, which form a part hereof and show, by way of illustration, specific exemplary embodiments. These embodiments are disclosed in sufficient detail to enable those skilled in the art to practice the invention. However, embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. The following detailed description is, therefore, not to be taken in a limiting sense in that the scope of the present invention is defined only by the appended claims.
[0026] The injection system 10 of the present invention is generally provided with an injection device 12 , having a forward end portion 14 and a rearward end portion 16 . A container 18 or attachment made via hose to a container, should be provided for holding an injectable liquid. The container 18 should be operatively coupled with the injection device 12 so that the liquid disposed within the container 18 may be selectively dispensed through the injection device 12 . An elongated needle 20 , having an open rearward end portion 22 , is operatively coupled with the forward end portion 14 of the injection device 12 so that the rearward end portion 22 is placed in open communication with the injection device 12 and the container 18 . The needle 20 is further provided with an open inner chamber 24 that is in open communication with the rearward end portion 22 and at least one ejector hole 26 which is formed in a sidewall 28 of the needle 20 , adjacent a forward end portion 30 thereof. Accordingly, fluid is permitted to be selectively transferred in a first flow direction from the injection device 12 through the needle 20 and out the at least one ejector hole 26 .
[0027] In use, the injection system 10 is assembled and an injectable liquid is provided within the container 18 . An elongated needle 20 is then removably coupled to the forward end portion 14 of the injection device 12 . Injection system 10 is then placed closely adjacent the trunk of a tree having an outer bark layer that covers inner wood layers including an inner bark layer, a cambium layer, a sapwood layer and a heartwood portion. The forward end portion 30 of the needle 20 is placed against the outer bark layer of the tree. Injection system 10 may then be pushed forward, disposing the needle 20 at least partially within the tree trunk. Preferably, the needle 20 is inserted into the tree trunk so that the injector holes 26 are located interiorly of the outer bark layer and exteriorly of the heartwood portion of the tree trunk.
[0028] With the injection system 10 properly in place, the individual may then inject the liquid into the tree trunk so that the liquid is transferred from the container 18 through the injection device 12 , through the needle 20 and out one or more of the ejector holes 26 . Means should be associated with the needle 20 that substantially prevents the liquid from flowing in an opposite, second flow direction out the needle 20 once the liquid is transferred out the ejector holes 26 into the tree. In one preferred embodiment, the one or more ejector holes 26 are shaped and sized to be self-sealing during an injection process. Specifically, the ejector holes 26 should be sized and shaped to permit the passage of the injectable liquid while being too small to allow the passage of tree material, such as tree fiber, therethrough. Experimentation with various diameters of ejector holes 26 has demonstrated that ejector holes having a diameter greater than approximately 0.02 inches permits the passage of injectable liquids but are not self sealing. In such an instance, the tree sap and injectable liquid will pass the ejector holes 26 , into the open inner chamber 24 and out the open rearward end portion 22 of the needle 20 . To the ability of the tree to expel foreign material, it is possible that substantial quantities of the injected liquid may be expelled from the tree along with tree sap. However, ejector holes 26 provided with a diameter of approximately 0.02 inches and smaller allowed the passage of injectable liquids but not tree sap. Accordingly, as the injectable liquid is disbursed into the tree trunk, natural tree material such as tree fiber and oftentimes sap comes into contact with the injector holes 26 and effectively seals the injector holes 26 , substantially prevented the passage of tree sap or the injectable liquid into the open inner chamber 24 and out the open rearward end portion 22 of the needle 20 .
[0029] In another preferred embodiment, the means for preventing the liquid from flowing in an opposite, second flow direction out the needle 20 is comprised of a check valve that is associated with the needle 20 . It is contemplated that several different forms of check valves may be used. In one example, depicted in FIG. 5 , the check valve is comprised of a valve 32 , a seat 34 and a spring 36 . The spring 36 is positioned to bias the valve 32 in a closed position (depicted) against the seat 34 and yield in response to liquid being transferred by the injection device 12 in the first flow direction through needle 20 . The check valve may also be provided with a stem 38 that extends outwardly from the check valve, in a rearward direction, when the valve 32 is in the closed position. This provides a user with the ability to push the stem 38 in a forward direction to move the valve 32 into its open position and detect whether or not fluid is flowing in the second flow direction. It will be advisable to leave the needle 20 in its injection position when such fluid flow is detected. However, where minimal flow is detected, the needle may be removed from the tree without significant concern that the liquid will escape from the tree. In another example, depicted in FIG. 6 , the check valve may simply be comprised of a ball-shaped stop 40 that is movable between a closed position adjacent a seat 42 at the rearward portion of the check valve and an open position toward a forward portion of said check valve. A spring 44 may be used to bias the ball-shaped stop 40 toward the seat 42 but yield in response to liquid being transferred by the injection device 12 in the first flow direction through needle 20 . When desirable, the means may be comprised of one or more ejector holes 26 , having a diameter greater than approximately 0.02 inches, and a check valve.
[0030] It is contemplated that the needle 20 may be disposed at various depths within the tree to attain a successful injection. However, it will be preferred that the needle 20 be inserted into the tree trunk so that at least one or more ejector holes 26 is located within the sapwood layer of the tree trunk, which will facilitate an adequate dispersal of the injectable liquid throughout the tree. Once the liquid has been injected into the tree, the user may simply disengage the injection device 12 with the tree trunk and the needle 20 so that the needle 20 is at least temporarily left within the tree trunk. It is contemplated that the needle 20 could be left within the tree trunk indefinitely. Constructing the needle 20 of stainless steel or a sufficiently rigid polymer will limit the disruption or contamination of the injected tree. Moreover, forming the needles 20 so that they are roughly 14 gauge in size or smaller will allow the needles 20 to be successfully inserted into most trees without bending or fracturing the needles 20 . Moreover, 14 gauge and smaller needles left within a tree will pose little, if any, risk to cutting implements, such as a chainsaw, used to later cut the tree down for any reason. However, it is contemplated that an individual injecting the tree could simply wait a small amount of time, such as a half an hour, and remove the needle 20 entirely. The amount of time required to leave the needle in place will depend upon the time of the year and the type of tree being injected. Some trees, at various times of the year, may require longer periods of time in order to disperse the injected fluid to permit removal of the needle 20 .
[0031] Although the invention has been described in language that is specific to structural features and/or methodological steps, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific features or steps described. Rather, the specific features and steps are described as forms of implementing the claimed 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. | A system and method for injecting liquids into trees is provided with an injection device having a liquid container and a removable needle. The system positions the needle into the sapwood of the tree. Liquid is injected into the tree through ejector holes in the needle. The ejector holes may be sized to prevent the liquid from reentering the needle once the ejector holes engage tree material. A check valve may be associated with the needle to substantially prevent the liquid from exiting the tree through the needle. The needle may be permanently left in place or removed after the liquid disburses into the tree. | 0 |
BACKGROUND OF THE INVENTION
The present invention concerns a sterile packing and a sterilization method using this packing.
Some activities involve transporting sterile parts or components in sterile packing. This is the case in particular for the component parts of syringes, which must be transported between the production site and an assembly site, to form the syringe, and fill the syringe bodies.
A known sterilization method used for syringe parts consists of placing these parts in packings made of a flexible and airtight material, then exposing these packings thus filled to gamma rays. This method has the drawback, for the syringe manufacturer, of having to pack the non-sterilized parts in non-sterile packings, then to transmit these packings to a service provider specialized in this type of sterilization, which, after sterilization, transmits these packings to the purchaser of the parts, for assembly and/or filling of the syringes. The use of a specialized sub-contractor of this type constitutes a notable constraint for the syringe manufacturer.
Another known sterilization method in such an application uses water vapor to sterilize the parts and their packing. This sterilization method is preferred to the radiation sterilization method because it is well-received by the pharmaceutical industry using the syringes, or even required by some users, or is also made obligatory by the nature or material of the packed parts or components. There are not, however, packings making it possible to ensure the perfect performance of sterilization during the sterilization method and, after transport, the perfect preservation of the integrity of the packing all the way to the end user.
BRIEF SUMMARY OF THE INVENTION
The present invention aims to resolve the abovementioned drawbacks.
Its aim is therefore to provide a packing making it possible to ensure the perfect performance of a sterilization of one or several objects to be sterilized, in particular through water vapor, to ensure perfect preservation of sterility during transport and storage of the packing, and to immediately detect any loss of integrity of the packing, and therefore any loss of sterility thereof. The invention also aims to provide a sterilization method using this packing, making it possible to sterilize said objects whiles ensuring the perfect performance of the sterilization thereof.
The term “object” will be used below generically to generally designate one or several parts or components to be packed; this term must be understood in the broadest sense, covering all types of part(s), product(s) or component(s), and in particular all component parts of syringes.
To achieve the abovementioned objectives, the packing according to the invention comprises:
a container for holding said at least one object to be sterilized, having an inlet opening and a discharge opening via which said at least one object may pass into and out of said container, said container comprising a rigid part which comprises a peripheral wall bored with a multitude of small holes having dimensions smaller than those of the said at least one object, and a non-rigid part in a material porous to the sterilization fluid and non-porous to microbial contamination, this non-rigid part being able to contain said rigid part and to be sealed thereon; and at least one envelope made in a flexible and airtight material, which is vacuum sealing fitted on said container.
The sterilization and packing method according to the invention comprises the steps consisting of:
in any order:
filling said rigid part of the abovementioned container with at least one object to be sterilized; closing said inlet opening and said discharge opening using said non-rigid part;
sterilizing the container using said sterilization fluid; placing the container, thus sterilized, in said at least one envelope; creating a vacuum inside said at least one envelope, and sealing this at least one envelope around the container while the vacuum inside said at least one envelope is maintained.
The invention thus consists of using a container comprising a rigid part bored with a multitude of holes through its wall, to receive the object(s) to be sterilized. The rigidity of this rigid part makes it possible to preserve the integrity of this or these object(s) during the later vacuum operation, which is necessary when this or these object(s) are liable to deform or deteriorate under the exertion of prolonged mechanical stresses exerted on them, as is the case for example for syringe plungers. This rigidity also has the advantage of granting a fixed shape to a set of objects, optimized for a homogenous exposure to a sterilization fluid, in particular water vapor, which is a crucial parameter for the performance of such a sterilization. In other words, said rigid part makes it possible to eliminate any piles of objects which would be made possible with a flexible container, causing a risk of the fluid not sufficiently penetrating to the heart of this pile to ensure the required sterilization. The rigidity of said rigid part also has the advantages of making it possible to increase the capacity of a packing relative to the maximum capacity which a known flexible packing can have, and to facilitate the treatments and manipulations done by operators.
The multiple openings of this rigid part of the container and the porosity of said non-rigid part allow a sufficient diffusion of the sterilization fluid inside said non-rigid part, said rigid part and around all of the objects contained in this rigid part; the closing of the non-rigid part by sealing makes it possible to preserve the integrity of the sterilization done to the objects, said rigid part and the internal surface of the non-rigid part.
Placing the packing under vacuum using said envelope makes it possible to perfectly protect the object(s) with regard to the environment, and the application of this envelope around the container constitutes an indication of the absence of penetration of air inside this container, and therefore indicates the preservation of the sterility of the packing.
The packing and the method according to the invention thus have the determining advantages of allowing effective sterilization of objects by a sterilization fluid, in particular by water vapor, perfectly preserving the integrity of these packed objects, and making it possible to immediately indicate any loss of integrity, and therefore sterility, of the packing.
The material of said at least one first membrane comprises pores whereof the size can go from 2 to 15 microns and a Log Reduction Value (as defined in the ASTM F-1608 standard) greater than or equal to 3. This can be a film marketed by the company Du Pont De Nemours under the TYVEK® brand, references 1073B, 2FS or 1059B, or the complex marketed by the company WIPAK under the WIPAK® brand, references Paper 80B or Paper 120B.
Preferably, the container includes a connection ring on its discharge opening, or close to this discharge opening, able to be connected to a sterile enclosure wherein said at least one object is intended to be transferred, and being located inside said at least one envelope.
The connection of the container to said sterile enclosure for the transfer of objects into this enclosure can, thanks to this ring, be done under the best conditions, the transfer being perfectly aseptic and ensuring the maintenance of sterility during its progress.
Said connection ring can in particular be of the type described in documents U.S. Pat. No. 6,571,540 and U.S. Pat. No. 6,817,143.
Said non-rigid part can be separated from this connection ring, or can be sealably connected to this connection ring.
Said rigid part of the container can be connectable at least to one part of said connection ring, to allow a facilitated discharge of the object(s).
In this case, advantageously, the part of the connection ring which is not connected to said rigid part of said container is contained in a sterile envelope. This sterile envelope is open so as to uncover the connection ring in order to allow the connection of this ring to the sterile enclosure.
Said rigid part of said container can be able to be separated from said connection ring.
Said rigid part of the container can be able to be connected to said connection ring via connection means. In this case, advantageously, said connection means are such that they maintain said rigid part of the container in a position coaxial to said connection ring.
This coaxial maintenance facilitates the discharge of objects into said sterile enclosure when said connection ring is connected to this enclosure.
The wall of the container defining said discharge opening can be formed to engage with said connection ring.
Said connection ring can also comprise a removable door, intended to be removed after connection of said ring to the sterile enclosure.
The sterile packing can also comprise a lid able to be connected to said rigid part of the container.
In the packing according to the invention, said non-rigid part can be formed of a plurality of layers.
This plurality of layers minimizes the risk of a loss of integrity of the packing if a hole appears in one layer. Moreover, the risk of having aligned holes decreases as the number of layers increases.
The invention will be well understood, and other characteristics and advantages thereof will appear, in reference to the appended diagrammatic drawing, showing, as a non-limiting example, one preferred embodiment of the sterile packing it concerns.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
FIGS. 1 to 4 are very simplified cross-sectional views of different component pieces of this packing, during different successive phases of assembling these pieces;
FIG. 5 is a view of the sub-assembly shown in FIG. 4 , when it is placed in a sterilization enclosure;
FIG. 6 is a similar view of this same sub-assembly, placed in an envelope;
FIG. 7 is a similar view of the sterile packing, as it is obtained after vacuum sealing of said envelope on said sub-assembly;
FIG. 8 is a view of the packing after removal of said envelope and connection to a sterile enclosure, before opening of a removable door it comprises, and
FIG. 9 is a view of the packing similar to FIG. 8 , after opening of said door.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 7 shows a sterile packing 1 formed by a container 2 including a connection ring 3 and an exterior envelope 4 .
The container 2 is intended to contain one or several objects 5 to be sterilized, in particular component parts of syringes, and in particular syringe plungers. As shown more particularly by FIGS. 1 to 4 , it comprises an internal part formed by a container 6 and an external part formed by envelopes 7 and 8 .
The container 6 is rigid. It comprises a peripheral wall bored with a multitude of small holes 10 having dimensions smaller than those of the objects 5 . As shown by FIG. 1 , this peripheral wall defines, at one end, an upper opening 11 for allowing the objects 5 in and forms, at the other end, a conduit 12 ending by a lower opening 13 for the discharge of the objects 5 . The container 6 also comprises, set back from its upper edge, a flange 14 able to receiving a closing lid 22 , and, set back from its lower opening 13 , a flange 15 provided with a deformable peripheral skirt, forming a lock means.
The external envelope 7 is flexible. It has a tubular shape and is connected, at its lower part, to the connection ring 3 ; it is dimensioned to contain the container 6 and comprises an upper portion enabling it to be closed by sealing on the upper end of this container 6 , as appears in FIG. 4 .
This envelope 7 is made in a material porous to the sterilization fluid and not porous to microbial contamination. This material comprises pores whereof the size can go from 2 to 15 microns and a Log Reduction Value (as defined in the ASTM F-1608 standard) greater than or equal to 3. This can be a film marketed by the company Du Pont De Nemours under the TYVEK® brand, references 1073B, 2FS or 1059B, or a complex marketed by the company WIPAK under the WIPAK® brand, references Paper 80B or Paper 120B.
The envelope 8 is connected to the connection ring 3 and is dimensioned to completely envelop this ring 3 . It comprises a non-porous peripheral wall 8 a and an end wall 8 b , sealed on the peripheral edge of the wall 8 a , in a material porous to the sterilization fluid and not porous to microbial contamination. This material can in particular be the same as that constituting the envelope 7 .
The connection ring 3 comprises a circular seat 3 a and a removable door 3 b . The circular seat 3 a comprises means for the connection of the ring 3 to a sterile enclosure for manipulation of the objects 5 , and defines a central discharge opening for these objects 5 . The removable door 3 b is, at this stage of use of the packing 1 , maintained on the seat 3 a such that it covers said discharge opening 13 . This ring is of a known type, for example of the type described in documents U.S. Pat. No. 6,571,540 and U.S. Pat. No. 6,817,143, and therefore will not be described in more detail.
The connection ring 3 also comprises an extension 3 c integral with the seat 3 a , having a peripheral wall and a transverse wall. The peripheral wall comprises envelopes 7 and 8 sealed on it. The transverse wall defines an opening 20 coaxial to said central discharge opening defined by the seat 3 a; as shown in FIG. 2 , this opening 20 is intended to receive, through it, the discharge conduit 12 , until it comes from the lower end of this conduit bearing against the door 3 b , then the flange 15 . The skirt comprised by the latter locks by snapping behind said transverse wall at the moment when said discharge conduit 12 bears against the door 3 b . The container 6 is thus maintained in a position coaxial to the connection ring 3 .
Once this connection of the container 6 and the ring 3 is done, the container 6 is filled with objects 5 , as shown by FIG. 2 . Out of a concern for clarity in the drawing, these objects 5 have been only partially illustrated, the overall contour they form being defined by a dashed line.
The container 6 then receives the aforementioned closing lid 22 (cf. FIG. 3 ), whereof the assembly to the flange 14 can be done in particular by clipping, then the envelope 7 is sealed above this lid 22 , as shown in FIG. 4 .
The container 2 thus formed is placed in a sterilization enclosure 25 , as appears in FIG. 5 , wherein a sterilization fluid circulates, in particular water vapor. This fluid, shown by circular arrows, penetrates through the pores of the envelope 7 , through multiple holes 10 of the wall of the container 6 and through the pores of the wall 8 b of the envelope 8 , which allows a sufficient diffusion of this sterilization fluid inside the envelopes 7 and 8 , the container 6 and around the objects 5 . Once the sterilization is done, the closing of the envelope 7 by sealing makes it possible to preserve the integrity of this sterilization for the objects 5 , the container 6 and the internal surfaces of the envelopes 7 and 8 .
The envelope 4 , visible in FIG. 6 in the non-sealed state, is formed of a flexible and airtight material, in particular in a synthetic material. The sterilized container 2 is placed in this envelope 4 , then a vacuum is created inside the envelope 4 , and therefore also inside the envelope 7 and the container 6 ; the envelope 4 is then vacuum sealed on the container 2 , as shown in FIG. 7 , thereby making it possible to obtain the packing 1 .
This evacuation of this packing 1 thanks to the envelope 4 makes it possible to perfectly protect the objects 5 with regard to the environment, and the application of this envelope 4 around the container 2 constitutes an indicator of the absence of penetration of air inside this container 2 , and therefore an indicator of the preservation of the sterility of the packing 1 .
The rigidity of the container 6 makes it possible to preserve the integrity of the objects 5 during the evacuation operation, which is necessary when these objects are liable to deform or deteriorate under the exertion of the prolonged mechanical stresses exerted on them, as is the case for example for syringe plungers. This rigidity also has the advantage of granting a fixed shape to the assembly formed by these objects, optimized for a homogenous exposure to the sterilization fluid, which is a crucial parameter for performance of the sterilization. In other words, the container 6 makes it possible to eliminate all piles of objects which would be made possible with a flexible container, causing a risk of the fluid not sufficiently penetrating to the heart of this pile to ensure the required sterilization. The rigidity of the container 6 also has the advantages of making it possible to increase the capacity of a packing relative to the maximum capacity which a known flexible packing can have, and facilitating the treatments and manipulations done by operators.
The transfer of the objects 5 into a sterile enclosure 30 as shown in FIGS. 8 and 9 is done by opening and removing the envelope 4 , then opening the envelope 8 , connecting the seat 3 a of the ring 3 to the corresponding seat arranged on the enclosure 30 (cf. FIG. 8 ), then opening the door 3 b (cf. FIG. 9 ). The connection of the seat 3 a to the seat of the enclosure 30 is facilitated by the bearing of the packing 1 on a support 31 placed in the appropriate place.
In reference to FIG. 9 , it appears that the mobility of the rigid container 6 in the flexible envelope 7 makes it possible to engage the discharge conduit 12 through the central discharge opening defined by the seat 3 a , and therefore to preserve the objects 5 from all contact with a potentially contaminated surface of this seat 3 a or of said corresponding seat of the enclosure 30 . As appears from the preceding, the invention provides a sterile packing and a sterilization method using this packing, having the determining advantages of allowing an effective sterilization of the objects by a sterilization fluid, in particular water vapor, of perfectly preserving the integrity of the packed objects, and enabling an immediate indication of any loss of integrity, and therefore sterility, of the packing.
It must be specified that the embodiment of the invention described above was provided purely as an example. It goes without saying that the invention is not limited to this embodiment, but that it extends to all embodiments covered by the appended claims. | The packing according to the invention comprises: a container for holding said at least one object to be sterilized, having an inlet opening and a discharge opening via which said at least one object may pass into and out of said container, said container comprising a rigid part which comprises a peripheral wall bored with a multitude of small holes having dimensions smaller than those of the said at least one object, and a non-rigid part in a material porous to the sterilization fluid and non-porous to microbial contamination, this non-rigid part being able to contain said rigid part and to be sealed thereon; and at least one envelope made in a flexible and airtight material, which is vacuum sealing fitted on said container. | 0 |
This is a continuation of application Ser. No. 581,062, filed May 27, 1975, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process for producing a microporous sheet. More particularly, the present invention relates to a process for producing a microporous sheet for filtration which permits the flow of a large amount of a fluid.
2. Description of the Prior Art
A microporous sheet, i.e., a sheet containing fine pores in one surface thereof is well known (e.g., C. Gelman et al, Anal. Chem., 37 (6) 29 A (1965)), and widely used as a filter and the like.
In general, a microporous sheet is produced mainly from a cellulose ester, a cellulose ether, regenerated cellulose, polyvinyl chloride, polyacrylonitrile, polyamide, alginate, gelatin, or the like, as described in U.S. Pat. Nos. 1,421,341, 3,133,132, 2,944,017, 2,783,894, Japanese Patent Publication Nos. 15698/1968, 33313/1970, 39586/1973, 40050/1973, Sartorius Membrane Catalog (1970), Gelman Catalog (1969), etc. The pore size of the fire pores in microporous sheets produced by prior art techniques generally ranges from about 0.01 μ to about 8 μ, and this range is practical for use in filtration. That is, the features of the so-called membrane filter reside in that the pore size is generally uniform as compared with other filters, the porosity is high, and the filtration resistance is low.
However, conventional membrane filters have the disadvantages that the amount of particles retained is small and the pores of the filters become rapidly packed since the filters separate the particles only on the surfaces thereof.
Thus microporous sheets have been desired which retain a large amount of particles, permit the flow of a large amount of a fluid, and whose pores become packed slowly.
As a result of investigations on these microporous sheets, it has been now been found that in hitherto produced membrane filters, the pore size changes discontinuously in the thickness direction of the sheet. That is, when a membrane filter is produced by the above described prior art technique, the pore size of the filter obtained changes continuously in a trumpet-shaped form in the thickness direction. For example, FIG. 1 is a sectional view of a conventional membrane filter in which the hatched areas indicate the non-pore areas. In the conventional membrane filter the pore size at Surface B is about 1 to 2 times larger than the pore size at Surface A and the pore size at the inner portion of the filter is about 2 to 100 times larger than that at Surface A.
Therefore, it can be seen that the pores become packed with particles at the narrow portions of the filter, i.e., at the surface thereof regardless of whether the fluid is passed from either Surface A or Surface B. As a result of recent investigations based upon these findings, it has been further found that a microporous sheet containing the pores in the form of a trapezoid can be quite conveniently produced by splitting a microporous sheet along a plane perpendicular to the thickness direction of the sheet.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a process for the production of a microporous sheet which retains a large amount of particles, permits the flow of a large amount of a fluid, and whose pores do not become packed rapidly with particles.
The object can be attained by peeling off a microporous sheet comprising a solvent-soluble resin bonded to a plate from the plate in such a manner that the microporous sheet is split into two sheets along a plane perpendicular to the thickness direction of the sheet.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an enlarged sectional view of a microporous sheet produced by a conventional method.
FIGS. 2 to 4 are sectional views of embodiments of the present invention showing the peeling operation.
FIG. 5 is an enalarged sectional view showing the surface of a microporous sheet produced by the method of the present invention.
FIG. 6 is a sectional view of a conventional microporous sheet provided with a pre-filter.
DETAILED DESCRIPTION OF THE INVENTION
The separation of a microporous sheet along a plane perpendicular to the thickness direction into two sheets can be achieved either by bonding the microporous sheet onto a plate to which the microporous sheet adheres quite well, and then peeling off the microporous sheet, or by casting a polymer solution on a plate having good adhesivity to form the microporous sheet on the plate, and then peeling off the microporous sheet so produced. Thus the term "bond" as used herein designates the state that the microporous sheet adheres, coheres, or attaches onto the plate temporarily.
As the plate, any of those plates which have smooth surfaces and are capable of supporting the microporous sheet, preferably without any separation between the plate and the microporous sheet, can be used. These supports include glass plates, metal plates, sheets of synthetic resins such as polyvinyl chloride, polyvinylidene chloride, polystyrene, polymethacrylates, polyacrylamides, polyethylene, polypropylene, polyamides, polycarbonates, cellulose esters, polyesters, and the like, and paper, and the laminates thereof. From the standpoint of operation, a flexible sheet is particularly preferably used.
Methods for improving the adhesion of the plate to the microporous sheet can be divided roughly into two groups. One method is a physical or chemical treatment, or a combination thereof, and the other method is the coating of an adhesive on the support, or a combination of the above treatment and a coating of an adhesive on the support.
The former method is mainly employed with synthetic resin sheets and includes corona discharge, UV irradiation, washing with an alkali or acid, etc., as described in U.S. Pat. Nos. 2,943,937, 3,475,193, 3,615,557, 3,590,107, British Pat. No. 1,215,234. The latter method is a practical method which can be widely used regardless of the kind of support. These methods are well known in the field of a synthetic resin sheets.
The adhesive as used herein can be any of those which can sufficiently bond the plate and the microporous sheet. These adhesives include starch, dextrin, gelatin, polyvinyl acetate, cellulose esters, melamine condensates, epoxy resins, polyvinyl alcohol, neoprene rubber, silicone rubber, polyesters, and the like. Although the adhesive used changes depending upon the kind of the support and the material of the microporous sheet, a suitable adhesive can be easily selected by one skilled in the art through simple routine experiments.
On the other hand, the microporous sheet which is produced directly or using an adhesive on the support can be easily produced by casting or coating a polymer solution according to the prior art technique. Polymer solutions and various operations used in the production of the microporous sheet are described in the above described patents, and U.S. Pat. Nos. 3,129,159, 3,428,584, etc.
The hitherto known binders, additives, and methods such as casting, drying, and the like can be also conveniently utilized in the present invention, e.g., as described in U.S. Pat. No. 3,547,809 and Japanese Pat. No. 40,050/73.
The microporous sheet thus formed on or bonded to the support can suitably have pores of a size of about 0.01 to 10 μ on either surface thereof and pores of a size of about 0.1 to 8 μ are preferred. The pores in the interior of the microporous sheet will in general range from about 2 to 100 times larger than those pores on the surfaces.
The microporous sheet bonded onto the support as described above is peelled off of the support. The peeling step in the method of the present invention is important in obtaining a membrane filter containing relatively large pores. However the peeling operation is not particularly limited. The simplest peeling operation comprises bending the support or the microporous sheet at an acute angle with each other to provide a strain based upon the difference in the radius of curvature between the support and the microporous sheet. If the adhesive strength between the support and the microporous sheet is sufficient, the microporous sheet is subject to an internal cleavage, thereby resulting in a splitting of the sheet into two sheets along a plane at a right angle to the thickness direction. This is considered to be due to the fact that the part with a large pore size inside the microporous sheet is thin and weak in strength.
The present invention will be further explained by reference to the accompanying drawings.
FIGS. 2 to 4 show embodiments of peeling off the microporous sheet in accordance with the method of the present invention.
In FIG. 2, the microporous sheet 2 bonded to the plate 1 is peeled off by bending using a roller 3.
In FIG. 3, the microporous sheet 2 is peeled off from the plate 1 by bending the microporous sheet using a suction drum 4, and by bending the plate using a peeling bar 5.
In FIG. 4, the microporous sheet 2 bonded to the plate 1 is separated at the position where the inner pore size is large, into a microporous sheet (article) 2a and a microporous sheet (non-article) 2b. The microporous sheet 2b becomes a microporous sheet (article) 2a when peeled off from the plate 1, but it can be discarded as it is.
With the thus produced microporous sheet, as shown in FIG. 5, the ratio of the pore size at Surface A to that at Surface B can be made about 1:2 to 1:100, preferably 1:4 to 1:100. When the microporous sheet is used for filtration, the layer containing the pores which are large in the pore size acts as a prefilter to separate relatively coarse particles in the mother liquor and the layer containing the pores which are small in the pore size acts to separate much smaller particles, and thus the packing of the filter is delayed and the amount of the fluid which can be passed is increased up to about 1.5 to 5 times larger than the amount which can be passed through a conventional filter.
On the other hand, with a membrane filter having a prefilter on one side of a filter paper or filter cloth produced by the method as described in Japanese Patent Publication No. 19217/1973, as shown in FIG. 6, a microporous member (prefilter) 6 is provided with a layer (membrane filter) 7 containing a large number of fine pores, and thus a portion of the fine pores of the membrane filter 7 becomes packed with the particles on the surface of the prefilter 6. Therefore, with the filter as shown in FIG. 6, the filtration rate is decreased to about 30 to 40% as compared with the case where the membrane filter is used alone.
The microporous sheet produced by the method of the present invention is substantially a single element and the pore shape changes continuously in the form of a trapezoid in the direction of the thickness of the layer. Thus, since the pores, which are contained in the prefilter and which are large in pore size, are continuously connected to the pores, which are contained in the memberane filter and which are small in the pore size, all of the fine pores pass through the filter from the surface to the opposite surface. Therefore, with the microporous sheet of the the present invention, the filtration rate is substantially the same as that of a microporous sheet produced by the conventional method, and the packing is slow and the amount which can be filtered is large.
That is, since the microporous sheet produced by the method of the present invention has an excellent capability for retaining the particles and is slow to be packed at the time of filtration, the microporous sheet is capable of being used to filter a large amount of the fluid. Thus, the microporous sheet produced by the method of the present invention can be used for general cleaning and filtration, for the removal of bacteria and stabilization of liquidous foodstuffs such as beer, wine, sake, juice, and the like, the purification of air, the complete removal of bacteria from pharmaceuticals, the ultrafiltration of proteins, the filtration of photoresist solutions, the detection and analysis of bacteria, the inspection of waste water, and the like, and further it can be used as a membrane for electrophoresis and as a reverse osmosis membrane.
The present invention will be explained in greater detail by reference to the following examples. All parts, percents, ratios and the like are by weight unless otherwise indicated.
EXAMPLE 1
______________________________________Composition 1 Parts______________________________________Cellulose Acetate 6(degree of acetylation: 39.6)Glycerin 1Methylene Chloride 54Methanol 35Water 5______________________________________
The above components were mixed to produce a uniform solution, which was divided into two portions.
One of these portions was cast onto a stainless steel plate which was coated with nitrocellulose as an adhesive in a thickness of about 1 μ (method of the present invention), and the other portion was cast onto a stainless steel plate which was not subjected to any treatment (conventional method). The thus coated stainless steel plates were dried at room temperature (i.e., 20° to 30° C) for 2 hours and then at 80° C for 30 minutes, and thus microporous sheets having a film thickness of about 120 μ were formed on the stainless steel plates. Then the microporous sheets were peeled off in the same manner as shown in FIG. 2.
The microporous sheet produced by the method of the present invention was peeled off, as shown in FIG. 4, leaving a part of the microporous sheet having a thickness of about 10 μ on the plate 1. At this time, the volatile content of the sheet was 0.5%. The properties of the thus obtained microporous sheet are shown hereinafter.
EXAMPLE 2
Microporous sheets were produced by the same method as used in Example 1. The microporous sheets were saponified at 23° C for about one hour using a 1N NaOH aqueous solution, washed with water, and dried to produce microporous sheets of regenerated cellulose. In each case, the degree of acetylation was about 0.4.
EXAMPLE 3
______________________________________Composition 2 Parts______________________________________Nitrocellulose 15Methyl Formate 44Ethanol 33Water 7Polyoxyethylene Octylphenyl Ether 1______________________________________
The above components were mixed to produce a uniform solution, which was then divided into two portions.
One of these portions was cast onto a glass plate which was coated with cellulose acetate in a thickness of about 0.5 μ, and the other portion was cast onto a glass plate which was not subjected to any treatment. The thus coated glass plates were dried at room temperature for one hour to produce microporous sheets having a thickness of about 160 μ thereon. The microporous sheets so produced were peeled off from the glass plates using the method as shown in FIG. 2.
The microporous sheet produced by the method of the present invention provided a microporous sheet having a thickness of about 130 μ. At this time, the volatile content of the microporous sheet so obtained was 25% , and the volatile content was reduced below 1% by heating at 100° C for one hour.
EXAMPLE 4
______________________________________Composition 3 Parts______________________________________Alcohol-soluble Nylon 16(CM 4000, trade name, produced byToray Industries, Ltd.)Methanol 50Water 23Dioxane 10______________________________________
The above components were mixed to produce a uniform solution, which was then divided into two portions. One of these portions was cast onto a polyethylene terephthalate (PET) sheet which was coated with a vinyl acetate resin, and the other portion was cast on an untreated PET sheet. The thus coated PET sheets were dried at 23° C for 5 hours and then at 90° C for 40 minutes to form microporous sheets having a thickness of about 200 μ thereon. The microporous sheets so produced were peeled off by the use of a suction drum and a peeling bar as shown in FIG. 3 and thus microporous sheets having a thickness of about 120 μ were obtained. In the former microporous sheet, a part of the microporous sheet remained on the plate as shown in FIG. 4.
EXAMPLE 5
A microporous sheet of polyvinyl chloride was produced on an untreated glass plate, and the micropropous sheet so produced was divided into two sheets. One the side of one of the sheets which had been in contact with the glass plate, an adhesive tape was bonded and then peeled off. The surface layer which was bonded to the tape was also peeled off.
The properties of the sheets as produced in each of the above examples are shown in Table 1 below.
Table 1__________________________________________________________________________ Example 1 Example 2 Example 3 Example 4 Example 5 A.sup.(1) B.sup.(2) A B A B A B A B__________________________________________________________________________Pore Size (μ).sup. (3) 0.5 0.5 0.4 0.4 0.8 0.8 1.0 1.0 0.6 0.6Initial Filtration.sup.(4)Rate 90 50 60 40 60 50 60 40 50 35Average Filtration.sup.(5)Rate 30 6 20 5 16 9 29 14 17 8__________________________________________________________________________ .sup.(1) A Produced by the method of the present invention .sup.(2) B Produced by the conventional method .sup.(3) Pore Size Average pore size on the side which was not in contact with the plate, measured by the mercury injection method. .sup.(4) Initial Filtration Rate Filtration amount (ml/cm.sup.2 /min) during the initial one minute of filtration of beer which had not been subjected to any filtration treatment after fermentation and filtered under a pressure of 1 Kg/cm.sup.2. .sup.(5) Average Filtration Rate Average filtration amount (ml/cm.sup.2 /min) over a 20 minute using beer which had not been subjected to any filtration treatment after fermentation as described above under a pressure of 1 Kg/cm.sup.2.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | A process for producing a microporous sheet comprising peeling off a microporous sheet of a resin bonded to a plate from the plate in such a manner that the microporous sheet is split into two sheets. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a method for the manufacture of rigid packets with a hinged lid.
The present invention has particular advantages for the tobacco industry in the area of cigarette packets and their manufacture, the art field to which reference is made directly in the following specification albeit with no limitation in scope implied.
A cigarette packet of the rigid type with a hinged lid is fashioned conventionally from a precreased diecut blank exhibiting a central longitudinal portion, and two lateral portions each consisting in a succession of lateral longitudinal flaps; the steps of the relative manufacturing process include directing the blank along a predetermined path and into a folding unit, then pairing each blank with a relative frame internally of the folding unit and bending the blanks and frames in such a way as to turn out a succession of respective packets.
In general, each packet comprises a container of cupped appearance and a lid, likewise of cupped appearance, hingedly attached to an open top end of the container; the central portion of the relative blank comprises a succession of panels proportioned and positioned to generate front panels, end panels and rear panels of both the container and the lid. The two panels coinciding with the rear wall of the container and the rear wall of the lid are joined on either side to respective longitudinal flaps, which when bent ultimately at right angles to the corresponding panels will constitute an internal layer of a respective side wall of the packet.
Two distinct problems can arise typically during the formation of a packet from a blank as described above: the first deriving from the need for the two side wall inner flaps to be positioned correctly in relation one to another, and in particular the need to avoid overlapping contact between the adjoining edges of the two flaps on either side; the second from the need for the frame to remain positioned correctly in relation to the blank while the blank is being bent and folded.
The object of the present invention is to provide a simple and economical manufacturing method in which the two problems outlined briefly above can be overcome at one and the same time.
SUMMARY OF THE INVENTION
The stated object is realized according to the invention in a method for manufacturing rigid packets with a hinged lid fashioned from relative diecut blanks presenting a central longitudinal portion and two lateral portions, each consisting in a succession of longitudinal lateral flaps, which includes the steps of advancing the blanks along a predetermined path to a folding unit and, internally of the folding unit, associating each blank with a relative frame and bending the blanks and frames in such a way as to fashion respective packets.
In the method disclosed, the blanks are directed in succession between two mutually opposed and contrarotating incision rollers of a cutting and impressing unit located along the feed path, preceding the folding unit in a direction followed by the blanks along the selfsame path, of which the two rollers are embodied with matching profiles positioned and timed to engage each lateral portion of the blank, impinging on a respective pair of adjoining flaps which when bent to a right angle will ultimately constitute an internal layer of one flank wall of the packet, and designed to fashion at least one bend formed in one flap of the pair near an end adjacent to the remaining flap, and an inwardly directed projection formed on a first flap of the pair that is disposed permanently in contact with the relative frame of the finished packet.
The present invention also relates to a machine for the manufacture of packets with a hinged lid utilizing relative diecut blanks having a central longitudinal portion and two lateral portions, each consisting in a succession of longitudinal lateral flaps; such a machine typically comprises a folding unit internally of which each blank is associated with a relative frame and by which the blanks and frames are fashioned into respective packets, also feed means by which the blanks are directed along a predetermined path to the folding unit. The machine according to the invention also comprises a cutting and impressing unit located along the feed path, preceding the folding unit in a direction followed by the blanks along the feed path, consisting in two mutually opposed and contrarotating incision rollers embodied with matching profiles positioned and timed to engage each lateral portion of the blank, impinging on a respective pair of adjoining flaps which when bent through a right angle will ultimately constitute an internal layer of one flank wall of the packet, and designed to fashion at least one bend formed in one flap of the pair near an end lying adjacent to the remaining flap, and an inwardly directed projection formed on a first flap of the pair that is disposed permanently in contact with the frame of the finished packet.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in detail, by way of example, with the aid of the accompanying drawings, in which:
FIG. 1 illustrates a preferred embodiment of the machine according to the present invention, shown schematically in perspective and with certain parts omitted for clarity;
FIG. 2 is an enlarged detail of FIG. 1;
FIG. 3 is the plan view of a diecut blank from which to fashion a rigid cigarette packet;
FIG. 4 is the partly exploded perspective view of a packet manufactured by a machine as in FIG. 1 and utilizing a blank as in FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference FIG. 4 of the drawings, 1 denotes a rigid packet accommodating a group of cigarettes (not illustrated) enveloped in a wrapper 2 (FIG. 1) of metal foil paper. The packet 1 presents the shape of a rectangular parallelepiped and comprises a container 3 of substantially cupped appearance with an open top end 4 and a lid 5 uppermost, also of cupped appearance, hinged to the container 3 and rotatable thus between open and closed positions in which the top end 4 is respectively exposed and concealed. The container 3 exhibits a front face 6 and a rear face 7, mutually opposed and parallel, two lateral or flank faces 8 disposed mutually parallel and perpendicular to the front and rear faces 6 and 7, and a bottom end face 9 disposed perpendicular to the remaining faces 6, 7 and 8.
In like manner the lid 5 exhibits a front face 10 and a rear face 11 mutually opposed and parallel, two flank faces 12 disposed mutually parallel and perpendicular to the front and rear faces 10 and 11 and a top end face 13 disposed perpendicular to the remaining faces 10, 11 and 12. The free edges 14 presented by the flank faces 12 of the lid 5 are offered respectively to the free edges 15 presented by the flank faces 8 of the container 3.
The packet 1 also comprises a frame 16 of U shape projecting in part from the open top end 4 of the container; the frame affords a central section 17 of which a lower portion is breasted in contact with the front face 6, and two lateral wings 18 bent at right angles in relation to the central section 17, disposed partially in contact with the corresponding flank faces 8 of the container 3 and terminating at the bottom in respective straight edges 19.
The packet 1 described briefly above is fashioned from a flat diecut blank 20 illustrated in FIG. 3. The blank 20 has a longitudinal axis 21 of symmetry and exhibits a plurality of transverse crease lines denoted 22, 23, 24, 25 and 26, and two longitudinal crease lines denoted 27 and 28. The surface area of the blank 20 is divided by the two longitudinal crease lines 27 and 28 into a central longitudinal portion 29 and two lateral longitudinal portions 30 one on either side of the central portion 29. The transverse crease lines 22. . .28 serve to establish a plurality of panels denoted where possible by the same numbers, primed, as are used to identify the corresponding parts of the packet 1.
More exactly, the transverse crease lines 22 . . . 26 combine with the two longitudinal crease lines 27 and 28 to establish a first end panel 10' extending as far as the line denoted 22, a first intermediate panel 13' extending between the lines denoted 22 and 23, a second intermediate panel 11' extending between the lines denoted 23 and 24, also a central panel 7' extending between the lines denoted 24 and 25, a third intermediate panel 9' extending between the lines denoted 25 and 26, and finally a second end panel 6' extending from this last line 26. All of the aforementioned panels 10', 13', 11', 7', 9' and 6' are compassed within the central portion 29 of the blank.
Each lateral portion 30 comprises a respective plurality of flaps 31, 32, 33 and 34 associated externally with and separated from the respective panels 10', 11', 7' and 6' by the two longitudinal crease lines 27 and 28. The flaps 32 adjoining the first intermediate panel 11' are extended to create longitudinal appendages 35 disposed alongside the first intermediate panel 13' and united with the flaps 32 by way of the relative transverse crease line 23. The single flap 32 is of substantially trapezoidal shape 7, compassed on the side nearest the adjoining flap 33 remote from the appendage 35 by an obliquely angled edge 36 disposed parallel and adjacent to a corresponding edge 37 of this same flap 33. Each of the flaps denoted 33 likewise is substantially trapezoidal in shape, compassed externally by a longitudinal edge denoted 38 and associated at the end remote from the obliquely angled edge 37, by way of the transverse crease line denoted 25, with a longitudinal appendage 39 located alongside the third intermediate panel 9'.
The remaining flaps 34 also are trapezoidal in shape, each terminating at the end remote from the corresponding appendage 39 in an obliquely angled edge 40 disposed parallel to the edge denoted 37. The flaps 33 and 34 associated with the larger panels 7' and 6' will be bent at right angles to these same panels and overlapped by rotating the panels 6' and 7' themselves convergently through 90° each in relation to the third intermediate panel 9', so as to form the two flank faces 8 of the container 3. The free edges 15 afforded by the flank faces 8 of the container 3 are therefore generated by the mutually aligned oblique edges 37 and 40 of the two longer flaps 33 and 34. The two appendages denoted 39 will be bent at right angles to the flaps 33 from which they extend and rotated convergently, together with the two flaps 33, to the point of assuming a position flush against the inside surface of the corresponding panel 9', with which they combine to form the bottom end face 9 of the container. In like manner, the edges 41 of the flaps 31 remote from the adjoining appendages 35 are angled obliquely and parallel to the respective edges denoted 36. The four flaps 31 and 32 are bent at right angles to the corresponding panels 10' and 11' and overlapped by rotating the two panels one toward another through 900 in relation to the first intermediate panel 13', so as to form the two flank faces 12 of the lid 5. The free edges 14 afforded by the flank faces 12 of the lid 5 are therefore generated by the mutually aligned oblique edges 41 and 36 of the paired flaps 31 and 32. The relative appendages 35 are bent at 90° to the flaps 32 from which they extend and rotated convergently together with the associated flaps 32 into a position flush against the inside face of the first intermediate panel 13', with which they combine to form the top end face 13.
As readily discernible in FIG. 4, the two adjacent flaps 32 and 33 on either side will combine when bent through a right angle to provide an internal layer 42 of one respective flank wall 43 of the packet 1, whereas the remaining and corresponding flaps 31 and 34 provide an external layer 44 of the flank wall 43 when bent to a right angle; also that each longer flap 33 forms a part of the internal layer 42 that will be breasted permanently, in the finished packet 1, with the wrapper 2 and with the relative wing 18 of the frame 16,.
To the end of ensuring that the frame 16 will be positioned correctly within the container 3, each longer flap 33 of the blank 20 exhibits a relative projection 45 designed to function as a locating element for the edge 19 presented by the relative wing 18 of the frame 16. Each such projection 45 is created by making a substantially transverse cut 46 in the respective flap 33 at a given point along the longitudinal edge 38, and fashioned by bending in a portion 47 of the flap 33 located on the side of the cut 46 nearer the relative appendage 39.
In an alternative embodiment, the projections 45 in question might be created by making a first cut 46 as described above in combination with a second transverse cut 46', indicated by a phantom line in FIG. 3, made at a point in each flap 33 close to the first cut 46. In this instance the projection 45 is formed by bending in the portion compassed between the two cuts 46 and 46'.
To make certain that the two flaps 32 and 33 of each pair do not overlap even minimally during the formation of the relative layer 42, a bend is made in each of the lid flaps 32 at one end, adjacent to the obliquely angled edge 36. The bend 48 serves to create an end portion 49 on the flap 32 taking up only a part of the relative edge 36, displaced from the plane occupied the flap 32 and providing a stop against which the edge 37 of the adjacent flap 33, which occupies the same plane, is bound to locate.
It will be appreciated that the bend 48 need not appear necessarily as a single crease delimiting an end portion 49 directed away from the wrapper 2, as in the example of the drawings; in an alternative embodiment (not illustrated), there might be two creases from which to initiate a first outward bend and a second bend directed toward the inside of the packet 1. Whatever the number and orientation of the bends, in any event, the important feature is that at least one portion of the flap 32 located along a part of the obliquely angled edge 36 should be displaced from the plane occupied by the flap 32 itself.
In a further alternative embodiment, likewise not illustrated, the partial overlap between the two flaps 32 and 33 in question might be prevented by fashioning the bend 48 in the longer flap 33.
With reference to FIGS. 1 and 2, a machine 50 for the manufacture of rigid packets 1 with a hinged lid comprises a conveyor 51 by which precreased diecut blanks 20 are caused to advance singly and in succession along a predetermined direction D1, following a path P that extends through a cutting and impressing unit 52 at which the aforementioned cuts 46 and bends 48 are made in each blank 20, and a folding unit 53 located on the path P at a point following the cutting and impressing unit 52 along the feed direction D1. In the example of FIG. 1, the blanks 20 are advanced by the conveyor 51 each with its longitudinal axis 21 disposed transversely to the feed direction D1.
As illustrated to advantage in FIG. 2, the cutting and impressing unit 52 comprises two contrarotating incision rollers 54 and 55 mounted in such a way as to rotate about respective axes 56 and 57 disposed transversely to the feed direction D1, parallel one with another and with a conveying surface 58 along which the blanks 20 are advanced by the conveyor 51 each with the inside face offered to the selfsame surface 58. The two incision rollers 54 and 55 are disposed substantially tangential to one another as well as to the conveying surface 58, one above and one below, and will be power driven so as to rotate synchronously about the respective axes 56 and 57 (counterclockwise and clockwise respectively as viewed in FIG. 2) at a peripheral velocity identical to the linear velocity V at which the blanks 20 advance along the feed direction D1.
The rollers 54 and 55 are embodied with essentially cylindrical and matching outer surfaces 59 and 60. For the purpose of making the cut denoted 46, in particular, the surface 59 of the one roller 54 is furnished with two dies 61, each of which affords a lateral cutting edge 62 disposed circumferentially in relation to the roller 54, whilst the surface 60 of the remaining roller 55 affords two sockets 63 each positioned to admit a corresponding die 61. The distance separating the two dies 61, measured circumferentially in relation to the roller 54, is substantially equal to the distance between the two edges 38 (effectively the width) of the blank 20, and the radial dimensions of the rollers 54 and 55 are such that when the surfaces 59 and 60 are set in contrarotation at a peripheral velocity equal to the linear velocity V of the blanks 20, each die 61 will intercept the conveying surface 58 at the same moment as a respective edge 38 passes through the area of convergence between the rollers 54 and 55 and the surface 58, with the result that a cut 46 is made in the selfsame edge 38 and the portion 47 of the relative flap 33 is bent toward the opposite roller 55 and into the relative socket 63, thereby fashioning the projection 45.
For the purpose of making the bend denoted 48 the surface 60 of the one roller 55 is furnished with two dies 64, each disposed in substantial alignment with a relative socket 63 on a given generator of the roller 55, whereas the surface 59 of the other roller 54 affords two sockets 65 each positioned to admit a matching die 64 and disposed substantially in alignment with a relative cutting die 61 along a given generator of the roller. The two dies 64 are separated by a distance, measured circumferentially around the relative roller 55, substantially equal to the distance separating the two longitudinal edges 38 (effectively the width) of the blank 20, and the radial dimensions of the rollers 55 and 54 are such that when the surfaces 60 and 59 are set in contrarotation at a peripheral velocity equal to the linear velocity V of the blanks 20, each die 64 will intercept the conveying surface 58 at the same moment as a respective edge 38 passes through the area of convergence between the rollers 54 and 55 and the surface 58, with the result that a bend 48 is made in the relative flap 32.
In an alternative embodiment of the machine 50 (not illustrated in the drawings), the blanks 20 might be advanced by the conveyor 51 toward and between the rollers 54 and 55 each with its longitudinal axis 21 disposed parallel to the feed direction D1.
In this instance, the arrangement of the rollers 54 and 55 remains the same as described previously and illustrated in FIG. 2, whilst the surfaces 59 and 60 would be shaped differently inasmuch as the bend 48 in the one flap 32 and the cut 46 in the adjacent flap 33 will be produced in succession, rather than simultaneously, during the passage of the blank 20 through the area of tangential convergence between the rollers 54 and 55 and the conveying surface 58. Accordingly, the two dies 61 of the one roller 54 would be aligned on one and the same generator of the relative cylindrical surface 59, and the two dies 64 of the opposite roller 55 aligned likewise on a single generator of the relative cylindrical surface 60. | Rigid packets of the type with a hinged lid are fashioned from diecut blanks presenting a central longitudinal portion flanked by two lateral portions, each consisting in a series of longitudinally disposed flaps. The method of manufacture involves directing the blanks singly and in succession between a pair of contrarotating rollers with dies shaped and positioned to engage each lateral portion; the dies are designed to modify a pair of adjoining flaps on each side, which ultimately will be bent through a right angle to form an internal layer of the relative flank face of the packet, by producing at least one bend in one flap at an end adjacent to the other flap, and forming a projection on the longer flap which in the finished packet will be breasted permanently in contact with an inner reinforcing frame. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to devices having metallized regions and, in particular, to devices having copper metallized regions.
2. Art Background
A multitude of devices such as multichip modules, printed circuit boards, and hybrid integrated circuits include a patterned region of copper. A clear trend in the manufacture of such devices has been the use of progressively finer patterns, i.e., progressive decrease in metallized line dimension and the spaces between these lines. Presently, typical lines and spaces on printed circuit boards are 150 microns, 50-100 microns on ceramic substrates for multichip modules and at the micron level on silicon devices. The finer the lines and spaces, the greater the density of components and active elements.
The manufacture of devices with copper-containing electrical interconnects such as multichip modules and printed circuit boards is described in compendia such as Thin Film Multichip Modules, G. Messner et al., International Society for Hybrid Microelectronics, Reston, Va. (1992) and Handbook of Printed Circuits, R. Clark, Van Nostrand Reinhold, N.Y. (1985), respectively. For certain substrates such as silicon and ceramics, multilayer metallizations utilizing successive deposition of adhesion-promoting or diffusion barrier metals are required for the overall functioning of the interconnects. Such devices are formed in one approach by depositing a continuous layer or layers of metal, overlying this(ese) metal(s) with a mask such as a patterned polymer mask, and removing by etching the regions of the metal exposed through openings in the mask. A variety of etchants have been employed in this etching procedure. For example, aqueous hydrogen fluoride has been used for the etching of titanium layers, commonly employed as the underlaying bonding layer, while cupric chloride solutions, either containing hydrochloric acid or ammonia, primarily the latter, have been used for etching the thicker copper layers serving as the primary current-carrying component.
Although these solutions have been extensively used, problems still exist in their application as line spacings become smaller. Generally, these etchants rapidly remove material parallel to the substrate at rates comparable to the desired direction normal to the substrate surface. The starting condition is shown in FIG. 1, where 2 denominates the mask material, 3 denominates the metal and 1 denominates the substrate. With the described etchants, the material is removed rapidly towards the substrate and, due to lateral etching, is also etched under the mask material. As a result, configurations such as shown in FIG. 2, are obtained. Clearly, the greater the lateral etching, the larger and less advantageous is the minimum linewidth obtainable. Additionally, as a result of the rapid etch rate, reproducibility is substantially diminished and linewidth control is made more difficult. Thus, in general, it is desirable to produce an etching process which allows greater control with less undercutting.
The problem becomes even more critical when the metal structure to be etched includes a multiplicity of layers of different compositions. For example, metal patterns used in multichip modules to connect components often include an overlying layer of copper, together with an underlying metal layer such as a titanium layer, a palladium-doped titanium layer, or successive palladium and titanium layers. Even if adequate etchants are available for each individual layer, generally, an etchant for one or the other of the metals etches the two at such disparate rates that less than totally desirable results are achieved. Additionally, residues of one or more of the metals often are found in such circumstances. Palladium, interposed between Ti and Cu as metal or Ti-Pd alloy, is not removed by either HF or ammoniacal copper etchants.
For example, in a metallized region on substrate 11, masked by material 14 and having an overlying copper 13 (in FIG. 3) layer and an underlying titanium layer 12, an ammoniacal cupric chloride solution is used to etch the copper, and an aqueous hydrogen fluoride etchant is used to etch the titanium. After the copper is fully cleared using the cupric chloride solution, etching of the titanium with aqueous hydrogen fluoride normally causes substantial undercutting of the titanium layer. Two sources of this undercutting include 1) the immunity of each metal to the other's etchant, thus requiring over-etching to assure complete removal in each step, and 2) formation of a passive oxide left by the copper etchant on the surface of the titanium, requiring an induction period to remove this layer, followed by rapid etch-through and concomitant titanium undercut. As a result, after copper etch, the configuration obtained is shown in FIG. 4, and after the titanium etch, the resulting configuration is shown in FIG. 5. The resulting large undercut in the metal bilayer is certainly not desirable and limits the density of line patterning and utility of the modules.
A few suggestions have been reported for etching metallized regions containing more than one metal layer. For example, as discussed in K. L. James, et al., U.S. Pat. No. 4,345,969, dated Aug. 24, 1982, and M. A. Spak, U.S. Pat. No. 4,220,706, dated Sep. 2, 1980, combinations including strongly oxidizing, concentrated inorganic acids have been employed. Nevertheless, the use of such combinations severely limits substrate and resist composition. It is desirable to have an etchant that allows increased resolution for producing copper lines and that promotes the controlled etching of multilayer metal regions. It would also be environmentally desirable to have an etchant for which recovery of copper and regeneration of used etchant with minimal waste disposal are feasible.
SUMMARY OF THE INVENTION
By using an aqueous cupric chloride solution including an acid such as hydrofluoric acid, and a chloride salt such as potassium chloride, increased resolution for copper etching and reproducible control for the etching of multilayer metal regions such as copper/titanium and copper/palladium/titanium multilayer structures, is possible. This result is particularly surprising since an HF etchant or a cupric chloride etchant used individually, as previously discussed, yields unsatisfactory results.
Thus, through the use of a combined solution, etching rates of copper and titanium are adjusted to be quite similar and controllable, allowing the reproducible formation of multilayer metallized patterns with nearly vertical sidewalls for the combined multimetal structure. Unacceptable residues often associated with multilayer metals such as palladium are not present. Additionally, the etchant solution is easily recycled.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-5 illustrate configurations achieved with single and multiple layer etching, and
FIG. 6 demonstrate configurations and properties achieved with the subject invention.
DETAILED DESCRIPTION
As discussed, an aqueous cupric chloride solution including an acid such as hydrofluoric acid, and chloride salt in addition to the cupric chloride is particularly advantageous for providing fine line copper structures and for etching multilayer copper structures without unacceptable undercut. Copper patterns are formed by a variety of etching techniques as described in compendia such as Clark, supra. The inventive etching process is generally employable in accordance with these techniques. Typically, a layer of the copper material is formed by conventional techniques such as sputtering or electroplating. In multilayer structures, typically a lower layer (lower or underlying, in the context of this invention, refers to a layer closer to the substrate), is first deposited by conventional techniques, and then the above-described overlying layer of copper is formed. To etch the pattern, the layer or layers of material to be etched are covered with an energy sensitive material such as a photoresist, the energy sensitive material is patterned to form an etch mask having the desired pattern, and etching is induced by contact with an etchant.
In such etching procedures, an aqueous solution is employed as the etchant. The etchant is introduced by conventional techniques such as immersing with agitation the substrate with its etch mask in the etchant, by spraying the etchant onto the substrate, or by other means of convective motion. Typically, the layer or layers to be etched are subjected to the etchant for time periods in the range 5 seconds to 10 minutes. Generally, time periods longer than 10 minutes are undesirable because of non-uniformity of results and slow process flow, while time periods shorter than 5 seconds lead variously to incomplete etching, irreproducibility, and excessive undercutting.
The composition of the etching solution should be controlled. The aqueous solution should contain cupric chloride. Concentrations in the range 0.2 to 2M of cupric chloride are generally employed. The rate of copper etching depends on the cupric species concentration, chloride concentration, and acid concentration. The chloride salt (such as NH 4 Cl, NaCl, KCl and LiCl) should be soluble in the etchant mixture and should not chemically react with the etchant constituents. The concentration of chloride salt in the aqueous etchant should be in the range 1 to 5M. Concentrations greater than 5M lead to solubility problems, while concentrations less than 1M yield slowed etching. Typically, chloride salts such as potassium chloride and sodium chloride are used. The mole ratio of chloride salts to cupric chloride should be in the range from 1:1 to 10:1.
The titanium layer is etched by the hydrofluoric acid component which is generally employed at concentrations of 0.5 to 10 weight % HF. The exact composition employed should be adjusted by corresponding adjustment of the relative concentration of the components so that the etch rate of the layers to be etched does not vary by more than a factor of two.
After etching, it is typically desirable to remove any residual presence of etchant by rinsing with water. Although such a rinse is generally employed as a precaution, by the use of the inventive process, residues such as palladium containing residues, are not present after etching and, thus, an advantageous, clean process is achievable.
The following examples are illustrative of the invention.
EXAMPLE 1
Sufficient cupric chloride, potassium chloride, and HF was added to water to make the resulting solution 0.66M in cupric chloride, 1M in potassium chloride, and 2.1M in hydrofluoric acid. A substrate was prepared by depositing, over the entire major surface, a composite region of titanium and palladium having a thickness of 0.11 μm. An overlying copper layer was deposited with a thickness of 2.5 μm. (The substrate was either an alumina ceramic or an alumina ceramic coated with a layer of dielectric polymer.) A conventional photoresist was deposited onto the copper, exposed in a test pattern, and developed by conventional techniques. Etching was then initiated by spraying the delineated substrate with the etching solution for 35 seconds using an array of nozzles with the substrate held in a vertical position. The resist material was then removed using a standard resist stripper and the resulting pattern inspected.
The copper undercut was calculated by subtracting the measured linewidth from the linewidth delineated in the photoresist, and averaged 7.4 μm, plus or minus 1.8 μm over 69 measurements. (Linewidth was measured using optical microscopy.) This undercut was approximately equivalent to that generally observed for conventional processes.
The titanium undercut was also measured by first removing the overlying copper layer with an alkaline copper etch which did not attack the underlying titanium layer. The undercut in the exposed titanium layer, was calculated by subtracting the measured width of the titanium line from the previous measurement width of the copper line, and was essentially zero, i.e., -0.6 μm, plus or minus 0.8 μm averaged over 69 measurements. This undercut is extremely good as illustrated in FIG. 6, compared to the 5.8 μm, plus or minus 3.4 μm, observed with the same process using sequential etches of ammoniacal cupric chloride for the copper and aqueous HF for the titanium. Additionally, no residues were visible nor was any leakage current detectable by a gigaohmmeter. | The linewidth in patterns produced by etching copper layers is more easily maintained using a specific etching medium. In particular, this medium includes aqueous hydrofluoric acid, copper chloride, and an additional chloride salt. The etching medium is also particularly useful for bilayer metal constructions such as the copper/titanium structure found in many multichip modules. | 7 |
This is a division of application Ser. No. 505,565, filed June 17, 1983.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of metal stampers for use in the replication of optically-readable information bearing members. More specifically, the invention is involved in the replication of optically-readable information bearing members by means of an injection molding process utilizing a stamper having a conformal layer of chromium electrolytically deposited over the encoded surface of an existing optically-readable information bearing nickel stamper.
While the improved stamper according to the present invention and the method for making such improved stamper can be used in connection with the production of plastic information bearing surfaces in which micron-sized surface discontinuities are formed in any geometrical configuration, for ease of understanding the devices of the prior art and the invention will be explained using a disc-shaped information bearing member as exemplary. Since the improvement over prior art methods involves the characteristics of the interface between the stamper and the plastic, it will be appreciated that the concepts of the invention broadly apply to the injection molding of information bearing plastic articles of virtually any geometrical shape.
2. Description of the Prior Art
Replication of optically-readable information bearing members by an injection molding process in plastic is well known in the art. Such a process involves liquid plastic injected into a disc-shaped mold and pressed between an encoded stamper surface of nickel (bearing audio, video, and/or digital information) and a rigid backplate. The liquid plastic is allowed to harden and to cool, and is then subsequently "released" from the encoded nickel surface.
Typically, the prior art employs the use of nickel as the stamper material because of its innate structural qualities: a sufficient hardness to bear the fatigue in the mold and release phases of the injection molding process; the considerable ease with which nickel metal can be electrolytically deposited in large amounts; the relatively low cost for the material; and the wide tolerable range of process controls and parameters.
A process for producing a stamper for video-disc purposes is the subject of U.S. Pat. No. 4,211,617, issued July 8, 1980 in the name of Csaba K. Hunyar, assigned to the assignee of the present invention. Hunyar proposes a multi-layer stamper comprised of copper and nickel. The metal layer is applied by vapor bombardment, vapor deposition, or deposition from an electroless plating solution. A "matrix" surface containing the originally recorded information is first silver-plated with an electroless process similar to that used for producing mirror surfaces. The silver film is deposited only to a thickness sufficient to support electroconductivity, typically from about 0.01 to about 2 mils, so that the next electroplating step can be undertaken. The nickel and copper conforming layers are then deposited by an electroplating process to a thickness of from about 3 to 20 mils total thickness, the final layer against which the plastic is molded being the nickel layer.
Upon visual inspection, replicas prepared from a nickel stamper may exhibit glowing orange patches when observed in transmitted light which have the appearance of "surface stains" and which are generally attributed to a surface distortion phenomenon referred to as the "plowing effect" that occurs during the injection molding process. The term "plowing" was coined after observing microphotographs of the surface discontinuities of the replicas and noting that the "bumps" defining the information track thereon were cut away as if by plowing or as if the "bumps" had collided with a sharp object. Subjecting discs prepared from a nickel stamper to . various unique tests (to be described in greater detail hereinafter) indicates a direct correlation between the visibly observable "plowing effect" and disc information reproduction quality.
By monitoring various electronic signals as a laboratory disc test player is operated in modified play and scan modes, it is possible to create maps bearing information related to the extent and intensity of surface defects. Such maps plot defective areas with black dots varying in intensity, determined by the magnitude of the defect. Although such "electronic" testing correlates generally with visual inspection, obviously the "electronic" test results are more representative of actual surface defects. In this description plots or maps which are produced by displaying results of "electronic" testing will be termed "electronic interpretations" as contrasted to, for example, visual observations. Electronic interpretations produced by inspecting replicas prepared in a nickel stamper, exhibit distinct darkened regions in and around the "plowed" areas as confirmed by the above-noted visual inspection. These darkened areas correlate precisely with corresponding regions on the disc that exhibit increased audio noise, increased audio crackle and increased numbers of FM drop-outs. The "audio noise" analysis is performed by analyzing the recovered audio signal in a scan mode of the test disc player; "audio crackle" is an analysis evaluating the audio signal recovered during standard play mode; and "FM drop-outs" involve a measurement of the number of times and position on the disc that the recovered FM signal is interrupted.
Visual and electronic inspection of replicas formed against nickel stampers also reveal the presence of an "orange peel" effect within part of the most strongly "stained" areas. The term "orange peel" is descriptive of the appearance of the outer surface of an information storage disc through which a reading light beam must pass before reaching an information-containing surface. The rough-looking, but uniform, surface defect has the visual appearance of the skin surface of an orange. "Orange peel" causes changes in the refraction coefficient from point to point on the disc surface and results in greater loss of tracking. The possibility has been suggested that audio crackle might arise out of an interaction between the "plowing" and the "orange peel". On close inspection, the "orange peel" effect is seen to be slightly inside the radius of the "stained" or "plowed" region at which audio crackle and FM dropouts are more prominent.
Thus, "orange peel" and "plowing" are deleterious by-products of the replication process for producing optically-readable information bearing members formed with nickel stampers. Accordingly, there is a need in the art for improved audio-visual quality of optically readable information bearing members, and the present invention fills this need in the reduction or elimination of "plowing" and "orange peel" through cleaner release at the interface of the master stamper and the stamped article.
SUMMARY OF THE INVENTION
The present invention substantially overcomes all of the deficiencies of the prior art noted above by providing an improved stamper resulting in increased signal quality and increased replication yield of optically-readable bearing members, through the elimination of deleterious surface defects resulting from the injection molding replication process.
More specifically, the present invention provides a method and means for improving the "release" characteristics attributed to the stamper surface in the injection molding process, resulting in increased recovered signal quality and increased stamper yield through the reduction of stamper related defects.
In simplest terms, the invention involves an improved stamper surface comprised of a thin layer of chromium metal deposited over an existing nickel stamper. Such a surface insures a cleaner release at the interface of the master stamper and stamped article.
In a preferred embodiment, the chromium surfaced stamper is an encoded disc-shaped surface which bears audio/video/digital information onto which liquid plastic is formed, hardened, cooled, and released during the injection molding process. Chromium, by its innate structural characteristics, provides a much harder and smoother stamper surface than that of nickel used in the prior art, resulting in the elimination of the particular pit or bump deformation known as the "plowing effect" which is believed to be caused by the differential shrinkage of the hardening plastic as it is formed against the encoded stamper surface.
Prior to any intense study to find a cure for the "plowing effect" which, before the present invention was a defect known to have a negative effect on playability, it was decided to use a chrome surfaced stamper solely for the purposes of extending the life of each stamper because of the increased hardness of chromium over nickel. It was also conceived that such improved hardness may permit the production of a great number of submasters made from the same original master when considering large quantities of replicas having the same program material.
It was after producing replicas from the first hardened, i.e. chrome plated, nickel stamper that the surprising additional benefits in the improvement of quality of signal recovery was noticed. Comparative testing led to a correlation between signal improvement and lack of "plowed" regions on the replicas. More surprising was the observation that the actual signal recovered upon playback of the replica made against a chrome plated stamper was better than that recovered from a replica made against the original nickel stamper before plating, in spite of the fact that microphotographs showed a definite loss of definition of the surface discontinuities defining the information content. Although contrary to what would be expected, it was conjectured that the type of loss of definition that the thin chrome coating produced, especially in the elimination of sharp edges and abrupt surface changes, permitted more uniform shrinkage of the hardening plastic and avoided plowing of the edge of the surface discontinuities during hardening and releasing of the hardened replica from the stamper surface. Further testing showed that improved yield could be obtained from a chrome plated stamper than with the same stamper before chrome plating. That is, surprisingly, chrome plating could render usable an otherwise "defective" stamper, i.e. a stamper which produced defective replicas.
In this connection, it would appear that in an effort to create exactly defined bumps or pits, the artisan unknowingly caused "plowing" to be more prominent resulting in lower yields. On the other hand, adjusting process controls to purposely reduce definition in the original nickel stamper causes other problems, such as incomplete or inconsistent formation of bumps or pits, decreased signal-to-noise ratio, and inconsistent duty cycle of the recorded information. The chrome plating of a well defined nickel stamper information bearing surface, however, produces optimum results for all of these parameters. In such a case, the "exactly defined" bumps or pits of the original nickel stamper are uniquely modified by the chrome plating process to retain the definition needed for consistent duty cycle and good signal-to-noise figures while at the same time avoiding the problems associated with the "plowing effect".
Electronic dot maps produced from the aforementioned proccdure, show no indication of the plowing effect with the use of the chromium surfaced stamper as was prominent in the use of prior art nickel stampers. The plowing effect of nickel stampers has been attributed to the hindering of a uniform flow of liquid plastic over the nickel stamper surface and the generating of an undesirable adhesive effect between the stamper and the stamped article. Replicas produced by chromium surfaced stampers exhibit a substantial decrease of audio noise, audio crackle, FM drop-out, and show little or no signs of "orange peel", thereby resulting in an increased audio/visual/digital information quality of the recovered signal.
In addition to plowing reduction, chrome plated stampers offer increased acid (finger print) resistance and possess the ability to be easily cleaned when soiled as compared to nickel surfaced stampers.
Chromium surfaced stampers produce a higher replica yield than that attributed to nickel stampers, not only in the number of playable discs which result, but also in the reduction of wear and surface defects attributed to the harder chromium surface subjected to repeated replication of stamped articles under high pressure and heat. The present invention thus provides an increased stamper life as compared to the prior art as a result of the chromium outer surface of the stamper being of a harder and thus more durable metal than nickel.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exaggerated and magnified view of the information bearing surface of an optically-readable disc or stamper;
FIG. 2 is a photograph of the information track formed on a nickel stamper with magnification at 40 kX;
FIG. 3 is a photograph of the information track formed on a chrome plated nickel stamper with magnification at 40 kX;
FIG. 4 is an enlarged drawing of the thin layer of chromium metal deposited over an existing nickel stamper;
FIGS. 5A and 5B show the electronic interpretations of recovered audio noise from a replica tested at scan speed and produced from a nickel stamper;
FIGS. 6A and 6B show the electronic interpretations of recovered audio noise from a replica tested at scan speed produced from a chromium surfaced stamper;
FIGS. 7A and 7B show the electronic interpretations of recovered audio crackle from a replica tested at normal play speed and produced from a nickel stamper;
FIGS. 8A and 8B show the electronic interpretations of recovered audio crackle of a replica tested at normal play speed and produced from a chrome surfaced stamper;
FIGS. 9A and 9B show the electronic interpretations of FM drop-outs of a replica produced from a nickel stamper;
FIGS. 10A and 10B show the electronic interpretations of FM drop-outs of a replica produced from a chrome surfaced stamper;
FIG. 11 is the electronic interpretation of "orange peel" of a replica produced from a nickel stamper;
FIG. 12 is the electronic interpretation of "orange peel" of a replica produced from a chrome surfaced stamper.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The process by which prior art stampers were produced begins with a 1/4 inch disc-shaped plate of glass onto which a thin layer of photoresist is applied. A laser beam then encodes information onto the layer of photoresist by selectively exposing the photoresist, and after developing, the layer exhibits recorded information in the form of microscopic pits. A minute layer of nickel a few Angstroms thick is vacuum deposited onto the encoded surface. Additional nickel is then electrolytically deposited over the vacuum deposited nickel layer to a sufficient thickness to bear the pressures encountered in the injection molding process. The glass plate is separated from the nickel, exposing the encoded nickel surface which appears as tracks of microscopic bumps approximately 0.6 microns wide and approximately 0.6 to 2 microns in length projecting from a planar base surface. This is schematically illustrated in the exaggerated and magnified drawing of FIG. 1 in which a disc 2 has a planar base surface 4 from which projects a series of bumps 6 defining circular tracks.
A microphotograph of a small portion of the surface of a nickel stamper is seen in FIG. 2, the view being taken along a radius of the disc close to the inner radius of the disc. It should be noted that, while the following discussion will be concerned with optically encoded discs and the replication thereof by an injection molding process using stampers with bumps projecting out of a planar surface, the invention is applicable to other geometrical forms for the information bearing surface, with the surface discontinuities in the form of pits projecting inwardly from the planar surface. The microphotograph of FIG. 2, of course, illustrates the "bump" configuration and shows the bumps with well defined and sharp edges, as well as a relatively flat upper surface. The sharp edges and abrupt surface changes referred to earlier can be observed in FIG. 2, and it is these physical characteristics of the pits or bumps which seem to contribute to the plowing phenomenon, and the sharper the edges the greater the influence on the extent of plowing in the replicas when they are separated from the stamper.
The introduction of chrome alleviates the problems associated with sharp edged pits or bumps on the nickel stamper. Moreover, the chrome plated stamper avoids the contribution to the "plowing effect" attributed to the surface characteristics of the nickel stamper hindering uniform flow and generating an unnecessary adhesive effect of the mold plastic on the stamper. The poor throwing power, i.e., nonuniform metal distribution, of the chrome plating bath allows a rounding off of the bumps. This reduces the sharp edges on the bumps and, in turn, reduce the amount of plowing. The smoother surface of the chrome also allows uniform flow of the mold plastic on the stamper, and the harder chrome surface is, of course, more durable than the nickel surface.
FIG. 3 shows the same stamper as in FIG. 2 after chrome plating. While the planar surface between bumps appears to be grainer, the fact that the plated surface is of chromium material accounts for the "smoother" surface characteristic.
To carry out the chrome plating process, the already-prepared nickel stamper may be mounted to a cathode fixture (not shown) by any suitable fastening means. Anode bars, which may be a plurality of cylindrical bars of lead-antimony alloy (93%-7%), and the cathode fixture should be immersed with adequate coverage of these members by the chrome plating solution. The plating bath consists of an aqueous solution of chromium as CrO 3 and sulfate as H 2 SO 4 . The immersed stamper should be separated from the bottom of the tank and the solution surface by approximately five inches to have a uniform primary current distribution.
The sulfate concentration is adjusted until iridescent rings disappear and a faint bluish color appears on the stamper.
The nickel stamper is cleaned of any oil and any stripable protective coating residues from the mastering process by using an appropriate degreaser. The stamper is then placed in an alkaline cleaner and cathodically cleaned, rinsed, acid dipped, rinsed again, and then tightly secured so the stamper fixture. The stamper fixture is then immersed into the chrome solution attached securely to the cathode bar. Plating is then initiated for a given time, after which the stamper is removed from its fixture, rinsed thoroughly, and dried, preferrably in a suitable vapor degreaser.
Various combinations of solution concentrations, temperatures, and current densities were tried starting with the suggested quantities of CrO 3 and SO 4 (from H 2 SO 4 ). The best results were obtained with a CrO 3 to SO 4 ratio of 76 versus 100 according to recommended industrial specification. Temperature ranges were tried between 30° C. and 53° C., and concentration levels for the plating solution were found to be best when the concentration of CrO 3 was in the range of 4.0 to 35 grams per liter (g/L) and the concentration of H 2 SO 4 was in the range of 0.05 to 0.5 g/L.
After evaluating several samples made with different combinations of process parameters, optimum process specifications for the flash plating of chromium on nickel stampers was developed. The chrome plating bath appears to be optimized with a composition of 33.5 ounces per gallon (oz/gal) or (4.44 gm/liter) of CrO 3 and 0.44 oz/gal (0.058 gm/liter) of SO 4 , the CrO 3 -to-SO 4 ratio being optimized at 76. The plating temperature was not critical, and optimum plating could be obtained in the temperature range of between 40° C. and 50° C. Using stampers having an outside diameter of 30 centimeters and an inside diameter of the opening of 8.9 centimeters, the area to be plated is calculated to be approximately 644 cm 2 . With an optimum current density of 0.3-0.5 Amps/cm 2 , the current required for plating the full surface of the stamper ranges from 195 to 325 Amps. Consistently good results were obtained with a full bath current of 210 Amps applied for 25 seconds.
FIG. 4 shows a partial cross-section of a stamper made in accordance with the present invention. The stamper 12 is comprised of a nickel stamper base 14 having a thickness in the range of 2 to 30 mils and is typically about 15 to withstand the pressure of injection molding. For illustrative purposes, the upper planar surface 16 of the stamper base 14 has projections 18, herein referred to as "bumps" which are on the order of 0.15 microns in height. The vacuum deposited nickel layer 20 is only a few Angstroms thick, recalling that the nickel vacuum deposited layer was necessary to support conductivity for the glass/photoresist master matrix from which the nickel stamper base 14 was produced.
In a test environment, set up to verify the signal recovery improvement using chrome plated stampers, a total of nineteen replicas were provided for examination. The replicas were all made from a transparent and impact modified polymethylmethacrylate plastic. Eleven were produced from a nickel stamper, and eight were produced from a chrome plated stamper. For comparative purposes, a selected group of the replicas were produced from a chrome plated stamper and others were produced from the same nickel stamper prior to chrome plating. The stampers used in the test were particularly chosen for their known propensity to produce plowing in the replicas.
When placed on a strong light table and viewed in a darkened room, 100% of the "pre-chromed" and "non-chromed" replicas exhibited glowing red patches identifiable as plowing. The patches were particularly prominent and extensive on the replicas made from the nickel stamper prior to chroming. The stronger patches also appeared slightly milky or opalescent when viewed in reflected light. By contrast, none of the replicas made from the same stamper after chrome plating showed any patches on the light table.
As confirmation that the elimination of plowing would render the replicas made therefrom more playable, an "audio noise at scan speed" test was devised. By operating a standard video disc player, such as the Discovision Associates PR-7820 player, in a modified playing mode, it was possible to create dot maps showing a distribution of dot patterns related to the extent and intensity of plowing surface stains. Various electronic signals produced by the player when operating in a special scan mode were monitored. The electronic interpretations shown in FIGS. 5A-B and 6A-B were made by running the left audio output, with squelch and dropout-compensation defeated, through a 100 KHz high-pass filter, and counting the fluctuations at the output of the player greater than ±3 millivolts. The player was operated in a slow forward scan mode. The disc was turned at normal speed, i.e. 1800 RPM, while the translation of the read beam across the disc required only about 2 minutes for a complete pass from the inner to the outer radius. The maps shown in the figures are all oriented in the same direction for comparative purposes. The truncation of the edges of the disc representations in the figures was due to the fact that the image scale was too large for the monitor used.
FIGS. 6A and 6B show the "audio noise test at scan speed" results using replicas made from the same stamper as those used to produce the replicas of FIGS. 5A and 5B after chrome plating. The rapid scan tests clearly corroborate the visual impression that the replicas produced after chrome plating exhibit far less stain than those produced before plating. Interestingly, the complicated stain pattern on the pre-chrome replica of FIG. 5A is remarkably consistent from disc-to-disc, and the areas of less-than-average stain around the major defects appear to be somewhat predictable as well. The patterns on the prechrome and non-chrome discs, however, appear to be somewhat variable, with some features intensifying and others diminishing, as successive replicas were made. On the other hand, by observing other "control" replicas made from a different stamper than those shown in FIG. 5, the patterns on the replicas produced by such different stamper had no obvious relationship to the pattern of FIG. 5. That is, using the same stamper, the plowing effect appeared to have a consistent pattern disc-to-disc, but no related pattern characteristics were noted in replicas made on different stampers. The example of FIG. 5 thus could not be termed "typical" insofar as the pattern of the defect is concerned, but is typical of the extent and kind of distribution that the plowing effect has in observing other replicas (not shown) submitted for evaluation. In any event, the improvement in the disc quality seen in FIGS. 6A and B is illustrative and characteristic of the use of chrome plated stampers.
Because only a finite number of dots are needed to produced a solid black area in the display, the maps of FIGS. 5A and 6A cannot always be depended upon to give an entirely accurate impression of the relative strengths in the different regions of the defect. Accordingly, a graphical representation of the plowing defect was created using the output from the modified disc player, the results shown in FIGS. 5B and 6B. Information for the graphs was gathered by counting the number of audio noise spikes occuring in each 0.5 second interval as the disc was scanned. The count per 0.5 seconds is shown on the ordinate axis of each graph, while the absissa axis shows radius of the disc in millimeters. It has been empirically determined that the best results for the graph plots of FIGS. 5B and 6B are obtained by using the output from the audio FM demodulater within the player unit. At this point in the electronics, the spikes are most easily separated from the program material, and a good representation of the plowing stain pattern can be extracted by passing this signal through a 10-50 KHz filter and counting the spikes exceeding ±0.45 volts.
A remarkable improvement in audio quality, i.e. lack of noise spikes, is evident from the comparison of the results of FIGS. 5B and 6B. For convenience, since the counts per 0.5 seconds in FIG. 5B were off the scale at the most dense region, a divide-by-10 plot is shown to indicate the peak noise spike count which, for this test sample, is about three thousand spikes per 0.5 seconds.
For comparative analysis, a second type of audio noise test was developed, referred to herein as the audio crackle test which is performed in the normal play mode of the player. The best results for the audio crackle test were found to be derived from the normal or final output of the player as opposed to the output of the FM demodulator which appeared to be best for certain scan speed analysis shown in FIGS. 5 and 6. FIGS. 7A-B and 8A-B thus show comparative test results using the audio crackle test at normal play speeds, FIGS. 7A and 8A showing the dot map display, while FIGS. 7B and 8B show the graphical representation which is similar to that of the corresponding plots shown in FIGS. 5B and 6B, with the exception that the number of audio crackles detected and displayed along the ordinate axis of FIGS. 7B and 8B are in terms of crackles per 100 seconds. Since the audio output of the player is used for audio crackle tests, in order to produce optimum results, the output of the player is passed through a 100 KHz high-pass filter, and residual spikes were observed which exceed ±3 mV.
As with the audio noise test at scan speeds, the audio crackle test in the normal play mode shows similar test results, and again the plot of FIG. 7B shows a divide-by-10 version of the results for convenience.
The audio noise and audio crackle tests indicate that in the area of the major cresent stain on the pre-chrome replica, about 20 to 30 times as many defects are counted per second as on the replica made from the same stamper after chrome plating. Observing that the counts accumulated for the particular test sample were strongly distributed on only about one-half of the disc in angle, it is apparent that the local defect density is even higher, i.e. at least 40 times that on the replica from the plated stamper.
The maps shown in FIGS. 5A and 7A indicate that only the strongest of the stains on the pre-chrome replica is associated with measurable crackle. Further, such crackles appear to be spread more or less uniformly over the area of the stain. The peak rate of crackle count is about 90 counts per second.
As a final comparative test, the discs were subjected to an analysis of FM dropouts, the results of which are shown in FIGS. 9A-B and 10A-B. FM dropouts are easily detected, since the player itself has been designed with a dropout compensation network to sense when dropouts occur and operates to substitute signal information in place of the areas of dropout to make the defect less noticeable. It is a simple matter to feed the output of the FM dropout detector to a threshold device such that when dropouts occur, the threshold level is exceeded, and a count pulse is outputted. For the evaluation of the test samples shown in the figures, a dropout is declared whenever no new zero-crossing of the FM signal recovered from the disc is detected for mcre than 100 nsec.
FM dropouts are typically more prevalent than indications of defective areas causing audio noise or audio crackle. Accordingly, although dropouts are observed in the normal play mode of the player, only a sampling of the dropout pulses developed by the player are used for defect evaluation. Alternatively, samples may be made in a mode in which the player is instructed to recover information from every second or third track, i.e. the read beam is jumped forward to skip a given number of tracks. The reason for this modified procedure is that the dropout rate on many replicas is so high that if all of the dropouts were plotted, a completely black and uninterpretable display would be obtained. The maps and graphs of FIGS. 9A-B and 10A-B show only one dropout out of every eight detected.
The worst dropout problems, with dropouts approaching 8,000 per second are found on the prechrome replica. This translates, using a frame rate of 30 frames per second, to approximately 260 dropouts per frame. The problem is mainly localized in the same strongly stained and crackly cresent that has been observed previously. The background rate over the rest of the disc, amounting to about 15 counts per frame, is also rather high.
As was observed with the crackles, the replicas produced by the chrome plated stamper has greatly supressed dropout rate in the original problem area, but at the same time the distribution is somewhat more spread out so that the bordering areas of the originally noted defective area are actually noisier than they were on the original stamper. Although less severe than the original problem, the peak rate of about 50 dropouts per frame (1,600 per second) is on the borderline of being acceptable. However, as previously mentioned, the stamper used in this analysis was chosen for its large and above-normal intensity of defected area, and stampers having typically, less intense and wider distributed stained regions show that, when considering the average dropout rate, the "chrome" replica is far better than the "pre-chrome" replica.
Visual inspection of the replicas submitted for evaluation revealed the presense of orange peel within part of the most strongly stained area on the replicas made from the pre-chrome stamper, as well as peripheral areas not contributing to the plowing effect. Electronically, the magnitude of the orange peel can be evaluated by measuring the error signal on the tracking servo board of the player. The orange peel on the replicas tested prove to be not overly severe (tracking errors of less than ±2 volts). Dot maps were developed using replicas before and after chrome plating, the dot pattern being developed by sensing the tracking error signal. Points at which the tracking error exceeded ±1 volt were printed on the display while running the discs at the normal constant rotational speed of 1800 RPM. The results are shown in FIGS. 11 and 12, FIG. 11 being the pre-chrome replica and FIG. 12 showing the lack of orange peel in the replica produced by the same stamper after chrome plating. Thus, it can be concluded that the orange peel effect is reduced and therefore the trackability improved after chrome plating the nickel stamper.
In summary, examination of the replicas provided for analysis comprising examples made from a problem stamper before and after chrome plating, revealed that the chrome plating resulted in a dramatic visual improvement in the amount of plowing stain. The visual improvement can be confirmed electronically by plotting and counting high-frequency audio noise with the player operating in the slow scan forward mode. The original problem stamper produced replicas which exhibited intense dropouts and audio crackle in one of the "plowed" areas. "Orange peel" was observed nearby, but not identically coincident with the main problem area. The peak rates of both crackle and dropouts were much reduced by the chrome plating process, the crackle by a factor of about 27, and the dropouts by a factor of about 5. Around the former peak area (of the nickel stamper replica), the crackle and dropout rates from the chrome-plated stamper were enhanced over what they had been before plating. Total dropouts, however, are not reduced by a large factor, but are more evenly distributed over the surface of the replica. Total crackles are improved by a factor of about seven.
While the invention has been particularly shown and described with reference to the preferred embodiment thereof, it will be understood by those skilled in the art that changes in form and details may be made therein without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited except as by the appended claims. | An improved stamper and method involved in the replication of optically-readable information bearing members by means of an injection molding process utilizing a stamper having a conformal layer of chromium electrolytically deposited over the encoded surface of an existing optically-readable information bearing nickel stamper. Nickel stampers produce replicas having structural and optical defects affecting playability of the replica. The present invention provides improvement in the reduction or elimination of "plowing" and "orange peel" defects through cleaner release at the interface of the master stamper and the stamped article. The invention involves an improved stamper surface comprised of a thin layer of chromium metal deposited over an existing nickel stamper. Such a surface insures a cleaner release at the interface of the master stamper and stamped article. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
The present invention relates generally to methods and apparatus for attaching a sensor to a tubing string for deployment within a wellbore. More specifically, the present invention relates to methods and apparatus for attaching a sensor to a tubing string for deployment within a highly deviated wellbore.
During the production of hydrocarbons from an underground reservoir or formation, it is important to determine the development and behavior of the reservoir and to foresee changes which will affect the reservoir. Methods and apparatus for determining and measuring downhole parameters for forecasting the behavior of the reservoir are well known in the art.
A standard method and apparatus includes placing one or more sensors downhole adjacent the reservoir and recording seismic signals generated from a source often located at the surface. Hydrophones, geophones, and accelerometers are three types of sensors used for recording such seismic signals. Hydrophones respond to pressure changes in a fluid excited by seismic waves, and consequently must be in contact with the fluid to function. Seismic waves are waves of elastic energy, approximately in the range of 1 to 100 Hz, having both a compressional and a shear component, where the compressional component, or P-wave, oscillates in a direction parallel to propagation of the wave, and the shear component, or S-wave, oscillates in a direction perpendicular to the propagation of the wave.
Hydrophones are non-directional and respond only to the compressional component of the seismic wave. They can be used to indirectly measure the shear wave component when the shear component is converted to a compressional wave (e.g. at formation interfaces or at the wellbore-formation interface). Geophones measure both compressional and shear waves directly They include particle velocity detectors and typically provide three-component velocity measurement. Accelerometers also directly measure both compressional and shear waves, but instead of detecting particle velocities, accelerometers detect accelerations, and hence have higher sensitivities at higher frequencies. Accelerometers are also available having three-component acceleration measurements. Both geophones and accelerometers can be used to determine the direction of arrival of the transmitted waves.
Other sensors are available that enable various parameters to be measured, especially acoustic noise, natural radioactivity, temperature, pressure, etc. The sensors may be positioned inside the production tubing for carrying out localized measurements of the nearby annulus or for monitoring fluid flowing through the production tubing. While the location within the wellbore of some of these sensors is not critical, in the case of geophones and accelerometers, the sensors must be mechanically coupled to the formation in order to conduct the desired measurement.
One method of coupling a sensor to the formation is by providing the wireline sonde with a mechanical arm which can be extended against the wall of the casing. The arm may be extended by mechanical means, fluid pressure, or electrical actuation. When extended, the arm presses the sensor against the opposite wall of the casing with a force sufficient to prevent relative motion of the sensor with respect to the casing. As a rule of thumb, the force applied by the arm should be at least five times the weight of the sensor, and it is not uncommon for sensors to weigh 30 lbs. or more.
Another mechanism for coupling a sensor to a formation involves the use of springs to force the sensor against the wall of the casing. The sensor is maintained in a retracted position while the tubing string is run into the wellbore. When the tubing string has reached its deployment location, the springs are released and force the sensor against the casing. As in those designs employing arms, the springs are designed to provide a certain force to push the sensor onto the casing. When operating in highly deviated well sections, including near horizontal and horizontal sections, both spring and arm systems have faced challenges. In contrast to a normal vertical wellbore, where the string is likely to be somewhat centered, in these highly deviated sections the tubing string is likely to rest against the casing with some or all of the weight of the string bearing against the casing wall.
Although most spring and arm systems are designed to actuate with a force greater than the weight of the sensor, they may not have enough force to push the string away from the casing, when the sensor is between the casing and the tubing, or sufficient reach to push the sensor against the far wall of the casing, when the tubing is directly against the casing. If the system fails to fully actuate, the sensor may not be maintained in the desired, stable relationship with the wellbore, making data acquisition conditions less than ideal.
Thus, there remains a need in the art for methods and apparatus to deploy sensors into highly deviated sections of a wellbore. Therefore, the embodiments of the present invention are directed to methods and apparatus, for attaching a sensor to a tubing string for deployment in a highly deviated wellbore section, that seek to overcome these and other limitations of the prior art.
SUMMARY OF THE PREFERRED EMBODIMENTS
Accordingly, there is provided herein methods and apparatus for attaching a sensor to a tubing string for installation into a highly deviated wellbore. The preferred embodiments of the present invention are characterized by an apparatus for securely affixing a sensor to a tubing string, wherein the apparatus also provides a sufficient coupling to the casing of the wellbore. The embodiments of the present invention act to provide stable, reliable coupling between a sensor and the casing of a highly deviated wellbore. In this context a stable, reliable coupling is achieved when a sensor is maintained in a position to the wellbore where no relative motion occurs between the sensor and the wellbore during data acquisition.
In preferred embodiments, the invention includes at least the following embodiments. One embodiment of an apparatus for collecting data from a wellbore includes a sensor, a tubing string, and a connector that fixes the sensor to the tubing so that there is no relative motion between the sensor and the tubing. One such connector includes a first clamping portion and a second clamping portion adapted to form a clamp assembly around a tubing string. The first clamping portion encloses the sensor and attaches around the tubing string to the second clamping portion. The outside surface of both first and second portions may have a plurality of contact members connected thereto for interfacing with the wellbore.
The first clamping portion also provides access to connect a sensor to adjacent sensors in a sensor array. In alternative embodiments, either the first or second portion inside diameter may have one or more gripping dogs to ensure the attachment to the tubing string. The clamp assembly may also have one or more bypass grooves to allow for tubing and/or cabling from adjacent instrumentation packages to bypass the clamping assembly.
The present invention may also be embodied as a method for disposing a sensor in a highly deviated or horizontal wellbore. A sensor is placed inside a first clamping portion that is combined with a second clamping portion and compressed against a tubing string using a predetermined force. Once the predetermined force is reached, attachment members are installed attaching the first portion to the second portion. Sensor and clamping assembly is then lowered into the wellbore where, in a highly deviated or horizontal section, the tubing and clamp assembly will come to rest on one side of the casing.
When disposed in a highly deviated or horizontal wellbore, the mass of the tubing string will force the clamp assembly to the lowermost portion of the casing. The clamp assembly will come to rest on the inside of the casing, preferably contacting in at least two points, and a coupling will be formed between the sensor and the casing across the clamp assembly and the contact members.
Thus, the present invention comprises a combination of features and advantages that enable sensors to be reliably deployed in a highly deviated or horizontal wellbore. These and various other characteristics and advantages of the present invention will be readily apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments of the invention and by referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more detailed understanding of the preferred embodiments, reference is made to the accompanying Figures, wherein:
FIG. 1 is a perspective view of a clamp assembly;
FIG. 2 is a sectional view of the clamping assembly of FIG. 1 ;
FIGS. 3 a - 3 e are partial sectional views of a clamp assemblies disposed within a wellbore.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the description that follows, like parts are marked throughout the specification and drawings with the same reference numerals, respectively. The drawing figures are not necessarily to scale. Certain features of the invention may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in the interest of clarity and conciseness.
The preferred embodiments of the present invention relate to methods and apparatus for attaching a sensor to a tubing string for deployment in a highly deviated section of a cased wellbore such that the sensor is maintained in a stable, reliable relationship with the well casing. The present invention is susceptible to embodiments of different forms. There are shown in the drawings, and herein will be described in detail, specific embodiments of the present invention with the understanding that the present disclosure is to be considered an exemplification of the principles of the invention, and is not intended to limit the invention to that illustrated and described herein.
Referring now to FIG. 1 , sensor clamp assembly 100 can be seen installed on tubing string 110 . Assembly 100 includes a first clamping portion 300 and a second clamping portion 400 disposed around tubing 110 . Assembly 100 also includes a plurality of contact members 120 which are disposed on the outside surface of both first portion 300 and second portion 400 . First clamping portion 300 is connected to second clamping portion 400 by way of a plurality of attachment members (not shown), such as screws or bolts, disposed within a plurality of attachment holes 320 , 420 in each portion, best shown in FIG. 2 . First portion 300 also preferably has a bypass groove 330 in which may be disposed a cable 140 . Each end of first portion 300 also preferably has an access hole 350 to accommodate interconnection between adjacent sensor assemblies.
Referring now to FIG. 2 , assembly 100 , as installed on tubing 110 , is shown in cross-section. First clamping portion 300 includes sensor cavity 310 , attachment holes 320 , bypass grooves 330 , and inside surface 340 . Second clamping portion 400 includes recesses 410 , attachment holes 420 , and inside surface 440 . Assembly 100 further comprises contact members 120 , sensor 130 , cable 140 , dogs 150 , and dog attachment members 160 .
First clamping portion 300 has an inside surface 340 that is curved so as to conform to the outer surface of tubing 110 . Portion 300 also includes sensor cavity 310 which is adapted to receive a sensor 130 and maintain sensor 130 in stable contact with tubing 110 . Either end of cavity 310 has access holes 350 (as shown in FIG. 1 ) that allow sensor 130 to be connected to adjacent sensors in an array.
The outer surface of first portion 300 has one or more lengthwise bypass grooves 330 that are sized to accommodate cable 140 as it extends past assembly 100 . Grooves 330 are preferably adapted to receive a flat-pack, or other low profile, cable but may be adapted to receive any cable or tubing that may bypass assembly 100 . First portion 300 also has a plurality of contact members 120 attached to the outer surface. Contact members are preferably constructed of hardened metallic materials welded, or otherwise attached, in place. First portion 300 also includes a plurality of attachment holes 320 corresponding to attachment holes 420 in second portion 400 .
Second clamping portion 400 has an inside surface 440 that is curved so as to conform to the outer surface of tubing 110 . Inside surface 440 may have one or more recesses 410 adapted to receive dogs 150 that attach to lower portion 400 by way of dog attachment members 160 . Alternatively dogs 150 may be welded or brazed to inside surface 440 . Dogs 150 are preferably hardened metal inserts having a raised profile so as to prevent movement of second portion 400 relative to tubing 110 . Dogs 150 may have a rectangular, circular, or other shape as required. Dogs 150 may also be constructed integral to second portion 400 . Second portion 400 also has a plurality of contact members 120 attached to the outer surface.
First and second clamp portions 300 , 400 are preferably constructed from a material similar to that used to construct the casing and tubing used in the well. For instance, in a well using standard carbon steel pipe, portions 300 , 400 may be constructed from a cast steel material. The use of a similar material simplifies the attachment of contact members 120 and also provides for improved data gathering by minimizing the signal loss as a signal travels across different components. In a well having a composite casing or using composite tubing, upper and lower portions 300 , 400 may be constructed from a composite or other non-metallic material.
During installation, first clamping portion 300 , containing sensor 130 , and second clamping portion 400 , including dogs 150 , are placed around tubing 110 . Portions 300 , 400 are compressed against tubing 110 and each other and attachment members (not shown) are installed through attachment holes 320 and 420 . The compressive force necessary to securely attach portions 300 and 400 to each other and to tubing 110 may be provided by a hydraulic press, or other type of preloading device, so as to minimize the size of attachment members required. Sensor 130 and dogs 150 bear against tubing 110 to prevent any relative motion between tubing 110 and clamp assembly 100 . Once first portion 300 is securely attached to second portion 400 on tubing 110 , assembly 100 is ready for lowering into a wellbore.
Sensor 130 is normally a single sensor component of a sensor array. A sensor array may contain five sensors 130 connected in series on either side of a central processing unit. Individual sensors 130 are normally connected to adjacent sensors and then central unit by small tubing or cable, therefore the relative position of sensors 130 must be maintained. Access holes 350 are provided to allow access to sensor 130 as it is installed in clamp assembly 100 .
Referring now to FIGS. 3 a - 3 e , clamp assembly 100 is shown disposed within casing 500 in a highly deviated or horizontal wellbore. As can be seen in FIGS. 3 a - 3 e , the mass of tubing 110 forces assembly 100 against the lower portion of casing 500 . Regardless of the orientation of tubing 110 , clamp assembly 100 comes to rest, preferably on contact members 120 , against the inside of casing 500 . Therefore, sensor 130 is set in a stable, reliable relationship with casing 500 . The mass of tubing 110 maintains the position of assembly 100 within casing 500 so that sensor 130 can detect signals from the surrounding formation.
Therefore, the embodiments of the present invention provide a sensor assembly that creates a stable, reliable connection between sensor 130 , tubing 110 , and the well casing 500 . By utilizing tubing 110 and attachment assembly 100 , a simple, robust arrangement for disposing a sensor is provided in a highly deviated or horizontal wellbore. One preferred clamping assembly 100 is described but any assembly that is capable of maintaining a secure connection can be used.
The embodiments set forth herein are merely illustrative and do not limit the scope of the invention or the details therein. It will be appreciated that many other modifications and improvements to the disclosure herein may be made without departing from the scope of the invention or the inventive concepts herein disclosed. Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, including equivalent structures or materials hereafter thought of, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense. | A method and apparatus, for deploying a sensor attached to tubing in a highly deviated or horizontal wellbore, that are characterized by a stationary attachment system that securely fixes a sensor to a tubing string such that the sensor is coupled to the casing regardless of the orientation of the tubing within the wellbore. One preferred embodiment includes a clamp assembly that encloses the sensor and clamps around the cubing string. The clamp assembly further includes a plurality of contact members that provide stable contact points between the well casing and the clamp assembly. The embodiments of the present invention act to maintain the sensor in a stable coupling with the casing without any actuation required for installation. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefits of priority to Korean Patent Application No. 10-2009-0001983 (filed on Jan. 9, 2009), which is herein incorporated by reference in its entirety.
FIELD
[0002] The present invention relates to an air conditioner.
BACKGROUND
[0003] Generally, an air conditioner, which is an apparatus for heating or cooling air using a refrigerant cycle, is sorted into a household air conditioner and an industrial air conditioner.
[0004] The household air conditioner may include a separate type air conditioner in that an indoor unit and an outdoor unit are separated and an integrated type air conditioner in that an indoor unit and an outdoor unit are combined. The indoor unit of the separate type air condition can be sorted into a wall mounted type indoor unit that is mounted on a wall, a standing type indoor unit that stands on a bottom part, and a ceiling type (or cassette type) indoor unit that is mounted on a ceiling.
[0005] A structure where an Infra-Red (IR) sensor or a Pyroelectric Infra-Red (PIR) sensor, etc., is mounted on one side of the indoor to concentratedly supply cool air or warm air to a spot of the space in which indoor resident is positioned has been disclosed.
SUMMARY
[0006] In one aspect, an air conditioner includes a cabinet configured to mount on an indoor ceiling. The air conditioner also includes a front panel coupled to the cabinet and having an air inlet and outlet. The The air conditioner further includes a suction panel coupled to the front panel and configured to move between an open positione in which air is able to circulate through the air conditioner and a closed position in which air is blocked from circulating through the air conditioner. The air conditioner further includes a sensor unit that is mounted on the suction panel, that is configured to move together with the suction panel and that is configured to detect a position of a person in the indoor place. In addition, a controller configured to adjust a direction of air flow from the outlet based on the deteded position of the person.
[0007] Implementations may include one or more of the following features. For example, the sensor unit is mounted on an edge part of the suction panel. The sensor unit is mounted on a central part of the suction panel.
[0008] In some implementations, The sensor unit includes a sensing element configured to rotate forward or reversely in response to a driving signal generated by a driving motor. The sensor unit also includes a sensor cover configured to cover the sensing element. The sensor cover is defined in a cylindrical shape or its bottom part has a convexly curved shape. The sensor cover is defined as an opaque body or material.
[0009] In some examples, the sensor unit further detects movement of the person in the indoor. The sensor unit further detects heat radiated from the person and generates a control signal to control a temperature of air output by the air conditioner based on comparing the detected the radient heat with a reference value. An amount of rotation of a discharge vane is adjusted by the controller.
[0010] In another aspect, an air conditioner includes a cabinet configured to mount on an indoor ceiling. The air conditioner also includes a front panel coupled to the cabinet. The air conditioner further includes a suction panel coupled to the front panel and configured to move between an open position in which air is able to circulate through the air conditioner and a closed position in which air is blocked from circulating through the air conditioner. The air conditioner further includes a sensor unit mounted on the suction panel configured to move together with the suction panel, configured to detect a position of a person and configured to start the detection in connection with movement of the suction panel during an initial stage of the air conditioner. In addition, a controller configured to adjust a direction of air flow from the outlet based on the deteded position of the person.
[0011] Implementations may include one or more of the following features. For example, the sensor unit includes a sensing element configured to rotate forward or reversely in response to a driving signal generated by a driving motor. The sensing unit also includes a sensor cover configured to cover the sensing element.
[0012] In some implementations, the sensor cover is defined in a cylindrical shape or its bottom part has a convexly curved shape. The sensor cover is defined as an opaque body or material. The sensor unit is configured to start the detection after the movement of the suction panel is completed.
[0013] In yet another aspect, an air conditioner includes a cabinet configured to mount on an indoor ceiling. The air conditioner also includes a front panel coupled to the cabinet. The air conditioner further includes a suction panel coupled to the front panel configured to move between an open position in which air is able to circulate through the air conditioner and a closed position in which air is blocked from circulating through the air conditioner. The air conditioner further includes a sensor unit that is mounted on the suction panel, that is configured to move together with the suction panel and that is configured to detect a position of a person in the indoor place,wherein the detection is started indepentantly from the movement of the suction panel during an initial stage of the air conditioner. In addition, a controller configured to adjust a direction of air flow from the outlet based on the deteded position of the person.
[0014] Implementations may include one or more of the following features. For example, the sensor unit includes a sensing element configured to rotate forward or reversely in response to a driving signal generated by a driving motor. the sensor unit also includes a sensor cover configured to cover the sensing element.
[0015] In some implementations, the sensor cover is defined in a cylindrical shape or its bottom part has a convexly curved shape. The sensor cover is defined as an opaque body or material. The sensor unit starts the detection in response to power on of the air conditioner.
[0016] In yet another aspect, an air conditioner includes a cabinet configured to mount on an indoor place. The air conditioner also includes a front panel coupled to the cabinet. The air conditioner further includes a suction panel coupled to the front panel and configured to move between an open positions in which air is able to circulate through the air conditioner and a closed position in which air is blocked from circulating through the air conditioner. The air conditioner further includes a sensor unit mounted on the suction panel and configured to detect a position of a person or moving object when the air conditioner is in a power off state or a sleeping mode. In addition, the air conditioner includes a controller configured to control the air conditioner to power on from the power off state or the sleeping mode in response to the deteded position.
[0017] Implementations may include one or more of the following features. For example, the sensor unit is configured to start the detection in connection with the movement of the suction panel during an initial stage of the air conditioner. The sensor unit configured to start the detection independently from the movement of the suction panel during an initial stage of the air conditioner.
[0018] In yet another aspect, an air conditioner includes a front panel coupled to the cabinet. The air conditioner also includes a suction panel coupled to the front panel and configured to move between an open positions in which air is able to circulate through the air conditioner and a closed position in which air is blocked from circulating through the air conditioner. The air conditioner further includes a sensor unit mounted on the suction panel and configured to detect a position of a person or moving object when the air conditioner is in a power off state or a sleeping mode. In addition, a controller configured to control the air conditioner t to turn off the power in response to determining that no person or moving object is detected.
[0019] In yet another aspect, an air conditioner includes a front panel coupled to the cabinet. The air conditioner also includes a suction panel coupled to the front panel and configured to move between an open positions in which air is able to circulate through the air conditioner and a closed position in which air is blocked from circulating through the air conditioner. The air conditioner further includes a sensor unit mounted on the suction panel and configured to detect a position of a person or moving object when the air conditioner is in a power off state or a sleeping mode. In addition, a controller configured to control the air conditioner to decrease an amount of air flow in response to determining that no person or moving object is detected.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a perspective view of a ceiling type air conditioner;
[0021] FIG. 2 is a longitudinal cross-sectional view schematically showing an inner configuration of the air conditioner in FIG. 1 ;
[0022] FIG. 3 is an external appearance perspective view of a sensor unit; and
[0023] FIG. 4 is a side view showing a configuration of a detecting unit.
DETAILED DESCRIPTION
[0024] Referring to FIGS. 1 and 2 , a ceiling type air conditioner having an indoor unit 10 includes a cabinet 11 that defines an external appearance, a front panel 12 that is coupled to a lower end of the cabinet 11 , a suction panel 13 that is elevatably coupled to the front panel 12 , a heat exchanger 17 that is enclosed around an inner side of the cabinet 11 , a fan assembly 14 that is positioned in an inner side space of the heat exchanger 17 , a shroud 16 that is positioned at a lower side of the fan assembly 14 to guide a flow of the sucked air, a filter 15 that is positioned on an upper end of the shroud 16 to purify the sucked air; and a sensor unit 20 that is mounted on one side of the suction panel 13 to detect a position and movement of indoor residents. The sensor unit 20 may be an Infra-Red sensor using infrared rays.
[0025] In detail, an edge part of the front panel 12 is connected with four outlets 121 . Each outlet 121 has a discharge vane 30 that is rotatable. And, the direction of air is controlled based on the rotation angle of the discharge vane. When a position of a indoor resident is detected by the sensor unit 20 , the rotation angle of the discharge vane 30 is controlled by a controller to provide air to the resident.
[0026] In addition, the central part of the front panel 12 has an inlet 111 for sucking the indoor air and the inlet 111 is selectively shielded by the suction panel 13 . A plurality of racks 18 are extended to the upper surface of the suction panel 13 . A pinion 19 that is positioned on a upperside of the front panel 12 is coupled to the rack 18 and a driving motor. The pinion 19 is rotated by driving the driving motor. Therefore, the suction panel 13 can move a predetermined distance between the upper and lower positions by the operations of the rack 18 and pinion 19 . And, the inlet 111 is selectively opened and closed by the movement of the suction panel 13 . It is to be noted that the moving unit of the suction panel 13 is not limited to the foregoing rack/pinion structure.
[0027] In addition, air that includes foreign materials sucked through the inlet 111 are filtered by passing through the filter 15 and the filtered air is sucked toward the fan assembly 14 . The fan assembly 14 includes a centrifugal fan 142 and a fan motor 141 for driving the centrifugal fan 142 . The centrifugal fan 142 is configured to direct a air flow from a suction part of the air conditioner to radical discharge part of the air conditioner as shown in FIG.2 . The air sucked by the fan assembly 14 passes through the heat exchanger 17 and is then provided to the room through the outlet 121 .
[0028] In some examples, the sensor unit 20 is mounted on the suction panel 13 and its mount position may be mounted on one side edge of the suction panel 13 as shown in FIG. 1 and FIG. 2 . Alternatively, the sensor unit 20 may be mounted at the central part of the suction panel 13 .
[0029] If a sensor unit 20 is mounted on the one side of the front panel 12 , the suction panel 13 can serve as an obstacle because the suction panel 13 is located at the lower position. For instance, the infrared rays sent from the sensor unit 20 impinge on the suction panel 13 , such that the sensor unit 20 cannot detect a position of a resident in a room. However, if the sensor unit 20 is mounted on the suction panel 13 , the above obstacle may be reduced. As a result, the phenomenon of limiting the sensing range due to moving the suction panel 13 may be reduced.
[0030] Further, as radiating infrared rays are received by a sensing element that is positioned inside the sensor unit 20 , the sensing element of the sensor unit 20 can be rotated 360° by a driving unit. The configuration and operation of the sensor unit 20 will be described below with reference to FIGS. 3 and 4 .
[0031] Referring to FIGS. 3 and 4 , the sensor unit 20 includes a case 21 connecting a part of the detecting unit shown in FIG. 4 and a sensor cover 22 coupled to the lower end of the case 21 . A bracket 211 is extended to the outer circumferential surface of the case 21 and the bracket 211 is fixed to the upper surface of the suction panel 13 by a connection member. The sensor cover 22 is defined in a cylindrical shape and its bottom surface has a convexly curved shape, having a predetermined curvature. The bottom surface of the sensor cover 22 is convexly curved, such that the refraction of the signal radiated from the detecting unit is minimized. The sensor cover 22 can be made of opaque materials and has a thickness that can easily transmit the infrared signal radiated from the detecting unit. For example, the sensor cover 22 is made of opaque materials, such that the indoor resident does not misunderstand the sensor as a surveillance camera. Although that, as explained, the sensor can transmit most infrared signals to easily detect the indoor resident. Only the convex bottom part of the sensor cover 22 may be exposed to the indoor.
[0032] The detecting unit includes a sensing element 23 that radiates the sensing signals such as infrared rays, a circuit board 24 coupled to the sensing element 23 and has circuits for the operation of the sensor unit mounted thereon, a supporter 25 that supports the circuit board 24 , and a driving motor 26 that is connected to the lower side of the supporter 25 to rotate the supporter 25 .
[0033] In addition, the rotation shaft 261 of the driving motor 26 is connected to the lower end of the supporter 25 . The upper surface of the supporter 25 is connected to the circuit board 24 and configured to be inclined at a predetermined angle as shown FIG. 4 . Therefore, the sensing element 23 can rotate 360° at the state inclined at a predetermined angle from a vertical line, such that the sensing range is extended. The sensing element 23 is mounted to be inclined from a vertical line, such that the bottom surface of the sensor cover 22 is defined in a convexly curved shape, thereby making it possible to minimize the refraction phenomenon of the infrared signals radiated from the sensing element 23 . For example, the infrared rays radiated from the sensing element 23 are orthogonal to a tangential line that passes through the bottom surface of the sensor cover 22 corresponding to a point through which the infrared rays pass, such that the signals radiated from the sensing element 23 can effectively transmit the sensor cover 22 .
[0034] The driving motor 26 may be a step motor that can rotate forward or reversely and the sensing element 23 also rotates 360° forward and then rotates 360° reversely by the forward/reverse rotation of the driving motor 26 .
[0035] If an operation instruction from the indoor unit 10 is provided to the sensor unit 20 , the driving motor 26 can rotate in a forward direction and then rotate in a reverse direction at a predetermined time interval. For example, the driving motor rotates in a forward direction at a predetermined speed and then rotates in a reverse rotation at the same speed. The driving motor performs the forward direction and the reverse rotation again after the predetermined time elapses. The sensing signal is transmitted from the sensing element 23 and returned to the sensing element reflected by the residents, thereby detecting the position of the residents in the indoor, room or space. The sensing element 23 can detect the position or movement of the resident as well as detect heat radiated from the resident, making it possible to detect the state of the resident by the controller. For example, in the heating mode, if the heat radiated from the resident is lower than a reference value stored in the memory of the controller, it is determined that the resident feels a chill, thereby making it possible to control the rotation angle of the discharge vane 30 to provide heated air to the resident. The sensing element 23 may start detecting a position of the resident after the movement of suction panel 13 is completed. When the air conditioner is turned on or activated from a sleeping state, the suction panel 13 moves toward a lower position from the ceiling. After the movement of the suction panel 13 is completed or almost completed, an instruction signal is sent to the sensing unit 24 from the indoor unit 10 and then the driving motor 26 drives the sensing element 23 to search a position of the resident in the room. The sensing element 23 then sends an infrared signal and receives the infrared signal reflected by the person in the room. Based on the movement of sensing element 24 , for example rotating forward or reverse, the sensing unit 23 can detect any object or person currently in the room. The sensing element 23 is located in the lowest position from the bottom of the room, there is no obstacle when the sensing element 23 sends and receives the infrared signal to detect the person in the room. In this implementation, in a sleeping mode, an activating temperature of the air conditioner to activate the air conditioner based on the setting temperature is adjusted to higher than an activating temperature of the air conditioner that user sets. For example, the activating temperature of the air conditioner is adjusted three degree up comparing to a current a activating temperature of the air conditioner.
[0036] As another example, the sensing element 23 may start a sensing operation earlier than the above implementation. For example, the sensing element starts detecting an object in response to power on signal of the air conditioner. When the air conditioner is turned on or activated from a sleeping state, the suction panel 13 moves toward a lower position from the ceiling. While the suction panel is moving, the sensing unit 24 carries out the search operation in response to an instruction signal from the controller of the air conditioner. Therefore, a cool air generated by the air conditioner can be supplied to the resident as soon as the operation of the air conditioner begins.
[0037] In addition, the sensing unit 20 can control the air conditioner in response to detecting a moving object or person in the room. In this implementation, the sensing element 23 can search an object or a person in the room periodically for example, every one minute while the air conditioner is turned off. The sensing element 23 may have a separate power source such as a battery or may have a different power line from the air conditioner for this operation. If a person comes into the room while the air conditioner turns off, the sensing unit 20 can detect a position of the person in response to receiving the sensing signal, and then sends a command to the air conditioner. In response to the command, the air conditioner turns on, the suction panel moves down from ceiling, and air passes through the inlet 111 , a heat exchange 17 and a discharge vane 30 sequentially. Therefore, a cool air can be supplied to the person in response to detection the position of the person in the room. Alternatively, the command can be generated in the controller of the air conditioner. In this case, the controller has a power source.
[0038] Furthermore, if the sensing element can not detect a person for a predetermined time, another control signal is provided to the air conditioner. For example, when the person leaves the room, the sensing element 23 can not detect any moving object any more. If the sensing element 23 can not detect any object or person for a predetermined time such as five minutes, the sensor unit 20 sends an another command to the air conditioner. The air conditioner is then turned off or decreases an amount of the cool air in response to the command signal. Those operations are controlled by the controller of the air conditioner. Another implementation is that, in response to the command signal, the air conditioner decreases the amount of the cool air for a predetermined time, for example thirty minutes, and then turns off. In this implementation, instead of power off, the air conditioner may be set to the sleeping mode. For example, an activating temperature may be changed three degree higher than an activating temperature that the air conditioner currently is set.
[0039] It will be understood that various modifications may be made without departing from the spirit and scope of the claims. For example, advantageous results still could be achieved if steps of the disclosed techniques were performed in a different order and/or if components in the disclosed systems were combined in a different manner and/or replaced or supplemented by other components. Accordingly, other implementations are within the scope of the following claims. | Disclosed is an air conditioner includes a cabinet that is configured to mount on an indoor ceiling. The air conditioner also include a front panel that is coupled to the cabinet and having an air inlet and outlet. The air conditioner further include a suction panel that is coupled to the front panel and configured to move between an open positione in which air is able to circulate through the air conditioner and a closed position in which air is blocked from circulating through the air conditioner. The air conditioner further include a sensor unit that is mounted on the suction panel, that is configured to move together with the suction panel and that is configured to detect a position of a person in the indoor place. In addition, the air conditioner also include a controller adjusting a direction of air flow from the outlet based on the deteded position of the person. | 5 |
FIELD OF INVENTION
The invention relates to telephone systems, and in particular, to generating ringing voltages in such systems.
RELATED APPLICATIONS
This application claims the Aug. 17, 2001 priority date of German patent application 101 40 357.7, the contents of which are herein incorporated by reference.
BACKGROUND
When calling a subscriber in a telephone system, as is known, a ringing signal sounds which is generally generated at a central location (the exchange). For this purpose, telephone systems comprise ringing generators for generating a ringing voltage which is output after amplification by an SLIC (Subscriber Line Interface Circuit) onto the transmission line.
In this case, the ringing voltage output by the SLIC must satisfy certain requirements specified e.g. in the reference: Telcordia (Bellcore) Technical Reference TR NWT 000057 for DLC systems. In accordance with TR NWT 57,a ringing voltage of at least 40 Vrms must be present across a maximum permitted ringing load of five REN (Ringer Equivalent Number), that is to say a maximum of five telephones connected in parallel, given a maximum line length [sic] of 930 ohms. In this case, the SLIC would have to supply a ringing voltage of approximately 70 Vrms and a current of approximately 29 mA would flow. By contrast, if the load is present directly at the exchange, that is to say the transmission line is short and only has a resistance of 400 ohms, for example, it is not necessary to feed a ringing voltage of 70 Vrms into the line in order to satisfy the minimum requirement of 40 Vrms across the load. A ringing voltage of about 43 Vrms fed in by the SLIC would be sufficient in this case. If 70 Vrms are nevertheless fed in, a current of about 47 mA flows. Thus, approximately 60% more current flows than would be necessary for the five REN, with correspondingly more power being consumed.
In battery-fed applications or applications which must still maintain the telephone service during a mains voltage failure (life support systems) and utilize batteries for this purpose, such as, for example, ISDN NTs (network terminations) or DLC (digital loop carrier) systems, a high power loss is disadvantageous.
It is known to use external ringing generators, i.e. ringing generators arranged outside a CODEC (coder-decoder), which supply a plurality of transmission lines with a ringing signal and switch the ringing signal to a desired line via relays. In order to keep the current as small as possible with short transmission lines, different resistors are connected downstream of the ringing generators, depending on the length of the transmission line. However, as a result of this measure, the no-load voltage is considerably increased and the power loss rises accordingly.
SUMMARY
Therefore, the object of the present invention is to lower the power loss in the ringing mode.
The essential concept of the invention consists in controlling the ringing voltage output by an SLIC in a manner dependent on the load to be driven, which load is essentially determined by the length of the transmission line. For this purpose, provision is made of a controllable ringing generator with a control device for controlling the ringing voltage output by the SLIC.
In order to determine the length of the transmission line, the current flowing on the transmission line in the ringing mode (during ringing) is preferably measured. The measured current value is a measure of the length of the transmission line and serves as a manipulated variable for the control device.
In accordance with a preferred embodiment of the invention, the controllable ringing generator comprises a ringing generator for generating a ringing signal with a constant amplitude (constant ringing generator).
In accordance with one refinement of the invention, the control device generates, in a manner dependent on the measured current value, a multiplication factor by which the ringing signal of the constant ringing generator is multiplied.
In order to evaluate the measured current value, provision may be made of a rectifier and integration circuit, by means of which the current measurement signal supplied by the measuring device is rectified and integrated. The integration of the current measurement signal is preferably effected over a period of the ringing signal.
In accordance with a preferred embodiment of the invention, provision is made of a device for determining a zero crossing of the ringing signal, in order to determine the integration duration.
The controllable ringing generator is preferably programmable. The ringing voltage for a lower current threshold value and an upper current threshold value may preferably be set in the control device of the ringing generator. The control device can thus be set in a simple manner to different standards and therefore to different minimum preconditions for the ringing voltage.
If a current which is less than the lower current threshold value flows on the transmission line in the ringing mode, then the ringing voltage output by the SLIC is preferably controlled to a constant maximum value. By contrast, if a current which is greater than the upper current threshold value flows in the ringing mode, then the ringing voltage output by the SLIC is preferably set to a constant minimum value.
In accordance with a preferred embodiment of the invention, the measuring device for measuring the current carried on the line is arranged in the SLIC.
The CODEC of the telephone system preferably comprises a device for generating a DC offset for off-hook identification (i.e. for identifying whether the telephone receiver has been taken off-hook).
The solution described above additionally has the advantage that only the AC ringing voltage and not the DC voltage is reduced, as a result of which the off-hook identification is not influenced.
BRIEF DESCRIPTION OF THE FIGURES
The invention is explained in more detail below by way of example with reference to the accompanying drawings, in which:
FIG. 1 shows an exemplary embodiment of a telephone system with controlled ringing voltage according to the invention;
FIG. 2 shows the profile of the ringing voltage in the telephone system from FIG. 1 as a function of the current flow; and
FIG. 3 shows the profile of the ringing voltage with or without control.
DETAILED DESCRIPTION
FIG. 1 shows a detail from a telephone system with a telephone 1 of a network subscriber and a CODEC (coder/de-coder), which is usually arranged in an exchange. The interface between CODEC 3 and telephone 1 is formed by an SLIC 2 (subscriber line interface circuit), which outputs not only audio signals but also a ringing signal to the telephone 1 . The signals are transmitted via the transmission line 17 between SLIC 2 and telephone 1 .
In order to generate ringing signals a controllable ringing generator 16 is provided, which comprises a constant ringing generator 12 for generating an AC voltage with a constant amplitude and also a control device 14 . The controllable ringing generator 16 is arranged in the CODEC DSP (digital signal processor) 15 .
Furthermore, a low-pass filter 10 is provided, which filters the ringing signal in order to suppress disturbances. For hook identification (identifying whether the telephone receiver of the telephone 1 has been placed on-hook or taken off-hook), a DC component (DC offset) generated by a corresponding device DC offset 11 is also added to the ringing signal at the addition node 18 .
The resulting signal is subjected to analog conversion by means of a DA converter 7 and output to the SLIC 2 , which amplifies the ringing voltage and outputs it onto the transmission line 17 .
The total load to be driven essentially results from the impedance of the telephone 1 , the resistor 4 of the transmission line 17 and resistors 5 which are arranged for protection against overload, e.g. due to a flash of lightning, in the transmission line 17 .
In order to determine the length or the resistance of the transmission line 17 , a measuring device is arranged in the SLIC 2 , and continuously measures the current carried on the transmission line 17 . The measured current value is fed to an AD converter 6 and a rectifier and integration circuit 9 connected thereto, which circuit integrates the rectified signal.
The integration is best effected over a period of the ringing signal generated by the constant ringing generator 12 . In order to determine the integration period, there is arranged a device 8 for identifying zero crossings of the ringing signal, which device is connected to the constant ringing generator 12 and the rectifier and integration circuit 9 .
The measured current value output by the rectifier and integration circuit 9 can then be averaged over a plurality of values or be subjected to low-pass filtering by means of corresponding devices (not shown).
The measured current value is finally fed to the control device 14 , which controls the ringing voltage Va, b (desired variable) output by the SLIC 2 to a predetermined value in a manner dependent on the measured current value. For this purpose, the control device 14 generates multiplication factors by which the ringing signal generated by the constant ringing generator 12 is multiplied at the multiplication node 13 .
FIG. 2 shows the profile of the ringing voltage Va, b output by the SLIC 2 for different line lengths of the transmission line 17 . In this case, the dotted line a represents the total load for the maximum permissible line length and the line b represents the total load for a very short line length.
The ringing voltage Va, b is controlled linearly in a region between a lower current threshold value I 1 (longest line length) and an upper current threshold value I 2 (shortest line length). If the current measurement yields a current flow of less than I 1 (e.g. 30 mA), then a constant maximum voltage V 1 (e.g. 70 Vrms) is output. If the current measurement yields a current flow of more than I 2 (e.g. 90 mA), then a constant minimum voltage V 2 (e.g. 45 Vrms) is output. The minimum voltage V 2 preferably lies at a value just above the required minimum ringing voltage at the telephone (e.g. 40 Vrms). This ensures that the minimum ringing voltage prescribed by the respective standard is present at the telephone 1 .
The resistance defined by the gradient of the straight lines between the values I 1 , V 1 and I 2 , V 2 could also be realized as a real resistance. In the case of the illustrated resistance of about 5 kohms, however, a no-load voltage of approximately 220 V would result, which is not possible for an IC ringing generator. A smaller resistance of e.g. 1 kohm would be possible with regard to the no-load voltage, but would result in a smaller control range.
The controllable ringing generator 16 is additionally programmable, so that a user only has to select the minimum and maximum voltages (V 1 , V 2 ) and the corresponding currents (I 1 , I 2 ) in order to adapt the control to predetermined requirements.
FIG. 3 shows the temporal profile of the ringing voltage with control (curve c) and without control (curve d). As can be discerned, the amplitude of the ringing voltage Va, b is already reduced to the final, lower value after about 0.2 s as a result of which the power loss is correspondingly reduced. | A telephone system includes a controllable ringing generator for generating a ringing signal and an interface for providing a ringing voltage derived from that signal on the transmission line. The controllable ringing generator includes a control device for controlling the ringing voltage in response to the ringing current. | 8 |
The present invention relates to a novel process for preparing the E-isomer of 1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one (hereinafter referred to as "triazolyl styryl ketone derivative") of the formula (I): ##STR3##
BACKGROUND OF THE INVENTION
It is known that the triazolyl styryl ketone derivative (I) itself is usful as an antimicrobial agent [cf. Japanese Patent First Publication (Kokai) No. 130661/1978], and that triazolyl styryl carbinol of the formula (II): ##STR4## which is obtained by reduction of the above derivative (I) is more useful as an antimicrobial agent, a herbicide, a plant growth regulator, or the like, and it is also known that the effect of the E-isomer thereof is particularly superior to that of the Z-isomer [cf. Japanese Patent First Publication (Kokai) No. 41875/1979, 124771/1980 and 25105/1981].
Accordingly, it is desirable to provide a process for efficiently preparing the E-isomer of the triazolykl styryl ketone derivative of the above formula (I) which is a starting material for preparing the E-isomer of the above compound of the formula (II) h(hereinafter the E-isomer, the Z-isomer and a mixture of the E-isomer and the Z-isomer of the triazolyl styryl ketone derivative (I) are simply refered to as "E-isomer", "Z-isomer" and "E/Z-isomer", respectively, unless specified otherwise). As a process for satisfying such requirements, for example, the following processes are proposed:
(1) A process of isomerizing Z-isomer or E/Z-isomer into E-isomer with light [cf. Japanese Patent First Publication (Kokai) No. 147265/1980].
(2) A process of isomerizing Z-isomer or E/Z-isomer with a compound such as an aromatic mercaptan [cf. Japanese Patent First Publication (Kokai) No. 147265/1980].
(3) A process of separating E/Z-isomer with a chromatography [cf. Jpanese Patent First Publication (Kokai) No. 147265/1980].
(4) A process of separating E-isomer from E/Z-isomer, which comprises treating E/Z-isomer with sulfuric acid, precipitating and separating the sulfuric acid salt of E-isomer, and decomposing the salt to obtain E-isomer [cf. Japanese Patent First Publication (Kokai) No. 140081/1983].
However, these processes have problems such as, for example, the mecessity of a special reaction apparatus or the necessity of an additional treatment for separating E- and Z-isomers from the reaction products because of an insufficient isomerizatio rate. Moreover, in the case of the process for merely separating E-isomer from E/Z-isomer such as the process (4), the yield of the E-isomer is dependent on the E-isomer content contained in the starting E/Z-isomer and the treatment of the residual Z-isomer is also necessary.
BRIEF DESCRIPTION OF THE INVENTION
In view of the above circumstances, the present inventors have extensively investigated a process which is free from the above problems and can produce easily and effectively the desired E-isomer from Z-isomer or E/Z-isomer on an industrial scale and in a good yield, and have found a process which can perform simultaneously the isomerization of Z-isomer or E/Z-isomer and the separation of E-isomer and can satisfy the above-mentioned requirements.
Thus, the object of the present invention is to provide a novel process for preparing the E-isomer of the triazolyl styryl ketone derivative of the above formula (I), which comprises treating the Z-isomer of the derivative which may contain the E-isomer with an acid and an isomerization catalyst in an organic solvent, precipitating and separating the resulting salt of the E-isomer from the solution, and decomposing the precipitate to obtain the E-isomer of the derivative free from the acid.
DETAILED DESCRIPTION OF THE INVENTION
The starting material used in the present invention may be either Z-isomer or E/Z-isomer, i.e. a mixture of E-isomer and Z-isomer wherein the E-isomer content is not limited.
The acid used in the present invention includes sulfuric acid, sulfonic acids (e.g. methanesulfonic acid, ethanesulfonic acid, etc.), hydrohalogenic acids (hydrochloric acid, hydrobromic acid, etc.), nitric acid, chloric acid, perchloric acid, aliphatic carboxylic acids (e.g. acetic acid, propionic acid, etc.) and the like. Among these acids, the preferable ones are sulfuric acid or methanesulfonic acid. Although the amount of the acid varies depending on the kind of acid, it is usually used in an amount of 0.5 to 3 moles, preferably 0.8 to 1.2 moles, per 1 mole of the starting Z-isomer or E/Z-isomer. An appropriate amount of water may optionally be added when the acid is used.
The isomerization catalyst used in the present invention is not limited and may be any isomerization catalysts which have an ability to isomerize Z-isomer into E-isomer in the presence of an acid. The preferable isomerization catalyst includes compounds which can form a halonium ion, and includes, for example, halogens (e.g. chlorine, bromine, iodine, etc.), halohalides (e.g. iodine monobromide, etc.), cyanogen halides (e.g. cyanogen bromide, etc.) N-halocarboxylic amides or N-halodicarboxylic imides (e.g. N-bromosuccinimide, N-bromoacetamide, N-bromocaprolactam, N-bromophthalimide, etc.), hypohalogenous acids (e.g. trifluoroacetyl hypobromite, etc.), complexes of a halogen with an organic compound (e.g. triphenylphosphine dibromide, etc.), and the like. The isomerization catalyst is usually used in an amount of 0.0001 to 1.0 mole, preferably 0.001 to 0.1 mole, per 1 mole of the starting Z-isomer or Z-isomer contained in E/Z-isomer.
The solvent used in the present invention is not limited and includes, preferably, aprotic organic solvents, for example, aromatic hydrocarbons (e.g. benzene, xylene, toluene, etc.), halogenated hydrocarbons (e.g. dichloromethane, chloroform, carbon tetrachloride, dichloroethane, trichlene, perchlene, monochlorobenzene, dichlorobenzene, etc.), esters (e.g. ethyl acetate, ethyl formate, etc.), ethers (e.g. diethyl ether, tetrahydrofuran, etc.), aliphatic or alicyclic hydrocarbons (e.g. hexane, heptane, octane, petroleum ether, cyclohexane, etc.), and a mixture thereof. Although the amount of the solvent varies largely depending on, for example, the kind of the solvent, the kind of the isomerization catalyst, and the like, it is usually used in an amount of 0.5 to 20-fold by weight of the starting Z-isomer or E/Z-isomer.
The reaction is usually carried out at a temperature of from 0° to 20° C., preferably from 30° to 150° C., for 0.5 to 48 hours.
The isomerization of Z-isomer into E-isomer proceeds by treating Z-isomer or E/Z-isomer with an acid and an isomerization catalyst, by which a salt of E-isomer is produced. After the reaction, the reaction mixture is cooled to precipitate the salt of E-isomer from the mixture. In general, the salt of E-isomer precipitates spontaneously, as a crystal, from the reaction mixture with the progress of the reaction, or by cooling the reaction mixture, while a seed crystal may be used to ensure the precipitation of the salt.
The separation of the precipitated salt of E-isomer from the reaction mixture is carried out by a conventional method such as filtration, centrifugation, decantation, or the like.
The recovery of E-isomer from the salt of E-isomer is carried out by salt-decomposition or neutralization of the resulting salt. For example, the salt of E-isomer can be decomposed by mixing the salt with an excess of water and a solvent which is immiscible with water and can dissolve E-isomer (e.g. toluene, monochlorobenzene, etc.), to obtain a high purity of E-isomer from the organic layer. The decomposition of the salt of E-isomer may also be carried out by using a protic solvent except water (e.g. methanol, acetic acid, etc.). Alternatively, E-isomer can be obtained by neutralizing the salt thereof with an aqueous solution of a base such as sodium hydroxide, sodium bicarbonate, sodium carbonate, or the like.
According to the present invention, Z-isomer can easily be isomerized into E-isomer in a good yield on an industrial scale, without using a special apparatus. Moreover, a high purity of E-isomer which does not contain any substantial amount of by-product can be obtained.
The present invention is illustrated by the following Examples, but should not be construed to be limited thereto. In the Examples, "%" and "ratio" mean "% by weight" and "ratio by weight", respectively, unless specified otherwise.
EXAMPLE 1
Z-isomer of 1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one (2.5 g) was dissolved in carbon tetrachloride (10 g), and thereto were added dropwise conc. sulfuric acid (0.845 g; sulfuric acid content: 97%) and then bromine (0.041 g) at 20° C. After reacting the mixture at a temperature of from 40° C. to 50° C. for 20 days, the mixture was cooled to 20° C., and the resulting crystals were separated by filtration. The crystals were washed with chloroform (10 g), and thereto were added 10% aqueous sodium bicarbonate (2 g), chloroform (20 g) and water (10 g). After stirring the mixture at room temperature until the crystals disappeared, the aqueous layer was removed from the mixture, and the chloroform layer was washed twice with water and then concentrated to obtain E-isomer of 1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one. The yield of E-isomer to the starting Z-isomer was 79.8%, and the ratio of E-isomer to Z-isomer (hereinafter referred to as "E/Z ratio", unless specified otherwise) was 98.6/1.4.
EXAMPLES 2 AND 3
Using the same kind and amount of Z-isomer as used in Example 1, Example 1 was repeated to obtain E-isomer, except that a different kind of solvent and an amount thereof, a reaction temperature and a reaction time as shown in Table 1 were employed. The results are shown in Table 1.
TABLE 1__________________________________________________________________________Solvent Reaction Reaction Yield of Amount temperature time E-isomer E/Z ratioKind (g) (°C.) (days) (%) (by weight)__________________________________________________________________________Ex. 2 1,2-Dichloroethane 10 20-25 14 51.6 95.8/4.2 n-Heptane 10Ex. 3 Chloroform 10 40-45 4 69.5 99.4/0.6 n-Heptane 10__________________________________________________________________________
EXAMPLE 4
A crude mixture of E-isomer and Z-isomer of 1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one (5.0 g; E/Z ratio: 21.2/78.8) was dissolved in monochlorobenzene (20 g), and thereto were added dropwise conc. sulfuric acid (1.69 g; sulfuric acid content: 97%) and then bromine (0.082 g) at 20° C. After reacting the mixture at a temperature of from 40° to 45° C. for 4 days, the mixture was cooled to 20° C., and the resulting crystals were separated by filtration. The crystals were washed with chloroform (20 g), and thereto were then added 10% aqueous sodium bicarbonate (4 g), water (20 g) and chloroform (40 g), and the mixture was stirred at room temperature until the crystals disappeared. The aqueous layer was then removed from the mixture, and the chloroform layer was washed twice with water and concentrated to obtain E-isomer of 1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)- 4,4-dimethyl-1-penten-3-one. The yield of E-isomer to the starting E/Z-isomer was 51.6%, and the E/Z ratio was 97.4/2.6.
EXAMPLE 5
An E-isomer/Z-isomer mixture of 1-(4-chlorophenyl)-2-(1,2,4-traizol-1-yl)-4,4-dimethyl-1-penten-3-one (28.98 g; E/Z ratio: 30.5/69.5) was dissolved in monochlorobenzene (115.92 g), and thereto were added dropwise methanesulfonic acid (9.61 g) and then bromine (0.48 g) at 30° C. After reacting the mixture at 40° C. for 30 hours, the mixture was cooled to 25° C., and the resulting crystals were separated by filtration. The crystals were washed with monochlorobenzene (60 g), and thereto were added water (20 g) and monochlorobenzene (150 g), and the mixture was stirred at 60° C. until the crystals disappeared. The aqueous layer was then removed from the mixture, and the monochlorobenzene layer was washed with 5% aqueous sodium bicarbonate and water, and concentrated to obtain E-isomer of 1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one. The yield of E-isomer to the starting E/Z-isomer was 92.1%, and the E/Z ratio was 99.8/0.2.
EXAMPLE 6
A mixture of E-isomer and Z-isomer of 1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one (14.49 g; E/Z ratio: 30.5/69.5) was dissolved in monochlorobenzene (57.95 g), and thereto were added dropwise methanesulfonic acid (4.81 g) and then N-bromosuccinimide (0.44 g) at 30° C. After reacting the mixture at 80° C. for 2 hours, the mixture was cooled to 25° C. over about 4 hours, and the resulting crystals were separated by filtration. The crystals were washed with monochlorobenzene (30 g), and thereto were added water (10 g) and monochlorobenzene (75 g), and the mixture was stirred at 60° C. until the crystals disappeared. The aqueous layer was removed from the mixture, and the monochlorobenzene layer was washed with 5% aqueous sodium bicarbonate and water, and concentrated to obtain E-isomer of 1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one. The yield of E-isomer to the starting E/Z-isomer was 95.9%, and the E/Z ratio was 99.0/1.0. | A novel process for preparing the E-isomer of triazolyl styryl ketone derivative of the formula (I): ##STR1## is disclosed. The process includes treating the Z-isomer of the derivative which may contain the E-isomer of the derivative with an acid and an isomerization catalyst in an organic solvent, precipitating and separating the resulting salt of E-isomer from the solution, and decomposing the resulting precipitate to obtain the E-isomer of the derivative free from the acid. The E-isomer is useful for preparing the E-isomer of triazolyl styryl carbinol of the formula (II): ##STR2## which is useful as an antimicrobial agent, a herbicide, a plant growth regulator, or the like. | 2 |
REFERENCE TO RELATED APPLICATIONS
This is a continuing application of U.S. patent application Ser. No. 08/581,443, filed Dec. 29, 1995, now abandoned, and U.S. patent application Ser. No. 08/872,893, filed Jun. 11, 1997, now U.S. Pat. No. 5,881,538.
FIELD OF THE INVENTION
The present invention relates generally to the field of packaging and, more specifically, to the field of packaging computer disks (e.g., floppy disks, CD-ROMs, audio compact disks, etc.) in such a manner that the computer disks can be readily incorporated into a process for producing printed products.
BACKGROUND OF THE INVENTION
The printing industry has long recognized the need to have the ability to incorporate objects (i.e., other than standard signatures) into printed products (e.g., magazines). For example, it is known to attach empty envelopes, cologne samples and dehydrated food into a magazine. Customer demands and increased competition in the printing industry has led to the continued search for new objects that can be incorporated into printed products. Since each product is different in its size, shape and ability to withstand abuse, new products can require novel packaging techniques in order to ensure the product can survive the printing process and subsequent delivery to the consumer.
Due to the relatively recent surge in computer popularity, companies have begun using computer disks to convey information to potential customers. For example, some companies provide potential customers with computer disks that give textual and pictorial information about the company's products. In addition, computer disks can accompany an owners' manual to convey to the consumer information about the use of the product. The ability to store large amounts of information makes CD-ROMs particularly useful in conveying information to consumers for these purposes. However, sending the computer disks by direct mail can be cost prohibitive, thereby limiting the use of computer disks for this purpose. In addition, enclosing a computer disk with a product can require special packaging in order to avoid damage to the disk. A cheaper way of packaging and sending computer disks could significantly increase their use in advertising and for other purposes.
The printing industry has also recognized the need for flexibility in producing different versions of the same book to be mailed to users in the same geographical location, and the value of printing personalized messages (e.g. directed to a specific consumer or group of consumers) on each book. Ink jet printing is commonly used for producing such personalized messages on these types of books. In this regard, U.S. Pat. No. 5,100,116 discloses an apparatus that can print on the full page of signatures. The disclosed printing apparatus removes signatures from a stack and separates the signatures for printing. The signatures are subsequently fed to a collating conveyor where the signatures are gathered to form a book block.
SUMMARY OF THE INVENTION
One way of packaging and sending computer disks to consumers is to attach the computer disk to a printed publication, such as a magazine. In this manner, the computer disk could be sent at bulk rate magazine costs, which are significantly cheaper than direct mail costs. In addition, the disks can be targeted to the specific consumers that receive the particular publication. For example, a CD-ROM that advertises expensive luxury automobiles could be attached to an automotive magazine, or possibly to a magazine directed to wealthier individuals. Further, utilizing the present invention, computer disks can be attached directly to an owners' manual, thereby safely securing the computer disk in a printed publication (i.e., the owners' manual) and avoiding the need for extra packaging for the disk. The packaged disk can also be personalized with printed indicia (e.g., a person's name or access code) to further personalize the product.
The present invention provides a method of producing a printed product having a computer disk incorporated therein. The method includes the steps of providing a sheet of material, placing personalized indicia onto either the disk or the sheet of material, depositing the disk onto the sheet of material, folding the sheet of material over the disk to produce a package, gathering the package with a signature to produce a book block, and binding the book block to produce a printed product. The placing step can include the step of printing or the step of adding a label to either the disk or the sheet of material. The depositing step can include the step of positioning the disk over the personalized indicia such that the disk covers the personalized indicia. The placing step can occur either before or after the depositing step.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic perspective view of an apparatus that could be used to practice the present invention.
FIG. 2 is a top plan view of a web of material illustrating the relative positioning of adhesive and a computer disk immediately after the computer disk has been deposited onto the web.
FIG. 3 is a top plan view of a completed packaged computer disk that was produced utilizing the apparatus illustrated in FIG. 1.
FIG. 4 is a top plan view of a web of material depicting an alternative embodiment of the present invention prior to depositing the computer disk.
FIG. 5 is a top plan view of the web shown in FIG. 4 after the computer disk and transparent material have been deposited.
FIG. 6 illustrates a magazine with the packaged disk shown in FIG. 3 incorporated therein.
FIG. 7 illustrates the packaged disk of FIG. 3 incorporated into a gathered book.
FIG. 8 is a horizontal section view of the gathered book illustrated in FIG. 7.
FIG. 9 is a schematic perspective view of an alternative apparatus that could be used to practice the present invention.
FIG. 10 is a top plan view of a web of material illustrating the relative positioning of adhesive and a computer disk immediately after the computer disk has been deposited onto the web in accordance with the embodiment of FIG. 9.
FIG. 11 is top plan view of another embodiment of the present invention.
FIG. 12 illustrates a book block having the packaged compact disk of FIG. 11 incorporated therein.
DETAILED DESCRIPTION
FIG. 1 schematically illustrates a paper wrapper 10 having a pattern glue unit 12, a product feeder 14 and a cutter mechanism 16. Briefly, the paper wrapper 10 feeds a web 18 of paper from a roll 20 and toward the glue unit 12. Glue 22 is selectively deposited in a predetermined pattern on the web 18. Products 24 are successively fed from the product feeder 14 and onto the web 18 in spaced relation. Preferably, the products 24 are fed onto a non-glued portion of the web 18. The paper wrapper 10 then folds the web 18, one side at a time, until the web 18 is completely folded around the deposited product 24. Upon folding, the glued portions of the web 18 hold the web 18 in the folded condition. The folded web 18 is then cut into individual packages 26 by the cutter mechanism 16. Paper wrappers 10 of this type are commonly used to wrap paper (or other sheet material 54, such as plastic) around completed magazines. The paper wrapper 10 could, for example, be an MTR Enveloper available from Buhrs Zaandam of The Netherlands or Buhrs America of Eden Prairie, Minn.
The pattern glue unit 12 is positioned between the roll 20 and the product feeder 14. The glue unit 12 deposits glue 22 in a predetermined pattern onto the web 18. The type of glue used in the present invention can vary depending on the web 18 material and on the desired function. For example, if the web 18 is standard print paper, a hot melt glue could be used, such as product number 34-1123 sold by National Starch and Chemical Company of Chicago, Ill. Alternatively, a releasable glue, such as National Starch and Chemical Company product number 34-1123, could be used to make opening of the package 26 easier. A pattern glue unit 12 capable of performing the above-noted function is available as part of the above-described Buhrs Zaandam paper wrapper 10. If desired, the glue heads (not shown) of the glue unit 12 can be interchanged to customize the size and number of the glue beads.
The preferred glue pattern is illustrated in FIG. 2, and includes a plurality of small glue beads 28 arranged in such a manner that there is a centrally-located glueless area 30. It should be appreciated that the glue can be applied in any appropriate manner, such as in a bead, stitch, swirl or film. The centrally-located glueless area 30 provides a location for subsequently depositing the product 24. In this manner, no glue will get on the product 24. However, it is noted that the glue beads 28 substantially completely surround the entire perimeter of the glueless area 30, the benefits of which is described below. The glue pattern is generally confined to a middle portion 32 of the web 18 defined by the locations of first and second fold lines 34,36 that illustrate the location that the web 18 will be folded by the paper wrapper 10. The portion of the web 18 to the left of the first fold line will be called the left portion 38, and the portion of the web 18 to the right of the second fold line will be called the right portion 40 (i.e., as viewed in FIG. 2). In addition to the glue in the middle portion 32, glue is also applied to the outer edge of the right portion 40. This glue holds the right portion 40 folded onto the left portion 38 after the folding operation, as described below in more detail.
After glue is deposited onto the web 18, the product feeder 14 deposits a product 24 into the glueless area 30 of the glue pattern. In the illustrated embodiment, the product 24 is a CD-ROM. However, it should be appreciated that the present invention could package other types of products, such as products that have protected opposing surfaces or protected edges. That is, the present invention is particularly applicable to products that have surfaces that could be damaged by gluing, stitching or stapling the product to a signature or card insert in a conventional manner or to products that have edges that could be damaged due to impact. For example, products such as laser disks, phonorecords, computer disks (i.e., CD-ROMs, floppy disks, hard disks, etc.), or any other appropriate product that has protected opposing surfaces could be packaged by the present invention.
The product feeder 14 can be any appropriate apparatus that feeds products 24 (commonly referred to as a "feeder pocket" in the printing industry). For example, a suitable product feeder 14 is called a Pick and Placer, available from Minnesota Automation of Crosby, Minn. Alternatively, instead of feeding directly to the web, the product feeder can feed to a conveyor, and the conveyor can feed to the web.
After depositing the product 24, the left portion 38 of the web 18 is folded by moving the left portion 38 on top of the middle portion 32, thereby covering the entire product 24 and most of the middle portion 32. The fold location, illustrated by the first fold line 34, is intentionally spaced from the product 24, thereby defining a gap 42 between the fold location and the product 24. In addition, the glue pattern is positioned so that a portion of the glue is within the gap 42. In this manner, the left and middle portions of the web 18 will be secured together in the gap 42, thereby forming a secured gap 42 and preventing the product 24 from coming into contact with the fold location. Such a design is beneficial in that it protects the disk from damage in the event that the package 26 is dropped onto a hard surface. That is, if there was no secured gap between the product 24 and the fold location, and if the package 26 was dropped on that folded edge, the product 24 could be severely impacted and damaged by the hard surface. If, on the other hand, there is a secured gap 42 between the product 24 and the hard surface, the product 24 will be somewhat isolated from the hard surface, and the impact will be less severe.
In addition to providing the above-described secured gap 42 between the product 24 and the fold line, the glue pattern is also designed to provide similar secured gaps between the product 24 and the other sides of the package 26. That is, substantially the entire perimeter of the product 24 is surrounded by a secured gap produced by sealing the left portion 38 to the middle portion 32. This design maintains the product 24 spaced from the edges of the package 26, thereby reducing the likelihood of damage to the product 24 in the event that the package 26 is struck on its edge by a hard surface, as described above.
After the left portion 38 has been folded, the right portion 40 is folded over the middle and left portions. In the illustrated embodiment, the right portion 40 does not extend far enough to cover any part of the product 24. The right portion 40 is secured to the left portion 38 by the glue that was previously applied to the right portion 40 by the pattern glue unit 12.
After the folding operation, the web 18 is cut into separate packages 26. This operation is performed by the cutter mechanism 16 that is available with the above-described paper wrapper 10 from Buhrs Zaandam. The cutter mechanism 16 has been modified so that it also forms a perforation line 44 simultaneously with the cutting operation. The illustrated perforation line 44 is formed adjacent and parallel to the leading edge 46 of each package 26. The edge portion 48 of each package 26 between the perforation line 44 and the leading edge 46 is designed to be secured to a printed publication, such as a periodical, catalog or magazine. In this regard, the perforation line 44 facilitates removal of the packages 26 from the printed publication (i.e., by tearing at the perforation line 44).
The width of the edge portion 48 between the perforation line 44 and the leading edge 46 can vary depending on the desired subsequent used of the package 26. For example, if the package 26 will be incorporated into a saddle-stitched publication, a wider edge portion 48 (e.g., about three to four inches wider) will be needed to provide a place to form a fold that will act as the binding during the saddle stitching operation. If, on the other hand, the package 26 will be placed in a perfectly bound publication, then the edge portion 48 can be relatively narrow (e.g., as illustrated), since no fold is required. In the illustrated embodiment, the width of the edge portion 48 (i.e., the distance between the perforation line 44 and the leading edge 46) is about 0.5 inches (12.7 mm).
In an alternative embodiment illustrated in FIG. 4, the packaged disk includes a transparent window 50 that allows text or other indicia on the product 24 to be viewed from the exterior of the package 26, thereby allowing identification of the product 24 without opening 52 of the package 26. Referring to FIGS. 5-6, the transparent window 50 is produced by forming (e.g., cutting) an opening 52 in the web in the area where the transparent window 50 is desired. In the illustrated embodiment, the opening 52 is formed in the center of the left portion 38 (FIG. 5) utilizing an appropriate cutting device. Formation of the window 50 can occur before or after the pattern glue operation, but preferably occurs before to avoid getting glue on the cutting blades. The pattern glue operation deposits glue 22 around the opening 52, in addition to the above-described glue locations. The glue 22 around the opening 52 facilitates securement of transparent material 54 over the opening 52, as shown in FIG. 6. The transparent material 54 can be deposited at the same time as the product 24, if desired, but could also be deposited at any time after the glue operation and before the folding operation. Instead of using glue on the web, the transparent material 54 can be provided with adhesive ahead of time.
The web can also be provided with printing on the side that forms the exterior of the package. For example, printing can be provided on the exterior side of the left portion so that the text is visible to the consumer. The printing can be text and/or designs that provide aesthetic and/or identification functions. For example, the printing could be text that identifies the product. Such printing can be performed before, during or after the packaging operation. Also, the printing can be used with or without the above-described transparent window.
The above-described designs are specifically designed to be incorporated into a printed publication 56, such as a magazine. The package 26 can be fed into a standard gatherer during the book-forming process. For example, the packaged disk can be fed to a chain-type gatherer, a rotary gatherer, or a pusher-type gatherer with the perforated edge lined up with the binding. During the gathering process, signatures 58 are continually pushed at the foot, thereby forcing the foot of each signature 58, and the foot 60 of the package 26, to be aligned with each other. A cover 62 can then be applied to binding 64 of the gathered signatures, thereby resulting in the perfect-bound gathered book illustrated in FIGS. 7 and 8. In the illustrated embodiment, the foot 60 of the package 26 would correspond with one of the two folded edges. After the gathered book is complete, the book is trimmed/cut along the three non-binding sides. The result is that the foot 60 of the package 26 (which corresponds with a folded edge) will likely be trimmed slightly. The provision of the secured gap 42 between the product and the folded edge facilitates such trimming. That is, without the secured gap 42, the product itself could be trimmed and/or the folded edge could be trimmed, thereby allowing the product to fall out of the package 26.
FIGS. 9 and 10 schematically illustrate an alternative embodiment of the present invention. FIG. 9 illustrates a paper wrapper 110 having a pattern glue unit 112, and a product feeder 114. As with the embodiment of FIG. 1, the paper wrapper 110 feeds a web 118 of paper from a roll 120 and toward the glue unit 112. Glue 122 is selectively deposited in a predetermined pattern on the web 118. Products 124 are successively fed from the product feeder 114 and onto the web 118 in spaced relation. Preferably, the products 124 are fed onto a non-glued portion of the web 118. The paper wrapper 110 then folds the web 118, one panel at a time, until the web 118 is completely folded around the deposited product 124. Upon folding, the glued portions of the web 118 hold the left portion in the folded condition. The right portion is folded but is not secured to the glued portions. The folded web 18 is then cut into individual packages 126 by a cutter mechanism (not shown in FIG. 9). Specifics regarding the wrapper 110, the glue unit and the product feeder are set forth above in describing the embodiment of FIG. 1.
The corresponding glue pattern is illustrated in FIG. 10, and includes a plurality of short glue beads 128 and long glue beads 129 arranged in such a manner that there is a centrally-located glueless area 130. The centrally-located glueless area 130 provides a location for subsequently depositing the product 124. In this manner, no glue will get on the product 124. However, it is noted that the glue beads 128,129 substantially completely surround the entire perimeter of the glueless area 130. The glue pattern is generally confined to a middle portion 132 of the web 118 defined by the locations of first and second fold lines 134,136 that illustrate the location that the web 118 will be folded by the paper wrapper 110. The portion of the web 118 to the left of the first fold line 134 will be called the left portion 138, and the portion of the web 118 to the right of the second fold line will be called the right portion 140 (i.e., as viewed in FIG. 10).
After the completed package 126 has been created, it can be incorporated into a printed product, such as a magazine. More specifically, a stack of packages 126 can be positioned into a signature feeder on a binding line. The packages 126 can be oriented such that, when fed onto a gathering chain (i.e., binding vane), the right portion 140 will be placed on one side of the chain and the left portion 138 will be placed on the other side of the chain. In this manner, the package 126 will be supported on the chain so that standard gathering and binding operations can be performed. A signature feeder is disclosed in U.S. Pat. No. 5,100,116, which is incorporated herein by reference in its entirety.
FIG. 11 illustrates another alternative design. The illustrated design is similar to the one illustrated in FIG. 10, except that no long glue beads are provided in the middle portion 150, and a glue bead 152 is provided on the left portion 154. In addition, perforations 156 are formed in the middle portion 150 and right portion 158, an equal distance on either side of one of the fold lines 160. The perforations 156 are formed before the folding operation. In this manner, the perforations 156 will be substantially aligned with each other after the folding operation.
The package of FIG. 11 is produced by folding the right portion 158 over the middle portion 150, and the left portion 154 over the right portion 158. Both the left portion 154 and the right portion 158 are held down by glue.
The resulting package can be utilized in a perfect binding procedure with one of the glued edges 162 used as the binding edge 164 (see FIG. 12). With the perforations in the illustrated fashion, the disk 164 can be easily removed from the package. Furthermore, the tear-away strip 166 will stay secured in the printed publication even after the disk is removed.
If desired, the packaged disk can be provided with personalization in the form of the recipient's name, a message, graphics, an access code or other suitable indicia. This can be done, for example, using ink jet printers positioned to print at desired locations. If personalization is desired on the disk, then the printer can be positioned at the product feeder to print on the disk immediately before it is deposited onto the web, or above the web to print on the disk after the disk has been deposited onto the web. The printing can also occur on the web before the disk is deposited and at the location where the disk will be deposited. In this manner, the personalization will be hidden by the disk. Printing on the web is advantageous in that, if an error requires scrapping of a group of packaged disks, the disks can be salvaged and re-used since they are not personalized. Instead of printing, the personalization can occur by adding or securing a label (e.g., a sticker or some other personalized indicia) to the packaged disk. Personalization of printed materials using ink jet printing is disclosed in U.S. Pat. Nos. 5,029,830 and 5,100,116.
In order to simplify the process, the apparatus that produces the packaged disks should be incorporated into the gathering and binding apparatus. More specifically, if personalization will be added to the packaged disks while they are being produced, then it is important to maintain their order relative to the binding apparatus so that each personalized packaged disk will be matched up with the appropriate signatures to form a printed publication. This can be accomplished by positioning the output of the packaging apparatus to feed to the input of a pocket feeder (or other appropriate machine) on the gathering and binding apparatus. In this manner, the packaging apparatus will be integrated into the gathering and binding apparatus, and will continuously feed packaged and personalized disks to the gathering and binding apparatus. That is, the packaged disks may be fed continuously in their packaged order on a conveyor in a separated or imbricated stream, but the disks are not removed and taken out of order between the packaging and gathering steps.
The foregoing description of the present invention has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit the invention to the form disclosed herein. Consequently, variations and modifications commensurate with the above teachings, and the skill or knowledge of the relevant art, are within the scope of the present invention. The embodiments described herein are further intended to explain best modes known for practicing the invention and to enable others skilled in the art to utilize the invention in such, or other, embodiments and with various modifications required by the particular applications or uses of the present invention. It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art. | A method of producing a printed product having a computer disk incorporated therein, including the steps of providing a sheet of material, placing personalized indicia onto either the disk or the sheet of material, depositing the disk onto the sheet of material, folding the sheet of material over the disk to produce a package, gathering the package with a signature to produce a book block, and binding the book block to produce a printed product. The placing step can include the step of printing or the step of adding a label to either the disk or the sheet of material. The depositing step can include the step of positioning the disk over the personalized indicia such that the disk covers the personalized indicia. The placing step can occur either before or after the depositing step. | 1 |
[0003] This application claims priority under 35 U.S.C. § 119 to British application number 0324203.9, filed 15 Oct. 2003, the entirety of which is incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] This invention relates to a turbine rotor blade for a gas turbine engine, to a turbine rotor incorporating such blades, and to a gas turbine engine comprising such a rotor.
[0006] 2. Brief Description of the Related Art
[0007] The turbine of a gas turbine engine depends for its operation on the transfer of energy between the combustion gases and turbine. The losses which prevent the turbine being totally efficient are due in part to leakage flow of working fluid over the turbine blade rotor tips.
[0008] In turbines with unshrouded rotor blades, a portion of the working fluid flowing through the turbine tends to migrate from the pressure surface to the suction surface of the blade aerofoil through the gap between its tip and the stationary shroud or casing. This leakage occurs because of a pressure difference that exists between the pressure and suction sides of the aerofoil. The leakage flow also causes flow disturbances to be set up over a large portion of the span of the aerofoil, which also leads to losses in the efficiency of the turbine.
[0009] By controlling the leakage flow of air or gas across the tips of the blades it is possible to increase the efficiency of each rotor stage. One solution is to apply a shroud to the rotor tip. When the rotor blades are assembled together in the disc that carries them, these shrouds form a continuous ring that prevents the leakage flow from the aerofoil pressure to suction side at the tip. There is still an axial leakage through the gap between the casing and the rotating shroud, but the penalties in terms of aerodynamic losses are much reduced—often helped by the inclusion of a form of labyrinth seal on the shroud top.
[0010] However, the rotating shroud has a large weight penalty. As a result, the aerofoil blade speed may be constrained, to achieve acceptable blade stresses. This, though, will have the effect of increasing the aerodynamic loading that also results in reduced efficiency, negating some of the benefit of the shroud.
[0011] The use of a shroud ring is made more difficult if the turbine blades also operate at very high temperatures, desirable in helping to achieve high thermal efficiencies. These temperatures are limited by the turbine vane and blade materials. Cooling of these components is necessary to achieve acceptable component life, which is a function of the material temperature, stresses and material properties.
[0012] A large number of cooling systems are now applied to modern gas turbine blades. Such cooling systems are described for instance in Cohen H, Rogers G F C, Saravanamuttoo H I H, 1981, “Gas Turbine Theory”, p.232-235, Longman, and Rolls-Royce plc, 1986, “The Jet Engine”, p.86-88, Renault Printing Co Ltd. The more cooling that is provided, the lower the resulting material temperatures, and thus the higher the blade stresses allowable for a given component life. Cooling is achieved using relatively cool fluid bled from the upstream compressor system, bypassing the combustion chamber between the last compressor and first turbine. This air is introduced into the turbine blades where cooling is effected by a combination of internal convective cooling and external cooling. However, this cooling comes at a penalty. Its use penalises the overall efficiency of the machine, and as a result the turbine designer tries to minimise the quantity of cooling air used. All of these design constraints often leads to rotor blades of first staged turbines being shroudless—the extra weight and thus higher stresses caused by a shroud ring simply cannot be accommodated. However, ways of reducing the high aerodynamic penalty of the resulting tip leakage flow continue to be sought.
[0013] U.S. Pat. No. 5,525,038 discloses a blade aerofoil design intended to reduce tip leakage losses. In that document, the tip region of the suction side of the aerofoil has a bowed surface with an arcuate shape. The arcuate shape of the bowed surface has progressively increasing curvature toward the tip of the rotor blade, so that a radial component of a normal to the suction side bowed surface becomes progressively larger toward the tip. It is to be noted that the aerofoil has a bowed surface in the tip region extending chordally all the way from the leading edge to the trailing edge. In addition, all the leans of the tip described, whether tangential and/or axial, are applied to the whole of the tip region.
[0014] A particular area of the blade that requires attention in its design is the trailing edge. Preferably, this is kept thin to minimise aerodynamic losses, but as a result it is difficult to cool, and tensile stresses have to be minimised. Cooling is achieved by films of air ejected upstream of the trailing edge on to the aerofoil surfaces, and by drilling cooling holes into the trailing edge fed from larger radial passages within the main body of the aerofoil. The aerofoil disclosed in U.S. Pat. No. 5,525,038 thus has some disadvantages: firstly, the curved trailing edge cannot easily have cooling holes machined into it. Ideally, this is done in one operation to minimise cost, but this requires all holes to lie in the same plane, i.e. the trailing edges of the aerofoil sections making up the blade have all to lie in one plane. A curved trailing edge (with a progressively increasing curvature) will require holes to be machined in multiple operations, incurring significant extra cost. Secondly, the leant tip will give rise to additional bending stresses in the blade. In the main body of the blades these can usually be accommodated by changes in the detailed design, such as increasing wall thickness locally. However, this cannot be done in the trailing edge region, there will simply be higher stresses in it. This will result either in a reduced life of the component, or require additional cooling, which will impair the performance of the engine.
SUMMARY OF THE INVENTION
[0015] Accordingly, the technical problem to be solved by the present invention is to provide a turbine rotor blade for a gas turbine engine which avoids the drawbacks of the cited prior art but still provides reduced tip leakage losses. Further, the manufacturing costs should be kept low and the reliability high.
[0016] An exemplary embodiment in accordance with principles of the present invention provides a rotor blade for a gas turbine engine, the blade comprising a blade root and an aerofoil projecting therefrom, the aerofoil having a leading edge and a trailing edge, a generally concave pressure surface and a generally convex suction surface, and is characterised in that the aerofoil shape varies in section along the length thereof such that:
the chord-wise convex curvature of the rear suction surface decreases towards the tip of the blade; the convex curvature of the early to mid suction surface increases towards the tip; the stagger of the aerofoil section increases towards the tip; and the trailing edge is a straight line.
[0021] The terms “concave” and “convex” refer in this context to the chordwise direction. Preferably, the increase in stagger is such as to give rise to chord-wise convex curvature on the pressure surface. This has the aerodynamic result that velocities on the pressure surface are increased, reducing the local static pressure which drives the over-tip leakage, thus reducing the leakage further.
[0022] The line of the trailing edge is advantageously radial, but it may be leant at some radial and/or tangential angle, depending on the aerodynamic and mechanical details of the design.
[0023] The chord-wise convex curvature of the rear suction surface may be eliminated in the tip section to give a flat back surface, or it may even be reversed so as to be concave.
[0024] The lower part of the aerofoil will exemplarily have a minimum radial extent of 40% and a maximum radial extent of 80% of the span. The tip section is preferably geometrically and aerodynamically blended smoothly into the lower portion of the aerofoil. The blending of the aerofoil between the tip section and the lower portion will preferably be such as to evenly redistribute the aerodynamic loading radially away from the tip.
[0025] The trailing edge regions of the aerofoil sections are preferably shaped so as to be similar in 2-D plan view, such that a row of chord-wise running cooling holes provided in the trailing edge will lie in a radial geometric plane, enabling them to be machined in a single operation.
[0026] The increased stagger of the aerofoil tip section, relative to the lower, datum portion, will cause the front/mid portion of the aerofoil tip region to be tangentially leant, in a direction towards the suction side. Unlike the arrangements disclosed in U.S. Pat. No. 5,525,038, the leaning is confined to a limited part of the tip, while the trailing edge is kept straight. Thus, in the tip region only the front/mid portion of the suction surface may be concave in the radial direction, and only the front portion of the pressure surface may be convex in the radial direction.
[0027] The invention also provides a turbine rotor for a gas turbine engine, comprising a plurality of turbine blades in accordance with the invention. The invention further provides a gas turbine engine including the turbine rotor of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] A more complete appreciation of the invention and of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings. In the drawings:
[0029] FIG. 1 is a plot of Mach number distributions (normalised to exit) for the mid-span aerofoil sections of two rotor blades according to the prior art;
[0030] FIG. 2 is an illustration of the mid-span section profile shapes for the blades plotted in FIG. 1 ;
[0031] FIGS. 3 and 4 are isometric views of the full aerofoil shapes of the blades of FIGS. 1 and 2 ;
[0032] FIG. 5 is a plot of percentage loss of turbine stage efficiency against tip clearance or gap as a percentage of blade span, produced by Computational Fluid Dynamics (CFD);
[0033] FIG. 6 is a plot of tip Mach number distribution, as calculated by CFD, for the aerofoils shown in FIGS. 3 and 4 ;
[0034] FIG. 7 is an isometric view of two high lift aerofoils which have been restacked to give a lean;
[0035] FIG. 8 repeats the plot of FIG. 5 , but with comparative results for the aerofoil of FIG. 7 included;
[0036] FIG. 9 is a plot of the calculated Mach number distribution for the aerofoils of FIGS. 3 and 7 at 90% of the span;
[0037] FIG. 10 is a corresponding plot at mid-span;
[0038] FIG. 11 is a plot of calculated 2 -D Mach number distributions for the conventional and redesigned blade illustrated in FIG. 12 ;
[0039] FIG. 12 is a sectional view comparing a conventional aft-loaded aerofoil tip section with a corresponding section of a blade in accordance with the invention;
[0040] FIG. 13 is an isometric view from the front of rotor blades in accordance with an exemplary embodiment of the invention;
[0041] FIG. 14 is a plot of tip Mach number distribution, as calculated by CFD, for the aerofoil in accordance with the invention;
[0042] FIG. 15 is a comparison of CFD calculated rotor loss against tip gap; and
[0043] FIG. 16 is a plan view of the rotor blade of FIG. 13 showing successive aerofoil sections equally-spaced radially at 5% of span.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0044] Before describing in detail the geometric configuration of a turbine rotor blade in accordance with the invention, it is useful to describe how the configuration operates, and in particular how it affects the turbine rotor aerodynamics. First the basic turbine aerodynamics will be considered, then the benefits of aerodynamically off-loading the tip, and finally the detail of the invention will be described.
[0045] The turbine blade of the invention is of a “high lift” aerodynamic design, and FIG. 1 is a graph comparing the Mach number distributions (normalized to exit) for the mid-span aerofoil sections of two rotor blades that have the same axial chord and the same inlet and exit flow conditions as each other. The two aerofoils are differentiated as follows:
[0046] A conventional (low) lift aerofoil characterized by only a small diffusion of the flow from the Mach number point on the late suction surface to the trailing edge (known as “back surface diffusion”).
[0047] A high lift aerofoil, carrying approximately 36% more lift than a conventional profile, achieved by increasing the pitch of the profiles in the same proportion to give a reduction in aerofoil numbers of about 30%. The back surface diffusion is now much larger, and the peak Mach number has significantly increased.
[0048] FIG. 2 compares the mid-span section profile shapes. The full aerofoil shapes of the two blades are shown in isometric view in FIG. 3 (conventional) and FIG. 4 (high lift). The increased pitch of the high lift blading is clear. Both aerofoils clearly have convex curved suction surfaces 1 (in the chord-wise direction), with the locations of the peak Mach number point coinciding with a local maximum in the surface curvature. Each blade has concave pressure surfaces 2 , a root end 3 and a tip 4 . Both aerofoils are radially stacked in the same way on a straight line 5 through the centres of the trailing edge circles.
[0049] Calculations of the flow around these two aerofoils have been performed using Computational Fluid Dynamics (CFD) over a range of tip clearances. The results, in the form of predicted rotor loss (expressed as a percentage of turbine stage efficiency) against tip gap (expressed as a percentage of rotor span) are shown in FIG. 5 . It should be noted that these predictions would not normally be used to give absolute values of efficiency, but may still demonstrate qualitative differences between different geometries.
[0050] ASME 96-TA-13, November 1998, “Reduction of Tip Clearance Losses Through 3-D Airfoil Designs”, Staubach J B, Sharma O P, Stetson G M (reference 3) gives a typical value for the over-tip leakage loss exchange rate of a turbine rotor blade of about numeral 2% of stage efficiency for 1% gap/span. The values shown in FIG. 5 for the conventional blade are slightly less than this, confirming that CFD is best used for qualitative predictions, rather than absolute accuracy.
[0051] FIG. 5 also shows that at zero tip gap, the two aerofoils have almost the same loss (given the accuracy of the CFD code used). However, it is clear that the high lift aerofoil has significantly higher tip leakage losses than the conventional one, at any given tip gap. The reason for this can be seen in FIG. 6 . This compares the calculated Mach number distributions at 90% span, near the tip, for the conventional and high lift aerofoils respectively. The much higher aerodynamic loading of the high lift aerofoil gives rise to higher tip leakage and higher mixing losses, due to the higher gas stream velocities on the suction side.
[0052] Reference 3 shows how leaning the blade tip, as illustrated in U.S. Pat. No. 5,525,038, reduces the tip leakage loss. To demonstrate this, the high lift aerofoil has been stacked as described in Reference 3, and the resulting flow field calculated again by CFD. FIG. 7 shows an isometric view of the restacked, high lift aerofoil. The lean is purely tangential, beginning at about 60% span, the curve of the stacking axis being parabolic in shape with the highest angle to the vertical (40°) being at the tip.
[0053] FIG. 8 repeats the plot of FIG. 5 (rotor loss as a percentage of the stage efficiency versus percentage gap/span) but now with the leant rotor tip results added. The tip leakage loss is reduced, but the zero gap loss is higher, which means that it is only really beneficial at larger tip gaps.
[0054] The reasons for this can be understood by comparing the calculated aerofoil Mach number distributions for the straight and leant tip aerofoils at 90% span ( FIG. 9 ), and at mid-span ( FIG. 10 ). FIG. 9 shows how the tip lean has off-loaded the need suction surface of the tip section; this results in reduced tip leakage loss. However, the loading has been redistributed down the span, as can be seen at mid-span in FIG. 10 . The higher surface velocities here result in increased profile (wetted area) losses, and although these are somewhat reduced near the tip, the overall effect is an increase in loss at zero gap.
[0055] FIG. 9 is also noteworthy in that the tip lean is shown to only off-load the early/mid part of the aerofoil suction surface. This is one of the drawbacks of simply leaning the aerofoil tip whilst leaving the aerofoil shapes unchanged. The velocity distribution on the late suction surface is largely unaffected, which limits the reduction in the aerodynamic loading at the tip that can be achieved.
[0056] Referring now to FIG. 12 , in accordance with the invention, the 2-D aerofoil section at the tip is redesigned to significantly change the velocity distribution. Instead of being aft-loaded, the loading is moved forward, when analyzed as simply a 2-D aerodynamic section. This can be seen in FIG. 11 , which compares the calculated 2-D Mach number distributions for the original and redesigned tip sections at 90 percent span. The redesigned profile shown is an extreme example, where the loading has been moved to the front of the aerofoil. More usually, the loading will be moved to the mid region. The design of the aerofoils in the lower portion of the blade, radially from the hub to, typically, around mid-span remains strongly aft-loaded. The change in the 2-D lift distribution of the tip section is effected by reducing the chord-wise convex curvature on the late suction surface and increasing this curvature in the front/mid region. It is possible that the late suction surface can become flat or even concave, to minimize the lift locally. As a result of the changes in the surface curvature of the tip section, the stagger of the section increases. Stagger is here defined as the angle between the turbine centre line and a line drawn through the centers of the leading and trailing edge circles of the aerofoil. Thus, the front part of the redesigned aerofoil is moved in the direction of the suction surface, relative to the original design, when viewed with the trailing edges coincident, as shown in FIG. 12 .
[0057] The redesigned tip section, with lift moved forward, is now stacked with the aft-loaded aerofoils in the lower portion to produce the aerofoil shown in isometric view in FIG. 13 . The stack is on a radial line through the trailing edge, as with the original high lift aerofoil. It can be seen that with the radially straight trailing edge 5 , the progressive increase in aerofoil stagger up the span results in local tip lean in the forward part of the aerofoil. This local tip lean has the effect of redistributing the aerodynamic loading in the front part of the aerofoil radially, from the tip downwards to the lower aerofoil sections. It should be remembered that the 2-D design of the tip section deliberately moved the lift forward to the mid/front regions of the aerofoil, where the local lean has the most effect. The redistribution of lift radially inwards from the tip region is similar to that caused by leaning the whole tip, and results in increased lift on the lower aerofoil sections. Since this extra lift is in the front/mid part of the suction surface, it can be seen that designing these lower sections to be strongly aft-loaded will in part compensate for this.
[0058] The resulting tip Mach number distribution, as calculated by CFD, is shown in FIG. 14 compared with that of the original high lift design. It will be seen that the Mach numbers along most of the suction surface have been reduced, compared with the unmodified aerofoil. This will result in lower tip leakage flow and reduced mixing. The Mach numbers on the late pressure surface have been raised, that is the local static pressures have been reduced. This will also have the effect of reducing tip leakage. There is a small increase in lift on the suction surface, just after the leading edge, for the redesigned profile. This is because an extreme forward loaded design has been shown as an example here. However, this is not an intrinsic feature of the invention. Comparison of FIG. 11 with FIG. 14 shows that the high lift on the early suction surface in the 2-D design has been removed (radially redistributed) by 3-D effects, as intended.
[0059] FIG. 15 plots the variation of CFD predicted rotor loss with tip gap, repeating the results of FIG. 8 , but now with the results from the redesigned tip added. It can be seen from the Figure that at zero tip gap, the loss is higher than that of the unmodified high lift aerofoil, and very similar to that of the fully leant tip. The reasons for the loss being higher than the original profile at zero tip gap are much the same as for the fully leant tip. The loss due to over tip leakage is much reduced compare to the unmodified high lift aerofoil. The improvement is better than the fully leant aerofoil analyzed here. Further, for large gaps (two percent of span), the loss is close to that of the low lift aerofoil. The increased loss due to high lift has almost been eliminated.
[0060] FIG. 16 shows an overlay of some of the 2-D aerofoil sections, viewed radially from above. It can be seen that, in the trailing edge region, the aerofoil shapes are almost coincident. This means that machining of trailing edge cooling holes can easily be done in a single operation, minimizing cost of manufacture, and there should be no additional bending stresses in this critical trailing edge region.
[0061] Reference Signs
1 suction surface 2 pressure surface 3 blade root 4 tip 5 trailing edge
[0067] While the invention has been described in detail with reference to exemplary embodiments thereof, it will be apparent to one skilled in the art that various changes can be made, and equivalents employed, without departing from the scope of the invention. Each of the aforementioned documents is incorporated by reference herein in its entirety. | A rotor blade for a gas turbine engine includes a blade root ( 3 ) and an aerofoil projecting therefrom, the aerofoil having a leading edge and a trailing edge ( 5 ), a generally concave pressure surface ( 2 ) and a generally convex suction surface ( 1 ). The aerofoil shape of the blade varies in section along the length thereof such that:
the chord-wise convex curvature of the rear suction surface decreases towards the tip ( 4 ) of the blade; the convex curvature of the early to mid suction surface increases towards the tip; the stagger of the aerofoil section increases towards the tip; and
the trailing edge ( 5 ) is a straight line. | 5 |
BACKGROUND OF THE INVENTION
This invention relates generally to portable air blowers often used when drying carpets. More particularly, this invention relates to an air blower having motor driven fan means internally supported by an improved mounting arrangement that absorbs impact-created shock forces and incidental vibration.
Portable air blowers are well known and typically include an electric motor and a blower wheel or fan, which are contained within a housing having an air intake vent and an air exhaust vent. Exemplary of prior devices is the squirrel cage fan air blower, which has drawbacks in common with other prior air blowers. More particularly the squirrel cage fan, as originally developed many years ago, was designed for stationary use only. The squirrel cage fan was not designed for use in portable equipment and, consequently, it was not constructed to withstand the abuse that portable equipment is often subjected to. This is apparent from the structure of a squirrel cage fan, in which the fan is supported by a weak, centrally located, single mounting hub that is insufficient to withstand multi-directional shock forces encountered when portable equipment is dropped or roughly handled while in a running mode. Historically, the life expectancy of squirrel cage fan air blowers has been relatively short.
The problems associated with prior air blowers have arisen due to the very nature of such blowers. In particular, in order to move a high volume of air, the blowers are designed to rotate a large fan or blower wheel as fast as possible within the blower housing. This requires that the motor and the blower wheel be precisely aligned within the housing so as not to create unwanted and possibly destructive vibration.
Portable air blowers are often subjected to rough handling during transportation and in use. Prior designs, characterized by an internal mounting arrangement which rigidly supports the blower means within the housing, attempted to protect the internal air blower components by providing stiffly resilient housings capable of absorbing some impact-created forces. It has been found that, in spite of all previous precautions, the internal components of prior portable air blowers invariably eventually become tweaked or misaligned as they are repeatedly subjected to jarring, impact-created shock forces. Such misalignment occurs partly due to the rigid nature of the mounting arrangement of the motor and blower wheel within the housing, which often precludes the absorption or damping of these impact-created shock forces by flexion.
The result of a misorientation of the motor and/or blower wheel within the housing is the creation of undesirable vibration within the air blower. Vibration within a portable air dryer is very undesirable because it can cause the blower to bounce or walk across a hard surface. As the vibration becomes progressively worse, mechanical parts of the blower begin to wear out prematurely, which ultimately renders the air blower unusable.
There exists, therefore, a significant need for a portable air blower having means for mounting the motor and the blower wheel within the housing in a manner permitting limited and temporary flexion of the motor and the blower wheel with respect to the housing when the air blower is subjected to impact-created shock forces. Additionally, a portable air blower having such a mounting arrangement is needed which returns the motor and the blower wheel to a preferred position within the housing immediately following and in the absence of shock forces. Such an improved mounting arrangement should be compatible with standard portable air blower design and result in no degradation in the capability of such air blowers. Further, a novel mounting arrangement is needed which is relatively inexpensive, durable and reliable. An arrangement utilizing similar parts for mounting each end of the blower means, or motor and blower wheel assembly, within the housing would be preferred. The present invention fulfills these needs and provides further related advantages.
SUMMARY OF THE INVENTION
The present invention resides in a vibration and shock damping portable air blower which satisfies the needs set forth above. The air blower comprises, generally, a flexibly resilient housing having separate air intake means and air exhaust means, and blower means within the housing for drawing air into the housing through the air intake means and blowing the air out of the housing through the air exhaust means. First blower support means are provided for mounting a first end of the blower means to a first end of the housing in a manner permitting resilient flexion of the blower means with respect to the first housing end. Similarly, second blower support means are provided for mounting a second end of the blower means to a second end of the housing in a manner permitting resilient flexion of the blower means with respect to the second housing end. The first and second blower support means cooperatively support the blower means within the housing in a manner permitting limited and temporary flexion of the blower means with respect to the housing when the air blower is subjected to impact-created shock forces.
In a preferred form of the invention, the flexibly resilient housing includes a first end, a second end, air intake means situated adjacent to both the first and second ends, and a separate air exhaust means. The blower means includes a motor having a motor body and a rotatable shaft extending therefrom, and a generally cylindrical fan having a plurality of blades arranged for rotation about the motor. The cylindrical fan includes a central web portion having a blower wheel support block which is placed over and anchored to a portion of the motor shaft. When the blower wheel support block is fixed to the motor shaft, rotation of the shaft causes a like rotation of the fan.
A rigid motor mounting bracket is fixed to an end of the motor housing opposite the motor shaft. Means are provided for attaching the motor mounting bracket to the housing first end in a manner permitting resilient flexion of the motor with respect to the first housing end. The motor mounting bracket attaching means includes a plurality of first shock mounts which each comprises a bolt, resilient elastomeric grommet means interposed between the bolt and a portion of the motor mounting bracket, and a nut for securing the bolt to the housing first end.
Means are also provided for supporting the motor shaft, which motor shaft supporting means cooperates with the motor mounting bracket attaching means to support the blower means within the housing in a manner permitting limited and temporary flexion of the blower means with respect to the housing when the air blower is subjected to impact-created shock forces. The motor shaft supporting means includes a flexibly resilient support bracket having a head located generally adjacent to an end of the motor shaft, and a plurality of resiliently flexible support legs which extend from the bracket head in a pyramid-like configuration toward the housing second end. The support legs are each attached to the housing second end by a respective second shock mount which includes a bolt, a resilient elastomeric grommet means interposed between the bolt and a portion of the respective support leg, and a nut for securing the bolt to the housing second end.
A self-aligning bearing is situated on the bracket head for supporting the end of the motor shaft in a manner permitting rotation thereof relative to the motor shaft supporting means. The self-aligning bearing provides a release for stress and bending forces upon the motor shaft during multi-directional non-parallel flexing of the support legs. In this arrangement, radial deflection of the motor shaft is permitted to absorb energy and cushion the blower means.
This structure permits the blower means within the housing to flex in five distinct ways in response to impact-created shock forces. More particularly, due to the flexibly resilient nature of the housing, the bolt of each first shock mount is permitted to move with respect to its normal orientation by flexion of the housing. Secondly, the motor mounting bracket is permitted to flex, via the grommet means, with respect to the first shock mount bolts. Thus, the attachment between the motor and the housing is provided with two primary means of flexion. At the other end of the housing the bolts of the second shock mounts are similarly permitted to move or flex by movement or flexion of the housing itself. The bolts of both the first and second shock mounts pivot in any direction in a controlled full floating manner within the grommet means and then return to a normal orientation, thereby functioning as a torsion arm system that absorbs kinetic energy. The resiliently flexible support legs flex with respect to the second shock mounts via the grommet means provided therein. This is similar to the arrangement provided at the first end of the housing. In addition, however, the flexibly resilient support bracket is constructed to inherently provide further flexion in response to impact-created shock forces.
Other features and advantages of the present invention will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate the invention. In such drawings:
FIG. 1 is a perspective view of a vibration and shock damping air blower embodying the invention;
FIG. 2 is an exploded assembly view of the air blower shown in FIG. 1, illustrating a housing for the air blower and its internal components;
FIG. 3 is an enlarged, fragmented cross-sectional view taken generally on line 3--3 of FIG. 1, illustrating the assembled configuration of parts within the air blower housing;
FIG. 4 is an enlarged, fragmented and partially cross-sectional view taken generally of the area designated by the circle 4 in FIG. 3, illustrating the manner in which a second shock mount attaches a motor shaft support bracket to the housing, and also showing the normal configuration of a shock mount in the absence of shock forces;
FIG. 5 is an enlarged, fragmented and partially cross-sectional view taken generally of the area designated by the circle 5 in FIG. 3, illustrating the manner in which a first shock mount attaches a motor mounting bracket to the housing;
FIG. 6 is another illustration of the second shock mount and support bracket of FIG. 4, showing how the configuration of the second shock mount will change to absorb side-to-side movement of the support bracket;
FIG. 7 is another illustration similar to FIGS. 4 and 6, showing how the configuration of the second shock mount changes as it absorbs downward movement of the support bracket;
FIG. 8 is an additional illustration similar to FIGS. 4, 6 and 7, showing how the configuration of the second shock mount changes as it absorbs upward movement of the support bracket; and
FIG. 9 is still another illustration similar to FIGS. 4, and 6-8, showing how the configuration of the second shock mount changes as it absorbs angular movement of the support bracket.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in the drawings for purposes of illustration, the present invention is concerned with a vibration and shock damping air blower, generally designated in FIGS. 1 through 3 by the reference number 10. The focus of the invention is an improved mounting arrangement for supporting blower means within a flexible blower housing in a manner wherein the mounting arrangement and the flexible housing cooperatively absorb impact-created shock forces which previously tended to deform internal components of the air blower. The present invention advantageously prevents or minimizes such deformation and thus minimizes the chance that moving blower components will become misaligned and create undesirable vibration.
The air blower 10 of the present invention includes an outer housing 12 having a main body portion 14 suitably sized for housing blower means therein, and a nozzle portion 16 for directing air blown from the housing 12 by the blower means. The main body portion 14 is provided with one or more air intake grills 18 attached by screws 19 to cover respective housing openings 20 (FIG. 3), a handle 21, and an access aperture (not shown) for a power cord 22 that connects the blower means to a suitable power source. The nozzle portion 16 has an open end covered by an exhaust grill 24, that is in fluid communication with the blower means.
The blower means includes a blower wheel 26 (FIGS. 2 and 3) having of a plurality of parallel fan blades 28 arranged in a cylindrical configuration. The blower wheel 26 also has a central support web 30 adapted for attachment to a motor shaft 32 having one end which is rotatably driven by an electric motor 34 (illustrated with a capacitor 36 secured thereto by a strap 38). Rapid rotation of the blower wheel 26 by the motor 34 draws in air through the air intake openings 20, and expels air out of the housing through the nozzle 16 and past the exhaust grill 24.
The foregoing discussion of the housing and blower means is directed to aspects of the present invention which are deemed to be conventional. It is to be understood that although the present invention is illustrated and described in the environment of a squirrel cage fan air blower, it also has utility in air blowers having different blower wheels or other arrangements of motors and blower wheels.
In accordance with the present invention, the motor 34 includes a plurality of motor mounting studs 40 which are secured within first apertures 42 in a motor mounting bracket 44 by lock nuts 46. The motor mounting bracket 44 includes second apertures 48 that are aligned with apertures 50 in the outer housing 12 (FIG. 2). The motor mounting bracket 44 is attached to the outer housing 12 by a plurality of first shock mounts 52, each of which includes a hex bolt 54 having a resilient, elastomeric grommet 56 disposed about its shank between two washers 58, and a corresponding self-clinching nut 60 (FIG. 5). The grommet 56 of each shock mount 52 fits snugly within the second aperture 48 in the motor mounting bracket 44 such that the hex bolt 54 passing through the grommet 56 does not directly contact the motor mounting bracket 44. In this manner, the grommets 56 provide a resilient cushion around the shank of the hex bolts 54. To ensure that the grommet 56 will remain captured within its respective second aperture 48, each grommet is provided with a circumferential slot 61 about its midsection which receives a portion of the motor mounting bracket 44 surrounding the respective second aperture 48.
The grommets 56 serve as means for allowing flexion of the motor mounting bracket 44 with respect to the bolts 54. Construction of the housing 12 also preferably permits flexion of the bolts 54 with respect to the housing 12. More specifically, the bolts 54 function as a torsion arm system by pivoting relative to the housing 12 in any direction in a controlled full floating manner within their respective grommets 56 in response to impact-created shock forces. Thus, flexion of the motor mounting bracket 44 with respect to the bolts 54 through the grommets 56, and flexion of the bolts 54 with respect to the housing 12, cooperatively serve to absorb impact-created shock forces which could jar the motor and possibly deform the mounting arrangement.
The motor shaft 32 passes through a central aperture in the central web 30 of the blower wheel 26, and is clamped thereto by a lock nut 62. The lock nut 62 is threaded through a blower wheel support block 64 provided by the central web 30. The shaft 32 includes a slot 66 that provides a flat surface which the lock nut 62 engages when fully tightened.
The end of the shaft 32 opposite the motor 34 protrudes beyond the central web 30 of the blower wheel 26 and is supported by a flexibly resilient motor shaft support bracket 68. As best viewed in FIGS. 2 and 3, the motor shaft support bracket 68 includes a head portion 70 having an aperture therethrough for receiving the motor shaft 32, and a self-aligning bronze bearing 72 affixed to the head portion 70 adjacent to the aperture for supporting the shaft 32 in a manner permitting rotation of the shaft 32 with respect to the support bracket 68. The self-aligning bearing 72 accommodates radial deflection of the motor shaft 32, thereby damping stress and vibrational forces upon the motor shaft.
Four flexible support legs 74 extend angularly away from the head portion 70. These support legs are configured in a pyramid-like arrangement and are integrally formed with the head portion 70. The support legs 74 include an upper portion 75 and a lower portion 76 which lies in a plane parallel to the plane of the head portion 70. Each leg 74 also includes a foot 78 that lies in a plane generally perpendicular to the plane of the head portion 70. The flexibly resilient nature of the motor shaft support bracket 68 provides a plurality of flexion points whereby impact-created shock forces upon the housing 12 can be absorbed or damped by a flexing action of the support bracket 68.
Additional flexion points for damping vibration and shock forces are provided by the use of second shock mounts 80 to attach the motor shaft support bracket 68 to the housing 12. As best viewed in FIG. 4, the second shock mounts 80 are identical to the first shock mounts 52 previously described, and each includes a resilient elastomeric grommet 56 disposed between two washers 58 on the shank of a hex bolt 54 which is secured to the housing 12 by a self-clinching nut 60. Each foot 78 of the motor shaft support bracket 68 contains an aperture which accommodates the grommet 56 of the second shock mount 80 in a snug fit. As can be seen in FIGS. 4 and 5, both the motor mounting bracket 44 and the motor shaft support bracket 68 grip the grommets 56 about their circumferential slots 61 to capture the grommets 56 in place. This prevents the grommets from working themselves free from the grommet-accommodating apertures in both brackets 44 and 68.
The use of the second shock mounts 80 to attach the motor shaft support bracket 68 to the housing 12 enables the grommets 56 to function as means for allowing flexion of the support bracket 68 with respect to the hex bolts 54. FIGS. 6 through 9 illustrate various ways in which the resiliency of the grommets 56 permits flexion of the support bracket 68 with respect to the hex bolts 54. The first shock mounts 52 permit flexion of the motor mounting bracket 44 with respect to the hex bolts 54 in a manner similar to the action of the second shock mounts 80 depicted in FIGS. 6 through 9. The flexion points provided by the grommets 56 enable the motor shaft mounting arrangement to withstand impact forces and absorb vibration and impact-created shock forces by flexion so that permanent deformation of the mounting components is prevented. The resiliency of the elastomeric grommets 56 ensures that the mounting components return to their original orientation following flexion.
A feature of the present invention which further enhances the vibration and shock damping capability of the air blower 10 is the use of a flexibly resilient outer housing 12 which can temporarily flex to absorb impact forces and then resiliently return to its original shape. Preferably, the outer housing 12 is comprised of a polyethylene material. The flexing action provided by the flexible outer housing 12 serves to dissipate and absorb impact forces before such forces are transferred to components within the housing. Moreover, the bolts 54 of the second shock mounts 80 flex relative to the housing 12 to further help dissipate and absorb impact forces.
The shock damping air blower 10 provides a multi-directional energy absorbing flexation system which has six progressive levels of shock resistance that are available to supply the damping effect required. One level of damping is provided by multi-directional flexion of the first and second shock mounts 52 and 80, which absorb the initial shock upon the blower. Another level of shock damping is provided by flexion of the motor shaft support bracket 68. The self-aligning bearing 72 between the motor shaft and the motor shaft support bracket provides a third level of damping which compensates for multi-directional, non-parallel flexing of the support legs 74. Radial deflection of the motor shaft 32 provides a fourth level of shock damping. A fifth level of energy absorption is provided by the flexible plastic housing 12, and finally, the action of the hex bolts 54 as a torsion arm system provides the sixth level of shock damping, wherein the hex bolts 54 can pivot relative to the housing 12 in a controlled full-floating manner within the grommets 56.
The energy absorption system of the present invention also functions in reverse in the sense that when vibrations are created internally by, for example, out of balance blower components, the system will dampen vibration transfer between the internal blower components and the outer housing. This feature advantageously prevents the air blower from "walking" or bouncing when placed on hard surfaces, a long-standing problem in the industry.
From the foregoing, it will be appreciated that the vibration and shock damping air blower of the present invention advantageously provides flexion points at first and second shock mounts, at a flexible motor shaft support bracket, and at attachment locations between mounts for the blower means and the flexibly resilient blower housing. This permits the air blower to absorb vibration and shock forces by flexing at these flexion points. The result is an improved air blower which is substantially impact-damage resistant.
While a particular form of the invention has been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims. | A portable air blower includes a flexibly resilient housing, a motor mounted within the housing, and a blower wheel fixed to a motor shaft. The motor is bolted at one end to a motor mounting bracket which, in turn, is attached to the housing by a plurality of first shock mounts. Each such first shock mount includes a bolt for connecting the motor mounting bracket with the housing, and a resilient elastomeric grommet interposed between the bolt and the bracket. A self-clinching nut fixes the bolt to the housing. The motor shaft rotates through a self-aligning bearing held by a pyramid-like support bracket which is attached to the housing by a plurality of second shock mounts. The second shock mounts are identical to the first shock mounts, and include a resilient elastomeric grommet interposed between the support bracket and the bolt. | 5 |
This application is a Continuation of International application No. PCT/AT2008/000056, filed Feb. 22, 2008.
BACKGROUND OF THE INVENTION
The present invention concerns a drive for a movable furniture part, in particular a furniture drawer, comprising an ejection device having an ejection lever and an electric motor for driving the ejection lever.
By virtue of such a drive, it is possible to eject the movable furniture part from its closed end position in or on a furniture body or carcass, into an at least partially open position. It is however not possible to move the movable furniture part in an opposite relationship to the opening direction in order, for example, to transfer it into the closed end position.
The object of the invention is to develop a drive of the general kind set forth, in such a way that its functionality is enhanced but the drive is not more complicated and expensive to fit.
SUMMARY OF THE INVENTION
The provision of a retraction device allows the application of forces to the movable furniture part in the retraction direction. A cable line, for example, presents itself as a pulling means. It is however also possible to provide pulling means having a certain stiffness (such as for example metal bands).
The mechanical connection of the ejection device and the retraction device to afford a structural unit ensures that the drive with the combined functionalities is equally simple to fit as a drive in accordance with the state of the art, which has only an ejection device.
For example, the ejection device and the retraction device are arranged on a common mounting plate. A particularly preferred embodiment of the invention, however, is one in which the ejection device and the retraction device are arranged in a common housing.
It is particularly advantageous if the housing has a stirrup arrestable by a lever for fastening the drive to a profile bar without a tool. That permits particularly simple mounting of the drive.
In principle, a drive according to the invention can have an electric motor assembly with respective dedicated electric motors for the ejection device and the retraction device.
In that case, it is desirable if the ejection device and the retraction device have respective dedicated transmissions for the transmission of force from the respective electric motor to the ejection lever and the roller respectively so that the drive train of the ejection device and that of the retraction device remain mechanically separated from each other.
In such a case, coupling of the ejection device and the retraction device can be effected electronically by a common control or regulating unit.
Alternatively, it can be provided that the ejection lever of the ejection device and the roller of the retraction device are drivable by an electric motor assembly with one common electric motor for driving both the ejection device and the retraction device. This embodiment has the advantage that only a single electric motor is required per drive.
The operation of switching over the transmission of force from the electric motor to the ejection lever of the ejection device or to the roller of the retraction device respectively can be effected by a wide range of different couplings. A particularly preferred embodiment, however, is one in which the transmission of force from the electric motor is effected selectively to the ejection lever or the roller by way of a planetary transmission. A planetary transmission of that kind is distinguished by a particularly compact structure, which is of significance in particular when the ejection device and the retraction device are arranged in a common housing.
In this embodiment, the planetary transmission is of a two-stage nature, wherein the one stage serves for the transmission of force from the electric motor to the ejection lever, and the second stage serves for the transmission of force from the electric motor to the roller. Selection of the respective stage can be effected by way of a brake which is switchable by a control or regulating device and which, for example, can be in the form of a solenoid brake.
Each of the two stages of the planetary transmission can have its own hollow ring gear in which the respective planetary gears are accommodated. The brake of each stage co-operates with the respective ring gear. Fixing the respective ring gear by the respective brake causes a rotational movement of the planetary gears.
In an embodiment of the invention, in the stage associated with the ejection unit, the transmission of force is effected with the planetary gears rotating. In the stage associated with the roller, the transmission of force occurs with the planetary gears stationary. That arrangement provides that the mutually opposite directions of rotation of the ejection lever and the roller can be implemented with the same direction of rotation of the electric motor.
By way of example, three planetary gears can be provided for each stage.
The sun gear of the planetary transmission is formed in each stage by a common shaft drivable by the common electric motor.
As already stated a common control or regulating device for controlling or regulating the ejection device and the retraction device can be provided in each of the above-mentioned embodiments.
In each embodiment of the drive, the ejection device can have a touch-latch functionality. That means that the ejection device is triggerable in the closed and/or partially or completely opened end position of the movable furniture part, by an application of force to the furniture part. The configuration of the ejection device, that is necessary for that purpose, was already disclosed in Austrian patent AT 413 472 (see in particular page 4, paragraphs 3 through 7; page 7, paragraphs 4 and 5; page 8, paragraph 6 and the Figures referred to therein) so that there is no need for a more detailed description at this juncture.
The retraction device can also be provided with such a touch-latch functionality so that overall this provides a drive having a touch-latch functionality. For that purpose, it is necessary for the roller to be biased in the winding-on direction by a force storage means so that the pulling means is constantly held under a mechanical tension in the retraction direction. By virtue of that arrangement, an application of force to the movable furniture part by a user can be transmitted to the roller by way of the pulling means and can be detected by way of suitable means (for example rotary potentiometers).
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages and details of the invention will be apparent with reference to the drawings and the related specific description. In the drawings:
FIG. 1 shows a perspective view of an embodiment of a drive according to the invention with a common housing,
FIGS. 2 a and 2 b show the drive train of a first embodiment of a drive according to the invention as a perspective view and a block-wise exploded view,
FIGS. 3 a and 3 b show a detail view of FIGS. 2 a and 2 b as a perspective view and an exploded view,
FIGS. 4 a through 4 e show the drive train of a second embodiment of a drive according to the invention in various perspective views and sectional views, and
FIGS. 5 a through 5 c show the drive train illustrated in FIGS. 4 a through 4 c in further views and as a detail view.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a perspective view of a drive 1 according to the invention in which all components are arranged in a common housing 2 or mounted therein. It is possible to see in particular the ejection lever 3 of an ejection device and the pulling member 4 of a retraction device. The drive 1 can be fastened without a tool to a profile bar (not shown) in a furniture body or carcass by way of the lever mechanism denoted by reference 5 .
FIG. 2 a shows a perspective view of the first drive train 6 , 9 , 3 of the ejection device and the second drive train 7 , 10 , 8 of the retraction device for a first embodiment of a drive 1 according to the invention, in which the ejection lever 3 of the ejection device and the roller 8 of the retraction device are drivable by an electric motor assembly with separate electric motors 6 and 7 respectively, and there are respective dedicated transmissions 9 and 10 for the transmission of force.
The first drive train 6 , 9 , 3 of the ejection device has a first transmission 9 by which the rotary speed of the electric motor 6 (for example about 6000 rpm) can be reduced by way of a series of gears. It can further be seen that the ejection lever 3 is provided in a known manner (see for example FIG. 17 of AT 413 472 B) with a tooth configuration 12 with which a rotary potentiometer (not shown) meshes to ensure a touch-latch functionality.
The second drive train 7 , 10 , 8 of the retraction device has a second transmission 10 for reducing (about 40:1) the rotary speed of the second electric motor 7 (for example, about 12,000 rpm) and is shown in detail in FIGS. 3 a and 3 b.
FIG. 2 b shows that the first and second drive trains 6 , 9 , 3 and 7 , 10 , 8 in the mounted position shown in FIG. 2 a are mechanically separated from each other and are pushed as close together as possible only for reasons of space.
FIG. 3 a shows the second transmission 10 together with the roller 8 which is driven by the second transmission 10 and on which the pulling member 4 is wound. The pulling member 4 is passed out of the housing 2 (not shown here) by rollers 13 and is provided at its free end with a coupling portion 48 to be connected to a corresponding coupling portion (not shown) on the movable furniture part.
The second electric motor 7 drives the gear 14 by way of its worm. The gear 14 is non-rotatably connected by the shaft 15 to the gear 16 . The gear 16 meshes with the gear 17 which in turn meshes with the gear 18 . The gear 18 is non-rotatably connected to a square region 19 serving for the transmission of force to the roller 8 . In this arrangement, connected between the square region 19 and the roller 8 is a slipping clutch 20 through 23 which is described in detail in Austrian patent application A 1769/2006. This involves a wrap spring clutch, the outer casing 22 of which is slightly braked by the spring 23 , leading to immediate shifting of the clutch.
The roller 8 is biased in the winding-on direction by a force storage means 24 .
Non-rotatably connected to the roller 8 is a worm attachment 25 meshing with the drive gear 26 of a rotary potentiometer. In that case, the rotary potentiometer serves to determine the position of the roller 8 to implement a touch-latch functionality and the position as a movable furniture part.
FIGS. 4 a through 4 e show the drive train of a second embodiment of a drive 1 according to the invention, including an electric motor assembly with a common (single) electric motor 6 for driving both the ejection lever 3 and the roller 8 (see FIG. 5 ).
In this case, a planetary transmission 11 is provided for the selective transmission of force to the ejection lever 3 of the ejection device and the roller 8 of the retraction device respectively (see the perspective view in FIG. 4 a ). The structure of the planetary transmission 11 will be described with reference to FIG. 4 b in conjunction with FIGS. 5 a through 5 c . The flow of force through the planetary transmission 11 is diagrammatically shown in FIGS. 4 c through 4 e.
The planetary transmission 11 has a first drive gear 27 drivable by way of the gears 28 and 29 by the worm 30 of an electric motor 6 (see FIG. 5 a ).
The drive gear 27 is arranged non-rotatably on the shaft 31 which functions as the sun gear of the planetary transmission 11 . Arranged on the same shaft 31 is a gear carrier 32 which by way of pins 35 carries three planetary gears 34 (only two planetary gears 34 can be seen in FIG. 4 b ). Arranged integrally with the gear carrier 32 between the gear carrier 32 and the first drive gear 27 is a square region 33 , on to which the ejection lever 3 of the ejection device can be fitted for drive purposes. Jointly with a ring gear 36 which is toothed at the inside (i.e., has internal teeth), the first stage of the planetary transmission 11 is formed by the components 32 , 33 , 34 , 35 and 36 and the shaft 31 as the sun gear.
Arranged beneath the first ring gear 36 is a second ring gear 38 carrying three planetary gears 39 (only two can be seen). The planetary gears 39 mesh with the internal teeth of a roller gear 40 which is formed integrally with the roller 8 and with the intermediate gear 37 non-rotatably connected to the shaft 31 . The roller gear 40 further has external teeth 41 which mesh by way of a gear 42 and a gear 43 with a rotary potentiometer (not shown) (see FIG. 5 a ).
The second stage of the planetary transmission 11 is formed by the components 37 , 38 , 39 and 40 and the shaft 31 as the sun gear.
The functionality of the planetary transmission 11 will also be described in particular with reference to FIGS. 4 c through 4 e . In this respect, for the sake of enhanced clarity, only the respective relevant components are denoted by reference numerals in FIGS. 4 d and 4 e.
FIG. 4 d shows the transmission of force from the electric motor 6 to the ejection lever 3 of the ejection device. The application of force is effected by way of the drive gear 27 to the shaft 31 . The brake 44 associated with the first stage of the planetary transmission 11 (this cannot be seen in FIG. 4 d as it is on the rear side which cannot be viewed) brakes the first ring gear 36 of the first stage by way of a first wrap spring 45 . That causes a rotational movement of the planetary gears 34 in the first ring gear 36 , in meshing engagement with the internal teeth of first ring gear 36 . That arrangement provides that, by way of the pins 35 , the gear carrier 32 and the square region 33 arranged thereon are rotated. That rotation drives the ejection lever 3 of the ejection device.
In the meantime, the brake 44 of the second stage remains inactive. The second ring gear 38 of the second stage can freely rotate jointly with the planetary gears 39 fixed thereto. By virtue of that situation, no force is transmitted to the roller gear 40 and the roller 8 .
The situation is different in FIG. 4 e . Here the brake 44 (see FIG. 5 a ) of the second stage is active and presses the second wrap spring 46 against the second ring gear 38 . Due to second the ring gear 38 being fixed, the planetary gears 39 remain stationary and mesh on the one hand with the intermediate gear 37 driven by the shaft 31 and on the other hand with the internal teeth of the roller gear 40 . As a result, the drive force is transmitted from the intermediate gear 37 (sun gear) by way of the planetary gears 39 to the roller gear 40 and thus to the roller 8 .
The first stage (transmission of force to the ejection lever 3 ) therefore has a first set of planetary gears 34 which rotate during the transmission of force whereby the gear carrier 32 carrying the planetary gears 34 by way of the pins 35 is set in motion.
In contrast thereto, the second stage (for the roller 8 ) has a second set of planetary gears 39 which are stationary during the transmission of force as in fact the second ring gear 38 on which the planetary gears 39 are mounted is fixed by the wrap spring 46 . That situation involves the transmission of force from the shaft 31 and the gear 37 by way of the planetary gears 39 to the gear 40 . The direction of rotation, however, is reversed in comparison with the first stage. That is also to be required as in fact the drive direction for ejection or retraction respectively of a movable furniture part must be in mutually opposite relationship, while the direction of rotation of the shaft 31 is unchanged.
The structure of the brake 44 is also of interest, as can be seen from FIGS. 5 b and 5 c . It can be seen that the brake 44 has a pushrod 47 which, when the brake 44 is activated, presses against the associated wrap spring 45 or 46 , respectively. In this embodiment, the brakes 44 are in the form of solenoid brakes. | A movable furniture part, such as a furniture drawer, includes an ejector device having an ejector lever and an electric motor for driving the ejector lever. A retracting device has a pulling member that can be wound onto a roll. The roll can be driven by an electric motor, and the ejector device and retracting device are mechanically connected to one another such that they can be mounted as a unit in or on a furniture body. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a national stage filing in accordance with 35 U.S.C. §371 of PCT/US2012/036115, filed May 2, 2012, which claims the benefit of the priority of U.S. Provisional Patent Application No. 61/481,537, filed May 2, 2011, entitled, “Strength Training Aid”, the contents of which are incorporated herein in their entirety.
FIELD OF THE INVENTION
The present invention relates to the field of strength training devices, and in particular to a device that develops strength in the forearms, upper arms and shoulders. The present invention enables an individual to increase his/her strength and ability to participate in various sports.
BACKGROUND OF THE INVENTION
There are various devices for strengthening the hands, wrists, forearms, upper arms, back and shoulders. These devices operate on the principles of variable threading, tension, torque, and compression mechanisms. These devices range from simple spring like devices which are operated in one hand such as free weights to complicated machines which can develop multiple muscles and muscle groups simultaneously. Strength training devices are currently available for everyone from the casual athlete to the professional athlete. The strength training devices which the professional athletes use are usually complex, relatively expensive, and generally not available for the average person/athlete. Another problem with the strength training equipment that professional athletes use is that it is designed for a specific sport. An individual who wants to play multiple sports would need to purchase many different pieces of strength training equipment.
DESCRIPTION OF THE PRIOR ART
U.S. Pat. No. 5,709,637 discloses a portable exercise device for specific strength training of the rotator cuff. The device includes a cylindrical spool which has a handle across its diameter. A length of elastic tubing is secured tangentially to one point of the spool. The opposite end of the elastic tubing is securable to a fixed point or object. This permits an individual to grip the handle and rotate or move the spool against a continuous resistance for muscle development.
U.S. Published Patent Application No. 2002/013599 discloses a strength training device for developing the forearms, upper arms, and shoulder muscle groups. The device includes two cylindrical handles with fixed concave surface end caps that are connected by a cylindrical center joint piece. The center piece has a concave surface on top and an under body cavity on the bottom. One end of an exercise cord is secured to the center joint piece. The opposite end of the exercise cord is secured to free weights. The free weights are raised and lowered by an individual rotating the cylindrical handles toward their body and away from their body. Weight machine cables can also be secured to the center joint piece. This enables an individual to perform bicep curls and triceps extension exercises.
Therefore, there is a need in the strength training art to provide a device which is portable, adjustable, and easy to use. The training device should be relatively simple in construction and portable for easy transport and use at remote locations. The device should also be capable of adjustment for athletes having a range of strength ranging from beginning amateurs to professional athletes. The device should also be adaptable for use by athletes training for various sports without the need for complex tools or scores of auxiliary parts.
SUMMARY OF THE INVENTION
The present invention relates to a portable strength training device which can be adapted to various sports and can be utilized in almost any location. More, specifically present invention is a weighted elongated tubular member which includes connectors for attachment of various balls and/or sporting equipment. The training device is adjustable through the use of various sized hollow tubes of different lengths and/or diameters which allow for the addition of one or more types of weight material within the hollow lumen. Materials such as sand, lead shot, steel shot or the like can be utilized within the hollow tubes to increase or decrease the weight of the tubes. While materials such as rubber chunks, springs or the like that affect the action of the tube may be mixed with the weight material to vary the training provided by the device. Various different sports objects, such as balls, golf club handles, tennis racket handles, baseball bats and the like can be secured to one of the distal ends of the hollow tubes. Clips hooks or the like may be secured to the opposite distal end of the tube for anchoring the device. Handles or the like may be utilized in place of the clips or hooks to allow a second person to provide anchoring or action to the tube and thus the person training. In addition, the tube may be provided in a resilient elastic or non-elastic construction to add additional training options to the user. These various features enable the device to be tailored by an individual for various types of training and for different sports.
Accordingly, it is an objective of the present invention to provide a training device which can be utilized for training athletes involved in various sports.
It is a further objective of the present invention to provide a portable training device for various sports which can be readily used in many different locations.
It is yet another objective of the present invention to provide a portable training device for various sports which can be readily adjusted.
It is a still further objective of the present invention to provide a portable training device which can readily be adapted to different sports.
It is still a further objective of the present invention to provide a portable training device which can be readily adjusted to provide different resistance and/or weights.
Other objects and advantages of this invention will become apparent from the following description taken in conjunction with any accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. Any drawings contained herein constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of one embodiment of the present invention;
FIG. 2 is a perspective view of an alternative embodiment of the present invention;
FIG. 3A is a cross sectional view taken along lines 3 A- 3 A of FIG. 1 , illustrating the hollow tubular member of the present invention;
FIG. 3B is a cross sectional view taken along lines 3 B- 3 B of FIG. 1 , illustrating the quick release connection between a ball and the hollow tubular member;
FIG. 4 is a partial perspective view of the embodiment illustrated in FIG. 1 ;
FIG. 5 is a perspective view of an alternative embodiment of the present invention; and
FIG. 6 is a perspective view of an alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred, albeit not limiting, embodiment with the understanding that the present disclosure is to be considered an exemplification of the present invention and is not intended to limit the invention to the specific embodiments illustrated.
FIGS. 1-4 , which are now referenced, illustrate one embodiment of the present invention and the manner in which it is assembled. In general, the strength training device 10 comprises a hollow tubular member 12 , a training object 14 removably secured to one end of the hollow tubular member 12 , and a fastening device 16 secured to an opposite end of the hollow tubular member. More specifically, the hollow tubular member 12 is preferably made from a flexible, non-elastic material such as a reinforced rubber and may include various filler materials 13 which vary the weight and action provided by the tubular member. For example, sand alone may be added to give one weight and a relatively dead action to the tubular member. Alternatively, a filler such as steel shot may be combined with rubber particles or beads to result in a different weight and substantially more action provided by the tubular member. Various other combinations of materials may be added singularly or combination to allow the athlete to tailor his training to his particular needs. In this manner, the athlete may train for strength, speed agility, dexterity and the like with a single training tool by altering its properties. In the embodiment illustrated in FIGS. 1-4 the training object 14 is illustrated as a baseball 30 is secured to one end of the hollow tubular member. The ball may be directly adhered to the tubular member as illustrated in FIG. 2 or alternatively and preferably, a swiveling quick release coupling 20 may be provided to allow the user to change training objects 14 . The quick release coupling 20 preferably includes a ring 22 , button or the like which may be slid or moved to release the training object from the distal end of the tubular member 14 . The training object 14 preferably includes a stem 24 secured to the training object via threaded stud 26 , adhesive 28 or the like. The stem 24 is generally constructed and arranged to cooperate with the quick release coupling 20 to create an operator securable connection and release. A filler cap 28 may be secured to or formed as portion of the quick release to facilitate access to the lumen 18 . In a preferred embodiment, the filler cap cooperates with a threaded terminal 32 . The threaded terminal includes a sleeve 34 which cooperates with the outer or inner surface of the tubular member for attachment thereof. A fastening device 16 , such as a carabiner 17 , hook or the like is secured to an opposite end or second end 38 of the tubular member 14 to allow the person training to secure the second end of the tubular member to a fixed object. In operation, an individual would secure the carabiner 17 to a fixed object. Afterwards the trainee can simulate throwing, pitching or catching the ball. The additional weight of the hollow tubular member helps to strengthen the muscles associated with throwing, pitching or catching the ball. The carabiner secures the hollow tubular member to a stationary object so that it will not fly around when in use. Also, securing the training device to a stationary object prevents the training object from being thrown away or hitting another individual. The trainee can alter the properties of the tubular member by adding or deleting fillers within the tube.
Referring to FIG. 3A , a cross sectional view illustrating the hollow tubular member 12 partially filled with a filler material 13 for modifying the properties of the tubular member. The preferred substance is a granular material characterized by a loss of energy whenever the particles collide such as sand. However, other substances can be employed, such as lead shot, BB's, crushed shells, crushed gravel and the like. Other suitable materials include materials suitable for absorbing energy, some of which may be released by causing a secondary motion in the tubular member, examples include, but should not be limited to, rubber chunks, springs, water, and other fluids. The only criteria for the filler materials 13 are that they can generally flex and/or conform to the shape of the lumen within the hollow tubular member 12 . FIG. 3 illustrates the hollow tubular member 12 being filled with sand 40 and rubber 42 . The amount of the substance utilized in the present invention depends on the additional weight and type of action resulting from movement an individual wants to add to the training object. The hollow tubular member 12 can be completely empty, partially full, or completely full of filler 13 . While the preferred embodiment of the hollow tubular member is flexible and non-elastic, it can also be made from an elastic material whereby all or portions of the tubular member are allowed to elastically expand or stretch.
While subject to the trainee's preferences, when the training object is relatively small, such as a baseball or a softball, the amount of filler 13 added to the hollow tubular member is relatively small. When the training object is relatively large, such as a basketball or soccer ball, the amount of filler 13 added is relatively large. For example, when a basketball is utilized the individual will simulate shooting the basketball or passing the basketball. The repetitive throwing or handling motion of the training object results in an increase in the strength of an individual performing these motions. Additionally, the amount of filler 13 in the hollow tubular member 12 can be increased as the individual progresses in their training. This will present additional resistance during the training sessions and lead to an increase in strength. This is similar to adding weights to certain exercises in weight training.
While the preferred embodiment illustrates a baseball as the training object 14 utilized with the training device 10 , other objects can also be employed. For example, a softball, a basketball, a soccer ball, or a football. Additionally, objects such as a straight bar, a curved bar, or a handle can also be secured to the hollow tubular member. These additional training objects can be utilized to develop specific muscle or muscle groups related to tennis, golf, racquetball, baseball or any other sport which requires the player to swing an elongated instrument.
Referring to FIG. 5 , a perspective view of an alternative embodiment of the present device is illustrated. In this embodiment, the first end 36 of the tubular member 12 is secured directly to the training object 14 , illustrated herein as a football 44 . Attached to the second end 38 of the tubular member is a hand grip 46 and swivel 48 . Also in this embodiment, the swivel is removably secured to the second end of the tubular member to allow the lumen of the tubular member to be filled to alter its workout properties as described above. The hand grip 46 provides the ability for a second person to provide motion or tension to the tubular member for additional training.
Referring to FIG. 6 , a perspective view of an alternative embodiment of the present device is illustrated. In this embodiment, the first end 36 of the tubular member 12 is secured directly to the training object 14 , illustrated herein as a golf club shaft 50 . Attached between the first end 36 of the tubular member and the golf club shaft 50 is a universal swivel 52 . The universal swivel is constructed and arranged to flex in a polyaxial manner as well as swivel in a planer manner. The universal swivel is removably secured to the filler cap 28 of the tubular member to allow the lumen of the tubular member to be filled to alter its workout properties as described above. A carabiner 17 is secured to the second end 38 of the tubular member for securing the tubular member to a fixed object. It should be noted that while a golf club shaft is illustrated, a baseball/softball bat, tennis racket handle, racquet ball racket or the like having a substantially rigid elongated shaft with a hand grip 56 mounted at a distal end thereof may be utilized without departing from the scope of the invention.
All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and any drawings/figures included herein.
One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims. | The present invention relates to a portable strength training device which can be adapted to various sports and can be utilized in almost any location. More, specifically present invention is a weighted elongated tubular member which includes connectors for attachment of various balls and/or sporting equipment. The training device is adjustable through the use of various sized hollow tubes of different lengths and/or diameters which allow for the addition of one or more types of weight material within the hollow lumen. Various different sports objects, such as balls, golf club handles, tennis racket handles, baseball bats and the like can be secured to one of the distal ends of the hollow tubes. Clips hooks or the like may be secured to the opposite distal end of the tube for anchoring the device. | 0 |
FIELD OF THE INVENTION
The present invention relates to a system for storing and delivering cassettes to a device, and in an important embodient to the storage and delivery of cassettes containing liquid sterility to a sterilizing device.
BACKGROUND OF THE INVENTION
U.S. Pat. No. 4,643,876, incorporated herein by reference, discloses a sterilization system in which an agent such a hydrogen peroxide is introduced into a evacuated sterilizing chamber where it is vaporized and allowed to disperse onto the items to be sterilized. After a desired period of time, electrical energy is applied to the chamber to ionize the gas and form a plasma field at a power level sufficient to achieve sterilization.
This system has been successfully commercialized as the STERRAD® Sterilization system and is available from Advance Sterilization Products, Division of Ethicon, Inc., Irvine, Calif. The system is used in hospitals and other environments where it is operated repeatedly throughout the day by personnel having a widely varying range of understanding of the apparatus. To ensure simple and automatic operation with adequate safeguards with respect to human error, the system employs an automated delivery system for delivering the liquid sterility to the sterilization chamber. Measured portions of the sterility, in this case hydrogen peroxide but many other sterilizing agents could be substituted therefor, are provided in rupturable cells within a rigid cassette housing. A transport system maneuvers the cassette within the Sterrad® sterilizer and releases the given quantity of hydrogen peroxide into the sterilin chamber automatically. The cassette and operation of the deliver system are more fully described in the Williams et al, U.S. Pat. Nos. 4,817,800 issued Apr. 4, 1989; 4,913,196 issued Apr. 3, 1990; 4,938,262 issued Jul. 3, 1990; and 4,941,518 issued Jul. 17, 1990, all of which are incorporated herein by reference In this system, the operator manually grasps the cassette housing and inserts it into the sterilizer. When spent, the cassette is ejected and manually handled by the operator.
This sterilization device with the cassette system offers many advantages. The hydrogen peroxide and plasma kill a wide spectrum of bacteria, viruses, and spores at low temperatures which leave delicate temperature sensitive instruments undamaged. Hydrogen peroxide plasma sterilization meets several environmental and operator safety challenges. After the electromagnetic field producing the plasma is removed, the ionized plasma components recombine to form harmless water and oxygen, avoiding toxic disposal of the sterility used in the sterilization process. Also, the cassette effectively isolates the operator from the hydrogen peroxide contained therein.
One potential hazard arises from small drops of residual hydrogen peroxide which may be left on the exterior of a spent cassette. A sharp hollow needle pierces the cell which is then pressurized to extract the hydrogen peroxide solution through the needle. In some instances, it is possible for a drop of the solution to escape around the needle and thus remain on the cassette exterior after the extraction process. If an operator's skin or clothing were to contact this droplet, damage could result thereto. Also, operators have been known to accidentally insert a spent cassette into the sterilizer in the mistaken belief that it was actually a new cassette filled with sterility. Safety mechanisms in the process such as methods for detecting the presence of sterility during the sterilization cycle and biological indicators assessing the sterilization cycle efficiency. warn operators of potential cycle failures to prevent inadvertent use of non-sterile instruments thereafter. However, failure of a cycle due to use of a spent cassette entails delays and concomitant expenses.
The present cassette and delivery system encase the cassette within a protective sleeve which isolates the cassette from the operator's hands during all aspects of the cassette handling, thus protecting the operator from contact with any of the sterility contained therein. Further, an indicator on the sleeve, preferably a moveable label, indicates when the cassette has been used to prevent inadvertent re-use of a spent cassette.
SUMMARY OF THE INVENTION
A cassette assembly according to the present invention comprises a cassette having a first side and a first end and a protective sleeve containing the cassette. The sleeve comprises a first side and a first end, the first side having a window aperture therethrough. A label member within the sleeve has indicia thereon and is rotatably mounted about a first hinge adjacent the window aperture. The label moves between at least two position. In a first position of rotation about the first hinge, with the cassette within the sleeve, the label indicia is in registry with the window aperture and is visible therethrough. In a second position of rotation about the first hinge, with the cassette within the sleeve, the label indicia is out of registry with the window and indicia is not visible through the window aperture. The first hinge is oriented with respect to the sleeve first end so that when the cassette is inserted through the first end, the cassette abuts the label member and urges it about the hinge into the second position. Thus, extraction of the cassette from the sleeve and reinsertion of the cassette into the sleeve moves the label member from the first position to the second position to indicate that the cassette has been at least once extracted from the sleeve.
Preferably, the label member further comprises a biasing means to bias the label away from the first position when the cassette is not received within the sleeve. The biasing means can comprises an elastic member which urges the label member away from the first position, the label member having a mass and the sleeve being oriented so that gravity urges the mass of the label member away from the first position, a combination of the two, or other appropriate biasing.
Preferably, the label comprises an adhesive label adhered to the sleeve adjacent the window aperture and the first hinge comprises a fold line on the adhesive label. The sleeve can be formed of stock and further comprise a cut-out adjacent the viewing window which forms a removable panel of the stock, the adhesive label being attached thereto whereby the panel stiffens the label and defines the fold line thereon.
A retaining member, connected to the sleeve by a second hinge at the sleeve first end, can be provided to hold the cassette within the sleeve for easy removal. The retaining member rotates about the second hinge from a first position in which the retaining member blocks the travel of the cassette out of the sleeve through the sleeve first end and a second position in which the retaining member does not block travel of the cassette out of the sleeve through the sleeve first end. Preferably, the sleeve is formed of foldable stock, the retaining member comprises a flap, the second hinge comprises a first fold line in the stock and the biasing means comprises the tendency for the stock to unfold along the first fold line in the stock. The retaining member preferably extends from the second hinge, between the sleeve and the cassette, to a terminal edge which abuts a surface on the cassette when the retaining member is in its first position to block travel of the cassette out of the sleeve through the sleeve first end.
A method for delivering a cassette to a device according to the present invention comprises the steps of placing the cassette within a protective sleeve having an open end, hingably mounting a label member with an indicia thereon within the sleeve, rotating the label member into a first position with the indicia visible through a window aperture through the sleeve, abutting the label member with the cassette when the cassette is within the sleeve to hold the label member in the first position, sliding the cassette out of the sleeve through its open end; processing the cassette in the device; and sliding the cassette back into the sleeve through its open end and abutting the label member thereby to swing the label member to a second position with the indicia out of register with the window aperture and not visible therethrough.
The step of processing the cassette can comprise removing a substance from the cassette. The steps of sliding the cassette out of and back into the sleeve through its open end are preferably performed by a machine. The label indicia is preferably read with a sensor prior to the step of processing the cassette in the device. An automatic control unit can control these steps and is preferably programmed to not perform the steps of processing the cassette if the sensor fails to first read the presence of the label indicia, or if the indicia indicates something improper about the cassette. For instance, if the cassette is out of date, or contains the wrong type of material, or the wrong quantity, it can be rejected.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a cassette within a sleeve in accordance with the present invention;
FIG. 2 is an exploded view of the cassette and sleeve of FIG. 1;
FIG. 2A is a view taken along line 2A--2A of FIG. 2;
FIG. 2B is a sectional view taken along line 2B--2B of FIG. 1;
FIG. 3 is a plan view of an unfolded blank forming an inner layer of the sleeve of FIG. 1;
FIG. 4 is a plan view of an unfolded blank of an outer layer of the sleeve of FIG. 1;
FIG. 5 is a perspective view of an identifying label according to the present invention on the sleeve inner layer of FIG. 3;
FIG. 6 is a sectional view of the label of FIG. 5 shown in the retracted position;
FIG. 7 is a sectional view as in FIG. 6, showing the label in a transitional orientation;
FIG. 8 is a sectional view as in FIG. 6, showing the label in the exposed orientation wherein the label is viewable through an aperture;
FIG. 9 is a cut-away view of the cassette and sleeve of FIG. 1 positioned within a cassette handling mechanism and showing the cassette upon entry into the handling system;
FIG. 10 is a view of the cassette, sleeve and handling system in accordance with FIG. 9 and showing the cassette traveling out of the sleeve;
FIG. 11 is a view of the cassette, sleeve and handling system in accordance with FIG. 9 and showing the traveling back into the sleeve;
FIG. 12 is a view of the cassette, sleeve and handling system in accordance with FIG. 9 and showing the cassette repositioned within the sleeve in preparation for leaving the handling system;
FIG. 13 is a cut-away perspective view of the cassette and sleeve assembly entering the cassette handling assembly;
FIG. 14 is a front and-top cut-away perspective view of the cassette handling system;
FIG. 15 is a front and bottom cut-away perspective view of the cassette handling system; and
FIG. 16 perspective view of a sterilizing chamber and fluid extraction mechanism.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates an assembled cassette assembly 20 comprising a sleeve 22 containing a cassette 24 and the exploded view of FIG. 2 illustrates the components of the cassette assembly 20 in more detail. The sleeve 22 has an open end 23 and a closed end 25 and comprises an inner layer 26 of corrugated cardboard and an outer layer 28 of an attractive pressboard material. The cassette 24 comprises an elongated, rectangular plastic shell 30 containing a plurality of cells 32 containing a 58% solution of hydrogen peroxide. As seen in FIG. 2a, the cassette shell 30 is formed of an upper housing section 34 which mates with a lower housing section 36 to capture and to enclose a cell strip 38. The cell strip 38 is formed of a flexible material and contains the cells 32. Each cell 32 contains a precisely measured amount of hydrogen peroxide 40. Of course, other liquid sterilants may be substituted therefor. Preferably, the cassette shell 30 and cell strip 38 are formed of suitable polymers such as polystyrene and polyethylene, respectively. However, one of skill in the art will recognize that other materials may be substituted therefor. Each of the cells 32 is accessible by a hollow needle 42 through an aperture 44 in the cassette shell 30.
Returning to FIG. 2, the sleeve inner layer 26 wraps about the cassette 24. Thus, if any small droplets of the hydrogen peroxide solution are left on the outside of the cassette 24 after use, they will be absorbed by the cardboard of the sleeve inner layer 26 thereby preventing contact with an operator's hands or clothing. The sleeve inner layer 26 provides several other important functions as will become apparent. As is also seen in FIG. 3, the sleeve inner layer 26 folds about a pair of parallel fold lines 46 to form an upper panel 48, an end panel 50, and a lower panel 52. A pair of longitudinal fold lines 54 forms a first side panel 56 and second side panel 58. A large arrow shaped aperture 60 in the upper panel 48 points toward the sleeve open end 23. Also, a tab 62 comprises a small longitudinally elongate cutout that remains attached at its rearward end 66 (toward the sleeve closed end) thereby forming a fold line 68 about which the tab 62 rotates through 180°.
A label 70, preferably with computer readable indicia 72 such as a bar code, identifies the cassette assembly 20. A large lateral rectangular aperture 74 form a window through which the label 70 becomes visible A tangular cutout 76 sits immediately rearward of the window are 74 and forms a removable panel 78 of cardboard, which fits within the cutout 76. The label 70 has adhesive on its surface opposite the indicia 72 and attaches to the removable panel 78 and to the inner sleeve upper panel 48 between the cutout 76 and window aperture 74. As shown in FIGS. 5 to 8, this forms a hinge 80 which allows the label to rotate through 180° from a position as shown in FIG. 6 wherein the removable panel 78 is received within the cutout 76 and the label indicia 72 are not visible through the window aperture 74, through the position shown in FIG. 7, to the position shown in FIG. 8 wherein the label indicia 72 becomes visible through the window apreture 74.
Returning to FIG. 2, cutouts 82 at the lateral side edges of the inner sleeve upper panel 48 near the sleeve open end 23, and additional cutouts 84 aligned therewith in the inner sleeve first and second side panels 56 and 58, provide access to the cassette 24 through the sleeve inner layer 26. Similar cutouts 86 are provided in the sleeve outer layer 28 in registry with the cutouts 82 and 84 to provide access to the cassette 24 through the entire sleeve 22.
FIGS. 2 and 4 best illustrate the structure of the sleeve outer layer 28. It is formed of folded pressboard stock, but of course could be formed of other folded stock material such as a suitable polymer, or could be molded or formed in some other fashion to form an equivalent structure to that disclosed here. Longitudinal fold lines 90 form a top panel 92, bottom panel 94, a first side panel 96 and a second side panel 98, which correspond to the sleeve inner layer 26, upper panel 48, lower pan 52, first side panel 56 and second side panel 58. The longitudinal fold lies 90 also form a glue flap 100 which seals to the first side panel 96 to form the three dimensional structure of the outer sleeve layer 28. Side tabs 102 and a foldable flap 104 form the closed end 25 of the sleeve outer layer 28. Of course, other closure means such as glue flaps may be substituted therefor. An arrow shaped aperture 106 and a rectangular window 108 in the top panel 92 register with the corresponding openings 60 and 74 in the sleeve inner layer 26. The rectangular window 110 in the second side panel 98 provides viewing for indicia 112 on the cassette 24.
A lateral fold line 114 at the forward end 116 of the bottom panel 94 forms a hinge 118 about which rotates a retaining flap 120. The retaining flap 120 extends from the fold line 114 to terminate in a tang 122; a terminal edge 124 of which engages the cassette 24 to retain the cassette 24 within the sleeve 22. An annular post 126 surrounds each of the piercing apertures 44 in the cassette 24 such that the aperture 44 extends axially through the post 126. The post has a vertical annular sidewall 128 against which the terminal edge 124 abuts. The retaining flap 120 performs a surprisingly good job of holding the cassette 24 within the sleeve 22. Even fairly vigorous shaking will not dislodge the cassette 24 from the sleeve 22.
A fresh cassette assembly 20 having its cells 32 filled with hydrogen peroxide is configured as follows: the cassette 24 is received within the sleeve inner layer 26. The label 70 is folded into the position shown in FIG. 8 wherein the label indicia 72 are visible through the window apertures 74 and 108. Also, the tab 62 is folded over 180° to face rewardly. The cells 32 are received within chambers within the cassette shell 30, the outer surface 132 of which is rounded. The tab 62 engages this rounded outer surface 132 to provide a certain degree of resistance to movement between the cassette 24 and the sleeve 22. The sleeve inner layer 26 is received within the sleeve outer layer 28 with the retaining flap 120 folded over the inner layer 26 and into the sleeve 22 where its terminal edge 124 abuts the annular post vertical wall 128 on the cassette 24 thereby retaining the sleeve inner layer 26 and the cassette 24 within the sleeve outer layer 28.
The cassette assembly 20 is intended for use with an automatic cassette extraction mechanism 134 as is shown in FIGS. 9 to 15. Turning to FIG. 9, the extraction mechanism 134 comprises a receiving slot 136 sized to receive the cassette assembly 20 with its sleeve open end 23 forward. The receiving slot 136 is outlined by a lower wall 138, an upper wall and two opposing sidewalls 142 (see also FIG. 15). A spring-loaded door 144 at an entrance 146 to the receiving 136 closes the receiving slot 136 when not in use and provides a downward biasing force against the cassette 24 to hold it firmly against the lower wall 138.
A bar code reader 148 is positioned above the lower wall 138 in such a fashion as to read the label indicia 72 as the cassette 24 is inserted into the receiving slot 136. A pressure switch senses the presence of a cassette 24 within the receiving slot 136. position sensing switch 150 engages the bar-code reader 148, and also engages an upper drive wheel 152 and a pair of lower drive wheels 154. If the bar code reader 148 fails to read the presence of a valid bar code label 70, then the drive wheels 152 and 154 will reverse to eject the cassette assembly 20 from the receiving slot 136. Assuming that the bar code reader 148 successfully reads the label 70, the label information, including lot code and shelf life data, will be fed to a control unit 156 for use in the sterilization control process. The control unit 156 is also operably connected to the position sensing switch 150 and the drive wheels 152 and 154 to control the label reading and cassette extraction process. Any suitable control unit may be employed, such as a microprocessor based automatic control system, and multiple controllers may be used for controlling various aspects of the operation described herein.
As is best seen in FIGS. 9 and 15, as the cassette assembly 20 is received into the receiving slot 136, a projection or opener 158 on the loading mechanism 134 slides between the cassette 24 and retaining flap 120 to rotate the retaining flap downwardly and out of engagement with the cassette 24. This allows the cassette 24 to slide outwardly of the sleeve 22. The opener 158 extends laterally from a bracket 160 and an edge 162 on the bracket 160 adjacent the opener 158 abuts forward edges 164 of the sleeve 22 to limit forward movement of the sleeve 22. A pair of spring clips 166 project laterally and slightly upwardly from the bracket 160. Each of the spring clips 166 has a upwardly extending lip 168 thereon which slides into the cut outs 82 and 86 of the sleeve inner layer 26 and outer layer 28, respectively, to hold the sleeve 22 firmly in position. With the cassette assembly 22 in this position, the lower drive wheels 154 also protrude through the cut outs 82 and 86 to engage the cassette lower housing 36, and the upper drive wheel 152 protrudes through the arrow shaped apertures 60 and 106 to engage the cassette upper housing 34. Thus, rotation of the drive wheels urges the cassette 24 outwardly of the sleeve 22 through its open end 23.
Resistance to movement between the cassette 24 and sleeve 22 provided by the tab 62 ensures that if the cassette assembly 20 is not already properly positioned against the bracket edge 162, the sleeve 22 will move forwardly with the cassette 24 until the sleeve 22 is properly in position. At this point, the resistance provided by the tab 62 can no longer restrain movement of the cassette 24 and it will move forwardly out of the sleeve 22.
Turning to FIG. 10, as the cassette 24 moves out of the sleeve 22, the springiness of the label 70 and the weight of the removable panel 78 urge the label 70 to hang downwardly about its hinge point 80. The cassette 24 then moves out of the extraction mechanism 134 and into a fluid handling system 170 such as is shown in FIG. 16, with the cassette extracts mechanism 134 removed for clarity. The fluid handling system 170 extracts the measured quantity of hydrogen peroxide from a cell 32 through the needle 42 (see FIG. 2A) to deliver it to a sterilization chamber 172 to sterile articles (not shown) contained therein. Operation of this mechanism is more fully described in the Wlliams et al. U.S. Pat. Nos. 4,817,800 issued Apr. 4, 1989; 4,913,196 issued Apr. 3, 1990; 4,938,262 issued Jul. 3, 1990; and 4,941,518 issued Jul. 17, 1990, all of which are incorporated herein by reference.
When spent, the cassette 24 returns from the fluid handling system 170 and the drive wheels 152 and 154 push it home into the sleeve 22, as shown in FIG. 11. As the cassette 24 moves into the sleeve 22, its rearward end contacts the label 70 causing it to rotate backwards to the position illustrated in FIG. 6 wherein the label indicia 72 are not visible exterior of the sleeve 22. Turning to FIG. 12, the cassette assembly 20 then moves outwardly of the receiving slot 136. The opener 158 slides out of the sleeve 22 thus allowing the retaining flap 120 to move upwardly into engagement with the cassette 24. The cassette assembly 20 is thus ejected from the receiving slot 136 with the cassette 24 firmly received with the sleeve 22.
Any drops of hydrogen peroxide solution which may remain on the outside of the cassette, although unlikely, would nevertheless be absorbed and retained by the sleeve inner layer 26 thereby protecting an operator therefrom. If the spent cassette is reinserted in to the receiving slot 136, the indicia 72 on the label 70 will not be visible due to the folding over of the label 70 during the cassette reinsertion. When the bar code reader 148 senses the lack of identifying indicia 72, the control unit 156 instructs the drive wheels 152 and 154 to immediately eject the cassette assembly 20. Of course, other actions can result in rejection of the cassette assembly 20. For instance, the control unit could be programmed to reject the cassette assembly if the bar code data indicates that the cassette assembly 20 has exceeded its shelf life, or if the lot code has previously been identified as rejected.
While the invention has been described with regard to a particular embodiment thereof, those skilled in the art will understand, of course, that the invention is not limited thereto since modifications can be made by those skilled in the art, particularly in light of the foregoing teachings. Reasonable variation and modification are possible within the foregoing disclosure of the invention without the departing from the spirit of the invention.
For example, the novel cassette assembly and handling techniques may be applied to other processes outside of sterilization. The techniques described herein have utility for handling a variety of cassettes, such as for example, cassettes containing reagents for chemical or medical tests. The contents of the cassette need not be liquid and the invention is not limited to any specific material or method of extracting such material from the cassette.
Further, other structures than presented herein may accomplish the teachings of the present invention. The retaining flap 120 need not face inwardly of the sleeve 22 to abut a surface on a face of the cassette. Instead, it could abut an end of the cassette, or could abut a surface on the sleeve, such as a folded-in lip on the edge of the sleeve opposite the flap 120 at the cassette open end. In this case, the spring in the material of the sleeve would hold the flap 120 in place.
Other means of providing resistance to movement between the cassette 20 and the sleeve 22 could substitute for the tab 62. For instance, rearwardly facing projections could be formed on the sleeve, or attached thereto.
While the adhesive label 70 in combination with the mass of the cut-out portion 78 disclosed above provides a convenient expedient for placing indicia 72 on the cassette assembly 20, other configurations may be substituted therefor. For example, the cut-out portion 78 stiffens the label 70, but other known means of providing a stiff label may be substituted therefor. The label may be formed of stiff stock in which case adhesive need only be applied at the attachment to the sleeve, other stiffening material could be attached thereto, and depending upon the materials of construction, the label may be attached by alternative means to adhesive. Alternatively, the cut-out portion 78 may be cut to form a natural hinge, as by cutting only three instead of four sides and the indicia may be printed directly onto the cut-out portion 78. Many expedients to providing a movable label will be appreciated by those of skill in the art upon examination of this specification.
Various modifications and alterations of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention. It should be understood that the invention is not limited to the embodiments disclosed herein, and that the claims should be interpreted as broadly as the prior art allows. | A method for delivering liquids is disclosed wherein a quantity of the liquid is provided within a cell within a cassette. The cassette is received within a sleeve having an open end. A flap at the open end of the sleeve extends inwardly through the open end between the sleeve and cassette to abut a lip on the cassette and hold the cassette therein. Impingement of the flap pushes the flap away from the lip to allow the cassette to move out of the sleeve. A label mounted within the sleeve rotates between a viewable position where it is visible through a window in the sleeve and a retracted position away from the window. Extraction and reinsertion of the cassette into the sleeve moves the label from the viewable to the nonviewable position. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Priory application: RU2003132127, filing dated Nov. 4, 2003;
PCT/RU2004/000094, filing date Mar. 12, 2004.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0003] Not applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
[0004] Not applicable.
BACKGROUND OF THE INVENTION
[0005] The invention is applied to scintillation materials and may be used in nuclear physics, medicine, and oil industry for recording and measuring of X-ray, gamma- and alpha- radiation; non-destructive testing of solid state structure; three-dimensional positron-electron computer tomography (PET) and X-ray computer fluorography. The relevance of the invention is that in fluoroscopy, X-ray computer tomography and PET, an introduction of new/improved scintillators has resulted in significant improvement of the image quality or/and reduced the measuring time. (“Inorganic scintillators in medical imaging detectors” Carel W. E. van Eijk, Nuclear Instruments and Methods in Physics Research A 509 (2003) 17-25).
[0006] The known scintillation substance is a lutetium oxyorthosilicate powder doped with cerium Lu 1.98 Ce 0.02 SiO 5 (A. G. Gomes, A. Bril “Preparation and Cathodoluminescence of Ce 3+ activated yttrium silicates and some isostructural compounds”. Mat. Res. Bull. Vol. 4, 1969, p. 643-650). This phosphor was created for an application in the cathodoluminescence devices, however this substance may be utilized also for the X-ray, gamma- and alpha-ray emissions recording.
[0007] It is known the scintillation substance/crystal of cerium doped lutetium oxyorthosilicate Ce 2x Lu 2(1−x) SiO 5 , where x is varied between the limits from 2×10 −4 to 3×10 −2 (U.S. Pat. No. 4,958,080, Sep. 18, 1990). The crystals of this composition are grown from a melt having composition of Ce 2x Lu 2(1−x) SiO 5 . In scientific literature abbreviated name LSO:Ce is wide used for denotation of this crystal. The Ce 2−x Lu 2(1−x) SiO 5 scintillation crystals have a number of advantages in comparison with other crystals: a high density, a high atomic number, relatively low refractive index, a high light yield, a short decay time of scintillation. The disadvantage of known scintillation material is the large spread of important characteristics of scintillation, namely, a light yield and an energy resolution, from crystal to crystal. The experimental results of systematic measurements of commercially produced LSO:Ce crystals grown by CTI Inc. company (Knoxville, USA) clearly display this (U.S. Pat. No. 6,413,311, Jul. 2, 2002). Another disadvantage is a significant reduction of light yield, when the containing LSO:Ce crystal device is operated under conditions when the temperature is above a room temperature, for example, in petroleum industry for the rock composition analyses in a borehole during the search of the new deposits. Another disadvantage of LSO:Ce crystals is an afterglow effect, that is the prolonging fluorescence after radiation exposure, for example, the luminescence intensity of the samples described in U.S. Pat. No. 4,958,080 is reduced to decibels during ten minutes.
[0008] It is known the scintillation substance the lutetium oxyorthosilicate containing cerium, Ce:Lu 2 SiO 5 , in the form of a transparent ceramics. The Lu 2 SiO 5 :Ce scintillator is formed into ceramics material through sintering the Lu 2 SiO 5 :Ce powder. Because the Lu 2 SiO 5 :Ce has a monoclinic structure rather than a cubic crystalline structure, the sintering produces a translucent ceramics rather than transparent. The cerium-doped lutetium orthosilicate is formed into a transparent glass scintillator by combining the silicate oxide, lutetium oxide, cerium oxide, potassium oxide, and barium oxide. The pores between the particles are removed which results in a consolidation of the scintillator material. As a result, the translucent ceramics is converted into a transparent ceramics applicable for using in the medicine tomographs (U.S. Pat. No. 6,498,828 from Dec. 24, 2002). The drawback of patent proposed is a quality of scintillation ceramics, which is made from, so-named, stoichiometric composition of lutetium oxyorthosi-licate mixture, a stoichiometric composition is characterised by ratio of formula units of (Lu+Ce)/Si is equal exactly to 2/1. Since the congruent composition of lutetium oxyorthosilicate does not coincide with stoichiometric one, the ceramics of stoichiometric composition apparently contains the components of oxides which did not react completely as a results the scattering centers are formed. The light yield is an important characteristic of a scintillator. The presence of scattering centers reduces a light yield appreci-ably. A transparent ceramics made from a cerium-doped gadolinium oxyorthosilicate has the same limi-tation (W. Rossner, R. Breu “Luminescence properties cerium-doped gadolinium oxyorthosilicate cera-mics scintillators” Proc. Int. Conf. on Inorganic Scintillators and Their Application, STINT'95, Netherlands, Delft University, 1996, p. 376-379). The scintillation elements fabricated from the transparent ceramics have the 60% less light yield than the elements fabricated from the Ce:Gd 2 SiO 5 crystals.
[0009] Presence of an afterglow is very unwanted effect for some applications, for example, for an imaging system, in which the electronic part of device indicates a photon flux from the scintillation elements absorbing the gamma radiation. The afterglow effect, i.e. a photon flux from the scintillation element does not exposed to gamma radiation, reduces a contrast range, a sensitivity and a precision of device. The afterglow impairs also the parameters of medical devices based on the utilization of positron emitting isotopes, for example, the three-dimensional medical tomographs (Fully-3D PET camera) for diagnostic of the cancer diseases, and, especially, for the MicroPET systems designed for testing of the new medicines. A principle of operation of the three-dimensional medical tomographs is that the microscopic concentration of substance containing an emitting positron isotope is introduced into the blood of a patient. This substance is accumulated in the cancer cells of patient. An emitted positron annihilates instantly with an electron this results in the emission of the two 511 KeV energy gamma-quantums scattering exactly in opposite directions. In tomograph the detection of both gamma-quantums occurs by means of the several ring detectors each of which contains hundreds of the separate crystalline scintillation elements. The high Ce:LSO density gives an effective absorption of all gamma quantums emitting from a body of patient examined. A location of the atom of a radioactive isotope in a patient body is determined by means of a time detection of both gammas and numbers of scintillation elements indicated these gamma quantums. In a patient body a part of gamma quantums is scattered because of Compton effect, as a result, the detection of gamma quantums occurs by the crystalline scintillation elements do not arranged in line. Therefore if an scintillation element has a strong afterglow then the indicating system may recognise it as a result of annihilation at a moment, however, actually, this detection is a consequence of exposure to gamma quantum radiation in previous moment of measuring. In the three-dimensional medical tomographs of regular resolution the several thousands 6×6×30 mm 3 scintillation elements are used, they maintain the 6×6×6=216 mm 3 volume three-dimensional resolution. Even a strong afterglow of the Ce:LSO crystals does not lead up to the considerable consequences when the comparatively thick 6×6 mm 2 cross-section elements are used for a diagnostics of the cancer illnesses, because a desired recording accuracy may be achieved by an injection of the large doses of radioactive substances or by a reducing of the rate of translation of patient through tomograph's ring.
[0010] However condition is changed sharply for MicroPET, which are used for a study of the life processes in vivo, especially, in a human brain or for a measuring of a distribution of medicines in a animal body (mouse, rats) during testing of the new medicines. For MicroPET systems it is necessary to use the devices with a maximal space resolution. The 1×1 mm 2 sectioned and even 0.8×0.8 mm 2 sectioned scintillation elements are used just now. The 1 mm 3 space resolution is achieved. Because of so small thickness of elements the numerous gamma quantums may cross direct the several scintillation elements at different angles. Consequently, to calculate which part of a scintillation radiation is induced by some or other gamma quantum is a complicate technical task. In this case an afterglow becomes a very undesirable effect, because it reduces an accuracy all system.
[0011] The afterglow and thermoluminescence phenomena are explored circumstantially for the Ce:LSO crystals (P. Dorenbost, C. van Eijekt, A. Bost, Melcher “Afterglow and thermoluminescence properties of Lu 2 SiO 5 :Ce scintilation crystals”, J. Phys. Condens. Matter 6 (1994), pp. 4167-4180). According to this article an afterglow is observed both in the crystals having a high light yield and a low light yield, and a conclusion is that an afterglow is a property immanent to the Ce:LSO substance.
[0012] It is known substance the cerium doped gadolinium oxyorthosilicate, Ce 2y Gd 2(1−x−y) A 2x SiO 5 , where A is at least one element selected from the group La (lanthanum) and Y (yttrium), the x and y values are varied within the limits 0<x<0.5 and 1×10 −3 <y<0.1 (U.S. Pat. No. 4,647,781, Mar. 3, 1987). The main limitation of this group of scintillation crystals is a low light yield in comparison with the Ce-doped lutetium oxyorthosilicate, Ce 2x Lu 2(1−x) SiO 5 , described above.
[0013] The known method of crystal growing of the large size Ce-doped lutetium oxyorthosilicate, Ce:LSO, is described in the U.S. Pat. No. 6,413,311, where the Ce:LSO boules up to 60 mm in diameter and 20 cm long are grown by Czochralski technique. An appreciable demerit of these large-sized Ce:LSO boules is that a light yield is strongly differed even within a boule, decreasing to 30%-40% from a top to a bottom of a boule. Furthermore, a scintillation decay time (a time of luminescence) may be varied over the wide range of values from 29 nanoseconds to 46 nanoseconds, at that an energy resolution value may fluctuate within the 12%-20% limit. Such a large spread in performance leads up to necessity during an industrial production to grow a large number of boules by Czochralski method, to cut them into parts (packs), to test each pack and on the basis of such tests to select the packs which possibly to utilize for fabrication of scintillation elements for medical tomographs.
[0014] It is known the scintillation crystals, LU 2(1−x) Me 2x Si 2 O 7 , where LU is lutetium-based alloy which also includes one or more of Sc, Yb, In, La, Gd; where Me is Ce or cerium partially substituted with one or more of the elements of the lanthanide family excluding lutetium; and where x is defined by the limiting level of LU substitution for Me in a monoclinic crystal of the lutetium pyrosilicate structure (U.S. Pat. No. 6,437,336). The crystal is formed by crystallization from a congruent molten composition of LU 2(1−x) M 2x Si 2 O 7 , a congruent composition allows to use up to 80% of initial melt, and the crystals exhibit reproducible scintillation response to gamma radiation, a light yield spread over volume of boule did not exceed 20% and this commercial parameter was significantly better than for Ce:LSO crystals. However, the Lu 2(1−x) Me 2x Si 2 O 7 crystals appreciably concede to the Lu 2 SiO 5 crystals in the basic scintillation parameters, namely, the light yield and density. Thus the lutetium oxyorthosilicate crystals, Ce:LSO, are a more preferable scintillator for utilization in a three-dimensional positron-electron tomography, because a tomograph based on these crystals is a more sensitive and, in consequence, a dose of radioactive medicaments, adding in the blood of a patience on early stage of cancers, is reduced.
[0015] It is known the lithium containing scintillation substance of the cerium doped yttrium silicate of chemical formula LiYSiO 4 , (M. E. Globus, B. V. Grinev “Inorganic scintillators”, publishing house ‘AKTA’ Kharkov, (2000) p. 51). The 5% Ce 3+ -doped LiYSiO 4 crystal has a peak of luminescence at 410 nm, a luminescence time constant is equaled to 38 ns and a maximal light yield at detection of gamma quantums is 10000 photons/Mev, this value is two and half time less than for the known lutetium oxyorthosilicate scintillating crystals, Ce 2−x Lu 2(1−x)SiO 5 . A low efficient detection of gamma radiation is resulted from a low density of scintillator is equaled 3.8 g/cm 3 . This substance may be utilized for detection of neutron radiation, however material is a low efficient for a gamma radiation.
[0016] It is known the lithium containing scintillation substance of the cerium doped lutetium silicate of chemical formula LiLuSiO 4 , (M. E. Globus, B. V. Grinev “Inorganic scintillators”, publishing house ‘AKTA’ Kharkov, (2000) p. 51). The 1% Ce 3+ -doped LiLuSiO 4 crystal has a peak of luminescence at 420 nm, a luminescence time constant is equaled to 42 ns and a maximal light yield at detection of gamma radiation is about 30000 photons/Mev, this value is 10% higher than for the known lutetium oxyorthosilicate scintillating crystals, Ce 2−x Lu 2(1−x) SiO 5 . However, an essential limitation of given crystal is a low density equaled to 5.5 g/cm 3 . Such small density does not allow to use these crystals in three-dimensional tomographs (Fully-3D PET camera) and, especially, for MicroPET systems, because the basic requirement for scintillating crystal for these applications is an attenuation length of gamma radiation, which should be less then 1.5 cm (W. M. Moses, S. E. Derenzo “Scintillators for positron emission tomography”, Conference SCINT'95, Delft, The Netherlands (1995), LBL-37720). This parameter is equaled 2.67 cm for crystal having a density of 5.5 g/cm 3 , whereas for the Ce 2−x Lu 2(1−x) SiO 5 crystal of 7.4 g/cm 3 density an attenuation length is equaled 1.14 cm.
[0017] The Ce:LiYSiO 4 and Ce:LiLuSiO 4 crystals can not be recognised as a prototype for any variants of the given invention, because they are differed both a chemical formula and a crystal structure, which defines a crystal density. A high crystal density is a basic parameter for the applications which are the aim of the given invention.
[0018] The chemical formulae of the given invention are the numerous crystals of the solid solutions on the basis of the silicate crystal containing a cerium, Ce, and crystallising in the monoclinic syngony, spatial group B2/b, Z=4, and crystallising in a hexagonal syngony of apatite structural type with a spatial group P6 3 /m, Z=1.
[0019] It is known the mono-cation cerium silicate crystallising in an apatite-brytolite structural type, Ce 9.33 □ 0.67 (SiO 4 ) 6 O 2 , where □ is a cation vacancy (A. M. Korovkin, T. I. Merkulyaeva, L. G. Morozova, I. A. Pechanskaya, M. V. Petrov, I. R. Savinova “Optical and spectral-luminescence properties of the orthosilicate crystals of lanthanide” Optics and Spectroscopy, value 58, issue 6 (1985) p. 1266-1269) and the double silicate of cerium, LiCe 9 (SiO 4 ) 6 O 2 , (I. A. Bondar, N. V. Vinogradova, L. N. Dem'yanets et al. “Silicates, germanates, phosphates, arsenates, and vanadates. Chemistry of rare elements” monograph M. Nauka, (1983) 288 p.). A cerium presents in the Ce 9.33 □ 0.67 Si 6 O 26 □LiCe 9 Si 6 O 26 crystals, however, a luminesce completely quenched in them, this is explained by a concentration quenching in consequence of high concentration of cerium ions in crystals. These crystals are not applicable for utilization as a scintillator. An analogue of the substance claimed in the items 16 , 17 , 18 of given invention is a crystal of mono-cation cerium silicate, Ce 9.33 □ 0.67 Si 6 O 26 , since it has the same symmetry, P6 3 /m, Z=1, and has a closest composition to the variants aforecited. An analogue of the substance claimed in the items 19 , 20 , 21 of given invention is a crystal of double cerium silicate, LiCe 9 Si 6 O 26 , since it has the same symmetry, P6 3 /m, Z=1, and has a closest composition to the variants aforecited. Both the Ce 9.33 □ 0.67 Si 6 O 26 crystal and the LiCe 9 Si 6 O 26 crystal cannot be accepted as prototypes for each variant of scintillation substance of given invention since they are not a scintillation material, i.e. these crystals do not have a generic character of given invention reflecting a purpose.
[0020] A computer search of chemical compounds in the international X-ray library's database (PDF Database, International Center for Diffraction Data, Newton Square, Pa., U.S.A.) has shown that the individual chemical compounds on a basis mono-cations and doubles silicates, R 9.33 □ 0.67 (SiO 4 ) 6 O 2 and LiR 9 Si 6 O 26 , respectively, where R═La, Sm, Nd, Gd, Ce are known. However, to our knowledge, there are no patents or publications in which these compounds were additionally doped with cerium what is necessary for an initiation of scintillation properties. Therefore the R 9.33 □ 0.67 (SiO 4 ) 6 O 2 and LiR 9 Si 6 O 26 substances, where R═La, Gd or their mixture, it is necessary to consider as an utilization of known substance on a new purpose.
[0021] The nearest analogue chosen as a prototype for all variants of the claimed scintillation substance, is a scintillation substance (variants) patented in the 2157552 patent, Russia, and the U.S. Pat. No. 6,278,832, USA. The chemical formulae of this invention represent the numerous crystals of solid solutions of oxyorthosilicate crystal, including cerium, Ce, and crystallising in the Lu 2 SiO 5 structural type with space group B2/b, Z=4, which composition is represented by the chemical formula Ce x Lu 1 A 1−x SiO 5 , where A is Lu and at least one element selected from the group consisting of Gd, Sc, Y, La, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb. Other elements of periodic table can be occurred in a crystal as the impurities in the starting oxides or can be introduced into composition during a crystal growth or in a result of annealing in a special atmosphere. Partially the similar results are achieved in the U.S. Pat. No. 6,323,489. This patent protects the lutetium-yttrium oxyorthosilicate crystal of composition having the chemical formula Ce x Lu 2−x−z Y x SiO 5 , where 0.05<x<1.95 and 0.001<z<0.02. The main disadvantage of the above mentioned inventions is the use only molar ratio equaled to 50% Lu 2 O 3 /50% SiO 2 =1 of starting oxides for all patented scintillation materials, that corresponds exactly to stoichiometric composition of Lu 2 SiO 5 structure. For all mixed crystals simultaneously containing several rare-earth ions, the ratio of 50% of the mix of different elements and 50% of SiO 2 has been used. This composition does not allow to grow by Czochralski method the large commercial (diameter more than 80-100 mm) containing lutetium and Ce-doped crystals having a high uniformity of scintillation parameters on all volume of boule. Additionally, the crystals of stoichiometric composition cracked when being sawed for scintillation elements, for example, in the size of 0.8×0.8×10 mm 3 . Another essential disadvantage of specified scintillation materials is the presence of oxygen vacancies which increase a light output and reduce a probability of cracking of the boules at sawing, however, simultaneously, the presence of oxygen vacancies in two- four times increases an intensity of afterglow (thermoluminescence) after gamma-radiation of scintillation material.
[0022] Another confirmation of basic drawback of composition characterised by the 50% Lu 2 O 3 /50% SiO 2 molar ratio of oxides is the information described in U.S. Pat. No. 5,660,627. This patent protects a method of growing of lutetium orthosilicate crystal with a plane front of crystallization by Czochralski method from a melt of Ce 2x Lu 2(1−x) SiO 5 chemical formula, where 2×10 −4 <x<6×10 −2 . The gamma luminescence spectra of crystals grown with a conical front of crystallization and with a plane front of crystallization have the strong, fundamental differences both in a shape and in a position of maximum of luminescence. So the appreciable differences result from the composition of the initial melt, which has the 50% Lu 2 O 3 /50% SiO 2 mole ratio of main components. A crystal growing from this melt has a composition differed from the composition of melt, the gradient of concentration is observed along a crystal cross-section, and the real Ce 2x Lu 2(1−x) /Si ions ratio is differed from the ratio of 2/1=2 formula units. For the confirmation of the aim declared in the U.S. Pat. No. 5,660,627 the crystals 26 mm in diameter were grown at the 0.5 mm/hour and 1 mm/hour rates, however, even at these very advantageous growth parameters, the crystals grown with a conical crystallization front can not be used for the commercial applications because of cracking and spread of scintillation performance.
[0023] For many years the growing of crystals with a planar crystal-melt interface by Czochralski method is used for commercial production of optical and piezoelectric materials, that is described in detail in the hundreds of papers in scientific journals and books. The well known commercial lithium metaniobate crystal (R. L. Byer, J. F. Young “Growth of High-Quality LiNbO 3 Crystals from the Congruent Melt” Journal of Appl. Phys. 41, N6, (1970), p. 2320-2325) is being grown by Czochralski method from a melt of congruent composition, Li 0.946 NbO 2.973 . Having the ratio of initial oxides is equaled to Li 2 O/Nb 2 O 5 =0.946, the congruent composition is differed from an ordinary, stoichiometric composition of lithium metaniobate, LiNbO 3 , where a ratio of component is equaled to 50% LiO/50% Nb 2 O 5 =1. (P. Lerner, C. Legras, J. Dumas “Stoechiometrie des mohocristaux de metaniobate de lithium”, Journal of Crystal Growth, 3,4 (1968) p. 231-235). An existence of non-stoichiometric compounds is directly concerned with a structure of real crystal, in which the vacant lattice sites exist, and the excess atoms of one of the elements are placed in the crystal interstitial sites. (P. V. Geld, F. A. Sidorenko “Dependence of physical-chemical properties of non-stoichiometric compounds on structure of short-range order” Izvestia AN SSSR, seria Inorganic materials, 1979, v. 15, #6, p. 1042-1048). As a result, a ratio of components forming a structure does not correspond to the whole-numbered indices, and the chemical formulae of such compounds are described by the fractional numbers. A chemical composition is named the congruent composition, if a composition of melt is coincided with a composition of crystal growing from this melt. All the physical and mechanical properties of crystals grown from the melts of congruent compositions maintain the values constant over all volume of boule. For some applications a near stoichiometric composition, Li 2 O/Nb 2 O 5 =1, is a preferable use, U.S. Pat. No. 6,464,777B2 dated Oct. 15, 2002. This patent clearly illustrates as the small variations of crystal composition lead up to the appreciable alterations of physical properties of crystal and this is important for the practical applications.
[0024] It is known (in the book D. T. J. Hurle “Crystal Pulling from the Melt” Springer-Verlag, Berlin, Heidelberg, New-York, London, Paris, Tokyo, Hong Kong, Budapest, 1993, p. 21) that because of the complex oxide systems of optics and electronics interests, such as garnets and spinels, do not correspond to a congruently melting composition it is necessary to induce growth only at a very low rate in order to give time for diffusion away from the interface of the excess component. Failure to do this leads to dramatic degradation in the perfection of the crystals due to the occurrence of constitutional supercooling. A search of congruent composition or very near to congruent composition is an important stage of development of commercial production of all optical materials, however, the authors of given invention do not know the data about congruent composition (or near to congruent composition) of lutetium oxyorthosilicate published in the scientific journals or in the patents. All known publications are dedicated to the crystals, in which a ratio of formula units, (Ce 2x +Lu 2(1−x) )/Si, is exactly equaled to 2/1.
[0025] Generalising the above-mentioned, we may conclude that a basic technical drawback, immanent to both the known scintillation crystals on the basis of lutetium orthosilicate, Ce x Lu 2−x SiO 5 , and prototype's crystals and a method of making of these crystals, are a longitudinal heterogeneity of optical quality of grown crystals, a heterogeneity of the basic scintillation parameters both in a bulk of boule grown by Czochralski method and heterogeneity from boule to boule grown in alike conditions and, at last, a low growth rate. These drawbacks substantially arise from the use in Czochralski method of melt having a composition which characterised a ratio of formula units, (Ce+Lu)/Si, which is exactly equaled to 2/1, i.e. the reason of these drawbacks resides in a non-congruent composition of melt. At the existence of congruent point, a crystal growth from a stoichiometric composition leads up to that the segregation coefficients of both the host crystal components, Lu, Si, and the additional component, Ce, are differed from unit, and, moreover, a crystal composition is shifting from the congruent point as a crystal pulling, that results in dramatic degradation of crystal quality despite on the extremely low growth speed. A segregation coefficient of component is a ratio of component's quantity in a crystal to component's quantity in a melt. Another common technical demerit of scintillation crystals on the base of lutetium orhtosilicate is the large losses of crystalline material because of cracking during slicing of a large, up to 60 mm in diameter, boules into 1 mm thickness pieces, which in their turn are cut into rods to produce the 1×1×10 mm 3 dimensions elements in the quantity of several tens of thousands pieces needed for assembling of one tomograph.
BRIEF SUMMARY OF THE INVENTION
[0026] A task of the given invention is a creation of a new scintillation material and a method of its making. The given invention is directed on the solution of task of mass production of the large crystalline boules of scintillation materials grown by directional crystallization method. Scintillation materials should have a large density; a high light yield and a homogeneity of scintillation properties at mass production; reducing of manufacturing cost of finished scintillation elements due to small losses of crystalline substance at mechanical treatment; decreasing of time and afterglow intensity of elements having an optimal chemical composition of crystals. Stepanov's method allows to produce the scintillation substances in the form of crystalline rods of specified size including the elements having a square form of cross-section and, therefore, to exclude an expansive slicing of massive crystal. A method of production of scintillation translucent or transparent ceramics in the form of rectangular rods and plates allows also to eliminate expansive losses of scintillation substance during cutting of crystalline boule. Thus, the given invention presents the group of inventions and provides an attainment of several technical results on the basis of different variants of scintillation substances of both crystals and the ceramics, having a high density and representing the rare-earth silicates of different chemical formulae.
[0027] The technical task solved by offered group of inventions is a production of large crystalline boules, having a high light output of a luminescence over all volume, grown by directional crystallization method, in particular, the Kyropoulas and Czochralski methods, and also the task of the invention is a reproducibility of scintillation properties of monocrystals grown at mass production.
[0028] The first technical task in the specific forms is a composition of scintillation substance having an intensity and an afterglow time less than the known lutetium oxyorthosilicate crystals have, and a light output of proposed substance is comparable or higher than a lutetium oxyorthosilicate has.
[0029] The second technical task in the specific forms is a small percent of losses of valuable scintillation elements because of cracking during sawing and manufacturing of scintillation elements for the three-dimensional positron-emitting tomographs. In particular, for the high space-resolved medicine devices, for example, for recording positron-emitting isotopes placed in the alive biological objects (micro-tomographs—MicroPET), the elements of 1×1×20 mm 3 or 0.8×0.8×10 mm 3 dimensions are required.
[0030] The third technical task in the specific forms is the method of growing of scintillation monocrystals by directional crystallization method. The term (<<a directional crystallization>> denotes any method of single crystal growth method, including Czochralski method, Kyropoulas method, Bridgman method and others known methods.
[0031] The solutions of said tasks are achieved due to the use of scintillation substances both crystal and ceramics having the compositions on the basis of ten variants of substances unified by the common structural types, the chemical formulae and the method of fabrication of these materials.
[0032] Variant #1. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the first variant of given invention a new is a composition of substance is represented by the chemical formula
Ce x Lu 2+2y−x Si 1−y O 5+y ,
x is a value between 1×10 −4 f.u. and 0.02 f.u., y is a value between 0.024 f.u. and 0.09 f.u.
[0035] The technical result—the creation of scintillation substance having a large density; a high light yield and a homogeneity of scintillation properties during mass production is achieved due to the use of the substance based on a silicate having the congruent composition of basic components.
[0036] A technical result in the specific forms of implementation is achieved by way of using a scintillation substance, characterised in that the composition of the substance in the form of a single crystal is represented by the chemical formula
Ce x Lu 2.076−x Si 0.962 O 5.038 ,
x is a value between 1×10 −4 f.u. and 0.02 f.u.
[0037] Another technical result, namely mass production of large crystalline boules, having a high light output of a luminescence over all boule volume, a reproducibility of scintillation properties of monocrystals, is achieved by method of making of scintillating material. A single crystal is being grown by a directional crystallization method from a melt made from the charge of the composition defined by the 51.9% (Lu 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 oxides mole ratio.
[0038] The particular specific forms of invention implementation the technical result, expressed in a de-creasing of production cost of scintillation elements and a reproducibility of physical properties of the samples from boule to boule at mass production, is achieved by way of a growing of single crystal by Czochralski method and a growing of crystal by Kyropoulas method. A new in the given method is the single crystal being grown by Czochralski method and also Kyropoulas method from a melt made from the charge of the composition defined by the 51.9% (Lu 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 =1.079 oxides mole ratio, this is, so named, a congruence composition. In that oxides ratio the composition of grown crystal is equaled to composition of a melt, this circumstance allows to grow the crystals of more homogeneous in composition and in physical characteristics, than the crystals grown from a melt of stoichiometric com-position, 50% (Lu 2 O 3 +Ce 2 O 3 )/50% SiO 2 =1. A growth of crystals from a melt of congruent composition allows to use more than 80% of melt, this appreciably cheapens a cost of scintillation elements.
[0039] Variant #2. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the second variant of given invention a new is a composition of substance is represented by the chemical formula
Ce x Lu 2+2y−x−z A z Si 1−y O 5+y ,
where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb, Ca,
x is a value between 1×10 −4 f.u. and 0.02 f.u., y is a value between 0.024 f.u. and 0.09 f.u., z is a value between 1×10 −4 f.u. and 0.05 f.u.
[0043] The technical result—the creation of scintillation substance having a comparatively low cost, a high light yield and a homogeneity of scintillation properties, is achieved due to the use of the substance based on a silicate having the congruent composition of the total basic components, (Lu+A+Ce) and Si. The substitution of heavy expensive lutetium for at least one comparatively light element selected from the Gd, Sc, Y, La, Eu, Tb, Ca group reduces a manufactory cost, reduces a crystal cracking during an after growth annealing and a cutting, increases a light yield, but may cause an inconsiderable decreasing of density. The cheap scintillation crystals having a smaller density of 7.2-7.4 g/cm 3 , and atomic number of Z=58-63, but a high light yield are useful for numerous applications, for example, in nuclear industry.
[0044] A technical result in the specific forms of implementation is achieved by way of using a scintillation substance, characterised in that the composition of the substance in the form of a single crystal is represented by the chemical formula
Ce x Lu 2.076−x−z A z Si 0.962 O 5.038 ,
where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb, Ca,
x is a value between 1×10 −4 f.u. and 0.02 f.u., z is a value between 1×10 −4 f.u. and 0.05 f.u.
[0047] In the specific forms of implementation the detailed technical result, expressed in an increasing of a light yield following by an insignificant decrease of density is achieved by the growing of a scintillation substance, characterised in that the composition of the substance in the form of a single crystal is represented by the chemical formula
Ce x Lu 2.076−x−m−n La m Y n Si 0.962 O 5.038 ,
x is a value between 1×10 −4 f.u. and 0.02 f.u., m is a value does not exceeding 0.05 f.u., n is a value between 1×10 −4 f.u. and 2.0 f.u.
[0051] Another technical result—mass production of large crystalline boules, having a high light output of a luminescence over all boule volume, a reproducibility of scintillation properties of monocrystals grown during mass production, is achieved by way of growing of scintillating single crystal by a directional crystallization method from a melt made from the charge of the composition defined by mole ratio of oxides 51.9% (Lu 2 O 3 +A 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 , where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb.
[0052] The particular specific forms of invention implementation the technical result, expressed in a decreasing of production cost of scintillation elements, reducing a crystal cracking during an after growth annealing and a cutting, and a reproducibility of physical properties of the samples from boule to boule at mass production, is achieved by way of a growing of single crystal by Czochralski method and a growing of crystal by Kyropoulos method. A new in the given method is the single crystal being grown by Czochralski method and also by Kiropoulas method from a melt made from the charge of the composition defined by mole ratio of oxides 51.9% (Lu 2 O 3 +A 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 , where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb, Ca.
[0053] Variant #3. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the third variant of given invention a new is a substance containing a lithium, Li, in the quantity does not exceeding 0.25 f.u., and the composition of substance is represented by the chemical formula
Ce x Li q+p Lu 2−p+2y−x Si 1−y O 5+y−p ,
x is a value between 1×10 −4 f.u. and 0.02 f.u., y is a value between 0.024 f.u. and 0.09 f.u., q is a value between 1×10 −4 f.u. and 0.2 f.u., p is a value between 1×10 −4 f.u. and 0.05 f.u.
[0058] The technical result—the creation of scintillation substance having a high light yield, a large density, a homogeneity and reproducibility of scintillation properties during mass production is achieved due to the use of substance based on a silicate containing lithium and having the congruent composition of the basic components.
[0059] The technical result in the specific forms of implementation, expressed in a decreasing of production cost of scintillation elements and a reproducibility of physical properties of the samples from boule to boule at mass production, is achieved due to the use of the scintillation substance is characterised in that the composition of the substance in the form of a single crystal containing a lithium Li in the quantity does not exceeding 0.25 f.u. is represented by the chemical formula
Ce x Li q+p Lu 2.076−p−x Si 0.962 O 5.038−p ,
x is a value between 1×10 −4 f.u. and 0.02 f.u., q is a value between 1×10 −4 f.u. and o 0.2 f.u., p is a value between 1×10 −4 f.u. and 0.05 f.u.
[0063] Another technical result—mass production of large crystalline boules, having a high light output of a luminescence over all boule volume, a reproducibility of scintillation properties of monocrystals grown during mass production, is achieved by way of growing of scintillating single crystal grown by a directional crystallization method from a melt made from the charge of the composition defined by mole ratio of oxides 51.9% (Lu 2 O 3 +Li 2 O+Ce 2 O 3 )/48.1% SiO 2 .
[0064] Variant #4. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the fourth variant of given invention a new is a substance containing a lithium, Li, in the quantity does not exceeding 0.25 f.u. and its composition is represented by the chemical formula
Ce x Li q+p Lu 2−p+2y−x−z A z Si 1−y O 5+y−p ,
where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb,
x is a value between 1×10 −4 f.u. and 0.02 f.u., y is a value between 0.024 f.u. and 0.09 f.u., z is a value between 1×10 −4 f.u. and 0.05 f.u., q is a value between 1×10 −4 f.u. and 0.2 f.u., p is a value between 1×10 −4 f.u. and 0.05 f.u.
[0070] The technical result—the creation of scintillation substance having a comparatively low cost, reducing a crystal cracking during an after growth annealing and a cutting, a high light yield and a homogeneity of scintillation properties, is achieved due to the use of the substance based on a silicate having the congruent composition of the total basic components, (Lu+Li+A+Ce) and Si. The substitution of heavy expensive lutetium for at least one comparatively light element selected from the Gd, Sc, Y, La, Eu, Tb group reduces a manufactory cost, increases a light yield, but may cause an inconsiderable decreasing of density. The cheap scintillation crystals having a smaller density of 7.2-7.4 g/cm 3 , and atomic number of Z=58-63, but a high light yield are useful for numerous applications, for example, in nuclear industry.
[0071] A technical result in the specific forms of implementation is achieved by way of using a scintillation substance, characterised in that the composition of the substance in the form of a single crystal containing a lithium Li in the quantity does not exceeding 0.25 f.u. is represented by the chemical formula
Ce x Li q+p Lu 2.076−p−x−z A z Si 0.962 O 5.038−p ,
where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb,
x is a value between 1×10 −4 f.u. and 0.02 f.u., z is a value between 1×10 −4 f.u. and 0.05 f.u., q is a value between 1×10 −4 f.u. and 0.2 f.u., p is a value between 1×10 −4 f.u. and 0.05 f.u.
[0076] Another technical result—mass production of large crystalline boules, having a low cost, a high light output of a luminescence over all boule volume, a reproducibility of scintillation properties of monocrystals grown during mass production, is achieved by way of growing a single crystal by a directional crystallization method from a melt made from the charge of the composition defined by mole ratio of oxides 51.9% (Lu 2 O 3 +Li 2 O+A 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 .
[0077] Variant #5. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce)), in the fifth variant of given invention a new is a composition of substance represented by the chemical formula
Ce x Lu 9.33−x □ 0.67 Si 6 O 26 ,
x is a value between 1×10 −4 f.u. o 0.1 f.u.
[0079] The technical result—the creation of scintillation substance having a large density; a high light yield is achieved due to the making of the mono-cation silicate crystallized in a hexagonal syngony of apatite spatial group P6 3 /m, Z=1, as well as the expense of an advantageous content of Ce 3+ ions in the substance.
[0080] Variant #6. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the sixth variant of given invention a new is a substance containing a lithium, Li, and the composition of substance is represented by the chemical formula
Ce x Li q+p Lu 9.33−x−p □ 0.67 Si 6 O 26−p ,
x is a value between 1×10 −4 f.u. and 0.1 f.u., q is a value between 1×10 −4 f.u. and 0.3 f.u., p is a value between 1×10 −4 f.u. and 0.25 f.u.
[0084] The technical result—the creation of scintillation substance having a large density; a high light yield is achieved due to the making of the mono-cation silicate crystallized in a hexagonal syngony of apatite spatial group P6 3 /m, Z=1, as well as the expense of an advantageous content of Ce 3+ ions in the substance.
[0085] Variant #7. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the seventh variant of given invention a new is a substance containing a lithium, Li, and the composition of substance is represented by the chemical formula
Ce x Li q+p Lu 9.33−x−p−z □ 0.67 A z Si 6 O 26−p ,
where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb,
x is a value between 1×10 −4 f.u. and 0.1 f.u., q is a value between 1×10 −4 φ.e . o 0.3 f.u., p is a value between 1×10 −4 f.u. and 0.25 f.u., z is a value between 5×10 −4 f.u. and 8.9 f.u.
The technical result—the creation of scintillation substance having a large density, reducing a crystal cracking during an after growth annealing and a cutting, a high light yield is achieved due to the making of the mono-cation silicate crystallized in a hexagonal syngony of apatite spatial group P6 3 /m, Z=1, as well as the expense of an advantageous content of Ce 3+ ions in the substance.
[0090] Variant #8. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the eighth variant of given invention a new is a substance containing a lithium, Li, in the quantity one formula units and the composition of substance is represented by the chemical formula
Ce x LiLu 9−x Si 6 O 26 ,
x is a value between 1×10 −4 f.u. and 0.1 f.u.
[0092] The technical result—the creation of scintillation substance having a large density; a high light yield is achieved due to the making of the double silicate crystallized in a hexagonal syngony of apatite spatial group P6 3 /m, Z=1, as well as the expense of an advantageous content of Ce 3+ ions in the substance.
[0093] Variant #9. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the ninth variant of given invention a new is a substance containing a lithium, Li, in the quantity exceeding 1.0 f.u. and the composition of substance is represented by the chemical formula
Ce x Li 1+q+p Lu 9−x−p Si 6 O 26−p ,
x is a value between 1×10 −4 f.u. and 0.1 f.u., q is a value between 1×10 −4 f.u. and 0.3 f.u., p is a value between 1×10 −4 f.u. and 0.25 f.u.
[0097] The technical result—the creation of scintillation substance having a large density; a high light yield is achieved due to the making of the double silicate crystallized in a hexagonal syngony of apatite spatial group P6 3 /m, Z=1, as well as the expense of an advantageous content of Ce 3+ ions in the substance.
[0098] Variant #10. The known scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce), in the tenth variant of given invention a new is a substance containing a lithium, Li, in the quantity exceeding 1.0 f.u. and the composition of substance is represented by the chemical formula
Ce x Li 1+q+p Lu 9−x−p A z Si 6 O 26−p ,
where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb,
x is a value between 1×10 −4 f.u. and 0.1 f.u., q is a value between 1×10 −4 f.u. and 0.3 f.u., p is a value between 1×10 −4 f.u. and 0.25 f.u., z is a value between 5×10 −4 f.u. and 8.9 f.u.
[0103] The technical result—the creation of scintillation substance having a large density, reducing a crystal cracking during an after growth annealing and a cutting, a high light yield is achieved due to the making of the double silicate crystallized in a hexagonal syngony of apatite spatial group P6 3 /m, Z=1, as well as the expense of an advantageous content of Ce 3+ ions in the substance.
[0104] For all enumerated variants the presence of cerium ions, Ce 3+ , is a mandatory requirement, because a scintillation under gamma and X-ray radiation combines with luminescence originating from the Ce 3+ ion 5d → 2 F 5/2 transfer. For all variants of substances the maximum of Ce 3+ ion luminescence is in the blue 410-450 nm region of spectrum. This band is an optimal for detection of radiation with both the photomultiplier tubes and semiconductor radiation detectors. For measurements in that region the ordinary, commercial photomultiplier tubes having inexpensive glass input window are used, this reduces the cost of medical devices in comparison with devices in which the scintillation crystals, having an emission peak in ultraviolet region of spectrum, are utilized. A high quantum yield of cerium ions luminescence is also the representative indication of all crystals having the above-mentioned chemical formulas. The 5%-9% quantum yield characterizes which part of gamma-quantum energy is converted into Ce 3+ ions emission, and which part of energy (91%-95%)) is dissipated at thermal oscillations of lattice atoms. An essential scintillation parameter, a light yield depends directly on concentration of cerium, Ce 3+ , ions in a substance/crystal.
[0105] For all variants the lower limit for the cerium ions is determined by the fact that at the content of Ce 3+ in the quantity of less than 1 ×10 −4 f. units, the effectiveness of a scintillation luminescence of Ce 3+ becomes insignificant because of the small concentration. With the concentration of cerium lower than the above limit, the implementation of the technical task cannot be reached, namely it is not possible to achieve a light yield sufficient for practical utilization.
[0106] For practical applications the crystals having the higher cerium ions concentration are required because such crystals have appreciably higher light yield. However, the very high cerium concentration leads to the several negative results. Firstly, the crystals with a high cerium concentration have a bad optical quality, the scattering centers are presented in crystals. Secondly, a reducing of light yield is taken place because of both a lowering of optical quality and a decreasing of quantum efficiency, which happens due to an interaction of neighbour cerium ions, so named, an effect of concentration quenching of luminescence. Therefore the upper limit for cerium ions is set 0.02 f. units for all substances of given invention, which are crystallized in a monoclinic syngony, at the structural type Ce x Ln 2−x SiO 5 with a spatial group B2/b, Z=4. The upper limit of 0.1 f. units is set for the Ce x Ln 9.33−x □ 0.67 SiO 26 and Ce x LiLn 9−x SiO 26 substances being crystallized in a hexagonal syngony an apatite structural type with a spatial group P6 3 /m, Z=1. These limits are defined by experimentally. When the concentration is above indicated limits, then the formation of numerous scattering centers of light takes place during crystallization and, therefore, the implementation of such defective crystals in medical and technical devices is not possible.
[0107] The technical result, namely a production of large crystalline boules, having a high light output of a luminescence over all volume, a reproducibility of scintillation properties of monocrystals grown at mass production, a small percent of losses of valuable scintillation elements because of cracking during sawing and manufacturing of scintillation elements, is achieved due to the growing of scintillation crystals of congruency composition. The common improvement sign for the variants #1, #2, #3 and #4 is a value of ratio of rare-earth ions and silicon ions in chemical composition of substance, i.e. a composition characterized by a ratio of formula units of (Lu 2−x+2y+Ce x )/Si 1−y and (Lu 2−x+2y−z+ Ce x +A z )/Si 1−y is differed from a 2/1 ratio which is obligatory exactly equaled to 2 for all known scintillation substances on the basis of orthosilicates. For the substances of given invention the ratios of formula units of (Lu 2−x+2−y+ Ce x )/Si 1−y and (Lu 2−x+2y−z+ Ce x +A z )/Si 1−y are varied within the limit from 2.077 to 2.396 that corresponds to the mole oxides ratio equaled to 51.2% (Lu 2 O 3 +Ce 2 O 3 +A 2 O 3 )/48.8% SiO 2 =1.049 and 54.5% (Lu 2 O 3 +Ce 2 O 3 +A 2 O 3 )/45.5% SiO 2 =1.198, respectively. These magnitudes correspond to the compositions of substances Ce x Lu 2+2y−x Si 1−y O 5+y, Ce x Lu 2+2y−x−z A z Si 1−y O 5+y, Ce x Li q+p Lu 2+2y−x−z−p A z Si 1−y O 5+y−p, where variable y is changed within the limits from 0.024 f. units to 0.09 f. units. We have measured specified magnitudes using the commercial device for the electronic microanalysis (Cameca Camebax SX-50, operating at 20 kV, 50 mA and diameter of the beam of 10 microns), an accuracy of measurements of composition was ±0.003 f. units, in mole percents an accuracy was ±0.15 mol %. The mechanically polished samples for measurements were cut from the crystals grown by directional crystallization method from the melts having the mole ratios of components (Lu 2−x +Ce x )/Si and (Lu 2−x−y+Ce x +A z )/Si within the limits from 1.77 to 2.44. On the basis of X-ray phase analysis and measurements of melting point of series of powdered compositions, the authors of the given invention have defined the part of phase diagram for region of existence of lutetium oxyorthosilicate in the Lu 2 O 3 —SiO 2 system ( FIG. 1 ). The process of changing of composition of solid solutions of lutetium oxyorthosilicate crystals (phase “S”) in depending on a composition of melt is exhibited on FIG. 1 . In accordance with the traditional notations, a liquid phase is symbolized by “L” on this diagram. The maximum of melting point temperature of solid solutions “S” corresponds to the composition of 51.9 mol % Lu 2 O 3 +48.1 mol % SiO 2 on constitution diagram. The region of existence of phase “S” is surrounding by the fields of two-phase equilibrium L+S, Lu 2 O 3 +S and S+Lu 2 Si 2 O 7 .
[0108] The phase diagram ( FIG. 1 ) was detailed for the near equilibrium conditions of solidification during crystal growing from the melts having the different chemical compositions. The comparison of composition of initial melt with the composition of crystal grown from that melt determines that a solidification occurs in accordance with a liquidus and a solidus lines shown on FIG. 1 . The compositions of melts have been set at weighing of the initial chemicals, the temperatures of melts also were taking in account during experiments. The crystals growing were carried out at the conditions of low gradients of temperature and with the crystals pulling rates near 0.3 mm/hour, that maintained an attaining of the effective segregation coefficients of the Lu 3+ and Si 4+ ions between a melt and a growing crystal at the conditions near to equilibrium.
[0109] The liquidus and solidus lines on FIG. 1 show, that the lutetium oxyorthosilicate crystals may have the compositions characterized by the different ratio of initial Lu 2 O 3 and SiO 2 oxides, namely, a content of chemicals is within the range the 44.5-50.5 mol % for SiO 2 and the 55.5-49.5 mol % for Lu 2 O 3 . However, for the practical purposes the specified range of compositions is interested only partially, three compositions of melt denoted by the arrows numbered 1 , 2 , and 3 illustrate this. The arrow 1 denotes the 50% Lu 2 O 3 +50% SiO 2 composition of initial melt. It should be pointed out that the composition of crystal growing from this melt has the ratio of basic components less than 50.9 mol % Lu 2 O 3 /49.1 mol % SiO 2 =1.037. To grow the crystal of composition having the ratio of basic components equaled exactly to 50 mol % Lu 2 O 3 /50 mol % SiO 2 =1, it is required to use a melt of composition denoted by arrow 2 , i.e. the ratio of basic components in the melt is approximately equaled to 46 mol % Lu 2 O 3 +54 mol % SiO 2 =0.852.
[0110] An optimal composition of oxides mixture (a charge) for the growth of scintillation crystal of high quality in the conditions of the low temperature gradients (a large diameter of crucible) is the composition denoted by arrow 3 . In this case the segregation coefficients of basic components are equaled to a unity, and a composition of charge of melt coincides with the composition of growing crystal, both composition of charge and composition of grown crystal have the contents of basic components characterized by the mole ratio of 51.9% Lu 2 O 3 +48.1% SiO 2 =1.079.
[0111] Therefore, FIG. 1 shows the unique solution of technical task in the specific forms of implementations of first, second, third, and fourth variants describing the scintillation substances for the growing of oversize single crystals by Kyropoulos method, and also for the growing of big single crystals by Czochralski method utilizing the optimal composition of initial oxides having the mole ratio of 51.9% (Lu 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 , and the compositions of charge of melt and grown crystals coincide and are described by the chemical formula
Ce x Lu 2.076−x Si 0.962 O 5.038 ,
where x is a value between 1×10 −4 f.u. and 0.01 f.u.
[0113] The evidence of choice of the lower and upper values of the ratios range of the initial Lu 2 O 3 and SiO 2 oxides for the substances of variants #1, #2, #3 and #4 is illustrated on FIG. 1 . The lower limit of a components content in a crystal relative to a lutetium is determined by the oxides mole ratio of 51.2% (Lu 2 O 3 +Ce 2 O 3 )/48.8% SiO 2 =1.049, which corresponds to value of variable y=0.024 in a chemical formula of scintillation substance. The lower boundary is determined by an accuracy of the chemical and physical experimental methods of measurements of lutetium and silicon in a crystal. Such accuracy allows in a unique manner to distinguish the substances/crystals chemical compositions of the given invention from the compositions of known lutetium orthosilicate scintillation crystals having the 50% (Lu 2 O 3 +Ce 2 O 3 )/50% SiO 2 mole ratio of components.
[0114] The upper boundary of a components content in a crystal relative to a lutetium is determined by the oxides mole ratio of 54.5% (Lu 2 O 3 +Ce 2 O 3 )/45.5% SiO 2 =1.198, which corresponds to the value of variable y=0.09 in a chemical formula of scintillation substance. This boundary is determined experimentally. In a case of further increasing of a Lu 2 O 3 content in an initial melt and, consequently, in a crystal the scattering centers are occurred, that decreases a light yield, and, as a result, a technical result of given invention cannot be reached. After conversion of the values of compositions of the lower and upper boundaries into formula units for the #1, #2, #3, and #4 variants, the range of compositions in formula units defined by the ratios of (Lu 2−x +Ce x )/Si and (Lu 2−x−y +Ce x +A z )/Si is lying within the limit from 2.077 to 2.396. These values correspond to the compositions described by the chemical formulae Ce x Lu 2+2y−x Si 1−y O 5+y , Ce x Lu 2+2y−x−z A z Si 1−y O 5+y , and Li q Ce x Lu 2+2y−x−z A z Si 1−y O 5+y where y varies between the limits from 0.024 f. unites to 0.09 f. units.
[0115] Should make a point of the compositions of lutetium oxyorthosilicate solid solutions crystals, i.e. the compositions, which are to the right side from the maximum of their maximal melting point, FIG. 1 . This is a region of the crystal compositions lying to the right side bounded by a maximal SiO 2 solubility, corresponds to a solid solution composition having a molar ratio of 49.5% Lu 2 O 3 /50.5% SiO 2 =0.980, and a left boundary of crystal composition having the value of 50.9% Lu 2 O 3 /49.1% SiO 2 =1.037, is determined by the 50% Lu 2 O 3 +50% SiO 2 composition of melt, FIG. 1 .
[0116] Let us determine the crystals of which compositions may grow by a directional crystallization method from a melt obtained from a charge of the stoichiometric composition, 50% Lu 2 O 3 /50% SiO 2 =1.000, denoted by the arrow 1 on FIG. 1 . Depending on the technology peculiarities, namely the thermal conditions of a growing, the temperature gradients on a melt-crystal interface determining by a crystal diameter, the components segregation coefficients may vary from 1 to the equilibrium values which in its turn are determined in accordance with the constitution diagram FIG. 1 . As a result, from a charge of the stoichiometric composition of 50% Lu 2 O 3 +50% SiO 2 may grow the crystals of compositions being in the range bounded by the lower limit of a component ratio of more than 49.5% Lu 2 O 3 /50.5% SiO 2 =0.980, and the upper limit of a component ratio of less, than 50.9% Lu 2 O 3 /49.1% SiO 2 =1.037. In formula units this corresponds to the values range in which the variable y is more than (−0.01) ±0.003 f. units, but less than 0.018±0.003 f. units. The given range of the crystal compositions has not been patented in the known patents. However the given range cannot be a subject of new invention because the crystals having a composition in the given range are covered by a concept of existing state of the arts. These crystals do not maintain an improvement of technical performance in comparison with the known substances. A growing of a lutetium oxyorthosilicate crystal of high quality requires to use the congruent composition of melt, which appreciably differs from the composition of crystal growing from this melt. The crystals grown from a melt of stoichiometric composition have an appreciable variation of chemical composition along a length, and also an extremely large variation of all physical and scintillation parameters both along the length and diameter because the segregation coefficients of silicon and lutetium are differed from 1. Such crystals are utilized for the scientific researches, however a commercial production of crystals having a similar composition are of no interest because the percent of a chemical oxides-to-scintillation element yield is a low, a manufacturing cost is an extremely high.
[0117] In the specific forms of implementation the scintillation substances claimed in variants from the first to the fourth inclusive are achieved in the forms both a polycrystal/ceramics and a single crystal.
[0118] The manner of ceramics making by the method of hot-pressing, for example, the Gd 2 O(SiO 4 ):Ce scintillation ceramics is described, for example, in the paper (W. Rossner, R. Breu “Luminescence properties cerium-doped gadolinium oxyorthosilicate ceramics scintillators” Proc. Int. Conf. on Inorganic Scintillators and Their Application, STINT'95, Netherlands, Delft University, 1996, p. 376-379). In another manner of fabrication of high optical quality ceramics-scintillator the water solutions of Lu—Ce—A chlorides, where A is at least one of the elements of group Gd, Sc, Y, La, Eu, Tb, and the SiCl 4 liquid are used as the initial materials for a charge preparation. Into the mixture of said components a water solution of ammonium hydrocarbonate is added. Then the solution is being washed, filtered, and dried. The calcined at 1400° C. mixture of oxides is being stirred with a dissolvent and the fusible dopants, promoting a diffusion of atoms along grain boundaries on a stage of final high-temperature annealing. As the admixtures the numerous compounds not affecting a luminescence of cerium Ce 3+ ions can be used. After removing of organic components and trace of water the modified mixture is pressed in hydrostatic press at 2000 atmospheres. Then, during several hours, the pressed ceramics bars (rectangular or another form) are annealed in vacuum at temperatures 70°-150° C. lower the melting point of given ceramic composition. To remove the color centers and to improve an optical quality, the sintered bars is annealed in an oxygen containing atmosphere at final stage of processing. Such way a translucent ceramics-scintillator and a high optical quality ceramics are produced. A ceramics scintillation substance has a row of advantages in comparison with the single crystals, namely: an appreciable cheaper technology of scintillators production; ingot-to-scintillation element high product yield (no cracks); a saving up to 20%-50% of scintillation substance because of elimination of cutting from technology of fabrication of fine-face scintillation elements; a uniform distribution of cerium Ce ions in a polycrystal body; a shortening of scintillation elements processing time; any desirable shaping of scintillation elements.
[0119] In the specific forms of implementation a method of directional crystallization is used to make a scintillation substance in the form of single crystal. A new in a proposed method is that a single crystals are being grown by a directional crystallization method from the melts made from the congruent composition charges, the compositions are characterised by the oxides mole ratio of 51.9% (Lu 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 for the variant #1, the 51.9% (Lu 2 O 3 +A 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 for the variant #2, the 51.9% (Lu 2 O 3 +Li 2 O+Ce 2 O 3 )/48.1% SiO 2 for variant #3 and the 51.9% (Lu 2 O 3 +Li 2 O+A 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 for variant #4.
[0120] The specific peculiarities and the growth parameters of rare-earth silicates of stoichiometric composition for a directional crystallization method, in particular for Czochralski method are presented in article (C. D. Brandle, A. J. Valentino, G. W. Berkstresser “Czochralski growth of rare-earth orthosilicates (Ln 2 SiO 5 ), J. Crystal Growth 79 (1986), p. 308-315). In this paper a ratio of crystal diameter (d) to a crucible diameter (D) has a magnitude d/D=0.4, which is an optimal value for Czochralski method. A condition of optimal dimensions of crucible for Czochralski method is a crucible height (H) is equaled to its diameter, D=H.
[0121] The low temperature gradients are a key peculiarity of large (80 mm-150 mm in diameter) crystals growing by a directional crystallization method, in particular Kyropoulos method from the iridium crucibles of 100 mm-180 mm in diameter, and an optimal ratio of a crystal diameter to a crucible diameter is d/D=0.7-0.9. Kyropoulos method is widely utilized for a commercial production of massive sapphire crystals (Al 2 O 3 ), and for some alkali-halide scintillation crystals also. However, the authors of given invention do not know publications about a growing of rare-earth silicates by Kyropoulos method. A technique and the attributes of Kyropoulos method and Czochralski method are described in detail in the book (K. T. Wilke “A growing of crystals” Leningrad, publisher <Nedra>, 1977, 600 p., a translation from German von K. Th. Wilke “Kristallzüchtungen”, VEB Deutcher Verlag der Wissenschaften, Berlin, 1973).
[0122] The drawings of scintillation substances growth corresponding to the variants #1, #2, #3 and #4 by Kyropoulos method are presented at FIG. 2 and FIG. 3 . A crystal growth is fulfilled from an iridium crucible 4 , a large in cross-section a lutetium oxyorthosilicate crystal is used as a seed crystal 5 , large cross-section dimension maintains a reliable start of crystal growth in the conditions of low temperature gradients and a strong light heating from an upper part of lateral crucible surface. At the beginning of crystal growth process a melt occupies only a part of crucible volume and H m is an optimal height of melt. At starting phase of crystal growth a cone 6 is growing and after shouldering a crystal 7 is being grown with a changeless diameter. A flow chart of crystal growth by Kyropoulos method for a case of 100% crystallized initial melt is shown on Fir. 2 . A flow chart of crystal growth for a case of partly (70%-90%) crystallized melt, when small amount of unused substance 9 is left in a crucible, is presented on FIG. 3 . The optimal values of a crucible diameter (D) and a height (H), an initial level of a melt in crucible (H m ), a crystal diameter (d) and length of cylindrical part of a crystal (h) are given by the relations:
h=H+y,
where y≈0.1 D; (d/D)≈0.7÷0.9; H m ≈(d/D) 2 h.
[0123] At the optimal ratio (d/D) 0.8 a grown crystal is placed within a crucible during cooling, that is an important condition for uniform decreasing of temperature over boule volume during an after-growth annealing. Such placement of a crystal relative to a crucible is a principal difference between Kyropoulos method and Czochralski method, in which a grown crystal is placed above the crucible after breaking away of melt to start an annealing process. A different position of crystal relative to crucible in Czochralski method results in the conditions under which a top of grown boule has an appreciably lower temperature than a bottom placed near a hot crucible. This circumstance leads to a different content of oxygen vacancies and to a different Ce 3+ /Ce 4+ ions ratio through the full crystal length, this is an additional cause of a strong spread of parameters from boule to boule grown by Czochralski method of the scintillating lutetium oxyorthosilicate crystals. All boules grown by Czochralski method have some differences of properties through the crystal length and its diameter, and in combination with annealing under the heavy temperature gradients this results in the considerable spread of parameters of scintillation elements fabricated from the different parts of boule. Contrariwise, the low temperatures gradients in a crystal during annealing process are achieved if a boule is placed within a crucible, as FIG. 2 and FIG. 3 demonstrates. Practically such method of fabrication allows to cool the crystals in the near isothermal conditions. This is a basis to achieve an invariability of light yield from the different parts of a large Kyropoulos grown crystal.
[0124] In the scintillation substance described in the variants #2, #4, #7 and #10 an isomorphic substitution of the lutetium ions for at least one of the ions of the group Gd, Sc, Y, La, Eu, Tb, is possibly, at that a substitution may be fulfilled at a more wide range than it is claimed in the given invention. However a conceptual drawback of considerable widening of a lutetium ions substitution range is a decrease of crystal density and, consequently, a sharp decrease of efficiency of gamma-quantums absorption that results in a decreasing of light yield. Besides, the Eu and Tb ions decrease the luminescence intensity in the blue region of spectrum because a part of energy due to the redistribution emits in a red region of spectrum at europium substitution and emits in a green region of spectrum at terbium substitution. In a case of the properly chosen concentrations of the cerium, terbium, and europium ions a scintillation crystal emits a white light, i.e. all visible region of spectrum. The scintillation substances having such emission spectrum more effectively work with the semiconductor detectors, because the cheap silicon/germanium semiconductor detectors have the two-tree times less sensitive in a blue region of spectrum in comparison with green, and moreover red region of spectrum. A substitution of Lu ions for the optically inactive Gd, Sc, Y, and La ions allows to control a lattice parameter and to grow the crystals free from a mechanical stresses reducing a crystal cracking during an after growth annealing and a cutting. Besides, a partial substitution of an expensive lutetium for the cheap La, Gd, and Y reduces a cost of scintillation substance.
[0125] The ion radiuses of Y (1.016 Å), La (1.190 Å), Eu (1.073 Å), Gd (1.061 Å), Tb (1.044 Å) are appreciably larger than the Lu (0.72 Å) ion radius. At interaction of gamma-quantum with a lattice a formation of the numerous quantity of free electrons and the holes, wherefrom these electrons were taken out by gamma-quantum, takes place. In consequent recombination of electrons with holes an excitation of lattice occurs, this energy transfers to the cerium ions which emit in blue range of spectrum. Specially a recombination is effective on the optical centers where the atoms having the very distinguishing radiuses are besides. For example, a substitution of part of lutetium ions for the lanthanum ions having significantly larger diameter results in a sharp light yield increasing, that will be proved in the examples of substances confirmatory the given invention. In order to an electron-hole recombination has a maximal effect the use of small concentrations of the isomorphic substituting dopants is required. At large concentrations a concentration quenching occurs and an efficiency is decreased, this lead to reducing of light yield. On the basis of the above reasoning and the experimental data, the range of variable z is chosen between 1×10 −4 f. units and 0.05 f. units for the variants of the substances Ce x Lu 2+2y−x−z A z Si 1−y O 5+y and Ce x Li q+p Lu 2−p+2y−x−z A z Si 1−y O 5+y−p , where A is at elements of the group Gd, Sc, Y, La, Eu, Tb. However, this range may be extended appreciably for the Y and La elements, for which an enlarged light yield is maintained even at the high concentrations while the crystal density is decreasing. Thus a technical result in the specific forms of implementations is achieved due to a growing of scintillation substance of Ce x Lu 2.076−x−m−n La m Y n Si 0.962 O 5.038 , in which the value of variable m does not exceed 0.05 f. units, and the range of variable n is between 1×10 −4 f. units and 2 f. units.
[0126] For the substances of the #6 and #10 variants having the chemical formulae Ce x Li q+p Lu 9.33−x−p−z □ 0.67 A z Si 6 O 26−p and Ce x Li 1+q+p Lu 9−x−p−z A z Si 6 O 26−p , accordingly, a range for variable z is set between 1×10 −4 f. units and 8.9 f. units. To maintain a large density and a high light yield the small concentrations are preferable as said the above. Nevertheless, an upper limit is set at 8.9 f. units, in this case the crystals have a low density and a comparatively small light yield with a sharp decreasing of an initial chemicals cost and, therefore, a crystal cost. Such crystals may be interest for utilization as the sensors in the atomic power plants for which the important parameters are a high radioresistance and chemical resistance in the compatibility with a low cost. The similar sensors should be in every room of plant to measure a radiation level without presence of human. The existent sensors on the basis of alkali-halide crystals are unreliable because they cannot operate in a high radiation level possible in case of the emergencies.
[0127] For the #3 and #4 variants of scintillation substance on the basis of lutetium silicate, a common distinctive feature is a presence of the lithium ions in the quantity does not exceeding 0.25 f. units, at that the lithium is placed in the interstitial sites of crystal lattice in the quantity of q formula units, another part of lithium ions are placed in the sites of the lattice substituting the lutetium ions in the quantity of p formula units. The positive effect of intercalation of the lithium ions into the interstitial sites of structure is achieved due to
[0000] (a) an intercalation is followed by the minimal change in a crystal structure of substance;
[0128] (b) an intercalation of the lithium ions gives rise to a formation of the reduced phases of Li q Ce, i.e. a presence of the lithium ions in the scintillation substances of Ce x Li q+p Lu 2−p+2y−x Si 1−y O 5+y−p and Ce x Li q+p Lu 2−p+2y−x−z A z Si 1−y O 5+y−p promotes to a stabilization of cerium ions in the Ce 3+ valence state, that appreciably increases a light yield;
[0000] (c) an intercalation of the lithium ions gives rise to the change of a conduction (A. A. Veshman, K. I. Petrov, “A functional inorganic lithium compounds” Moscow, Energoizdat, (1996), 208p.), that decreases an afterglow time of substance, TABLE 1.
[0129] For the #3 and #4 variants of substances, the lower p and q boundaries for a content of lithium are set to be equaled to 1×10 −4 f. units, because this is the limit of lithium content when the effect of a decreasing of afterglow and the effect of increasing of light yield are possibly to observe. The upper limit of the content of lithium in scintillation substance is determined by experimentally, at the total content of lithium ions exceeding 0.25 f. units a light yield intensity falls sharply due to a conduction of substance excessively rises and such scintillation substance becomes inapplicable to the industrial applications for its direct purpose—for the registration of x-ray, gamma and alpha radiation, TABLE 1.
[0130] All scintillation substances on the basis of silicate claimed in the #3 to #4 variants, inclusively, refer to a monoclinic syngony, a spatial group B2/b. The scintillation substances on the basis of silicate claimed in the fifth to tenth variants, inclusively, belong to another structural type, namely, apatite-brytolite with a spatial group P6 3 /m, Z=1. The substances claimed in the #6 #7 variants have an important common distinctive feature, namely, they contain the lithium ions of the total quantity (p+q) does not exceeding 0.55 f. units, where q denotes a quantity of lithium intercalated in the interstitial sites, p denotes a quantity of the lithium substituting the rare-earth ions. The upper limit of q equaled up to 0.3 f. units is determined by experimentally. When the quantity of lithium intercalated is above the indicated limit, the destruction of the structural type P6 3 /m and the formation of inclusions of other phases takes place, which determine the scattering of light and the decrease of transparency of a scintillating crystal. The upper limit of p equaled to 0.25 f. units is determined by the fact that an apatite-similar structure is retained at the substitution of the rare-earth atoms for lithium only for case, when a substitution of rare-earth atoms placed in the large nine-coordinated sites occurs, because only such sites let a distortion and a deviation from an ideal symmetry. With this the seven-coordinated sites, the second position for rare-earth ions in the structure, are always occupied by the rare-earth elements. The lower boundaries for the contents of lithium ions p and q are determined by the fact that at the quantity lower than the 5×10 −4 f. units limit a technical result, lying in increasing of the light yield and decreasing of the afterglow of scintillation, cannot be reached.
[0131] For the variants #9 and #10 the upper limit of the content of lithium is determined to 1.55 f. units, because apatite-brytolite structure remains a stable over a wide substitution range of elements of first position for the lithium ions. A substitution of large quantity of the basic-forming cerium ions for lutetium and cerium both in the mono-cation and double cerium silicates, being the analogues, lets to decrease the quenching effect of cerium luminescence and new substance obtains the scintillation properties.
[0132] Our experimental researches showed that the crystals of Ce x LiR 9−x Si 6 O 26 , and R 9.33 □ 0.67 Si 6 O 26 , where R═La, Gd, grown by Czochralski method have a high optical quality, however they are behind the lutetium oxyorthosilicate crystals both in a density and in a light yield. To improve the most important scintillation parameters we have grew the following crystals: Ce 0.015 LiGd 2.985 Lu 6 Si 6 O 26 ; Ce 0.015 LiLa 2.985 Lu 6 Si 6 O 26 ; Ce 0.015 LiGd 5.985 Lu 3 SiO 6 O 26 ; Ce 0.015 LiLu 8.985 Si 6 O 26 , Ce 0.015 Li 0.45 Lu 8.935 Si 6 O 26 , Ce 0.015 Li 0.12 Gd 2.985 Lu 6.33 □ 0.67 Si 6 O 26 , Ce 0.015 Li 0.33 Eu 1.985 Lu 6.3 □ 0.67 Si 6 O 26 , Ce 0.015 Li 0.25 Gd 2.985 Lu 6.28 □ 0.67 Si 6 O 26 , Ce 0.011 Li 0.25 Y 6.989 Lu 2.23 □ 0.67 Si 6 O 25.9 , Ce 0.011 Li 0.35 Y 3.989 La 0.9 Lu 3.33 □ 0.67 Si 6 O 25.9 , Ce 0.012 Li 0.05 La 3.988 Lu 5.33 □ 0.67 Si 6 O 26 . The numerous experiments with different growth conditions let to obtain this substances in the polycrystalline forms only. The testing of polycrystal of the Ce 0.015 LiLu 8.985 Si 6 O 26 composition shows that this new scintillation substance has near a density, a light yield and a decay time to the known Ce:LSO crystal.
[0133] To determine the boundaries of composition of scintillation substances of the variants #6 and #7 which possibly to grow in the form of single crystal we have tested the substances having an initial composition of melt: Ce 0.012 Li 0.1 Lu 5.33 La 3.988 □ 0.67 Si 6 O 26 ; Ce 0.012 Li 0.2 Lu 2.33 La 6.988 □ 0.67 Si 6 O 26 ; Ce 0.012 Li 0.1 Lu 5.33 La 3.988 □ 0.67 Si 6 O 26 ; Ce 0.015 Li 0.45 Lu 2.115 Gd 7 □ 0.67 Si 6 O 25.8 ; Ce 0.015 Li 0.1 Lu 7.31 Y 2 □ 0.67 Si 6 O 25.95 ; Ce 0.015 Li 0.28 Lu 7.815 Eu 1.5 □ 0.67 Si 6 O 2 . All these compositions were obtained in the forms of the single crystals, or the translucent, or the white nontransparent polycrystal ingots. For example, the use of a melt of the Ce 0.015 Li 0.55 Lu 1.065 La 8 □ 0.67 Si 6 O 25.75 chemical composition and at the 2.5 mm/hour pulling rate of growing crystal allows to grow from this melt the crystal of the Ce 0.003 Li 0.55 Lu 1.327 La 8 □ 0.67 Si 6 O 26 chemical composition. The increasing of pulling rate and gradients on the melt-crystal interface allows to obtain the new crystalline scintillation substances over the range of compositions from Ce 0.003 Li 0.55 Lu 1.077 La 8 □ 0.67 Si 6 O 25.75 to Ce 0.015 Li 0.55 Lu 1.065 La 8 □ 0.67 Si 6 O 25.75 . In a generalized form this new scintillation substance (the variants #6 and #7) has the following chemical formula: Ce x Li q+p Lu 9.33−x−p−z A z □ 0.67 Si 6 O 26−p , where the variables q and p does not exceed a value of 0.3 f. units and 0.25 f. units, respectively, a variable z is changed within the limits from 5×10 −4 f. units to 8.9 f. units.
[0134] To determine the boundaries of compositions of scintillation substances which possibly to grow in the form of a single crystal according to the #9 and #10 variants, the following substances of an initial composition of melt were tested: Ce 0.015 LiLu 8.985 Si 6 O 26 ; Ce 0.015 Li 1.55 Lu 8.735 Si 6 O 25.75 ; Ce 0.015 Li 1.05 Lu 8.985 Si 6 O 26 ; Ce 0.015 Li 1.3 Lu 1.785 La 7 Si 6 O 25.8 ; Ce 0.015 Li 1.4 Lu 6.885 Y 2 Si 6 O 25.9 ; Ce 0.015 Li 1.2 Lu 2.885 Gd 6 Si 6 O 25.9 . All these compositions were obtained in the form of single crystals or the translucent, or the white nontransparent polycrystal ingots. For example, the use of a melt of the Ce 0.015 LiLu 8.997 Si 6 O 26 chemical composition and at the 0.5 mm/hour pulling rate of growing crystal allows to grow from this melt the single crystal of the Ce 0.003 LiLu 8.997 Si 6 O 26 chemical composition. The increasing of pulling rate and gradients on the melt-crystal interface allows to obtain the new crystalline scintillation substances over the range of compositions from Ce 0.003 LiLu 8.997 Si 6 O 26 to Ce 0.015 Li 1.55 Lu 8.735 Si 6 O 25.75 . In a generalized form this new scintillation substance (the variants #9 and #10) has the following chemical formula: Ce x Li 1+q+p Lu 9−x−p A z Si 6 O 26−p , where the variables q and p does not exceed a value of 0.3 f. units and 0.25 f. units, respectively, a variable z is changed within the limits from 5×10 −4 f. units to 8.9 f. units.
[0135] We executed a sciagram analysis of the powdered Ce x Li q+p Lu 9−x−p Si 6 O 26−p crystal samples using X-ray diffractometer. The analysis showed that the Ce x Li q+p Lu 9−x−p Si 6 O 26−p single crystals being crystallized in a hexagonal syngony and may be classified to an apatite-brytolite structural type with a spatial group P6 3 /m, Z=1. The indexing X-ray diffraction pattern of the Ce 0.003 LiLu 8.997 Si 6 O 26 crystal is presented on FIG. 4 . Taking into account all 35 reflects from the planes at the 2θ angles of reflection over the range from 15 degrees to 60 degrees, we calculated the lattice cell parameters which are equaled to a=11.66 Å and c=21.58 Å.
[0136] The measurements of crystals density were carried out according to a standard procedure of hydrostatic weighing, this method is utilized in geology during ten-years. In these experiments we used the bulk polished samples weighing about 8-15 grams. The measurements were fulfilled in a distilled water preliminary boiled during 20 minutes to remove an oxygen and cooled to the room temperature. A temperature of water was being measured with an accuracy 0.1° C. To provide the minimal errors, each sample was weighed five times, in this case an error of determination of crystal samples density did not exceed 0.001 gram/cm 3 . The results of the measurements are presented in TABLE 1.
[0137] An experimental study of dependence of scintillation decay time and a light yield in the 410-450 nm range of spectrum on chemical composition of crystals was carried out utilizing an emission of radionuclide 60 Co as described in the article (E. G. Devitsin, V. A. Kozlov, S. Yu. Potashov, A. I. Zagumennyi, Yu. D. Zavartsev “Luminescent properties of Lu 3 Al 5 O 12 crystal doped with Ce” Proceeding of International Conferences “Inorganic scintillators and their applications” (SCINT 95), Delft, the Netherlands, Aug. 20-Sep. 01, 1995). The results of the measurements are presented in TABLE 1.
[0138] The measurements of a luminescence intensity and a time of an afterglow were fulfilled with the polished samples of 8-15 grams weight. The intensity and afterglow of reference sample were the same after the gamma-radiation and ultra-violet (UV) radiation exposures, so for the systematic measurements the UV-excitation set was used. A luminescence of the samples was excited by the standard 12 W UV-lamp during the 60 minutes exposure, after the switching-out of the lamp a fluorescence decreasing was recorded during 120 minutes with a photomultiplier FEU-100 or a photodetector FD-24K connected with oscilloscope Tektronix TDS 3052 or multimeter Agilent 34401A lined with computer. A variation of intensity of the samples having a strong afterglow effect are characterized by an exponential dependence having a time constant about 25-35 minutes, these samples maintain a strong fluorescence during more than the 180 minutes. The samples having a low afterglow effect are characterized by the dependence having a time constant about several decades seconds. For some samples an afterglow effect was not observed after switching-out of the lamp. The results of the afterglow effect measurements for the different samples are presented in TABLE 1.
BRIEF DESCRIPTION OF THE DRAWING
[0139] The essence of proposed technical solutions is illustrated by the following drawings:
[0140] FIG. 1 depicts the fragment of phase diagram of Lu 2 O 3 —SiO 2 system.
[0141] FIG. 2 shows the scheme of the optimal dimensions of a crystal and crucible for a case of crystal growth by Kyropoulos method.
[0142] FIG. 3 depicts a flow chart of crystal growth by Kyropoulos method for a case of partly crystallized melt.
[0143] FIG. 4 shows the X-ray powder diffraction pattern of Ce 0.003 Li 1.08 Lu 8.947 Si 6 O 25.95 crystal.
[0144] All crystals fabricated and examined during the fulfilment of the given invention were grown from the iridium crucibles, the chemicals with the extra-purity of 99.99% and 99.999% were used as the source reagents.
DETAILED DESCRIPTION OF THE INVENTION
[0145] TABLE 1 shows the results of testing of the synthesised scintillating substances. The values of the light yields, the decay times of scintillation, the afterglow times, the densities, the atomic numbers (Z eff ) are compared for different compounds. The values of light yield are presented in units relative to a light yield of “the reference” Ce 0.0024 Lu 1.998 SiO 5 sample (the Ce:LSO prototype crystal).
TABLE 1 Comparison of scintillating characteristics of the scintillation substances of different compositions. After Light glow Decay yield, presence Density Luminescence Atomic time (relative (relative (gram/ range number Compositions of substances (ns) units) units) cm 3 ) (nm) Z eff Ce 0.0024 Lu 1.998 SiO 5 43.3 1.0 1.0 7.406 415-430 63.8 Ce 0.001 Lu 2.075 Si 0.962 O 5.038 44.5 1.05 1.0 7.409 420-440 64.0 Ce 0.002 Lu 2.074 Si 0.962 O 5.038 43.4 1.0 0.8 7.408 420-440 64.0 Ce 0.0015 Lu 2.0445 Tb 0.03 Si 0.962 O 5.038 34.2 0.33 1.0 7.399 420-440 64.0 535-550 Ce 0.0015 Lu 2.0645 Tb 0.005 Eu 0.005 Si 0.962 O 5.04 34.7 0.32 1.05 7.406 420-440 64.0 535-550 620-635 Ce 0.0025 Lu 2.0685 Y 0.005 Si 0.962 O 5.038 42.7 1.09 0.9 7.403 425-445 64.0 Ce 0.0025 Lu 2.0685 Sc 0.005 Si 0.962 O 5.038 41 0.95 0.8 7.403 420-440 64.0 Ce 0.0025 Lu 2.0685 La 0.005 Si 0.962 O 5.038 43 1.12 0.8 7.404 430-450 64.0 Ce 0.0025 Lu 2.049 La 0.02 Si 0.962 O 5.038 44.1 1.27 0.9 7.394 430-450 63.9 Ce 0.003 Li 0.005 LU 2.049 La 0.02 Si 0.962 O 5.038 41.3 1.38 0.9 7.393 430-450 63.9 Ce 0.02 LiLu 8.98 Si 6 O 26 36 0.8 0.7 7.314 415-430 62.6 Ce 0.015 LiLu 6 Gd 2.985 Si 6 O 26 35.2 0.4 No 7.012 420-440 60.6 Ce 0.015 Li 0.45 Lu 8.935 Si 6 O 25.65 36 0.9 0.2 7.331 415-430 62.6 Ce 0.015 LiLu 6 La 2.985 Si 6 O 26 38 1.4 0.3 6.701 420-440 59.1 Ce 0.003 LiLu 8.997 Si 6 O 26 39.7 1.2 0.3 7.318 415-430 62.6 Ce 0.003 Li 1.08 Lu 8.947 Si 6 O 25.97 39 1.2 0.3 7.310 415-430 62.6 Ce 0.015 Li 1.55 Lu 8.735 Si 6 O 25.9 35 0.75 0.2 7.270 415-430 62.6 Ce 0.015 LiLu 3 Gd 5.985 Si 6 O 26 31 0.3 No 6.691 430-440 58.3 Ce 0.001 Li 1.2 Lu 3.698 Gd 5.1 Si 6 O 26.1 34 0.35 No 6.784 430-440 59.0 Ce 0.04 Li 1.2 Lu 8.66 Eu 0.2 Si 6 O 25.95 33 0.25 0.2 7.285 420-440 62.3 620-635 Ce 0.1 Li 1.2 Lu 7.9 Y 0.7 Tb 0.1 Si 6 O 25.8 28 0.35 0.2 7.095 420-440 61.3 535-550 Ce 0.002 Li 1.45 Lu 6.298 Y 2.5 Si 6 O 25.93 42 1.1 0.5 6.645 425-445 58.3 Ce 0.0015 Li 1.3 Lu 8.3985 La 0.5 Si 6 O 26 42 1.2 0.5 7.198 430-450 62.0 Ce 0.015 Li 0.1 Lu 6.33 Gd 2.985 □ 0.67 Si 6 O 26.06 32 0.4 No 7.083 430-440 61.0 Ce 0.015 Li 0.33 Lu 7.3 Eu 1.985 □ 0.67 Si 6 O 26.1 34.5 0.09 No 7.019 420-440 61.4 620-635 Ce 0.015 Li 0.25 Lu 6.28 Gd 2.985 □ 0.67 Si 6 O 26.05 36 0.5 No 7.073 430-440 60.9 Ce 0.011 Li 0.2 Lu 2.23 Y 6.989 □ 0.67 Si 6 O 25.95 41 1.0 0.7 5.261 425-445 46.6 Ce 0.011 Li 0.1 Lu 3.33 Y 5.989 □ 0.67 Si 6 O 26 44 1.4 1.0 5.749 425-445 51.0 Ce 0.012 Li 0.05 Lu 5.33 La 3.988 □ 0.67 Si 6 O 26 44 1.2 1.0 6.570 430-450 58.3 Ce 0.003 Li 0.55 Lu 1.077 La 8 □ 0.67 Si 6 O 25.9 41 0.8 No 5.549 430-450 51.4
EXAMPLE 1
[0146] Growth of known a “reference” Ce:Lu 2 SiO 5 crystal having the Lu/Si=2 ratio, and also the growing of crystal having a ratio of formula units of (Lu+Ce)/Si=2.061 (y=0.015), which is out of compositions range of variant No. 1 of given invention.
[0147] Due to a strong data spread about the crystal parameters published in the different issues, the parameters of commercial Ce:Lu 2 SiO 5 crystals may be accepted as the most reliable data. The higher light output is demonstrated by the LSO crystals, having a concentration of cerium ions equaled to 0.12 at. % (or about 0.002 f. units), the chemical formula of reference crystal is Ce 0.002 Lu 1.998 SiO 5 . Taking into account that the segregation coefficient of the cerium ions between a melt and growing crystal is equaled about k=0.2, it is needed to charge a crucible with the starting material having a cerium concentration about 0.6 at. % (or in the formula units: 0.012 f. units). A ratio of the Lu 2 O 3 and SiO 2 oxides should be calculated taking into account the peculiarities of a directional crystallization method (Czochralski method, Stepanov's method, the Bridgman method or any other method of a directional crystallization). We have grew the “reference” Ce:Lu 2 SiO 5 crystals by Czochralski method in the conditions of low temperature gradients (Experiment #1) and in conditions of high temperature gradients (Experiment #2 and #3).
[0148] Experiment #1. (The non-equilibrium conditions, charge composition of 50% (Lu 2 O 3 +Ce 2 O 3 )/50% SiO 2 ). A growing of crystal was carried out from an iridium crucible of the 40 mm in diameter under a weak thermal insulation in protective argon atmosphere (100% volume of argon), at pulling rate of 3.5 mm h −1 , rotation rate of 15 r.p.m. The initial charge of a melt had a composition described by a chemical formula of Ce 0.012 Lu 1.998 SiO 5 . In these conditions a crystal approximately 16 mm in diameter and 54 mm length was grown, a top of boule was colourless and did not have the fine scattering inclusions, but a bottom of boule had the cracks. The content of cerium, lutetium and silicon ions was determined in crystal by electron microprobe analysis using the commercial Cameca Camebax SX-50 spectrometer. A composition of top conical part of the crystal is characterised by the chemical formula of Ce 0.002 Lu 1.998 SiO 5 , having ratio of (Lu+Ce)/Si equaled exactly to 2, that is possible in the conditions of crystallisation far from the equilibrium. However in the bottom of crystal the ratio of (Lu+Ce)/Si becomes less than 2. For fabrication of “reference” sample the top of conical part of the boule was used. The parameters of “reference” sample are presented in TABLE 1.
[0149] Experiment #2. (The equilibrium conditions, charge composition of 50% (Lu 2 O 3 +Ce 2 O 3 )/50% SiO 2 ). A growing of crystal was executed from an iridium crucible of the 40 mm in diameter under a good thermal insulation conditions in a protective argon atmosphere (99.5% volume of argon and 0.5% volume of oxygen), at pulling rate of 2 mm h −1 , rotation rate of 15 r.p.m. The initial charge of a melt had a composition described by a chemical formula of Ce 0.012 Lu 1.998 SiO 5 . In these growth conditions the crystal approximately 18 mm in diameter and 45 mm length was grown, the crystal did not contain the fine scattering inclusions and was a colourless. The content of cerium, lutetium and silicon ions was determined in crystal by electron microprobe analysis using the commercial spectrometer. A composition of top conical part of the crystal is characterised by the chemical formula of Ce 0.003 Lu 2.027 Si 0.985 O 5.015 , having ratio of (Lu+Ce)/Si=2.061. To the bottom of crystal the concentration of cerium ions is being increased, and ratio of (Lu+Ce)/Si becomes a lower than 2.061. Obviously, that such crystal cannot be used as a “reference” sample, because its composition is differed from composition of known Lu 2−x Ce x SiO 5 crystal.
[0150] Experiment #3. (Charge composition is 46% (Lu 2 O 3 +Ce 2 O 3 )/54% SiO 2 ). A growing of crystal was executed from an iridium crucible of the 40 mm in diameter under a good thermal insulation in a protective atmosphere (99.5% volume of argon and 0.5% volume of oxygen), at pulling rate of 2 mm h −1 , rotation rate of 15 round per minutes (r.p.m). In accordance with a composition is denoted by an arrow 2 of FIG. 1 it is needed to use the original charge composition of 46% (Lu 2 O 3 +Ce 2 O 3 )/54% SiO 2 , which corresponds to a melt having the Ce 0.012 Lu 1.828 Si 1.080 O 4.920 chemical composition. In these conditions the crystal 52 mm in length and 16 mm diameter was grown. The crystal was colourless, but it included the fine scattering inclusions, an amount of which was increased from a top to a bottom of a boule. The content of cerium, lutetium and silicon ions was determined in a top part of crystal by electron microprobe analysis using the commercial spectrometer. A composition of the crystal is within the compositions range between the Ce 0.0022 Lu 1.997 Si 1.0 O 5 (a top part of a boule) and the Ce 0.0028 Lu 1.968 Si 1.010 O 4.98 (a bottom part of boule).
[0151] A comparison of scintillation parameters of couple of samples, fabricated in the experiments #3 and #3, had shown, that they have approximately identical light output under gamma excitation, and both samples demonstrated approximately the same decay time τ=43 ns.
EXAMPLE 2
[0152] A confirmation of the invention in the particular forms of implementation—the method of making of scintillation substances. To grow a large single crystal by Kyropoulos method according with the variants #1, #2, #3, and #4, an optimal scintillation substance having a composition of charge characterised by an oxides mole ratio of 51.9% (Ce 2 O 3 +Lu 2 O 3 +A 2 O 3 +Li 2 O)/48.1% SiO 2 was chose. At such oxides ratio, the compositions of a melt and of a crystal are characterised by a chemical formula of Ce x Li q+p Lu 2.076−p−x−z A z Si 0.962 O 5.038−p , where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb, x is a value between 1×10 −4 f. units and 0.02 f. units, z is a value not exceeding 0.05 f. units, q+p is a value not exceeding 0.025 f. units.
[0153] The growing of crystal 78 mm in diameter was executed from iridium crucible of 96 mm in inner diameter and about 112 mm height using the computer-controlled installation equipped with a weighing system of growing crystal. Placed in an optimal thermal insulation crucible was filled with the mixed chemical reagents, a crystal growing was carried out in a flowing protective nitrogen atmosphere (99.7% volume of nitrogen with 0.3% volume of oxygen). A weight of starting charge of crucible was 4400 grams. An initial charge had a chemical composition Ce x Lu 2.076−x Si 0.962 O 5.038 , characterised by the oxides mole ratio of 51.9% (Lu 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 . The single crystal rod of 12×12 mm 2 section was used crystal. The pulling rate of crystal boule was being changed from 1 mm/hr to 8 mm/hr at the different stages of process. The shouldering of crystal from the seed size until diameter size of approximately 75-78 mm was accomplished along crystal length from 5 mm to 25 mm, after that the boule was grown at constant cylindrical diameter of 75-78 mm. The finishing of growth was carried out by means of increasing of pulling rate when the boule weight achieved the desired value of about 90% of charge (the crystallized melt fraction is 90%). The moment of breaking off of a crystal from a melt was fixed by the weighing system. An annealing and a cooling of crystal to room temperature was being carried out during 30 hours. Grown at these conditions crystal had 3910 grams in a weight of and 12.5 cm length. Due to such technology, the effect of crucible bloat is eliminated. The enlarge/distension of iridium crucible during cooling of melt occurred if the amount of residual melt is occupied more than 20% of crucible volume. The enlarge and bloat of crucible sharply decreases a life time of very expensive iridium crucible, and, therefore, the production cost of a crystal boule is being increased.
[0154] An obtained crystal boule was used for measurement of percentage loss of crystalline materials after a slicing, a sawing of boule into the thin elements, a screening and rejection of debris, the broken elements and elements having the small cracks. The second kind of losses depend on a thickness of diamond saws, however these losses easy to calculate taking into account a thickness of a saw, so they do not considering in given example.
[0155] The sawing of boule at the packs of 78 mm in diameter and 11 mm length was fulfilled by the diamond saw with the inner cutting edge having the thickness of 0.6 mm. After this stage was obtained the 9 slabs, which had not the cracks and spalls. At this stage of fabrication the losses was 0%. During the second stage the packs were cut in perpendicular direction into the plats of 1 mm thickness, a diamond saw with inner cutting edge of 0.2 mm thickness was used. In a result of cracks the losses were ˜1%. In next stage the plats were glued together and cut into the rods with size of 1×1×11 mm 3 . In result of cracks the losses achieved ˜3%. In the final stage the rods were glued into the blocks containing approximately 30×30 rods in each, the blocks were mechanically polished from one or both faces of scintillating elements. During this processing the losses were no more than 0.1%. Thus, in a result of cracks the total losses achieved about 4%.
[0156] For comparison the known Ce:Lu 2 SiO 5 crystal 50 mm in diameter and 105 mm length was grown by Czochralski method using a crucible 100 mm in diameter and 100 mm height, the crystal was grown from a melt of initial composition characterised by chemical formula Ce 0.012 Lu 1.998 SiO 5 . After the cutting of boule at the packs 50 mm in diameter and 11 mm length the cracks were observed in volume of 3 slabs from total 8 slabs. During fabrication of rods with size 1×1×11 mm 3 having one mechanically polished face the losses of crystalline material in a result of cracks and spalls achieved totally about 32%.
[0157] The same technological scheme was used for a growing and a cutting of the crystals having compositions: Ce x Li 0.08 Lu 2.026−x Si 0.962 O 5.008−p , Ce x Li 0.02 Lu 2.072−x Si 0.962 O 5.034 , Ce x Lu 2.066−x−z La 0.01 Si 0.962 O 5.038 , Ce x Lu 2.036−x Y 0.04 Si 0.962 O 5.038 , Ce x Li 0.2 Lu 2.006−x Gd 0.04 Si 0.962 O 5.018 , Ce x Li 0.15 Lu 2.071−x−z Tb z Si 0.962 O 4.988 , with a different content of cerium, x is a value between 1×10 −4 f. units and 0.02 f. units.
[0158] The chemical compositions of the melts offered in the given invention and a growing of crystals by Kyropoulas method allow sharply to reduce the losses of crystalline scintillation material in the stages of cutting of large boules.
EXAMPLE 3
[0159] Method of making of the scintillation substances in form of scintillating ceramics on the basis of lanthanum and lutetium oxyorthosilicate differed in that the mixture of chloride water solution of Lu, La, Ce and liquid of SiCl 4 , are used as a starting material for preparation of charge of composition characterised by the oxides mole ratio of 51.9% (Lu 2 O 3 +La 2 O 3 +Ce 2 O 3 )/48.1% SiO 2 . An ammonium carbonate water solution was added to the said mixture. Then this mixture was filtering, drain and drying. After calcination at 1400° C. the obtained oxides mixture stirred with addition of solvent and low-melting impurities, which promote an atoms diffusion through boundary of grains during a final high temperature annealing. The numerous compounds may be used as the low-melting impurities, which do not influence on an emission of Ce 3+ ions. Our investigations showed that the small additives of Li, Na, K, Cs, Be, B, F, Al, S, Cl, Zn, Sc, Ga, Ge, Se, Br, I, Sn, and In ions do not lead to decrease of light output of scintillating ceramics. A sintering aid of Mg, P, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, As, Sr, Zr, Nb, Mo, Cd, Sb, Ba, Hf, Ta, W, Pb, Bi ions decreases or completely suppresses of Ce 3+ ions emission. The sintering aid of lithium compounds, for example, LiCl, Li 2 GeF 6 , Li 2 GeO 3 , Li 3 BO 3 promote for production of good optical quality scintillation ceramics. After removal of the trace of water and organic components, two ways of synthesis of ceramic are possible.
[0160] A first method. The oxide materials with the additives of Li 2 GeO 3 , Li 3 BO 3 was charged into a soft platinum capsule, then the capsule was pumped in a vacuum and the hole was solder using a gas-jet. After ceramic was being synthesising in the capsule, which was placed under a massive press-form at temperature 1300° C. under 1000 atm. pressure during 2 hours.
[0161] A second method. The oxide materials with the additives of Li 2 GeO 3 , Li 3 BO 3 was pressed under 2000 atm pressure. After that during the few hours the pressed pellets (of square or other shape) were annealed in a vacuum at temperature about 1700-1840° C. To eliminate the violet colour centers and to improve an optical quality, the pellets were annealed during 24 hours on air at temperature about 1300° C. at the final stage. In a result of these actions the scintillation ceramic products covered by thin white coat at all sides were obtained. Produced by this technique elements may be used for the X-ray computer tomography systems.
EXAMPLE 4
[0162] A scintillation substance based on a silicate comprising a lutetium (Lu) and cerium (Ce) characterised in that the composition of the substance in the form of a single crystal is represented by the chemical formula Ce x Lu 2+2y−x−z A z Si 1−y O 5+y , where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb, Ca, x is a value between 1×10 −4 f.u. and 0.02 f.u., y is a value between 0.024 f.u. and 0.09 f.u., z is a value between 1×10 −4 f.u. and 0.05 f.u.
[0163] The oxide chemicals (Lu 2 O 3 , Tb 2 O 3 , CeO 2 , SiO 2 ) with purity of 99.995% were used for the growing by Czochralski method of lutetium-terbium-cerium orthosilicate of the composition of Ce 0.002 Lu 2.044 Tb 0.03 Si 0.962 O 5.038 . The crystal growth was executed from an iridium crucible of the 54 mm in diameter and 54 mm height containing the melt characterised by a mole ratio of oxides 51.9% (Ce 2 O 3 +Lu 2 O 3 +Tb 2 O 3 )/48.1% SiO 2 . The pulling rate was 2 mm/hour, rotation rate of 15 r.p.m. Crystallization was executed in a protective argon atmosphere (99.5% volume of argon with 0.5% volume of oxygen). The crystal of 55 mm length and 26 mm in diameter had a high optical quality and did not comprise the fine scattering inclusions. The polished samples from this crystal were used for the measurement of parameters are presented in TABLE 1.
[0164] The growing by Czochralski technique of lutetium-lanthanum-cerium orthosilicate of the composition of Lu 2.1 La 0.02 Ce 0.0015 Si 0.94 O 5.06 was executed from the iridium crucible of the 38 mm in diameter and 38 mm height containing the melt characterised by the oxides mole ratio of 51.9% (Ce 2 O 3 +Lu 2 O 3 +La 2 O 3 )/48.1% SiO 2 . The pulling rate was 3 mm/hour, rotation rate of 10 r.p.m. Crystallization was executed in protective argon atmosphere (99.5% volume of argon with 0.5% volume of oxygen). The crystal 17 mm in diameter and 20 mm length had the high optical quality and did not comprise the fine scattering inclusions. The polished samples from this crystal were used for measurement of parameters presented in TABLE 1. The analogous growth conditions were used for production of many samples, which parameters are presented in TABLE 1.
EXAMPLE 5
[0165] A confirmation of the invention in the particular forms of implementation for variants #2 of given invention is the scintillation substances in the form of a single crystal having the chemical formula of Ce x Lu 2.076−x−m−n La m Y n Si 0.962 O 5.038 , where x is a value between 1×10 −4 f.u. and 0.02 f.u., m is a value does not exceeding 0.05 f.u., n is a value between 1×10 −4 f.u. and 2.0 f.u.
[0166] The growing by Czochralski technique of lutetium-yttrium-lantanium-cerium orthosilicate of the chemical composition of Ce 0.002 Lu 1.324 Y 0.7 La 0.05 Si 0.962 O 5.038 was executed from the iridium crucible of the 38 mm in diameter and 38 mm height, the pulling rate was 3 mm/hour and rotation rate of 15 r.p.m. Crystallization executed from the melt characterised by the mole ratio of oxides 51.9% (Lu 2 O 3 +Y 2 O 3 +Ce 2 O 3 +La 2 O 3 )/48.1% SiO 2 in protective argon atmosphere (99.5% volume of argon with 0.5% volume of oxygen). The crystal 16 mm in diameter and 60 mm length was colourless and did not have the cracks during growth process, however the cracks appeared in the middle part of crystal boule during 24 hours cooling stage. The top of crystal did not contain the fine scattering inclusions, but the numerous scattering inclusions were in the bottom of boule. Under gamma excitation the sample from the top of crystal have demonstrated the light output about 1.3 times higher than light output of a “reference” Ce:Lu 2 SiO 5 crystal described in EXAMPLE 1.
EXAMPLE 6
[0167] A scintillation substance containing a lithium (Li) ions, according to variants #3 and #4 of given invention, having the composition represented by the chemical formula of Ce x Li q+p Lu 2−p+2y−x−z A z Si 1−y O 5+y−p , where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb, x is a value between 1×10 −4 f. units and 0.02 f. units, y is a value between 0.024 f. units and 0.09 f. units, q is a value between 1×10 −4 f. units and 0.2 f. units, p is a value between 1×10 −4 f. units and 0.05 f. units, z is a value does not exceeding 0.05 f. units.
[0168] To obtain the Ce 0.003 Li 0.005 Lu 2.049 La 0.02 Si 0.962 O 5.038 crystal, the following method of making of the samples was used: the initial chemicals of lutetium oxide, silicon oxide and lithium carbonate in the quantities determined by mole relationship of oxides 51.9% (Lu 2 O 3 +Li 2 O+Ce 2 O 3 +A 2 O 3 )/48.1% SiO 2 were thoroughly mixed, pressed in pellets and synthesised in a platinum crucible during 10 hours at 1250° C. Then by means of induction heating the pellets were melted in an iridium crucible in a hermetically sealed chamber in protective nitrogen atmosphere (99.7% volume of nitrogen with 0.3% volume of oxygen). A cerium oxide was added into the melt before a crystal growth. The crystal 60 mm in diameter and cylindrical part of 45 mm length was grown by Kyropoulas method from the iridium crucible of the 76 mm in diameter and 78 mm height. The volume of the initial melt was equaled to 290 cm 3 . The pull rate of crystal boule was varied from 1 mm/hr to 8 mm/hr at the different stages of growth, the rotation rate was 10 r.p.m. When the boule has grown, it was breaking off from the melt and cooled during 30 hours till room temperature. The polished samples from this boule were used for the measurements of parameters presented in TABLE 1.
[0169] The growing by Czochralski technique of the scintillation substance on the basis a lutetium-cerium orthosilicate, containing a lithium, having the chemical composition of Ce x Li 0.08 Lu 2.026−x Si 0.962 O 5.008−p was executed from iridium crucible of the 36 mm in diameter and 38 mm height with the pulling rate 2.7 mm/hour and rotation rate of 14 r.p.m. Crystallization was executed from the melt of composition determined by the mole ratio of oxides 51.9% (Lu 2 O 3 +Ce 2 O 3 +Li 2 O)/48.1% Si 2 in a protective argon atmosphere (99.7% volume of argon with 0.3% volume of oxygen). The crystal 19 mm in diameter and 60 mm length was colourless and did not have a cracking during growth process and in a stage of 22 hours cooling. As the top so the bottom of crystal did not contain the fine scattering inclusions except of the peripheral part of volume of the thickness about 0.5-0.7 mm. Under gamma excitation the sample from the top part of crystal demonstrated about the same value of light output as light output of a “reference” Ce:Lu 2 SiO 5 crystal described in EXAMPLE 1. The same technological scheme was used for a growing and a cutting of the crystals having compositions: Ce x Li 0.02 Lu 2.072−x Si 0. 962 O 5.034 , Ce x Lu 2.036−x Y 0.04 Si 0.962 O 5.038 , Ce x Li 0.2 Lu 2.006−x Gd 0.04 Si 0.962 O 5.018 , Ce x Li 0.15 Lu 2.071−x−z Tb z Si 0.962 O 4.988 , with a different content of cerium, x is a value between 1×10 −4 f. units and 0.02 f. units.
EXAMPLE 7
[0170] A scintillation substance according to variants #5 on the basis of a lutetium-cerium silicate containing the cation vacancies and having the composition represented by the chemical formula Ce x Lu 9.33−x □ 0.67 Si 6 O 26 where x is a value between 1×10 ∝ f. units and 0.1 f. units.
[0171] The growing by Czochralski technique of the scintillation substance on the basis of a mono-cation lutetium-cerium silicate having the chemical composition of Ce 0.002 Lu 9.328 □ 0.67 Si 6 O 26 , executed from an iridium crucible of the inner diameter of 37 mm and 40 mm in height with the pulling rate of 2.7 mm/hour and rotation rate of 14 r.p.m. Crystallization was executed from the melt of stoichiometric composition in protective argon atmosphere (99.7% volume of argon with 0.3% volume of oxygen). The crystal 22 mm in diameter and 58 mm length was colourless and did not had a cracking during growth process and in a stage of 12 hours cooling. The bulk volume of crystal contained some fine scattering inclusions, the density of inclusions was increased to the bottom part of boule. The scintillation samples were made in according with technology described in EXAMPLE 1.
[0172] The same technological scheme was used for a growing and a cutting of the crystals having compositions: Ce 0.04 Lu 9.29 □ 0.67 Si 6 O 26 , Ce 0.1 Lu 9.23 □ 0.67 Si 6 O 26 . It is necessary to note that the increasing of cerium ions concentration reduced a quantity of scattering inclusions.
EXAMPLE 8
[0173] A scintillation substance according to variants #5 on the basis of a lutetium-cerium silicate containing lithium and the cation vacancies and having the composition represented by the chemical formula Ce x Li q+p Lu 9.33−x−p □ 0.67 Si 6 O 26−p , where x is a value between 1×10 −4 f. units and 0.1 f. units, q is a value between 1×10 −4 f. units and 0.3 f. units, p is a value between 1×10 −4 f. units and 0.25 f. units.
[0174] The growth by Czochralski technique of the scintillation substance on the basis of a mono-cation lutetium-cerium silicate containing lithium and cation vacancies and having the composition represented by the chemical formula of Ce x Li q+p Lu 9.33−x−p □ 0.67 Si 6 O 26−p , was executed from the iridium crucible of the 37 mm in diameter and 40 mm height with the pulling rate 2.7 mm/hour and rotation rate of 12 r.p.m. Crystallization was executed from the melt of stoichiometric composition in protective nitrogen atmosphere (99.7% volume of nitrogen with 0.3% volume of oxygen). The crystal 22 mm in diameter and 52 mm length was colourless and did not have a cracking during a growing and in a stage of 12 hours cooling. The bulk volume of crystal contained some amount of fine scattering inclusions. The scintillation samples were made in according with technology described in EXAMPLE 1.
[0175] The same technological scheme was used for a growing and a cutting of the crystals having the compositions: Ce 0.001 Li 0.12 Lu 9.279 □ 0.67 Si 6 O 25.95 , Ce 0.05 Li 0.4 Lu 9.08 □ 0.67 Si 6 ) 25.8 .
EXAMPLE 9
[0176] A scintillation substance according to variants #7 on the basis of a lutetium-cerium silicate containing lithium and cation vacancies and having the composition represented by the chemical formula Ce x Li q+p Lu 9.33−x−p−z □ 0.67 A z Si 6 O 26−p , where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb, x is a value between 1×10 −4 f. units and 0.1 f. units, q is a value between 1×10 −4 f. units and 0.3 f. units, p is a value between 1×10 −4 f. units and 0.25 f. units, z is a value between 5×10 −4 f. units and 8.9 f. units.
[0177] A growing by Czochralski technique of the scintillation substance on the basis of a mono-cation lutetium-cerium silicate containing lithium and cation vacancies and having the composition represented by the chemical formula Ce 0.002 Li 0.2 Lu 7.228−p □ 0.67 La 2 Si 6 O 25.9 was executed from iridium crucible of the 37 mm in diameter and 40 mm height with the pulling rate of 2.7 mm/hour and rotation rate of 12 r.p.m. Crystallization was executed from the melt of stoichiometric composition in protective nitrogen atmosphere (99.8% volume of nitrogen with 0.2% volume of oxygen). The crystal 22 mm in diameter and 52 mm length was colourless and did not have a cracking during growth and in stage of 12 hours cooling. The bulk volume of crystal contained some fine scattering inclusions. The scintillation samples were made in according with technology described in EXAMPLE 1.
[0178] The same technological scheme was used for a growing and a cutting of the crystals having the compositions: Ce 0.002 Li 0.2 Lu 1.228−p □ 0.67 Y 8 Si 6 O 25.9 , Ce 0.001 Li 0.1 Lu 8.324 □ 0.67 YSi 6 O 25.995 , Ce 0.001 Li 0.15 Lu 4.279 □ 0.67 Gd 5 Si 6 O 25.95 , Ce 0.001 Li 0.35 Lu 9.109 □ 0.67 Tb 0.2 Si 6 O 25.8 , Ce 0.002 Li 0.1 Lu 0.423 □ 0.67 La 8.9 Si 6 O 25.95 .
EXAMPLE 10
[0179] A scintillation substance according to the variants #8 and #9 on the basis of lutetium-cerium silicate containing a lithium (Li) in the quantity not a less than 1.0 f. units and having the composition represented by the chemical formula Ce x Li 1+q+p Lu 9−g−x−p Si 6 O 26−p , where x is a value between 1×10 −4 f. units and 0.1 f. units, q is a value in the quantity does not exceeding 0.3 f. units, p is a value in the quantity does not exceeding 0.25 f. units.
[0180] An important distinguishing technical indication of given scintillation substances is their melting point, which is a little higher than 1700° C., that is more than 300° lower than for crystals crystallised in a structural type of lutetium oxyorthosilicate. The low temperature of melting is the essential advantage for a crystal growth by Czochralski technique, because in this case the time of iridium crucibles operation is increased in tens time. There is more important a long time of usage, if the crystals growth is being carried out by Stepanov's method. An utilization of Stepanov's method opens a possibility to grow the several scintillating crystals simultaneously, for example, with size 2×2×100 mm 3 or the size 1×1×50 mm 3 . It allows to eliminated the expensive stage of a cutting of a large boule into thin rods. During a cutting possibly to lost of 20%-50% of single crystal material, that considerably increases the manufacturing cost of scintillating elements for medical Micro-Positron-Emission computer Tomography (MicroPET).
[0181] In the process of growth of a profiled crystal from a melt, the crystal cross-section is determined by the form of melt column. Different physical effects are used for the shaping of a melt. A formation of a square cross-section melt column is carried out by means of an iridium former. A design of the formers and methodology of calculation of the optimal growth conditions are described in the book (P. I. Antonov, L. M. Zatulovski, A. S. Kostygov and others “An obtaining of profiled single crystals and products by Stepanov's method”, L., “Nauka”, 1981, p. 280.).
[0182] A growing of a profiled crystal by Stepanov's method was executed from an iridium crucible equipped with the iridium former, having an outer edge cross-section of 2×2 mm 2 , which determined the cross-section of a pulling crystal. To obtain the Ce 0.045 Li 1.300 Lu 8.905 Si 6 O 25.995 crystal crystallising in a hexagonal structural type, the charge of stoichiometric composition having the chemical formula Ce 0.045 Li 1.300 Lu 8.905 Si 6 O 25.995 was used. The following method was used for the burden preparation. The source reagents of a lithium carbonate, lutetium oxide and silicon oxide were thoroughly mixed and partially synthesised in a platinum crucible during 10 hours at 1300° C. Then, by means of induction heating the powder was melted in an iridium crucible in flow protective nitrogen atmosphere (99.7% volume of nitrogen with 0.3% volume of oxygen). A cerium oxide was added into the melt before a crystal growth. The former allowed to grow from one to nine profiled crystals simultaneously. Seeding was fulfilled onto the crystal obtained by Czochralski technique. A seed crystal was cut along a crystallographic direction of the axis of six order. The profiled crystals were pulled out of melt at a speed of 3-20 mm/hour without rotation. Upon the crystal reaching the length of 50 mm they were broken away from the former by a sharp increasing of the pulling speed and 30 minutes later they were being extracted from installation.
[0183] The profiled crystal rods were cut into the few scintillating elements with sizes 2×2×10 mm 3 . The polished samples of Ce 0.045 Li 1.300 Lu 8.905 Si 6 O 25.995 crystal were used for measurements of parameters presented in TABLE 1.
[0184] The same technological scheme was used for a growing and a cutting of the crystals having the compositions: Ce 0.001 LiLu 8.998 Si 6 O 26 , Ce 0.04 LiLu 8.96 Si 6 O 26 , Ce 0.1 LiLu 8.9 Si 6 O 26 , Ce 0.002 Li 1.45 Lu 8.798−p Si 6 O 25.8 , Ce 0.0015 Li 1.3 Lu 8.8985−p Si 6 O 25.9 .
EXAMPLE 11
[0185] A scintillation substance according to variant #10 on the basis of silicate containing a lutetium (Lu) and cerium (Ce) and characterised in that it contains a lithium Li in the quantity exceeding 1.0 f.u. and its composition is represented by the chemical formula Ce x Li 1+q+p Lu 9−x−p−z A z Si 6 O 26−p , where A is at least one element selected from the group consisting of Gd, Sc, Y, La, Eu, Tb, x is a value between 1×10 −4 f. units and 0.1 f. units, q is a value between 1×10 −4 f. units and 0.3 f. units, p is a value between 1×10 −4 f. units and 0.25 f. units, z is a value between 5×10 −4 f.u. and 8.9 f. units.
[0186] To obtain a scintillation substance of composition of Ce 0.045 Li 1.1 Lu 0.08 La 0.02 Y 8.755 Si 6 O 26 crystallising in a hexagonal syngony, the charge of stoichiometric composition having the chemical formula of Ce 0.045 Li 1.1 Lu 0.08 La 0.02 Gd 8.755 Si 6 O 26 was used. A growing of crystal was executed from an iridium crucible of the 40 mm in diameter in a protective atmosphere (99.5% volume of nitrogen with 0.5% volume of oxygen), the pulling rates were 5 mm/hour and 10 mm/hour and rotation rate was 11 r.p.m. In these growth conditions the crystal approximately 35 mm length and 18 mm in diameter was grown, the boule had a white-yellow colour and did not have the fine scattering inclusions even at the 10 mm/hour pulling rate. The polished sample of this crystal under gamma excitation demonstrated the light output about 10 time lower than a light output of a “reference” Ce:Lu 2 SiO 5 crystal, a technology of fabrication of which is described in EXAMPLE 1. On the basis of this an upper limit of substitution of lutetium ions by other elements in the substances of variant #10 having the chemical formula of Ce x Li 1+q+p Lu 9−x−p−z A z Si 6 O 26−p was set at the value of z=8.9 f. units. In this case the crystals have a significantly lower density and light output, however the cost of charged reagents, and, therefore, a manufacturing cost of scintillation crystals are being decreased appreciably. Such crystals are being interested for utilization in the sensors, for which the more important parameter is a low price and a high resistance of scintillator to the outside exposure, such as a high temperature, a big humidity, a very high level of radiation, which may destroy, for example, a gamma dosimeter.
[0187] The same technological scheme was used for a growing of crystals having the compositions: Ce 0.001 Li 1.2 Lu 3.898 Gd 5.1 Si 6 O 26 , Ce 0.04 Li 1.2 Lu 8.66 Eu 0.2 Si 6 O 25.9 , Ce 0.1 Li 1.2 Lu 7.9 Sc 0.8 Si 6 O 25.8 , Ce 0.002 Li 1.45 Lu 6.298 Y 2.5 Si 6 O 25.8 , Ce 0.0015 Li 1.3 Lu 8.3985 La 0.5 Si 6 O 25.9 .
[0188] While the foregoing description represent the preferred embodiments of the present invention, it will be understood that various additions and/or substitutions may be made therein without departing from the spirit and scope of the present invention. One skilled in the art will appreciate that the invention may be used with many modifications of structure, forms, arrangement, proportions, materials, and components and otherwise, used in the practice of the invention and which are particularly adapted to specific environments and operative requirements, without departing from the principles of the present invention. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive. | Inventions relate to scintillation substances and they may be utilized in nuclear physics, medicine and oil industry for recording and measurements of X-ray, gamma-ray and alpha-ray, nondestructive testing of solid states structure, three-dimensional positron-emission tomography and X-ray computer tomography and fluorography. Substances based on silicate comprising lutetium and cerium characterised in that compositions of substances are represented by chemical formulae Ce x Lu 2+2y−x Si 1−y O 5+y , Ce x Li q+p Lu 2−p+2y−x−z A z Si 1−y O 5+y−p , Ce x Li q+p Lu 9.33−x−p−z □ 0.67 A z Si 6 O 26−p , where A is at least one element selected from group consisting of Gd, Sc, Y, La, Eu, Tb, x is value between 1×10 −4 f.units and 0.02 f.units., y is value between 0.024 f.units and 0.09 f.units, z is value does not exceeding 0.05 f.units, q is value does not exceeding 0.2 f.units, p is value does not exceeding 0.05 f.units. Achievable technical result is the scintillating substance having high density, high light yield, low afterglow, and low percentage loss during fabrication of scintillating elements. | 2 |
FIELD OF THE INVENTION
The present invention relates to a method for determining the rotary speed of a compressor, e.g., a turbocharger of an internal combustion engine, as well as to a computer program and/or a control device for controlling an internal combustion engine.
BACKGROUND INFORMATION
In internal combustion engines, e.g., gasoline or Diesel piston engines, to increase the performance, the air charge in a combustion chamber of the internal combustion engine is increased by the use of a compressor, such as an exhaust gas turbocharger. The pressure with which the air is pressed into the combustion chamber of the internal combustion engine is also designated as boost pressure, and is generally measured in the vicinity of the combustion chamber by a pressure sensor. The pressure signal is supplied to a closed control loop which controls the exhaust gas turbocharger and thereby sets a desired boost pressure.
Exhaust-gas turbochargers have a characteristic time constant, and thus they react comparatively sluggishly to changed control signals, which makes the regulation of the boost pressure more difficult. Therefore, it is advantageous if a direct state variable of the exhaust gas turbocharger that is to be regulated is recorded, e.g., the rotary speed of the compressor of the turbocharger, which is particularly suitable for this purpose.
It is an object of the present invention to provide a method which makes possible a cost-effective and reliable recording of the rotary speed of a compressor.
SUMMARY OF THE INVENTION
In an example method according to the present invention, the pressure sensor that is utilized for the determination of the boost pressure is also used for determining the rotary speed of the compressor. This is based on the recognition that usual compressors do not convey the air continuously, but in a “gushing manner” with respect to a certain location downstream from the compressor. This is caused by the fact that, for example, in an axial compressor, each time that a vane of the compressor wheel passes a certain position, the speed, and thereby also the pressure, of the conveyed air changes. This leads to periodic pressure fluctuations, at least at certain locations downstream from the compressor, whose periodicity is related to the rotary speed of the compressor. This relationship is utilized, according to the present invention, to obtain the rotary speed of the compressor.
As a result, a non-contact method for ascertaining the rotary speed of the compressor is made available, which works on a very robust, basic physical principle and is therefore highly reliable. In addition, in accordance with the method of the present invention, the efficiency of the intake systems of the internal combustion engine and the exhaust gas turbocharger is not reduced, since no additional sensor system is required in comparison to the usual numbers of sensor systems deployed in internal combustion engines. Also, because of the non-contact measurement, if there is any wear, it is slight. Finally, pressure sensors are comparatively simple and inexpensive types of sensor whose signals are able to be simply processed.
Directly downstream from the compressor, the periodic fluctuations in the pressure, which are important to the method according to the present invention, and thus also the recorded pressure signals, are particularly concise, which simplifies the evaluation and thus also the determination of the rotary speed. The costs of assembly are reduced even more if the pressure sensor is integrated into a control component of the compressor, e.g., a pop-off valve. Such a pop-off valve is used as a bypass of the compressor, which is opened in response to the closing of a throttle valve of the internal combustion engine, in order to enable as fast a pressure reduction as possible.
For the separation of the periodic fluctuations from the pressure signal, high-pass filtering can be used, which is simple to implement in software technology. From the separated periodic fluctuations, which are also designated as “alternating components” of the pressure signal, the frequency is able to be ascertained in a simple manner, e.g., by a Fourier transform. By dividing the frequency by the number of vanes of the compressor, or rather, of the compressor wheel, one directly obtains the rotary speed of the compressor.
From the signal of the pressure sensor, not only can the rotary speed of the compressor be obtained, but the boost pressure can also be ascertained, which is an important operating variable for the control of an internal combustion engine. The corresponding pressure value is simply obtained by an averaging of the pressure signal, for instance by low-pass filtering.
However, since the pressure sensor is situated advantageously in the vicinity of the compressor, and since there are various other components between the compressor and the combustion chambers, e.g., a charge-air cooler and a throttle valve, in such a case, the average value of the pressure signal does not correspond to the charge air that is of interest for the control of the internal combustion engine. However, the desired value of the charge air can be obtained in a simple way by correcting the average value of the pressure signal appropriately.
The correction factors used for this are ascertained in preliminary tests, for instance, on a test stand, for the specific type of internal combustion engine. The accuracy of the method is able to be improved in the process if at least one correction factor is used that is a function of a current operating variable of the internal combustion engine, e.g., of an air mass throughput or an air volume throughput.
Because of the position of the pressure sensor in the immediate vicinity of the compressor, its pressure signal can also be used for the functional monitoring of an air filter. For this purpose, the difference between the ascertained pressure and the pressure of an environmental pressure sensor is ascertained. If the pressure reduction exceeds a certain measure, the air filter should be replaced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic representation of an internal combustion engine having an exhaust gas turbocharger and a pressure sensor according to the present invention.
FIG. 2 shows a schematic flowchart of an example method for evaluating the signals made available by the pressure sensor shown in FIG. 1 .
FIG. 3 shows a schematic representation of another example embodiment of an internal combustion engine having an exhaust gas turbocharger and a pressure sensor according to the present invention.
DETAILED DESCRIPTION
In FIG. 1 , an internal combustion engine in its entirety is designated by reference numeral 10 . Although internal combustion engine 10 shown in FIG. 1 is designed as a gasoline internal combustion engine having intake manifold injection, however, important basic contents of the following description apply in exactly the same way to Diesel internal combustion engines, as well as to internal combustion engines having direct fuel injection.
The internal combustion engine 10 includes a plurality of cylinders, of which at present only one is shown, which includes a combustion chamber 12 . Combustion air reaches the latter through an intake valve 14 via an intake duct 16 . Into this fuel is injected, immediately upstream of intake valve 14 , by an injector 18 , which is connected to a fuel system 20 . Upstream of the latter, there is a throttle valve 21 in intake duct 16 .
A fuel-air mixture present in combustion chamber 12 is ignited by a spark plug 22 , which is connected to an ignition system 24 . Hot combustion exhaust gases are carried off from combustion chamber 12 through an exhaust valve 26 and an exhaust pipe 28 . In the exhaust pipe there is a turbine 30 , which is able to be bypassed via a bypass valve 32 .
A compressor 34 is situated in intake duct 16 , which is mechanically connected to turbine 30 . Turbine 30 and compressor 34 together form an exhaust gas turbocharger 36 . For the compression of air, compressor 34 has a plurality of compressor vanes or compressor blades, which are not shown in FIG. 1 , however. The intake air heated by the compression is cooled by a charge-air cooler 38 , which is situated in intake duct 16 , between compressor 34 and throttle valve 21 .
The operation of internal combustion engine 10 is controlled and regulated by a control and regulating device 40 . In particular, throttle valve 21 , injector 18 , ignition system 24 and bypass valve 32 are controlled by control and regulating device 40 . The latter receives signals from various sensors, such as from an HFM sensor 42 which records the air mass flowing through intake duct 16 upstream of compressor 34 , and from a pressure sensor 44 , which records the current pressure in intake duct 16 immediately downstream from compressor 34 .
The combustion air supplied to combustion chamber 12 is compressed by compressor 34 , which makes possible a greater performance of internal combustion engine 10 . The pressure of the air charge pressed into combustion chamber 12 (the “boost pressure”) is made available by pressure sensor 44 in a manner that will be shown below, and is adjusted in a closed control loop by control and regulating device 40 . To do this, the performance of turbine 30 (and thereby the performance of compressor 34 ), is varied by opening bypass valve 32 more or less.
In order to achieve regulation of the boost pressure that is as rapid and precise as possible, the boost pressure is regulated not only based on the boost pressure made available by pressure sensor 44 , but also based on the current rotary speed of compressor 34 . Boost pressure p L and rotary speed n ATL are ascertained starting from a signal U p that is made available by pressure sensor 44 , with the aid of a method which will now be explained with reference to FIG. 2 .
First of all, output signal U p of pressure sensor 44 is submitted in 46 to an A/D conversion. Then, in 48 , periodic fluctuations (“alternating components”) U n of signal U p are separated. These periodic fluctuations U n are brought about by the pressure waves of compressor 34 , which are caused by the individual compressor vanes or compressor blades of compressor 34 . In order for the periodic fluctuations of compressor 44 to be able to be recorded, it is necessary to situate pressure sensor 44 comparatively close to compressor 34 , as shown in FIG. 1 . Besides that, pressure sensor 44 has to have appropriate dynamics.
The periodic fluctuations separated by the high-pass filter in 48 are now submitted in 50 to a Fourier transformation, by which frequency F of the periodic fluctuations is ascertained. This frequency F is the product of rotary speed n ATL and the number n S of the compressor blades or compressor vanes. Therefore, in 52 , ascertained frequency F is divided by the number n S of the compressor blades, which finally leads to the rotary speed n ATL of compressor 34 .
As was mentioned above, signal U p of pressure sensor 44 is also used to ascertain boost pressure P L which prevails immediately upstream of intake valve 14 and in combustion chamber 12 itself. For this purpose, signal U p is submitted to a low-pass filtering in 54 , which leads to an average value U p—m of pressure signal U p . This average value U p—m is equivalent to the pressure between compressor 34 and boost pressure cooler 38 . In order to obtain from this the pressure immediately upstream of intake valve 14 , the value U p—m is submitted to a correction in 56 , by applying to it, in a multiplicative or additive way, at least one correcting factor, here designated as K.
Correcting factor K is determined during the design of the parameters of control and regulating device 40 , for instance, on an engine test stand, by measuring the pressure before and after boost pressure cooler 38 at different operating states of internal combustion engine 10 . Correcting factor K may, in turn, be a function of operating variables of internal combustion engine 10 , for instance, of air mass throughput dm/dt, which is recorded by HFM sensor 42 .
FIG. 3 depicts an alternative example embodiment of an internal combustion engine 10 . In this context, it should be noted that such elements and regions which have equivalent functions to elements and regions in FIG. 1 are not explained again in detail.
In internal combustion engine 10 shown in FIG. 3 , pressure sensor 44 is not situated directly in intake duct 16 , downstream from compressor 34 , but is integrated, together with a pop-off valve 58 , in a unit 60 . Pop-off valve 58 opens when throttle valve 21 is closed, in order to make possible a rapid reduction in pressure in intake duct 16 .
In FIG. 3 , upstream of HFM sensor 42 in intake duct 16 , an air filter 62 is also situated, and upstream of it, in turn, an environmental pressure sensor 64 is present. As may be seen in FIG. 2 , its signal U u , together with averaged signal U p—m , which is obtained using pressure sensor 44 , is fed to a comparison block 66 . If it is determined that the difference between these two signals, or rather the pressure values determined from them, exceeds a boundary value, a measure is carried out in 68 . This measure may be, for instance, an entry into a fault memory, by which it is signaled, during a maintenance procedure, that air filter 62 has been used up or clogged, and has to be replaced. | A method for determining the rotary speed of a compressor, e.g., a turbocharger of an internal combustion engine, includes detecting the pressure in a region that is downstream from the compressor and generating a corresponding pressure signal. The rotary speed of the compressor is obtained from periodic fluctuations of at least one component of the pressure signal. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 11/619,928, filed Jan. 4, 2007, now U.S. Pat. No. 7,694,719 which is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates generally to microprocessor and integrated circuits, and relates more particularly to the cooling of integrated circuit (IC) chips.
BACKGROUND OF THE INVENTION
Recent years have seen an evolution toward higher-power microprocessor, graphics, communication and memory semiconductor chips. This evolution in turn has driven interest in highly conductive solder thermal interface (STI) materials and liquid metal thermal interface (LMI) materials to provide improved thermal coupling between a chip and a heat sink. In both cases, it is an essential function of the thermal interface material that it thermally couple and adhere both to the chip and to the heat sink, in order to reduce the occurrence of failure in use (e.g., due to poor heat transfer between the chip and the heat sink).
A distinguishing feature of STI materials (which are understood to include low-melt solder materials that are solid at room temperature but may at least partially melt at normal chip process temperatures) is that they are composed of metal or metal alloys, such as gallium, indium, tin, lead or bismuth, among others. In some cases, these materials can attack or diffuse into other materials such as aluminum or copper, which are common heat sink materials. In other cases, these materials may fail to wet other materials such as silicon, silicon dioxide, silicon nitride or the like, which are common chip materials. De-wetting or degradation of the interface between the STI material and the heat sink, or between the STI material and the chip, can produce local hot spots that impede the thermal performance or cause outright failure of the chip in high-power applications. It is therefore desirable to provide a wetting or adhesion layer between a thermal interface material and a chip and/or between a thermal interface and a heat sink that maintains barrier properties and also isolates these mating surfaces from corrosive and adverse intermetallic formation with the interface metal.
Finally, both STI and LMI interfaces are conventionally applied in liquid phase. This requires the management of containment, void formation and intermetallic formations that are characteristic of liquid phase interactions. This is often difficult or impractical to achieve. Moreover, in cases where melting points exceed 125 degrees Celsius, attaching a heat sink would likely result in component failure.
Thus, there is a need for a metal thermal interface that provides good thermal coupling between a chip and a heat sink without the complicating need to enter liquid phase.
SUMMARY OF THE INVENTION
The present invention is a patterned metal thermal interface. In one embodiment a system for dissipating heat from a heat-generating device includes a heat sink having a first surface adapted for thermal coupling to a first surface of the heat generating device and a thermal interface formed a soft metal and having at least one patterned surface, the thermal interface being adapted to thermally couple the first surface of the heat sink to the first surface of the heat generating device. Patterning refers to an arrangement of local thick and thin spots on an otherwise flat foil or sheet of metal interface material. Many patterns are possible, and the precise distribution of thick and thin spots is chosen based on the application to give statistical uniformity. The patterned surface of the thermal interface allows the thermal interface to deform under compression between the heat sink and the heat generating device, leading to better conformity of the contact points of the thermal interface to the surfaces of the heat sink and the heat generating device.
The size and distribution of the thick and thin spots in the patterning is selected to account for the bow, warp and other surface properties of the heat generating device and of the heat sink. For instance, in an exemplary embodiment, the relative thickness between the thick and thin spots on the patterned thermal interface is 150 micron, with 200 micron pitch in a rectangular periodic array for an expected heat sink warping of approximately fifty micrometers
During compression of the thermal interface (e.g., between the heat-generating device and the heat sink) the surface patterning of the thermal interface allows for local high pressure points uniformly distributed over the surface to be thermally coupled. This pressure causes the soft metal to creep and conform microscopically to the surfaces being thermally coupled, thereby providing good thermal contact at these points. Thermal coupling is further enhanced by the breakup of surface oxides, allowing metallic bonds to form at contact points between the metal interface material and the metal of the surfaces being thermally coupled. In one embodiment, moderate heat (e.g., not in excess of the thermal interface's melting point) is applied to accelerate the creep process. Embodiments of the invention intend that the thermal interface metal remain in solid phase during application and use.
In one embodiment, surface oxides of the thermal interface and of the contact surfaces of the heat generating device and the heat sink are managed in any one or more of a variety of ways. For example, in one embodiment, the thermal interface is fabricated immediately prior to use in order to limit the thickness of surface oxide. In another embodiment, at least one of the contact surfaces of the heat generating device, the heat sink and the thermal interface is treated with at least one of: an acid, a base, a plasma clean, a chemical cleaning agent or a mechanical abrasive. The treatment removes surface oxides prior to join or assembly of the heat sink assembly components. In another embodiment at least one of the contact surfaces of the heat generating device, the heat sink and the thermal interface is treated with at least one of: hydrochloric acid, oxalic acid, acetic acid, isopropyl alcohol, methyl alcohol, ethyl alcohol, acetone, and xylene. In yet another embodiment, at least one of the contact surfaces of the heat generating device, the heat sink and the thermal interface is treated with at least one of: sand blasting, sand paper, metal wool, cryogenic clean, and burnishing. In another embodiment still, at least one of the contact surfaces of the heat generating device, the heat sink and the thermal interface is treated with at least one of: reactive ion etch, plasma ashing, chemical down stream etching.
Since most heat sinks are clamped to heat-generating devices with significant force (e.g., 20 pounds or more) in order to compress thermal greases, the patterned metal thermal interface provides a practical high performance alternative with little or no change to existing assemblies. Pressure and optional heating are present during the application of the patterned metal interface. Once the thermal interface has been applied and bonded to the heat-generating device and to the heat sink, optional maintenance of pressure leads to better mechanical stability and robustness of the assembly. Reducing the amount of surface oxide on all mating surfaces of the heat-generating device and the heat sink prior to assembly further improves the thermal performance of the thermal interface.
The patterned metal thermal interface is intended as a general thermal interface solution. One particular area in which the thermal interface of the present invention may find use is between a computer chip comprised of silicon (and typically coated with silicon dioxide or silicon nitride) and a heat sink comprised of copper, nickel-plated copper or aluminum. A second area in which the thermal interface of the present invention may find use is between a lidded computer chip and a heat sink (similar to the heat sink described above), where the lid of the computer chip is comprised of copper or nickel-plated copper. Thus, the mating surfaces to be thermally coupled will, in many cases, be comprised of copper, nickel or silicon. In one embodiment, where the patterned metal thermal interface is comprised of indium or tin, the thermal interface can be directly applied to copper, nickel and silicon surfaces. In another embodiment, where the patterned metal thermal interface is comprised of silicon, a surface metallization is optionally applied to promote bonding and improve the thermal contact performance. If pressure is maintained during use, surface metallization of the thermal interface is not absolutely necessary, but will improve the thermal performance and reduce corrosion susceptibility.
In the most minimal embodiment, a patterned metal sheet is placed between heat-generating device and a heat sink and compressed with little or no surface preparation. For example, a patterned indium foil of approximately 200 micron thickness can be placed between a copper heat sink and a nickel-plated lidded computer chip in an assembly that exerts pressure on the foil sufficient to cause creep in the foil. In this configuration, there would be little bonding due to surface oxides, and both the thermal performance and the corrosion resistance of the thermal interface would be less than optimal. However, this performance is acceptable in most use cases. The thermal interface material will continue to creep during operation and is enhanced by the heat of operation. Creep will continue until an asymptotic stability is reached.
In addition to the thermal advantages of using the patterned metal thermal interface, there are advantages in rework. One of the most common thermal interface materials in use today is thermal grease. Thermal grease comprises oil containing thermally conductive particles. Thermal grease is extremely messy and difficult to clean during rework. The patterned metal thermal interface, by contrast, is dry and convenient to remove during rework by simply separating the heat sink from the heat-generating device and peeling or lightly scraping the patterned metal thermal interface off of the coupled surfaces.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited embodiments of the invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 is an exploded view of a heat sink assembly using a patterned metal thermal interface, according to one embodiment of the present invention;
FIG. 2 is a plan view illustrating one embodiment of the thermal interface illustrated in FIG. 1 , according to the present invention;
FIG. 3 is a flow diagram illustrating one embodiment of a method for assembling a heat sink assembly, according to the present invention;
FIG. 4 is a schematic diagram illustrating one embodiment of the assembled heat sink assembly illustrated in FIG. 1 , where the heat sink assembly is assembled according to the method illustrated in FIG. 3 ;
FIG. 5 is a flow diagram illustrating a second embodiment of a method for assembling a heat sink assembly, according to the present invention;
FIG. 6 is a schematic diagram illustrating one embodiment of the assembled heat sink assembly illustrated in FIG. 1 , where the heat sink assembly is assembled according to the method illustrated in FIG. 5 ; and
FIG. 7 is an exploded view illustrating one embodiment of a heat sink assembly, in which the adhesion/wetting/bonding layers comprise an insert or film that is separately formed and then applied to the heat sink assembly.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.
DETAILED DESCRIPTION
In one embodiment, the present invention is a thermal interface for use in dissipating heat from heat-generating devices (e.g., microprocessor chips). Embodiments of the present invention provide improved heat transfer from a heat generating device to a heat sink, thereby allowing for better heat dissipation from the heat generating device. This ultimately results in better performance of the heat generating device, as heat-related failures are minimized.
FIG. 1 is an exploded view of a heat sink assembly 100 using a patterned metal thermal interface 102 , according to one embodiment of the present invention. As illustrated, the heat sink assembly 100 comprises the thermal interface 102 disposed between a heat generating device 104 (e.g., a microprocessor chip or a lidded chip) and a heat sink 106 . Alternatively, the heat sink 106 may be a lid where the heat generating device 104 is a microprocessor or semiconductor chip.
The heat sink 106 comprises a base 108 having first surface 108 a and a second surface 108 b . In one embodiment, the heat sink 106 comprises at least one of: a vapor chamber, a heat pipe or a liquid cooler. The first surface 108 a of the base 108 is relatively flat and is configured to contact the thermal interface 102 . To this end, the first surface 108 a optionally comprises a first interface metallization layer 110 . In one embodiment, the first interface metallization 110 layer comprises an adhesion layer and a wetting layer (i.e., such that the adhesion layer is “sandwiched” between the wetting layer and the first surface 108 a of the base 108 ). For example, one embodiment of the first interface metallization layer 110 comprises a film of gold (wetting layer) deposited over a film of titanium (adhesion layer). In further embodiments, the adhesion layer comprises at least one of: titanium, a titanium-tungsten alloy, chromium, nickel, molybdenum or tantalum. In further embodiments, the wetting layer comprises at least one of: platinum, gold, an oil or an organic material. In a further embodiment, the first interface metallization layer 110 has a total thickness of approximately 2500 Angstroms, where the adhesion layer accounts for approximately 2000 Angstroms and the wetting layer accounts for approximately 500 Angstroms.
Many other embodiments of the first interface metallization layer 110 are possible. In one embodiment, the materials (i.e., for the adhesion and wetting layers) and thickness of the first interface metallization layer 110 are chosen such that: (1) the adhesion layer substantially adheres to the first surface 108 a of the base 108 ; (2) the adhesion layer substantially isolates first surface 108 a of the base 108 from chemical interaction; (3) the adhesion layer does not form substantial adverse intermetallics with the thermal interface 102 ; (4) the adhesion layer forms a metallic bond with the thermal interface 102 under heat and pressure; (5) the wetting layer substantially prevents oxide formation on the adhesion layer; (6) the wetting layer substantially adheres to the adhesion layer; and (7) the wetting layer is substantially malleable and bonds to the thermal interface 102 . The respective thicknesses of the adhesion layer and the wetting layer are chosen with knowledge of the deposition process (e.g., sputtering, evaporation, jet process, etc.) to provide adhesion, coverage and low film stress.
Thus, in practice, the first interface metallization layer 110 provides a surface that is able to be bonded to a heat-generating device. Moreover, it is noted that in the case of metallic thermal interfaces, the more noble the metals that the thermal interface 102 is sandwiched between, the less susceptible the thermal interface 102 is to corrosion.
In a further embodiment, a transition layer is provided between the adhesion or barrier layer portion of the first interface metallization layer 110 and the wetting layer in order to create a diffuse boundary.
In a further embodiment, the first interface metallization layer 110 comprises a single metallic coating. For example, in one embodiment, the single coating comprises one of: gold, platinum, nickel, chrome or tungsten. In one embodiment, the material comprising the first interface metallization layer 110 is a more noble material than the material comprising the thermal interface 102 . This is particularly advantageous in cases where bonding of the thermal interface 102 to the heat sink 106 and/or heat-generating device 104 is not required, and the heat sink assembly 100 is to be clamped with reasonable mechanical force for the duration of its useful lifetime.
In one embodiment, one or more of the surfaces of the heat sink 106 , heat-generating device 104 and thermal interface 102 is coated with a bonding agent, such as an organic polymer adhesive, an epoxy resin or an oil. For example, in one embodiment, a thin (e.g., 100 nm) coating of epoxy is applied to the heat sink 106 and to the heat-generating device 104 . The thermal interface 102 is then placed between the heat-generating device 104 and the heat sink 106 , and mechanical force and heat are applied to compress the thermal interface 102 and to cure the bonding agent.
In another embodiment, no such coating is used. In this case, the thermal interface 102 is compressed between the heat-generating device 104 and the heat sink 106 . This embodiment is advantageous in less hostile environments, where corrosion is less of a concern. This embodiment is also advantageous when the heat sink assembly 100 is to be clamped with mechanical force for the duration of its useful lifetime, but the advantages are not limited to this situation. For instance, advantages to the no coating embodiment may be realized where the heat sink 106 and the heat-generating device are made of compatible metals, and particularly where some degree of bonding can take place. A specific example is a patterned indium thermal interface compressed between a copper heat sink and a nickel-coated heat-generating device. In this example, best results occur when care is taken to remove or minimize surface oxides prior to compression, and when heat is applied during initial compression as described further herein.
In one embodiment, the second surface 108 b of the base 108 is also relatively flat and comprises a plurality of fins 112 1 - 112 n (hereinafter collectively referred to as “fins 112 ”) coupled thereto. The fins 112 are positioned in a substantially perpendicular orientation relative to the base 108 .
The heat generating device 104 also comprises a first surface 104 a and a second surface 104 b . In one embodiment, both the first surface 104 a and the second surface 104 b of the heat generating device 104 are relatively flat. The first surface 104 a of the heat generating device 104 further comprises a second interface metallization layer 114 . In one embodiment, the second interface metallization layer 114 is constructed in a manner similar to the first interface metallization layer 110 and comprises an adhesion layer and a wetting layer. In a further embodiment, a transition layer is provided between the adhesion layer of the second interface metallization layer 114 and the wetting layer in order to create a diffuse boundary.
The thermal interface 102 comprises a patterned metal foil, a metal mesh or a perforated metal sheet. The metal of the thermal interface is a solid metal (i.e., solid in phase). The foil is comprised of a relatively soft metal that deforms readily under moderate pressure. In one embodiment, the foil is comprised of at least one of: indium, lead, gold, silver, bismuth, antimony, tin, thallium or gallium. In another embodiment, the thermal interface 102 is comprised of a soft metal mesh. The thermal interface 102 is patterned or textured; that is, the thermal interface 102 exhibits a substantially uniform thickness and flatness but with local topography (high and low spots). In a further embodiment, the thermal interface 102 has a thickness of approximately 150 microns.
FIG. 2 is a plan view illustrating one embodiment of the thermal interface 102 illustrated in FIG. 1 , according to the present invention. As illustrated, the surface of the thermal interface 102 is patterned or textured. In one embodiment, the pattern carried on the thermal interface 102 comprises one of many potential patterns. In one embodiment, the pattern has a topography that comprises high spots (e.g., spot 200 ) and low spots (e.g., spot 202 ). In a further embodiment, the pattern has a topology that allows for at least approximately fifty percent compression of the thermal interface 102 when the thermal interface 102 is pressed between a heat generating device and a heat sink. For example, in one embodiment, the pattern is a waffle pattern. In another embodiment, the pattern is a line pattern. In yet another embodiment, the pattern comprises at least approximately 100 microns of topology in parallel grooves, with approximately 0.5 mm pitch.
The use of the patterned thermal interface illustrated in FIGS. 1 and 2 provides improved heat transfer from the heat generating device 104 to the heat sink 106 , thereby allowing for better heat dissipation from the heat generating device 104 . Specifically, when pressed between the heat generating device 104 and the heat sink 106 , the patterned thermal interface 102 deforms, allowing the thermal interface 102 to conform to the first surface 104 a of the heat generating device 104 and to the first surface 108 a of the heat sink base 108 . Thus, heat generated by the heat generating device 104 is transferred to the base 108 of the heat sink 106 , via the patterned thermal interface 102 . The base 108 then spreads the heat to the fins 112 of the heat sink 106 , from which the heat is carried by forced air (generated, e.g., by fans, not shown). The better the thermal coupling between the heat generating device 104 and the heat sink 106 , the more heat that is dissipated by the heat sink assembly 100 .
FIG. 3 is a flow diagram illustrating one embodiment of a method 300 for assembling a heat sink assembly, according to the present invention. The method 300 may be implemented, for example, to assemble a heat sink assembly such as the heat sink assembly 100 illustrated in FIG. 1 .
The method 300 is initialized at step 302 and proceeds to step 304 , where the method 300 coats a first surface of a heat generating device with an adhesion film. The adhesion film comprises a film of material that does not alloy to an appreciable extent with the material of the thermal interface. In one embodiment, the adhesion film comprised at least one of: titanium, a titanium-tungsten alloy, chromium, nickel, molybdenum or tantalum. In one embodiment, the adhesion film is vacuum deposited. The method 300 then proceeds to step 306 and coats the adhesion film with a wetting film. In one embodiment, the wetting film comprises at least one of: gold or platinum. In one embodiment, the wetting film is vacuum deposited, in order to limit the amount of oxygen present when the wetting film material is applied to the adhesion film. The adhesion and wetting films together provide an interface metallization layer for the heat generating device. In an alternative embodiment, the adhesion/wetting film can be bulk evaporated or sputtered in reverse order onto a backing material (e.g., a polyimide) and then bonded (via pressure and/or heat) to the first surface of the heat generating device using a bonding agent (e.g., epoxy). The backing material would then be peeled away to reveal the wetting film surface. In this embodiment, care is taken to achieve a bond line of approximately 250 nanometers. Further embodiments include applying the adhesion/wetting film by plating, plasma spray or jet process.
In step 308 , the method 300 coats a first surface of a heat sink with an adhesion film. In one embodiment, the adhesion film is vacuum deposited. The method 300 then proceeds to step 310 and coats the adhesion film with a wetting film. In one embodiment, the wetting film is vacuum deposited, in order to limit the amount of oxygen present when the wetting film material is applied to the adhesion film. The adhesion and wetting films together provide an interface metallization layer for the heat generating device. In an alternative embodiment, the adhesion/wetting film can be bulk evaporated or sputtered in reverse order onto a backing material (e.g., a polyimide) and then bonded (via pressure and/or heat) to the first surface of the heat sink using a bonding agent (e.g., epoxy). The backing material would then be peeled away to reveal the wetting film surface. In this embodiment, care is taken to achieve a bond line of approximately 250 nanometers.
In step 312 , the method 300 positions a patterned metal thermal interface (such as the thermal interface illustrated in FIGS. 1 and 2 ) between the heat generating device and the heat sink. Specifically, the thermal interface is positioned between the first surface of the heat generating device and the first surface of the heat sink, both of which have been coated with an interface metallization layer as described above. In an alternative embodiment, the patterned metal thermal interface is pre-applied to the heat sink (e.g., by the heat sink manufacturer) prior to assembly in accordance with the method 300 . In this case, the thermal interface may be patterned as part of the joining process to the heat sink (e.g., with a die or heated die). In one embodiment, the thermal interface is comprised of an indium foil. In one embodiment, the thermal interface has a thickness in the range of approximately 100 to 200 microns (e.g., approximately 150 microns). In one embodiment, the thermal interface is processed prior to deployment in the heat sink assembly in order to minimize surface oxides. In one embodiment, this processing involves rolling and patterning the thermal interface just prior to deployment to expose the oxide free metal. In another embodiment, the processing involves treating the thermal interface with a dilute acid, such as hydrochloric acid.
In step 314 , the method 300 applies pressure to the heat sink assembly (i.e., the heat generating device, the heat sink and the thermal interface), in order to compress the thermal interface between the heat generating device and the heat sink. This pressure deforms the patterned thermal interface, allowing the thermal interface to conform to the first surface of the heat generating device and the first surface of the heat sink at a near-atomic scale. In one embodiment, the amount of pressure applied to the heat sink assembly is on the order of approximately ten to twenty kg/cm 2 . In one embodiment, the heat sink is further held in place using screws, polymer glue, clips or other appropriate fastening means.
In optional step 316 (illustrated in phantom), the method 300 applies heat to the heat sink assembly. The application heat in addition to the continued application of pressure accelerates the alloying of the wetting film with the thermal interface material, resulting in a solid joint of the thermal interface material and the adhesion film material. In one embodiment, the heat applied to the heat sink assembly is in the range of approximately forty degrees Celsius to approximately 135 degrees Celsius. For example, in one embodiment, the heat applied to the heat sink assembly is on the order of approximately eighty-five degrees Celsius.
The method then terminates in step 320 .
The method 300 thereby produces a heat sink assembly in which intimate contact is maintained between the thermal interface and the heat generating device, and between the thermal interface and the heat sink. In one embodiment, this contact comprises a continuous material connection that is mechanically and thermally stable due to the metallurgic effects of the pressure and heat applied thereto. During operation of the heat generating device, the thermal interface will typically remain clamped and under modest pressure between the heat generating device and the heat sink.
When fully compressed, the thermal interface will likely exhibit small breaks perpendicular to the interface plane as a result of incomplete collapse of the pattern carried on the thermal interface. These breaks allow the thermal interface material to expand and contract in response to thermal stresses, without generating large shear forces relative to the heat generating device and the heat sink. Thus, such discontinuities allow the conformed thermal interface to tolerate expansion differences between itself, the heat generating device and the heat sink, all of which are generally comprised of different materials having different thermal expansion properties.
In an alternative embodiment, rather than coating the surfaces of the heat generating device and the heat sink with the interface metallization layers, a bonding agent (e.g., epoxy) is applied to one or more of: the thermal interface, the first surface of the heat generating device and the first surface of the heat sink. The components are assembled, and the interface is then pressed and cured by the application of the heat. In this case, a thin bond line (e.g., approximately 250 nanometers or less in thickness) is maintained. In a further embodiment, the heat sink is first cleaned of most surface oxides before bonding, and heat is applied for a period of hours (e.g., approximately ten to twenty hours) at a temperature in the range of approximately forty degrees Celsius to approximately 135 degrees Celsius (e.g., approximately ninety degrees Celsius). Bonding provides the advantages of convenience, speed and simplicity; however, coating with an interface metallization layer provides better resistance to corrosion.
Those skilled in the art will appreciate that many materials other than titanium and gold may be used to form the interface metallization layer. In general, any material or combination of materials that provides: (1) good adherence to the heat generating device and the heat sink; (2) limited solubility and limited intermetallic activity with respect to the thermal interface material; (3) limited surface oxidation (potentially achieved by capping a first material with a noble metal); and (4) ready alloying to the thermal interface material (again potentially achieved by capping a first material with a noble metal).
FIG. 4 is a schematic diagram illustrating one embodiment of the assembled heat sink assembly 100 illustrated in FIG. 1 , where the heat sink assembly 100 is assembled according to the method 300 illustrated in FIG. 3 . As illustrated, the thermal interface 102 is compressed between the heat generating device 104 and the heat sink 106 such that the thermal interface conforms to the surfaces of the heat generating device 104 and the heat sink 106 .
FIG. 5 is a flow diagram illustrating a second embodiment of a method 500 for assembling a heat sink assembly, according to the present invention. The method 500 may be implemented, for example, to assemble a heat sink assembly such as the heat sink assembly 100 illustrated in FIG. 1 .
The method 500 is initialized at step 502 and proceeds to step 504 , where the method 500 positions a thermal interface between a first surface of a heat generating device and a patterned first surface of a heat sink. In one embodiment, the thermal interface comprises a substantially flat, smooth metal foil. In one embodiment, the foil is comprised of indium. The first surface of the heat sink is patterned with a relief structure.
In step 506 , the method 500 applies pressure to the heat sink assembly, such that the thermal interface is compressed between the first surface of the heat generating device and the first surface of the heat sink. Compression causes the first surface of the heat sink to impress the pattern carried thereon into the thermal interface, locally deforming the thermal interface and allowing the thermal interface to conform to the first surface of the heat generating device and the first surface of the heat sink at a near-atomic scale. In one embodiment, the heat sink is further held in place using screws, polymer glue, clips or other appropriate fastening means.
In optional step 508 (illustrated in phantom), the method 500 applies heat to the heat sink assembly before terminating in step 510 .
An advantage of the method 500 is that is allows direct thermal coupling of vapor chamber heat sinks to high-power semiconductor or microprocessor chips without requiring the high temperatures normally needed for solder attachment. Moreover, compliant metal interfaces may be used without vacuum chip metallization in the case of organic bonding. Ultimately, these advantages result in improved thermal performance in the range of two to five mm 2 C/W.
FIG. 6 is a schematic diagram illustrating one embodiment of the assembled heat sink assembly 100 illustrated in FIG. 1 , where the heat sink assembly 100 is assembled according to the method 500 illustrated in FIG. 5 . As illustrated, the thermal interface 102 is compressed between the heat generating device 104 and the heat sink 106 such that the thermal interface conforms to the surfaces of the heat generating device 104 and the heat sink 106 .
FIG. 7 is an exploded view illustrating one embodiment of a heat sink assembly 700 , in which the adhesion/wetting/bonding layers comprise an insert or film 710 that is separately formed and then applied to the heat sink assembly 700 . As illustrated, the film 710 may be positioned between the thermal interface 702 and a first surface 704 a of the heat generating device 704 . Alternatively, the film 710 may be positioned between the thermal interface 702 and a first surface 708 a of the heat sink 708 . Moreover, the film 710 may be formed with any combination of one or more of the adhesion layer, the wetting layer and the bonding layer.
Thus, a thermal interface is disclosed that provides improved heat transfer from a heat generating device to a heat sink, thereby allowing for better heat dissipation from the heat generating device. This ultimately results in better performance of the heat generating device, as heat-related failures are minimized.
While foregoing is directed to the preferred embodiment of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | The present invention is a patterned metal thermal interface. In one embodiment a system for dissipating heat from a heat-generating device includes a heat sink having a first surface adapted for thermal coupling to a first surface of the heat generating device and a thermal interface having at least one patterned surface, the thermal interface being adapted to thermally couple the first surface of the heat sink to the first surface of the heat generating device. The patterned surface of the thermal interface allows the thermal interface to deform under compression between the heat sink and the heat generating device, leading to better conformity of the thermal interface to the surfaces of the heat sink and the heat generating device. | 8 |
This is a continuation of application Ser. No. 202,809, filed Oct. 31, 1980.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a distributed data processing system having several local systems (LS), each local system having at least one central processing unit (CPU) with its associated memory, peripherals and processes, where the communication between said LS's takes place via a general communications network and where the control of said data processing system is distributed over the respective local systems.
2. Description of the Prior Art
Technological progress made in the field of large scale integrated circuits (LSI) and their low cost are causing an evolution in the architecture and use of data processing systems towards distributed systems. Also, different kinds of processors are beginning to appear, such as processors (CPU) reserved solely for users, special purpose processors (allocation of resources, data base management, communications, etc.) and service processors.
In addition, the local interconnection of data processing systems distributed over the operating areas of an organization, having as objectives communications and the sharing of resources, imply that procedures and protocols are defined which make possible the initialization of the distributed systems, communication between user application programs and the best possible use of resources by sharing phase among said applications. The Appendix contains a selection of references to the prior state of the art.
All the references given in the Appendix are of a general nature. In reference (1) it seems that the distributed control of the overall system is based in each LS which, in this case, is a processor with its main store. References (2) and (3) describe a distributed communications network for packet data transmission in which the user process and resources are distributed. In this system, however, all the processing units are identical and the interconnections between units are made via a "bus" hierarchy. References (4) to (7) describe either distributed processing (4) or distributed control (5 and 6), or the distribution of all the components of a system (7).
SUMMARY OF THE INVENTION
In the present invention, the various functions characteristic of a distributed system are separated from the LS and located in their respective functional layers. By way of example, the communication procedures, are located in the functional communication layer. Certain other coordination, control, initialization functions, etc., are located in the functional coordination layer, which is the subject of the present invention. Other differences between this invention and the prior art aforementioned will be clearly shown in the description of an embodiment.
This invention is designed for use in a distributed system with the following features:
the distributed system is a medium-scale type (MSDS) with the ability to interconnect several tens of local systems by the general communications network and to execute a number of different application programs;
the general communications network used to communicate between the local systems is an optical bus (loop or star);
the transmission rate on the optical bus provides a transfer speed in both directions of 300 kwords/sec (16 bits/word) per local system;
the physical characteristics of the optical bus limit the distribution of the local systems to distances of a few kilometers.
The subject of this invention is limited to the coordination layer managed by the system intercommunication processors (SIP) located between the local systems (LS) and the communications network.
The present invention is characterised in that the communication between said LSs is managed by the SIPs located in a functional coordination layer between each of said LS and a functional communication layer, each of said SIP comprising special hardware and software providing for the functions of coordination, communication, control, initialization and simulation relating to the various LS,
a. said coordination and communication functions further comprising means for the translation of addressing and coding parameters between said LS, means for interrogating, analyzing and localizing resources relating to an LS request, and means for selecting the best resource where there is a choice between several available undedicated resources;
b. said control functions further comprising protective mechanisms controlling the access rights to the resources and objects of each LS at the level of the associated SIP, means for defining the authorized interactions between the applications of said distributed data processing system, means for optimizing the use of resources by sharing them fairly between the applications, means of detecting a failure in a component of said distributed system by monitoring the coherence of messages and by retransmitting the messages in which a loss of information is detected, and means for isolating an LS by disconnection when the transmission or reception of a message is impossible;
c. said initialization functions further comprising means for the remote loading from a pilot LS having remote loading facilities of the read/write memories relative to each of said LS and the corresponding SIP itself, and means for remotely starting from any site the programs loaded into the LS and SIP;
d. said simulation functions further comprising the simulation of commands sent from a control panel comprising means for resetting to an initial state the defined components of said distributed system, loading of initial programs, causing a program to be carried out instruction by instruction, loading and reading the general registers of an LS, interrupting programs being processed and starting special programs.
One of the main objectives of this invention is to take advantage of technology by constructing a system (SIP) specialized in the functions of coordination, communication, control and initialization within the context of a distributed data processing network. The simulation and testing of the SIP design described in this patent application has shown that this invention can provide an optimal solution for a distributed system with the characteristics described above.
Other objectives and advantages of this invention are summarized below.
As the SIPs are the coordinators of the distributed system, they are located in a functional layer which is as close as possible to the communications network in order to provide fast communication of information relating to the capacities and states of the data processing units interconnected during the issue of service requests, to involve in a transaction only the units concerned thereby and to detect any error or fault as rapidly as possible, to prevent their propagation towards the upper layers and to make possible a fast reconfiguration of the overall system.
The transformation of identification parameters retains for each processor or processing unit some degree of autonomy and independence reflected in the existence of their own operating system and storage space.
The localization of resources makes it possible to respond to the requests of each LS in the best possible way. If each SIP knows the state of the local capacities and resources, it will be able to analyze a request when a process asks for a resource, and to give a positive reply if it is in a position to satisfy it.
The facility for selecting the most available resource when there is a choice between several undedicated resources thus reduces waiting time and balances the load on the various units.
The provision of protective mechanisms at the level of each SIP prevents illegal operations on objects or resources by applications which do not possess access right to them.
The definition of the authorized interactions between the applications thus guarantees their protection and may also be used to optimize the use of resources by sharing them equally between the applications.
The failure of a component of the system must be detected as quickly as possible so that it may be isolated and thus prevent the propagation of errors which it could generate. The SIP can analyze the coherence of the requests received and also monitor the behaviour of the various units in relation to the defined procedures and protocols. These methods of analysis must not only prevent any disturbance in the valid sub-assemblies of the system, but also make possible its dynamic reconfiguration in order to keep it operational relative to the whole set of applications to be processed.
The initialization functions give the system flexibility in loading and starting the various units and LS in different conditions, e.g. in the event of errors, the replacement of units for maintenance, etc.
The simulation of the commands of a control panel originating from a remote LS provides for diagnosis and initialization functions on any of the LS.
These advantages and others related to this invention will be clearly shown in the following description of an embodiment. The description refers to the P 800 series of mini and micro-computers manufactured by Philips Data Systems. Only the architecture of the P 800 relevant to this invention (e.g. interface) is described. The detailed descriptions of the P 800 system will be found in the references quoted.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is an overall diagram of a distributed data processing system showing the main sub-systems and functional layers.
FIG. 2 is a flow chart describing the chaining of transactions between two local systems (LS) connected to the communications network.
FIG. 3 is a flow chart describing the communications links between the SIP and the communications module (CM).
FIG. 4 is a block diagram of the SIP showing the main components and their connections.
FIG. 5 is a functional diagram showing the components of the processing module (PM) of the SIP with its connections to the internal bus.
FIG. 6 shows the state sequence of the PM.
FIG. 7 shows the principle of the allocation mechanism of an input/output buffer.
FIG. 8 shows the state sequences of the allocation mechanism between the components concerned.
FIG. 9 shows the state sequences of the local communications module (LCM).
FIG. 10 is an overall structural diagram of the LCM showing the main components controling the exchange mechanism with the LS.
FIG. 11 is a detailed flow chart describing the exchange mechanism between the LCM and the LS.
FIG. 12 is the microprogram relating to the exchange mechanism described in FIG. 11.
FIG. 13 is an overall structural diagram of the CMI (communications interface module) showing the main components used to control the interface between the SIP and the CM.
FIG. 14 shows the state sequences of the CMI control automat.
FIG. 15 is a flow chart describing the initialization, remote loading and remote starting procedures from an LS piloting the other LS in the system.
FIG. 16 is a flow chart describing the processing of a service request by the SIP connected to the communications network.
The SIP auto-selection mechanism is described with reference to FIG. 17.
FIG. 18 shows the response time of a processing unit (CPU) in relation to its load.
The Appendix includes:
(1) a description of the physical interface between the SIP and a local P 800 system;
(2) a description of the physical interface between the SIP and the CM;
(3) a list of references which may be regarded as the prior art in the context of this invention.
The architecture of the P 800 mini and microcomputers is decribed in the following documents published by Philips Data Systems:
P 856M/P 857M, CPU Service manual 5111-991.2695X
P 856M/P 857M, System handbook 5122-991-26931
P 851M, Vol. I CPU and memories technical manual 5122-991-28073.
DESCRIPTION OF THE PREFERRED EMBODIMENT
On FIG. 1, 10 represents the various local systems (LS1 . . . LS I . . . LS N ). The SIPs corresponding to each LS are represented by 11 and are all located in the coordination functional layer represented by 12. SIP 11 communicate with communication network 14 (physical transfer) via respective communication modules (CM) 13 located in the communications functional layer (represented by 19). CM's 13 are responsible for monitoring the communications protocols in order to establish communication and ensure that information is validly transferred but this is not explained further for brevity.
An LS 10 may consist of various components, e.g. LS (1) consists of CPU 15, primary read/write and read only stored 16 and processes 17 and 18.
An application or user program may consist of several processes and may be distributed over several LS. Although it is designed for a well defined objective, the SIP by means of suitable initialization hardware and software is totally programmable from the exterior and can therefore easily be adapted for different functions. The characteristics of the MSDS already mentioned limit the flow rate of an LS (and thus of the SIP) to 300 kwords/sec bidirectional. It will be possible to improve the performance of the SIP by replacing the existing components by higher performance ones, e.g. microprocessors, read/write and read only stores, microprogrammed automats etc., but with the same architectural design base (instructions, interface, control, etc.). Hereafter, first the communication mechanisms between the SIP and the LS, the SIP and the communications network via the CM, the instructions used and the connecting blocks are described in a general manner. Next follows a detailed description of the architecture of the SIP. In general, the SIP uses the instructions of a P 800 system.
COMMUNICATION MECHANISMS AND INSTRUCTIONS
Commands (CPU→SIP)
The LS uses an input/output instruction (CIO start) to inform the SIP (by way of synchronization) that a command is being communicated to it. This command may be directly transferred on the P 800 bus if it is no longer than a 16-bit word (register content specified by the CIO) during the execution of the instruction. (The physical interface between the SIP and the P 800 bus is defined in the Appendix.) Otherwise, the address of a control block located in the main store will then be specified (register content indicated by the CIO instruction). This control block contains all the instructions, parameters and data needed to execute the command.
Incoming request (SIP→CPU)
A command issued by an LS may give rise to one or more incoming requests communicated to the other local system(s) concerned.
An incoming request is communicated by the generation of an interrupt to CPU 15 of the LS concerned, which then executes an SST I/O instruction to identify the reason for the interrupt. After the SST instruction has been executed, the register specified by the latter instruction contains the address of an input request block located in the main store 16 and containing all the information pertaining to this request. The SIP uses a memory block previously allocated to it by the LS to receive incoming requests.
Issue of a result (CPU→SIP)
After an incoming request has been processed, the LS sends a result relative to this request to its associated SIP. This result is communicated by means of an I/O instruction (CIO start) executed by the CPU. The register specified by the instruction then contains the address of a result block previously buffered into the main store.
Communication of a result (SIP→CPU)
A result relating to the execution of a command in a local system different from the originating local system will be communicated to the originating LS via an interrupt sent to the CPU which will then execute an SST I/O instruction. The register specified by the SST I/O instruction, after its execution, contains the address of a block in the main store previously loaded with the result in question. The block used will have been allocated when the command was issued by the LS.
FORMAT OF THE RELEVANT 16-BIT INSTRUCTIONS
I/O instruction: CIO start ##STR1##
Bit 1 has always value zero. Bits 2-5 specify the instruction type Bits 6-8 (R1) specify a register; the content thereof either is directly a command or, alternatively, the address in the main store of a command or result block. During the execution of the instruction the content of register R1 is forwarded to the data bus. The two condition register bits (CR) are defined as follows
00 instruction accepted (LBR clear)
01 instruction refused (LBR full)
11 address not recognized
LBR is an intermediate or mail-box register used for the transfer of commands between the processing module (PM) of the SIP and CPU. The final six bits are reserved for the SIP address: AD-SIP. The following commands are then contained in register R1:
Direct commands: CIO IPL ##STR2##
This command permits the execution of remote loading and remote starting of the requesting LS by an LS with initialization facilities (pilot system).
CIO buffer allocation to the SIP ##STR3##
This command permits the allocation of a buffer to the SIP, thus authorizing the communication of an incoming request to the LS.
CIO mode ##STR4##
This command causes the SIP to make the transition from an initialization to an operational mode, thus inhibiting certain external operations which might perturb the local system (e.g. the simulation of orders sent to the control panel).
Indirect commands ##STR5##
This command allows the communication of the address of a block located in the main store containing the information relating to a command or a result to the SIP.
SST (READ STATUS) ##STR6##
During the execution of the instruction, the content of the data bus is loaded into the register specified by field R1. The condition register (CR) is defined as follows:
00--instruction accepted (state WST)
01--instruction refused (state WST)
11--address not recognized.
The contents of the register specified by R1 is then either directly an incoming request, or the address in the main store of an incoming request or result block.
SST direct
SST ACK ##STR7##
This response means that the last indirect command has been stored by the SIP and thus possibly that the buffer used to communicate it is once more available for the system.
SST releasing of store in SIP ##STR8##
This response means that, following the exceeding of the storage capacity of the SIP, there is once more space available to receive commands or results.
SST command unknown ##STR9##
This response means that the command sent by the LS is unknown to the SIP, which has been unable to interpret it.
SST indirect ##STR10##
In this case, the register specified by R1 contains the address in the main store of an incoming request or result block.
The SIP is provided with a mechanism permitting direct access to the main store 16 of the IS, allowing it to transfer information directly from its I/O (input/output) buffers into the main store and from the latter to its I/O buffers. This mechanism will be described later.
INTERACTION BETWEEN LOCAL SYSTEMS
FIG. 2 is a flow chart describing in a general manner the chaining of transactions between two local systems connected to the communications network.
FIG. 2 is generally divided into four flow columns, from left to right relating to the origin local system, the origin system intercommunications processor, the destination intercommunications processor, and the destination local system. When the LS origin wishes to communicate with an LS destination, a service request (100) is made and analyzed by LS (101), and the command block to be executed by the LS destination is constructed, (102). The CPU origin sends an indirect instruction CIO START to the SIP origin, signalling to it (synchronization) that it is being sent a command, resulting in the transfer of the command block to the SIP (the address of the block in the main store being specified), in (103) and (104). The SIP awaits the end of the execution of the transfer of the command block WAIT ACK (105). On receiving an interrupt from the SIP, the CPU executes an SST (105a). If the contents of R1 are zero, (105b), the LS awaits the result of the execution of the command AWAIT RESULT (124). Otherwise, the LS (R1 not zero) awaits the acknowledgment (105).
The command block is preprocessed by the SIP origin (106) and then a request is sent to the selected SIP destination after its localization via the CM and the communications network. This request is preprocessed by the SIP destination (108), which sends an interrupt (IT) to the LS destination. The CPU destination, which was in the await incoming request state (109), (relative to the SIP origin in question) executes an SST to identify the reason for the interruption, (110). If the latter, (111), is not an incoming request, the system returns to (109). If the reason for the interrupt is a request, the command block is processed (112), a result block is constructed (113), and the SIP destination is informed by an indirect CIO (114), while the CPU awaits the acceptance (AWAIT ACK) of the SIP destination (115). The SIP destination, which was in the state AWAIT Result (116) receives the block of results (117) and sends an interrupt (IT) at the end of the transfer to the CPU destination, which executes an instruction SST (118). The SIP destination, which sends the results (119) to the SIP origin, via a request on the communications network, awaits the instruction SST (AWAIT SST) (120) before switching to the state END. The CPU destination also switches to the state END (120A) on the acknowledgment SST, (121) (ACK).
The SIP origin which was in the state (AWAIT Result) (122), after loading the result into main memory of the LS origin (122a), sends an interrupt IT to the CPU origin and awaits SST, (123). The CPU origin, which was in the state (AWAIT Result) (124), then executes an instruction SST (125) which causes the SIP origin to switch to the state END (123A) and itself analyzes the results which are loaded in its main store (references 126 and 127) and then switched to the state END (127A).
Exchange mechanisms with the communications network via the Communication Module CM
The SIP uses its input/output buffers (256 words) to communicate with the communications network via the CM by means of an interface SIP/CM defined in the Appendix. An I/O buffer contains the instructions, parameters and when applicable the data to be transmitted. The CM is capable of interpreting the command received and of executing it. After execution, the CM loads a status word concerning the execution into the I/O buffer which contained the command. The CM has direct access to the I/O buffers allocated to it. A buffer is allocated to the CM by the issue of an I/O instruction (write) to it. The contents of the bus then specify the address of the SIP buffer to be processed and its nature. The SIP receives an end of execution signal by the transmission of an interrupt from the CM. The SIP can then recognize the address of the buffer containing the result by executing an I/O instruction (read). Two output and two input buffers may be allocated to the CM simultaneously. This permits bidirectional transfers, processing a block of each type (input and output) simultaneously and chaining the stand-by buffer at the end of execution of the current buffers. The input/output buffers may be located throughout the addressable storage space accessible to the SIP/CM bus (64 kwords).
Format of the Relevant 16-bit Instructions:
Input/output instructions used
WRITE COMMAND
This instruction is used to synchronize the communication module (CM) for the execution of a command specified in the associated I/O buffer. A distinction may be made between four different commands:
1. Connection of an LS to the communications network. In this case parameters concerning the intended communications are supplied.
2. Disconnection of LS.
3. Data emission. This is reflected in a request for the issue of a data block (<64 kwords), specifying emission parameters.
4. Data reception. This is reflected in the provision of an empty block (<64 kwords) used to store incoming data.
Information present on the SIP/CM bus during the execution of this insturction:
Bus addresses (SIP→CM) ##STR11## CM1 to CM6 specify the address of the CM CD1, CD2 specify the nature of the command defined below. ##STR12## During a direct command the data bus specifies the command. In other cases, the data bus contains the address of the buffer containing the command to be executed.
Definition of the data bus during a direct command CD2, CD1=1 0.
→data bus ##STR13## GPC=send a general purpose command to the defined destination.
This command is interpreted by the CM and may be used for various purposes. ##STR14## D1=0 connection of the defined source D1=1 disconnection of the defined source. ##STR15## General disconnection from the communication network (e.g. the LS is isolated).
READ STATUS (SST)
This instruction is used to synchronize the SIP after the execution by the CM of a command sent to it. On receipt of an interrupt from the CM, the SIP executes a Read Status instruction and thus recovers the address of the buffer executed.
Information on the SIP/CM bus during the execution of this instruction:
Bus addresses (SIP→CM) ##STR16## CM1 to CM6 specify the CM address.
Data bus (CM→SIP) ##STR17##
SIP connection block to the communications network ##STR18## The block is defined in the following way: PSI: packet size
TTV: value of emission watch dog timer
MNN: indicates the maximum permissible number of RNR during which a source station will repeat its call after receipt. This counter makes it possible to detect a continuous and abnormal busy state of a called station. RNR is a signal indicating that the destination (receiver) is not ready to accept a transmission.
MORYN: maximum number of retries in output mode.
RTV: value of the reception watch dog timer
MIRYN: maximum number of retries in input mode.
For the broadcast mode, the LS number defines the connected or disconnected LS, where the maximum possible number of connections is 64. The least significant bit defines whether or not there is a connection.
θ R =RTV.FD indicates the maximum permissible time interval between the issue of two successive words by an LS origin. This timer makes it possible to detect a fault in the emitting LS.
θ E =TTV.FD indicates the maximum time interval at the end of which all connected LS should have replied to a call (ASK). This timer makes it possible to detect a fault in the called LS on an addressed call and initiates the issue of data on a broadcast call (synchronization). FD is a base timer located in the CM producing a base time interval.
The connection mode makes it possible to define limited groups of users (applications) and to inhibit the broadcast mode for local systems without filter mechanisms (SIP) as determined by the local resources.
In order to modify the connection parameters in the connections block it is necessary to execute a disconnection before making a reconnection specifying new parameter values. The SIP may transmit after a connection.
Definition of the transmission block ##STR19## W: await RNR in broadcast mode If W=0, transmit the message to the ready LS's on receipt of the first RNR.
If W=1, on receipt of an RNR wait and retry the call.
B=1 broadcast mode
B=0 addressed mode.
In addressed mode, the destination address specifies the LS destination. In broadcast mode, if Address Dest.=0, the message is intended for all destinations; otherwise, the specified address corresponds to a group of destinations. C2, C1 specify the position of the block in the message as described below. ##STR20##
The communication priority level (8 bits) is used in the event of conflicts (the highest priority is selected).
After a transmission, a block is constructed to define the result of the transmission.
Definition of the result block ##STR21##
The result of the transmission is loaded into TSW (word 1) of the transmission block.
S1=1 network not operational
S2=1 called LS abnormally occupied
S3=1 transmission fault on the network.
The number of the LS causing the problem in broadcast mode is also loaded into TSW.
RODBL defines the length of the data block still to be transferred (loaded in word 2) in the event of a fault.
RODBA defines the address of the data block to be transferred in the event of a fault (loaded in word 3).
After a connection is terminated, an LS may receive a transmission from another LS either in reply to a request or because a particular LS has something to send.
Definition of a reception block ##STR22## RSW: reception status word, initially zero
Definition of the result of a reception block ##STR23##
The result is loaded into the RSW (word 1).
S 1 =1 network not operational
S 2 =1 transmission error (loss of message coherence)
S 3 =1 reception fault on the network.
In the event of a fault, the address of the source is loaded. Words 2 and 3 in the reception block are kept unaltered. The data per packet are loaded into the space allocated to the CM. The significance of C 2 C 1 has been defined earlier. Several packets may be received, each defined by its length and its source address. At the end of a packet, an all zero word signals the end of reception.
The command will implicitly be regarded as having been executed if:
a. the input buffer is full;
b. if another buffer is allocated at the end of reception of the current packet;
c. on receipt of an end of text (ETX);
d. on detection of a fault.
FIG. 3 is a flow chart describing the general enchaining of communications between the SIP (left column) and the CM (right column). The precise and fine grained structure of the exchange itself will be described later. After the construction of command block 130, the buffer is allocated to the CM by the SIP origin 131. Communication with the CM is established via an I/O command WRITE 132 and the command block is transferred to the CM. The CM, which is in the WAIT state 133, switches to execution state (execution of the command block 134). This implies that the command block is analyzed and executed. The CM then sends an interrupt (IT) to the SIP which is awaiting the result 135. The SIP responds to the IT by the I/O instruction READ which reads out the word from the result of the CM 136. The CM awaiting this command 137 switches to the END state (137A).
The SIP allocates the buffer to its processing module (PM) 138, analyzes the result 139 and switches to the END state (139A).
DESCRIPTION OF THE SYSTEM INTERCOMMUNICATIONS PROCESSOR
FIG. 4 is a block diagram of the SIP showing the main components with their connections. The SIP can be partitioned into four modules providing its respective processing and communication functions. The four modules are the processing module (PM) 20, the local communication module (LCM) 21, the communication interface module (CMI) 22 and the data buffer management module (DBMM) 23. The PM, LCM and CMI operate in parallel, whereas the DBMM is used for communication between them. The main interconnections between the four SIP modules are shown, i.e. the address, data and control lines. The physical interfaces between the SIP and a local system 10 based upon a central processing unit of the Philips P800 serie and between the SIP and the communications network 14 via the CM 13 are described in the Appendix. The use of the principal interface and control signals will be described in detail hereinafter.
The interconnections between the four modules of the SIP (the internal bus) consist of the same address (16 lines) and data (16 lines) lines as for the external interfaces. Address lines are designated by a crossing sign therethrough.
The PM 20 consists of a microcomputer comprising mainly an INTEL 8086 microprocessor (24) with 64 kwords of read/write store (RAM) (random access memory) 25, and 2 kwords of reprogrammable read only memory (PROM) 26. The PM control automat CA is represented by 27. This mechanism (CA) 27 consists of a wired logic system (PROM) connected to an FPLA (field programmable logic array). The contents of the FPLA define the sequencing executed by the CA 27 as a function of the various possible states. The CA 27 will be described in detail. An interrupt and priority control system is shown by 28 and a system of two timers by 29. A clock system 30 provides the clock signals used in the SIP 11. The PM 20 performs the coordination, control and initialization functions already described.
The LCM 21 provides the communications with a P 800 LS 10, i.e. with the CPU 15, via I/O instructions and the interrupt mechanism, and with the main store 16 via direct memory access (DMA). In addition, the LCM 21 simulates commands from the control panel (PAN.SIM. in FIG. 4). The LCM 21 consists of a microprogrammed control automat 31, and interface and control circuits symbolically represented by 32 to 37. These include the interface circuits 32 and 33 to ensure compatibility (logic level, power, etc.) between the LCM and an LS. The circuits controlling the bus and decoding the instructions are indicated by 34. Counter 38 defines the direct access memory address of the main store 16 (DMA) and counter 39 defines the address of the buffer of the DBMM 23. Logic gates 35 control transfer of the address received from the LS and multiplexer 37 selects the input when a simulation is executed via the control panel.
The CMI 22 controls the interface with the CM 13 either via a processor interface or via a store interface, depending upon the initialized transfers (the interface is described in the Appendix). The CMI consists of a microprogrammed control automat 40 and circuits symbolically represented by 41 to 48. The logic gates 46 to 48 are interface circuits. Registers 41 and 42 define the address of the command and result block transferred between CMI 22 and CM 13 and register 44 is used as a mail box register for the address of CM 13. Comparator 43 compares the address of the buffer allocated to the CM at the end of the execution of the command with the address sent by the CM, thus the PM is informed that the buffer is to be released. Comparator 45 compares the address of the SIP buffer with the address sent by the CM.
The DBMM 23 consists of two I/O buffers with triple access represented by 50 and 51. These will be explained in more detail with respect to FIG. 7. Furthermore, there is provided a bidirectional allocation mechanism between:
the PM and the P 800 LS (via the LCM),
the PM and the CM (via the CMI),
the P 800 LS and the CM (via the LCM and CMI).
The buffer allocation mechanism is located in the DBMM microprogrammed control automat 49, which in its turn is initiated by the PM. The system of multiplexers 52 and 53 provide the appropriate access under the control of CA 49, while the interface circuits with the CM are symbolically represented by 54.
FIG. 5 is a functional diagram showing the components of PM 20 already described with respect to FIG. 4 and their connections to the internal bus (data and address control) needed to describe their operation within the context of the invention. Dynamic RAM 25 with a capacity of 64 kwords contains the coordination executive (CCE) and the tables describing the objects and resources of the LS. This dynamic memory is refreshed between input/output transmissions via a refreshment module 58 connected to the control and address bus controlled by CA 27. The 2 kword PROM 26 contains the processes for the initialization, remote loading and remote starting of the system. The programs contained in stores 25 and 26 are executed by microprocessor 24.
Timers 29 comprise two counters which may be programmed in time by microprocessor 24 and are used to verify that an expected event has indeed taken place within a given time interval. If this allotted time is exceeded, a fault is signalled which initiates recovery of information procedures.
Microprocessor 24 operates in interrupt mode and will thus be informed by means of the interrupt and priority control system 28 when certain events occur. In decreasing order of priority, these events are:
IPWF: (Power Supply Interrupt Fault)
This interrupt, which cannot be masked, is directly received by the microprocessor 24 when a failure in an LS power supply is detected. A power reserve of the order of a few milliseconds allows the PM to perform a context safeguard procedure helping to provide a reconfiguration of the total system, if necessary, once restarted.
TIME 2; TIME 3
These interrupts indicate that the time interval programmed in timer 1 (TIME 1) or 2 (TIME 2) has been reached.
IRTC
This interrupt is initiated by the LS real time clock. Microprocessor 24 may then broadcast this to all the LS in order to synchronize them.
CMI T 1 ; CMI T 2
These two interrupts indicate that the appropriate I/O buffers (50 and 51) are available and contain a result concerning the execution of the transmitted command.
PCCST 3
This interrupt shows that a mail box register (60) providing communication between the LCM and the PM contains a command from the LS addressed to the PM.
LCEOE
This interrupt indicates that the transfer of information requested by the PM from the LCM has terminated and the associated I/O buffer (50 or 51) is once more available to the PM.
IMBE
This interrupt indicates that mail box register 42 providing communication between the CMI and the PM is cleared and may be used to send a new command to the CM.
FIG. 6 shows the state sequences of the PM control automat 27. The possible states are:
T 1 : Idle State
T 2 : presentation of the addresses on the bus
T3M and T3P: presentation of the data concerning the store (RAM) and the peripherals respectively
T 4 : refreshment of dynamic RAM 25.
When microprocessor 24 is not using the internal bus, the state sequencer alternates between T1 and T4 and a complete row of the RAM is renewed during state T4. Refreshment module 58 contains a counter which carries out the operation +1 on the address of the RAM every time that a row is refreshed. Either the bus address or the address defined by the refreshment counter is selected by means of a multiplexer. Where microprocessor 24 is using the bus, a row is refreshed when use of the bus is completed (T4).
TW: is the delay needed to provide the minimum access time specified by the I/O buffers (50 and 51) and to guarantee the minimum cycle time specified for the dynamic RAM when a microprocessor access directly follows a renewal cycle.
The signals conditioning the switching of the state sequencer are:
CLKN: system clock. At each activation of this signal (active, negative), the state sequencer switches to another state.
MCL: signal resetting the state sequencer to the initial state (T1).
MALE: signal activated at the start of a bus cycle.
After an MCL (Master clear), the state sequencer is in state T1. In the absence of a bus cycle (MALE), the state sequencer switches between T1 and T4, controlled by the logic condition (CLKN.MALE). If a bus cycle (MALE) is detected during T1 or T4, the sequencer switches to T2 (CLKN.MALE). If the bus cycle is a peripheral or PROM access, the sequencer switches to T3P, specified by the logic condition CLKN (PROM+PER) switching to T4 on the next CKLN. If the bus cycle is a RAM access, the sequencer switches to T3M (logic condition CLKN.RAM) followed by TW and T4.
The stores and peripherals are selected by decoding the address bits and certain command bits in the PM. Table I below specifies the decoding and selections.
TABLE I__________________________________________________________________________MI0 A19M A17M A15M A14M A13M A12M A11M A10M A9M Selection__________________________________________________________________________0 X X 0 0 0 0 0 0 0 Selection of the CM (1)0 X X 0 0 0 1 0 0 0 Selection of LCM0 X X 0 0 1 0 0 0 0 allocation of buffer No 1 to the PM0 X X 0 0 1 0 0 0 1 allocation of buffer No 2 to the PM0 X X 0 0 1 0 0 1 0 allocation of buffer No 1 to the CM0 X X 0 0 1 0 0 1 1 allocation of buffer No 2 to the CM0 X X 0 0 1 0 1 0 0 allocation of buffer No 1 to the LCM0 X X 0 0 1 0 1 0 1 allocation of buffer No 2 to the LCM0 X X 0 0 1 1 1 1 0 RAZ IRTC Real-time clock (2)0 X X 0 1 0 0 0 0 0 timer initi- alization (3)0 X X 1 0 0 0 0 0 0 initializa- tion system IT (4)1 0 0 0 most significant address selection bits RAM 64 K (5)1 0 1 0 0 0 0 0 0 0 selection buffer No 1 (5)1 0 1 0 0 0 0 0 0 1 selection buffer No 2 (5)1 1 1 1 1 1 1 most selection significant PROM (5)__________________________________________________________________________
The bit MIO defines the type of store access to the peripheral. The following notes (1)-(5) are explained:
In Table I
(1) The address bits A1M to A8M specify the address of the CM concerned and the nature of the command.
(2) The real-time clock interrupt (IRTC) is reset to zero.
(3) The address bits A1M, A2M specify the number of the initialized timer.
(4) I1M specifies the command word sent.
(5) A1M to A8M indicate the least significant address bits of the store.
The bits marked "X" do not matter.
The internal communication mechanism of the SIP and the I/O buffers of the DBMM will now be described. The location of the SIP between an LS and the communications network means that the SIP has to manage a great deal of information passing through it. This information follows various paths depending upon its nature and origin. A distinction must be made between:
the commands to the SIP issued by the LS and received by the PM of the SIP which preprocesses them;
the outgoing requests emitted by the PM to the communications network;
the incoming requests received from the communications network and sent to the PM for analysis. After analysis, these requests may be communicated to the LS by the PM.
the data emitted by an LS to the communications network;
the data received from the communications network and sent to the LS.
The communications network, which makes possible a continuous bidirectional traffic of 300 kwords per second, also implies rapid transfers through the SIP. Outside the PM processing time, it is therefore important for the transit time of the information through the SIP to be as rapid as possible.
To attain this objective, the invention makes use of the following facilities:
use of the modules (LCM, CMI) controlled by the PM and working in parallel with it;
use of a communication mechanism facilitating the exchanges between the three components under consideration, (LS, PM, communications network via the CM).
The communication mechanism comprises the two I/O buffers 50 and 51 (each of which are 256 word RAM) with triple access, and an allocation mechanism associated with each of them. FIG. 7 shows the principle of this mechanism for a buffer (e.g. 50). In FIG. 7, buffer 50 may be independently allocated to one of the three components concerned (PM, LS, CM) via the PM bus, the LS bus or the CM bus and multiplexer 52 in FIG. 2, which consists of selectable gates 52a, 52b and 52c shown in FIG. 7. The allocation control is carried out by the PM itself and the allocation mechanism 61 is a wired logic mechanism contained in CA 49 of the DBMM. A module (LS, CM) which has been allocated a buffer may use the latter exclusively as long as it has not been restored to the PM. In fact, the use of an I/O buffer by one of the three modules consists in carrying out an information exchange with the LS or with the communications network via the CM.
The allocation mechanism is controlled by the PM by means of the following I/O instructions (reference to Table I):
Allocation of the buffer to the PM;
Allocation of the buffer to the LCM;
Allocation of the buffer to the CM which has direct access to this buffer.
The allocated buffer contains the execution order which is interpreted by the module responsible for processing the requested exchange. The PM is informed of the end of processing via an interrupt (CMIT1, CMIT2, LCEOE); it may then either analyze the information received or use the buffer concerned for another exchange.
FIG. 8 shows the sequencing of the allocation mechanism between the three modules PM, LCM and CM.
The LCM 21 will now be described in detail. This module controls the transfers between the main store 16 of an LS and the I/O buffers 50 and 51 allocated to it. It manages the interface with the CPU 15 and simulates the operator commands of the control panel.
The interface with the CPU 15 is organized on following principles:
1. When a CIO start addressed to the SIP is decoded, there are two possibilities:
a. The LCM is in an exchange state. In this case, the LCM loads the contents of the data bus into the mail box register (60, FIG. 5), transmits an interrupt (PCCST3) to the PM and switches to the execute state. The LCM returns to the exchange state when the PM executes a read mail box register 60 instruction via the selection of the LCM (Table I).
b. The LCM is in an execute state. In this case the LCM rejects the CIO start (CR=1).
2. On the decoding of an SST addressed to the SIP, there are also two possibilities:
a. The LCM is not ready to provide a status word to the LS (WST), the SST is thus rejected (CR=1)
b. The LCM is ready to communicate a status word to the LS via an interrupt (WST); thus, when the instruction SST is decoded, it is accepted and the status word is sent on the data bus.
The CA 31 of the LCM controls the switching between the states needed to control the CPU/LCM interface and the latter are shown in detail in FIG. 9. The possible states are:
IDLE 1, IDLE 2: entered via the signals TMP or LCMSN.
CAC1: CIO start accepted and entered via signal CIO.
CACN1, CACN2: CIO start rejected and entered by the signals CIO.LCMSN or CIO.CLMSN.
SAC1, SAC2, SAC3, SAC4: SST analyzed and entered via the signals SST.WST or LCMSN or UNCOND.
SACN1, SACN2: SST rejected and entered via the condition SS.WST.
ARE1, ARE2: address recognized and entered via the condition TMP.ARE.
AREN 1, AREN2: address not recognized and entered via the condition TMP.ARE.
The signals or (active) logic conditions needed for switching between states are defined below.
LCMSN: read-out of the mail box register by the PM.
LCMSN: no read-out of the mail box register by the PM.
ARE: address recognized.
ARE: address not recognized.
AC: command accepted.
UNCOND: unconditional jump.
TMP: synchronization from the CPU.
TPM: synchronization from the SIP.
SST: SST command decoded.
CIO: CIO start command decoded.
WST: LCM ready to provide a status word.
WST: LCM not ready to provide a status word.
TPM/TMP: the generation of TPM (synchronization from the SIP) automatically causes the generation of TMP which switches the state sequencer into an IDLE state. This serves to synchronize the SIP, and a TMP (synchronization from the CPU) is always necessary for switching into another state.
The LCM is in an IDLE 1 state, i.e. mail box clear. On the receipt of a start CIO (condition TMP.ARE), the LCM switches to the state ARE1 (address recognized) and then to the state CAC1 (CIO accepted) and, on the activation of TMP, to state IDLE 2. When the PM has read out the mail box register (LCMSN), the LCM once more switches to IDLE 1 state (exchange).
If the LCM is in the execute state IDLE2, mail box occupied, the receipt of a CIO start causes it to switch to state ARE2 (address recognized) and then to state CACN2 (CIO not accepted) via condition CIO.LCMSN, The LCM switches to state IDLE on the next TMP. While the LCM is in an execute state, it follows the path IDLE2→ARE2→CACN2→IDLE2. As soon as the LCM switches to an exchange state, the activation of LCMSN allows the LCM to switch to the IDLE state where the next CIO start may be accepted, i.e. the switching path is ARE 2→CACN1 →IDLE2, or ARE2→CACN.LCMSN→CACN1→IDLE1.
Likewise, if the LCM is in the state IDLE1 and if it is ready to provide a status word, the SST decoding path will be IDLE1→ARE1→SAC1→SAC3→IDLE1. If the LCM is not ready to provide a status word, the path followed will be IDLE1→ARE1→SACN1→IDLE1.
If the LCM is in the state IDLE2, there are also two possibilities. Where the LCM is ready to provide a status word, the path will be IDLE2→ARE2→SAC2→SAC4→IDLE2, or IDLE2→ARE2→SAC2→SAC4→SAC3→IDLE1, or IDLE2→ARE2→SAC2→SAC1→SAC3→IDLE1. If the LCM is not ready to provide a status word, the path followed will be IDLE2→ARE2→SACN3→IDLE2, or IDLE2→ARE2→SACN3→SACN1→IDLE1. The various possibilities take into account the fact that the LCM may switch between the execute and exchange states (the dotted line separates FIG. 9 into two parts, that where the CIO start is accepted and that where it is rejected). In addition, due to synchronization problems, the LCM must switch via intermediate and different states, e.g. the activation of LCMSN or LCMSN.
Where the address is not recognized (ARE), the LCM will alternate between IDLE1 and AREN1 or IDLE2 and AREN2, successively, depending upon the particular case.
The simulation of an operator command from the control panel is carried out by the allocation of a command block located in an I/O buffer (described later with reference to FIG. 10). The format of a simulation command block is defined below. ##STR24## Word 1 contains 2 bits defining a simulation command (OO). Word 2 contains the bits defining each command to be simulated.
Bit MCN: Master Clear (no parameter)
Bit INT: control pannel interrupt (no parameter)
Bit INST: execution of a program instruction by instruction (no parameter)
IPL: initial loading program (parameters on control panel keys)
RUN: start of a program (no parameter)
LR: load a register, number specified in REP (4 bits) (content parameters to be loaded)
HALT: halt the CPU
X: not used in this particular context.
The commands can therefore be simulated by program via the I/O buffers, or directly by the control panel via multiplexer 37 (FIGS. 4 and 10). The interpretation of these controls by the CPU is performed by a module located within it.
The exchange of information blocks between the SIP and the LS by direct access to the store will now be described. The exchange of information blocks is explicitly requested by the PM from the LCM when an I/O buffer is allocated to it. This buffer then contains the directives concerning the requested exchange. The format of a command block is defined below. ##STR25## Bit IT: issue of an interrupt to the CPU as soon as the transfer operation has been carried out (IT=1). Here, the status word is transferred on the bus when the SST is executed by the CPU.
MAD 128, MAD 64: two most significant bits defining the address of 128 kwords.
Bit S: indicates the direction of exchange.
The exchange mechanism with the LS is described with reference to FIG. 10 (structural diagram of the LCM) and FIG. 11 (detailed flowchart of the microprogram controlling the exchange mechanism with the LS). This microprogram, shown in FIG. 12, which is stored in CA 31 of the LCM, is a typical example of the various microprograms used in this invention.
Initially, CA 31 of the LCM is in the IDLE state shown by micro-instruction 1 (uI1) awaiting the allocation of an I/O buffer (50 or 51) intended for it. As soon as LCRS=1 (test 80, to determine whether the buffer is allocated to the LCM), the first two words of the buffer (command block) are loaded into register MAR (memory address register) 38 of the LCM (group from uI2 to 8). The loading path of register MAR 38 is via logic gates 71 controlled by the micro-commands (uc) of the DBMM. The lefthand bit of the buffer is then tested (test 81). If SIM=0 (simulation command), the command to be simulated in MAR 38 is sent to CPU 15 (uI 27). If SIM=1, counters MAR 38, BAR 39 (buffer address register) and BLR 72 (block length register) are loaded with the exchange parameters contained in words 3 and 4 of the command block (uI 9 to 12). The loading path is via gates 71 for MAR, BLR and BAR, and via gates 73 for addressing the I/O buffer, under the micro control of the appropriate control automats of the LCM and DBMM.
The exchange may then begin. A request is made for the SIP/LS bus (uI 13 and 14 and test 83). As soon as the bus has been obtained (active CEACK in test 84), the transfer of a word is carried out (uI 15 to 19 if the direction of transfer is from the buffer to main store 16, and uI 20 to 26 if it is the other way round). Test 85 defines the transfer direction. The operation -1 is carried out on BLR, +1 on BAR and +2 on MAR. Next a test 82 is made on LREQZ to determine the state of BLR. If BLR≠0, the word transfer sequence begins again.
If BLR=0, bit IT is tested (test 86). If IT=0 an interrupt is sent to the PM (uI 30) indicating that the command is terminated. The LCM switches to the IDLE state when the PM has de-allocated the buffer to the LCM (LCRS=0 in test 87).
If, in test 86, IT=1, an interrupt is sent to CPU 15 (uI 28) and the I/O instruction SST is awaited (test 88). On its receipt, the status word is put on to the bus (uI 29). At the end of the exchange (PCES=0 in test 89 if the state word is accepted by the CPU) an interrupt is sent to the PM (uI 30), the I/O buffer is de-allocated and a return is made to IDLE.
Where a command is simulated (uI 27), a monostable multivibrator is triggered at the start of the simulation and reset at the end. The state of the monostable multivibrator is tested in test 90 and if it is zero an interrupt is sent to the PM as already described. Tests 91 and 92 are made in the word transfer sequences pending the loading signals TRMS. and TRSMST respectively.
In FIG. 10, 32 and 33 are bidirectional interface circuits which store the data during an exchange, while 37 is a multiplexer which selects either the command from the I/O buffer via MAR 38 or those from the control panel (PAN SIM) under control of control automat 31.
The microprogram for this sequencer is described in detail in FIG. 12 and the exact description of each microinstruction bit is given below.
NONE: -1 (decrement) on the length of the block to be transferred
EOCE: clearing of the P 800 bus (LS) by the LCM
PONE: +1 (increment) on the address of the I/O buffer
LCEOE: interrupt to the PM indicating the end of the execution of a command
LCW: READ/WRITE on the I/O buffer
BIOEN: BIO (Bus in/out data) activated
CEREQ: request for P 800 bus by the LCM
MARL 1N: loading of register MAR (right-hand part)
MARL 2N: loading of register MAR (left-hand part)
MADVAL: main store address→bus (valid)
BIOVAL: data→bus (valid)
PTWO: +2 (double increment) on the address of the main store
TMR: synchronization sent to the main store
WST: wait state (interrupt to the CPU at the end of an exchange)
RIT: reset to zero of interrupt on receipt of SST
LCSA: synchronization of an operation on the I/O buffer
WLCF: loading of the mail box of the PM (LCM→PM)
BALRLN: loading of registers BAR, BLR
SIME: simulation.
CMI 22 is responsible for controlling the SIP access to the interface with the communications network via CM 13, sending the CM the commands loaded by the PM into a mail box register of the CMI (42) and loading the results from the CM into the mail box register (41) of the PM before alerting the mail via an interrupt.
The exchange mechanism is described with reference to FIG. 13 (structural diagram of the CMI) and FIG. 14 (state sequences of the CMI control automat). There are two possibilities:
1. Command word sent to the CM from the PM
As soon as a command word is placed in the mail box register (BLCMI) 42 by the PM, the control automat 40 switches to state E1 (BUS REQ) from state E0 (IDLE) in which an ICM/CM interface request is initialized. On receipt of a signal indicating that the interface has been allocated to the ICM (BUS AL.), the latter switches to state E4 (ECH OUT) and transmits the command WRITE after having put the address of the CM on the address bus and the contents of (ICM LB) 42 on the data bus. On detection of an end of exchange (signal EOE), control automat 40 issues an interrupt (IMBE) to the PM specifying that the CMI mail box register is once more available for communication of another command and at the same time switches to state E5 (ALERT PM). The control automat returns to state E0 (IDLE) as soon as the PM executes an I/O instruction (READ) which is interpreted by the ICM as an acknowledgment of the interrupt (PM.OK).
2. Result word from the CM to the PM
As soon as an interrupt from the CM is received by the CMI control automat, the CMI switches from state 1 (IDLE) to state E0 (BUS REQ) in which a bus request is initialized. On the receipt of a signal indicating that the bus has been allocated to the ICM (BUS AL.), the latter switches to state E2 (ECH IN) and issues the command READ after having put the address of the CM on the address bus. On detection of an end of exchange and after the result word has been loaded into the mail box register of the PM (41), the control automat 40 switches to state E3 (ALERT PM) and issues an interrupt CMI T1 (or CMI T2) to the PM. As soon as the PM has read out its mail box by executing an I/O instruction (READ), the control automat 40 switches to state E1 (IDLE). The conditions needed for switching between states are shown in FIG. 14.
The initialization functions, which include the procedures of initialization, remote loading and remote starting are described with reference to the flow chart of FIG. 15. These procedures are stored in the PROM store (2 kwords) of the SIP.
The LS may be of different types.
A tributary LS has no automatic starting and loading capacities and must be remote-loaded and remote-started.
A pilot LS has self-loading, self-triggering capacities (hardware and software) and may remotely load and start tributary LS.
An initial LS is used by the operator responsible for the starting and initialization of the global distributed data processing system. This may be a pilot LS or tributary LS.
The initial LS is started by the operator, and the local SIP and its peripherals are initialized by the master clear (MCL) of the system, ref. 170 in flow chart 15. The SIP of the initial LS initialized the local CM ref. 171 before locally simulating the IPL (initial program loader) ref. 173. The initial SIP waits for a time θ1 before simulating the IPL to allow the LS time stabilize, particularly the disc units, ref. 172.
If the initial LS is a tributary LS it sends a start CIO IPL to the tributary SIP (control panel keys set to the address of the SIP) refs. 174 and 175. The local (tributary) SIP on receipt of a CIO IPL issues a command to supply power to all the LS (execution by the local CM which is powered) and waits for a global system stabilization time θ1, refs. 176 and 177. As soon as the whole of the system has stabilized, the SIP broadcasts a request for the remote loading and remote starting of the main store of its LS (16 on FIG. 1) and of the RAM (25 on FIG. 4) of the SIP itself, ref. 178. On receipt of this broadcast request, the pilot LS which are capable of remotely loading the tributary LS concerned respond positively, ref. 180. The tributary LS then issues a remote loading command to a selected pilot LS ref. 181 which undertakes the initialization of the tributary LS.
If the local LS is a pilot LS ref. 182, on the simulation of IPL by its SIP, the initial program is loaded locally (the keys of the control panel indicating the peripheral used for loading) ref. 183, and then an initialization module capable of remotely loading the tributary LS and self-loading the local LS (pilot here) is activated, ref. 184. The numbers of the LS which can be remotely loaded by each pilot LS are given to the local SIP which, on receipt of incoming requests which can be satisfied by the local pilot LS, responds positively to the tributary LS concerned. Where the initial LS is a pilot LS, the SIP issues a power on command to all, ref. 179.
The tributary LS then sends a command for remote loading to the selected pilot LS (the first positive reply received from a pilot LS is selected) ref. 181, and the SIP proceeds with the remote loading and starting of the tributary LS via a request for remote loading and triggering to its pilot LS ref. 186, followed by the execution of this order, ref. 188, which awaits the loading of the pilot SIP, ref. 187. This command consists in executing in the tributary LS the remote loading of system and user programs into the main store, the simulation of LR, LCM, RUN on the control panel of the P 800, the remote loading of the coordination execution in the RAM of the tributary SIP and the branching to the start address of this program of the SIP, this being shown by ref. 189. At the end of execution, the tributary SIP and LS switch to an operational state, ref. 190 and 191.
When the pilot LS has loaded or is sure that another pilot LS's loaded all the tributary LS which it can load remotely (via the last incoming request test, ref. 192) it initializes itself, ref. 193. This consists in loading the RAM of its own SIP, starting the SIP at the level of the RAM, loading its own P 800 system and starting it. At the end of this sequence, the pilot LS and SIP switch to an operational state, ref. 194 and 195.
DESCRIPTON OF THE COORDINATION FUNCTIONS
The operation of the various elements of the SIP and the communication mechanisms with its own LS and the others located on the communications network via the CM have already been described. What now remains is therefore to describe explicitly the coordination functions allocated to the coordination layer, i.e. the SIP.
The coordination layer, i.e. the SIP, performs the following actions on the commands from an LS via its operating system.
Initialization of the entire system (already described).
Allocation of the resources according to availability and local load.
Communications between processes belonging to different users applications.
Translation of address and coding parameters between the global and local levels.
Detection of faults in the system.
Protection of applications by monitoring the rights of access to the resources and object at the level of each LS.
Three types of command are sent from the local system to the coordination layer by the communication mechanisms already described (connection, transmission reception block, etc.). They are the commands, messages and service requests.
Commands are sent either in the addressed mode or in the broadcast mode and are directly executed by the LS and SIP concerned. These may be used to initialize the overall system and also during reconfiguration or maintenance, i.e. when the system does not yet have or no longer has the capacity to process other orders.
Messages sent to a mail box (logical addressing) allow processes belonging to respective different user applications to communicate.
Service requests are sent by active processes which wish to acquire a resource.
The receipt of these three types of orders implies the initilization of a micro-transaction consisting of several steps concerning the processing of the order. A micro-transaction is set up as soon as a command, a message or a request is received and is destroyed once the order has finally and completely been performed. Micro-transactions are transferred between LS by the communication mechanisms previously described.
The steps make it possible to synchronize the various LS concerned and provide starting points in the event of reconfiguration. Every micro-transaction consists of a two-word header, followed by information constructed in relation to the nature of the order, as shown below. ##STR26##
In this invention, only the commands may be directly addressed to an LS. The other orders always comprise at least one step during which the information is broadcast to an LS sub-assembly or to all of them.
The execution of the orders received from outside the LS is described below. ##STR27## A command is always executed by the LS units addressed.
The messages are directly loaded into the specified mail boxes if the size of the message sent will fit into the available space in the mail box. A distinction should be made between the mail boxes used in the format of an order and those of the SIP. The latter represent a physical space (usually a register) allowing the various components of the SIP and in the CM to intercommunicate, while the former represent a logical space or logical address referenced by its name (associative reference). The name of the mail box (LB), for example, indicated in a message describes a logical space referenced by its special name in the RAM store of the SIP. ##STR28##
The orders may, for instance, define the opening, closing, reading or writing of the LB by creating processes.
The reading of a mail box by the destination process is carried out during its initial execution or by positioning an event bit if the process is being executed.
N steps may be distinguished in the microtransaction where N>1; an example is given below. ##STR29##
When a complete message is arranged in a mail box, an event is broadcast so as to inform the creator process that a message is available for it. If this process is being executed, it can then program a read-out of the mail box. The execution order and the event are sent in broadcast mode to locate the mail box and the creator process in the SIP concerned. The format is defined below. ##STR30## The three-bit code indicates the nature of the descriptive block. There are eight possible types.
If the address of the next link=0, the present block is the last.
In the case of a message, therefore, the destination SIP carry out a filtering process on the mail box name, the size of the message and possibly on the name of the source process.
There are two possible types of service requests. All the resources defined by the source process are concerned, e.g. the updating of multiple copies of data bases. The mechanism used is similar to that used for the mail boxes, i.e. an execution order is directly broadcast while any data accompanying it are sent as a function of the storage space available at the destinations. The format is defined below: ##STR31##
The detailed processing of a request is described with reference to the flow chart of FIG. 16. This processing corresponds to the SIP pre-processing, source and destination, described in the general flow charts of FIG. 2, refs. 106 and 108. The left hand column refers to the origin SIP, the middle column to destination SIPi, the right hand column to further destination SIPj. When the SIPk (source) receives a service request from a process located in its own LS, it undertakes certain necessary steps, e.g. translation of the parameters (local→global), assembly of the request into a query format and its transmission to all (represented by 200). The SIPk (source) switches to a wait state, ref. 201, this being the selection phase.
This service request is received by all the SIP connected to the overall communications network and, on the receipt of an incoming request, each SIP analyzes the information associated therewith. In the flow chart of FIG. 16, the request is received by the SIPi (destination) and SIPj which are in the wait state, ref. 202 and 203 respectively. The wait state relates only to the service request in question. In this invention, a request issued on the communications network is received by all the SIP's, including the source SIP, i.e. the concept of privilege does not exist. The incoming request is analyzed (refs. 204 and 205) by each SIP with respect to the following:
The definition of the request makes possible an initial screening of the LS which should have the resources to process the request received. For example a compiler is needed for a compilation request, and the telecommunications programs (network and procedure) are needed to process a telecommunication's request.
The application domain name makes possible a second screening giving an equitable distribution of the applications relative to the available resources and thus to the LS, and also makes possible the definition of interactions between these applications (protection and balancing). A table of the application domains known is constructed at the level of each SIP when the overall system is generated (after initialization).
A third screening process may be carried out on the user resource requested by consulting a descriptive table of the local resources (located in the main store of the SIP).
After these three screening processes, each SIP can determine whether its LS has the capacities needed to process the request, refs. 206 and 207. If the result of these analyzes is negative, the SIP switches to the wait state. If the result is positive, another analysis is performed to determine whether these resources are available, refs. 208 and 209. If not, the SIP awaits availability before replying. When all the resources asked for are available (system and user) within an LS, an acknowledgment of receipt is broadcast and all the necessary resources are allocated to the source SIP, while the SIP itself goes into the stand-by state, refs. 210 to 211. A distinction must be made between the system and user resources. For example, a user resource may be the compiler in a request for the compilation of a program, or a central processing unit for the execution of a program. In a telecommunications request, for instance, the programs may be the user resources but the protocols and procedures of the network are the system resources.
The system selects an LS from among those giving a positive reply, one possible selection criterion used being that the first positive reply is selected. The architecture of the system allows only one positive reply to be selected by the source SIP if several SIP give a simultaneous positive reply.
Here, it will be assumed that the two SIP's, SIPi (dest.) and SIPj (dest.) have the required resources and that they are available. SIPi (dest.) and SIPj (dest.) reply positively via a broadcast OK (refs. 210 and 211) but the reply from SIPj (dest.) is received before that from SIPi (dest.) by the SIPi (source). The automatic selection mechanisms ensures that SIPj (dest.) is selected (refs. 212 to 214), one property of the communications network being that a broadcast transmission is received by all at the same time.
Thus the SIPi (dest.) is informed in this broadcast transmission that it has not been selected, the request is annulled (ref. 215) and a return is made to the wait state 202. The SIPk (dest.) selected awaits the execution order from the SIPk (source), ref. 215A.
FIG. 17 shows the automatic selection principle. SIPi, SIPj and SIPk are connected to the communications network. The SIPk issues a request broadcast to all (REQUEST), received by all with a time delay. In the next transmission frame, SIPj, and SIPi reply positively (OKj, OKi) and these replies are received by all, but OKj is received by all before OKi because of its location on the network, and thus every unit is informed of the selection of SIPj. SIPk sends the execution order to SIPj, and SIPi is freed. The execution phase begins (described by refs. 216 to 221) in which the execution order is sent to SIPj, 216, any data sent 217, the translation of the parameters from global to local, the request is loaded into the main store of the LS and an interrupt is sent to the CPU for the execution of the request, 218. The SIPj switches to a wait state 219 and, at the end of the execution of the request 219a sends the data to the SIPk, 220. Then the results are sent to the SIPk, 221 which, in turn, loads them into the main store of its LS and informs it via an interrupt 222. The SIP switches to state END 222A relating to the request concerned.
In general, the SIP source awaits the number of responses specified in the service request issued. When this number is reached, the source SIP terminates the micro-transaction or continues it if the data have to be sent. The number of steps required for the emission of data depends upon the table relative to the data blocks and the temporary store available in the units concerned.
In a second type of service request, a choice of m resources is possible out of n, where n>m. In this case, the first step consists in executing the order received only after automatic selection performed based on the analysis of the replies sent by the various LS capable of processing the request.
The format of this type of request (query and execution) is defined below: ##STR32##
One field in the request word is designed to specify the number of resources requested (m). Each SIP receiving this query analyzes it and decides in the same way as before its capacity to process the incoming request. If the resources requested are available, a positive reply is broadcast and these resources are allocated to the source process of the request. In the query the number of resources required is specified (m). As long as this number is not reached, the SIP, having the necessary capacity and receiving the replies from the others, reply as soon as the resources requested are available. As soon as this number is reached, the SIP which are capable but have not yet replied cancel the request and the source may issue data associated with the request. In the event of simultaneity, the LS's capable of replying positively are selected as already described if the specified number is reached after receipt of their own reply. Otherwise, the request is cancelled and the resources freed. In fact, there is automatic self selection based on the analysis of the request issued and the replies provided by the available SIP.
Each resource is described in an associated 8-word descriptive block (similar to the mail boxes). The format is defined below. ##STR33##
The three-bit code defines the type of resource requested from among eight possibles:
(1) mail box,
(2) logical files,
(3) physical peripherals,
(4) communication line,
(5) queue,
(6) descriptive table of the active processes, The two unused possibilities may be used to specify other resources.
Selection is made by taking the first resources which reply (identical for all).
The replies are sent as soon as the necessary resources are available (system and user).
The processing unit (CPU) is automatically allocated if the source process has a higher priority or the same priority as the procedure being executed. Otherwise the response time is weighted as a function of the load on the processing unit (percentage occupation) as shown on FIG. 18. T max is calculated (programmed in the two timers PM) so as to be a low fraction of the processing time of the service request, but also so as to be significant in view of the normal variations in response time. Thus the use of the resources are optimized by sharing them fairly between the applications.
The translation of the parameters is necessary to allow already developed applications to use the common resources while retaining their local identifiers (file code N o , code line N o , etc.). Translation is thus carried out into local code N o →global code N o by the concatenation of the local code N o to the unit N o .
The translation global code N o →local code H o is carried out using a correspondence table. Certain translations are used to reduce the storage space occupied in the local units. The field name in 6 ASCII characters (global) is transformed into 1 octet (8 bits) at the level of an LS.
The SIP can detect a loss of coherence in a message or the failure of an LS via the CM. The CM can detect the abnormal behaviour of a source or a destination, or the loss of information, and can thus inform the SIP on such detection. The information supplied is:
Loss of information;
Transmission of an impossible message (repeated errors, absence of reply from the destination);
Receipt of an impossible message (repeated errors, absence of reply from the source).
The SIP acts on reaction of one of these items of information from the CM.
A loss of information can be detected because a coherent message is always framed by two control words (STX, ETX). STX indicates start of message and ETX its end. As soon as the CM detects a loss of information (receipt of a packet by a destination whereas said destination has sent a negative acknowledgment of receipt, RNR on a broadcast call), it eliminates all information from the channel concerned until the detection of a new coherent message (STX), implying that the SIP will receive an incomplete message without (ETX). In this case, as soon as the SIP receives a new message from a source (STX) whereas the previous one has not been terminated by (ETX), it cancels the incomplete message and asks for its retransmission from the corresponding source.
When the SIP receives information pertaining to the transmission or reception of an impossible message, it isolates the LS at the origin of the problem by sending a command to the CM to disconnect the LS concerned. On receipt of this command, the CM no longer takes account of the information received in the frames allocated to the specified LS until it has been reconnected.
Appendix__________________________________________________________________________Interface physical SIP/LS P 800 (bus signals)NumberType ofoflineslines Description Mnemonic Source Dest. Function__________________________________________________________________________Control1 accepted ACN SIP CPU I/O dialogControl6 bus interrupt coded lines BIECOO, BIECO5 SIP CPU queriesControl16 I/O lines bus BIOOON, BIO15N TOUS TOUS data channelsControl1 bus occupied BUSYN SIP SIP bus control CPU CPUControl1 character CHA SIP Mem character mode CPU exchangeControl1 request bus BUSRN SIP CPU bus requestControl1 acknowledge CLEARN CPU SIP master clear (MCL)Address18 address lines MADOO, MAD15, SIP Mem addressing MAD64, MAD128 CPU SIPControl1 selected master MSN SIP SIP priority control CPU CPUControl1 input OK OKI CPU CPU selection of SIP SIP next masterControl1 output OK OKO CPU CPU selection of SIP SIP next masterControl1 power supply failure PWF CPU SIP power supply controlControl1 monitor external inter- SCEIN CPU SIP interrupt rupts samplingControl1 monitor priority chain SPYC CPU SIP priority controlControl1 Master clock to TMPN CPU SIP exchange sync. peripheral (CU) signalControl1 master clock to store TMRN CPU Mem. exchange sync. SIP signalControl1 CU clock to master TPMN SIP CPU exchange sync. signalControl1 clock store to master TRMN Mem. SIP exchange sync. CPU signalAddress16 address lines ADRON, ADRFN SIP SIP addressing CM CMControl1 bus sync. BULKN SIP SIP synchronization CMControl1 bus input priority BPRNN SIP of SIP selection of next CM masterControl1 bus output priority BPRON SIP SIP selection of next of CM masterControl1 bus request BREQN SIP bus bus request con- trolControl1 bus occupied CBUSYN SIP SIP bus control CM CMControl1 communications module CMITN CM SIP interrupt interruptData 16 data bus DATON, DATFN SIP SIP data bus CM CMControl1 initialization INITN SIP CM initializationControl1 I/O READ command IORON SIP CM exchange sync. signalControl1 store WRITE command IOWON SIP CM exchange sync. signalControl1 store READ command MRDON CM SIP exchange sync. signalControl1 store WRITE command MWTON CM SIP exchange sync. signalControl1 XFER recognition XACKN CM SIP exchange sync. signal SIP CM__________________________________________________________________________ LIST OF REFERENCES (1) E. Douglas Jensen "The Honeywell Experimental Distributed Processor A Overview". Computer, January 1978, p 28-38. (2) Heart F.E., Ornstein S.M., Crowther W.R. & Barker W.B. "A New Minicomputer/Multiprocessor for the ARPA Network" NCC (1973) p (3) Ornstein S.M., Crowther W.R., Kraley M.F., Bressler R.D. & Michel A. "Pluribus A Reliable Multiprocessor" NCC (1975) p (4) Vidas B. Glydys & Judith A. Edwards "Optimal Partitioning Of Workload for Distributed Systems" Digest of Papers, Compcon 76 Fall, September 1976, p 353-357. (5) Thomal O. Wolff "Improvements In Realtime Distributed Control". Diges of Papers, Compcon 77 Fall, September 1977, p (6) Le Cann G. "A Protocal to Achieve Distributed Control In Failure Tolerant Multicomputer Systems". SIRIUS Research Report IRIA CRTI 002 1977. (7) Farber D.J. "A Distributed Computer System". Report 4, Dept. Of Information And Computer Sciences, University of California, Irvine, U.S.A. | A distributed data processing system including a general, communications network, and a plurality of local systems which each include a central processing unit, associated memory, and at least one peripheral device. The control of the intercommunication is effected by respective systems intercommunication processors, each attaching one local system to the network. Each SIP has a programmed processor, a local and a network interface, and a bidirectional buffer. The system intercommunications processor will provide for address and code parameter translation, resource requesting and allocating access granting and protecting of the local resources and information objects, while sharing resources among plural requesters. Also failure management and control panel simulation is effected by the systems intercommunications processor. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to telescoping booms and more particularly to telescoping boom extensions and retraction systems.
2. Prior Art
Multi-section telescoping booms are well known to the art and include, for examle, three section booms having three nestled together boom sections one of which is stationary and two of which are extensible with the innermost boom section being extensible with respect to the intermediate boom section from a forward end of the intermediate boom section and the intermediate boom section being extensible with respect to the stationary boom section from a forward end of the stationary boom section.
Such devices have, in the past, included hydraulic or pneumatic cylinders which operate between the stationary boom section and one of the extensible boom sections. Although it is known to the art to attach one end of the cylinder to the stationary section and another end of the cylinder to the most extensible of the boom sections, since the amount of extension which can exist for an ordinary cylinder is less than twice its retracted length, such devices are not favored for three section booms.
In other embodiments, a plurality of hydraulic cylinders have been used with a first hydraulic cylinder connected between the stationary and the intermediate boom section and a second hydraulic cylinder connected between the intermediate and the most extensible boom section. Such constructions have a noticeable disadvantage in requiring two cylinders and further require complicated pressure hose connections to supply pressure to the separate cylinders.
In order to reduce the complexity of such devices, it has been known to utilize chains or cables connecting various boom sections. For the most part, such prior constructions using chains or cables generally mounted the chains or cables, at least in part, exteriorly of the boom section. This external mounting, in addition to giving a bad appearance left operating portions of the system exposed to the elements and unprotected from damage or abrasion during operation.
Additionally, where such chains or cables had been previously used, it was often necessary to provide a separate take-up reel controlling actuation and take-up of the cable. Thus two actuation systems were needed, one for the hydraulic system where that was used and a second for the cable system.
It would be an advance in the art to provide a system which did not rely upon any external chains or cables and which did not require any separate actuation systems but which eliminated the necessity of multiple pneumatic or hydraulic cylinders while allowing boom extension of an amount greater than twice the collapsed length of one cylinder.
SUMMARY OF THE INVENTION
My invention overcomes disadvantages inherent in the above described art. The invention is herewith disclosed in connection with a three section boom consisting of a stationary section, an intermediate extensible section and an inner, most extensible section. Hereinafter these sections will be referred to as stationary, intermediate and inner sections respectively.
Primary telescoping force is provided by an extensible member such as an hydraulic cylinder which is connected between the stationary member and the intermediate member. The hydraulic cylinder which consists of a cylinder together with telescoping piston rod is positioned interior of the inner section and has one end attached to the base end of the stationary section and a second, remote end attached to a channel member end remote from the base end. The channel member has an end adjacent the base end which is connected to the intermediate section at the base end of the intermediate section. Thus actuation of the hydraulic cylinder will cause movement of the intermediate section in or out of the stationary section.
Movement of the inner section is controlled by cables with each cable having one end anchored to the base end of the stationary section and the opposite end anchored to the stationary section adjacent its forward or free end. The cables pass from the base section outwardly towards the free end through the inner section. Adjacent the free end the cable passes around a sheave attached to the free end of the hydraulic cylinder and the returns towards the base end interior of the inner section. At the base end the cable then passes around a sheave attached to the base end of the intermediate section. The cable then extends towards the free end between the intermediate and stationary sections and is anchored adjacent the free end of the stationary section. A clamp member attached to the inner section adjacent the base end of the inner section clamps the cable to the inner section.
Although both ends of the cable remain stationarily attached to the stationary section of the boom, as the hydraulic cylinder is moved, the distance between the cable anchor on the base end of the stationary section and the sheave attached to the free end of the hydraulic cylinder increases. This increase in cable length for that stretch causes corresponding decrease in the length of the cable between the sheave around the free end of the cylinder and the clamp to the cable between the inner boom section and the cable. This causes movement of the clamp relative to both the stationary section and the intermediate boom section thereby causing extension of the inner boom section with respect to the intermediate section at the same time that the intermediate section is being extended with respect to the stationary section. The movement of the cable is such that there is synchronised movement of the boom sections. This movement is on a 1 to 1 ratio and is synchronised in both sections and is such that when the intermediate section is fully extended with respect to the base section, the inner section will be fully extended with respect to the intermediate section.
Upon reversal of the hydraulic cylinder occasioning a withdrawl of the intermediate section into the base section, the respective cable distance will again change. There will be an increase in the length of the portion of the cable between the free end of the stationary section and the sheave on the intermediate section which causes a relative decrease in the cable length between the base end of the stationary section and the sheave on the cylinder rod. This causes a relative movement of the cable stretch between sheave on the cylinder rod and the clamp between the cable and the inner boom section. Thus the inner boom section will be automatically withdrawn upon retraction of the intermediate boom section.
It can therefore be seen that my invention provides for automatic extension and retraction of the most extensible of the boom sections by means of a cable and sheave system located interiorly of the extensible boom which cable and sheave system automatically causes movement of the inner section of the boom in direct response to movement of the intermediate section of the boom with respect to the base section.
It is therefore an object of this invention to provide an improved telescoping boom assembly having at least two extensible boom sections and a stationary boom section.
It is another, more particular, object of this invention to provide an improved extensible boom system having three telescoping boom sections with an outer stationary boom section, an intermediate boom section extensible with respect to the outer boom section and an inner boom section extensible with respect to both the intermediate and outer booms whereby the inner boom section is the most extensible of the sections with movement of the inner boom controlled by a cable and sheave system located entirely interiorly of the boom assembly and with movement of the intermediate boom section controlled by a hydraulic cylinder having one end attached to the stationary boom section with a cylinder assembly intermediate portion extending through the inner boom section and terminating in a free end which has a channel member attached thereto, the channel member being positioned interior of the inner boom section and being attached to the intermediate section adjacent a base end of the intermediate section with a cable length having an end anchored to the stationary section adjacent a base end of the stationary section, the cable extending from the base end anchor interiorly of the innermost section to the free end of the cylinder thence around a sheave and back through the innermost section towards a base end thereof thence around a sheave attached adjacent a base end of the intermediate section thence between the intermediate and stationary sections to an anchor adjacent the free end of the stationary section, the cable clamped to the inner boom section and controlling extension and retraction thereof.
Other objects, features and advantages of the invention will be readily apparent from the following description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure, and in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic, perspective view of an extensible working platform vehicle equipped with the boom assembly of this invention.
FIG. 2 is a fragmentary perspective view of the boom assembly of this invention with portions thereof broken away to show underlying portions and with interior portions illustrated by broken lines.
FIG. 3 is a cross section of the boom assembly of this invention taken generally along the lines III--III of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates an extensible platform vehicle 10 which includes a vehicle base section 11 having wheels 12 which may be articulatable and powered. A boom base 13 is carried on the vehicle base 11 through a rotating connection 14 allowing the boom base 13 to rotate in a horizontal plane with respect to the base 11. A boom assembly 15 is pivotably mounted as at 16 to the boom base 13 and may be elevated or lowered with respect thereto by means such as hydraulic jacks 17. The boom 15 has a base end portion 22 adjacent the pivot 16 and a free end portion 23 remote from the pivot. A work platform 18 may be attached to the free end portion 23 and be capable of supporting one or more workers and associated equipment.
Normally the platform 18 is attached to the free end portion 23 through an articulated connection allowing the platform to be automatically or manually leveled irrespective of the angle of inclination of the boom with respect to the horizontal. Additionally the platform 18, as well as the base 13 may be equipped with suitable controls for raising or lowering the boom, for telescoping the boom, for rotating the boom base 13 on the vehicle base 11, and if desired, for driving and steering the vehicle base 11.
Extension of the boom is accommodated through three telescoping sections including a stationary section 19 having a base end attached to the pivot 16, an intermediate section 20 telescoped in the base section 19 and an inner section 21 telescoped in the intermediate section 20. The inner section 21 thus constitutes the most extensible of the sections in that it can be telescoped outwardly the greatest distance with respect to the boom base 13.
FIG. 1 illustrates various elevations of the boom from a depressed elevation 25 through a horizontal elevation 26 to a raised elevation 27.
FIG. 2 illustrates the boom assembly 15 in greater detail showing the nestling of the inner boom section 21 in the intermediate boom section 20 which in turn is nestled in the stationary boom section 19.
The stationary boom section 19 has a base end 30 which is attached to the pivot 16 and a free end 31 remote from the base end. In the illustrated embodiment the base section, the intermediate section and the inner section are generally rectangular in cross section and are open at both longitudinal ends. When in the collapsed or retracted position, there is a space 32 between the base end 33 of the intermediate section 20 and the base end 30 of the stationary section 19. There is also a space between the base end 34 of the inner section 21 and the base end 33 of the intermediate section 20.
Conversely the free end 35 of the inner section 21 projects beyond the free end 36 of the intermediate section and the free end 31 of the stationary section. In the embodiment illustrated the free end of the intermediate section has been broken away.
Adjacent the base end 30 of the stationary section 19 a cross bar 40 spans the interior of the rectangular base section. The cross bar 40 is positioned off center of the base section and forms an anchor block for a power cylinder 41 such as a pneumatic cylinder. The power cylinder extends longitudinally of the boom assembly interior of the inner section and, in a known manner, includes a piston rod 42 which terminates interior of the inner section adjacent the free end 35 thereof but which is not affixed to the inner section. A channel member 44, which in the illustrated embodiment is a rectangular cross section hollow member surrounds the pneumatic cylinder 41 and piston rod 42 and extends from the free end of the piston rod 42 to adjacent the base end 33 of the intermediate section 20. Overlapping brackets 45 on the base end 33 of the intermediate section and on the base end 46 of the channel member 44 attach the channel member 44 to the intermediate section 20. Attachment may be by means of bolts or the like.
The channel member 44 is attached to the free end of the cylinder's piston rod as by means of an axle member 48 which passes through openings in side walls of the channel member 44 and through an eye opening in the end of the cylinder rod. Sheaves 49 and 50 may be attached to the shaft 48 exterior of the channel member 44 and interior of the inner section 21.
Thus as the hydraulic cylinder 41 is activated to extend the piston rod 42 out of the free end of the hydraulic cylinder, movement of the piston rod is transferred to movement of the channel member 44 through the shaft connection 48. Movement of the channel member 44 causes movement of the intermediate member 20 by means of the connection 45. In this manner, although the hydraulic cylinder is located interior of the inner section 21 it causes direct movement, not of the inner section 21 but of the intermediate section 20. The connection 45 with the bracket member 44 is possible due to the extension of the base end 33 of the intermediate member beyond the base end 34 of the inner member in the direction of the base end 32 of the stationary member when the boom is fully collapsed.
In order to cause movement of the inner member 21 cables 50 are provided. Each of the cables 50 has a base end 51 anchored to the cross bar 40 in the base end of the stationary member and has a free end 52 anchored to a cross bar 53 at the free end 31 of the stationary section 19. The cable 50 has a first stretch 55 which extends from the anchor end 51 to the free end of the piston rod 42 then around one of the sheaves 49, 50. The cable 50 then has an intermediate stretch 56 extending from the sheave 49, 50 back towards the base end to a sheave 54 projecting from the base end 33 of the intermediate section. A third stretch 56 of the cable 50 extends from the sheave 54 to the free end anchor 52. The first and intermediate stretches 55 and 56 project longitudinally interior of the inner section 21. The third stretch 57 extends longitudinally between the intermediate section 20 and the stationary section 19.
The intermediate stretch 56 is attached to the inner section 21 adjacent the base end thereof 34 by means of a clamp member 60.
In the preferred embodiment two cables 50 are used located on either side of the centrally disposed pneumatic cylinder 41 with one cable passing around the sheave 49 and another cable passing around the sheave 50. In this instance there are two sheaves 54 and 54a attached to the base end 33 of the intermediate section 20. The inner section 21 is thus firmly clamped adjacent its base end 34 to one point of the intermediate stretch 56 of each of the cables. As the sheave 49 or 50 moves with respect to the stationary section 19 by extension of the piston rod 42, the corresponding sheave 54, 54a will also be moved an equal distance with respect to the stationary section. This will cause a lengthening of the cable stretch 55 and a shortening of the cable stretch 57. This relative lengthening and shortening of the stretches 55 and 57 requires a movement of the cable in intermediate stretch 56 since the position of the sheaves 49, 50 and 54, 54a are fixed with respect to one another. Movement of the cable within stretch 56 will, because of the anchors 60 cause an equal distance movement of the inner secton 21. The distance the inner section will be moved with respect to the intermediate section is one to one which, however, translates to a 2 to 1 movement with respect to the stationary section. In this manner as the intermediate section is moved relative to the stationary section under influence of the hydraulic cylinder, the inner section will be moved relative to the intermediate section.
The action is the same upon contraction of the system from an extended boom position by withdrawal of the piston rod 42 into the cylinder 41. In such a movement the cable stretch 55 will become shorter whereas the cable stretch 57 will become longer again requiring a corresponding movement of the cable in constant length intermediate stretch 56.
In order to allow relative movement of the channel member 44 with respect to the inner section, a spacer member 70 is attached to the bracket member. The spacer member 70 is, in the preferred embodiment, U-shaped having outturned flanges 71 on the free ends of the legs of the U with the bight of the U attached to a side wall of the bracket member 44 as illustrated in FIG. 3. Thus the outturned flanges 71 form slide surfaces and the hollow interior 72 can function as a conduit for control wires and the like between the platform and the boom base 13. Wear pads 73 can be positioned between the bracket member 44 and the inner face of the inner section 21 on the opposite side of the inner section 21 from the member 70. Additionally wear pads 74 can be provided between the inner section and the intermediate section and between the intermediate section and the stationary section. Preferably the wear pads 74 are positioned on all four sides of each of the sections and in order to allow telescoping of the sections without cocking of the one section within the other, the wear pads 74 are properly disposed on the inside faces of the intermediate and stationary sections adjacent their free ends and on the outside faces of the intermediate and inner sections adjacent their base ends.
It can therefore be seen from the above that my invention provides method and means for extending the boom sections of a three section boom including a hydraulic cylinder connection between a stationary boom section and an intermediate boom section with the hydraulic cylinder positioned interior of an inner boom section and a cable connection between stationary, intermediate and inner sections and the hydraulic cylinder causing movement of the inner section relative to the intermediate and base sections such that the inner section will be automatically telescoped inwardly or outwardly of the intermediate section in direct response to movement of the intermediate section relative to the stationary section under the influence of the hydraulic system. All of the drive assemblies including the hydraulic section, the cables and associated sheaves are positioned interior of the boom assembly where they are protected from the elements and from abrasion and wear during usage.
Although I have described my invention in connection with rectangular booms and involving two cables with a hydraulic cylinder, it is to be understood that variations of this assembly can be provided including, for example, hexagonal, octagonal or the like boom sections, one, three or more cables or cables which are made up of two or more sections or other variants.
Although the teachings of my invention have herein been discussed with reference to specific theories and embodiments, it is to be understood that these are by way of illustration only and that others may wish to utilize my invention in different designs or applications. | An extension and retraction mechanism for a three section extensible boom is disclosed utilizing an internally disposed hydraulic cylinder connected between a stationary boom section and an intermediate boom section with a cable connection located entirely interior of the boom having opposite ends anchored to opposite ends of the stationary section with the cable routed around sheaves on the moving end of the hydraulic cylinder and a base end of the intermediate boom section with a cable attachment to the base end of the inner boom section, the inner boom section being the most extensible boom section. | 1 |
[0001] This application claims priority under 35 U.S.C. 365(c) from PCT/IB2010/052856, filed 23 Jun. 2010, the disclosure of which is incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The field of the invention is medicinal chemistry. The invention relates to N-(2-oxo-1-phenylpiperidin-3-yl)sulfonamides useful for the identification of biological and pharmacological activity in drug discovery.
BACKGROUND OF THE INVENTION
[0003] Novel compounds are continually sought after to treat and prevent diseases and disorders. Pharmaceutical companies interested in owning new active molecules develop or purchase chemical compounds or libraries in order to screen their activity against a particular target, aiming at the identification of new industrially useful products.
[0004] Therefore, there is a market of customer companies for which the acquisition of novel chemical compounds, not already biologically explored, is a key issue. And for the companies whose core business is the design and preparation of chemical compounds or chemical libraries, their commercialization has a clear industrial interest.
[0005] Although many research groups work to find novel compounds to be used in the treatment of known or novel diseases, the number of active new chemical entities in the market doesn't grow in the same extension. Over the past few years, there has been a progressive reduction in the number of medicines entering the market mainly due to the more stringent regulatory requirements that have raised the bar on safety and efficacy of new drugs.
[0006] The compounds described in this invention are useful for contributing to the exploration of the chemical space, for incrementing the structural diversity of valuable molecules in the pharmaceutical sector and for incrementing the elements of structural recognition in order to study their interaction with or modulation of targets of pharmaceutical or medicinal chemistry interest. For instance, the molecules may be therapeutically useful as anti-inflammatory or anticoagulation agents, among many other applications.
[0007] Compounds described in this invention are useful for being biologically and pharmaceutically explored, and therefore to contribute in the research and identification of new drug leads exhibiting the ability of target modulation, since these molecules are sources of chemical diversity not currently explored. The compounds of the present invention may be explored by means of any known method of biological screening. These methods comprise, but are not limited to, receptor affinity assays, ELISA assays, “southern”, “western” and “northern blot”, and competitive binding assays.
[0008] U.S. Pat. No. 7,126,006 B2 (The Scripps Research Institute) describes glycoluryl type molecules as scaffolds in the preparation of combinatorial libraries.
[0009] U.S. Pat. No. 6,939,973 B1 (The Scripps Research Institute) describes glycoluryl type molecules as scaffolds in the preparation of combinatorial libraries.
[0010] Smallheer et al. (Bioorganic & Medicinal Chemistry Letters (2008), 18(7), 2428-2433) disclose a series of sulfonamidolactams useful as coagulation Factor Xa inhibitors.
[0011] WO2004041776 (Bristol-Myers Squibb Company) discloses certain sulfonylamino-valerolactams that can be used as inhibitors of trypsin-like serine proteases, specifically factor Xa.
[0012] WO2002102380 (Bristol-Myers Squibb Pharma. Co.) discloses monocyclic and bicyclic carbocycles and heterocycles active as factor Xa inhibitors.
[0013] The search for novel drug lead compounds for drug discovery is a difficult task that has traditionally required the use of hundreds of thousands of compounds to reach a successful molecule, mainly due to the fact that drug discovery was driven by random screening and the chemical and biological intuition.
[0014] However, integrated approaches combining structural knowledge from conformationally constrained small peptides and parallel synthesis of small molecules are particularly well suited for the shortening of the time-consuming drug discovery process.
[0015] Compounds of formula (I) have been designed using computational techniques such as virtual library screening based on pharmacophore search. Virtual (database) screening (VS) is an important component of the computer-based search of novel lead compounds. The primary VS premise is to screen a database of molecules computationally using structural descriptors that relate in some way to potential biological activity. A subset of database molecules found to match these descriptors can then be selected for subsequent biological analysis. In terms of novel lead discovery, pharmacophore searching is one of the most widely applied VS methods.
[0016] Compounds of formula (I) are not an arbitrary selection of a vast amount of molecules. On the contrary, they have been designed using as starting point a pharmacophore for at least BK antagonism. In this context, a pharmacophore is defined as a critical arrangement of molecular fragments or features creating a necessary, although not sufficient, condition for biological activity and receptor affinity.
[0017] In order to improve the success of molecular bioactive conformations, applicants have defined the structure of compounds of formula (I) using a pharmacophore based on Hoe 140, the most potent peptide antagonist of brakykinin (BK, sequence: D-Arg 0 -Arg 1 -Pro 2 -Hyp 3 -Gly 4 -Thi 5 -Ser 6 -D-Tic 7 -Oic 8 -Arg 9 (Hyp, hydroxyproline; Thi, β-(2-thienyl)-alanine; Tic, 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid; Oic, (2S,3aS,7aS)-octahydroindole-2-carboxylic acid). The pharmacophore for BK antagonism has been obtained from a conformational search using an iterative simulated annealing procedure. Corcho, F J. Computational Studies on the Structure and Dynamics of Bioactive Peptides, PhD Thesis, 2004.
[0018] In conclusion, all compounds of formula (I) exhibit at least Hoe 140 pharmacophore fulfillment, and therefore they share specific characteristics for receptor affinity critical in the search of novel bioactive molecules.
DESCRIPTION OF THE INVENTION
[0019] The present invention concerns the compounds represented by formula (I)
[0000]
[0000] and the salts and stereoisomers thereof, wherein
R 1 is hydrogen, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxy-C 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, aryl, Het; R 2 is C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring; R 3 is hydrogen, C 1-6 alkylcarbonyl, C 1-6 alkyl optionally substituted with aryl, C 1-6 alkoxyC 1-6 alkyl, or C 3-7 cycloalkyl, C 1-6 alkyl optionally substituted with Het; R 4 is hydrogen, hydroxy, halo, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl or C 3-7 cycloalkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, C 1-6 alkyl optionally substituted with aryl or Het; C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring; n is one, two, three, four or five; p is one, two, three, four or five, independently of n; each aryl as a group or part of a group is phenyl or naphthalenyl, each optionally substituted with one, two or three substituents selected from halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy; each Het as a group or part of a group is a monocyclic ring with 5 or 6 ring atoms or a bicyclic ring structure comprising a 6 membered ring fused to a 4, 5, or 6 membered ring; each of the rings being saturated, partially unsaturated, or completely unsaturated; at least one of the rings containing 1 to 4 heteroatoms each independently selected from nitrogen, oxygen and sulphur; and any one of the rings being optionally substituted with one, two or three substituents each independently selected from the group consisting of halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, polyhaloC 1-6 alkoxy, and C 3-7 cycloalkyl.
[0028] The invention further relates to methods for the preparation of the compounds of formula (I), the N-oxides, addition salts, quaternary amines, metal complexes, and stereochemically isomeric forms thereof, their intermediates, and the use of the intermediates in the preparation of the compounds of formula (I).
[0029] The invention relates to the compounds of formula (I) per se, the N-oxides, addition salts, quaternary amines, metal complexes, and stereochemically isomeric forms thereof, for use as lead compounds to be biologically and pharmacologically explored in the search and identification of new drugs.
[0030] As used in the foregoing and hereinafter, the following definitions apply unless otherwise noted.
[0031] The term halo is generic to fluoro, chloro, bromo and iodo.
[0032] The term “polyhaloC 1-6 alkyl” as a group or part of a group, e.g. in polyhaloC 1-6 alkoxy, is defined as mono- or polyhalo substituted C 1-6 alkyl, in particular C 1-6 alkyl substituted with up to one, two, three, four, five, six, or more halo atoms, such as methyl or ethyl with one or more fluoro atoms, for example, difluoromethyl, trifluoromethyl, trifluoroethyl. Preferred is trifluoromethyl. Also included are perfluoroC 1-6 alkyl groups, which are C 1-6 alkyl groups wherein all hydrogen atoms are replaced by fluorine atoms, e.g. pentafluoroethyl. In case more than one halogen atom is attached to an alkyl group within the definition of polyhaloC 1-6 alkyl, the halogen atoms may be the same or different.
[0033] As used herein “C 1-4 alkyl” as a group or part of a group defines straight or branched chain saturated hydrocarbon radicals having from 1 to 4 carbon atoms such as for example methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl; “C 1-6 alkyl” encompasses C 1-4 alkyl radicals and the higher homologues thereof having 5 or 6 carbon atoms such as, for example, 1-pentyl, 2-pentyl, 3-pentyl, 1-hexyl, 2-hexyl, 2-methyl-1-butyl, 2-methyl-1-pentyl, 2-ethyl-1-butyl, 3-methyl-2-pentyl, and the like. Of interest amongst C 1-6 alkyl is C 1-4 alkyl.
[0034] The term “C 2-6 alkenyl” as a group or part of a group defines straight and branched chained hydrocarbon radicals having saturated carbon-carbon bonds and one double bond, and having from 2 to 6 carbon atoms, such as, for example, ethenyl (or vinyl), 1-propenyl, 2-propenyl (or allyl), 1-butenyl, 2-butenyl, 3-butenyl, 2-methyl-2-propenyl, 2-pentenyl, 3-pentenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 2-methyl-2-butenyl, 2-methyl-2-pentenyl and the like. Of interest amongst C 2-6 alkenyl is C 2-4 alkenyl.
[0035] C 3-7 cycloalkyl is generic to cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and cycloheptyl.
[0036] C 1-6 alkoxy means C 1-6 alkyloxy wherein C 1-6 alkyl is as defined above.
[0037] It should be noted that the radical positions on any molecular moiety used in the definitions may be anywhere on such moiety as long as it is chemically stable.
[0038] Radicals used in the definitions of the variables include all possible positional isomers unless otherwise indicated. For instance pyridyl includes 2-pyridyl, 3-pyridyl and 4-pyridyl; pentyl includes 1-pentyl, 2-pentyl and 3-pentyl.
[0039] When any variable occurs more than one time in any constituent, each definition is independent.
[0040] Whenever used hereinafter, the term “compounds of formula (I)”, or “the present compounds” or similar terms, it is meant to include the compounds of formula (I), each and any of the subgroups thereof, N-oxides, addition salts, quaternary amines, metal complexes, and stereochemically isomeric forms.
[0041] The present disclosure also includes the prodrugs of compounds of formula (I).
[0042] One embodiment comprises the compounds of formula (I) or any subgroup of compounds of formula (I) specified herein, as well as the N-oxides, salts, as the possible stereoisomeric forms thereof. Another embodiment comprises the compounds of formula (I) or any subgroup of compounds of formula (I) specified herein, as well as the salts as the possible stereoisomeric forms thereof.
[0043] The compounds of formula (I) may have one or more centers of chirality and may exist as stereochemically isomeric forms. The term “stereochemically isomeric forms” as used herein defines all the possible compounds made up of the same atoms bonded by the same sequence of bonds but having different three-dimensional structures which are not interchangeable, which the compounds of formula (I) may possess.
[0044] With reference to the instances where (R) or (S) is used to designate the absolute configuration of a chiral atom within a substituent, the designation is done taking into consideration the whole compound and not the substituent in isolation.
[0045] Unless otherwise mentioned or indicated, the chemical designation of a compound encompasses the mixture of all possible stereochemically isomeric forms, which said compound may possess. Said mixture may contain all diastereomers and/or enantiomers of the basic molecular structure of said compound. All stereochemically isomeric forms of the compounds of the present invention both in pure form or mixed with each other are intended to be embraced within the scope of the present invention.
[0046] Pure stereoisomeric forms of the compounds and intermediates as mentioned herein are defined as isomers substantially free of other enantiomeric or diastereomeric forms of the same basic molecular structure of said compounds or intermediates. In particular, the term “stereoisomerically pure” concerns compounds or intermediates having a stereoisomeric excess of at least 80% (i.e. minimum 90% of one isomer and maximum 10% of the other possible isomers) up to a stereoisomeric excess of 100% (i.e. 100% of one isomer and none of the other), more in particular, compounds or intermediates having a stereoisomeric excess of 90% up to 100%, even more in particular having a stereoisomeric excess of 94% up to 100% and most in particular having a stereoisomeric excess of 97% up to 100%. The terms “enantiomerically pure” and “diastereomerically pure” should be understood in a similar way, but then having regard to the enantiomeric excess, and the diastereomeric excess, respectively, of the mixture in question.
[0047] Pure stereoisomeric forms of the compounds and intermediates of this invention may be obtained by the application of art-known procedures. For instance, enantiomers may be separated from each other by the selective crystallization of their diastereomeric salts with optically active acids or bases. Examples thereof are tartaric acid, dibenzoyltartaric acid, ditoluoyltartaric acid and camphosulfonic acid. Alternatively, enantiomers may be separated by chromatographic techniques using chiral stationary phases. Said pure stereochemically isomeric forms may also be derived from the corresponding pure stereochemically isomeric forms of the appropriate starting materials, provided that the reaction occurs stereospecifically. Preferably, if a specific stereoisomer is desired, said compound will be synthesized by stereospecific methods of preparation. These methods will advantageously employ enantiomerically pure starting materials.
[0048] The diastereomeric racemates of the compounds of formula (I) can be obtained separately by conventional methods. Appropriate physical separation methods that may advantageously be employed are, for example, selective crystallization and chromatography, e.g. column chromatography.
[0049] For some of the compounds of formula (I), their N-oxides, salts, solvates, quaternary amines, or metal complexes, and the intermediates used in the preparation thereof, the absolute stereochemical configuration was not experimentally determined. A person skilled in the art is able to determine the absolute configuration of such compounds using art-known methods such as, for example, X-ray diffraction.
[0050] The present invention is also intended to include all isotopes of atoms occurring on the present compounds. Isotopes include those atoms having the same atomic number but different mass numbers. By way of general example and without limitation, isotopes of hydrogen include tritium and deuterium. Isotopes of carbon include C-13 and C-14.
[0051] The term “prodrug” as used throughout this text means the pharmacologically acceptable derivatives such as esters, amides, and phosphates, such that the resulting in vivo biotransformation product of the derivative is the active drug as defined in the compounds of formula (I). The reference by Goodman and Gilman (The Pharmacological Basis of Therapeutics, 8th ed, McGraw-Hill, Int. Ed. 1992, “Biotransformation of Drugs”, p 13-15) describing prodrugs generally is hereby incorporated. Prodrugs preferably have excellent aqueous solubility, increased bioavailability and are readily metabolized into the active inhibitors in vivo. Prodrugs of a compound of the present invention may be prepared by modifying functional groups present in the compound in such a way that the modifications are cleaved, either by routine manipulation or in vivo, to the parent compound.
[0052] Preferred are pharmaceutically acceptable ester prodrugs that are hydrolysable in vivo and are derived from those compounds of formula (I) having a hydroxy or a carboxyl group. An in vivo hydrolysable ester is an ester, which is hydrolyzed in the human or animal body to produce the parent acid or alcohol. Suitable pharmaceutically acceptable esters for carboxy include C 1-6 alkoxymethyl esters for example methoxymethyl, C 1-6 alkanoyloxymethyl esters for example pivaloyloxymethyl, phthalidyl esters, C 3-8 cycloalkoxycarbonyloxyC 1-6 alkyl esters for example 1-cyclohexylcarbonyloxyethyl; 1,3-dioxolen-2-onylmethyl esters for example 5-methyl-1,3-dioxolen-2-onylmethyl; and C 1-6 alkoxycarbonyloxyethyl esters for example 1-methoxycarbonyl-oxyethyl which may be formed at any carboxy group in the compounds of this invention.
[0053] An in vivo hydrolysable ester of a compound of the formula (I) containing a hydroxy group includes inorganic esters such as phosphate esters and α-acyloxyalkyl ethers and related compounds which as a result of the in vivo hydrolysis of the ester breakdown to give the parent hydroxy group. Examples of α-acyloxyalkyl ethers include acetoxymethoxy and 2,2-dimethylpropionyloxy-methoxy. A selection of in vivo hydrolysable ester forming groups for hydroxy include alkanoyl, benzoyl, phenylacetyl and substituted benzoyl and phenylacetyl, alkoxycarbonyl (to give alkyl carbonate esters), dialkylcarbamoyl and N-(dialkylaminoethyl)-N-alkylcarbamoyl (to give carbamates), dialkylaminoacetyl and carboxyacetyl. Examples of substituents on benzoyl include morpholino and piperazino linked from a ring nitrogen atom via a methylene group to the 3- or 4-position of the benzoyl ring.
[0054] For therapeutic use, salts of the compounds of formula (I) are those wherein the counter-ion is pharmaceutically acceptable. However, salts of acids and bases which are non-pharmaceutically acceptable may also find use, for example, in the preparation or purification of a pharmaceutically acceptable compound. All salts, whether pharmaceutically acceptable or not are included within the ambit of the present invention.
[0055] The pharmaceutically acceptable acid and base addition salts as mentioned hereinabove are meant to comprise the therapeutically active non-toxic acid and base addition salt forms which the compounds of formula (I) are able to form. The pharmaceutically acceptable acid addition salts can conveniently be obtained by treating the base form with such appropriate acid. Appropriate acids comprise, for example, inorganic acids such as hydrohalic acids, e.g. hydrochloric or hydrobromic acid, sulfuric, nitric, phosphoric and the like acids; or organic acids such as, for example, acetic, propanoic, hydroxyacetic, lactic, pyruvic, oxalic (i.e. ethanedioic), malonic, succinic (i.e. butanedioic acid), maleic, fumaric, malic (i.e. hydroxybutanedioic acid), tartaric, citric, methanesulfonic, ethanesulfonic, benzenesulfonic, p-toluenesulfonic, cyclamic, salicylic, p-aminosalicylic, pamoic and the like acids.
[0056] Conversely said salt forms can be converted by treatment with an appropriate base into the free base form.
[0057] The compounds of formula (I) containing an acidic proton may also be converted into their non-toxic metal or amine addition salt forms by treatment with appropriate organic and inorganic bases. Appropriate base salt forms comprise, for example, the ammonium salts, the alkali and earth alkaline metal salts, e.g. the lithium, sodium, potassium, magnesium, calcium salts and the like, salts with organic bases, e.g. the benzathine, N-methyl-D-glucamine, hydrabamine salts, and salts with amino acids such as, for example, arginine, lysine and the like.
[0058] The term addition salt as used hereinabove also comprises the solvates which the compounds of formula (I) as well as the salts thereof, are able to form. Such solvates are for example hydrates, alcoholates and the like.
[0059] The term “quaternary amine” as used hereinbefore defines the quaternary ammonium salts which the compounds of formula (I) are able to form by reaction between a basic nitrogen of a compound of formula (I) and an appropriate quaternizing agent, such as, for example, an optionally substituted alkylhalide, arylhalide or arylalkylhalide, e.g. methyliodide or benzyliodide. Other reactants with good leaving groups may also be used, such as alkyl trifluoromethanesulfonates, alkyl methanesulfonates, and alkyl p-toluenesulfonates. A quaternary amine has a positively charged nitrogen. Pharmaceutically acceptable counterions include chloro, bromo, iodo, trifluoroacetate and acetate. The counterion of choice can be introduced using ion exchange resins.
[0060] The N-oxide forms of the present compounds are meant to comprise the compounds of formula (I) wherein one or several nitrogen atoms are oxidized to the so-called N-oxide.
[0061] It will be appreciated that the compounds of formula (I) may have metal binding, chelating, complex forming properties and therefore may exist as metal complexes or metal chelates. Such metalated derivatives of the compounds of formula (I) are intended to be included within the scope of the present invention.
[0062] Some of the compounds of formula (I) may also exist in their tautomeric form. Such forms although not explicitly indicated in the above formula are intended to be included within the scope of the present invention.
[0063] One embodiment of the present invention concerns compounds of formula (I) or of any subgroup of compounds of formula (I), wherein one or more of the following conditions apply:
R 1 is hydrogen, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxy-C 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, aryl, Het; R 2 is C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring; R 3 is hydrogen, C 1-6 alkylcarbonyl, C 1-6 alkyl optionally substituted with aryl, C 1-6 alkoxyC 1-6 alkyl, or C 3-7 cycloalkyl, C 1-6 alkyl optionally substituted with Het; R 4 is hydrogen; n is one, two, three, four or five; p is one; each aryl as a group or part of a group is phenyl or naphthalenyl, each optionally substituted with one, two or three substituents selected from halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy; each Het as a group or part of a group is a monocyclic ring with 5 or 6 ring atoms or a bicyclic ring structure comprising a 6 membered ring fused to a 4, 5, or 6 membered ring; each of the rings being saturated, partially unsaturated, or completely unsaturated; at least one of the rings containing 1 to 4 heteroatoms each independently selected from nitrogen, oxygen and sulphur; and any one of the rings being optionally substituted with one, two or three substituents each independently selected from the group consisting of halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, polyhaloC 1-6 alkoxy, and C 3-7 cycloalkyl.
[0072] Another embodiment of the present invention concerns compounds of formula (I) or of any subgroup of compounds of formula (I), wherein one or more of the following conditions apply:
R 1 is hydrogen or C 1-6 alkyl; R 2 is C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; or Het; R 3 is hydrogen, C 1-6 alkyl or carboxyl; R 4 is hydrogen; n is one or two; p is one; each aryl as a group or part of a group is phenyl or naphthalenyl, each optionally substituted with one, two or three substituents selected from halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy; each Het as a group or part of a group is a monocyclic ring with 5 or 6 ring atoms or a bicyclic ring structure comprising a 6 membered ring fused to a 4, 5, or 6 membered ring; each of the rings being saturated, partially unsaturated, or completely unsaturated; at least one of the rings containing 1 to 4 heteroatoms each independently selected from nitrogen, oxygen and sulphur; and any one of the rings being optionally substituted with one, two or three substituents each independently selected from the group consisting of halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, polyhaloC 1-6 alkoxy, and C 3-7 cycloalkyl.
[0081] One embodiment of the present invention concerns compounds of formula (I) or of any subgroup of compounds of formula (I), wherein one or more of the following conditions apply:
R 1 is hydrogen; R 2 is C 2-6 alkenyl optionally substituted with aryl or Het; aryl; or Het; R 3 is hydrogen; R 4 is hydrogen; n is one or two; p is one; each aryl as a group or part of a group is phenyl or naphthalenyl, each optionally substituted with one or two substituents selected from halo, amino, mono- or diC 1-6 alkylamino, and polyhaloC 1-6 alkyl; each Het as a group or part of a group is a monocyclic ring with 5 or 6 ring atoms or a bicyclic ring structure comprising a 6 membered ring fused to a 4, 5, or 6 membered ring; each of the rings being saturated, partially unsaturated, or completely unsaturated; at least one of the rings containing 1 to 4 heteroatoms each independently selected from nitrogen, oxygen and sulphur; and any one of the rings being optionally substituted with one or two substituents each independently selected from the group consisting of halo and polyhaloC 1-6 alkyl.
[0090] The compounds of the present invention may be prepared according to the procedures described hereinafter, which are meant to be applicable for as well the racemates, stereochemically pure intermediates or end products, or any stereoisomeric mixtures. The racemates or stereochemical mixtures may be separated into stereoisomeric forms at any stage of the synthesis procedures.
[0000]
[0091] As shown in the above scheme 1, coupling of a compound of formula [4] with the primary amine compound of formula [5] gives the amide derivative compound of formula [6]. The coupling reaction occurs in an organic solvent, such as a chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, at a temperature preferably between −10° C. and 40° C., more preferably between 0° C. and 25° C. Compound of formula [4] comprises a group —CO—R 7 in the form of an activated carboxyl derivative, such as acid chlorides, anhydrides, or active esters such as O-acylisoureas or acyloxyphosphonium derivatives. In a particular embodiment the carbonyl compound is carboxylic acid, the carboxyl activate derivative is O-acylisourea and the activating group is a carbodiimide coupling reagent such as dicyclohexylcarbodiimide (DCC), while in another the coupling group is diisopropylcarbodiimide (DIPC).
[0092] The corresponding reduction or deprotection reaction of compound [6] yields the alcohol of formula [7]. In a particular embodiment, R 6 group is a benzyl protecting group, and the deprotection reaction comprises the chemoselective reduction of the metal hydride with a reductive agent such as NaBH 4 or Ca(BH 4 ) 2 in a polar protic solvent, such as ethanol or 2-propanol at a temperature preferably between −10° C. and 25° C., more preferably between 0° C. and 10° C.
[0093] The activation of compound [7] to furnish compound of formula [8] occurs by means of sulfonyl halides, preferably para-toluenesulfonyl halides, methanesulfonyl halides or trifluoromethanesulfonyl halides, in the presence of an organic aliphatic or aromatic base, such as pyridine, imidazole, or triethylamine. In a particular embodiment, R 8 group is a methanesulfonyl activating group, and the reaction occurs in a chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, in anhydrous or non anhydrous conditions, at a temperature preferably between −10° C. and 40° C., more preferably between 0° C. and 25° C.
[0094] Treatment of compound [8] under cyclisation conditions yields the lactam compound of formula [9] and the pyrrolidine compound of formula [10]. The reaction occurs in the presence of an inorganic or organic base, such as sodium hydride, potassium tert-butoxide or lithium diisopropylamide, at a temperature preferably between −78° C. and 60° C., more preferably between −40° C. and 0° C. The reaction solvent is a polar aprotic solvent, preferably acetonitrile, tetrahydrofuran, dimethylformamide, or dimethylsulfoxide.
[0095] The N-deprotection of compounds [9] and [10] yields compounds of formulae [11] and [12], respectively where R 5 is an amino protecting group, carbamate, urea-type derivative, amide, cyclic imide, alkyl, aryl, imine, enamine or heteroatom. In a particular embodiment, the protecting group is tert-butoxycarbonyl group and the deprotecting agent is trifluoroacetic acid in a chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, at a trifluoroacetic acid composition preferably between 5% and 90%, more preferably between 15% and 70%, at a temperature preferably between 0° C. and 45° C., more preferably between 10° C. and 30° C.
[0096] The substitution reaction of [11] or [12] with compounds of formula R 2 —SO 2 -LG, where LG means “leaving group”, being said LG group preferably an halogen atom, more preferably bromine or chlorine, yields the corresponding substituted sulfonamides of formula [13] and [14], respectively. The reaction solvent is a chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, or a polar aprotic solvent, preferably acetonitrile, tetrahydrofuran, or dimethylformamide, at a temperature preferably between 0° C. and 40° C., more preferably between 10° C. and 25° C.
[0097] Under substitution or coupling conditions with compounds of formula R 3 —Y, where Y means “leaving group” in substitution reaction and “activating group” in coupling reactions, being said Y preferably is a halogen atom, more preferably bromine or chlorine in substitution reaction, or an activated carboxyl derivative in coupling reactions, compounds [13] and [14] are converted to the final compounds of formula [1] and [2], respectively. The reaction solvent is a hydrous or anhydrous polar aprotic solvent, preferably acetonitrile, tetrahydrofuran, or dimethylformamide, at a temperature preferably between −78° C. and 60° C., more preferably between −78° C. and 25° C.
[0098] Both racemic as well as pure enantiomers of [1] and [2] can be accessed by this approach depending on the stereochemical integrity of the starting material.
[0000]
[0099] Alternatively, the compounds of formula [1] or [2] can be prepared by the approach as shown in scheme 2. According to scheme 2, coupling of a compound of formula [4] with the compound of formula [5] gives the amide derivative compound of formula [6]. The coupling reaction occurs in an organic solvent, such as a chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, at a temperature preferably between −10° C. and 40° C., more preferably between 0° C. and 25° C. Compound of formula [4] comprises a group —CO—R 7 in the form of an activated carboxyl derivative, such as acid chlorides, anhydrides, or active esters such as O-acylisoureas or acyloxyphosphonium derivatives. In a particular embodiment the carbonyl compound is carboxylic acid, the carboxyl activate derivative is O-acylisourea and the activating group is a carbodiimide coupling reagent such as dicyclohexylcarbodiimide (DCC), while in another the coupling group is diisopropylcarbodiimide (DIPC).
[0100] The N-deprotection of compound [6] yields compounds of formula [17]. In a particular realization the protecting group is tert-butoxycarbonyl group and the deprotecting agent is trifluoroacetic acid in a chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, at a trifluoroacetic acid composition preferably between 5% and 90%, more preferably between 15% and 70%, at a temperature preferably between 0° C. and 45° C., more preferably between 10° C. and 30° C.
[0101] The coupling reaction of [17] with compounds of formula R 2 —SO 2 -LG, where LG means “leaving group”, being said LG group preferably an halogen atom, more preferably bromine or chlorine, yields the corresponding substituted sulfonamide of formula [18]. The reaction solvent is a chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, or a polar aprotic solvent, preferably acetonitrile, tetrahydrofuran, or dimethylformamide, at a temperature preferably between 0° C. and 40° C., more preferably between 10° C. and 25° C.
[0102] The corresponding reduction or deprotection reaction of compound [18] yields the alcohol of formula [19]. In a particular embodiment, R 6 group is a benzyl protecting group, and the deprotection reaction comprises the chemoselective reduction of the metal hydride with an reductive agent such as NaBH 4 or Ca(BH 4 ) 2 in a polar protic solvent, such as ethanol or 2-propanol at a temperature preferably between −10° C. and 25° C., more preferably between 0° C. and 10° C.
[0103] Activation of compound [19] furnishes compound of formula [20]. The reaction occurs by means of sulfonyl halides, preferably para-toluenesulfonyl halides, methanesulfonyl halides or trifluoromethanesulfonyl halides, in the presence of an organic aliphatic or aromatic base, such as pyridine, imidazole, or triethylamine. The reaction occurs in a chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, in anhydrous or non anhydrous conditions, at a temperature preferably between −10° C. and 40° C., more preferably between 0° C. and 25° C.
[0104] Treatment of compound [20] under cyclisation conditions yields the lactam compound of formula [13] and the pyrrolidine compound of formula [14]. The reaction occurs in the presence of an inorganic or organic base, such as sodium hydride, potassium tert-butoxide or lithium diisopropylamide, at a temperature preferably between −78° C. and 60° C., more preferably between −40° C. and 0° C. The reaction solvent is a polar aprotic solvent, preferably acetonitrile, tetrahydrofuran, dimethylformamide, or dimethylsulfoxide.
[0105] Under substitution or coupling conditions with compounds of formula R 3 —Y, where Y means “leaving group” in substitution reaction and “activating group” in coupling reactions, being said Y preferably is a halogen atom, more preferably bromine or chlorine in substitution reaction, or an activated carboxyl derivative in coupling reactions, compounds [13] and [14] are converted to the final compounds of formula [1] and [2], respectively. The reaction solvent is a hydrous or anhydrous polar aprotic solvent, preferably acetonitrile, tetrahydrofuran, or dimethylformamide, at a temperature preferably between −78° C. and 60° C., more preferably between −78° C. and 25° C. Both racemic as well as pure enantiomers of [1] and [2] can be accessed by this approach depending on the stereochemical integrity of the starting material.
[0106] The compounds of the present invention may be used, biologically and pharmacologically explored in the search and identification of new lead compounds in the drug discovery process. The abovementioned use comprises the compounds of formula (I)
[0000]
[0000] and the salts and stereoisomers thereof, wherein
R 1 is hydrogen, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxy-C 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, aryl, Het; R 2 is C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 1-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring; R 3 is hydrogen, C 1-6 alkylcarbonyl, C 1-6 alkyl optionally substituted with aryl, C 1-6 alkoxyC 1-6 alkyl, or C 3-7 cycloalkyl, C 1-6 alkyl optionally substituted with Het; R 4 is hydrogen, hydroxy, halo, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl or C 3-7 cycloalkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, C 1-6 alkyl optionally substituted with aryl or Het; C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring; n is one, two, three, four or five; p is one, two, three, four or five, independently of n; each aryl as a group or part of a group is phenyl or naphthalenyl, each optionally substituted with one, two or three substituents selected from halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy; each Het as a group or part of a group is a monocyclic ring with 5 or 6 ring atoms or a bicyclic ring structure comprising a 6 membered ring fused to a 4, 5, or 6 membered ring; each of the rings being saturated, partially unsaturated, or completely unsaturated; at least one of the rings containing 1 to 4 heteroatoms each independently selected from nitrogen, oxygen and sulphur; and any one of the rings being optionally substituted with one, two or three substituents each independently selected from the group consisting of halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, polyhaloC 1-6 alkoxy, and C 3-7 cycloalkyl.
[0115] The present invention comprises the use of the compounds of formula (I), their salts and stereoisomers used for being biologically and pharmacologically explored in the search and identification of new lead compounds in the drug discovery process. The abovementioned use comprises the compounds of formula (I)
[0000]
[0000] and the salts and stereoisomers thereof, wherein
R 1 is hydrogen, halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, aryl, Het; R 2 is C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring; R 3 is hydrogen, C 1-6 alkylcarbonyl, C 1-6 alkyl optionally substituted with aryl, C 1-6 alkoxyC 1-6 alkyl, or C 3-7 cycloalkyl, C 1-6 alkyl optionally substituted with Het; R 4 is hydrogen; n is one, two, three, four or five; p is one; each aryl as a group or part of a group is phenyl or naphthalenyl, each optionally substituted with one, two or three substituents selected from halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy; each Het as a group or part of a group is a monocyclic ring with 5 or 6 ring atoms or a bicyclic ring structure comprising a 6 membered ring fused to a 4, 5, or 6 membered ring; each of the rings being saturated, partially unsaturated, or completely unsaturated; at least one of the rings containing 1 to 4 heteroatoms each independently selected from nitrogen, oxygen and sulphur; and any one of the rings being optionally substituted with one, two or three substituents each independently selected from the group consisting of halo, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, polyhaloC 1-6 alkoxy, and C 3-7 cycloalkyl.
[0124] As such, in one embodiment, the present invention relates to a process for preparing a compound of formula (I) as described herein, said process comprising
[0000] a) reacting in a suitable medium compound of formula (II) with a compound of
[0000]
[0000] and
b) optionally further reacting in a suitable medium the product of step a) with R 3 —Y;
wherein
R 1 , R 2 , R 3 , R 4 , n and p have the same definition as provided herein;
LG is a leaving group;
Y is an activating group in coupling reactions or a leaving group in substitution reactions.
[0125] The suitable medium of the reaction in step a) is anhydrous or non anhydrous chlorinated solvent, preferably dichloromethane, 1,2-dichloroethane or chloroform, or a hydrous or anhydrous polar aprotic solvent, preferably acetonitrile, tetrahydrofuran, or dimethylformamide, at a temperature preferably between 0° C. and 40° C., more preferably between 0° C. and 25° C.
[0126] The suitable medium of the reaction in step b) is in the presence of an inorganic or organic base, such as sodium hydride, potassium tert-butoxide or lithium diisopropylamide, at a temperature preferably between −78° C. and 60° C., more preferably between −78° C. and 25° C. The reaction solvent is a polar aprotic solvent, preferably acetonitrile, tetrahydrofuran, dimethylformamide, or dimethylsulfoxide.
[0127] The term “leaving group” is preferably a halogen atom, more preferably bromine or chlorine.
[0128] The term “activating group” is preferably but not limited to a carboxyl activant in coupling reactions, preferably in the form of an acid chloride, anhydride, or active esters, such as O-acylisoureas or acyloxyphosphonium derivatives.
[0129] Compounds of formula (I) may be converted into each other following art-known functional group transformation reactions. For example, amino groups may be N-alkylated, nitro groups reduced to amino groups, a halo atom may be exchanged for another halo.
[0130] The compounds of formula (I) may be converted to the corresponding N-oxide forms following art-known procedures for converting a trivalent nitrogen into its N-oxide form. Said N-oxidation reaction may generally be carried out by reacting the starting material of formula (I) with an appropriate organic or inorganic peroxide. Appropriate inorganic peroxides comprise, for example, hydrogen peroxide, alkali metal or earth alkaline metal peroxides, e.g. sodium peroxide, potassium peroxide; appropriate organic peroxides may comprise peroxy acids such as, for example, benzenecarbo-peroxoic acid or halo substituted benzenecarboperoxoic acid, e.g. 3-chlorobenzenecarboperoxoic acid, peroxoalkanoic acids, e.g. peroxoacetic acid, alkylhydroperoxides, e.g. tert-butyl hydro-peroxide. Suitable solvents are, for example, water, lower alcohols, e.g. ethanol and the like, hydrocarbons, e.g. toluene, ketones, e.g. 2-butanone, halogenated hydrocarbons, e.g. dichloromethane, and mixtures of such solvents.
[0131] Pure stereochemically isomeric forms of the compounds of formula (I) may be obtained by the application of art-known procedures. Diastereomers may be separated by physical methods such as selective crystallization and chromatographic techniques, e.g., counter-current distribution, liquid chromatography and the like.
[0132] The compounds of formula (I) may be obtained as racemic mixtures of enantiomers which can be separated from one another following art-known resolution procedures. The racemic compounds of formula (I), which are sufficiently basic or acidic may be converted into the corresponding diastereomeric salt forms by reaction with a suitable chiral acid, respectively chiral base. Said diastereomeric salt forms are subsequently separated, for example, by selective or fractional crystallization and the enantiomers are liberated therefrom by alkali or acid. An alternative manner of separating the enantiomeric forms of the compounds of formula (I) involves liquid chromatography, in particular liquid chromatography using a chiral stationary phase. Said pure stereochemically isomeric forms may also be derived from the corresponding pure stereochemically isomeric forms of the appropriate starting materials, provided that the reaction occurs stereospecifically. Preferably if a specific stereoisomer is desired, said compound may be synthesized by stereospecific methods of preparation. These methods may advantageously employ enantiomerically pure starting materials.
[0133] One embodiment of the present invention concerns compounds of formula (IV) or any subgroup of compounds of formula (IV), and the salts and stereoisomers thereof, wherein one or more of the following conditions apply
[0000]
wherein
R 1 is hydrogen, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, aryl, Het;
R 4 is hydrogen, hydroxy, halo, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl or C 3-7 cycloalkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, C 1-6 alkyl optionally substituted with aryl or Het; C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring;
R 5 is an amino protecting group, in the form of carbamate, urea-type derivative, amide, cyclic imide, alkyl, aryl, imine, enamine or heteroatom;
n is one, two, three, four or five;
p is one, two, three, four or five, independently of n;
[0140] The invention further relates to compounds of formula (IV) per se, the N-oxides, addition salts, quaternary amines, metal complexes, and stereochemically isomeric forms thereof, for use as synthetic intermediates in the preparation of compounds of formula (I).
[0141] One embodiment of the present invention concerns compounds of formula (V) or any subgroup of compounds of formula (V), and the salts and stereoisomers thereof, wherein one or more of the following conditions apply
[0000]
wherein
R 1 is hydrogen, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxy-C 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, aryl, Het;
R 4 is hydrogen, hydroxy, halo, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl or C 3-7 cycloalkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, C 1-6 alkyl optionally substituted with aryl or Het; C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or
R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring;
R 5 is an amino protecting group, in the form of carbamate, urea-type derivative, amide, cyclic imide, alkyl, aryl, imine, enamine or heteroatom;
R 8 is an hydroxy activating group, preferably in the form of a sulfonate ester, para-toluenesulfonyl, methanesulfonyl or trifluoromethanesulfonyl;
n is one, two, three, four or five;
p is one, two, three, four or five, independently of n;
[0150] The invention further relates to compounds of formula (V) per se, the N-oxides, addition salts, quaternary amines, metal complexes, and stereochemically isomeric forms thereof, for use as synthetic intermediates in the preparation of compounds of formula (I).
[0151] One embodiment of the present invention concerns compounds of formula (VI) or any subgroup of compounds of formula (VI), and the salts and stereoisomers thereof, wherein one or more of the following conditions apply:
[0000]
wherein
R 1 is hydrogen, hydroxy, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxy-C 1-6 alkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, aryl, Het;
R 4 is hydrogen, hydroxy, halo, nitro, cyano, carboxyl, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxyC 1-6 alkyl or C 3-7 cycloalkyl, C 1-6 alkylcarbonyl, amino, mono- or diC 1-6 alkylamino, azido, mercapto, polyhaloC 1-6 alkyl, and polyhaloC 1-6 alkoxy, C 1-6 alkyl optionally substituted with aryl or Het; C 3-7 cycloalkyl optionally substituted with C 1-6 alkyl; C 1-6 alkyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; C 2-6 alkenyl optionally substituted with C 3-7 cycloalkyl, aryl or Het; aryl; Het; or —NR 4a R 4b , wherein R 4a and R 4b are, each independently, C 1-6 alkyl, or R 4a and R 4b together with the nitrogen to which they are attached form a 5- or 6-membered saturated heterocyclic ring;
R 5 is an amino protecting group, carbamate, urea-type derivative, amide, cyclic imide, alkyl, aryl, imine, enamine or heteroatom;
n is one, two, three, four or five;
p is one, two, three, four or five, independently of n;
[0158] The invention further relates to compounds of formula (VI) per se, the N-oxides, addition salts, quaternary amines, metal complexes, and stereochemically isomeric forms thereof, for use as synthetic intermediates in the preparation of compounds of formula (I).
EXAMPLES
[0159] The following examples are intended to illustrate the present invention and not to limit it thereto.
Example 1
Preparation of intermediate [6a]: Benzyl 4-(tert-butoxycarbonyl-amino)-5-oxo-5-(phenylamino)pentanoate
[0160]
[0161] To a stirred solution of Boc-L-glutamic acid 5-benzyl ester [4a] (41 g, 122 mmol) in anhydrous CH 2 Cl 2 (45 ml) at 0° C., was added during 15 minutes a solution of DCC (30.1 g, 146 mmol) in anhydrous CH 2 Cl 2 (45 ml). The resulting white solid was sonicated. After that, anhydrous aniline was added dropwise to the reaction mixture over 10 minutes at 0° C. (11.1 ml, 122 mmol). The mixture was stirred at room temperature for 40 minutes and filtered through Celite® to remove insoluble material. The resulting liquid was evaporated to dryness and chromatographically purified, yielding the desired product (47.2 g, 94%).
[0162] 1 H-NMR (400 MHz, CDCl 3 ): δ: 8.40 (br, 1H, CON H Ph), 7.43 (d, 2H, J=7.7 Hz, 2H a ), 7.28 (d, 2H, J=7.7 Hz, H b ), 7.20 (m, 5H, 5×H d ), 7.02 (t, 1H, J=7.4 Hz, H c ), 5.35 (d, 1H, J=7.8 Hz, CHN H Boc), 5.04 (d, 2H, J=2.6 Hz, BnOC H 2 ), 4.26 (sa, 1H, CH 2 C H NHBoc), 2.60-2.52 (mc, 1H, 1×OCOC H 2 CH 2 ), 2.46-2.38 (mc, 1H, 1×OCOC H 2 CH 2 ), 2.21-2.12 (mc, 1H, 1×OCOC H 2 CH 2 ), 1.99-1.90 (mc, 1H, 1×OCOCH 2 C H 2 ), 1.40 (s, 9H, NHCO 2 C(C H 3 ) 3 ) ppm.
[0163] MS: Positive mode [M+Na] + =435.
[0164] MS: Negative mode [M+2H 2 O−H] − =447.
[0165] CAS nr: [126349-57-3]
Example 2
Preparation of intermediate [7a]: Tert-butyl 5-hydroxy-1-oxo-(phenylamino)pentan-2-ylcarbamate
[0166]
[0167] To a stirred suspension of NaBH 4 (12.5 g, 342 mmol) in 200 ml EtOH at 0° C. was added crushed CaCl 2 (19.9 g, 171 mmol) in portions during 15 min. After that, compound [6a] (35.2 g, 85.8 mmol) was added in portions during 10 minutes. The solution was stirred for 3.5 h, warming to room temperature. The crude was neutralized at 0° C. using HCl 0.1 M, and the aqueous phase was extracted in AcOEt. The organic phase was washed using saturated NaCl, dried over anhydrous Na 2 SO 4 and evaporated to dryness. The resulting oil residue was chromatographically purified over SiO 2 in Hexane/AcOEt (40:60), furnishing the desired product (17.4 g, 65%).
[0168] 1 H-NMR (300 MHz, CDCl 3 ), δ: 8.85 (br, 1H, CONHPh), 7.50 (dd, 2H, J 1 =8.7 Hz, J 2 =1.2 Hz, 2×H a ), 7.27 (dd, 2H, J 1 =8.4 Hz, J 2 =7.8 Hz, 2×H b ), 7.08 (t, 1H, J r =7.2 Hz, H c ), 5.57 (sa, 1H, J=5.7 Hz, CHNHBoc), 4.41 (br, 111, J=5.7 Hz, CHNHBoc), 3.74 (m, 2H, CH 2 OH), 2.94 (br, 1H, CH 2 OH), 2.0-1.65 (mc, 4H, CH 2 CH 2 ), 1.44 (s, 9H, NHCO 2 C(CH 3 ) 3 ) ppm.
[0169] 13 C-NMR (75 MHz, CDCl 3 ), δ: 170.6 ( C ONHPh), 156.2 ( C (CH 3 ) 3 ), 137.7 (NH C O 2 ), 128.9 (C Ar —H b ), 124.3 (C Ar —H c ), 119.9 (C Ar —H a ), 62.4 ( C H 2 OH), 54.6 ( C HNHBoc), 30.1 (CH 2 C H 2 ), 28.3 (NHCO 2 C( C H 3 ) 3 ), 28.0 ( C H 2 CH 2 ) ppm.
[0170] MS: Positive mode [M+H] + =309, [M+Na] + =331.
[0171] MS: Negative mode [M−H] − =307.
Example 3
Preparation of intermediate [8a]: 4-(tert-butoxycarbonylamino)-5-oxo-(phenylamino)pentyl methanesulfonate
[0172]
[0173] To a stirred solution of compound [7a] (0.98 g, 3.19 mmol) in 10 ml anhydrous CH 2 Cl 2 was added 0.66 ml of anhydrous Et 3 N (4.76 mmol, 1.48 eq) at 0° C. To this solution was added MsCl (3.86 mmol, 1.21 eq) and the mixture was stirred for 2 h at 0° C. After then, the crude was evaporated to dryness, and filtered over SiO 2 using AcOEt as the eluant. Once the filtered was evaporated, finally it was crystallized in acetone at 0° C., yielding 1.12 g (91%) of the desired product.
[0174] 1 H-NMR (300 MHz, CDCl 3 ): δ 8.435 (s, 1H), 7.512 (dd, J 1 =7.8 Hz, J 2 =8.4 Hz, 2H), 7.293 (t, J=8.4 Hz, 2H), 7.091 (t, J=7.5 Hz, 1H), 5.375 (d, J=8.4 Hz, 1H), 4.4 (m, 1H), 4.306 (m, 2H), 3.302 (s, 3H), 2.095-1.750 (m, 4H), 1.446 (s, 9H) ppm.
[0175] 13 C-NMR (300 MHz, CDCl 3 ): δ 170.03, 156.15, 137.63, 128.93, 124.41, 119.83, 69.18, 53.67, 37.46, 28.84, 28.28, 25.34 ppm.
[0176] MS: Positive mode [M+Na] + =409.
[0177] MS: Negative mode [M+2H 2 O−H − ]=421.
Example 4
Preparation of Intermediate [9a]: tert-butyl-2-oxo-1-phenylpiperidin-3-ylcarbamate
[0178]
[0179] Under inert atmosphere, LDA (1.04 mmol, 2 eq) was added to a solution of compound [8a] (0.200 g, 0.52 mmol) in anhydrous THF (5 ml) at 0° C. The solution was stirred for 2.5 h, warming to room temperature. After then, the crude was evaporated to dryness, and purified over Al 2 O 3 using Hexane/AcOEt from 70/30 to 50/50 as the eluant, yielding 0.09 g (60%) of the desired product [9a] and 0.60 g (40%) of the by-product [10a].
[0180] 1 H-NMR (400 MHz, CDCl 3 ): δ 7.39 (t, J=7.6 Hz, 2H Ar ), 7.25 (m, 3H Ar ), 5.5 (br, 1H, NHBoc), 4.26 (m, 1H, C H NHBoc), 3.71 (m, 2H, —CHCH 2 CH 2 C H 2 —), 2.61 (m, 1H, CHC H 2 CH 2 CH 2 —), 2.04 (m, 2H, —CHCH 2 C H 2 CH 2 —), 1.71 (m, 1H, CHC H 2 CH 2 CH 12 —), 1.46 (s, 9H, t Bu) ppm.
[0181] 13 C-NMR (400 MHz, CDCl 3 ): δ 169.94 (CONH), 155.94 (OCONH), 142.47 (C q , C Ar ), 129.15 (CH, C Ar ), 126.81 (CH, C Ar ), 125.64 (CH, C Ar ), 79.622 (C q , t Bu), 51.90 (— C HCH 2 CH 2 CH 2 —), 50.14 (—CHCH 2 CH 2 C H 2 —), 28.36 (CH 3 , t Bu), 27.39 (—CH C H 2 CH 2 CH 2 —), 21.14 ppm (—CHCH 2 C H 2 CH 2 —).
[0182] MS: Positive mode [M+H] + =291, [M+Na] + =313.
Example 5
Preparation of Intermediate [10a]: Tert-butyl-2-(phenylcarbamoyl)-pyrrolidine-1-carboxylate
[0183]
[0184] Under inert atmosphere, t BuOK (0.070 g, 0.65 mmol) was added to a solution of compound [8a] (0.250 g, 0.65 mmol) in anhydrous THF (5.8 ml). The reaction mixture was heated up to 50° C. during 1 h. After then, the crude was evaporated to dryness, and purified over SiO 2 using Hexane/AcOEt 50/50 as the eluant, yielding 0.183 g (97%) of the desired product [10a].
[0185] 1 H-NMR (300 MHz, CDCl 3 ): δ 9.5 (br, NHPhe), 7.51 (dd, J 1 =8.9 Hz, J 2 =1.2 Hz, 2H Ar ), 7.31 (t, J=7.8 Hz, 2H Ar ), 7.08 (t, J=7.2 Hz, 1H Ar ), 4.4 (br, 1H, CH), 3.4 (br, 2H, CH 2 ), 1.93 (m, 2H, CH 2 ), 1.49 (s, 9H, t Bu), 1.49 (s, 2H, CH 2 ) ppm.
[0186] MS: Positive mode [M+H] + =291, [M+Na] + =313.
[0187] MS: Negative mode [M−H] − =289, [M+2H 2 O−H] − =325.
Example 6
Preparation of Intermediate [11a]
[0188]
[0189] To a stirred solution of [9a] (0.08 g, 0.28 mmol) in 1.5 ml of CH 2 Cl 2 was added 0.50 ml of trifluoroacetic acid at room temperature, and the mixture was sealed and stirred for 0.5 h. After then, the crude was evaporated to dryness, yielding an orange oily residue of the organic salt [11a], which was precipitated using i Pr 2 O. The remaining solid was used without further purification.
Example 7
Preparation of Intermediate [12a]
[0190]
[0191] To a stirred solution of [10a] (0.90 g, 3.11 mmol) in 13 ml of CH 2 Cl 2 was added 5.5 ml of trifluoroacetic acid at room temperature, and the mixture was sealed and stirred for 1 h. After then, the crude was evaporated to dryness, yielding an orange oily residue of the organic salt [12a], which was used without further purification.
Example 8
Preparation of N-(2-oxo-1-phenylpiperidin-3-yl)benzenesulfonamide
[0192]
[0193] Under inert atmosphere, to a stirred solution of compound [12a] (0.093 g, 0.29 mmol) in 1 ml anhydrous DMF at 0° C. was added anhydrous Et 3 N (0.15 ml, 1.04 mmol). This mixture was stirred for 5 min, and then PhSO 2 Cl (0.06 ml, 0.44 mmol) was added at 0° C. The reaction was stirred for 2 h at this temperature. Then, the solvent was removed and the crude was chromatographically purified over SiO 2 using Hexane/AcOEt 50/50 as the eluant, yielding 0.057 g (63%) of the desired product.
[0194] 1 H-NMR (300 MHz, CDCl 3 ): δ 7.92 (dd, J 1 =8.1 Hz, J 2 =1.5 Hz, 2H Ar ), 7.6-7.48 (m, 3H Ar ), 7.37 (dd, J 1 =7.8 Hz, J 2 =7.2 Hz, 2H Ar ), 7.26 (ft, J r =8.1 Hz, J 2 =˜1 Hz, 1H Ar ), 7.16 (dd, J 1 =8.1 Hz, J 2 =1.5 Hz, 1H Ar ), ˜6 (s, 1H, NHSO 2 ), 3.8-3.54 (mc, 3H, 1×C H CH 2 CH 2 CH 2 —N+2×CHCH 2 C H 2 CH 2 —N), 2.61 (m, 1H, —CHC H 2 CH 2 CH 2 —N), 2.1-1.8 (mc, 3H, 1×C H CH 2 CH 2 CH 2 —N+2×—CHCH 2 C H 2 CH 2 —N) ppm.
[0195] MS: Positive mode [M+H] + =331, [M+Na] + =353.
Example 9
Preparation of N-(2-oxo-1-phenylpiperidin-3-yl)naphthalene-2-sulfonamide
[0196]
[0197] Following a procedure analogous to that described in Example 8, the title compound was obtained as a white solid in 62% yield.
[0198] MS: Positive mode [M+H] + =380, [M+Na] + =403.
Example 10
Preparation of N-(2-oxo-1-phenylpiperidin-3-yl)quinoline-8-sulfonamide
[0199]
[0200] Following a procedure analogous to that described in Example 8, the title compound was obtained as a white solid in 63% yield.
[0201] MS: Positive mode [M+H] + =382, [M+Na] + =404.
Example 11
Preparation of 4-Chloro-N-(2-oxo-1-phenylpiperidin-3-yl)benzene-sulfonamide
[0202]
[0203] Following a procedure analogous to that described in Example 8, the title compound was obtained as grey oil in 90% yield.
[0204] MS: Positive mode [M+H] + =365, [M+Na] + =387.
Example 12
Preparation of 5-(Dimethylamino)-N-(2-oxo-1-phenylpiperidin-3-yl)-naphthalene-1-sulfonamide
[0205]
[0206] Following a procedure analogous to that described in Example 8, the title compound was obtained as yellow oil in 80% yield.
[0207] MS: Positive mode: [M+H] + =424, [M+Na] + =446.
Example 13
Preparation of 5-Chloro-N-(2-oxo-1-phenylpiperidin-3-yl)thiophene-2-sulfonamide
[0208]
[0209] Following a procedure analogous to that described in Example 8, the title compound was obtained as white oil in 80% yield.
[0210] MS: Positive mode [M+H] + =371, [M+Na] + =393.
Example 14
Preparation of (E)-N-(2-oxo-1-phenylpiperidin-3-yl)-2-phenylethene-sulfonamide
[0211]
[0212] Following a procedure analogous to that described in Example 1, the title compound was obtained as a white solid in 71% yield.
[0213] MS: Positive mode [M+H] + =357, [M+Na]+=379.
Example 15
Preparation of N-benzyl-N-(2-oxo-1-phenylpiperidin-3-yl)-benzenesulfonamide
[0214]
[0215] Under inert atmosphere, to a stirred solution of NaH (2.5 mg, 0.05 mmol) in 0.10 ml anhydrous DMF at 0° C., was added a solution of compound of Example 8 (0.02 g, 0.05 mmol) in 0.20 ml anhydrous DMF. After 1.5 h at 0° C., benzyl bromide (7 μl, 0.05 mmol) was added to the reaction mixture. This mixture was stirred for 2 h, and then solvent was completely removed. The crude was chromatographically purified over SiO 2 using Hexane/AcOEt 50/50 as the eluant, yielding 0.016 g (71%, purity 92%) of the desired product.
[0216] 1 H-NMR (300 MHz, CDCl 3 ): δ 7.92 (dd, J 1 =8.1 Hz, J 2 =1.5 Hz, 2H Ar ), 7.6-7.48 (m, 3H Ar ), 7.37 (dd, J 1 =7.8 Hz, J 2 =7.2 Hz, 4H Ar ), 7.26 (tt, J 1 =8.1 Hz, J 2 =˜1 Hz, 2H Ar ), 7.16 (dd, J 1 =8.1 Hz, J 2 =1.5 Hz, 4H Ar ), 4.42 (sa, 2H, CH 2 Ph), 3.8-3.54 (mc, 3H, 1×C H CH 2 CH 2 CH 2 —N+2×CHCH 2 CH 2 C H 2 —N), 2.61 (m, 1H, —CHC H 2 CH 2 CH 2 —N), 2.1-1.8 (mc, 3H, 1×C H CH 2 CH 2 CH 2 —N+2×—CHCH 2 C H 2 CH 2 —N) ppm.
Example 16
Preparation of benzyl 4-(tert-butoxycarbonylamino)-5-oxo-5-(N-(2-oxo-1-phenylpiperidin-3-yl)phenylsulfonamido)pentanoate
[0217]
[0000] Step 1: Under inert atmosphere, to a stirred solution of NaH (3 mg, 0.07 mmol) in 0.10 ml anhydrous DMF at 0° C., was added a solution of compound of Example 8 (0.022 g, 0.06 mmol) in 0.20 ml anhydrous DMF. The temperature was maintained during 1.5 h.
Step 2: Under inert atmosphere in another reaction vessel, N,N′-Diisopropyl carbodiimide (12 μl, 0.08 mmol) was added to a solution of Boc-L-Glutamic acid-5-benzyl ester (0.022 g, 0.065 mmol) in 0.20 ml anhydrous DMF at room temperature. The temperature was maintained during 1.5 h.
Step 3: After 1.5 h, the reaction mixture of step 1 was added to reaction the reaction mixture of step 2 at room temperature, and was stirred during 6 h. Then solvent was completely removed. The crude was chromatographically purified over Al 2 O 3 using Hexane/AcOEt 25/75 as the eluant, yielding 0.025 g (60%, purity 93%) of the desired product.
[0218] 1 H-NMR (300 MHz, CDCl 3 ): δ 7.92 (dd, J 1 =8.1 Hz, J 2 =1.5 Hz, 2H Ar ), 7.6-7.48 (m, 3H Ar ), 7.37 (dd, J 1 =7.8 Hz, J 2 =7.2 Hz, 2H Ar ), 7.26 (tt, J 1 =8.1 Hz, J 2 =˜1 Hz, 1H Ar ), ˜7.20 (mc, 7H, 7×H Ar ), 5.35 (d, 1H, J=7.8 Hz, CHN H Boc), 5.04 (d, 2H, J=2.6 Hz, BnOC H 2 ), 4.26 (sa, 1H, CH 2 C H NHBoc), 3.8-3.54 (mc, 3H, 1×CHCH 2 CH 2 CH 2 —N+2×CHCH 2 CH 2 C H 2 —N), 2.2-1.8 (mc, 8H), 1.40 (s, 9H, NHCO 2 C(C H 3 ) 3 ) ppm. | Novel compounds are continually sought after to treat and prevent diseases and disorders. The invention relates to N-(2-oxo-1-phenylpiperidin-3-yl)sulfonamides useful for being biologically and pharmacologically screened, and to contribute to the exploration and identification of new lead molecules that are capable of modulating the functional activity of a biological target. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an endoscope with a liquid and gas supply apparatus that supplies liquid and gas such as water and air, to the tip of the endoscope.
2. Description of the Related Art
A liquid and gas supply apparatus, which has a tank and pump, is usually incorporated in a light source apparatus for a fiber-scope or an electronic endoscope system including a video-scope with an image sensor and a video-processor. In the video-scope/fiber-scope, a liquid (water) tube and a gas (air) tube are provided. The tank is spatially connected to the liquid supplying tube and the pump is spatially connected to the gas supplying tube. Generally, water is stored in the tank, whereas the pump takes in and compresses flesh air and sends the compressed air to the tip.
To wash an objective lens provided in the point of the fiber-scope/video-scope, or to remove obstructions on an observed portion, the air or water is discharged from the tip of the fiber-scope/video-scope. When supplying the air, the compressed air flows in the air tube and is then discharged from the tip of the fiber-scope/video-scope. On the other hand, when supplying the water, the compressed air is directed to the inside of the tank, where the water surface is pressed due to the pressure of the compressed gas. Consequently, the water in the tank is pumped out, and flows in the water supplying tube so that the water is discharged from the tip of the fiber-scope/video-scope.
Further, medicinal liquid for inspecting the diseased portion, nitrogen for expanding the inside of the digestive organ, and oxygen for the bronchial tubes are dischargeable via the water supplying tube or the air supplying tube.
In the case of the conventional construction of the liquid and gas supply apparatus, when the tank inclines, water can flow through the air supplying tube and can be unexpectedly discharged from the tip, hence the water is not discharged properly. Especially, the conventional liquid and gas supply apparatus mounted on a desk or table is not suitable for a portable endoscope having an internal light source, because the portablity is reduced.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide a liquid and gas supply apparatus that is capable of preventing unexpected discharge of liquid, and provide a portable endoscope with the liquid and gas supply apparatus.
A liquid and gas supply apparatus according to the present invention is applied to an endoscope, and supplies liquid and gas to a liquid supplying tube and a gas supplying tube respectively. The liquid supplying tube and the gas supplying tube are provided in an endoscope (a fiber-scope or a video-scope with an image sensor). The liquid and gas supply apparatus has a pump, a tank, a first coupling tube, a divergent tube, a balloon, a second coupling tube, and a gas direction controller. The pump pumps the gas, and the tank stores the liquid. The first coupling tube spatially connects the pump with the gas supplying tube. The divergent tube diverges from the first coupling tube and extends toward the inside of the tank. The balloon is spatially connected to the divergent tube and is expandable and shrinkable in the tank. The second coupling tube spatially connects the inside of the tank with the liquid supplying tube such that the liquid in the tank flows in the second coupling tube. The gas direction controller selectively directs the gas discharged from the pump to either the gas supplying tube or the divergent tube. For example, a switch button for performing the gas-supply and the liquid-supply is provided on the endoscope, and a flow-controlling member (for example, a valve) that selectively directs the gas to the gas supplying tube or the divergent tube, is connected to the switch button.
In the present invention, the liquid is stored outside the balloon, and the balloon is constructed such that the liquid outside the balloon does not penetrate to the balloon. The tank includes a sealing member that hermetically seals the tank except for the second coupling tube and the divergent tube. When the gas is supplied, the gas flows in the first coupling tube and the gas supplying tube so that the gas is discharged from the tip of the endoscope. On the other hand, when the liquid is supplied, the gas is directed to the inside of the balloon via the divergent tube by the gas direction controller. The balloon expands due to the input of gas, and the liquid in the tank is pressed because the tank is sealed hermetically. Consequently, the liquid flows in the second coupling tube and is discharged from the tip of the endoscope. Since the liquid does not pass through the balloon, the liquid does not flow into the first coupling tube and the gas supplying tube. Thus, the liquid is not erratically discharged from the tip of the endoscope.
For example, the gas is air and the liquid is water. In this case, preferably, the pump takes in flesh air and discharges compressed air. The compressed air directed to the balloon to expand the balloon. The balloon is expandable and shrinkable. For example, the balloon is composed of a rubber elastic member.
A liquid and gas supply apparatus according to another aspect of the present invention has a pump, a tank, a first coupling tube, a divergent tube, a balloon, a second coupling tube, and a gas direction controller. The pump pumps the gas, and the tank stores the liquid. The first coupling tube spatially connects the pump with the gas supplying tube. The divergent tube diverges from the first coupling tube and extends toward an inside of the tank. The second coupling tube spatially connects the inside of the tank with the liquid supplying tube. The balloon is spatially connected to the second coupling tube and is expandable and shrinkable in the tank. The gas direction controller selectively directs the gas discharged from the pump to one of the gas supplying tube and the divergent tube. The tank includes a sealing member that hermetically seals the tank except for the second coupling tube and the divergent tube. In the present invention, the liquid is stored inside the balloon. When the gas is supplied, the gas flows in the first coupling tube and the gas supplying tube so that the gas is discharged from the tip of the endoscope. On the other hand, when the liquid is supplied, the gas is directed to the inside of the balloon via the divergent tube by the gas direction controller. The balloon shrinks due to the increased gas-pressure, and the balloon is pressed because the tank is sealed hermetically. Consequently, the liquid flows in the second coupling tube and is discharged from the tip of the endoscope.
A portable endoscope according to another aspect of the present invention has a gas supplying tube that transmits gas to discharge the gas from a tip of the endoscope, a liquid supplying tube that transmits liquid to discharge the liquid from the tip of the endoscope, a pump that pumps the gas, a tank that stores the liquid, a first coupling tube that spatially connects the pump with the gas supplying tube, a divergent tube that diverges from the first coupling tube and extends toward an inside of the tank, a balloon that is spatially connected to the divergent tube and is expandable and shrinkable in the tank, a second coupling tube that spatially connects the inside of the tank with the liquid supplying tube such that the liquid in the tank flows in the second coupling tube, and a gas direction controller that selectively directs the gas discharged from the pump to one of the gas supplying tube and the divergent tube. The liquid is stored outside the balloon. The tank includes a sealing member that hermetically seals the tank except for the second coupling tube and the divergent tube.
A portable endoscope according to another aspect of the present invention has a gas supplying tube that transmits gas to discharge the gas from a tip of the endoscope, a liquid supplying tube that transmits liquid to discharge the liquid from the tip of the endoscope, a pump that pumps the gas, a tank that stores the liquid, a first coupling tube that spatially connects the pump with the gas supplying tube, a divergent tube that diverges from the first coupling tube and extends toward an inside of the tank, a second coupling tube that spatially connects the inside of the tank with the liquid supplying tube, a balloon that is spatially connected to the second coupling tube and is expandable and shrinkable in the tank, a gas direction controller that selectively directs the gas discharged from the pump to one of the gas supplying tube and the divergent tube. The liquid is stored inside the balloon, and the tank includes a sealing member that hermetically seals the tank except for the second coupling tube and the divergent tube.
A liquid and gas supply apparatus according to another aspect of the present invention has a container that stores liquid, a space divider that divides an inside space of the container into a first space for storing the liquid and a second space such that one of the first space and the second space expands while the other shrinks, a gas transmitting tube that extends to the second space, a liquid transmitting tube that spatially connects the first space with the liquid supplying tube, and a liquid and gas supplier that supplies the gas to the gas supplying tube, and supplies the liquid in the first space to the liquid supplying tube by supplying the gas to the second space and expanding the second space.
A portable endoscope according to another aspect of the present invention has a gas supplying tube that transmits gas to discharge the gas from a tip of the endoscope, a liquid supplying tube that transmits liquid to discharge the liquid from the point of the endoscope, a container that stores liquid, a space divider that divides an inside space of the container into a first space for storing the liquid and a second space such that one of the first space and the second space expands while the other shrinks, a gas transmitting tube that extends to the second space, a liquid transmitting tube that spatially connects the first space with the liquid supplying tube, and a liquid and gas supplier that supplies the gas to the gas supplying tube, and supplies the liquid in the first space to the liquid supplying tube by supplying the gas to the second space and expanding the second space.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood from the description of the preferred embodiment of the invention set fourth below together with the accompanying drawings, in which:
FIG. 1 is a schematic plan view of portable endoscope according to a first embodiment.
FIG. 2 is a view schematically showing an inner construction of the fiber-scope.
FIGS. 3A and 3B are views showing the flow of air and water.
FIGS. 4A and 4B are views showing the flow of air and water according to the second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the preferred embodiments of the present invention are described with reference to the attached drawings.
FIG. 1 is a schematic plan view of a portable endoscope according to the first embodiment.
A fiber-scope 10 is a portable type fiber-scope with an internal light source, and has a tip portion 15 , a bending portion 14 , an inserting portion 16 , an operating portion 12 , an eyepiece 17 , a light source unit 19 , and a connecting arm 18 . Further, the fiber-scope 10 has a water and air supplying apparatus, as described later. When an operation or inspection is started, the inserting portion 16 is inserted into an inner organ, such as the stomach.
A lamp (not shown) for illuminating a subject S is provided in the light source unit 19 . A fiber-optic bundle (not shown) is provided in the fiber-scope 10 and extends from the light source unit 19 to the tip portion 15 . Light radiated from the lamp passes through the fiber-optic bundle and is radiated from the tip portion 15 . Consequently, the subject S is illuminated by the radiated light. Light reflected on the subject S passes through an objective lens (not shown) provided in the tip portion 15 , and reaches an incident surface of an image fiber-optic bundle (not shown). Thus, the subject image is formed on the incident surface. The image fiber-optic bundle is provided for optically transmitting the subject image and extends from the tip portion 15 to the eyepiece 17 . The optically transmitted subject image is formed at the eyepiece, thus the operator can observe the subject S via the eyepiece 17 .
A lever (not shown) for bending the bending portion 15 , and a water and air supplying switch button 13 A, and a lamp switch button 13 B are provided on the operating portion 12 . The water and air supplying switch button 13 A is operated to supply the water and the air, as described later. A tank 30 , in which water is stored, is detachably attached to the connecting arm 18 extending from the operating portion 12 .
FIG. 2 is a view schematically showing an inner construction of the fiber-scope 10 .
To wash the objective lens and remove a dart on the subject S, water and air supplying tubes 26 are provided in the fiber-scope 10 . The water and air supplying tubes 26 has an air supplying tube 26 E for transmitting air, and a liquid supplying tube 26 D for transmitting water. They extend from the tip portion 15 to the water and air supplying switch button 13 A. A pump 34 is provided in the operating portion 12 , and a coupling tube 26 B is provided between the pump 34 and the water and air supplying switch button 13 A to spatially connect the pump 34 with the air supplying tube 26 E. A divergent tube 26 A, which diverges from the coupling tube 26 B, extends to the inside of the tank 30 , and a balloon 31 is attached to the point of the divergent tube 26 A. On the other hand, a coupling tube 26 C is provided between the tank 30 and the water and air supplying switch button 13 A to spatially connect the inside of the tank 30 with the water supplying tube 26 D.
The pump 34 takes in flesh air and discharges compressed air, and the an intake tube 35 extends to a hole (not shown) formed on an outer surface of the operating portion 12 . A discharging outlet 37 , from which the compressed air is discharged, is spatially connected to the coupling tube 26 B and the divergent tube 26 A. When the pump 34 operates, the compressed air flows in the coupling tube 26 B toward the water and air supplying switch button 13 A. Electric power is supplied from a battery 36 to the pump 34 . When a pump button (not shown) is operated, a pump switch 39 provided between the battery 36 and the pump 34 is turned ON, thus the pump 34 operates.
A valve 33 is connected to the water and air supplying switch button 13 A. When the water and air supplying switch button 13 A is not covered by the thumb of the operator, the valve 33 intercepts, or closes the spatial connection between the coupling tube 26 B and the air supplying tube 26 E, and discharges the compressed air, transmitted from the pump 34 , from the top portion 13 T of the water and air supplying switch button 13 A. In other words, the compressed air is not supplied to the air supplying tube 26 E, hence air is not supplied. Further, the valve 33 closes the spatial connection between the water supplying tube 26 D and the water coupling tube 26 C, hence water is not supplied.
When supplying air, the thumb of the operator is placed on the top portion 13 T of the water and air supplying switch button 13 A. The position of the valve 33 is shifted toward the opposite side of the top portion 13 A by the backflow of air, so that the coupling tube 26 B is spatially connected to the air supplying tube 26 E. Thus, the compressed air is fed from the pump 34 to the air supplying tube 26 E and is discharged from the tip portion 15 .
When supplying water, the water and air supplying switch button 13 A is pressed by the thumb of the operator. The position of the valve 33 is further shifted by the pressing, which spatially closes the coupling tube 26 B and the air supplying tube 26 E, and spatially connects the coupling tube 26 C and the water supplying tube 26 D. Consequently, as described later, the compressed air from the pump 34 flows toward the tank 30 , and the water W in the tank 30 is displaced. The displaced water W flows in the coupling tube 26 C, the water and air supplying switch button 13 A, and the water supplying tube 26 D, and is then discharged from the tip portion 15 .
Note that, the construction of the water and air supplying switch button 13 A having the valve 33 , described above, is well known in the prior art.
FIGS. 3A and 3B are views showing a flow of air and water.
The cylindrical tank 30 has a storing portion 30 A, a cover 30 B and connecting portion 32 , the connecting portion 32 being attached at the upper surface of the cover 30 B. The coupling tube 26 C and the divergent tube 26 A respectively go through the connecting portion 32 and the cover 30 B, and extend to the inside of the tank 30 . The connecting portion 32 has a male screw configuration and is thread into the connecting arm 18 . Namely, the tank 30 is detached from the connecting arm 18 by rotating the tank 30 . The cover 30 B is attached to the storing portion 30 A such that the cover 30 B interposes the ring-shaped upper edge 30 C of the storing portion 30 A. The storing portion 30 A is detachable from the cover 30 B by pulling the storing portion 30 A downward, namely, away from the connecting arm 18 . When adding the water W, the storing portion 30 A is detached form the cover 30 B. The cover 30 B hermetically seals the inside of the storing portion 30 A. While the storing portion 30 A is attached to the cover 30 B, the air and water W in the tank 30 do not leak out and no gas or liquid penetrates into the tank 30 , except through the coupling tube 26 C and the divergent tube 26 A.
In this embodiment, the balloon 31 is composed of a rubber elastic compound, which is impervious to liquid. When the compressed air is fed from the pump 34 to the balloon 31 , the balloon 31 expands, namely, inside space of the balloon 31 increases. On the other hand, when compressed air is not fed, the balloon 31 is maintained in the shrunk situation. In the tank 30 , the water W is stored outside the balloon 31 , and the amount of water W is a half of the capacity of the tank 30 . Hereinafter, the space, in which the water W is stored, is designated as the “first space”, and the space in the balloon 31 is designated as the “second space”.
When supplying the air, the compressed air discharged from the pump 34 flows in the coupling tube 26 B and is directed to the water and air supplying switch button 13 A and the air supplying tube 26 E. Therefore, the water W does not flow out from the tank 30 and the balloon 31 does not expand (See FIG. 3 A).
When the water and air supplying switch button 13 A is pressed to supply the water, the compressed air discharged from the pump 34 flows in the divergent tube 26 A, so that the balloon 31 expands. The liquid surface LS of the water W tends to rise because of the expansion of the balloon 31 . However, since the tank 30 is sealed hermetically by the cover 30 B, air pressure in the first space S 1 increases, which presses the liquid surface LS of the water W downward. Consequently, the water W flows in the coupling tube 26 C and is discharged from the tip portion 15 via the water and air supplying switch button 13 A and the water supplying tube 26 D (See FIG. 3 B). The amount of the water W, which is supplied, corresponds to expanded volume of the balloon 31 . When the pump 34 is suspended after the balloon 31 expands, the balloon 31 shrinks and pressure in the first space S 1 decreases. Consequently, the situation in the tank 30 returns to the situation before the water-supply.
In this way, in this embodiment, the balloon 31 is provided in the tank 30 and is connected to the tip of the coupling tube 26 B. The water W is stored in the first space S 1 and the cover 30 B seals hermetically the storing portion 30 A. When the compressed air is fed to the balloon 31 , the water W is forced out by pressure and flows in the coupling tube 26 C because of the expansion of the balloon 31 . In this embodiment, the path for the water and the path for the air are perfectly separate. Therefore, although the tank 30 inclines while the endoscope 10 is being operated, the water W is not erratically discharged from the tip portion 15 via the air supplying tube 26 E.
Since the balloon 31 shrinks when the pump 34 is suspended, the water W is not instantaneously discharged when the storing portion 30 A is detached from the cover 30 B.
The balloon 31 may be composed of material other than rubber elastic, if expandable and shrinkable. The coupling tube 26 C may be arranged adjacent to the storing portion 30 A so that the coupling tube 26 C dose not interfere with the expanded balloon 31 .
In this embodiment, the water-supply and the air-supply are independently controlled by using the water and air supplying switch button 13 A with the valve 33 . However, other construction may be applied. For example, the flow of the compressed air may be controlled by a solenoid valve.
As for the construction of the tank 30 , a member other than the cover 30 B can be used to seal the inside of the tank 30 hermetically. Further, the tank 30 may be attached to the connecting arm 18 such that the water surface LS of the water W is perpendicular to a line passing through the tip portion 15 and eyepiece 17 .
FIGS. 4A and 4B are views showing the flow of water and air according to a second embodiment. The second embodiment is different from the first embodiment in that water is stored in a balloon.
As shown in FIG. 4A, in the second embodiment, the balloon 31 is attached to the coupling tube 26 ′C (not the divergent tube), and the divergent tube 26 ′A extends to the bottom of the tank 30 . The water W is stored in the space inside of the balloon 31 (in the second embodiment, designated as the “first space”), and is not stored in the space outside of the balloon 31 (in the second embodiment, designated as the “second space”).
When supplying the air, the compressed air discharged from the pump 34 directly flows in the coupling tube 26 B and is discharged from the tip portion 15 . On the other hand, when supplying the water, the compressed air flows in the divergent tube 26 ′A and is directed to the inside of the tank 30 . The pressure in the second space S 2 increases because of the inflow of the compressed air. The balloon 31 shrinks as the second space S 2 expands, so that the water W flows through the coupling tube 26 ′C and is discharged from the tip portion 15 .
In the first and second embodiments, the water and air supplying apparatus is incorporated in the portable fiber-scope 10 , however, the water and air supplying apparatus may be applied to a conventional light source or electronic endoscope mounted on a desk or table.
As for the air-supply, nitrogen or oxygen may be discharged from the tip portion 15 in place of air. In this case, a nitrogen cylinder or oxygen cylinder may be connected to the inlet of the pump 34 . Further, as for the water-supply, medicinal liquid maybe stored in the tank 30 in place of water.
Finally, it will be understood by those skilled in the art that the foregoing description is of preferred embodiments of the device, and that various changes and modifications may be made to the present invention without departing from the spirit and scope thereof.
The present disclosure relates to subject matters contained in Japanese Patent Application No. 2001-243343 (filed on Aug. 10, 2001) which is expressly incorporated herein, by reference, in its entirety. | A portable endoscope has a pump, a tank that stores liquid, a first coupling tube that spatially connects the pump with a gas supplying tube, a divergent tube that diverges from the first coupling tube and extends toward an inside of the tank, a balloon that is spatially connected to the divergent tube and is expandable and shrinkable in the tank, a second coupling tube that spatially connects the inside of the tank with a liquid supplying tube, and a gas direction controller that selectively directs the gas discharged from the pump to one of the gas supplying tube and the divergent tube. The liquid is stored outside of the balloon. The tank includes a sealing member that hermetically seals the tank. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to fuel cell systems, and more particularly to humidifying charge air delivered to a fuel cell stack.
BACKGROUND OF THE INVENTION
[0002] Fuel cell systems are increasingly being used as a power source in a wide variety of applications. Fuel cell propulsion systems have also been proposed for use in vehicles as a replacement for internal combustion engines. The fuel cells generate electricity that is used to charge batteries and/or to power an electric motor. A solid-polymer-electrolyte fuel cell includes a membrane that is sandwiched between an anode and a cathode. To produce electricity through an electrochemical reaction, a fuel, commonly hydrogen (H 2 ), but also either methane (CH 4 ) or methanol (CH 3 OH), is supplied to the anode and an oxidant, such as oxygen (O 2 ) is supplied to the cathode. The source of the oxygen is commonly air.
[0003] In a first half-cell reaction, dissociation of the hydrogen (H 2 ) at the anode generates hydrogen protons (H + ) and electrons (e − ). The membrane is proton conductive and dielectric. As a result, the protons are transported through the membrane. The electrons flow through an electrical load (such as the batteries or the electric motor) that is connected across the membrane. In a second half-cell reaction, oxygen (O 2 ) at the cathode reacts with protons (H + ), and electrons (e − ) are taken up to form water (H 2 O).
[0004] The relative humidity of the oxidant impacts durability and efficiency of the fuel cell system. Conventional strategies have been developed to humidify the oxidant flowing to the fuel cell. These strategies, however, present certain disadvantages. One disadvantage is that the achievable humidification level is limited. Other disadvantages include low durability, higher cost and increased space requirements.
SUMMARY OF THE INVENTION
[0005] Accordingly, the present invention provides a fuel cell system. The fuel cell system includes a fuel cell stack that receives a cathode feed gas and has an exhaust stream and a heat transfer stream flowing therefrom. A charge-air heat exchanger enables heat transfer between the heat transfer stream and the cathode feed gas to adjust a feed gas temperature. The charge-air heat exchanger also enables heat transfer between the heat transfer stream and a liquid water to vaporize the liquid water providing water vapor. The water vapor humidifies the cathode feed gas. Preferably, the source of liquid water is a water condensate originating from within the fuel cell system. In one aspect, the heat transfer stream includes a fluid operable to heat and cool as needed. An important feature is cooling and therefore, the heat transfer stream is referred to as coolant for simplicity. It is appreciated, however, that it is not limited to cooling as it may also heat.
[0006] In one feature, the fuel cell system further includes a condenser that condenses water vapor in the exhaust stream.
[0007] In another feature, the fuel cell system includes an injector that injects the water condensate into the cathode feed gas. Preferably, the injector forms a part of the charge-air heat exchanger or is adjacent the charge-air heat exchanger.
[0008] In still another feature, the fuel cell system further includes a compressor that compresses the cathode feed gas. The compressor receives a portion of the water condensate to humidify the cathode feed gas within the compressor. The compressor comprises an injector that injects the water condensate into the cathode feed gas. The water condensate is vaporized within the compressor during a compression process.
[0009] In yet another feature, a portion of the water condensate is injected into the fuel cell stack to humidify the cathode feed gas within the fuel cell stack.
[0010] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0012] FIG. 1 is a fuel cell system including charge air humidification according to the present invention;
[0013] FIG. 2 is an alternative fuel cell system including charge air humidification according to the present invention; and
[0014] FIG. 3 is another alternative fuel cell system including charge air humidification according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
[0016] Referring now to FIG. 1 , a fuel cell system 10 is shown. The fuel cell system 10 includes a fuel cell stack 12 , a coolant system 14 , a charge-air heat exchanger 16 and a compressor 18 . The coolant system 14 maintains the operating temperature of the fuel cell stack 12 at an appropriate level. Additionally, the coolant system 14 adjusts the temperature of fluids at various points in the fuel cell system 10 as explained in further detail below. The compressor 18 compresses oxidant that is supplied to the fuel cell stack 12 . More specifically, the oxidant is supplied as a cathode feed gas or charge air to a cathode side (not shown) of the fuel cell stack 12 . The cathode feed gas catalytically reacts with a hydrogen-rich reformate supplied to an anode side (not shown) of the fuel cell stack 12 . The oxidant is oxygen-rich air supplied by the compressor 18 and charge-air heat exchanger 16 at an appropriate operating state (i.e., temperature and pressure). The oxidant reacts with the hydrogen-rich reformate to produce electrical power and an exhaust stream.
[0017] The exhaust stream is made up of reaction products including water (H 2 O) vapor and a small amount of liquid H 2 O depending on the operating strategy of the fuel cell stack 12 . The H 2 O vapor condenses as it travels through an exhaust conduit 20 to provide an H 2 O condensate. The exhaust conduit 20 can be configured to maximize the surface area over which the exhaust stream passes to enable condensation of the H 2 O vapor. Alternatively, a condenser 22 can be included to condense the H 2 O vapor to provide the H 2 O condensate. It is also anticipated that the source of H 2 O can be provided from a means other than the exhaust stream. For example, a separate water storage tank (not shown) can be used to supply liquid H 2 O.
[0018] The coolant system 14 controls coolant flow through the fuel cell system 10 and includes a pump (not shown) and a radiator (not shown) that enables heat transfer to atmosphere. As used herein, the term coolant refers to a heat transfer fluid that is able to cool and heat as needed. For example, in a situation where the coolant is warmer than an adjacent fluid or structure, the coolant serves to heat that adjacent fluid or structure. Similarly, in a situation where the coolant is cooler than an adjacent fluid or structure, the coolant serves to cool that adjacent fluid or structure. Coolant is pumped through the fuel cell stack 12 to cool the fuel cell stack 12 and maintain an operating temperature of the fuel cell stack 12 . The coolant flows from the fuel cell stack 12 , through the charge-air heat exchanger 16 and back to the coolant system 14 . A regulator valve 23 is optionally provided to control the flow rate of coolant to the charge-air heat exchanger 16 . As described in further detail below, the heat of compression and heat transfer from the coolant enables vaporization of the H 2 O condensate. The heat exchanger adjusts the cathode feed gas to an appropriate temperature for reaction in the fuel cell stack 12 .
[0019] The H 2 O condensate and coolant are directed to the charge-air heat exchanger 16 and cooperate to humidify the cathode feed gas. More particularly, an injector or multiple injectors 24 are provided to inject the H 2 O condensate into the cathode feed gas as it flows through the charge-air heat exchanger 16 . The coolant is in heat exchange relationship with the cathode feed gas and injected H 2 O condensate. Preferably, the adiabatic cooling effect occurs whereby the charge air temperature drops and the H 2 O condensate is vaporized to form H 2 O vapor. Additionally, heat transfer occurs from the coolant to the H 2 O condensate, vaporizing the H 2 O condensate. Concurrently, heat transfer occurs from the coolant to the cathode feed gas, reheating the cathode feed gas. As a result, the process in one embodiment is operable essentially at constant temperature and pressure (i.e., state) maintained by the coolant (i.e., working fluid).
[0020] Depending upon the amount of the H 2 O condensate that must be injected to humidify the cathode feed gas to an appropriate level, a multi-stage humidification process is provided in one embodiment. The multi-stage humidification process includes a first stage with an injector 24 for injecting a first volume of the H 2 O condensate into the cathode feed gas. The first volume is vaporized within the cathode feed gas stream in the heat transfer process as described above. A second stage includes a second injector 24 for injecting a second volume of the H 2 O condensate into the partially humidified cathode feed gas. The second volume is vaporized within the cathode feed gas stream in the adiabatic heat transfer process as described above. Two or more stages (e.g., third and fourth stages) can be implemented to achieve the desired humidity level of the cathode feed gas.
[0021] Referring now to FIG. 2 , a fuel cell system 10 ′ is shown and includes humidification of the cathode feed gas within the compressor 18 . More specifically, a portion of the H 2 O condensate is fed to an inlet of the compressor 18 . The compressor includes an injector 26 that injects the H 2 O condensate into the cathode feed gas at the compressor suction side. The compression process generates sufficient heat to vaporize a part of the H 2 O condensate, humidifying the cathode feed gas. Thus, the fuel cell system 10 ′ of FIG. 2 provides for humidification of the cathode feed gas at both the compressor 18 and the charge-air heat exchanger 16 , as described in detail above.
[0022] The proportion of cathode feed gas humidification that occurs within the compressor 18 to that which occurs within the charge-air heat exchanger 16 can be controlled. Due to the limited available heat of compression and dwell time, a smaller portion of humidification can occur within the compressor 18 . As a result, the larger portion of humidification occurs within the charge-air heat exchanger 16 as detailed above. Alternatively, a larger portion of humidification can occur within the compressor 18 . As a result, the smaller portion of humidification occurs within the charge-air heat exchanger 16 . In such a case, the multi-stage humidification process may not be required depending on how much H 2 O condensate must be injected to sufficiently humidify the cathode feed gas.
[0023] Referring now to FIG. 3 , a fuel cell system 10 ″ is shown and includes humidification of the cathode feed gas within the compressor 18 , the cooler 16 and the fuel cell stack 12 . More specifically, a portion of the H 2 O condensate is fed to the compressor 18 for humidifying the cathode feed gas as described above with respect to FIG. 2 . Additionally, a portion of the H 2 O condensate is fed to the fuel cell stack 12 . An injector 28 is provided to inject the H 2 O condensate into the cathode feed gas within the fuel cell stack 12 . Heat transfer occurs to vaporize the H 2 O condensate, humidifying the cathode feed gas within the fuel cell stack 12 . Thus, the fuel cell system 10 ″ of FIG. 3 provides for humidification of the cathode feed gas at the compressor 18 and at the charge-air heat exchanger 16 as described in detail above, as well as within the fuel cell stack 12 itself. As described above with reference to FIG. 2 , the proportion of humidification that occurs within the compressor 18 , the charge-air heat exchanger 16 and the fuel cell stack 12 can vary as design requirements dictate.
[0024] The fuel cell systems of the present invention include several distinct advantages over conventional humidification strategies. One advantage is that overall system durability and efficiency is improved. This is a result of a higher achievable humidification level over conventional systems and a reduced heat load on the cooling system. The reduced heat load is a result of the heat that would otherwise be discharged through the coolant system being used to vaporize the H 2 O condensate within the cooler. As a result, lower system temperatures and a more stream-lined coolant system including a smaller radiator are achieved. Additionally, less liquid H 2 O exits the exhaust of the vehicle.
[0025] The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention. | A fuel cell system includes a fuel cell stack that receives a cathode feed gas and has an exhaust stream and a heat transfer stream flowing therefrom. A charge-air heat exchanger enables heat transfer between the heat transfer stream and the cathode feed gas. The charge-air heat exchanger also enables heat transfer between the heat transfer stream and the cathode feed gas to compensate for the adiabatic cooling effect. Furthermore, the charge-air heat exchanger vaporizes the liquid water to provide water vapor. The water vapor humidifies the cathode feed gas. | 7 |
This application is a continuation of prior co-pending application Ser. No. 693,920 filed Jan. 22, 1985, now abandoned, which is a continuation-in-part of prior co-pending application Ser. No. 646,676 filed Sept. 4, 1984, now abandoned.
BACKGROUND OF THE INVENTION
1. The Field of the Invention
The present invention concerns a system and process for controlling the formation of sheet materials such as paper.
2. State of the Art
Various sheet materials are manufactured by causing the material in a fluid state to flow in a controlled fashion onto a conveyer or the like. For example, sheet plastic is often manufactured by extruding heated plastic through a die onto a conveyer belt. Likewise, paper is often manufacture by causing a slurry of paper pulp to flow from a headbox onto a moving wire. In the manufacture of sheet materials, a thickness-regulating member is normally used to insure that the thickness of the sheet is substantially uniform both in the direction in which the sheet travels and in the direction perpendicular thereto. In the case of paper, the thickness regulating member is called a slice lip and in the case of plastics, the thickness regulating member can be called a die. In either case, the position of the thickness-regulating member is controlled by actuators, which in the case of paper manufacturing include slice rods.
U.S. Pat. No. 3,413,192 teaches a system for controlling a thickness regulating member used in the manufacture of sheet products. According to the patent, a water slurry of fibrous paper stock is fed into a headbox, and the slurry then flows through a slice lip opening slot to be deposited in a continuous web onto a Fourdrinier wire which is continuously moving in a direction away from the headbox. The position of the slice lip is controlled by a plurality of actuators connected to the slice lip and to the headbox and spaced apart from one another along the length of the slice lip.
Further, according to the patent, the pape slurry dries as it travels along the Fourdriner wire and thereafter the paper web is fed between press rolls for removal of additional moisture. The web is then fed through a drier section, and the finished paper web issues from the drier. After the dried paper leaves the drier, a conventional basis weight measuring gauge including a source of nuclear radiation is used to measure the thickness of the web across the width thereof. Information from the measuring gauge is transmitted to a control system which in turn controls the slice actuators to maintain the thickness of the paper being produced according to a predetermined scheme.
One of the shortcomings of the system taught in the patent is that the physical characteristics of the slice lip and the actuators are not explicityly considered. It is believed that this leads to certain inaccuracies in the operation of the system.
OBJECTS OF THE INVENTION
An object of the present invention is to provide a system and process for controlling a thickness regulating member wherein the physical characteristics of the thickness regulating member are taken into consideration prior to using the system to control the manufacture of a sheet material.
Another object of the present invention is to provide a process for controlling the configuration of a thickness regulating member including determining at least one matrix by modeling the thickness-regulating member and actuator system as an elastic system without basing the determination on any of the following parameters: spring constants of the actuators, elastic modulus of the thickness-regulating member, and cross-sectional moment of inertia of the thickness regulating member.
Further objects and advantages of the present invention can be ascertained by reference to the specification and drawings which are offered by way of example and not in limitation of the invention which is defined by the claims and equivalents thereto.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a paper making system according to one embodiment of the present invention.
FIG. 2 is an expanded view of one part of the system shown in FIG. 1.
FIG. 3 is a graph illustrating one mode of operatin of the present embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1, the present embodiment includes a headbox 10 to contain paper pulp. The headbox 10 includes a plurality of control members 12 coupled to a slice lip 14. Below the slice lip 14 is located the slice opening 16 through which the paper pulp is distributed onto a moving Fourdrinier wire 20. In accordance with conventional paper making processes the sheet of paper 22 is processed in a drier 24 and then rolled for shipment onto a reel 26. A scanner 30 is positioned across the sheet 22 near the reel 26. The scanner 30 is conventional and will not be described in detail herein. The scanner has two gauges, a basis weight gauge 32 and a moisture gauge 34, which move back and forth across the moving sheet and simultaneously measure the basis weight and moisture of the sheet. The gauges 32 and 34 produce electrical signals corresponding to the measured property of the sheet, and the electrical signals are transmitted to a controller 36. The controller 36 includes a computer to process information received from the gauges 32 and 34, and the controller also includes means coupled to the control members 12 to control the operation thereof.
FIG. 2 shows details of the control members 12. Each member 12 includes a support tube 40 which is connected to the side of the headbox 10 by mounting brackets 42. A screw jack 44 is coupled to the upper end of the support tube 40, and a know 46 is coupled to the upper end of the screw 44. To the lower end of the screw jack 44 is coupled a slice rod or actuator 45 which includes a heating element, not shown. The slice rod 45 is hollow, and the heating element extends substantially the full length of the interior of slice rod 45. The heating element is a pair of elecrically insulated wires so that when current is applied the wires heat thereby heating the slice rod. A wire pair 51 is coupled to the heating element and extends out of the tube 40 for coupling to a power source.
Each connector 50 has a threaded hole, not shown, formed therein to accept a slice rod 45, and the rods 45 are threaded at their lower ends to permit the rods to be screwed into the connectors 50. Each connector 50 has a mounting member 54 formed on its lower end to cooperate with the slice lip 14.
When electric current is applied to the wires 51, the heating element is heated thus heating the rod 45 so that it expands and becomes longer, thus forcing the slice lip 14 downward. On the other hand, when no current is applied the heating element cools and the rod 45 contracts. For further discussion of the control members 12, see U.S. Pat. No. 4,406,740 titled "Apparatus for Effecting the Fine Adjustment of the Lip of a Headbox of a Paper Making Machine" assigned to Chleq Frote et Cie.
The slice lip 14 extends the length of the headbox and has a substantially flat side which fits flush against the front wall of the headbox 10. The opposing side of the slice lip 14 is curved and has a notch 56 to cooperate with the mounting member 54 so that vertical movements of a connector 50 results in corresponding vertical movement of the portion of the slice lip to which the connector is coupled. Behind the slice lip 14 the front face of the headbox 10 has a slice opening 16 to permit pulp to flow from the headbox onto the wire above a forming board 60. Thus it can be seen that the shape of the lower edge of the slice lip 14 determines the configuration of the flow of pulp from the slice opening 16. That is, if a portion of the slice lip 14 is raised, more pulp will be allowed to flow through the slice opening 16, and if a portion of the slice lip 14 is lowered toward the forming board 60, the slice opening will be correspondingly reduced in height thereby restricting the flow of pulp through the slice opening. Thus, it can be seen that the operation of the slice rods or actuators 45 can be used to control the basis weight of the paper measured by the gauge 32.
We have found that control of the actuators can advantageously be based upon certain information which is predetermined prior to operation of the system.
Prior to operation of the system, two matrices are determined. ##EQU1## n=the number of actuators coupled to the slice lip.
Each of the above matrices is derived by modelling the slice lip as an elastic beam supported by elastic supports and loaded at the actuators. Such systems are well analyzed in mechanical and civil engineering disciplines, and various approximations are well known. For the particular application for headbox slice lip control we have chosen an approximation which is to consider the slice lip as a slender elastic beam, and its deflections small with respect to its other dimensions. This allows approximation of the radius of curvature at any point of the beam as 1/R=y", where y is displacement, and allows expression of the relationship between the moment, M, and the curvature as M=E I y", where E is the modulus of elasticity and I is the moment of inertia. In practice, the slice rods 45 are relatively thin and flexible. This allows for a reasonable assumption that the rods apply forces only, and the torques exerted by the rods are negligible. The behavior of the slice lip segments between two adjacent actuators can be expressed in terms of moments acting at the two ends of each segment. The neighboring ends of two adjacent segments must assure the continuity of the slice lip, and hence the positions and slopes at the neighboring ends must equal each other. This way one can express (n-1) relations, where (n) is the number of rods along the slice lip and where 1 is the distance between rods, as,
1.sub.i M.sub.i +2(1.sub.i +1.sub.i+1)M.sub.i+1 +1.sub.i+1 M.sub.i+2 =(6E I/1.sub.i +1.sub.i+1) (1.sub.i+1 y.sub.i -(1.sub.i +1.sub.i+1 +1.sub.i)y.sub.i+1 +1.sub.i y.sub.i+2)
The moments arise primarily from the forces exerted by the rods and can be expressed in (n-1) equations as,
M.sub.i -M.sub.i-1 =1.sub.1 F.sub.1 +1.sub.2 F.sub.2 +. . . +1.sub.i-1 F.sub.i-1
In equilibrium, all forces acting on the slice lip must add up to zero, expressed as,
F.sub.1 +F.sub.2 +. . . +F.sub.n =0
Since the forces emerge due to the loading of the rods, causing them to deform practically in an elastic manner,
F.sub.i =k.sub.i (z.sub.i -y.sub.i)
The collection of these equations can be solved to express the necessary displacement of the rods (z i ) to result in a slice lip shape (y i ).
Thus it can be seen that the matrices R a , A, P a and D a are based upon the assumptions of equal spacing between the rods; all force on the slice lip is acting at the rods; and all rods are identical. In the event that any or all of these assumptions is not satisfied, different matrices could be computed. However, as a practical matter, we have found that the above-identified matrices would be applicable to most practical cases.
It can also be seen that the matrices are determined without basing the determination on any of the following parameters: spring constants of the slice rods, elastic modulus of the slice lip and cross-sectional moment of inertia of the slice lip.
Once matrices A and R a have been determined then certain physical parameters of the system must be detemined also. In particular, the following must be determined based upon a physical experiments or information from the manufacturer of the equipment.
E, the modulus of elasticity of the slice lip;
I, the cross sectional moment of inertia of the slice lip;
k, the spring constant of the slice rod 45;
l, the distance between slice rods.
Once this information has been determined or computed, the information is fed into the computer of the controller 36. Then the system can be installed in the field and operated according to the following equation: ##EQU2##
In this equation, Z equals a vector of the required slice rod movements Y equals a vector of required displacements of the thickness regulator member at each actuator, J equals the identity matrix and the other variables are as discussed above. In more general terms, the required slice rod movements are a function of the required displacements and physical parameters of the system, i.e.:
Z=f(Y, E, I, k, l)
In some circumstances, it may not be convenient to determine the parameters E, I, k based on data provided by the manufacturer of the hardware. In such cases, an operator in the field can utilzie the following procedure to develop a parameter c, which can be used in place of the parameters identified above. Specifically, with reference to FIG. 3, a series of curves have been developed showing rod number versus displacement of the slice lip when a single rod, for example, rod 10 is moved in one direction. Tests have shown that if the parameter c is a certain value, say C1, and rod 10 is displaced a distance X1 then the slice lip in the area adjacent the rod 10 will be displaced as shown on the curve C1. Likewise, if rod 10 is displaced a distance X2 then the slice lip adjacent the rod 10 will be displaced according to curve C2, and if parameter c has the value C3 and rod 10 is displaced a distance X3 then the slice lip will be displaced according to curve C3. Once the parameter C has been determined, then the following equation can be used to operate the system.
Z=[A].sup.-1 c[Ra]+[J]Y
It should be understood that although one particular type of actuator is taught herein, the present invention is likewise applicable to other types of actuators. For example, plastic extruders and other sheet material processes employing actuators of the type taught herein or actuators which are hydraulically powered or motor driven are appropriate for application of the present invention. | A process is provided for controlling a thickness regulating member such as a slice lip coupled to slice rods. The process includes determining the desired configuration of the slice lip and determing the required slice rod movements based upon physical characteristics of the slice lip and the slice rods. | 3 |
This is a continuation of copending application Ser. No. 07/761,937 filed on Oct. 10, 1991, now U.S. Pat. No. 5,139,130.
FIELD OF THE INVENTION
This invention relates to devices for guiding coins, to different and selectable paths after they have arrived at the device on substantially the same path.
BACKGROUND OF THE INVENTION
The particular device to be described is designed specifically for guiding coins which have been validated by an electronic coin validator to different paths which respectively lead to different storage locations each for a particular denomination of coin. In that situation, the validator will determine the denomination of the coin, and the validator will control the guiding device so that it will deliver that coin to the path which leads to the correct storage location for coins of that denomination.
There is a requirement for different coin denominations to be stored separately, in coin mechanisms which have to give change, for example in vending machines, and in coin mechanisms which have to pay out prizes, for example in gaming machines.
Devices for separating incoming coins onto different paths have generally been referred to as coin sorters and include passive types and active types. In passive coin sorters, such as window sorters, the path of the coins is provided with fixed mechanical features so designed that coins of different denominations, because of their different dimensions, will depart from the path at different points and thereafter will travel to different storage locations. As the number of different denominations to be sorted increases, it becomes more and more difficult to design passive sorters that will operate reliably, and they become undesirably large. In active coin sorters, typically a group of independently solenoid actuated gates is provided which can be switched into different configurations to divert an incoming coin onto anyone of a number of outlet paths. These also tend to become bulky as the number of coin denominations to be sorted increases, and the plurality of actuators required makes them, fairly costly and increases the chance of mechanical or electrical failure.
The present invention aims to provide an active coin sorter which is compact, especially in height, relatively simple in construction, and capable of sorting coins onto a relatively large number of paths.
SUMMARY OF THE INVENTION
The invention provides a device for guiding a coin arriving in an entry of the device to a selected one of a plurality of exits of the device, comprising a movable guide having a plurality of inlets each leading to a common outlet, the guide being movable to position said outlet in register with any selected one of said exits, and said inlets being so arranged that one of them is in a position to admit a coin arriving through said entry irrespective of the position of the guide, whereby said coin is guided from said one inlet via the common outlet to the selected exit.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be more clearly understood, a preferred embodiment will be described, by way of example, with reference to the accompanying diagrammatic drawings in which:
FIGS. 1(a) to (f) show a coin guiding device in accordance with the invention set to respective different positions in order to guide incoming coins to different paths, and
FIG. 2 is a perspective view of components of the device shown in FIG. 1.
DETAILED DESCRIPTION
Referring to FIGS. 1(a) and 2, the device comprises a support plate 2 the upper part 4 of which projects forwardly and is formed with an entry 6 for arriving coins 8.
A plurality of vanes 10 are fixed to the front of the support plate 2 near its lower end and define between them eleven exits of the device in the form of passageways 12. A different number of exits may of course be provided.
The device further includes a generally drum-like rotatable guide 14 having a plurality of (in this case five) inlets 16 each leading to a common outlet 18. Guidance channels 20, 22, 24, 26, and 28 lead into the guide 14 from the respective inlets 16 to the common outlet 18.
The upper ends of the guidance channels are defined by four fixed blades 30, 32, 34 and 36, of which the two inner blades 32 and 34 are the longer and the outer blades 30 and 36 are shorter, in conjunction with the curved wall surfaces 38 and 40 on the main body of the guide 14.
It can be seen from the drawings that the guidance channels 20, 22 and 26, 28 merge with each other below the blades 30 and 36, and that the two merged outer channels thus formed then merge, in turn, with the central guidance channel 24 below the longer blades 32 and 34 so that in effect all channels combine at the common outlet 18.
In the region where adjacent channels merge with each other trailing (that is to say trailing with respect to the direction of coin travel through the device) flaps 42, 44, 46 and 48 are provided, these being freely pivoted at the lower edges of the respective blades 30, 32, 34 and 36.
Referring to FIG. 2, the guide 14 is mounted at the end of the output shaft 50 of a stepper motor 52. The motor 52 is fixed in any suitable way to the rear of the support plate 2 of the device, with the shaft 50 extending through an aperture in the support plate 2 to carry the guide 14 in front of the support plate. These mechanical details are not illustrated in the drawings because they do not themselves form part of the invention and can be effected using very well known techniques, as also can the electronic control circuitry used to cause the stepper motor 52 to selectively position the guide 14 with its common outlet 18 in register with any desired one of the eleven exit passageways 12.
FIGS. 1(a) to 1(f) show the guide 14 positioned with the common outlet 18 in register sequentially with the middle one of the eleven exit passageways 12 through to the extreme right-hand one of the exit passageways 12. By step-wise rotation of the motor 52 in the opposite direction, the common outlet 18 can, of course, be positioned in register with the exit passageways 12 lying to the left of the middle one. The trailing flaps 42, 44, 46 and 48 are intended to be pivoted freely enough to hang under the force of gravity but if they do stick slightly, they can be brushed aside by an incoming coin. The effect of the flaps, as can be seen by inspecting the various views in FIG. 1, is to provide continuity from entry 6 to exit 12 of whichever channel within the guide 14 the particular coin is passing through. For example, in FIG. 1(a), the flaps 44 and 46 (see FIG. 2 for these reference numerals) are providing continuous side walls for the central channel 24; in FIG. 1(b) the flap 44 is providing a continuous side wall down which the coin can slide, again in central guidance channel 24; in FIG. 1(c), flap 46 is providing a continuous side wall for guidance channel 26, and similarly in FIG. 1(d); in FIG. 1(e), the trailing flaps 48 and 46 are in succession providing a continuous wall for the coin to slide on in guidance channel 28, as they are also in FIG. 1(f). It will be appreciated that the operation of the trailing flaps is in symmetrical manner when the guide 14 is rotated clockwise instead of anti-clockwise. It can also be seen from FIG. 1 that the trailing flaps do not obstruct channels. For example, the flap 46 is simply being pushed aside by the coin in the central channel in FIG. 1(b), as is the flap 48 by the coin in guidance channel 26 in FIG. 1(c) and 1(d).
FIGS. 1(a) to 1(f) show how the guidance channels, including the trailing flaps, are configured so that each of them will provide a relatively smooth non-angular path of travel for a coin from the entry 6 to the selected exit passageway 12, when the particular channel is the one being used to route the coin.
All the components along the coin path through the device are dimensioned to keep coins travelling edgeways without tumbling. The coins will tend to emerge from the common outlet 18 in different directions for different rotary positions of the guide, as can be seen from FIG. 1. To further smooth the path of the coin the exit passageways 12 are profiled, by profiling the vanes 10 which define them. This profiling is most pronounced in the case of the outer extreme vanes 10, as can easily be seen from FIGS. 1 and 2, and becomes less pronounced for the vanes 10 progressively towards the centre. Referring to FIG. 1(f), it can been seen that the pronounced outward bulge 54 near the upper end of the extreme right-hand vane 10 allows plenty of room for the leading edge of a coin to enter well into the exit passageway and then to be relatively gently turned clockwise by contact with the lower and straighter part 56 of the vane. It can also be seen that the concavity 58 of the wall 40 in its lower region adjacent the common outlet 18 permits the trailing edge of the coin to swing clockwise as the coin turns.
This profiling of the exit passageways ensures minimal hindrance of the coins as they leave the guide 14 and enter into the respective passageway 12 and hence reduces the time which must be allowed to elapse before the guide is re-positioned for sorting of the next coin. The non-angular shapes of the paths through the guide 14 itself have the same effect. Consequently, both features contribute towards enhancing the throughput of the sorting or guiding device in terms of coins per unit time.
The profiling of the vanes 10 is extended downwards so that at the bottom of the device, where the coins are seen emerging, they are all travelling in substantially the same direction, namely vertically edgewise, and although their paths are laterally separate, they are nevertheless close together, which makes for compactness.
In the embodiment that has been described, and as can be seen from FIG. 1, the central inlet 16 remains in register with the entry 6 for all three of the most central positions of the common outlet 18, while each of the non-central inlets is in register with the entry 6 for two different adjacent positions of the common outlet 18. Thus, an acceptably smooth path to each of the eleven exit passageways can be provided without requiring a separate guidance channel through the guide 14 for each of its different positions, though it would be feasible to do this, but at the expense of greater structural complexity.
Although in the embodiment described the coin entry 6 and the exit passageways 12 are incorporated as part as the same physical unit as the rotary guide 14, it will be appreciated that the entry and the exits could be, or could be part of, different units from the guide 14 though of course they would cooperate with it in the operation of the sorting or guiding device as a whole. | A device for guiding a coin arriving in an entry (6) of the device to a selected one of a plurality of exits (12) of the device, comprising a movable guide (14) having a plurality of inlets (16) each leading to a common outlet (18), the guide being movable to position the outlet in register with any selected one of the exits, and the inlets being so arranged that one of them is in a position to admit a coin arriving through the entry irrespective of the position of the guide, whereby the coin is guided from the one inlet via the common outlet to the selected exit. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of priority from Provisional Application No. 60/838,546 filed Aug. 18, 2006. This application hereby incorporates by reference Provisional Application No. 60/838,546 in its entirety.
FIELD OF THE INVENTION
[0002] Herein disclosed is a fabric made from a high tenacity air textured multifilament yarn in combination with a high tenacity multifilament yarn. A portion of multifilament yarns which comprise the fabric are substantially without bulk or texture while the air textured portion of multifilament yarns comprising the fabric have bulk. Such “hybrid” fabrics from this combination of yarns retain substantially similar abrasion resistance and tactility of a fabric made entirely of high tenacity air textured multifilament yarns. Nylon woven “hybrid” fabrics disclosed herein provide excellent properties especially for uses in rucksacks, soft sided luggage, duffle bags, apparel and the like.
BACKGROUND OF THE INVENTION
[0003] Woven fabrics produced from bulky air textured yarns are certified as CORDURAO® branded fabrics (CORDURA® is a registered trademark for durable fabrics of INVISTA S. á r. I., Three Little Falls Centre, 2801 Centreville Road, Wilmington, Del., 19808, USA). These fabrics comprise high tenacity air jet textured nylon multifilament yarns are used in luggage, backpacks, duffle bags, work-wear apparel, shoes and applications where a high strength and durable fabric is desirable In addition, conventional dye stuffs for nylon can be used to dye CORDURAO® fabrics made from high tenacity nylon multifilament yarns. Alternatively, CORDURAO® fabrics are provided from yarns which are “solution dyed.” Solution dyed means having a pigment coloration compounded with the polymer where after dyeing the yarn or fabric is not needed or desirable. CORDURA® fabrics are often coated on at least one surface with coating materials and films employed in the art, e.g. perfluoropolymers, polyurethanes, latex, acrylics and silicones. In general such coatings impart a further resistance of the fabric to liquid penetration, staining and soiling.
SUMMARY OF THE INVENTION
[0004] An illustrative embodiment provided by the teachings herein is a fabric of multifilament yarns comprising at least a first yarn in a first fabric direction and at least a second yarn in a fabric direction perpendicular to the first direction and wherein the yarn in the first direction is chosen to have substantially minimal bulk and the second yarn is chosen to have a bulk level in a range of about 6 cm 3 /gram to about 12 cm 3 /gram.
[0005] Another illustrative embodiment provided by the teachings herein is a woven fabric of nylon multifilament yarns comprising a warp yarn and a weft yarn comprising a warp yarn chosen to have substantially minimal bulk and the weft yarn having a bulk level in a range of about 6 cm 3 /gram to about 12 cm 3 /gram.
[0006] Another illustrative embodiment provided by the teachings herein is a woven fabric of nylon multifilament yarns comprising a warp yarn and a weft yarn comprising a weft yarn chosen to have substantially minimal bulk and the warp yarn having a bulk level in a range of about 6 cm 3 /gram to about 12 cm 3 /gram.
[0007] Another illustrative embodiment provided by the teachings herein is a fabric of multifilament yarns comprising at least a first multifilament yarn in a first fabric direction and at least a second multifilament yarn in a fabric direction perpendicular to the first direction and wherein the yarn in the first direction is chosen to have a tenacity in a range of about 1.7 to 6.3 grams per denier and the second yarn is chosen a tenacity in a range of about 2 to 7.5 grams per denier.
[0008] Another illustrative embodiment provided by the teachings herein is a fabric of comprising first multifilament yarns chosen to have a tenacity of about 20% to about 25% greater than the tenacity of the second multifilament yarns.
BRIEF DESCRIPTION OF THE FIGURE
[0009] FIG. 1 is a representation of two dyed fabrics identified as A and B.
DETAILED DESCRIPTION OF THE INVENTION
[0010] According to an illustrative embodiment, a fabric comprising two different yarns is provided. The two different yarns comprising the fabric embodiment can be at least one of textured (bulky) type and at least one of untextured (having minimal bulk) type. More generally, the two different yarns are processed into a “hybrid” fabric where a textured (bulky) type yarn predominates in a first direction of the fabric and the untextured (having minimal bulk) type predominates in a second direction of the fabric perpendicular to the first direction of the fabric.
[0011] According to an illustrative embodiment, a fabric comprising two different yarns woven in warp and weft directions is provided. The two different yarns comprising the woven fabric embodiment can be at least one of textured (bulky) type and at least one of a substantially untextured (having minimal bulk) type. More generally, the two different yarns are processed into a fabric where a textured (bulky) type yarn predominates in a warp direction of the fabric and the substantially untextured (having minimal bulk) type predominates in a weft of the fabric.
[0012] According to an illustrative embodiment, the two different yarns are processed into a fabric where a textured (bulky) type yarn predominates in a weft direction of the fabric and the substantially untextured (having minimal bulk) type predominates in a warp of the fabric.
[0013] According to a more general illustrative embodiment, fabrics of such two different yarns (textured and substantially untextured) have a visual aesthetic of at least equal to but generally superior to known fabrics comprised substantially of bulked yarns (air jet textured multifilament yarns).
[0014] According to a more general illustrative embodiment, the fabrics provide for a substantial absence of “warp streaks”, as revealed by diagnostic dyeing and visual rating. Such fabrics are advantageously used in certain apparel applications, e.g. work wear and military uniforms. One such advantage is at least the economical production of fabrics having only a portion of the yarns air jet textured. Back packs (rucksacks), active wear apparel, shoes, boots and duffle bags are especially well-suited to construction from the fabrics of the general illustrative embodiment.
[0015] According to a more general illustrative embodiment, the fabric comprises a portion of substantially untextured yarns having a yarn tenacity equal to 20% and greater than the tenacity of the air jet textured yarns comprising the remainder of the fabric. Such fabrics have the aesthetics (i.e. look and feel) of a 100% warp×weft air jet textured fabric, but with superior tensile strength properties in the direction of the substantially untextured yarn component.
[0016] It is believed by those skilled in the art that some processes of air jet texturing to impart bulk into yarn can reduce yarn tenacity by as much as 20-25%. By not texturing a portion of component yarns in the fabric, the fabric strength can be improved. This improvement in fabric strength can be nearly equivalent to the amount of improvement in yarn tenacity obtained by not air jet texturing.
[0017] According to a more general illustrative embodiment, the fabric abrasion resistance (a factor of yarn tenacity and yarn bulk) is reduced somewhat, but substantially unchanged from fabrics comprising air jet textured bulky yarns in both warp and weft directions. In general, abrasion resistance may be reduced by lowering the bulk, but the higher tenacity of unbulked warp yarns provides this substantially unchanged abrasion resistance.
[0018] An illustrative embodiment provided by the teachings herein is a fabric of multifilament yarns comprising at least a first yarn in a first fabric direction and at least a second yarn in a fabric direction perpendicular to the first direction and wherein the yarn in the first direction is chosen to have substantially minimal bulk and the second yarn is chosen to have a bulk level in a range of about 6 cm 3 /gram to about 12 cm 3 /gram.
[0019] Another illustrative embodiment provided by the teachings herein is a woven fabric of nylon multifilament yarns comprising a warp yarn and a weft yarn comprising a warp yarn chosen to have substantially minimal bulk and the weft yarn having a bulk level in a range of about 6 cm 3 /gram to about 12 cm 3 /gram.
[0020] Another illustrative embodiment provided by the teachings herein is a fabric of multifilament yarns comprising at least a first multifilament yarn in a first fabric direction and at least a second multifilament yarn in a fabric direction perpendicular to the first direction and wherein the yarn in the first direction is chosen to have a tenacity in a range of about 1.7 to 6.3 grams per denier and the second yarn is chosen a tenacity in a range of about 2 to 7.5 grams per denier.
[0021] Another illustrative embodiment provided by the teachings herein is a fabric of comprising first multifilament yarn chosen to have a tenacity of about 20% greater than the tenacity of the second multifilament yarn.
[0022] Other illustrative embodiments of the hybrid fabric may be chosen from woven having a plain weave, a 2 by 2 twill weave and ripstop weave. The hybrid fabric may be colored using known methods chosen from dyeing and printing. The hybrid fabric may comprise yarns chosen from solution dyed yarns. The hybrid fabric may comprise yarns chosen from synthetic polyamides, synthetic polyesters, acrylics, cotton, and wool. The hybrid fabric may comprise yarns chosen from yarns of about 300 denier to about 1500 denier. The hybrid fabric may comprise yarns chosen from multifilament yarns of about 2 denier per filament to about 10 denier per filament. The hybrid fabric may comprise fabrics having a basis weight chosen from about 240 grams per square meter to about 410 grams per square meter.
[0023] Another illustrative embodiment provided by the teachings herein is an article comprising a hybrid fabric wherein the article is chosen from apparel, soft sided luggage, rucksacks, duffle bags and tents. The article may further comprise a hybrid fabric coated on at least one surface with a coating material or film chosen from polyurethanes, latex, acrylics and silicones.
[0024] The air jet textured yarns herein disclosed are available from INVISTA™ S. á r. I., Three Little Falls Center, 2801 Centerville Road, Wilmington, Del. USA 19808. In general, such textured multifilament yarns are distinguished by their bulk level versus an untextured yarn. Bulk in the yarn is obtained by leading the yarn through an air jet at a rate faster than it is drawn off on the far side of the jet. In the jet, the yarn multifilament structure is opened, loops are formed, and the structure is closed again. Some loops are locked inside and others are locked on the surface of the yarn. The net effect is that these textured yarns are characterized by a volume per unit mass (e.g. measured in cubic centimeters per gram) higher than the volume per unit mass of a substantially untextured yarn. An untextured yarn is one having a closed multifilament structure having substantially no loop structure which results in minimal bulk. Textured yarn bulk can be measured by a method based on cutting a length of sample, weighing the sample and determining the volume of the substantially uncompacted sample.
Test Methods
[0025] Fabric “Grab Strength” according to ASTM D5034. A test specimen of 4 inch (10 cm) width and at least 6 inch (15 cm) long is clamped with jaws 1 inch (2.54 cm) wide and centered across the test specimen width at 3 inches (7.6 cm) apart. The breaking strength obtained includes any reinforcing effects of the fabric not held by the clamping jaws. The strength is reported in pounds of force (4.447 Newtons per pound).
[0026] Fabric “Tear Strength” according to ASTM D2261.
[0027] Abrasion (Taber) according to ASTM D3884.
[0028] Abrasion (Wyzenbeek) according to ASTM D4157.
[0029] KES Test Method for Fabric Evaluation: The method is disclosed in the publication entitled “Objective Specification of Fabric Quality, Mechanical Properties and Performance” edited by S. Kawabata, R. Postle, and M. Niwa—published by The Textile Machinery Society of Japan, 1982; Osaka Science and Technology Center Bid., 8-4, Utsbo-1-chome, Nishi-ku, Osaka 550 Japan.
[0030] The KES Test Method determines fabric surface characteristics expressed in terms of: MIU—Coefficient of friction; MMD—Mean deviation of MIU; SMD—Geometrical roughness (micrometers).
[0031] Yarn tensile testing (with percent elongation at break) may be performed according to ASTM D2256 with the use of a INSTRON universal materials tensile testing instrument using CRE machine, Option 1A; D1907 Option 1 denier for calculations. The nominal yarn tenacity for 500 denier yarn used herein is 22.2 Newtons (4.52 grams per denier) and for 1000 denier yarn used herein is 46.3-48 Newtons (4.72 to 4.89 grams per denier).
[0032] Yarn denier (grams per 9000 meters) is measured in the known manner (ASTM 1059) using a cut and weigh apparatus for measuring linear densities. The decitex, another linear density expression is in grams per 10 000 meters.
EXAMPLES
[0033] For the purpose of comparison to an example of an illustrative embodiment, a fabric was woven using a conventional weaving loom in a plain weave. The warp yarns were multifilament nylon high tenacity air jet bulked of 1000 denier and 140 filaments per yarn. The fill (weft) yarns were the same bulked of 1000 denier and 140 filaments per yarn. Each yarn had a nominal bulk level of 10.5 cm 3 /gram. The thread count was 34 warp yarns per inch×28 weft yarns per inch (13.4 per cm×11 per cm). This fabric basis weight was 8.23 ounces per square yard (0.279 kilogram/square meter). This fabric had grab strength in the warp direction of 620.68 pounds (281 kilograms) and in the weft direction a grab strength of 516.66 pounds (234 kilograms). This fabric is suitable for certification as a CORDURA® fabric.
[0000]
TABLE 1
CFS-83-10(CORDURA ® fabric of air
jet textured yarns); Style GF 1091 - 28
WT - 8.23 oz/yd 2 = 279 grams per square meter
Weave - Plain; No size
Warp yarn: 1000 denier/140 filaments - 440 bright air jet textured
nylon 66*
Weft: 1000 denier/140 filaments - 440 bright air jet textured nylon 66*
*available from INVISTA ™ S.àr.l., Three Little Falls Center, 2801 Centerville Road, Wilmington, Delaware USA 19808.
[0034] As an example of an illustrative embodiment, a fabric was woven using a conventional weaving loom in a plain weave according to known methods. The warp yarns of the woven fabric were multifilament nylon high tenacity un-bulked yarn of 950 denier and 140 filaments per yarn. The weft (fill) yarns of the woven fabric were an air-jet bulked yarn of 1000 denier and 140 filaments per yarn, their nominal bulk level was 10.5 cm 3 /gram. The yarns were woven with sizing applied in the known manner. The sizing was an aqueous polyacrylic acid known for use with nylon yarns, e.g. ABCO Plasticryl (A-34. The thread count (Warp×Fill) in ends-per-inch was 33.5 warp yarns per inch×28 weft yarns per inch (13.2 per cm×11 per cm). This “hybrid” finished fabric was 8.05 ounces per square yard (0.273 kilogram/square meter). This “hybrid” fabric had grab strength in the warp direction of 730.43 pounds (331 kilograms) and in the fill direction a grab strength of 519.07 pounds (235 kilograms).
[0000]
TABLE 2
CFS 83-11 (Hybrid - Flat warp, air
jet textured weft); Style GF 950-28
Wt - 8.05 oz/yd 2 = 273 grams per square meter
Weave - Plain;
Size - ABCO Plasticryl A-34
Warp yarn: 950 denier/140 filaments R20 Bright HT nylon 66**
Weft yarn: 1000 denier/140 filaments 440 bright air jet textured nylon 66*
*available from INVISTA ™ S.àr.l., Three Little Falls Center, 2801 Centerville Road, Wilmington, Delaware USA 19808.
**available from INVISTA ™ S.àr.l., Three Little Falls Center, 2801 Centerville Road, Wilmington, Delaware USA 19808.
[0000]
TABLE 3
KES Testing for Fabric
Warp direction
Weft direction
Tactile Properties
measurements
measurements
CFS-83-11
MIU = 0.169
MIU = 0.222
CORDURA ® Fabric
MMD = 0.0305
MMD = 0.0407
warp and weft
SMD = 19.26
SMD = 13.40
CFS-83-10 Hybrid Fabric
MIU = 0.161
MIU = 0.223
untextured warp and
MMD = 0.0408
MMD = 0.0277
air jet weft
SMD - 20.00
SMD = 8.24
[0035] Using the standard KES Testing Methods for Fabric Tactile Properties two fabric samples were tested; the results are posted in Table 3. The “hybrid fabric” is an illustrative embodiment having an air jet textured weft yarn and an untextured warp yarn. The CORDURAO® fabric data is provided for comparison. These data show little difference in the values for MIU (coefficient of friction) as this is largely a material property. MMD the mean deviation of the coefficient of friction is lower for CFS-83-11 than for CFS-83-10 in the weft direction. The same is true for the weft direction SMD (surface roughness) measurements. It is believed these data account for the perception of improved smoothness for the hybrid fabric (CFS-83-11) versus the CORDURA® fabric (CFS-83-10) found by a panel of fabric rating experts.
Diagnostic Dyeing Procedure
[0036] The fabrics (both CFS-83-11 and CFS-83-10) were pre-scoured at 72° C. for 30 minutes in a bath comprising 1 gram per liter Merpol HCS (non-ionic wetting agent) and 1 gram per liter trisodium phosphate. These fabric dyeing were performed in a bath at 27° C. with 5 gram per liter monosodium phosphate at pH 5. The fabric and dye bath was maintained for 5 minutes followed by addition of a pre-dissolved dyestuff 1% Nylosan Violet F-BL and maintained for 5 minutes. The dye bath was raised in temperature to 100° C. and maintained for 30 minutes. Afterwards, the bath and fabric were cooled to 76° C. The fabric was removed, rinsed of dyestuffs and auxiliaries and dried. The woven and dyed fabric was rated for uniformity by a panel of experts in diagnostic dyeing. The panel concluded that the “hybrid” fabric having with the unbulked warp yarns and air jet textured weft yarns dyed to a more uniform coloration in comparison to a fabric similarly prepared using CORDURA® fabric (CFS-83-10 fabric). FIG. 1 is a representation of the diagnostic dyeing results for the two fabrics A and B. In FIG. 1 this hybrid fabric (CFS-83-11) embodiment is designated as B and the CORDURAO® fabric (CFS-83-10) is designated as A.
[0037] The foregoing disclosure constitutes a description of specific embodiments illustrating how the invention may be used and applied. Such embodiments are only exemplary. The invention in its broadest aspects is further defined in the claims which follow. These claims and terms used therein are to be taken as variants of the invention described. These claims are not restricted to such variants but are to be read as covering the full scope of the invention implicit within the disclosure herein. | This disclosure relates to a “hybrid” fabric made from a textured multifilament yarn in combination with an untextured multifilament yarn. The portion of multifilament yarns comprising this hybrid fabric are substantially without bulk or texture while the textured portion of multifilament yarns comprising the fabric have bulk. Such hybrid fabrics from this combination of yarns retain substantially similar abrasion resistance and tactility of a fabric made entirely of high tenacity air textured multifilament yarns. Nylon woven hybrid fabrics disclosed herein provide excellent properties especially for uses in apparel, rucksacks, softsided luggage, duffle bags, tenting and the like. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application No. 61/326,294 filed on Apr. 21, 2010, the entire contents of which are incorporated herein by reference.
BACKGROUND
The present disclosure relates to a coordinate measuring device. One set of coordinate measurement devices belongs to a class of instruments that measure the three-dimensional (3D) coordinates of a point by sending a laser beam to the point, where it is intercepted by a retroreflector target. The instrument finds the coordinates of the point by measuring the distance and the two angles to the target. The distance is measured with a distance-measuring device such as an absolute distance meter (ADM) or an interferometer. The angles are measured with an angle-measuring device such as an angular encoder. A gimbaled beam-steering mechanism within the instrument directs the laser beam to the point of interest. An example of such a device is a laser tracker. Exemplary laser tracker systems are described by U.S. Pat. No. 4,790,651 to Brown et al., incorporated by reference herein, and U.S. Pat. No. 4,714,339 to Lau et al.
A coordinate-measuring device closely related to the laser tracker is the total station. The total station, which is most often used in surveying applications, may be used to measure the coordinates of diffusely scattering or retroreflective targets. Hereinafter, the term laser tracker is used in a broad sense to include total stations.
Ordinarily the laser tracker sends a laser beam to a retroreflector target. A common type of retroreflector target is the spherically mounted retroreflector (SMR), which comprises a cube-corner retroreflector embedded within a metal sphere. The cube-corner retroreflector comprises three mutually perpendicular mirrors. The apex of the cube corner, which is the common point of intersection of the three mirrors, is located at the center of the sphere. It is common practice to place the spherical surface of the SMR in contact with an object under test and then move the SMR over the surface being measured. Because of this placement of the cube corner within the sphere, the perpendicular distance from the apex of the cube corner to the surface of the object under test remains constant despite rotation of the SMR. Consequently, the 3D coordinates of a surface can be found by having a tracker follow the 3D coordinates of an SMR moved over the surface. It is possible to place a glass window on the top of the SMR to prevent dust or dirt from contaminating the glass surfaces. An example of such a glass surface is shown in U.S. Pat. No. 7,388,654 to Raab et al., incorporated by reference herein.
A gimbal mechanism within the laser tracker may be used to direct a laser beam from the tracker to the SMR. Part of the light retroreflected by the SMR enters the laser tracker and passes onto a position detector. The position of the light that hits the position detector is used by a tracker control system to adjust the rotation angles of the mechanical azimuth and zenith axes of the laser tracker to keep the laser beam centered on the SMR. In this way, the tracker is able to follow (track) the SMR.
Angular encoders attached to the mechanical azimuth and zenith axes of the tracker may measure the azimuth and zenith angles of the laser beam (with respect to the tracker frame of reference). The one distance measurement and two angle measurements performed by the laser tracker are sufficient to completely specify the three-dimensional location of the SMR.
As mentioned previously, two types of distance meters may be found in laser trackers: interferometers and absolute distance meters (ADMs). In the laser tracker, an interferometer (if present) may determine the distance from a starting point to a finishing point by counting the number of increments of known length (usually the half-wavelength of the laser light) that pass as a retroreflector target is moved between the two points. If the beam is broken during the measurement, the number of counts cannot be accurately known, causing the distance information to be lost. By comparison, the ADM in a laser tracker determines the absolute distance to a retroreflector target without regard to beam breaks, which also allows switching between targets. Because of this, the ADM is said to be capable of “point-and-shoot” measurement. Initially, absolute distance meters were only able to measure stationary targets and for this reason were always used together with an interferometer. However, some modern absolute distance meters can make rapid measurements, thereby eliminating the need for an interferometer. Such an ADM is described in U.S. Pat. No. 7,352,446 to Bridges et al., incorporated by reference herein.
In its tracking mode, the laser tracker will automatically follow movements of the SMR when the SMR is in the capture range of the tracker. If the laser beam is broken, tracking will stop. The beam may be broken by any of several means: (1) an obstruction between the instrument and SMR; (2) rapid movements of the SMR that are too fast for the instrument to follow; or (3) the direction of the SMR being turned beyond the acceptance angle of the SMR. By default, following the beam break, the beam remains fixed at the point of the beam break or at the last commanded position. It may be necessary for an operator to visually search for the tracking beam and place the SMR in the beam in order to lock the instrument onto the SMR and continue tracking.
Some laser trackers include one or more cameras. A camera axis may be coaxial with the measurement beam or offset from the measurement beam by a fixed distance or angle. A camera may be used to provide a wide field of view to locate retroreflectors. A modulated light source placed near the camera optical axis may illuminate retroreflectors, thereby making them easier to identify. In this case, the retroreflectors flash in phase with the illumination, whereas background objects do not. One application for such a camera is to detect multiple retroreflectors in the field of view and measure each in an automated sequence. Exemplary systems are described in U.S. Pat. No. 6,166,809 to Pettersen et al., and U.S. Pat. No. 7,800,758 to Bridges et al., incorporated by reference herein.
Some laser trackers have the ability to measure with six degrees of freedom (DOF), which may include three coordinates, such as x, y, and z, and three rotations, such as pitch, roll, and yaw. Several systems based on laser trackers are available or have been proposed for measuring six degrees of freedom. Exemplary systems are described in U.S. Published Patent Application No. 2010/0128259 to Bridges, incorporated by reference herein; U.S. Pat. No. 7,800,758 to Bridges et al., U.S. Pat. No. 5,973,788 to Pettersen et al.; and U.S. Pat. No. 7,230,689 to Lau.
User Control of Laser Tracker Functionality
Two common modes of operation of the laser tracker are tracking mode and profiling mode. In tracking mode, the laser beam from the tracker follows the retroreflector as the operator moves it around. In profiling mode, the laser beam from the tracker goes in the direction given by the operator, either through computer commands or manual action.
Besides these modes of operation that control the basic tracking and pointing behavior of the tracker, there are also special option modes that enable the tracker to respond in a manner selected by the operator ahead of time. The desired option mode is typically selected in software that controls the laser tracker. Such software may reside in an external computer attached to the tracker (possibly through a network cable) or within the tracker itself. In the latter case, the software may be accessed through console functionality built into the tracker.
An example of an option mode is the Auto Reset mode in which the laser beam is driven to a preset reference point whenever the laser beam is broken. One popular reference point for the Auto Reset option mode is the tracker Home Position, which is the position of a magnetic nest mounted on the tracker body. The alternative to Auto Reset is the No Reset option mode. In this case, the laser beam continues pointing in the original direction whenever the laser beam is broken. A description of the tracker home position is given in U.S. Pat. No. 7,327,446 to Cramer et al., incorporated by reference herein.
Another example of a special option mode is PowerLock, a feature offered by Leica Geosystems on their Leica Absolute Tracker™. In the PowerLock option mode, the location of the retroreflector is found by a tracker camera whenever the tracker laser beam is broken. The camera immediately sends the angular coordinates of the retroreflector to the tracker control system, thereby causing the tracker to point the laser beam back at the retroreflector. Methods involving automatic acquisition of a retroreflector are given in international application WO 2007/079601 to Dold et al. and U.S. Pat. No. 7,055,253 to Kaneko.
Some option modes are slightly more complex in their operation. An example is the Stability Criterion mode, which may be invoked whenever an SMR is stationary for a given period of time. The operator may track an SMR to a magnetic nest and set it down. If a stability criterion is active, the software will begin to look at the stability of the three-dimensional coordinate readings of the tracker. For instance, the user may decide to judge the SMR to be stable if the peak-to-peak deviation in the distance reading of the SMR is less than two micrometers over a one second interval. After the stability criterion is satisfied, the tracker measures the 3D coordinates and the software records the data.
More complex modes of operation are possible through computer programs. For example, software is available to measure part surfaces and fit these to geometrical shapes. Software will instruct the operator to move the SMR over the surface and then, when finished collecting data points, to raise the SMR off the surface of the object to end the measurement. Moving the SMR off the surface not only indicates that the measurement is completed; it also indicates the position of the SMR in relation to the object surface. This position information is needed by the application software to properly account for the offset caused by the SMR radius.
A second example of complex computer control is a tracker survey. In the survey, the tracker is driven sequentially to each of several target locations according to a prearranged schedule. The operator may teach these positions prior to the survey by carrying the SMR to each of the desired positions.
A third example of complex software control is tracker directed measurement. The software directs the operator to move the SMR to a desired location. It does this using a graphic display to show the direction and distance to the desired location. When the operator is at the desired position, the color on the computer monitor might, for example, turn from red to green.
The element common to all tracker actions described above is that the operator is limited in his ability to control the behavior of the tracker. On the one hand, option modes selected in the software may enable the operator to preset certain behaviors of the tracker. However, once the option modes have been selected by the user, the behavior of the tracker is established and cannot be changed unless the operator returns to the computer console. On the other hand, the computer program may direct the operator to carry out complicated operations that the software analyzes in a sophisticated way. In either case, the operator is limited in his ability to control the tracker and the data collected by the tracker.
Need for Remote Tracker Commands
A laser tracker operator performs two fundamental functions. He positions an SMR during a measurement, and he sends commands through the control computer to the tracker. However, it is not easy for one operator to perform both of these measurement functions because the computer is usually far away from the measurement location. Various methods have been tried to get around this limitation, but none is completely satisfactory.
One method sometimes used is for a single operator to set the retroreflector in place and walk back to the instrument control keyboard to execute a measurement instruction. However, this is an inefficient use of operator and instrument time. In cases where the operator must hold the retroreflector for the measurement, single operator control is only possible when the operator is very close to the keyboard.
A second method is to add a second operator. One operator stands by the computer and a second operator moves the SMR. This is obviously an expensive method and verbal communication over large distances can be a problem.
A third method is to equip a laser tracker with a remote control. However, remote controls have several limitations. Many facilities do not allow the use of remote controls for safety or security reasons. Even if remote controls are allowed, interference among wireless channels may be a problem. Some remote control signals do not reach the full range of the laser tracker. In some situations, such as working from a ladder, the second hand may not be free to operate the remote control. Before a remote control can be used, it is usually necessary to set up the computer and remote control to work together, and then only a small subset of tracker commands can ordinarily be accessed at any given time. An example of a system based on this idea is given in U.S. Pat. No. 7,233,316 to Smith et al.
A fourth method is to interface a cell phone to a laser tracker. Commands are entered remotely by calling the instrument from the cell phone and entering numbers from the cell phone keypad or by means of voice recognition. This method also has many shortcomings. Some facilities do not allow cell phones to be used, and cell phones may not be available in rural areas. Service requires a monthly service provider fee. A cell phone interface requires additional hardware interfacing to the computer or laser tracker. Cell phone technology changes fast and may require upgrades. As in the case of remote controls, the computer and remote control must be set up to work together, and only a small subset of tracker commands can ordinarily be accessed at a given time.
A fifth method is to equip a laser tracker with internet or wireless network capabilities and use a wireless portable computer or personal digital assistant (PDA) to communicate commands to the laser tracker. However, this method has limitations similar to a cell phone. This method is often used with total stations. Examples of systems that use this method include U.S. Published Patent Application No. 2009/017618 to Kumagai et al., U.S. Pat. No. 6,034,722 to Viney et al., U.S. Pat. No. 7,423,742 to Gatsios et al., U.S. Pat. No. 7,307,710 to Gatsios et al., U.S. Pat. No. 7,552,539 to Piekutowski, and U.S. Pat. No. 6,133,998 to Monz et al. This method has also been used to control appliances by a method described in U.S. Pat. No. 7,541,965 to Ouchi et al.
A sixth method is to use a pointer to indicate a particular location in which a measurement is to be made. An example of this method is given in U.S. Pat. No. 7,022,971 to Ura et al. It might be possible to adapt this method to give commands to a laser tracker, but it is not usually very easy to find a suitable surface upon which to project the pointer beam pattern.
A seventh method is to devise a complex target structure containing at least a retroreflector, transmitter, and receiver. Such systems may be used with total stations to transmit precise target information to the operator and also to transmit global positioning system (GPS) information to the total station. An example of such a system is given in U.S. Published Patent Application No. 2008/0229592 to Hinderling et al. In this case, no method is provided to enable the operator to send commands to the measurement device (total station).
An eighth method is to devise a complex target structure containing at least a retroreflector, transmitter and receiver, where the transmitter has the ability to send modulated light signals to a total station. A keypad can be used to send commands to the total station by means of the modulated light. These commands are decoded by the total station. Examples of such systems are given in U.S. Pat. No. 6,023,326 to Katayama et al., U.S. Pat. No. 6,462,810 to Muraoka et al., U.S. Pat. No. 6,295,174 to Ishinabe et al., and U.S. Pat. No. 6,587,244 to Ishinabe et al. This method is particularly appropriate for surveying applications in which the complex target and keypad are mounted on a large staff. Such a method is not suitable for use with a laser tracker, where it is advantageous to use a small target not tethered to a large control pad. Also it is desirable to have the ability to send commands even when the tracker is not locked onto a retroreflector target.
A ninth method is to include both a wireless transmitter and a modulated light source on the target to send information to a total station. The wireless transmitter primarily sends information on the angular pose of the target so that the total station can turn in the proper direction to send its laser beam to the target retroreflector. The modulated light source is placed near the retroreflector so that it will be picked up by the detector in the total station. In this way, the operator can be assured that the total station is pointed in the right direction, thereby avoiding false reflections that do not come from the target retroreflector. An exemplary system based on this approach is given in U.S. Pat. No. 5,313,409 to Wiklund et al. This method does not offer the ability to send general purpose commands to a laser tracker.
A tenth method is to include a combination of wireless transmitter, compass assembly in both target and total station, and guide light transmitter. The compass assembly in the target and total station are used to enable alignment of the azimuth angle of the total station to the target. The guide light transmitter is a horizontal fan of light that the target can pan in the vertical direction until a signal is received on the detector within the total station. Once the guide light has been centered on the detector, the total station adjusts its orientation slightly to maximize the retroreflected signal. The wireless transmitter communicates information entered by the operator on a keypad located at the target. An exemplary system based on this method is given in U.S. Pat. No. 7,304,729 to Wasutomi et al. This method does not offer the ability to send general purpose commands to a laser tracker.
An eleventh method is to modify the retroreflector to enable temporal modulation to be imposed on the retroreflected light, thereby transmitting data. The inventive retroreflector comprises a cube corner having a truncated apex, an optical switch attached to the front face of the cube corner, and electronics to transmit or receive data. An exemplary system of this type is given in U.S. Pat. No. 5,121,242 to Kennedy. This type of retroreflector is complex and expensive. It degrades the quality of the retroreflected light because of the switch (which might be a ferro-electric light crystal material) and because of the truncated apex. Also, the light returned to a laser tracker is already modulated for use in measuring the ADM beam, and switching the light on and off would be a problem, not only for the ADM, but also for the tracker interferometer and position detector.
A twelfth method is to use a measuring device that contains a bidirectional transmitter for communicating with a target and an active retroreflector to assist in identifying the retroreflector. The bidirectional transmitter may be wireless or optical and is part of a complex target staff that includes the retroreflector, transmitter, and control unit. An exemplary system of this type is described in U.S. Pat. No. 5,828,057 to Hertzman et al. Such a method is not suitable for use with a laser tracker, where it is advantageous to use a small target not tethered to a large control pad. Also the method of identifying the retroreflector target of interest is complicated and expensive.
There is a need for a simple method for an operator to communicate commands to a laser tracker from a distance. It is desirable that the method be: (1) useable without a second operator; (2) useable over the entire range of the laser tracker; (3) useable without additional hardware interfacing; (4) functional in all locations; (5) free of service provider fees; (6) free of security restrictions; (7) easy to use without additional setup or programming; (8) capable of initiating a wide range of simple and complex tracker commands; (9) useable to call a tracker to a particular target among a plurality of targets; and (10) useable with a minimum of additional equipment for the operator to carry.
SUMMARY
A method for optically communicating, from a user to a laser tracker, a command to control operation of the laser tracker includes steps of providing a rule of correspondence between each of a plurality of commands and each of a plurality of spatial patterns, and selecting by the user a first command from among the plurality of commands. The method further includes the steps of moving by the user, between a first time and a second time, a retroreflector in a first spatial pattern from among the plurality of spatial patterns, wherein the first spatial pattern corresponds to the first command, and projecting a first light from the laser tracker to the retroreflector. The method also includes the steps of reflecting a second light from the retroreflector, the second light being a portion of the first light, and obtaining first sensed data by sensing a third light, the third light being a portion of the second light, wherein the first sensed data is obtained by the laser tracker between the first time and the second time. The method includes also the steps of determining the first command based at least in part on processing the first sensed data according to the rule of correspondence, and executing the first command with the laser tracker.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings, wherein like elements are numbered alike in the several FIGURES:
FIG. 1 shows a perspective view of an exemplary laser tracker;
FIG. 2 shows computing and power supply elements attached to exemplary laser tracker;
FIGS. 3A-3E illustrate ways in which a passive target can be used to convey gestural information through the tracking and measuring systems of the laser tracker;
FIGS. 4A-4C illustrate ways in which a passive target can be used to convey gestural information through the camera system of a laser tracker;
FIGS. 5A-5D illustrate ways in which an active target can be used to convey gestural information through the camera system of a laser tracker;
FIG. 6 is a flow chart showing the steps carried out by the operator and laser tracker in issuing and carrying out a gestural command;
FIG. 7 is a flow chart showing the optional and required parts of a gestural command;
FIGS. 8-10 show a selection of laser tracker commands and corresponding gestures that might be used by the operator to convey these commands to the laser tracker;
FIGS. 11A-11F show alternative types of gestures that might be used;
FIG. 12 shows an exemplary command tablet for transmitting commands to a laser tracker by means of gestures;
FIG. 13 shows an exemplary method for using gestures to set a tracker reference point;
FIG. 14 shows an exemplary method for using gestures to initialize the exemplary command tablet;
FIG. 15 shows an exemplary method for using gestures to measure a circle;
FIG. 16 shows an exemplary method for using gestures to acquire a retroreflector with a laser beam from a laser tracker;
FIG. 17 shows an exemplary electronics and processing system associated with a laser tracker;
FIG. 18 shows an exemplary geometry that enables finding of three dimensional coordinates of a target using a camera located off the optical axis of a laser tracker;
FIG. 19 shows an exemplary method for communicating a command to a laser tracker by gesturing with a retroreflector in a spatial pattern;
FIG. 20 shows an exemplary method for communicating a command to a laser tracker by indicating a position with a retroreflector;
FIG. 21 shows an exemplary method for communicating a command to a laser tracker by gesturing with a retroreflector in a temporal pattern;
FIG. 22 shows an exemplary method for communicating a command to a laser tracker by measuring a change in the pose of a six DOF target with a six DOF laser tracker;
FIG. 23 shows an exemplary method for communicating a command to point the laser beam from the laser tracker to a retroreflector and lock onto the retroreflector, the communication based on a gesture involving a spatial pattern created with the retroreflector;
FIG. 24 shows an exemplary method for communicating a command to point the laser beam from the laser tracker to a retroreflector and lock onto the retroreflector, the communication based on a gesture involving a temporal pattern in the optical power received by the laser tracker; and
FIG. 25 shows an exemplary method for communicating a command to point the laser beam from the laser tracker to a retroreflector and lock onto the retroreflector, the communication based on a gesture involving a change in the pose of a six DOF probe.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An exemplary laser tracker 10 is illustrated in FIG. 1 . An exemplary gimbaled beam-steering mechanism 12 of laser tracker 10 comprises zenith carriage 14 mounted on azimuth base 16 and rotated about azimuth axis 20 . Payload 15 is mounted on zenith carriage 14 and rotated about zenith axis 18 . Zenith mechanical rotation axis 18 and azimuth mechanical rotation axis 20 intersect orthogonally, internally to tracker 10 , at gimbal point 22 , which is typically the origin for distance measurements. Laser beam 46 virtually passes through gimbal point 22 and is pointed orthogonal to zenith axis 18 . In other words, laser beam 46 is in the plane normal to zenith axis 18 . Laser beam 46 is pointed in the desired direction by motors within the tracker (not shown) that rotate payload 15 about zenith axis 18 and azimuth axis 20 . Zenith and azimuth angular encoders, internal to the tracker (not shown), are attached to zenith mechanical axis 18 and azimuth mechanical axis 20 and indicate, to high accuracy, the angles of rotation. Laser beam 46 travels to external retroreflector 26 such as the spherically mounted retroreflector (SMR) described above. By measuring the radial distance between gimbal point 22 and retroreflector 26 and the rotation angles about the zenith and azimuth axes 18 , 20 , the position of retroreflector 26 is found within the spherical coordinate system of the tracker.
Laser beam 46 may comprise one or more laser wavelengths. For the sake of clarity and simplicity, a steering mechanism of the sort shown in FIG. 1 is assumed in the following discussion. However, other types of steering mechanisms are possible. For example, it would be possible to reflect a laser beam off a mirror rotated about the azimuth and zenith axes. An example of the use of a mirror in this way is given in U.S. Pat. No. 4,714,339 to Lau et al. The techniques described here are applicable, regardless of the type of steering mechanism.
In exemplary laser tracker 10 , cameras 52 and light sources 54 are located on payload 15 . Light sources 54 illuminate one or more retroreflector targets 26 . Light sources 54 may be LEDs electrically driven to repetitively emit pulsed light. Each camera 52 comprises a photosensitive array and a lens placed in front of the photosensitive array. The photosensitive array may be a CMOS or CCD array. The lens may have a relatively wide field of view, say thirty or forty degrees. The purpose of the lens is to form an image on the photosensitive array of objects within the field of view of the lens. Each light source 54 is placed near camera 52 so that light from light source 54 is reflected off each retroreflector target 26 onto camera 52 . In this way, retroreflector images are readily distinguished from the background on the photosensitive array as their image spots are brighter than background objects and are pulsed. There may be two cameras 52 and two light sources 54 placed about the line of laser beam 46 . By using two cameras in this way, the principle of triangulation can be used to find the three-dimensional coordinates of any SMR within the field of view of the camera. In addition, the three-dimensional coordinates of the SMR can be monitored as the SMR is moved from point to point. A use of two cameras for this purpose is described in U.S. Published Patent Application No. 2010/0128259 to Bridges.
Other arrangements of one or more cameras and light sources are possible. For example, a light source and camera can be coaxial or nearly coaxial with the laser beams emitted by the tracker. In this case, it may be necessary to use optical filtering or similar methods to avoid saturating the photosensitive array of the camera with the laser beam from the tracker.
Another possible arrangement is to use a single camera located on the payload or base of the tracker. A single camera, if located off the optical axis of the laser tracker, provides information about the two angles that define the direction to the retroreflector but not the distance to the retroreflector. In many cases, this information may be sufficient. If the 3D coordinates of the retroreflector are needed when using a single camera, one possibility is to rotate the tracker in the azimuth direction by 180 degrees and then to flip the zenith axis to point back at the retroreflector. In this way, the target can be viewed from two different directions and the 3D position of the retroreflector can be found using triangulation.
A more general approach to finding the distance to a retroreflector with a single camera is to rotate the laser tracker about either the azimuth axis or the zenith axis and observe the retroreflector with a camera located on the tracker for each of the two angles of rotation. The retroreflector may be illuminated, for example, by an LED located close to the camera. FIG. 18 shows how this procedure can be used to find the distance to the retroreflector. The test setup 900 includes a laser tracker 910 , a camera 920 in a first position, a camera 930 in a second position, and a retroreflector in a first position 940 and a second position 950 . The camera is moved from the first position to the second position by rotating the laser tracker 910 about the tracker gimbal point 912 about the azimuth axis, the zenith axis, or both the azimuth axis and the zenith axis. The camera 920 includes a lens system 922 and a photosensitive array 924 . The lens system 922 has a perspective center 926 through which rays of light from the retroreflectors 940 , 950 pass. The camera 930 is the same as the camera 920 except rotated into a different position. The distance from the surface of the laser tracker 910 to the retroreflector 940 is L 1 and the distance from the surface of the laser tracker to the retroreflector 950 is L 2 . The path from the gimbal point 912 to the perspective center 926 of the lens 922 is drawn along the line 914 . The path from the gimbal point 916 to the perspective center 936 of the lens 932 is drawn along the line 916 . The distances corresponding to the lines 914 and 916 have the same numerical value. As can be seen from FIG. 18 , the nearer position of the retroreflector 940 places an image spot 942 farther from the center of the photosensitive array than the image spot 952 corresponding to the photosensitive array 950 at the distance farther from the laser tracker. This same pattern holds true for the camera 930 located following the rotation. As a result, the distance between the image points of a nearby retroreflector 940 before and after rotation is larger than the distance between the image points of a far away retroreflector 950 before and after rotation. By rotating the laser tracker and noting the resulting change in position of the image spots on the photosensitive array, the distance to the retroreflector can be found. The method for finding this distance is easily found using trigonometry, as will be obvious to one of ordinary skill in the art.
Another possibility is to switch between measuring and imaging of the target. An example of such a method is described in U.S. Pat. No. 7,800,758 to Bridges et al. Other camera arrangements are possible and can be used with the methods described herein.
As shown in FIG. 2 , auxiliary unit 70 is usually a part of laser tracker 10 . The purpose of auxiliary unit 70 is to supply electrical power to the laser tracker body and in some cases to also supply computing and clocking capability to the system. It is possible to eliminate auxiliary unit 70 altogether by moving the functionality of auxiliary unit 70 into the tracker body. In most cases, auxiliary unit 70 is attached to general purpose computer 80 . Application software loaded onto general purpose computer 80 may provide application capabilities such as reverse engineering. It is also possible to eliminate general purpose computer 80 by building its computing capability directly into laser tracker 10 . In this case, a user interface, possibly providing keyboard and mouse functionality is built into laser tracker 10 . The connection between auxiliary unit 70 and computer 80 may be wireless or through a cable of electrical wires. Computer 80 may be connected to a network, and auxiliary unit 70 may also be connected to a network. Plural instruments, for example, multiple measurement instruments or actuators, may be connected together, either through computer 80 or auxiliary unit 70 .
The laser tracker 10 may be rotated on its side, rotated upside down, or placed in an arbitrary orientation. In these situations, the terms azimuth axis and zenith axis have the same direction relative to the laser tracker as the directions shown in FIG. 1 regardless of the orientation of the laser tracker 10 .
In another embodiment, the payload 15 is replaced by a mirror that rotates about the azimuth axis 20 and the zenith axis 18 . A laser beam is directed upward and strikes the mirror, from which it launches toward a retroreflector 26 .
Sending Commands to the Laser Tracker from a Distance
FIGS. 3A-3E , 4 A- 4 C, and 5 A- 5 D demonstrate sensing means by which the operator may communicate gestural patterns that are interpreted and executed as commands by exemplary laser tracker 10 . FIGS. 3A-3E demonstrate sensing means by which the operator communicates gestural patterns that exemplary laser tracker 10 interprets using its tracking and measuring systems. FIG. 3A shows laser tracker 10 emitting laser beam 46 intercepted by retroreflector target 26 . As target 26 is moved side to side, the laser beam from the tracker follows the movement. At the same time, the angular encoders in tracker 10 measure the angular position of the target in the side-to-side and up-down directions. The angular encoder readings form a two dimensional map of angles that can be recorded by the tracker as a function of time and analyzed to look for patterns of movement.
FIG. 3B shows laser beam 46 tracking retroreflector target 26 . In this case, the distance from tracker 10 to target 26 is measured. The ADM or interferometer readings form a one-dimensional map of distances that can be recorded by tracker 10 as a function of time and analyzed to look for patterns of movement. The combined movements of FIGS. 3A and 3B can also be evaluated by laser tracker 10 to look for a pattern in three-dimensional space.
The variations in angle, distance, or three-dimensional space may all be considered as examples of spatial patterns. Spatial patterns are continually observed during routine laser tracker measurements. Within the possible range of observed patterns, some patterns may have associated laser tracker commands. There is one type of spatial pattern in use today that may be considered a command. This pattern is a movement away from the surface of an object following a measurement. For example, if an operator measures a number of points on an object with an SMR to obtain the outer diameter of the object and then moves the SMR away from the surface of the object, it is clear that an outer diameter was being measured. If an operator moves the SMR away from the surface after measuring an inner diameter, it is clear that the inner diameter was being measured. Similarly, if an operator moves an SMR upward after measuring a plate, it is understood that the upper surface of the plate was being measured. It is important to know which side of an object is measured because it is necessary to remove the offset of the SMR, which is the distance from the center to the outer surface of the SMR. If this action of moving the SMR away from an object is automatically interpreted by software associated with the laser tracker measurement, then the movement of the SMR may be considered to be a command that indicates “subtract the SMR offset away from the direction of movement.” Therefore, after including this first command in addition to other commands based on the spatial patterns, as described herein, there is a plurality of commands. In other words, there is a correspondence between a plurality of tracker commands and a plurality of spatial patterns.
With all of the discussions in the present application, it should be understood that the concept of a command for a laser tracker is to be taken within the context of the particular measurement. For example, in the above situation in which a movement of the retroreflector was said to indicate whether the retroreflector target was measuring an inner or outer diameter, this statement would only be accurate in the context of a tracker measuring an object having a circular profile.
FIG. 3C shows laser beam 46 tracking retroreflector target 26 . In this case, retroreflector target 26 is held fixed, and tracker 10 measures the three-dimensional coordinates. Certain locations within the measurement volume may be assigned special meanings, as for example when a command tablet, described later, is located at a particular three-dimensional position.
FIG. 3D shows laser beam 46 being blocked from reaching retroreflector target 26 . By alternately blocking and unblocking laser beam 46 , the pattern of optical power returned to tracker 10 is seen by the tracker measurement systems, including the position detector and the distance meters. The variation in this returned pattern forms a pattern as a function of time that can be recorded by the tracker and analyzed to look for patterns.
A pattern in the optical power returned to the laser tracker is often seen during routine measurements. For example, it is common to block a laser beam from reaching a retroreflector and then to recapture the laser beam with the retroreflector at a later time, possibly after moving the retroreflector to a new distance from the tracker. This action of breaking the laser beam and then recapturing the laser beam may be considered to be a simple type of user command that indicates that the retroreflector is to be recaptured after it is moved to a new position. Therefore, after including this first simple command in addition to other commands based on the temporal variation in optical power, as described herein, there is a plurality of commands. In other words, there is a correspondence between a plurality of tracker commands and a plurality of patterns based on variations in optical power received by a sensor disposed on the laser tracker.
A change in optical power is often seen during routine measurements when the laser beam is blocked from returning to the laser tracker. Such an action may be interpreted as a command that indicates “stop tracking” or “stop measuring.” Similarly, a retroreflector may be moved to intercept a laser beam. Such simple actions might be interpreted as commands that indicates “start tracking” These simple commands are not of interest in the present patent application. For this reason, commands discussed herein involve changes in optical power that include at least a decrease in optical power followed by an increase in optical power.
FIG. 3E shows laser beam 46 tracking retroreflector 26 with a six degree-of-freedom (DOF) probe 110 . Many types of six-DOF probes are possible, and the six-DOF probe 110 shown in FIG. 3E is merely representative, and not limiting in its design. Tracker 10 is able to find the angle of angular tilt of the probe. For example, the tracker may find and record the roll, pitch, and yaw angles of probe 110 as a function of time. The collection of angles can be analyzed to look for patterns.
FIGS. 4A-4C demonstrate sensing means by which the operator may communicate gestural patterns that exemplary laser tracker 10 interprets using its camera systems. FIG. 4A shows cameras 52 observing the movement of retroreflector target 26 . Cameras 52 record the angular position of target 26 as a function of time. These angles are analyzed later to look for patterns. It is only necessary to have one camera to follow the angular movement of retroreflector target 26 , but the second camera enables calculation of the distance to the target. Optional light sources 54 illuminate target 26 , thereby making it easier to identify in the midst of background images. In addition, light sources 54 may be pulsed to further simplify target identification.
FIG. 4B shows cameras 52 observing the movement of retroreflector target 26 . Cameras 52 record the angular positions of target 26 and, using triangulation, calculate the distance to target 26 as a function of time. These distances are analyzed later to look for patterns. Optional light sources 54 illuminate target 26 .
FIG. 4C shows cameras 52 observing the position of retroreflector target 26 , which is held fixed. Tracker 10 measures the three-dimensional coordinates of target 26 . Certain locations within the measurement volume may be assigned special meanings, as for example when a command tablet, described later, is located at a particular three-dimensional position.
FIGS. 5A-5D demonstrate sensing means by which the operator may communicate gestural patterns that exemplary laser tracker 10 interprets by using its camera systems in combination with an active light source. FIG. 5A shows cameras 52 observing active retroreflector target 120 . Active retroreflector target comprises retroreflector target 126 onto which are mounted light source 122 and control button 124 that turns light source 122 on off. The operator presses control button 124 on and off in a prescribed pattern to illuminate light source 122 in a pattern that is seen by cameras 52 and analyzed by tracker 10 .
An alternative mode of operation for FIG. 5A is for the operator to hold down control button 124 only while gesturing a command, which might be given, for example, using side-to-side and up-down movements. By holding down control button 124 only during this time, parsing and analysis is simplified for tracker 10 . There are several ways that the tracker can obtain the pattern of movement, whether control button 124 is held down or not: (1) cameras 52 can follow the movement of light source 122 ; (2) cameras 52 can follow the movement of retroreflector 126 , which is optionally illuminated by light sources 54 ; or (3) tracking and measurement systems of laser tracker 10 can follow the movement of retroreflector 126 . In addition, it is possible for the tracker to follow retroreflector 126 in order to collect measurement data while the operator is at the same time pressing control button 124 up and down to produce a temporal pattern in the emitted LED light to issue a command to the tracker.
FIG. 5B shows cameras 52 observing light source 132 on six DOF probe 130 . Six-DOF probe 130 comprises retroreflector 136 , light source 132 , and control button 134 . The operator presses control button 134 on and off in a prescribed manner to illuminate light source 132 in a pattern seen by cameras 54 and analyzed by tracker 10 .
An alternative mode of operation for FIG. 5B is for the operator to hold down control button 134 only while gesturing a command, which might be given, for example, using side-to-side and up-down movements or rotations. By holding down control button 134 only during this time, parsing and analysis is simplified for tracker 10 . In this case, there are several ways that the tracker can obtain the pattern of movement: (1) cameras 52 can follow the movement of light source 132 ; (2) cameras 52 can follow the movement of retroreflector 136 , which is optionally illuminated by light sources 54 ; or (3) tracking and measurement systems of laser tracker 10 can follow the movement or rotation of six-DOF target 130 .
FIGS. 5A , 5 B can also be used to indicate a particular position. For example, a point on the spherical surface of the active retroreflector target 120 or a point on the spherical surface of the six-DOF probe 130 can be held against an object to provide a location that can be determined by the cameras 52 . Certain locations within the measurement volume may be assigned special meanings, as for example when a command tablet, described in reference to FIG. 12 , is located at a particular three-dimensional position.
FIG. 5C shows cameras 52 observing light source 142 on wand 140 . Wand 140 comprises light source 142 and control button 144 . The operator presses control button 144 on and off in a prescribed manner to illuminate light source 142 in a temporal pattern seen by cameras 54 and analyzed by tracker 10 .
FIG. 5D shows cameras 52 observing light source 142 on wand 140 . The operator presses control button 144 on wand 140 to continuously illuminate light source 142 . As the operator moves wand 140 in any direction, cameras 52 record the motion of wand 140 , the pattern of which is analyzed by tracker 10 . It is possible to use a single camera 52 if only the pattern of the transverse (side-to-side, up-down) movement and not the radial movement is important.
As explained above, tracker 10 has the ability to detect spatial positions, spatial patterns, and temporal patterns created by the operator through the use of retroreflector target 26 , six-DOF target 110 or 130 , active retroreflector target 120 , or wand 140 . These spatial or temporal patterns are collectively referred to as gestures. The particular devices and modes of sensing depicted in FIGS. 3A-3E , 4 A- 4 C, 5 A- 5 D are specific examples and should not be understood to limit the scope of the invention.
FIG. 6 shows flow chart 200 , which lists steps carried out by the operator and laser tracker 10 in issuing and carrying out gestural commands. In step 210 , laser tracker 10 scans continuously for commands. In other words, the tracker uses one or more of the modes of sensing shown in FIGS. 3A-3E , 4 A- 4 C, 5 A- 5 D to record positions, spatial patterns, and temporal patterns. In step 220 , the operator signals a command. This means that the operator creates a gesture by taking a suitable action on an object such as retroreflector target 26 , six-DOF target 110 or 130 , active retroreflector target 120 , or wand 140 . An appropriate action might involve movement to a particular absolute coordinate or movement to create a particular spatial or temporal pattern.
In step 230 , tracker 10 intercepts and parses the command just signaled by the operator. It intercepts the command by sensing and recording spatial and temporal information from the moving objects. It parses the command by using computing power, possibly within the tracker, to break the stream of data into appropriate subunits and identify the patterns formed by the subunits according to an algorithm. Types of algorithms that might be used are discussed hereinafter.
In step 240 , the tracker acknowledges that a command has been received. The acknowledgement might be in the form of a flashing light located on the tracker, for example. The acknowledgement might take several forms depending on whether the command was clearly received, garbled or incomplete, or impossible to carry out for some reason. The signal for each of these different conditions could be given in a variety of different ways. For example, different colors of lights, or different patterns or durations of flashes might be possible. Audible tones could also be used as feedback.
In step 250 , tracker 10 checks whether the command is garbled. In other words, is the meaning of the received command unclear? If the command is garbled, the flow returns to step 210 , where tracker 10 continues to scan for commands. Otherwise the flow continues to step 260 , where tracker 10 checks whether the command is incomplete. In other words, is more information needed to fully define the command? If the command is incomplete, the flow returns to step 210 , where tracker 10 continues to scan for commands. Otherwise the flow continues to step 270 .
In step 270 , tracker 10 executes whatever actions are required by the command. In some cases, the actions require multiple steps both on the part of the tracker and the operator. Examples of such cases are discussed below. In step 280 , tracker 10 signals that the measurement is complete. The flow then returns to step 210 , where the tracker continues to scan for commands.
FIG. 7 shows that step 220 , in which the operator signals a command, comprises three steps: step 222 —prologue, step 224 —directive, and step 226 —epilogue. The prologue and epilogue steps are optional. The directive part of the command is that part of the command that conveys the instructions to be followed. The prologue part of the command indicates to the tracker that the command is starting and the directive will soon be given. The epilogue part of the command indicates to the tracker that the command is over.
FIGS. 8-10 show two exemplary sets of gestures (“Example 1 gesture” and “Example 2” gesture) that correspond to an exemplary set of commands. The leftmost columns of FIGS. 8-10 show the exemplary set of commands. Some of these commands are taken from FARO CAM2 software. Other commands are taken from other software such as SMX Insight software or the Utilities software shipped with the FARO laser tracker. Besides these examples, commands may be taken from other software or simply created for a particular need. In each of FIGS. 8-10 , the second column shows a software shortcut in the CAM2 software, if available. An operator may press this software shortcut on the keyboard to execute the corresponding command. The third and fourth columns of FIGS. 8-10 show some spatial patterns that might be used to represent a certain command. The two dimensional spatial patterns might be sensed using methods shown in FIG. 3A , 4 A, or 5 D, for example.
For each of the gestures in the third and fourth columns in FIGS. 8-10 , the starting position is indicated with a small circle and the ending position is indicated with an arrow. The gestures in the third column of FIGS. 8-10 are simple shapes-circles, triangles, or squares. The 28 shapes shown in this column are distinguished from one another by their orientations and starting positions. In contrast, the shapes in the fourth column of FIGS. 8-10 are suggestive of the command to be carried out. The main advantage of the shapes in the third columns is that these are easier for the computer to recognize and interpret as commands. This aspect is discussed in more detail below. The main advantage of the shapes in the fourth columns is that these may be easier for the operator to remember.
FIGS. 11A-11F show some alternative spatial patterns that might be used in gestures. FIG. 11A shows single strokes; FIG. 11B shows alphanumeric characters; FIG. 11C shows simple shapes; FIG. 11D shows a simple path with the path retraced or repeated once; FIG. 11E shows a compound path formed of two or more simpler patterns; and FIG. 11F shows patterns formed of two or more letters.
FIG. 12 shows an exemplary command tablet 300 . The operator carries command tablet 300 to a convenient location near the position where the measurement is being made. Command tablet 300 may be made of stiff material having the size of a sheet of notebook paper or larger. The operator places command tablet 300 on a suitable surface and may use a variety of means to hold the target in place. Such means may include tape, magnets, hot glue, tacks, or Velcro. The operator establishes the location of command tablet 300 with the frame of reference of laser tracker 10 by touching fiducial positions 310 , 312 , and 314 with retroreflector 26 . It would be possible to use multiple command tablets in a given environment. An exemplary procedure for finding the command tablet location is discussed below.
Command tablet 300 may be divided into a number of squares. In addition to the squares for fiducial positions 310 , 312 , and 314 , there are squares for commands in FIGS. 8-10 , and other squares corresponding to target type, nest type, direction, and number. The layout and contents of exemplary command tablet 300 is merely suggestive, and the command tablet may be effectively designed in a wide variety of ways. A custom command tablet may also be designed for a particular job.
To gesture a command to laser tracker 10 , the operator touches the retroreflector to the desired square on command tablet 300 . This action by the operator corresponds to step 220 in FIG. 200 . Sensing of the action may be carried out by methods shown in FIG. 3C or 4 C, for example. If a sequence involving multiple numbers is to be entered—for example, the number 3.50 —then the squares 3, point, 5, and 0 would be touched in order. As is discussed below, there are various ways of indicating to the tracker that a square is to be read. One possibility is to wait a preset time—say, for at least two seconds. The tracker will then give a signal, which might be a flashing light, for example, indicating that it has read the contents of the square. When the entire sequence of numbers has been entered, the operator may terminate the sequence in a predetermined way. For example, the agreed upon terminator might be to touch one of the fiducial points.
Command tablet 300 may also be used with an articulated arm CMM instead of a laser tracker. An articulated arm CMM comprises a number of jointed segments attached to a stationary base on one end and a probe, scanner, or sensor on the other end. Exemplary articulated arm CMMs are described in U.S. Pat. No. 6,935,036 to Raab et al., which is incorporated by reference herein, and U.S. Pat. No. 6,965,843 to Raab et al., which is incorporated by reference herein. The probe tip is brought into contact with the squares of command tablet 300 in the same way as the retroreflector target is brought into contact with the squares of command tablet 300 when using a laser tracker. An articulated arm CMM typically makes measurement over a much smaller measurement volume than does a laser tracker. For this reason, it is usually easy to find a convenient place to mount command tablet 300 when using an articulated arm CMM. The particular commands included in command tablet 300 would be adapted to commands appropriate for the articulated arm CMM, which are different than commands for the laser tracker. The advantage of using a command tablet with an articulated arm CMM is that it saves the operator the inconvenience and lost time of setting down the probe, moving to the computer, and entering a command before returning to the articulated arm CMM.
We now give four examples in FIGS. 13-16 of how gestures may be used. FIG. 13 shows gestures being used to set a reference point for exemplary laser tracker 10 . Recall from the earlier discussion that Auto Reset is a possible option mode of a laser tracker. If the laser tracker is set to the Auto Reset option, then whenever the beam path is broken, the laser beam will be directed to the reference position. A popular reference position is the home position of the tracker, which corresponds to the position of a magnetic nest permanently mounted on the body of the laser tracker. Alternatively, a reference point close to the work volume may be chosen to eliminate the need for the operator to walk back to the tracker when the beam is broken. (Usually this capability is most important when the tracker is using an interferometer rather than an ADM to make the measurement.)
In FIG. 13 , the actions shown in flow chart 400 are carried out to set a reference point through the use of gestures. In step 420 , the operator moves the target in the pattern shown for “Set Reference Point” in FIG. 10 . The target in this case may be retroreflector 26 , for example, as shown in FIG. 3A . In step 430 , laser tracker 10 intercepts and parses the command and acknowledges that the command has been received. In this case, the form of acknowledgement is two flashes of the red light on the tracker front panel. However, other feedback such as a different color or pattern, or an audible tone may be used. In step 440 , the operator places SMR 26 into the magnetic nest that defines the reference position. Laser tracker 10 continually monitors position data of SMR 26 and notes when it is stationary. If the SMR is stationary for five seconds, tracker 10 recognizes that the operator has intentionally placed the SMR in the nest, and the tracker begins to measure. A red light on the tracker panel, for example, may be illuminated while the measurement is taking place. The red light goes out when the measurement is completed.
In FIG. 14 , the actions shown in flow chart 500 are carried out to establish the position of exemplary command tablet 300 in three-dimensional space. Recall from the earlier discussion that command tablet 300 has three fiducial positions 310 , 312 , and 314 . By touching a retroreflector target to these three positions, the position of command tablet 300 in three-dimensional space can be found. In step 510 , the operator moves the target in the pattern shown for “Initialize Command Tablet” in FIG. 9 . The target in this case may be retroreflector 26 , for example, as shown in FIG. 3A . In step 520 , laser tracker 10 intercepts and parses the command and acknowledges that the command has been received by flashing the red light twice. In step 530 , the operator holds SMR 26 against one of the three fiducial points. Laser tracker 10 continually monitors position data of SMR 26 and notes when the SMR is stationary. In step 540 , if SMR 26 is stationary for five seconds, tracker 10 measures the position of SMR 26 . In step 550 , the operator holds SMR 26 against a second of the three fiducial points. In step 560 , if SMR 26 is stationary for five seconds, tracker 10 measures the position of SMR 26 . In step 570 , the operator holds SMR 26 against the third of the three fiducial points. In step 580 , if SMR 26 is stationary for five seconds, tracker 10 measures the position of SMR 26 . Now tracker 10 knows the three-dimensional positions of each of the three fiducial points, and it can calculate the distance between these three pairs of points from these three points. In step 590 , tracker 10 searches for an error by comparing the known distances between the points to the calculated distances between the points. If the differences are too large, a signal error is indicated in step 590 by a suitable indication, which might be flashing of the red light for five seconds.
In FIG. 15 , the actions shown in flow chart 600 are carried out to measure a circle through the use of gestures. In step 610 , the operator moves the target in the pattern shown for “Measure a Circle” in FIG. 8 . The target in this case may be retroreflector 26 , for example, as shown in FIG. 3A . In step 620 , laser tracker 10 intercepts and parses the command and acknowledges that the command has been received by flashing the red light twice. In step 630 , the operator holds retroreflector 26 against the workpiece. For example, if the operator is measuring the inside of a circular hole, he will place the SMR against the part on the inside of the hole. Laser tracker 10 continually monitors position data of retroreflector 26 and notes when the SMR is stationary. In step 640 , after retroreflector 26 is stationary for five seconds, the red light comes on and tracker 10 commences continuous measurement of the position of retroreflector 26 . In step 650 , the operator moves retroreflector 10 along the circle of interest. In step 660 , when enough points have been collected, the operator moves retroreflector 26 away from the surface of the object being measured. The movement of retroreflector 26 indicates that the measurement is complete. It also indicates whether retroreflector target 26 is measuring an inner diameter or outer diameter and enables the application software to remove an offset distance to account for the radius of retroreflector 26 . In step 670 , tracker 10 flashes the red light twice to indicate that the required measurement data has been collected.
In FIG. 16 , the actions shown in flow chart 700 are carried out to acquire a retroreflector after the laser beam from laser tracker 10 has been broken. In step 710 , the operator moves the retroreflector in the pattern shown for “Acquire SMR” in FIG. 10 . The target in this case may be retroreflector 26 , for example, as shown in FIG. 4A . At the beginning of this procedure, the SMR has not acquired the SMR and hence the modes shown in FIGS. 3A-3E cannot be used. Instead cameras 52 and light sources 54 are used to locate retroreflector 26 . In step 720 , laser tracker 10 intercepts and parses the command and acknowledges that the command has been received by flashing the red light twice. At the same time, it drives the laser beam 46 toward the center of retroreflector 26 . In step 730 , tracker 10 checks whether the laser beam has been captured by retroreflector 26 . In most cases, the laser beam is driven close enough to the center of retroreflector 26 that it lands within the active area of the position detector within the tracker. In this case, the tracker servo system drives the laser beam in a direction that moves the laser beam toward the center of the position detector, which also causes the laser beam to move to the center of retroreflector 26 . Normal tracking occurs thereafter. If the laser beam is not driven close enough to the center of retroreflector 26 to land on the position detector within the tracker, then one possibility is to perform a spiral search, as shown in step 740 . Laser tracker 10 carries out a spiral search by aiming the laser beam in a starting direction and then directing the beam in an ever widening spiral. Whether or not to perform a spiral search can be set as an option with the laser tracker or the application software used with the laser tracker. Another option, which might be appropriate for a rapidly moving target, is to repeat step 720 repeatedly until the laser beam is captured by the retroreflector or until there is a timeout.
As discussed previously with reference to FIG. 7 , the operator signals a command through the use of three steps: an optional prologue, a directive, and an optional epilogue. If tracker 10 is constantly parsing data and can quickly respond when the desired pattern has been produced, then it may be possible to use the directive alone without the prologue or epilogue. Similarly, if the operator touches a position on command tablet 300 , the command should be clear to the tracker without the need for a prologue or epilogue. On the other hand, if the tracker cannot parse quickly enough to respond immediately to the patterns created by the operator, or if there is a chance that the operator might create a command pattern unintentionally, then use of a prologue, epilogue, or both may be needed.
An example of a simple prologue or epilogue is simply a pause in the movement of the target, which might be any of the targets shown in FIGS. 3A-3E , 4 A- 4 C, and 5 A- 5 D. For example, the operator may pause for one or two seconds before the start of a pattern and one or two seconds at the end of the pattern. By pausing in this way, the starting and ending positions of each gesture, indicated by circles and arrows, respectively, in FIGS. 8-10 and by circles and squares, respectively, in FIG. 11 will be more easily understood by the parsing software within the tracker or computer.
Another example of a simple prologue or epilogue is rapid blocking and unblocking of the laser beam from the tracker. For example, the operator may splay his fingers so that there is a space between each of the four digits. Then by moving his fingers rapidly across the laser beam, the beam will be broken and unbroken four times in rapid succession. Such a temporal pattern, which might be referred to as the “four finger salute”, is readily recognized by the laser tracker. The modes of sensing based on temporal variations in returned laser power are shown in FIG. 3D with a passive target and in FIGS. 5A-5C with active targets.
Besides the use of a prologue or epilogue in the gestural command, a type of prologue is also sometimes needed at the start of an action by the laser tracker. For example, in the examples of FIGS. 13-15 , there is a wait of five seconds after a command is given before the tracker measurement is made. The purpose of this wait is to give the operator time to get the retroreflector target into position before beginning the measurement. Of course, the time of five seconds is arbitrary and could be set to any desired value. In addition, it would be possible to use other indicators that the measurement should begin. For example, it would be possible to use a four-finger salute rather than a time delay to indicate readiness for measurement.
Active targets such as those shown in FIGS. 5A-D are useful in applications such as tool building and device assembly. A tool is a type of apparatus made to assist in the manufacture of other devices. In fields such as automotive and aerospace manufacturing, tools are constructed to exacting specifications. The laser tracker helps both in assembling and in checking such tools. In many cases, it is necessary to align the component elements of a tool with respect to one another. A single retroreflector target, such as retroreflector 26 , can be used to establish a coordinate system to which each element in the tool can be properly aligned. In a complicated tool, however, this can involve a lot of iterative measuring. An alternative is to mount multiple retroreflector targets on the tooling elements and then measure all of these in rapid succession. Such rapid measurement is made possible today by modern tracker technologies such as absolute distance meters and camera systems (such as components 42 , 44 ). If multiple retroreflectors are mounted directly on tooling, then it may be difficult or inefficient for an operator to use one of these retroreflectors to create gestural commands. It may be more convenient to use a wand such as 140 shown in FIG. 5C or 5 D. The operator can quickly give commands using a wand without disturbing the retroreflectors mounted on the tooling. Such a wand may be mounted on the end of a hammer or similar device to leave the operator's hands free to perform assembly and adjustment. In some cases, a separate retroreflector or six-DOF probe, like those shown in FIGS. 5A and 5B , respectively, may be needed during tool building. By adding a light source and control button to the basic SMR or six-DOF probe, the operator can issue commands in a very flexible way.
Active targets such as those shown in FIGS. 5A-D are also useful in device assembly. A modern trend is flexible assembly using laser trackers rather than automated tooling assembly. An important advantage of the tracker approach is that little advance preparation is required. One thing that makes such assembly practical today is the availability of software that matches CAD software drawings to measurements made by laser trackers. By placing retroreflectors on the parts to be assembled and then sequentially measuring the retroreflectors with a laser tracker, the closeness of assembly can be shown on a computer display using colors such as red to indicate “far away”, yellow to indicate “getting closer”, and green to indicate “close enough”. Using an active target, the operator can give commands to measure selected targets or groups of targets in ways to optimize the assembly process.
Multiple retroreflectors are often located in a single measurement volume. Examples for tool building and device assembly with multiple retroreflectors were described above. These examples showed that an active target can be particularly useful. In other cases, the ability of the laser tracker to recognize movements of multiple passive retroreflectors can be useful. For example, suppose that multiple retroreflectors have been placed on a tooling fixture such as a sheet metal stamping press and the operator wants to perform a target survey after each operation of the fixture. The survey will sequentially measure the coordinates of each target to check the repeatability of the tooling fixture. An easy way for the operator to set up the initial survey coordinates is to sequentially lift each retroreflector out of its nest and move it around according to a prescribed gestural pattern. When the tracker recognizes the pattern, it measures the coordinates of the retroreflector in its nest. It is the ability of the tracker cameras to recognize gestural patterns over a wide field of view that enables the operator to conveniently switch among retroreflectors.
As mentioned previously, there are several different types of methods or algorithms that can be used to identify gestural patterns and interpret these as commands. Here we suggest a few methods, while recognizing that a wide variety of methods or algorithms could be used and would work equally well. As explained earlier, there are three main types of patterns of interest: (1) single-point absolute position, (2) temporal patterns, and (3) movement patterns. Recognizing single-point absolute position is arguably the easiest of these three categories. In this case, the tracker simply needs to compare measured coordinates to see whether these agree to within a specified tolerance to a coordinate on the surface of command tablet 300 .
Temporal patterns are also relatively easy to identify. A particular pattern might consist of a certain number of on-off repetitions, for example, and additional constraints may be placed on the allowable on and off times. In this case, tracker 10 simply needs to record the on and off times and periodically check whether there is a match with a pre-established pattern. It would of course be possible to reduce the power level rather than completely extinguishing the light to send a signal to the tracker. Reduction in the level of retroreflected laser power could be obtained by many means such as using a neutral density filter, polarizer, or iris.
Movement patterns may be parsed in one, two, or three dimensions. A change in radial distance is an example of a one-dimensional movement. A change in transverse (up-down, side-to-side) movement is an example of two-dimensional measurement. A change in radial and transverse dimensions is an example of three-dimensional measurement. Of course, the dimensions of interest are those currently monitored by the laser tracker system. One way to help simplify the parsing and recognition task is to require that it occur within certain bounds of time and space. For example, the pattern may be required to be between 200 mm and 800 mm (eight inches and 32 inches) in extent and to be completed in between one and three seconds. In the case of transverse movements, the tracker will note the movements as changes in angles, and these angles in radians must be multiplied by the distance to the target to get the size of the pattern. By restricting the allowable patterns to certain bounds of time and space, many movements can be eliminated from further consideration as gestural commands. Those that remain may be evaluated in many different ways. For example, data may be temporarily stored in a buffer that is evaluated periodically to see whether a potential match exists to any of the recognized gestural patterns. A special case of a gestural movement pattern that is particularly easy to identify is when the command button 124 in FIG. 5A is pushed to illuminate light 122 to indicate that a gesture is taking place. The computer then simply needs to record the pattern that has taken place when light 122 was illuminated and then evaluate that pattern to see whether a valid gesture has been generated. A similar approach can be taken when the operator presses command button 134 to illuminate light 132 in FIG. 5B or presses command button 144 to illuminate light 142 in FIG. 5D .
Besides these three main patterns, it is also possible to create patterns made using a passive object or a passive object in combination with a retroreflector. For example, the cameras on the tracker might recognize that a particular command is given whenever a passive red square of a certain size is brought within one inch of the SMR.
It would also be possible to combine two of the three main patterns. For example, it would be possible to combine both the speed of movement with a particular spatial pattern, thereby combining pattern types two and three. As another example, the operator may signal a particular command with a saw tooth pattern comprising a rapid movement up, followed by a slow return. Similarly acceleration might be used. For example, a flick motion might be used to “toss” a laser beam away in a particular direction around an object.
Variations are also possible within types of patterns. For example, within the category of spatial patterns, it would be possible to distinguish between small squares (say, three-inches on a side) and large squares (say, 24 inches on a side).
The methods of algorithms discussed above are implemented by means of processing system 800 shown in FIG. 17 . Processing system 800 comprises tracker processing unit 810 and optionally computer 80 . Processing unit 810 includes at least one processor, which may be a microprocessor, digital signal processor (DSP), field programmable gate array (FPGA), or similar device. Processing capability is provided to process information and issue commands to internal tracker processors. Such processors may include position detector processor 812 , azimuth encoder processor 814 , zenith encoder processor 816 , indicator lights processor 818 , ADM processor 820 , interferometer (IFM) processor 822 , and camera processor 824 . It may include gestures preprocessor 826 to assist in evaluating or parsing of gestures patterns. Auxiliary unit processor 870 optionally provides timing and microprocessor support for other processors within tracker processor unit 810 . It may communicate with other processors by means of device bus 830 , which may transfer information throughout the tracker by means of data packets, as is well known in the art. Computing capability may be distributed throughout tracker processing unit 810 , with DSPs and FPGAs performing intermediate calculations on data collected by tracker sensors. The results of these intermediate calculations are returned to auxiliary unit processor 870 . As explained previously, auxiliary unit 70 may be attached to the main body of laser tracker 10 through a long cable, or it may be pulled within the main body of the laser tracker so that the tracker attaches directly (and optionally) to computer 80 . Auxiliary unit 870 may be connected to computer 80 by connection 840 , which may be an Ethernet cable or wireless connection, for example. Auxiliary unit 870 and computer 80 may be connected to the network through connections 842 , 844 , which may be Ethernet cables or wireless connections, for example.
Preprocessing of sensor data may be evaluated for gestures content by any of processors 812 - 824 , but there may also be a processor 826 specifically designated to carry out gestures preprocessing. Gestures preprocessor 826 may be a microprocessor, DSP, FPGA, or similar device. It may contain a buffer that stores data to be evaluated for gestures content. Preprocessed data may be sent to auxiliary unit for final evaluation, or final evaluation of gestures content may be carried out by gestures preprocessor 826 . Alternatively, raw or preprocessed data may be sent to computer 80 for analysis.
Although the use of gestures described above has mostly concentrated on their use with a single laser tracker, it is also beneficial to use gestures with collections of laser trackers or with laser trackers combined with other instruments. One possibility is to designate one laser tracker as the master that then sends commands to other instruments. For example, a set of four laser trackers might be used in a multilateration measurement in which three-dimensional coordinates are calculated using only the distances measured by each tracker. Commands could be given to a single tracker, which would relay commands to the other trackers. Another possibility is to allow multiple instruments to respond to gestures. For example, suppose that a laser tracker were used to relocate an articulated arm CMM. An example of such a system is given in U.S. Pat. No. 7,804,602 to Raab, which is incorporated by reference herein. In this case, the laser tracker might be designated as the master in the relocation procedure. The operator would give gestural commands to the tracker, which would in turn send appropriate commands to the articulated arm CMM. After the relocation procedure was completed, the operator could use a command tablet to give gestural commands to the articulated arm CMM, as described above.
FIG. 19 shows steps 1900 that are carried out in giving a gesture to communicate a command to the laser tracker according to the discussions that referenced FIGS. 3A-B , 4 A-B, and 5 A. Step 1910 is to provide a rule of correspondence between commands and spatial patterns. Step 1920 is for the user to select a command from among the possible commands. Step 1930 is for the user to move the retroreflector in a spatial pattern corresponding to the desired command. The spatial pattern might be in transverse or radial directions. Step 1940 is to project a light from the laser tracker to the retroreflector. This light may be a beam of light emitted along the optical axis of the laser tracker or it may be light emitted by an LED near a camera disposed on the laser tracker. Step 1950 is to reflect light from the retroreflector back to the laser tracker. Step 1960 is to sense the reflected light. The sensing may be done by a photosensitive array within a camera disposed on the tracker; by a position detector in the tracker, or by a distance meter within the tracker. Step 1970 is to determine the command based on the rule of correspondence. Step 1980 is to execute the command.
FIG. 20 shows steps 2000 that are carried out in giving a gesture to communicate a command to the laser tracker according to the discussions that referenced FIGS. 3C , 4 C, and 5 A. Step 2010 is to provide a rule of correspondence between commands and three-dimensional positions. Step 2020 is for the user to select a command from among the possible commands. Step 2030 is for the user to move the retroreflector to a position corresponding to the desired command, possibly by bringing the retroreflector target in contact with a command tablet. Step 2040 is to project a light from the laser tracker to the retroreflector. This light may be a beam of light emitted along the optical axis of the laser tracker or it may be light emitted by an LED near a camera disposed on the laser tracker. Step 2050 is to reflect light from the retroreflector back to the laser tracker. Step 2060 is to sense the reflected light. The sensing may be done by a photosensitive array within a camera disposed on the tracker; by a position detector in the tracker, or by a distance meter within the tracker. Step 2070 is to determine the command based on the rule of correspondence. Step 2080 is to execute the command.
FIG. 21 shows steps 2100 that are carried out in giving a gesture to communicate a command to the laser tracker according to the discussions that referenced FIGS. 3D and 5A . Step 2110 is to provide a rule of correspondence between commands and temporal patterns. Step 2120 is for the user to select a command from among the possible commands. Step 2130 is to project a light from the laser tracker to the retroreflector. This light may be a beam of light emitted along the optical axis of the laser tracker or it may be light emitted by an LED near a camera disposed on the laser tracker. Step 2140 is to reflect light from the retroreflector back to the laser tracker. Step 2150 is to sense the reflected light. The sensing may be done by a photosensitive array within a camera disposed on the tracker; by a position detector in the tracker, or by a distance meter within the tracker. Step 2160 is for the user to create a temporal pattern in the optical power received by the sensors on the laser tracker. Such a temporal pattern is easily done by blocking and unblocking a beam of light as discussed hereinbelow. Step 2170 is to determine the command based on the rule of correspondence. Step 2180 is to execute the command.
FIG. 22 shows steps 2200 that are carried out in giving a gesture to communicate a command to a six DOF laser tracker according to the discussions that referenced FIGS. 3E and 5B . Step 2210 is to provide a rule of correspondence between commands and pose of a six DOF target. Step 2220 is for the user to select a command from among the possible commands. Step 2230 is to use the six DOF laser tracker to measure at least one coordinate of a six DOF target in a first pose. A pose includes three translational coordinates (e.g., x, y, z) and three orientational coordinates (e.g., roll, pitch, yaw). Step 2240 is for the user to change at least one of the six dimensions of the pose of the six DOF target. Step 2250 is to measure the at least one coordinate of a second pose, which is the pose that results after the user has completed step 2240 . Step 2260 is to determine the command based on the rule of correspondence. Step 2270 is to execute the command.
FIG. 23 shows steps 2300 that are carried out in giving a gesture to communicate a command to the laser tracker to point the laser beam from the laser tracker to the target and lock onto the target. Step 2310 is to project light onto the retroreflector. This light may be light emitted by an LED near a camera disposed on the laser tracker. Step 2320 is for the user to move the retroreflector in a predefined spatial pattern. Step 2330 is to reflect light from the retroreflector to the laser tracker. Step 2340 is to sense the reflected light. The sensing may be done, for example, by a photosensitive array within a camera disposed on the tracker. Step 2350 is to determine the command based on the rule of correspondence. Step 2360 is to point the beam of light from the tracker to the retroreflector. Step 2370 is to lock onto the retroreflector with the laser beam from the tracker.
FIG. 24 shows steps 2400 that are carried out in giving a gesture to communicate a command to the laser tracker to point the laser beam from the laser tracker to the target and lock onto the target. Step 2410 is to project light onto the retroreflector. This light may be light emitted by an LED near a camera disposed on the laser tracker. Step 2420 is to reflect light from the retroreflector to the laser tracker. Step 2430 is to sense the reflected light. The sensing may be done, for example, by a photosensitive array within a camera disposed on the tracker. Step 2440 is to generate a predefined temporal pattern, as discussed hereinabove. Step 2450 is to determine the command based on the rule of correspondence. Step 2460 is to point the beam of light from the tracker to the retroreflector. Step 2470 is to lock onto the retroreflector with the laser beam from the tracker.
FIG. 25 shows steps 2500 that are carried out in giving a gesture to communicate a command to the laser tracker to point the laser beam from the laser tracker to the target and lock onto the target. Step 2510 is to project light onto the retroreflector. This light may be light emitted by an LED near a camera disposed on the laser tracker. Step 2520 is to measure at least one coordinate of a first pose of a six DOF target. As discussed hereinabove, the pose includes three translational and three orientational degrees of freedom. Step 2530 is to change at least one coordinate of a first pose. Step 2540 is to measure the at least one coordinate of a second pose, which is the pose that results after the at least one coordinate of the six DOF probe has been changed. Step 2550 is to determine the rule of correspondence has been satisfied. Step 2560 is to point the beam of light from the tracker to the retroreflector. Step 2570 is to lock onto the retroreflector with the laser beam from the tracker.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.
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, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | A method for optically communicating, from a user to a laser tracker, a command to control operation of the laser tracker includes steps of providing a rule of correspondence between each of a plurality of commands and each of a plurality of spatial patterns, and selecting by the user a first command from among the plurality of commands. The method further includes the steps of moving by the user, between a first time and a second time, a retroreflector in a first spatial pattern from among the plurality of spatial patterns, wherein the first spatial pattern corresponds to the first command, and projecting a first light from the laser tracker to the retroreflector. The method also includes the steps of reflecting a second light from the retroreflector, the second light being a portion of the first light, and obtaining first sensed data by sensing a third light, the third light being a portion of the second light, wherein the first sensed data is obtained by the laser tracker between the first time and the second time. The method includes also the steps of determining the first command based at least in part on processing the first sensed data according to the rule of correspondence, and executing the first command with the laser tracker. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a hydraulic pump that can be used as the pressure generator source in a pressure fluid device; more specifically, it relates to a hydraulic pump that can be used in an antilock brake system (ABS) or traction control system (TCS).
Conventional hydraulic pumps are of a variety of designs. For example, the pump disclosed in the Publication of Unexamined German Patent Application Number 3 236 536 is configured from a piston guide housed inside a housing cavity wherein a piston slides back and forth within the piston guide. This piston slides in one direction upon receipt of a drive force from the eccentric cam of the motor's drive shaft, then slides in the reverse direction upon receipt of the spring force of a piston return spring.
This hydraulic pump also includes a suction check valve and an exhaust check valve. When the piston backs up towards the eccentric cam by the spring force of the piston return spring, the exhaust check valve closes the fluid outlet line, wherein the suction check valve opens the fluid inlet line and sucks fluid into the pump chamber from the inlet line side.
A conventional hydraulic pump uses a mechanical sealing configuration around the outer circumference of the piston to seal that area between the pump chamber and the suction line side. A microscopic gap of the order of several microns occurs between the piston and the piston bore. This type of mechanical seal presents some problems as follows.
Components must be fabricated with very high precision. Moreover at high temperatures, the viscosity of the pressure fluid (for example brake fluid) decreases, causing a larger amount of fluid to leak out of the pump chamber and back into the suction line, which reduces the delivery capacity of the pump.
In using a mechanical seal configuration, since the piston is made from a very hard material such as a quenched steel, in order to prevent wear of the piston bore in which the piston slides, the piston guide which is made from a very hard material like steel must be interposed. This extra component adds to the cost of parts and to the cost of assembly.
Deviations from the manufacturing tolerances are unavoidable in the fabrication of the piston and piston bore. Selective matching of a piston to a piston bore of proper dimension to assure a clearance of several microns is required and is time and labor-consuming.
In a normal hydraulic pump, the space between the pump chamber and exit chamber is sealed by cladding two inelastic flat surfaces (the face of the piston guide and the face of the valve unit). Accordingly, the large contacted area reduces the surface pressure per unit of area of the contacted area, making it difficult to achieve a tight seal. As well, sealing effectiveness will be easily reduced by distortions and scratches in the contacted joint.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of this invention to provide a hydraulic pump which features ease-of-fabrication of the piston and piston housing bore. It is a second object of this invention to provide a hydraulic pump with fewer parts, therefore lighter and more compact. It is a third object of this invention to provide a hydraulic pump with stable fluid delivery.
This invention is a hydraulic pump comprised of a piston that slides in the axial direction inside a housing bore; a pump chamber housing piston return springs and being made at one end of the piston; a piston drive mechanism arranged in a housing chamber made at the other end of the piston; an inlet valve, arranged inside the pump chamber, that opens and closes a suction passage bored inside the piston; and an outlet valve set on the downstream side of the pump chamber, wherein the housing bore is made inside of a housing and the piston is inserted inside the housing bore. Two elastic sealing materials are interposed between the outer circumference of the piston and housing bore to seal that area between the pump chamber and the inlet passage and that area between the inlet passage and the housing chamber. The cross section surface of at least the seal positioned between the pump chamber and inlet passage is approximately a convex surface.
Further, in the hydraulic pump of this invention, the housing bore is made to be of non-uniform diameter over its length; wherein the piston is housed inside a small-diameter bore, and an outlet valve is housed inside a large-diameter bore; and wherein the end face of the outlet valve is pressed to make rim contact to the stepped face formed at the interface between the large-diameter, bore and the small-diameter bore, to seal the area between the pump chamber and the exit chamber.
Moreover, in the hydraulic pump of this invention, the outlet valve comprises a plug, arranged on the side exposed to the atmosphere, and containing a sealing material, mounted on the stepped face around the outer circumference of the exit chamber, that seals the area between the atmosphere side of the outlet valve and the exit chamber; a valve seat, arranged on the pump chamber side and supported by the plug; springs housed inside the valve chamber between the plug and valve seat; and a valve body energized by the springs and seated inside the valve ring of the valve seat; wherein a fluid passage is made on the plug side of the valve seat to connect the valve chamber and the exit chamber, and the sealing material is supported by a washer sandwiched between the plug and the valve seat.
Accordingly, this invention as explained above is effective as follows.
The hydraulic pump of this invention has two seals interposed around the external circumference of the piston which provide a good seal between the piston and the housing bore. At the same time, these seals enable the piston to be supported at a suitable gap from the housing bore. Thus, the piston made from a hard material can be housed directly inside the housing bore by imposing a relatively soft material, without the use of a piston guide formed from a very hard material as employed in conventional hydraulic pumps. Accordingly, there are fewer parts, and a lighter, more compact pump can be produced at lesser cost.
The clearance and the tolerance between the external surface of the piston and the housing bore can be fairly large; therefore the requirement for machining precision for these parts can be relaxed. Also, selective matching of the piston to the housing bore of the right dimensions is not required, and fabrication costs will be reduced.
The delivery capacity of the hydraulic pump is retained even at high temperatures.
The cross section surface of one of the two seals, specifically that seal between the inlet passage and the pump chamber has approximately a convex texture. This reduces the resistance to the sliding piston. Moreover, it prevents the lip of the seal from biting into the gap between the housing bore and the piston surface.
The angled rim of the outlet valve is passed to make rim contact to the stepped face of the housing bore, thus forming a seal between the pump chamber and the exit chamber. Since the contacted area of the seal is smaller than in conventional pumps, the surface pressure per unit area of the contacted surface becomes larger, creating a better seal and preventing a loss of sealing effectiveness caused by distortions or scratches in the contacted area.
The O-ring mounted externally around the plug is sandwiched by a thin plate washer on the exit chamber side, which enables the overall length of the plug to be shortened.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and the attendant advantages of the present invention will become readily apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:
FIG. 1 is a longitudinal diagram of the hydraulic pump of this invention as embodied in Example 1;
FIG. 2 is an enlarged diagram of the pump chamber; and
FIG. 3 is a longitudinal diagram to explain the operation of the hydraulic pump.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An example of this invention is explained below with reference to the attached figures.
An example of a hydraulic pump configuration is shown in FIG. 1. The hydraulic pump comprises a piston 20, stroking in the axial direction, housed directly inside the small-diameter bore 11a of a housing bore 11 bored step wise of non-uniform diameter inside the housing 10; a drive mechanism which drives the piston 20 in the axial direction; a pump chamber 12, inside the housing bore 11, housing piston return springs 30; and two valve arrangements positioned on either side of the pump chamber 12.
The housing bore 11 houses, in sequence from the base end, the piston 20, the piston return springs 30, a valve seat 40, and a plug 50. A screw threaded member 60 clamps the plug 50 against the valve seat 40.
As shown in FIG. 1, an inlet passage 13 is connected to the small-diameter bore 11a, and an outlet passage 14 to the large-diameter bore 11b of the housing bore 11.
The piston 20 has a bore 21 extending along the axial center of the piston for a fixed distance from one end of the piston. The bore 21 is connected to the injection passage 22 bored radially to the outer circumference of the piston 20. The inlet passage 13, the injection passage 22 connected to the inlet passage 13, and the bore 21 form a suction passage which feeds the pressure fluid to the pump chamber 12.
Two ring-shaped seals 23,24, molded from an elastic material, are fitted in respective grooves around the outer circumference of the piston 20 on either side of the injection passage 22. Seal 23 is combined with a backup ring 25. Seal 23 seals the area around the outer surface of the piston 20 between the inlet passage and the pump chamber 12. The other seal 24 seals the area around the outer surface of the piston 20 between the inlet passage and the housing chamber 17 which houses the eccentric cam 91.
It is preferable that the cross section surface of seal 23, sealing that space between the inlet passage and the pump chamber 12 which generates a high pressure, be approximately a convex surface. This type of cross section surface provides less resistance to the sliding piston than does a circular surface like an O-ring or a square-wave surface. Moreover, this shape prevents the lip of the seal 23 from biting into the microscopic gap formed around the circumference between the housing bore 11 and the piston 20, thus preventing any damage to the lip. A back up ring 25 made of polytetraflouroethylene, known as Teflon set adjacent to the seal 23 provides further protection against the lip of the seal 23 biting into the gap.
One end (the top end in FIG. 1) of the piston 20, housed directly inside the small-diameter bore 11a of the housing bore 11, abuts the outer perimeter of an eccentric cam 91 mounted to be eccentric to the center of rotation of the motor drive shaft 90. The piston 20 slides in any one direction only to a distance equal to twice the degree of eccentricity. The piston 20 receives the spring force of the piston return springs 30, compressed between the piston and the valve seat 40, which constantly energize the piston 20 in the direction to abut the eccentric cam 91.
As shown in FIG. 2, the valve seat 40 housed in the large-diameter bore 11b of the housing bore 11 is a cylindrical body with an external diameter smaller than the inner diameter of the large-diameter bore 11b. On one end (top side in FIG. 2) of the valve seat, a ring-shaped angled rim 41 is pressure seam welded to the stepped face 11c of the housing bore 11. This angled rim 41 maintains a good seal while also dividing the pump chamber 12 from the exit chamber 15. The cladding force of the angled rim 41 and the stepped face 11c is adjusted by the compressive force of the screw threaded member 60 screwed into the large-diameter bore 11b of the housing cavity 11.
The volume of the pump chamber 12, separating the piston 20 and the valve seat 40, increases or decreases as a function of the sliding piston. However, the volume of the exit chamber 15, made around the circumference between the inner wall of the large-diameter bore 11b and the exterior circumference of the valve seat 40, remains constant regardless of the position of the piston.
The other end (bottom side in FIG. 2) of the valve seat 40 comprises a small-diameter segment 42 made around the exterior of the valve seat. A plug 50 is fitted on the exterior of the segment 42 with the use of a washer 51. A slit 43, opened on the other end of the valve seat 40, maintains constant passage between the exit chamber 15 and the valve chamber 16 molded on the interior of the plug 50. The atmosphere side of the exit chamber 15 is sealed by the O-ring 61 set between the outer circumference of the plug 50 and the washer 51. The O-ring 61 can be inserted into a groove made around the outer circumference of the plug 50, but in this case, the overall length of the plug 50 must be lengthened by an amount equal to the width of the groove. However, the design of this example is advantageous in that since the O-ring is sandwiched by a thin plate washer 51 on the exit chamber 15 side, the overall length of the plug 50 can be shortened.
The pump chamber 12 has an inlet valve 70 and an outlet valve 80 fitted on the upstream side and downstream side respectively. As shown in the enlarged diagram of FIG. 2, the inlet valve 70 comprises valve ring 26 made at the inlet of the bore 21 of the piston 20 facing the pump chamber 12; a valve body 71 that sits on the valve ring 26, and springs 72 that receive the reactive force from the valve seat 40 and bias the valve body 71 in the direction to close the valve. The outlet valve 80 comprises a valve ring 44 made along the axial center of valve seat 40 facing the valve chamber 16, a valve body 81 that sits on the valve ring 44, and springs 82 compressed between the plug 50 and the valve body 81.
As shown in FIG. 1, the inlet valve 70 opens and closes the pressure fluid line connecting the injection passage 22 and the pump chamber 12; the outlet valve 80 opens and closes the pressure fluid line connecting the pump chamber 12 and the exit chamber 15.
In a conventional hydraulic pump, housing a piston 20 made from a hard material directly inside a housing cavity 11 (small-diameter bore 11a) made from a soft material such as an aluminum alloy would cause severe erosion of the housing bore 11 (small-diameter bore 11a) as the outer surface of the piston 20 slides and rubs against its inner surface; accordingly a piston guide made from a very hard material is inserted to envelop the piston.
This invention enables the piston 20 made from a hard material to be housed directly inside the housing bore 11 (small-diameter bore 11a) made from a soft material without the use of a hard piston guide. Rather, the piston 20 is separated from the housing bore 11 (small-diameter bore 11a) and supported by seals 23, 24 formed from elastic material and mounted around the outer circumference of piston 20, that seal the space between the pump chamber 12 and the inlet passage, and the space between the inlet passage and the housing chamber 17 respectively.
In other words, during the operation of the piston 20, to be discussed below, the piston 20 slides inside the housing bore 11 (small-diameter bore 11a) by means of the seals 23, 24, wherein the outer surface of the piston 20 barely, if at all, touches the inner surface of the housing bore 11, and the force of any contact is minimal. This eliminates abrasion and erosion of the relatively soft housing bore 11 (small-diameter bore 11a) caused by direct contact with the hard piston 20.
The operation of the hydraulic pump is explained below.
FIG. 3 shows the state in which the piston 20 has reached the upper dead end. Here, the piston return springs 30 urge the piston 20 towards the eccentric cam 91; the end face of the piston 20 abuts the perimeter of the eccentric cam 91, which regulates the backup position of the piston.
The inlet valve 70 set on the upstream side of the pump chamber 12 is closed to block passage between the inlet passage and the pump chamber 12; as well, the outlet valve 80 set on the downstream side of the pump chamber 12 is also closed to block passage through the pressure fluid line between the pump chamber 12 and the exit chamber 15.
In this state, if the motor, not shown in the figures, is started, the motor's drive shaft 90 rotates and turns the eccentric cam 91. As the eccentric cam 91 rotates, the regulated backup position of the piston 20 shifts towards the motor drive shaft 90, wherein the piston 20 receives the spring force of the piston return springs 30 and the piston backs up from the position in FIG. 3 to the lower dead end position as shown in FIG. 1.
As the piston 20 backs up, the capacity of the pump chamber 12 gradually expands, creating a vacuum pressure within the pump chamber 12. This vacuum pressure acts to close the outlet valve 80 and open the inlet valve 70; wherein the pressure fluid is sucked from the inlet passage 13 and into the pump chamber 12 via the injection passage 22, the bore 21, and the inlet valve 70.
When the eccentric cam 91 continues to rotate, as the reversing piston 20 goes beyond the lower dead point, the piston 20 switches direction to slide in the direction to compress the volume of the pump chamber 12, and advances forward from the state shown in FIG. 1 to that shown in FIG. 3.
As the piston 20 resists the force of the piston return springs 30 and advances forward, the pressure within the pump chamber 12 starts to rise; this increase in pressure acts to close inlet valve 70 and open the outlet valve 80; whereupon the pressure fluid within the pump chamber 12 is delivered out of the open outlet valve 80, through the exit chamber 15, and into the outlet passage 14. The pressure fluid continues to be delivered as the suction and delivery processes are repeated.
It is readily apparent that the above-described has the advantage of wide commercial utility. It should be understood that the specific form of the invention hereinabove described is intended to be representative only, as certain modifications within the scope of these teachings will be apparent to those skilled in the art.
Accordingly, reference should be made to the following claims in determining the full scope of the invention. | A hydraulic pump including a housing having a housing bore with a piston sliding in an axial direction in the bore and a pump chamber being defined in cavity adjacent one end of the piston. A piston drive mechanism is provided in a housing chamber defined in the bore adjacent the other end of the piston. Piston return springs are mounted in the pump chamber biasing the piston towards the piston drive mechanism. An inlet valve is arranged in the pump chamber opening and closing an axial bore in the piston connected to an inlet passage. An outlet valve is set on a downstream side of the pump chamber opening and closing an outlet passage. Two elastic seal members are mounted around a circumference of the piston respectively sealing an area between the pump chamber and the inlet passage and an area between the inlet passage and the housing chamber. | 5 |
FIELD OF THE DEVICE
The device relates to a head for applying fiber composite material to an application surface in which the individual lanes of fiber composite material are each driven by a drive roll that includes a cutter for the composite material and an ejector mechanism for displacing the leading end of the cut tow material away from the surface of the drive roll.
BACKGROUND
Composite lay-up machines are well known in the art. Such machines can be divided into two basic types, fiber placement machines that lay bundles of individual fibers onto a surface, and tape laying machines that apply fiber composite material in the form of a wide tape onto a surface. If the surface that receives the fiber composite material is fairly continuous, and does not have a lot of contour, a tape laying machine is normally used. If the surface is highly contoured or discontinuous because of the presence of openings in the surface, a fiber placement machine is normally used.
SUMMARY
A fiber placement head for fiber placement utilizes individual roller sets comprising a drive roll and backup roll for each tow lane in which each drive roll has a tow cutting and restarting zone carried on the roll's circumference. Each drive roll is geared to and meshes with a back-up roll that captures the tow material in a drive roll nip that is formed therebetween. The drive roll nip receives tow from an upstream fiber path chute and delivers the tow to a downstream fiber path chute. A tow ejector foot is mounted on the drive roll immediately following each of the cutters to prevent the leading end of the cut tow from adhering to the drive roll and misfeeding into the downstream chute.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is perspective view of the fiber delivery mechanism in a fiber placement head.
FIG. 2 is a detail of a drive roll and a portion of a backup roll.
FIG. 3 is a detail view showing the drive roll in position prior to cutting the composite material.
FIG. 4 is a detail view showing the drive roll as the cutter cuts the composite material.
FIG. 5 is a detail view showing the drive roll after the cutter has cut the composite material prior to actuation of the tow ejector foot.
FIG. 6 is a detail view showing the drive roll as the tow ejector foot is actuated.
FIG. 7 is a detail view showing the tow ejector foot returned to the retracted position and the cut end of the composite material in the downstream fiber chute.
FIGS. 8 and 9 show an alternate embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a perspective view of the fiber delivery mechanism 10 in a fiber placement head. The mechanism 10 comprises a frame structure 12 which supports an upper array of drive roll assemblies 14 and lower array of drive roll assemblies 16 . Each drive roll assembly comprises a drive roll 18 and a back-up roll 20 that is half the diameter of the drive roll 18 . Each drive roll assembly 14 and 16 feeds fiber composite material along a fiber composite path or lane to the compaction roll 22 located at the front of the frame as well known in the art. The fiber composite materials in the upper and lower lanes are interleaved at the compaction roll 22 to form a continuous layer of side-by-side strips on the application surface. The compaction roll 22 is formed by a series of side by side roller segments 24 so that the outer surface of the compaction roll may adapt to the contour of the surface to which the composite material is being applied. The frame 12 also supports an upper array of restart pinch roll assemblies 26 and a lower array of restart pinch roll assemblies 28 that are positioned between the drive roll assemblies 14 and 16 , respectively, and the compaction roll 22 . The restart pinch roll assemblies 26 and 28 drive the fiber composite material to the compaction roll 22 after the material has been cut by one of the cutters on the drive roll.
FIG. 2 is a detail view of a drive roll 18 and a portion of a backup roll 20 . The drive roll 18 is mounted by bearings (not shown) on a non-rotating drive roll hub 32 that is secured to the outside frame member 12 . The drive roll 18 may be driven by a drive pinion 34 that engages the internal gear teeth 35 of a ring gear 36 that is attached to the drive roll 18 . Rotation of the drive roll 18 is transferred to the backup roll 20 by a drive transfer arrangement that drivingly couples the drive roll and the backup roll together. In the embodiment shown, external gear teeth 38 on the ring gear 36 , best seen in FIG. 3 , engage gear teeth 40 on the outside of the backup roll 20 , to positively couple the rotation of the drive roll to the backup roll. The drive roll has two cutter assemblies 48 spaced one hundred and eighty degrees apart, and a drive surface 43 is formed on the outer circumference of the drive roll following each cutter assembly as described more fully below. A tow ejector foot 66 is positioned between the cutter assembly 48 and the drive surface 43 of the drive roll. The backup roll has an anvil 80 mounted on its outer surface, and a backup drive surface 49 is formed on the outer surface of the backup roll following the anvil.
A drive roll nip 42 is formed between the drive roll 18 and the backup roll 20 . Fiber tow 44 is delivered to the drive roll nip 42 from an upstream fiber path chute 46 , and passes through the drive roll nip 42 into a downstream fiber path chute 47 . Each cutter assembly 48 is followed by a drive zone surface 43 on a first portion of the drive roll 18 that extends counterclockwise around the surface of the drive roll. The drive zone surface 43 is formed by a circumferential portion of the drive roll that has a slightly greater radius than the remaining circumference of the drive roll so that it extends further into the drive roll nip 42 . Likewise, each anvil on the backup roll 20 is followed by the backup drive surface 49 that extends partly around the circumference of the backup roll. When the drive zone surface 43 is opposite the backup drive surface 49 , fiber composite material 44 that is positioned in the drive roll nip 42 is gripped and can be driven by the rotation of the drive roll 18 and the backup roll 20 . The drive zone surface 43 may extend around an angle A that is between ninety and one hundred and thirty five degrees around the circumference of the drive roll, and in one embodiment, the drive zone surface extends for one hundred and thirteen degrees around the drive roll. A free zone surface 45 on a second portion of the drive roll follows the drive zone surface 43 . The free zone surface 45 is positioned relative to the backup roll 20 so that when the free zone surface 45 is opposite the backup roll 20 , fiber composite material 44 can be pulled freely through the drive roll nip 42 without contacting or dragging on the drive roll or the backup roll. This provides clearance for the tow to pull through the head and is sized to reduce the amount of resin from the fiber tow material that is transferred to the surface of the drive roll and the backup roll as the fiber tow is laid onto the application surface. The free zone surface 45 may extend through an angle B that is between forty-five and ninety and degrees around the circumference of the drive roll, and in one embodiment, the free zone surface 45 extends for sixty seven degrees around the drive roll.
Referring now to FIG. 3 , the cutter assembly 48 comprises a cutter retainer 50 that is attached to the drive roll 18 by suitable fasteners such as screws 51 for rapid mounting and removal. A cutter blade 52 having a knife edge 54 is mounted between the cutter retainer 50 and a cutter guide insert 56 . The cutter blade 52 has a ramp portion 58 and a spring retaining finger 60 that is formed below the ramp portion 58 . A compression spring 62 is located in a spring pocket 64 formed in the cutter blade retainer 50 , and the end of the spring 62 presses against the underside of the retaining finger 60 . A tow ejector foot 66 is positioned behind the cutter blade retainer 50 and is mounted on a pivot shaft 67 . The tow ejector foot 66 has a ramp surface 68 leading to a lobe 69 , and a return spring seat surface 70 . A compression spring 72 is mounted between the return spring seat surface 70 and another spring retaining surface (not shown) that is part of the drive roll assembly. A cam wheel 74 is mounted on a pivot 76 that is mounted on the non-rotating drive roll hub 32 . The cam wheel 74 is in a position to impact on the ramp surface 58 of the cutter blade and the ramp surface 68 of the tow ejector foot 66 as these elements rotate past the cam wheel. An anvil 80 and an anvil retainer 82 are mounted on the outer circumference of the backup roll 20 . The anvil retainer is held in place by a fastening element such as a screw 81 . FIG. 3 shows the drive roll in a position just before the cam wheel 74 impacts on the ramp surface 58 of the cutter blade 52 .
As shown in FIG. 4 , rotation of the drive roll 18 causes the cam wheel 74 to displace the cutter blade 52 against the force of the compression spring 62 , extending the knife edge 54 into the composite material 44 in the drive roll nip 42 . As the cutter blade 52 extends, the knife edge 54 cuts through the composite material 44 and shears against the edge of the anvil 80 that is mounted on the back-up roll 20 . The synchronized rotation of the drive roll 18 and the backup roll 20 ensures that the anvil 80 is always opposite the cutter 52 when the cam wheel 74 impacts the cutter.
Although the element 80 is called an anvil, it does not function as an anvil in the sense that the knife edge 54 of the cutter blade does not cut the fiber tow 44 by pressing the fiber tow against the anvil surface. A recess is formed between the anvil 80 and the anvil retainer 82 , and the knife edge 54 of the cutter blade extends into the recess as it shears the fiber tow against the edge of the anvil 80 .
FIG. 4 shows the spacing between the downstream trailing end 84 of the cut tow and the cutter blade 54 exaggerated for clarity. It will be understood that once the tow 44 has been cut, the drive wheel 18 may stop for a period of time until the next length of tow is required to be fed through the drive roll nip 42 . After the composite material 44 is cut, the application head continues to apply composite material to the application surface until all of the composite material between the compaction roll 22 and the cutter blade 52 has been laid onto the application surface.
FIG. 5 shows the drive roll in a position just after the cam wheel 74 releases the cutter blade 52 as the cam wheel begins to impact on the ramp surface 68 of the ejector foot 66 . The cutter blade return spring 62 retracts the cutter 52 into the pocket formed between the cutter block retainer 50 and the cutter guide insert 56 . With the drive wheel in this position, the leading end 86 of the upstream tow material may follow the circumference of the drive roll surface and may be adhered to the drive roll surface immediately behind the cutter blade 52 . This can be caused by tow adhesion or curl in the tow material, and may result in the leading end 86 of the tow material not entering the downstream tow chute 47 .
FIG. 6 shows the drive roll in a position in which the cam wheel 74 rides onto the ramped surface 68 of the tow ejector foot 66 and rocks the tow ejector foot relative to the pivot 67 as shown. The pivoting of the tow ejector foot 66 positively displaces the tow material 44 from the circumferential surface of the drive roll 18 and orients the leading end 86 of the tow material so that it is in alignment with the downstream fiber path chute 47 .
FIG. 7 shows the drive roll rotated to a position in which the wheel cam 74 is no longer in contact with the ramped surface 68 of the tow ejector foot 66 . The return spring 72 has returned the ejector foot 66 to the retracted position so that it is alignment with the outer circumference of the drive roll 18 , and the rotation of the drive roll 18 and the backup roll 20 has driven the leading end 86 of the tow material into the downstream tow chute 47 .
FIGS. 8 and 9 show an alternate embodiment of the invention in which the ejector foot is mounted for linear motion. The ejector foot 90 has an elongated mounting slot 91 that is mounted on a post 92 for a linear, plunging motion in a direction that is generally parallel to the motion of the cutter blade 52 . The ejector foot 90 is formed with a lower foot surface 93 and a ramp 94 that comes into contact with the cam wheel 74 . A return spring 95 that is mounted in a pocket 96 formed in the drive roll 18 engages the underside of the ejector foot 90 below the ramp 94 and maintains the ejector foot in a retracted position as shown in FIG. 8 .
FIG. 9 shows the ejector foot 90 in an extended position as a result of the ramp 94 coming into contact with the cam wheel 74 . In the extended position, the lower foot surface 93 displaces the tow material 44 from the circumferential surface of the drive roll 18 so that the tow material is in alignment with the downstream fiber path chute 47 . Arrangements other than the elongated mounting slot 91 and the post 92 may be used to mount the ejector foot 90 for linear plunging motion relative to the drive roll 18 .
Having thus described the invention, various modifications and alterations will be apparent to those skilled in the art, which modifications and alterations will be within the scope of the invention as defined by the appended claims. | A motorized head for applying fiber composite material to an application surface includes a drive roll assembly for applying fiber composite material to an application surface. The drive roll assembly includes a drive roll and a backup roll and a drive roll nip formed between the drive roll and the backup roll. At least one cutter is mounted on the drive roll for cutting fiber composite material, and an ejector mechanism is mounted on the drive roll behind the cutter mechanism. The ejector mechanism positively displaces the leading end of the cut tow material away from the surface of the drive roll to ensure that the cut tow material does not misfeed as it approaches the fiber path chute downstream from the cutter. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of U.S. patent application Ser. No. 10/310,720, filed Dec. 4, 2002, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. The Field of the Invention
The present invention relates to the design and method of use for an implant to help realign angular and rotational deformities in long bones in patients with active growth plates.
2. Related Technology
As a result of congenital deformation, traumatic injury or other causes, long bones such as the femur, tibia and humerus may grow out of alignment, causing deformity of the limb and biomechanical abnormalities. While some deformities are asymptomatic or may resolve spontaneously, it is often necessary to intervene surgically to realign these limbs. For the patients requiring surgical intervention, both osteotomy with realignment of the bone and epiphyseal stapling are currently accepted methods of treatment.
One common method of surgical bone realignment is by means of an osteotomy, or cutting of the bone, followed by realignment of the bone. In some procedures the bone is cut laterally, transverse to the longitudinal axis of the bone. Then the bone is realigned. A bone graft is then placed in the resulting wedge space. The bone and the bone graft are stabilized by orthopedic fragment fixation implants such as screws and bone plates. In an alternative osteotomy procedure, a bone wedge is removed. The bone is realigned, and similar implants are used to secure the bone. A third method of deformity correction via osteotomy is to first cut the bone, then apply an external frame attached to pins drilled through the skin and into the bone. By adjusting the frame, either intraoperatively or postoperatively, the bone is straightened.
Because osteotomy methods require a relatively large incision to create bone cuts, they are relatively invasive; they disrupt the adjacent musculature and may pose a risk to the neurovascular structures. An additional disadvantage of these procedures is the potential risk of damage to the growth plate, resulting in the disruption of healthy limb growth. Consequently, this procedure may be reserved for bone alignment in skeletally mature patients in whom the growth plates are no longer active.
One less invasive method of bone alignment involves the placement of constraining implants such as staples around the growth plate of the bone to restrict bone growth at the implant site and allow the bone to grow on the opposite side. First conceived in 1945 by Dr. Walter Blount, this method is known as epiphyseal stapling. Typically epiphyseal stapling is more applicable in young pediatric patients and adolescents with active growth plates. A staple is placed on the convex side of an angular deformity. Since the bone is free to grow on the concave side of the deformity, the bone tends to grow on the unstapled side, causing the bone to realign over time. Once the bone is aligned, the constraining implants are typically removed.
As long as the growth plate is not disturbed, this type of intervention is generally successful. However, the procedure must be done during the time that the bone is still growing, and the physiodynamics of the physis (growth plate) must not be disturbed. With proper preoperative planning and placement of the implants, the surgeon can use the implants to slowly guide the bone back into alignment.
The implants currently used in epiphyseal stapling procedures are generally U-shaped, rigid staples. The general design has essentially remained the same as those devised by Blount in the 1940's. Since these implants are rigid, they act as three-dimensional constraints prohibiting expansion of the growth plate. They are not designed to allow flexibility or rotation of the staple legs with the bone sections as the bone is realigned. Due to the constraints of these staple implants, the planning associated with the placement of the implants is overly complicated. Consequently, the surgeon must not only determine where to position the implant across the physis, but also must account for the added variables of implant stiffness, implant strength and bone-implant interface rupture.
The force associated with bone growth causes bending of these implants proportionate to their stiffness. Depending on the strength of the implant, these loads could eventually cause the implants to fracture under the force of bone realignment. This can make them difficult or impossible to remove. These same forces can also cause the implants to deform, weakening the bone-to-implant interface. This weakening may result in migration of the implant out of the bone, risking damage to the adjacent soft tissues and failure of the procedure.
SUMMARY OF THE INVENTION
The invention relates to an orthopedic bone alignment implant system that includes a guide wire, a link and bone fasteners. The guide wire serves to locate the growth plate under fluoroscopic guidance. The bone fasteners and the link function together as a tether between bone segments on opposite sides of the physis. As the bone physis generates new physeal tissue, the bone alignment implant tethers between engagers on the bone segments. This tethering principle guides the alignment of the bone as it grows.
Although applicable in various orthopedic procedures involving fracture fixation, the bone alignment implant is also applicable to the correction of angular deformities in long bones in which the physis is still active.
The distal end of the guide wire is used to locate the physis. Once its tip is placed in the physis, it is driven partly into the physis to function as a temporary guide for the link. The delivery of the implant over the guide wire assures that the link is properly placed with the bone fasteners on opposite sides of the physis. This will minimize the chance of damaging the physis throughout bone realignment. The link is then placed over the guide wire and oriented such that openings through the link for the bone fasteners are on either side of the physis. For pure angular correction, these openings would be collinear with the long axis of the bone; for rotational correction, they would be oblique to its axis.
The bone fasteners are then placed through the openings in the link and into the bone, connecting the sections of bone on opposite sides of the physis with the implant. Alternatively, guide pins can be used to help align canullated fasteners.
The implant is designed such that it partially constrains the volume of the bone growth on the side of the physis that it is placed. The implant guides the growth of new bone at the physis such that the growth direction and resulting alignment is controlled. The implant limits the semi-longitudinal translation of the bone fasteners yet allows for the bone fasteners to freely rotate with the bone segments as the angular or torsional deformity is straightened.
In some embodiments of this invention, both the link and the fasteners are rigid, but the connection between them allows for relative movement of the fasteners. In other embodiments the link is flexible allowing the fasteners to move with the bone sections. In other embodiments, the fasteners have flexible shafts allowing only the bone engager of the fasteners to move with the bone sections. In still other embodiments, both the link and the shafts of the fasteners are flexible, allowing movement of the bone sections.
BRIEF DESCRIPTION OF THE DRAWINGS
Various embodiments of the present invention will now be discussed with reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope.
FIG. 1 is an anterior view of the knee showing a genu valgum deformity (knee knocking) in the femur and the insertion of a guide wire approximately parallel to the physis;
FIG. 2 is a sagittal view of that described in FIG. 1 showing the placement of the guide wire in the physis;
FIG. 3 is an anterior view of the knee showing the placement of a link and drill guide over the guide wire and the use of the guide to place two guide pins for fasteners on opposite sides of the physis;
FIG. 4 is a sagittal view of the placement of the link described in FIG. 3 showing the position of the two guide pins on opposite sides of the physis;
FIG. 5 is an alternative method of applying the link over the guide wire in which the link is placed first, then the fasteners are placed through the openings in the link;
FIG. 6 is a sagittal view of the link placement also shown in FIG. 5 ;
FIG. 6A is a top plan view of the link shown in FIG. 6 ;
FIG. 7 is an anterior view showing an alternative method of drilling of holes in the bone over the guide pins to prepare the bone for the fasteners;
FIG. 8 is an anterior view of the link showing the placement of the fasteners through the link and into the bone segments;
FIG. 9 is a sagittal view of the fasteners and link described in FIG. 8 ;
FIG. 10 is an anterior view as seen after the physeal tissue has grown and the bone alignment implant assembly has been reoriented as the bone is realigned;
FIG. 11 is a sagittal view of the bone alignment implant placed on a rotational deformity;
FIG. 12 is the same sagittal view described in FIG. 12 after the rotational deformity has been corrected;
FIG. 13 is a perspective view of a threaded fastener;
FIG. 14 is a perspective view of a barbed fastener;
FIG. 15 is a perspective view of an alternative embodiment of the bone alignment implant with rigid link and fasteners, with joints allowing restricted movement between them;
FIG. 16 is a perspective view of an alternative embodiment of the bone alignment implant showing a flexible midsection of the link with rigid material surrounding the openings;
FIG. 17 is a perspective view of an alternative embodiment of the bone alignment implant showing a flexible midsection of the link made from a separate flexible member with rigid material surrounding the openings;
FIG. 18 is a perspective view of an alternative embodiment of the bone alignment implant showing flexible woven material throughout the body of the link with reinforcement grommets surrounding the openings;
FIG. 19 is a perspective view of an alternative embodiment of the bone alignment implant showing the link made from a flexible band of material;
FIG. 20 is a perspective view of an alternative embodiment of the bone alignment implant showing the link made from a flexible ring of braided material that is joined in the midsection, forming two openings;
FIG. 21 is a side view of an alternative embodiment of the bone alignment implant showing bone fasteners that have flexible shaft sections;
FIG. 22 is a side view of an alternative embodiment of the bone alignment implant showing two barbed bone fasteners attached to a flexible link; and
FIG. 23 is a side view of an alternative embodiment of the bone alignment implant showing one barbed bone fastener and one threaded bone fastener connected to a flexible link.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 , a schematic anterior view of the human knee joint is depicted in which a distal femur 10 is proximal to a proximal tibia 5 and a proximal fibula 6 . A distal femoral physis 1 , or growth plate, separates a distal epiphyseal section 3 from a proximal metaphyseal section 2 of the distal femur 10 . Likewise a proximal tibial physis 1 ′ separates a proximal epiphyseal section 3 ′ from a metaphyseal section 2 ′ of the proximal tibia 5 and a proximal fibula physis 1 ″ separates a proximal epiphyseal section 3 ″ of a proximal fibula 6 from a metaphyseal section 2 ″ of the proximal fibula 6 . Although the invention described herein is adaptable to nearly all of the long bones in the body, only the example of correcting one type of an angular deformity in the distal femur will be described in detail. The principles described herein can be adapted to other deformities and other bones such as the tibia, fibula, humerus, radius and ulna.
By example, an angular deformity 4 in the femur 10 known as genu valgum or knock-knee is shown in FIG. 1 . The angular deformity 4 is the angle between a pretreatment longitudinal axis 12 of the femur 10 and a post treatment projected longitudinal axis 13 of the femur 10 . A bone alignment implant will be placed on the medial side of the femur 10 . In this case, the medial side of the femur 10 is curved in a convex arc. Hence, this side of the deformity is called a convex side 16 because the angular deformity 4 bends the femur 10 in a curve that is angled away from or convex with respect to the medial side. A concave side 17 is on the opposite side of the femur 10 . Likewise, the angular deformity 4 is angled towards the concave side 17 .
A guide wire 8 , as shown in FIG. 1 , is used to locate the physis and guide the bone alignment implant to the surgical site. The guide wire 8 comprises a long axis 11 , a distal section 9 that is shaped to fit into the physeal tissue, and a periphery 14 that is typically a constant size and shape. In this case, the shape of the guide wire 8 along the long axis 11 is essentially cylindrical so the shape of the periphery 14 is round and does not change except for in the distal section 9 . However, the periphery 14 can be a variable cross-section that changes shape or size along the length of the long axis 11 .
In this example, the long axis 11 of the guide wire 8 is placed into and approximately parallel with the physis 1 and is aligned approximately in the same plane as the angular deformity 4 . As shown in FIG. 1 , the distal section 9 of the guide wire 8 is partly inserted into the physis 1 . Since the cartilaginous physis 1 is of less density than the surrounding bone, the surgeon can either poke the distal section of the guide wire 8 into the bone until the physis 1 is located, or the surgeon can use fluoroscopic x-ray (not shown) or other bone density detection means (not shown) to determine the location of the physis 1 relative to the distal section of the guide wire 8 to place the guide wire 8 in a direction that is approximately parallel with the physis 1 .
FIG. 2 is a sagittal view approximately perpendicular to the anterior view described in FIG. 1 . For reference, a patella 7 is shown on the anterior side of the femur 10 and tibia 5 . For clarity, in this example the guide wire 8 is straight and has a constant round outer periphery 14 . Consequently, only the outer periphery 14 of the guide wire 8 is shown and appears as a circle in FIG. 2 . FIG. 2 shows the placement of the guide wire 8 in the physis between the femoral metaphyseal section 2 and the distal femoral epiphyseal section 3 . This is the preferred placement of the guide wire 8 . The guidewire 8 is used to locate an area in the physis that will eventually be bridged by the bone alignment implant 9 that will tether between two sections of the bone. In FIG. 2 , the two sections of bone that will be tethered by the bone alignment implant 9 are the distal femoral proximal epiphyseal section 3 and the femoral metaphyseal section 2 .
FIG. 3 is an anterior view of the knee showing the placement of a link 30 and a guide 20 over the guide wire 8 . The guide 20 is used to place a first guide pin 40 and a second guide pin 50 on opposite sides of the physis 1 . The link 30 has an outer periphery 34 that defines the outer material bounds of the link 30 , a bone side 37 that is the side of the link that is placed against the bone, a first opening 31 and a second opening 32 .
First, the guide 20 and link 30 are placed over the guide wire 8 by guiding the guide wire 8 over a guide opening 33 in the link 30 and the guide hole 23 in the guide 20 . Then the first guide pin 40 is driven through a first hole 21 in the guide 20 and through the first opening 31 in the link 30 into the metaphyseal bone 2 , and the second guide pin 50 is driven through a second hole 22 in the guide 20 and the second opening 32 in the link 30 into the distal epiphyseal section 3 . Once the first guide pin 40 and the second guide pin 50 are placed, the guide 20 is removed.
FIG. 4 is a sagittal view of the placement of the link 30 described in FIG. 3 . The position of the first guide pin 40 is through the first opening 31 in the link 30 . The position of the second guide pin 50 is through the second opening 32 in the link 30 . The guide pin 40 and guide pin 50 are on opposite sides of physis 1 . Likewise, the first opening 31 and the second opening 32 are on opposite sides of the physis 1 .
FIG. 5 is an anterior view showing an alternative embodiment of the link 30 placed on the medial femur 10 . In this embodiment, a first set of spikes 35 and a second set of spikes 36 on the bone side 37 of the link 30 help to keep the link 30 in place prior to the placement of a first bone fastener 70 and a second bone fastener 80 . The first set of spikes 35 is positioned near the first opening 31 and the second set of spikes 36 is positioned near the second opening 32 in the link 30 . Hence, as the link 30 is placed across the physis 1 , the first set of spikes 35 contacts the metaphyseal section 2 and the second set of spikes 36 contacts the epiphyseal section 3 . In this embodiment, the first bone fastener 70 is placed though the first opening 31 in the link 30 then into the metaphyseal section 2 and the second bone fastener 80 is placed through the second opening 32 in the link 30 then into the epiphyseal section 3 .
FIG. 6 is a sagittal view of the link 30 on the femur 10 showing the location of the first set of spikes 35 near the first opening 31 on the metaphyseal section 2 side of the physis 1 and the location of the second set of spikes 36 near the second opening 32 on the epiphyseal section 3 side of the physis 1 .
As shown in FIG. 6A , link 30 can further be defined as having a top surface 150 that is opposite the bottom surface 37 . Bottom surface 37 was also previously referenced as bone side 37 in FIG. 3 . Both bottom surface 37 and top surface 150 extend between a first side edge 152 and an opposing second side edge 154 . Likewise, both bottom surface 37 and top surface 150 longitudinally extend between a first end 156 and an opposing second end 158 . A first recess 162 is centrally formed on first side edge 152 while a second recess 164 is centrally formed on second side edge 154 .
In the embodiment depicted, guide opening 33 is centrally disposed between first opening 31 and second opening 32 with guide opening 33 being smaller than openings 31 and 32 . Each of openings 31 , 32 , and 33 are aligned along a central longitudinal axis 160 that extends between first end 156 and second end 158 . Recesses 162 and 164 can be positioned on opposing sides of guide opening 33 such that a linear line 166 extending between recesses 162 and 164 intersect guide opening 33 . The length of linear line 166 extending between recesses 162 and 164 is a first width of link 30 . Linear line 166 is shown in the present embodiment as extending orthogonal to longitudinal axis 160 .
Link 30 can also be formed so that a linear line 168 can extend between side edges 152 and 154 so as to intersect with first opening 31 . Line 168 is shown extending orthogonal to longitudinal axis 160 and measures a second width of link 30 . Because of recesses 162 and 164 , the first width is smaller than the second width. A linear line 170 can similarly extend between side edges 152 and 154 so as to intersect with second opening 32 . Line 170 is shown extending orthogonal to longitudinal axis 160 and measures a third width of link 30 . The first width of link 30 is smaller than the third width.
FIG. 7 is an anterior view of the placement of the link 30 , first guide pin 40 , and second guide pin 50 as previously described in the sagittal view shown in FIG. 4 . FIG. 7 also shows a bone preparation tool 60 that can be used to prepare a bore 28 in the bone prior to the first fastener 70 or second fastener 80 placements. The bone preparation tool 60 can be a drill, tap, rasp, reamer, awl or any tool used to prepare a bore in bone tissue for a fastener. The bone preparation tool 60 is used to prepare a bore 28 on the bone near the second opening in the epiphyseal section 3 for the second fastener 80 . A bone preparation tool 60 can also be used to prepare the bone in the metaphyseal section 2 for the first fastener 70 . In the case of the example shown in FIG. 7 , the bone preparation tool 60 is placed over the second guide pin 50 , through the second opening 32 , and into the epiphyseal section 3 . However, the bone preparation tool 60 can also be placed directly through the second opening 32 without the guidance of the second guide pin 50 . The bone preparation tool 60 is used if needed to prepare the bone to receive the first fastener 70 and second fastener 80 . Once the bone is prepared, the bone preparation tool 60 is removed from the surgical site.
The first fastener 70 is then placed over the first guide pin 40 , through the first opening 31 , and into the metaphyseal section 2 . The second fastener 80 is placed over the second guide pin 50 , through the second opening 32 and into the epiphyseal section 3 . If the first guide pin 40 and second guide pin 50 are not used, the first fastener 70 is simply driven through the first opening 31 and the second fastener 80 is simply driven though the second opening 32 without the aid of the guide pins 40 and 50 .
FIG. 8 is an anterior view showing the position of a bone alignment implant 15 on the convex side 16 of the angular deformity 4 . The bone alignment implant 15 comprises the link 30 , the first fastener 70 , and the second fastener 80 . The bone alignment implant 15 functions as a tether connecting the metaphyseal section 2 and the epiphyseal section 3 . The first fastener 70 and the second fastener 80 are placed on opposite sides of the physis 1 . As the physis 1 generates new physeal tissue 90 , the physeal tissue 90 will fill in between the metaphyseal section 2 and the epiphyseal section 3 in the space subjected to the least resistance. The bone alignment implant 15 restricts the longitudinal movement between the epiphyseal section 3 and the metaphyseal section 2 on the convex side 16 of the angular deformity 4 .
FIG. 9 shows the sagittal view of that described for FIG. 8 . The bone alignment implant 15 functioning as a tether restricting the longitudinal movement between the epiphyseal section 3 and the metaphyseal section 2 .
As shown in FIG. 10 , in a patient with an active physis, the newly generated physeal tissue 90 fills in more on the side of the bone that is not tethered by the bone alignment implant 15 . Hence, a net gain 95 of physeal tissue 90 forces the bone to align in the direction of an angular correction 97 .
Select embodiments of the bone alignment implant 15 comprise the first fastener 70 having a first engager 75 , the second fastener 80 having a second engager 85 and the link 30 . The link 30 , the first fastener 70 and the second fastener 80 function together as tethers between a first engager 75 on the first fastener 70 and a second engager 85 on the second fastener 80 , guiding movement between the epiphyseal section 3 and metaphyseal section 2 of bone.
FIG. 11 and FIG. 12 show an example of using the bone alignment implant to correct a torsional abnormality between the metaphyseal section 2 and the epiphyseal section 3 . The link 30 is placed across the physis 1 at an angle 18 that is related to the amount of torsional deformity between the bone sections 2 and 3 . As the physis 1 generates new physeal tissue 90 , the bone alignment implant 15 guides the direction of growth of the bone to allow a torsional correction 98 of the bone alignment.
Different fastening devices designs that are well known in the art can be functional as fasteners 70 and 80 . The basic common elements of the fasteners 70 and 80 are seen in the example of a threaded fastener 100 in shown in FIG. 13 and a barred fastener 120 shown in FIG. 14 .
The threaded fastener 100 , and the barbed fastener 120 both have a head 73 comprising a head diameter 74 , a drive feature 72 and a head underside 71 . The drive feature in the threaded fastener 100 is an internal female hex drive feature 102 . The drive feature in the barbed fastener 120 is an external male drive feature 122 . The shape of the underside 71 of the barbed fastener 120 is a chamfer cut 124 and the underside of the threaded fastener 100 is a rounded cut 104 . The underside 71 shape of both the threaded fastener 100 and the barbed fastener 120 examples are dimensioned to mate with shapes of the first opening 31 and the second opening 32 in the link 30 .
Directly adjacent to the head 72 on both threaded fastener 100 and the barbed fastener 120 is a fastener shaft 79 with a shaft diameter 76 . Protruding from the shaft 79 is the aforementioned engager 75 with a fixation outer diameter 77 . This fixation diameter varies depending on the bone that is being treated and the size of the patient. Typically this diameter is from 1 mm to 10 mm. The shaft diameter 76 can be an undercut shaft 125 , as shown in the barbed fastener 120 , with a diameter 76 smaller than the fixation outer diameter 77 . The shaft diameter can also be a run out shaft 105 as shown in the threaded fastener 100 with a diameter 76 larger than or equal to the fixation diameter 77 . In either case, the shaft diameter 76 is smaller than the head diameter 74 . This allows fasteners 70 and 80 to be captured and not pass completely through the openings 31 and 32 in the link 30 .
In the case of the threaded fastener 100 , the engager 75 comprises at least one helical thread form 103 . Although the example of a unitary continuous helical thread 103 is shown, it is understood that multiple lead helical threads, discontinuous helical threads, variable pitch helical threads, variable outside diameter helical threads, thread-forming self-tapping, thread-cutting self-tapping, and variable root diameter helical threads can be interchanged and combined to form an optimized engager 75 on the threaded fastener 100 . The engager 75 on the barbed fastener 120 is shown as a uniform pattern of connected truncated conical sections 123 . However, it is understood that different barbed fastener designs known in the art such as superelastic wire arcs, deformable barbs, radially expandable barbs, and barbs with non-circular cross-sections can be interchanged and combined to form an optimized engager 75 on the barbed fastener 120 .
Protruding from the engager 75 at the distal end of both the threaded fastener 100 and the barbed fastener 120 is a fastener tip 78 . The fastener tip 78 can either be a smooth conical tip 126 as shown in the barbed fastener 120 , or a cutting tip 106 as shown on the threaded fastener 100 . Although a cutting flute tip is shown as the cutting tip 106 on the threaded fastener, other cutting tips designs including gimble and spade tip can be used.
In the example of the barbed fastener 120 , a canulation bore 128 passes though the head 73 , the shaft 79 , the engager 75 , and the tip 78 . This canulation bore 128 allows placement of the fasters 70 and 80 over the guide pins 40 and 50 . Although not shown on the example of the threaded fastener 100 in FIG. 13 , it is understood that the fasteners 70 and 80 , regardless of their other features, can either be of the cannulatted design shown in the barbed fastener 120 example or a non-cannulatted design as shown in the threaded fastener 100 example.
Fasteners 70 and 80 can be made in a variety of different ways using a variety of one or more different materials. By way of example and not by limitation, fasteners 70 and 80 can be made from medical grade biodegradable or non-biodegradable materials. Examples of biodegradable materials include biodegradable ceramics, biological materials, such as bone or collagen, and homopolymers and copolymers of lactide, glycolide, trimethylene carbonate, caprolactone, and p-dioxanone and blends or other combinations thereof and equivalents thereof. Examples of non-biodegradable materials include metals such as stainless steel, titanium, Nitinol, cobalt, alloys thereof, and equivalents thereof and polymeric materials such as non-biodegradable polyesters, polyamides, polyolefins, polyurethanes, and polyacetals and equivalents thereof
All the design elements of the threaded fastener 100 and barbed fastener 120 are interchangeable. Hence either of the fasteners 70 and 80 can comprise of any combination of the design elements described for the threaded fastener 100 and the barbed fastener 120 . By way of one example, the first fastener 70 can be made from a bioabsorbable copolymer of lactide and glycolide and structurally comprise an external male drive feature 122 , a run out shaft 105 , a multiple-lead, non-continuous helically threaded engager 75 , with a cutting flute tip 106 and a continuous canulation 128 . Likewise the second fastener 80 can be made from a different combination of the features used to describe the threaded fastener 100 and the barbed fastener 120 .
Although the examples of barbed connected truncated conical sections 123 and helical thread forms 103 are shown by example to represent the bone engager 75 , it is understood that other means of engaging bone can be used for the engager 75 . These means include nails, radially expanding anchors, pressfits, tapers, hooks, surfaces textured for biological ingrowth, adhesives, glues, cements, hydroxyapatite coated engagers, calcium phosphate coated engagers, and engagers with tissue engineered biological interfaces. Such means are known in the art and can be used as alternative bone engagement means for the first bone engager 75 on the first fastener 70 or the second bone engager 85 on the second fastener 80 .
Different embodiments of the bone alignment implant 15 invention allow for different means of relative movement between the two bone sections 2 and 3 . Nine embodiments of the bone alignment implant 15 are shown in FIG. 15 through FIG. 23 . These embodiments are labeled 15 A through 15 I.
In a rigid-bodies embodiment 15 A shown in FIG. 15 , both the link 30 and the fasteners 70 and 80 are rigid, but a first connection 131 and a second connection 132 between each of them allows for relative movement between the link 30 and the fasteners 70 and 80 resulting in relative movement between the bone sections 2 and 3 . In embodiments 15 B, 15 C, and 15 D of this invention shown in FIG. 16 , FIG. 17 and FIG. 18 , the link 30 is deformable allowing the fasteners 70 and 80 to move with the bone sections 2 and 3 . In embodiments 15 E and 15 F shown in FIG. 19 and FIG. 20 , the connections between the link 30 and the fasteners 70 and 80 along with the deformable link 30 allow the fasteners 70 and 80 to move with the bone sections 2 and 3 . In an embodiment 15 G shown in FIG. 21 , the fasteners 70 and 80 are deformable allowing movement of the bone sections 2 and 3 . In embodiments 15 H and 15 I shown in FIG. 22 and FIG. 23 , the fasteners 70 and 80 are fixed to a flexible link 30 .
A rigid-bodies embodiment 15 A of the bone alignment implant 15 is shown in FIG. 15 . In the rigid-bodies embodiment 15 A, the link 30 is a rigid link 130 . In the rigid bodies embodiment 15 A, the first fastener 70 is free to rotate about its axis or tilt in a first tilt direction 60 or a second tilt direction 61 and is partially constrained to move in a longitudinal direction 62 by the confines of the size of the first opening 31 and the first shaft diameter 77 , and partially constrained to move in the axial direction by the confines of the size of the first opening and the diameter 74 of the head 73 of the first fastener 70 . The first opening 31 is larger in the longitudinal direction 62 than is the shaft diameter 77 of the first fastener 70 . This allows for relative movement at the first joint 131 in a combination of tilt in the first direction 60 , tilt in the second direction 61 , and translation in the axial direction 63 .
Similar tilt and translation is achieved between the second fastener 80 and the link 30 at the second joint 132 . The second fastener 80 is also free to rotate or tilt in a first tilt direction 60 ′ or a second tilt direction 61 ′ and is partially constrained to move in a longitudinal direction 62 ′ by the confines of the size of the second opening 32 and the shaft diameter of the second fastener 80 . The second opening 31 is larger in the longitudinal direction 62 ′ than is the shaft diameter of the second fastener 80 . This allows for relative movement at the second joint 132 in a combination of tilt in the first direction 60 ′ and tilt in the second direction 61 ′ and limited translation in the axial direction 63 ′.
The combination of relative movement between the first joint and the second joint allows for relative movement between the bone sections 2 and 3 when the rigid bodies embodiment 15 A of the bone alignment implant 15 is clinically applied across an active physis 1 .
A flexible link embodiment 15 B of the bone alignment implant 15 is shown in FIG. 16 . In the deformable link embodiment 15 B, the link 30 is represented by a deformable link 230 that allows deformation of the sections 2 and 4 as the physis 1 grows in a first bending direction 64 and a second bending direction 65 . However, the maximum length between the first opening 31 and the second opening 32 of the deformable link 230 limits the longitudinal displacement 62 between the head 73 of the first fastener 70 and the longitudinal displacement 62 ′ between the head 83 of the second fastener 80 . Since the heads 73 and 83 are coupled to the respective bone engagers 75 and 85 , and the bone engagers 75 and 85 are implanted into the respective bone segments 2 and 3 , the maximum longitudinal displacement of the bone segments 2 and 3 is limited by the deformed length between the first opening 31 and second opening 32 of the link 30 , and the flexibility and length of the fasteners 70 and 80 .
Also shown in FIG. 16 is a material differential area 38 on the link 30 . The material differential area 38 is an area on the link 30 where material is either added to the link 30 or removed from the link 30 in relationship to the desired mechanical properties of a central section 39 of the link 30 . The central section 39 is made stiffer by adding material to the material differential area 38 .
The central section 39 is made more flexible by removing material from the material differential area 38 . Similarly the central section 39 is made stiffer by holding all other variables constant and decreasing the size of the guide opening 33 . The central section 39 is made more flexible by increasing the size of the guide opening 33 . Hence the desired stiffness or flexibility of the link 30 is regulated by the relative size of the material removed or added at the material differential areas 37 and 38 and the relative size of the guide opening 33 with respect to the outer periphery 34 in the central section 39 of the link 30 .
It is also understood that the relative stiffness and strength of the link 30 and structural elements such as the central section 39 is dependent on the material from which it is made. The link 30 and structural elements such as the central section 39 therein can be made in a variety of different ways using one or more of a variety of different materials. By way of example and not by limitation, the central section 39 can be made from medical grade biodegradable or non-biodegradable materials. Examples of biodegradable materials include biodegradable ceramics, biological materials, such as bone or collagen, and homopolymers and copolymers of lactide, glycolide, trimethylene carbonate, caprolactone, and p-dioxanone and blends or other combinations thereof and equivalents thereof. Examples of non-biodegradable materials include metals such as titanium alloys, zirconium alloys, cobalt chromium alloys, stainless steel alloys, Nitinol alloys, or combinations thereof, and equivalents thereof and polymeric materials such as non-biodegradable polyesters, polyamides, polyolefins, polyurethanes, and polyacetals and equivalents thereof.
FIG. 17 shows a flexible cable embodiment 15 C of the bone alignment implant 15 . The flexible cable embodiment 15 C comprises a flexible cable link 330 joined to the first fastener 70 by a first eyelet 306 on the first side 310 and joined to the second fastener 80 by a second eyelet 307 on the second side 311 . The first eyelet 306 has a first opening 331 through which the first fastener 70 passes. The second eyelet 307 has a second opening 332 through which the second fastener 80 passes. A flexible member 339 connects the first eyelet 306 to the second eyelet 307 . The flexible member 339 allows relative movement between the first eyelet 306 and the second eyelet 307 , except the longitudinal displacement 62 and 62 ′ is limited by the length between the first opening 331 and the second opening 332 . This is proportional to the length of the flexible member 339 .
The flexible member 339 is connected to the first eyelet 306 and the second eyelet 307 by means of joined connections 318 and 319 . These joined connections 318 and 319 are shown as crimped connections in this example. However, the flexible member 339 can be joined to the link 30 by other means such as insert molding, welding, soldering, penning, pressfitting, cementing, threading, or gluing them together.
FIG. 18 shows a flexible fabric embodiment 15 D of the bone alignment implant 15 . The flexible fabric embodiment 15 D comprises a flexible fabric link 430 joined to the first fastener 70 and the second fastener 80 . The flexible fabric link 430 comprises a first grommet 406 on a first side 410 and joined to the second fastener 80 by a second grommet 407 on a second side 411 . The first grommet 406 has a first opening 431 through which the first fastener 70 passes. The second grommet 407 has a second opening 432 through which the second fastener 80 passes. A flexible fabric 439 connects the first grommet 406 to the second grommet 407 . The flexible fabric 439 allows relative movement between the first grommet 406 and the second grommet 407 , except the longitudinal displacement 62 is limited by the length between the first opening 431 and the second opening 432 . A guide hole grommet 433 may be employed to reinforce the guide pin opening 33 .
The grommets function as reinforcement structures that prevent the flexible fabric from being damaged by the fasteners 70 and 80 . The grommets can be made from medical grade biodegradable or non-biodegradable materials. Examples of materials from which the grommet can be made are similar to those bioabsorbable and non-biodegradable materials listed as possible materials for the fasteners 70 and 80 .
The flexible fabric 439 comprises woven or matted fibers of spun medical grade biodegradable or non-biodegradable materials. A wide variety of materials may be used to make the flexible fabric 439 . For example, wire, fibers, filaments and yarns made therefrom may be woven, knitted or matted into fabrics. In addition, even non-woven structures, such as felts or similar materials, may be employed. Thus, for instance, nonabsorbable fabric made from synthetic biocompatible nonabsorbable polymer yarns, made from polytetrafluorethylenes, polyesters, nylons, polyamides, polyolefins, polyurethanes, polyacetals and acrylic yarns, may be conveniently employed. Similarly absorbable fabric made from absorbable polymers such as homopolymers and copolymers of lactide, glycolide, trimethylene carbonate, caprolactone, and p-dioxanone and blends or other combinations thereof and equivalents thereof may be employed. Examples of non-biodegradable non-polymeric materials from which the flexible fabric can be made include metals such as stainless steel, titanium, Nitinol, cobalt, alloys thereof, and equivalents thereof.
A band embodiment 15 E is shown in FIG. 19 in which a band 530 that is a continuous loop or band of material that functions as the link 30 . The band embodiment 15 E allows both movement at the first joint 131 and second joint 132 and allows deformation within the link 30 . The shafts 79 of the first fastener 70 and second fastener 80 are both positioned in the inside 531 of the band 530 . The band can be either a fabric band made from the same materials described for the flexible fabric 439 of the flexible fabric embodiment 15 D, or the band 530 can be a unitary, continuous loop of a given biocompatible material such as a bioabsorbable polymer, non-biodegradable polymer, metal, ceramic, composite, glass, or biologic material.
In the band embodiment 15 E, the band 530 tethers between the head 73 of the first fastener 70 and the head 83 of the second fastener 80 as the physeal tissue 90 generates and the bone is aligned. One advantage of the band embodiment 15 E is that after the desired alignment is obtained, the band 530 can be cut and removed without removing the fasteners 70 and 80 . Furthermore, as with all of the embodiments of the bone alignment device 15 A, 15 B, 15 C, 15 D, 15 F, 15 G, 15 H and 151 , the fasteners 70 and 80 can be made from a biodegradable material and left in place to degrade.
A crimped band embodiment 15 F of the bone alignment device 15 is shown in FIG. 20 . The crimped band embodiment 15 F is similar to the band embodiment 15 E in that it allows both movement at the first joint 131 and second joint 132 . The crimped band embodiment 15 F comprises a crimped band link 630 that comprises a band 632 that loops around the head 73 of the first fastener 70 and the head 83 of the second fastener 80 . However, the link 30 in the crimped band embodiment 15 F has an additional ferrule feature 631 comprising a loop of deformable material that brings a first side 634 and a second side 635 of the band together forming the first opening 31 and the second opening 32 . A bore 633 in the midsection of the ferrule 631 passes through the crimped band link 630 to form the aforementioned guide pin hole 33 .
As with the band embodiment 15 E, an advantage of the crimped band embodiment 15 F is that after the desired alignment is obtained, the band 632 can be severed across the boundaries of the first opening 31 and the boundaries of the second opening 32 . This provides a means for the crimped band link 630 to be removed without removing the fasteners 70 and 80 .
A deformable fastener embodiment 15 G is shown in FIG. 21 . The deformable fastener embodiment 15 G comprises a first deformable fastener 770 with a deformable shaft 776 , a link 30 and a second fastener 780 . The second fastener 780 may also have a deformable shaft 786 as shown in the deformable fastener embodiment 15 G. However, it may also have a nondeformable shaft. The second fastener 780 may also be in the design or material of any of the combinations of aforementioned threaded fasters 100 or barbed fasteners 120 . Likewise, the second fastener 780 can have a flexible shaft 786 , as shown in the example of the deformable fastener embodiment 15 G in FIG. 21 , and the first fastener 770 can be in the design or material of any of the combinations of aforementioned threaded fasters 100 or barbed fasteners 120 .
The flexibility of the flexible shafts 776 and 786 of the fasteners 770 and 780 can be simply a result of the material selection of the flexible shaft 776 and 786 , or can be the result of a design that allows for flexibility of the shaft. For example, the flexible shaft 776 and 786 can be manufactured from a material such as the aforementioned biocompatible polymeric materials or superelastic metallic materials such as Nitinol that would deform under the loads associated with bone alignment. The flexible shafts 776 and 786 could also be manufactured from biocompatible materials typically not considered to be highly elastic such as stainless steel, titanium, zirconium, cobalt chrome and associated alloys thereof, and shaped in the form of a flexible member such as cable, suture, mesh, fabric, braided multifilament strand, circumferentially grooved flexible shaft, filament, and yarn.
Connections 778 and 788 between the flexible shafts 776 and 786 and the associated engagers 775 and 785 of the fasteners 770 and 780 can be unitary and continuous, as is typically the case for fasteners 770 and 780 made entirely from the aforementioned biocompatible polymeric materials and superelastic metallic materials. The connections 778 and 788 can also be joined connections as is the case for flexible shafts 776 and 786 made from flexible members. Although the example of a pressfit connection is shown as the means of the connections 778 and 788 in the deformable fastener embodiment 15 G shown in FIG. 21 , these joined connections 778 and 788 can be crimped, welded, insert molded, soldered, penned, pressfit, cemented, threaded, or glued together.
Heads 773 and 783 are connected to the respective flexible shafts 776 and 786 by respective head connections 779 and 789 . These head connections 779 and 789 can also be unitary and continuous, as again is typically the case of fasteners 70 and 80 made entirely from the aforementioned biocompatible polymeric materials and superelastic metallic materials. The head connections 779 and 789 can also be joined connections, as is the case for flexible shafts 776 and 786 made from flexible members. Although the example of a pressfit connection is the means of the connections 779 and 789 in the deformable fastener embodiment 15 G shown in FIG. 21 , these joined connections 779 and 789 can also be crimped, insert molded, welded, soldered, penned, pressfit, cemented, threaded, or glued together.
Embodiments of the bone alignment implant 15 are shown in FIGS. 22 and 23 in which the first fastener 70 and second fastener 80 are fixedly joined to the link 30 that is flexible.
A paired fastener embodiment 15 H is shown in FIG. 22 in which similar designs of paired fasteners 870 and 880 are fixedly joined to a flexible link 830 by means of joined connections 831 and 832 . These joined connections 831 and 832 are shown as insert molded connections in this example in which the link is formed within the fastener by means of molding the molded fasteners 870 and 880 around the flexible link 830 . However, the paired fasteners 870 and 880 can be joined to the link 830 by other means such as crimping, welding, soldering, penning, pressfitting, cementing, threading, or gluing.
In the paired fastener embodiment 15 H, the first paired fastener 870 and the second paired fastener 880 are shown in FIG. 22 as barbed style fasteners similar to the aforementioned barbed fastener 120 . However, the paired fasteners 870 and 880 can also be similar to the aforementioned threaded fastener 100 or can comprise of any combination of the design elements described for the threaded fastener 100 and the barbed fastener 120 .
A non-paired fastener embodiment 15 I is shown in FIG. 23 in which different designs of fasteners 970 and 980 are fixedly joined to a flexible link 930 by means of joined connections 931 and 932 . These joined connections 931 and 932 are shown as insert molded connections in this example in which the link is formed within the fastener by means of molding the molded fasteners 970 and 980 around the flexible link 930 . However, the fasteners 970 and 980 can be joined to the link by other means such as crimping, welding, soldering, penning, pressfitting, cementing, threading, or gluing.
While the present invention has been disclosed in its preferred form, the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. The invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. No single feature, function, element or property of the disclosed embodiments is essential. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. The following claims define certain combinations and subcombinations that are regarded as novel and non-obvious. Other combinations and subcombinations of features, functions, elements and/or properties may be claimed through amendment of the present claims or presentation of new claims in this or a related application. Such claims, whether they are broader, narrower or equal in scope to the original claims, are also regarded as included within the subject matter of applicant's invention. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. | A method for correcting an angular deformity in a bone includes inserting a guide wire within a physis of a bone having an angular deformity, the physis extending between a first side the bone on which the guide wire is inserted and an opposing second side of the bone. The guide wire is used to guide a link to the physis. The link is then secured to the first side of the bone so that the link spans across the physis and restricts the growth of the physeal tissue of the physis on the first side of the bone. The physis is then allowed to generate more physeal tissue on the second side of the bone than on the first side of the bone so that the angular deformity of the bone is reduced. | 0 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to a prosthetic acetabular cup inserter which is particularly, although not exclusively, applicable for minimally invasive surgery (MIS) with small incisions. The inserter can also be used to orient the cup outer shell in the acetabulum and to impact it. The outer shell generally receives a polyethylene or ceramic bearing which in turn receives the spherical head of a femoral component. The invention allows the inserter to have a curved shape although the invention can be applied to inserters with a substantially axially straight shape.
[0002] WO 2004/010882 shows a surgical impactor which is intended for engagement with a threaded implant. The cup holder is provided with a collet which carries a screw thread and the collet can be opened or closed by operation of a tapered cam. The cam is resiliently biased into its operative position to open the collet to collapse which reduces or collapses a screw thread to detach the impactor from the implant.
[0003] A fundamental problem with this construction is that the cam is not forceably held in its operative position but merely relies upon a spring so that the cam can move backwards against the spring in certain circumstances thus reducing the grip on the implant. Moreover, the available area of the collet for engaging the implant is restricted by the cover which must extend over the collet to locate it in place.
[0004] Curved acetabular cup impactors/inserters/reamers are shown in U.S. Patent Publications 2003/0050645, 2003/0229356 and 2004/0153063.
[0005] Straight impactors showing devices for gripping the outer shell of the acetabular cup system are shown in U.S. Pat. Nos. 4,632,111, 5,169,399, 5,571,111, 5,540,697 and 5,954,727.
[0006] U.S. Pat. No. 4,632,111 shows apparatus for positioning a prosthetic acetabular cup within an acetabulum and relies upon an expandable elastomeric annular collar. The collar is expanded by operation of a hand retainer nut which acts on a threaded stem to provide pressure against the annular collar so that it can be compressed and its diameter increased to grip the inner surface of the cup to be implanted.
[0007] It would be very difficult to use this device where there is little available room for the surgeon to operate, especially for minimally invasive surgery (MIS) with a short incision. The present invention is intended to overcome the difficulties of both the above earlier disclosures and to provide a prosthetic acetabular cup inserter which is easier to operate.
[0008] As used herein, when referring to bones or other parts of the body, the term “proximal” means closer to the heart and the term “distal” means more distant from the heart. The term “inferior” means toward the feet and the term “superior” means towards the head. The term “anterior” means towards the front part of the body or the face and the term “posterior” means towards the back of the body. The term “medial” means toward the midline of the body and the term “lateral” means away from the midline of the body.
SUMMARY OF THE INVENTION
[0009] According to the present invention a prosthetic acetabular cup inserter includes an adjustable cup holder having a resilient ring which can be expanded to grasp the cup outer shell with which it is to be used by operation of an elongated flexible element by a tensioning device which tensions, for example, a cable which causes the resilient ring to expand.
[0010] Thus, the adjustable cup holder can be carried on an operating handle and the elongated flexible element can be operable from the handle. In a preferred embodiment, the handle is connected to the adjustable cup holder by an extension and this can be curved or substantially straight. The elongated flexible element may conveniently be carried within the extension.
[0011] In a preferred embodiment, the tension is applied to the elongated flexible element by an operating element carried on a ramp or screw thread so that rotation thereof causes lengthwise movement of the elongated flexible element.
[0012] In an alternative embodiment, the force can be applied to the elongated flexible element by a pivoted trigger mechanism, angular movement of which causes lengthwise movement of the elongated flexible element.
[0013] A device can be included for adjusting the operative length and tension of the elongate flexible element. In a preferred arrangement the trigger mechanism can include a rotatable cam which can be operated to apply the tension to the elongate flexible element.
[0014] The adjustable cup holder can include a backing member, a movable operating member and a resilient deformable member which is deformed to grasp and inner surface of the cup to be inserted when the movable operating member is moved in relation to the backing member. The resilient ring can be made from an elastomeric material and can be axially compressed to cause it to expand radially to grip the cup.
[0015] A system can be included for adjusting the operative length and tension of the elongate flexible element.
[0016] In a preferred arrangement the trigger mechanism can include a rotatable cam which can be operated to apply the tension to the elongate flexible element.
[0017] The adjustable cup holder can include a backing member, a movable operating member and a resilient deformable member which is deformed to grasp an inner surface of the cup to be inserted when the movable operating member is moved in relation to the backing member.
[0018] The resilient ring can be made from an elastomeric material and can be axially compressed to cause it to expand radially to grip the cup.
[0019] The adjustable cup holder can include a backing member and a movable operating member to which the flexible element is connected and between which the resilient ring is located so that it is axially compressed when the movable operating member is moved towards the backing member when tension is applied to the flexible element. Thus, the resiliently deformable member may be arranged to grasp the inner rim of the cup or an area adjacent thereto.
[0020] In an alternative construction the resiliently deformable member can be in the form of split ring and the movable operating member can include a tapered portion which acts against the inner surface of the ring to cause it to expand to engage and grip the cup to be inserted.
[0021] The backing member can be removably secured to the handle or extension thereof to allow the cup holder to be removed and the backing member can be provided with a system for securing it in a predetermined angular position in relation to the axis of the handle and/or extension thereof.
[0022] In the above constructions one end of the elongated flexible element can be secured to the movable operating member and the other end secured to the operating element carried on the operating handle or extension. A system can be included to apply a first tension to the flexible cable to hold the backing member and movable operating member in position in the adjustable cup holder and then to apply a second tension to cause the resilient ring to expand. The first tension can be achieved in a first position of the trigger and the second tension when the trigger is in a second position. The elongated flexible element can be made of any suitable material and in a convenient construction is in the form of a metal cable.
[0023] The invention also includes a prosthetic acetabular cup inserter as set forth above including in combination therewith one or more alternative cup holders which have different dimensions and are for use with cups of different dimensions from the first and which can be fitted in place of the first cup.
[0024] It will be appreciated that the use of such an elongated flexible element provides the designer with a wide range of possibilities due to the ability of the cable to extend around curves and corners between an operating position, for example on the handle of the device, and the adjustable cup holder, and the use of the flexible element in tension ensures a sufficiently powerful operation for the expansion of the resilient ring.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The invention can be performed in various ways and two embodiments will now be described by way of example and with reference to the accompanying drawings in which:
[0026] FIG. 1 is a side elevation of a prosthetic acetabular cup inserter but without an adjustable cup holder;
[0027] FIG. 2 is a plan view of the cup inserter shown in FIG. 1 ;
[0028] FIG. 3 is a cross-sectional side elevation of the other side of the inserter from that shown in FIG. 1 and with the adjustable cup holder in place on a prosthetic acetabular cup;
[0029] FIG. 4 is an enlarged cross-sectional elevation of part of the inserter shown in FIGS. 1 to 3 ;
[0030] FIG. 5 is a plan view of the elongated flexible element used in the construction shown in FIG. 3 ;
[0031] FIG. 6 is a pictorial isometric view from the other end of the elongated flexible element as shown in FIG. 5 ;
[0032] FIGS. 7 to 11 are pictorial isometric views showing how the various parts of the adjustable cup holder are assembled together;
[0033] FIG. 12 is an isometric view of an alternative construction of part of the adjustable cup holder;
[0034] FIG. 13 is a pictorial exploded isometric view of the various parts of another alternative construction of adjustable cup holder;
[0035] FIG. 14 is an isometric view showing the adjustable cup holder shown in FIG. 13 ready to receive the acetabular cup with which it is to be used;
[0036] FIG. 15 is another isometric view of the adjustable cup holder shown in FIG. 13 ready to receive the acetabular cup;
[0037] FIG. 16 is an isometric view of the adjustable cup holder shown in FIGS. 1 to 12 or 12 to 15 ;
[0038] FIG. 17 is a cross-sectional side elevation of part of another alternative construction;
[0039] FIG. 18 is a plan view from above of the construction shown in FIG. 17 ;
[0040] FIG. 19 is an isometric view of the construction shown in FIGS. 17 and 18 ;
[0041] FIG. 20 is a sectional side elevation of an alternative construction with an operating trigger lever in a free position and in which the handle can receive the adjustable cup holder;
[0042] FIG. 21 is a view similar to FIG. 20 of the same construction with the operating trigger lever in a position to cause a first tension to hold the adjustable cup holder in position;
[0043] FIG. 22 is a view similar to FIGS. 20 and 21 of the same construction with the operating trigger lever in a position to grasp the cup to be inserted;
[0044] FIG. 23 is a exploded isometric view of the various parts which make up an alternative construction of an adjustable cup holder;
[0045] FIG. 24 shows the parts illustrated in FIG. 23 assembled together and ready for assembly onto a shaped end piece on the handle and stem;
[0046] FIG. 25 shows the parts shown in FIGS. 23 and 24 in position and ready for rotation to a locked position;
[0047] FIG. 26 shows the parts locked in position on the handle and stem;
[0048] FIG. 27 is an isometric view of the parts shown in FIGS. 23 to 26 in position on the handle and stem and ready to receive the acetabular cup which is to be used; and
[0049] FIG. 28 is a view similar to view 27 with the acetabular cup in place on the inserter.
DETAILED DESCRIPTION
[0050] As shown in FIGS. 1 to 12 the preferred prosthetic acetabular cup inserter, according to the present invention, comprises an adjustable cup holder 1 which can be operated to grasp the cup 2 with which it is to be used from a position remote from the cup holder 1 through an elongated flexible element 3 which is in the form of a steel cable.
[0051] The adjustable cup holder 1 is carried on an operating handle 4 which can be rubberized and from which the flexible element 3 is operated. The free end of handle 4 may have a knob 6 with a striker area 6 a . The handle 4 is connected to the adjustable cup holder by a hollow extension 5 within which the flexible element 3 is carried. As will be seen from the drawings the extension is of a curved shape to assist the surgeon during surgery.
[0052] A tension force is applied to the flexible element 3 by an operating element 6 which is in the form of a grooved knob and which has a screw threaded axial bore 7 . An extended portion 8 of the knob 6 is located in a top hat shaped bearing 9 and in which it can freely rotate. The inner end of the bearing 9 is closed but has a shaped bore 10 , provided with three flats which are angularly spaced apart by 120°, and within which a shaped nipple 11 (shown in FIGS. 5 and 6 ) provided on the flexible element 3 can slide but not rotate. From FIGS. 5 and 6 it will be seen that the shaped nipple is substantially cylindrical apart from a set of three flats 12 which are angularly spaced apart by 120° and this portion of the nipple 11 also carries a screw thread which can co-operate with the screw thread in the bore 7 on the operating knob 6 . Thus, rotation of the operating knob 6 will cause the screw threaded nipple to move backwards and forwards in the screw threaded bore 7 and it is held against rotation by the flats 12 acting against the flats in shaped bore 10 in the bearing 9 . Rotational movement of the knob 6 can therefore be in a direction to create a tensional force in the flexible element 3 .
[0053] As shown in FIG. 4 , in order to facilitate location of the extended portion 8 in the bearing 9 a ring 13 is provided in a groove 14 which holds it in place when the flexible element 3 is not assembled, but which can be dismantled for cleaning.
[0054] The end of the extension 5 spaced away from the handle 4 includes a substantially conically shaped end piece 15 which is rigidly secured to the hollow extension 5 . As is best seen in FIGS. 7 and 8 the end piece 15 has a flat substantially circular bearing surface 16 which is provided with a pair of spaced apart shaped abutments 17 and which are arranged diametrically opposed to each other on each side of a bore 18 which communicates with the bore of the hollow extension 5 .
[0055] A backing member in the form of a pressure plate 19 has a shaped opening 20 adapted to fit over the abutments 17 which act to prevent plate 19 from rotating on the end piece 15 . The backing plate 19 has an outer rim 21 which is shaped and adapted to align with the outer rim 22 of the acetabular cup shell to be inserted. The inner edge of the outer rim 21 of the plate 19 is shaped to receive a resiliently deformable member in the form of a flexible ring 23 . This can be square, rectangular or circular shaped as required. The outer diameter of flexible ring 23 is very slightly less than the inner diameter of the rim 22 of the cup 2 so that it can extend over it.
[0056] The flexible ring 23 is located on a movable operating member 24 which has an outer rim 25 shaped to extend over and engage the outer rim of the ring 23 . The movable operating member 24 is also provided with a shaped opening 26 and which is of substantially the same shape and dimensions as the opening 20 in the backing member 19 .
[0057] As seen in FIG. 6 , the end of the flexible element 3 displaced from the nipple 11 carries a shaped locking head 30 which has a shaped part-circular collar 31 and a cylindrical stem portion 32 . The locking head 30 has a bore which also extends through the cylindrical portion 32 and the outer end of which is substantially rectangular. This engages with a substantially rectangular nipple 35 (and shown in FIG. 3 ) and prevents the head 30 from rotating on the element 5 . The collar 31 is shaped to locate within the abutment 17 with its flat sides 37 aligned with the edges 38 of the abutments, as will be clearly seen from FIG. 9 , and so that when the backing plate 19 is placed in position over the abutments 17 it will prevent rotation of the collar 31 on the head 30 and cylindrical extension 32 . The spring 33 engages against a shoulder 39 in the bore in the conically shaped end 15 so that the head 31 is biased outwardly from the extension 5 into the position shown in FIG. 9 .
[0058] The parts are assembled together as shown in FIGS. 7, 8 , 9 , 10 and 11 . FIG. 7 shows the end piece 15 ready to receive the flexible element 3 . This is inserted so that the end carrying the nipple 11 is pushed through the extension and handle and until it engages with the screw threaded bore 7 in the operating knob 6 . Rotation of the operating knob in the appropriate direction now causes the nipple 11 to move up the bore 7 .
[0059] With the head 30 in position, as shown in FIG. 8 , the backing plate 19 can be added by passing it over the projections 17 where it also acts to prevent rotation of the collar 31 as shown in FIG. 9 .
[0060] The movable operating member 24 is now placed in position, as indicated in FIG. 10 , and is then rotated through 90° so that its opening 26 lies at right angles to the head 31 and thus locks the assembly together, as shown in FIG. 11 .
[0061] The edge of the inner rim 25 now rests against the flexible deformable ring 23 which has been placed in position prior to the movable operating member 24 .
[0062] With the parts in the position indicated above the cup 2 to be inserted is placed over the rim of the ring 23 and the operating knob 6 is rotated appropriately which causes a tension and axial movement of the flexible element 3 thus pulling the movable operating member 24 against the resiliently deformable ring 23 so that it is compressed and is forced radially outwardly against the inner surface of the outer edge of the cup thus grasping the rim of the cup and holding it in position in relation to the inserter, as shown in FIG. 3 .
[0063] The cup can now be inserted in the acetabulum as required and the cup can also be held in this position if impaction is required.
[0064] With the cup positioned it can be easily released merely by rotating the operating knob 6 appropriately which will release the pressure on the resiliently deformable ring 23 and allow the inserter to be removed.
[0065] FIG. 12 shows an alternative embodiment in which the same reference numerals are used to indicate similar parts but in this arrangement the shaped abutments 17 are of different dimensions, one, 17 ′, being larger than the other. The shaped opening 20 is shaped to accommodate the abutments 17 to ensure that the pressure plate 19 can only be fitted in one predetermined position. This construction is for use with prosthetic cups which have a particular anatomic shape and which require insertion in a particular position in the acetabulum.
[0066] FIGS. 13, 14 and 15 show an alternative embodiment in which the same principles are employed as that set forth in FIGS. 1 to 12 but in this construction the adjustable cup holder is designed to operate with a cup 40 which has an internal groove 41 displaced inwardly from its immediate inner rim which carries a ring of depressions. With this construction the shape of the conical end 15 of the apparatus is similar to that described with regard to FIGS. 1 to 12 but the shaped head 30 on the flexible element 3 is replaced by a head carrying a pair of cylindrical abutments 42 . A backing or pressure member 43 of similar construction to but of different shape to that shown in FIG. 9 is employed and located on this is a circlip or split ring 44 which replaces the deformable ring 23 shown in FIGS. 1 to 12 . The circlip can be made of metal or any other suitable material. The removable operating member in this construction is in the form of a dished member 45 which has a conical outer wall 46 and a shaped opening 47 which is dimensioned to pass over the abutments 42 . The shape of the abutments 17 can be as shown in FIG. 12 .
[0067] The assembly is placed together in a similar manner to that described with regard to the earlier construction and the removable operating member 45 is again rotated through 90° to hold it in position. When the operating knob 60 is rotated the flexible element 3 again acts to pull the removable operating member 45 towards the backing member 43 but in this case the tapered sides of the operating member engage the inner surface 48 of circlip 44 forcing it apart. Thus, when the cup 40 is placed on the assembly operation of the flexible element 3 causes the circlip 44 to expand into the groove 41 on the cup 40 and thus hold it in position. The cup can be released by again operating the knob 6 .
[0068] As shown in FIG. 1 a guide 50 can also be provided on or adjacent the handle to assist the surgeon.
[0069] FIG. 16 shows how the rear face of the pressure plate 19 can be marked with a landmark 55 to indicate the position of a trial cup (not shown) to the definitive cup 2 to be inserted using a bistoury marking on the rim of the acetabulum. Reference numeral 56 indicates an area to position the trial cup following the anterial rim of the acetabulum. The markings are desirable for use with cups which have a particularly shaped rim.
[0070] FIGS. 17 to 19 show another alternative construction in which the same reference numerals are used to indicate similar parts to those shown in FIGS. 1 to 12 .
[0071] In this construction a trigger mechanism is employed the pivotal movement of which is used to tension the flexible element 3 . The trigger mechanism comprises an operating trigger lever 60 which is located within a slot 61 in the handle 4 and carried on a pivot pin 62 which extends transversely across the handle 4 . The trigger lever 61 has a pair of flanges 64 each of which has a bore 65 to accept one of the pivot pin 62 . The flanges 64 each have a cam surface 66 which extends around the end of the trigger lever 60 . Thus, when the lever 60 is pivoted about the pivot pin 62 the cam surfaces 66 are also rotated. Cam surfaces 66 bear against a cylindrical bearing block 67 carried on an adjustment hand wheel 68 . The hand wheel 68 has an extension 69 which locates in a bearing bore 70 provided in a handle end cap 71 .
[0072] The end of the flexible element 3 is provided with a screw threaded nipple 72 which is carried in a screw threaded bore 73 in the adjusting wheel 68 and extends through an opening 74 in the pivot pin 62 and between the cam flanges 64 .
[0073] As will be seen from FIG. 19 the handle 4 is cut away at 75 and 76 to provide an extension of the slot 61 to enable the hand wheel 68 to be rotated by the operator. The adjustable cup holder 1 can be similar to that shown in FIGS. 1 to 12 and the flexible element 3 can be attached in a similar manner, preferably however an alternate cup holder construction is used which is shown in FIGS. 19 to 28 as further described below.
[0074] To operate the trigger mechanism the trigger is first lifted to the position shown in FIG. 19 . In this position the height of the cam surface is their lowest so that there is the maximum relaxation of the flexible element 3 . This enables the cup to be placed in position on the cup holder. The lever is now rotated in an anticlockwise direction when viewed in FIG. 17 which moves the cam surfaces round their highest position which in turn forces the bearing block 67 towards the right (as shown in FIG. 17 ) thus tensioning the flexible element 3 which is connected to the bearing block 67 and the hand wheel 68 , the axial movement being accommodated in the bore 70 . The tension of the flexible element 3 is sufficient for the flexible ring 23 in the cup holder 1 to grasp the cup. The trigger mechanism can also be employed with the cup holder construction shown in FIGS. 13 to 16 .
[0075] The applied tension at the closed position of the trigger, that is in the position shown in FIG. 17 , can be adjusted by rotating the hand wheel 68 . This can be rotated on the threaded nipple 72 which will cause the nipple to move axially in either direction depending upon the direction of rotation of the hand wheel. The effect is to vary the operative length of the flexible element 3 and to increase or decrease the applied tension.
[0076] The hand wheel can thus be used when different sized cups are employed which, depending upon their dimensions, may require slightly more or less movement of the resilient ring to grasp the cup.
[0077] If required the trigger mechanism can include a locking mechanism to allow it to be locked in the position shown in FIG. 17 . This, for example, can be in the form of a simple rotating clasp indicated by reference numeral 78 and shown in broken lines in FIG. 18 .
[0078] FIGS. 20 and 22 show a construction in which the same reference numerals are used to indicate similar parts as in FIGS. 17 to 19 and the constructions of the handle 4 is generally similar to that described in FIGS. 17, 18 and 19 but the operating trigger lever can be moved to three operative positions. The operating trigger lever is indicated by reference numeral 81 and its cams, indicated by reference numeral 82 , have three operating surfaces, indicated by reference numerals 83 , 84 and 85 respectively.
[0079] FIG. 20 shows the operating trigger lever 81 in a first position where the cam surface 83 bears against the cylindrical bearing block 67 on the hand wheel 68 . In this position the flexible element can be assembled onto the handle. Before assembling the cup holder 1 to the end piece on the extension 5 the hand wheel 68 is tightened up to the cam surface 83 and the operating trigger lever 81 is then moved to the second position, as shown in FIG. 21 , and the second cam surface 84 bears against the cylindrical bearing block 67 . This cam surface is 1.5 mm lower than cam surface 83 and allows the adjustable cup holder assembly to be fitted to the end piece of the extension 5 and for the locking head 30 to be located in place.
[0080] The assembly is now ready to receive the cup with which it is to be used.
[0081] When the cup is placed in position on the adjacent cup holder 1 the operating trigger lever 81 is moved to the third position as shown in FIG. 22 . This causes cam surface 85 to engage the cylindrical bearing block 67 and thus tension the flexible element 3 . The cam surface 85 is 1 mm higher than the cam surface 84 and this provides sufficient tensioning in the flexible element 3 to compress the flexible ring 23 to cause it to expand and grasp the rim of the cup.
[0082] Due to the dimensions of the cam surface this now allows the surgeon 0.5 mm movement if he wishes to further tighten the grip on the cup by operating the hand wheel 68 .
[0083] To release the cup the operating trigger lever 81 is moved back to the position shown in FIG. 21 which allows the release of the inserter from the cup and the operating trigger lever can be moved further counterclockwise to a position shown in FIG. 20 to allow the various parts of the cup holder 1 to be released from the end piece 15 .
[0084] As described above, the construction as shown in FIGS. 17 to 21 can be used with the arrangements shown in FIGS. 7 to 15 .
[0085] FIGS. 19 to 28 show an alternative form of releasable cup holder which can not only be used with the construction shown in FIGS. 17 to 22 but also with the arrangement shown in FIGS. 1 to 8 . In this construction the releasable cup holder comprises a backing member 90 which has an outer rim 91 shaped and adapted to align with the outer rim of the acetabular cup to be inserted. The backing member 90 is adapted for use with an end piece 92 as shown in FIGS. 19, 24 , 25 and 26 . This end piece, which is rigidly secured to the hollow extension 5 , has a substantially flat circular bearing surface 93 similar to the bearing surface 16 of the construction shown in FIGS. 7 and 8 . It also has a pair of spaced apart shaped abutments 94 which are arranged diametrically opposed to each other on each side of a bore which communicated through the bore of the hollow extension 5 .
[0086] In addition to the abutments 94 the end piece 92 has a projection 95 adjacent its outer rim and best seen in FIGS. 24, 25 and 26 and a shaped locking head 30 , similar to that shown in the other constructions, is also provided.
[0087] The backing member 90 has a first radial groove 96 from which extends a ramp 97 . This terminates in a flat circumferentially extending surface 98 and leads to a second radially extending groove 99 with which is aligned a cut-out 100 .
[0088] The movable operating member 110 in this construction comprises a flanged circular plate 111 the flange 112 having a radially projecting rim 113 . A shaped opening 114 , similar to the shaped opening 26 in the construction shown in FIGS. 7 to 12 , is provided and the circular plate 111 has a projecting pin 115 .
[0089] The flexible element 120 in this arrangement is shaped to extend over the flange 112 and rest against the outer rim 113 .
[0090] This construction is assembled by placing the flexible element 120 in position on the flange 112 and pushing the operating member 110 onto the backing member 90 , at the same time engaging the pin 115 in a bore 116 in the backing member. It will be appreciated that the pin 115 aligns and holds the parts together. The assembled parts are presented to the end piece 92 as shown in FIG. 24 and then pressed against the end piece 92 as shown in FIG. 25 . The flexible element is dimensioned so that it is slightly compressed when the parts are pushed into positions as shown in FIG. 25 with first groove 96 aligned with the projection 95 on the end piece 92 . The parts are now rotated in the direction of the arrow shown in FIG. 25 moving the projection 95 up the ramp 97 and around until it engages the second groove 99 as shown in FIG. 26 .
[0091] Prior to assembling the parts onto the end piece 92 the operating trigger lever 81 of the construction shown in FIG. 19 or FIGS. 20 to 22 is moved to the free position. With the construction shown in FIG. 19 the hand wheel 68 is rotated to a position in which there is maximum movement and the handle is then closed which produces a reduced tension force and enables the end piece 30 , which has been passed through a circular opening 121 in the backing member 90 and through the shaped opening 114 in the movable operating member 110 which acts to hold the parts in position.
[0092] In the construction shown in FIGS. 20, 21 and 22 this position is achieved by moving the operating trigger lever 81 to its first tension position.
[0093] The inserter is now assembled and ready to receive the cup 2 with which it is to be used. The shaped cup is aligned with the shaped edge 91 of the backing member 90 as shown n FIG. 27 . The cup is then placed onto the cup holder 1 as shown in FIG. 28 with the flexible element within the outer rim of the cup in a similar manner to that described with the earlier embodiments.
[0094] When used with the arrangement shown in FIGS. 17 to 19 the adjustment hand wheel is adjusted to provide maximum tension in the flexible element 3 and operating trigger level 60 is then moved to provide the maximum tension of the flexible elements 3 which thus acts to expand the flexible ring 120 by compressing it between the backing member 90 and the operating member 110 , the ring thus expanding radially to grasp the cup 2 .
[0095] It will be understood that the flexible ring 23 now performs two functions. It not only provides a resilient bias to hold the parts in position when they are first located on the end piece 92 but, on further compression, it also acts to grasp the cup 2 .
[0096] A number of alternative cup holders can be provided of different dimensions for use with cups of different dimensions so that a modular construction is achieved. Thus, one handle and extension can be used with a large number of different shaped and sizes adjustable cup holders.
[0097] The various parts can be made from any convenient material, for example the various parts of the adjustable cup holder can be made from metal or a synthetic plastics material. Again, the handle and extension can be metal or a synthetic plastics material as can the end piece. It is also possible to use different materials for the other parts, for example the flexible element could be made from a suitably strong synthetic material as well as from metal.
[0098] Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | An acetabular cup shell inserter has a first end with a handle and a wire coupling element. The inserter has a shell insertion end opposite the first end having a radial expandable element for contacting an inner surface of the acetabular cup shell. A tubular portion is provided extending between the handle end and the insertion end. The tubular portion may be curved. A wire having a first end coupled to the coupling element at the first end is provided. The wire extends through the tubular portion and into the insertion end, the wire having a second end coupled to a moveable element for expanding the expandable element. The inserter includes a system for applying tension to the wire, such as by moving the wire in a direction towards the first end, the tension causing the expandable element to expand and grip the inner surface of the shell. | 0 |
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