description
stringlengths 2.98k
3.35M
| abstract
stringlengths 94
10.6k
| cpc
int64 0
8
|
|---|---|---|
CROSS REFERENCE TO RELATED APPLICATION
This application claims benefit under 35 USC section 119(e) to U.S. Provisional Application No. 62/218,632, filed on Sep. 15, 2015, entitled VEHICLE-MOUNTED SENSORLESS MOTOR WITH EDGE-CONNECTED TERMINATION, the entire disclosure of which is incorporated herein by reference.
BACKGROUND
The present invention relates to a vehicle-mounted sensorless motor apparatus with a motor termination connector for motor phases U, V, and W; and more particularly relates to a motor having a stator circuit board integral to the motor, a controller circuit board separate from the stator circuit board, and mating connectors for connecting circuits between the circuit boards for controlling the motor phases U, V, and W. The present innovation is well adapted for use in an automatic transmission fluid pump/motor apparatus, but is not believed to be limited to only that use.
Sensorless automatic transmission fluid (ATF) motors can be used to drive pumps for pumping automatic transmission fluid on a vehicle. Such motors are useful for several reasons, including their compact design, reliability, control, and cost effectiveness. Sensorless ATF motors typically have a connector-based termination on the circuit boards for phases U, V, and W, so that a controller circuit board can control circuits defined in part by the stator circuit board for operating the motor's rotor. It is important that the assembly be compact, but also easily connected (since the assembly may be a blind assembly), reliably connected (including good and consistent electrical contact and that is also mechanically resistant to pull-apart), and assembled with a minimum of components and lower cost component (for competitive reasons).
One example of prior art is shown in FIGS. 18-21 , which illustrates an ATF motor 100 connected to a pump positioned inside a transmission fluid pan for pumping pooled automotive transmission fluid as needed to vehicle components. The motor 100 includes a stator circuit board 101 with a first multi-point (female) connector 102 (sometimes called “terminal header”) soldered to the board 101 , and a controller circuit board 103 having a mating second multi-point (male) connector 104 (sometimes called a “socket header”) soldered to the board 103 , with the mating connectors 102 and 104 having mating pin and sockets for connecting different circuits between the circuit boards 101 and 103 for controlling phases U, V, and W of the motor 100 to rotate the motor's rotor. The connector 102 is soldered into the electronics in the stator circuit board 101 , and the connector 104 is soldered to the electronics of the controller circuit board 103 , which adds significant expense and is a quality concern. The male connector 104 includes multiple miniaturized parallel pins 105 adapted to fit snugly into mating sockets for electrical connection. The pins are designed to be as small as possible to meet space/size, weight, and functional requirements, since the space within the transmission fluid pan is small, but concurrently must be sufficiently large for good surface area for providing electrical connection. The connectors 102 and 104 both include metal conductors held by non-conductive material (such as plastic), with the non-conductive material being designed to assist with accurate alignment of the pins and sockets during assembly and interconnection, but also providing good retention strength after assembly. A quality problem occurs when one or more of the pins are deformed or damaged during assembly, resulting in poor (or no) electrical connection. This problem is compounded by the blind assembly, and by the small size and low bending strength of the pins. Improvement is desired to simplify the assembly, lower cost, improve assemble-ability (especially during a blind assembly), improve reliability of retention after assembly, improve integrity and reliability of the electrical connection made in the multiple circuits during assembly, doing so while maintaining low cost of components and assembly, and while also providing a design that takes up as small of space as possible by the components/assembly.
SUMMARY OF THE PRESENT INVENTION
In one aspect of the present invention, an apparatus for electrically connecting a motor's on-board stator circuit board to a controller circuit board, comprises: A) one of the stator circuit board and the controller circuit board including an edge with spaced-apart pads of electrically-conductive material for connecting to the multiple electrical circuits; and B) the other the stator circuit board and the controller circuit board including an edge connector with conductors each having at least one protruding arm positioned to both engage the pads for electrical contact and also frictionally engage the pads for mechanical retention.
In narrower aspects, the pads include first pads on one side and second pads on an opposite side that are aligned with the first pads; and the at least one protruding arm on each of the conductors includes opposing arms that define a pinch point therebetween, the pinch point being dimensioned to cause the opposing arms to each contact an associated one of the pads.
In another narrower aspect, the apparatus does not include any mechanical connecting structure creating a substantial retention force other than the retention force created by the conductors on the pads.
In another narrower aspect, the pads include duplicative pads on opposite sides of the circuit board, both connected to the electrical circuit, thus leading to a duplicative connection that is more reliable and robust.
In another aspect of the present invention, a method for electrically connecting a motor's on-board stator circuit board to a controller circuit board, comprises: A) providing on one of the stator circuit board and the controller circuit board, an edge with spaced-apart pads of electrically-conductive material for connecting to the multiple electrical circuits; B) providing on the other the stator circuit board and the controller circuit board, an edge connector with conductors each having at least one protruding arm positioned to both engage the pads; and C) assembling the edge connector onto the edge so that the conductors electrically engage the pads for electrical contact and also frictionally engage the pads for mechanical retention.
These and other aspects, objects, and features of the present invention will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIGS. 1-1A are side views, partially schematic, showing an ATF motor/pump apparatus submersed in automatic transmission fluid inside a transmission fluid pan, the motor including a stator circuit board connected to a controller circuit board, the controller circuit board including an edge-of-board electrical connector (called “edge connector”) with tuning-fork-like conductors for engaging mating conductive pads along an edge of the stator circuit board, FIGS. 1 and 1A showing the motor extending in different orientations (i.e. opposite directions).
FIG. 2 is a side view of the controller circuit board and circuit-board-attached edge connector of FIG. 1 .
FIG. 3 is a perspective view of the edge connector engaging the pads on the (circle-shaped) stator circuit board.
FIG. 4 is a cross-sectional view showing the electrical connection provided by the tuning-fork-like conductors to the pads on the stator circuit board.
FIG. 5 is an exploded view of FIG. 3 (with only the center one conductor 31 shown).
FIGS. 6-8 are views of one of the tuning-fork-like conductors, FIGS. 6-7 being side and plan views, FIG. 8 being an enlarged view of the circuit-board-attached pin on the conductor.
FIGS. 9-13 are views of the edge connector of FIG. 3 , FIG. 9 being a perspective view,
FIGS. 10-12 being orthogonal views, and FIG. 13 being a cross section showing the conductor inside the non-conductive plastic material of the edge connector.
FIG. 14 is a plan view of the stator circuit board of FIGS. 1 and 2 .
FIGS. 15-16 are enlarged views of opposing sides of the end of the controller circuit board where the edge connector engages the controller circuit board.
FIG. 17 is a schematic showing a vehicle electrical system including a controller PCB connected using tuning-fork-connectors to conductive pads on a 1st on-board static motor PCB, and including a 2 nd on-board static motor PCB connected using tuning-fork-connectors to conductive pads on the 1 st on-board static motor PCB.
FIGS. 17A-17D are layers of the stator circuit board, the layers showing redundant pads connected to circuits on the stator circuit board, the redundant pads causing redundant connection of the controller and stator circuit boards to improve sureness and robustness of the electrical connection.
FIGS. 18-19 are side views of prior art, FIG. 18 showing a stator circuit board assembled to a controller circuit board by a male terminal header connector (with circumferential shield around projecting pins) and socket header connector, FIG. 19 being an exploded view of same.
FIGS. 20 and 21 are perspective views of the socket header connector and terminal header connector shown in FIGS. 18-19 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present apparatus 20 ( FIG. 1 ) is illustrated as positioned in a transmission fluid pan 21 partially filled with transmission fluid, and includes a motor 21 with rotor 22 driving a pump 23 for pumping the automatic transmission fluid to various vehicle components. The motor 21 has a stator circuit board 25 integral to the motor and operably connected to its stator 26 , a controller circuit board 27 separate from the stator circuit board 25 , and a connector 28 on the controller circuit board 27 for electrically (and mechanically) connecting to a connecting arrangement of pads 30 on the stator circuit board 25 to connect to different circuits between the circuit boards 25 and 27 to control operation of the motor's rotor via phases U, V and W. The pads 30 on the stator circuit board 25 comprise enlarged spots of conductive material on opposing sides of the stator circuit board 25 near an edge of the circuit board 25 . For convenience, the pads 30 are referred to herein as a “connector arrangement”, since the pads 30 are arranged to provide connection and also provide frictional retention force by engaging the arms of the tuning-fork-like conductors 31 in the connector 28 . In a broadest sense, in the illustrated apparatus, it should be understood that there is no traditional connector on the controlling circuit board 27 .
The connector 28 is shown in FIGS. 1 and 4 , which shows the assembly, and is shown in FIGS. 6-8 which shows the conductors 31 , and in FIGS. 10-13 which show the connector 28 with conductors 31 . The connector 28 includes a molded non-conductive body (of plastic) holding multiple tuning-fork-like conductors 31 (three shown) in parallel positions each defining an entrance “jaw” corresponding to the pads 30 . This arrangement allows for elimination of the socket header used in the prior art connector 101 described above and shown in FIGS. 18-21 , which is a tremendous cost savings in material, assembly cost, and savings in space consumption. The conductors 31 have conductive arms 31 A that extend in a parallel direction, with the angled inner surfaces of the arms forming a funnel-shaped entrance 31 B (which facilitates blind assembly onto the edge of the stator circuit board 25 ), inwardly protruding bumps 31 C (which create a pinch point promoting good electrical connection to the pads 30 and also positive frictional retention forces on the pads 30 on opposing sides of the stator circuit board 25 ), and a spaced inner portion 31 D (for receiving the edge of the stator circuit board 25 . It is noted that the quality and surety of the electrical connection is greatly increased due to the electrical contact with pads 30 on opposite sides of the stator circuit board 25 .
FIG. 1 shows a particular arrangement where the motor's stator and rotor are shown extending away from the controller circuit board. However, this is done for convenience and illustrative clarity, but it is contemplated that the motor's stator and rotor can extend in any direction relative to each other.
Skilled artisans will understand that a variety of different materials and constructions are possible while staying within a scope of the present innovative concepts. The illustrated stator board 25 is a laminate type, the conductors 31 are a conductive metal having a Young's modulus of 131 GPa, and the terminal housing (plastic body of the connector 29 ) is a material having a Young's modulus of 10 GPa. The install force for assembly and retention forces for the assembly can be varied in a number of ways, such as for example by changing materials, treating the contacting surfaces with surface treatment (e.g. plating or coatings), and/or changing a shape of the conductor arms 31 A (i.e. changing the angle of the funnel entrance and/or of a dimension and shape of the pinch point and/or flexibility/resiliency of the arms). The illustrated prototype successfully passed several tests, including tests of lower install/higher retention forces, electrical integrity/ampacity, thermal shock, powered vibration with heat, and powered thermal cycle. It is noted that the present illustrated connection has operated effectively while communicating 20 amps or more.
The present arrangement is particularly useful in sensorless ATF (automatic transmission fluid) motors used to drive pumps for pumping automatic transmission fluid, because it provides a very compact design (needed for the small space requirements in a vehicle transmission pan), while maintaining or improving reliability and cost effectiveness (needed for the high quality standards required in modern vehicles). The present assembly provides for robust, positive, and relatively easy connection (even in a blind assembly), provides excellent reliability upon connection (including excellent duplicative electrical contact and also mechanical resistance to pull-apart), while using a minimum of number of components (due in part to eliminating one of the connectors used in traditional mating-pin-and-socket electrical connectors) and while also using low cost components and low cost assembly techniques/processes. It is contemplated that the above innovative aspects can include a device connected to and driven by the motor(s), such as any fluid pump or air pump device, a power steering device, an AC compressor, a motor-powered power brake, and substantially any motor-powered component or accessory used in a vehicle or in a larger assembly.
FIG. 17 is a schematic showing an alternative circuit comprising a vehicle electrical system including a controller PCB 27 connected using tuning-fork-connectors 28 with arm-like conductors 31 engaging conductive pads 30 on a 1st on-board static motor PCB 25 , and including a 2 nd on-board static motor PCB 25 ′ connected using tuning-fork-connectors 28 ′ with conductors 31 ′ engaging conductive pads 30 ′ on an edge 25 ′ of the 1 st on-board static motor PCB 25 . It is contemplated that variations are within a scope of the present invention. For example, both on-board static motor PCB's could be connected directly to the controller PCB, with both tuning-fork-connectors being on the controller PCB and with the conductive pads along the1 st and 2 nd on-board static motor PCBs. Also, the tuning-fork-connectors could be on the static motor PCB's, and the conductive pads along the edge of the controller PCB. It is contemplated that additional tuning-fork-connectors could be used to connect PCB's while minimizing or eliminating pre-assembled/pre-manufactured electrical connector components.
FIGS. 17A-17D show adjacent layers of the stator circuit board 25 , where the layers include redundant pads (identified as items C, U, V, W) connected to circuits on the stator circuit board, the redundant pads causing redundant connection of the controller and stator circuit boards to improve sureness and robustness of the electrical connection.
It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.
|
An apparatus electrically connects a motor's on-board stator circuit board to multiple circuits on a controller circuit board using an edge connector on the controller circuit board that engages opposing pads on an edge of the stator circuit board. The edge connector includes tuning-fork-like conductors each with pairs of protruding arms positioned to both engage the pads for electrical contact and also frictionally engage the pads for mechanical retention. A related method of assembly uses the edge-connect system for quick, reliable and sure assembly even under blind assembly conditions.
| 7
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-and-part of U.S. Ser. No. 12,966,195 granted U.S. Pat. No. 8,511,404 which claims priority from U.S. Ser. No. 12,966,195 based on WO 156552A1 PCT 2009 and GB0811815.0 (27.06.2008) granted GB 2460096.
[0002] This application is a continuation-and-part of copending U.S. patent application Ser. No. 12,966,195 filed Dec. 13, 2010, and entitled “DRILLING TOOL, APPARATUS AND METHOD FOR UNDERREAMING AND SIMULTANEOUSLY MONITORING AND CONTROLLING WELLBORE DIAMETER”, which is a continuation-and-part of International Application number PCT/ES09/70261, filed Jun. 27, 2009 and entitled “DRILLING TOOL AND METHOD FOR WIDENING AND SIMULTANEOUSLY MONITORING THE DIAMETER OF WELLS AND THE PROPERTIES OF THE FLUID”, and claims priority to and the benefit of GB 0811815.0, filed Jun. 27, 2008 and entitled “Expansion and Calliper Tool”, the entireties of which applications are hereby incorporated by reference as if fully set forth herein.
FIELD OF THE INVENTION
[0003] This invention relates to a dynamic sensing underreamer capable of detecting reamer diameters or positions and the terms reamer or underreamer are used to designate an expandable tool. In one embodiment this invention relates to a tool, apparatus and method capable of enlarging and dynamically sensing positions or diameters of expandable tools, especially, expandable reamers for use in wellbores in the oil and gas industry. The expandable blocks of the tool can be configured with cutting or stabilising elements locatable in a plurality of known positions that form a variable gauge expansion tool. Dynamic position sensing means provide data on the reamer status or diameter and position sensing may be via analogue or digital means.
[0004] Alternatively or additionally further embodiments of the invention allow for acoustic sensors or mechanical gauge probes to measure the underreamed wellbore diameter. Further measurements where required can be obtained such as formation properties, vibration, rpm, rotation, flow, hydraulic force, pressure, torque, temperature.
[0005] Additionally or alternatively pressure or flow indicators based on the location of the block or the location of a detector may also be used to sense or indicate or infer or signal the position of the blocks. Variations in sensors or signals may be electrical, mechanical or a combination of both. It is not essential that physical sensors measure the distance in such an embodiment because the radially extended positions or underreamer diameters may be sensed by indicative means. Such types of embodiments may be considered modular as they can be configured in separate modules or housings yet sharing common features.
[0006] It is to be understood that the term ‘expansion’ as used herein refers to the capacity of the tool to expand outwardly and against the interior wall of a passage, such as a borehole, especially a wellbore, or a tubular used as a casing, and then to apply pressure or a cutting action against the wall. It is not always essential that the wall itself be expanded, since the tool can be used for centralisation or stabilisation or like purposes without necessarily expanding the passage.
[0007] When constructing an exploration or production well, numerous downhole operations are conducted to drill and measure the borehole so that it meets the desired dimensions specified in the well-plan.
[0008] An underreamer (which covers all manner of reamers, expandable reamers, extendable reamers and the like) is used to enlarge the diameter of the borehole beyond its original drilled size. Enlargement (underreaming or reaming using expandable/extendable tools) is typically done below a restriction in the borehole, and the cutting diameter of an underreamer is always greater than that of the pass-through diameter of the restriction. Additionally, an underreamer is provided with activation and deactivation modes and mechanisms for extending and retracting cutting elements to ensure effective underreaming once it has passed below the restriction.
[0009] The time-lag associated with the separated operations of underreaming and measurement leads to uncertainty and unnecessary cost.
BACKGROUND OF THE INVENTION
[0010] Oil and gas accumulations are found at depth in different geological basins worldwide. Exploration and production of such accumulations rely on the construction of a well according to a well plan.
[0011] Various well types exist and are defined according to usage such as wildcats or those used in exploration, delineation, and production and injection. Variations in well profile exist also according to vertical, slant, directional and horizontal trajectories. Each well differs according to the oil company's objectives and the challenges that a given basin presents from the surface of the earth or the ocean to reaching the hydrocarbon reservoir at a given underground depth.
[0012] Engineering challenges are related to the location of the well-site such as onshore or offshore, seawater depths, formation pressures and temperature gradients, formation stresses and movements and reservoir types such as carbonate or sandstone. To overcome these challenges, a highly detailed well plan is developed which contains the well objective, coordinates, legal, geological, technical and well engineering data and calculations.
[0013] The data is used to plot the well profile, and plan its execution using precise bearings, which is designed in consecutive telescopic sections—surface, intermediate and reservoir. To deliver the well objective and maintain the integrity and operating capacity of the well over its lifecycle, a given wellbore with multiple sections and diameters is drilled from surface. Although there are many variants, a simple vertical well design could include the following dimensions: a surface or top-hole diameter of 17½″ (445 mm), intermediate sections of 13⅝″ (360 mm) and 9⅝″ (245 mm) narrowing down to a bottom-hole diameter of 8½″ (216 mm) in the reservoir section.
[0014] Each consecutive section is ‘cased’ with a number of metal tubes placed into the wellbore with the specified diameter according to the length of the section. Casing tubes are connected to each other after which they are cemented into the outer wall of the well. In this way, a well is constructed in staged sections, each section dependent on the completion of the previous section until the well is isolated from the formation in question along the entire distance from surface to the reservoir.
[0015] Scarcity of oil and gas is driving oil and gas companies to explore and develop reserves in more challenging basins such as those in water-depths exceeding 6,000 ft ( 1800 m ) or below massive salt sections. These wells have highly complex directional trajectories with casing designs including 6 or more well sections. Known in the art as ‘designer’ or ‘close tolerance casing’ wells, these wells have narrow casing diameters with tight tolerances and have created a need to enlarge the wellbore to avoid very narrow reservoir sections and low production rates.
[0016] Therefore, the bottom-hole assemblies that are needed to drill these wells routinely include devices to underream the well-bore below a given casing diameter or other restriction. In this way, underreaming has become an integral part of well construction and there is now an increased dependence on underreaming to meet planned wellbore diameters.
SUMMARY OF THE INVENTION
[0017] The present invention has for a principal object to provide an improvement on the prior art in wellbore underreaming and wellbore measurement wherein the actual position of the underreamer is sensed or indicated.
[0018] Measurement may involve the acquisition and communication to surface of various types of wellbore data such as azimuth, inclination and borehole diameter or rugosity, formation types, dips or bedding angles.
[0019] The present invention seeks to provide certainty of operation of underreaming and eliminates the need for separate corrective underreaming runs by providing real-time data which allows the driller to respond earlier thereby saving time and money on wellbore operations.
[0020] It is thus an object of the present invention to provide reaming expansion blocks integrated with position sensing which can be used to assess the functioning and diameter of the wellbore-widening operation and, if the position and diameter is found insufficient or undergauge, to automatically detect and diagnose the potential faults, and to repeat underreaming until a satisfactory result is achieved. It is a further embodiment of the invention that provides the measurement of wellbore diameter as well as other measurements such as formation characteristics.
[0021] Although underreaming is the principal route to wellbore diameter enlargement, the invention may be applied to enlargement means integrated with bicentre bits, fixed wing bits, eccentric underreamers and expandable bits.
[0022] The tool is principally enabled to detect reamer positions or reamer diameters. In a separate and further embodiment the tool can conduct diagnostics according to a logic circuit. In this way, the user can achieve a planned or desired underreamer activation or deactivation and at any given time check that the underreamer is functioning correctly. This reduces downtime and uncertainty.
[0023] In such an embodiment of the invention the tool may be linked to a micro-processor. Additionally or alternatively the tool may be further linked to a MWD/LWD. Such types of embodiments may be considered modular as they can be configured in separate modules or housings yet sharing common features.
[0024] In this way, different types of modular solutions may be provided according to the need of the wellbore underreaming operation. For example, an underreamer with positional sensing only, an underreamer with positional sensing and other measurements such as calliper or vibration or underreamer with calliper only. These solutions can be configured to provide increasing levels of problem solving according to the application. For example if a problem occurs and if the corrective steps have been taken and the underreamer position sensing indicates an undergauge position then this may solve the problem in certain applications such as swelling shales or radial shrinkage. For other applications, such as requiring tight tolerances, a further caliper measurement may indicate that the desired hole diameter is still not being delivered a signal may be sent to the rig-surface or to the location of the operating engineer so that further remedial action can be taken, according to a logic circuit. This may include extending cutter blocks in response to caliper data, checking block positions or any number of logic steps. A memory card may store sensor information that can be downloaded at surface when the tool is retrieved, or sent to the surface by telemetry. In this way, the invention is entirely flexible and configured according to the application.
[0025] The invention can be configured with a modular processor which can be linked to a MWD pulser and capable of receiving data such as azimuth, inclination and borehole diameter or rugosity, formation dips or bedding angles.
[0026] The tool may also have a built-in link to a mud-pulse telemetry system to allow real-time monitoring of the under-reaming operation (cutter-block position, caliper measurements, fluid properties, pressure, rotation, torque, etc).
[0027] In the underreamer and positional sensor module there may or may not be a keyway to provide a channel for wiring to and from the sensors to a processor and MWD when such components are configured. The wiring can be used to transmit other data retrieved by other sensors, as well as positional data from the mechanical blocks, to the processor. The processor can process this data and sends it to the transponder to be sent to the control system at the surface. The keyway may be sealed and filled with a means to absorb vibration such as silicone gel or grease and to maintain wires in position.
[0028] In the embodiment of the underreamer with positional sensors the tool itself may communicate to surface by wired or wireless means. Additionally or alternatively the processor can transmit data to the surface by means of a mud-pulser which uses a series of binary codes at a given frequency using drilling fluid as means of transmission. Other means of wireless transmission can be used, using radio frequency or electro-magnetic pulses. This allows up and downlink of the tool in order to receive and transmit data and commands. The data may be transmitted to the surface for use by the drilling operator or may be further transmitted by satellite to a remote operations centre.
[0029] One embodiment of the invention provides for a wellbore underreaming tool or apparatus, which is particularly applicable in oil and natural gas wells, arranged for attachment to a rotary drill-bit and associated drill-pipe, which comprises at least one radially extendable cutter block ( 62 ), at least one positional sensor ( 76 or 64 - 66 ) to determine the wellbore diameter, to verify and control a desired underreamer diameter ( 22 ).
[0030] The positional sensor may be dynamic and the tool support may be the drill string but it may also be a length of coiled tubing.
[0031] The tool body is a cylindrical high grade steel housing adapted to form part of the bottom-hole assembly by means of a screw connection arranged at the end of the tool, which is coupled to the drill bit. The attachment need not be direct, but may be indirect, depending on the requirements of the different elements of each drill string and each well. The lower end of the BHA may be a drill bit, or a bull nose and/or an expandable bit and various components between the tool there may or may not be a means for directional control of the wellbore such as a rotary steerable system.
[0032] In one embodiment of the invention, the expansion operation is an underreaming application, and expansion elements comprise a set of cutter blocks optimally configured with cutter inserts and nozzles. In another embodiment, the expansion elements may comprise expansion blocks, which may be of similar construction to the cutter blocks, but having outer surfaces where cutter elements may be replaced by a hardened material. Such expansion blocks may simply bear under pressure against the inside of a tubular wall, with sufficient force to deform it outwardly to a larger diameter. In yet another embodiment, the same blocks may simply bear against the underreamed wellbore in order to stabilize the tool within the wellbore without enlarging the bore. The same blocks maybe received within an additional section of the tool or a separate steel body suitably prepared to provide a means of stabilization to the expansion operation. In a further embodiment, the same blocks maybe received within an additional section of the tool or a separate steel body suitably prepared as apparatus to provide a means of stabilization for underreaming applications.
[0033] In one embodiment where the wellbore expansion activity is underreaming the cutter blocks are situated within the tool body in an open chamber, the outer surface of which is composed of a plurality of high strength cutter elements such as polydiamondcrystalline inserts arranged externally. The cutter block is provided with a flow of drilling fluid via an external nozzle adjacent to the set of cutters which allows drilling fluid to flow from an internal bore connected to a source of said drilling fluid.
[0034] In another embodiment, the tool comprises a module that can be coupled by means of a thread connection to the body of the tool which comprises expandable stabilizing blocks in order to stabilize the tool against the wellbore walls during underreaming and measurement and if so required, increase or expand the diameter of the metallic tube casing of the well.
[0035] It is to be noted that the description herein of the expansion blocks is applicable generally, irrespective of the function of cutting, expansion or stabilization of the drill string. Thus, the cutter blocks are provided with cutting inserts or teeth to enable underreaming of the wellbore that may be replaced by hardened smooth surfaces for expansion operations of an expandable steel tubular inside the wellbore.
[0036] In yet another embodiment the microprocessor control means ( 68 ) are adapted to receive, during drilling operations, information from the positional sensors of the extendable cutter block in order to control the extension and retraction of said block in order to detect and correct failures in real-time and achieve the desired wellbore diameter.
[0037] The tool normally comprises a plurality of such cutter blocks, arranged symmetrically around the tool. Two cutter blocks would be on opposite sides of the tool, three blocks would be separated by 120 degrees, four blocks by ninety degrees, and six by sixty degrees. Or the blocks may simply be housed in separate housings allowing for a plurality of cutter blocks. In operation, the tool is typically rotated together with the drill string as well as being moved axially along the wellbore.
[0038] The tool body is provided with an internal bore for receiving drilling fluid via a device nozzle adjacent the cutter. In each case, the nozzles provide a fluid flow that help to keep the cutters clean and prevent the build-up of clogging debris from the underreaming operation and provide a cooling and lubricating function for the cutters. In one embodiment of the present invention the tool incorporates a non-mechanical means of reamer position measurement or reamer diameters such as a pressure measurement. Suitable means for pressure measurements are pulse heads or flow restrictors such as castellations, turbines or valve plates which can reciprocate or rotate or vibrate to create a dynamic pressure signal or a plurality of pressure signals. The pulse head or flow restrictor may be connected to a mandrel or travelling lock or sleeve thereby the displacement related to the movement of the extendable blocks outward. Other restrictors may be graduated and allow for reduced turbulent flow with less chance of erosion. In either case treatments such as tungsten carbide, HVOF etc may be applied.
[0039] In yet another embodiment a bending moment sensor may detect bending moments on the tool allowing for activation forces to be optimized by increasing or decreasing activation forces. The bending moment sensor may show that further activation force is required or lower force or that parameters should be changed such as the angle, rop, WOB, FLOW, directional control system blades. Optimal configurations of the invention are envisaged based on application needs.
[0040] A pulse head may travel through a number of rings and thus create a number of pulses related to position. For example, 1 pulse may be deactivated, 2 pulses 1 inch extended, 3 pulses 2 inches extended and so on. Additionally or alternatively the reverse is also possible as is a further embodiment wherein the duration of the pulse may indicate positional data. For example, a long pulse indicates activation while a short pulse is deactivated or the alternate is possible. Further pulse encoding may be planned dependent on the type of frequency and duration and other pulsers that may be in the hole as is the case when directional or LWD/MWD companies are providing such measurements.
[0041] The positional sensing means are generally located in the tool or cutter block or mandrel in a chamber but in an alternative configuration of the tool may be placed within the cutter block itself in the most radially extended zone among the cutting elements or linked to a nozzle opening to the wellbore. Other embodiments are for example, a pressure sensor may detect chamber pressure. Additionally or alternatively the sensing means may be located below a sealed area or within a seal area.
[0042] In one embodiment, the invention provides for a method of operating an expansion tool or apparatus to underream a borehole to a desired dimension below a restriction, which comprises locating said tool or apparatus in said borehole on drill-pipe below a restriction, extending a set of cutter blocks to an expansion diameter greater than the restriction, rotating the tool and moving it axially along the borehole on the drill string or other support, sensing the block position by detection means and continuing underreaming until the desired dimension is achieved.
[0043] In accordance with yet another method of the invention, the tool may be provided with expandable cutter control means responsive to dimension data received from positional sensors or caliper means. In this way, an integrated tool and apparatus which is capable of diagnosing under-performance and correcting it may be realized. The dimension data may prompt for tests and checks on the effective deployment of the expandable blocks, may trigger a repeated cycle of expansion, or activate a further set of cutters and may provide data to a surface monitor to signal an opportunity for operator intervention.
[0044] The processor uses this data to correlate whether the pre-programmed wellbore diameter is actually being underreamed via block position sensing. Where the processor detects a fault or difference between the two minimum measurements it automatically troubleshoots the fault using a logical procedure.
[0045] The skilled operator will readily appreciate that other procedures may be implemented by the logic circuit or control program within the tool's processors, which can be programmed to cover other scenarios.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] The various embodiments of the invention are illustrated by way of non-limiting examples in the accompanying drawings, in which:
[0047] FIG. 1 is a general diagrammatic view of an oil or gas well showing surface structures and the interior of the underground wellbore, with a tool in accordance with the invention as part of the final bottomhole assembly;
[0048] FIG. 2 is a longitudinal section of the tool and apparatus according to one embodiment showing the expansion elements constituted by cutter blocks; FIGS. 2 a and 2 b show the tool of FIG. 2 activated and deactivated respectively and further configured with a calliper and mud pulser.
[0049] FIG. 2A and FIG. 2B respectively show configuration with calliper ( 58 ) and cutters ( 62 ) activated and deactivated.
[0050] FIG. 3 is a cross section of the tool as seen from the drill bit, showing the diameters of the drill bit, of the pass-through casing and of the desired underreaming of the wellbore in accordance with the invention shown in the previous Figures, in the operative mode of the expanded expansion cutter blocks (activated operating mode);
[0051] FIG. 4 shows a cross-section of the tool as seen from the drill bit, showing the diameters of the drill bit, of the casing and of the desired underreaming of the wellbore, according to the invention shown in earlier figures in the operative mode of the retracted expansion cutter blocks (deactivated operating mode);
[0052] FIG. 5 is a general view of the well illustrating telemetry of the underreaming and drilling data recorded by the tool or apparatus;
[0053] FIG. 6 corresponds to FIG. 5 but illustrates downlink telemetry of the data with parameters sent in order to control the underreaming and drilling by the tool or apparatus; and
[0054] FIG. 7 shows an embodiment of an expansion block configured with cutters;
[0055] FIG. 8 is a view corresponding to FIG. 7 showing an alternative construction with external nozzle;
[0056] FIG. 9 is a longitudinal section of one embodiment of the tool or apparatus showing the expansion elements constituted by a set of cutter blocks and a further set of cutter blocks in a deactivated state. Equally the first or second set may be replaceable with an expandable bit.
[0057] FIG. 10 is longitudinal section of an expandable stabilizer with a dynamic positional detector means contained therein and with cutter blocks in a further module.
[0058] FIG. 11 shows a longitudinal section showing two locations for positional detector means above and below a mud pulser
[0059] FIGS. 12 and 13 show a detail of a dynamic position detector with and without a pulse head of one embodiment of the tool or apparatus showing the expansion elements constituted by a set of cutter blocks and a further expandable bit replacing the second set of cutter blocks.
[0060] FIGS. 14 and 15 detail a preferred embodiment with two locations for dynamic position detection contained within and partly without respectively of expandable cutter assembly.
[0061] FIGS. 16 , 17 show different configurations of a dynamic pulse head for position detection with a spring and compression/expansion chamber.
[0062] FIG. 18 shows where the pulse head is connected to a mandrel which moves up or down the housing.
[0063] FIG. 19 shows an embodiment wherein the blocks are connected to a single chamber
[0064] FIG. 20 shows an embodiment where the dynamic position detector is placed in a fluid pathway to the annular.
[0065] FIG. 21 shows yet another embodiment leading drilling fluid from a through passage ( 90 ) to an oscillating pulser.
DETAILED DESCRIPTION OF THE INVENTION
[0066] As shown in FIG. 1 , an exploration or production rig comprises a surface structure ( 10 ) at the wellhead, a wellbore ( 20 ), a drill string ( 30 ) in the wellbore and a bottom-hole assembly ( 40 ) at its lower end where the tool or apparatus ( 50 ) may be configured according to the present invention.
[0067] The tool or apparatus ( 50 ) comprises at least one underreamer module integrated with a sensing means for reamer position detection or reamer diameter signal, and capable of connection to a drill-bit.
[0068] Further embodiments can be configured as desired adding or removing modules: module housing the expandable cutter blocks and positional sensors, module housing the positional sensors, callipers, sensors and processors and the module with expandable stabilizer blocks or expandable blocks to expand a tubular within the wellbore.
[0069] The signal or position is detected according to the position so that for a 12¼″-14¾″ tool it could be configurable and extended to a plurality of radial positions between 12¼″ and 14¾″. Generally such reamer positions are dependent on the pass through ID of casing and are expressed as increase in diameter relative to the bit size or reamer body size. Accordingly such expressions are generally in the order of 1″, 1.25″, 1.375″, 1.5″, 1.875″, 2.5″, 2.75″, 3″, 3.5″, 3.875″ and 4″ and so on. Other sizes are in the order of 0.5″, 0.75″ and so on.
[0070] Alternatively or additionally the reamer body size or pass through dimension can be used to denote the expandable ratio or configured expandable reamer positions. Generally denoted in a such a manner these would be expressed in the order of 12.25″-14.75″, 14.75″-17″, 16.5″-19.5″, 18.125″-21″, 18.125″×22″, 16.5″×20″, 14.5″×16.5″, 12.25″×14.75″, 10.625″×12.25″, 8.5″-9.875″, 9.25″ to 10″, 11.25″ to 12.25″, and so on.
[0071] The longitudinal section of the tool illustrated in FIG. 2 comprises a steel tool body with connection ( 82 ) provided with an internal flowbore and if required a wellbore diameter measurement caliper ( 76 or 64 - 66 ) with the cutter blocks ( 62 ). The expandable cutter ( 60 ) is composed of various cutter blocks ( 62 ) placed symmetrically and radially outwards of the tool body ( 52 ) as shown in FIG. 2 in the activated status with the blocks extended outside the tool.
[0072] In one embodiment the tool may incorporate an acoustic caliper comprising an acoustic transmitter and receiver which can be housed within the body of the tool in sealed recesses ( 64 and 66 or 76 ). Tool performance is verified using the micro-processor ( 68 ) that compares data recorded by the acoustic receiver ( 66 or 76 ) with the programmed wellbore diameter, thus detecting possible undergauge hole diameters. The tool is automated according to logic control sequences stored in each processor ( 68 ) to deliver a desired wellbore diameter and in order to ensure the underreamer is functioning correctly. Once verification and corrective steps have been taken, and if the caliper for measuring the underreamed wellbore diameter ( 66 or 76 ) indicates that the required hole diameter is still not being delivered, a signal is sent via the mud-pulser ( 56 ) to the rig-surface ( 10 ) to allow control commands to be sent by the operator either locally or by remote control. These control commands adopt the relevant operative and corrective measures such as modification of the pump flow rate of mud or drilling fluid, activation of cutter blocks in response to caliper data, replacement of the bottom-hole assembly etc. The memory card associated with the processor ( 68 ) stores data from the calipers, fluid properties measurement sensors. The said data is transmitted in real time in order to be used in the underreaming and drilling operations ( 56 ) or physically downloaded by removing said card when the tool is retrieved from the well.
[0073] FIGS. 2 a and 2 b activated and deactivated respectively show how the tool is provided with a built-in link to the telemetry system ( 56 ) which also serves to monitor performance of the under-reaming operation, position of expansion blocks ( 62 ) and data recorded by the caliper for measuring the underreamed wellbore diameter ( 66 or 76 ). One or more acoustic sensors ( 64 or 76 ) are placed within the tool body ( 52 ) in order to emit a number of sound waves during a given time period which are reflected back by the wellbore wall and picked up by the receiver sensors ( 66 or 76 ). In a further embodiment the processor ( 68 ) calculates the distance using transit time and calibrates transit time with data from further fluid properties sensors to establish the speed of return of the acoustic waves and wellbore diameter. The processor compares the measured wellbore diameter to the programmed desired diameter. If the two measurements match given user-defined tolerances the tool continues to operate to the total depth of the wellbore section to be underreamed. Where the measurements do not match the processor automatically activates a series of logic steps to troubleshoot the fault.
[0074] As further shown in FIG. 2 , a keyway ( 78 ) provides a channel for wiring of the acoustic pulsers or transmitters ( 64 or 76 ) and the acoustic sensor/receivers ( 66 or 76 ) to the processor ( 68 ), and also to the transponder ( 72 ). The wiring can be used to transmit as much or as little data required by the configuration of the tool. For example, this may include acoustic data retrieved by wellbore calipers and fluid properties sensors as well as positional data from the cutter and stabilizer blocks to the processors and transponders. The keyway may be sealed and filled with a means to absorb vibration such as silicone gel.
[0075] FIG. 2 shows a processor ( 68 ) which provides data for transmission to surface ( 10 ) via the mud-pulser ( 56 ) FIGS. 2 a and 2 b which transmits the data to surface using a series of binary codes at a given frequency using the drilling mud itself as means of transmission. Other means of wireless data transfer may be used such as systems using radio frequency or electro-magnetic pulses.
[0076] FIG. 2 also shows an alternative location for the caliper for measuring the underreamed diameter which may be a caliper ( 76 ) arranged in an encapsulated recess connected to wiring in keyway ( 74 ) connected to the processor which may also be connected to the acoustic (transmitter/receiver) calipers ( 66 - 64 ) and a new keyway connection ( 78 ) which may be connected to an alternate processor ( 68 ) for the expandable block ( 62 or 63 ). FIG. 1 also shows an internal flow bore or axial through passage ( 90 ) in the tool to allow mud to flow through the whole bottom-hole assembly ( 40 ). The encapsulated recesses ( 64 , 66 and 76 ) may also be used to house other types of sensors such as a vibration sensor to detect stick-slip conditions.
[0077] FIG. 3 shows an uphole front view of the bit illustrating the generally designated expandable cutters ( 60 ) in the activated mode, i.e. with cutter blocks ( 62 ) expanded outwardly of the tool body and supported against the underreamed wellbore wall ( 22 ) which arises from the wellbore ( 20 ) which has not been underreamed. FIG. 3 shows the arrangement of the drill bit teeth in which there are ten curved rows of cutters ( 44 ), with cutter teeth in each one. A central drilling fluid outlet ( 46 ) indicates where drilling fluid passes through the internal flowbore ( 90 ) in the tool body ( 52 ). The direction of rotation of the bottom-hole assembly and of the drill bit is shown ( 124 ).
[0078] FIG. 4 illustrates the same front view as FIG. 3 with the expandable cutters ( 60 ) in a deactivated condition, i.e. with cutter blocks ( 62 ) retracted within the inner chambers of the tool body without exceeding the wellbore diameter that has not been underreamed ( 20 ).
[0079] In a further embodiment of the invention, each expandable block is provided with lines, strips, contacts or sensors to detect the actual position of the blocks. The signal is measured according to the position so that for a 12¾″-14¾″ tool it could be extended to a plurality of radial positions between 12¾″ and 14¾″. Each radial position is capable of being determined and sensed. In this way, it can be seen whether the block has actually been extended and determine its extension length and position. This block positional data is sent to the processor where it is stored, compared and correlated with the caliper data or data from vibration, rpm, pressure, hydraulic force, torque, flow sensors to deliver a desired wellbore diameter and also troubleshoot causes of failures. It is not necessary for the block positional sensor to be on the block. In an alternate embodiment the sensor may be on the housing. In yet a further embodiment the sensor may be on another tool or may be at surface applicable as the purpose is to establish the relative position of the block to the tool. Additionally or alternatively, pressure or flow may be used to lock the radial position and equally pressure or flow signals may be used to sense or indicate the block position. Additionally or alternatively it is not always necessary that a sensor physically measures each radial position as the groove location serves the same purpose.
[0080] As noted above, the invention provides a method of real-time drilling operation and control, which uses an extendable tool to underream the borehole to the desired dimension passing through a restriction, activating the tool, extending the extendable cutter block to a diameter greater than that of the restriction, and locating the extendable block in a predetermined position, rotating the tool and moving it axially along the borehole, enabling the simultaneous measurement and calibration of the borehole diameter by the caliper for measuring the underreamed wellbore diameter. Microprocessors connected to a control area act in response to data received from the caliper for measuring the underreamed wellbore diameter, the fluid properties or the parameters such as pressure, torque, flow with the objective of achieving the desired wellbore diameter and eliminate causes of errors or failures and minimizing drilling time by not tripping in with another caliper or performing further underreaming corrective runs.
[0081] FIGS. 5 and 6 illustrate how the underreaming tool may utilize means for communicating data from the tool such as dynamic positions, calliper for measuring the underreamed wellbore diameter, the calibration fluid properties sensors, the block positional sensors or the vibration sensors and control signals between the tool and a surface interface which may, among other functions, control the advance and trajectory of drilling during the underreaming operation.
[0082] As shown in FIGS. 5 and 6 , the wellhead surface structure ( 10 ) includes a control and communications system ( 12 ) having an interface for telemetry with downhole instrumentation including a data processor or data logger ( 14 ) and a controller ( 15 ) which decodes binary codes from the mud pulser and may be linked directly to the user's drilling terminal ( 16 ). The decoded data may be yet further transmitted by satellite ( 17 ) beyond the wellhead to a remote operations centre ( 18 ) where another user of the drilling software may access the data and the control by means of a telecommunication link ( 19 ).
[0083] The tool may be provided with a mud pulser as a standalone tool or the mud pulser and associated measurements may be provided by a third party as would be the case when a measurement while drilling or logging while drilling suite of tools is located in the BHA. The hard wiring and processor may be configured to make use of these measurements or they be sent to surface where a user may make further use of them.
[0084] The apparatus may be directly or indirectly connected to other components in the drilling or bottom hole assembly.
[0085] FIGS. 7 and 8 show variations in block and according to these embodiments of the invention, each block is provided with lines, strips, contacts or sensors that permit the processor to detect the actual position of the blocks. The signals can be configured so that they are strongest when the block is fully extended or strongest when the block is fully retracted or a signal may simply correspond to a radial position. In this way, it can be seen whether the block has actually been extended and determine its extension length and position. This data is sent to the processor where it is stored and processed.
[0086] Additionally or alternatively to digital or electronic sensing the positional signal may be generated via analogue mechanisms. Therefore, sensing means can be any suitable type of sensor or detector or indicator such as contacts, electrical sensors, strips, resistive wipers, rheostats, circuit breakers, proximity sensors, distance sensors, volumetric sensors, volumetric measurements, valves, induction loops, spirals, coils, wireless and wired. Others maybe grooves, lines, piston valves, channels, strips, mechanical, pressure or force related. Further a combination of both mechanical and electrical sensing mechanisms can be used to detect the position of the block.
[0087] The sensing means may also serve a number of functions so a strip may also form part of a seal or serve as a seal so isolating the block or housing from pressure. Or a pressure sensor may be used to detect the position of the cutter block. Further the signal may be defined as a direct or inferred or indicative position. The signal or a lack of a signal may also be provided to show a status such as a series of pressure signals according to a series of variable cutter positions.
[0088] The positional data plus the vibration data provides novel data which determines vibration as per the underreamer status i.e. activated/deactivated or in an intermediate or variable gauge position.
[0089] The underreamer status is generally performed by a position sensing means which can be a position sensor. Additionally or alternatively such sensors can be on the block or housing ( 96 , 94 ) to determine the actual position of blocks ( 63 , 62 ) and send corresponding signals back to the surface or processor ( 68 ). Suitable sensor means include any type of known of sensor or detector for position, respectively on the cutter block and housing or alternately on solely located on the cutter block or the housing itself. Additionally or alternatively the block sensing means may be on another tool or located at surface. Additionally or alternatively pressure or flow indicators based on the location of the block in the predetermined groove or location may also be used to sense or detect or indicate or infer the position of the blocks. Variations in sensors or signals may be electrical, mechanical or a combination of both. It is not essential that physical sensors measure the distance in this embodiment because the radial positions may be pre-determined by grooves and unlike the prior art which is only extended or retracted in the present invention there may be a plurality of known positions according to grooves. The term groove is used broadly and generally but serves to describe a locatable position for the cutter block. Other terms may be channels, positions, locators etc. The importance of the locatable position is to provide a variable gauge underreamer capable of being positioned in at least three positions such as open, closed and intermediate. Additionally or alternatively a further embodiment would be activated or extended, retracted or deactivated and an intermediate position in between the former two.
[0090] In another embodiment the block position sensing is not performed on the block or housing but can be performed on another tool or performed at surface.
[0091] As shown in FIG. 9 the illustrated example is of an embodiment of the tool sharing common features which is at least two sets of expandable blocks and an underreamer that uses a microprocessor ( 68 ) and electronic means to determine and control block position.
[0092] In one embodiment the position sensing function is performed by a sensor on the block or housing. The position of the underreamer is designated by sensing means in a general and broad way and can clearly use any type of position detectors, position indicators, position signals, position measurements. Such position sensing means can be analogue or digital, inferred, observed, or direct with the importance being a comparative data set relating to the underreamer status. Therefore, it is not essential that the position sensing means is contained within the underreamer as it may be contained within other downhole tools and additionally or alternatively at the surface.
[0093] The tool or apparatus may be configured with any number of modules integrated by means of screw connections ( 65 ) and ( 82 ). The body of all parts of the tool or apparatus ( 52 ) is a cylindrical high grade steel housing adapted to form part of the bottom-hole assembly (BHA) ( 40 ) via internal screw connections to ensure the through flow of drilling fluid ( 90 ). The connection may be direct or indirect depending on the needs of the different drilling components of each BHA and each well. At the leading downhole end of the BHA there may be a drill-bit or a stabilizer and between this point and the tool there may be a wellbore directional control system.
[0094] As shown in FIG. 10 , dynamic position sensor means comprising a pulse head ( 950 ) and a spring ( 960 ) provide for pressure signals detected at surface or downhole. FIG. 10 also shows the stabilizing blocks ( 63 ) are constructed identically to the cutter blocks ( 62 ), except that in place of cutter elements ( 60 ) there is a surface which is hard faced ( 61 ) or coated with a hard abrasion-resistant material.
[0095] The hard faced surfaces of the stabilizer expansion blocks act to stabilize the drill string and eliminate some of the problems associated with the loss of directional control above the underreamer when the diameter in said zone is equal to that of the underreamer or greater than the pilot hole. Likewise, the tool can be used to expand or enlarge the diameter of metal tubes by deformation of the latter in the wellbore. In this case, the tool body facilitates the operation of expanding or enlarging the diameter of the expandable casing and is connected to the downhole assembly by means of a screw connection in said body.
[0096] The stabilizer module may be directly or indirectly connected to the underreamer and hard-wired accordingly ( 74 a ) to send data from the processor ( 68 ) to the transponder ( 72 ) through the mud-pulser ( 56 ) to surface.
[0097] It is to be noted that the following description of the cutter means is equally applicable to the structure and function of the stabilizer and expansion means in the uphole section ( 61 ) of the tool, with due allowance for the absence of cutter elements ( 92 ).
[0098] A set of cutters comprises at least one cutter block ( 62 ) carrying a plurality of cutter elements ( 92 ) directed outwardly of the tool body ( 52 ). The cutter block is received within the tool body in a cutter block chamber ( 94 ) having an open mouth, and the cutter is extendable from the chamber through the chamber mouth with the cutter elements projecting from the tool body, and retractable back into the chamber. A seal ( 104 ) is provided around the cutter block at the mouth of the receiving chamber ( 94 ).
[0099] As noted above, in one embodiment the tool is provided with means for extending and retracting the cutter block from and into the cutter block chamber, such means may comprise a power mechanism ( 84 ) in the tool body in engagement with driven teeth ( 86 ) on the cutter block. Motor means ( 80 ) are provided for extending and retracting the cutter block, and microprocessor control means for the motor means are both mounted within the tool body. The microprocessor control means is suitably adapted to receive bore dimension information from the caliper means ( 66 ) and to control the cutter block extension in response thereto. A mechanical lock is provided by means of a locking collet finger ( 96 ), which can be located into one of a plurality of retaining lip grooves ( 98 ) by travelling lock ( 100 ), which is located by sealing collar ( 102 ). The tool may be activated by means of electronic signal sent by mud-pulse and decoded or by other means using fiber-optics or wireless transmission.
[0100] Hydraulic locking means may be provided to resist retraction of the extended cutter block ( 62 ) into the cutter block chamber ( 94 ) when the extension of the cutter block is opposed by external pressure. This may comprise a port (not shown) open to a source of drilling fluid (passage 90 ) onto the travelling lock ( 100 ) immediately behind the cutter block.
[0101] The tool normally comprises a plurality of such cutter blocks ( 62 ), arranged symmetrically around the tool. Two cutter blocks are on opposite sides of the tool, three blocks are separated by 120 degrees, four by 90 degrees, and six by 60 degrees. Additionally, a plurality of such cutter blocks are arranged at longitudinally separated positions so as to provide for a plurality of cutter block housings further detailed in FIG. 11 . In operation, the underreaming tool ( 50 ) is typically rotated on the drill string as well as being moved axially along the wellbore.
[0102] In accordance with an embodiment of the invention, shown in FIG. 9 , the cutter block is provided with an internal flowbore ( 110 ) leading drilling fluid from a through passage ( 90 ) to an external nozzle ( 112 ) among the cutter elements ( 92 ). The source of drilling fluid may be the rig pumps via the drill-string ( 30 ) to the passage ( 90 ) for the flow of drilling fluid from the drill string to the drill bit. In another embodiment, as shown in FIG. 10 , the tool body may be provided with an internal flowbore ( 114 ) leading drilling fluid from passage ( 90 ) to an external nozzle ( 116 ) adjacent the set of cutters. In each embodiment, the nozzle provides an optimized fluid flow that can help to keep the cutters clean and prevent the build-up of clogging debris from the underreaming operation, remove such material altogether from the underreaming zone, and provide a cooling and lubricating function for the cutters.
[0103] In yet another embodiment FIG. 10 shows an additional or alternate component a translatable mandrel or axial sleeve with position sensing ( 910 ) which may also have a profile or groove to engage expandable blocks ( 62 ) to act as a seal or lock or simply to engage expandable blocks and move them radially or laterally outward and also shows additional or alternate component 115 which can be an expandable bit configured with or without reaming capability to reduce downtime and uncertainty.
[0104] In yet another embodiment of FIG. 10 corresponding to certain components of FIGS. 8 and 9 , sealing collar 102 may be used to house further sensors or the sensors 96 a , 98 a may be used to detect the position of the mandrel.
[0105] FIG. 11 shows a further embodiment of the tool wherein a dynamic positional indicator is placed additionally or alternatively in a separate module to the set of cutters shown at the downhole end and a further set of stabilizers are shown at the uphole end, both sets suitably housed in modules. Such an embodiment comprises more than one set of expandable cutter blocks ( 62 and 62 ) integrated within independent modules that are screwed to each other in order to reduce drilling downtime.
[0106] FIGS. 12 and 13 show a detail of a dynamic position detector with and without a pulse head of one embodiment of the tool or apparatus showing the expansion elements constituted by a set of cutter blocks and a further expandable bit replacing the second set of cutter blocks. The signal or position is detected according to the position so that for a 14¾″-17½″ tool it could be configurable and extended to radial positions between 12¼″ and 14¾″. Generally such reamer positions are dependent on the pass through ID of casing and are expressed as increase in diameter relative to the bit size or reamer body size. Accordingly such expressions are generally in the order of 1″, 1.25″, 1.375″, 1.5″, 1.875″, 2.5″, 2.75″, 3″, 3.5″, 3.875″ and 4″ and so on. Other sizes are in the order of 0.5″, 0.75″ and so on.
[0107] FIGS. 14 and 15 detail a preferred embodiment with two locations for dynamic position detection contained within and partly without respectively of expandable cutter assembly.
[0108] FIGS. 16 , 17 show different configurations of a dynamic pulse head ( 950 ) for position detection with a spring ( 960 ) and compression/expansion chamber ( 980 ) with valve or pressure sensor ( 990 ). Additionally or alternatively, pressure or flow may be used to move the pulse head and thus create a series of clear and detectable pressure or flow signals corresponding to radial positions which are used to sense or indicate the block position.
[0109] In yet another embodiment a bending moment sensor may detect bending moments on the tool allowing for activation forces to be optimized by increasing or decreasing activation forces. The bending moment sensor may show that further activation force is required or lower force or that parameters should be changed such as the angle, rop, WOB, FLOW, directional control system blades. Optimal configurations of the invention are envisaged based on application needs.
[0110] A pulse head may travel through a number of rings and thus create a number of pulses related to position. For example, 1 pulse may be deactivated, 2 pulses 1 inch extended, 3 pulses 2 inches extended and so on.
[0111] Additionally or alternatively the reverse is also possible as is a further embodiment wherein the duration of the pulse may indicate positional data. For example, a long pulse indicates activation while a short pulse is deactivated or the alternate is possible. Further pulse encoding may be planned dependent on the type of frequency and duration and other pulsers that may be in the hole as is the case when directional or LWD/MWD companies are providing such measurements.
[0112] A series of pulses configurable by the user may be advantageous in detection and can be configurable to avoid interference with other signals in the mud column. Additionally or alternatively the interference may be electronic in which case means are provided to avoid such interference. Such means can be based on shielding, noise cancellation, circuitry configuration or component selection, frequency modulation, amplitude modulation, carrier waves, electro magnetic, sonic, etc.
[0113] FIG. 18 shows where the pulse head is connected to a mandrel which moves up or down the housing ( 975 ) which may if required be further contained within the body of the tool. In yet another embodiment of FIG. 18 , the mandrel may have a profile to engage with the expandable block, or a profile to engage with body or may simply engage with the expandable block.
[0114] FIG. 19 shows an embodiment wherein the blocks are connected to a chamber and dynamic position indicator ( 910 ) and further additional or alternate position sensing means located as ( 98 ) and ( 96 ) in relation to ( 910 ). The positional sensing means are generally located in the tool or cutter block or mandrel in a chamber but in an alternative configuration of the tool may be placed within the cutter block itself in the most radially extended zone among the cutting elements or linked to a nozzle opening to the wellbore. Other embodiments are for example, a pressure sensor may detect chamber pressure. Additionally or alternatively the sensing means may be located below a sealed area or within a seal area.
[0115] As shown in FIG. 20 and yet another embodiment leading drilling fluid from a through passage ( 90 ) to an external flow path ( 970 ) wherein a pulse head ( 950 ) may be driven by a solenoid or motor powered. The source of drilling fluid may be the rig pumps via the drill-string ( 30 ) to the passage ( 90 ) for the flow of drilling fluid from the drill string to the drill bit.
[0116] As shown in FIG. 21 and yet another embodiment leading drilling fluid from a through passage ( 90 ) to an oscillating pulser ( 990 ) wherein one or more discs ( 991 ) may be driven by fluid flow, a solenoid or motor powered to dynamically create pressure pulses to detect, monitor or indicate radial or longitudinal positional status. The discs may be open, close, partially open or closed and configured to operate at the desired flow, rpm or oscillation with the objective of providing positional indication. The source of drilling fluid may be the rig pumps via the drill-string ( 30 ) to the passage ( 90 ) for the flow of drilling fluid from the drill string to the drill bit.
[0117] Those skilled in the art will appreciate that the examples of the invention given by the specific illustrated and described embodiments show a novel underreaming tool and apparatus integrated with a caliper and accompanied by a method for underreaming verification and measuring underreamed wellbore diameter measurements using calibrated downhole fluid property measurements for accurate wellbore diameter measurements. A further embodiment includes a sensor for measuring the position of extendable blocks. While a further embodiment incorporates a vibration measurement sensor. Consequently, numerous variations are possible to achieve the purpose of the invention which is to improve drilling efficiency and provide certainty whenever a desired underreamed wellbore diameter is required. These embodiments are not intended to be limiting with respect to the scope of the invention. Substitutions, alterations and modifications not limited to the variations suggested herein may be made to the disclosed embodiments while remaining within the purpose and scope of the invention.
|
A dynamic position sensing Apparatus or Method is used to underream an oil or natural gas well with a variable gauge positioning system incorporating underreamer position or diameter sensing means.
| 4
|
FIELD OF THE INVENTION
The present invention describes novel 5-aryl-4-(5-substituted 2,4-dihydroxyphenyl)-1,2,3-thiadiazole derivatives, potentially useful in biomedicine as active ingredients of pharmaceutical preparations due to their ability to inhibit Hsp90 chaperone participating in cancer-disease progression. The invention also relates to new intermediate compounds required for the synthesis of target thiadiazoles.
BACKGROUND OF THE INVENTION
Molecular chaperones are protein machines that are responsible for the correct folding, stabilization, and function of other proteins in the cell. Exposure of cells to environmental stress, including heat shock, alcohols, heavy metals or oxidative stress, results in the cellular accumulation of these chaperones, commonly known as heat shock proteins (Hsp's). Heat-shock protein 90 (Hsp90) constitutes about 1-2% of total cellular proteins and is usually present in the cell as a dimer. It is a molecular chaperone responsible for ATP-depended folding, stability and function of many “client” proteins that are involved in the development and progression of cancer. These client proteins include ErbB2, c-Raf, Cdk4, mutant p53, hTERT, Hifl-α, and the estrogen/androgen receptors. Inhibition of Hsp90 causes the simultaneous, combinatorial destabilization and degradation of the oncogenic client proteins, leading in turn to a multiprolonged attack on all of the hallmark traits of cancer, including unrestricted proliferation and survival, invasion, metastasis and angiogenesis. It is generally thought that cancer cells are more susceptible to Hsp90 inhibition than are the corresponding normal cells (P. Workman (2004), Trends Mol. Med., 10, 47-51). On the other hand, therapeutic selectivity of Hsp90 inhibitors is the stressed condition of cancer cells, due both to oncogenic mutations and deregulated signalling and also to environmental factors such as hypoxia, acidosis and nutrient deprivation. Moreover, it has been reported that the Hsp90 found in malignant cells exists predominantly in a superchaperone complex that binds Hsp90 inhibitors much more effectively than the uncomplexed form that is mainly present in healthy cells (B. W. Dymock et al, (2004), Expert Opin. Ther. Patents, 14, 837-847).
The ATPase activity of Hsp90 chaperone can be inhibited with some selectivity by natural product antibiotics such as geldanamycin and radicicol (S. M. Roe et al, (1999), J Med Chem 42, 260-266). Both of those compounds bind to the N-terminal domain of Hsp90 and inhibit the intrinsic ATPase activity.
Geldanamycin showed activity in human tumour xenograft models but this compound proved to be too hepatotoxic for clinical development. However, the modified versions of geldanamycin—17-allylamino-17-demethoxy-geldanamycin (17-AAG) and 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG) retain the property of Hsp90 inhibition and have significantly less hepatotoxicity than geldanamycin (U.S. Pat. No. 4,261,989, publ. 1981). 17-AAG is currently being evaluated in clinical trials.
Radicicol is macrocyclic antibiotic isolated from Monosporium Bonorden . Radicicol is more potent inhibitor of Hsp90 ATPase activity than geldanamycin or 17-AAG (T. W. Schulte et al, (1998) Cell Stress Chaperones 3, 100-108). Unfortunately, the radicicol structure has some inherent limitations, including the epoxide moiety, keto group ant the propensity to undergo Michael addition reactions. Radicicol lacks antitumour activity in vivo due to the unstable chemical nature of the compound. Oxime derivatives of radicicol (known as KF25706 and KF58333) have been synthesized and retain the Hsp90 inhibitory activity of radicicol. Moreover KF25706 has been shown to exhibit in vivo antitumour activity in human tumour xenograft models (S. Soga et al (1999) Cancer Res, 59, 2931-8; U.S. Pat. No. 6,239,168; U.S. Pat. No. 6,316,491; U.S. Pat. No. 6,635,662). However, no radicicol derivative has progressed to clinical development.
It is also known that coumarin, novobiocin, and cisplatin bind to the C-terminal domain of Hsp90 resulting in the inhibition of ATPase function (G. A. Holdgate (1997) Biochemistry 36, 9663-9673; R. J. Lewis (1996) Embo J 15, 1412-1420; M. G. Marcu et al (2000) J. Biol. Chem., 275, 37181-37186; M. G. Marcu et al (2003) Curr. Cancer Drug Targets, 3, 343). Therefore, both binding sites of Hsp90 are important to Hsp90 chaperone properties.
Significant consideration in the patent literature is given to various synthetic small molecule Hsp90 inhibitors. First purine-based inhibitors (PU3 and PU24FCl) have been synthesized based on rational drug design with the aid of the X-ray crystal structure (EP 1335920, G. Chiosis et al (2001) Chem. Biol. 8, 289-299). These agents were shown to result in the degradation of signaling molecules, including ERBB2, and to cause cell cycle arrest and differentiation in breast cancer cells. Recently, S. R. Kasibhatla et al have reported about novel purine derivatives with amine, sulfide, sulfoxide and sulfone moieties (WO 03037860; U.S. Pat. No. 7,241,890; U.S. Pat. No. 7,138,401). Some of these compounds inhibit Hsp90 chaperone in nanomolar potency. Nowadays purine-based inhibitors of Hsp90 attract scientific attention (WO2006075095, EP1838322).
Another class of synthetic Hsp90 inhibitors are presented by structural purine analogs—pyrazolopyrimidines, pyrrolopyrimidines and triazolopyrimidines. These compounds were synthesized and tested by S. R. Kasibhatla et al (U.S. Pat. No. 7,148,228; U.S. Pat. No. 7,138,402, U.S. Pat. No. 7,129,244, EP1869027).
Various 3,4-diarylpyrazole derivatives bearing resorcinol moiety have been selected and prepared by high throughput screening of a combinatorial library at the Institute of Cancer Research. Some of such derivatives (known as CCT 018159, VER 49009) showed very high Hsp90 inhibition affinity (K. M. J. Cheung et al (2005) Bioorg. Med. Chem. Lett., 15, 3338-3343; B. W. Dymock et al (2005) J. Med. Chem., 48, 4212-4215; U.S. Pat. No. 7,247,734; EP 1456180). A number of 3-arylpyrazole-4-piperazine derivatives (X. Barril (2006) Bioorg. Med. Chem. Lett., 16, 2543-2548), as well as 3-aryl-4-aryloxypyrazoles (patent JP 2005225787) are synthesized and exhibited Hsp90 binding affinity.
It is also patented that pyrazole scaffold in 3,4-diarylpyrazoles can be replaced by other 5-membered ring, such as isoxazole (EP1611112) or triazole (WO2005000300, WO2007139952).
Also a large number of small-molecule synthetic inhibitors of Hsp90 chaperone have been synthesized and evaluated. This is different pyrazole (US2007112192, EP1567151, US2007191445, EP1620090, JP2006306755), triazole (US2007155809, WO2007139956, WO2008021364, WO2006055760, WO2007139968, WO2007139967, WO2007139952, US2006167070), quinazolines (EP1885701, WO2006122631), isoindoles (WO2008044034, EP 1869042) and hydroxybenzamides (WO2006109075).
Despite the fact that a large number of different Hsp90 inhibitors have been synthesized to date, only few of them are clinically tested. There still remains a great need of new potent Hsp90 inhibitors which offer one or more following advantages: improved activity, selectivity, solubility, reduced toxicity and side-effects, reduced cost of synthesis and so on.
Therefore, the creation of novel Hsp90 chaperone inhibitors is still an important task.
No data on synthesis of invention compounds 5-aryl-4-(5-substituted 2,4-dihydroxyphenyl)-1,2,3 thiadiazoles and intermediate compounds required for the synthesis of invention compounds was found in patent and non-patent literature.
SUMMARY OF THE INVENTION
This invention describes new 5-aryl-4-(5-substituted 2,4-dihydroxyphenyl)-1,2,3-thiadiazoles with general formula (I)
wherein
R is H, Cl, Br, I, CH 3 , C 2 H 5 , OCH 3 ;
R 1 and R 2 are the same or different substituents, selected from the group, consisting of H, CH 3 , C 2 H 5 , C 3 H 7 , C 4 H 9 , OCH 3 , OC 2 H 5 , OC 3 H 7 , O(CH 2 ) 2 O, O(CH 2 ) 3 O.
The objects of the invention are also the non-toxic, pharmaceutically acceptable salts of the thiadiazoles of the general formula (I). They include all salts which retain activity comparable to original compounds and do not attain any harmful and undesirable effects. Such salts are obtained from compounds with general structural formula (I) by mixing their solution with pharmacologically acceptable non-toxic organic and inorganic acids, such as hydrogen chloride, butane diacid, citric acid, tartaric acid, phosphoric acid, sulphuric acid and other.
Examples of the invented compounds are compounds, selected from the group comprising:
4-[6-(4-chloro-1,3-dihydroxyphenyl)]-5-[4-(4-methoxyphenyl)]-1,2,3-thiadiazole; 4-[6-(4-chloro-1,3-dihydroxyphenyl)]-5-[4-(4-ethoxyphenyl)]-1,2,3-thiadiazole; 4-[6-(4-chloro-1,3-dihydroxyphenyl)]-5-[4-(4-methylphenyl)]-1,2,3-thiadiazole; 4-[6-(4-chloro-1,3-dihydroxyphenyl)]-5-[4-(3,4-dimethoxyphenyl)]-1,2,3-thiadiazole; 4-[6-(4-ethyl-1,3-dihydroxyphenyl)]-5-[4-(4-ethoxyphenyl)]-1,2,3-thiadiazole;
where all above listed compounds exhibit Hsp90 inhibitor properties.
The new intermediate compounds described below which could be used for the synthesis of thiadiazoles with general formula (I) are also subject of this invention.
DETAILED DESCRIPTION OF THE INVENTION
New compounds of the invention can be obtained according to general synthesis scheme:
Synthesis of the starting materials (compounds with general formula 1) was accomplished by procedure described by B. W. Dymock, X. Barril, P. A. Brough, J. E. Cansfield, A. Massey, E. McDonald, R. E. Hubbard, A. Surgenor, S. D. Roughley, P. Webb, P. Workman, L. Wright, M. J. Drysdale (2005) J. Med. Chem., 48, 4212-4215. Compounds 1 reacted with hydrazine hydrate in boiling ethanol and formed the corresponding hydrazones 2. Latter derivatives underwent smoothly cyclization with thionyl chloride to form 5-aryl-4-(5-substituted 2,4-dihydroxyphenyl)-1,2,3-thiadiazoles 3 in high yields.
BRIEF DESCRIPTION OF THE DRAWINGS
To illustrate the main characteristics of the new compounds this description contains:
FIG. 1 . Determination of the compound of general formula I, namely 4-(5-chloro-2,4-dihydroxyphenyl)-5-(4-ethoxyphenyl)-1,2,3-thiadiazole (3b) binding to Hsp90N by isothermal titration calorimetry. Raw isothermal titration calorimetric data is shown.
FIG. 2 . Determination of the compound of general formula I, namely 4-(5-chloro-2,4-dihydroxyphenyl)-5-(4-ethoxyphenyl)-1,2,3-thiadiazole (3b) binding to Hsp90N by isothermal titration calorimetry. Integrated isothermal titration calorimetric data is shown.
FIG. 3 . A typical cell survival curve generated for compound of general formula I, namely 4-(5-ethyl-2,4-dihydroxyphenyl)-5-(4-ethoxyphenyl)-1,2,3-thiadiazole (3e) in U2OS cells. Such curves were used for the determination of compound concentrations where cell growth is reduced by 50% (GI 50 ).
EMBODIMENTS OF THE INVENTION
Represented below are specific examples of invention compounds and synthesis thereof, including intermediate compounds required for target compound. These examples are presented only for illustrative purpose of the invention; they do not limit the scope of the invention.
Example 1
Production of the Intermediate Compound 1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-methoxyphenyl)ethanone hydrazone (2a)
Hydrazine hydrate (0.166 ml, 3.42 mmol) is added to a solution of 1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-methoxyphenyl)ethanone (1a) (0.5 g, 1.71 mmol) in 95% ethanol (5 ml). The mixture is heated under reflux for 7 hours. Solvent is concentrated in vacuo, the residue treated with water, filtered of and recrystallyzed from 2-propanol.
Yield 76%, yellow solid, mp 143-145° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 3.72 (3H, s, OCH 3 ), 4.00 (2H, s, CH 2 ), 6.40 (1H, s, ArH), 6.71 (2H, br.s. NH 2 ), 6.88 (2H, d, J=8.7 Hz, ArH), 7.15 (2H, d, J=8.7 Hz, ArH), 7.26 (1H, s, ArH), 9.92 (1H, br.s. OH), 13.56 (1H, s, OH).
13 C NMR (75 MHz, DMSO-d 6 ) δ ppm 28.6, 54.9, 104.1, 109.2, 113.0, 114.0, 127.2, 128.0, 129.1, 149.3, 153.2, 157.7, 158.4.
Example 2
Production of the Intermediate Compound 1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-ethoxyphenyl)ethanone hydrazone (2b)
Synthesis was carried out according to the description of Example 1, starting from 1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-ethoxyphenyl)ethanone 1b (0.52 g, 1.71 mmol).
Yield 97%, yellow solid, mp 163-165° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 1.28 (3H, t, J=6.6 Hz, CH 3 ), 3.94 (2H, q, J=6.6 Hz, OCH 2 ), 3.94 (2H, s, CH 2 ), 6.39 (1H, s, ArH), 6.70 (2H, br.s. NH 2 ), 6.84 (2H, d, J=8.7 Hz, ArH), 7.11 (2H, d, J=8.7 Hz, ArH), 7.24 (1H, s, ArH), 10.18 (1H, br.s. OH), 13.55 (1H, s, OH).
Example 3
Production of the Intermediate Compound 1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-methylphenyl)ethanone hydrazone (2c)
Synthesis was carried out according to the description of Example 1, starting from 1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-methylphenyl)ethanone 1c (0.47 g, 1.71 mmol).
Yield 74%, yellow solid, mp 182-184° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 3.33 (3H, s, CH 3 ), 3.79 (2H, s, CH 2 ), 6.41 (1H, s, ArH), 6.75 (2H, br.s. NH 2 ), 7.08-7.17 (4H, m, ArH), 7.28 (1H, s, ArH), 9.99 (1H, br.s. OH), 13.50 (1H, s, OH).
Example 4
Production of the Intermediate Compound 1-(5-chloro-2,4-dihydroxyphenyl)-2-(3,4-dimethoxyphenyl)ethanone hydrazone (2d)
Synthesis was carried out according to the description of Example 1, starting from 1-(5-chloro-2,4-dihydroxyphenyl)-2-(3,4-dimethoxyphenyl)ethanone 1d (0.55 g, 1.71 mmol).
Yield 83%, yellow solid, mp 152-154° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 3.71 (3H, s, OCH 3 ), 3.73 (3H, s, OCH 3 ), 3.99 (2H, s, CH 2 ), 6.40 (1H, s, ArH), 6.65 (2H, br.s. NH 2 ), 6.68-6.94 (3H, m, ArH), 7.28 (1H, s, ArH), 10.02 (1H, br.s. OH), 13.52 (1H, s, OH).
Example 5
Production of the Intermediate Compound 1-(5-ethyl-2,4-dihydroxyphenyl)-2-(4-ethoxyphenyl)ethanone hydrazone (2e)
Synthesis was carried out according to the description of Example 1, starting from 1-(5-ethyl-2,4-dihydroxyphenyl)-2-(4-ethoxyphenyl)ethanone 1e (0.51 g, 1.71 mmol).
Yield 60%, yellow solid, mp 63-64° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 1.17 (3H, t, J=7 Hz, CH 3 ), 1.39 (3H, t, J=7.5 Hz, CH 3 ), 2.42 (2H, q, J=7 Hz, CH 2 ), 3.72 (2H, q, J=7.5 Hz, OCH 2 ), 3.99 (2H, s, CH 2 ), 6.32 (1H, s, ArH), 6.54 (2H, br.s. NH 2 ), 6.75 (2H, d, J=8.7 Hz, ArH), 7.07 (2H, d, J=8.7 Hz, ArH), 7.21 (1H, s, ArH), 9.90 (1H, br.s. OH), 13.50 (1H, s, OH).
Example 6
Preparation of 4-(5-chloro-2,4-dihydroxyphenyl)-5-(4-methoxyphenyl)-1,2,3-thiadiazole (3a)
1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-methoxyphenyl)ethanone hydrazone (2a) (0.1 g, 0.33 mmol) is carefully added to thionyl chloride (1 ml). The reaction mixture is stirred at room temperature for 2 hours. The excess of thionyl chloride is evaporated under reduced pressure, the residue is dissolved in chloroform (10 ml). The organic layer is washed twice with NaHCO 3 (sat. aq. 10 ml), then with water (15 ml), dried over Na 2 SO 4 , concentrated in vacuo. The residue was purified by dry column chromatography (D. S. Pederson, C. Rosenbohm, (2001) Synthesis, 16, 2431-2434).
Yield 95%, brown amorphous solid, mp 87-89° C.
1 H NMR (300 MHz, CDCl 3 ) δ ppm 3.93 (3H, s, OCH 3 ), 5.76 (1H, br.s. OH), 6.81 (1H, s, ArH), 7.05 (2H, d, J=8.7 Hz, ArH), 7.17 (1H, s, ArH), 7.39 (2H, d, J=8.7 Hz, ArH), 10.20 (1H, s, OH).
13 C NMR (75 MHz, DMSO-d 6 ) δ ppm 55.2, 103.9, 109.9, 110.3, 114.5, 120.1, 129.6, 131.4, 151.9, 153.4, 154.6, 155.2, 160.2
Example 7
Preparation of 4-(5-chloro-2,4-dihydroxyphenyl)-5-(4-ethoxyphenyl)-1,2,3-thiadiazole (3b)
Synthesis was carried out according to the description of Example 6, starting from 1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-ethoxyphenyl)ethanone hydrazone 2b (0.11 g, 0.33 mmol).
Yield 80%, brownish amorphous solid, mp 132-134° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 1.30 (3H, t, J=6.9 Hz, CH 3 ), 4.01 (2H, q, J=6.9 Hz, OCH 2 ), 5.92 (1H, br.s. OH), 6.71 (1H, s, ArH), 6.93 (2H, d, J=9 Hz, ArH), 7.24 (1H, s, ArH), 7.29 (2H, d, J=9 Hz, ArH), 10.23 (1H, s, OH).
13 C NMR (75 MHz, DMSO-d 6 ) δ ppm 15.2, 53.9, 104.7, 110.7, 111.1, 115.6, 120.8, 130.4, 132.2, 152.8, 154.2, 155.4, 156.0, 160.3.
Example 8
Preparation of 4-(5-chloro-2,4-dihydroxyphenyl)-5-(4-methylphenyl)-1,2,3-thiadiazole (3c)
Synthesis was carried out according to the description of Example 6, starting from 1-(5-chloro-2,4-dihydroxyphenyl)-2-(4-methylphenyl)ethanone hydrazone 2c (0.10 g, 0.33 mmol).
Yield 94%, brown amorphous solid, mp 69-71° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 2.31 (3H, s, CH 3 ), 5.57 (1H, br.s. OH), 6.70 (1H, s, ArH), 7.20-7.27 (4H, m, ArH), 7.29 (1H, s, ArH), 10.22 (1H, s, OH).
13 C NMR (75 MHz, DMSO-d 6 ) δ ppm 21.5, 104.7, 110.7, 111.0, 126.0, 128.8, 130.3, 132.3, 140.2, 152.9, 154.7, 155.4, 156.0.
Example 9
Preparation of 4-(5-chloro-2,4-dihydroxyphenyl)-5-(3,4-dimethoxyphenyl)-1,2,3-thiadiazole (3d)
Synthesis was carried out according to the description of Example 6, starting from 1-(5-chloro-2,4-dihydroxyphenyl)-2-(3,4-dimethoxyphenyl)ethanone hydrazone 2d (0.11 g, 0.33 mmol).
Yield 96%, brownish amorphous solid, mp 117-119° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 3.60 (3H, s, OCH 3 ), 3.77 (3H, s, OCH 3 ), 5.78 (1H, br.s. OH), 6.73 (1H, s, ArH), 6.94-6.98 (3H, m, ArH), 7.26 (1H, s, ArH), 10.21 (1H, s, OH).
13 C NMR (75 MHz, DMSO-d 6 ) δ ppm 55.2, 55.5, 103.9, 109.9, 110.5, 111.4, 111.9, 120.2, 121.6, 131.6, 148.5, 149.9, 152.2, 153.6, 154.7, 155.5.
Example 10
Preparation of 4-(5-ethyl-2,4-dihydroxyphenyl)-5-(4-ethoxyphenyl)-1,2,3-thiadiazole (3e)
Synthesis was carried out according to the description of Example 6, starting from 1-(5-ethyl-2,4-dihydroxyphenyl)-2-(4-ethoxyphenyl)ethanone hydrazone 2e (0.10 g, 0.33 mmol).
Yield 65%, brown amorphous solid, mp 65-66° C.
1 H NMR (300 MHz, DMSO-d 6 ) δ ppm 1.08 (3H, t, J=6.6 Hz, CH 3 ), 1.319 (3H, t, J=7 Hz, CH 3 ), 2.44 (2H, q, J=6.6 Hz, CH 2 ), 4.03 (2H, q, J=7.5 Hz, OCH 2 ), 5.87 (1H, br.s. OH), 6.47 (1H, s, ArH), 6.94 (2H, d, J=7.5 Hz, ArH), 7.99 (1H, s, ArH), 7.31 (2H, d, J=7.5 Hz, ArH), 10.02 (1H, s, OH).
Compounds of general formula (I) bearing different substituents in aromatic rings (R═Br, I, OCH 3 ; R 1 , R 2 ═OC 3 H 7 , C 2 H 5 , C 3 H 7 , C 4 H 9 , O(CH 2 ) 2 O, O(CH 2 ) 3 O and others) can be synthesized in a similar way to compounds 3a-e starting from corresponding 1-(5-substituted-2,4-dihydroxyphenyl)-2-(3,4-disubstitutedphenyl)ethanones.
Example 11
Determination of Binding Constants by Isothermal Titration Calorimetry
Inhibitor binding to the N-terminal domain of Hsp90 were determined by isothermal titration calorimetry (Chaires, J. B. 2008. Annu. Rev. Biophys. 37: 135-51). FIG. 1 shows a representative experimental data—raw isothermal titration calorimetry experiment of compound 3b binding to Hsp90N (50 mM Hepes buffer, 100 mM NaCl, pH 7.5, 37° C.). Protein concentration in the calorimeter cell was 6 μM. Ligand concentration in the syringe was 120 μM. FIG. 2 shows the same data as in FIG. 1 in the integrated form. The binding constant was determined to be 1.3×10 8 M −1 with stoichiometry of 0.97. This is equivalent to dissociation constant equal to 7.5 nM. Such strong binding constants are at the verge of instrument capabilities. Therefore, they may be slightly underestimated. Very steep isothermal titration curves show very tight binding and strong potential as candidate compounds to inhibit Hsp90 activity in vitro.
The values of various compound binding constants to both protein constructs (the N-terminal domain, Hsp90N, and the full length Hsp90F) obtained at 37° C. are listed below. Dissociation constants (K d , determined by isothermal titration calorimetry) of compound binding to the N-terminal domain of Hsp90 (Hsp90N) were: for compound 3a was 0.016±0.004 μM, for compound 3b was 0.035±0.008 μM, for compound 3c was 0.017±0.006 μM, for compound 3d was 0.034±0.003 μM, and for compound 3e with Hsp90N was 0.029±0.002 μM. Similarly, the K d s of the compound binding to the full Hsp90 protein (Hsp90F) were: for compound 3a was 0.039±0.018 μM, for compound 3b was 0.014±0.001 μM, for compound 3c was 0.011±0.007 μM, for compound 3d was 0.057±0.002 μM, and for compound 3e was 0.031±0.005 μM.
Example 12
Determination of Growth Inhibition Constants (GI 50 )
The growth inhibition constants of the compounds were determined in two cancer cell lines: U2OS (osteosarcoma) and HeLa (cervical carcinoma). Cells were maintained in DMEM (HeLa) and a 50-50% mixture of DMEM and F-12 media (U2OS) supplemented with 10% fetal bovine serum. Stock solutions (20 mM) of the tested compounds were prepared in 100% dimethyl-sulfoxide (DMSO). Cells, cultured in 24-well plates, were subjected to a range of concentrations of the compounds (50 mM-0.05 mM) at 0.25% DMSO. After 3 days, cell viability was assayed using XTT (sodium salt of 2,3-bis[2-Methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide inner salt) and PMS (phenazine methosulfate) reagents (Scudiero et al. 1988. Cancer Res. 48, 4827-4833). Stock solutions of XTT (1 mg/ml) and PMS (1.53 mg/ml) were prepared in Hank's buffered saline (HBS). Culture medium in each well was replaced by 100 μl of OptiMEM media (Life technologies) containing 35 μg/ml XTT and 0.27 μg/ml PMS. Cells were returned to the incubator for 15-20 min. Quantity of viable cells in each well was evaluated spectrophotometrically measuring the absorbance of XTT formazan at 470 nm. Each experiment was run in duplicate.
The values of various compound growth inhibition constants to U2OS (osteosarcoma) cell line and were the following: for compound 3a was 8.4±1.2 μM, for compound 3b was 15.1±3.4 μM, for compound 3c was 7.1±0.1 μM, for compound 3d was 11.5±0.1 μM, and for compound 3e was 0.65±0.08 μM. Similarly, the GI 50 constants for HeLa (cervical carcinoma) cell line were: for compound 3a was 2.5±0.1 μM, for compound 3b was 4.2±0.4 μM, for compound 3c was 3.3±0.1 μM, for compound 3d was 3.6±0.3 μM, and for compound 3e was 0.70±0.04 μM. Such strong compound potency in inhibiting cancerous cell growth and survivability indicate compound potential to become lead compounds and candidates for therapeutic anticancer treatment.
The above described new compounds are effective binders of Hsp90 target and they efficiently inhibit cancerous cell growth. The potency of compounds is comparable or better than other patented compounds. Synthesis of new compounds is significantly easier and less expensive than other similar patented compounds with comparable potency.
|
Invention is related to novel compounds -5-aryl-4-(5-substituted 2,4-dihydroxyphenyl)-1,2,3-thiadiazoles with general formula (I). The compounds can be used in biomedicine as active ingredients in pharmaceutical formulations, because they inhibit Hsp90 chaperone which participate in cancer progression. This invention is also related to new intermediate compounds which are used for the synthesis of thiadiazoles of general formula (I).
| 2
|
The present invention concerns a multi-tap sampled data filtering system which uses a crossbar switch matrix to provide programmable tap delays.
In finite impulse response (FIR) and infinite impulse response (IIR) sampled data filtering systems, a sampled data signal is delayed, either through a chain of delay elements having interstitial taps or through multiple parallel delay elements. Delayed signals, taken at selected tap positions or at the output ports of the multiple delay elements, are multiplied by respective filter coefficient values and then added together by summing circuitry. In an FIR filter, the input signal to the filtering system is the signal that is applied to the delay elements, and the output signal is provided by the summing circuitry. In an IIR system, the input signal is added to the signal provided by the summing circuitry to produce the signal that is applied to the delay elements. This signal is also the output signal of the filter.
One type of filtering system has been difficult to implement economically as a sampled data filtering system. This type of filter is best visualized as a relatively long chain of delay elements having a relatively small number of taps which may have variable locations along the chain. A filter of this type may be used, for example, in a system for reducing multipath distortion such as an automatic ghost cancellation system in a television receiver.
In a first type of ghost cancellation filter, the video signal, contaminated by multipath or ghost signals, is delayed by successive stages of a fixed delay line, such as a charge transfer delay device (CTD). At the outputs of the delay line stages, the respective delayed signals are extracted, weighted by filter coefficient values and combined to form a psuedo-ghost signal suitable for canceling the ghost component of the contaminated video signal. In this type of filter there is a tap for every delay element and a filter coefficient multiplier for every tap. However, not all taps contribute to the filtered output signal, only those having non-zero filter coefficient values. A ghost cancellation filter of this type is described, for example, in U.S. Pat. No. 4,344,089 entitled "Ghost Cancelling System", which is hereby incorporated by reference.
A second type of filtering system is shown in the automatic ghost cancellation system of FIG. 1. In this system, contaminated video signals provided by a source 5 are applied to an IIR filter, which includes an adder 12 and an FIR filter 40. The IIR filter is responsive to the contaminated video signal to develop a psuedo-ghost signal having a polarity which is opposite to that of the contaminating ghost signal. This psuedo-ghost signal is added to the contaminated signal in the adder 12 to substantially cancel the ghost signal component of the video signal.
In the exemplary system shown in FIG. 1, up to three ghost signals in the input video signals are detected by a ghost detector 10. The detector 10 sets the amount of time delay provided by each of three variable delay elements 14, 16 and 18 to develop the psuedo-ghost signals for the three detected ghost signals, respectively. The ghost detector 10 also provides a signal to the filter coefficient generating circuitry 20 which, using this signal and the output signal of the adder 12, develops filter coefficient values for three multipliers 22, 24 and 26 coupled to the output ports of the delay elements 14, 16 and 18, respectively. The multipliers appropriately scale and reverse the polarity of the delayed main signal to develop the psuedo-ghost signals. The three psuedo-ghost signals are combined by the adders 28 and 30 to develop the signal which, when applied to the adder 12, cancels the three ghost signals from the input video signals. A ghost signal cancellation system similar to that shown in FIG. 1 is described in U.S. Pat. No. 4,542,408 entitled "Digital Deghosting System", which is hereby incorporated by reference.
In the ghost cancellation system shown in FIG. 1, the sampled data signal provided by the adder 12 is delayed by the three parallel delay elements 14, 16 and 18, the output ports of which may be considered to be the taps of a delay line. The amount of time delay provided by each of the delay elements is variable, thus, the position of each tap on the delay line is variable. To allow full variability of tap position, however, each of the delay elements 14, 16 and 18 should have sufficient memory to allow its associated tap to provide the longest possible time delay. Thus, this system uses three times the memory of the first described system. Even though it uses more memory, this filter configuration is preferred over the first described system for digital ghost cancellation systems because it uses a small number of multipliers, which are relatively complex digital devices.
SUMMARY OF THE INVENTION
The present invention is embodied in a sampled data signal filtering system. The system includes N serially connected delay elements and M sample scaling circuits, where N and M are both integers and M is less than N. A multi-port controllable switching network is configured to couple the output terminals of selected ones of the delay elements to input ports of respectively different ones of the sample scaling circuits.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 (prior art) is a block diagram of a ghost cancellation system useful for explaining an environment for using the present invention.
FIG. 2 is a block diagram of a portion of a sampled data filter embodying the present invention.
FIGS. 3 and 4 are block diagrams, partially in schematic diagram form, of alternate switching networks which may be used in the sampled data filter shown in FIG. 2.
DETAILED DESCRIPTION
In the drawings, broad arrows represent signal paths, i.e. connections for conveying analog signals or busses for conveying multiple-bit parallel digital signals. Line arrows represent connections for conveying analog signals or single bit digital signals. Depending on the processing speed of the devices, compensating delays may be required in certain of the signal paths and connections. One skilled in the art of digital signal processing circuit design will know where such delays are needed in a particular system.
FIG. 2 is a block diagram of circuitry which may be used in place of the FIR filter 40 shown in FIG. 1. The filter shown in FIG. 2 uses a single chain of delay elements τ 0 , τ 1 , . . . τ 383 and a crossbar switch 200 to realize the same function as the three programmable delay elements 14, 16 and 18, of the system shown in FIG. 1. Each of the delay elements, τ 0 through τ 383 , delays the samples applied to its input port by a fixed amount of time, for example, one period of the sampling clock signal. The samples applied to the input port of the filter and the samples available at the output port of each of the delay elements τ 0 through τ 383 are applied to respectively different input ports of the crossbar switch matrix 200. The samples provided by selected ones of the delay elements are applied to the input terminals of the multipliers 212, 214 and 216 by respectively selected switches in each of the columns of switch elements; SA0 through SA384, SB0 through SB384 and SC0 through SC384. An individual switch element is selected to couple its input samples to its associated output port by one of the signals SEL0 through SEL384, generated by the row select circuitry 210, and by one of the column select signals, C0LA, C0LB and C0LC.
The row select circuitry 210, may, for example, be the same as the address decoding circuitry used in a conventional 512 by 1 bit random access memory (RAM). In response to a signal ROW ADDR, provided by the ghost detector 10, the circuitry 210 activates one of the signals SEL0 through SEL384. When the signal provided by the row select circuitry 210 has stabilized, one of the column select signals, C0LA, C0LB or C0LC, also provided by the ghost detector 10, is pulsed to close the selected switch element.
FIG. 3 is a block diagram of a switch element suitable for use in a parallel-bit digital embodiment of the present invention. In FIG. 3, the output signal path of an arbitrary delay element, τ x , is shown as eight one-bit connections DX 0 through DX 7 and the output data path of the switch element is shown as eight one-bit connections MX 0 through MX 7 . Each of the input signal paths is coupled to a corresponding output signal path by an enhancement mode field effect transistor (FET) configured as a transmission gate. The source electrodes of the transistors Q 0 through Q 7 are connected to the respective input connections DX 0 through DX 7 , and the drain electrodes of the transistors Q 0 through Q 7 are connected to respective output connections MX 0 through MX 7 . The gate electrodes of the transistors Q 0 through Q 7 are connected together. In the first embodiment of the invention to be described, the interconnected gate electrodes of the transistors Q 0 through Q 7 are connected to the output terminal, Q, of a flip-flop 310. The data (D) and clock (CLK) input terminals of the flip-flop 310 are coupled to receive the respective row select signal (SELX) and column select signal (COLX) applied to the switch element. If the signal SELX is a logic zero when the signal COLX is strobed, the signal available at the Q output terminal is a logic zero, the transistors Q 0 through Q 7 are turned off and the input signal paths DX 0 through DX 7 are not connected to the output signal paths MX 0 through MX 7 . Conversely, if SELX is a logic one when the signal COLX is strobed, the signal available at the Q output terminal of flip-flop 310 is a logic one and the transistors Q 0 through Q 7 are turned on, connecting the input signal paths DX 0 through DX 0 to the respective output signal paths MX 0 through MX 7 .
In the system described above, the switch elements change state one column at a time as each of the three column select signals is strobed. Consequently, while the filter system is changing from its current transfer function to a new transfer function, it may pass through intermediate states in which it exhibits undesirable transfer functions. To prevent this from occurring, a second flip-flop 312 (shown in phantom) may be included in the circuitry for each switching element, in place of the connection A. The flip-flops 310 and 312 are in a master-slave relationship. While the new filter state is being stored in the flip-flop 310, as described above, the flip-flop 312 keeps the system operating in the old state. When the new state is fully established in the flip-flops 310 of all of the switching elements, a clock pulse CKF is simultaneously applied to all of the flip-flops 312, changing the state of the filter to implement the new transfer function.
It is contemplated that the separate row select connections SEL0 through SEL384 may be eliminated by configuring the flip-flops 310 of each column of switch elements as a shift register. In this contemplated embodiment of the invention, the row select circuitry 210 may, for example, include a shift register (not shown) having a number of stages equal to the number of rows of switch elements in the crossbar switch matrix. This shift register may be connected, via a multiplexer, (not shown) to the three column shift registers formed by the interconnected flip-flops 310. In this embodiment of the invention, the shift register stage or sample delay element to be connected to the multiplier input terminal is selected by the row select circuitry and which stores a logic one at the corresponding location in its internal shift register and logic zeroes at all other locations. This shift register is then clocked by the appropriate column select signal to transfer the selected switch states to the corresponding row locations in the appropriate column shift register. A pulse applied to the CKF input terminal of the flip-flop 312 then reconfigures the switch elements to change the transfer function of the filter. In FIG. 3, the interconnection of the flip-flops 310 as a shift register is shown by the phantom signal SELSH which is applied to the D input terminal of the flip-flop 310 and propogated to the flip-flop 310 of the next sequential switch element, as the signal SELSH', via the Q output terminal of the flip-flop 310.
FIG. 4 illustrates an alternative switch element circuit which may be used when the delay elements τ 0 through τ 383 are realized using a CTD.
A signal, DX, generated from the charge provided at a tap of the CTD is applied to the interconnected drain and source electrodes of two complementary FET's 402 and 404 respectively. The interconnected source and drain electrodes of the transistors 402 and 404 are connected to the output signal path MX. The gate electrodes of the complementary FET's 402 and 404 are connected to the respective Q and Q output terminals of a flip-flop 410. The FET's 402 and 404 are conditioned to conduct when the signals provided by the terminals Q and Q are logic one and logic zero, respectively, and conditioned to be non-conducting when the signals at the terminals Q and Q are logic zero and logic one, respectively.
The row select signal SELX and column select signal COLX are applied to the respective D and CLK input terminals of the flip-flop 410. As described in reference to the switch element shown in FIG. 3, the row select signal SELX is developed by the row select circuitry 210 and applied to the switch element. This row select signal is stored into the flip-flop 410 when the column select signal, COLX, is strobed. When the signal SELX is a logic zero, the signals at the Q and Q output terminals of the flip-flop 410 are logic zero and logic one respectively and both transistors are turned off so the signal path DX is not connected to the signal path MX. When SELX is a logic one, however, the signals at the Q and Q output terminals of the flip-flop 410 are logic one and logic zero signals, respectively, and the signal path DX is connected to the signal path MX. The switch configuration shown in FIG. 4 is preferred when analog signals are to be switched since the parallel arrangement of the complementary transistors 402 and 404 allows analog signals to be switched with only insignificant distortion, even when the output data path provides a significant capacitive load.
It is contemplated that the alternative embodiment of the switch element, described in reference to FIG. 3, involving the flip-flop 312 and the configuration of the flip-flop 310 as one stage in a shift register may be used with the switch element shown in FIG. 4. Moreover, it is contemplated that the single FET transmission gates Q 0 through Q 7 shown in FIG. 3 may be replaced by complementary FET transmission gates identical to the one shown in FIG. 4, or by any other circuitry which realizes a transmission gate function.
Referring to FIG. 2, the signals conveyed by the signal paths MA, MB and MC are multiplied by coefficients, stored in latches 218, 220 and 222, by the respective multipliers 212, 214 and 216. The output signals produced by the multipliers 212 and 214 are summed by an adder 224, the output signal of which is summed with the output signal of the multiplier 216 in the adder 226. The signal provided by the adder 226 is the output signal of the FIR filter.
In the present embodiment of the invention, the filter coefficient values are applied to the latches 218, 220 and 222 via the input signal path COEFF. A coefficient value for a particular column multiplier is applied to the latch input terminals at the same time that row address value for the column is applied to the row select circuitry 210. When the corresponding column select signal is strobed, the coefficient value is loaded into the latch at the same time that the switch state for the column is set. In an embodiment of the invention which uses a CTD for the delay elements, the latches 218, 220 and 222 would be sample-and-hold circuits and the signal path COEFF would provide analog coefficient values.
It is further contemplated that this invention may be practiced in the context of an input weighted sampled data filter. In an input weighted filter the individual delay elements are separated by signal summing circuitry. Input sample values are first weighted by the filter coefficient values and then applied to the input terminals of the summing circuits coupled to selected ones of the cascaded delay elements. At each of the selected delay elements, the weighted samples are summed with the values propogating through the preceding delay elements. The present invention would be realized in this context by placing the crossbar switch between the output terminals of the weighting circuits and the input terminals of the summing circuits between the cascaded delay elements.
A complex filter, either input weighted or output weighted, may be implemented using similar techniques. A complex filter built in accordance with the present invention would have two parallel chains of delay elements, one for the real signal and one for the imaginary signal. In an output-weighted filter, for example, each of the switch elements would couple the samples provided by corresponding stages of the two delay lines to real and imaginary output signal paths. The output signal paths would be connected to complex multipliers which would multiply the real and imaginary signals by real and imaginary coefficient values to produce real and imaginary output values. The real and imaginary signals provided by the complex multipliers would be summed separately to provide the real and imaginary components of the complex output signal.
|
A sampled data filter used in a television automatic ghost cancellation system employs a single chain of cascaded delay elements and a crossbar switch matrix to implement the several different delayed sequences of samples that are used by the system to cancel several ghost signals. The rows of switch elements in the crossbar switch matrix are coupled to the individual delay elements, and the columns of the matrix are coupled to sample scaling circuitry. The scaled samples are summed to develop a psuedo-ghost signal which is combined with the input signal to cancel the ghost signal components.
| 7
|
BACKGROUND OF THE INVENTION
This invention relates to a method of refining silicon tetrafluoride gas which contains oxygen-containing silicofluoride(s) such as fluorosiloxane and/or fluorosilanol as impurity matter.
High purity silicon tetrafluoride gas is useful for the preparation of amorphous silicon semiconductor which is expected as an advantageous material for various electronic devices including photovoltaic cell elements.
As is well known, silicon tetrafluoride gas readily reacts with water in liquid state to form hexafluorosilicic acid and gel-like silica as represented by the following equation (1). Furthermore, silicon tetrafluoride gas reacts with moisture in the atmosphere and even with a trace amount of water adsorbed on a metal or glass surface, or with the combined water in a clay-like mineral material such as zeolite or kaolin, to form hexafluorodisiloxane as represented by the following equation (2).
3SiF.sub.4 +2H.sub.2 O→2H.sub.2 SiF.sub.6 +SiO.sub.2 ( 1)
2SiF.sub.4 +H.sub.2 O→(SiF.sub.3).sub.2 O+2HF (2)
Therefore, it is almost inevitable that silicon tetrafluoride gas prepared by reaction between silica sand, silica gel or a silicate with hydrogen fluoride or hydrofluoric acid contains a certain amount of hexafluorodisiloxane as impurity matter. Besides, the result of mass spectrometry of silicon tetrafluoride gas often indicates the presence of trifluorosilanol SiF 3 OH too.
In the production of amorphous silicon by using silicon tetrafluoride gas by a glow discharge method for example, the presence of any oxygen-containing silicofluoride having either Si-SO bond or Si-O-Si bond in the silicon tetrafluoride gas is liable to result in the intrusion of Si-0-Si bond into the intended Si-Si network structure with detrimental influences on the properties of the obtained amorphous silicon as a semiconductor material.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an efficient and fully practicable method of refining silicon tetrafluoride gas containing at least one oxygencontaining silicofluoride as impurity, by which method the oxygen-containing silicofluoride(s) can almost completely be converted to slicon tetrafluoride.
Essentially a refining method according to the invention comprises the step of making a silicon tetrafluoride gas containing at least one oxygen-containing silicofluoride as impurity contact with hydrogen fluoride in the presence of a liquid medium which has strong affinity for water thereby forcing the oxygen-containing silicofluoride to react with hydrogen fluoride.
The fundamental concept of the present invention is to convert the oxygen-containing impurity in the silicon tetrafluoride gas to silicon tetrafluoride by forcing the impurity to react with hydrogen fluoride and, at the same time, suppressing the reaction between silicon tetrafluoride and water. The reaction intended in this refining method is represented by the following equation (3) where the oxygen-containing silicofluoride is hexafluorodisiloxane.
(SiF.sub.3).sub.2 O+2HF⃡2SiF.sub.4 +H.sub.2 O (3)
The reaction of Equation (3) is reversible, and the reverse reaction corresponds to the undesirable reaction of Equation (2). In order that the reaction of Equation (3) proceeds exclusively to the right, it is necessary to remove water formed by the reaction from the reaction system or to isolate the water from SiF 4 gas. In the refining method according to the invention, the liquid medium having strong affinity for water serves the purpose of efficiently absorbing water formed by the intended reaction. In the reaction system, therefore, the partial pressure of water in vapor phase remains at an extremely low level so that the undesirable reverse reaction hardly takes place. Owing to such effects of the strongly hydrophilic liquid medium in the refining method according to the invention, it has become possible to achieve refining of SiF 4 gas to such an extent that (SiF 3 ) 2 O or any other oxygen containing silicofluoride cannot be detected by infrared absorption spectrum analysis of the refined gas.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
There are a variety of liquid materials which have strong affinity for water and are useful as liquid medium in the method according to the invention. Preferred examples of suitable liquid materials are inorganic acids and some organic solvents such as glycerin and ethylene glycol. However, usually and particularly when it is required to obtain SiF 4 gas refined to utmost extent, it is more preferable to use an inorganic acid relatively low in volatility, such as sulfuric acid or phosphoric acid, than to use an organic solvent such as glycerin. Since the refining treatment according to the invention is usually carried out at a relatively low temperature, for example at ambient temperature, with the intention of rendering the partial pressure of water in vapor phase in the reaction system as low as possible, the use of an organic solvent as the liquid medium might result in insufficient contact between the SiF 4 gas to be purified and HF due to relatively high viscosity of the liquid medium. Both sulfuric acid and phosphoric acid are very strong in the affinity for water and low in volatility and, besides, are easy to industrially handle and available at low prices. For efficient absorption of water, it is suitable to use either sulfuric acid or phosphoric acid of sufficiently high concentration. In the case of sulfuric acid, for example, it is preferable that the concentration of H 2 SO 4 in the acid is at least 70% by weight firstly because the refining can be achieved highly effectively by doing so and secondly because the solubility of SiF 4 gas in such a concentrated sulfuric acid is sufficiently low.
In the refining method of the invention, the contact between the SiF 4 gas and HF in the presence of the liquid medium can be accomplished in various manners. For example, HF may be dissolved in the liquid medium in advance to perform the refining treatment by simply passing the SiF 4 gas through the liquid medium. Alternatively, the SiF 4 gas and HF gas may simultaneously be introduced into a plain liquid medium. It is also possible to perform counter-current contact between the SiF 4 gas and a liquid medium containing HF therein.
The quantity of HF required for achievement of the refining is variable depending on the content of the oxygen-containing silicofluoride in the SiF 4 gas to be refined. It suffices that the quantity of HF is slightly larger than a theoretical quantity according to Equation (3). The use of excessively large amount of HF is unfavorable because it will result in a considerable increase in the partial pressure of HF in the purifying apparatus and, hence, in the outflow of a considerable quantity of HF from the apparatus together with the refined SiF 4 gas, which places high load on the subsequent step of separating HF from the SiF 4 gas. When use is made of a liquid medium prepared by dissolving HF in sulfuric acid or phosphoric acid, usually it is suitable that the content of HF in the liquid medium is from about 0.1% to about 1.5% by weight. However, the content of HF in the liquid medium should adequately be increased if it is intended to purify a SiF 4 gas unusually high in the content of oxygen-containing silicofluoride(s). In the case of performing the refining operation by continuously passing SiF 4 gas through a liquid medium containing HF dissolved therein for long hours, there will arise the need of supplementing HF to the liquid medium at suitable intervals.
The reaction intended in the refining method of the invention smoothly proceeds at ambient temperature, but if desired it is permissible to somewhat heat or cool the reaction system or the liquid medium. In general relatively low temperatures are favorable for maintaining both the partial pressure of HF and the partial pressure of H 2 O in vapor phase at low levels, but relatively high temperatures are somewhat favorable for promoting the intended reaction. Considering the total effect and efficiency of the refining operation, it is suitable to employ a reaction temperature in the range from about 0° C. to ambient temperature.
The following examples further illustrate the present invention.
EXAMPLE 1
An experimentally prepared SiF 4 gas containing a certain amount of (SiF 3 ) 2 O was sampled and subjected to infrared spectrophotometry in a 100 mm long gas cell. (Gas cells of the same size were used throughout the examples.) In the infrared absorption spectrum of this gas, the logarithmic ratio of the absorption peak at 839 cm -1 attributed to the stretching vibration of SiF 3 of (SiF 3 ) 2 O to the absorption peak at 2057 cm -1 attributed to the stretching vibration of Si-F of SiF 4 was 0.121.
Several batchs of sulfuric acid different in H 2 SO 4 concentration were each forced to absorb a determined amount of anhydrous hydrogen fluoride to obtain several batchs of mixed acid of the compositions as shown in the following Table 1.
Three gas washing-bottles made of teflon employed as reaction vessels were connected in series with one another to constitute a purifying apparatus, and 130 g of mixed acid selected from the aforementioned batchs was put into every reaction vessel of the apparatus. In the first experiment the mixed acid in the apparatus was left at room temperature, and the aforementioned SiF 4 gas was continuously passed through the apparatus at a constant flow rate of 4 1/hr so as to make sufficient contact with the mixed acid. After the lapse of 1 hr, the gas under the purifying treatment was sampled at the outlet of the third-stage reaction vessel and subjected to infrared spectrophotometry. In this experiment four runs of the described process were carried out by using four different batchs of mixed acid. The results of this experiment are presented in Table 1.
In the second experiment, four runs of a generally similar process were carried out but by maintaining the mixed acid in the apparatus cooled at 0° C. in every run. Table 1 contains the results of the second experiment too.
TABLE 1______________________________________ Infrared Absorption Peak RatioComposition of Temper- (SiF.sub.3).sub.2 O/SiF.sub.4Mixed Acid (Wt %) ature before afterH.sub.2 SO.sub.4 HF H.sub.2 O (°C.) treatment treatment______________________________________96.0 1.3 2.7 20 0.121 0.00086.5 1.3 12.2 22 " 0.00077.2 1.3 21.5 18 " 0.00070.1 1.3 28.6 20 " 0.00196.0 1.3 2.7 0 " 0.00091.6 1.3 7.1 0 " 0.00081.6 1.3 17.1 0 " 0.00070.1 1.3 28.6 0 " 0.003______________________________________
The experimental results in Table 1 indicate that very efficient conversion of (SiF 3 ) 2 O to SiF 4 can be achieved when the concentration of H 2 SO 4 in the liquid medium is above about 70% by weight, and that an extremely good result can be obtained by making the liquid medium contain more than about 80% by weight of H 2 SO 4 . Also it is understood that almost similarly good results can be obtained whether the reaction is carried out at ambient temperature or at somewhat lower temperatures. As the third experiment to examine the effect of a variation in the content of HF in mixed acid used as the liquid medium, additional four runs were carried out generally in accordance with the above described second experiment but by using different mixed acids prepared by dissolving a variable amount of HF in sulfuric acid of a determined concentration. Table 2 shows the compositions of the mixed acids used in this experiment and the results of the experiment.
Table 2
TABLE 2______________________________________ Infrared Absorption Peak RatioComposition of Temper- (SiF.sub.3).sub.2 O/SiF.sub.4Mixed Acid (Wt %) ature before afterH.sub.2 SO.sub.4 HF H.sub.2 O (°C.) treatment treatment______________________________________96.0 1.3 2.7 0 0.121 0.00096.0 0.75 3.2 0 " 0.00196.0 0.48 3.5 0 " 0.01696.0 0.16 3.8 0 " 0.077______________________________________
As demonstrated by the results of this experiment, usually it suffices for achieving very efficient conversion of (SiF 3 ) 2 O to SiF 4 that a sulfuric acid base mixed acid as the liquid medium contains about 0.15 to about 1.0% by weight of HF.
EXAMPLE 2
A SiF 4 gas subjected to purification in this example was higher in the content of (SiF 3 ) 2 O than the SiF 4 gas used in Example 1. By infrared spectrophotometry, the logarithmic ratio of the absorption peak at 839 cm -1 characteristic of (SiF 3 ) 2 O to the absorption peak at 2057 cm -1 characteristic of SiF 4 was 0.236.
A mixed acid was prepared by forcing concentrated sulfuric acid to absorb anhydrous hydrogen fluoride such that the resultant mixed acid was composed of 96% of H 2 SO 4 , 0.48% of HF and 3.52% of water by weight.
Use was made of the apparatus described in Example 1, and 130 g of the mixed acid was put into each of the three washing-bottles employed as reaction vessels. The mixed acid in the apparatus was kept cooled at 10° C., and the SiF 4 gas was continuously passed through the apparatus at a constant flow rate of 4 1/hr so as to make sufficient contact with the mixed acid. After the lapse of 1 hr, the gas under the treatment was sampled at the outlet of each reaction vessel and subjected to infrared spectrophotometry.
In the infrared absorption spectrum of the gas sample taken at the outlet of the first-stage reaction vessel the logarithmic ratio of the absorption peak at 839 cm -1 to the absorption peak at 2057 cm -1 was 0.086, but the absorption peak ratio value lowered to 0.031 in the absorption spectrum of the gas sample taken at the outlet of the second-stage reaction vessel and to 0.006 in the absorption spectrum of the gas sample taken at the outlet of the third-stage reaction vessel.
EXAMPLE 3
The purifying process of Example 2 was repeated generally similarly, except that the mixed acid in the apparatus was left at room temperature (20° C.).
After the lapse of 1 hr from the start of the continuous treatment, the SiF 4 gas under the treatment was sampled and subjected to infrared absorption spectrum analysis. In the infrared absorption spectrum of the gas sample taken at the outlet of the first-stage reaction vessel the logarithmic ratio of the absorption peak at 839 cm -1 to the absorption peak at 2057 cm -1 was 0.059. However, no absorption peak was observed at 839 cm -1 in the absorption spectrums of the remaining gas samples respectively taken at the outlets of the second-stage and third-stage reaction vessels, so that the absorption peak ratio became 0.000 for these samples.
From a comparison between Example 2 and Example 3, it is understood that the efficiency of the purifying treatment becomes higher when the treatment temperature is at or about room temperature than in the cases of employing lower treatment temperatures.
EXAMPLE 4
A SiF 4 gas as the object of purification in this example was still higher in the content of (SiF 3 ) 2 O than the SiF 4 gas treated in Examples 2 and 3. By infrared absorption spectrum analysis, the logarithmic ratio of the absorption peak at 839 cm -1 to the absorption peak at 2057 cm -1 was 0.628.
A mixed acid was prepared by forcing concentrated sulfuric acid to absorb a relatively large amount of anhydrous hydrogen fluoride such that the resultant mixed acid was composed of 96% of H 2 SO 4 , 2.4% of HF and 1.6% of H 2 O by weight.
The SiF 4 gas was treated with this mixed acid by the same method and under the same conditions as in Example 3.
In the infrared absorption spectrum of the gas sample taken at the outlet of the first-stage reaction vessel the logarithmic ratio of the absorption peak at 839 cm -1 to the absorption peak at 2057 cm -1 was 0.075, and in the absorption spectrum of the gas sample taken at the outlet of the second-stage reaction vessel the absorption peak ratio was 0.006. However, no absorption peak was observed at 839 cm -1 in the absorption spectrum of the gas sample taken at the outlet of the thirdstage reaction vessel.
EXAMPLE 5
By infrared absorption spectrum analysis of a SiF 4 gas containing (SiF 3 ) 2 O as the object of purification in this example, it was found that the logarithmic ratio of the absorption peak at 839 cm -1 to the absorption peak at 2057 cm -1 was 0.357.
Employed as liquid medium was phosphoric acid in which the content of P 2 O 5 was 69.5%. The phosphoric acid was put into two reaction vessels that were connected to each other to constitute a two-stage purifying apparatus, and the phosphoric acid in the apparatus was left at room temperature. The SiF 4 gas was continuously introduced into the purifying apparatus at a constant flow rate of 4 1/hr, and simultaneously HF gas was introduced into the same apparatus at a constant flow rate of 50 ml/hr. The apparatus was arranged such that the introduced gases well dispersed in the phosphoric acid to form small bubbles.
By infrared absorption spectrum analysis of the gas sampled at the outlet of the second-stage reaction vessel, it was observed that the absorption peak at 1 839 cm -1 was almost negligible, so that the purifying treatment was judged to have achieved practically complete conversion of (SiF 3 ) 2 O contained in the starting gas to SiF 4 .
EXAMPLE 6
In the infrared absorption spectrum of a SiF 4 gas as the object of purification in this example, the logarithmic ratio of the absorption peak at 839 cm -1 to the absorption peak at 2057 cm -1 was 0.133.
Phosphoric acid containing 69.5% of P 2 O 5 was forced to absorb anhydrous hydrogen fluoride to obtain two kinds of mixed acids one of which contained 1.3% by weight of HF and the other 0.8% of HF. Additionally prepared by using phosphoric acid containing 59.3% of P 2 O 5 and anhydrous hydrogen fluoride were two kinds of mixed acids one of which contained 1.3% by weight of HF and the other 0.8% of HF.
By alternately using these four kinds of mixed acids, the SiF 4 gas was treated at a constant rate of 4 1/hr by using the method and apparatus described in Examples 1 and 2. For each mixed acid two runs of the purifying treatment were carried out by keeping the mixed acid in the apparatus at 0° C. in one run and at 18° C. (room temperature) in the other run. After the lapse of 1 hr from the start of each run, the gas was sampled at the outlet of the third-stage reaction vessel and subjected to infrared absorption spectrum analysis.
Table 3 shows the purifying conditions in this example and the results of the infrared absorption spectrum analysis.
TABLE 3______________________________________ Infrared AbsorptionComposition of Peak RatioMixed Acid (Wt %) Temper- (SiF.sub.3).sub.2 O/SiF.sub.4H.sub.3 PO.sub.4 ature before after(P.sub.2 O.sub.5) HF H.sub.2 O (°C.) treatment treatment______________________________________95.9 1.3 2.8 0 0.133 0.000(69.5) 18 " 0.00095.9 0.8 3.3 0 " 0.003(69.5) 18 " 0.00081.9 1.3 16.8 0 " 0.005(59.3) 18 " 0.00181.9 0.8 17.5 0 " 0.011(59.3) 18 " 0.006______________________________________
EXAMPLE 7
A fluorine-containing liquid medium was prepared by mixing 100 parts by weight of glycerin with 1.5 parts by weight of anhydrous hydrogen fluoride.
Use was made of the purifying apparatus described in Example 1, and 170 g of the fluorine-containing liquid medium was put into each reaction vessel of the apparatus. To lower the viscosity of the liquid medium in the reaction vessels, the purifying apparatus was placed in a constant-temperature tank in which the temperature was kept at 50°C. In this state, the SiF 4 gas mentioned in Example 6 was continuously passed through the purifying apparatus at a constant flow rate of 4 1/hr.
After the lapse of 1 hr from the start of the purifying treatment, the gas was sampled at the outlet of the third-stage reaction vessel and subjected to infrared absorption spectrum analysis. As the result the logarithmic ratio of the absorption peak at 839 cm -1 to the absorption peak at 2057 cm -1 was 0.077, and accordingly this purifying treatment was confirmed to be effective.
|
SiF 4 gas containing oxygen-containing silicofluoride(s) typified by (SiF 3 ) 2 O as impurity can be refined to extremely high purity by making the SiF 4 gas contact with HF in the presence of a liquid medium having strong affinity for water such as sulfuric acid or phosphoric acid. By reaction with HF, the impurity such as (SiF 3 ) 2 O is converted to SiF 4 , while the liquid medium absorbs water formed by the reaction to thereby prevent a reverse reaction between SiF 4 and H 2 O to form (SiF 3 ) 2 O.
| 2
|
BACKGROUND OF THE INVENTION
[0001] The invention relates to suspended ceiling systems and, in particular, to a novel clip for suspending a pair of main tees in parallel relation.
PRIOR ART
[0002] Certain ceiling treatments or designs utilize main tees in relatively closely spaced pairs to give a ceiling a distinctive appearance and/or to provide an intermediate space for lighting, HVAC systems, sprinkler systems and like services. It is known to use a series of special clips to support a pair of main tees in parallel relation. Such clips, typically, are suspended directly from overhead structure by steel wire. In certain geographic areas, local codes or requirements prohibit suspended ceilings from being suspended from overhead structure directly by plain wire ties. For example, in some areas, a C-channel must first be hung from the overhead structure and a suspended ceiling, fixtures and-like elements must be hung from these intermediate channels. As far as is known, there are no available clips or brackets that can be easily and quickly attached to the suspension channels that, in turn, can support a pair of main tees in a uniform parallel spacing.
SUMMARY OF THE INVENTION
[0003] The invention provides a clip that is compatible with overhead channel suspension and which supports a pair of grid main tees in precise parallel alignment. The clip of the invention is easy to use and thereby saves installation time and avoids fatigue on the part of the installer.
[0004] In its preferred form, the clip is arranged to work with prior art “drop clip” hangers compatible with the required overhead suspension channels. As disclosed, the clip is coupled to a hanger with simple manipulation of the hanger and clip elements without the need for the use of tools and/or separate fasteners. The compatibility of the disclosed clip with conventional drop clip C-channel hangers significantly reduces the cost and complexity of the tooling required to make the clip and, therefore, reduces the costs involved in making the clip. Additionally, the clip affords the known benefits of similar clips in producing a uniform spacing between the grid tee pairs which spacing is critical since variations are conspicuous to even the casual observer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a perspective fragmentary view of a pair of parallel grid tees supported by the clip of the invention from an overlying suspended structural channel;
[0006] FIG. 2 is a cross-sectional view of the spaced parallel grid tees and clip taken in the plane 2 - 2 indicated in FIG. 1 ;
[0007] FIG. 3 is an elevational view of the clip of the invention;
[0008] FIG. 4 is a side view of the clip;
[0009] FIG. 5 is a plan view of the clip;
[0010] FIG. 6 is a side elevational view of a known drop clip assembly; and
[0011] FIG. 7 is a side edge view of the known drop clip assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0012] A system 10 for suspending a pair of grid tees 11 in a uniformly spaced parallel arrangement is shown in FIG. 1 . The grid tees 11 , typically, are main tees with a generally conventional construction. Each of the tees 11 has lower flange portions 12 and a generally vertical web or stem 13 which includes, adjacent its upper edge, a reinforcing bulb 14 , as is customary. Typically, the grid tees are roll formed of sheet metal stock. The grid tees are suspended from a plurality of structural channels 16 . Only one channel 16 is illustrated in FIG. 1 , but it will be understood that a plurality of such channels 16 , typically, spaced parallel to one another, exist in a common plane spaced above the plane of the grid tees 11 . The channel 16 can be suspended in a building from the above floor or other superstructure existing above by means of suspension rods, wires, or the like.
[0013] FIGS. 6 and 7 illustrate a commercially available “drop clip” assembly 17 that includes a main body 18 and a locking channel or cap 19 . The main body 18 is a sheet metal stamping with a generally rectangular peripheral profile. A downwardly extending tab 20 works with the throat 21 to form a hook that captures the channel 16 . Adjacent its upper end, the body 18 has a rectangular throat 21 sized to provide a working clearance around the periphery of the structural channels 16 . Adjacent its lower end, the body 18 has a pair of parallel vertical slots 22 that leave three depending legs 23 - 25 . Outboard legs 23 , 25 are bent slightly below the plane of the drawing of FIG. 6 , while a central leg 24 is bent slightly above the plane of FIG. 6 . At their lower ends, the legs have channel shape formations 27 , 28 , that are configured to normally embrace the reinforcing bulb of a conventional grid tee. The locking channel cap 19 has a central slot in its web that enables it to slide vertically on the clip body 18 . When the locking channel cap 19 is manually forced downwardly over the legs 23 - 25 , including the channel formations 27 , 28 , the channel formations are forced towards the central plane of the upper portion of the body 18 ( FIG. 2 ). A lanced formation 29 on the central leg 24 serves to lock the locking channel cap 19 in position over the leg channel formations 27 , 28 . With the clip assembly 17 being manipulated onto a respective channel 16 so that it is received in the throat 21 , a section 31 of the body 18 can be bent upwardly to trap the clip assembly onto the channel.
[0014] A clip 36 of the invention serves to suspend the grid tees 11 from the drop clip body 18 and, therefore, from the structural channel 16 to which the drop clip assembly 17 is attached. The clip 36 , in the illustrated form, is a sheet metal stamping having the general form, when installed, of an inverted rectangular pan. The corners of the clip 36 are notched as required for receiving the bulbs 14 of the grid tees 11 . More particularly, the clip 36 has a generally planar, rectangular main section 37 from which depend downwardly bent opposed flanges 38 , 39 and 41 , 42 . The flanges 38 , 39 are mirror images of one another and each includes an inwardly bent tab 46 spaced vertically below the main section 37 a distance at least equal to and preferably slightly greater than the vertical height of the reinforcing bulb 14 of a grid tee. Another flange 41 , extending transversely between the imaginary planes of the flanges 38 , 39 , includes a pair of tabs 47 spaced from the plane of the main section 37 a distance equal to or slightly greater than the height of a reinforcing bulb 14 . The flanges 41 and 42 serve to stiffen the main section 37 of the clip 36 and keep it in a planar configuration under normally expected service conditions. The horizontal lengths of the flanges 41 , 42 are somewhat less than the inside dimension between the opposed flanges 38 , 39 so that, as shown in FIG. 2 , there is room, preferably with a slight clearance, for the grid tee bulbs 14 to be received between the surface of a flange 38 , 39 , and adjacent vertical end edge surfaces 51 , 52 on the flange 41 . The inside dimension spacing of the surfaces of the flanges 38 , 39 and the spacing between the vertical edge surfaces 51 , 52 , are determined by the desired center-to-center distance between the grid tees 11 and the width of the reinforcing bulbs 14 , typically the latter being nominally ¼″. As suggested in FIG. 2 , the upper edge surfaces 46 a, 47 a of the tabs 46 , 47 are spaced from the lower surface of the main section 37 a distance sufficient to receive the bulbs 14 of the grid tees. For illustrative purposes, end areas of the flange 41 and tabs 47 are shown in FIG. 2 , ignoring the fact that the plane of the section of FIG. 2 is technically behind these areas.
[0015] Disposed on opposite sides of an imaginary vertical mid-plane transverse to its length, the clip 36 has a pair of elongated transverse slots 53 . In the illustrated example, the slots 53 extend across substantially the full width of the clip main section 37 . The slots 53 are spaced from one another to leave a central land portion 54 that, preferably, has a width equal or substantially equal to the width of a conventional reinforcing bulb 14 , for example, nominally ¼″. The slots 53 are sufficiently wide and long to allow the free passage therethrough of the channel formations 27 , 28 of the drop clip legs 23 - 35 .
[0016] The clip 36 is joined and locked, i.e. coupled, to the drop clip assembly 17 in the following manner, conveniently at the job site by the grid installer without tools. The drop clip legs 23 - 25 , in their laterally spread condition shown in FIG. 7 , are inserted through the slots 53 so that in-turned flanges 57 , 58 of the channel formations 27 , 28 underlie the land 54 of the main clip section 37 . Thereafter, the locking channel cap 19 is forced downwardly relative to the drop clip body 18 so as to force the legs 23 , 25 towards the central leg 24 and vice versa thereby trapping the land 54 in the channel formations 27 , 28 above the flanges 57 , 58 . When the channel cap 19 fully contacts the channel formations 27 , 28 , it is locked in this position by the lance or lock 29 . As a consequence, the drop clip assembly 17 and paired tee clip are securely fixed together. Study of FIGS. 1 and 2 shows that the interconnection of the clips 17 and 36 is symmetrical about imaginary vertical planes, one at a mid-plane through the thickness of the main body 18 of the drop clip and another perpendicular to the plane of the main body midway between its vertical edges. This results in a symmetrical support of the paired tee clip 36 which, in turn, assures that each of the four tabs 46 , 47 of the clip 36 at their upper surfaces 46 a, 47 b are effective in supporting the vertical load on the respective grid tee bulbs 14 . It will be appreciated that the clip 36 in concert with identical clips spaced along the lengths of a pair of grid tees 11 can precisely horizontally space the pair of grid tees with minimal skill and effort expended on the part of the installer. The length of the clip 36 , i.e. its extent on each side of the plane of the drop clip main body 18 , can be adjusted to suit a particular installation as would ordinarily be determined by an architect, for example. The space between the parallel paired grid tees 11 can be utilized for lighting fixtures, HVAC air boots, sprinkler heads, speakers and other utilities and appliances.
[0017] It should be evident that this disclosure is by way of example and that various changes may be made by adding, modifying or eliminating details without departing from the fair scope of the teaching contained in this disclosure. The invention is therefore not limited to particular details of this disclosure except to the extent that the following claims are necessarily so limited.
|
A clip for accurately and quickly suspending pairs of spaced parallel grid main tees from superadjacent structural channels. The clip works with a separate drop clip that hooks over and depends from the structural channel. The paired main tee clip has a central body region configured like a conventional grid tee bulb thereby enabling the paired main tee clip to mate with the drop clip in the same way the drop clip mates with a conventional grid tee bulb thereby achieving a system that is cost-effective in manufacture and installation.
| 4
|
RELATED APPLICATION
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 09/399,654 filed on Sep. 21, 1999, which is pending.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method of manufacturing catamenial and tampon devices and, in particular, to a method which completely simplifies the conventional way of making an odor absorbent tampon.
[0004] 2. Description of the Prior Art
[0005] The assignee, as well as a number of other makers of catamenial or tampon devices, currently market such devices which achieve odor adsorbency in non-deodorant catamenials or tampons. However, such adsorbency is typically provided by a strip comprising an odor adsorbing material adhered to a non-woven material with an acrylic binder. The odor adsorbent strip is fed into the tampon forming machine along with rayon pads. The pads and strip are then formed into the tampon pledget. Alternately, the odor adsorbing material is mixed with water (a suspension aid, e.g., Veegum may be used) and added as a slurry directly to the rayon pads prior to their formation into the tampon pledget.
[0006] It will be manifest to those skilled in this art that the addition of the odor adsorbent strip, as described, is costly. A less costly alternative to the addition of a strip is to apply the odor adsorbent material, for example, as a powder or in a slurry, directly to the tampon. However, this and similar lower cost alternatives are technically more difficult since they involve additional steps in the tampon forming process and have the potential for leaving residue that would accumulate on the tampon forming equipment.
[0007] What has been discovered or recognized is that the technically difficult and problematic techniques, which are currently followed as possible alternatives for the addition of the odor adsorbent strip, can be avoided by adopting a more efficient method.
[0008] As background for an understanding and appreciation of the present invention, reference may be made to the following U.S. Pat. Nos. 3,222,857; 3,339,357; 3,479,811; and 5,460,881. Although these relate in general to processes and apparatus for producing impregnated fiber materials of one kind or another, they fail to recognize what is inherent in the concept of the present invention; that a significant advantage is obtained by uniquely combining with the usual steps involved in producing a catamenial/tampon device, the step, at the beginning of the process, of embedding the odor adsorbent material in the matrix fibers while these fibers are being formed or processed. In other words, prior to the actual formation or fabrication of the tampon pledget, the odor adsorbent material is placed or merged in the pledget's fibers.
[0009] A substantial benefit that results from the unique step described is that there is uniform distribution of the adsorbent within the finished catamenial/tampon product. This result contrasts sharply with that obtained by use of conventional processes.
SUMMARY OF THE INVENTION
[0010] It is an object of the present invention to simplify the process or method of making an odor adsorbent tampon.
[0011] It is another object of the present invention to provide such a process or method where one or more finely divided odor adsorbent materials, whether in particulate or liquid form, are incorporated directly into the fibers during the process of forming such fibers.
[0012] It is still another object of the present invention to provide such a process or method where the fibers having the one or more odor adsorbent materials are subsequently used to form a catamenial/tampon device.
[0013] It is a further object of the present invention to provide such a process or method where the one or more odor adsorbent materials is in liquid form.
[0014] It is still a further object of the present invention to provide such a process or method where the one or more odor adsorbent materials is naturally sourced.
[0015] The fundamental features of the present invention reside in a method of manufacturing a catamenial/tampon device and the product produced by that method. The method, briefly stated, includes the steps of forming a plurality of fibers, preferably by extrusion, and impregnating or urging into or inserting into the interstices of the fibers, one or more odor adsorbent materials while the process of forming the fibers is being performed. Thereafter, the plurality of fibers so formed are suitably and conventionally brought together to produce the finished device. Preferably, the one or more odor adsorbent materials is in liquid form and/or is naturally sourced.
[0016] Other and further objects, advantages and features of the present invention will be understood by reference to the following specification in conjunction with the annexed drawings, wherein like parts have been given like numbers.
BRIEF DESCRIPTION OF THE DRAWING
[0017] [0017]FIG. 1 is a perspective view of the apparatus deployed in the practice of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Referring to FIG. 1, there is provided a preferred arrangement for practicing the method of the present invention. Particularly, FIG. 1 illustrates the novel process by which fibers for use in tampons are impregnated with or have urged into or inserted into the interstices thereof one or more odor adsorbent materials, as the fibers are being generated. This method is different than having the pledget or the like formed from the fibers and impregnating the fibers with odor adsorbent material at a later stage of manufacturing.
[0019] Shown in FIG. 1 is an apparatus generally represented by reference numeral 10 by which the basic objective of the present invention is realized. Apparatus 10 has a tank or vessel 12 that contains a viscose solution 14 to which one or more odor adsorbent materials has been added. Viscose solution 14 is pumped by a conventional device 16 , such as an extrusion pump, connected to tank 12 and a second tank 22 to an emitting device 18 which is disposed in an acid bath 20 contained in tank 22 . Preferably, emitting device 18 has a plurality of apertures 24 .
[0020] Operation of extrusion pump 16 produces sufficient pressure to force viscose solution 14 or the like through apertures 24 and into acid bath 20 , thereby providing individual rayon fibers 26 that can be further conventionally processed to produce the catamenial product.
[0021] The one or more odor adsorbent materials may be any material that is capable of adsorbing odors. Such materials may essentially have no particulate matter, as in a liquid, or an amount of fine particulate matter, as in a zeolite, such that it can be incorporated into solution that forms the fiber. It is preferred that the one or more odor adsorbent materials be in liquid form and/or naturally sourced.
[0022] The one or more odor adsorbent materials that can be used in the process of the present invention may include, for example, one or more glycerins, glycerin compounds, aldehydes, natural oils, solutions of soluble natural compounds, natural plant and herb extracts, naturally occurring deodorizing actives, acids, bases, oxidants, chelating agents, esters, masking agents, sensory receptor alterants, oxidizing agents, biological agents, surfactants, surface active polymers, or any mixtures thereof.
[0023] Suitable glycerin compounds for use in the present invention include, for example, glycolic acid, glycerin stearate, glycerin monolaurate, glycerin monoalkyl ether, or any combinations thereof.
[0024] Aldehydes or aldehyde compositions containing an aldehyde selected from one class (Class A) and an aldehyde selected from a second class (Class B), have been found to have remarkable deodorant properties, clearly superior to those of each class of aldehyde compositions taken individually. The aldehyde technology consists of using materials of low vapor pressure. Efficacy is thought to be the result of a combination of various methods of neutralizing odors, which include, chemical reaction with malodorant molecules, slow evaporation of the functional ingredients, and a partial masking effect. In the presence of malodor, the reaction product has been chemically altered so that one of the following occurs: (1) the new molecule is more volatile and quickly evaporates, (2) the new molecule is much larger and virtually non-volatile so the nose cannot detect its presence, or (3) the new molecule, being chemically different, has a more pleasant odor profile.
[0025] Suitable Class A aldehydes, may include, for example, one or more acyclic aliphatic aldehydes, non-terpenic aliphatic aldehydes, non-terpenic alicyclic aldehydes, terpenic aldehydes, aliphatic aldehydes substituted by an aromatic group, bifunctional aldehydes, or any mixtures thereof. More specifically, suitable Class A aldehydes may include, for example, decanal, lilal, tripal, or any mixtures thereof.
[0026] Suitable Class B aldehydes may include, for example, one or more aldehydes having an unsaturation carried by the carbon in the alpha position of the aldehyde function, aldehydes having an unsaturation in the alpha position of the aldehyde function conjugated with an aromatic ring, aldehydes having the function carried by an aromatic ring, or any mixtures thereof. For example, the Class B aldehydes may include alpha-, betaunsaturated aldehydes including beta-aryl substituted alpha-, beta- unsaturated aldehydes, aromatic aldehydes, or any mixtures thereof. More specifically, suitable Class B aldehydes may include, for example, citral, benzaldehyde, vanillin, or any mixtures thereof.
[0027] The aldehyde compositions may contain three or more aldehydes, as long as each of the two classes are represented. Preferably, the aldehydes of Class A and Class B are present in a proportion of about 80/20 to about 20/80.
[0028] Natural oils may be used as a suitable odor absorbent material in the present invention. The natural oils can have the effect of suppressing the malodorant molecules and imparting a pleasant odor, which overpowers the malodor. By way of example, a suitable natural oil for use in the present invention is white cedar leaf oil.
[0029] Solutions of any soluble natural compounds capable of malodor counteraction may also be used in the present invention. One example of such a soluble natural compound is chlorophyll.
[0030] Natural plant and herb extracts may also be used as malodor counteractant materials in the present invention. By way of example, suitable natural extracts may include green tea extract, Glade® “Neutralizer” (proprietary mixture of plant and herb extracts), or any mixtures thereof.
[0031] Naturally occurring deodorizing active materials may also be used in the present invention to counteract malodors. Suitable naturally occurring deodorizing actives include, for example, farnesol, phenoxyethanol, alkali rhodanides, linalol, citronellol, geraniol, phenethyl alcohol, or any mixtures thereof.
[0032] One or more acids may be used as malodor counteractants that act to neutralize basic components of the malodor. Suitable acids include, for example, citric acid, acetic acid, other organic acids that are safe for use, or any mixtures thereof.
[0033] One or more bases may be used as malodor counteractants that act to neutralize acid components of the malodor. Suitable bases include, for example, ammonia, triethanolamine, or any mixtures thereof.
[0034] One or more oxidants that react with sulfide-containing compounds to reduce malodors may also be used in the present invention. By way of example, suitable oxidants may include ascorbic acid or other known oxidating materials.
[0035] One or more chelating agents that react with any metal components and reduce or eliminate malodors may be used in the present invention. Suitable chelating agents may include, for example, ascorbic acid or other known chelating agents, such as, for example, EDTA.
[0036] Certain esters having reactive double bonds have been found to have a quasi-universal ability of abating malodors. Suitable ester compounds for use in the present invention include, for example, NEUTROAIR® (a mixture of geranyl crotonate and dihexyl fumarate) or METAZENE® (lauryl methacrylate).
[0037] Masking agents may be used as a malodor counteractant material in the present invention. Any agent capable of masking malodor may be used. However, typically, for example, a perfume or fragrance is used to mask or hide the malodor.
[0038] Compounds that are capable of altering the body's sensory receptors may also be used in the present invention. Malodor counteractants share common areas of receptor sites with many known malodor-causing chemicals. Given sufficient concentration in the atmosphere, the malodor counteractants interact with the receptor proteins and render them unavailable to malodors. Therefore, without interaction of the malodor with the receptors, no perception of the malodor by the nose is possible. By way of example, Veilex® (proprietary ingredients), produced by BBA, is such a malodor counteractant suitable for use in the present invention.
[0039] One or more oxidizing agents may be used as malodor counteractants that act to oxidize components of the malodor. Any suitable oxidizing agent may be used in the absorbent article of the present invention that is safe for use, such as, for example, hydrogen peroxide.
[0040] One or more biological agents may be used as malodor counteractants in the absorbent article of the present invention. Suitable biological agents include, for example, bacterial spores, enzymes, or any mixtures thereof.
[0041] One or more surfactants may be used as malodor counteractants in the absorbent article of the present invention. Suitable surfactants include, for example, anionic, nonionic, cationic, zwitterionic, silicone, or any mixtures thereof.
[0042] One or more surface-active polymers may be used as malodor counteractants in the absorbent article of the present invention. Suitable surface-active polymers include, for example, acrylate polymers.
[0043] From the description herewith provided of the present invention, it will be understood that the great advantage and benefit of incorporating the odor adsorbent material in the first instance directly into the fibers eliminates both the potential for dusting during processing of catamenial devices and the need for binders and/or thickening agents that are normally used in the conventional methods. As previously noted, the method has been made more effective because the impregnation step normally performed at the end stage of the manufacturing procedures has already been accomplished, thereby eliminating the residue accumulation problem previously discussed.
[0044] The final step in the method of the present invention is a conventional step of bringing together a plurality of the individual fibers 26 formed and treated as described, so as to produce the finished product. Thus the already impregnated fibers, whether they be of rayon or other materials, are brought together as rayon and/or cotton fiber have conventionally been brought together in known tampons and in other catamenial devices. This bringing together can be accomplished by conventional non-weaving techniques.
[0045] Although in this description of the present invention a preferred embodiment thereof is specifically illustrated, it will be appreciated that alternate techniques may be exploited for achieving the essential objective of incorporating the odor adsorbent material in the fibers while such fibers are being formed or processed.
[0046] The present invention having been thus described with particular reference to the preferred forms thereof, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
|
The present invention provides a method for making an odor adsorbent tampon or related catamenial device. The method of the present invention includes the steps of forming a plurality of fibers, preferably by extrusion, and impregnating or urging into or inserting into the interstices of the fibers with one or more odor adsorbent materials while the process of forming the fibers is being performed. Thereafter, the plurality of fibers so formed are suitably and conventionally brought together to produce the finished device. Preferably, the one or more odor adsorbent materials is in liquid form and/or is naturally sourced.
| 3
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims priority to Chinese Patent Application No. CN201610294588.5, filed on May 5, 2016, the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to a phase-shift converter based on zero-voltage switching and zero-current switching technologies, in particular to a soft-switching bidirectional phase-shift converter which is applicable to a system for quickly charging an electric vehicle in various occasions and which can realize a linear control of an output voltage and has a wider output load range.
BACKGROUND
[0003] At present, the electric vehicle industry is developing rapidly and has a promising prospect, and related fast charging technologies are indispensable. It is crucial to develop high-performance vehicle fast-charging piles. Among various types of DC-DC converters, phase-shift converters are widely used as the basic topological structures of the chargers for electric vehicles, due to their advantages of low loss, high power density, fixed switching frequency, easy control, etc. However, due to its own limitations, the phase-shift converter topology has low output efficiency in the light load case, which influences the stability of the converter, and has no capability of linear control of output voltage.
[0004] Chinese Patent CN104333229A discloses a phase-shift full-bridge switch converter. A phase-shift full-bridge switch converter capable of improving the reliability of a power semiconductor switch device is provided in view of the defects in the prior art wherein a resonant transformer circuit and a resonant transformer controller are additionally provided between a leading bridge arm and its isolated driving circuit, and a high-frequency transformer, and an output current sampling circuit are additionally provided between the output ground terminal of an output filter circuit and a phase-shift control circuit.
[0005] However, in the researches on phase-shift converters currently done in the social and academic circles, including the above invention, the problem that the efficiency of a phase-shift converter becomes lower in light-load cases has not yet been solved, and the linear control of output voltage cannot be realized.
SUMMARY OF THE INVENTION
[0006] In view of this, a main objective of the present invention is to provide a soft-switching bidirectional phase-shift converter which can realize a linear control of output voltage and has a wider output load range. By changing the control mode of each switching transistor, the phase-shift converter is applicable to the light-load case, without influencing the operation in heavy-load case.
[0007] To achieve this objective, the present invention discloses a soft-switching bidirectional phase-shift converter with an extended load range, including an inverter bridge, a rectifier bridge, a transformer connected between the output side of the inverter bridge and the input side of the rectifier bridge, and an equivalent inductor representing the leakage inductance of a primary side of the transformer, wherein a DC input voltage is applied to the input side of the inverter bridge, and an output load is connected to the output side of the rectifier bridge.
[0008] The inverter bridge includes a leading bridge arm for realizing zero-current switching, and a lagging bridge arm for realizing zero-voltage switching.
[0009] The leading bridge arm includes: an inverter-side MOSFET switching transistor Q 1 and an antiparallel diode D 1 and a stray capacitor C 1 respectively corresponding to the inverter-side MOSFET switching transistor Q 1 , which are all connected in parallel, and an inverter-side MOSFET switching transistor Q 2 , and an antiparallel diode D 2 and a stray capacitor C 2 respectively corresponding to the inverter-side MOSFET switching transistor Q 2 , which are all connected in parallel; and, the lagging bridge arm includes an inverter-side MOSFET switching transistor Q 3 and an antiparallel diode D 3 and a stray capacitor C 3 respectively corresponding to the inverter-side MOSFET switching transistor Q 3 which are all connected in parallel, and an inverter-side MOSFET switching transistor Q 4 and an antiparallel diode D 4 and a stray capacitor C 4 respectively corresponding to the inverter-side MOSFET switching transistor Q 4 which are all connected in parallel.
[0010] The drain of the inverter-side MOSFET switching transistor Q 1 is connected to the anode of the antiparallel diode D 1 and one terminal of the stray capacitor C 1 , while the source thereof is connected to the cathode of the antiparallel diode D 1 and the other terminal of the stray capacitor C 1 ; the drain of the inverter-side MOSFET switching transistor Q 2 is connected to the anode of the antiparallel diode D 2 and one terminal of the stray capacitor C 2 , while the source thereof is connected to the cathode of the antiparallel diode D 2 and the other terminal of the stray capacitor C 2 ; the drain of the inverter-side MOSFET switching transistor Q 1 is connected to the source of the inverter-side MOSFET switching transistor Q 2 .
[0011] The drain of the inverter-side MOSFET switching transistor Q 3 is connected to the anode of the antiparallel diode D 3 and one terminal of the stray capacitor C 3 , while the source thereof is connected to the cathode of the antiparallel diode D 3 and the other terminal of the stray capacitor C 3 ; the drain of the inverter-side MOSFET switching transistor Q 4 is connected to the anode of the antiparallel diode D 4 and one terminal of the stray capacitor C 4 , while the source thereof is connected to the cathode of the antiparallel diode D 4 and the other terminal of the stray capacitor C 4 ; and, the drain of the inverter-side MOSFET switching transistor Q 3 is connected to the source of the inverter-side MOSFET switching transistor Q 4 .
[0012] The anode of the DC input voltage is connected to the sources of the inverter-side MOSFET switching transistors Q 1 and Q 3 , while the cathode thereof is connected to the drains of the inverter-side MOSFET switching transistors Q 2 and Q 4 .
[0013] The inverter bridge further includes an input filter capacitor which is located on the input side of the inverter bridge and connected to the DC input voltage in parallel; and, the anode of the DC input voltage is connected to the anode of the input filter capacitor, while the cathode thereof is connected to the cathode of the input filter capacitor.
[0014] The rectifier bridge includes: a rectifier-side MOSFET switching transistor M 1 , and an antiparallel diode Dm 1 and a stray capacitor Cm 1 respectively corresponding to the rectifier-side MOSFET switching transistor M 1 , which are all connected in parallel; a rectifier-side MOSFET switching transistor M 2 , and an antiparallel diode Dm 2 and a stray capacitor Cm 2 respectively corresponding to the rectifier-side MOSFET switching transistor M 2 , which are all connected in parallel; a rectifier-side MOSFET switching transistor M 3 , and an antiparallel diode Dm 3 and a stray capacitor Cm 3 respectively corresponding to the rectifier-side MOSFET switching transistor M 3 , which are all connected in parallel; and a rectifier-side MOSFET switching transistor M 4 , and an antiparallel diode Dm 4 and a stray capacitor Cm 4 respectively corresponding to the rectifier-side MOSFET switching transistor M 4 , which are all connected in parallel.
[0015] One terminal of the equivalent inductor is connected to the drain of the inverter-side MOSFET switching transistor Q 1 of the leading bridge arm while the other terminal thereof is connected to one terminal of the primary side of the transformer, and the other terminal of the primary side of the transformer is connected to the drain of the inverter-side MOSFET switching transistor Q 3 of the lagging bridge arm; a secondary-side dotted-terminal of a terminal of the transformer connected to the primary-side equivalent inductor is connected to the drain of the rectifier-side MOSFET switching transistor M 1 , and connected to the source of the rectifier-side MOSFET switching transistor M 2 , the anode of the antiparallel diode Dm 1 , the cathode of the antiparallel diode Dm 2 , one terminal of the stray capacitor Cm 1 and one terminal of the stray capacitor Cm 2 ; a secondary-side dotted-terminal of a terminal of the transformer not connected to the primary-side equivalent inductor is connected to the drain of the rectifier-side MOSFET switching transistor M 3 , and connected to the source of the rectifier-side MOSFET switching transistor M 4 , the anode of the antiparallel diode Dm 3 , the cathode of the antiparallel diode Dm 4 , one terminal of the stray capacitor Cm 3 and one terminal of the stray capacitor Cm 4 ; the cathode of the antiparallel diode Dm 1 is connected to the cathode of the antiparallel diode Dm 3 , and connected to the cathode of the output load, the other terminal of the stray capacitor Cm 1 and the other terminal of the stray capacitor Cm 3 ; and, the anode of the antiparallel diode Dm 2 is connected to the anode of the antiparallel diode Dm 4 , and connected to the cathode of the output load, the other terminal of the stray capacitor Cm 2 and the other terminal of the stray capacitor Cm 4 .
[0016] The rectifier further includes an output filter capacitor located on the output side; the cathode of the antiparallel diode Dm 1 and the cathode of the antiparallel diode Dm 3 are connected to the anode of the output filter capacitor, and the anode of the output filter capacitor is connected to the anode of the output load; and, the anode of the antiparallel diode Dm 2 and the anode of the antiparallel diode Dm 4 are connected to the cathode of the output filter capacitor, and the cathode of the output filter capacitor is connected to the cathode of the output load.
[0017] For the phase-shift converter system for quickly charging an electric vehicle based on zero-voltage switching and zero-current switching in the present invention, by optimizing on basis of a typical topology and changing the control mode of each switching transistor, the phase-shift converter is applicable to light-load cases, without influencing the operation in heavy-load cases, so the available load range of the present charger is extended. Under the optimal control and topological conditions, the present invention can realize the linear control of output voltage of the phase-shift converter, so that it is more advantageous for the control of output characteristics of the charger.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a schematic diagram of a topological structure of a phase-shift converter based on the zero-voltage and zero-current switching technology according to the present invention;
[0019] FIG. 2 is a schematic diagram of control of switching ransistors in the circuit according to the present invention;
[0020] FIG. 3 is an equivalent circuit diagram of a power transfer stage according to the present invention;
[0021] FIG. 4 is a schematic diagram of DC characteristics of an improved phase-shift converter according to the present invention;
[0022] FIG. 5 is a comparison diagram of an improved output linear voltage control and a conventional output non-linear voltage control according to the present invention;
[0023] FIG. 6 is a schematic diagram of the maximum load current under the boundary zero-current switching according to the present invention;
[0024] FIG. 7 is an equivalent circuit diagram of a freewheeling stage according to the present invention;
[0025] FIG. 8 is a schematic diagram of an extended output load range according to the present invention; and
[0026] FIG. 9 is a comparison diagram of power conversion efficiency of full load range according to the present invention.
[0027] FIG. 10 is a comparison diagram of power conversion efficiency in light load case according to the present invention.
[0028] FIG. 11 is a diagram of transformer primary voltage and current of the present invention at an output power of 115 W.
[0029] FIG. 12 is a diagram of drain-source voltage, drain current and gate voltage of transistor Q 2 which shows its switching under zero current condition.
[0030] FIG. 13 is a diagram of drain-source voltage, drain current and gate voltage of transistor Q 4 which shows its switching under zero voltage condition.
DETAILED DESCRIPTION OF THE INVENTION
[0031] To further understand the structure and implementation effects of the present invention, details will be described hereinafter by preferred embodiments with reference to the accompanying drawings.
[0032] FIG. 1 is a schematic diagram of a topological structure of a phase-shift converter based on the zero-voltage and zero-current switching technology according to the present invention, which is a core component of an electric vehicle charger. As shown in FIG. 1 , the topological structure provided by the present invention is based on a conventional DC-DC phase-shift converter, but on the output diode rectifier bridge side, control is changed to be performed by a switching transistor having a reverse diode. The bidirectional phase-shift converter provided by the present invention includes an inverter bridge, a rectifier bridge, a transformer T connected between the output side of the inverter bridge and the input side of the rectifier bridge, and an equivalent inductor L lk (not shown) representing the linkage inductance of a primary side of the transformer T. The ratio of transformation of the transformer T is N1:N2. A DC input voltage V in is applied to the input side of the inverter bridge, and an output load R L is connected to the output side of the rectifier bridge.
[0033] The inverter bridge includes a leading bridge arm (i.e., left arm) for realizing zero-current switching and a lagging bridge arm (i.e., right arm) for realizing zero-voltage switching. The inverter bridge may further include an input filter capacitor C in which is located on the input side and connected to the DC input voltage V in in parallel.
[0034] The leading bridge arm includes: an inverter-side MOSFET switching transistor Q 1 , and an antiparallel diode D 1 and a stray capacitor C 1 respectively corresponding to the inverter-side MOSFET switching transistor Q 1 , which are all connected in parallel, and an inverter-side MOSFET switching transistor Q 2 , and an antiparallel diode D 2 and a stray capacitor C 2 respectively corresponding to the inverter-side MOSFET switching transistor Q 2 , which are all connected in parallel. The drain of the inverter-side MOSFET switching transistor Q 1 is connected to the anode of the antiparallel diode D 1 and one terminal of the stray capacitor C 1 , while the source thereof is connected to the cathode of the antiparallel diode D 1 and the other terminal of the stray capacitor C 1 . The drain of the inverter-side MOSFET switching transistor Q 2 is connected to the anode of the antiparallel diode D 2 and one terminal of the stray capacitor C 2 , while the source thereof is connected to the cathode of the antiparallel diode D 2 and the other terminal of the stray capacitor C 2 . The drain of the inverter-side MOSFET switching transistor Q 1 is connected to the source of the inverter-side MOSFET switching transistor Q 2 . The lagging bridge arm includes: an inverter-side MOSFET switching transistor Q 3 and an antiparallel diode D 3 and a stray capacitor C 3 respectively corresponding to the inverter-side MOSFET switching transistor Q 3 which are all connected in parallel, and an inverter-side MOSFET switching transistor Q 4 and an antiparallel diode D 4 and a stray capacitor C 4 respectively corresponding to the inverter-side MOSFET switching transistor Q 4 which are all connected in parallel. The drain of the inverter-side MOSFET switching transistor Q 3 is connected to the anode of the antiparallel diode D 3 and one terminal of the stray capacitor C 3 , while the source thereof is connected to the cathode of the antiparallel diode D 3 and the other terminal of the stray capacitor C 3 . The drain of the inverter-side MOSFET switching transistor Q 4 is connected to the anode of the antiparallel diode D 4 and one terminal of the stray capacitor C 4 , while the source thereof is connected to the cathode of the antiparallel diode D 4 and the other terminal of the stray capacitor C 4 , The drain of the inverter-side MOSFET switching transistor Q 3 is connected to the source of the inverter-side MOSFET switching transistor Q 4 .
[0035] The anode of the DC input voltage V in is connected to the anode of the input filter capacitor C in and also connected to the sources of the inverter-side MOSFET switching transistors Q 1 and Q 3 , while the cathode thereof is connected to the cathode of the input filter capacitor C in and also connected to the drains of the inverter-side MOSFET switching transistors Q 2 and Q 4 .
[0036] The rectifier bridge in the present invention includes: a rectifier-side MOSFET switching transistor M 1 , and an antiparallel diode Dm 1 and a stray capacitor Cm 1 respectively corresponding to the rectifier-side MOSFET switching transistor M 1 , which are all connected in parallel; a rectifier-side MOSFET switching transistor M 2 , and an antiparallel diode Dm 2 and a stray capacitor Cm 2 respectively corresponding to the rectifier-side MOSFET switching transistor M 2 , which are all connected in parallel; a rectifier-side MOSFET switching transistor M 3 , and an antiparallel diode Dm 3 and a stray capacitor Cm 3 respectively corresponding to the rectifier-side MOSFET switching transistor M 3 , which are all connected in parallel; and a rectifier-side MOSFET switching transistor M 4 , and an antiparallel diode Dm 4 and a stray capacitor Cm 4 respectively corresponding to the rectifier-side MOSFET switching transistor M 4 , which are all connected in parallel. The rectifier may further include an output filter capacitor C out which is located on the output side and connected to the output load R L in parallel.
[0037] One terminal of the equivalent inductor L lk is connected to the drain of the inverter-side MOSFET switching transistor Q 1 of the left arm while the other terminal thereof is connected to one terminal of the primary side of the transformer T, and the other terminal of the primary side of the transformer T is connected to the drain of the inverter-side MOSFET switching transistor Q 3 of the right arm. A secondary-side dotted-terminal of a terminal of the transformer T connected to the primary-side equivalent inductor L lk is connected to the drain of the rectifier-side MOSFET switching transistor M 1 and connected to the source of the rectifier-side MOSFET switching transistor M 2 , the anode of the antiparallel diode Dm 1 , the cathode of the antiparallel diode Dm 2 , one terminal of the stray capacitor Cm 1 and one terminal of the stray capacitor Cm 2 . A secondary-side dotted-terminal of a terminal of the transformer T not connected to the primary-side equivalent inductor L lk is connected to the drain of the rectifier-side MOSFET switching transistor M 3 , and connected to the source of the rectifier-side MOSFET switching transistor M 4 , the anode of the antiparallel diode Dm 3 , the cathode of the antiparallel diode Dm 4 , one terminal of the stray capacitor Cm 3 and one terminal of the stray capacitor Cm 4 . The cathode of the antiparallel diode Dm 1 is connected to the cathode of the antiparallel diode Dm 3 , and connected to the anode of the output filter capacitor C out , the cathode of the output load R L , the other terminal of the stray capacitor Cm 1 and the other terminal of the stray capacitor Cm 3 . The anode of the antiparallel diode Dm 2 is connected to the anode of the antiparallel diode Dm 4 , and connected to the cathode of the output filter capacitor C out , the cathode of the output load R L , the other terminal of the stray capacitor Cm 2 and the other terminal of the stray capacitor Cm 4 .
[0038] FIG. 2 is a schematic diagram of control of the switching transistors in the circuit according to the present invention, where V GS1 to V GS4 represent driving signals of the inverter-side MOSFET switching transistors Q 1 to Q 4 , respectively, and V M1 to V M4 represent driving signals of the rectifier-side MOSFET switching transistors M 1 to M 4 , respectively. In heavy-load cases, the operation of the phase-shift converter is the same as that of a conventional phase-shift converter. However, in light-load cases, as shown in FIG. 2 , there are six stages in a positive half cycle.
[0039] In a stage of t 0 <t<t 1 , all the switching transistors M 1 to M 4 of the rectifier bridge have been turned off. On the inverter bridge side, the MOSFET switching transistor Q 4 is turned on, and the MOSFET switching transistor Q 2 is turned off at zero current since the primary-side current of the transformer T is zero. The main significance of this stage is to avoid the shoot-through short circuit between the MOSFET switching transistors Q 1 and Q 2 . In a state of t 1 <t<t 2 , the MOSFET switching transistors Q 1 , M 1 and M 4 are turned on at zero current, the DC input voltage V in is applied to the primary side of the transformer T, and the secondary-side voltage of the transformer T is maintained at the output voltage V out by the output filer capacitor C out . This stage is called a “left-arm zero-current conversion stage”. In a state of t 2 <t<t 3 , the MOSFET switching transistors Q 1 Q 4 , M 1 and M 4 are maintained in the ON state. This stage is a main power transfer stage. In a state of t 3 <t<t 4 , the MOSFET switching transistor Q 1 is maintained in the ON state, the MOSFET switching, transistor Q 4 is turned off, the energy stored in the equivalent inductor L lk starts to charge the stray capacitor C 4 and meanwhile discharge the C 3 , and the antiparallel diode D 3 is continuously turned on until the voltage of the stray capacitor C 3 becomes zero. Hereafter, the MOSFET switching transistor Q 3 is turned on at zero voltage, and the MOSFET switching transistors M 1 and M 4 are turned off at this stage. This stage is called a “right-arm zero-voltage conversion stage”. In a state of t 4 <t<t 5 , the MOSFET switching transistors Q 1 and Q 3 are continuously turned on, the primary-side voltage of the transformer T is zero, the energy stored in the equivalent inductor L lk is continuously transferred to the rectifier bridge side through the antiparallel diodes Dm 1 and Dm 4 and then transferred to the load, and the secondary-side voltage of the transformer T is continuously maintained at V out . This stage is called a “freewheeling stage”. In a state of t 5 <t<t 6 , the MOSFET switching transistors Q 1 and Q 3 are maintained in the ON state, the primary-side current of the transformer T is reduced to zero, and the antiparallel diodes Dm 1 and Dm 2 are biased reversely, so the network consisting of the output filter capacitor C out and the output load R L is isolated from the rectifier bridge. As the output filter capacitor C out is large enough, the output voltage V out may remain almost unchanged.
[0040] As shown in FIG. 2 , the working principle and mode in the negative half cycle in the light-load case is completely the same as that in the positive half cycle.
[0041] FIG. 3 is an equivalent circuit diagram of the power transfer stage according to the present invention. At this stage, energy is transferred from the output-side voltage to the load. i on (t) represents the primary-side current of the transformer at the power transfer stage, i off (t) represents the primary-side current of the transformer at the freewheeling stage, v c (t) represents the voltage of an equivalent output filter capacitor, i c (t) represents the current of the equivalent output filter capacitor, and i r (t) represents the current of an equivalent output load. The equivalent formulae of the circuits are as follows:
[0000]
L
lk
d
dt
i
on
(
t
)
=
V
in
-
n
·
v
c
(
t
)
(
1
)
i
on
(
t
)
=
i
r
(
t
)
n
+
i
c
(
t
)
n
(
2
)
n
·
v
c
(
t
)
=
i
r
(
t
)
n
·
n
2
·
R
L
(
3
)
i
c
(
t
)
n
=
C
out
n
2
·
d
dt
[
n
·
v
c
(
t
)
]
(
4
)
[0042] The equations (1) to (4) are solved and then Laplace transform performed, so as to obtain the primary-side current i on (s):
[0000]
I
on
(
s
)
=
s
L
lk
+
1
C
out
L
lk
R
L
s
2
+
s
C
out
L
lk
+
n
2
C
out
L
lk
R
L
V
in
s
1
L
lk
s
2
+
s
C
out
L
lk
+
n
2
C
out
L
lk
R
L
nV
out
(
5
)
[0043] wherein s=jω, ω=2πƒ, and
[0000]
f
=
1
t
.
[0044] Therefore, inverse Laplace transform may be performed on equation (5) to obtain i on (t):
[0000]
i
on
(
t
)
=
V
in
n
2
R
L
-
V
in
n
2
R
L
e
t
2
C
out
R
L
cos
(
θ
·
t
)
+
(
2
n
2
C
out
R
L
2
(
V
in
-
nV
out
)
-
L
lk
V
in
n
2
R
L
4
n
2
C
out
L
lk
R
L
2
-
L
lk
2
)
e
t
2
C
out
R
L
sin
(
θ
·
t
)
(
6
)
[0045] Wherein
[0000]
θ
=
4
n
2
C
out
L
lk
R
L
2
-
L
lk
2
2
C
out
L
lk
R
L
.
[0046] If it is assumed that the output filter capacitor C out is large enough and the leakage inductance L lk is small, the following in equations may be obtained:
[0000] 4n 2 C out L lk R L 2 >>L lk 2
[0000] 2n 2 C out R L 2 V in >>L lk V in
[0000] 2C out R L <<1.
[0047] Thus, the equation (6) may be simplified as follows (wherein ω s represents the switching angular frequency, ω 0 represents the output resonance frequency, and
[0000]
ω
o
=
n
L
lk
C
out
)
:
[0000]
i
on
(
t
)
≈
V
in
-
nV
out
Z
o
sin
(
ω
o
t
)
.
[0048] At the end of this stage (t=DT/2, wherein D represents the phase-shift duty ratio and T represents the period), a peak value of the primary-side current is as follows:
[0000]
I
peak
≈
D
π
ω
o
ω
s
V
in
-
nV
out
Z
o
(
7
)
[0000] wherein Z 0 represents the characteristic impedance, and
[0000]
Z
o
=
n
L
lk
C
out
.
[0049] If it is assumed that the input energy W in is equal to the output energy W out ,
[0000]
W
in
=
1
2
V
in
I
peak
D
T
2
,
W
out
=
V
out
2
R
L
T
2
,
[0000] then:
[0000]
I
peak
=
2
V
out
2
DR
L
V
in
(
8
)
[0050] The equations (7) and (8) are solved to obtain the ratio of transformation of the voltage input and voltage output of the phase-shift converter (wherein ƒ s represents the switching angular frequency, and
[0000]
f
s
=
ω
s
2
π
)
:
[0000]
V
out
V
in
=
1
2
[
(
nR
L
D
2
4
L
lk
f
s
)
2
+
4
(
R
L
D
2
4
L
lk
f
s
)
-
(
nR
L
D
2
4
L
lk
f
s
)
]
(
9
)
[0051] To check whether there is a linear relation between the output voltage and the phase-shift duty ratio D, a differential operation is performed on the equation (9) with respect to D:
[0000]
d
dD
(
V
out
V
in
)
=
D
2
n
2
R
L
+
8
L
lk
f
s
-
D
2
n
2
R
L
(
16
L
lk
f
s
+
D
2
n
2
R
L
)
4
L
lk
f
s
DnR
L
D
2
n
2
R
L
(
16
L
lk
f
s
+
D
2
n
2
R
L
)
(
10
)
[0052] As the denominator on the right side of the equation (10) is constantly greater than zero, it is only necessary to verify whether the value of the numerator is positive or negative. The value of the numerator is assigned to M:
[0000] M=D 2 n 2 R L +8 L lk ƒ s −√{square root over ( D 2 n 2 R L (16 L lk ƒ s D 2 n 2 R L ))} (11).
[0053] If M<0, then:
[0000] D 2 n 2 R L +8 L lk ƒ s −√{square root over ( D 2 n 2 R L (16 L lk ƒ s D 2 n 2 R L ))} (8 L lk ƒ s ) 2 >0.
[0054] As (8L lk ƒ s ) 2 is constantly greater than zero, both M and
[0000]
d
dD
(
V
out
V
in
)
[0000] are constantly greater than zero when 0≦D≦1. Therefore, the output voltage of the converter always increases with the increase of the phase-shift duty ratio D.
[0055] FIG. 4 is a schematic diagram of DC characteristics of an improved phase-shift converter according to the present invention, and FIG. 5 is a comparison diagram of an improved bidirectional phase-shift DC-DC converter (linear voltage control) and a typical directional phase-shift DC-DC converter (nonlinear voltage control) according to the present invention. The correctness of the mathematical calculations is verified by testing and simulating platforms.
[0056] FIG. 6 is a schematic diagram of the maximum load current under the boundary zero-current switching according to the present invention, showing four typical primary-side current cases. In (a) of FIG. 6 , the converter drives a light load in a left-arm zero-current switching mode. When the load is gradually increased to a boundary value, as shown in (b) of FIG. 6 , the zero-current switching may still be maintained. However, if the load exceeds the boundary value, the switching transistor whose left arm is in the ON state cannot operate in a zero-current switching mode, as shown in (c) of FIG. 6 . Of course, if the load is high enough, the converter will operate in a normal heavy-load mode, as shown in (d) of FIG. 6 .
[0057] FIG. 7 is an equivalent circuit diagram of the freewheeling stage according to the present invention. Based on the circuit diagram, by mathematical calculations, the maximum load current that can be withstood by the left arm while realizing zero-current switching is:
[0000]
I
ZCS
(
max
)
=
V
in
(
n
2
R
L
-
4
L
lk
f
s
)
n
3
R
L
2
(
12
)
[0058] The minimum load current that can be withstood by the right arm while realizing zero-voltage switching is:
[0000]
I
ZVS
(
min
)
=
2
V
in
nR
L
V
in
+
nR
L
V
in
+
4
R
L
C
sum
f
s
(
V
in
-
nV
out
)
2
(
13
)
[0000] wherein C sum C 3 +C 4 C xƒmr , C xƒmr represents the equivalent capacitance of the transformer T.
[0059] FIG. 8 is a schematic diagram of an extended output load range according to the present invention, and also shows the boundary value of the load current in equations (12) and (13). The conventional phase-shift converter is merely applicable to the heavy-load mode. In contrast, by the zero-current and zero-voltage switching design of the left and right arms, the phase-shift converter of the present invention realizes the stable operation in the light-load case, so that the output load range, including light load and heavy load, of the phase-shift converter is extended.
[0060] FIG. 9 is a comparison diagram of the power conversion efficiency of full load range according to the present invention, and FIG. 10 is a comparison diagram of the power conversion efficiency at light load case according to the present invention. The experimental data indicates that the conventional phase-shift transformer has low efficiency in light-load cases. As shown in FIG. 10 , the efficiency at a load of 115 W is about 76.5% only. However, in the present invention, the efficiency of the improved converter at the output power of 115 W may reach 83.4%. The improvement of the efficiency is made, mainly because the zero-current switching of the inverter-side switching transistors greatly reduces the switching loss in the light-load case.
[0061] Experiments have proved that the improved phase-shift converter of the present invention may stably operate in the light-load case, and the output voltage linearly changes with the phase-shift duty ratio 0 .
[0062] FIG. 11 is a diagram of transformer primary voltage and current of the present invention at output power of 115 W in the experiments. FIG. 12 is a diagram of drain-source voltage, drain current and gate voltage of transistor Q 2 which shows its switching under zero current condition. FIG. 13 is a diagram of drain-source voltage, drain current and gate voltage of transistor Q 4 which shows its switching under zero voltage condition. The primary current and voltage of transformer in FIG. 11 conform to the proposed theory very well, and the ZCS and ZVS are perfectly accomplished by Q 2 at left-leg and Q 4 at right-leg of inverter bridge as illustrated in FIG. 12 and FIG. 13 respectively, where Q 2 switches on under zero current at t=0 μp, and Q 4 switches on under zero voltage at t=6 μs when the drain-source voltage of MOSFET already reaches 0V.
[0063] The foregoing description merely shows preferred embodiments of the present invention and is not intended to limit the protection scope of the present invention.
|
The present invention discloses a soft-switching bidirectional phase-shift converter with an extended load range, which is in particularly applicable to system for the fast charging of electric vehicles in various occasions, comprising an inverter bridge, a rectifier bridge, a transformer connected between the output side of the inverter bridge and the input side of the rectifier bridge, and an equivalent inductor representing the leakage inductance of a primary side of the transformer, wherein a DC input voltage is applied to the input side of the inverter bridge, and an output load is connected to the output side of the rectifier bridge. The phase-shift converter provided by the present invention is applicable to light-load cases, without influencing the operation in heavy-load cases, so the available load range of the present charger is extended compared to conventional phase shift converters.
| 7
|
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of copending application Ser. No. 606,778 filed Aug. 22, 1975 now U.S. Pat. No. 3,996,276, and claims subject matter restricted from that application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to polycyclic amides of phosphorous acid. More specifically, it relates to bicyclic and tricyclic triamides of phosphorous acid and their use as flame retardants for cotton.
2. Description of the Prior Art
Polycyclic phosphorous triamides and their carbon analogs are known, but no phosphorous triamides in which the amide nitrogens are annular hetero atoms in a single large ring are known. The closest prior art references are:
1. Stetter and Bremen, Chem, Ber., 106, 2523 (1973), disclose the following reaction: ##STR3##
2. Laube et al., Inorg. Chem., 6, 173 (1967), disclose the transamidation reaction ##STR4##
3. Petrov et al., U.S.S.R. 144,172 (1962) (C.A., 57, 5583 (1962)), disclose transamidation of phosphorous amides by heating with amines of higher boiling point than those of the amines that composed the amide groups of the initial amides.
SUMMARY OF THE INVENTION
In accordance with this invention, polycyclic phosphorous triamides have been discovered which are of the formula: ##STR5## in which R 1 and R 2 , alike or different are alkylene of 2 to about 6 carbons containing at least 2 carbons in the backbone, and
R 3 and R 4 , alike or different, are alkyl of 1 to about 8 carbons, cycloalkyl of 5 to about 8 carbons, or aralkyl where the aryl group is of 6 to about 12 carbons and the alkyl is of 1 to about 8 carbons, or
R 3 and R 4 are joined together to form a divalent group selected from the group consisting of alkylene of 2 to about 6 carbons containing at least 2 carbons in the backbone, ##STR6## --R 5 --O--R 6 --, and --R 5 --O--R 6 --O--R 7 -- where
R 5 , r 6 and R 7 , alike or different, are alkylene of 2 to about 6 carbons containing 2 to 3 carbons in the backbone, and
Q is hydrogen or alkyl of 1 to about 18 carbons.
and when the triamide is tricyclic, at least one of the chains between the nitrogens linked to phosphorus contains at least three atoms in the backbone.
DETAILED DESCRIPTION OF THE INVENTION
The compounds of this invention are bicyclic phosphorous triamides of the formula ##STR7## and, when R 3 and R 4 are joined together to form an alkylene group or interrupted alkylene group, the compounds are tricyclic phosphorous triamides of the formula ##STR8##
Examples of suitable R 3 and R 4 groups include alkyl such as methyl, propyl, t-butyl, and 1-ethyl-3-methylpentyl; cycloalkyl such as cyclopentyl and 2-methylcyclohexyl; and aralkyl such as benzyl, 1-naphthylmethyl, 1-methylphenethyl, and 7-phenylheptyl.
Suitable examples of R 1 , R 2 , and R 8 include ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, 1,2-dimethylethylene, 2,2-dimethyltrimethylene, 1,3,3-trimethyltrimethylene. In compounds of formula (1) R 1 and R 2 are usually ethylene, --CH 2 CH 2 --, because of availability of the starting materials. When the compound is of formula (2), suitable examples of R 8 also include 3-azapentamethylene, 3-methyl-3-azapentamethylene, 3-octadecyl-3-azapentamethylene, 3-oxapentamethylene, and 3,6-dioxaoctamethylene.
Because it makes the products of formula (2) easier to form, at least one of R 1 , R 2 , and R 8 should contain at least three atoms in the backbone. When R 8 is of the formula ##STR9## suitable examples of Q include hydrogen, methyl, ethyl, isopropyl, t-butyl, isopentyl, 2-ethylhexyl, dodecyl and octadecyl. Preferably Q is hydrogen or a C 1 to C 8 alkyl group.
When R 8 is of the formula --R 5 --NH--R 6 --, the resulting product is a tautomeric mixture illustrated by the following structures: ##STR10## These tautomeric forms are designated P(III) and P(V) based on the valence state of the phosphorus in the particular structure. Whether the product exists as principally P(III), principally P(V) or a mixture of these forms will depend on ring size and the location of the nitrogens in the starting cyclic polyamine. In some cases, the P(III) structure itself has tautomeric forms, for example ##STR11##
In the claims, the products are designated by a P(III) structure. It is to be understood that this structure is intended to include the tautomeric isomers of the designated product.
The P(III)/P(V) tautomeric ratio can be determined by 31 P-nmr. In this determination the chemical shifts, ppm from standard H 3 PO 4 , are assigned the same sign convention as in 1 H-nmr. This characterization has a sensitivity of about 5%. In other words, an nmr spectra which indicates a pure tautomeric form does not preclude the presence of up to about 5% of another isomer.
The products of the invention are prepared by reacting the appropriate polyamine with a hexa(lower alkyl)phosphorous triamide (also known as a tris[di(lower alkyl)amino]phosphine). The process can be represented by the following equation: ##STR12## The chemical reaction involved is a transamidation, or amine exchange. The boiling point of the resulting di(lower alkyl) amine, R 2 NH, should be lower than that of either of the starting materials or of the polycyclic triamide product.
Suitable 1,7-dihydrocarbyldialkylenetriamines of the formula R 3 --NH--R 1 --NH--R 2 --NH--R 4 for forming the bicyclic triamides of formula (1) are known, for example, 1,7-dimethyldiethylenetriamine, 1,7-bis(1-methylheptyl)diethylenetriamine, 1,7-dicyclopentyldiethylenetriamine, and 1,7-dibenzyldiethylenetriamine. These starting materials may be prepared by known alkylation methods such as reductive amination of an aldehyde or ketone. Reductive amination with an aldehyde is carried out in accordance with the equation: ##STR13## where R 9 CH 2 --and R 10 CH 2 -- are R 3 and R 4 respectively.
Diethylenetriamine can be prepared by known methods. The higher dialkylenetriamines may be prepared by adaptations of these methods.
The cyclic polyamines used as starting materials for preparing the tricyclic triamides of formula (2) are prepared by the method outlined by Richman and Atkins in J. Amer. Chem. Soc., 96, 2268 (1974). Suitable examples of these cyclic polyamines include 1-oxa-4,7,10-triazacyclododecane, 1,4-dioxa-7,10,13-triazacyclopentadecane, 1,4,7,-triazacyclodecane, 1,5,9-triazacyclododecane, 1,8,15-triazacycloheneicosane, 1,4,8-triazacycloundecane, and 1,4,7,10-tetraazacyclododecane.
Hexamethylphosphorous triamide is the preferred triamide starting material, since it is commercially available and the resulting dimethylamine, bp 7° C., is easily eliminated from the reaction mixture.
The products of the invention are colorless, crystalline solids or colorless liquids that can be purified by sublimation and/or distillation. They are hydrolyzed by water and react slowly with atmospheric moisture and oxygen at room temperature. These products are useful as flame retardants for cellulosics such as cotton.
EXAMPLES OF THE INVENTION
The following examples illustrate the invention. All preparations were carried out in an atmosphere of nitrogen. Mass-spectral analyses were relied on to confirm the empirical formulas of the products. In each example, the product is designated by the predominant tautomeric structure.
EXAMPLE 1
10-Oxa-1,4,7-triaza-13-phosphatricyclo[5.5.1.0 4 ,13, ] tridecane is prepared as follows: ##STR14##
A. A solution of 2.50 g of 1-oxa-4,7,10-triazacyclododecane and 2.35 g of hexamethylphosphorous triamide in 25 ml of toluene is refluxed for 40 hours. It is then concentrated to dryness in a rotary evaporator, to give 2.97 g (100%) of 10-oxa-1,4,7-triaza-13-phosphatricyclo[5.5.1.0 4 ,13 ]tridecane as a brittle, white solid. Sublimation at 80° C. (0.007 mm) gives 2.08 g of white crystals having a melting point of 68°-70° C.
An infrared absorption spectrum of this material in mineral oil shows absorptions at 3.5, 6.82, 7.38, 7.59, 8.00, 8.24, 8.50, 8.83, 9.69, 9.89, 10.55, 11.18, 11.77, and 12.56μ.
B. 10-Oxa-1,4,7-triaza-13-phosphatricyclo[5.5.1.0.sup. 4,13 ]tridecane is obtained in the absence of a solvent by heating 10.0 g of 1-oxa-4,7,10-triazatricyclododecane and 9.40 g of hexamethylphosphorous triamide at 75° C. for 2 hours, by which time evolution of dimethylamine is complete. The product is sublimed at 80° C. (0.40 mm) and identified by comparison of its infrared absorption spectrum with that of the product of part A. Mass-spectral analysis of this sample shows an M + ion at 201; measured mass, 201.1094; calc'd, 201.1031; which confirms the empirical formula of the product of part A.
If 1,4-dioxa-7,10,13-triazacyclopentadecane were used in place of 1-oxa-4,7,10-triazacyclododecane in essentially the procedure of Example 1, the product would be ##STR15##
EXAMPLE 2
1,4,7-Triaza-11-phosphatricyclo[5.3.1.0 4 ,11 ] undecane is prepared as follows: ##STR16##
A. A solution of 5.00 g of 1,4,7-triazacyclodecane and 5.70 g of hexamethylphosphorous triamide in 50 ml. of toluene is refluxed for 48 hours. The toluene is removed under reduced pressure, and the residue is distilled through a short-path column, to give 5.31 g (89%) of 1,4,7-triaza-11-phosphatricyclo[5.3.1.0 4 ,11 ] undecane as a clear, colorless liquid having a boiling point of 96°-98° C. at 0.70 mm. The product solidifies on standing at room temperature.
The infrared absorption spectrum (neat) of the product has absorptions at 3.5, 6.77, 7.01, 7.50, 7.78, 8.00, 8.24, 8.50, 8.78, 8.91, 9.12, 9.83, 10.10, 10.30, 10.8, 11.4, 12.4, and 12.8 μ.
B. 1,4,7-Triaza-11-phosphatricyclo[5.3.1.0 4 ,11 ]undecane is prepared in the absence of a solvent by heating the reactants of part A at 75° C. for 1.5 hours, during which time dimethylamine is evolved. Distillation gives 5.48 g (92%) of the desired product which boils at 84°-86° C. at 0.30 mm. The product is identified by comparison of its infrared absorption spectrum with that of the product of part A. Mass-spectral analysis shows an M + ion at 171; measured mass, 171.0944; calc'd, 171.0925; which confirms the empirical formula of the product of part A.
EXAMPLE 3
1,5,9-Triaza-13-phosphatricyclo[7.3.1.0 5 ,13 ]tridecane is prepared as follows: ##STR17##
A mixture of 4.20 g of 1,5,9-triazacyclododecane and 4.00 g of hexamethylphosphorous triamide is heated at 100° C. for about 6 hours, by which time evolution of dimethylamine is complete. Distillation under reduced pressure gives 3.70 g (76%) of 1,5,9-triaza- 13-phosphatricyclo[7.3.1.0 5 ,13 ]tridecane as a clear, colorless liquid which boils at 104°-135° C. at 0.60 mm. The product solidifies at room temperature. Its infrared absorption spectrum (neat) shows absorptions at 3.5, 6.85, 7.01, 7.52, 7.73, 8.00, 8.27, 8.66, 8.90, 9.02, 9.36, 9.56, 10.27, 10.89, 11.42, 11.73, 11.97 and 14.7 μ. The mass spectrum shows an M + ion at 199; measured mass, 199.1264; calc'd, 199.1238.
If 1,8,15-triazacycloheneicosane were used in place of 1,5,9-triazacyclododecane in essentially the procedure of Example 3, the product would be ##STR18##
EXAMPLE 4
1,4,8-Triaza-12-phosphatricyclo[6.3.1.0 4 ,12 ]dodecane is prepared as follows: ##STR19##
A mixture of 3.62 g of 1,4,8-triazacycloundecane and 3.75 g of hexamethylphosphorous triamide is heated to 125° C. with stirring and held at this temperature for 2 hours, by which time evolution of dimethylamine is complete. Evolution is vigorous for the first 45 minutes. Distillation affords 3.20 g (75%) 1,4,8-triaza-12-phosphatricyclo[6.3.1.0 4 ,12 ]dodecane as a water-white liquid which boils at 73°-75° C. at 0.30 mm.
The infrared absorption spectrum (neat) of the product has absorptions at 3.5, 7.46, 7.51, 8.00, 8.23, 8.70, 8.82, 8.96, 9.31, 9.78, 10.05, 10.5, 11.5, 11.7, and 14.4 μ. The mass spectrum shows an M + ion at 181; measured mass, 181.1117; calc'd 181.1082.
EXAMPLE 5
2,8-Dimethyl-2,5,8-triaza-1-phosphabicyclo[3.3.0]octane is prepared as follows: ##STR20##
A mixture of 5.00 g of 1,7-dimethyldiethylenetriamine and 6.22 g of hexamethylphosphorous triamide is heated to 80° C., at which temperature dimethylamine begins to be evolved. Evolution of dimethylamine continues for about 1 hour, during which time the temperature is gradually raised to 125° C. The mixture is distilled to give 5.75 g (95%) of 2,8-dimethyl-2,5,8-triaza-1-phosphabicyclo[3.3.0]octane as a clear, colorless liquid, which boils at 55°-65° C. at 0.30 mm. The nuclear magnetic-resonance spectrum (C 6 D 6 /TMS) of the product shows a highly split pattern from δ 2.0 to 4.5 and has the expected sharp doublet for the --CH 3 groups at δ2.55, J = 10 Hz. The infrared absorption spectrum (neat) has absorptions at 3.5, 6.83, 6.91, 7.65, 7.80, 8.20, 8.68, 9.20, 9.70, 10.15, 10.4, 10.7, and 11.5 μ.
On standing overnight at room temperature, the product turns into an immobile glass. This transformation can be inhibited by storage at a sufficiently low temperature.
If 1,7-dicyclopentyldiethylenetriamine were substituted for 1,7-dimethyldiethylenetriamine in essentially the procedure of Example 5, the product would be ##STR21##
If 1,7-dibenzyldiethylenetriamine were substituted for 1,7-dimethyldiethylenetriamine in essentially the procedure of Example 5, the product would be 2,8-dibenzyl-2,5,8-triaza-1-phosphabicyclo[3.3.0]octane. ##STR22##
EXAMPLE 6
1,4,7,10-Tetraaza-13-phosphatetracyclo[5.5.1.0 4 ,13.0 10 ,13 ]tridecane is prepared as follows: ##STR23##
A. A solution of 1.75 g of 1,4,7,10-tetraazacyclododecane and 1.63 g of hexamethylphosphorous triamide in 50 ml of toluene is refluxed for 12 hours. Titration of the off-gases with 1 N HCl indicates that 97% of the theoretical amount of dimethylamine is evolved in this time. The toluene is removed under reduced pressure to give 2.0 g of 1,4,7,10-tetraaza-13-phosphatricyclo[5.5.1.0 4 ,13 ]tridecane as a white solid which melts at 109°-111° C. with sintering from 90° C. (possibly because of the presence of a trace of toluene). Sublimation of this product at 75° C. and 0.55 mm gives large colorless crystals, which melt at 111°-113° C. The mass spectrum shows an M + ion at 200; measured mass, 200.1194; calc'd, 200.1190.
B. 1,4,7,10Tetraaza-13-phosphatricyclo[5.5.1.0 4 ,13 ]tridecane is prepared in the absence of a solvent by heating 5.0 g of 1,4,7,10-tetraazacyclododecane and 4.7 g of hexamethylphosphorous triamide together at about 75° C for between two and three hours and subliming the crude product at 75° C. at 0.4 mm. The yield is 5.3 g (92%) of product melting at 106°-108° C.
The nmr spectra of this material show absorptions at:
(60 MHz, 1 H, CDCl 3 /TMS) δ 6.88 (1H, d, J = 628 Hz), 3.4-2.4 (16 H, m); ( 31 P, C 6 D 5 , ext. H 3 PO 4 ) δ -54.5 (d, J = 621 Hz); ( 13 C, C 6 D 6 ) δ 44.97 (d, J = 8.8 Hz).
The infrared absorption spectrum of the product in mineral oil has absorptions at 3.05 (very weak), 4.31, 7.51, 8.00, 8.20, 8.36, 8.92, 9.50, 10.22, 10.5, 11.5, 13.4 and 14.6 μ.
Measured mass (mass spec): 200.1226.
The infrared absorption of the product shows that it exists in tautomeric equilibrium with the structure ##STR24##
If 1-ethyl-1,4,7,10-tetraazacyclododecane were used in place of 1,4,7,10-tetraazacyclododecane in essentially the procedure of Example 6, the product would be of the formula ##STR25##
If 2,2,4,10,10,12-hexamethyl-1,5,9,13-tetraazacyclohexadecane were the starting material, the product would be of formula ##STR26##
EXAMPLE 7
1,4,8,11-Tetraaza-14-phosphatetracyclo[6.5.1.0 4 ,14 .0 11 ,14 ]tetradecane is prepared as follows: ##STR27##
A mixture of 4.00 g (21.5 mmol) of 1,4,7,10-tetraazacyclotridecane and 3.50 g (21.5 mmol) of hexamethylphosphorous triamide is heated for 2 hr under nitrogen at 125° and then distilled under vacuum to give 3.84 g (83%) of clear, colorless, viscous liquid 1,4,8,11-tetraaza-14-phosphatetracyclo[6.5.1.0 4 ,14.0 11 ,14 ]tetradecane, bp 92° (0.30 mm).
The infrared spectrum of this material (neat) has absorbances at 3.50, 4.43 (ν P-H ), 4.53, 6.84, 7.52, 7.8-8.8 (broad envelope), 9.10, 9.40, 9.64, 10.25, 11.1-11.5 (broad), 11.90, 13.95, and 14.9 μ.
The nmr spectra of this material have absorbances at: (60 MHz, 1 H, C 6 D 6 /TMS) δ 7.11 (1H, d, J = 609 Hz), 3.5-2.3 (16H, m), 1.42 (2H, octet); ( 31 P, C 6 D 6 , ext H 3 PO 4 ) δ -- 61.1, J = 606 Hz; ( 13 C, C 6 D 6 /TMS) δ 47.4 (d, J = 9.8 Hz), 47.1, 44.6 (d, J = 7.3 Hz), 44.0 (d, J = 7.3 Hz), and 25.0 (d, J = 1 Hz).
A similarly prepared sample shows a dominant M--H ion in the mass spectrum at m/e 213.1254 (calcd m/e 213.1268, C 9 H 18 N 4 P).
EXAMPLE 8
1,4,8,11-Tetraaza-15-phosphatetracyclo 6.6.1.0 4 ,15.0 11 ,15 ]pentadecane is prepared as follows: ##STR28##
A stirred mixture of 4.90 g (30 mmol) of hexamethylphosphorous triamide, 6.00 g (30 mmol) of 1,4,8,11-tetraazacyclotetradecane, and 30 ml of dry toluene is heated to 80°-90°, under nitrogen for 16 hr, then refluxed for 8 hr. The hot solution is filtered under N 2 and concentrated, and the residue is sublimed at 60°-70° (0.3 mm) to give 5.45 g (80%) of waxy, white solid 1,4,8,11-tetraaza-15-phosphatetracyclo[6.6.1.0 4 ,15.0 11 ,15 ]pentadecane.
The infrared spectrum of this material (nujol) has absorptions at 4.77 (ν P-H ), 7.51, 7.81, 8.02, 8.36, 8.63, 9.20, 9.47, 9.82, 10.29, 10.40, 11.05, 11.54, and 14.0 μ.
The nmr spectra of the material have absorbances at: (220 MHz, 1 H, C 6 D 6 /TMS) δ 5.84 (1H, d, J = 549 Hz), 3.20 (4H, broad mult.), 3.01 (4H, broad mult.), 2.52 (8H, sharp unsym, mult.), 1.60 (4H, sharp, unsym. mult.); ( 31 P, C 6 D 6 , ext H 3 PO 4 ) δ -53.1 (d, J PH = 547 Hz), 111.9 (minor). The relative integral of the two 31 P absorbances indicates that the product has a P(III)/P(V) tautomeric ratio of 18/82.
A similarly prepared sample shows an M + ion in the mass spectrum at m/e 228.1524 (calcd m/e 228.1503, C 10 H 21 N 4 P) and a strong M--H ion at m/e 227.1459 (calc'd m/e 227.1424, C 10 H 20 N 4 P).
EXAMPLE 9
1,5,9,12-Tetraaza-15-phosphatricyclo [7.5.1.0 5 ,15 ]pentadecane is prepared as follows: ##STR29##
A stirred mixture of 6.00 g (30 mmol) of 1,4,7,11-tetraazacyclotetradecane and 4.90 g of hexamethylphosphorous triamide is heated under nitrogen for 3 hr at 120° and then distilled in a short-path apparatus to give 5.50 g (80%) of clear, colorless liquid 1,5,9,12-tetraaza-15-phosphatricyclo[7.5.1.0 5 ,15 ]pentadecane, bp 106°-110° (0.30 mm), which solidifies on storing below 0°.
The infrared spectrum of this material (neat) has absorptions at: 2.99 (w), 3.43, 4.60 (w, ν P-H ), 6.82 6.96, 7.40, 7.60, 7.67, 7.93, 8.10, 8.47, 8.73, 8.83, 9.13, 9.62, 9.87, 10.00, 10.5, 11.7, 12.5, 14.0, 14.8 μ.
The nmr spectrum of this material has absorptions at: ( 31 P, C 6 D 6 , ext H 3 PO 4 ) δ 115.5, 112.9, 111.6, -53.0. The relative integral of the 31 P absorbances indicates 88-90% P(III) structures. ##STR30## and 10-12% P(V) structure.
The mass spectrum of similarly prepared material has a parent ion at m/e 228.1508 (calc'd) m/e 228.1503) and other peaks at m/e 227 (M--H), 213, 200, 199, 172.
EXAMPLE 10
1,5,9,13-Tetraaza-17-phosphatricyclo[7.7.1.0 5 .17 ]heptadecane is prepared as follows: ##STR31##
A mixture of 2.3 g of 1,5,9,13-tetraazacyclohexadecane and 1.8 g of hexamethylphosphorous triamide is heated under nitrogen at 125° for 2 hr and then distilled in a Kugelrohr apparatus to give 1.6 g of colorless liquid 1,5,9,13-tetraaza-17-phosphatricyclo[7.7.1.0 5 ,17 ]heptadecane, bp 110°-120° (0.1 mm), which solidifies on cooling to a white solid. The infrared spectrum of this material (CHCl 3 solution) has an absorption at 3.05 μ (ν N-H ). The mass spectrum of this material shows ions at m/e 256, 255, 213, 157, 143, 84, 70, 58, 56 and 44.
A similar experiment with distillation of the product gives 76% yield of colorless liquid, bp 132°-135° (0.3 mm), which solidifies at room temperature.
The infrared spectrum (nujol) of this material has absorptions at 3.03, 7.45, 7.95, 8.55, 8.73, 8.95, 9.14, 9.43, 9.74, 10.98, 11.13, 11.28, 14.2 μ.
The nmr spectra of this material have absorptions at: (60 MHz, 1 H, C 6 D 6 /TMS) δ 3.8-2.3 (16H, broad envelope), 2.0-1.0 (9H, broad envelope), ( 31 P, C 6 D 6 , ext H 3 PO 4 ) δ 104.8, ( 13 C, C 6 D 6 /TMS) δ 49.7 (d, J = 37 Hz) 47.0 (d, J = 10 Hz), 46.7 (s), 44.9 (d, J = 7 Hz), 28.0 (d, J = 6 Hz) and 24.3 (s).
The products of the invention are useful as flame-retarding agents for cotton articles, as shown in the following examples.
EXAMPLE A
Two solutions are prepared, each containing the products of Example 1 or Example 6 in dimethylformamide (10 weight/volume %). Cotton swabs are soaked in these solutions, some for 10 minutes and some for 1 hour and all are dried overnight. Both the treated swabs and an untreated control are tested for flammability by holding them to a flame. The untreated control burns completely and glows after the flame extinguishes. All the treated swabs are self-extinguishing when removed from the flame; the swabs themselves are charred.
EXAMPLE B
Strips of cotton cloth are soaked overnight in 10 weight/volume % solutions of the products of Examples 1 and 6 in dimethylformamide and then dried. The treated fabrics, together with an untreated control, are tested for flammability by being held vertically and touched with a flame at their bottoms. The untreated control burns profusely. The fabric treated with the product of Example 1 self-extinguishes in less than 1 second and burns less than 5% of its length. The fabric treated with the product of Example 6 self-extinguishes in about 1 second and also burns about 5% of its length.
|
Polycyclic phosphorous triamides of the formula ##STR1## in which R 1 and R 2 , alike or different, are alkylene of 2 to about 6 carbons;
R 3 and R 4 , alike or different, are alkyl of 1 to about 8 carbons, cycloalkyl of 5 to about 8 carbons, or aralkyl where the aryl group is of 6 to about 12 carbons and the alkyl is of 1 to about 8 carbons; or R 3 and R 4 are joined together to form an alkylene group of 2 to about 6 carbons which may be interrupted by
1. a ##STR2## group where Q is hydrogen or alkyl of 1 to about 18 carbons, or 2. ONE OR TWO --O-- linkages;
There are at least 2 carbons between each two hetero atoms in the outer ring system, and when the triamide is tricyclic, at least one of the chains between the nitrogens linked to phosphorus contains at least three atoms
Are useful as flame retardants for cotton.
| 3
|
FIELD OF THE INVENTION
This invention directed to an auto stand for firearms holds a firearm in an upright position. Such an auto gun stand is useful in many situations that permit the firearm to be supported independently leaving the users hands free.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in greater detail hereinafter by reference to the accompanying drawings, wherein:
FIG. 1 is a side view of the auto stand.
FIG. 2 is a front view of the auto stand.
FIG. 3 is an overall view of the auto stand.
FIG. 4 is a top view of the auto stand.
FIG. 5 is a view of the auto stand in combination with a semi-automatic pistol. It also shows how the pistol will sit on the auto stand.
FIG. 6 is a cut-away view of the auto stand.
DETAILED DESCRIPTION OF THE INVENTION
The auto stand A will hold a gun or guns in the upright position without any outside added support mechanism. This is useful to display the gun for show or to hold the gun for cleaning or repairing the gun. The auto stand A may also be used to steady one's hand while firing the gun G. Because of the design of the auto stand A, one stand can be used to support a variety of different handguns.
Auto stand A includes a base member 3 that includes a rectangular block with flat upper and lower surfaces to support the rest of the stand as well as the associated gun on a surface. A frusta-conical member 2 is attached above and supported by base member 3. The frusta-conical member 2 is responsible for holding within and supporting magnet 1 as well as metal plates 1' located on either side of magnet 1 (see FIGS. 4 and 6). The metal plates 1' on either side of magnet 1 are 1" by 1 3/4" with a thickness of 1/8". The magnet 1 is located toward the center of the auto stand A. The frusta-conical member 2 has a flat upper surface 5 upon which the gun G rests. The materials that make up base member 3 and frusta-conical member 2 of the auto stand A can be selected from the group of resin, stone, concrete, carbon, plastic, wood, or any non-ferrous material. These members can be painted, dyed, stained, and/or polished for the desired aesthetic effect. These members can be made of different shapes and styles as needed for each particular display or usage.
The auto stand A functions as follows. The handle of the pistol or gun G is placed over the magnet 1 located toward the middle of the auto stand. Since the handle of most conventional guns is made of a metal material, the magnet 1 will attached to the handle and hold the gun in an upright position. Guns that have a metal clip with a flat bottom at the lower portion of the handle will fasten to the magnet of the auto stand without alteration. Guns that do not have a flat bottom can be altered by adding a metal plate to the clip of the gun. The magnet 1 will use this clip to attach the gun to the auto stand A.
|
This invention is directed to an auto stand A for supporting a gun G in an unassisted fashion. A magnet 1 located within auto stand A attaches to the lower portion of the handle to provide the needed support.
| 5
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a self-locking device for a table elevating screw, with which a nut of the screw is prevented from dropping down when a power associated is removed or disappeared.
[0003] 2. Description of the Prior Art
[0004] Lifting and lowering operations are generally involved in mechanical devices. For the most part, the lifting and lowering operations are achieved pneumatically and hydraulically for the current mechanical devices. However, since the pneumatic and hydraulic mechanisms are susceptible to the physical factors of pressure and temperature, the objects lifted and lowered are difficult to be well positioned, apt to shift, and moved without good self-locking result, fine precision and proper reliability. Further, such pneumatic and hydraulic mechanisms are difficult to be designed. The pneumatic and hydraulic mechanisms can only provide a vertical positioning operation and require various peripheral elements and components for maintenance use. Accordingly, the pneumatic and hydraulic mechanisms cannot provide a good and convenient lifting and lowering operation.
[0005] In a hoist or an elevator, a braking or self-locking device has to be provided for the screw in prevention of dropping down of the nut of the screw when a power associated is removed or disappeared.
[0006] In the U.S. Pat. No. 2,804,053, an actuator was disclosed, which comprises a hydraulic cylinder 10 , a piston 15 , a screw 25 and a braking assembly 24 . A hydraulic oil is instilled from an upper hydraulic entrance 14 and a lower hydraulic entrance 13 so as to cause the piston 15 to ascend and descend. Meanwhile, the vertical movement of the piston 15 also brings the screw 25 to rotate. The braking assembly 24 provides a braking operation by the hydraulic pressure. When the actuator is in a stop state, the braking assembly 24 is operated to be in a locking state. When the actuator is ready to move, the braking assembly 24 is operated to be in a release state. However, complex peripheral devices are required to control the hydraulic system to have a self-locking result.
[0007] In view of the above demerits encountered in the prior art, the inventors sets forth a simple and precise self-locking device, with which the issues of difficult positioning, inconvenient installation and poor self-locking performance can be successfully overcome, effectively promoting convenience and use of the mechanical lifting and lowering mechanisms.
SUMMARY OF THE INVENTION
[0008] Therefore, the present invention is to provide a self-locking device for a lifting/rising screw, in which only simple elements are involved to achieve a precise self-locking function for the screw by means of friction forces occurred between elements when the screw is rotated in a single direction.
[0009] In accordance with the present invention, the self-locking device for a table elevating screw comprise a rotatable disk having a plurality of guide bevels thereon, wherein each adjacent two of the plurality of guide bevels has a stop bump therebetween; a wedge body has an upper surface being a frictional surface and a lower surface being a sliding surface, wherein the sliding surface is amounted on the guide bevel; an outer cover is disposed on the wedge body; and a stop plate is disposed over the outer cover with a gap, wherein when the rotatable disk rotates in a direction, the wedge bump is elevated from a low position to a high position along the guide bevel to cause the plurality of wedge bumps to bring the outer cover to rise with the frictional surface thereof, so as to generate a sliding friction between the outer cover and the stop plate to limit the table elevating screw from rotating, while when the rotatable disk rotates in the other direction, the wedge bump is lowered from the high position to the low position to cause the outer cover to move downwards and maintain a gap between the outer cover and the stop plate, so as to rotate the table elevating screw, wherein the frictional force existing between the guide bevel of the rotatable disk and the wedged body is less than the frictional force provided between the inner surface of the outer cover and the frictional surface of the wedge body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The drawings disclose an illustrative embodiment of the present invention which serves to exemplify the various advantages and objects hereof, and are as follows:
[0011] FIG. 1 is a cross sectional view of a self-locking device in a self-locking state according to the present invention;
[0012] FIG. 2 is a cross sectional view of the self-locking device in a non-self-locking state according to the present invention;
[0013] FIG. 3 is a schematic diagram of a partial structure of the self-locking device according to the present invention;
[0014] FIG. 4 is a perspective view of the self-locking device according to the present invention;
[0015] FIG. 5 is a top view of the self-locking device according to the present invention;
[0016] FIG. 6 is a partial view of another structure of the self-locking device according to the present invention;
[0017] FIG. 7 is a perspective diagram of yet another structure of the self-locking device according to the present invention;
[0018] FIG. 8 is a top view of yet another structure of the self-locking device according to the present invention;
[0019] FIG. 9 is a partial view of yet another structure of the self-locking device according to the present invention;
[0020] FIG. 10 is a perspective diagram of still another structure of the self-locking device according to the present invention;
[0021] FIG. 11 is a top view of still another structure of the self-locking device according to the present invention;
[0022] FIG. 12 is a partial view of still another structure of the self-locking device according to the present invention;
[0023] FIG. 13 is an exploded view of the table elevating screw with the self-locking device applied thereto according to the present invention;
[0024] FIG. 14 is a cross sectional view of the table elevating screw with the self-locking device applied thereto according to the present invention;
[0025] FIG. 15 is a cross sectional view of the table elevating screw with the self-locking device applied thereto according to the present invention;
[0026] FIG. 16 is a diagram depicting a self-locking state of the table elevating screw with the self-locking device applied thereto according to the present invention; and
[0027] FIG. 17 is a diagram depicting a non-self-locking state of the table elevating screw with the self-locking device applied thereto according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] Referring to FIG. 1 and FIG. 3 , a self-locking device of the present invention comprises a rotatable disk 2 , a wedged bump 3 , an outer cover 4 and a stop plate 5 .
[0029] The rotatable disk 2 is shaped like a disk and has a plurality of (al least two) guide bevels 21 thereon. Between two adjacent ones of the plurality of guide bevels 21 , there is a stop body 22 formed for isolation thereof.
[0030] The wedged body 3 is substantially shaped like a conical body, and has an upper surface being a frictional surface 3 1 and a lower surface being a sliding surface 32 . The wedged body 3 is disposed on the guide bevel 21 with its sliding surface 32 contacted with the guide bevel 21 . In this manner, the wedged body 3 is slid able on the guide bevel 21 .
[0031] The outer cover 4 is substantially shaped like a cover body and disposed on a top surface of the wedged body 3 for covering the rotatable disk 2 and the wedged body 3 . The out cover 4 has a center and the rotatable disk 2 has an axial center, which are provided in correspondence with each other. In this manner, the outer cover 4 may move freely along the axial center of the rotatable disk 2 . The outer cover 4 further has an inner surface, which is closely contacted with the wedged body 3 so that the sliding surface 32 and the frictional surface 31 are sandwiched between the rotatable disk 2 and the outer cover 4 , respectively.
[0032] The stop plate 5 is fixedly disposed on a top surface of the outer cover 4 . The stop plate 5 may be disposed at a position with a gap maintained between the stop plate 5 and the outer cover 4 so that the stop plate 5 is in a free state. Alternatively, the stop plate 5 may be disposed so that it is closely contacted with the stop plate 5 with a friction occurring there between, referred to herein as a contacting state. As such, when the rotatable disk 2 rotates in a direction, the stop plate 5 is completely contacted with the outer cover 4 , forming a self-locking state (refer to FIG. 1 ). On the other hand when the rotatable disk 2 rotates in a reverse direction, a gap is maintained between the stop plate 5 and the outer cover 4 (refer to FIG. 2 ).
[0033] By means of the rotation of the rotatable disk 2 in the two directions, the wedged body 3 is caused to slide along the guide bevel 21 of the rotatable disk 2 upwards or downwards, and the outer cover 4 is brought to move upwards or downwards by the motion of the wedged body 3 . When the outer cover 4 moves, it maintains the state of having a gap existing with respect to the stop plate 5 or being contacted with the stop plate 5 with a friction therebetween.
[0034] That is, when the rotatable disk 2 rotates in a positive direction (refer to FIG. 1 ), the wedged body 3 slides upwards from a low position (a lowest position) to a high position (a highest position), causing the plurality of wedged body 3 to bring the outer cover 4 to elevate with the frictional surface 31 and then urge the stop plate 5 . Since a sliding friction is provided between the outer cover 4 and the stop plate 5 , the rotation of the outer cover 4 can be limited, achieving the self-locking result.
[0035] On the other hand, when the rotatable disk 2 rotates in the reverse direction (refer to FIG. 2 ), the wedged body 3 is caused to descend from a high position (a highest position) to a low position (a lowest position) on the guide bevel 21 of the rotatable disk 2 . At this time, the outer cover 4 moves downwards and maintains a gap with respect to the top plate 5 , further bringing the screw 11 to rotate.
[0036] In addition, the frictional force existing between the guide bevel 21 of the rotatable disk 2 and the wedged body 3 may be less than the frictional force provided between the inner surface of the outer cover 4 and the frictional surface 31 of the wedge body 3 .
[0037] The structure of the rotatable disk and wedged body of the self-locking device may have other embodiments, which will be described with reference to FIG. 4 to FIG. 12 .
[0038] Referring to FIG. 4 and FIG. 9 , a protrusion-and-indentation mating structure is provided between the guide bevel 21 of the rotatable disk 2 and the sliding surface 32 of the wedged body 3 with the required frictional force maintained. That is, a concaved rail 23 (or a protruding sliding bump 24 , shown in FIG. 7 ) may be provided on the guide bevel 21 of the rotatable disk 2 while a protruding bump 33 (or a concaved rail 24 , shown in FIG. 7 ) is formed on the sliding surface 32 of the wedged body 3 . As such, the rotatable disk 2 and the wedged body 3 are less likely to be worn down by each other.
[0039] Referring to FIG. 10 to FIG. 12 , a concaved structure is formed on both of the guide bevel 21 of the rotatable disk 2 and the sliding surface 32 of the wedged body 3 , indicated as 25 and 35 . Between the concaved structures 25 , 35 , a bead 7 is disposed. As such, a frictional force is presented between the concaved structures 25 , 35 , effectively reducing possibility of worn-down of the rotatable disk 2 and the wedged body 3 .
[0040] Referring to FIG. 13 to FIG. 17 , the self-locking device of the present invention is applied to a lifting/lowering mechanism 6 for a table elevating screw 1 . The lifting/lowering mechanism 6 comprises a screw shaft 11 having thread circumferentially formed and a nut 12 having thread at an inner side thereof. The screw shaft 11 and the nut 12 are provided so that they can be connected together.
[0041] The self-locking device of the present invention may be implemented in the lifting/lowering mechanism 6 as described follows.
[0042] The rotatable disk 2 may be fixed over a combination of a lifting/lowering member 61 of the lifting/lowering mechanism 6 and the screw shaft 11 .
[0043] The wedged body 3 may be slid ably disposed on the guide bevel 21 of the rotatable disk 2 .
[0044] The outer cover 4 is provided to cover the rotatable disk 2 and the wedged body 3 . A through-hole (without labeled) is formed on the rotatable disk 2 for penetration of the screw shaft 11 . In this manner, the outer cover 4 can move freely along an axial direction of the screw shaft 11 .
[0045] The stop plate 5 is disposed over the outer cover 4 and fixed on the lifting/lowering member 6 for assembling the screw shaft 11 .
[0046] Referring to FIG. 16 , when the table elevating screw 1 rotates in a positive direction on the lifting/lowering mechanism 6 , i.e. the rotatable disk 2 is brought to rotate in the positive direction by the table elevating screw 1 , a sliding friction is presented between the stop plate 5 and the outer cover 4 . At this time, the screw shaft 11 is limited in rotation and a self-locking state is occurred.
[0047] Referring to FIG. 17 , when the table elevating screw 1 is operated to rotate in a reversing direction in the lifting/lowering mechanism 6 , i.e. the rotatable disk 2 is brought to rotate in the reversing direction by the screw shaft 11 , a gap may be maintained between the stop plate 5 and the outer cover 4 . At this time, the screw shaft 1 is further caused to rotate, which brings the lifting/lowering mechanism 6 to providing the lifting and lowering operations.
[0048] In the above described self-locking device, the wedged body 3 can slide on the guide bevel 21 of the rotatable disk 2 no matter when the screw shaft 11 rotates in the positive or reverse direction, which brings the outer cover 4 to move upwards or downwards and thus the outer cover 4 maintains a gap with respect to the stop plate 5 or is closely contacted with the stop plate 5 with a friction occurring therebetween.
[0049] The self-locking device for the table elevating screw has the following features and efficacies. 1. A simple self-locking structure is achieved, where the rotatable, wedged body, outer cover and stop plate are comprised, in contrast to the conventional locking mechanism where a hydraulic or pneumatic system is involved and complex peripheral elements are required, effectively saving the manufacturing cost therefore and thus promoting convenience and use thereof. 2. The self-locking state of the screw can be precisely achieved by controlling the reaction between the outer cover and the stop plate by the wedged body on the rotatable disk, effectively exempting the screw nut from dropping downwards and achieving the purposes of vertical positioning and self-locking effect in a single direction.
[0050] In conclusion, the self-locking device for the table elevating screw is not only simple in structure but also capable of providing a precise self-locking function in a single direction by means of the friction occurring when the rotatable disk is brought to rotate by the screw shaft, effectively overcoming the issues and disadvantages inherent in the prior art, where a hydraulic or pneumatic system is involved and particularly qualifying itself as a means for precisely positioning a table elevating screw.
[0051] Many changes and modifications in the above described embodiment of the invention can, of course, be carried out without departing from the scope thereof. Accordingly, to promote the progress in science and the useful arts, the invention is disclosed and is intended to be limited only by the scope of the appended claims.
|
A self-locking device for a table elevating screw includes a rotatable disk disposed on a screw having a nut thereon, a wedged body disposed on the rotatable disk, an outer cover moveably disposed on the rotatable disk and the wedged body and a stop plate disposed on the outer cover. When the rotatable disk rotates in relation to the screw in a direction or a reverse direction, the wedged body ascends or descends in relation to the rotatable disk, maintaining a gap between the stop plate and the outer cover or generating a frictional force therebetween. By means of the frictional force occurred when the screw rotates in a single direction, the self-locking device can achieve a precise self-locking device for the screw in a lifting/lowering positioning task.
| 0
|
[0001] This application is a continuation application of U.S. Ser. No. 12/410,730, filed on Mar. 25, 2009. This application also claims priority to U.S. Provisional Patent Application No. 61/039,510, filed on Mar. 26, 2008.
FIELD OF THE INVENTION
[0002] The present invention relates to gas burners generally and more particularly to gas burners of a type suitable for use with gas cookers or cook tops.
BACKGROUND TO THE INVENTION
[0003] There are a number of known ways to provide heat to a cook top for cooking. One preferred method uses a plurality of gas burners which burn a fuel gas in order to heat cooking vessels.
[0004] The gas burners are commonly of a burner ring form. A plurality of burner rings are usually located on a cook top surface, which typically include a trivet or stand for supporting a cooking vessel at an appropriate height above each burner ring. The heat output from the burners is controlled by varying the flow rate of fuel gas supplied to the burner ring and combusted. Typically, the supply of fuel gas is regulated by a valve associated with each burner ring. A preferred form of burner is described in WO 06/006882 which is incorporated herein by reference.
[0005] Further, it is desirable that a user of a cook top has as much control over the heat output of the burner as possible. In particular it is especially desirable that fine levels of adjustment and control are available to a user at the lower end of the heat output range of the burner. Such fine control is necessary for the preparation of particular types of cuisine. It is also desirable that the burners of a cook top have the widest range of heat output possible. This may be referred to as having a high turn-down ratio. Burners with high turn-down ratios may be suitable for cooking a wide variety of cuisine. It is also preferable that the burners of a gas cook top are capable of providing repeatable levels of heat output for each power setting.
[0006] In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a context for discussing the features of the invention. Unless specifically stated otherwise, reference to such external documents is not to be construed as an admission that such documents, or such sources of information, in any jurisdiction, are prior art, or form part of the common general knowledge in the art.
[0007] It is an object of the present invention to provide an improved gas cooking appliance which goes some way to alleviating the above problems or at least provide the public with a useful choice.
SUMMARY OF THE INVENTION
[0008] In one aspect, the present invention broadly consists in a cook top comprising:
a burner, a valve operated by an actuator to vary the flow of fuel gas from a supply to said burner, a user interface configured to receive a user input indicative of a desired burner setting, a controller operationally coupled to said actuator and to said user interface, and configured to:
receive a signal from said interface, determine a desired valve position, wherein said determination utilizes a predetermined relationship between said signal received and said desired valve position, cause said actuator to move said valve to said desired position.
[0016] Preferably said actuator is a stepper motor and said step of determining said desired position includes calculating the number of steps from a current position to said desired position according to said relationship.
[0017] Preferably said actuator is a stepper motor and said step of determining said desired position comprises looking up the number of steps from a current position to said desired position in a look up table.
[0018] Preferably said predetermined relationship depends on the type of fuel gas.
[0019] Preferably said cook top includes a plurality of burners of at least two different variations or type, and
said cook top includes a valve for each said burner, and each said controller utilizes a different said predetermined relationship for each said different variations or type of burner.
[0022] Preferably said predetermined relationship is biased such that a user input indicative of a given change in desired burner setting at a lower end of the range, results in less valve adjustment than a user input indicative of a given change in desired burner setting at a higher end of the range.
[0023] Preferably said predetermined relationship is biased such that a user input indicative of a given change in desired burner setting at a lower end of the range, results in greater valve adjustment than a user input indicative of a given change in desired burner setting at a higher end of the range.
[0024] In another aspect, the present invention broadly consists in a method of controlling a valve comprising:
receiving a signal, determine a desired valve position, wherein said determination utilizes a predetermined relationship between said signal received and said desired valve position, causing an actuator to move said valve to said desired position.
[0028] Preferably said actuator is a stepper motor and said step of determining said desired valve position includes calculating the number of steps from a current position to said desired position according to said relationship.
[0029] Preferably said actuator is a stepper motor and said step of determining said desired position comprises looking up the number of steps from a current position to said desired position in a look up table.
[0030] Preferably said predetermined relationship is biased such that a signal indicative of a given change in setting at a lower end of a range, results in less valve adjustment than a signal indicative of a given change in setting at a higher end of a range.
[0031] Preferably said predetermined relationship is biased such that a signal indicative of a given change in setting at a lower end of a range, results in greater valve adjustment than a signal indicative of a given change in setting at a higher end of a range.
[0032] In another aspect, the present invention broadly consists in a cook top comprising:
a burner, a user interface configured to receive a user input indicative of a desired burner setting, a valve having a fully closed position and operated by an actuator to vary the flow of fuel gas from a supply to said burner, a controller operationally coupled to said actuator and having two modes, wherein when in a first mode:
said controller opens said valve, ignites said burner and detects the presence of a flame,
while maintaining detection of the presence or absence of said flame, progressively closes said valve until said flame is no longer detected, and records the distance between said fully closed position of said valve and the last position of said valve when said flame was detected, as a reference offset, and when in said second mode:
said controller operates said burner according to said user input.
[0043] Preferably said valve position when said flame was last detected is used as the valve position corresponding to the lowest setting of said burner.
[0044] Preferably said cook top includes a plurality of burners and said controller records a reference offset for each said burner.
[0045] Preferably said controller looks up a look up table to determine how to move said valve to get from a current position to a desired position based on said input.
[0046] Preferably said look up table includes the distance from every burner setting to every other burner setting, and
said table records said reference offset for each burner as the distance from said fully closed position to a lowest burner setting.
[0048] Preferably said look up table includes the distance from each burner setting to the next lower burner setting, and
said table records said reference offset for each burner as the distance from said fully closed position to a lowest burner setting.
[0050] Preferably said actuator is a stepper motor, and said lookup table stores a value for each burner setting that is the number of steps that that setting is above the next lowest setting, and
said table records said reference offset value for the lowest burner setting.
[0052] Preferably said actuator is a stepper motor, and the number of steps from said fully closed position to the position corresponding to each burner setting is the sum of said reference offset and all the lookup table values from the lowest setting to each burner setting.
[0053] Preferably said controller stores the current distance from said fully closed position for each valve.
[0054] In another aspect, the present invention broadly consists in a method of operating a burner comprising:
opening a valve having a fully closed position to deliver a fuel gas to said burner, igniting said burner and detecting a flame, while continuing to detect the presence or absence of said flame, progressively closing said valve until said flame is no longer detected, and recording the distance between said fully closed position of said valve and the last position of said valve when said flame was detected, as a reference offset.
[0059] In another aspect, the present invention broadly consists in a method of operating a burner comprising:
opening a fuel gas valve to supply fuel gas to a burner, igniting said burner and detecting the presence of a flame, while maintaining the detection of the presence or absence of said flame, progressively closing said valve until said flame is no longer detected, and recording the position of said valve at the last point that said flame was detected as a reference offset.
[0064] In another aspect, the present invention broadly consists in a method of operating a burner comprising:
receiving a signal indicative of a desired burner setting, looking up a look up table to determine how to move said valve to get from a current position to a desired position based on said signal, wherein said step of determining includes summing all the data in said table for each position between an off position and said desired position.
[0068] The term “comprising” as used in this specification and claims means “consisting at least in part of”. When interpreting each statement in this specification and claims that includes the term “comprising”, features other than that or those prefaced by the term may also be present. Related terms such as “comprise” and “comprises” are to be interpreted in the same manner.
[0069] This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.
[0070] The invention consists in the foregoing and also envisages constructions of which the following gives examples only. In particular, the invention has been described predominantly with reference to a single burner and valve in a cook top. It will be appreciated that this is for convenience, and that cook tops are usually equipped with multiple burners, and may even include heating elements of different types.
BRIEF DESCRIPTION OF THE DRAWINGS
[0071] Preferred embodiments of the invention will be described by way of example only and with reference to the drawings, in which:
[0072] FIG. 1 is a schematic drawing of a cook top with controller, respective burners and supply valves.
[0073] FIG. 2 is a flow chart diagram illustrating a preferred calibration method.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0074] Typically modern cook tops include a plurality of burners to accommodate multiple cooking operations simultaneously and/or provide different burner options. In one preferred form of the invention, the cook top 100 includes a controller 101 operationally coupled to a user interface and an actuator 105 associated with each valve 102 for varying the supply of fuel gas (from gas supply 106 ) to each burner 103 independently.
[0075] The user interface may take many forms such as a simple rotating control knob, a translating lever, or other user controls such as touch screens, buttons or touch controls. The user interface preferably includes a form of visual feedback so that the user can easily ascertain the current burner setting. For example, a number of LED's could be arranged in the form of a bar graph (in a linear or non-linear shape) and be progressively lit and un-lit as the burner setting increases or decreases respectively.
[0076] Preferably each burner 103 is independently controlled and the user interface provides independent visual feedback for each burner setting. The controller 101 is preferably a microprocessor and may be capable of driving each actuator 105 directly, or may utilize an amplification or motor driver circuit to control the actuators.
[0077] The gas supply valve 102 of each burner is coupled to a stepper motor 105 via a reduction gear box. An example of a suitable type of stepper motor is a 12V stepper motor with 48 steps per revolution. The step resolution of the stepper motor in combination with the reduction gear box gives the angular resolution with which the rotating gas valve is controlled. It will be appreciated that the required resolution will depend on the characteristics of the valve as well as the desired resolution of control over the fuel gas flow rate, which in turn dictates the actual burner heat output.
[0078] It has been found for example that a resolution of approximately 0.5° is appropriate for a valve of the type typically used in a domestic cook top with typical supply pressure and gas jet sizes. For example, 48 steps and a reduction of approximately 1:13 through the gearbox.
[0079] In use, a user manipulates the user control according to a desired burner setting. The controller 101 receives a signal from the user interface indicative of the desired burner setting and causes the actuator 105 to move the respective valve to the desired position. For positional control to be accurate, the motor must stay synchronized. i.e., when a phase is energised the motor must rotate to the new position, in order to make sure that the cook top controller does not lose track of the current position of the valve. Alternatively, the controller may receive a signal from a position sensor such as a rotary encoder in order to track the valve movement. To assist the motor staying synchronized at start-up and when changing direction, the current phase may be pre-energised before moving.
[0080] When the valve 102 is moved by the actuator 105 from a stationary position, the torque required to move the valve in each direction may differ due to the characteristics of the valve, gearbox and drivetrain. For example, if the last direction of movement was clockwise, and the valve is moved in a clockwise direction from stationary, the initial resistance of the valve may be higher. However, if the last direction of movement was clockwise, and the valve is moved in an anti-clockwise direction from stationary, the initial resistance of the valve may be lower, due to the slop or back-lash in the valve and drivetrain.
[0081] The worst case scenario of the stepper motor driving the gas valve is when the valve is stationary and the stepper motor begins to move the valve in the same direction as the last movement of the valve. Under these conditions the torque requirement of the motor is greatest and the potential for the motor to stall is highest.
[0082] In order to reduce the likelihood that the motor may stall causing the controller to lose track of the current position, the controller rotates the actuator motor backwards a pre-determined number of steps before rotating in the same direction as the previous movement.
[0083] Traveling in the reverse direction initially, presents a minimum load to the motor because of the slop or backlash in the drivetrain. When the motor shaft rotates back to the original position and picks up the full load it does so with some momentum, reducing the probability of losing synchronization between the actual position and position the controller is expecting. Preferably the number of steps the controller moves the valve backwards initially, corresponds approximately with the amount of slop in the drivetrain, and/or allows the motor to build rotational momentum. For example, approximately 2-3 degrees is typical for typical valve designs. The controller software may drive the valve using a number of suitable methods such as a wave or full step drive according to the required motor torque. Alternatively, a hybrid drive method such as half-step, or inverted half-step, can be used.
[0084] To further assist the valve motor in staying synchronised at start-up, the phase energisation time at start-up may be increased from its normal operating period. Longer phase times tend to produce more torque, but rotate the shaft more slowly. For example, when the motor starts moving from a stationary position each phase is energised for 8 ms, then once the valve is turning, the energisation time may be lowered to 3 ms. It will be appreciated that the foregoing valve control technique can be utilized alone or in combination with any one or more of the following described valve control techniques.
[0085] Due to the slop or backlash in the drivetrain, the positional accuracy of the valve corresponding to a particular desired burner setting (and gas flow) may also be compromised. In order to improve the positional accuracy and the repeatability of each valve position corresponding to a desired burner setting, the controller is configured to actuate the valve such that it always approaches the desired valve position from the same direction. This method ensures that the backlash in the drivetrain is treated consistently, reducing positional errors, and is therefore more repeatable. Preferably, the pre-determined amount of travel should be greater than the sum of the possible backlashes in the valve, drivetrain, and gearbox. The authors have found that the combined backlash can be higher than 30°, for some typical types of valve/gearbox combinations.
[0086] For example, if the new desired position of the valve lies in the counter clockwise direction from the current position, then the controller causes the actuator to move the valve to the desired position such that the valve arrives (at least in the terminal portion of movement) at the desired position traveling counter clockwise. However, if the new desired position of the valve lies in the clockwise direction from the current position, then the controller causes the actuator to move the valve past the desired position by a pre-determined amount, and then moves to the desired position such that the valve arrives traveling counter clockwise (at least in the terminal portion of movement).
[0087] The positional accuracy and repeatability is improved by insuring that the terminal portion of movement as the valve arrives at a new position, is always in the same direction. Preferably the direction of the terminal portion of movement is the direction that closes the gas valve. Accordingly the lowest burner setting is approached by closing the valve (i.e. turning the burner down). Similarly, the highest burner setting is approached by turning the valve in the closing direction. In order to maximize the heat output at the highest burner setting, the valve preferably has a runoff region where the valve is wide open such that further opening of the valve does not increase the flow of gases through the valve. This region also prevents the backlash movement from rotating the valve past fully open and into a closed region, which may cause the burner to go out when turning to high.
[0088] Alternatively, in another embodiment it is envisaged that not every desired valve position (corresponding to a burner setting) is approached from the same direction as all the other valve positions. For example, the valve position corresponding to the maximum burner setting may approached from the opposite direction in which the lowest setting is approached from. i.e. the maximum setting may be approached from the direction that opens the valve. In such an embodiment, the runoff region referred to above can be avoided. Similarly, it is anticipated that each of various the valve positions corresponding to each burner setting, may be approached from a different direction than some of the other valve positions. The important aspect is that for any given burner setting, the valve position corresponding to that setting, is always approached from the same side, regardless of whether or not the previous position was lower or higher. As a result, each setting is approached consistently, and therefore the positional accuracy and repeatability is improved.
[0089] It will be appreciated that the foregoing valve control techniques can be utilized alone or in combination with any one or more of the following described valve control techniques.
[0090] In order for the controller to maintain accurate control of the burner setting of each burner, it is necessary for the controller to know the current position of each valve (associated with each burner). It is also necessary that the controller knows how far to move each valve in order to achieve the appropriate fuel gas flow for any desired burner setting. It has been found that individual valves may have different angular positions that result in the same flow due to manufacturing tolerances and inconsistencies. Therefore in order for the controller to achieve accurate control, it is necessary to map each burner setting to a unique valve position for each burner. In particular gas valves typically have a fully closed position which may be associated with a mechanical limit or bump stop. I.e. At the limit of the valves rotation (in one direction) the valve will be fully closed and no fluid (or gas) can pass through. This fully closed position can be used as a convenient reference position.
[0091] However, due to manufacturing tolerances and part-to-part variation it is typical for valves of the same type to have different distances between their fully closed position and the position where the valve just begins to open and the minimum flow rate is achieved, or the minimum flow rate that can support a flame is achieved.
[0092] Despite the variation in the offset distance between the fully closed position and minimum flow of a typical valve, the distance between the minimum flow position and the highest flow position (fully open) is typically quite uniform for a given gas pressure and jet size. That is to say that once the minimum flow position is reached, the distance to any other given flow position is substantially the same from valve to valve (of the same type/model).
[0093] In order to account for these variations, the cook top of the present invention may include a calibration process. Preferably the controller can be switched into a calibration mode through the user interface and back to a normal operating mode when the calibration is complete. Alternatively, a normal operation mode may be restored automatically once calibration is complete. It will be appreciated that each burner of the cook top may need to be calibrated separately.
[0094] The burner calibration process finds the distance from the zero position of the burner valve, to the valve position producing the smallest detectable flame setting. In order to detect whether or not a flame is present on the burner, each burner is preferably equipped with a flame detector 107 . The flame detection method may be any appropriate method known in the art. For example, flame detection may be achieved electronically by applying an AC current between electrodes positioned at the expected location of a flame. The diode effect of the flame (if present) results in a partially rectified waveform, the presence of which can be used to indicate the presence of a flame. Other known methods such as thermal or optical detection could also be used.
[0095] During calibration the controller opens the valve (preferably to a position corresponding to a medium to high burner setting) and ignites the burner. In order to achieve automatic ignition the controller is operationally coupled to an igniter mechanism such as a spark igniter or hot surface igniter or other suitable igniter means. The igniter may be integrated with the flame detector 107 ). The controller then verifies that ignition was successful and is maintained through flame detection as referred to above. The controller then progressively closes the valve until the flame goes out (as detected by flame detection). The controller records the position of the valve at which the flame was last present. This position is then set as the position corresponding to the lowest burner setting. The result of the gas calibration process is stored in EEPROM. The value is the number of steps from the zero position of the valve to the smallest detectable flame, and is stored as an unsigned integer.
[0096] The distance from the fully closed position to the position at which the flame was last detected is recorded as a reference offset. This offset distance corresponds to the portion of the valve movement that may vary significantly from part to part. While the valve position of minimum flow is unlikely to correspond precisely with the burner's lowest setting position, the lowest setting position at which a flame can be detected is a suitable reference from which the valve positions corresponding to all other burner settings can be located.
[0097] It is common for a gas valve to include a by-pass port to help achieve a reliable low flow setting. The port may be adjustable via a manual by-pass screw or be fixed. It is envisaged in another embodiment that the low power setting of the burner or cooktop may include fuel gas flow through such a by-pass. The calibration method may still be employed as described above. At the low power setting, some or all of the fuel gas may be supplied via the by-pass.
[0098] Alternatively, the calibration method may utilise an adjustable by-pass where the by-pass can be controlled by the controller. In particular, the by-pass can be progressively opened if a low flame cannot be maintained and detected.
[0099] FIG. 2 is a flow chart illustrating the logic of a preferred calibration routine. In particular, to improve efficiency the controller may progressively close the valve quickly at first until the flame goes out. The controller then opens the valve, re-ignites the burner and goes to the last position where a flame was present. It then progressively closes the valve more slowly until the flame goes out. This progressive method allows the controller to more accurately locate the valve position corresponding to the lowest possible burner setting, while not being too slow. It is envisaged that many variations on the calibration process could be implemented including changes to timing, detection of the strength of the flame, averaging multiple calibrations, etc. Each of these corresponds to a further embodiment of the invention.
[0100] A calibration fault will occur if either a flame cannot be detected after ignition, or if the controller detects that the valve is not rotating properly and the valve motor is losing synchronization.
[0101] Once the reference offset is recorded, a lookup table defines the distance (number of steps) between the lowest setting (from calibration) and each of the burner setting positions. It will be appreciated that the lookup table may contain alternative values to accommodate different fuel gas types, operating pressures, jet sizes, user preferences and different burner types. The number of steps from the fully closed position of the valve to the valve position corresponding to a particular burner setting, is the sum of the reference offset value and all the lookup table values from the lowest burner setting to that particular burner setting.
[0102] In order to ensure that the controller can accurately locate the valves fully closed position, it is preferable that a limit switch or bump stop is provided. The sum of all of the look up table values for all burner settings must equal the number of steps required to position the valve corresponding to full power for the burner, without rotating the valve significantly past the point at which maximum flow is achieved. In other words, the full range of burner settings should correspond to valve positions between the lowest detectable flame position and the first position at which the maximum desired flow is achieved.
[0103] Alternatively, rather than using the bump stop as a reference, or when no such stop exists, an electrical switch can be used to provide a reference to the off position. The switch may be a mechanical rotary type, or side mounted microswitch with a cam located at an appropriate point on the drivetrain. Alternatively, an optical, or other non-contact device could be used.
[0104] Preferably, when the valve is closed the switch should be parked near the center of its closed region. The switch can be used as a safety device to ensure that the controller is aware when a valve is not properly closed. In order to achieve reliable, repeatable positioning of the valve switch, it may be preferable to implement a positional searching algorithm that centers the switch on its cam when the burner is turned off. For example, the valve may be rotated counter-clockwise until completely past the cam, then rotated clockwise until a pre-determined number of steps past the closing point of the switch. Another alternative to a mechanical stop, or an electrical switch, is to use an absolute positional encoder.
[0105] Alternatively, valve positions could be calculated via use of one or more formulae. Inputs to such equations may include gas type, pressure, and jet size. While such a formula may be advantageous in terms of memory usage, a series of lookup tables provides an increased degree of configurability with extremely low computation requirements. Each method represents an embodiment of the invention.
[0106] The foregoing description of the invention includes preferred forms thereof. Modifications may be made thereto without departing from the scope of the invention as defined by the accompanying claims.
|
A gas cook top includes a plurality of gas burners arranged on a cook top surface to accommodate a variety of cooking vessels. Each burner is associated with a valve for varying the flow of fuel gas from a supply to the burner, so that the heat output of the burner can be varied in use. The cook top includes a controller operationally coupled to an actuator associated with each valve for varying the position of each valve. The controller is configured to receive an input from a user via a user interface and operate the actuator to move a valve to a desired position along a predetermined path, wherein the path may not be the shortest distance between the current position and the desired position of the valve.
| 5
|
This application is a continuation of application Ser. No. 07/937,307, filed Aug. 31, 1992, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention first relates to a plastic filler insert for a writing fluid container, having a cylindrical neck opening which can be closed off with a cap. Writing instruments are refilled from a container which has a converter device consisting of a piston-cylinder unit for receiving and dispensing writing fluid.
The invention secondly relates to a device for filling a converter containing a writing fluid. The converter has an orifice in the shape of the orifice of a conventional ink cartridge, with a reservoir containing a writing fluid.
2. Brief Description of the Prior Art
In place of writing fluid cartridges, in particular ink cartridges, converters are employed to a great extent in writing instruments, for example fountain pens, which were originally embodied to use writing fluid cartridges. While the writing fluid cartridges are thrown away when empty, the converter permits refilling by means of a piston mechanism contained in it. More specifically, such converter devices consist of a piston-cylinder unit, by means of which writing fluid for filling the writing instrument is aspirated from a container.
Up to now, grave disadvantages arise if writing fluid containers with screw tops were used for filling converters and the orifice of the converter was dipped into the writing fluid contained in the writing fluid container and writing fluid is aspirated by means of the aspirating connector of the converter device (German Utility Model DE-GM 86 12 171). In normal use it is almost impossible in the course of refilling to dip the aspirating connector into the writing fluid with sufficient care so that soiling of at least the aspirating connector with writing fluid can be avoided, so that the user is required to clean it prior to inserting it into the writing instrument. Moreover, it is almost impossible to avoid aspirating air together with the writing fluid. If this air remains in the converter device, the writing fluid is dispensed unevenly, which interferes with the writing process.
OBJECTS AND SUMMARY OF THE INVENTION
For assured avoidance of these disadvantages, one object of the invention is to provide a special component which is simple to produce and by means of which every writing fluid container can be complemented in a simple manner. Secondly, the invention provides a device by means of which a converter can be filled in a simple manner and without becoming soiled.
The first object is attained in accordance with the invention by means of a plastic filler insert for a writing fluid container with a cylindrical neck opening which can be closed off with a cap, in that this filler insert is embodied in the form of a closure plate having a sealing edge seated on the rim of the neck opening of the container. A receiving connector, which is open toward the outside and is pointed into the interior of the container is formed on the bottom of the plate, which is continued in the interior as an aspirating hose extending toward the container bottom. The aspirating connector of the converter device can be sealingly inserted into its cylindrical receiver opening. Such a closure plate can be easily formed from plastic. Resilient plastics in particular, and also synthetic rubber materials, are intended to be this plastic. This closure plate is inserted into the container opening in the manner of a closure plug. Its sealing edge rests on the rim of the neck opening and the required tight sealing of the container in the course of placing or screwing the closure cap on the container is achieved in this way.
The main advantage achieved by means of the receiving connector is that the aspirating connector of the converter device of a writing instrument can be inserted simply, securely and especially sealingly into the receiving connector after the closure cap has been removed. Subsequently, writing fluid can be aspirated from the container into the converter device in an exactly defined and sealed position. In this way the aspirating connector of the converter has no contact with writing fluid in the container, except for the defined opening of the aspirating hose. Soiling of the aspirating connector and thus of the converter as well as the writing instrument itself, and the aspiration of air is completely prevented.
The bottom of the receiving connector also securely seals the connecting surface of the aspirating connector of the converter. Therefore, the entire filling operation can be performed simply, safely and without danger of soiling, as well as without danger of aspirating air. The closure plate and the aspirating connector with the aspirating hose can be produced of one piece of a suitable plastic.
A suitable small opening can be provided in the closure plate for letting air into the interior of the container during removal of the writing fluid.
In order to be able to continue to fill other writing instruments without converter devices and without having to remove the closure plate of the filler insert, it is practical in accordance with another embodiment of the invention to provide a through-opening in the bottom of the closure plate outside of the receiving connector, which can be closed by means of an associated insertable closure element. The size of the through-opening can be selected to be such that conventional writing instruments can be inserted for refilling. This through-opening can be securely closed by means of the insertable closure element, which can be made from the same plastic. In this connection it is advantageous to provide a gripping tab or the like on the edge of the closure element, which remains at the top inside the area of the closure plate. It is advantageous here to embody the closure element for the through-opening also in the shape of a plate-shaped closure plug, having a sealing edge placed on the outside of the closure plate bottom in such a way that the sealing edge remains inside the closure plate. Producing such a part is simple, it is safely maintained in the through-opening and the removal of this closure plug is simple.
An exemplary embodiment of this aspect of the invention, namely a filler insert for a so-called ink bottle, is illustrated in FIGS. 1 and 2.
A second object of the invention is a device for filling a converter that is embodied in accordance with the invention in such a way that the reservoir has a connector adapted for a sealing placement with the orifice of a converter. Furthermore, in the interior of the reservoir a pipe-shaped conduit segment extends from the connector as far as the bottom of the reservoir.
With a device in accordance with the invention, the converter can be sealingly connected with the reservoir, so that writing fluid transported from the reservoir into the converter cannot soil the outside of the converter. In addition, the writing fluid for the converter is taken out of the reservoir via a pipe-shaped conduit segment, which extends close to the bottom of the reservoir, so that it is not necessary to turn the reservoir over. Normally this would pose the danger of leakage of writing fluid from the reservoir.
The inner end of the conduit segment lies close to the bottom, so that all writing fluid can be taken from the reservoir. Furthermore, to prevent the inner opening of the conduit segment from coming to rest on the bottom of the reservoir, and thereby shutting off the flow of the writing fluid, the conduit segment preferably extends coaxially with the connector, in the area adjoining the connector. A conduit segment may also continue downwardly in the interior of the reservoir, with a free end that rests on the bottom of the reservoir and is inclined in relation to the bottom. In this way a sealing connection is assuredly not formed between the bottom and the inner opening of the conduit segment.
To prevent underpressure from being created in the reservoir when aspirating writing fluid out of it and into the converter, which would hamper this aspiration of writing fluid, the reservoir also preferably has an opening adjacent to the connector.
A pipe-shaped conduit segment also preferably forms a capillary conduit, so that the writing fluid in the conduit segment is always kept close to the connector when the level of writing fluid in the reservoir is lowered.
A converter-filling device in accordance with this second object will be described in more detail below, and with reference to FIGS. 3 and 4 illustrating an exemplary embodiment thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of the closure element in accordance with the invention, shown within the neck opening of a container, of which only the upper portion is shown for the sake of simplicity; and
FIG. 2 is a top view of a filler insert in accordance with FIG. 1; and
FIG. 3 is a perspective view of a reservoir with the converter placed above the reservoir in accordance with the invention; and
FIG. 4 is a sectional view through the reservoir of FIG. 3, closed by a screw cap.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The first object of the invention will now be described according to the preferred embodiment, of FIGS. 1 and 2. The upper portion of a writing fluid container 1, for example an ink bottle, is schematically shown in FIG. 1. The container 1 is closed by means of a suitable closing cap, for example a screw cap, on the upper cylindrical neck opening 2.
The filler insert is formed of plastic as a closure plate 3 and has a sealing edge 4 seated on the edge of the neck opening. A receiving connector 6, open to the outside and directed toward the interior of the container, is formed in its bottom 5. In this way the connector 6 has a cylindrical receiving opening 7, which terminates on the bottom and on the inside in a cone-shaped bottom surface 8. The receiving connector 6 continues on to form an aspirating hose 9 extending to the bottom of the container.
After removal of the closure cap, not shown in FIG. 1, from the container neck 2, the aspirating connector of a converter device of a writing instrument can be inserted into the cylindrical receiving opening 7 of the receiving connector 6. It is then possible to aspirate writing fluid from the container via the aspirating hose 9 by means of the piston-cylinder unit of the converter.
A through-opening 10 is provided in the bottom 5 of the closure plate 3 outside of the receiving connector 6. As shown in particular in FIG. 2, the receiving opening 7 of the receiving connector 6 is in this case disposed off-centered. Because of this it is possible to give the through-opening 10 sufficient width, so that the writing points of other writing instruments can be freely inserted into the interior of the container, and such writing instruments can be refilled without the aspirating connector 6. It is possible to give the contour of the through-opening 10 a shape suitable for the respective intended use. The through-opening 10 can be closed by means of an associated insertable closing element 11.
In accordance with FIG. 1, a closing plate is embodied as a plate-shaped closure plug with a sealing edge 12 resting on the closure plate bottom 5 in such a way that the sealing edge remains inside the closure plate. In a practical manner and in accordance with FIG. 2, the sealing edge 12 is formed into a gripping tab 13 to make manipulation easier.
Plastic materials are chosen to be suitable for the respective intended use. Easily resilient plastics will be employed for the closure plate 3 and the closure plug 11. The closure plate 3 and the closure plug 11 with the gripping tab 13 are made from the same plastic material.
In accordance with a second embodiment of the invention, the closure element for a through-opening 10 in a closure plate bottom 5 can be pivotably formed via a resilient bridge of plastic upon a section of its periphery that is on the bottom of the closure plate. In this case, the closure element cannot be lost and represents a common component with the closure plate.
The second object of the invention will now be described according to the preferred embodiment shown in FIGS. 3 and 4. The reservoir 101 shown in FIG. 3 has a bottom 103 and a neck area 102, on the outside of which a thread 104 has been cut. As seen in FIG. 4, a closure cap 110 also can be screwed on the neck.
An insert 105 has been clampingly placed in the neck area 102. A through-opening 108 is located on one side of it, while a wall adjoins the other side, which extends as far as the peripheral wall of the insert 105. A connector 107 extends upwardly through it. The central opening of the connector 107 extends through the wall. A conduit segment 109, perhaps in the shape of a hose, is fastened on the underside of the connector 107. The upper area of the conduit segment 109 extends coaxially with the central axis of the connector 107. In its lower area it is obliquely disposed, so that its lower end rests slantingly on the bottom 103. Because of this, the opening provided on the lower end of the conduit segment 109 is always located above the bottom 103. Preferably the conduit segment 109 forms a capillary conduit, in which the writing fluid always is close to the connector 107.
The exterior shape of the connector 107 has been selected to be such that it can be sealingly placed on a converter 115 with its opening. The converter customarily has an orifice which is embodied corresponding to the orifice of a so-called Euro ink cartridge.
To fill the converter 115, the screw cap 110 is removed from the reservoir 101, and the converter 115, with its piston moved into the front position, is placed on the connector 107. Writing fluid, customarily ink, is aspirated into the converter 115 via the conduit segment 109. The creation of underpressure in the reservoir 101 in the course of this is prevented by the opening 108 in the insert 105 of the reservoir 101. Because the conduit segment 109 extends proximate to the bottom 103, it is assured that the reservoir 101 can be practically completely emptied via the conduit segment 109.
It should be mentioned, of course, that it also is possible to fill a fountain pen through the opening 108. Thus, the reservoir 101 can be used additionally as a customary ink bottle. However, the opening 108 also may be closed off by means of a semi-permeable membrane, which is permeable to air and impermeable to fluid.
While the present invention has been described with respect to what presently are considered to be the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
|
A device for filling a converter with writing fluid, including a connector designed to be sealingly engaged with the orifice of a converter. The connector has an orifice in the shape of an orifice of a conventional ink cartridge. The device also includes a pipe-shaped conduit segment, connecting to the connector and extending into the interior of a reservoir containing writing fluid. The pipe-shaped conduit segment extends from the connector in an inclined fashion to a free end proximate to the bottom of the reservoir.
| 1
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority from U.S. Provisional Application Ser. No. 60/796,457, filed May 1, 2006.
BACKGROUND OF THE INVENTION
Foam buffing and finishing pads are typically made from a polymeric foam material, such as open cell polyurethane foam.
Conventional foam pads have tendency to absorb the water or petroleum-based polish or compound that is used in conjunction with the foam pad to accomplish the task of defect removal from painted and non-painted surfaces. This absorption creates a less effective working surface because the polish, which has abrasives in it, is not on the surface where it needs to be to accomplish the finishing task most efficiently.
Migrating water or petroleum-based polish or compound can penetrate the entire buffing pad and reach all the way to the rear attachment face. Here the compound can collect and, in addition to being messy, can clog the hook-and-loop fastening systems by which the pad is attached to the rotary or orbital driving device. It has been found that prior art pad mounting mechanisms do not adequately inhibit the penetration of moisture to the pad attachment face and the attachment device being used.
SUMMARY OF THE INVENTION
In accordance with the present invention, the operating face of a foam buffing, polishing or finishing pad is formed with random or strategically placed areas of partially collapsed foam cell structures. The pads are typically made to be rotary driven by a powered driving device. Rotary operation is intended to include the motion provided by orbital and dual action driving devices. In another embodiment, the rear attachment face of the pad may be similarly treated, but preferably the cells are fully collapsed causing a glazing or felting of the surface. The treated areas create depressions as a result of the collapse of the cells. With a partially collapsed cell structure, the cells are compressed, but still open to some extent. When the cells are fully collapsed, the cells at the surface are completely closed and the surface is virtually impervious. In other words, the surface is fully glazed over or “felted”, a term commonly used in the industry.
Adding random or specific depressions of partially collapsed cell structures to the operating face of the pad has several advantages over conventional, well known foam pads, namely, depressions of collapsed cell structures will slow down the rate of polish or compound absorption, thereby increasing the effectiveness of the polish or compound, and at the same time, saving the end user money by not requiring as much polish to perform the task; depressions of collapsed cell structures will break surface tension that constant full faced pads present, lessening the frequency of pad skipping; depressions of collapsed cell structures provide areas for debris commonly found on working surface to collect, thereby presenting a foam pad that will scratch less; depressions of collapsed cell structures, with less surface-to-surface contact, will reduce surface friction, thereby creating less heat which can damage the working surface; depressions of collapsed cell structures can aid in advertising by imprinting a client's logo or name in the surface of pad; and, depressions of collapsed cell structures are not limited to any shape, size or pattern. Specific shapes, depths and patterns will change the performance of the pad.
The depressions of partially collapsed cell structures can be provided in a random orientation or strategically placed on the operating face of the pad. By strategically placing these patterns, as indicated above, advertising or other indicia can be placed on the operating surface of the pad.
The method of the present invention can also be applied to form an impervious surface of fully collapsed cell structures on the rear attachment face of the pad to prevent or substantially preclude the migration of moisture or other carrier liquid all the way through the pad from the front working face.
In accordance with one embodiment of the method of the present invention, the front operating face of a surface finishing pad made of a cellular polymeric foam material is modified by (1) pressing a heated die face having a pattern of protrusions against the operating face to form depressions in selected areas of the operating face, and (2) holding the heated die in contact with the depressions for a time sufficient to cause the cells of the foam material to partially collapse and retain the depressions. The depressions may be formed in a pattern selected to provide a visually perceptible indicia or in a random pattern. A preferred polymer foam material is open cell polyurethane.
In another embodiment of the present invention, the rear attachment face of a surface finishing pad, using the same or a similar cellular polymer foam material, can be modified by applying the steps of (1) forming a generally planar attachment face on the pad, and (2) heating the attachment face to a temperature and for a time that is sufficient to cause the cells of a part or all of the rear attachment face to collapse, glaze over and form a liquid-impervious surface. The method may include the step of selecting an area on the attachment face that corresponds to the area of a loop scrim connecting piece, and heating the selected area. The method may also include the step of bonding the connecting piece to the selected area on the attachment face. The bonding step preferably comprises heat bonding. In the step of forming the planar attachment face, the attachment face may be depressed to form a recessed face.
In a further embodiment of the present invention, the front operating face and a generally planar rear attachment face of a surface finishing pad may be modified together using the steps of (1) providing a heated die having opposed front and rear halves to engage the respective faces of the pad with the front die half having a pattern of protrusions positioned to engage the front face and the rear mold half having a single planar face adapted to engage the rear pad face, (2) pressing the mold halves against the pad to form a pattern of depressions in the front face and planar contact with the rear face, (3) heating while pressing the protrusions in the pattern to a temperature sufficient to fix the depressions and (4) heating while pressing the single planar die face to a temperature sufficient to cause the cells of the foam material at the surface of the depression to collapse and glaze over, and cause the cells of the foam material at the surface of the depressions to partially collapse. In this method, the heating step is preferably sufficient to provide a surface in the planar face that is impervious to moisture. The method may also include the steps of (1) placing a connecting piece between the rear face of the pad and the rear mold half, and (2) causing the piece to adhere to the surface of the planar rear face.
In accordance with another embodiment of the present invention, a rotary surface finishing pad is made of a cellular polymeric foam material having an operating face and includes depressions that are formed in selected areas of a pad operating face, and the surfaces of the depressions have cells of the foam material that are partially collapsed. In this surface finishing pad, the depressions may be formed in a pattern selected to provide a visually perceptible indicia or formed in a random pattern. The polymeric foam material preferably comprises open cell polyurethane.
In a further embodiment, a rotary surface finishing pad has a generally planar attachment face which face is characterized by having the cells at the surface of the attachment face collapsed and glazed over to form a liquid-impervious surface. The pad may include an area on the attachment face for receipt of a loop scrim connecting piece, and the attachment face is thermoformed. The connecting piece is bonded to the attachment face, the bond preferably comprising a thermal bond. The attachment face is preferably recessed.
In particularly useful embodiment of the rotary surface finishing pad of the present invention, the pad has a front operating face and a generally planar rear attachment face, and the pad further comprises pattern of depressions in the front face and a single planar depression in the rear pad face, the cells at the surfaces of the depressions in the front face being partially collapsed and the cells at the surface of the rear face being collapsed and glazed over. The surface finishing pad of this embodiment preferably includes a rear attachment face that is impervious to moisture. The rear attachment face may be provided with a connecting piece. The front operating face of the pad may be planar or curved. The rear attachment face may be recessed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a generally schematic representation of the face of a die half in which a buffing pad of the present invention may be formed.
FIG. 2 is a perspective view of a buffing pad formed in the die of FIG. 1 .
FIG. 3 is a cross section through a two-part forming die showing a buffing pad of the present invention formed with a typical composite construction.
FIG. 4 is a cross section of the pad shown in FIG. 3 .
FIG. 5 is a cross section through a two-part forming die showing a buffing pad also having the rear attachment face formed in accordance with another embodiment of the invention.
FIG. 6 is a cross section through the pad shown in FIG. 5 .
FIG. 7 is a cross section of the pad shown in FIG. 6 after the peripheral edges are rounded.
FIG. 8 is a cross section view similar to FIG. 6 showing the compression of the pad operating face in use.
FIG. 9 is an enlarged detail taken on line 9 - 9 of FIG. 8 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring initially to FIGS. 2 and 4 , a buffing, polishing or finishing pad 10 is formed from a sheet of polyurethane foam. As is generally well known in the art, the pad 10 is a composite of a foam body 11 , having a front operating face 12 and a rear attachment face 13 comprising a sheet of loop scrim 14 attached by heat sealing to the rear face 13 by an intermediate sheet of polyethylene 15 .
The die from which the pad is formed includes a front die half 16 ( FIG. 1 ) having a recessed interior surrounded by a peripheral knife edge 17 to cut the foam body from a sheet of polyurethane foam. A rear die half 18 may include a slightly convex protruding surface 19 that forms a shallow dished rear attachment face 13 on the pad 10 . The attachment face could also be flat or planar. The loop scrim 14 on the rear face 13 is intended to be attached to a hook scrim sheet (not shown) comprising the other half of a conventional hook and loop fastening system. The hook scrim sheet is typically mounted on a rigid or semi-rigid backing plate attached to and driven by a rotary or an orbital drive apparatus. In the pad treating process of the present invention, one or both of the die halves 16 and 18 may be heated to a temperature to soften the polyethylene sheet 15 sufficiently to securely attach the loop scrim 14 to the rear face 13 of the pad body 11 . However, the foam body 11 cannot be heated so high as to cause the operating face 12 to glaze over (or “felt”) and seal the open cell structure.
In accordance with one embodiment of the present invention, the front die half 16 is provided with upstanding protrusions 20 which penetrate into the foam body 11 in the treating process to form depressions 21 in the operating face 12 of the pad. The die including the protrusions 20 is heated to a sufficient temperature to cause the cell structure of the foam surfaces in contact with the protrusions to partially collapse, yet still define a somewhat open, but more restricted cell structure on the surfaces 22 of the depressions. The temperature to which the front die half 16 is heated is low enough to prevent cell collapse of the surface defining the operating face 12 . However, because of the increased pressure with which the protrusions penetrate into the foam body, if the die half 16 is held at temperature for a sufficient time, the foam cells in the surfaces of the depressions 21 will partially collapse. Preferably, however, the surfaces of the recesses 21 are not permitted to completely glaze over and become impervious.
The protrusions 20 and depressions 21 formed by the protrusions are of cylindrical shape, but any convenient shape may be utilized. Also, the size of the depressions 21 can be varied considerably. In addition, the protrusions 20 may be arranged in a pattern that spells a name, message or other indicia in the operating face 12 of the pad. Such strategically placed indicia will still permit the pad to function to provide the desired result as summarized above.
A multi-cavity die can be used to form multiple pads at one time. In addition, pads with other types of backing material different than the loop scrim 14 may also be used. The polyethylene sealing sheet 15 , though preferable, can also be made of other materials.
In an alternate method for making finishing pads utilizing the features of this invention, the depressions 21 of collapsed foam cell structures may be formed in a large sheet of foam. The depressions 21 may be formed randomly or in a specific, strategically placed pattern, as indicated above. The foam pads 10 may then be cut or stamped from the sheet, using any convenient method known in the art. The required backing materials are then affixed to the rear face of the pads in the same manner indicated above.
The pad 10 shown in FIG. 4 is cut in the die half 16 as a generally cylindrical edge face 29 . If desired, in a subsequent operation, the edge face 29 may be cut or abraded away to form a rounded outer edge 30 as shown. Alternately, in an embodiment not shown, the pad could be provided with a curved operating face by using a curved die having a curved front half and a correspondingly curved rear half to shape and attach the polyethylene sheet 15 .
In accordance with another embodiment of the invention, as is shown in FIGS. 5 and 6 , the rear attachment face 13 of the foam body 11 has at least a portion of the attachment face treated to cause an area or areas of fully collapsed cell structures, resulting in a surface that is glazed over and impervious to the migration of moisture or other liquid. It is well known that open cell polymeric foam pads absorb water (or petroleum solvent) from the finishing compound being used. The moisture may migrate all the way to the rear face of the pad and may carry with it microfine particles of finishing compound. The result is that the layer of loop scrim 14 and the corresponding sheet of hook scrim (not shown) become wet and contaminated with finishing compound. The result is not only messy, but may interfere with proper attachment of the pad to the rotary driver. The polyethylene sheet 15 by which the loop scrim 14 is attached to the rear face 13 of the pad is not generally impervious to moisture and will not prevent the migration of moisture past that layer.
However, it has been found that by heating the rear attachment face 13 of the pad to a high enough temperature and for a sufficient time, the cell structure on the rear attachment face can also be caused to collapse and glaze over. If properly treated, the glazed rear face 23 can be made completely impervious to the migration of moisture and finishing compound.
Referring particularly to FIG. 5 , the glazed rear face 23 may be most conveniently formed in the die and, simultaneously, the rear face of the pad may be formed with the desired shallow depression 24 having a generally planar attachment face 25 . The peripheral edge 26 of the pad is turned up and permanently formed to surround the edge of the backing plate (not shown) when the pad is being used. This turned up edge protects the surface being finishing from contact with the hard edge of the backing plate.
As shown in FIG. 6 , the pad 10 may be formed with partially collapsed cell structures on the surfaces 22 in the depressions 21 of the operating face 12 and the glazed rear face 23 on the rear attachment face 13 . With common types of open cell polyurethane foam, a treating temperature in the range of about 345° F. to 450° F. applied for about 8 to 20 seconds, is sufficient to form impervious or semi-pervious glazed surfaces. With the wide variety of polymeric foam types available, treatment temperatures and times will vary considerably.
There are a number of benefits in treating the front operating face 12 of the pad to provide depressed areas of partially collapsed cell structures, as briefly discussed above. The partially collapsed cells on the surfaces 22 of the depressions 21 result in cell structures that are smaller than the fully open cells of the untreated foam material, but the cells are still open to some extent. As a result, the surfaces 22 of partially collapsed cells slow the rate of absorption of finishing compound into the pad. Finishing compound is thus held in the pockets or depressions 21 where it can continue to be available for the finishing task.
Because the partially collapsed cells at the surfaces of the depressions 21 are harder than the untreated foam of the remainder of the pad, the partially collapsed cell surfaces 22 could scratch the surface being finished. However, referring particularly to FIG. 7 , it has been found that, in use, as the pad face 12 is pressed against the surface 27 being finished, the softer foam surrounding the depressions 21 tends to be forced around the depressions, as shown at 28 . As a result, the harder and stiffer surfaces 22 of collapsed cell structures actually recede into the body 11 of the pad, as also shown in FIG. 7 . However, the depressions do not become closed off and, as a result, the finishing compound carried in the recesses remains available for the finishing operation and, because surfaces 22 of the depressions are more impervious, absorption of finishing compound into the foam body is reduced.
By comparison, a well known polyurethane foam finishing pad has a convoluted surface, but of uniform cell structure. The convolutions theoretically provide pockets in which finishing compound may be retained to enhance the finishing process. However, these pads have a uniform open cell structure and the operating face of the pad actually flattens completely against the surface being worked on as pressure is applied to the pad. In addition, completely open cell structure does not inhibit the migration of finishing compound into the pad. The pad of the subject invention, as shown in FIG. 8 , will not completely flatten when pressed against the surface 27 being worked on and will hold the polish or other finishing compound in the depressions 21 where it is continuously available for its intended purpose.
|
Selected surfaces of a cellular polymeric foam surface finishing pad are heated to cause the surface cells to partially collapse or to fully collapse and glaze over. The selected surfaces may be the planar pad faces or may be formed in one or more depressions formed in the planar faces. The areas of partially collapsed cell structures in the operating face of the pad provide a slow down in the rate of polish or compound absorption, increasing the effectiveness of the finishing process. The fully collapsed cell glazed surface on the rear attachment face of the pad prevents the migration of moisture through the pad to the pad attachment mechanism.
| 1
|
[0001] This is a continuation-in-part of U.S. application Ser. No. 12/832,749 filed Jul. 8, 2010 which is a continuation-in-part of U.S. application Ser. No. 12/390,095 filed Feb. 20, 2009 and claims the benefit thereof which claims benefit of U.S. Ser. No. 61/128,839 filed May 27, 2008.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to paint brushes and, more particularly, to a paint brush protective cover that protects the bristles of paint brushes from being damaged during wet or dry storage or nonuse thereby extending the life of the paint brush.
[0004] 2. Related Art
[0005] In cases where a purchaser opts to purchase a paint brush to perform a painting job, there is a choice of brush shape, size and different filament materials. A professional painter can own many brushes, each with its own use. Typically each project can require several brushes, for large areas a 3 or 4 inch is used for general cutting in large pieces or general use whereas and for trim a 1½ inch works well. On a professional site there may be a crew of painters each using several brushes.
[0006] Fine paint brushes are expensive however they are required for a professional job as they apply a smoother finish with less brush strokes and paint faster and with less effort. If properly cleaned and stored they will last for years and conversely if not will have a short life. Inexpensive paint brushes can shed bristles into the finish and are difficult to work with, producing an inferior finish.
[0007] Paint brushes are categorized according to the type of coating being applied; water based paints and primers, such as latex or acrylic paints and primer plus water based epoxy; oil based paints and primers, such as alkyd paints and primers plus oil based epoxies; solvent thinned paints and primers; water based clear wood finishes and stains, such as acrylic urethane, water based polyurethane and its variants plus water based wood stains; oil based clear wood finishes and stains; this includes the common varnish and polyurethane plus oil based wood stains; all solvent thinned clear finishes and wood stains; shellac primers and clear finishes, such as tinted and clear shellac is thinned with denatured alcohol.
[0008] Each of these “types” of coatings or stains has a specific type of brush that is used. Type of paint brush refers to the filaments used in its construction. These filaments can be synthetic, natural, or a combination of the two. Synthetic refers to different types of plastics used to make the filaments, nylon and polyester or blends of the two. Natural refers to animal hair that is used in the brushes construction, this type of filaments are called bristles. Filaments are designed for specific solvents and will be damaged if used in the wrong solvent or improperly stored.
[0009] Synthetic brushes loose there shape in oil base paints and primers, an oil paint brush must be stiff enough to hold its shape and soft enough not to leave to many brush marks. Brush manufactures use a blend of different natural bristles to change the softness and stiffness for performing a job, for example, one having the stiffness for cutting in a straight line and thicker hair for holding more paint or one suited for varnishes, polyurethane and stains or one's for clear wood finishes require a very soft brush for the best results.
[0010] Bristle brushes cannot be used with latex paints or be cleaned with water this will ruin the brush. Natural bristle paint brushes absorb water and loose their shape, becoming impossible to control. However, cleaning the brush after every use is not desirable as it takes time and use of costly solvents.
[0011] It is desirable to leave the brush wet. Some painters leave the brush in a zip lock bag or in a bucket of paint. While this prevents cleanup, it often results in the disfigurement of the bristles. This is particularly problematic with cut-in brushes which come in a variety of shapes such as angular, flat, and oval, and size ranges from 1-6 inches wide and if disfigured become useless.
[0012] Fine paint brushes typically are expensive. User's of fine paint brushes, such as professionals, require excellent coverage from their paint brush, durability from their paint brush, greater efficiency in production, precise lines, proven results for smooth finishes and a lack of bristles or filaments left behind from the paint brush. When a paint brush no longer is capable of producing, the paint brush will be discarded and a new paint brush is purchased to replace the old paint brush.
[0013] After a job is finished, the brush must be cleaned in an appropriate solution to remove all of the remaining paint. Sometimes the bristles tend to separate and fray off in non-uniform directions and become a problem for the next usage so care must be taken to store the brush in a manner wherein the bristles can be maintained aligned.
[0014] Covers that the paint brushes are sold in are made of paper and are rather flimsy and easily tear and do not last very long. If no protective cover is used, in addition to the above described disfigurement occurring, dust and other particles generally stick and become imbedded inside the bristles. These particles will collect on the paint producing non-uniform streaks of paint during use.
[0015] Prior attempts to cover paint brushes include conventional paper or plastic covers which substantially fold about the bristles to maintain the filament shape. Some cases provide for air holes so that the filaments can dry after cleaning is performed.
[0016] The problem which is not addressed is that of wet media storage. Painters need a simple and easy cover for both dry and wet storage of the brushes which protects the filaments. There is also a need for quick, safe and easy transportation of brushes. Therefore, a need exists to provide an improved paint brush protective cover. The improved paint brush cover must be simple to use, allow for wet and dry storage, easy cleanup and durability and be inexpensive.
SUMMARY OF THE INVENTION
[0017] It is an object to improve paint brush covers.
[0018] It is a further object to provide a wet/dry paint brush cover.
[0019] It is another object to provide an improved paint brush protective cover that is simple to use.
[0020] Yet another object is to provide an improved paint brush protective cover that is durable.
[0021] It is another object to provide an improved paint brush protective cover that is inexpensive.
[0022] Still another object is to provide safe and easy transport of a paint brush.
[0023] A further object is to provide a user with a productivity guide for the brush.
[0024] Another object is to enable storage of a brush in wet media.
[0025] Accordingly, one embodiment of the invention is directed to a paint brush protective cover for a paint brush having filaments, a collar retaining the filaments and handle. The brush cover which includes a jacket having a hollow interior section, wherein the jacket has a first panel and a second panel removably connectable to the first panel in a manner to be maintained in a predetermined spaced relation to receive the paint brush therebetween, wherein each panel has an upper end and a lower end and are configured to be complementary connected in a manner with the upper ends adjacent one another and the lower ends adjacent one another, wherein the jacket is of a length greater than a combined length of filaments and at least the collar and the upper ends are configured to retain about the collar and said lower ends are configured to retain about the filaments, and wherein the jacket includes at least one lower opening adjacent a terminal part of the lower ends to readily permit drainage from said jacket by virtue of gravity when upper ends are further displaced from a gravitational surface than the lower ends; and wherein each the panel includes at least one panel opening which extends lengthwise from each the upper end into the lower end terminating at a predetermined distance from a lower end edge and is defined by top edge, bottom edge and side edges, and at least one productivity guide and wear bar which extends transversely through the panel opening and interconnecting the side edges to retain filaments of the brush and serves as a visual productivity guide and wear indicator for filament length. The panels are further equipped with transverse ribs which extend across the upper ends. Side ribs are also provided which extend lengthwise along outer edges of each panel. The lower ends are connected by a junction panel which includes spaced openings to provide drainage yet maintain rigidity and structure.
[0026] Another embodiment is directed to a paint brush protective cover for a paint brush having filaments, a collar or ferrule retaining the filaments, which includes a jacket having a hollow interior section, wherein the jacket has a first panel and a second panel removably connectable to the first panel in a manner to be maintained in a predetermined spaced relation to receive the paint brush therebetween, wherein each the panel has an upper end and a lower end and are configured to be complementary connected in a manner with the upper ends adjacent one another and the lower ends adjacent one another, preferably by living hinge, wherein the jacket is of a length greater than a combined length of filaments and at least the collar and the upper ends are configured to retain about the collar and the lower ends are configured to retain about the filaments, and wherein the jacket includes at least one lower opening adjacent a terminal part of the lower ends to readily permit drainage from the jacket by virtue of gravity when upper ends are further displaced from a gravitational surface than the lower ends; and wherein each panel includes at least one panel opening which extends lengthwise from each the upper end into the lower end terminating at a predetermined distance from a lower end edge and is defined by top edge, bottom edge and side edges, and at least one productivity guide and wear bar which extends transversely through the panel opening and interconnecting the side edges to retain filaments of the brush and serves as a visual productivity guide and wear indicator for filament length.
[0027] Still another embodiment is directed to a paint brush protective cover for a paint brush having filaments, a collar retaining the filaments and handle. The cover includes a jacket having a hollow interior section, wherein the jacket has a first panel having lateral connecting surfaces and a second panel having lateral connecting surfaces configured to receive the lateral connecting surfaces of said first panel in a manner to removably connect the first panel and the second panel in a manner to be maintained in a predetermined spaced relation to receive the paint brush therebetween. Each panel has an upper end and a lower end and are configured to be complementary connected in a manner with the upper ends adjacent one another and the lower ends adjacent one another, wherein the jacket is of a length greater than a combined length of filaments and at least the collar and the upper ends are configured to retain about the collar and the lower ends are configured to retain about the filaments, and wherein the jacket includes at least one lower opening adjacent a terminal part of the lower ends to readily permit drainage from the jacket by virtue of gravity when upper ends are further displaced from a gravitational surface than the lower ends; and wherein each the panel includes at least one panel opening which extends lengthwise from each the upper end into the lower end terminating at a predetermined distance from a lower end edge and is defined by top edge, bottom edge and side edges, and at least one productivity guide and wear bar which extends transversely through the panel opening and interconnecting the side edges to retain filaments of the brush and serves as a visual productivity guide and wear indicator for filament length. The lower openings on the jacket allow fluid such as paint and solvent to drain adequately and the openings allow air to circulate within the protective cover and about the filaments of the brush.
[0028] The invention provides a protective measure for the filaments as well as productivity guide and wear indicator of for the filaments. This deters the filaments from becoming disfigured. Also, the productivity guide and wear bar aids in showing the amount of usage left on the brush.
[0029] A handle opening is formed in end surface of the jacket adjacent the upper ends of the panels allowing the handle of the paint brush to protrude out of the jacket. The handle opening is formed between laterally extending connecting surfaces of each of the first and second panels which provide connection of the panels as well as the panels all of which serve to retain about the handle. The first panel's lateral connecting surfaces can be configured to be received inside of the second panel's lateral connecting surfaces and can include a detent surface or other friction fit surface to maintain connection therebetween. A laterally extending tab can be provided on the first panel to aid in separating the panels once connected.
[0030] The foregoing and other objects, features, and advantages of the invention will be apparent from the following, more particular, and description of the preferred embodiments of the invention, as illustrated in the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, as well as a preferred mode of use, and advantages thereof, will best be understood by reference to the following detailed description of illustrated embodiments when read in conjunction with the accompanying drawings.
[0032] FIG. 1 is an elevated perspective view of the paint brush protective cover of the present invention in a closed position covering the bristles of a paint brush disposed within a paint container with wet media (paint) therein for wet media storage.
[0033] FIG. 2 is an elevated perspective view of the paint brush protective cover of the present invention in a closed position.
[0034] FIG. 3 is a perspective view of the paint brush protective cover of the present invention in an open position showing an interior thereof.
[0035] FIG. 4 is a perspective view of the paint brush protective cover of the present invention in an open position showing an exterior thereof.
[0036] FIG. 5 is a back outside plan view of the paint brush protective cover of the present invention in an open position.
[0037] FIG. 6 is a side view of the paint brush protective cover of the present invention in an open position.
[0038] FIG. 7 is an end view of the paint brush protective cover of the present invention in an open position.
[0039] FIG. 8 is a front inside plan view of the paint brush protective cover of the present invention in an open position.
[0040] FIG. 9 is an enlarged view of a living hinge portion of FIG. 6 .
[0041] FIG. 10 is an enlarged view of a portion of FIG. 5 .
[0042] FIG. 11 is an enlarged view of another portion of FIG. 5 .
[0043] FIG. 12 is a plan back view of an embodiment of the invention.
[0044] FIG. 13 is an enlarged view of a portion of FIG. 12 .
[0045] FIG. 14 is an enlarged view of another portion of FIG. 12 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0046] Referring now to the drawings, a paint brush protective cover is generally designated by the numeral 10 . The paint brush protective cover 10 includes a single jacket 12 made from an anti-stick polymer plastic, such as polystyrene, so that paint will not readily adhere to the jacket 12 . This will aid in the wet storage aspect of the invention.
[0047] The jacket 12 can be rectangular in shape and it is contemplated that the jacket 12 can be configured with various shapes and sizes so long as the objectives of the invention can be maintained. The jacket 12 should be sufficient enough size to contain a lower end 13 of the paint brush 14 and at least part of an upper end 15 of the paint brush 14 . By way of example, the jacket 12 is configured for a 2″ brush 14 .
[0048] The jacket 12 has a hollow interior section 16 which is defined by a first panel 18 and a second panel 20 of the jacket 12 which are removably connectable to one another in a manner to be maintained in a predetermined spaced relation. Each panel 18 and 20 has an upper end 22 and 24 , respectively, and a lower end 26 and 28 , respectively, which are configured to be complementary connected in a manner with the upper ends 22 and 24 adjacent one another and the lower ends 26 and 28 adjacent one another. Each panel 18 and 20 have transverse exterior ribs 21 and 23 respectively which here are shown as rectangular ribs across upper ends 22 and 24 respectively.
[0049] The first panel 18 includes lateral connecting surfaces 30 A and 30 B and can be configured to be received inside of the second panel 20 lateral connecting surfaces 32 A and 32 B. The end 24 includes a retaining member 25 which together with connecting surfaces 32 A and 32 B provide a receiving area for connecting surfaces 30 A and 30 B. By way of example, lateral connecting surfaces 30 A and 30 B fit within retaining members 25 and surfaces 31 A and 31 B or other friction fit surface to improve connection with connecting surfaces 32 A and 32 B. A laterally extending tab 34 can be provided on the first panel 18 to aid in separating the panels 18 and 20 once connected.
[0050] The jacket panels 18 and 20 are of a length greater than a combined length of filaments and at least a collar part of the paint brush retaining the filaments and preferably a greater than a combined length of filaments (herein referred to as lower end 13 of the brush 14 ), and collar part of the paint brush retaining the filaments and part of the handle (herein referred to as upper part 15 of the brush 14 ).
[0051] Upper ends 22 and 24 are configured to retain about the upper part 15 of the brush 14 and lower ends 26 and 26 are configured to retain about lower end 13 of the brush 15 . Each panel 18 and 20 can include a plurality of laterally spaced elongated openings 36 and 38 , respectively, which extend from respective upper ends 22 and 24 , respectively, and into the lower ends 26 and 28 , respectively, terminating at a predetermined distance “X” short of an edge 40 and 42 of each panel 18 and 20 , respectively. In this regard, it is important to note that the openings 36 and 38 can preferably not extend to a point beyond the length “L” of the filaments of the brush when stored within the jacket as this could permit the filaments to become disfigured by protruding outside of the openings 36 or 38 .
[0052] Productivity guide and wear bars 27 and 29 are provided. Openings 36 and 38 extend lengthwise from each the respective upper ends 22 and 24 into the lower ends 26 and 28 respectively terminating at a predetermined distance from a lower end edge 40 and 42 , respectively, and are defined by top edge 60 and 62 , bottom edge 64 and 66 , respectively, and side edges 68 and 70 , respectively. Productivity guide and wear bars 27 and 29 extend across the respective panels 18 and 20 transversely through the panel openings 36 and 38 , respectively, and interconnect the side edges to retain filaments of the brush and serves as a visual productivity guide and wear indicator for filament length as well as lend rigidity and strength to the cover 10 .
[0053] The productivity guide and wear bars 27 and 29 aid in retaining the filaments 13 of the brush 14 . The productivity guide and wear bars 27 and 29 can preferably include a curved rib cross section which aid in guiding the filaments 13 , broken and unbroken, into the jacket 12 . The productivity guide and wear bars 27 and 29 provide a good visual indication of the productivity remaining of the brush 14 and aid in retaining filaments 13 within the jacket 12 .
[0054] Accordingly, each lower end 26 and 28 of each panel 18 and 20 , respectively, there remains a continuous transverse section to retain the filaments and into which the openings 36 and 38 do not extend. The plurality of openings 36 and 38 are thus located on the jacket 12 for allowing fluid such as paint, solvent, or air to circulate within the protective cover and about the filaments of the brush 14 .
[0055] A handle opening 44 is formed in end surface 23 of the jacket 12 adjacent the upper ends 22 and 24 of the panels 18 and 20 allowing the handle H of the paint brush to protrude out of the jacket 12 . The handle opening 44 is formed between laterally extending connecting surfaces 30 A, 30 B and 32 A, 32 B and ends 22 and 24 of each of the first and second panels 18 and 20 all of which serve to retain about the handle H. Sides 32 A and 32 B do not extend the panel 20 to permit flow of paint out of the end of the jacket 12 when closed.
[0056] One may open the jacket 12 to expose a hollow interior section 16 . The interior section 16 is where the bristles of the paint brush 14 will be stored in wet or dry manner. The first panel 18 is connected together the second panel by a junction panel 50 and is characterized as a living hinge which is a special type of connector style that is bent while the plastic piece is still warm right out of the mold. Junction panel 50 includes a plurality of lower spaced openings 41 to readily permit drainage and which are separated by transverse portions 43 of panel 50 . Opening the jacket 12 will expose the hollow interior section 16 enabling positioning the paint brush 14 within the jacket 12 and when closed protect the bristle or filament 13 configuration of the brush 14 .
[0057] The openings 36 and 38 provide for retention of the bristles while being stored in paint in the case of the jacket 12 being submerged into paint with the brush 14 therein as seen in FIG. 1 . Upon removal, these openings 36 and 38 provide for quick drainage of paint from the jacket 12 so that the jacket 12 can be readily opened without causing a paint spill. After removal of the brush 14 from the jacket 12 , any remaining paint on the jacket 12 should easily drip off. After a job, the brush 14 is cleaned and disposed back in the jacket 12 where the openings 36 and 38 will allow air to circulate therein. The air will allow the bristles of the paint brush 14 dry quickly after being cleaned and prevent mold and mildew from forming inside the jacket 12 .
[0058] The protective cover 10 can be preferably be molded such as by injection for example. In this way, the components herein described are integrally formed. While the application has made mention of a preferred use with professional paint brushes, it is conceived that the invention can be employed with various sized brushes, such as artist brushes or the like, wherein the protective cover 10 would be reduced in size to accomplish the intended goal of the invention.
[0059] While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.
|
A paint brush protective cover for a paint brush includes a jacket which provides for wet media storage and safe transportation.
| 0
|
FIELD OF THE INVENTION
The invention relates to a stop motion mechanism for textile machines for transmitting a signal for stopping a working station in case of a thread breakage or a used-up supply bobbin or otherwise exhausted thread and of the kind which includes a thread guide eyelet secured to a thread sensor bar which is pivotable about a horizontal pivot shaft.
BACKGROUND OF THE INVENTION
The usual stop motions of this kind (see e.g. German OS No. 20 24 122) have a relatively long thread sensor bar and, thus, a relatively long distance between the pivot shaft and the thread guide eyelet so that, depending on the distance from the pivot shaft, the vibrations which are transmitted from the running thread to the thread sensor bar, are effective in an intensified degree in the range of this pivot shaft. The resulting increased load in the range of the pivot shaft leads to damages to the shaft bearings. This, in turn, is of negative influence on the sensitivity of response of the stop motion e.g. in case of a thread breakage. This may result in the fact that the thread sensor bar, upon the occurence of a thread breakage, is delayed in its pivotal downward movement under the force of gravity, from its operational position in which it is maintained by the running thread, to a lower position thereby releasing a signal or a control command for stopping the work station.
The vibrations which are transmitted from the running thread to the thread sensor bar can have an extremely negative effect in case of a two-for-one twisting spindle in which the stop motion forms the thread guide eyelet defining the apex of the thread balloon. The momenta originating from the thread balloon act in axial direction of the balloon as well as perpendicularly thereto. Depending on the length of the thread sensor bar, they are transmitted to the pivot shaft bearings in an intensified degree.
SUMMARY OF THE INVENTION
The object of the invention is to improve a stop motion of the kind described above in such a way that the vibrational momenta, which are transmitted from the running thread to the thread sensor bar, are absorbed to such an extent that, in the range of the pivot shaft bearings, the existing forces are almost about nil in order to obtain substantial protection of the bearings against damages and the disadvantageous consequences resulting therefrom.
For solving the aforementioned problem, the novel stop motion is characterized by a guide element located between the pivot shaft and the thread guide eyelet, said guide element supporting the thread sensor bar in upward direction and against lateral vibrational movements.
In this way, the vibrational momenta coming from the thread balloon are absorbed by the guide element in front of the pivot shaft so that the shaft bearings are intensively protected against wear due to vibration.
In order to bring the pivot shaft of the thread sensor bar as close as possible to the thread guide eyelet, according to a further feature of the invention, the pivot shaft is journalled in a holding member secured to a holding rod and supporting the guide element, said holding rod being adapted to be secured to the machine frame.
Preferably, the guide element is exchangeably secured to the holding member. By exchanging the guide element, a damage and a resultant inaccuracy in the response of the stop motion can be counteracted also in view of processing yarns of different qualities.
Preferably, the holding member is in the form of a substantially shuttle-shaped housing provided with a removable cover lid in order to protect, as far as possible, the switching and actuating elements and also the pivot shaft of the stop motion, against external influences, particularly dust and fluff.
Preferably, the thread sensor bar is likewise exchangeably inserted in a swivel member which is pivotable about the pivot shaft so that the thread guide eyelet can also be exchanged in view of yarns of different qualities and of possible damages in the range of the thread guide eyelet.
Preferably, the thread sensor bar forms the first arm of a two-armed lever pivotable about the pivot shaft and including the swivel member whereby the second arm serves, on the other hand, for initiating the function of pneumatical, electrical or electro-magnetical and/or mechanical switching or actuating elements which are provided in the range of the holding member and are responsive to pivotal movements of the thread sensor bar.
The holding rod which carries the holding member and is adapted to be secured to the machine frame, is preferably formed as an air duct opening into a pressure nozzle within the housing forming the holding member. Preferably, in such embodiment, a swivel plate is arranged opposite to the free end of the second arm of the two-armed lever, said swivel plate supporting a sealing member for closing the pressure nozzle which is assigned to a switching mechanism for machine components adapted to be controlled by the stop motion.
Preferably, the guide element is arranged closely adjacent to the thread guide eyelet so that, in consequence of the reduced length of the lever arm between the thread guide eyelet and the guide element, the load acting on the latter is reduced as far as possible.
Preferably, the guide element is provided with a groove tapering from bottom to top, the width of said groove being adapted to the width of the thread sensor bar so that the latter, in its operational position with normally running thread, is supported against lateral and upwardly directed vibrational movements.
A further preferred embodiment of the invention is characterized by exchangeable bearing rings slipped on the pivot shaft and received in bearing seats.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further described, by way of example, with reference to the accompanying drawings in which:
FIG. 1 is an axial section of the stop motion according to the invention with the thread guide eyelet occupying its operational position (with normally running thread);
FIG. 2 is a sectional view corresponding to that of FIG. 1 with the thread guide eyelet pivoted downwardly (e.g. in case of a thread breakage);
FIG. 3 is a plan view of the stop motion according to the invention with the cover lid removed from the housing forming the holding member; and
FIG. 4 is a sectional view in the direction of the arrow IV--IV showing only the guide element and the swivel member carrying the thread sensor bar, together with the pivot shaft and the exchangeable bearing rings.
DETAILED DESCRIPTION OF THE INVENTION
The stop motion according to the invention comprises, as its essential components, a thread sensor bar 2 integral with a thread guide eyelet 3 which is formed as a pig tail, said thread sensor bar being pivotable about a pivot shaft 1, as well as a guide element 4 located between the pivot shaft 1 and the thread guide eyelet 3, and being provided with a groove 5 tapering from bottom to top. When the thread guide eyelet 3 and the thread sensor bar 2 occupy the position which is especially shown in FIGS. 1 and 4 and corresponds to the operational position with normally running thread, the thread sensor bar 2 is supported against lateral and upwardly directed movements by the side faces of the prism-shaped groove 5 tapering from bottom to top. In this way, the vibrational movements which are transmitted from a running thread to the thread guide eyelet 3 and, thus, to the thread sensor bar 2, are prevented from passing over to the pivot shaft 1 and its bearings, i.e., the vibrational movements acting on the pivot shaft 1, are reduced to a minimum value.
The thread sensor bar 2 is exchangeable and is inserted in a swivel member 6 pivotable about the pivot shaft 1, and is fastened therein e.g. by a screw (not shown), said swivel member 6 being substantially in the form of a two-armed lever, whereby the thread sensor bar 2 forms an extension of one of the lever arms. The pivot shaft 1 is inserted in the swivel member 6, and the bearing rings 7 are exchangeably slipped on the outwardly protruding ends of the pivot shaft 1.
The swivel member 6 is journalled, by means of bearing seats 8, in a substantially shuttle-shaped housing 9 forming a holding member, which housing is adapted to be closed against the environment by means of a cover lid 10. At its front end, the housing 9 is provided with an upper extension bonnet 11 into which the guide element 4 with its prism-shaped groove 5 facing downwardly, is exchangeably inserted and fastened therein e.g. by means of a screw (not shown). The cover lid 10 is fastened to the housing 9 in a manner not shown by means of a snap lock and is provided, on its underside, with a stop member 12 in order to limit the downwardly directed pivotal movement of the swivel member 6 as shown in FIG. 2. For this reason, swivel member 6 is likewise provided with a stop member 21.
The housing 9 is secured to a holding rod which is in the form of an air duct 13 by means of which the stop motion, as a whole, can be attached to the frame of a textile machine (not shown). The air duct 13 is adapted to be connected to a compressed-air source in the range of the machine frame.
The front end of the air duct 13 which extends into the housing 9, is formed as a pressure nozzle 14, the opening of which, in the position shown in FIG. 1, is closed by a swivel plate 15 carrying a sealing member 16. As shown in FIG. 1, the swivel plate 15 and the sealing member 16, respectively, are urged to and maintained in a position in which the pressure nozzle 14 is closed, by the rear arm of the swivel member 6 which is formed as a two-armed lever. The rear arm of the swivel member 6 and the swivel plate 15 are designed and coordinated in such a way that the pivotal movement of the thread guide eyelet from the operational position shown in FIG. 1 in which the thread guide eyelet is retained by the running thread, to its lower position subsequent to a thread breakage, is not obstructed or impeded. With respect to the distribution of weight, the swivel plate 15 which is pivotable about the axis 17, is designed so that it swivels in clockwise direction under the force of gravity as long as it is not urged, by the rear end of the swivel member 6, to the position for closing the pressure nozzle 14. The opening of the latter is therefore cleared.
A reed contact 18 is provided in the range of the rear arm of swivel member 6 which reed contact is connected, through a cable 19, to switching or actuating elements which are located e.g. in the area of the machine frame.
In order to actuate the reed contact 18, the rear arm of swivel member 6 carries a permanent magnet 20 which is positioned so that, depending on the pivotal position of the swivel member 6, the reed contact 18 is either opened or closed by means of said permanent magnet 20.
When the thread guide eyelet 3 occupies the operational position shown in FIG. 1, the pressure nozzle 14 is closed by the sealing member 16 which is inserted in the swivel plate 15, and the reed contact 18 is also closed. In this way, corresponding pneumatically and electrically controllable actuating elements are positioned or influenced in a manner which corresponds to the normal operation of the working station fitted with the stop motion according to the invention.
In case of a thread breakage or a used-up supply bobbin, the thread guide eyelet 3 tilts into the position shown in FIG. 2 since it is no longer supported by the thread whereby, on one hand, the opening of the pressure nozzle 14 is cleared in consequence of a pivotal movement of swivel plate 15 and the sealing member 16 associated therewith and whereby, on the other hand, the reed contact 18 is also opened. The resulting pressure-drop within the air duct 13 as well as the opening of the reed contact 19 result in the activation of succeeding control or actuating mechanisms so that the latter can take up their function and provide e.g. for the stoppage of the working station of the textile machine which is fitted with the stop motion.
In consequence of the pneumatical operation of the stop motion, compressed air will escape from the pressure nozzle 14 into the interior of the housing 9 upon any switching operation. Therefore, an excess pressure will forcibly build up in the housing. This excess pressure can escape only through the gap between the movable and stationary components of the entire stop motion which gap is due to construction. However, the escaping air will provide for the cleaning of the interior of the housing since any dust which has possibly been accumulated within the gap, will be prevented by the excess pressure from further penetrating into the housing.
In the drawings and specification there has been set forth a preferred embodiment of the invention and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.
|
A stop motion for textile machines for transmitting a signal for stopping a working station in case of a thread breakage or a used-up supply bobbin. The stop motion includes a thread guide eyelet secured to a thread sensor bar which is pivotable about a horizontal pivot shaft, and is characterized by a guide element located between the pivot shaft and the thread guide eyelet. The guide element supports the thread sensor bar in its normal operating position against lateral vibrational movements exerted by the running thread.
| 3
|
This application is a divisional of application Ser. No. 09/995,834, filed Nov. 29, 2001 now U.S. Pat. No. 6,517,728, which is a continuation of application Ser. No. 09/350,919, filed Jul. 12, 1999 now U.S. Pat. No. 6,346,200, which is a continuation of application Ser. No. 08/466,702, filed Jul. 13, 1995 now U. S. Pat. No. 5,958,254 which is a 371 of PCT/AU93/00598 filed Nov. 24, 1993.
FIELD OF THE INVENTION
This invention relates to compositions for reducing the oxygen concentration present in an atmosphere or liquid (often referred to as oxygen scavenging). In one particular application, the compositions are used in or in association with food packaging.
BACKGROUND OF THE INVENTION
A wide variety of foods and other materials are susceptible to loss in quality during storage under atmospheric levels of oxygen. The damage can arise from chemical oxidation of the product, from microbial growth, and from attack by vermin—much of which may be avoided by reducing the oxygen availability in the environment of the materials. In the field of packaging, relatively low-oxygen atmospheres have traditionally been generated by vacuum packing and inert gas flushing. Such methods are not, however, generally applicable for various reasons. For example:
soft porous foods such as cakes cannot be subjected to strong vacuum;
fast filling speeds generally preclude substantial evacuation of or thorough inert gas flushing of food packages;
filling some gas-flushed containers, such as beer bottles often results in occlusion of air;
evacuation or flushing offers no residual capacity for removal of oxygen, which may have desorbed from the food or entered the package by leakage or permeation.
As a consequence there has been much interest in chemical techniques for generating low-oxygen atmospheres and deoxygenating liquid or semi-liquid foods. Thus, there are approaches based on the use of oxidisable solids, for example porous sachets containing iron powder. In another technique, oxidisable MXD-6 Nylon is blended with polyester in the walls of blow-moulded containers—the effectiveness of this depends on the presence of a cobalt salt catalyst, moreover the speed of oxygen removal is limited by the oxygen permeability of the polyester. Further methods include sandwiching crystalline oxidisable material between the layers of multilayer containers, and including a catalyst for the reaction of oxygen with hydrogen in a sandwich arrangement as above or as a deposit on the inner surface of the package.
Heterogeneous systems such as described above do not, however, adequately meet the general needs of the packaging industry, largely because they are often oxygen-sensitive prior to use or can be activated only under restricted conditions of, for example, temperature or humidity. U.S. Pat. No. 5,211,875 proposes a composition intended to avoid the problem of oxygen-sensitivity prior to use, involving an oxidizable organic compound (typically 1,2-polybutadiene) and a transition metal catalyst (typically cobalt salt). Oxygen scavenging is initiated by exposing the composition to an electron beam, or ultraviolet or visible light.
However, the inclusion of a transition metal catalyst has a number of disadvantages including added cost, solubility difficulties, and a “gritty” appearance and reduced transparency of films made from such compositions. Some transition metal catalysts are also considered toxic and may not, therefore, be used with food.
The present invention avoids the disadvantages of including a transition metal catalyst. It may be based on plastic or other polymer-based compositions which can be activated as required, to effect reduction of ambient oxygen levels.
SUMMARY OF THE INVENTION
Accordingly, in a first aspect the present invention provides a composition for reducing the concentration of molecular oxygen present in an atmosphere or liquid, comprising at least one reducible organic compound which is reduced under predetermined conditions, the reduced form of the compound being oxidizable by molecular oxygen, wherein the reduction and/or subsequent oxidation of the organic compound occurs independent of the presence of a transition metal catalyst.
Preferably, the reduction and/or subsequent oxidation of the at least one reducible organic component is also independent of the presence of an alkali or acid catalyst.
The reducible organic compound for use in this invention may be reduced under predetermined conditions such as by exposure to light of a certain intensity or wavelength or, alternatively, by the application of heat, γ-irradiation, corona discharge or an electron beam. Possibly, also, the compound may be reduced by incorporating in the composition a reducing agent which in turn can be activated under predetermined conditions, say by heating.
DETAILED DESCRIPTION OF THE INVENTION
Typically the reducible organic compound will be a compound having the capacity to be converted to an excited state such as a triplet form, which then becomes reduced to an essentially stable state by gaining or abstracting an electron or hydrogen atom from other molecules or by redistributing an electron or hydrogen atom within the compound itself. The reduced molecule is reactive towards molecular oxygen to produce activated species such as hydrogen peroxide, hydroperoxy radical or a superoxide ion. Preferably, the reducible organic compound is stable in air at room temperature or is in its fully oxidized state. Examples of suitable compounds include quinones, such as benzoquinone, anthraquinone (preferably, 9,10-anthraquinone) and naphthoquinone (preferably, 1,4-napthoquinone); and photoreducible dyes and carbonyl compounds which have absorbance in the UV spectrum, such as azo, thiazine, indigoid and triarylmethane compounds.
Most preferably, the reducible organic compound is a substituted anthraquinone such as 2-methylanthraquinone and 2-ethylanthraquinone. In some applications, 2-ethylanthraquinone shall be preferred to 2-methylanthraquinone due to its greater solubility.
The reducible organic compound component may comprise 0.1-99.9 wt % of the composition. More preferably, the reducible organic compound comprises 0.1-50 wt % of the composition.
Compositions of this invention which involve the formation of an activated oxygen species (eg, peroxide) may further comprise a scavenging component reactive towards the activated species. This may be embodied in the reducible organic compound itself, for example a quinone having an amine group would be effective, but in any event it should be an agent which is substantially stable in contact with air at room temperature. Suitable examples of the activated oxygen scavenging component include antioxidants such as alkylated phenols and bisphenols, alkylidene bis-, tris- and polyphenols, thio- and bis-, tris- and polyalkylated phenols, phenol condensation products, amines, sulfur-containing esters, organic phosphines, organic phosphites, organic phosphates, hydroquinone and substituted hydroquinones; inorganic compounds such as sulphates, sulfites, phosphites and nitrites of metals, particularly those of groups 1 and 2 of the periodic table and first row transition metals, zinc and tin; sulfur-containing compounds such as thiodipropionic acid and its esters and salts, thio-bis(ethylene glycol β-aminocrotonate), as well as the amino acids cysteine, cystine and methionine; and nitrogen-containing compounds capable of reacting with activated forms of oxygen include primary, secondary and tertiary amines and their derivatives including polymers.
Preferably, the scavenging component reactive towards the activated oxygen species is selected from the group consisting of triphenylphosphine, triethylphosphite, triisoproppylphosphite, triphenylphosphite, tris(nonylphenyl) phosphite, tris(mixed mono- and bis-nonylphenyl) phosphite, butylated hydroxytoluene, butylated hydroxyanisole, tris(2,4-di-tert-butylphenyl) phosphite, dilaurylthiodiprpionate, 2,2-methylene-bis-(6-t-butyl-p-cresol), tetrakis(2,4-d-tert-butylphenyl)4,4′-biphenylene diphosphonite, poly(4-vinylpyridine) and mixtures thereof.
The activated oxygen species-scavenging component may be in the form of a polymer or oligomer. Such forms may be prepared by, for example, covalently bonding a compound such as those activated oxygen species-scavenging compounds listed above to a monomer or co-monomer. A limitation on the molecular size of the activated oxygen species-scavenging component will be the effect, if any, it has on functional properties of any other polymer with which it is combined as in blending for instance.
The activated oxygen species-scavenging component may comprise 0.1 to 99.9 wt %, more preferably, 0.1 to 50 wt % of the composition.
As an alternative to components which can be excited to a state which converts oxygen to an activated species, compositions according to this invention may comprise components which are excitable to a state in which they react and bind directly with oxygen diffusing into the composition from the surroundings.
The compositions according to the invention may further comprise an adhesive (eg, a polyurethane such as LAMAL) and/or a polymer. Preferred polymers are homogenous and include polyvinyls, polyolefins and polyesters or their copolymers, ethyl cellulose and cellulose acetate. Heterogeneous substrates, eg inorganic polymers such as silica gel or polymer mixtures may also be used.
Alternatively or additionally, the reducible organic compound itself maybe in a polymerised form either as homopolymers or copolymers. Oligomer forms may also be suitable. Reducible monomers can be made by covalently bonding an ethylenically unsaturated group to a reducible organic compound. The reducible organic compound may also carry groups capable of reaction with other polymerisable molecules and preformed polymers. Particular examples of ethylenically unsaturated reducible monomers include vinyl and isopropenyl derivatives, preferably bonded to the reducible organic compound in such a manner as not to decrease the lifetime of the triplet excited state compared with that of the unsubstituted reducible organic compound. Thus in the case of 9,10-anthraquinone substitution occurs preferably at the 2, 3, 6 or 7 positions. If such a reducible organic compound carries additionally further substituents besides the vinyl or isopropenyl group, such substituent should preferably be in one or more of the remaining preferred positions.
Co-monomers can be any ethylenically unsaturated substance whether mono-unsaturated, di-unsaturated or polyunsaturated. Examples include alkenes of carbon number two to eight, vinyl acetate, vinyl alcohol, acrylic monomers including methacrylic and acrylic acids, their amides, esters and metal salts as in ionomers, acrylonitrile, methacrylonitrile, norbornene, norbornadiene. If the reducible organic compound is a substituted 9,10-anthraquinone and is required to be difunctional monomer for formation of a polyester, the two carboxyl or hydroxyl substituents, or their derivatives should preferably be in any two of the positions, 2, 3, 6 or 7.
Reducible monomers may be polymerised as condensation polymers such as polyesters, including polycarbonates, polyamides, polyimides. An example of a polyamide is the polymer of 2,6-anthra-9,10-quinone dicarboxylic acid with 1,6-diaminohexane. Reducible monomers may also be polymerised with diisocyanates or diols to form polyurethanes or may be bonded to polyurethanes. An example of the latter is the reaction product of 2-bromomethyl-9,10-anthraquinone with the polyurethane from toluenediisocyanate and 1,6-hexandiol.
Preferably, the composition according to the invention comprises a reducible organic compound and an activated oxygen species-scavenging form, both of which are present in polymerised form(s).
Where the reducible organic compound is dispersed or dissolved in a polymer which does not readily donate a hydrogen atom or electron to the reducible organic compound in its excited state, an additional source of labile hydrogen or electron is preferred. Such a compound is preferably one containing a hydrogen bonded to nitrogen, sulfur, phosphorus or oxygen especially where a hydrogen is bonded to a carbon atom bonded to the abovementioned heteroatom. Alternative sources of electrons are salts of organic compounds such as the salts of sulfonic acids or carboxylic acids. In one form of the invention the sodium sulfonate salt of a polymerised 9,10-anthraquinone would be used. Thus the reducible organic compund itself can be the source of its own electron for the reduction process.
The reduced form of the organic compound used in the composition, brings about a reduction in the molecular oxygen concentration in the atmosphere or liquid through its oxidation by the molecular oxygen, the reduction and/or oxidation being independent of the presence of a transition metal catalyst and, preferably, also independent of the presence of an alkali or acid catalyst. Nevertheless, transition metal compounds, alkaline and/or acidic agents may also be included in the compositions where they may effect the rate of oxygen scavenging or may enhance the reduction and/or subsequent oxidation of the organic compound. For example, ascorbic acid may be included in the compositions comprising anthraquinones as a photoreduction enhancer.
Reduction of the reducible organic compound may take place only when convenient. This might be, for example, when the composition is being made into or brought into association with packaging material or, alternatively and perhaps more usually, after formation of a package and prior to filling and sealing. Reduction may even be deferred until after sealing of the package.
Thus, in a second aspect, the invention provides a method for reducing the concentration of molecular oxygen present in an atmosphere or liquid, comprising exposing the atmosphere or liquid to a composition according to the first aspect and thereafter, reducing the reducible organic compound.
Alternatively, the invention provides a method for reducing the concentration of molecular oxygen present in an atmosphere or liquid, comprising exposing the atmosphere or liquid to a pre-reduced form of a composition according to the first aspect.
The compositions according to the invention may be used independently or as components of blends. They may take the form of a cross-linked polymeric matrix, as in a can lacquer, or be bonded to or absorbed onto an inorganic polymer, such as silica. They may be effectively applied as, or incorporated in, for example, bottle closure liners, PET bottles, liners for wine casks, inks, coatings, adhesives, films or sheets either alone or as laminations or co-extrusions, or they may take the form of pads, spots, patches, sachets, cards, powders or granules which may be attached to packaging material or located independently within a package.
Films comprising the composition according to the invention may be monolayer or multilayer laminate, and may be used on their own or may be affixed or applied to a solid substrate (eg, a solid packaging material). Where the film is a multilayer film, it is preferable that an outer layer is an oxygen barrier film, so that the film may be used in a manner such that only the layer(s) containing the reducible organic compound is exposed to molecular oxygen from the atmosphere or liquid for which a reduction in molecular oxygen concentration is required.
Films comprising the composition may also be used is as a chemical barrier to oxygen transmission through a packaging material. Thus if a packaging material has a certain oxygen permeability, the oxygen passing through it from the outside environment into a reduced oxygen content atmosphere within the package can be scavenged by the reducible organic compound. The composition can be dissolved or dispersed within the packaging material or can be placed adjacent to it as an additional layer on the inner side of the package.
In multilayer laminate films, an activated oxygen species-scavenging component may be provided in a seperate layer from the layer comprising the activatable component.
Film layers containing a reducible organic compound may be formed either from molten plastic compositions extruded to give a particular shape or dimensions or from a liquid state which gives the final solid layer by reaction, or evaporation of a volatile liquid. Plastic compositions will often be extruded at temperatures between 50° C. and 350° C. depending upon chemical composition and molecular weight distribution. Extrusion may be via a die to give a film layer either alone or as a component layer of a multilayer coextrusion. The layer comprising the reducible organic compound may be extruded onto another substrate as in extrusion coating and lamination. Extrusion may be followed by moulding as in injection or blow moulding. These processes can involve the formation of foams in some instances.
The composition according to the invention may also take the form of a printing ink, coating or lacquer. These may or may not be pigmented. The printing inks, coatings and lacquers will normally be applied in a liquid state and solidified by evaporation of the solvent or dispersion medium or by reaction of some of the constituents.
While the composition and methods according to the invention are likely to be of particular value in food-packaging situations where oxygen removal is desirable, their utility is not limited thereto. Other applications include, for example, the generation of low-oxygen atmospheres in vessels for anaerobic or microaerophilic microbiology, or the generation of low-oxygen gas for blanketing flammable or oxygen-sensitive materials. The technology can also be used in conjunction with technologies based on other means of oxygen scavenging such as photosensitized generation of carbon dioxide.
Compositions according to the invention may be re-reduced, if necessary, by resubjecting to the predetermined condition to recommence oxygen scavenging. This may be particularly useful if the composition has been exposed to air prior to package sealing. Re-reduction may be achieved at a light intensity as low as ambient room illumination for an hour depending upon the amount of re-reduction required.
In addition to the advantages disclosed above, the method can, in some instances, be practised with compositions formulated to be self-indicating in respect to their capacity for oxygen removal. That is, some reducible organic compounds upon reduction will undergo a change in colour or change in UV-visible, infrared or near-infrared absorption spectrum. For example, photoreduction of quinones and some of their derivatives results in a spectral shift from the UV to longer wavelengths, especially to the visible region of the spectrum; by incorporation of such compounds, package material can be formulated which will undergo a colour change as the capacity for reducing the oxygen concentration becomes exhausted.
This colour change also provides a mechanism for checking whether all of the reducible organic compound in the composition has been reduced. Where reduction is found to be incomplete, the composition may be resubjected to the predetermined conditions. Further, such compositions may also be used as an indicator of seal breakage. That is, in the area of film where a heat seal or other seal is made between the film containing the reducible organic compound and a material of sufficiently high oxygen barrier, oxygen cannot reach the reducible organic compound as fast as it can in other areas. The seal area therefore remains coloured due to the presence of reduced organic compound. The fluorescent emission from the reduced organic compound is particularly useful for this purpose. A green fluorescence is seen when 9,10-anthraquinone with substitutents in the 2-position are bonded by a methylene group to the ring. Alternatively, a strip or ring of the composition may be located on the inner side of the sealed package adjacent to the seal. Where the seal is formed by an adhesive, the composition may comprise the adhesive. If the seal should be incomplete or become broken in any way, then this may be detected by a colour change in the composition.
Visible colour changes may be detected by eye, whereas changes in UV-visible, infrared or near infrared absorption spectrum may be measured with an appropriate device such as a photocell used with a light source of appropriate wavelength and intensity.
The invention will now be further described with reference to the following non-limiting examples and figures.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 : Photoreduction of 2-methyl-9,10-anthraquinone (0.075 M in ethyl cellulose, heat sealed between two layers of PVDC-coated polypropylene). Spectra show the photoreduction of the sample under xenon lamp irradiation (0, 30, 90, 180, 300 and 600 seconds) and detail the decline of the peak at 327 nm, with a corresponding increase in the peak at 375 nm, as irradiation time increases.
FIG. 2 : Photoreduction of 2-methyl-9,10-anthraquinone (0.075 M in ethyl cellulose, heat sealed between EVOH barrier laminate and SURLYN1601) under xenon lamp irradiation (0, 30, 90, 180, 300 and 600 seconds). The peak at 327 nm decreased with increasing irradiation time, while the peak at 375 nm increased until approx. 300s irradiation, when it began to decrease.
FIG. 3 : Reoxidation of reduced species in air after storage for 106 days under nitrogen. The reoxidation involves the gradual loss of the peak at 375 nm with a corresponding increase in the peak at 327 nm. The three spectra shown above correspond to the film sample reduced, and then after 1 day and 21 days left to oxidise.
EXAMPLE 1
Photoreduction and Reoxidation of Anthraquinone in Ethyl Cellulose
9,10-Anthraquinone, 0.05 g, and ethyl cellulose (degree of substitution, 2.5), 1.5 g, were dissolved in ethyl acetate, 12 ml. The solution was cast onto plastic coated glass to give a film 10-15μ thick when the solvent had evaporated. A sample of the film was placed in a nitrogen flushed spectrophotometric cuvette and the absorbance at 252. nm and 264. nm was measured.
While still in the cuvette under nitrogen, the sample was irradiated for 20 seconds with light from a xenon lamp using a Suntest CPS instrument, and the ratio of absorbance at 254.8 to that at 264.3 measured. The sample was exposed to air for a total of 10 days to allow reoxidation of the anthrahydroquinone and/or the semi-quinone, which would result in the absorbance ratio returning towards its initial value. The results in Table 1 show that photoreduction occurs on irradiation, followed by reoxidation upon exposure to air. Slight shifts in A max occurred with reduction and oxidation.
TABLE 1
Absorbance Ratio
Treatment
254.3/264.3
252.4/264.3
252.8/264.3
None
2.10
Irradiated (20s)
0.93
3 days in air
1.44
6 days in air
1.49
10 days in air
1.50
EXAMPLE 2
Photoreduction of 2-methylanthraquinone in Ethyl Cellulose Sandwiched between Two Layers of Polyvinylidine Chloride Copolymer-coated Polypropylene
2-methyl-9,10-anthraquinone (hereinafter referred to 2-methylanthraquinone or MeAq), 0.0167 g, was dissolved in ethyl acetate, 9 ml, together with ethyl cellulose, 1.15 g, and a film was cast as in Example 1. The film was 20-30 μm thick. A strip of this film was placed between two layers of the PVDC-coated polypropylene, and the two outer layers were heat sealed together to form a flat package containing the ethyl cellulose layer with essentially no headspace.
The 3-layer sample was held in a steel clamp and exposed for seven time intervals to the light from the xenon lamp as in Example 1. The maximum exposure was 10 minutes and the absorption spectrum was measured with a spectrophotometer after each exposure. The results in FIG. 1 show the decrease in absorbance due to 2-methylanthraquinone at 327 nm with increase in absorbance at 375 nm (and at longer wavelengths) due to progressive formation of the corresponding anthrahydroquinone and/or semiquinone.
These results indicate that a barrier plastic film permits the photoreduction of the 2-methylanthraquinone without the interference by atmospheric oxygen.
EXAMPLE 3
Photoreduction of 2-methylanthraquinone in Ethyl Cellulose Sandwiched between a Layer of Surlyn 1601 (Du Pont, Wilmington, USA) and a Co-extruded Film of Surlyn, Ethylene Vinyl Alcohol Copolymer and Nylon 6
A sample of the ethyl cellulose film described above in Example 2 was placed between one high-permeability layer (Surlyn 1601) and one low-permeability layer (the co-extrusion) containing ethylene vinyl alcohol as barrier. This would allow testing whether the low barrier is sufficient to stop oxygen interference with the photoreduction.
The film sandwich was illuminated and the spectra were measured as in Example 2. The spectra in FIG. 2 show that the quinone is photoreduced but with some decrease in efficiency compared with the previous Example and with some evidence of side reaction. This result indicates that the oxygen permeability of either the layer provided by the Surlyn or the layer containing the quinone should preferably be reduced.
EXAMPLE 4
Scavenging Oxygen from Air in Pouches Made from a High-oxygen-barrier Plastic
2-Methylanthraquinone, 0.05 g, was dissolved in ethyl acetate, 9 ml, together with ethyl cellulose, 1.25 g and a film cast 19 cm×18 cm on the Surlyn side of the co-extruded film described in Example 3. This sample was termed the “control” and was folded to form a pouch of dimensions 23 cm×20 cm. The pouch was flushed with nitrogen and exposed to xenon lamp irradiation as per Example 3 for 3 minutes. Some nitrogen was then removed by syringe via a septum and air, 20 ml, was added and the oxygen content measured by gas chromatography. (The quantity of 2-methylanthraquinone is approximately equimolar with 4 ml of oxygen.) The pouch was then stored in darkness.
Three additional pouches were prepared in a similar fashion but with the addition of triphenylphosphine to scavenge the hydrogen peroxide or formed derivative. The quantities of triphenylphosphine were 0.059 g, 0.118 g and 0.295 g. These pouches were treated in the same manner as the pouch from the “control”.
The oxygen content of the hour pouches was determined again after storage for 25.3 hours and the initial and final results are shown in Table 2.
The film has an oxygen transmission rate of 6 cc/m 2 /day/atmosphere at 20° C. 75% RH.
TABLE 2
Oxygen scavenging in the presence of triphenylphosphine
Initial
Oxygen
Final
Triphenylphosphine
oxygen
After
oxygen
(g)
(%)
25.3 hrs (%)
(%)
0
20.3
16.1
14.05
0.059
10.45
3.9
2.8
0.118
15
1.17
0.35
0.295
14.6
0.07
0.16
Preparation of the films was repeated with an additional one containing triphenylphosphine at a level of 0.59 g, as well as the 2-methylanthraquinone, but this time the pouches were opened after irradiation and the ethyl cellulose layers removed, placed in Quickfit test tubes and stoppered. The test tubes were stored in darkness for 24 hours.
Potassium iodide, 1% w/w in water was prepared and 4 ml of this solution was added to each of the test tubes. Freshly prepared starch mucilage, 2 ml, was also added and the test tubes were shaken vigorously for 30 seconds. The test tubes were allowed to stand in darkness. After 5 minutes the test tube containing the “control” film contained black stained film due to the release of iodine formed through action of the hydrogen peroxide or its derivative. The film containing triphenylphosphine, 0.059 g, showed a slight blue stain only after 3 days. The remaining films showed no evidence of iodine formation indicating no release of hydrogen peroxide from the films.
EXAMPLE 5
Oxygen Scavenging Using a Polymerised Reducible Organic Compound
2-Vinylanthraquinone, 0.25 g, was dissolved in benzene, 30 ml, and benzoyl peroxide, 0.1 g, was added. The solution was degassed by free-thaw evacuation and polymerisation was carried out at reflux temperature for three hours during which time a precipitate was formed. The solvent was removed and the polyvinylanthraquinone was mixed with triphenylphosphine, 0.059 g, and octanol-1-ol, 5 drops, in chloroform. The resulting solution was cast on the Surlyn side of the co-extrusion described in Example 3, with an area of approximately 25 cm×20 cm. A pouch was formed by heat-sealing this film to another piece of co-extrusion and the air was removed by evacuation. Nitrogen was injected into the pouch and this was irradiated as in Example 4. Most of the nitrogen was removed and replaced with air, 20 ml, as in Example 4.
The oxygen content of the pouch was found to be 17.4%. The pouch was held in darkness and the oxygen content was found to be 10.7% after 4 hours and 10.6% after 22.5 hours.
EXAMPLE 6
Oxygen Scavenging by 2-methylanthraquinone in a UV-cured Varnish
A mixture of a commercial UV-curable varnish, 50 parts, and ethanol, 50 parts, was used to dissolve 2-methylanthraquinone as a 5% solution. This mixture was applied to a polypropylene film as a 2 to 3 μm thick layer using a pilot scale coating machine. Strips of the coated polypropylene approximately 20 cm×20 cm, were cut and placed in pouches made from the film described in Example 4. After nitrogen flushing the pouches were exposed to xenon lamp irradiation for periods of time shown in Table 3. The nitrogen was removed and 200-250 ml of nitrogen containing 0.5% oxygen was injected into each pouch. The scavenging of oxygen was determined by gas chromatography and the volume of oxygen consumed after 1 hour is shown in Table 3.
TABLE 3
Oxygen scavenging by a UV-cured
varnish containing 2-methylanthraquinone
% of total oxygen scavenged
Irradiation Time (sec)
after 1 hour
1
50
2
28
3
3
4
31
5
27
6
19
Similar results were obtained when ethyl cellulose was used instead of the UV-curable varnish.
EXAMPLE 7
Oxygen Scavenging in the Presence of Carbon Dioxide
Two pouches were prepared as described in Example 4 with triphenylphosphine and 2-methylanthraquinone contents of 0.118 g and 0.055 g respectively in the ethyl cellulose layer, 1.25 g. After nitrogen flushing and irradiation as per Example 4 the pouches were evacuated and filled with 20 ml each of air and carbon dioxide. The pouches were stored in darkness and the oxygen concentration was monitored by gas chromatography.
The results are shown in Table 4 and comparison with the result for the corresponding pouch without carbon dioxide after 25.3 hours storage (Table 2) shows very little difference in scavenging rate. Current scavengers based on iron powder are often inactivated or have their scavenging rate severely retarded by the presence of carton dioxide.
TABLE 4
Oxygen Concentration (%)
Time (h)
Pouch 1
Pouch 2
0
8.3
7.8
5.5
6.2
6.3
22.0
3.3
3.4
46.0
1.9
1.4
EXAMPLE 8
Stability of Scavenging Capability
The reactivity towards oxygen of the photoreduced 2-methylanthraquinone in ethyl cellulose after 106 days storage in the absence of oxygen was demonstrated as follows. Ethyl cellulose, 1 g and 2-methylanthraquinone, 0.018 g, were dissolved in ethyl acetate, 9 ml, and cast as five films measuring approximately 10 cm×10 cm×2 q0 μm on the surface of the co-extruded barrier film based on ethylene vinyl alcohol described in Example 3.
One of these coated films was made into a pouch and the air was removed and replaced by nitrogen. The film was irradiated as in Example 4 and the pouch was stored in an atmosphere of nitrogen for 106 days. The UV-visible spectrum was measured after which the pouch was opened to allow air to replace the nitrogen in the pouch. The spectrum was measured after one day and 3 weeks.
The spectra are shown in FIG. 3 which shows that the reduced species reoxidises with a decrease in absorbance at wavelengths above 350 nm and and increase around 330 nm characteristic of the reoxidation of the anthrahydroquinone or semiquinone species to the quinone form.
EXAMPLE 9
Photoreduction and Reoxidation of 2-methylanthraquinone in the Presence of Poly(4-vinylpyridine)
A solution of 2-methylanthraquinone and ethyl cellulose in ethyl acetate was prepared and cast into 2 separate films as in Example 4. One of the films was coated over part of its area with a film of poly(4-vinylpyridine), PVP, made by casting a solution of 0.7 g of polymer from methanol solution followed by solvent evaporation.
The film samples were formed into pouches and irradiated using the techniques described in Example 4. After irradiation the pouches were opened and the excess co-extruded barrier packaging material was cut off. The samples were placed with the ethyl cellulose-coated side uppermost in plastic dishes where they were left in air for 4 days.
The samples were then covered with the starch/potassium iodide solution described in Example 4. The solution covering the sample not coated with PVP turned dark blue/black within a few minutes. The solution covering the PVP-coated area of the second sample did not become coloured even after several hours whereas the solution covering the uncoated areas coloured the same as was found with the uncoated sample.
The results indicate that the PVP scavenged the oxidizing species such as hydrogen peroxide formed in reoxidation of the photoreduced 2-methylanthraquinone.
EXAMPLE 10
Oxygen Scavenging in the Cold
A pouch was made from film comprising 2-methylanthraquinone, 0.055 g, with ethyl cellulose, 1.25 g and triphenylphosphine 0.118 g as described in Example 4. 20 ml of air was added and the pouch stored at −1.0 to 1.0° C.
Results:
Time (days)
% oxygen
0.0
19.6
1.
8.04
2.
6.22
3.
4.49
6.
3.03
13.
1.64
17.
1.21
41.
1.13
EXAMPLE 11
Dependence of Scavenging upon Irradiation Time and Delay between Irradiation and Exposure to Air
Ethyl cellulose, 1.2 g, and 2-methylanthraquinone, 0.118 g, were dissolved in ethyl acetate, 9 ml, and cast as four films onto the Surlyn side of CSDE film and made into pouches with the test film folded over onto itself and a half slice of tissue inserted between. All were vacuum packed in the Turbovac, then two were given a total of five minutes irradiation (half each side) and the other two ten minutes. One each of the pouches immediately had 20 ml of air injected, the other two being left overnight before they too had 20 ml of air introduced. This tested for whether leaving the films after reduction has any effect on their oxygen scavenging.
Results:
Filled immediately
Left overnight
Time (h)
5 M
10 M
5 M
10 M
0.0
21.
21.
21.
21.
2.
6.49
5.91
4.5
6.35
6.32
19.5
0.57
0.3
21.8
0.75
0.29
24.
0.23
0.28
28.8
0.27
50.
0.2
The results show that irradiation time may have some effect on rate of scavenging, but it is small between 5 and 10 minutes. Also, leaving the pouches prior to filling seems to have no effect.
EXAMPLE 12
Peroxide Scavenging from a Separate Film
Films Cast:
MeAq (g)
NQ (g)
TPP (g)
EthCell (g)
0.055
—
—
1.2
—
0.039
—
1.2
—
—
0.118
1.2
The 2-methylanthraquinone and 1,4-naphthoquinone (NQ) films were cast directly onto CSDE, with the triphenylphosphine (TPP) films cast onto polethylene cling wrap, then placed on top of the others, flattened out, and the edges taped down. Holes were punched through the TPP film so that it would not blow up when placed in the Turbovac. Bags were vacuum packaged and given 10 minutes irradiation before having 20 ml of air injected.
Results
% oxygen
Time (h)
MeAq
NQ
0.0
21.
21.
2.
14.45
4.8
17.75
18.8
5.03
23.3
12.
25.8
4.47
44.3
1.89
89.
2.86
114.8
0.61
166.3
1.28
187.3
0.81
EXAMPLE 13
Photoreduction on the Coater-laminator
Films cast:
MeAq (g)
TPP (g)
EthCell (g)
0.055
0.118
1.2
—
0.12
1.2 (onto polyethylene
cling film)
0.055
—
1.2
Pouches were set up in a similar way to previous examples, but irradiation was with a coater-laminator at a web speed of 5 m/min. The UV lamps cast a beam of light approximately 10 cm long, and thus the samples were irradiated for an average of 1.2 seconds. As in previous tests, 20 ml of air was injected.
Results:
% oxygen
Time (h)
Type a
Type b
Type c
Type d
0.0
21.
21.
21.
21.
2.
13.47
17.87
4.5
12.91
16.12
5.3
5.95
2.05
7.
2.35
0.36
11.53
15.77
24.
0.17
77.
2.18
10.89
a and b -MeAq and TPP in the one film.
c and d -TPP was in ethyle cellulose cast on polyethylene cling film.
The results appear to show that the scavenging performance is unaffected by the different method of photoreduction, and this was supported by the intense fluorescent colour of the film straight off the coater.
EXAMPLE 14
Stoichiometry of the MeAO Reoxidation
Films cast:
MeAq (g)
TPP (g)
EthCell (g)
0.055
0.118
1.2
Film was set up in a similar manner to previous examples, and irradiated for 10 minutes with the Xenon lamp before injecting 60 ml of air (ie, oxygen:MeAq ratio of 3:1).
Results:
Time (h)
% oxygen
0.0
21.
89.5
9.52
115.
9.36
This result indicates a scavenging ratio of 1.7 moles of oxygen scavenged per mole of MeAq. Extraction and HPLC/V-VIS revealed that no TPP was present (2:1 molar ratio with MeAq) and this may be confirmation that more than a 1:1 molar amount of peroxide was produced by the MeAq reoxidation.
EXAMPLE 15
Ferrous Sulphate as a Peroxide Scavenger
Films cast:
MeAq (g)
F. Sul (g)
EthCell (g)
0.055
0.344
1.2
Pouches were prepared in a similar manner to the previous examples with the ferrous sulphate heptahydrate (F.Sul) (ground into fine powder) dispersed through it. The pouch vacuum packed, and irradiated for 10 minutes in the Xenon lamp, before 20 ml of air was injected.
0.0
21.
2.3
16.27
18.8
7.42
25.5
5.46
114.8
2.53
142.8
2.07
190.8
1.6
260.8
3.17
The results suggest that oxygen scavenging is slower than when TPP is used
EXAMPLE 16
Anthraquinone-2-aldehyde (AO2A): Inbuilt Peroxide Scavenging
Films cast:
AQ2A (g)
TPP (g)
EthCell (g)
0.058
—
1.2
0.058
0.118
1.2
Two films each were cast with the above quantities and vacuum packed before being irradiated for 10 minutes with the Xenon lamp and injected with 20 ml of air.
Results:
Time (h)
AQ2A1
Time (h)
+TPP1
0.0
21.
0.0
21.
2.3
17.02
2.
8.61
19.3
15.
4.
5.33
44.8
14.52
75.5
0.62
121.5
12.44
EXAMPLE 17
PEF as Peroxide Scavenger
Films cast:
MeAq (g)
PEF (g)
EthCell (g)
0.055
0.072
1.2
Two pouches were made, the bis(furfurylidene) penta-erythritol (PEF) being 1:1 w.r.t. MeAq, vacuum packed, irradiated for 10 minutes with the Xenon lamp, and injected with 20 ml of air.
Results:
Time (h)
MP1
MP2
0.0
21.
21.
4.
15.91
15.32
23.3
10.84
12.94
69.
7.38
12.78
148.5
2.29
1.82
EXAMPLE 18
Cellulose Acetate as Scavenging Medium
Films cast:
MeAq (g)
TPP (g)
Cel. Ac. (g)
0.1
0.1
1.4
The pouches were prepared in a similar manner to previous examples and were irradiated with the Xenon lamp.
Results:
Time (h)
CA1
CA2
0.0
21.
21.
5.3
19.2
8.57
23.5
1.3
1.05
30.3
5.14
0.38
EXAMPLE 19
LAMAL Adhesive—TPP Peroxide Scavenging
Films cast:
EtAq
L-HSA
L-C
EtOH
TPP
(g)
(g)
(g)
(g)
(g)
0.1
1.8
0.2
3.
0.24
EtAq = 2-ethyl-9, 10-anthraquinone
L-HSA = polyurethane base polymer
L-C = cross linking agent for the polyurethane
Films were cast onto warm plate (covered with polyester/polyethylene laminate) using the TLC spreader with a gap of 300μ. The adhesive was then laminated with PVC cling-wrap, and injected with 20 ml of air.
Results:
Time (h)
Lamal 1
0.0
21.
1.5
12.01
18.5
0.62
22.3
0.47
The results indicate that the films work well, although perhaps a little slower than TPP in ethyl cellulose.
EXAMPLE 20
LAMAL—Triisopropyl Phosphite (TIP) Peroxide Scavenging
Films cast:
EtAq
L-HSA
L-C
EtOH
TIP
(g)
(g)
(g)
(g)
(g)
0.1
1.8
0.2
3.
0.2
Two samples were prepared as in Example 19.
Results:
Time (h)
Lamal2
Lamal3
0.0
21.
21.
3.
13.86
17.42
21.5
9.63
7.23
45.
4.19
5.36
189.
3.61
4.26
EXAMPLE 21
Triisopropyl Phosphite Peroxide Scavenging from Ethyl Cellulose
Films Cast:
EtAq (g)
TIP (g)
EthCel (g)
0.1
0.1
1.2
Film was cast onto EVOH barrier material using the TLC spreader with a gap of approximately 400μ vacuum packed and irradiated as in previous examples.
Results:
Time (h)
TIP1
TIP2
0.0
21.
21.
2.3
19.46
12.01
22.2
7.14
5.58
96.3
4.03
0.36
452.
0.24
0.18
EXAMPLE 22
Use of Gamma-irradiation for Activation of Ethyl Cellulose Films
A cobalt-60 source was used to provide a dose of 25 kilogray to films containing ethylanthraquinone and triphenylphosphite. The films were made as described below and the results provided in Table 5.
Ethylanthraquinone, 0.13 g, triphenylphosphite, 0.385 g, and ethyl cellulose, 3.3 g, were dissolved in ethyl acetate and the resulting solution was spread on two sheets of poly(ethylene-terephthalate); 12 μm thick with the aid of a doctor blade. The solvent was evaporated by warming to approximately 40° C. for 10 minutes in a fume hood. The resulting plastic films had an area of 18 cm×22 cm and was on average μm thick.
The films prepared as above were placed in pairs in the bags and either smoothed manually before sealing or were sealed under vacuum followed by addition of a known volume of air or nitrogen. The bags were made either from metallised polyester laminated to polyethylene or were bag-in-box liners which contained an inner duplex liner of polyethylene as well as a sealed value socket. The area of each side of all bags was 18 cm×22 cm.
The volume of air initially in each bag was between 200 ml and 300 ml. It can be seen that the film consumed oxygen highly efficiently.
EXAMPLE 23
Use of Gamma-irradiation for Activation of Ethylene Vinyl Acetate (EVA) Films
The irradiation treatments and the bags were the same as in Example 22. The EVA films were cast from toluene solutions containing the compositions shown below. The EVA was obtained as a gel (Morton Chemical Co., USA) under the trade name Adcote 1133.
The Cetyl alcohol was used as the photoreducing agent supplying labile hydrogen or electrons, a function which appears to be served by the polymer itself in the case of the ethyl cellulose, cellulose acetate, and polyurethane adhesive (Lamal).
Cetyl alcohol, 0.32 g, triphenyl phosphite, 0.68 g, and 2-ethylanthraquinone, 0.4 g, were dissolved in the toluene gel of EVA, 12.5 g, to give a mobile solution. This was then cast into a film layer on the heat seal side of a 2 sheets of oxygen barrier plastic of ionomer/EVOH/polyester of oxygen transmission rate/cm 3 /m 2 /24 hr/atmosphere at 25° C., 75% RH. The area of film and thickness were as in Example 22.
The scavenging of oxygen present either prior to irradiation or injected into the bag after irradiation is shown in Table 6.
TABLE 5
Oxygen %
Bag
Initial
Final 1
Activatable Component
PET/Pe
20.6
9.0
2-EtAQ 2
PET/Pe
20.6
8.3
2-EtAQ
Bag-in-Box
20.6
2.8
2-EtAQ
Bag-in-Box
20.6
5.6
2-EtAQ
1 3 days after γ-irradiation
2 2-ethylanthraquinone
TABLE 6
Oxygen %
Bag
Initial
Final 1
Activatable Component
Bag-in-Box
20.6 3
14.1
2-EtAQ 2
Bag-in-Box
20.6 3
10.8
2-EtAQ 2
1,2 as per Table 5
3 air injected 24 hours after irradiation.
EXAMPLE 24
Activation with Electron Beam
Films Cast:
Sample
EtAq (g)
TPP
TIP
EthCell (g)
A
0.06
0.12
1.2
B
0.06
0.14
1.2
Pouches were prepared in a similar manner to previous examples. The total volume of the bags was measured, and this value was used to calculate the volume of oxygen (from air) initially present. Oxygen analysis was carried out 23 hours after the pouches were made, and the volume of oxygen scavenged calculated. This was then converted into the percentage of the stoichiometric amount scavenged (% Stoich.), which compares the actual volume of oxygen scavenged with the theoretical maximum which could be scavenged (assuming a 1:1 interaction of oxygen with anthraquinone).
Results:
Sample
Dose Rate (MRads)
% of Stoich
A
3.0
68
B
1.1
32
C
3.0
80
The results show that the electron beam is an efficient method of inducing photoreduction and bringing about oxygen scavenging, even at lower dose rates.
EXAMPLE 25
Oxygen Scavenging from a Tinplate Can
A crosslinkable polyurethane resin was used to demonstrate the use of an oxygen-scavenging coating on the inside of a tinplate can.
A can of volume 465 ml was coated internally with a solution of Lamal HSA, 3.64 g, and Larmal C, o.54 g, 2-ethylanthraquinone, 0.33 g, and triphenylphosphite, 0.33 g, in ethanol 6 g. The solvents were evaporated at 50-60° C. leaving a coating of polyurethane resin containing 2-ethylanthraquinone and triphenylphosphite on the inside of the can. The can was then exposed to irradiation in the solar simulator for five minutes and then filled loosely with glass beads to reduce the headspace to 170 ml and the can was then sealed by double-seaming.
The headspace gas was anaylsed after 24 hours by which time the oxygen concentration had been reduced from 20.6% to 19.5%. The oxygen consumed was 2.5 ml. This represents the quantity of oxygen which can be found sometimes in commercial cans.
EXAMPLE 26
Oxygen Scavenging with a Copolymerised Reducible Organic Compound
Copolymers of 2-vinylanthraquinone were made with styrene (STY) and with 2-hydroxyethyl methacrylate (HEMA). The copolymers contained approximately 9 moles % of polymerised anthraquinonoid monomer.
Films were cast on the Polyester/EVOH/Surlyn barrier film as described in other examples using the quantities shown below. The HEMA copolymer and its blend from ethyl cellulose were cast from ethanol and the styrene copolymer was cast from a mixture of chloroform (70%) and acetone (30%). The films were made into pouches and the air was removed as in other examples. The pouches were irradiated for 5 minutes on each side in the Suntester solar simulator and 20 ml of air was injected into each pouch, except for that containing the blend which was injected with 50 ml of a mixture of 2.1% oxygen in nitrogen.
Quantities of Ingredients (g)
HEMA
STY
Cetyl
Ethyl
Test
Copolymer
Copolymer
C 6 H 5 O) 3 P
Alcohol
Cellulose
A
0.6
—
0.11
—
—
B
0.25
—
0.10
—
1.0
C
—
0.5
0.11
0.09
—
Results:
% Oxygen
Time (h)
Test A
Test B
Test C
0
21.0
2.1
21.0
17.0
—
1.2
—
64.7
15.4
—
16.0
The results show that the polymers scavenge oxygen, but their permeability to oxygen can result in slower scavenging than with a highly permeable film such as ethyl cellulose.
It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.
|
The claims are drawn to a method of detecting seal breakage or incomplete seal formation in a package, said method comprising the steps of: (i) providing said package, prior to sealing, with a strip or ring of an indicator comprising an oxygen scavenging composition which includes a source of labile hydrogen or electrons and at least one reducible organic compound, wherein said strip or ring is located on an internal surface adjacent to where a seal is to be formed, (ii) treating the strip or ring with electromagnetic energy so as to reduce the reducible organic compound to a reduced form which is oxidizable by ground state molecular oxygen regardless of the presence of a transition metal catalyst and such that, when oxidized, there is a detectable change in a characteristic of said composition selected from the group consisting of: colour, fluorescence emission and UV-visible, infrared or near-infrared absorption, (iii) subjecting said package to a sealing process intended to seal the package, and (iv) detecting, in the sealed package, a change in said characteristic of said composition, wherein any detected change is indicative of seal breakage or incomplete seal formation.
| 8
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to clock systems employed to synchronize or to time the operation of data processors, logic circuits and input-output units associated with electronic data processing systems. More particularly, this invention relates to a switching circuit for selecting one of a plurality of normally operable asynchronous oscillators employed in timing circuits so as to assure synchronization and to avoid metastability.
2. Discussion of the Prior Art
It is well known that two computers or elements of a complex data processing system which attempt to communicate with each other in a random asynchronous manner are susceptible of creating a metastable condition. For purposes of this invention, a metastable condition is defined as an attempt to change the state of a logic element before the element has had time to become stable or enabled sufficiently to accept or sense the change signal. This creates a condition which will not assure that the desired output is correct. The output of a logic element which is in a metastable condition may be correct or incorrect.
In theory, two viable alternatives have been suggested to circumvent the problem of metastability and interface synchronization. First, permit the parts of the system to remain nonsynchronous and employ sampling techniques which identify time regions in which metastable conditions do not exist. This first approach creates a time lag which is unacceptable to high speed computing systems. The sampling circuits for such a complex system may become costly and difficult to implement.
An alternative approach has been to synchronize all of the interfaces of the components in the system and to create clocking schemes which will guarantee that metastable regions cannot occur. This alternative approach has been implemented is Sperry Univac's distributed processing systems and is described in U.S. Pat. No. 4,021,784.
In the above-identified Sperry Univac system, there are a plurality of clocks associated with a plurality of computers. Each computer has associated therewith, input/output equipment and its own clock. Logic circuits are employed to selectively connect only one of the asynchronous clocks to the total system. The logic circuits are provided with individual timed output lines connected to the central processing units and to the individual input/output units. During a switching operation, all timed outputs are temporarily blocked for a predetermined number of computer cycles. The previous clock is blocked and the new clock is subsequently enabled at least one or more cycle times later. When several clocks are present in a distributed processing system, they are located at the individual processing units and thus are a substantial distance from each other, and such precautions are required as well as being justified.
When a central processing system is provided with a similar frequency back-up clock which is asynchronous with the master clock, or when the central processing system is provided with a substantially slower or faster asynchronous clock, they can be located at or near the master clock. In a typical system having a plurality of asynchronous clocks of different frequencies, the slower clocks are employed for maintenance purposes and may be on the same circuit board.
When a plurality of asynchronous clocks are located close enough to each other to be synchronized or substantially synchronized, the compensation for cable delays can be ignored or easily overcome.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provide an automatic synchronous switching circuit for a plurality of asynchronous oscillators or clocks in a computing system.
It is another primary object of the present invention to provide an automatic synchronous switching circuit for a plurality of asynchronous oscillators of substantially different frequencies.
It is another primary object of the present invention to provide an automatic synchronous switching circuit which employs the new clock pulses to select itself without overlapping the old clock pulses.
It is yet another object of the present invention to provide an automatic synchronous switching circuit which is simple and faster than circuits employed heretofore.
These and other objects of the present invention are provided in a switching circuit having a plurality of asynchronous oscillators normally operable and available at the input of the switching circuit and having only one previously selected oscillator available at the output. A synchronized change from the previously selected oscillator to a newly selected oscillator is implemented by selecting the new oscillator and coupling its output to a first control selection means which provides a delayed synchronized switch signal. The delayed synchronized switch signal is then employed to select itself by coupling it to a second control selection means which provides the newly selected oscillator at the output of the switching circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a general schematic block diagram of a preferred embodiment of the present invention;
FIG. 2 is a detailed schematic block diagram of the preferred embodiment of FIG. 1 showing an implementation using simple gates and flip-flop elements;
FIGS. 3 and 4 are timing charts showing the pulses associated with the schematic block diagram of FIG. 2; and
FIG. 5 is a truth table for the comparator of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Refer now to FIG. 1 showing a general schematic block diagram of a synchronous switching circuit 10. The inputs to the circuit 10 comprise a plurality of oscillators 11, 12 etc. (not shown) designated 1 to N. The oscillators 11, 12 may be of the same frequency or different frequencies. Since the oscillators are not phase locked together, the frequencies are not interdependent and are not synchronized.
Assume for the purposes of discussion that oscillator 11 is operable at input line 13 and its output is being presented at output line 14 as will be explained hereinafter. When it is desirable to switch oscillator 11 off and oscillator 12 on, the change cannot be made simultaneously because it may create a metastable condition in the switching circuit 10 or in the system (not shown) connected to the output line 14.
Assume that the oscillator 11 was previously selected by presenting a select signal on line 15, and now a new oscillator will be selected. If a select signal is still present on line 15 and oscillator N is to be selected, the select signals may be changed simultaneously. In the system shown after the select signal 1 has been employed on line 15 to select oscillator 11, it is not necessary to maintain this select signal and it may be dropped. Raising a select signal on any of the lines 16 through 19 will cause the associated oscillator to be selected. For example, if a signal is raised on select line 19, oscillator N will be selected as follows. Switch selection means (not shown) presents a select signal on line 19 to set the new select storage element 20 which generates a new oscillator selection output signal on line 21, representative of the oscillator "N". The old oscillator select element 22 still retains the previous selected oscillator 11 and is presenting a high output on line 23. When line 21 goes high, the high output of line 21 is presented to AND gate 24 along with the output of oscillator 12 causing a high output at AND gate 24 to be presented to one of the inputs to AND gate 25. The other input of AND gate 25 is a normally low output from comparator 26 on line 27. The output of comparator 26 is normally low when the output of logic element 20 is equal to the output of logic element 22. However, when line 21 goes high and line 23 has been high and is still high, the comparator 26 senses that a change has taken place and the normally low output on line 27 is switched to a high condition. The high condition on line 27 and the high condition on line 28 from AND gate 24 causes AND gate 25 to go high and generate a sync signal on line 29 in synchronism with oscillator 12. It will be understood that the term in synchronism means that the signal being presented on line 29 is delayed by AND gates 24 and 25 as well as the interconnecting lines. When comparator 26 senses the change on the lines from logic elements 20 and 22, the signal on normally low line 27 was changed from low to high. Similarly the output on normally high line 31 is switched from high to low generating an inhibit signal at AND gate 32, thus, blocking the output of formally selected oscillator 11 on output line 14. The sync signal on line 29 is employed as an input to logic element 22 and sets the old select storage element 22 from oscillator 11 to the newly selected oscillator 12 causing the line 33 to go high. Now line 21 and line 33 are high and comparator 26 senses equality output between logic elements 20 and 22 causing normally low line 27 to go low and normally high line 31 to go high again. While this change is taking place at the output of comparator 26, the high signal on line 34 is presented as an enabling input to AND gate 35. The newly selected oscillator 12 is also connected via line 36 as an input to AND gate 35 causing an output on line 37 in synchronism with oscillator 12. Line 37 is connected to AND gate 32 which is now enabled by the high output on line 31 causing the output of AND gate 32 to present the output of oscillator 12 on oscillator output line 14.
A select signal may be generated by a computer or an input device which will present a select signal on lines 15 to 19. It is not necessary that the selection be made manually as may be suggested by the schematic block diagram. Once the selection is made at logic element 20, a sequence of events is generated which causes the selective oscillator signal to be presented at AND gate 25 and the output of AND gate 25 is then employed as its own sync signal to select itself at logic element 22. Thus, it will be understood that it is impossible for an oscillator which selects itself to interfere with itself.
When oscillator 11 is again selected by selection means 15, an output signal on line 30 to AND gate 38 will generate a new sync signal. After AND gate 32 is blocked, the sync signal on line 29 will raise a select signal on line 23 to AND gate 39 effecting the selection of oscillator 11.
Refer now to FIG. 2 showing more specifically a schematic block diagram having only two oscillators designated 11' and 12'. Switch selection means 40 generates a select signal on line 41 and need not designate the particular oscillator. The frequency select signal may instead signal the switching circuit 10' to change from one oscillator to the other oscillator. It will be understood that one of the two oscillators is effective to present an output signal on output line 43. Accordingly, a select-a-new-oscillator signal on line 41 enables the data input D to the D-type flip-flop 42. The oscillator output signal on line 44 is fed back to flip-flop 42 and connected to the clock input. When the clock input goes high, and the D input is high, the Q output of flip-flop 42 goes high at line 45. The high signal on line 45 is applied to the D-type flip-flops 46 and 47 as an enabling signal. Flip-flop 46 is a logic element for retaining the new select signal. The new select signal indicated at data input D of flip-flop 46 is clocked by an oscillator pulse from line 44 which is applied via line 48 to the clock input of flip-flop 46. It will be understood that a predetermined delay 49 may be employed between lines 44 and 48 or the next sequential clock pulse occurring after the clock pulse which triggered flip-flop 42 will clock the enabled data pulse at the D input of flip-flop 46. Since the D input was high when the clock arrived on line 48, it causes the Q output of flip-flop 46 to go high at line 51 and the Q output at line 52 to go low. There is a high input signal on line 51 to OR gate 53 and a low input signal on line 52 to OR gate 54. OR gate 53 enables its side of AND gate 55 and the oscillator signal from oscillator 12' on line 56 passes through OR gate 54 and subsequently through the other side of AND gate 55. The output of oscillator 12' appears at the output of AND gate 55 and appears at the clock input of D-type flip-flop 58. The Q output of flip-flop 58 on line 59 is recirculated back to the data input of the flip-flop 58 producing a divide by two output signal on line 59. To prevent the D-type flip-flop 58 from operating in random fashion, it is always cleared when the clock arrives on line 57 as follows. When D-type flip-flop 46 produced a high output on line 51, it also produced a low input on line 52 which is connected to the A input of comparator 61. The high output signal on line 41, which was applied to the data input of D-type flip-flop 47, has not yet been clocked through flip-flop 47 and the Q output is still low on line 62, presenting a low input to the B input of comparator 61. When the A input is high and the B input is low in comparator 61, the comparator senses that A is greater than B thus generating a high output signal on line 63, which is applied to OR gate 64 and appears at output line 65 as a low unblocking signal applied to the clear side of D-type flip-flop 58. This low signal permits the clock and data signals to produce an output on line 59 of flip-flop 58. The output appearing on line 59 of flip-flop 58 is applied at the clock input of D-type flip-flop 66. The Q output of flip-flop 66 is connected back to the data input of the flip-flop, thus producing a second divide by two element. When the enable signal on line 65 is also applied to flip-flop 66, the inputs on line 67 and 59 are clocked through to the output line 68 thus producing a sync signal. The signal on line 68 is in synchronism with oscillator 12' because it is produced by oscillator 12' but is delayed by the two flip-flops 58 and 66 for a short period of time. The sync signal on line 68 is recirculated back to D-type flip-flop 47 and is presented at the clock input causing the high data signal on line 45 to be produced at the Q output of flip-flop 47 on line 69.
When OR gate 64 produced the enable signal on line 65, it also produced on line 71 a disable signal which was applied to OR gate 72, thus disabling oscillator 11' output on line 43. The high signal on line 69 is applied to OR gate 73 and enables one side of AND gate 74. At this point in time, there is a low signal on line 62 from the Q output of flip-flop 47. Oscillator 12' is presenting high and low signals on line 75 at the input to OR gate 76 and passes through AND gate 74 which has been enabled by line 69 and OR gate 73. The output from AND gate 74 on line 77 was masked initially by the high output on line 71. However, when the data signal on line 45 drove the Q output of flip-flop 47 high, it also drove the Q output of flip-flop 47 low on line 62. When the outputs on line 52 and 62 are both low and A is equal to B, both the 63 and 78 outputs of comparator 61 go low. When the two inputs to OR gate 64 are low, the output on line 65 is high and disabling and the output on line 71 is low and enabling. OR gate 72 has a low input on line 71 when the signal from oscillator 12' on line 77 is applied, thus causing the output on line 43 to be the same as the output of oscillator 12'.
It will be understood that flip-flop 42 always presents one of two states. Thus, either a high or a low signal should be presented on line 41 to hold the flip-flop 42 in one of two states. After one of two signals is presented at flip-flop 42, the flip-flop 42 operates as a switch selection means for generating a select signal indicative of one of the oscillators and the flip-flops 46 and 47 operate as means responsive to this select signal for generating a new oscillator selection output signal in flip-flop 46 and an old oscillator selected output signal in flip-flop 47. The comparator means 61 and OR gate 64 determine whether the flip-flops 46 or 47 are the same, or different which indicates a change has occurred. When a change occurs, the output line 65 is enabled permitting the output from the newly selected oscillator to pass through AND gate 55 to the divide by two flip-flops 58 and 66 to generate the sync signal on line 68 which permits the newly selected oscillator to select itself at flip-flop 47.
After oscillator 12' is selected and it is desired that oscillator 11' be selected, the high signal on line 41 is changed to a low signal. The low signal on line 41 produces a low output on line 45 when the clock signal on line 44 clocks the data input through. A low signal on the data input of flip-flop 46 will produce a high output on line 52 which will enable OR gate 54 and the left side of AND gate 55, thus the oscillator signal from oscillator 11' being presented at OR gate 53 is passed through AND gate 55 and appears on line 57 to subsequently produce a sync signal on line 68 as explained hereinbefore. The sync signal on line 68 causes flip-flop 47 to assume the same state as that of flip-flop 46. Before the sync pulse arrived on line 68 at flip-flop 47, the flip-flops 46 and 47 were in a different state, thus causing comparator 61 and OR gate 64 to enable line 65 and disable line 71. After the sync pulse arrives at flip-flop 47, the flip-flops 46 and 47 are again made to appear the same and line 65 is disabled and line 71 is enabled, thus, permitting the newly selected oscillator 11' to pass its signal through OR gate 72. Line 62 is high enabling one side of AND gate 74. The output of oscillator 11' is applied to the other side of AND gate 74 and line 77 as well as the oscillator output 43.
Refer now to FIGS. 3 and 4 showing the timing waveforms for the elements of FIG. 2. Waveform 81 is the same as the output of oscillator 11' which is appearing on line 79. Waveform 82 is the same as the output of oscillator 12' which is appearing on line 75 and 56. The frequency select signal 83 is shown as a high or low signal which is appearing at line 41 as the input to flip-flop 42. As explained hereinbefore, when the frequency select signal on line 41 was high the oscillator 12' was selected. When the frequency select signal on line 41 was changed from a high to a low signal, as occurs at point 85 of waveform 83, oscillator 11' was selected. There is no overlap of the selection signals. Exaggerated waveform 84 is representative of the output of flip-flop 42 on line 45. Point 86 represents a worse case occurrence of the switching on line 45 and may even represent a metastable condition. Waveform 87, which is the waveform on line 44, is the clock input to flip-flop 42 and edge triggers the data input at a transition point represented by point 85 on waveform 83. Thus, it will be understood that flip-flop 42 is switched into a high or a low state after the frequency select signal waveform 83 changes from high to low or low to high. The low region 88 of waveform 84 is representative of a stable state condition when the clock input of waveform 89 on line 48 appears to switch flip-flop 46. The outputs of flip-flop 46 on lines 51 and 52 are shown as waveforms 90 and 91 occurring after the metastable region 86 of waveform 84. Waveform 92 is representative of the output of one of the two oscillators occurring on line 57, in this case the newly selected oscillator is oscillator 11'. The first positive going pulse, which is permitted on line 57, is shown at point 93 at waveform 92. When waveform 92 goes high and flip-flop 58 is enabled, the output on line 59, which is shown as waveform 94, switches from high to low at point 95 as a result of the transition 93. The next following low to high pulse on waveform 92 is shown at point 96 which causes waveform 94 to go from low to high as shown at point 97. Transition 97 of waveform 94 causes waveform 98 on line 68 to go from low to high as shown as transition 99. Flip-flop 66 is enabled when transition 99 occurs. The leading edge of the sync pulse on line 68 recirculates back to flip-flop 47 which changes the state of the outputs of comparator 61 and OR gate 64, thus, creating the disabled pulse on line 65 which shuts off or changes the output of flip-flop 66 on line 68 (see waveform 98 at point 101). It will be understood that the time delay between transition 99 and transition 101 is approximately the time required for switching four logic elements. In this case the four logic elements which switched are flip-flop 47, comparator 61, OR gate 64 and flip-flop 66. The output of comparator 61 on line 63 and 78 are shown as waveforms 102 and 103. When the input signal on line 52 is greater than the signal on line 62, A is greater than B and a change is in progress as is shown at point 104. As explained hereinbefore, the sync pulse on line 68, shown on waveform 98, terminates the change in progress at comparator 61. The output of OR gate 64 on line 65 is shown as waveform 105 and is an inversion of waveform 102 at point 106. Similarly, waveform 107 which is the output of OR gate 64 on line 71 is the inversion of waveform 105.
Referring now to OR gate 105 of FIG. 2 and waveform 107 of FIGS. 3 and 4, it will be understood that OR gate 72 is enabled and low by waveform 107 until a change in progress takes place at point 108 causing OR gate 72 to be disabled. After the sync pulse 99, 101 occurs on line 68, waveform 107 on line 71 goes from high to low again enabling OR gate 72. During this change in progress that occurs at point 108, oscillator 11' has been substituted for oscillator 12' causing the output on line 43 to appear as shown on waveform 109.
Having explained how oscillator 11' is substituted for oscillator 12', it will be understood that the substitution of oscillator 12' for 11' is initiated by changing the frequency select signal on line 41, shown as waveform 83, from a low to a high condition. This change, shown at point 111 of waveform 83, initiates the change in progress output of comparator 61 shown as point 112 of waveform 103. This change in progress, point 112, also occurs on waveform 105 at point 113. It will be understood that point 113 is an enabling pulse on line 65 and occurs as an inverted pulse on waveform 107 at point 114 and is a disabling pulse at OR gate 72. The enabling pulse 113 results as the generation of a new sync pulse 115 on line 68 of waveform 98. The recirculation of the sync pulse 115 on line 68 back to flip-flop 47 changes the disable pulse 114 from a high level to a low level which again enables OR gate 72. The sync pulse on line 68, which generates the enable condition at OR gate 72, also switches oscillator 11' off and oscillator 12' on at AND gate 74 permitting the signal from oscillator 12' to appear at the output line 43 as shown on waveform 109.
FIG. 5 is a truth table for a preferred embodiment of a comparator such as that shown at block 61 of FIG. 2. In the stable condition the A and B inputs can either be high at both inputs and stable or low at both inputs and stable. During a change in progress, either the A input is high and the B input is low or the converse is true wherein the A input is low and the B input is high. As explained hereinbefore, the unstable condition where the inputs on lines 52 and 62 to comparator 61 are unequal is a condition which lasts for a short period of time until the sync pulse generated on line 68 is recirculated back to flip-flop 47 causing the newly selected oscillator to select itself at the output of AND gate 74 on line 77 which, in turn, generates the selected oscillator output on line 43.
Having explained a preferred embodiment and a detailed embodiment of the invention, it will be understood that various modifications and substitutions may be made in the logic circuitry without departing from the mode of operation and the scope of the invention as defined by the appended claims.
|
A switching circuit for automatically selecting one of a plurality of normally operable asynchronous oscillators is provided with a selection switch for selecting a new oscillator while the formerly selected oscillator is still producing an output. The switching circuit employs the output of the newly selected oscillator to disable the formerly selected oscillator and to subsequently enable the output of the newly selected oscillator to be coupled to the oscillator output of the switching circuit, thus, preventing switch-over from one oscillator to the other during a metastable period.
| 7
|
FIELD OF THE INVENTION
The invention relates generally to a client satisfaction survey method and more particularly to a computer implemented method for surveying a client regarding the level of satisfaction with the value and services received from a service provider.
BACKGROUND
Service providers in many industries rely upon client satisfaction surveys in one form or another to obtain feedback regarding how their clients perceive their performance in providing such services and corresponding support. For example, information technology service providers have employed client satisfaction surveys to gain an understanding of level of satisfaction that clients have with their provided service and support. In this manner, such information technology service providers can determine whether areas or facets of their provided service and support need improvement.
Typically, existing client satisfaction surveys are comprised of questions related to the provided service with the survey taker responding by selecting one of multiple choices directed to respective levels of satisfaction. Such surveys are often distributed in paper form to employees of a client, or electronically through an electronic mail system implemented on internal computer network. Additionally, client employees have been invited to take multiple choice electronic surveys at websites over the Internet.
The results of such surveys are then evaluated and the resulting information is often graphically depicted to facilitate understanding as to those service and support areas with high satisfaction and those service or support areas where improvement may be needed. client satisfaction surveys are often given periodically to ascertain whether such changes have improved client satisfaction those service or support areas needing attention, as well as to identify other service areas needing improvement. Commercially available conventional on-line computer-based software tools for creating the questions of client satisfaction surveys and evaluating survey results include, for example, Zoomerang from MartketTools, Inc. and SelectSurveyASP from ClassApps.com.
However, existing client satisfaction survey tools disadvantageously provide limited options to service providers. For example, a service provider that implemented a remedial change in the service or support it provides must await the results of a subsequent client satisfaction survey to identify if such changes had improved client satisfaction. Moreover, it is often difficult to respond with effective remedial changes as quickly as service providers would like because it would likely require a burdensome number of surveys taken by the client over a period of time. Accordingly, an improved survey method is desired by industries to allow service providers to adapt their services and support for improving client satisfaction without imposing a burdensome number of surveys on the client.
SUMMARY OF THE INVENTION
An improved computer-based survey method of the invention overcomes the previously described disadvantages of existing client satisfaction survey methods. The improved survey method according to the invention includes surveying at least one representative of a service provider providing a service to a client. A plan is then developed for the client based on survey data from the service provider representative survey to address at least one aspect of the provided service that requires changing, if any. The developed plan is then presented to the client. A survey is then taken of at least one representative of the client based on performance of the service provider and the developed plan.
The invention advantageously develops a plan, such as a remedial plan, based on a first survey of the service provider representatives that provide a service to the client and the client is then provided a survey that inquires about the service provider's performance as well as the proposed plan. Accordingly, the invention advantageously exploits the knowledge of those service provider representatives that provide a service to the client for identifying advantageous modifications of the service or support areas before presenting the client with a survey. In such manner, such survey results would enable a service provider to more quickly implement a plan for service changes that would likely increase client satisfaction with a single or reduced number of client satisfaction surveys.
In accordance with another aspect of the invention, the client survey is designed and the responses are analyzed in manner to distinguish between response scores from value-based survey questions and service-based questions. In particular, a services-based weighted average score based on client responses to service-related survey questions is determined and correspondingly, a value-based weighted average score based on client responses to value-related survey questions is determined. In this manner, it would be possible to determine more accurately how the client values its service provider relationship.
Exemplary service providers that may take advantage of the business-to-business invention include information technology services, internal and customer call center services, such as for providing helpdesk services, employee and/or retirement benefit services, marketing, and human resources.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects of exemplary systems and methods according to the principles of the invention are disclosed with reference to the drawings, in which:
FIG. 1 is a block diagram of an exemplary system for implementing the principles of the invention;
FIG. 2 illustrates an exemplary survey flow diagram in accordance with the principles of the invention;
FIG. 3 illustrates an exemplary flow diagram of an improved survey process of a survey computer in accordance with the invention.
FIG. 4 illustrates an exemplary diagram presenting the service-value index of survey results in accordance with another aspect of the invention; and
DETAILED DESCRIPTION
FIG. 1 illustrates a schematic block diagram of an exemplary configuration 100 for implementing the improved survey method according to the invention. The configuration 100 includes a service provider data network system 110 and a client data network system 160 connected to the publicly-accessible Internet and/or electronic mail network 150 . The client that uses the network system 160 receives services or support from the service provider operating the network system 110 .
The service provider network 110 includes service provider computers 120 and 125 coupled to a computer 135 via network 130 . The computers 120 and 125 are used by service provider representatives that, for example, directly or indirectly manage and/or provide a service or services to the client using the network system 130 , or that communicate with or receive information form others that directly or indirectly provide the services or support to such client. The computer 135 selects, organizes, and/or administers satisfaction survey questions to be provided to the clients and will alternatively be referred to as survey computer 135 . The computer 135 is also useable for receiving responses to the survey questions. A database 140 for storing and maintaining survey questions and responses is connected to the survey computer 135 . Accordingly, the survey computer 135 is able to retrieve survey questions from the database 140 as well as communicate survey response data to and from the database 140 .
A network server 115 is coupled between the survey computer 135 and the Internet and/or electronic mail network 150 . A network server 165 of the client system 160 is also connected to the Internet and/or electronic mail network 150 . The client network server 165 is further connected to client computers 170 , 175 and 180 by data network 168 . In accordance with the invention, the client representatives using the computers 170 , 175 and 180 should be directly or indirectly receiving the services or support provided by the service provider, or communicate with or receive information from others that directly or indirectly receive the services or support provided by the service provider. It is also advantageously possible for either or both network servers 115 and 165 to provide an Internet firewall security capability.
It should be readily understood that the respective service provider and client network systems 110 and 160 are depicted as two and three computers, respectively, for illustration and ease of discussion purposes only. The invention is equally applicable to those client and service provider network systems having a significantly larger number of computers coupled thereto.
In operation, the survey computer 135 can provide a first set of survey questions obtained from the database 140 to respective service provider representatives using the computers 120 and 125 . Correspondingly, the service provider network system 110 enables service provider representatives using the computers 120 and 125 to provide their responses to such survey questions to the survey computer 135 for recording in the database 140 . Likewise, the survey computer 135 can provide a second set of survey questions obtained from the database 140 to respective client representatives using the computers 170 , 175 and 180 via the network server 115 , Internet and/or electronic mail network 150 , and network server 165 .
The particular configuration employed for the network systems 110 and 160 depicted in FIG. 1 is for illustration purposes only. The particular method or methods employed by the service provider network system 110 to communicate the survey questions to the respective service provider and client representatives using the computers 120 and 125 and computers 170 , 175 and 180 , as well as for receiving such representatives corresponding responses back to the survey computer 135 is not critical for practicing the present invention. It is only necessary according to the survey method of the invention that the survey computer 135 communicate respective survey questions to and receive responses from respective service provider and client representatives using the computers 120 and 125 and computers 170 , 175 and 180 . It is possible to provide access to the representatives using the computers 120 and 125 to a website established for providing such survey questions form the survey computer 135 and gathering the representatives' responses for communication back to the survey computer 135 .
Moreover, it is also possible to employ different network configurations for communicating the survey questions between a survey computer and service provider and client representatives than that shown in FIG. 1 to practice the principles of the invention. For example, it is possible to eliminate the respective network systems 110 and 160 and correspondingly, communicate survey questions to and receive responses from e-mail enabled computers of service provider and client representatives using conventional e-mail techniques. In a similar manner, the method of the present invention can also be implemented using computers of service provider and client representatives that have access to the Internet whereby the survey questions are provided and responses gathered by an interactive web-page.
Further, in accordance with the invention, it is not critical for the functions of the survey computer 135 to be performed by a stand-alone computer as depicted in the configuration 100 . It is possible for such functions to be implemented on a computer performing other operations for the service provider with the corresponding database 140 residing in memory of such computer.
FIG. 2 is an exemplary flow diagram 200 of an improved survey method in accordance with the invention. The steps of the flow diagram 200 in FIG. 2 will be described with respect to the configuration 100 of FIG. 1 . In step 210 , a particular set of survey questions is developed and communicated by the survey computer 135 to certain service provider representatives that use the computers 120 and 125 and have provided or are providing services to the client to be surveyed, or that have specific knowledge regarding the services or support provided by the service provider to such client. The responses to such survey questions entered by the service provider representatives into the computers 120 and 125 are communicated to the survey computer 135 . Step 220 illustrates the receipt of these responses by the survey computer 135 .
In step 230 , the received responses are analyzed by, for example, a survey administrator or management individual or team of a service provider, to identify whether development of a modification or remedial plan may be beneficial for one or more areas of service or support provided by the service provider to the client. Also, it is possible for the responses to the survey questions to be in a form that enables the survey computer 135 or another computer to process such responses to identify those areas of service or support for which modification or remedial plan may be beneficial. In particular, it is advantageous to employ numerical value scores to represent the responses to the survey. For example, it is possible to have the survey taker enter or select numerical values for survey questions. In the alternative, numerical values can be assigned to corresponding non-numerical responses regarding respective levels of satisfaction.
Based on the analysis in step 230 a decision is made in step 240 as to whether a modification or remedial plan will be developed. If the survey results indicate that a plan is not required then the method proceeds to step 270 . In step 270 , a client survey is developed and communicated by the survey computer 135 via the network servers 115 and 165 and Internet or e-mail network 150 to client representatives using the computers 170 , 175 and 180 as described in greater detail below. In the alternative, if, in step 240 , the analysis indicates that a modification or remedial plan would be beneficial for certain services provided to the client by the service provider then the method proceeds to step 250 .
In step 250 , a modification or remedial plan is developed for modifying or altering certain services or the manner in which such services or support are provided to the client. Then, in step 260 , the plan is presented by service provider representatives to client representatives including at least one of the representatives using a corresponding one of the computers 170 , 175 or 180 . The manner in which such plan is presented is not critical to the present invention. Accordingly, it is possible for the service provider to present this plan in an on-line presentation or via telephone or video conference or at in person presentation.
After the plan is presented to the client in step 260 , a client survey is developed and communicated by the survey computer 135 via the network servers 115 and 165 and Internet or e-mail network 150 to client representatives using the computers 170 , 175 and 180 as is illustrated in step 270 . The client survey may be developed by creating survey questions and, for example, multiple choice response options. In the alternative, such questions and response options may be selected from previously created survey questions and corresponding response options contained in the database 140 .
The developed client survey should contain questions that address the provided services and support by the service provider as well as how such service or support will be effected by implementation of the presented modification or remedial plan. Responses to such client survey questions are entered by the client representatives into computers 170 , 175 and 180 which communicate these responses to the survey computer 135 . As is previously described with respect the service provider survey questions in step 240 , it is advantageous to employ numerical value scores to represent the responses to the survey. It is possible to have the survey taker enter or select numerical values for survey questions. In the alternative, numerical values can be assigned to corresponding non-numerical responses regarding respective levels of satisfaction.
Receipt of the client responses by the survey computer 135 is indicated in step 280 . Lastly, in step 290 , the responses are analyzed to provide feedback to the service provider regarding provided service and support as to the extent any proposed modification or remedial plan. As a consequence, with a single survey of the client according to the invention, the service provider will not only know the satisfaction of the client with the provided service or support, but will advantageously also know what satisfaction the client will likely have with the implementation of the proposed modification or remedial plan. Accordingly, the method of the invention will enable a service provider to more quickly adapt provided services and support to a client's specific needs with a reduced number of client surveys relative to conventional survey techniques. Conventional survey techniques would have disadvantageously required at least two surveys of a client over likely a longer period of time—one survey before a plan is developed and a second survey after the plan is implemented—to achieve similar results as the survey method according to the invention.
The steps of the method 200 in FIG. 2 were depicted as occurring in a specific order and sequence for illustration purposes only. It is possible to perform certain of these steps in a different order or simultaneously in accordance with the invention. For example, it would be possible to develop a portion or all of the surveys for the service provider representatives at any time prior to transmission of such survey questions to their intended recipients.
It is advantageous to employ survey questions having numeric response regarding the respective level of satisfaction of the client representative responding to the survey. In this manner, it is possible to easily calculate an average level of satisfaction of the client representatives responding to the survey. Moreover, in determining satisfaction level scores in respective areas of service and support important or less important to the client and/or service provider, such response values may be adjusted by corresponding weighting factors. Such weighting factor adjustment may be in the form of multiplying/dividing the response scores or averages with corresponding weighting factors to produce weighted scores. In certain instances, it may be beneficial to create an offset weighting factor adjustment for respective response values or averages by adding or subtracting by a weighting factor.
An exemplary analysis process 300 performed by the survey computer 135 to carry out the required analysis operations of the survey method 200 is depicted in FIG. 3 . In accordance with the analysis process 300 , the survey computer 135 buffers or stores data contained in received responses to the service provider representative surveys in the database 140 in step 310 . In a similar manner, the survey computer 135 then buffers or stores data contained in received responses to the client surveys in the database 140 as indicated in step 320 . Lastly, in step 330 , the survey computer 135 processes the respective buffered response data by at least comparing directly or indirectly certain respective data buffered in steps 310 and 320 . An advantage gained by comparing the service provider representative survey responses and the client survey responses include identifying, quantitatively, those areas of mismatch between services and value. More specifically, the service provider may perceive that it is delivering an adequate level of service and therefore, continue to provide such service without modification based on such perception. However, in contrast, the client may view the level of delivered services differently even though such client has not previously expressed dissatisfaction. Accordingly, the invention further facilitates normalization of respective perceptions between the service provider representatives and the client regarding the actual client satisfaction.
In accordance with another aspect of the invention, it is advantageous to employ service-based questions and value-based questions in the client survey developed in step 270 of the method 200 in FIG. 2 . As used herein, service-based questions elicit feedback regarding expectations on contracted for services and the actual services provided. These questions reflect how well service provider delivers its contractual commitments. Value-based questions elicit feedback regarding intangible benefits the service provider provides relating to clients business objectives beyond contracted service. Value-based questions measure how well areas service provider's provided service correlate with the clients' business goals and the level that such service contributes to the client's success. Accordingly, responses to value-based survey questions are indicators of the extent of a client's dependence on its service provider for achieving such business success.
It is further advantageous in accordance with this aspect of the invention to process and/or analyze responses to the service-based and value-based questions in a manner to create a corresponding service-value index. An illustrative service-value index is graphically depicted as index graph 400 in FIG. 4 . The graph 400 is divided into four quadrants, based on, for example, a 1-4 scale for illustration purposes only. It is possible for the depicted graph 400 , for example, to process and/or analyze the responses to survey questions to produce services-based and/or value-based weighted scores. As a consequence, a mean, median or any other statistical averaging could then employed on such weighted scores to determine a plot point relative to the services-based and value-based axes in the graph 400 .
It would then be possible to characterize the nature and quality of the services provided to the client as, for example, strategic partner, consultant, vendor or commodity, based on whether such graphed point appears in the following corresponding quadrants:
Strategic Partner: High Value (2.5-4.0), High Service (2.5-4.0) Consultant: High Value (2.5-4.0), Low Service (0-2.5) Vendor: Low Value (0-2.5), High Service (2.5-4.0) Commodity: Low Value (0-2.5), Low Service (0-2.5)
It should be readily understood that previously description of one particular manner for determining a service-value is for illustration purposes only and that numerous other techniques are useable to determine a corresponding service-value index in accordance with the invention including, for example, employing different scales, different weighting factors, different statistical analysis or omitting the use of weighting factors. It is further possible to employ different representations of a service-value index than graph 400 including three-dimensional or greater graph.
It is to be understood that the invention is not limited to the illustrated and described forms of the invention contained herein. By way of further example, the invention can be embodied as instructions for execution on a single computer, or by one or more general purpose computers executing such code. Providing the processes and functions or accessing the methods or processes when provided by others are specifically within contemplation of the invention. It will be apparent to those skilled it the art that various changes may be made without departing for the scope of the invention and the invention is not considered limited to what is shown in the drawings and described in the specification.
|
An improved survey method is disclosed for evaluating the satisfaction of a client with the services and support provided by a service provider. The survey method includes first surveying at least one representative of a service provider providing a service to a client. A plan is then developed for the client based on survey data from the service provider representative survey to address at least one aspect of the provided service requires changing. The developed plan is then presented to the client. A second survey is then taken of at least representative of the client based on performance of the service provider and the developed plan. The survey method advantageously exploits the knowledge of those service provider representatives that provide a service to the client for identifying advantageous modifications of the service or support areas before presenting the client with a survey. In such manner, such survey results would enable a service provider to more quickly implement a plan for service changes that would likely increase client satisfaction with a single or reduced number of client surveys.
| 6
|
[0001] This application claims the benefit of U.S. Provisional Application No. 60/557,853, filed Mar. 30, 2004.
TECHNICAL FIELD
[0002] This invention relates generally to a bellows structure for enclosing or covering slots through walls of a cotton module builder or packager, and more particularly, to bellows which prevent passage through, and compaction in, cotton in slots through walls of a cotton module builder or packager for movement of apparatus for distributing and compacting cotton within the module builder or packager.
BACKGROUND ART
[0003] Cotton harvesting machines having an on-board cotton module building capability, also known as a cotton packager, include a cotton compacting chamber in which the compacted cotton module is built, formed by a floor and upstanding walls. Supported within this cotton compacting chamber is cotton compactor apparatus supported for vertical upward and downward movement for compacting cotton received in the chamber into the lower region thereof, for forming the module. It is important for the thus formed cotton module to have a cohesive, unitary composition which will be free standing when unloaded from the cotton compacting chamber, and which will remain substantially intact when subsequently handled. In particular, it is desirable for the upstanding sides of the thus formed compacted cotton module to be firm and relatively smooth to facilitate the subsequent handling, and also the removal of the module from the compacting chamber.
[0004] As a result, it is desirable for the structure and driving apparatus supporting the compactor apparatus to be located outwardly or outside of the compacting chamber. Such support structure and driver apparatus could be located above the compactor apparatus. However, the overall height of cotton harvesting machines must be limited so as to be able to pass through storage building doorways and under bridges, utility lines, and other overhead obstructions when moving from field to field. Therefore, it is sought to provide support structure and actuating drivers outside of the side walls of the compacting chamber.
[0005] Reference in this regard, U.S. Pat. Nos. 6,530,199 and 6,536,197, wherein external driver apparatus for the movement of the compactor structure or apparatus include four fluid cylinders, arranged two on each side of the compacting chamber. Such cylinders are disclosed as being double cylinders, one of which is used to index the compactor apparatus upwardly as the height of the module is increased, and the other for moving the compactor apparatus downwardly from the indexed location against the cotton in the compacting chamber for compacting the cotton.
[0006] It is contemplated to provide supporting structure and drivers on the exterior sides or ends of a module builder or packager connected to compactor apparatus within the cotton compacting chamber of the module builder or packager, for effecting downward movement under pressure and upper movement of the compactor apparatus. To accomplish this, it is contemplated that structural members will extend through vertical slots in walls of the module builder or packager, connecting the external structure to the compactor apparatus within the compacting chamber. However, a problem that can arise is passage of cotton from the compacting chamber through the vertical slots or passages, and/or collection and compaction of the cotton in the slots, so as to inhibit movement of the connecting structure through the slots, and also removal of the compacted body of cotton or module from the chamber due to integration with the cotton compacted into the slots. Additionally, it is contemplated that the structural members extending through the slots may vary in orientation as a result of uneven movement and tilting of the compactor apparatus.
[0007] Thus, what is sought is structure for a compactor apparatus of a cotton module builder or packager including external support and driver elements, which provides the advantages and overcomes the problems set forth above.
SUMMARY OF THE INVENTION
[0008] What is disclosed is structure for compactor apparatus of a cotton harvester which provides the advantages and overcomes one or more of the disadvantages and problems set forth above.
[0009] According to a preferred embodiment of the invention, the compactor apparatus includes a frame to be disposed within the cotton compacting chamber of a cotton module builder or packager including one or more structural elements which are movable downwardly within the chamber against the cotton for compacting the cotton against the floor and walls of the chamber. The frame includes cross members, preferably at the front and rear ends of the chamber, which extend across the chamber and protrude outwardly therefrom through upwardly and downwardly extending slots or passages through the side walls defining the chamber. The ends of the cross members which protrude through the slots or passages on each side of the chamber are connected together by an exterior side structure so as to be jointly movable upwardly and downwardly within the slots or passages, such that the frame is correspondingly moved upwardly and downwardly within the interior of the compacting chamber. Importantly, to maintain the frame at a horizontal orientation within the compacting chamber, or at an orientation relative to the floor within a permissible range, the exterior side structure on each side of the compacting chamber is guided by at least one vertically extending guide member. The side structure and at least one guide member can include members cooperatively engageable during the movement of the side structure such as rollers or the like. The exterior side structure on each side of the compacting chamber is connected to the module builder by a suitable driver, such as a fluid cylinder or the like, for moving the exterior side structure, and the frame upwardly and downwardly as desired or required for compacting the cotton within the chamber.
[0010] The frame of the compactor apparatus located within the compacting chamber preferably includes, in addition to the structural elements for compacting the cotton, at least one cotton driver, such as an auger or the like, extending in a horizontal orientation, and actuatable for moving the cotton within the chamber for more evenly distributing it therein for forming a more even cotton module.
[0011] According to another preferred aspect of the invention, bellows are disclosed for disposition in slots through the walls of the cotton module builder or packager for operation in cooperation with cross members extending therethrough for prevent passage of cotton through the slots and compaction of cotton therein. The bellows can optionally include elements for connection to the compactor apparatus which allow some relative misalignment therebetween as a result of tilting movement of the compactor apparatus. Below the compactor apparatus, in the region of the compacting chamber in which the cotton is being compacted, the bellows have a rigid surface which faces the interior of the chamber, and is supported such that compacting forces will not compress or deform the bellows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a side view of a cotton harvesting machine having an on-board cotton module builder including compactor apparatus according to the present invention thereon;
[0013] FIG. 2 is an enlarged fragmentary side view of the harvesting machine of FIG. 1 showing the compactor apparatus of the invention in an uppermost position;
[0014] FIG. 3 is another enlarged fragmentary side view of the harvesting machine of FIG. 1 showing the compactor apparatus in a lowered, compacting position;
[0015] FIG. 4 is an enlarged fragmentary top view of the module builder and compactor apparatus;
[0016] FIG. 5 is still another enlarged fragmentary side view of the module builder and exterior side structure and a guide member of the apparatus, showing rollers for controlling and guiding movement of the side structure along the guide member;
[0017] FIG. 6 is a simplified schematic perspective representation of the compactor apparatus of the invention in a raised position;
[0018] FIG. 7 is another simplified schematic perspective representation of the compactor apparatus of the invention in a lowered position;
[0019] FIG. 8 is an enlarged fragmentary side view of the front end of the module builder, showing bellows according to the invention in the vertical slot of the module builder;
[0020] FIG. 9 is a sectional view along line 9 - 9 of FIG. 8 ;
[0021] FIG. 10 is an enlarged fragmentary top view of the bellows of FIG. 8 ;
[0022] FIG. 11 is a side view of a guide frame of the bellows of FIG. 8 ;
[0023] FIG. 12 is an end view of the guide frame of FIG. 11 ;
[0024] FIG. 13 is a top view of a cover member of the bellows of FIG. 8 ;
[0025] FIG. 14 is another side view of the bellows of FIG. 8 ;
[0026] FIG. 15 is a side view of a guide frame for a rear bellows of the invention; and
[0027] FIG. 16 is an end view of the guide frame of FIG. 15 .
DETAILED DESCRIPTION OF THE INVENTION
[0028] Referring now to the drawings, in FIGS. 1, 2 , 3 and 4 , a cotton harvesting machine 10 is shown, including an on-board cotton module builder 12 , including compactor apparatus 14 . Generally, cotton harvesting machine 10 is self-propelled for movement over a field of cotton plants, and includes a plurality of cotton harvesting units 16 extending in a side-by-side array across a front end 18 of machine 10 . Cotton harvested by harvesting units 16 is conveyed by flows of air through ducts 20 which extend rearwardly and upwardly from harvesting units 16 to an upper region of a cotton compacting chamber 22 of module builder 12 , in the well known conventional manner. The cotton conveyed into cotton compacting chamber 22 will then collect on a floor 24 within chamber 22 , against which the cotton will be compacted by compactor apparatus 14 , as will be explained.
[0029] Cotton compacting chamber 22 is a four-sided cavity defined on the bottom by floor 24 and upwardly extending opposing front and rear end walls 26 and 28 , and side walls, represented by side wall 30 , extending therebetween. Walls 26 , 28 and 30 typically include openings or perforations therethrough, to allow passage and dissipation of the air used to convey the cotton into chamber 22 , while retaining the cotton therein. The upper region of cotton compacting chamber 22 of module builder 12 is enclosed by a roof 32 which can also include openings or perforations for the passage of air but not cotton therethrough. Importantly, the side walls, as represented by side wall 30 , each include a vertical forward slot 34 adjacent front end wall 26 , and a vertical rearward slot 36 adjacent rear end wall 28 , slots 34 and 36 extending substantially the entire vertical height of the compacting chamber.
[0030] Referring also to FIG. 4 , compactor apparatus 14 of module builder 12 includes a compactor frame 38 which is generally horizontal and substantially entirely disposed within cotton compacting chamber 22 , for movement downwardly against cotton contained therein for compacting the cotton against floor 24 . Compactor frame 38 includes a front cross member 40 disposed in chamber 22 adjacent front end wall 26 , and having opposite ends which extend through slots 34 . Similarly, a rear cross member 42 is disposed in chamber 22 adjacent rear end wall 28 and has opposite ends extending through slots 36 . A plurality of front and rear extending members 44 extend between and connect front and rear cross members 40 and 42 . Additionally, preferably at least one, and most preferably, several augers 46 are supported for rotation on front and rear cross members 40 and 42 , and extend forwardly and rearwardly therebetween. Augers 46 can be rotated using any suitable commercially available drivers, such as a gear drive driven by a motor such as a fluid or electric motor, or directly by fluid or electric motors, as desired, f or distributing the collected cotton in chamber 22 as required or desired. In this regard, it is particularly desirable to distribute the cotton evenly with respect to the plane of floor 24 , such that the resultant compacted cotton module will have a substantially uniform height along its length and width.
[0031] Compactor frame 38 of compactor apparatus 14 is supported in compacting chamber 22 on each side by an exterior side structure 48 , each structure 48 including a substantially horizontal, forwardly and rearwardly extending main beam 50 which extends between and connects front and rear cross members 40 and 42 . Each side structure 48 additionally includes a pair of braces 52 which extend downwardly and at converging angles from front and rear cross members 40 and 42 , and which are connected together by a gusset 54 located spacedly below about the middle of main beam 50 . Here, it should be noted that compactor frame 38 located within compacting chamber 22 and exterior side structures 48 on the exterior of the side walls represented by side wall 30 are movable upwardly and downwardly together.
[0032] The upward and downward movement of exterior side structures 48 and compactor frame 38 is preferably achieved and controlled by drivers 56 extending, respectively, between gusset 54 of each exterior side structure 48 and a support frame 58 supported by and extending upwardly from a frame 60 of module builder 12 . Drivers 56 each preferably comprise a fluid cylinder which receives fluid under pressure from a suitable pressurized fluid source, such as a fluid pump of machine 10 , for moving exterior side structure 48 , and thus compactor frame 38 of compactor apparatus 14 , upwardly and downwardly as required or desired f or performing a cotton distributing and/or compacting operation. Each driver 56 includes a fluid cylinder 62 connected to support frame 58 and a rod 64 connected to gusset 54 of exterior side structure 48 .
[0033] In FIGS. 1 and 2 , rod 64 is shown in a retracted position in cylinder 62 such that exterior side structure 48 and compactor frame 38 are located at an elevated position. FIG. 3 shows rod 64 extended to a substantially extended position, to position side structure 48 and compactor frame 38 at a lowered position, representing about a maximum compacting position of compactor apparatus 14 .
[0034] Referring also to FIG. 5 , as noted above, it is a sought after feature of the present module builder 12 to form and produce complete cotton modules having a substantially uniform height over the front-to-rear and side-to-side extent thereof. Generally, the harvested cotton conveyed through ducts 20 into compacting chamber 22 will have a tendency to collect in the more rearward region of chamber 22 , such that distribution in a forward direction by augers 46 is typically required. However, the cotton, even though more evenly distributed within chamber 22 , can have various inconsistencies in density and other conditions which make various regions of the collected cotton more difficult or easy to compact relative to other regions. As a result, if the downward movement of compactor frame 38 is not restrained or controlled, compactor frame 38 can be tilted undesirably and lateral loads and stresses can be exerted against driver 56 , both in the forwardly and rearwardly, and side-to-side directions.
[0035] To limit lateral loading, and facilitate the even distribution and compaction of the cotton within cotton compacting chamber 22 by compactor apparatus 14 , each exterior side structure 48 includes upper guide roller assemblies 66 , and lower guide roller assemblies 68 , each of which rollingly engage and are movable upwardly and downwardly along vertical guide members 70 disposed at spaced locations adjacent each side of module builder 12 , for controllably guiding the upward and downward movement of side structures 48 and compactor frame 38 , for holding or maintaining compactor frame 38 in a substantial horizontal orientation as it compacts the cotton in chamber 22 . Guide members 70 are fixedly mounted to frame 60 by brackets 72 which comprise sleeves which receive the respective guide members 70 and hold them in upstanding position and orientation beside module builder 12 . Guide members 70 are fixedly mounted at the top to roof 32 of module builder 12 . Each guide member 72 is preferably maintained in such upstanding orientation and position in bracket 72 by a pin 74 , which can be removed to allow lowering guide members 70 with upper portions of module builder 12 , for reducing the overall height of machine 10 for transport on trucks and rail cars, and other purposes as desired or required.
[0036] Each upper guide roller assembly 66 includes a bracket 76 mounted to main beam 50 of exterior side structure 48 and is of bifurcated or U-shaped construction so as to receive a guide member 70 therethrough. Bracket 76 supports a pair of rollers 78 for rotation about forwardly and rearwardly extending axes on opposite sides of guide member 70 , for controlling or substantially limiting side-to-side movement of exterior side structure 48 , and thus compactor frame 38 . To facilitate contact between rollers 78 and guide member 70 , rollers 78 each preferably has a concave outer surface 80 which engages the guide member 70 .
[0037] Similarly, each lower guide roller assembly 68 includes a bracket 82 mounted to brace 52 of exterior side structure 48 and is of bifurcated or U-shape construction so as to receive a guide member 70 therethrough. Bracket 82 supports a pair of rollers 78 for rotation about side-to-side extending axis on opposite sides of guide member 70 , for controlling or substantially limiting forward and rearward movement of exterior side structure 48 , and thus compactor frame 38 . To facilitate contact between rollers 78 and guide member 70 , rollers 78 each preferably has a concave outer surface 80 which engages the guide member 70 .
[0038] Referring to FIG. 6 , a schematic representation of compactor apparatus 14 in a raised position above floor 24 is shown. Here, drivers 56 can be observed supporting exterior side structures 48 on opposite sides of compactor frame 38 , and the positions of guide members 70 relative to exterior side structures 48 is evident.
[0039] FIG. 7 is a schematic representation showing compactor apparatus 14 in a lowered, compacting position, with compactor frame 38 supported by drivers 56 and exterior side structures 48 . Again, the position of guide members 70 adjacent exterior side structures 48 is evident.
[0040] Referring again to FIGS. 1, 2 , 3 and 4 , to contain the cotton and prevent passage through and compacting of cotton in slots 34 and 36 , each slot 34 and 36 includes an upper bellows 84 which encloses the slot above cross member 40 or 42 , and a lower bellows 86 which encloses the slot beneath the cross member 40 or 42 constructed and operable according to the teachings of the present invention. Bellows 84 and 86 include elements movable with the respective cross member 40 and 42 , and retractable and extendible elements for varying the height of the bellows during the movement of the cross member. Lower bellows 86 additionally include an interior surface which faces compacting chamber 22 which is of substantially rigid construction, to prevent the forces of compaction from forcing the cotton into the slot.
[0041] Referring also to FIG. 8 , upper bellows 84 and lower bellows 86 in slot 34 at the front end of module builder 12 are shown, above and below front cross member 40 of compactor apparatus 14 , respectively. Here, cross member 40 is shown at a raised position, representative of a non-compacting position, such that upper bellows 84 are in a compacted or retracted state, and lower bellows 86 are in an extended state. Each of bellows 84 and 86 are contained in and guided for vertical movement by a pair of opposing vertically extending C-shape channels 116 telescopically received in guide channel portions 88 and 90 of a guide frame 92 mounted in occupying relation to slot 34 . Guide frame 92 is preferably mounted to frame 60 and front end wall 26 of module builder 12 , by a plurality of conventional fasteners, here including conventional bolts 94 . Upper bellows 84 preferably comprise commercially available bellows or way protectors, such as, but not limited to, those available under the Gortite tradename from A&A manufacturing, Inc. of New Berlin, Wis., USA. Upper bellows 84 have a lower portion 96 which is attached or connected to cross member 40 for upward and downward movement therewith as denoted by arrow A, and an upper portion 98 suitably attached or connected to module builder 12 such as to roof 32 so as to remain stationary as cross member 40 is moved upwardly and downwardly, such that bellows 84 will expand during the downward movement, and contract or retract during the upward movement, respectively, to occupy and cover the space between opposing channels 116 to prevent passage of cotton therethrough and accumulation of cotton therein.
[0042] Lower bellows 86 are preferably of different construction than upper bellows 84 , and instead include a rigid, box shape cover member 100 having a sectional extent when viewed from above only marginally smaller than the space defined between C-shaped guide channels 116 so as to be cooperatively slidable therebetween in covering relation to the space.
[0043] Referring to FIGS. 11 and 12 , guide channels 88 and 90 of guide frame 92 are connected by lower intermediate panel 102 on the side which faces cotton compacting chamber 22 . Intermediate panel 102 is shorter in height compared to guide channels 88 and 90 , to thereby form an opening 104 between the guide channels above intermediate panel 102 . Cover member 100 and C-shaped channels 116 are telescopically received between guide channels 88 and 90 , such that cover member 100 can slide up and down within C-shaped channels 116 that are contained within guide channels 88 and 90 , between a position extending upwardly therefrom in covering relation to opening 104 , and a lower position wherein all or a portion of cross member 40 will be located in opening 104 . In this way, a rigid, pressure resistant structure is provided in covering relation to slot 34 which will prevent passage of cotton therethrough and entry of cotton therein during the compaction process.
[0044] Cover member 100 is preferably connected to a lower end of cross member 40 by a linkage arrangement 106 including a link 108 having an upper end pivotally connected to cross member 40 , and a lower end pivotally connected to cover member 100 . This is desirable as cross member 40 can be subjected to loadings which can cause it to tilt or rotate within the space between guide channels 88 and 90 , as denoted by arrows B, which movements are not desired to transferred to cover member 100 . This is advantageous as it allows the front-to-rear extent and sideward extent of cover member 100 to be only marginally smaller between those extents of the space defined between opposing channels 116 , such that there is less space therebetween for passage or collection of cotton.
[0045] Referring also to FIGS. 9 and 10 , which are each a top view of lower bellows 86 , angle brackets 110 for attachment of guide frame 92 to frame 60 by bolts 94 is better shown. Angle brackets 112 and 114 for attachment to front end wall 26 at side wall 30 are also shown. C-shape channels 116 are also shown telescopically disposed within guide frame 92 and 88 at the opposite ends thereof and define the interface with cover member 100 . As noted above, channels 116 also serve as guide channels for containing and guiding the upward and downward movement of upper bellows 84 . Channels 116 can attach to roof 32 and move downwardly therewith, so as to be more telescopically received in guide frame 92 and 88 when roof 32 is lowered f or transport.
[0046] Referring also to FIG. 13 , which is a bottom view of cover member 100 , outer surfaces of that member which oppose inner surfaces of channels 116 and inner surface of 102 in guide support 92 , include longitudinally extending strips 118 of a low friction polymer material to facilitate movement of member 100 in telescopic relation to channels 116 and guide frame 92 , and also to block passage of cotton between member 100 and the other components.
[0047] Referring also to FIG. 14 , linkage arrangement 106 is better shown, including brackets 120 which connect to cover member 100 at the bottom and cross member 40 at the top for pivotally connecting those members together. Brackets 120 can be attached directly to cross member 40 , and to an end closure 122 which is suitably connected such as by fastening or welding in closing relation to the upper end of cover member 100 .
[0048] It should be noted that upper and lower bellows 84 and 86 at the rear of module builder 12 are constructed essentially in the above-described manner, and are retained in position and guided by similar guide frames.
[0049] Referring also to FIGS. 15 and 16 , a representative guide frame 124 for bellows 86 at the rear are shown, including guide channels 88 and 90 defining a space therebetween for receiving C-shape channels 116 for guiding and controlling upward and downward movement of bellows 84 and 86 , and also an intermediate panel 102 on the side facing cotton compacting chamber 22 which does not extend the full height of the guide frame, so as to provide an opening 104 for receiving rear cross member 42 . Guide frame 124 is attached to rear end wall 128 of the module builder and side wall 30 , and frame 60 , in the above-described manner.
[0050] Here it should be noted that the bellows structure described herein has utility for a wide variety of other compactors, module builders and packagers and other structures, such as those disclosed in the above-referenced U.S. Pat. Nos. 6,530,199 and 6,536,197, and therefore is not intended to be limited to use with the structure described herein.
[0051] It will be understood that changes in the details, materials, steps, and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention. Accordingly, the following claim are intended to protect the invention broadly as well as in the specific form shown.
|
Bellows structure for a cotton module builder or packager, for enclosing or covering slots or passages through walls of a cotton module builder, for preventing entry of cotton into the slots or passages, to allow free movement of cross members therethrough of apparatus for distributing and compacting cotton within the module builder. The bellows can include telescoping rigid members below the cross members, and more flexible bellows thereabove.
| 0
|
TECHNICAL FIELD
The present invention relates to a wiper system, and in particular to a wiper system which can variably control its wiping angle.
BACKGROUND OF THE INVENTION
Some of the conventional wiper systems for vehicles such as automobiles can change the speed of the movement of the wiper depending on the intensity of rain fall. If the rain fall is substantial, the wiping speed is increased, and vice versa. Some wiper systems are provided with the intermittent operation mode in which the wiper system is activated in an intermittent manner. This mode is useful when there is minimal rain fall.
In an automobile equipped with such a wiper system, the speed of the wiper movement can be reduced in low speed range and increased in high speed range so that the optimum control of the wiper can be achieved in accordance with the vehicle speed.
When the vehicle is travelling at a high speed, the wind blows against the windshield at a high speed, and it is thus conceivable to reduce the wiping angle so that the force required for the movement of the wiper may be reduced, and, for instance, Japanese patent laid open publication (kokai) No. 02-136357 discloses such a wiping angle varying device. By thus allowing the wiping angle to be varied, it is possible to achieve an optimum wiping result at each vehicle speed.
However, according to such a conventional wiping angle varying device, the varying of the wiping angle may be required to take place during the wiping movement. Therefore, the motor which, for instance, consists of an electric motor is required to be powerful enough to change the wiping angle without being hindered by the force acting upon the wiper arm for the purpose of driving the wiper arm into the wiping movement by overcoming the frictional force which the wiper arm experiences. As a result, the wiper system tends to be bulky, and create problems in designing its mounting arrangement.
BRIEF SUMMARY OF THE INVENTION
In view of such problems of the prior art, a primary object of the present invention is to provide a wiper system equipped with means for changing the wiping angle which is compact in size.
A second object of the present invention is to provide a wiper system equipped with means for completing the process of changing the wiping angle without requiring an excessively bulky drive structure.
According to the present invention, such an object can be accomplished by providing a wiper system, comprising: wiper motor means; a wiper arm having a base end pivotally supported by a vehicle body and a free end carrying a wiper blade; linkage means for transmitting movement of an output end of the wiper motor means to the wiper arm so as to achieve a desired wiping movement of the wiper blade; and a wiping angle varying assembly included within the linkage means for varying the range of angle of the wiping movement of the wiper blade; the wiping angle varying assembly comprising actuator means, eccentric cam means provided in a path of transmitting the movement of the output end of the motor to the wiper arm, and control means for activating the actuator means so as to move the eccentric cam means and thereby change the range of angle of the wiping movement by altering a configuration of the linkage means; the control means activating the actuator means only when a first force transmitted through the linkage means from the wiper motor means to the wiper arm does not substantially oppose a second force produced by the actuator means to move the eccentric cam means.
Preferably, the control means activates the actuator means with such a timing that the first force transmitted through the linkage means from the wiper motor means to the wiper arm tends to assist the second force produced by the actuator means to move the eccentric cam means.
Thus, the actuator means is not required to overcome the first force produced by the wiper motor means to achieve a desired change in the configuration of the linkage means. As a result, the actuator means may consist of a relatively small motor, and can quickly achieve the desired change in the configuration of the linkage means.
According to a preferred embodiment of the present invention, there are a pair of wiper arms each pivotally supported by the vehicle body at a base end thereof and carrying a wiper blade at a free end thereof; and the linkage means comprises; a first pivot lever pivotally supported by the vehicle body, the base end of a first one of the wiper arms being integrally connected to the first pivot lever; a second pivot lever pivotally supported by the vehicle body, the base end of a second one of the wiper arms being integrally connected to the second pivot lever; a first connecting rod having a first end connected to an output end of the wiper motor means and a second end pivotally connected to a free end of the first pivot lever via joint means; and a second connecting rod having a first end connected to a free end of the first pivot lever and a second end pivotally connected to a free end of the second pivot lever; the joint means being adapted to be moved toward and away from a center of rotation of the first pivot lever by the actuator means and the eccentric cam means.
The term "eccentric cam means" used herein should be understood in its broadest meaning, and includes not only eccentric cams but also all other mechanical or other means which act between two members of the linkage means and are subjected to the force transmitted from the wiper motor means to the wiper arms when achieving the required change in the linkage means.
According to a particularly preferred embodiment of the present invention, the eccentric cam means and the joint means comprise a lever arm member pivotally secured to the first pivot lever, and a ball joint member secured to the lever arm member offset from a center of rotation of the lever arm member relative to the first pivot lever, the second end of the first connecting rod being coupled to the ball joint member. Furthermore, the first pivot lever is pivotally supported by the vehicle body via a hollow pivot shaft integrally attached to the first pivot lever, and the actuator means comprises an electric actuator motor coaxially received in the pivot shaft, an actuator arm member integrally secured to an output shaft of the actuator motor, and a link member having a first end pivotally connected to the actuator arm member and a second end pivotally connected to a part of the lever arm member spaced from a center of rotation of the lever arm member relative to the first pivot lever.
Thus, the actuator means can be conveniently incorporated in linkage means which is very similar to the conventional linkage for normal wiper systems.
Normally, the control means comprises a position sensor for detecting positions of the first pivot lever immediately before and after a reversal point at which the first pivot lever changes its direction of movement, and selectively activates the actuator means when the first pivot lever is immediately before or after the reversal point depending on a relationship between directions of the first and second forces.
BRIEF DESCRIPTION OF THE DRAWINGS
Now the present invention is described in the following with reference to the appended drawings, in which:
FIG. 1 is a diagram showing the variable range of the wiping angle of a wiper system to which the present invention is applied;
FIG. 2 is a partly broken away side view of a wiping angle varying assembly which is conveniently incorporated in the pivot lever according to the present invention;
FIG. 3 is a view seen from arrow III of FIG. 2;
FIG. 4 is a circuit diagram of the control unit for the present invention;
FIG. 5 is a view similar to FIG. 3 showing the pivot lever when the OFF/intermittent operation mode is selected;
FIG. 6 is a view similar to FIG. 3 showing the pivot lever when the low speed operation mode is selected;
FIG. 7 is a diagram showing the way in which the operation mode is switched over from the intermittent mode to the low speed/high speed mode;
FIG. 8 is a diagram showing the way in which the operation mode is switched over from the low speed mode to the high speed mode;
FIG. 9 is a diagram showing the way in which the operation mode is switched over from the low speed mode to the intermittent mode; and
FIG. 10 is a diagram showing the way in which the operation mode is switched over from the high speed mode to the low speed/intermittent mode.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a schematic view showing the variable range of the sweeping angle of the wiper system according to the present invention. FIG. 1 only shows the range of the sweeping angle for the driver's side, but the same thing applies to the passenger's side. The wiper arm 1 for the driver's side is actuated by a wiper motor 2 via a linkage mechanism so as to synchronize with the wiper arm for the passenger's side which is not shown in the drawing. When a crank arm 3 is rotatively driven by the wiper motor 3, a first pivot lever 5 is made to undergo an angular movement via a first connecting rod 4a, and a second pivot lever 6 is likewise made to undergo a similar angular movement via a second connecting rod 4b which is connected between the first pivot lever 5 and the second pivot lever 6. The wiper arms for the driver's side and the passenger's side integrally connected to the corresponding pivot levers 5 and 6 are thereby made to undergo the desired sweeping movement relative to a front windshield 7.
In this wiper system, it is possible to select three modes of operation, intermittent, low speed and high speed, and the sweeping angle for each of the operating modes is determined so that a desired sweeping range may be obtained in each of the operating modes. For instance, the sweeping range for the intermittent mode is the sector area I--I indicated by the solid lines, the sweeping range for the low speed mode is the sector area L--L indicated by the broken lines, and the sweeping range for the high speed mode is the sector area H--H indicated by the one-dot chain lines, the sweeping range thus being progressively narrowed as the operating speed is increased.
The mechanism for achieving such variable sweeping ranges is incorporated in the first pivot lever 5 provided in an intermediate part of the wiper system, and its structure is now described in the following with reference to FIGS. 2 and 3. The pivot lever 5 is rotatably supported by the vehicle body by way of a tubular pivot shaft 8 laterally and integrally extending from a base end of the pivot lever 5 and supported by the vehicle body via bearings 9. The pivot shaft 8 is coaxially provided with a wiper mounting shaft 8a on which an arm head of the wiper arm 11 for the passenger's side is mounted via a tapered serration coupling.
The pivot shaft 8 accommodates therein a wiping angle varying motor 12. The output torque of the wiping angle varying motor 12 is taken out via a speed reduction unit 13, and the pivot lever 5 is provided with a sector-shaped relay plate 14 which surrounds an intermediate part of an output shaft 13a of the speed reduction unit 13. Further, a disk-shaped crank member 15 is fixedly secured to a free end of the output shaft 13a of the speed reduction unit 13. A lever arm member 16 serving as an eccentric cam is pivotally attached to a free end of the pivot lever 5, and this lever arm member 16 is linked with the crank member 15 via a substantially L-shaped link rod 17.
A joint ball 18a for the first connecting rod 4a connected to the output end of the wiper motor 2 is provided in a part of the lever arm member 16 which is offset by a prescribed amount (indicated by r in the drawing) from the center of rotation of the lever arm member 16. As the wiping angle varying motor 12 rotates, the output shaft 13a of the reduction unit 13 rotates over a prescribed angle in either direction, and the resulting angular movement of the lever arm member 16 causes the joint ball 18a to move along a circular path of a radius R centered around the center of rotation of the lever arm member 16. FIGS. 2 and 3 show the case in which the wiper system is operating in the high speed mode, and the effective radius of rotation of the pivot lever 5 in this case is Rh as shown in FIG. 3. The link rod 17 and the lever arm member 16 are made to rotate in such a manner that the terminal point of the movement of the connecting point between the crank member 15 and the link rod 17 and that of the connecting point between the lever arm member 16 and the link rod 17 are indicated by H in the drawing in the case of the high speed mode, by L in the case of the low speed mode, and by I in the case of the OFF position and the intermittent mode. The side of the pivot lever 5, opposite to the side to which the joint ball 18a is connected, has a joint ball 18b of the second connecting rod 4b connected thereto.
FIG. 4 shows a circuit diagram of the control circuitry of the wiper system of the present invention, and its details are described in the following. A control unit 21 including a CPU and power transistors for effecting the control of the wiper system obtains its electric power from a battery BT via an ignition switch IG. The control circuit of the wiper system comprises, in addition to the control unit 21, a wiper switch 22 for selecting the operating mode of the wiper system, an intermittent relay 23 for achieving an intermittent operation, a wiper motor unit 25 consisting of the aforementioned wiper motor 2 and a position sensor 24 operating in association with the movement of the wiper motor 2, and a wiping angle varying unit 26 consisting of the aforementioned wiping angle varying motor 12 and the relay plate 14.
The wiper switch 22 comprises a switch unit SW1 having a pair of four-position selection contacts for selecting the OFF, intermittent, low speed and high speed operation modes, and a switch unit SW2 having a pair of two-position selection contacts for selecting the mist operation mode in which washer fluid is sprayed onto the windshield. The common terminal of one of the selection switches of the switch unit SW1 is connected to the normally closed terminal of one of the selection switches of the switch unit SW2, and the common terminal of the last mentioned selection switch and the normally closed terminal of the other selection switch of the switch unit SW2 are connected to the low speed drive terminal LO of the wiper motor 2. The B terminal or the power terminal of the wiper motor 2 is connected to the secondary end of the ignition switch IG.
The common terminal of the other switch of the switch unit SW1 is connected to the common terminal of the other selection switch of the switch unit SW2, and the node between them is connected to the high speed drive terminal Hi of the wiper motor 2. The selection contacts for the OFF and intermittent operation modes of the said one of the selection switch of the switch unit SW1 are connected to the common terminal of the switch RS of the intermittent relay 23. The normally open contact of the switch RS is grounded while the normally closed contact of the switch RS is connected to the corresponding terminal of the control unit 21. The low speed selection contact of the said one of the selection switches of the switch unit SW1, the high speed selection contact of the other selection switch of the switch unit SW1, and the mist selection contact of one of the selection switch of the switch unit SW2 are grounded.
The open terminals of the switch unit SW1 and SW2 shown in FIG. 4 are connected to the control unit 21 so that the control unit 21 may detect when any one of these contacts is selected although it is not shown in the drawing to avoid crowding the drawing. One end of the coil RL of the intermittent relay 23 is connected to the secondary end of the ignition switch IG, and the other end of the coil RL is connected to the corresponding terminal of the control unit 21.
The position sensor 24 of the wiper motor unit 25 comprises a rotary slider assembly 24a which integrally rotates with the motor shaft of the wiper motor 2, and fixed contacts 24b through 24g coaxially arranged along four concentric circles either in annular or arcuate configuration for detecting the prescribed positions of the wiper arm. The rotary slider assembly 24a is provided with four sliders which slide over the innermost annular fixed contact 24b, the large and small arcuate fixed contacts 24c and 24d surrounding the annular contact 24b, the outer annular fixed contact 24e surrounding the arcuate contacts 24c and 24d, and a pair of outermost arcuate fixed contacts 24f and 24g so that a desired state of conduction can be achieved between the fixed contacts 24b through 24g according to the way they are arranged.
The innermost contact 24b is connected to the node between the normally closed contact of the switch RS of the intermittent relay 23 and the connecting terminal of the control unit 21 corresponding thereto. The larger arcuate contact 24c immediately outside this contact is grounded while the smaller arcuate contact 24d corresponds to the point of reversal from the normal direction or positions for retracting the wiper arm and effecting the autostop, and is connected to the terminal B for power supply to the wiper motor 2. The contact 24e surrounding them is used as a common terminal, and is connected to a corresponding terminal of the control unit 21. The outermost contacts 24f and 24g extend on either side of a point of reversal from the reverse direction each over a certain range, and are connected to respective terminals of the control unit 21.
The two terminals of the wiping angle varying motor 12 are connected to a corresponding pair of drive output terminals of the control unit 21. A moveable contact assembly 14a is fixedly secured to the motor shaft of the wiping angle varying motor 12, and has three sliders which are adapted to contact the fixed contacts 14b through 14e of the relay plate 14 as the motor rotates. The contacts 14b through 14e are arranged in such a pattern that the OFF, intermittent, low speed and high speed operation modes can be selectively detected as the moveable contact assembly 14a moves.
The operation of the wiper system having the above described structure is now described in the following. When the switch unit SW1 is switched over from the OFF position illustrated in FIG. 4 to the intermittent position, the control unit 21 then detects the state of this switch unit and supplies an energization signal to the coil RL of the intermittent relay 23, and the switch RS thereof is grounded. At the same time, the low speed terminal LO of the wiper motor 2 is grounded via the switch units SW1 and SW2, and the wiper motor 2 is rotated at low speed. The control unit 21 then produces a signal which rotates the wiping angle varying motor 12 so as to place the moveable contact unit 14a at the OFF/intermittent position which is indicated by the solid lines in FIG. 4.
At the time of the intermittent operation, the 35 joint ball 18a is positioned as illustrated in FIG. 5, and its radius of rotation is Ri, as indicated in the drawing, which is smaller than Rh shown in FIG. 3. Thus, the wiping angle is enlarged for a given stroke of the connecting rod, and the wiping action covering the relatively large range I--I is accomplished as illustrated in FIG. 1. At the same time, the intermittent relay 23 is turned on and off at an interval determined by an intermittent time setting unit not shown in the drawing, and the intermittent wiping action of the wiper arm is carried out.
When the wiper switch 22 is moved to the low speed position, the wiping angle varying motor 12 is activated by the control unit 21 until it is detected that the moveable contact assembly 14a has moved to the low speed position according to the signal detected thereby. In this case, the joint ball 18a is positioned as illustrated in FIG. 6, and its radius of rotation is R1 as illustrated in FIG. 6 which is intermediate between the radius Rh of FIG. 3 and the radius Ri of FIG. 5. In this case, the wiping action of the wiper arm is made over the range L--L illustrated in FIG. 1 which is narrower than the range for the intermittent mode but wider than the range for the high speed mode.
When the high speed mode is selected, the wiping angle varying motor 12 is activated by the control unit 21 until it is detected that the moveable contact unit 14a has moved to the high speed position in the same way as described above. As a result, the radius of rotation Rh of the joint ball 18a is maximized (FIG. 3), and the wiping action of the wiper arm is made over the narrowest range H--H indicated in FIG. 1.
In the present embodiment, the timing of actuating the wiping angle varying motor 12 is selected so as to coincide with either immediately before or immediately after the point of reversal from the reverse movement. These points can be detected by using the aforementioned fixed contact pair 24f and 24g. More specifically, the point immediately before the point of reversal from the reverse movement is detected as the time when the moveable contact assembly 24a which rotates in clockwise direction as indicated by the arrow A in FIG. 4 is in contact with one of the fixed contacts 24f, and the point immediately after the point of reversal is detected as the time when the moveable contact assembly 24a is in contact with the other fixed contact 24g.
For instance, when the operating mode is to be switched from the intermittent mode to either the high speed or low speed mode, the switch over is effected immediately after the point of reversal as shown in FIG. 7. Because immediately after the point of reversal from the reverse movement the pulling force F1 exerted by the first connecting rod 4a on the joint ball 18a to rotate the pivot lever 5 in the direction indicated by the arrow B is directed to the right in the sense of the drawing, the lever arm member 16 is subjected to a moment M1 which tends to rotate the lever arm member 16 in the direction indicated by the arrow C indicated by the broken lines around its pivot axis. Likewise, when the wiping angle varying motor 12 is actuated as a result of a switch over from the intermittent mode to either the high speed or the low speed mode, the direction of rotation of the lever arm member 16 caused by the wiping angle varying motor 12 is as indicated by the arrow C. Therefore, the moment M1 can be used for rotating the lever arm member 16 in the direction of the arrow C, and the small output torque of the wiping angle varying motor 12 is therefore sufficient for rotating the lever arm member 16. As a result, the wiping angle varying motor 12 can be made compact enough, for instance, to be incorporated in the pivot shaft 8, and the freedom of layout design can be expanded.
FIG. 8 is a view similar to FIG. 7 showing the case in which the operation mode is switched over from the low speed mode to the high speed mode. When switching over from the low speed mode to the high speed mode, the direction of rotation of the lever arm member 16 caused by the wiping angle varying motor 12 is in the direction of the arrow C in the same way as in the previous instance, but the connecting point between the lever arm member 16 and the link rod 17 is located on the other side of the center of the joint ball 18a with respect to the center of rotation of the lever arm member 16. Therefore, the leftward pushing force F2 which tends to rotate the pivot lever 5 in the direction indicated by the arrow D in FIG. 8 acts upon the lever arm member 16 in such a direction as to rotate the lever arm member 16 in the direction indicated by the arrow C. Therefore, in this case also, the moment M2 arising from the pushing force F2 is conveniently used for rotating the lever arm member in the direction indicated by the arrow C.
FIG. 9 shows the case in which the operation mode is switched over from the low speed mode to the intermittent mode. In this case, since the lever arm member 16 is rotated by the wiping angle varying motor 12 in the direction indicated by the arrow E which is opposite to the cases shown in FIGS. 7 and 8, the moment M3 arising from the pulling force F1 transmitted from the first connecting rod 4a immediately after the point of reversal from the reverse movement is again conveniently used for the same purpose as described above.
FIG. 10 shows the case in which the operation mode is switched over from the low high speed mode to the intermittent/high speed mode. In this case, since the lever arm member 16 is rotated in the direction indicated by the arrow E by the wiping angle varying motor 12 in the same way as shown in FIG. 9, the moment M4 arising from the pulling force F1 transmitted from the first connecting rod 4a immediately after the point of reversal from the reverse movement is again conveniently used for the same purpose as described above.
In this embodiment, the timing of the switch over took place immediately before or after the point of reversal from the reverse movement, but the present invention is not limited by this arrangement. It is also possible to determine the angle of rotation of the pivot lever 5 and to arrange the relative positions of the lever arm member 16 and the joint ball 18a in such a manner that the switch over may take place immediately before or after the point of reversal from the normal movement, and to combine such timings.
Thus, according to the present invention, the direction of movement of eccentric cam means to change the wiping angle of a wiper system is made to coincide with that of the moment or the force applied by the wiper motor to the eccentric cam means, and the eccentric cam means is thereby allowed to be moved with a relatively small drive force or torque. As a result, the eccentric cam means can be easily actuated even when the drive force or torque available for driving the eccentric cam means is small, and a relatively small motor can be used for driving the eccentric cam means. As a result, the actuating motor may be made compact in size, and the freedom of layout design can be increased.
Although the present invention has been described in terms of a specific embodiment thereof, it is possible to modify and alter details thereof without departing from the spirit of the present invention.
|
To allow compact design of a wiper system equipped with a wiping angle varying assembly which comprises an actuating motor, an eccentric cam member provided in a path of transmitting the movement of the output end of a wiper motor to a wiper arm, and a control unit for activating the actuating motor so as to move the eccentric cam member and thereby change the range of angle of the wiping movement by altering a configuration of a linkage structure provided between the wiper motor and the wiper arm, the control unit is adapted to activate the eccentric cam member with such a timing that the force transmitted through the linkage structure from the wiper motor to the wiper arm tends to assist the force produced by the actuating motor to move the eccentric cam member in the required direction. Thus, the requirement of the power output of the actuating motor can be reduced, and the actuating motor can be substantially reduced in size. As a result, the design of the wiping angle varying assembly is simplified, and the assembly may be conveniently incorporated in a linkage structure similar in structure to the conventional linkage structure for wiper systems not equipped with any wiping angle varying assembly.
| 8
|
TECHNICAL FIELD
[0001] The present invention relates to a phantom for displaying a treatment area of ultrasonic wave radiated from an ultrasonic device used for measurement, diagnosis, treatment, and the like, and to a device for carrying out calibration of the ultrasonic device.
BACKGROUND ART
[0002] Recently, in treatment of diseases, Quality of Life of a patient who underwent operation has been considered to be important. Even in such heavy diseases as cancers, social needs for treatment methods with lower invasiveness than conventionally have been required. Currently, low invasive treatment mainly used clinically includes treatment such as endoscopic operation, laparoscopic operation, which includes insertion of a tubular guide into a body, or treatment such as radio frequency ablation treatment, which includes insertion of a needle-like treatment device into a body, any of which are accompanied with invasiveness of devices. On the contrary, ultrasonic waves can be converged in a region having a size of 1 cm×1 cm or less in a body from the outside of the body without inserting a device into the body, based on the relation between the wavelength and the attenuation in the body. By using the characteristics, clinical applications of low invasive ultrasonic treatment methods have been started. Ultrasonic treatment which is the most used clinically at present is High Intensity Focused Ultrasonic (HIFU) treatment subjected to uterine fibroid and breast cancer, which ablates an affected site tissue by raising a temperature of the affected site by irradiation with HIFU to at temperature equal to or higher than a coagulation temperature of protein for several seconds.
[0003] In treatment using an ultrasonic wave, since an ultrasonic wave generator is not brought into contact with a treatment region, it is necessary to monitor a region at which treatment is carried out by using a diagnostic imaging device, or the like. Furthermore, in order to carry out selective treatment more reliably, in addition to the monitoring, it is also important to schedule a treatment plan in advance, and to control the amount of ultrasonic waves so that the treatment region is irradiated with an appropriate amount of ultrasonic waves and that regions other than the treatment region is not irradiated with an inappropriately excessive amount of ultrasonic waves.
[0004] Important steps of the treatment plan in the ultrasonic treatment include verification of whether or not a device in which setting for treatment is carried out works as expected. Such verification can be achieved before application to a human body by irradiating an ultrasonic phantom (tissue mimicking phantom), which has been configured so as to be able to simulate a living body, to display the extent and range of the biological effect generated by ultrasonic irradiation inside thereof, with ultrasonic wave, and observing and analyzing the results.
[0005] As the above-mentioned ultrasonic phantom, one for visualizing not energy of an ultrasonic wave itself but a secondary effect generated by an ultrasonic wave is mainly used. Examples thereof include a phantom shown in NPL 1, which uses soluble protein as an indicator agent and detects temperature rise due to irradiation with an ultrasonic wave. This phantom uses the phenomena that when protein undergoes heat denaturation, the protein is coagulated and molecules are aggregated to each other, and scattering intensity is increased to cause optical change as compared with before the denaturation, in particular, whitening occurs.
CITATION LIST
Non-Patent Literature
[0000]
NPL 1: C Lafon et al. Proc. IEEE Ultrasonics Symposium pp. 1295-1298 (2001)
SUMMARY OF INVENTION
Technical Problem
[0007] A conventionally used tissue mimicking phantom for HIFU treatment detects the protein appearance change from translucent to opaque due to denaturation by visual check or an optical technique. However, there is a problem that the phantom cannot carry out controlling of ultrasonic intensity in which the optical change occurs, as well as controlling of optical turbidity and nucleus of cavitation, independently. That is because determination of the strength of ultrasonic intensity necessary for optical change is carried out inclusively based on the effect as a criteria of buffers such as lower alcohol and tris-(hydroxymethyl)-aminomethane (hereinafter, which is abbreviated as “Tris”), or the like. Specific buffers such as lower alcohol and Tris change a three-dimensional structure of bovine serum albumin and deteriorates dissolution stability in a solution. Therefore, albumin forms an aggregated body, but such an aggregated body is in a semi-denatured state. When temperature is increased due to ultrasonic irradiation or the like, the aggregated body of albumin is more susceptible to denaturation as compared with a simple substance of albumin. Such an effect that denaturation of protein easily occurs by ultrasonic irradiation is remarkably found in Tris. However, a protein solution including an aggregated body has higher turbidity than a solution in a state in which protein completely dissolved, which poses a problem when a phantom having a particularly large size is prepared.
[0008] Furthermore, the protein in such an aggregated body state works as nucleus of acoustic cavitation mentioned below, but since the phantom includes a region in which an aggregated body is generated and a region in which an aggregated body is not generated, nuclei are scattered, and as a result, denaturation is not generated uniformly in the phantom. Furthermore, since Tris or lower alcohol is a low molecule, there is a problem that Tris or lower alcohol has a property of easily passing through a network structure of hydrogel as base material of an tissue mimicking phantom, so that Tris or lower alcohol easily leaks out from the phantom. Therefore, as in, for example, a phantom-bed integral type large ultrasonic irradiation device, when it is necessary to use a phantom in a state in which it is brought into direct contact with an ultrasonic device, the component concentration is changed over time. Therefore, it is highly likely that properties as the phantom may be deteriorated.
[0009] Note here that an acoustic cavitation denotes a phenomenon in which minutes air bubbles are generated from a substance as a nucleus generated by irradiation with respect to liquid, organisms, or the like, with ultrasonic waves, is grown and finally collapsed by ultrasonic vibration.
Solution to Problem
[0010] In order to solve the above-mentioned problem, an tissue mimicking phantom in accordance with the present invention is characterized by including an indicator agent which is denatured by temperature rise to simulate the effects of ultrasonic treatment, and a denaturation sensitivity controlling agent which is a different component from the indicator agent and which serves as a nucleus of cavitation and supports the temperature rise and the denaturation of the indicator agent at the time of irradiation with ultrasonic waves.
Advantageous Effects of Invention
[0011] According to the ultrasonic phantom of the present invention, it is possible to independently control a degree at which optical changes occur by the irradiation with ultrasonic waves, optical transparency before the irradiation with ultrasonic waves, and a degree of serving as the nucleus of cavitation at a time of ultrasonic irradiation. Calibration of the strength of an ultrasonic treatment device can be carried out more stably than conventionally possible. Furthermore, the ultrasonic phantom of the present invention can be used in a state in which the phantom is taken out from a container and is closely brought into direct contact with an ultrasonic irradiation device. Thus, there is little limitation in usage forms.
BRIEF DESCRIPTION OF DRAWINGS
[0012] FIG. 1 is a view showing an experimental system in which verification of effects of a denaturation sensitivity controlling agent for tissue mimicking phantom is carried out in accordance with the present invention.
[0013] FIG. 2 is a view showing an experimental system in which verification of effects of the tissue mimicking phantom is carried out in accordance with the present invention.
[0014] FIG. 3 is a view showing one example of an optical image after the tissue mimicking phantom is irradiated with convergent ultrasonic wave in accordance with the present invention.
[0015] FIG. 4 is a graph showing one example of a change in a denatured region when irradiation with a focused ultrasonic wave is carried out with the intensity varied in a state in which a temperature of the tissue mimicking phantom is kept at 37° C. in accordance with the present invention.
[0016] FIG. 5 is a graph showing one example of a change in a denatured region when irradiation with a focused ultrasonic wave is carried out with the intensity varied in a state in which a temperature of the tissue mimicking phantom is kept at 25° C. in accordance with the present invention.
[0017] FIG. 6 is a graph showing one example of a difference in the denatured region when irradiation with a strongly focused ultrasonic wave is carried out in a state in which a temperature of the tissue mimicking phantom prepared while a serum the concentration of albumin is changed is kept at 37° C. in accordance with the present invention.
[0018] FIG. 7 is a view showing an outer frame of ultrasonic phantom in accordance with one Example of the present invention.
[0019] FIG. 8 is a view showing a gel of a phantom main body of the ultrasonic phantom in accordance with one Example of the present invention.
[0020] FIG. 9 is a view showing one example of a calibration device of an ultrasonic treatment device which is used in combination of the ultrasonic phantom of the present invention.
[0021] FIG. 10 is a view showing one example of effect verification of a denaturation sensitivity controlling agent for an tissue mimicking phantom in accordance with the present invention.
DESCRIPTION OF EMBODIMENTS
[0022] In a conventional ultrasonic phantom, it was difficult to control the sensitivity at which denaturation occurs when irradiation with an ultrasonic wave is carried out, optical turbidity, and an effect as a nucleus of cavitation independently. This is because a component to be denatured is in a metastable state, thus improving sensitivity, with the effects of Tris and lower alcohol, when irradiation with an ultrasonic wave is carried out, but this metastable state increases optical turbidity and has an effect as a nucleus of cavitation. Furthermore, in such an existing phantom, since low molecules such as Tris are used for expressing the effects, the above-mentioned three effects easily disappear due to flowing of the low molecules such as Tris from the inside of the phantom having a gel form. Thus, the existing phantom lacks in stability over time.
[0023] From these viewpoints, we have devised a method of allowing a phantom to additionally contain material, which has a property that is substantially the same as in a state in which the component generating denaturation becomes a metastable state by the presence of Tris or the like, as a denaturation sensitivity controlling agent, in addition to the component generating denaturation when irradiation with ultrasonic waves is carried out, instead of using material which directly acts on a component, typically Tris, generating denaturation when irradiation with an ultrasonic wave is carried out. In particular, unlike conventional phantom, by using not a low molecule but a high molecule, phantom, which has taken stability over time into account, is achieved.
[0024] Specifically, the phantom is configured by including, as a denaturation sensitivity controlling agent, a high molecular compound whose turbidity in the wavelength of 600 nm when it is dispersed at 1 gram per 1 liter in a pure water and in a neutral state becomes 0.001 or more and 0.1 or less per 1 cm. The use of such a method can dissolve a problem that the turbidity of a phantom as a whole is increased when metastable state protein is used as conventionally.
[0025] As a result of study, as the high molecular compound used as the denaturation sensitivity controlling agent, we found that protein having low solubility in water, or protein whose solubility in water is lowered by pretreatment is preferred. More specifically, we have found that egg white albumin, milk albumin, globulin in general having lower solubility in water than that of serum albumin satisfy the purpose. Furthermore, regardless of the solubility in water, we have found that water-soluble protein, which was subjected to heat treatment, or ultrasonic treatment, or radiation irradiation in advance, satisfy the purpose.
[0026] Hereinafter, Test Examples and Examples of the present invention are described specifically, but the present invention is not limited to these Examples.
[0027] Firstly, in order to search material to be used as the denaturation sensitivity controlling agent, an effect of generating cavitation when the material is dispersed in water and irradiation with an ultrasonic wave is carried out is measured by using an experimental system shown in FIG. 1 . An acrylic water tank 1 is filled with degassed water 2 , the water temperature is kept at 37° C. by using a water temperature adjuster and a thermometer which are not shown in the drawing. In the water tank, a sample 101 is fixed at a focus position of convergent ultrasonic wave transducer 5 by a holder 4 in a state in which the sample 101 is dispersed in water in the tank and placed in a polyethylene bag having thickness of 0.03 mm.
[0028] The transducer 5 is connected to a waveform generator 6 and signal amplifier 7 . Furthermore, in order to verify the position of the sample 101 , an ultrasonic diagnostic device 8 and a diagnostic probe 9 are provided in the water. Furthermore, an acoustic signal generated from the sample 101 by ultrasonic irradiation is measured by using a hydrophone 100 , and the acoustic signal is stored in an oscilloscope 102 . The waveform generating device 6 , the ultrasonic diagnostic device 8 , and the oscilloscope 102 are connected to a control oriented computer 11 , and set so that the acoustic signal taken by a hydrophone 100 in synchronization with ultrasonic irradiation from the waveform generating device 6 .
[0029] FIG. 10 shows a signal strength taken by the hydrophone 100 as an indicator of cavitation strength when a concentration of a sample is changed with respect to the turbidity in the wavelength of 600 nm as a an indicator. As the sample, titanium oxide fine particles, egg albumin, milk albumin, blood globulin, and serum albumin that had been treated in the ultrasonic washer for two minutes were used. From the drawing, an acoustic signal is returned from the samples except for titanium oxide, showing that the samples serve as the nucleus of cavitation. Furthermore, in the samples other than titanium oxide, it is shown that an effect when the turbidity is 0.001 or more.
[0030] Furthermore, each sample was prepared in a thickness of 2 cm, and a chicken breast meat piece, which had been cut in a size of 1 cm 3 , was disposed behind the sample. Then, when it was verified whether or not the shape of the chicken breast meat piece was able to be determined, it was shown that the shape was able to be clearly determined when the turbidity was not more than 0.1 per 1 cm.
[0031] Considering the above-mentioned experimental fact and considering that a denaturation indicator agent of the present invention is serum albumin having a concentration of about 10% and that the concentration of the denaturation sensitivity controlling agent is desirably not more than one-tenth of that of the denaturation indicator agent so that denatured regions are not spotted, it is desirable that the concentration of the denaturation sensitivity controlling agent is not more than about 1%. Thus, it is shown to be desirable that in the denaturation sensitivity controlling agent of the present invention, the turbidity in the wavelength of 600 nm is not more than 0.001 and not less than 0.1 when 10 gram per liter is dispersed.
[0032] Subsequently, an tissue mimicking phantom including serum albumin as a denaturation indicator agent which is denatured due to temperature rise and which simulates an ultrasonic treatment effect, and egg white albumin as a denaturation sensitivity controlling agent which becomes a nucleus of cavitation when irradiation with an ultrasonic wave is carried out and which controls the temperature rise and the denaturation sensitivity of the indicator agent is prepared, and the properties thereof are evaluated. The evaluation results are described.
(1) Preparation of Phantom
[0033] All operations hereinafter were carried out at 4° C. An aqueous solution (86.5 ml) of containing 15% bovine serum albumin and 5 ml of pure water in which 0.1% egg white albumin had been dispersed and 25 ml of 40% solution of acrylamide (acrylamide:bisacrylamide=39:1) were sufficiently mixed with each other, followed by degasification. Then, the mixture was poured into a rectangular parallelepiped container. While the mixture was mildly stirred with a stirrer, 5 ml of 10% solution of ammonium persulfate and 5 ml of N,N,N′,N′-tetramethyl ethylenediamine were rapidly added. When they were mixed homogeneously, the stirring was stopped, a stirrer bar was removed, and a cover was put on the rectangular parallelepiped container and the container was stood still for 20 minutes. From the above-mentioned operations, substantially transparent gel was prepared and used as a tissue mimicking phantom. Furthermore, a gel which does not contain egg white albumin was prepared and used as a control phantom.
(2) Experimental System Used for Test
[0034] The below-mentioned tests were carried out by using an experimental system shown in FIG. 2 . An acrylic water tank 1 is filled with degassed water 2 , water temperature is kept at 37° C. or 25° C. by using a water temperature adjuster and a thermometer which are not shown in the drawing. In this water tank, the tissue mimicking phantom 3 or the control phantom prepared according to the above-mentioned phantom preparation method (1) were fixed to a focus position of convergent ultrasonic wave of the transducer 5 by the holder 4 in a state in which they were placed in a polyethylene bag having a thickness of 0.03 mm. The transducer 5 is connected to the waveform generator 6 and the signal amplifier 7 . Furthermore, in order to verify the position of the phantom 3 , the ultrasonic diagnostic device 8 and the diagnostic probe 9 are located in water. Furthermore, a camera 10 for observing an optical change of the phantom due to ultrasonic irradiation is disposed in a position at which a picture of the phantom 3 can be obtained. The waveform generating device 6 , the ultrasonic diagnostic device 8 , and the camera 10 are connected to the control oriented computer 11 and set such that a picture of the camera 10 is taken in synchronization with the ultrasonic irradiation from the waveform generating device 6 .
(3) Calculation of Denatured Region in Phantom
[0035] Calculation of a denatured region in a phantom in the below-mentioned tests was carried out by the following procedure.
[0000] (Cutting Out of Still Picture from Moving Picture)
Portions during ultrasonic irradiation were selected from moving pictures stored in the AVI format, then they were converted into a grayscale, and then cut out into a still picture group in the BMP format.
(Formation of Differential Image and Binarization)
[0000]
A differential image in which the brightness of the ultrasonic irradiation is subtracted from the brightness of each pixel of each still picture obtained in 1), and then, binarization processing in which pixels having finite difference of the brightness higher than the threshold obtained in the preliminary study are made to be white and pixels other than the above pixels are made to be black is carried out.
(Determination of Rotation Axis)
[0038] Pixel values of the pictures which had undergone binarization processing were multiplied in the direction of the ultrasonic irradiation, and a region showing the highest value was made to be a central axis in which denaturation occurred.
(Integration Processing)
[0039] Integration processing is carried out assuming rotational symmetry around the above-mentioned central axis. Note here that by applying the actual distance (unit: millimeter) in the image between the neighboring pixels which had been calculated, the results of the integration processing are made into a cubic millimeter unit.
Text Example 1
Effects when Ultrasonic Irradiation is Carried with Acoustic Intensity Varied
[0040] Firstly, a phantom was prepared according to the above-mentioned gel preparation method (1). An experimental system shown in FIG. 2 was used and a convergent ultrasonic wave transducer having a diameter of 48 mm and F value of 1.0 was brought into direct contact therewith in a state in which the temperature was kept at 37° C., and irradiation with an ultrasonic wave of 1.1 MHz was carried out for 15 seconds with the acoustic intensity varied from 0 to 1200 W/cm 2 . One example of the outline of the phantom after the irradiation with an ultrasonic wave is shown in FIG. 3 . FIG. 3 shows binarization by the above-mentioned processing method (3)-2). It is shown that the focal region of the ultrasonic wave becomes white in a form of a football. This is a denatured region. This denatured region is calculated in a cubic millimeter unit by the above-mentioned processing method (3), and the dependency on the ultrasonic intensity is obtained. One example of the result is shown in FIG. 4 . The drawing shows the result of a phantom into which egg white albumin as a denaturation sensitivity controlling agent was filled and the result of a control phantom which does not include a denaturation sensitivity controlling agent, together. According to FIG. 4 , the effect of the denaturation sensitivity controlling agent is remarkable. In the control phantom, the maximum intensity at which denaturation is not generated is 600 W/cm 2 , while in the case including a denaturation promoter, it is lowered to 200 W/cm 2 . Furthermore, when the ultrasonic irradiation is carried out in intensities not lower than the intensity necessary for the denaturation, in any intensities, the denatured region becomes larger when the denaturation sensitivity controlling agent is included. For example, in the intensity of 1200 W/cm 2 , about 3.5 times larger volume is denatured. Since the visual observation becomes easier and error in carrying out quantification becomes smaller as the volume is larger, the effect of the phantom into which a denaturation sensitivity controlling agent is filled is obvious as shown in FIG. 4 . Note here that the same experiment is carried out with the ultrasonic frequency varied from 1 to 6 MHz and the denaturation sensitivity controlling agent is allowed to co-exist similar to FIG. 4 , it is shown that the ultrasonic intensity necessary for denaturation can be lowered. It is also shown that as the ultrasonic intensity becomes higher, the denatured region tends to be increased. Furthermore, the same was true to the case in which milk albumin, blood globulin, and ultrasonic wave-denatured serum albumin were used as the denaturation sensitivity controlling agent. Note here that the denaturation sensitivity controlling agent shows an effect when the turbidity shown in FIG. 10 is 0.001 or more, but it is used in the concentration in which the turbidity is about 0.1 or less in order to secure the optical transparency of the phantom and the uniformity in the denaturation.
Text Example 2
Effects when Ultrasonic Irradiation is Carried with Acoustic Intensity Varied (Study at Room Temperature)
[0041] Study at room temperature assuming the use of phantom in a simple configuration without increasing temperatures was carried out. Firstly, phantom was prepared according to the above-mentioned gel preparation method (1). An experimental system shown in FIG. 2 was used and a convergent ultrasonic wave transducer having a diameter of 48 mm and F value of 1.0 was brought into direct contact therewith in a state in which the temperature was kept at 25° C., and irradiation with an ultrasonic wave of 1.1 MHz was carried out for 15 seconds with the acoustic intensity varied from 0 to 1200 W/cm 2 . This denatured region was calculated in a cubic millimeter unit by the above-mentioned processing method (3), and the dependency on the ultrasonic intensity was obtained. One example of the obtained result is shown in FIG. 5 . The drawing shows the result of a phantom into which egg white albumin as a denaturation sensitivity controlling agent was filled, the result of the control phantom which does not include a denaturation sensitivity controlling agent, and the result of the case in which an experiment is carried out by heating the control phantom which does not include a denaturation sensitivity controlling agent at 37° C., together.
[0042] According to FIG. 5 , the effect of the denaturation sensitivity controlling agent is remarkable also at room temperature (25° C.). Firstly, it is shown that the ultrasonic intensity necessary for denaturation is significantly lowered to 400 W/cm 2 from 800 W/cm 2 in the control phantom (25° C.). F Furthermore, when the ultrasonic irradiation is carried out in intensities not lower than the intensity necessary for the denaturation, in any intensities, the denatured region becomes larger when the denaturation sensitivity controlling agent is included. For example, in the intensity of 1200 W/cm 2 , the volume that is about 4.5 times larger than that of the control phantom (25° C.) which does not include the denaturation sensitivity controlling agent is denatured.
[0043] Since the visual observation becomes easier and error in carrying out quantification becomes smaller as the volume is larger, the effect of the phantom into which a denaturation sensitivity controlling agent is filled is obvious as shown in FIG. 5 . In particular, since this study is carried out at room temperature, it is not necessary to heat the water tank for verification, a verification system and a verification operation can be simplified. Note here that when the same experiments are carried out with the ultrasonic frequency varied from 1 to 6 MHz, and the denaturation sensitivity controlling agent is allowed to co-exist similar to FIG. 5 , it is shown that the ultrasonic intensity necessary for denaturation can be lowered. It is also shown that as the ultrasonic intensity becomes higher, the denatured region tends to be increased.
[0044] Furthermore, the same was true to the case in which milk albumin, blood globulin, and ultrasonic wave-denatured serum albumin were used as the denaturation sensitivity controlling agent. Note here that the denaturation sensitivity controlling agent shows an effect when the turbidity shown in FIG. 10 is 0.001 or more, but it is used in the concentration in which the turbidity is about 0.1 or less in order to secure the optical transparency of the phantom and the uniformity in the denaturation.
Text Example 3
Effects when Ultrasonic Irradiation is Carried Out with Indicator Agent Concentration Varied
[0045] In order to verify that the size of the denatured region can be controlled by varying the concentration of the indicator agent, phantom was prepared according to the above-mentioned phantom preparation method (1) with the concentration of the serum albumin varied. An experimental system shown in FIG. 2 was used and a convergent ultrasonic wave transducer having a diameter of 48 mm and F value of 1.0 was brought into direct contact therewith in a state in which the temperature was kept at 37° C. or 25° C., and irradiation with an ultrasonic wave of 1.1 MHz was carried out for 15 seconds with the acoustic intensity varied from 0 to 800 W/cm 2 . This denatured region was calculated in a cubic millimeter unit by the above-mentioned processing method (3), and the dependency on the concentration of albumin in the phantom was obtained. One example of the obtained result is shown in FIG. 6 .
[0046] According to FIG. 6 , it is shown that the effect of the denaturation promoter is changed dependent upon the concentration of albumin. At both 37° C. and 25° C., as the concentration of albumin is higher, the denatured region becomes larger. From this result, the phantom in accordance with the present invention can change the denatured region according to the property of the region to be simulated.
[0047] Note here that when the same experiment was carried out with the ultrasonic frequency varied from 1 to 6 MHz, similar to FIG. 6 , effects were demonstrated in which as the concentration of albumin was made to be higher, the size of the denatured region was increased. Furthermore, the same was true to the case in which blood globulin and ultrasonic wave-denatured serum albumin were used as the denaturation sensitivity controlling agent. Note here that the denaturation sensitivity controlling agent shows an effect when the turbidity shown in FIG. 10 is 0.001 or more, but it is used in the concentration in which the turbidity is about 0.1 or less in order to secure the optical transparency of the phantom and the uniformity in the denaturation.
[0048] From the above-mentioned tests, the effectiveness of the tissue mimicking phantom in accordance with the present invention is shown. Hereinafter, Examples in which it is actually used are described.
Example 1
[0049] An example of a phantom for evaluating ultrasonic-wave organism action is described. Hereinafter, one Example of the present invention is described with reference to FIGS. 7 and 8 . FIG. 7 shows an outer frame of the phantom. The phantom includes an outer frame main body 14 , an acoustic window 15 for ultrasonic irradiation, a window 16 for observing ultrasonic irradiation results, and an ultrasonic wave antireflection layer 17 . FIG. 8 is a view for showing one example of a phantom main body. The phantom main body includes three components of air bubble-mixed phantom 18 - 1 , liquid-mixed phantom 18 - 2 , and solid-mixed phantom 18 - 3 , which are prepared in a state in which they are brought into close contact with each other. When the phantom is used, the phantom main body prepared according to the preparation method (1) of phantom is filled into the inside of the outer frame shown in FIG. 8 .
[0050] At the use time as the phantom, an ultrasonic irradiation source to be evaluated is brought into close contact with the acoustic window 15 for ultrasonic irradiation and is irradiated with ultrasonic wave, and the result is observed from the window 16 for observing ultrasonic irradiation results. When the ultrasonic irradiation source and the acoustic window 15 for ultrasonic irradiation cannot be brought into contact with each other, irradiation with an ultrasonic wave can be carried out in a state in which the phantom and the ultrasonic irradiation source are placed into a water tank. Furthermore, irradiation can be carried out in a state in which a portion between the acoustic window 16 for ultrasonic irradiation and the ultrasonic irradiation source is filled with an acoustic coupling agent such as acoustic jelly.
[0051] Note here that in the preparation method (1), a homogeneous phantom is prepared, but the property of the phantom to be placed and used in the outer frame shown in FIG. 8 is not necessarily homogeneous. For example, as in the case as shown in FIG. 7 in which the outer frame is divided into a plurality of parts, and the air bubble-mixed phantom 18 - 1 , the liquid-mixed phantom 18 - 2 , and the solid-mixed phantom 18 - 3 are used in the parts respectively, different regions in the organism can be placed in the same frame of the phantom to be simulated. Furthermore, in the outer frame shown in FIG. 7 , other than the phantom, an absorbing body or a scattering body for preventing an ultrasonic wave with which the phantom is irradiated from returning to or being reflected from the irradiation source.
Example 2
[0052] An example of a calibration device of an ultrasonic treatment device is described. Hereinafter, one Example of the present invention is described with reference to FIG. 9 . The calibration device of the ultrasonic treatment device in this Example includes a phantom holding portion 19 , a temperature adjusting unit 20 , a temperature adjusting control unit 21 , a phantom photographing unit 22 , a device control unit 23 , and a treatment device interface section 24 .
[0053] The phantom holding portion 9 holds a phantom shown in FIG. 7 , and is configured to carry out irradiation with an ultrasonic wave. The temperature adjusting unit 20 is configured to control a temperature of the phantom placed in the phantom holding portion 19 in a temperature range from 20° C. to 40° C., and is controlled by the temperature adjusting control unit 21 . The phantom photographing unit 22 is configured to photograph a whole phantom, and the photographed results are transferred to the device control unit 23 . The device control unit 23 controls the temperature adjusting control unit 20 and the phantom photographing unit 22 , and is configured to hold phantom images photographed by the phantom photographing unit 22 and to carry out an image processing such as binarization, differentiation, overlapping, and the like. The treatment device interface section 24 is connected to a treatment device, and has functions of receiving the conditions for ultrasonic irradiation from the treatment device, transferring it to the device control unit 23 , and receiving the information on the phantom including, for example, the denatured region and the center position of denaturation of the phantom after ultrasonic irradiation from device control unit 23 transmits it to the treatment device.
[0054] Furthermore, when a parameter is input in advance, a function of setting information of whether or not the denatured region and the center position of the denaturation are included in the set range can be transferred to the treatment device, and a function of issuing an alarm when the obtained result is out of the set range or a function of disabling ultrasonic irradiation of the treatment device can be provided.
[0055] In carrying out the calibration device of this Example, for example, the following procedure is carried out. Firstly, in a treatment plan scheduled based on the a diagnostic image of an affected site to be treated, conditions such as an irradiation position of ultrasonic wave for treatment and irradiation time at each point are determined. In carrying out treatment, immediately before ultrasonic irradiation to the affected site, by using a calibration device including phantom according to forms and properties of the affected site of the present invention, ultrasonic irradiation is carried out in the same conditions in which treatment is carried out. When the denatured region is included in the assumed range, treatment is started. When the denatured region is not included in the assumed range, maintenance is carried out with respect to abnormality of the treatment device.
REFERENCE SIGNS LIST
[0000]
1 water tank
2 degassed water
3 tissue mimicking phantom
4 holder
5 convergent ultrasonic wave transducer
6 waveform generator
7 signal amplifier
8 ultrasonic diagnostic device
9 diagnostic probe
10 camera
11 control oriented computer
14 phantom outer frame main body
15 acoustic window for ultrasonic irradiation
16 window for observing ultrasonic irradiation result
17 ultrasonic wave antireflection layer
18 example of tissue mimicking phantom to be filled in outer frame
19 phantom holding portion
20 temperature adjusting unit
21 temperature adjusting control unit
22 phantom photographing unit
23 device control unit
24 treatment device interface section
100 hydrophone
101 sample for measuring cavitation generation
102 oscilloscope
|
A tissue mimicking phantom for ultrasonic treatment and a calibration device of an ultrasonic treatment device using the phantom are aimed to be provided. In order to dissolve the above-mentioned problems, the tissue mimicking phantom in accordance with the present invention is characterized by including an indicator agent which is denatured by an increase in temperature and which simulates an ultrasonic treatment effect, and a denaturation sensitivity controlling agent which is a different component from that of the indicator agent, which serves as a nucleus of cavitation at the time of ultrasonic irradiation, and which supports the increase in temperature and the denaturation of the indicator agent. The configuration makes it possible to obtain an tissue mimicking phantom which resolves the shortage of sensitivity, and which has excellent stability.
| 0
|
BACKGROUND OF INVENTION
(a)Field of the Invention
The present invention concerns a valve assembly for non-returnable packing or non-rechargeable container, of the type comprising a valve housing including a main valve forced into closing by means of a first return spring, and capable of cooperating with a means of operating the valve against the action of the spring. (b)Description of Prior Art
The increasingly frequent use of light packings which should only be filled once, so called non-returnable packings, raises safety problems with respect to their eventual reuse which is prohibited, especially since, in certain cases, the pressures use can be high.
To remove the possibility of some later filling by a user who is not aware of the law or of the dangers associated with such an operation, the invention proposes a new valve assembly whose structure is simple and compact, of low manufacturing cost, exclusively permitting the initial filling of the packing and preventing without any doubt any new filling subsequent to an at least partial emptying of the packing.
SUMMARY OF INVENTION
This object according to the invention is achieved by providing in the housing, an auxiliary valve which is in series with the main valve and is urged into closing by means of a second low calibration spring and is initially maintained in opening position through a locking means which is initially set in locking position and is displaceable into a definite unlocking position by the main valve when a pronounced opening is exerted on the main valve beyond its normal opening travel.
With this arrangement, after having proceeded, at the plant station, to the known filling of a packing with a liquid and/or gas, it is only necessary to produce a more pronounced displacement of the main valve to achieve the unlocking of the auxiliary valve which will adopt a closing position under the action of the second spring. It will be understood that a subsequent drawing off is quite possible, since the auxiliary valve opens under the action of the initial drawing off depression because of the internal pressure in the packing, but that on the contrary, it will remain in closed position if one tries to fill the packing, because of the effect of the second spring which is reinforced by the external pressure during a second attempt of refilling.
According to a more specific characteristic of the invention, the main and auxiliary valves are mounted coaxially with respect to the locking means which consists of a member with resilient lugs capable of enabling engagement between the auxiliary valve and the housing of the valve.
BRIEF DESCRIPTION OF DRAWINGS
Other characteristics and advantages of the invention will appear from the description which follows of embodiments given by way of examples, with reference to the annexed drawings, in which:
FIGS. 1 to 3 are cross-section views of a first embodiment of valve assembly in the following positions: FIG. 1, ready for loading; FIG. 2, during loading; FIG. 3: at the end of loading and during drawing off.
FIG. 4 is a perspective view of the locking member of FIGS. 1 to 3;
FIG. 5 is a view similar to FIG. 1, of a second embodiment;
FIGS. 6 to 8 are views similar to FIGS. 1 to 3, of a third embodiment;
FIG. 9 is a perspective view of the locking member of FIGS. 6 to 8.
DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIGS. 1 to 3, a fluid container under pressure of the non-returnable type comprises a bottle body 1 with a neck 2 having two consecutive inner annular shoulders 3 and 4. The deeper shoulder 4 serves to sealingly support a housing of a tubular valve 7, by means of a widened edge 6 and a seal 5, said housing being kept in position in the neck 2 by means of a plug 8 screwed at 9 in the neck 2, and having a central opening 10 allowing the passage of a tubular valve head 11 and a recess 12 for mounting a tap 13. The assembly is made undismantable and impervious by crimping (at 14) the end of the neck 2 on the plug 8 and/or by driving in, with punch blows 15, the wall of the neck 2 in a peripheral channel 16 of the plug 8.
Through its axial end wall 20, the valve housing 7 has an opening 21 enabling the passage of the valve head 11 with a seal 22 placed in between, said seal being positioned in wall 20 of housing 7. Valve head 11 constitutes an extension projecting outside valve housing 7 of a main valve, so called filling-tapping valve 25 made of a movable part, including, in addition to valve head 11, a main filling-tapping valve 26 provided with a seal 27 cooperatively acting as a closing support against wall 20 about opening 21, a valve body 28 and a stem 29. Valve head 11 presents an axial duct 30 outwardly opening at a free end which is provided with studs 31, and inwardly through radial ducts 32 located immediately above valve 26. A compression spring 33 is engaged around valve body 28 and is supported, between valve 36 and an inner shoulder 34, in the housing 7. This shoulder 34 is advantageously constituted of a bottom member 35 set in an envelope 36 of the valve housing 7. Bottom member 35 additionally has two consecutive shoulders 37 and 38 and a cylindral bearing 39 for the free guiding of an auxiliary valve 40, so called filling-prevention valve, formed of a movable part 41, having a holding head 42 for holding or resilient locking member 44 of the movable part 41, a valve 45 with lower seal 46 and a stem 47 projecting through a duct 48 to end in a holding ring 49 of a compression spring 50 with low calibration thrust against the external front face of the bottom member 35.
The resilient holding member 44 is formed of an annular body 51 from which extend three or four lugs in the form of blades 52 each terminating in a bent finger 53.
Initially, during manufacture, the lugs 52 are all engaged through the opening defined by the shoulder 34 until the bent fingers are resiliently locked above shoulder 34 which corresponds to the cocked position in locked opening of the auxiliary valve 45.
The valve housing 7 which has just been described, once mounted on a bottle 1 by means of the plug 8 is provided, at the filling station, with a filling tap 60 wherein the body 61 is screwed at 62 in an inner thread 63 of the plug 8 with a seal joint 64 in between. A tap rod 69 with operating button 690 is screwed at 68 in an axial duct 65 of the tap body 61 which outwardly communicates with a lateral duct 66 having a connection 67. The tap rod 69 has an axial projection which is sufficiently long to adopt the three consecutive positions referred to by the indications a (maximum exit position of rod 69), b (slight depression of rod 69) and c (maximum pressure of rod 69). In position a, the free end 69' of rod 69 is near to the end of the head 11 of the movable part 25 of the main valve 26, and valve 26 is therefore in sealing closure engagement, while the auxiliary valve 45 is kept in opening position by means of locking member 44.
A source of compressed gas is then hooked on connection 67 and tap rod 40 is operated until reaching depression mark b in which position the movable part 25 is slightly displaced so as to free the main valve 26 from its seat 20, without by doing this causing the stem 29 to abut against head 42 of the movable part of the auxiliary valve 45, which therefore remains in open locked position. Gas under pressure can then be introduced into the bottle through ducts 30, 32 and 48 (see FIG. 2).
At the end of the filling operation, the tap rod 69 is operated by means of button 690 so as to produce a maximum depression thereof (mark c), which causes the stem 29 of the main valve 26 to rest in thrust position against head 42 of the auxiliary valve 40 so as to induce a definite and non-resettable unlocking of the holding means 44 by forcing the lugs 53 out of engagement with shoulder 34. The auxiliary valve 45 is then immediately moved towards its closing position (FIG. 3) under the action of the spring 50, since the same pressure resides on both parts of this valve 45. The tap 60 is thereafter closed again by causing the rod 69 to climb again (FIG. 3).
After that, the source is disconnected and the tap 60 is removed by unscrewing. The packing is ready to be stored and/or shipped to the user.
At the location of use, a known tap is positioned, which however has only two positions opening and closing. Any opening thrust on the valve 26 produces a gaseous tapping and, as a result of the lowering of the pressure downstream of the auxiliary valve 45, there is an immediate opening of the valve 45 which thus frees some gas from the bottle.
At the end of the tapping operation, the auxiliary valve 45 stops rising and therefor remains in closing position on its seat 38 under the action of the compression spring 50.
In this embodiment, any attempt of refilling by the user is bound to end in failure. Even when using the special three-way tap 60 of the filling station, the auxiliary valve 55 remains permanently in closing position on its seat 38 and any arrival of gas can only reinforce this closing position. The packing is therefore undoubtedly non-reusable.
A variant of the embodiment of FIGS. 1 to 4 has been represented in FIG. 5.
The valve housing 7 is mounted here by simple screwing or setting at 71 inside a stamped collar 72 of a packing cover 1, after which the end of the collar is bent at 73 to enclose the valve housing 7. Tap 60 for the controlled opening of the main valve 26 and for unlocking the auxiliary valve 45 is mounted by screwing tap body 61 outside collar 72. The auxiliary valve 45 is here locked with a holding means 44 located outside the valve housing 7 and made unitary with part 50 of the auxiliary valve by being pinched between ring 49 and spring 50. The plugs 53 rest here on an outer collar 34' at the lower end of the housing 7. The stem 29 of the equipment of the main valve 26 is here bulkier and rests directly on the auxiliary valve 45.
With reference to FIGS. 6 to 8, a bottle 1 with a neck 2 is provided with a valve housing 7 having a body 74 screwed inside collar 2 until it rests tightly against an upper edge 75 on the portion 76 of the bottle neck 2 with a seal joint 75 in between, the entire assembly being made nondismountable by means of punch marks 15 on the neck opposite groove 16.
Body 74 has a central axial duct 78 with a central part 79 defining a recess for the equipment of the main body 25, an upper portion of enlarged diameter 80 with internal abutting shoulder 80' for a filling-tapping tap 600, and a lower widened part forming a recess 81 for the auxiliary valve 45, this recess 81 being closed by means of a screwed cap 82 having a throughgoing duct 83 on the lower side, preceded by a wide internal shoulder 84.
The main valve 25 has a valve body 85 screwed in an intermediate portion of the central duct 78 until abutting on an internal shoulder 86. This valve body 85 defines an axial duct with an internal abutting shoulder for a compression spring 87 resting on the other hand on a collar upstream of a valve rod 88 having an upper operating projection 89 and a lower stem 29 constituting an extension of the main valve 26, which incorporates an annular joint 27 to operatively engage with the lower seat forming the front end 90 of the valve body 85. The stem of the valve 29 is opposite the auxiliary valve 45 which is itself formed of an extension 91 forming a mounting stud for a compression spring 50', with low calibration, disposed between valves 26 and 45.
The annular joint 46 of the auxiliary valve 45 is adapted to sealingly rest against shoulder 84 to form a seat around the central duct 83 at the bottom of cap 82.
The auxiliary valve 45 has a peripheral groove 98 for the provisional holding of the auxiliary valve 45 in locked position when spaced from the seat 84, which is made possible by means of a flexible annular disk 99 comprising at least two, typically three lugs 99a and 99b radially directed towards the inside and engaged in groove 98 and whose outer periphery is sealingly pinched between an internal shoulder 100 of the cap 82 and the lower front edge of the body of housing 7.
As previously mentioned, the filling-tapping device 600 has a body 61 adapted to be screwed in recess 80, with a lower axial protuberance 610 and an axial duct 611 outwardly opening through radial ducts 612.
Before a first filling, body 61 is screwed to an intermittent position (FIG. 7) where the protuberance 610 has come to rest on the extension 89 of the main valve downwardly pushing the main valve rod 88 and freeing the main valve 26 from its seat 90.
In this intermediate position, the lower stem 29 of the main valve 26 is not yet in contact with the extension of the auxiliary valve 45 which is kept locked in opened position by means of the disk 99. Loading can then take place, the two main and auxiliary valves 26 and 45 being both in opened position. As soon as loading is over, a more extended screwing of body 61 (FIG. 8) is carried out, so that the stem 29 is in thrust contact with the extension 91 of the auxiliary valve 45. Beyond an axial position of a maximum deformation, the lugs of the holding disk 99 exit from the groove 98 and the auxiliary valve 45 is definitely unlocked, to rest against seat 84 under the effect of the spring 50', and allow transit through the duct 83 only in the direction of tapping of the content of packing 1.
|
The valve assembly for non-returnable packing comprises a valve housing including a main valve and an auxiliary valve the latter being initially kept in opened position through a resilient locking device which is unlocked, at the end of a first filling through a displacement of the main valve beyond its position of normal opening under the action of a long travel filling tap. The auxiliary valve is then forced to rest on its seat by means of a spring with low calibration. Any depression caused by tapping would provoke the opening of the auxiliary valve, while any overpressure resulting from filling would hit the auxiliary valve in a closed position.
| 8
|
BACKGROUND OF THE INVENTION
1. Firld of the Invention
The present invention relates to a planetary mixer for kneading materials to be processed, for instance, by means of blades which undergo a plantary motion.
2. Background Information
A planetary mixer of the sort known in the art is such that two blades undergo a planetary motion within a tank. In the case of such a conventional mixer with the two blades disposed symmetrically, loads acting on the respective blades differ from each other while materials are being processed in the tank, thus acting as a variable load on an agitating shaft. As a result, the load, adversely affects the operation in the form of vibration and the like. When highly viscous materials are processed, moreover, the materials may collect together columnarly, which may in turn prevent a sufficient shearing force from being inparted to the materials
When the two blades are caused to undergo planetary motion, a dead space may be produced between the blades in the central part of the tank, the dead space having on effect on giving the blade a motion. An insufficient shearing force is therefore provided for the materials.
Although there is a known planetary mixer whose agitating shaft is set eccentric from the center of its tank, a variable load also acts on the agitating shaft in this case, thus causing troubles.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a planetary mixer designed to make the blades do equal work simultaneously to suppress the generation of a variable load and which is capable of uniformly mixing and agitating materials without allowing them to columnarly collect together.
Another object of the present invention is to provide a planetary mixer capable of eliminating a dead space in a tank while the blades are moving and which is capable of dispersing and kneading materials efficiently by applying a shearing force to the materials between the blades and the inner wall of the tank and also between the blades in the central part of the tank.
The foregoing objects of the present invention can be accomplished by providing a planetary mixer, having three driven shafts secured to a rotary body fixed to a drive shaft, the driven shafts being disposed at equal intervals around the drive shaft, wherein the driven shafts are caused to undergo a plantary motion by means of a planetary gear, and wherein blades are provided at the trailing ends of the respective driven shafts in such a way that the blades rotate in close proximity to the inner wall of the tank.
Further, the objects of the present invention can be accomplished by providing a plantary mixer having three driven shafts which undergo plantary motion and which are disposed at equal intervals in the direction of their orbital motion, wherein the breadth of the blades fitted to the driven shafts is arranged so that the ends of the blades overlap each other, and wherein the ends thereof are formed so as to revolve in close proximity to the inner wall of the tank.
Still further, the objects of the present invention can be accomplished by providing a plantary mixer having a pillar-post provided at the center of the tank, and having three blades which undergo plantary motion in close promixity to the pillar-post.
These and other objects, features and advantages of the invention will become more apparent with reference to the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of a plantary mixer embodying the present invention, illustrating a cover and a tank in section.
FIG. 2 is an enlarged sectional view of the drive shaft portion of the planetary mixer shown in FIG. 1.
FIG. 3 is diagram illustrating the relation between the blades and the tank.
FIG. 4 is a diagram of another embodiment of blades embodying the present invention, illustrating the relation between the blades and the tank.
FIG. 5 is an elevational view of another planetary mixer embodying the present invention, illustrating a tank and a cover in section.
FIG. 6 is an enlarged sectional view of part of the drive shaft position of the planetary mixer shown in FIG. 5.
FIG. 7 is an elevational view of still another planetary mixer embodying the present invention, illustrating a tank and a cover in section.
FIG. 8 is a diagram illustrating the relation between the blades and the tank in the embodiments shown in FIGS. 5 and 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1 as an elevational view of a planetary mixer according to the present invention, a body 1 accommmodates a detachable tank 2 and an agitating head 3 disposed over the tank. The head 3 is guided by a guide rod 4 and vertically moved by a hydraulic cylinder 5. The head 3 may vertically be moved by two hydraulic cylinders provided in the form of a gate. The head 3 is also fitted with a motor 7 for rotating a drive shaft 6. The transmission mechanism between the motor and the drive shaft 6 may be arranged in various ways, an example of which is, as shown in FIG. 1, to use a chain 10 for connecting a drive sprocket 8 formed on the motor shaft with a driven sprocket 9 on the drive shaft 6.
As shown in FIG. 2, the drive shaft 6 extends through a support cylinder 11 fixed to the head 3, the upper and lower portions being rotatably supported by bearings 12, 13, respectively. A rotary body 14 is fixed with a key 15 at the trailing end of the drive shaft 6. The peripheral edge of the rotary body 14, which is cylindrical in configuration, is extended upward and screwed in a rotatable cover plate 16 that is put on the support cylinder 11. Three driven shafts 17, 17, 17 are rotatably carried by to the rotary body 14 in such a way as to surround the drive shaft 6. In terms of a plan as shown in FIG. 3, 17 the driven shafts 17 are disposed so that they are positioned at respective apexes of an imaginary equilateral triangle. The driven shafts 17 are rotatably supported by bearings 18, 19, respectively. A planetary gear 20 is fixed with a key 21 to the leading end of each driven shaft 17 and engaged with a ring shaped sun gear 22 supported by the support cylinder 11. Although an internal sun gear 22 secured to the support cylinder 11 in such a way as to surround the planetary gear is employed as the sun gear in FIG. 2, such a sun gear may be placed, if desired, in the center of the planetary gear in the leading portion of the support cylinder 11.
A blade 23 is fixed with a key 24 to the trailing end of each driven shaft 17 to make the blades 23 move in close proximity to the inner wall of the tank. The blades may be of the frame-type or of any other construction. The blades 23 shown in FIG. 1 are formed by 90-degree twisting of the lower side of a square frame piece, so that materials are forced down against the bottom of the tank 2.
The outer periphery of the rotary body 14 is enclosed with a cover 25.
When materials are put into the tank 2 with the head 3 lowered, each blade 23 rotates on the axis of the driven shaft 17 and simultaneously revolves around the drive shaft, i.e., the blades 23 undergo a planetary motion. With the use of the stationary internal sun gear 22 as shown in FIG. 2, the direction revolution of the blades 23 is rendered opposite to that of rotation of the blades 23. As the blades 23 conduct the planetary motion in close proximity to the inner wall of the tank 2, a strong shearing force is applied to the materials between the blades and the wall of the tank and between the blades. As a result, the materials can satisfactorily be dispersed, agitated, kneaded and the like. Since the three blades operate likewise, the three driven shafts bear an equal load and this makes it possible to use the mixer without the worry of causing a variable load. In addition, the materials are prevented from columnarly collecting together.
FIG. 4 illustrates another embodiment of the present invention. As shown in FIG. 4, the widthwise extent or breadth of the blades is arranged so that the ends of the blades overlap each other when the blades conduct the planetary motion. In other words, the breadth (the distance between the opposite radial ends of the blade is made longer than the distance between the axes (ab), (bc), (ac) of the driven shafts 17. Moreover, the radius (covering the length from the axis of the blades shaft up to the end edge thereof) of a blade 26 rotating in close proximity to the inner wall of the tank is set slightly shorter than the distance from the shaft position (a), (b), (c) up to the inner wall of the tank. While the end of one blade 26 is directed to the center as shown in FIG. 4, the ends of the remaining two blades 26, 26 are arranged at a position close to the intersection of their rotary loci, whereby these latter two blades are caused to overlap each other within the range of intersection of their rotary loci, when they are turned in the direction of the arrows.
In this arrangement, as the blades conduct the planetary motion in close proximity to the inner wall of the tank together with their end edges overlapped, a strong shearing force is applied to the materials between the blade and the inner wall of the tank and between the blades. As a result, the materials can satisfactorily be dispersed, agitated, kneaded and the like. Since the three blades overlappingly conduct a motion, moreover, a dead space is practically prevented from being produced in the tank. Therefore, the materials are efficiently processed and prevented from columnarly collecting together.
FIGS. 5 to 8 illustrate other embodiments of the present invention. These embodiments differ in construction from those described above by provision of a center pillar-post (27) formed in order for the blades to move in close proximity to a dead space which is liable to occur at the center of the tank when the blades undergo the planetary motion. Thus, the same portions are indicated with the same numerals. The thickness and the shape of the pillar-post 27 are determined to provide a sufficient shearing force for the materials between the blades in conformity with their size and configuration, the pillar-post being columnar, conical or the like. Although the pillar-post 27 shown in the drawings is a solid rod, it may be hollow so as to let a temperature-adjusting medium such as cooling water pass therethrough.
The pillar-post 27 shown in FIGS. 5 and 6 is secured to the bottom of the rotary body 14 and made to rotate together therewith. On the other hand, a pillar-post 28 shown in FIG. 7 is erected uprightly at the center of the tank 2 and remains unrotatable. When the blades are in operation, they undergo planetary motion in close proximity to the inner wall on the outer periphery of the tank and in close proximity to the pillar-post 27, on the inner periphery thereof. Consequently, the shearing force is applied to the materials to be processed in both the vicinities, whereby they are satisfactorily dispersed, agitated, kneaded and the like.
|
A planetary mixer having blades which conduct a planetary motion within a tank. A head vertically movably provided above the tank has a drive shaft extending downwardly. The drive shaft has a rotary body, which is provided with three driven shafts at positions corresponding to the respective apexes of an equilateral triangle. The blade is provided at the leading end of each driven shaft. When the rotary body is rotated by the drive shaft, a planetary gearing causes the three blades to rotate on the respective axes of the driven shafts and to simultaneously revolve them around the drive shaft, so that they conduct the planetary motion.
| 1
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a display device and a method for driving the same, and more particularly, to a display device and a method for driving the same that can uniformly maintain a degradation deviation of a whole display panel in upper, lower, left, and right directions in a self-luminescent display device.
[0003] 2. Background of the Related Art
[0004] Generally, a display device has a degradation deviation on a display panel by driving the display panel. Recently, self-luminescent display devices, such as a cathode ray tube (CRT), a field emission display (FED), a plasma display panel (PDP), and an electroluminescence (EL), are used as display devices. Since such self-luminescent display devices have a variable screen in view of a graphic screen, certain pixels of a panel are not continuously maintained in turn-on or turn-off state.
[0005] However, in a text screen, when the text screen is continuously displayed, some of pixels constituting the text screen can continuously be maintained in turn-on state while other pixels can continuously be maintained in turn-off state.
[0006] Therefore, a great difference exists between luminance of pixels continuously maintained in turn-on state and luminance of pixels continuously maintained in turn-off state. In other words, the pixels continuously maintained in turn-on state have a short life due to degradation while the pixels continuously maintained in turn-off state relatively have a long life.
[0007] The pixels having different lives deteriorate picture quality of the display device.
[0008] To solve such a problem, there is provided a method for prolonging a life of a display panel of a display device by applying an inverse voltage to the display panel. However, this method is made without any noticeable result.
[0009] FIG. 1 is a diagram showing a display of a general text type.
[0010] Luminance according to lives of pixels continuously maintained in turn-off state in FIG. 1 is shown in an upper graph of FIG. 2 . As shown in FIG. 2 , it is noted that luminance of pixels continuously maintained in turn-on state according to their operation time is remarkably deteriorated as compared with the pixels continuously maintained in turn-off state.
[0011] Meanwhile, the pixels continuously maintained in turn-off state have lower luminance than the pixels continuously maintained in turn-on state. Luminance of pixels continuously maintained in turn-off state according to their operation time is shown in a lower graph of FIG. 2 .
[0012] In other words, in the pixels continuously maintained in turn-on state, charges continuously move within them. Accordingly, as shown in the lower graph of FIG. 2 , the pixels continuously maintained in turn-on state have rapidly deteriorated luminance according to life as compared with the pixels continuously maintained in turn-off state. Further, the pixels continuously maintained in turn-on state have a shorter life than the pixels continuously maintained in turn-off state.
[0013] Consequently, the life difference generates luminance difference between the pixels and deteriorates picture quality of the display device.
[0014] In other words, if the display device displays a text screen, once the pixels are set up in turn-on or turn-off state, they continuously remain as they are. In this case, luminance difference exists between the turned on pixels and the turned off pixels, thereby remarkably deteriorating picture quality.
SUMMARY OF THE INVENTION
[0015] Accordingly, the present invention is directed to a display device and a method for driving the same that substantially obviates one or more problems due to limitations and disadvantages of the related art.
[0016] An object of the present invention is to provide a display device and a method for driving the same that can prevent picture quality from being deteriorated.
[0017] Another object of the present invention is to provide a display device and a method for driving the same that can minimize a degradation deviation between pixels continuously maintained in turn-on state and pixels continuously maintained in turn-off state.
[0018] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
[0019] To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a display device confirms whether display data applied to a display panel are uniformly maintained for a predetermined time. As a result of confirmation, if the display data are uniformly maintained for a predetermined time, pixels of the display panel are made for a predetermined block unit so that screen save modes are performed to sequentially apply screen save mode data to pixels of each block. The screen save modes are completed after there are sequentially performed for all blocks on the display panel.
[0020] Preferably, as a result of confirmation, if the display data are changed for a predetermined time, the display data are recognized as active data such as graphic data. Therefore, the display device directly displays the display data on the display panel without performing the screen save modes.
[0021] Preferably, to uniformly maintain picture quality of the display device, the screen save mode data having a predetermined type to be directly applied to the display panel if the display data are not changed for a predetermined time are in advance stored in a memory of the display device.
[0022] Preferably, to perform the screen save modes, the pixels can be made for one block unit among a block consisting of a plurality of pixel columns, a block consisting of plurality of pixel rows, and N×M (N, M is a positive integer) pixel block. At this time, screen save mode data designated as turn-on or turn-off are simultaneously applied to all pixels within the same block.
[0023] Preferably, to perform the screen save mode, the pixels are divided into one of the column block, the row block, and the N×M block, and an inverse value of the display data is periodically applied to the pixels within each block.
[0024] Preferably, as the screen save mode data, certain graphic data can be provided to the display panel at a certain time period to uniformly maintain the degradation state of the whole pixels.
[0025] It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
[0027] FIG. 1 is a diagram showing a display of a general text type;
[0028] FIG. 2 is a graph showing lives of pixels in the related art;
[0029] FIG. 3 is a block diagram showing a configuration of a display device according to the present invention;
[0030] FIGS. 4A and 4B are diagrams showing a screen save mode that turns on pixels for a column block unit;
[0031] FIGS. 5A and 5B are diagrams showing a screen save mode that turns on pixels for a row block unit;
[0032] FIGS. 6A and 6B are diagrams showing a screen save mode that turns on pixels for N×M block unit;
[0033] FIG. 7 is a graph showing lives of pixels according to the present invention;
[0034] FIGS. 8A and 8B are diagrams showing a screen save mode using inverse data; and
[0035] FIG. 9 is a flow chart showing a step of compensating degradation of a display device according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0036] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
[0037] Pixels of a display device may partially be degraded in view of characteristic of the display device. It is necessary to uniformly compensate display quality of whole pixels so as to uniformly maintain display quality of the partially degraded display device.
[0038] FIG. 3 is a block diagram showing a configuration of a display device according to the present invention.
[0039] Referring to FIG. 3 , the display device of the present invention includes a display panel 10 having a plurality of pixels arranged in a column and row unit, a pixel column driving unit 20 for driving the pixels in column, a pixel row driving unit 30 for driving the pixels in row, and a control unit 40 for driving the pixel column driving unit 20 and the pixel row driving unit 30 using a control signal.
[0040] The control unit 40 divides the pixels into a predetermined block unit by driving the pixel column driving unit 20 and the pixel row driving unit 30 using the control signal. The control unit 40 performs screen save modes of the display panel for the predetermined block unit.
[0041] Meanwhile, a reference numeral 50 which is not described denotes a memory that stores various types of the screen save modes.
[0042] The predetermined block for the screen save modes may be one of a column block consisting of at least one pixel column, a row block consisting of at least one pixel row, and N×M pixel block consisting of N×M (N, M is positive integer number) pixels.
[0043] The screen save modes may turn on or off all pixels within each block.
[0044] In FIG. 3 , the control unit 40 confirms whether display data applied to the display panel 10 are uniformly maintained for a predetermined time. If the display data are uniformly maintained for a predetermined time, the control unit 40 divides the display panel 10 into at least one block. The screen save modes are then performed. In other words, the display data and the screen save mode data are sequentially applied from the memory 50 to the one block of the display panel 10 under the control of the control unit 40 .
[0045] Meanwhile, if the display data are changed to other data during the screen save modes, the control unit 40 releases the screen save modes and displays the display data only on the display panel 10 .
[0046] If the display data are continuously variable data without being uniformly maintained for a predetermined time, the control unit 40 continuously displays the display data on the display panel 10 without performing the screen save modes.
[0047] Inverse data of the display data may be used as the screen save mode data.
First Embodiment
[0048] FIGS. 4A and 4B are diagrams showing screen save modes that turn on pixels of a display device for a column block unit.
[0049] In FIGS. 4A and 4B , a plurality of columns are regarded as one block unit and pixels are turned on for a block unit, so that the screen save modes are performed.
[0050] FIG. 4A shows a first column block 100 a of the screen save modes implemented for the column block unit, and FIG. 4B shows the last column block 100 d of the screen save modes implemented for the column block unit.
[0051] As shown in FIGS. 4A and 4B , the screen save mode is sequentially applied to each of the column blocks 100 a - 100 d, and the corresponding columns within the currently chosen column block ( 100 a in FIG. 4A and 100 d in FIG. 4B ) are turned on while columns corresponding to the other column blocks ( 100 b and 100 c ) are turned off, except for pixels that are displaying display data. These steps are repeated until the screen save modes of all column blocks 100 a - 100 d are completed.
[0052] The control unit 40 confirms whether the display data applied to the display panel 10 are uniformly maintained for a predetermined time. If the display data are uniformly maintained for a predetermined time, the control unit 40 divides the pixels of the display panel 10 into at least one pixel column block 100 a - 100 d. Then, the screen save modes are sequentially performed on the pixel column blocks 100 a - 100 d.
[0053] The screen save modes mean that pixels corresponding to each pixel column block are simultaneously driven in the same type. When the screen save modes are performed, the same type may be made in such a manner that all pixels within each block are turned on or off.
[0054] Meanwhile, if the display data are changed during the screen save modes, the control unit 40 releases the screen save modes and displays the display data only on the display panel 10 .
Second Embodiment
[0055] FIGS. 5A and 5B are diagrams showing screen save modes that turn on pixels for a row block unit.
[0056] In FIGS. 5A and 5B , a plurality of rows are regarded as one block unit and pixels are turned on for a block unit, so that the screen save modes are performed.
[0057] FIG. 5A show a first row block 200 a of the screen save modes implemented for the row block unit, and FIG. 5B shows the last row block 200 d of the screen save modes implemented for the row block unit.
[0058] As shown in FIGS. 5A and 5B , the screen save mode is sequentially applied to each of the row blocks 200 a - 200 d , and the corresponding columns within the currently chosen row block ( 200 a , FIG. 5A and 200 d in FIG. 5B ) are turned on while rows corresponding to the other row blocks ( 200 b and 200 c ) are turned off, except for pixels that are displaying display data. These steps are repeated until the screen save modes of all row blocks 200 a - 200 d are completed.
[0059] The control unit 40 confirms whether the display data applied to the display panel 10 are uniformly maintained for a predetermined time. If the display data are uniformly maintained for a predetermined time, the control unit 40 divides the pixels of the display panel 10 into at least one pixel row block 200 a - 200 d . Then, the screen save modes are sequentially performed on the pixel row blocks 200 a - 200 d by the control unit 40 .
[0060] The screen save modes mean that pixels corresponding to each pixel row block are simultaneously driven in the same type.
[0061] Meanwhile, if the display data are changed during the screen save modes, the control unit 40 releases the screen save modes and displays the display data only on the display panel 10 .
[0062] The screen save modes for the row block unit are useful for display devices that perform display for a character unit. In this case, a user can manipulate the display device for the screen save mode for the row block unit without reducing viewing sensitivity when viewing a screen displayed in the display device.
Third Embodiment
[0063] FIGS. 6A and 6B are diagrams showing screen save modes that turn on pixels for N 1 ×M 1 block unit.
[0064] FIG. 6A show a first N 1 ×M 1 pixel block 300 a of the screen save modes implemented for a certain pixel block unit, and FIG. 6B shows the last N 1 ×M 1 pixel block 300 h of the screen save modes implemented for the certain pixel block unit.
[0065] Pixels of the currently chosen N 1 ×M 1 pixel block ( 300 a in FIG. 5A and 300 h in FIG. 6B ) are turned on while pixels of the other N×M pixel blocks 300 b - 300 g are turned off, except for pixels that are displaying display data. These steps are repeated until the screen save modes of all N 1 ×M 1 pixel blocks 300 a - 300 h are completed.
[0066] The control unit 40 confirms whether the display data applied to the display panel 10 are uniformly maintained for a predetermined time. If the display data are uniformly maintained for a predetermined time, the control unit 40 divides the pixels of the display panel 10 into at least one N 1 ×M 1 (N 1 and M 1 are positive integers) pixel row block 300 a - 300 h. The screen save mode is then sequentially performed on the N 1 ×M 1 pixelblocks 300 a - 300 h.
[0067] At this time, the screen save modes mean that pixels corresponding to each N 1 ×M 1 pixel block are simultaneously driven in the same type.
[0068] Meanwhile, if the display data are changed during the screen save modes, the control unit 40 releases the screen save mode and displays the display data only on the display panel 10 .
[0069] When the screen save modes are performed, the same type may be made in such a manner that all pixels within each block are turned on or off.
[0070] FIG. 7 is a graph showing lives of pixels according to the present invention.
[0071] In FIG. 7 , a graph at an upper portion shows lives of the pixels of the display device when the screen save modes are performed on the display device for the pixel block unit while a graph at a lower portion shows lives of pixels when the pixels of the display device are continuously turned on without performing the screen save modes.
[0072] As shown in FIG. 7 , in the screen save modes of the present invention, it is noted that luminance difference according to a life reduced by half between the pixels continuously maintained in turn-on state and the pixels continuously maintained in turn-off state is not great. Accordingly, it is noted that picture quality of the display device can be improved.
[0073] FIG. 8A is a diagram showing a screen when the display device is in a general display state while FIG. 8B is a diagram showing a screen when turned on pixels and turned off pixels are inversed on the screen.
[0074] FIGS. 8A and 8B , the control unit 40 confirms whether the display data applied to the display panel 10 are uniformly maintained for a predetermined time. If the display data are uniformly maintained for a predetermined time, the control unit 40 divides the pixels of the display panel 10 into at least one pixel block 400 . Then, the control unit 40 sequentially applies the screen save mode data to the at least one pixel block 400 .
[0075] The screen save mode data are inverse data of data corresponding to each pixel block of the display data.
[0076] Meanwhile, the block for the screen save modes may be one of a column block consisting of at least one pixel column, a row block consisting of at least one pixel row, and a pixel block consisting of N×M(N and M are positive integers) pixels.
[0077] The screen save mode data are to turn off the pixels turned on according to the display data among the pixels belonging to each pixel block and at the same time to turn on the pixels turned off according to the display data among the pixels belonging to each pixel block.
[0078] As described above, when the pixel data of the current screen and their inverse data are provided to the screen of the display device, graphs on lives of the pixels of the display device are equal to the graph at the upper portion of FIG. 7 . Accordingly, the display panel of the display device has improved picture quality.
[0079] FIG. 9 is a flow chart showing steps of compensating degradation deviation of the display device according to the present invention.
[0080] If data are displayed on the display panel of the display device (S 1 ), the control unit 40 of the display device confirms whether the display data are uniformly maintained for a predetermined time (T sec.) without any change (S 2 ). If the display data are continuously changed, the display device continuously performs the display step under the control of the control unit 40 . Meanwhile, if it is determined that the display data are continuously displayed on the screen for a predetermined time, the display device is subject to the screen save modes according to the present invention under the control of the control unit 40 .
[0081] The screen save modes may be implemented in various types. These various types are previously divided and then stored in the memory of the display device. Also, the types of the screen save modes are previously designated by a user or manufacturer. The display device performs the screen save modes of the previously designated types as above. As an example, the first screen save mode is implemented for a column block unit, the second screen save mode is implemented for a row block unit, and the third screen save mode is implemented for a pixel block unit (S 4 ).
[0082] Meanwhile, it is confirmed whether the display data are changed during the screen save modes (S 5 ). If the display data are changed, the screen save modes are directly ended by the control unit 40 and the display device displays the display data on the screen (S 6 ).
[0083] As aforementioned, the driving method of the display device according to the present invention has the following advantages.
[0084] First, turn-on state and turn-off state of a plurality of the pixels to which the same data are successively applied for a predetermined time are switched so that the pixels can uniformly be turned on over the whole screen.
[0085] Furthermore, by periodically applying inverse data of current video data to the whole pixels constituting the screen, luminance deviation can uniformly be maintained at a small range between the pixels over the whole screen of the display panel. As a result, it is possible to improve picture quality of the screen.
[0086] The forgoing embodiments are merely exemplary and are not to be construed as limiting the present invention. The present teachings can be readily applied to other types of apparatuses. The description of the present invention is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art.
|
A display device and a method for driving the same are disclosed. The display device confirms whether display data applied to a display panel are uniformly maintained for a predetermined time. As a result of confirmation, if the display data are uniformly maintained for a predetermined time, pixels of the display panel are made for a predetermined block unit so that screen save modes are performed to sequentially apply screen save mode data to pixels of each block. The screen save modes are completed after there are sequentially performed for all blocks on the display panel. Thus, uniform luminance deviation can be obtained on the display panel of the display device and further picture quality of the display device can be improved.
| 6
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This patent application claims the benefit of U.S. Provisional Application Ser. No. 60/700,454, filed Jul. 19, 2005.
FIELD OF THE INVENTION
[0002] The present invention is directed to methods for reducing or eliminating the amount of condensation in a container. The methods comprise providing a container comprising a lid, wherein the amount of condensation in the container is reduced by: increasing the thickness of the lid; insulating the lid; or combinations thereof. The present invention is also directed to containers comprising a lid that provide a reduction in the amount of condensation resulting from temperature fluctuation, wherein the amount of condensation in the container is reduced by: increasing the thickness of the lid; shortening the walls of the lid; insulating the lid; or combinations thereof.
BACKGROUND
[0003] Condensation on the inside lid of containers, including Petri dishes and culture vessels, is a universal problem in the laboratory. Condensation problems result when the temperature of the inner surface of the lid of a container falls below the temperature inside the container itself. Condensation can take the form of either a light fog or large liquid droplets. When large liquid droplets form, they can drop from the lid onto the contents of the container, displacing the contents and creating liquid soaked microenvironments. When a light condensation is formed, the contents of the container are often obscured, which makes critical observations difficult and photodocumentation of the contents of the container very frustrating to achieve.
[0004] Condensation forms on the lids and sides of containers whenever a temperature differential occurs; such as, for example, if the temperature of the container lid is below the temperature of the contents of the container. This occurs most often when the temperature in a room fluctuates and falls, even by as little as 0.1° C. If a room cools, the container will retain some heat while the air temperature within the room and surrounding the container is lowered. Moisture or condensation will form on the relatively cool inner lid surface in the high humidity conditions that exist within the container.
[0005] The temperature of the inside of a container can also be increased and condensation results if the contents absorb sufficient light to generate heat energy. Placement of containers directly on dark surfaces in the light can give similar results, as the dark surface absorbs light energy, warming the container. In addition, bottom heat, generated from lights or equipment under shelves holding containers, can also lead to a temperature differential and condensation.
[0006] Even though many laboratories have very good temperature control, small fluctuations in temperature occur and, every time this happens, additional condensation forms. The end results can be layers of condensation, eventually forming water droplets on the lids of the containers. Some laboratories blow heated air over the tops of the containers or force cool air underneath the containers, which effectively keeps the lid temperature above the container temperature, eliminating condensation problems. However, most laboratories do not have these types of facilities.
SUMMARY OF THE INVENTION
[0007] The present invention provides methods for reducing the amount of condensation in a container comprising providing a container including a lid. The amount of condensation in the container is reduced by: increasing the thickness of the lid; insulating the lid, for example with a piece of insulating material; or combinations thereof.
[0008] The present invention also provides containers including a lid that provides a reduction in the amount of condensation resulting from temperature fluctuation. The amount of condensation in the container is reduced by: increasing the thickness of the lid; shortening the walls of the lid; insulating the lid with a piece of insulating material or combinations thereof. In one embodiment, the container is a culture container. In another embodiment, the container is a Petri dish. In yet another embodiment, the container is a culture dish. In a further embodiment, the container is a vented dish.
DETAILED DESCRIPTION OF THE FIGURES
[0009] FIG. 1 . A Petri dish with a thickened lid design.
[0010] FIG. 2 . A polymer disc is placed on top of a standard Petri dish lid (left) or in place of standard Petri dish lid (right); and
[0011] FIG. 3 . A composite image of Double Petri dish lids, consisting of a control and 4 different polymers, of 4 different thicknesses, taken over a 16 minute period. Condensation in this short-term experiment was subtle but is clearly observable. PG=Plexiglas, PS=polystyrene, PC=polycarbonate, PETC=an additional form of polycarbonate.
[0012] FIG. 4 . Petri dishes displaying condensation on the dishes' side.
DETAILED DESCRIPTION OF THE INVENTION
[0013] The inventor has discovered a way to reduce or eliminate condensation from forming on the surface of containers, such as Petri dishes and culture containers. By replacing the standard lid with other types of transparent materials in varying thicknesses, temperature differentials can be buffered; offering protection from fluctuations in temperature such that condensation does not form on the lid surface. The thicker materials insulate the lid from temperature fluctuations. If the temperature of the inside lid of the container is not reduced, condensation will not form
[0014] Various materials possess different thermal conductivities. Materials with high thermal conductivities allow heat to transfer quickly while materials with low thermal conductivities act as heat insulators. Most metals and glass have high thermal conductivities. Many plastics have low thermal conductivities and are good insulators. Petri dishes, for example, were originally manufactured from glass but are now manufactured primarily from polystyrene, which has a relatively low thermal conductivity. If the lids of Petri dishes (top part only), or all or a portion of the surface of other culture containers were manufactured with increased thickness or modified to include a pocket of insulating air, condensation problems could be reduced or eliminated. In addition, placement of a small piece of insulating material inside or on top of a Petri dish lid (outside of the container) yields similar results.
[0015] The invention does not require large changes in manufacturing basics. Containers can still be manufactured from polystyrene, which is optically clear, inexpensive and a good insulator (low thermal conductivity). The containers can still be made using molds and the bottom of the containers, for example the bottom of Petri dishes, can be produced exactly the same as they are now. The main difference is the top portion of the lid of a Petri dish or the top of another culture container. The new lid will be thicker on all or a portion of the top surface than they are in the prior art. The sides of the lid can remain the same thickness or the sidewalls of the lid may be shortened. While not wishing to be bound by theory, it is believed that if the sidewalls are shortened, the sidewalls will cool more quickly and, if any condensation does form, it will occur there. Condensation occurs at the thinnest point of the container, where insulation is minimal and the lid walls do not provide a second layer of insulating polymer material (See FIG. 4 , left—condensation is below the lid sidewall, on the bottom sidewall). Condensation on the side of the container is preferred as it will not obscure the container's contents from view and drops of condensation will be reabsorbed into the medium if they fall down the container side. However, as long as all or a portion of the top of the container is thicker, any water droplets, if formed, will slide down the sidewalls and be reabsorbed by the medium.
[0016] Alternatively to basic changes in Petri dish or culture container design, insulating materials can be placed either on top of the lid of the container or on the inside top of the lid of the container. Placement of insulating materials on the inside top of the lid of the container has the advantage that an additional pocket of air can be sandwiched in between the two surfaces, providing more insulation from temperature fluctuations.
EXAMPLES
[0017] The inventor initially evaluated discs of different clear plastic polymers and glass. There are a few different sizes of Petri dishes. The most common Petri dish size is 100×15 mm. For most of the experiments, the inventor used a 100×25 mm size. For the smaller dishes, it may be even more important to reduce the side walls of the lid, as the dish is so short.
[0018] The discs were cut to the same size as the Petri dish lid and were either sterilized and used in place of lids or placed on top of manufactured lids. Under conditions of temperature differential, moisture or condensation forms on the relatively cool inner lid surface.
[0019] To quantify condensation of the different lids, Petri dishes with modified lids were initially maintained in a laboratory where the temperature was maintained at 25° C. and transferred to conditions where the temperature could be gradually lowered. At specific time points, images of the Petri dishes were collected using a digital camera, mounted on a copy stand. Images were collected one dish at a time and as quickly as possible. The time of image collection was recorded. Condensation was quantified using Adobe Photoshop® by selecting a 1000×1000 pixel region of the image and reading the Mean value of intensity in the Histogram palette. The initial time point value was subtracted from the timed values, to yield a value for increase in condensation over time.
[0020] The four different polymers tested were Plexiglas, Polycarbonate, Polystyrene, and PETG, which is a form of Polycarbonate. Glass (borosilicate) was also initially evaluated, but its insulating properties were very poor and condensation comparisons of the glass to the polymers were difficult due to the different forms of condensation. The thermal conductivity of the four different polymers is slightly different. Those values are shown in Table 1.
TABLE 1 Thermal Conductivity Values Polymer Thermal Conductivity* PG - Plexiglas 1.32-1.67 PC - Polycarbonate 1.32-1.46 PS - Polystyrene 0.83-1.34 PETG - form of PC 1.32 Glass (borosilicate) 7.63 *for thermal conductivity values, lower values indicate low heat transfer and good insulation capacity. Thermal conductivity values were obtained from MatWeb.com Units: BTUs lost - in/hr/ft 2 with a 1° F. temp differential
[0021] Polystyrene has the lowest thermal conductivity, indicating that it is the best insulator. Polystyrene is also the standard material used in the manufacture of Petri dishes.
[0022] While conducting the short term experiments, the inventor encountered some problems. These problems included contamination of the plates, scratching the lids, oil from hands on the lids, uneven cooling, the camera focusing on its reflection, and dust on the dish lids.
[0023] The polymer lids were initially used in place of the standard manufactured lids. They needed to be cleaned for visual clarity and then sterilized (with ethanol) as the Petri dishes contained a standard culture medium, which would support the growth of bacterial and fungal contaminants if left untreated. Cleaning and sterilizing the dish lids using 70% or 95% ethanol was not successful. Latex gloves were used when handling alcohol-saturated wipes but microabrasion occurred from wiping the polymers with Kimwipes or paper towels. This scratching interfered with the image analysis and appeared to for a nucleus for condensation. The solution to this problem was to use the original dish lid as an inner lid then place the lid being tested on top of the original dish lid ( FIG. 2 ). This eliminated streaking and scratching. The original Petri dish lid inner surface provided a consistent surface for studies on condensation.
[0024] Experiments were set up by placing a set of Petri dishes with the modified lids in the laboratory, next to a window (in cool weather) and allowing the Petri dishes to slowly cool for 20 minutes. Temperature changes were monitored with a digital thermometer and temperature changes over the 20 minute experiments were 1.6-3.5° C. This temperature change is higher than would normally be encountered in a laboratory environment but the condensation response was more easily documented under these conditions.
[0025] A digital camera was used in a full manual mode to prevent the camera from focusing on its reflection instead of the Petri dish lid. In addition, a hood, consisting of a black sheet of fabric placed in front of the camera (with a hole cut for the camera lens), effectively eliminated background lighting and the remaining reflection problems. A piece of black velvet fabric was placed under the dishes for a high contrast background and the camera was mounted on a copy stand, which used 4×50 W bulbs for consistent illumination.
[0026] Dust, which could interfere with image analysis, was eliminated from the surface of the dish lids by wiping off the lids with a black felt glove between each image collection.
[0027] The values presented in Table 2 are taken from images that were analyzed separately but are presented collectively (as a smaller sample) in FIG. 3 . Table 2 values represent the changes in gray value intensity measurements from time 0. The experiment was repeated 5 times. Although the condensation shown in the composite image ( FIG. 3 ) appears at first to be subtle, it is easily quantifiable from the original image and gray value determinations are clear. Condensation of moisture on the lids of all of the Petri dishes increased over time as the temperature surrounding the Petri dishes decreased. The control dish lid, without the additional polymer disc, displayed the highest level of condensation while the thicker dish lids displayed the lowest increase. The polycarbonate lids, did not provide as much protection from condensation as the other polymers. Polystyrene, the component polymer of Petri dishes, appears to provide adequate protection from condensation, with the thickened lid.
TABLE 2 Double Lid - Condensation (mean gray value intensity) using different Petri dish lids Lid Thickness (mm) Range of Times for Image Collection - minutes and Type of polymer 4-6:30 7-13:00 12-16:30 15:45-20 Control 23.32 35.19 41.71 47.46 1.0 Plexiglas 12.68 23.20 29.35 35.78 2.0 Plexiglas 6.97 13.21 17.04 24.11 2.0 PETG 13.61 21.79 28.59 34.50 2.5 Plexiglas 4.57 12.99 19.11 23.13 3.5 Polystyrene 5.08 9.94 13.61 15.95 4.0 Polycarbonate 9.28 15.05 20.99 26.34 4.5 Plexiglas 0.98 2.75 7.87 10.60 5.5 Plexiglas 0.58 2.38 7.49 11.48 5.5 Polycarbonate 1.72 2.94 8.64 12.67 6.0 PETG 0.62 1.78 2.66 4.71
|
The present invention provides methods for reducing the amount of condensation in a container by providing a container comprising a lid, wherein the amount of condensation in the container is reduced by: increasing all or a portion of the thickness of the lid; insulating the lid; or combinations thereof. The present invention also provides containers comprising lids that provide a reduction in the amount of condensation resulting from temperature fluctuation.
| 2
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a mobile radio system comprising at least a first base station, at least a further base station and at least a switching centre.
The invention further relates to a base station, switching equipment and a detection and control arrangement for such a mobile radio system.
2. Discussion of the Related Art
In a mobile radio system there are provided a plurality of base stations for maintaining radio links to mobile subscriber units. A switching centre also referenced switching system in the following is used for establishing connections to the base stations allocated to the switching system. For a handover, the switching system comprises, for example, means which hand over, as required, a connection between the switching system and a mobile subscriber station existing via a first base station (call handover base station) to a second base station (call take-over base station).
Modem mobile radio systems currently comprise many individual radio cells which have each a limited coverage area. Each cell is supplied with radio signals by a base station, while the transmitter power of the base stations and of the mobile subscriber stations is adapted to the size of a radio cell. In this manner the same radio parameters (for example, frequencies, time slots or codecs) can be used in radio cells which are a specific distance apart, without having to take mutual interference into account.
While a base station is connected to mobile subscriber stations that are located inside its cell via a radio channel, the base stations themselves are connected to switching systems, for example, via cable transmission paths. The switching systems on their part are again connected to at least one fixed network, for example, the public telephone network (PSTN=Public Switched Telephone Network, or ISDN=Integrated Services Digital Network). Via the switching systems a mobile subscriber station can be linked to an arbitrary subscriber of the respective network (mobile originating call), or a subscriber of the respective network to an arbitrary subscriber of the mobile radio network (mobile terminating call). In the case of such a link, this may conventionally relate to a call link, but also to a data link, for example, for a facsimile transmission.
The moment a mobile subscriber station leaves the coverage area of a radio cell assigned thereto, there should be provided that the radio link to the mobile subscriber station is taken over by another radio cell i.e. by another base station. The occurrence of such a change of radio cells may be detected, for example, by measuring the signal field strength, the signal-to-noise ratio, the error probability, the distance between base station and mobile subscriber unit and so on. If such a situation is detected, both the radio link is to be handed over from one base station to the take-over base station and the transmission path between a network subscriber and the handover base station is to be switched to the take-over base station.
In a call handover method which is implemented, for example, in a GSM system, first a free radio channel is to be selected by the take-over base station. This channel is announced to the mobile subscriber station, so that the mobile subscriber station can maintain the radio link along the channel announced thereto. In other systems, for example, in DECT (Digital European Cordless Telecommunication), the selection of the new radio channel is made by the mobile station.
When the mobile station is changed to the new radio channel, also the link in the cabled part of the mobile radio system is to be switched over by appropriately driving the switching systems concerned. Then there is the problem that the radio channel and the switching systems are to be switched over substantially simultaneously, so that no perceivable pauses, for example, caused by clicking sounds, or even longer pauses, occur.
For this purpose, there has also been proposed to build up a conferencing circuit of the mobile subscriber with himself, that is, on the one hand, via the base station that hands over the call and, on the other hand, via the base station that takes over the call, so that there is always a link to the mobile subscriber, irrespective of the instant of switching. The cost of such conferencing circuits, however, is considerable. Furthermore, there is the problem that before the radio channel is switched over, the base station taking over the call, or after the radio channel has been switched over, the base station handing over the call, inserts a noise signal into the radio link that does not yet exist or no longer exists. This is tolerable, it is true, for call links, but, in the case of data links, this may lead to errors that can no longer be corrected.
EP 0 544 457 has disclosed a method for handling a call handover from a first base station to a second base station, in which the link from fixed-network subscriber to switching system is first led via a switch specially provided for the call handover before the radio channels are switched over. In preparation of the call handover, this switch completely establishes the connection path to the call take-over base station via the switching system to which the take-over base station is connected, including rendering the new radio channel available to the take-over base station. After this connection has been established, the handover base station announces to the mobile subscriber station that it is to change to the radio channel of the handover base station. Simultaneously, the switch is given the instruction to switch to the new connection already prepared. Subsequently, the previous connection to the take-over base station can be broken off via the switch.
In a special embodiment in which the (call) data are available as compressed time slot signals, the switch is arranged as a unit for time slot exchange. The advantage of the switch lies in the fact that, prior to the actual call handover, all connections are already prepared, and thus for a switch-over to the network only the time slot signals need to be switched over i.e. exchanged. Once an appropriate control signal has arrived at this switch, the switching may be effected without delay. In this manner the period of time in which the connection to and from the mobile subscriber station is dead is to be smaller than 150 ms.
This switching time may be acceptable for call links. For data transmission, however, a switching time of this order of magnitude is no longer acceptable.
SUMMARY OF THE INVENTION
It is an object of the invention to keep the dead time caused by a call handover shortest possible.
This object is achieved in that the first and the further base station include switching equipment for inserting a signal coming from the switching centre into the signal going to the switching centre.
The invention is based on the recognition that rather not the switching times in the individual components of the mobile radio system are problematic for a call handover, but longer dead times, caused by the fact that between recognizing the necessity of operating the switching system (=switching centre) and the execution, switch commands are to be transmitted with a finite delay. As not all of the switch commands arriving at a switching system can be executed forthwith, but, for example, are to be put in a queue, the length of this delay time also depends on other factors, for example, on the traffic load of the switching system. The delay time may thus vary considerably and even be longer than 150 ms under circumstances. In principle, it is of no importance to the function of the invention at which position between switching system and mobile subscriber station the switching equipment (switching means) is arranged. It is even possible to position the switching means in the switching system, as long as the requirement is fulfilled that the switching means are switched at a defined switching instant when a call is handed over. An advantageous embodiment of the invention provides, however, that the means for inserting a signal coming from the fixed network into the signal going to the fixed network are accommodated in the base station. In a further embodiment the means for detecting a call handover, which means control the coupling means, are also accommodated in the base station. In this manner the necessary modifications of an existing mobile radio system may be kept smallest possible.
The switching equipment (switching means) proposed by the invention may be arranged such that when the radio channel is switched over to, the switching operations take place substantially without delay. The invention is based on the idea of allowing real-time switching operations to be carried out autonomously by the switching means located in the line handing over the call and in the line taking over the call. In this manner the switching operation is subdivided into various sub-phases during a call handover, while real-time sub-phases are handled by the switching means, but the switching system is switched over in non-real-time sub-phases.
For embodying the invention it is a matter of the switching means being activated substantially simultaneously with a call handover i.e. with the actual change of radio channels. Therefore, it is advantageous to provide separate means for detecting the call handover, so as to influence the switching means directly i.e. without any time delay. Preferably, switching means and detecting means can be installed together, so that for the switching signal from the detector to the switching means no additional signalling need to be sent along a transmission path.
The control of a call handover may be ensured in that the switching equipment comprises a detection and control arrangement for detecting a request for a call handover and for controlling the insertion. A change of radio channels by the mobile subscriber may be detected, for example, in that no signal from the mobile subscriber arrives at the base station that hands over the call, or that a signal is received in the base station that takes over the call, respectively. For detecting a signal received in digital radio systems it is especially useful carrying out measurements of the received field strength and/or bit error rate.
The signal coming from the switching centre can easily be inserted into the signal going to the switching centre in that the switching equipment comprises switching means for serially connecting the first and the further base station. This serial connection of the first and the further base station makes it possible to realise a substantially seamless call handover by merely implementing measures lying within the range of the network infrastructure of the mobile radio system i.e. only the base stations need to be modified, while a substantially seamless handover with already existing subscriber stations is possible, thus modifications in the subscriber stations are not necessary.
There are various possibilities, in principle, including additional switching means in the switching system, to carry out the henceforth non-real-time switching operations in the switching system. The invention is especially advantageous in that the switching centre comprises switching means which are provided for separately switching through the signal coming from the switching centre and the signal going to the switching centre when a call handover is effected. Consequently, for effecting a call handover, an incoming and an outgoing line are switched separately in the switching system, so that no additional switching means in the switching system are necessary, but only the operating program of the switching system needs to be modified accordingly. The otherwise customary pairwise line switching in a switching system is performed in two separate switching operations. Before the final (pairwise) switching operation, an incoming transmission line of one line circuit (for example, the line circuit coming from the base station that hands over the call) is connected to the outgoing transmission line of the other line circuit (for example, of the line circuit leading to the base station that takes over the call). In this manner a loop in the switching system is closed between the line circuit that hands over the call and the line circuit that takes over the call.
An advantageous multistage call handover may be effected in that, in a first step, the switching means of the switching centre and the switching means of the switching equipment of the further base station are provided to switch a send signal coming from the fixed network and to be sent to a mobile station through to the first base station via the further base station after a request for a call handover, in that, in a second step, the switching means of the switching equipment of the first and of the further base station are provided to switch a receiving signal for a call handover received from the mobile station through to the further base station via the first base station, and in that, in a third step, the switching means of the switching centre are provided to switch the receiving signal received from the mobile station through to the fixed network.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
BRIEF DESCRIPTION OF THE DRAWING
In the drawings:
FIGS. 1a, b, c show an illustrative embodiment for a mobile radio system comprising three different phases of a call handover,
FIG. 2 shows the structure of a cellular mobile radio system,
FIG. 3 shows an illustrative embodiment for a base station for a mobile radio system,
FIG. 4 shows the diagrammatic structure of a signal processing unit of a base station, and
FIGS. 5a to 5j give diagrammatic representations of a further illustrative embodiment of a mobile radio system with various phases of a call handover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1a, 1b, 1c show illustrative embodiments for a mobile radio system comprising three different phases of a call handover. The mobile radio system shown in the drawing FIGS. 1a, 1b, 1c comprises a first base station FS1, a further base station FS2, a switching centre SW1 as well as a mobile station MS. In the illustrative embodiment shown in the drawing FIGS. 1a, 1b, 1c are shown only the parts of the mobile radio system that are relevant to the invention. For example, the transmitting section of the mobile station and of the first and further base station FS1, FS2 are referenced TX, whereas the receiving sections are referenced RX. The first and the further base station FS1, FS2 additionally comprise each switching equipment CD which includes switching means S R , S T as well as a detection and control arrangement Det for controlling the switching means S R , S T . The switching centre SW1 comprises switching means SW R , SW T which are provided for separately switching through the send signal S FT coming from a fixed network FN or a signal S FR transmitted to the fixed network. A signal coming from the switching centre SW1 and arriving at the first base station FS1 is referenced S k1 , whereas the signal going from the first base station FS1 to the switching centre SW1 is referenced S g1 . Accordingly, the signals in FIG. 1b or FIG. 1c between the further base station FS2 and the switching centre SW1 are referenced S g2 and S k2 .
The object of the switching means S R , S T , SW R , SW T , SW RT in the further base station FS2 and in the switching centre SW1 is to establish a serial connection of the first base station FS1 and the further base station FS2. When a call is handed over then, the signal S k coming from the switching centre SW1 and the signal S g going to the switching centre SW1 are then to be switched through separately. This provides a multistage switch-over during the call handover, which will be further explained in the following with reference to the various switch-over phases shown in the drawing Figures 1a to 1c.
FIG. 1a shows the phase in which the mobile station MS is located within reach of the first base station FS1 assigned to a first cell. For this purpose, the switching means SW R , SW T of the switching centre SW1 are arranged in such a way that the send signal S FT coming from the fixed network FN and destined for the mobile station MS is switched as an incoming signal S k1 to the transmitter TX of the first base station FS1. The transmitter TX of the first base station FS1 transmits this signal to the mobile station MS which is symbolized by the arrow pointing towards the mobile station MS. Similarly holds for the reverse direction of transmission i.e. a send signal transmitted by the transmitter TX of the mobile station MS is received by the first base station FS1 via the receiver RX and transferred as an outgoing signal S g1 via the switching centre SW1 as a receiving signal S FR to the fixed network FN.
When the mobile station MS gradually moves outside the range of the cell which is covered by the first base station FS1 into the direction of the cell covered by the further base station FS2, for example, on the basis of a "handover required" command as described with respect to the FIG. 5, the switching centre SW1 no longer directly transfers the send signal S FT coming from the fixed network to the first base station FS1, but the switching means SW T , SW RT are moved to such a position that the send signal S FT is transferred to the further base station FS2 as a signal S k2 coming from the switching centre SW1, whereas the switching means S T , S R of the switching equipment CD of the further base station FS2 are arranged such that send signal S FT is transferred both to the transmitter TX of the further base station FS2 and, as an outgoing signal S g2 , to the switching centre SW1. The switching means SW RT of the switching centre SW1 transfers this signal as an incoming signal S k1 to the transmitter TX of the first base station FS1. In the phase of the call handover shown in FIG. 1b there is thus a serial connection of the first and the further base station FS1, FS2 for the send signal S FT .
FIG. 1c shows the serial connection of the base stations FS1, FS2 during the call handover, after the mobile station has switched over to the further base station FS2. In this operating state, the send signal S FT coming from the fixed network FN is switched through as an incoming signal S k2 to the transmitter TX of the further base station FS2 and transmitted by that base station to the mobile station. The signal transmitted by the transmitter TX of the mobile station MS to the further base station FS2 is received by the receiver RX of the further base station FS2 and switched through via the switching means S R of the switching equipment CD as an outgoing signal S g2 to the switching centre SW1 and, via the switching means SW RT , as an incoming signal S k1 coming from the switching centre to the first base station FS 1 . The switching means S T , S R of the switching equipment CD of the first base station FS1 are switched in such a way that this signal S k1 is transferred as an outgoing signal S g1 from the first base station FS1 to the switching centre SW1 and is transferred from there via the switching means SW R as a receiving signal S FR to the fixed network. In a last step the switching means SW RT as well as the switching means SW R of the switching centre SW1 are switched in such a way that the signal S g2 going from the further base station FS2 to the switching centre SW1 is fed directly to the fixed network FN as a receiving signal S FR . This is no longer specifically shown in FIGS. 1a to 1c.
The principle of a call handover proposed in the FIGS. 1a to 1c may also be carried out in existing mobile stations, because no modifications of the mobile stations are necessary. Modifications for such a handover are only necessary in the network infrastructure, in that the mobile stations take part in a handover, can be arranged in a serial connection. This serial connection comprises a duplex channel which can be separately switched for send and receive directions and thus supplies the same information to all the base stations that take part. The network configuration proposed in FIGS. 1a to 1c is dynamically allocated in several network nodes (switching equipment CD, switching centre SW1) by conventional one-way switches. Compared with network configurations known thus far, only the switching equipment CD with the switching means S R , S T is necessary, which make the transfer in the downlink and uplink directions in the base stations FS1, FS2 possible. As a result, the base station FS1 becomes transparent to data supplied by the network.
With the configuration proposed in FIGS. 1a to 1c, when a handover is initialized, all the base stations are supplied with the same downstream data which may also be fed to the respective downlink channels. Only in the serving base station FS1, the switching means S R , S T are open in this operating phase (compare FIG. 1b) between downlink and uplink, so that in the first base station FS1 a continuable uplink signal can be detected, which causes the take-over base station FS2 to connect the terrestrial channels to the respective radio channels.
When the mobile station MS receives the command to change to the new radio channel of the take-over base station FS2, it may accordingly access this channel in synchronism or out of synchronism. At this moment the base station FS1 handing over the call will lose the signal of the mobile station MS which causes the uplink/downlink connection of the switching equipment CD of the base radio station FS1 to be connected through (compare FIG. 1c). In the mean time the former destination base station will detect that the mobile station FS occupies the assigned channel and will thus immediately switch the channels through. The result of this multistage switching operation as shown in FIGS. 1a to 1c is an instantaneously switched radio path without delay times and without ambiguous channel combinations. On the whole, the proposed handover considerably improves the transmission quality even for data transmissions.
The FIGS. 1a to 1c show a handover taking place between two base stations FS1, FS2 which are both assigned to the same switching centre SW1. In the case where a handover takes place between a base station, a first switching centre and a base station that is assigned to a further switching centre, it is necessary to perform the same switching operations as are necessary in the illustrative embodiments described with respect to FIGS. 1a to 1c in the base stations that take part. Only in the participating switching centres of the handover and take-over base stations is it necessary in this case to arrange respective transmission paths, so that the principle shown in FIGS. 1a to 1c of a serial connection of the call handover and the call take-over base station can take place.
FIG. 2 shows the structure of a cellular mobile radio system. As an illustrative embodiment was selected the GSM system (Global System for Mobile Communication) already operated in Europe. A survey of this mobile radio system is to be found in EP 0 544 457 mentioned before. As the GSM network is sufficiently known to a person skilled in the art, the GSM network will only be discussed in detail in the course of the description of the invention in so far this is necessary for understanding the invention. Furthermore, the invention is obviously not restricted only to the GSM network, but also suitable for all other mobile radio systems in which a call handover takes place.
The skeleton of the GSM network is formed by mobile switching centres MSC 2, 3 which are mutually connected via data lines. The mobile switching centre MSC is a high-efficiency digital switching centre which establishes both the transition between the GSM network 1 and other telecommunication networks such as, for example, a public telephone network 17 (PSTN), the ISDN network, and so on, and manages the GSM network 1. One or more base station controllers BSC are connected to each mobile switching centre MSC. The base station controller BSC in its turn manages one or more base stations 10 . . . 15 (BTS) while each base station BTS serves a radio cell. For establishing the respective connections between the mobile switching centre MSC and each base station BTS, each base station controller BSC comprises a further switch. For the principle of the invention it is not necessary to make a distinction between mobile switching centre MSC and base station controller BSC.
The transition from the mobile switching centre MSC to the base station controller BSC is normalized as a so-called A-interface. The A-interface provides the known PCM30 data format, so that PCM30 transmission links suitable for data transmission can be used. The PCM30 signal is a time-division multiplex signal in which 30 data signals, for example, digitized telephone signals, are compressed at a data rate of 64 kbit/s to a 2.048 megabit/s bit stream. To this end the PCM 30 frame is subdivided into 32 time slots of 8 bits each. The first time slot (number 0) contains an identification of the beginning of the frame, the 17 th time slot (number 16) is used for signalling the data channels accommodated in the remaining 30 time slots.
For the first configuration layer of the GSM system, a speech coding was selected in which a 260-bit-long data block is formed based upon the known LPC technique (LPC=Linear Predictive Coding) linked with a long-term prediction (LTP) and a coding of the residual signal by a sequence of pulses in a regular time pattern (RPE--Regular Pulse Excitation) for speech samples lasting 20 ms each. This corresponds to a data rate of exactly 13.0 kbit/s. In contrast, in the cable telephone network, a pulse code modulation (PCM) at a data rate of 64 kbit/s is customary for the digital transmission of speech signals. For encoding PCM signals into GSM signals and vice versa, there is provided transcoder equipment (TCE). The 260 coherent bits of a 20-ms-long speech sample will be referenced net bits in the following, because they do not contain any further information. These net bits are extended by additional control bits and empty bits to a total of 320 bits and thus form a so-called TRAU frame (TRAU--Transcoding Rate Adaptation Unit). The data rate of the TRAU frame is thus exactly 16 kbit/s.
For the implementation of the invention it is advantageous, albeit not strictly necessary, that a type of payload signal coding is used between switch and participating base stations.
Although in GSM the transcoder equipment TCE 4, 5 forms a logical part of the base station controller BSC, this equipment may be located at various positions, for example, even at the mobile switching centre MSC. On the transmission paths between the transcoder equipment TCE and the base station central equipment BCE 6, . . . , 9, in this manner only one quarter of the transmission capacity is necessary, because each PCM30 channel having a rate of 64 kbit/s can simultaneously accommodate four TRAU signals at 16 kbit/s. Since the distance between mobile switching centre MSC and base station central equipment BCE may be more than several 100 km, it is possible to save on transmission cost in this manner.
For transmitting data between the base station central equipment BCE and the individual base stations BTS (so-called A bis interface), also a PCM30 frame is provided, while the PCM30 frame contains logical sub-channels, so that 16 kbit/s transmission capacity is available for each traffic channel.
FIG. 3 shows the diagrammatic structure of a base station BTS. In a line concentrator unit LCU, payload signals and control signals in the data stream coming in via the A bis interface are separated. The payload data coming in over an internal data bus of the base station BTS are distributed over individual radio terminals RT1 . . . RT4, while each radio terminal RT has its own radio frequency. As the GSM system is conceived as a TDMA system having eight time slots for one frequency, one radio terminal RT can provide eight transmission channels. A signal processing unit SPU arranged in the radio terminal RT forms time slot send signals from the respective payload data, which signals are modulated in a transmitter unit TXU on a HF carrier also generated in the transmitter unit and are brought, as required, to an appropriate output transmitter power in a high power amplifier HPA. Via antenna coupling equipment ACE, the send signals from all the radio terminals RT of a base station BTS are combined to a single send signal.
The signals received from an aerial are selected according to frequency in the receiver unit RXU of the radio terminal RT and transformed into complex, digital baseband signals. The baseband signals are decoded in the signal processing unit SPU and combined to a continuous data stream and transmitted via the internal data bus and the line concentrator unit LCU via the A bis interface to BCE (compare FIG. 2).
The receiver unit RXU further measures the respective receive field strength of the received signal and transfers the received field strength to a radio terminal controller RTC. When the received signal is decoded, the signal processor SPU also determines the bit error rate and derives therefrom a quality information signal. The radio terminal controller RTC collects the quality information of the received signal and the received field strengths and computes a mean value thereof. These data which are important to the handover decision are transferred to the line concentrator unit LCU separately from the payload data and transmitted in a signalling channel of their own to the base station controller BSC (see FIG. 2).
For generating a central clock signal, each base station further includes an internal control unit BCU (BTS-central unit).
FIG. 4 shows the basic structure of a signal processing unit SPU. The internal data bus of the base station BTS is formed by a first data bus 301 which carries the data signals arriving via the A bis interface, and a second data bus 302 which carries the data leaving via the A bis interface. A coder 304 included in the signal processing unit SPU controls a first interface 303, so that the data destined for a respective radio channel are taken over by the internal data bus 301. The data that have been taken over are buffered in a first memory 305 by the coder 304 in accordance with the respective radio channel i.e. in accordance with the time slot in which they are to be transmitted. For this purpose, the payload data still available in the TRAU frame are extracted. The coder 304 adds additional data bits to the 260 bits of a 20 ms speech sample for an error detection and this total is expanded to 456 bits via a convolutional coding, which provides considerable protection against transmission errors. From these 456 bits are formed eight sub-blocks of 57 bits each. In each time slot are transmitted a sub-block of a TRAU frame and a respective sub-block of the next TRAU frame, so that after eight TDM frames a total of two TRAU frames are transmitted. This interleaving spreads the gross bits of a 20 ms speech sample over eight successive TDMA frames, so that the signal becomes less sensitive to brief disturbances, but the resultant transmission delay, however, does not become too large. Similarly, also signalling data having a net length of 184 bits are transmitted in gross lengths of 456 bits.
To form time slot signals, the coder inserts between the transmit sub-blocks which have 57 bits each a training sequence that contains a specific 26-bit-long bit pattern as well as two further signalling bits (stealing flags), and three more initial and end bits at the beginning and end of the time slot signal. The data block formed in this manner for each of the eight time slots and lasting 148 bits is sent on time to the transmitter unit TXU by the coder 304.
The received signals baseband-coded by the receiver unit RXU are converted in an equalizer 306 into sample values for each bit to be decoded. A decoder 307 computes from these sample values the received data blocks for each time slot, de-interleaves the sub-data blocks and forms therefrom TRAU frames again. For timely transmitting these TRAU frames via a second interface controller 309, the computed TRAU frames are buffered in a second memory 308.
Certain commands transmitted to the mobile radio station are so-called transparent data i.e. the base station transmits these data to the mobile station without evaluating these data. Such a transparent command is also called a handover command which is sent by the base station controller BSC to the mobile station to instruct the mobile station to continue the transmission over another radio channel, that is to say, in another radio cell. The structure of the handover command is laid down in GSM Recommendation 0.4.08, chapter 9.1.14. On the basis of a specific bit pattern at the respective locations in the handover command, the handover command may be unambiguously distinguished from other control commands. For example, the second byte denoting the message type has the bit sequence "0010111". The handover command further contains important data for the mobile station, such as, the radio channel to be used.
In the illustrative embodiment, the coder 304 is arranged in such a way that it is capable of detecting a handover command on the basis of the particular bit sequence. The coder 304 is further arranged so that the moment it has detected a handover command for a specific radio channel i.e. for a specific time slot, it transmits the number of this time slot to the decoder 307. The decoder 307 in the illustrative embodiment is arranged in such a way that each time a received TRAU frame from the second memory 308 should be transferred to the interface 309, the decoder does not use this frame, but the TRAU frame received from the base station controller BSC and buffered in the first memory 305.
Thus, the moment a handover command is detected, in lieu of the TRAU frames received from the mobile subscriber for the respective radio channel, the TRAU frames coming from the base station controller BSC and intended for the mobile subscribers are returned to the base station controller BSC. Other criteria for using these procedures are, for example, the evaluation of signals received from the mobile radio station especially with respect to contents, receiving level or receiving quality.
When a call handover is required by its base station controller BSC, the base station taking over the call selects a free radio channel and waits until the mobile subscriber station reports itself on this radio channel. In the illustrative embodiment the decoder 307 is arranged in such a way that, from the moment a new radio channel is rendered available for a call handover until a handover access is detected, the mobile station returns to the respective base station controller BSC all the TRAU frames received from the coder 304 for this radio channel. The moment the decoder 307 detects a valid access to this radio channel, the data received from the mobile subscriber station are conventionally transmitted in TRAU frames to the base station controller. In this way the data stream intended for a specific radio channel and coming from a base station controller is returned to the base station controller in lieu of data (not yet) received from a mobile station.
In the following the cooperation of the depicted embodiments of the base stations and a switching system included therein will be described for the case of a call handover. The mobile station continuously measures the level and quality of the signals which are received from its own base station as well as from neighbouring base stations. The evaluated data are sent to the base station controller BSC by the mobile station. Irrespective of this, also the base station BTS measures the level and receiving quality of the mobile stations which values are then sent to the respective base station controller. In addition, the GSM system also provides a measurement of the distance from the mobile station to the base station. In either case the base station controller processes the data and decides whether a call handover is to be effected or not. If the call handover is to take place, the respective base station controller BSC computes the preferred base station to which the call is to be handed over.
Depending on which base station controller the handover base station and the take-over base station are connected to, the described mobile radio network has different procedures for the call handover. If a call handover base station and a call take-over base station are connected to the same base station controller such as, for example, the base stations 10 and 11 in FIG. 2, this is referenced an Intra BSC handover. Only the switch found in the common base station controller 6 takes part in the call handover. In the case of a call handover for which the call handover base station (for example, BTS 10) and the call take-over base station (for example, BTS 12) are connected to different pieces of base station central equipment (for example, BCE 6 and BCE 7), the call is handed over while use is made of the mobile switching centre (MSC 2) and is referenced an Inter BSC handover. The cases may then be distinguished where the participating base station controllers BSC are connected to the same mobile switching centre MSC and where the base station controllers BSC are connected to two different mobile switching centres MSC (for example, a call handover from the base station 12 to the base station 14 in FIG. 2). The call is then handled via the two mobile switching centres (MSC 2 and MSC 3).
Substitutionally for all said call handovers, there will be discussed in the following a call handover from a base station BTS-A to a base station BTS-B while use is made of only a single mobile switching centre MSC.
In this context each phase of the call handover is described with reference to FIGS. 5a-5f, while for clarity only the call paths within a switch SW, or the transmission paths which are rendered available in that call handover phase of the mobile radio system, or are actually necessary, are shown. For clarity, all the described, necessary arrangements, such as transcoder equipment TCE, switch in the base station controller BSC, line concentrator unit LCU and so on, as well as the channels along which the signalling among the stations is controlled, are omitted.
FIGS. 5a-5f symbolically show the coupling means for feeding back a data stream received from a base station, from its assigned base station controller, intended for a specific mobile subscriber on the pairwise assigned return channel from the base station to its base station controller, as a coupling device CD.
FIG. 5a shows an existing link from a network subscriber via a mobile switching centre MSC, a base station controller BSC-A and a base station BTS-A to a mobile station MS. Once the base station controller BSC wishes to introduce a call handover, it sends the corresponding command "handover required" to its mobile switching centre MSC (FIG. 5b).
In the message "handover required" is included a list of base stations to which the call is to be handed over. The respective mobile switching centre MSC then determines via what base station controller BSC what base station BTS is preferably to be accessed for the call handover. This base station controller BSC-B then comes out with the request for a call handover via a "handover request" command (FIG. 5c).
In the base station controller BSC-B which takes over the call is then searched for a free channel in the base station BTS-B and this free channel is reserved for the call handover. The coupling device CD assigned to this newly selected radio channel is switched in such a way that a signal coming in by this channel addressed to the take-over base station BTS-B from the take-over base station controller BSC-B is sent back to the take-over base station controller BSC-B. Together with the reservation of the radio channel sent to the take-over base station BTS-B, the take-over base station controller BSC-B sends back an acknowledge command "handover request acknowledge" to the mobile switching centre MSC (FIG. 5d). When the acknowledgement "handover request acknowledge" is received, the MSC lays out the transmission path to the call take-over base station BTS-B (FIG. 5e).
Furthermore, in the mobile switching centre MSC the call handover is prepared by a corresponding switching operation in the switch SW. For this purpose, the original link in the switch, by which link the signal coming from the mobile subscriber MS was transferred to the network subscriber, is stopped and instead, the signal received from the mobile subscriber is taken via the switch SW to the prepared channel to the base station BTS-B which takes over the call. The receiving path of the prepared radio channel is led to the network subscriber. As a result of the previous position of the coupling device CD in the base station BTS-B which takes over the call, the signal coming from the mobile subscriber MS is thus first, prior to being transmitted to the network subscriber, carried by the prepared link in the switch to the take-over base station BTS-B, and returned to the switch SW of the mobile switching centre MSC by the switched coupling device CD (FIG. 5f).
As the data stream is looped through, a continuous link between the subscribers is ensured up to the switching operation itself. As the switching times in the switch SW are very brief, information can hardly be lost when the switch is changed over. It is essential for the switching operation in the switch SW in preparation of the call handover that the formation of the loop is terminated by the coupling device CD in the take-over base station, before the described change of position takes place in the switch SW of the mobile switching centre MSC. Once these conditions have been fulfilled, the actual instant at which the change of the switch SW takes place is unimportant. Even rather long delay times between the arrival of the switch command and the execution of the switch command do not lead to noticeable dead times because of the continuous link of the subscribers.
After the switch of the mobile switching centre MSC has made the described change, the mobile switching centre sends out the handover command to the base station controller BSC-A handing over the call (FIG. 5g). As already described, this command is given to the base station and sent to the mobile station MS.
As has also already been described, the decoding of the "handover command" in the base station BTS-A causes the data received from the respective mobile subscribers to be returned to the base station controller BSC-A. As a result of the "handover command", the mobile subscriber station MS changes to the new radio channel of the call take-over base station BSC-B. Since the mobile subscriber station accesses the call take-over base station BSC-B, as has already been described, the coupling between the incoming and outgoing data streams in the base station is cancelled, so that the incoming data stream is sent to the mobile subscriber station MS via the transmitter unit TX of the call take-over base station, and the data stream coming from the mobile subscriber station MS is sent towards the mobile switching centre MSC via the receiver unit RX (FIG. 5h).
Henceforth the switching means CD in the call handover base station BTS-A has closed the loop from the network subscriber to the call handover base station in two directions, while the signal looped through to the call handover base station is conveyed to the call take-over base station BTS-B via the still existing call preparing circuit of the switch SW of the mobile switching centre MSC. In this manner the dead time noticeable by the subscribers during the call handover on the radio link is limited to the time between the command to the mobile subscriber station to change radio channels and the access of the mobile subscriber station to the call take-over base station, because in the described manner there is no need to carry out switching operations in the switch SW itself during the call handover.
After a successful call handover, the call take-over base station controller BSC-B sends out an acknowledgement "handover complete" to the mobile switching centre MSC. In response to this command, the final route for the two directions of the call from the network subscriber to the call take-over base station BSC-B is switched back (FIG. 5i). Due to the still existing bridge circuit of the switch element in the call handover base station BTS-A, the instant at which the switching operation in the switch SW of the mobile switching centre becomes unimportant again. The switching operation itself requires very brief switch times, so that the two subscribers hardly notice anything of the switching operation.
As a result of the acknowledgement of the successful handover "handover complete", the mobile switching centre MSC breaks off the original link to the call handover base station controller BSC-A and this base station controller its link to the handover base station BTS-A (FIG. 5j). The handover is then accomplished.
The use of switching means between the switch of the mobile switching centre and the mobile subscriber station make it possible to divide the switching operation of the switch SW during a call handover into a switching operation before the handover and a switching operation after the handover. Since the switching operation in a switch SW itself can take place without a delay, the switching operations themselves cause practically no dead time. In addition, it is of no consequence whether, when the data stream is to be sent via the two base stations as described before, the data signal coming from the call handover base station is sent via the switch to the call take-over base station, or the data signal coming from the call take-over base station is sent to the call handover base station.
|
In modem, modularly structured mobile radio systems, a call between a base station and a mobile subscriber station is to be handed over to a different base station the moment the mobile subscriber station leaves the coverage area of a base station. For this purpose, a switching system providing the route between a fixed network and the base stations is to carry out appropriate switching operations. In order to realise shortest possible dead times caused by interruptions during call handovers from one radio cell to another radio cell, a first and a further base station each comprise switching equipment for inserting a signal (S k ) coming from a switching center into a signal (S g ) going to the switching center.
| 7
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to beverage dispensers and, more particularly, but not by way of limitation, to an improved dispensing valve mounting assembly for use in beverage dispensers, that allows for mixing fluids, such as plain and carbonated water, to be interchanged without having to disassemble and/or depressurize the beverage dispenser.
2. Description of the Related Art
Typically, a beverage dispenser features several dispensing valves whereby each dispensing valve is assigned a single drink flavor. Several dispensing valves enable a beverage dispenser to feature a wide variety of drink flavors. When a particular dispensing valve is activated, beverage syrup for a desired drink flavor is mixed with either carbonated water, such as when cola is required, or plain water, such as when punch is required, before being dispensed from the valve. Thus, by placing a cup accordingly and activating a valve, the beverage dispenser dispenses the resulting drink of choice into a cup below.
Market demand often requires owners of beverage dispensers to reconfigure dispensing valves to accommodate new varieties of drink flavors or more than one dispensing valve featuring the same and, typically, the most popular drink flavor. For example, when diet cola is in high demand and punch is in low demand, a beverage dispenser once featuring diet cola, cola, and punch dispensing valves can be reconfigured to a beverage dispenser with two diet cola valves and one cola valve in an attempt to satisfy the greater demand for diet cola. In this manner, the variety of drink flavors offered by a beverage dispenser is continuously changing with changing market demand.
Unfortunately, increasing the frequency of drink flavor change increased the frequency of performing the already time consuming and laborious process of reconfiguring a beverage dispenser. In the past, each dispensing valve was connected directly to a beverage syrup source as well as directly to either a carbonated or a plain water source. As such, switching between a carbonated drink flavor and a plain water or "non-carbonated" drink flavor, such as between diet cola and punch involved disconnecting a dispensing valve from its respective sources, which were typically positioned in hard-to-reach areas within the beverage dispenser. Thus, gaining access to the carbonated and plain water sources often required disassembling much of the beverage dispenser; and, upon reassembly, pressure and flow rates had to be reset across the connection between the dispensing valve and respective sources.
The introduction of a dispensing valve mounting assembly, cooperatively linked between the dispensing valve and the beverage syrup source and carbonated water or plain water sources, greatly reduced the need to disassemble the beverage dispenser to gain access to the carbonated and plain water sources as well as reduced the need to reset pressure and flow rates upon reassembly of the beverage dispenser. In effect, a dispensing valve mounting assembly remains cooperatively linked to a beverage syrup source as well as to either a carbonated or a plain water source, especially when a dispensing valve is detached from the dispensing valve mounting assembly such as during cleaning or maintenance.
In particular, current dispensing valve mounting assemblies feature two outlets, one outlet for delivering beverage syrup to a dispensing valve and one outlet for delivering either plain or carbonated water to the dispensing valve. Current dispensing valve mounting assemblies, however, only feature two inlets, one inlet connected to a beverage syrup source and one inlet connected to either a plain or a carbonated water source. Thus, because a dispensing valve mounting assembly provides only one inlet for both plain and carbonated water, interchanging between carbonated and non-carbonated drink flavors still requires disassembling the beverage dispenser to gain access to the carbonated and plain water sources as well as resetting pressure and flow rates upon reassembly of the beverage dispenser similar to when there is no dispensing valve mounting assembly. For example, when reconfiguring a dispensing valve featuring a carbonated drink flavor to accommodate a non-carbonated drink flavor, any suitable connecting means for delivering carbonated water from the carbonated water source would first need to be disconnected from the dispensing valve mounting assembly inlet and then sealed off to retain pressure for future use. Any suitable connecting means for delivering plain water from the plain water source would then need to be connected to the inlet in a manner so that a desired pressure across the connection is maintained. Thus, current dispensing valve mounting assemblies cannot easily interchange between plain and carbonated water.
Accordingly, there is a long felt need for a dispensing valve mounting assembly that permits easy interchange between plain and carbonated water without disassembling a beverage dispenser as well as resetting the pressure and flow rates across the beverage dispenser.
SUMMARY OF THE INVENTION
In accordance with the present invention, a dispensing valve mounting assembly includes a housing having a beverage syrup inlet communicating with a beverage syrup outlet and a first mixing fluid inlet and a second mixing fluid inlet communicating with a mixing fluid outlet. The housing includes a mixing fluid cavity between the first mixing fluid inlet and the second mixing fluid inlet and the mixing fluid outlet. The housing further includes a beverage syrup cavity between the beverage syrup inlet and the beverage syrup outlet.
The dispensing valve mounting assembly further includes an inlet switch assembly. The inlet switch assembly includes a selector seal disposed in the mixing fluid cavity of the housing. The selector seal includes a first guide hole communicating with the first mixing fluid inlet, a second guide hole communicating with the second mixing fluid inlet, and an exit guide hole communicating with the mixing fluid outlet. The selector seal further includes a vent slot between the first guide hole and the second guide hole for delivering leaked first and second mixing fluid exterior to the housing.
The selector seal further includes an inlet selector disposed in the selector seal. The inlet selector includes a selection passageway having a selection opening and a selection exit aligned with the exit guide hole of the selector seal. The inlet selector is movable among a first position that interrupts alignment between the selection opening of the selection passageway and both the first guide hole and second guide hole of the selector seal, a second position that aligns the selection opening of the selection passageway with the first guide hole of the selector seal, and a third position that aligns the selection opening of the selection passageway with the second guide hole of the selector seal. The inlet selector further includes a groove for communicating leaked first and second mixing fluid to the vent slot.
The dispensing valve mounting assembly still further includes a beverage syrup valve. The beverage syrup valve includes a turn-key valve disposed in the beverage syrup cavity. The turn-key valve includes a selection passageway having a selection opening and a selection exit. The turn-key valve is movable from a first position that interrupts alignment between the selection opening of the selection passageway and the beverage syrup inlet of the housing and the selection exit of the selection passageway and the beverage syrup outlet of the housing to a second position that aligns the selection opening of the selection passageway and the beverage syrup inlet of the housing and the selection exit of the selection passageway and the beverage syrup outlet of the housing.
It is therefore an object of the present invention to provide a dispensing valve mounting assembly for use in beverage dispensers, that allows for mixing fluids, such as plain and carbonated water, to be interchanged without having to disassemble and/or depressurize the beverage dispenser.
It is a further object of the present invention to provide a dispensing valve mounting assembly that vents leaked mixing fluid to its exterior to prevent contamination between mixing fluids.
Still other objects, features, and advantages of the present invention will become evident to those of ordinary skill in the art in light of the following.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view illustrating an improved dispensing valve mounting assembly.
FIG. 2 is a perspective view illustrating the preferred inlet embodiment for the improved dispensing valve mounting assembly.
FIG. 3 is a cross-section taken along the lines a,a of FIG. 2 illustrating the preferred inlet embodiment for the improved dispensing valve mounting assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. The figures are not necessarily to scale, and some features may be exaggerated to show details of particular components or steps.
As illustrated in FIGS. 1-3, dispensing valve mounting assembly 1 includes a block 2, an inlet switch assembly 3, and a beverage syrup valve assembly 4. Furthermore, the inlet switch assembly 3 and the beverage syrup valve assembly 4 are maintained within the block 2 by a securing plate 40 that is secured to the block 2 using fasteners 48.
The block 2 defines a housing 30 which, in this preferred embodiment, has a beverage syrup inlet 36, a first mixing fluid or carbonated water inlet 32, and a second mixing fluid or plain water inlet 33 formed integrally therein, thereby creating one piece. It should be emphasized that those skilled in the art will recognize other configurations for the beverage syrup, carbonated water, and plain water inlets. The beverage syrup inlet 36, the carbonated water inlet 32, and the plain water inlet 33 are communicatively linked with a beverage syrup source (not shown), a carbonated water source (not shown), and a plain water source (not shown), respectively, using any suitable connecting means, such as conduit. Thus, in operation, beverage syrup, carbonated water, and plain water are delivered to their respective inlets under a preset pressure and at a controlled rate of flow.
In this preferred embodiment, a beverage syrup outlet 37 and a mixing fluid or plain/carbonated water outlet 34 are integrally formed within housing 30, thereby creating one piece. The beverage syrup outlet 37 and plain/carbonated water outlet 34 are communicatively linked to a dispensing valve (not shown) and, further support the dispensing valve on the block 2. In this preferred embodiment, a pair of grasping prongs 39, integrally formed with housing 30, are provided to aid the beverage syrup outlet 37 and the plain/carbonated water outlet 34 in coupling of the dispensing valve with the housing 30. In addition, in this preferred embodiment, an array of connector members 38 are formed integrally with housing 30, thereby creating one piece. The connector members 38 are provided to facilitate the coupling of the dispensing valve mounting assembly 1 with the beverage dispenser.
In operation, beverage syrup as well as plain or carbonated water are delivered from the plain/carbonated water and beverage syrup outlets 34, 37, respectively, to the dispensing valve. A dispensing valve mounting assembly thus allows for a dispensing valve to be detached therefrom, especially during cleaning or maintenance, without resetting pressure and flow rates upon reattachment as well as without disassembling a beverage dispenser.
In this preferred embodiment, housing 30 defines both a beverage syrup cavity 35, which receives the beverage syrup valve assembly 4 therein, and a mixing fluid or plain/carbonated water cavity 31, which receives the inlet switch assembly 3 therein. The beverage syrup cavity 35 is communicatively linked with the beverage syrup inlet 36, whereby beverage syrup flows from the beverage syrup inlet 36 through an opening 36a provided by the beverage syrup cavity 35 and formed within housing 30. (See FIG. 3). In addition, the beverage syrup cavity 35 is communicatively linked with the beverage syrup outlet 37, whereby beverage syrup flows from the beverage syrup cavity 35 through an opening 37a provided by the beverage syrup cavity 35 and formed within housing 30. Ultimately, the flow of beverage syrup through the beverage syrup cavity 35 is dictated by the positioning of the beverage syrup valve assembly 4 with respect to the openings 36a, 37a.
In a similar manner, the plain/carbonated water cavity 31 is communicatively linked to both the carbonated water inlet 32 and the plain water inlet 33. In particular, carbonated water flows from the carbonated water inlet 32 through a carbonated water channel 32a defined by housing 30. Likewise, plain water flows from the plain water inlet 33 through a plain water channel 33a defined by housing 30. It should be added that copper conduit often delivers plain water to beverage dispensers. In this instance where copper conduit is employed, carbonated water must flow through its own pathway, independently from a plain water pathway, due to potentially bio-hazardous byproducts which result from carbonated water chemically reacting with copper. As is discussed further below, dispensing valve mounting assembly 1 is configured to, but is not limited to, compensate for instances where copper conduit is used.
As such, the plain/carbonated water cavity 31 is communicatively linked with the plain/carbonated water outlet 34, whereby plain or carbonated water flows from the plain/carbonated water cavity 31 through an exit channel 34a defined by housing 30. Ultimately, the flow of either plain or carbonated water through the plain/carbonated water cavity 31 is dictated by the positioning of the inlet switch assembly 3 with respect to either the carbonated water channel 32a and the exit channel 34a or the plain water channel 33a and the exit channel 34a.
The inlet switch assembly 3 includes a selector seal 6 and an inlet selector 5 disposed within the selector seal 6. The selector seal 6, in turn, includes a body 16 having an exterior surface 16a and an interior surface 16b. In this preferred embodiment, the selector seal 6 includes a pair of opposing guide holes 17 defined by body 16. (See FIG. 3). In this preferred embodiment, the selector seal 6 includes a pair of opposing protrusions 18 formed by exterior surface 16a. (See FIG. 1). Each protrusion 18, in turn, defines a vent slot 19 formed along interior surface 16b. In this preferred embodiment, selector seal 6 includes an exit guide hole 17a defined along the bottom portion of the selector seal 6. (See FIG. 3).
Accordingly, the selector seal 6 is positioned within the plain/carbonated water cavity 31 such that one guide hole 17 is in communication with the carbonated water channel 32a, the opposing guide hole 17 is in communication with the plain water channel 33a, and the exit guide hole 17a is in communication with the exit channel 34a. In addition, a pair of opposing recesses 18a defined by the surface of the plain/carbonated water cavity 31 are provided to accommodate the pair of opposing groves 18 matedly positioned therein. (See FIG. 2).
The inlet selector 5 includes a selector body 12 and a selector turn dial 10 positioned above the selector body 12 to allow rotational movement of the selector body 12 in tandem with the manual engagement of the selector turn dial 10. (See FIG. 1). In particular, the inlet selector 5 further includes a base 11 that is secured, using any suitable means, to the selector body 12 and to the selector turn dial 10. In operation, upon manual engagement of the selector turn dial 10, the base 11 travels against a guide slot 31a defined by the upper portion of the plain/carbonated water cavity 31. In this manner, the rotational movement of the inlet selector 5 is restricted by the length of the guide slot 31a so that, ultimately, carbonated water and plain water within their respective inlets, 32, 33, will not be intermixed, thus, reducing the risk for the creation of potentially biohazardous byproducts. (See FIG. 2).
The inlet selector 5 includes a selection passageway 13 having one selection opening 13a and one selection exit 13b. Upon manual engagement of the selector turn dial 10, the selection opening 13a operatively aligns with either one of the two guide holes 17 to thus complete a path for either plain or carbonated water to pass therethrough and flow out the selection exit 13b, through the exit guide hole 17a, and to the exit channel 34a . (See FIG. 3). In effect, the selection passageway 13 allows for plain and carbonated water to be easily interchanged within the dispensing valve mounting assembly 1 without having to disassemble and depressurize the entire beverage dispenser.
Furthermore, the inlet selector 5 includes a collector groove 14 formed in the bottom portion of the selector body 12 and defined by the bottom portion of the selector body 12 and the selector seal 6. The collector groove 14, in the event of a leak, acts to direct any residual plain and/or carbonated water that may have seeped between the inlet selector 5 and the selector seal 6 toward each vent slot 19. Residual plain and/or carbonated water travels up the vent slot 19, under pressure, until it has vented and escaped into the atmosphere. In particular, the collector groove 14 is coupled with the lower interior surface 16b to form an integral collection chamber (not shown) through which residual plain and/or carbonated water is directed toward and out each vent slot 19. The collector groove 14 acts to isolate plain water and carbonated water from one another to prevent cross-contamination so that carbonated water cannot seep back into the plain water inlet 33 and, thus, increase the risk of creating bio-hazardous byproducts.
The beverage syrup valve assembly 4 includes a turn-key valve 7, an o-ring seat 24 defining an aperture 25 through which the turn-key valve 7, in part, rests, and a gasket connector 27 intermediate turn-key valve 7 and opening 37a to facilitate the flow of beverage syrup therethrough. (See FIGS. 1 and 3). The turn-key valve 7 includes a beverage syrup valve body 22 and a beverage syrup turn dial 20 positioned above the beverage syrup valve body 22 to allow rotational movement of the beverage syrup valve body 22 in tandem with the manual engagement of the beverage syrup turn dial 20. (See FIG. 1). The turn-key valve 7 further includes a base 21 that is secured, using any suitable means, to the beverage syrup valve body 22 and to the beverage syrup turn dial 20. In operation, upon manual engagement of the beverage syrup turn dial 20, the base 21 travels against the surface defined by the upper portion of the beverage syrup cavity 35. In this manner, the rotational movement of the turn-key valve 7 allows for a passageway between the beverage syrup inlet 36 and beverage syrup outlet 37 to be selectively opened and closed.
In particular, the turn-key valve 7 includes a ball valve 23 disposed at the end of the beverage syrup valve body 22. The ball valve 23 defines a cavity passageway 26. Upon manual engagement of the beverage syrup turn dial 20, the cavity passageway 26 operatively aligns with the opening 36a for the beverage syrup inlet 36 and with the opening 37a for the beverage syrup outlet 37 to thus complete a path for beverage syrup to pass therethrough. In a similar manner, the path can be closed by manually adjusting the turnkey valve 7 so that the cavity passageway 26 and openings 36a and 37a are operatively out of alignment such that beverage syrup can no longer flow therethrough.
Illustratively, for a dispensing valve featuring punch drink flavor, the dispensing valve mounting assembly 1 operates in the following manner. Plain water is delivered across any suitable connecting means, such as conduit, to the plain water inlet 33 from the plain water source, by pumps (not shown) located within the beverage dispenser.
Plain water is directed from the plain water inlet 33 across the plain water inlet channel 33a to guide hole 17 defined by selector seal 6. As such, plain water flows from guide hole 17, through selection opening 13a, and across the selection passageway 13 of inlet selector 5. In this illustration, as clearly shown in FIG. 3, it should be emphasized that the selection passageway 13 of inlet selector 5 has been positioned so that it is in communication with the plain water channel 33a. Moreover, any residual plain water is allowed to depressurize and bleed-out from the dispensing valve mounting assembly 1, via the collector groove 14 and vent slot 19 configuration of the inlet switch assembly 3. For carbonated beverages, carbonated water would vent in the same manner as described for plain water.
Accordingly, plain water flows from selection passageway 13, through selection exit 13b, out exit guide hole 17a of selector seal 6, and into exit channel 34a. Plain water is directed through exit channel 34a, out plain/carbonated water outlet 34, and into the dispensing valve where plain water is mixed with punch-flavored beverage syrup to form the desired punch beverage.
As plain water is delivered from the plain water source, punch-flavored beverage syrup is delivered across any suitable connecting means, such as conduit, to the beverage syrup inlet 36 from the beverage syrup source, by pumps (not shown) located within the beverage dispenser. Punch-flavored beverage syrup is directed from the beverage syrup inlet 36 to the opening 36a. In this illustration, as clearly shown in FIG. 3, it should be emphasized that turn-key valve 7 is communicatively linked with the opening 36a to the cavity passageway 26 and with the opening 37a to the beverage syrup outlet to thus complete a path for beverage syrup to pass therethrough. As such, punch-flavored beverage syrup is directed from opening 36a across the cavity passageway 26, and to opening 37a. Punch-flavored beverage syrup is directed through the opening 37a, out beverage syrup outlet 37, and into the dispensing valve that is coupled with the dispensing valve mounting assembly 1.
As discussed above, a critical feature of a dispensing valve mounting assembly is to enable switching between a carbonated and a non-carbonated drink flavor without depressurizing and disassembling the entire beverage dispenser. Illustratively, to interchange punch, a beverage requiring plain water and punch-flavored beverage syrup, with root beer, a beverage requiring carbonated water and root beer-flavored beverage syrup, the dispensing valve mounting assembly 1 is reconfigured in the following manner.
To interchange punch-flavored beverage syrup for root beer-flavored beverage syrup, turn-key valve 7 is manually rotated so that beverage syrup can no longer operatively flow across cavity passageway 26 to effectively close cavity passageway 26. The punch-flavored beverage syrup source is exchanged for a root beer-flavored beverage syrup source. The turn-key valve 7 is manually rotated so that beverage syrup can operatively flow across cavity passageway 26 to effectively open cavity passageway 26. The dispensing valve is then activated until a consistency of root beer-flavored syrup is obtained so as to initially flush-out residual punch-flavored beverage syrup entirely from the dispensing valve mounting assembly and beverage dispenser.
To interchange plain water for carbonated water, inlet selector 3 is manually rotated until selection passageway 13 is in communication with carbonated water channel 32a and is no longer in communication with plain water channel 33a. Currently, to interchange plain for carbonated water, beverage dispensers with dispensing valve mounting assemblies are disassembled to gain access to the plain and carbonated water sources and their respective connecting means to the block 2. The connecting means to the plain water source is sealed off to ensure that pressure is maintained until such connecting means is once again operational. Accordingly, as the selection opening 13a rotationally advances from the plain water channel 33a to the carbonated water channel 32a, the surface of the selector body 12 where the selection opening 13a is not present seals off plain water within the plain water channel 33a for future use without the need for disassembling the beverage dispenser. Furthermore, leaks and seepage of carbonated and/or plain water from the carbonated and plain water channels 32a, 33a, respectively, are accounted for and disposed of by the collector groove 14 and vent slot 19 configuration of the inlet switch assembly 3.
Although the present invention has been described in terms of the foregoing embodiment, such description has been for exemplary purposes only and, as will be apparent to those of ordinary skill in the art, many alternatives, equivalents, and variations of varying degrees will fall within the scope of the present invention. That scope, accordingly, is not to be limited in any respect by the foregoing description, rather, it is defined only by the claims that follow.
|
A dispensing valve mounting assembly includes a housing having a beverage syrup inlet communicating with a beverage syrup outlet and a first mixing fluid inlet and a second mixing fluid inlet communicating with a mixing fluid outlet. The dispensing valve mounting assembly further includes a beverage syrup valve assembly disposed in the housing. The beverage syrup valve assembly is movable from a first position that interrupts communication between the beverage syrup inlet and the beverage syrup outlet to a second position that permits communication between the beverage syrup inlet and the beverage syrup outlet. The dispensing valve mounting assembly still further includes an inlet switch assembly disposed in the housing. The inlet switch assembly moves among a first position that interrupts communication between both the first mixing fluid inlet and the second mixing fluid inlet and the mixing fluid outlet, a second position that interrupts communication between the second mixing fluid inlet and the mixing fluid outlet and permits communication between the first mixing fluid inlet and the mixing fluid outlet, and a third position interrupts communication between the first mixing fluid inlet and the mixing fluid outlet and permits communication between the second mixing fluid inlet and the mixing fluid outlet.
| 1
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to microbial processes for converting codeine to 14-hydroxycodeine and more particularly to such processes by means of culturing codeine with bacteria of the genus Streptomyces.
2. Prior Art
Codeine, morphine, and thebaine are natural alkaloid products of the opium poppy, Papaver somniferum. Thebaine is used to prepare a number of commercially important narcotic antagonists and agonist/antagonist analgesics by its chemical modification. Use of codeine and morphine as starting materials is also desirable but appropriate chemical routes for their use have not yet been perfected. A major requirement for the use of these three opium alkaloids for the production of some analgesics and/or narcotic antagonists is the addition of a hydroxyl group in the C-14 position. The present invention provides the first known microbial process for converting codeine to 14-hydroxycodeine with yields and efficiencies of conversion to make the process commercially feasible.
Microbial conversions of alkaloids has been known for about 25 years. Tsuda et al., Microbial Transformation of Steroids and Alkaloids, 167-193, 1964, in the publication of the I. A. M. symposium on Microbiology, Institute of Applied Microbiology. (no. 6), University of Tokyo, disclose that 120 thebaine converting strains were selected from 1700 different bacterial and fungal strains tested for that ability. Most of the 120 strains were from the basidiomycetes, especially from the wood rot fungi Trametes sanguinea. Conversions of thebaine to 14-hydroxycodeinone and 14-hydroxycodeine were disclosed. Yields of the products depended on the nutrient solution used for cultivation of the organisms.
Yamada et al., Chemical and Pharmaceutical Bulletin 10, 981-984, 1962, disclose that Trametes sanguinea was unable to convert morphine or codeine to identifiable oxidation products.
Groger et al., Experentia 25, 95-96, 1969, disclose that most of 35 strains of Trametes of European origin could convert thebaine to 14-hydroxycodeinone and various other products. Detailed accounting was not disclosed; however, 14-hydroxycodeine was found only occasionally, in trace amounts.
Liras et al., Developments in Industrial Microbiology, 16, 401-405, 1975 disclose the transformation of morphine and codeine by bacteria of the genus Arthrobacter. Morphine was transformed to 14-hydroxymorphine and an unidentified product. Codeine also was transformed into two products, the minor component of which was codeinone. The major transformed product was not identified but it was not 14-hydroxycodeine, 14-hydroxycodeinone, 14-hydroxydihydrocodeinone, or norcodeine.
Liras et al., Applied Microbiology, 30, 650-656, 1975, disclose bacterial enzyme preparations from Pseudomonas testosteroni which transformed morphine in relatively low yield to 14-hydroxymorphinone and an unidentified product. The enzyme preparations converted codeine to codeinone and 14-hydroxycodeinone.
Sewell et al., Applied Microbial Biotechnology, 19, 247-251, 1984, disclose that two species of Streptomyces and several strains of the fungus Cunninghamella transformed codeine by N-demethylating the N-methylpiperidine moiety.
Rosazza et al., Journal of Medicinal Chemistry, 18, 791-794, 1975, disclose two species of Streptomyces and several other types of microorganisms that selectively cleave either the 10-methoxy or the 11-methoxy ether groups from 10,11-dimethoxyaporphine. Soybean meal was used for the cultivation of these organisms.
Kunz, D. A., Abstracts of the Annual Meeting of the American Society of Microbiology, page 247, Feb. 25, 1985, discloses that Streptomyces griseus ATCC 10137 could catalyze a 4% molar conversion of codeine into 14-hydroxycodeine and norcodeine.
SUMMARY OF THE INVENTION
According to the present invention, provided is a microbial process for preparing 14-hydroxycodeine which comprises contacting codeine, or a water-soluble salt thereof, with bacteria of the genus Streptomyces for a period of at least about 3 days while said bacteria are being aerobically cultured in a rich medium; and recovering 14-hydroxycodeine from the medium.
When the medium is enriched with soybeam flour and when codeine is present in concentrations less than about 5 mM or preferably less than about 2.5 mM, 14-hydroxycodeine is preferentially produced in good yield. It is preferred that cultivation be carried out for a period of about 3 to 30 days, preferably about 10 to 20 days.
BRIEF DESCRIPTION OF THE DRAWING
The drawing is a graph showing the results from Example 13.
DETAILED DESCRIPTION OF THE INVENTION
The following is a list of the bacteria which transform codeine along with their source:
S. griseus: NRRL B8090
S. griseus: ATCC 10137
S. griseus: ATCC 23337
S. griseus: ATCC 13968
S. griseus: ATCC 21897
S. griseolus: ATCC 3325
S. griseolus: ATCC 11796
S. punipalus: NRRL 3529
S. lincolnensis: ATCC 25466
S. species: WH 110
The preferred bacteria derive from Streptomyces griseus that are on deposit in the Northern Regional Research Laboratory with accession number NRRL B8090. These bacteria are preferred because they convert codeine efficiency and in good yield, and produce a lower amount of norcodeine or other conversion products. Of course, if larger amounts of norcodeine are desired, one of the other strains of S. griseus can be used in an appropriate rich medium.
The bacteria are cultured and the biotransformation process carried out in a rich medium. A rich medium is well known to those skilled in the art. In general it means that all growth nutrients (e.g. carbon, nitrogen, and the energy source plus growth factors) are supplied in excess with the exact chemical composition being unknown.
COMPOSITION OF BACTERIAL MEDIA
The following is a list of preferred bacterial rich media and the compositions thereof:
Soybean Flour Medium (SFM):
Yeast extract: 5 g/L
Soybean flour: 5 g/L
K 2 HPO 4 :5 g/L
NaCl: 5 g/L
Glycerol: 20 g/L
Deionized water: 1 L
pH 6.8 (adjusted with 5N HCl)
Yeast Malt-extract Medium (YM):
Yeast extract: 3 g/L
Malt extract: 3 g/L
Bacto-Peptone: 5 g/L
Bacto-Dextrose: 10 g/L
Deionized water: 1 L
pH 6.1 (adjusted with 5N HCl)
Yeast Malt-extract Medium with 1-tyrosine (YMT):
YM
L-tyrosine: 2-5 mM
pH 6.1 (adjusted with 5N HCl)
Sporulation Medium (SpB):
Yeast extract: 1 g/L
Beef extract: 1 g/L
Tryptose: 2 g/L
Glucose: 10 g/L
FeSO 4 : 0.05 g/L
Deionized water: 1 L
pH 7.2 (adjusted with 5N HCl).
Bacto-Agar can be added to the above media in the concentration of 20 g/L to make YM or SpB agar and is used for culture maintenance. All media are sterilized prior to inoculation with bacteria by using conventional procedure, such as autoclaving them for 20 minutes at about 120° C.
Of the above, soybean flour medium is preferred because it gives better yields of 14-hydroxycodeine.
The 14-hydroxycodeine product is recovered from the medium using conventional techniques. Such techniques include extraction into an organic solvent and purification by column chromatography.
14-Hydroxycodeine is an intermediate which can be useful in preparing the commercial pharmaceutical compounds naltrexone, naloxone, oxycodone, nalbuphine, and oxymorphine. For example, 14-hydroxycodeine can be converted to oxycodone by reduction of the 7,8 double bond and oxidation of the 6-αhydroxy group to the ketone.
BACTERIAL CULTURE CONDITIONS
Bacteria were subcultured from stock cultures which were kept frozen at -65° C. in medium containing 8 percent dimethylsulfoxide, or from stock cultures stored at 4° C. on YM or SpB agar slants.
To prepare first stage cultures, a loopful--using an inoculating needle--of bacterial cells was inoculated into 5 mL of SpB and grown for 24 to 72 h at 30° C. The first stage cultures were shaken at 250 rpm on a gyratory shaker during their incubation. All cultures were so shaken to provide appropriate aeration which is important for the growth of these organisms.
Generally, a 2.5 mL aliquot from the first stage culture just described was then added to 100 mL (or a 1.25 mL aliquot to 50 mL) of rich medium such as SFM, YM, or YMT contained in a 500 mL Erlenmeyer flask. Cultures containing 500 mL of a bacterial suspension were grown in a 2L flask in some experiments. Prior to sterilization, the pH of the medium was adjusted to between pH 6.0 and pH 7.0. Thereafter, no effort was made to control or adjust the pH which in some cases increases to nearly 9.0. There was little difference in the yields of 14-hydroxycodeine whether the bacterial transformation occured in YM or YMT medium. Because increased yields of 14-hydroxycodeine without concomitant increased yields of norcodeine, were obtained in SFM, it is the preferred medium for carrying out the process.
The resulting culture was grown for 18-24 h on a gyratory shaker, then a solution of sterile codeine phosphate was added to a final concentration of 1mM (0.29 mg/mL). Other water-soluble salts of codeine such as codeine hydrochloride of codeine acetate can also be used. After the addition of the codeine salt, the resulting culture was incubated, with constant shaking, for up to 30 days. The temperature of incubation is not critical but it should generally be under about 32° C., preferably in the range of 25° to 30° C. Samples (10 mL) were withdrawn at varying intervals and analyzed for 14-hydroxycodeine and norcodeine as described below.
DETECTION OF CODEINE, 14-HYDROXYCODEINE AND NORCODEINE
1. Analysis by gas chromatography (GC):
Culture samples (10 mL) were centrifuged at 8,000 x g and resulting supernatant fluids were brought to a pH of 9.5, and twice extracted with an equal volume of a 2:1 mixture of methylene chloride/ethyl alcohol. The resulting organic phase was separated from the water and evaporated to dryness. The dry crude residue was incubated at 80° C. for 30 minutes with 250 μL of N-methyl-N-trimethylsilyl trifluoroacetamide (MSTFA) to convert codeine and its transformation products to trimethylsilyl derivatives. The resulting products (0.5μL) were then injected onto a 10 meter, Series 530μ, 50% phenylmethyl silicone column produced by Hewlett-Packard. The temperature of the column was maintained at 150° C. for 10 minutes, and then the temperature was increased 10° C. per minute until it reached 235° C. where it was kept for an additional 8 minutes. Injector and detector temperatures were 265° C. and 300° C., respectively. Helium, to act as the carrier, was supplied at 10 mL per minute. The amount of the various products was determined by comparing the retention times on the column and the areas of the peaks with those of known amounts of known standard compounds.
2. Analysis by high pressure liquid chromatography (HPLC):
The culture samples (10 mL) were centrifuged at 8,000 x g and samples of the resulting supernatant fluids (25 μL) were injected onto a 4.6 mm by 25 cm Zorbax™ Sil column, manufactured by E. I. Du Pont De Nemours and Co. (Inc.), at 40° C. using a mixture of 0.13 N NH 4 OH/MeOH (65%) and 0.13 N NH 4 OH/H 2 O (35%) as the mobile phase. Detection of compounds was by ultraviolet absorbance. The compounds were quantitated by comparing the areas of the peaks with those resulting from the use of known amounts of known standard compounds.
EXAMPLE 1
An inoculum (1.25 mL) of Streptomyces griseus NRRL B8090 from a first stage culture was added to 50 mL of SFM in a 250 mL Erlenmeyer flask. The culture was incubated at 30° C. with shaking at 250 rpm. Twenty two and one-half hours later, 0.2 mL of a 10% solution of codeine phosphate was added to the culture. The cultures were further incubated at 30° C. with shaking at 250 rpm until 10 mL samples were removed 11 and 18 days later. The samples were analyzed by gas chromatography as described above to determine the quantities of codeine remaining and the amounts of 14-hydroxycodeine and norcodeine. The concentrations of 14-hydroxycodeine in the medium of the culture 10 and 17 days after the addition of codeine were 175 μM and 306 μM, respectively. The concentrations of norcodeine in the culture at the two time intervals were 25.9 μM and 52.2 μM, respectively.
EXAMPLE 2
This experiment was done essentially the same as Example 1 except the bacteria used were Streptomyces griseus ATCC 10137. The concentrations of 14-hydroxycodeine in the medium of the culture 10 and 17 days after the addition of codeine were 44.4 μM and 105 μM, respectively. The concentrations of norcodeine in the culture at the two time intervals were 41 μM and 139 μM, respectively.
EXAMPLES 3-10
A single experiment provides examples 3-10. The experiment was done essentially the same as Example 1 except that each culture contained different bacteria. Also, the samples removed for analysis were removed 14 days after the codeine was added in Examples 3-7 and 15 days after the codeine was added in Examples 8-10. The concentrations of 14-hydroxycodeine and norcodeine are given below.
______________________________________ Concentration, μM 14-hydroxy-Example Organism codeine norcodeine______________________________________3 S. griseus ATCC 23337 209 <54 S. griseolus ATCC 3325 148 <55 S. species WH110 12 256 S. griseolus ATCC 11796 22 267 S. griseus ATCC 13968 75 588 S. griseus ATCC 21897 55 579 S. lincolnensis ATCC 25466 118 2910 S. punipalus NRRL 3529 142 6______________________________________
EXAMPLE 11
This experiment was designed to determine whether yeast malt-extract plus L-tyrosine medium or soybean flour medium would support the best yield of 14-hydroxycodeine from the transformation of codeine. The experiment was done essentially as in Example 1 except that flasks containing SFM and YMT media were each inoculated with either S. griseus NRRL B8090 or S. griseus ATCC 10137. The concentrations of 14-hydroxycodeine and norcodeine in the cultures were determined 17 days after codeine was added to the cultures. Results:
______________________________________ Concentration (μM)Organism Medium 14-hydroxycodeine Norcodeine______________________________________NRRL B8090 SFM 306 52.2NRRL B8090 YMT 92.1 30.7ATCC 10137 SFM 105 139.7ATCC 10137 YMT 79.5 62.3______________________________________
The results show that S. griseus NRRL B8090 produced 3.3 times more 14-hydroxycodeine in SFM medium than in YMT medium and S. griseus ATCC 10137 produced 1.3 times more 14-hydroxycodeine in SFM medium that in YMT medium.
EXAMPLE 12
The experiments of this example were done essentially as that of Example 11. They differ prmarily in that YM medium was also included and the samples were collected 14 days after codeine was added to the cultures. Results:
______________________________________ Concentration (μM)Organism Medium 14-hydroxycodeine Norcodeine______________________________________NRRL B8090 YM 90 10NRRL B8090 YMT 80 20NRRL B8090 SFM 220 18ATCC 10137 YM 40 70ATCC 10137 YMT 70 30ATCC 10137 SFM 120 20______________________________________
The results show that S. griseus NRRL B8090 produced more 14-hydroxycodeine than S. griseus ATCC 10137, that more 14-hydroxycodeine was produced in Soybean flour medium (SFM) and that the increased yield of 14-hydroxycodeine was obtained without a concomitant significant increase in norcodeine.
EXAMPLE 13
This experiment was designed to determine the optimum time to incubate the bacterial culture containing codeine. An inoculum consisting of 2.5 mL of a a first stage culture of S. griseus NRRL B8090 was added to 500 mL of SFM medium. The culture was grown overnight at 30° C. on a gyratory shaker. The next morning, a sufficient amount of a solution of codeine phosphate was added to bring the concentration of codeine in the culture to 1 mM. The culture was incubated further as before. Samples (10 mL) were removed each day for the first week and every 2 to 4 days thereafter until the 29th day. The samples were analyzed for their content of codeine, 14-hydroxycodeine and norcodeine.
Results:
The concentration of codeine decreased from day one throughout the period of culture, reaching a final concentration of 125 μM. The product, 14-hydroxycodeine, was first detected on the fifth day of culture. The concentration increased continually becoming nearly maximal on day 18 at a concentration of 217 μM (maximal concentration was 220 μM on day 21). The concentration remained essentially constant thereafter until the end of the experiment on day 30. Norcodeine was detected after the first day of culture. It reached its maximum concentration of 28 μM on day 5 and thereafter decreased until there was none in the culture at day 25.
The optimum time for the production of 14-hydroxycodeine in this culture was 18-20 days when maximal 14-hydroxycodeine had been produced but not all the codeine had been metabolized thus making it recoverable. These results are shown in the drawing.
EXAMPLE 14
This experiment was essentially the same as Example 13 except that the beginning concentration of codeine added to the culture was 2mM instead of 1 mM.
Results:
The product 14-hydroxycodeine was first detected on day 3 after the addition of codeine. It reached its maximum concentration of about 260 μM after 12 days of culture. As in the previous experiment the concentration of 14-hydroxycodeine stayed nearly constant thereafter while the concentration of codeine in the medium continued to decrease. Thus, the optimum time to get the maximum production of 14-hydroxycodeine and preserve the untransformed codeine would be after a 12 day culture period. As in Example 13, norcodeine production began immediately, reached a maximal concentration of about 57 μM on day 7 and decreased to undetectable levels by day 25.
EXAMPLE 15
This experiment was done to determine the optimum concentration of codeine to use. The bacteria used were S. griseus ATCC 10137 and the medium was either YM or YMT. Each culture contained 10 mL of medium that had been inoculated with 0.25 mL of a first stage culture. The resulting cultures were incubated overnight at 30° C. with continuous shaking at 250 rpm. Codeine as a solution of codeine phosphate was added to each culture so that one culture in each medium contained 1.25 mM, 2.5 mM, 5 mM, and 12.6 mM codeine. The cultures were incubated further, with shaking, for 7 days. Cell viability and the concentration of 14-hydroxycodeine were determined.
Results:
The number of viable cells dropped dramatically in those cultures containing codeine at a concentration of 12.6 mM. There was a greater number of viable cells in the cultures in YMT medium. Cells grown in YM medium produced more 14-hydroxycodeine when the starting concentration of codeine was 2.5 mM and none when the codeine concentration was 12.6 mM. Cells grown in YMT medium produced more 14-hydroxycodeine when the starting codeine concentration was 1.25 mM, less when the starting concentration of codeine was 2.5 mM and 5.0 mM, and none when the starting concentration of codeine was 12.6 mM. This is shown below.
______________________________________ Starting codeine 14-hydroxycodeineMedium concentration (mM) concentration (μM)______________________________________YM 1.2 24 2.5 46 5.0 32 12.6 0YMT 1.2 62 2.5 21 5.0 23 12.5 0______________________________________
|
A microbial process for converting codeine to 14-hydroxycodeine is provided. This process comprises aerobically culturing codeine with bacteria of the genus Streptomyces for at least about 3 days in a rich medium such as soybean flour medium.
| 8
|
This is a division of application Ser. No. 803,777 filed June 6, 1977, now U.S. Pat. No. 4,181,760.
BACKGROUND OF THE INVENTION
Electroless or autocatalytic plating of dielectric substrates finds wide-spread utility in the preparation of such diverse articles as printed circuits, automotive trim, mirrors, electronic devices, etc.
In the normal commercial electroless plating process, the dielectric substrate, which has been preferably etched by physical or chemical means to improve metal adhesion, is sensitized by exposure to a solution of stannous ions, e.g., a stannous chloride solution, and then activated by exposure to a solution of palladium ions, e.g., a palladium chloride solution. This activation is effected by reduction of the palladium ions to the zero valence state by the stannous ions to form palladium metal sites or by the formation of a tin/palladium complex on the surface of the dielectric substrate.
Thereafter, the activated substrate is plated by exposure to an electroless plating bath containing ions of the metal to be plated and a reducing agent capable of reducing (heterogeneously) the valence state of the plating ions present in the bulk solution to the metallic state. In conventional processes, copper is plated using an electroless plating bath comprised of copper ions and formaldehyde as a reducing agent. In the plating of nickel or cobalt, the reducing agent commonly used is sodium hypophosphite.
More recently, processes have been developed for electroless plating without the necessity of using palladium or other precious metals. For example, in U.S. Pat. Nos. 3,772,056 and 3,772,078, non-metallic substrates are coated with a solution containing non-precious metal ions, i.e., ions of copper, nickel, cobalt or iron, and dried to form an adherent coating of the metal ions. Thereafter, the metal ions are reduced to the metallic state and the substrate is plated with a compatible electroless plating bath.
In U.S. Pat. No. 3,993,491 another procedure for effecting electroless plating of non-metallic substrates without the necessity of using palladium or any other precious metal ions is described. In the processes described therein, a non-metallic substrate is contacted with stannous and copper ions to form a stannous-cuprous complex on the surface of the substrate. The copper ions are then reduced to their metallic state using a suitable reducing agent.
Still another procedure is described in U.S. Pat. No. 3,993,799. In the process described therein, hydrous oxide colloids of metal or metal ions are coated on the surface of a non-metallic substrate. The substrate is then rinsed and immersed in a solution containing a reducing agent capable of reducing the metal ions to the metallic state (or reducing the outer surface).
While significant cost savings are realized by coating the substrates with non-precious metal ions, as exemplified by the above disclosures, instead of with the more expensive palladium or other precius metal ions, care must be exercised in the selection of the electroless plating bath used with such systems. Specifically, conventional hypophosphite baths are not effective in the plating of nickel or cobalt onto the surface of substrates prepared using non-precious metals e.g., copper or silver, in a commercially suitable manner. Instead, it is necessary in the plating of nickel and cobalt to use an electroless plating bath containing a stronger reducing agent such as a boron reducing agent, e.g., an amine-borane, such electroless plating baths being disclosed, for example, in U.S. Pat. No. 3,338,726, or a borohydride, as shown in U.S. Pat. Nos. 2,461,661 and 3,045,334. Such reducing agents, because of their relatively higher cost, diminish the commercial savings to be realized in the use of such procedures. Also, in using the preceding non-precious metal systems, at times a lower site density is realized thus reducing the speed and effectiveness of plating onto the prepared substrates.
Procedures permitting the utilization of non-precious metal activated substrates while eliminating or minimizing the aforesaid disadvantages and permitting the utilization of conventional, commercially available electroless plating baths would be highly desirable.
It is also well documented in the art that there are a wide variety of metals and alloys which are non-catalytic for initiation of conventional electroless plating. Typical materials which are non-catalytic include copper, gold, silver, chromium containing stainless steels, Kovar, moly, manganese, aluminum and its alloys and others. In the prior art, exotic procedures have been adapted to provide such non-catalytic materials catalytic. Typical procedures well known are activation with palladium, zincating method, impressing of a galvanic potential and others. It is well documented that such procedures are tedious and costly and it would be highly desirable to eliminate them by a simple treatment which potentially would be universal to all noncatalytic materials (metals and alloys). Surprisingly, I found that the composition disclosed may also be used effectively upon these non-catalytic materials and thereby render the surface of such material platable in conventional electroless plating baths. In an attempt to overcome such tedious procedures, a recent effort is described in U.S. 4,002,778 which is included herein by reference. However, there is still room for improvement with regard to the number of steps and the economy of the process used.
SUMMARY OF THE INVENTION
It is the principal object of the present invention to produce a metallized product of a non-catalytic metal or alloy prepared by the steps of
(a) contacting the substrate to be coated with a promoter composition which comprises a reducing agent and metal ions, said reducing agent being capable of chemically reacting with said substrate and the metal ions within the composition and wherein said metal ions are selected from the group of nickel, cobalt, and iron and wherein the relative concentration of the reducing agent to the metal ions is so adjusted as to permit the initial chemical interaction of the reducing agent with said substrate and then the heterogeneous reduction of some of the metal ions present in said composition, and then
(b) contacting the treated substrate with a conventional electroless plating bath comprising hypophosphite and thereby depositing a metallic layer.
DETAILED DESCRIPTION OF THE INVENTION
The term "priming" as used in the present description means the formation of a coating of non-precious metal ions (or metals or alloys) and including silver and other non-catalytic metals onto the surface of a non-metallic (dielectric) substrate or metallic substrates. The priming step does not per se form a part of the present invention. Priming may be effected by one of a number of techniques including the procedures described in the above-mentioned patents. Priming may also be effected by vapor deposition, spraying, printing, dipping, etc., or the formation of a metal in the metallic state on the substrate surface followed by permitting or causing the surface of the metal to oxidize. For certain purposes, priming may be on selected regions of the substrate, thereby resulting in selective plating.
Because of their particular effectiveness and commercial significance, the non-metallic substrates will normally be primed with copper ions, either cuprous or cupric, and the following description will be primarily directed to the plating of copper and silver primed substrates as well as non-catalytic metals and alloys. It is to be understood, however, that the present invention is broadly directed to the plating of non-metallic, metallic or semiconductor substrates primed with other metals or their ions, e.g., nickel, cobalt, iron, tin, mercury, silver, etc.
The term "developing" (or promoting) as used herein means the reduction of metal ions coated on the substrate to the metallic or zero valence state with a chemical reducing agent capable of effecting such reduction, or the initial interaction of the reducing agent with the non-catalytic metal (or alloy) previously deposited onto the substrate, or which is part of the substrate with the sequential deposition of metal (e.g., nickel, cobalt, iron) which is derived from the bulk solution of the developing medium. Accordingly, the developing medium will be referred to as "developer" or "promoter". It is recognized that the interaction of the promoter is a surface reaction; the properties or the nature of the bulk substrates is of no major concern. Accordingly, the concentration of the reducing agent must be so adjusted relative to the metal ions in the bulk solution as to insure the preferred sequence of chemical reactions. It is also noted that the promoter composition may also include other additives from pH adjusters to complexing agents which should be obvious to one skilled in the art. It is recognized that proper selection of complexing (or chelating) agents is important whereby the metals ions are complexed but still available for the heterogeneous reduction at moderate conditions (e.g., temperature and/or reducing agent concentration).
The term "non-catalytic metal" as used in the present invention refers to a wide variety of materials (metals or alloys) which are not catalytic and hence would not initiate conventional electroless plating. Typical materials may include, however are not limited to, copper, gold, silver, chromium containing steel, stainless steels, steel Kover, moly, aluminum and its alloys, zinc, and others.
The process and systems of the present inention are applicable to the metallic plating of a wide variety of substrates (semiconductors, dielectrics, and metallic). It is noted that some of the objectives set forth in this invention are met in a recent patent, U.S. Pat. No. 3,993,801 which is included herein by reference.
In general, the process of the present invention comprises the following steps:
(A) Priming of the substrate, which has preferably first been etched, with a metal alloy or metal ions, preferably copper and silver or non-catalytic metals,
(B) Immersing said substrate in a promoter composition containing metal ions selected from nickel, cobalt, iron and copper ions and mixtures thereof, and a reducing agent capable of reducing or interacting first with the metal or metal ions on the substrate and then heterogeneously reducing the ions in the promoter bulk solution to the metallic state, and
(C) Electrolessly plating said substrate by immersing said substrate in an electroless plating bath containing ions of the metal to be plated and a reducing agent capable of reducing heterogeneously the valence state of the ions in the electroless plating bath to the metallic state.
It is recognized that when dealing with bulk metals or alloys, the priming step does not exist per se. More specifically, in the plating of nickel or cobalt onto a substrate primed with silver or other non-catalytic metals, the process comprises the following steps:
(A) Immersing the primed substrate in a promoter solution containing ions of nickel or cobalt and a reducing agent capable of reducing the silver ion or interacting with metallic silver on said substrate and said nickel or cobalt ions to the metallic state; and
(B) Immersing the developed substrate into an electroless plating bath containing nickel or cobalt ions and a reducing agent capable of reducing said nickel or cobalt ions to their metallic state, e.g., a hypophosphite.
As noted previously, it is another specific object of the present invention to provide improved electroless copper plating onto copper primed substrates. This objective may be accomplished by developing the copper primed substrate with the developer solution described above for the plating of nickel or cobalt, or a similar bath containing copper ions, followed by immersion of the developed substrate in a conventional electroless copper-formaldehyde bath.
It is believed that improved copper plating is achieved using the above developer solutions through intensification of the sites on the substrate due to plating of copper, nickel or cobalt from the developer solution onto the substrate. Such intensification appears to be effected by the deposition onto the substrate of a thin layer, i.e., less than 1000 A in thickness on the surface may be sufficient; however, for certain applications one may extend to a greater thickness.
Suitable reducing agents used in the promoter solutions of the present invention may be any chemical reducing agent capable of reducing the ions on the substrate (or chemically interacting with the metal present on the surface) and also in the developer solution to the metallic state. In the chemical interaction, generally hydrogen gas is formed through the presence of a reactive intermediate adsorbed on the surface. While I do not wish to be bound by theory, the adsorbed intermediate may be chemisorbed nascent hydrogen or a hydride ion, both of which are short lived. Exemplary of such reducing agents are amine-boranes, borohydrides, hydrazine and its derivatives, N-alkyl-borazones, N-alkyl-borazoles, borozenes, borazines, and mixtures thereof. Particular reducing agents include dimethylamine borane, diethylamine borane, and the alkali metal and alkaline earth metal borohydrides, such as potassium and sodium borohydrides.
The following are a few publications describing the use of miscellaneous reducing agents (e.g., hydrazine) which have been reported capable of both copper and nickel plating.
P. Fintschenko et al, Metal Finishing, January (1970).
D. J. Levy, Proc. Electroplaters Soc., 50, p. 29 (1963).
D. J. Levy, Electrochem. Tech., 1, No. 1-2, p. 38 (1963).
J. W. Dini et al, Plating, 54, p. 385 (1967).
While not wanting to be held to any particular theory, it is believed that treatment of the primed substrate with the promoter solution results in the reducing agent present in the developer solution first reducing the copper ions (or interacting with the metallic copper) present on the surface of the substrate to their metallic state (or an activated state), the reduction reaction being indicated by the formation of a brown color on the substrate. Thereafter, additional reducing agent in the developer solution heterogeneously reduces the valence state of the ions in the bulk developer solution to the metallic state causing plating of the metal onto the substrate. In the case of nickel, this latter step is indicated by the formation of a greyish color on the substrate. Accordingly, sufficient reducing agent should be present in the developer solution to insure the sequential reaction with the primed surface and thereafter heterogeneously reduce the ions in the developer solution. Thus for increased probability, a molar ratio of reducing agent to metal ions in the developer solution should exceed 1:1, and preferably should be at least 2:1. Ratios greater than about 15:1, while workable, are of little practical value and serve to increase the cost of the process. The molar concentration of the reducing agent will normally be within the range of from about 0.015 M to about 0.2 M; and the molar concentration of the metal ions will normally be within the range of from about 0.003 M to about 0.1 M. Surprisingly, it is noted that the concentration of reducing agents used in electroless plating baths (boron type), as referred in the prior art, all normally range from about 0.015 to about 0.2 m/l, while the metal ion concentration will range from about 0.02 to about 0.5 m/l. The molar ratio of reducing agent to metal ions, thus, is less than 1:1, and normally between 0.75 and 0.4. Such baths are taught, for example, in U.S. Pat. No. 3,338,726 as typical compositional make-up which are effective for electroless metal build-up.
Conventional electroless plating baths suitably used in plating in accordance with the present invention are comprised of ions of the metal to be plated, a complexing agent, and a reducing agent. In nickel or cobalt baths, the reducing agent commonly employed is a hypophosphite reducing agent, such as sodium hypophosphite; in copper baths, the reducing agent commonly employed is formaldehyde or other electroless (chemical) plating baths which are not compatible with the substrates to be plated.
In the preparation of such baths, the metal ions are suitably derived from salts of the metal, e.g., the chloride or sulfate salts. Suitable complexing agents are well known in the art and include ethylenediamene tetraacetate, citrate and ammonia.
The following examples are presented as illustrative of the present invention and not in limitation thereof. In the examples where nickel ions are used in the developer or plating solutions, it will be apparent to one skilled in the art that cobalt ions, because of their similar properties, may be substituted.
EXAMPLE I
In this example as well as the following examples, the following procedure was employed:
1. Immerse ABS substrates, previously etched with a CrO 3 /H 2 SO 4 solution, into the described primer solution for several minutes;
2. Rinse;
3. Immerse primed substrate into the described developer solution;
4. Rinse (optional); and
5. Immerse developed substrate into described electroless plating bath.
In the present example, a primer solution having the following composition was used at room temperature:
SnCl 2 2H 2 O: 81 g/l
CuCl: 6 g/l
HCl (conc.): 45 cc/l
Phenol: 40 g/l
Following immersion in the above primer solution, the primed substrates were rinsed and immersed in the following developer (promoter) solution:
Dimethylamine borane DMAB): 3 g/l
NiSO 4 .6H 2 O: 2.5 g/l
Citric acid.H 2 O: 3.6 g/l
NH 4 OH to pH: 8.8
Temperature: 36° C.
It was observed that within 2-3 minutes the surface becomes brown in color, and within 3-5 minutes a complete intensification took place as shown by a grey color.
Nickel plating was achieved by immersion of the developed substrate in the following electroless nickel-hypophosphite bath:
Bath 1
NiSO 4 .6H 2 O: 12.5 g/l
Citric acid.H 2 O: 18 g/l
NH 4 OH to pH: 8.9
NaH 2 PO 2 .H 2 O: 18 g/l
Temperature: 25° C.
As aforementioned, improved copper plating can also be achieved using the present improved developer solutions due to intensified site development. Thus, uniform plating of copper was achieved by immersion of a substrate developed in the foregoing manner into a conventional electroless copperformaldehyde bath having the following composition:
Bath 2
CuSO 4 .5H 2 O: 10 g/l
KNaC 3 H 4 O 6 .4H 2 O: 16 g/l (potassium sodium tartrate):
NaOH: 16 g/l
H 2 CO (37%): 8 g/l
EXAMPLE II
Electroless plating of nickel and copper was obtained using the procedure, primer solution and electroless plating baths of Example I with the following developer solution:
DMAB: 3 g/l
CoSO 4 .7H 2 O: 1.25 g/l
Sodium citrate.2H 2 O: 2.5 g/l
NH 4 OH to pH: 8.8
Temperature: 36° C.
EXAMPLE III
Electroless plating of nickel and copper was obtained using the procedure, primer solution and electroless plating baths of Example I with the following developer solution:
DMAB: 3 g/l
CoSO 4 .7H 2 O: 1.25 g/l
Sodium citrate.2H 2 O: 2.5 g/l
CuSO 4 .5H 2 O: 0.072 g/l
NH 4 OH to pH: 8.8
Temperature: 36° C.
It should be noted that this composition is more reactive in comparison to the composition of Example II and thus lowering of the reactivity is recommended. Moreover, it should be obvious to those skilled in the art of plating that the catalytic surface resulting at the conclusion of the development stage consists of both cobalt and copper.
EXAMPLE IV
Electroless plating of nickel and copper was obtained using the procedure, primer solution and electroless plating baths of Example I with the following developer solution:
DMAB: 3 g/l
Nickel sulfamate: 0.8 g/l (Ni)
NH 4 OH to pH: 8
Temperature: 38° C.
Good intensified development took place within 5 minutes. Additional Tergitol (TMN) surfactant seemed to improve the overall uniformity.
EXAMPLE V
In this example, priming of the ABS substrate was achieved using as the primed solution a hydrous oxide colloid of copper prepared by adding 400 ml of 0.025 molar NH 4 OH dropwise with stirring to 1600 ml of 0.0125 molar copper acetate.
ABS substrates primed with the above colloidal solution were developed using the following developer solution:
DMAB: 4 g/l
Nickel sulfamate: 1.6 g/l (Ni)
NaOH to pH: 6.2
Temperature: 44° C.
Using the electroless nickel bath of Example I, a complete intensified developed surface was obtained within 5 minutes of immersion, and good initiation in the electroless bath was noted. It should be noted that using a modified developer formulation similar to Example No. 1 was poor, probably due to the presence of ammonia. Based upon this example and procedure, it should be obvious that hydrous oxide colloids of cobalt and nickel may be used as well as combinations thereof.
EXAMPLE VI
DMAB: 1.5 g/l
NiSO 4 .6H 2 O: 1.25 g/l
Citric acid.H 2 O: 1.8 g/l
NH 4 OH to pH: 7.8
Temperature: 37° C.
When substituting the above solution after a partial degassing for the developer solution of Example V, it was noted that development took place within 2 minutes while complete intensification took place in about 8 minutes. In this example, no agitation or surfactant was included. The intensified developed substrate was directly immersed into the electroless nickel bath of Example I with good immediate initiation noted. Dilution (×2) of the above modified developer formulation under the same conditions did result in intensified development, however with a lower speed.
EXAMPLE VII
Electroless plating of nickel was obtained using the procedure, primer solution and electroless nickel plating bath of Example I with the following developer solution:
NiCl 2 .6H 2 O: 3 g/l
Ethylene diamine: 5 g/l
Potassium borohydride: 1 g/l
pH: 9.9
Temperature: 38° C.
Standard development was noted within two to three minutes of immersion, while complete intensification was observed only after about twelve minutes of immersion. The latter could be foreshortened by further adjusting developer reactivity and probably by lowering or eliminating the ethylenediamene concentration. Following the intensified development good initiation in the electroless bath No. 1 took place. To overcome some of the stability problems associated with borohydrides, the use of salts of cyano-borohydrides is recommended. The latter show good stability over a wide pH range.
EXAMPLE VIII
As stated previously, one of the novel features of this invention is the fact that development and intensification take place in the same medium in a preferred sequence of events. This feature is accomplished to a large extent by the relative concentration make-up of the developer solution. To better illustrate this point the following results are provided.
______________________________________ Observed timing (minutes) to:DMAB.sup.(a) /NiSO.sub.4 . Development Intensified6H.sub.2 O(g/g) (brown color DevelopmentNo. in modified solution formation) (grey color formation)______________________________________1 3/12.5 .sup.(b) none after 7 min.2 3/6.25 .sup.(b) 40% only after 7 min.3 3/3.12 21/2 44 3/1.6 21/2 4______________________________________ .sup.(a) All developer solutions were operated at 39° C. and were also composed of citric acid H.sub.2 O × 1.44 the weight of nickel sulfate hexahydrate. Ammonium hydroxide was used to maintain a pH of 8.7. .sup.(b) The observation of a brown color was nonreproducible and in case in which a brown color was formed, the intensified development was sluggish.
EXAMPLE IX
A ceramic substrate coated with silver was used; the silver was derived from a printable ink composition. After activation in a 20% hydrochloric acid, the substrate was effectively treated in the developer of Example I and then in electroless nickel-phosphorus formulation. It is recognized that in using surface primed with silver, it is advantageous to include within the developer composition a silver complexing agent. Such inclusion will extend the life of the developer composition, hence making the process more economical.
I have also found that due to the non-noble (precious) characteristic of silver it may be required to treat the silver surface prior to the developer composition as to dissolve any oxide layer.
EXAMPLE X
Cleaned non-catalytic materials such as moly, chromium, copper, chromium containing steel, and an alloy of aluminum (7075 T6, 6061 T6), were contacted for 1 to 2 minutes in a composition of Example I at temperature range 60° to 70° C. After this treatment, the materials were immersed in a conventional electroless nickel using hypophosphite as the reducing agent. It was noted that instantaneous plating was started. The plated parts surprisingly have also shown good adhesion before and after heat treatment.
|
A process, article produced therefrom, and compositions are described for the reception of electroless plating onto a substrate of a non-catalytic metal or non-catalytic alloy. The process comprises contacting the surface of the non-catalytic substrate with a promotor composition containing ions selected from the group of nickel, cobalt, iron, and mixtures thereof and a suitable reducing agent, and thereafter contacting the treated surface with an electroless plating bath comprising hypophosphite for metallic build-up.
| 8
|
BACKGROUND OF THE INVENTION
a) Field of the Invention
The present invention relates to an improved process for preparing a nanocrystalline powder of an alloy made of at least two metals.
More particularly, it relates to an improved process wherein the nanocrystalline powder is obtained by subjecting a mixture of metal powders to an intensive mechanical grinding carried out in a high energy, ball milling machine or any similar piece of equipment.
The term "nanocrystalline" as used herein designates any kind of powder consisting of crystallites having a grain size lower than 100 nm.
b) Brief Description of the Prior Art
The preparation of alloys by intensive metal grinding (or milling) of a mixture of metal powders is a well known technique.
Recently, this technique which is also called "mechanical alloying", has been found particularly efficient for the preparation of hydrogen absorbing alloys like FeTi, LaNi 5 and Mg 2 Ni, which are in the form of crystallites and can form hydrides reversibly and thus be used for storing hydrogen.
It has also been found that hydrogen absorbing alloys of very high efficiency are obtained if the mechanical grinding is carried out in such a manner as to reduce the size of the crystallites that are formed to a few nanometers. Indeed, with such nanocrystalline alloys, it becomes possible to store hydrogen very rapidly and without requiring long activation treatment as is necessary when use is made of the same alloys in a conventional polycrystalline form.
In EP-A-671,357 (corresponding to U.S. patent application Ser. No. 08/387,457 filed on Feb. 13, 1995), there is disclosed a process for the preparation of a nanocrystalline powder of an alloy of the formula Mg 2-x , Ni 1+x wherein x ranges between -0.3 and +0.3, which consists in grinding at ambient temperature and atmospheric pressure under an inert atmosphere, a Mg powder with a Ni powder in such amounts as to obtain the requested alloy. In order to obtain the requested crystallites of the formula Mg 2-x N 1+x and to reduce their grain size to less than 100 nm, it is compulsory to grind the metal powders for at least 50 hours (in the diffraction spectra shown in FIG. 3 of this U.S. patent application Ser. No. 08/387,457 one can see that the requested alloy starts being formed after 26 hours and its full synthesis and the reduction of its crystalline size to less than 30 nm are completed after 66 hours).
In international laid-open patent application No. WO 96/23906 (corresponding to U.S. patent application Ser. No. 08/382,776 filed on Feb. 2, 1996), there is disclosed a process for the preparation of a material of the formula:
(M.sub.1-x A.sub.x)D.sub.y
wherein:
M is Mg, Be or a combination thereof;
A is at least one element selected from the group consisting of Li, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Al, Y, Zr, Nb, Mo, In, Sn, IO, Si, B, C and F (preferably Zr, Ti and Ni);
D is a hydrogen dissociation catalyst selected from the group consisting of Fe, Co, Ni, Ru, Rh, Pd, Ir and Pt (preferably Pd);
x is a number (atomic fraction) ranging from 0 to 0.3; and
y is a number (atomic fraction) ranging from 0 to 0.15 (preferably from 0 to 0.02).
This material is of a very light-weight and is capable of reversibly storing hydrogen with very good kinetics. It consists of a powder of particles of the formula M 1-x A x having an average size ranging from 0.1 to 100 μm. Each particle may consist of nanocrystalline grains having an average size of 3 to 100 nm. Alternatively, each particle may have a nano-layered structure with a layer spacing of 3 to 100 nm. Some of the particles have clusters of at least one of the metals D attached thereof, each cluster having an average size ranging from 2 to 200 nm.
The process used for preparing this material basically consists in intensely grinding a powder of the metal M until the grain size of the crystallites reaches the requested value, or intensely grinding a mixture of a powder of metal M with a powder of the other metal A in a steel or tungsten carbide crucible of a high energy ball mill. Once again, such grinding is carried out at ambient temperature under an inert atmosphere at atmospheric pressure. It must also be carried out for an extensive period of time so as to obtain the requested particles of formula M 1-x A x and to reduce their grain size to the requested value. Once this grinding step is completed, a given amount of the hydrogen dissociation catalyst D can be added to the particles and the resulting mixture is subjected to an additional grinding step to apply clusters of the catalyst D onto the particles M 1-x A x .
In the article of L. ZALUSKI et al entitled "Effects of relaxation on hydrogen absorption in Fe--Ti produced by ball-milling", Journal of Alloys and Compounds, 227 (1995) 53-57, there is disclosed a process for the preparation of a nanocrystalline powder of a FeTi alloy, which consists of grinding at ambient temperature under an inert atmosphere a mixture of elemental Fe and Ti powders in a high-energy ball milling machine.
This article also discloses that a large amount of energy can be stored in the nanocrystalline FeTi fabricated by high energy ball-milling, as a result of mechanical deformation. Such leads to a high concentration of structural defects (high level of internal strain) and to chemical disorders.
This article further discloses that after having been prepared, the alloy can be subjected to a relaxation treatment consists of annealing the alloy at a temperature of 400° C. in order to reduce its internal strain to at least 40% of the initial value. Surprisingly, such annealing does not change the size of the crystallines. Moreover, annealing gives rise to the appearance of a well-defined plateau in the pressure-composition isotherm of hydrogen adsorption of the alloy at room temperature.
In all cases, the preparation of nanocrystalline alloys by mechanical alloying calls for the mechanical grinding to be carried out for a substantial amount of time, which is generally higher than 50 hours and can be as high as 120 hours.
SUMMARY OF THE INVENTION
It has now been discovered that even when the intensive mechanical grinding is carried out at an elevated temperature, one may still obtain a nanocrystalline alloy.
It has also been discovered that, in such a case, the amount of time required to prepare nanocrystalline alloys by intensive mechanical grinding can substantially be reduced. As a matter of fact, when the grinding is carried out at an elevated temperature ranging from about 100° C. to about 400° C. instead of being carried out at ambient temperature, one may prepare a nanocrystalline alloy powder within a few hours instead of a few ten hours.
Of course, such a reduction in time results in a reduction in the preparation cost, as the amount of energy required for simultaneously grinding and heating the powders for a short period of time is usually smaller than the amount of energy required for operating the ball-milling machine at ambient temperature for a very long period of time.
It has further been discovered that when the grinding step is carried out at an elevated temperature, some structural defects (holes, dislocations, internal strain) are "automatically" avoided, thereby making it possible to obtain nanocrystalline powders of hydrogen adsorbing alloys like Mg 2 Ni or FeTi, without having to subject the same to a subsequent annealing.
As a matter of fact, it has been found that when the grinding step is carried out at 100° to 400° C., interdiffusion of the elements of the powder mixture processed within the crucible of the ball milling machine is improved, thereby resulting in a substantial reduction of time in the preparation process, and in the obtention of alloys having less-intrinsic defects.
The preparation of a nanocrystalline alloy by intensive mechanical grinding of a mixture of metal powders at elevated temperature should not be confused with the conventional induction melting processes used for preparing alloys, or with the conventional sintering process well known in the metallurgical art. Thus, by way of example, Li J. et al in Advanced Materials, vol. 5, No. 7/8, July 1993, pp. 554-555, disclose an induction melting process consisting in heating constituent metals to 850° C.-900° C. under an inert atmosphere, cooling them to the room temperature and pulverizing them into particles of 25 to 100 mesh. This process and the range of operating temperatures are completely different from those mentioned hereinabove and the resulting alloy is not of nanocrystalline structure.
In the same article of Li et al, there is also disclosed a process for the production of a Mg 2 Ni alloy using a powder metallurgy technique, which comprising mixing Mg and Ni powder in appropriate proportions, shaping the mixed powders in an isobaric press, subjecting the shaped mixture to sintering at 300° to 600° C. for 1 to 10 hours in a tube furnace; and letting it cool to room temperature under argon. In this sintering process, there is no mechanical grinding and the particles of alloy that are obtained are not of nanocrystalline structure.
Thus, the present invention as claimed hereinafter is directed to an improved process for preparing a nanocrystalline powder of an alloy made of at least two metals, which process is the type comprising the step of subjecting to an intestive mechanical grinding a mixture of powders of these metals in such amounts as to obtain the requested alloy. As usual, such intensive metal grinding must be carried out under atmospheric pressure in an inert atmosphere and for a period of time sufficient to achieve formation of the crystallites and reduction of the grain size of the crystallites to the requested value.
In accordance with the invention, this process is improved in that the intensive mechanical grinding is carried out at an elevated temperature ranging from about 100° C. to about 400° C. and preferably from 150° C. to 300° C., whereby a substantial reduction of the above mentioned period of time is achieved.
The invention and its advantages will be better understood upon reading the following non-restrictive detailed description thereof, made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of the alloying process that takes place when a mixture of metal powders is subjected to intensive mechanical grinding at elevated temperature;
FIG. 2 is a representation of the X-ray diffraction spectra of a mixture of Mg and Ni in a mole ratio of 2:1, while the same was subjected to intensive mechanical grinding at room temperature, the spectra having been taken at intervals of 15, 60, 120 and 150 hours;
FIG. 3 is a curve showing the hydrogen absorbtion rate at 12 bars and 300° C. of a nanocrystalline Mg 2 Ni alloy prepared by intensive mechanical grinding for 150 hours at room temperature, after one absorption;
FIG. 4 is a representation of the X-ray diffraction spectrum of a mixture of Mg and Ni in a mode ratio of 2:1, taken after 5 hours of intensive mechanical grinding at about 290° C.;
FIG. 5 is a curve similar to the one of FIG. 3 showing the hydrogen absorption rate at 12 bars and 300° C. of a nanocrystalline Mg 2 Ni alloy prepared by intensive mechanical grinding for 8 hours at about 200° C., after three absorptions;
FIG. 6 is a curve similar to the one of FIG. 5, showing the hydrogen absorption rate at 12 bars and 200° C. of the same alloy after four absorption; and
FIG. 7 is a curve showing the pressure-composition isotherm at 300° C. of the alloy used for the tests reported in FIGS. 5 and 6.
DETAILED DESCRIPTION OF THE INVENTION
As aforesaid, the process according to the invention is intended to be used for preparing a nanocrystalline powder of an alloy made of at least two metals. By "nanocrystalline" powder, there is meant a powder consisting of crystallites having a grain size lower than 100 nm.
The process is of the "mechanical alloying" type and comprises the step of subjecting to an intensive mechanical grinding powders of different metals in such amounts as to obtain the requested alloy.
As is conventional, the intensive metal grinding is carried out at atmospheric pressure under an inert atmosphere for a period of time sufficient to achieve formation of the crystallites and reduction of the grain size of these crystallites to the requested value.
In accordance with the invention, the intensive mechanical grinding be carried out at an elevated temperature ranging from about 100° C. to about 400° C., instead of being carried out at ambient temperature. Such results in a substantial reduction of time in the preparation of the nanocrystalline alloy and in the obtention of alloys having much less intrinsic defects.
As can be understood, the higher is the temperature, the more expensive will be the process because of the heat energy cost. Thus, it is preferable that the process be carried out at a moderate temperature ranging from about 150° C. to about 300° C.
The intensive mechanical grinding can be carried out in a high-energy ball milling machine like those sold under the trademarks SPEX 8000, FRITCH and ZOZ.
If desired, up to 10% by weight of a lubricant can be added to the mixture of powders to be ground. Such lubricant may for example, consisting of carbon, boric nitride or Al 2 O 3 .
This improved process is particularly well adapted for the preparation of hydrogen absorbing Ni or Mg based alloys.
The Ni-based alloys may be:
a 1 ) bimetallic alloys made of Ni and one other metal selected from the group consisting of Be, Li, Mg and La; or
a 2 ) intermetallic alloys made of Ni, at least one other metal selected from the group consisting of Be, Li, Mg and La, and at least one further metal selected from the group of Al, Co, Cu, Fe, Pd, Zn, Ti, V, Cr, Mn, Zr, Nb and Ca.
The process according to the invention can also be used for preparing nanocrystalline alloys of Fe and Ti with possible addition of Mn, or bimetallic alloys of the formula:
(M.sub.1-x A.sub.x)
wherein:
M is Mg, Be or a combination thereof;
A is at least one element selected from the group consisting of Li, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Al, Y, Zr, Nb, Mo, In, Sn, O, Si, B, C and F; and
x is a number ranging from 0 to 0.3
If desired, when the intensive mechanical grinding has been completed and the requested alloy has been obtained in the form of crystallites having a grain size lower than 100 nm, a given amount of a powder of a hydrogen dissociation catalyst can be added to the crystallites and the resulting mixture can be subjected to an additional grinding so as to apply clusters of the hydrogen dissociation catalyst onto the crystallites. Such catalyst can be, for example, Pd, Pt, Ir or Rh.
As was already explained hereinabove, heating of the metal powder mixture while the same is subjected to intensive mechanical grinding has been found not to affect the nanocrystalline structure of the resulting alloys. It has also been found that this process substantially reduces the grinding time that is higher than 25 hours and more commonly ranging from 50 to 120 hours, down to less than 10 hours. It has further been found that this process substantially reduces the strain and internal defects of the alloys, thereby making them more efficient (well-defined plateau and higher storage capacity).
As is shown in FIG. 1, mechanical grinding of powders of different metals (shown in black and white) allows the formation of a layered structure. Simultaneous heating causes an interdiffusion of the metals (shown in dotted lines) and a substantial acceleration in the formation of the resulting alloy.
In order to shown the advantage and efficiency of the process according to the invention, comparative experiments were carried out, using Mg 2 Ni as illustrative alloy.
COMPARATIVE EXAMPLE
7 g of Mg and Ni in a mole ratio of 2:1 were subjected to an intensive mechanical grinding in a high energy ball milling machine SPEX® 8000, having a crucible of 60 ml. Use was made of three steel balls (2 of 7/16" and 1 of 9/16"). The grinding was carried out under a nitrogen atmosphere at ambient pressure and ambient temperature for up to 150 hours. The Mg 2 Ni crystallites that were so obtained had a grain size ranging from 10 to 15 nm.
As is shown from the X-ray diffraction spectra given as in FIG. 2, Mg 2 Ni was formed after 60 hours. After 120 hours, the alloy formation was completed.
FIG. 3 shows the hydrogen absorption rate of the Mg 2 Ni alloy that was so prepared, at 12 bars (about 170 PSI) and 300° C.
EXAMPLE 1
Like in the comparative example disclosed hereinabove, 7 g of Mg and Ni in a mole ratio of 2:1 were subjected to an intensive mechanical grinding in a same high energy ball milling machine SPEX® 8000, using the same kind of crucible and steel balls. The only difference was that the rubber O-ring of the machine was replaced by a copper O-ring and the crucible was heated during the grinding step by means of an electric heating element wound around the crucible.
In this particular example, the grinding was carried out for 5 hours while the heating element was operated. After 5 minutes, the temperature was 150° C. After 10 minutes, it was 240° C. After 30 minutes, the temperature was 270° C. and it remained in the range of 290° C. for the balance of the process.
The X-ray diffraction spectrum of the mixture contained in the crucible after 5 hours of grinding at such elevated temperature is shown in FIG. 4. As can be seen, this spectrum is almost identical to the one that was obtained after 60 hours of grinding at ambient temperature (see FIG. 2).
The Mg 2 Ni crystallites that were so obtained had a grain size of 70 to 80 nm. There were bigger than those obtained at ambient temperature, but they were still nanocrystalline in structure, i.e. lower than 100 nm.
Thus, this example shows that when the grinding step is carried out at an elevated temperature, a nanocrystalline alloy can be obtained at a speed almost 10 times faster than when the same grinding is carried out at ambient temperature. Moreover, no subsequent annealing is required, since the annealing effect is already achieved during the grinding process.
EXAMPLE 2
Another sample of nanocrystalline Mg 2 Ni alloy was prepared, using the same amounts of metals, the same operative conditions and the same equipments as in example 1.
The only differences with example 1 were that:
the powder mixture used as starting material contained 5% by weight of carbon as a lubricant; and
the average grinding temperature was 200° C. (instead of 290° C.).
The following table gives the crystallite size, the stain and phase abundance after 3 to 8 hours of intensive grinding (milling).
TABLE 1______________________________________ Milled MilledCharacteristic Phase 3 hours 8 hours______________________________________Phase abundance Mg.sub.2 Ni 37% 97%(weight %) Ni 36% 3% Mg 27% --Crystallite Mg.sub.2 Ni 126 50size (nm) Ni 58 27 Mg 171 --Strain (%) Mg.sub.2 Ni 0.8 Ni 1.0 Mg 1.0______________________________________
FIGS. 5 and 6 show the hydrogen absorption rates of the Mg 2 Ni alloy that was obtained after 8 hours of milling at 200° C., after 3 and 4 absorptions, respectively. Such rates were measured at a pressure of 12 bars and a temperature of 300° C. for FIG. 5, and 200° C. for FIG. 6. Thus, the rate reported in FIG. 5 was obtained under the same conditions as used in the comparative example (see FIG. 3).
As can be seen, the absorption rate of the alloy prepared by milling in accordance with the invention, viz. at elevated temperature, is substantially faster than the absorption rate of the alloy prepared by milling at ambient temperature.
FIG. 7 is a curve showing the pressure-composition isotherm obtained with the above alloy milled for 8 hours at 200° C. As can be seen, this curve clearly shows the formation of a plateau both for absorption and desorption, like those that are obtained by subsequent annealing of a nanocrystalline alloy obtained by intensive mechanical grinding at ambient temperature (see, by way of comparison, FIG. 2 of the above mentioned article of L. ZALUSKI et al, Journal of Alloys and Compounds, 222 (1995) 53-57. Thus, the process according to the invention permits not only to prepare the hydrogen absorbing nanocrystalline alloy but simultaneously also to activate the same.
Of course, numerous modifications could be made as to the way of reducing to practice this invention depending on the kind of alloy to be prepared and the characteristics such alloy should have. Such modifications are obvious for one skilled in the art and would not depart from the scope of the appended claims.
|
A process is described for preparing a nanocrystalline powder of an alloy of at least two metals by an intensive mechanical grinding step performed upon powders of the metals which make up the alloy. The grinding is performed at atmospheric pressure under an inert atmosphere, and is carried out at a temperature in the range of 100°-400° C. In this manner, one obtains crystallites of the alloy having a grain size lower than 100 nm by grinding for a period of time lower by about an order of magnitude than the time necessary to achieve this grain size by a similar grinding step carried out at ambient temperature.
| 2
|
This invention relates generally to a spreader bar for picking up and laying soil erosion prevention mats. More particularly, the invention relates to a spreader bar having hinged hook carrying ends for engaging a soil erosion prevention mat formed by connecting a matrix of concrete soil erosion prevention blocks with cable or the like through passageways in the blocks, such as the soil erosion prevention blocks disclosed in my U.S. Pat. No. 4,227,829, and my co-pending patent application entitled Soil Erosion Prevention Block Insert and Apparatus for Positioning, Ser. No. 204,055, filed Nov. 4, 1980, which are hereby incorporated by reference herein.
Matrices of soil erosion prevention blocks are known in the art, as shown by my above-identified United States patent and application. In the prior art, soil erosion prevention blocks or other revetment structures were positioned one adjacent another to form a matrix of such structures on the embankment or inclined area to be protected from erosion. U.S. Pat. No. 3,597,928, Pilaar discloses a matrix of soil erosion prevention blocks adhered to a porous flexible mat, which is apparently placed on an inclined area to control erosion. A problem inherent in that construction is that a border of mat must extend out from the blocks a sufficient distance to permit the mat to be gripped so that the matrix can be moved. When matrices of blocks are laid, the border prevents positioning the blocks on neighboring mats adjacent one another.
A problem in the prior art above described is the speed and ease with which the blocks or mats may be positioned on the inclined area to be protected. The blocks either have to be positioned one at a time adjacent one another at the job site or in the case of Pilaar, the number of blocks formed in the matrix is substantially limited by the strength of the mat they are adhered to. Further, in the latter case, an apparatus for laying such mats is known which comprises a frame having ends for clamping the mat border. The apparatus includes rubber covered bars between which the mat is clamped for lifting the matrix. Naturally, the size of such matrix which may be picked up and laid is substantially limited by the clamping force and contact area between the bars and mats surface.
SUMMARY OF THE INVENTION
The present invention is directed to a spreader bar for picking up and laying a very large matrix of cable connected soil erosion prevention blocks. The invention is more particularly directed to a spreader bar for use with mats having loops of cable or the like at the ends thereof for lifting and laying the mat; such as a soil erosion prevention block mat in accordance with my U.S. Pat. No. 4,227,829. The block matrix disclosed therein has the two cables through the blocks connected together at the ends thereof to form loops for lifting the blocks.
The spreader bar of the invention includes hinged cable carriers at the ends thereof for engaging the ends of the mat. The loops are engaged by hooks at each end of the spreader bar fixed to a shaft rotatably mounted with the cable carrier. The hooks are thus rotatable from a retracted position in which the carrier is positioned adjacent the end of the mat to an engaged position where the hooks engage the loops of the mat's end, securely attaching it to the cable carrier. The mat may then be picked up with the spreader bar and laid down in the desired position adjacent other mats on the area to be protected from erosion. The spreader bar of the invention is particularly useful for laying soil erosion prevention mats where the mat must be released under water, such as at a shoreline, as the hooks are simultaneously released from the loops by the cable carrier of the invention.
Because the soil erosion prevention blocks are connected together by continuous cables, a large number of such blocks may be laid at one time, with the only limitations as to the size of the mat picked up being the strength of the cable therethrough or the lifting capacity of the spreader bar or lifting means.
It is therefore an object of the present invention to provide a new and improved spreader bar for picking up and laying down end-to-end and side-to-side large expanses of soil erosion prevention mat in a short amount of time and with a minimum of effort.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of the spreader bar of the invention.
FIG. 2 is a side view of the spreader bar of the invention.
FIG. 3 is a view of the spreader bar of the invention along lines 3--3 of FIG. 1.
FIG. 4 is a view of the latch of the invention along lines 4--4 of FIG. 3.
FIG. 5 is an isometric section through the cable carrier of the invention along lines 5--5 of FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, the spreader bar of the invention is indicated generally at 1 in FIGS. 1 and 2. The spreader bar comprises generally a frame 2 having two hinged cable carriers 3 mounted with the ends thereof. The frame may be constructed of steel I-beam, tube, or other material for strength depending upon the weight of the mat to be lifted, and includes two extended main beams 4. A number of cross beams 5 are provided fixed between the main beams 4, preferably by welding, to form a strong and rigid structure.
The frame further includes four frame extension plates 6 which are welded or otherwise fixed to the main beams 4. The ends of the frame extension plates have holes drilled therethrough for receiving the cable carrier hinge pins 8, as will be described later.
Two stanchions 9 are fixed to stanchion plates 10, which are likewise fixed, by welding or bolting to the main beams 4 of the frame. A cross member 11 is provided fixed between the stanchions to strengthen them under loaded conditions.
As best seen in FIG. 2, the stanchions cooperate with stanchion cables 12 to minimize bending of the frame when soil erosion prevention mats are lifted. The stanchion cables 12 are situated over the stanchions 9 and attached at either end to pad-eyes 13 welded to the main beams 4 of the frame. A number of lifting pad-eyes 14 are also provided fixed to the frame for lifting the spreader bar. It will be appreciated that when a lifting force is applied to the lifting cables 15 to raise the spreader bar, the weight of the mat attached to the cable carriers 3 will exert a force through the hinge pins 8 to the frame. This force creates a bending moment which tends to cause the main beams 4 to bend upwardly concave. The stanchion cables 12, being tightly connected to the pad-eyes 13 over the stanchions 9 thus exert a downward force on the main beams 4 at the stanchions and an upward force on the main beams at the pad-eyes 13 to counter the bending moment and minimize bending of the frame.
Referring now to FIGS. 3-5, the self stripping cable carrier 3 of the invention is illustrated. The cable carrier engages or releases the ends of the soil erosion prevention mat as desired by means of a plurality of hooks for engaging the loops 16 at the ends of the mat. Naturally, the width and design strength of the cable carrier may be varied according to the width and weight of mat to be lifted. The cable carrier includes from one to as many number of hooks needed to engage the cable loops of the mat, which will depend upon the width of the blocks of the mat and the positioning of the cables through the blocks.
The cable carrier comprises generally an upper beam 20 and a lower beam 21. A number of support plates 22 and a center support plate 24 are provided preferably welded between the upper beam 20 and the lower beam 21. Four of the support plates 22 are located so as to bracket the two frame extensions 6, and have openings formed therethrough for receiving the cable carrier hinge pins 8. The hinge pins 8 preferably include cotter pins 23 or the like therethrough to retain the pin 8 in the hinge assembly.
The support plates 22, 24 have openings therethrough for receiving a shaft 25, rotationally mounted with the support plates. Hooks 26 which may be standard cable hooks are fixed to the shaft, such as by welding, for engaging the cables of the mat. Stops 27 or the like, such as cotter pins, are provided mounted at the shaft ends to prevent lateral movement of the shaft with respect to the support plates.
In the preferred embodiment the outermost hooks 26a are offset outwardly on the shaft, as best seen in FIG. 3, while the rest of the hooks 26 are uniformly spaced apart. The hooks 26 are thus positioned to engage the mat cables at the approximate centerline of each row of blocks, thereby keeping the mat ends generally parallel to the plane of the hooks. By disposing the outer hooks 26a laterally outwardly, any tendency of the outer rows of blocks to tilt downwardly at their outer edges is counter-acted and the mat is more easily laid down, as the outer edges of the mat are maintained generally flatter which simplifies laying a mat adjacent another mat and are prevented from digging into the surface of the area to be covered with the mat. It has been found that an offset of 2 inches for the outer hooks are sufficient for this purpose when twelve inch square blocks are employed and the uniform spacing of the other hooks 26 is twelve inches.
The shaft 25 is preferably mounted through the support plates 22 and hooks 26 before the hooks are fixed to the shaft or the lower beam 21 is fixed to the support plates. As best seen in FIGS. 4 and 5, the lower beam 21 is preferably tubular so that the cables 16 when under load as the mat is lifted bear against the rounded surface of the lower beam 21. The lower beam 21 may be fabricated from standard steel tube stock and preferably has a longitudinally extended opening or slot formed therein to permit assembly of the lower beam around the shaft. The lower beam further includes a plurality of slots or openings 29 therethrough for permitting the hooks 26 to extend and move outwardly from the lower beam. The openings 28, 29 permit the lower beam 21 to be mounted around the shaft and welded to the support plates to complete the major assembly of the cable carrier 3.
An arm 30 is provided welded or otherwise fixed to the shaft 25 to permit rotation of the shaft to engage or disengage the cables. The cable carrier 3 preferably also includes a latch mechanism to safely lock the hooks in the cable engaging position. The latch mechanism comprises a latch bar 31 pivotally mounted with the arm in any suitable manner, such as by a latch bolt 33 through an opening in the arm, threadably engaged to the arm 30. The mechanism preferably includes a spring 32 urging the latch bar downwardly wherein it is behind a latch lug 39 fixed to the center support plate 24 to prevent rotation of the arm 30 and shaft 25 to the nonengaged position. The mechanism is released by pivoting the latch bar 31 upwardly until it clears the latch lug 39 and allows the shaft 25 to be rotated. The latch preferably includes an eye 44 fixed to the latch bar 31, to which a latch release cable 45 is attached. Simultaneously pulling the latch release cables 45 permits the mat ends to be simultaneously released.
To assist in disengaging the hooks 26 from the mat cables, a release cable 35 may be provided fixed to the arm 30 such as at opening 34 by any suitable means. The cable 35 is mounted around a pulley 36 which is rotatably mounted to the upper beam by means of pillow blocks 38 fixed to the upper beam and a shaft 37. With such a cable and pulley arrangement on both ends of the spreader bar, the hooks 26 are simultaneously disengagable from the mat cables by pulling the latch cable 35, such as with a winch (not shown). Cables for rotating the hooks and shaft may be provided if desired similarly mounted to the arm 30, however in that case no pulley is required as the arms 30 are moved inwardly of the cable carriers 3 to rotate the hooks to engage the cable.
The cable carrier also preferably includes a hook guard 40 welded or otherwise fixed to a lower beam 21. The hook guard 40 closes the end of the hook 26 when the cable carrier is in the engaged position, thereby securely enclosing the mat cable. The hook guard 40 may be fabricated from a continuous angle iron or the like. A plurality of guard braces 41, 43 fixed to the hook guard 40 and the lower beam 21 strengthen and position the hook guard 40 so that the end of the hook is safely enclosed.
A plurality of stripper ridges 42 are provided fixed to the lower beam adjacent the hooks 46. As best seen in FIG. 4, the stripper ridges aid in disengaging the mat cables from the hooks 26 by causing the mat cable to ride outwardly from the shaft and off of the hook 26. The stripper ridges are perferably formed from half round tubing and are welded on either side of and adjacent the hooks 26.
In operation of the spreader bar of the invention, the arm 30 is moved, rotating the shaft and hooks into the disengaged position. The spreader bar is then lifted, as described previously, by a crane or otherwise and situated over the soil erosion prevention mat to be moved. It should be noted that it is preferable that the frame length, as measured between the hinge pin 8 centers, be approximately 11/2 feet longer than the mat, where the mat cables form loops extending 11 to 13 inches from the edge of the mat. For lifting other mats, it is preferable that the frame be sized such that the cable carriers when positioned over the mat cables are located so that the hooks are over the mat cable loops and when rotated, they engage the mat cables. When the cable carriers are thus positioned over the mat, the arm 30 is rotated inwardly and downwardly to rotate the hooks and engage the cable loops until the latch bar 31 can pivot behind the center support plate 24 to lock the cables between the hooks 26 and hook guard 40. If necessary, the cable covers may be rotated to permit the hooks 26 to engage the mat cables. The spreader bar may then be lifted.
The mat when lifted assumes a concave configuration, causing the cable carriers to rotate inwardly. The spreader bar and mat may then be positioned with the crane where desired and the spreader bar lowered. As the mat is laid down, the cable carriers will return to their original position. The hook guard 40 effectively locks the mat cables onto the hooks until the mat is desired to be released. To release the mat, the latch bar 31 is pivoted upwardly until it is disengaged from the center support bar 24 and the arm rotated. Rotation may be accomplished manually or by means of a winch or like device as discussed previously however, it has been found that in most cases the weight of the hooks will rotate the shaft 25 until the cables 16 are disengaged. The stripper ridge is important in disengaging the hooks 26 from the mat cables, in that as the hook is rotated, the mat cable rides outwardly over the stripper ridge and off of the hook 26.
From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.
It will be understood that certain features and subcombinations are of utility and may be employed with reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.
As 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.
|
The invention relates to a spreader bar for picking up and laying down soil erosion prevention mats formed by connecting a matrix of soil erosion preventing blocks with cable or the like through passageways therein.
| 4
|
[0001] This application is a Continuation of, and claims priority under 35 U.S.C. § 120 to, International application number PCT/CH03/00133, filed 21 Feb. 2003, and claims priority under 35 U.S.C. § 119 to German application number 102 11 141.3, filed 14 Mar. 2002, the entireties of both of which are incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention concerns the field of gas turbines. It concerns a method for igniting the combustion chamber of a gas turbine unit and an ignition device for carrying out the method.
[0004] 2. Brief Description of the Related Art
[0005] The continuous combustion in the combustion chamber of a gas turbine is initiated when an external ignition source ignites the combustion mixture (usually an air/fuel mixture). Usually this is accomplished with electric sparks that ignite the mixture in the combustion chamber either directly or indirectly using a so-called pilot burner. Alternative ignition sources provide the required energy via a glowing surface or a laser light source. The ignition plug for generating the ignition spark requires high electric voltage directly in the combustion chamber. The supply line, especially the isolation of this high voltage line that must be comprised of ceramics due to the existing temperatures at the compressor exit, is relatively susceptible to heat expansion and vibrations. This is why such ignition systems are comparatively sensitive and must be replaced relatively often during the life of a gas turbine. This could result in low availability of the unit. The other known ignition by way of an auto-ignition avoids the supply of high voltages; however, the ceramic glow element itself currently does not have a long enough lifecycle.
[0006] In a completely different technical field, i.e., in military applications, it is necessary to initiate a chemical reaction with very simple, robust devices. This led to the development of so-called Resonance Igniters that utilize the heating of gas for ignition purposes with the gas supercritically dissipating its pressure energy into heat in a resonance tube. Usually solid reaction mixtures or—using a H 2 /O 2 and/or H 2 /air ignition flame—other fuels are being ignited (ref. for example U.S. Pat. No. 3,994,232 or U.S. Pat. No. 5,109,669).
SUMMARY OF THE INVENTION
[0007] The aspect of the invention includes a method for igniting the combustion chamber of a gas turbine unit as well as an ignition device for carrying out the method that avoids the disadvantages of known methods and devices and that is characterized by a simple and sturdy design, a high level of availability and operational safety, the absence of electric devices and easy integration into existing units.
[0008] A principle of the present invention is to use the known resonance ignition for igniting the combustion chamber of a gas turbine unit in which a compressed gas with a supercritical pressure ratio is discharged through a nozzle and, interacting with a resonance tube arranged behind the nozzle, is heated up to a temperature that is suitable for igniting carbon hydroxide and in which the heated-up gas is used directly and/or indirectly for igniting the fuel/air mixture introduced in the combustion chamber.
[0009] In a preferred embodiment the combustion chamber comprises a combustion space to which a flame tube of a pilot burner is connected that discharges into the combustion space of the combustion chamber. Ignition fuel and ignition air are introduced into the flame tube and the ignition fuel/ignition air mixture is ignited in the flame tube.
[0010] It is possible to use different gases for the resonance ignition. The preferred compressed gas is air because it does not require any additional heating up of the gas.
[0011] If the compressed gas used is something other than air, especially nitrogen, ignition air is used for the ignition and the ignition air requires heating up.
[0012] In accordance with a preferred embodiment of the invention an ignition space that leads into the flame tube is arranged between the flame tube and the resonance tube. When part of the air that is heated in the resonance tube is supplied to the ignition space through an ignition opening in the resonance tube, it is mixed with the ignition fuel in the chamber and ignites. The remaining part of the discharged air in the resonance tube preferably is removed passed the ignition space into the flame tube.
[0013] Alternatively it is possible for the ignition fuel/ignition air mixture in the flame tube to be ignited when it comes into contact with a heated surface of the resonance tube.
[0014] It also is possible for the entire decompressed air in the resonance tube to be used for igniting the ignition fuel/ignition air mixture.
[0015] The method in accordance with the invention is especially easy to implement when the already present fuel in the gas turbine is being used as ignition fuel.
[0016] However, it also is possible to use an ignition fuel that is different from the fuel in the gas turbine, especially methane or propane.
[0017] Ignitability can be improved if oxygen is added to the air that is heated up in the resonance tube and/or to the remaining air that is discharged in the resonance tube.
[0018] It is especially easy to integrate the method in a gas turbine unit with a compressor for compressing the combustion air when the compressed air for igniting the combustion chamber is removed from the compressor and/or an external ignition air supply.
[0019] The ignition device in accordance with the invention preferably is designed so that a flame tube is connected to the combustion space of the combustion chamber and that at least part of the gas that is discharged through the nozzle into the resonance tube flows into the flame tube through an exit channel arranged outside the resonance tube.
[0020] In a further development of this embodiment the entire gas discharged through the nozzle into the resonance tube flows through the exit channel outside the resonance tube whereby a heated surface of the resonance tube is adjacent to the flame tube.
[0021] In a further development of this embodiment the resonance tube is adjacent to an ignition chamber which in turn flows into the flame tube. A part of the gas in the resonance tube flows directly from the resonance tube into the combustion chamber through an ignition opening.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The invention is explained in more detail using exemplary embodiments in connection with the drawing, with the figures showing the following:
[0023] FIG. 1 parts of a longitudinal section of a first preferred exemplary embodiment of an ignition device in accordance with the invention with an ignition space being arranged between flame tube and resonance tube in which directly heated gas exits from the resonance tube;
[0024] FIG. 2 in a presentation comparable to FIG. 1 a second exemplary embodiment of an ignition device in accordance with the invention in which the resonance tube with a heated surface is directly adjacent to the flame tube;
[0025] FIG. 3 a device scheme for the supply of compressed air to an ignition device in accordance with the invention that is arranged in a gas turbine unit;
[0026] FIG. 4 in a presentation comparable to FIG. 1 a third exemplary embodiment of an ignition device in accordance with the invention in which the resonance ignition is arranged inside a modified ignition torch and
[0027] FIG. 5 in a presentation comparable to FIG. 1 another exemplary embodiment of an ignition device in accordance with the invention in which the resonance tube is directly connected to the fuel tube.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] FIG. 1 shows parts of a longitudinal section of a first preferred exemplary embodiment of an ignition device in accordance with the invention. The ignition device 10 is based on a configuration that is described in FIG. 1 of EP-A1-0 992 661. The hot gasses required for driving the gas turbine are generated by combusting a gaseous and/or liquid fuel in combustion space 11 of a combustion chamber ( 30 in FIG. 3 ). The combustion space 11 has a lateral combustion space wall 12 . A flame tube 13 discharges into the combustion space 11 through an opening in the combustion space wall 12 . In the illustrated example the flame tube 13 is concentric as it relates to a central axis 14 . Fuel is introduced to the flame tube 13 through a central fuel tube 23 .
[0029] While in the device according to FIG. 1 of EP-A1-0 992 661 combustion air is introduced into the flame tube through an air supply ( 70 ) that concentrically surrounds the fuel tube ( 23 ) and an ignition electrode ( 51 ) is arranged for the ignition that protrudes into an ignition space ( 50 ) that is filled with air and fuel from the fuel tube and the air supply via connecting channels ( 55 , 56 ), the (sensitive) electric ignition is replaced with a robust resonance ignition in the ignition device 10 according to FIG. 1 of the present application.
[0030] The object of the invention is to increase the availability of the gas turbine by providing a robust ignition lance without any electric components. The resonance ignition is based on the following principle: If a compressed gas (e.g. air) is discharged through a nozzle, the gas initially cools off since the pressure energy is converted to kinetic energy. If, however, it is discharged with an exceedingly supercritical pressure ratio, the pressure inside the gas is much higher than in the surroundings. This leads to post expansions that discharge the pressure to ambient pressure through compression waves. These compression waves dissipate strongly, i.e. the existing pressure energy is converted to heat. If the flow is decelerated as well, the kinetic energy is also available in the form of heat. This means the largest part of the original pressure energy can be converted to heat.
[0031] In the ignition device 10 of FIG. 1 the concentric external air supply is interrupted. Air in an ignition gas tube 22 that runs parallel to the fuel tube 23 is discharged through a nozzle 21 (can also be a Laval nozzle) before it reaches the flame tube. In the space behind the nozzle a resonance tube 19 is arranged in the symmetry axis 15 of the ignition device with the tube being open towards nozzle 21 . The gas (air) that flows from the nozzle 21 directly reaches the resonance tube 19 . By designing the resonance tube 19 accordingly that is arranged directly at the exit of nozzle 21 it is possible to generate strong temperature increases at the opposite end of the resonance tube 19 that is partially or completely closed. For ignition purposes a small part of the air (ignition air) that is injected into the resonance tube is heated up to above the ignition temperature of hydrocarbons. This ignition air is supplied to a subsequent, separate ignition space 16 arranged between resonance tube 19 and flame tube 13 through a small ignition opening 20 of the resonance tube 19 . Here it is mixed with fuel and ignites. The remaining discharged air is removed parallel to the resonance tube 19 and the ignition space through an exit opening 17 and an exit channel 18 . However, it is possible to use the remaining air and/or all of the supplied air for igniting the mixture. If compressed air is used as resonance gas, pressure in excess of 10 bar is required to reach the ignition temperature. It is therefore suggested to supply air with pressure around 10 bar (or more) and to heat them to ignition temperature by way of a resonance tube.
[0032] The fuel of the gas turbine is to be mainly used as ignition fuel. An alternative is to use other fuels such as methane or propane, for example, that are currently in use.
[0033] In the ignition device 24 shown in the exemplary embodiment of FIG. 2 the end of the resonance tube 19 that is opposite the nozzle 21 is completely closed. There is no ignition space so that the closed end of the resonance tube 19 and its heated surface are in direct contact with the gas in the flame tube 13 . The entire air that is discharged through nozzle 21 is removed through the exit opening 17 and the exit channel 18 into the flame tube 13 . In addition, oxygen 26 can be added to the ignition gas tube 22 and into the exit channel 18 by means of an oxygen channel 25 .
[0034] According to FIG. 3 the ignition device 31 can easily be integrated into a gas turbine unit 27 : The gas turbine unit 27 comprises a compressor 28 for compressing the combustion air that is supplied via the combustion air inlet, a combustion chamber 30 and a gas turbine 29 in which the hot gasses from the combustion chamber 30 are discharged and then are supplied to an exhaust gas outlet 39 to a flue or waste heat steam generator. Depending on the compressor pressure of the gas turbine 29 the air can be supplied via the gas turbine 29 itself and/or via the external ignition air supply 35 . From the two alternative sources the compressed air is supplied to an ignition air storage 34 via check valves 36 , 37 and from there it can be fed, as needed, into the ignition device 31 via a valve 33 . The necessary ignition fuel is provided via an ignition fuel supply 32 . The required resonance heating can be accomplished with a propellant other than air (e.g. N 2 ) if this is more readily available. In this case, however, the necessary ignition air must also be heated. This can be accomplished through a hot surface or a mixture of heated propellant or a part of it.
[0035] The ignition by means of the heated up surface of the resonance tube ( FIG. 2 ) is also possible when air is used as a propellant. Ignitability can be improved when oxygen is added to the resonance gas and/or into the remaining discharged air that is to be dissipated.
[0036] In principle the described method can be integrated into different geometires. Due to its compact design, however, it is especially advantageous to design the resonance tube 19 such that the currently electric component ( FIG. 1 of EP-A1-0 992 661) is simply replaced with the resonance tube with compressed air supply 21 , 22 . Analogous to FIGS. 1 and 2 it is possible to use a resonance ignition device comprising a resonance tube 19 , nozzle 21 and ignition gas tube 22 according to FIG. 4 . The resulting ignition device 40 can be integrated into a common ignition gas flare. The remaining discharged air that is not introduced into the ignition space 16 through the ignition opening 20 , reaches an exit chamber 42 via an exit opening 41 and from there reaches the flame tube 13 through a connecting channel 43 .
[0037] In the exemplary embodiment in FIG. 5 fuel is added through a comparatively narrow connecting channel 46 from the fuel tube 23 to the air that is discharged through nozzle 21 and heated in the resonance tube 19 . The resulting mixture is ignited and exits from ignition openings 45 on the closed side of the resonance tube 19 into the flame tube 13 and results in the ignition of the fuel/air mixture in the flame tube 13 .
[0038] List of Reference Numerals
[0039] 10 , 24 , 40 , 44 ignition device
[0040] 11 combustion space
[0041] 12 combustion space wall
[0042] 13 flame tube
[0043] 14 central axis (ignition device)
[0044] 15 symmetry axis
[0045] 16 ignition space
[0046] 17 , 41 exit opening
[0047] 18 exit channel
[0048] 19 resonance tube
[0049] 20 , 45 ignition opening
[0050] 21 nozzle
[0051] 22 ignition gas tube
[0052] 23 fuel tube
[0053] 25 oxygen channel
[0054] 26 oxygen
[0055] 27 gas turbine unit
[0056] 28 compressor
[0057] 29 gas turbine
[0058] 30 combustion chamber
[0059] 31 ignition device
[0060] 32 ignition fuel supply
[0061] 33 valve
[0062] 34 ignition air storage
[0063] 35 external ignition air supply
[0064] 36 , 37 check valve
[0065] 38 combustion air inlet
[0066] 39 exhaust gas outlet
[0067] 42 exit chamber
[0068] 43 , 46 connecting channel
[0069] While the invention has been described in detail with reference to preferred 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.
|
In a method for igniting the combustion chamber of a gas turbine unit, a safely working ignition and a long lifetime of the ignition device ( 10 ) is achieved by discharging a compressed gas with a supercritical pressure ratio through a nozzle ( 21 ) and heating it up to a temperature sufficient to ignite hydrocarbons by interacting with a resonance tube ( 19 ) arranged behind said nozzle ( 21 ), and using said heated-up gas to directly or indirectly ignite a fuel/air mixture introduced into said combustion chamber.
| 5
|
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a submission to enter the national stage under 35 U.S.C. 371 for international application number PCT/EP2003/050349 having international filing date 29 Jul. 2003.
STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT
Not Applicable
REFERENCE TO AN APPENDIX
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a computer network for the configuration, installation, monitoring, error diagnosis and/or error analysis of plural technical-physical processes. These may be in particular electrical drive processes which run under control, regulation and/or monitoring by plural process computer nodes (in the example of an electric drive system: drive regulator). The process computer nodes are connected to at least one diagnosis computer node via a shared communication system. In the diagnosis computer node, one or more configuration, monitoring and diagnosis services or functions is/are implemented, which are allocated to the processes and/or the process computer nodes and/or to the data processing operations running therein.
The invention further relates to a diagnosis computer node for the said network. This is formed as a server with interfaces for at least one database and for communication with at least the process computer nodes and with other client computer nodes. The invention further relates to a communication computer node or a communication module, the latter being formed as a software and/or firmware module, which is respectively suitable for use in the said network.
2. Description of the Related Art
From a conference volume to accompany the congress “SPS IPC Drives”, which took place in Nürnberg in November 2001, the technical article “Info-Portal für anlagenübergreifende Prozessvisualisierung und -management via Internet” (authors: Andreas Kitzler und Werner Felten) was disclosed. This proposed a communication structure in which plural, mutually independent automation systems, cells or appliances may be combined, monitored, visualised and the like via an information port. At the information port, access can be gained to the Internet. The communication between the automation cells (known as Supervisory Control and Data Acquisition—SCADA) on the one hand and the central web server of the information port on the other is effected via standard interfaces on the basis of the extensible mark-up language XML. To this end, each automation system is provided with what is known as an XML-agent for communication with the information port on the basis of TCP-IP. Thus management should be able to evaluate in a qualified manner various automation cells or SCADA systems via the web. However, the individual sensor data have to be collected on the level specific to them, prepared there and made available to the information port via the XML agent before they can be transported from the information port via the web.
From DE 196 14 748 (A1-published and unexamined specification, and C2-patent specification), an error diagnosis system is known in which a diagnosis computer node communicates via plural bus systems also on the basis of the communication protocol TCP/IP (Transport Control Protocol/Interface Program) with control station computer, control process computer and field process computers. For communication between the field process computers on the one hand and the diagnosis computer node on the other, a serial field bus according to the standard RS485 is used, wherein the diagnosis computer node dominates the serial field bus (RS485) according to the master/slave principle. The bandwidth for the data transmission (RS485 interfaces) is not sufficient with the increasing data inundation. The data to be presented on the user interface cannot be transmitted quickly enough due to the ring communication structure within a field process computer cluster. It takes about 50-60 ms to scan one parameter—in appliances with about 500 drives, for example, any error occurring would only be notified after more than a minute. Each parameter is transmitted individually, and the transmission of software packages is not possible.
BRIEF SUMMARY OF THE INVENTION
The object of the present invention is to develop a hardware and in particular software tool for the diagnosis of complex technical appliances and systems which is tailored to the requirements and needs of the user and in particular meets the following requirements:
Versatile functions for monitoring and diagnosing large drive systems:
The object of the invention is to develop a hardware and in particular software tool for monitoring and diagnosing in particular large drive systems. The diagnosis system is intended to offer comprehensive, versatile functions which are tailored to the currently very different needs of the various user groups of the client.
(2) Easy-to-use, transparent user interfaces:
The user interface of the diagnosis system is the only part of the software with which the client comes into contact. In this sense it is the “bulletin board” of the software and is critical for acceptance and judgment thereof by the client. In planning the user interface, this should be so contrived that it is easy to use even by not very highly trained staff. The large number of data to be indicated in the diagnosis of large appliances must be graphically prepared and presented in an ergonomic diagram to the user.
(3) Shortening of the time necessary to detect a possible error:
The usefulness of the diagnosis system to the client will be that he is presented with data necessary for detecting and correcting the error immediately after an error has occurred. Thus the time can be reduced during which the appliance is not productive.
(4) Situation-dependent presentation of diagnosis data
The diagnosis system should make available the right data at the right time at the right place:
Preparation of the diagnosis information according to the requirements of the respective user circle (e.g. appliance operator, technician, installer)(→the right information) Indication close to the time of diagnosis data directly after an error has occurred (→at the right time) Access to THE DIAGNOSIS SYSTEM by any PCs of the client without installation cost—both in the local client network and via remote access (→at the right place).
(5) Reduction of critical appliance states by prophylactic maintenance and constant monitoring of the appliance:
In future, the diagnosis system is to contain mechanisms which help to detect possible oncoming failure of appliances and to inform the client. Thus the reliability of the drive system can be further increased.
(6) Comprehensive diagnosis/measuring operations via rapid Ethernet interfaces, including the Ethernet overall concept of the machine in order for example to measure, record and evaluate a reference signal of a real leading axle.
(7) Prophylactic diagnosis (e.g. transmitter failure likely in . . . days).
(8) An “expert system” is intended to ensure error localisation within 10 minutes maximum and simplify error correction substantially.
(9) Web browser functions.
(10) The diagnosis system must be able to run on plural platforms (e.g. diverse control stations).
(11) Integrated data protocolling/analysis (register values, commands) must be available without additional hardware (data analyser).
(12) Cyclical data protocolling at a central database server.
(13) Access option for the machine manufacturer to drive systems supplied via remote diagnosis.
(14) Operator guidance and parameter handling (configuration, installation, error search, software updates) are to be substantially improved.
(15) Development of branch-overlapping solutions
In spite of taking clients' wishes into account, the diagnosis system for branch-overlapping use is to be developed so that use in other branches (e.g. machine tools, textile machines) is possible without great complication/expense.
(16) Preparation of software tools for the installation of drive systems with in future up to 500 axles
Drive systems with more than 300 axles can only be installed without software support with excessively high cost. To this end, with the diagnosis system according to the invention a suitable software tool is to be developed.
(17) Shortening of the installation time and reduction of the installation costs:
By means of the diagnosis system, the costs of installation are to be reduced in the long term by the delivery of suitable software-supported methods.
(18) Worldwide access to the technical-physical processes of the appliance, in particular drive systems, for rapid, economical diagnosis:
For rapid and reliable service and for appliance diagnosis, worldwide access to the drive system will be possible.
On the other hand, in order to prevent the disadvantages from the prior art from arising in the computer network having the features mentioned in the introduction, it is proposed according to the invention that the shared communication system between the process computer node and the diagnosis computer node is realised with the Ethernet or another bus or communication system operating asynchronously and/or with a stochastic access method. An access method of this type is known for example under the abbreviation “CSMA/CD” (Carrier Sense Multiple Access/with Collision Detection). This industrial Ethernet use for realising a communication infrastructure permits a higher bandwidth for data transmission compared to the prior communication via RS485 and the associated USS protocol, so that larger quantities of data can be transmitted from the process computer node to the diagnosis computer node. There is an increasing need for this, due to the increasing complexity of the technical appliances with an increasing number of process computer nodes and associated technical-physical processes. Furthermore, the Ethernet has proved a substantial standard in offices for transmitting large quantities of data. By the use according to the invention of the Ethernet with the protocol TCP/IP also known per se, the path is cleared for the diagnosis system according to the invention to be compatible with and/or combined with the Internet. Thus the advantage is gained that diagnosis data can be sent via the Internet. In addition, a technical appliance can be monitored with a large number of processes from any client node, in particular via the Internet.
In order to be able to process the extensive quantities of data arising in a practical manner, a decentralised diagnosis together with pre-processing is advantageous. It is also practical to move extensive diagnosis functions as close as possible to the technical-physical process or apparatus concerned. In this respect, according to an advantageous embodiment of the invention, a communication unit or computer node is interposed between the Ethernet or the other bus or communication system and at least one of the process computer nodes, thus connecting the respective process computer node to the Internet or other bus or communication system. The communication computer node or communication unit can additionally also undertake event- and/or enquiry-based communication to the diagnosis computer node.
In particular, when in a further configuration of the invention the communication unit or the communication computer node is so formed that it communicates via XML protocol and/or as an XML-based interface (XML—Extensible Markup Language) with the diagnosis computer node, in projecting and configuring the technical appliance to be monitored thereby, it is possible to react very flexibly and with relatively low cost to technical requirements and client wishes. On the basis of the invention, a standardised, versatile network-computer structure can be created, which can be easily extended by further functions. Particularly, with the use of XML protocol and/or XML-based interfaces, the diagnosis data can be so prepared from the process computer node and/or communication node for the diagnosis computer node that these data can be transmitted easily via the Internet from the diagnosis computer node to client computer nodes.
In order to be able to manage the extensive quantities of data in a practical manner via decentralised pre-processing, according to one embodiment of the invention it is provided that the communication unit or communication computer node is provided with functionalities for error search or diagnosis in the region of at least one of the process computer nodes or of a technical-physical process. With this notion, extensive diagnosis functions can be located close to the components concerned.
The Internet-compatibility of the diagnosis system according to the invention is enhanced if according to an embodiment of the invention the diagnosis computer node is formed to make available or at least support web-based user interfaces for client computer nodes. This can be effected via data remote transmission and/or a long-distance traffic network (e.g. Internet). It is further within the scope of the invention if in addition the diagnosis computer node is provided with function components which support the education of the user interfaces in the client computer node.
It is problematic whether the user at a client computer node must confident that the client user interface is reproducing (diagnosis) data and information which are still substantially up-to-date or close in time. Any failure of the diagnosis server should be detectable, and furthermore errors and other events in the technical-physical process and/or process computer node are to be capable of being communicated to the user close to time via the user interface of the client computer node allocated to him.
To solve this set of problems, within the scope of the general inventive notion, a diagnosis computer node having the following features is proposed for use as a server in the network outlined above:
The diagnosis computer node is set up to operate as a server and has interfaces to at least one database, for communication with the communication and/or process computer node and for communication with other client computer nodes; The one or more interfaces to the other client computer nodes are realised by using a Servlet container (known per se), which transmits diagnosis data to the client nodes; These diagnosis data are obtainable from the interfaces for communicating with the communications and/or process computer node; The one or more above-mentioned interfaces which are allocated to the communication and/or process computer nodes are realised on the basis of the Ethernet; A diagnosis channel is formed, which comprises one or more Ethernet interfaces, which are allocated to the communication and/or process computer nodes; The diagnosis channel further comprises an event management unit, which can access the database and can process diagnosis data obtained at the Ethernet interfaces; Further, the diagnosis channel comprises an event monitoring unit, which is formed on the basis of the Servlet container and makes available output data from the event management unit to one or more Applets on external client computer nodes.
It is thus possible to transmit data, in particular diagnosis data in cycles between the diagnosis computer node and the user interface of a client computer node. Thus a user at the client computer node can be informed close to time of events arising in the region of the process computer node and/or of the technical-physical processes. Thus a wide variety of appliance information can be made available on the user interface of the client computer node in a comfortable manner. The data transmission can be carried out particularly advantageously with Java technologies, in particular a Java Servlet on the diagnosis computer node as a server and a Java-Applet in the client computer node. Thus it is also possible to make available diagnosis information in the form of websites to a user on the client computer node. In this case, the use of Java-Applets offers very versatile representation options, which are easily extensible by bought-in Applets with graphical capabilities.
The solution to the above set of problems is assisted by the diagnosis channel according to the invention in the diagnosis server, by means of which a cyclic communication can be effected, wherein data packages are regularly exchanged. If a data package is missing, it can be detected in the client computer node that an error has occurred (“event+heartbeat”). The heartbeat corresponds as it were to the dead-man's button known in particular in the field of railway safety technology. By means of the diagnosis channel, therefore, a display of diagnosis data originating from the process computer node can as it were be triggered via diagnosis server or diagnosis computer node to the client computer node on his user interface. The representation of the error on the user interface is no longer dependent on an enquiry being sent to the diagnosis server by the client computer node due to the diagnosis channel according to the invention. Rather, the process computer nodes, optionally via individually allocated communication nodes, can itself indicate as it were new events, in particular errors. This mechanism is substantially supported by the diagnosis channel in the diagnosis computer node in that diagnosis or error data notified via the event monitoring unit by the process computer node are forwarded to the user interface of the client computer node for a user at that interface.
According to a particular configuration, the interfaces in the diagnosis computer node are contrived for communication with the communication and/or process computer nodes by means of XML protocols. Thus proprietary solutions which have restricted applicability are avoided.
In the diagnosis computer node, all diagnosis data are intended to be made available to the user interfaces on the client computer nodes in a web-based manner. It has turned out to be particularly advantageous for this purpose to have a combination of the web-server Appache with the Servlet-engine “Tomcat”.
In the diagnosis computer node according to the invention and indicated above, the diagnosis channel ensures in the case of an event, in particular error, to prompt a reaction from the client computer node thereto with his user interface. If an error or event occurs, corresponding diagnosis data are picked up at the Ethernet interface of the diagnosis channel, and are allocated to the communication units, communication and/or process computer nodes. The event management unit can access the diagnosis or event data in the form of a telegram for example at the Ethernet interface. The event or diagnosis data are processed and a corresponding datum is written into the database. The output data from the event management unit pass to the event monitoring unit applied in the Servlet container. In the example of the Intranet, this event monitoring unit transmits at its output a datum advantageously direct to the client computer node, without the interposition of a web server. The datum contains a prompt to demand representative diagnosis data from the diagnosis server due to events or errors. Thus the need for constant polling throughout the period of operation, which would require increased data transmission capacities, is avoided.
To connect the process computer node to the Ethernet or another asynchronously operating communication system with the diagnosis computer node, and in particular to create the option of an event-based communication between process computer nodes and diagnosis computer nodes, extensive diagnosis functions being located as close as possible to the technical-physical process, in the scope of the general inventive notion, a communication computer node or a communication unit are proposed as a software and/or firmware module, which is suitable for use in the computer network outlined above and is distinguished by the following features:
The communication computer node or the communication unit has a first interface which is allocated to the at least one diagnosis computer node; This interface is programmed or formed for communication via protocols of the TCP/IP family, including UDP/IP, preferably on the basis of the Ethernet; The communication computer node or the communication unit has one or more second interfaces which is/are allocated to one or more process computer nodes; The first and one or more second interfaces may be coupled together via one or more information brokers; The one or more information brokers are respectively set up in terms of program and/or circuit technology as sub-units for bidirectional, enquiry- and/or event-based data communication, which takes place between the first and the one or more second interfaces.
The purpose of the communication unit or communication computer node is to roll out all communication tasks between the process computer node and its outside world. This includes for example access to parameters of the process computer node, e.g. of the drive regulator, the down- and up-load of regulator firmware for example and associated data records, as well as the delivery of diagnosis functionalities.
With respect to the realisation of hardware of the communication node according to the invention, it might be advantageous to manufacture a free-standing structural unit with the communication functions incorporated therein and to mount this on the printed circuit board for the process computer node. Alternatively, the communication node hardware may be incorporated wholly or in part in the circuit on the printed circuit board of the process computer node and/or on that of the diagnosis computer node. Alternatively, it is within the scope of the invention to realise the communication node as a “PC” as it were with its own housing, which can be snap-fitted on to a rail-type mount for the process computer node.
As an operating system for the communication node according to the invention (communication unit or communication computer node), the use of Linux has been found advantageous. In addition, C++ is suitable as a sufficiently versatile and powerful programming language.
With the concept according to the invention of the communication node between the process computer and diagnosis computer, there is the option for transmitting data to the outside world via XML-based protocols (instead of proprietary protocols). With the mark-up language XML, which is widespread and known per se, for Internet applications in combination with the delivery of platform-independent XML parsers, there is the further option of simply exchanging data in heterogeneous system environments. By way of validation mechanisms (XML models) that are already available, the structure and admissible content of a telegram can be established simply, and testing for quality takes place automatically. As a character-based protocol, an XML-based telegram is easy to generate and if necessary to process by hand or by simple scripts.
In order to be able to implement the most extensive diagnosis functions as close as possible to the technical-physical process, according to an advantageous embodiment of the invention it is proposed that the one or more information brokers comprise function components which are formed to perform an error search or diagnosis in the region of the process computer node and/or technical-physical processes. In particular in this connection, a further advantageous embodiment of the invention involves the installation of interpreters for the loadability of scripts known per se on the communication computer node or unit, which interpreters are formed for access to function elements or functionalities in the information broker(s) for the purpose of carrying out monitoring and diagnosis functions. One advantage achievable thereby consists in the more effective error search: by means of the scripts in combination with the language PERL, in a relatively simple manner, efficient error search conditions can be installed or loaded by the diagnosis computer node on the communication node. Thus the functionality available on the communication node can be extended once again.
It is within the scope of the invention that the communication unit or the communication computer node in certain cases operates as a server with respect to the diagnosis computer node (as client) if on the part of the diagnosis computer node requirements are present at information services, which are to be realised for example by information brokers in the communication node.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
Further details, features, advantages and effects on the basis of the invention will appear from the following description of preferred embodiments of the invention and from the drawings given by way of example. The drawings show:
FIG. 1 a schematic appliance diagram of the diagnosis system according to the invention with local and worldwide access to diagnosis data;
FIG. 2 a schematic block diagram of an example of a communication system of an electric drive system provided with the diagnosis system according to the invention;
FIG. 3 shown in schematic block representation, the basic structure of the diagnosis system according to the invention;
FIG. 4 a detailed block diagram of the internal structure of the diagnosis computer node;
FIG. 5 a similar block diagram of the internal structure of the communication computer node;
FIG. 6 a user interface, by way of example, on a client computer node for an appliance-based appliance image with the example of a printing press, generated by means of a Java-Applet in combination with a corresponding Servlet on the diagnosis computer node;
FIG. 7 a further, similarly generated user interface via a drive-system-based appliance image with the example of a printing press.
In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific term so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word connected or term similar thereto are often used. They are not limited to direct connection, but include connection through other circuit elements where such connection is recognized as being equivalent by those skilled in the art. In addition, many circuits are illustrated which are of a type which perform well known operations on electronic signals. Those skilled in the art will recognize that there are many, and in the future may be additional, alternative circuits which are recognized as equivalent because they provide the same operations on the signals.
DETAILED DESCRIPTION OF THE INVENTION
According to FIG. 1 , an electric drive system for a large number of axles 1 to be driven synchronously with one another, e.g. of a printing press provided with a large number of electric motors 2 , each driving one axle 1 . The electric motors 2 are each triggered or regulated via respective converters 3 with upstream process computer nodes 4 , realised in the present printing press drive system as drive regulators. To communicate with a diagnosis computer node, respective communication computer nodes 5 are connected upstream of the process computer nodes. The converter 3 , the process computer node 4 and the communication computer node 5 can be incorporated structurally into a common assembly, as is shown in the drawing, which is housed in a respective switch cabinet 6 .
According to FIG. 1 , the diagnosis computer node can also communicate with a control station, plural client computer nodes for diagnosis and via an Internet router or ISDN or in an analogue manner via the Internet with one or more geographically remote client computer nodes for remote diagnosis. Thus the diagnosis data prepared at the respective drive process of the electric motors 2 by means of the process computer node 4 and/or of the communications computer node 5 may be retrieved via the diagnosis computer node both locally and from any other location.
According to FIG. 2 , the individual process computer nodes 4 are connected together in the context of a ring structure for synchronised communication, in which case one of the process computer nodes 4 (the one printed darker in each case in FIG. 2 ) always operates as the communication master. This simultaneously has an interface for asynchronous communication via the Ethernet with plural control computer nodes SPS. In order also to support cross-communication between individual rings with process computer nodes 4 , a multi-link controller MLC is also introduced as a structural element (known per se from U.S. 2003/0100961 A1).
In the reference plane, (diagnosis) data are constantly being required from the plane of the process computer node 4 . These are essentially system data such as status and error messages, maintenance data and records for quality control. In order to evaluate the data, a diagnosis computer node is available in the reference plane as is shown in FIG. 2 . In this case also, the Ethernet known per se is also made available as a communication medium both with the individual process computer nodes 4 and also with the diagnosis stations in the reference plane, which may form client computer nodes with the user interfaces. The OSI layer model known per se permits complex communication mechanisms between the process computer plane and reference plane. Since the diagnosis is to be effected independently of the remaining communication, each process computer node 4 is reachable via the Ethernet by the diagnosis computer node (and vice versa). Thus, inter alia, the advantage is gained that communication problems in the synchronised ring bus of the process computer node can be mutually detected.
Definition of important terms:
Event An event is a datum which is sent by a drive regulator (process computer node at the technical-physical process) upon occurring at the diagnosis server (diagnosis computer node). It appears in the event display of the user interface and in the logbook. Events are for example error messages, messages about the start/stop of records, maintenance messages etc. Every event has an unambiguous event identification via which an event description can be retrieved in the documentation.
Record With a record, any parameter curves can be picked up by any regulator and stored in a database.
Monitoring view The monitoring view is a graphic representation of one or more parameters of one or more regulators. It serves to monitor the values curve of these parameters for deviations from the norm (e.g. monitoring of the motor temperature).
Parameter list The parameter list contains all parameters available to one type of regulator.
Long-term record A record whose data are stored on the diagnosis server in a database. Opposite to ring memory record.
Ring memory
record A record whose data are stored in a ring memory of the process computer node. Only upon completion of the record can the data be stored on the diagnosis server.
Configuration
Wizard A sequence of individual pages on which the user can make settings. Each step in the configuration comprises a number of functions and is shown on one page. According to what the user does in the previous step, a corresponding consecutive page is displayed (e.g. in the configuration of the record: option in step 1: ring memory or long-term record: according to the selection, the user receives pages displayed for configuring the ring memory or the long-term record).
FIG. 3 gives an overview of the basic structure of the diagnosis system. The user has various web-based user interfaces available, which present him with the functionality of the diagnosis system in a manner suited to him. For operation of the system, it is unimportant whether the user is local to the appliance or at another location.
The functions desired by the user are forwarded by the user interfaces to the diagnosis computer node. Here, every functionality which is available in the interface is implemented. Further, the diagnosis computer node undertakes to store all the data occurring in the database DB. All data specific to the appliance such as for example the appliance configuration or component databases, all data specific to diagnosis such as e.g. long-term records or ring memory records and all data relating to application, are managed in the database.
If relevant data are made available for diagnosis by the control or control station e.g. of a printing press, these can be further processed by special components incorporated in the diagnosis computer node.
The tasks incoming from the user interface at the diagnosis computer node are processed there and converted into commands that will be understood by the corresponding regulator. The communication between diagnosis computer nodes and communication computer nodes with a connected regulator is effected via Ethernet and XML protocols supported thereon. At the communication computer node, the tasks received from the application server are carried out and the result is sent back to the diagnosis computer node.
Each of the supported process computer nodes, e.g. regulators, must offer an XML-based interface in order to permit the diagnosis computer node access to the required data. This can be effected e.g. by means of a communication computer node (“communication PC”), which is either incorporated in the process computer node (e.g. b maXX 4600) or is added to the process computer node as a plug-in card. Alternatively, the XML-based interface of the process computer node can also run without communication PC hardware as part of the diagnosis computer node. The communication between the interface units on the diagnosis computer node and the process computer node hardware is then carried out via proprietary protocols and RS232 or Ethernet.
The requirements mentioned in the introduction require a component-based, distributed architecture of the diagnosis system. According to the general principles of software development, data capture, data processing and data storage and the user interfaces are in modular form and are separate from one another. Thus a transparent and more calibratable structure is achieved, which can be easily extended by further functionalities. It can thus be ensured that the diagnosis system grows along with the increasing number of drives (calibratability). By the use of Ethernet and TCP/IP for the communication between the communication PCs, the diagnosis computer node and the applications, there is a substantially larger bandwidth available for data transmission. This results in a substantially faster diagnosis system than that of DE 196 14 748 mentioned in the introduction.
Further, the component-based structure simplifies coverage of the large function scope of the diagnosis system. For every user group, an user interface tailored to their individual needs can be developed, which has access to the underlying infrastructure (diagnosis computer node).
By separating user interface and implementation of the functionality in the diagnosis computer node, new applications can be developed in future with less expense. By using modem software technologies, the Internet can be used as a communication medium that is available and accepted worldwide. Thus it is not important whether monitoring of the appliance is carried out locally on site or from another site, e.g. the service department. By using current Internet browsers for the user interfaces, the installation costs for the user are substantially reduced and the number of hurdles for the user in using the diagnosis system is significantly reduced.
The component-based architecture furthermore permits the support of newly developed methods of monitoring and diagnosing drives in that new functions are incorporated as components in the diagnosis computer node.
Substantial advantages of the diagnosis system according to the invention consist in particular in the following:
The client has universal access by the web interface to the diagnosis functions:
The right information close to time at the right place Simple user interface by way of web browsers User guidance simplifies operation and configuration The web interface is platform-independent Operation possible via the Internet if desired.
(2) The client receives data concerning the state of the appliance which have been prepared for him:
Data preparation in the form of graphic representations Prophylactic diagnosis.
(3) The substantially extended diagnosis options permit:
Extended monitoring of the appliance Simpler localisation of the cause in the case of an error.
(4) The functions for installation support permit:
Faster installation→reduction in costs Improved quality of installation by specified and documented acceptance protocols.
A function group “software update” permits the installation or updating of a firmware of the process computer node e.g. to firmware. All actions carried out in this function group are detected in a log file. It is a precondition for installation or updating of the firmware that the regulators selected have unambiguous regulator identification. The following actions must be possible:
Selecting drives
The user selects the drives to be updated from a drive list.
2. Selecting firmware
The user selects the firmware which is to be loaded on to the drives to be updated.
3. Carrying out the software update
After the display of a warning notice, the software update is carried out.
A function group “configure events” offers the option of recording any events in the events display and in the logbook. The event broker present in the communication PC of the respective process computer node is configured by means of the functions mentioned below, so that it monitors the desired parameter combinations for occurrence of the configured event. If the event does occur, it is sent to the diagnosis computer node and is displayed there in the event display. The following actions may be possible for example:
Selecting drives
The user selects the drive for which an event is to be configured or deleted.
2. Configuring event
The user configures an event by means of a configuration wizard
3. Deleting event
The user deletes an event from a list with current events. Events which are present as standard, e.g. errors, cannot be deleted.
4. Sending event configuration to drive
The user sends the configured event to a drive selection and activates the same.
A function group “scripts” offers the option of carrying out complex diagnosis functions. In order to make complex enquiries of parameters, PERL scripts can be written which are sent to the corresponding communication PC and are executed there. The following actions are to be possible:
Loading of the script on to the server
The user loads the script from the communication PC of a drive on to the server.
2. Loading of the script to the drive
The user loads a script selected from a list on to a selected drive.
3. Editing script
The user edits a script.
4. Execution of the script on the communication PC
The user starts the script on a drive.
Below, an overview of the architecture of the diagnosis computer node of the diagnosis system is given. FIG. 1 shows a detailed structure of the diagnosis system. It consists substantially of three planes:
Client computer node with user interfaces
All functionalities of the diagnosis system can be operated via the user interfaces. For the user of the diagnosis system it should make no difference whether he is at the appliance in the local network or is connected to the application server via the Internet or a telephone dial-up connection.
Diagnosis computer node
This is the core of the whole application. Its functionality is divided into various components (managers). Each manager is self-contained and makes available its functionality to the web-based user interface or to other server components. All data necessary for the function of the manager are stored in the connected database. In order to ensure encapsulation and consistency of these data, access is only permitted to these databases via the functions made available by the manager. This also ensures that a change in the database structure of one manager does not automatically lead to changes at other managers.
In order to make available the functionalities of the managers to the user interfaces, a suitable infrastructure must be created (Tomcat Servlet container). For communication with the web interface for installation, monitoring and diagnosis, an Apache web server is to be used. This makes available HTML pages in which Java Applets are embedded. The data to be displayed on the interface is transmitted by means of SOAP (Simple Object Application-Protocol) to the appropriate units. The user interface retrieves e.g. a function of the appliance manager. The parameters to be transferred and the reference of the function are sent to the Intra- or Internet by means of the SOAP protocol. In order to ensure the transparency of current firewalls, the function retrieval is sent in the form of an HTTP telegram. A web server on the site of the application server receives the HTTP telegrams with the SOAP content and forwards them to the SOAP handler. The SOAP handler in the Tomcat Servlet container decodes the enquiry and retrieves the desired function from the appliance manager. The function is executed and the return values are in turn converted into the SOAP protocol and sent to the interface as an HTTP telegram.
An essential property of a diagnosis and monitoring system is that the user is informed close to time of events occurring at the appliance. This presents a problem for the architecture described above, since both for communication via SOAP and for the HTML pages, there is no event-based reporting. As a remedy, events occurring at the appliance, e.g. the occurrence of an error or the update of a parameter value in one interface, must be communicated via an event channel to the user interfaces or constantly polled.
Process computer node
The process computer node plane makes available to the diagnosis computer node the data from the process computer node. The process computer node must be connected. As already indicated, the diagnosis computer node consists of various encapsulated server components (managers) which make their functionalities available via the Tomcat Servlet container to the user interface or client computer node. The component-based structure is intended to ensure that the function scope of the diagnosis system can be extended. The managers are realised as Java components. The individual managers are described below.
The appliance manager contains all the necessary data about the configuration of the appliance. This contains data concerning the components present in the appliance, the grouping of components, addresses, etc. Functionalities are to be made available which permit the appliance configuration to be represented in the form of various overview images. Furthermore, all documentations are to be made available to the data contained in the appliance.
In planning the appliance manager, it should be ensured that by means of the functionalities of this component any appliances can be described in the field of drive technology.
The event manager administers all events occurring in the diagnosis system such as e.g. error messages or maintenance events. It gathers all events that have occurred in the form of logbooks and makes them available to the user in a configurable representation. Further, the event manager has functions by means of which any event monitoring can be defined which is then configured by the event manager on the corresponding regulators.
The record manager makes available functions by means of which any parameters from any regulators can be recorded. It offers various types of record which can be configured by the user. All data occurring in a record are stored by the record manager in a database and if required made available to other units, e.g. a graphics unit of the interface.
All functionalities in the diagnosis system are protected against unauthorised access. Every user has a user identity and belongs to a user group which allows him a rights profile for access to the functionalities of the manager. These data are configured and stored in the user manager. Every function in the managers has an unambiguous identification. If a user wants access to a function, first the user manager is asked whether the user has the appropriate rights to carry out this function. The database in which the user data are stored is to be password-protected against unauthorised access.
The logging manager gathers all logging data from the connected regulators and stores their log and debug messages in a database or in rolling log files.
The communication computer node or communication PC according to FIG. 5 carries out communication tasks between the process computer node and the outside world. The software structure for communication with the process computer node is described below.
Each appliance that is to communicate with the process computer node must respond thereto via a suitable software interface on the communication PC. By means of the communication PC, almost any software interface based on the Ethernet or a serial interface can be realised. The software architecture on the communication PC is described below. Classification into the overall concept can be deduced from the comments above. FIG. 5 shows the software structure on the communication PC or the process computer node.
Any functionality which is to be made available by the process computer node is realised in a software module (information broker or manager). For example, the information broker makes “parameters” available to a parameter interface via which any parameter of the process computer node can be read and written. The information broker “errors and events” presents any events and errors to the outside. The two information brokers “parameter demand data” and “cyclical setpoint values” carry out communication with the control. They are only available on the regulators which form the master in the sercos ring and thus must communicate with the control. The information broker “software download” delivers functions for automatic up- and download of the regulator firmware. A parameter manager (not shown) acts as internal management of the regulator parameters on the flashcard. It is not relevant to the communication with the outside world.
The communication of the information brokers “parameters”, “error and event” and “software download” with the outside world is effected via XML-based protocols. All enquiries or responses are transmitted in XML messages defined by means of an XML model.
Each of the available brokers can process more than one enquiry at a time from one or more clients. Essentially, the communication PC of the process computer node communicates with the control and the diagnosis computer node. In communication with an SPS control, it must be ensured that the messages are processed in each case without an unnecessary time lag at a process of the process computer node, as these are of substantial significance for operation of the appliance. Since the enquiries can only be processed sequentially on the processor of the process computer node, it must be possible to process enquiries from the SPS control in strict precedence. This should be ensured by allocating priorities for the enquiries. Each enquiry to one of the brokers on the communication PC is provided with a priority. According to this priority the enquiry is preferred or treated as subordinate.
In addition to the information brokers, there are further, in part optional, software modules on the communication PC:
A logging server receives log and debug messages from the information brokers and makes them available to the outside world. A web server offers a simple web interface for operation and configuration. An FTP server gives simple up- and download of firmware on to the process computer node. A client for time synchronisation supplies a matching time to all communication PCs of an appliance. By means of a PERL interpreter, any scripts can be carried out with diagnosis or control functionalities. The configuration manager carries out starting of important services (e.g. automatic configuration of event monitoring for an error in the technical- physical process) and management of the configuration data of the individual software modules. A Telnet access is available for maintenance purposes.
The software modules of the communication PCs are described below.
The object of the information broker “parameters” is to prepare XML-based parameter interface for access to the parameters of the process computer node. As protocol, an XML-based protocol defined by means of an XML model is used, which communicates via TCP/IP with the client. From the viewpoint of the client, the following functions should be available:
Reading of parameters
The information broker “parameters” should be able to read a group of any parameters from the processor of the process computer node. In this case, in addition to once-only reading, the cyclical reading of parameters should be possible. The client is to be able to set the interval between reading operations and the number of reading operations.
Writing of parameters
The information broker “parameters” should be able to write a group of any parameters on to the process computer node.
The task of the information broker “errors and events” is to prepare an XML/based interface, via which a client is informed of events occurring at the regulator, without constantly having to enquire of the regulator. As a protocol, an XML-based protocol defined by means of an XML model is used, which communicates with the client via TCP/IP. From the viewpoint of the client, the following functions are to be available:
Configuration of event monitoring
At the information broker “event”, it will be possible to specify any entry conditions for an event, upon the occurrence of which a message is sent to the client. If the event has occurred, in addition to the parameters taking part in the entry condition, it will be possible to scan further parameters from the regulator.
An accepted task will be confirmed by the broker.
The information broker “event” will have extensive functionalities which offer the client wide-reaching possibilities of forming entry conditions. An entry condition will be composed of plural parts, which can be linked together logically by AND or OR. Within each partial condition, the value of the parameter currently scanned can be compared either to a comparative value sent within the configuration message or to the most recently read parameter value. Optionally, a tolerance limit can be taken into account, which is settled with the comparative value. For the comparison, both all logical operators (<,>,<=, >=, |=) and the comparison to a bit mask are to be carried out. In addition, for each partial condition, a trigger mode is to be taken into account which indicates whether the event is to be sent the first time the event condition is encountered, upon disappearance of a condition already encountered, or in both cases.
Notification of an event
When the configured event condition is encountered, an XML message is to be sent to the client.
Ending of event monitoring
By means of an XML message provided for this purpose, event monitoring in progress can be ended.
Enquiry of the status of event monitoring
By means of an XML message provided for this purpose, the client can enquire of the information broker “event” whether event monitoring is in progress or has already finished.
A difference from the information broker “parameters” is that there is no permanent socket connection to the client. After the configuration of the event, this is dismantled and only if the configured event arises is it re-assembled. To this end, on the part of the client a corresponding server port must be available.
The information broker “cyclical setpoint values” effects part of the communication with the control. It is used in particular with printing press applications provided there is a process computer node or regulator which is a sercos master in a drive ring.
The task of the information broker “cyclical setpoint values” is to supply the regulator at regular time intervals with new setpoint values from the control. In this case, it receives telegrams sent from the control and forwards them to the regulator. It should have the following capabilities:
Receiving of setpoint value telegrams from one or more controls
The information broker “cyclical setpoint values” will be capable of receiving setpoint value telegrams from one or more controls. The communication with the control may run via a proprietary protocol and/or the protocol UDP/IP.
Forwarding of setpoint values to the regulator
All setpoint value telegrams received by a control SPS will be forwarded with the highest priority to the process computer control or regulator.
Monitoring of the setpoint value telegrams
For diagnosis purposes, it will be possible to forward the incoming telegrams from the control both to the regulator and additionally to the diagnosis system.
The information broker “parameter demand data” effects some of the communication with the control. It is used particularly in printing press applications provided it is a process computer node or regulator which is the sercos master in a drive ring.
The task of the information broker “parameter demand data” is to make available any parameter values to one or more controls close to time. It will have the following capabilities:
A control client sends any parameters in a requirement telegram to the information broker. This requests the parameter values with a high priority from the regulator and sends back a reply telegram to the control client. For communication with the control client, a proprietary protocol and/or TCP/IP may be used.
Monitoring of the requirement telegrams
For diagnosis purposes, it will be possible to forward the incoming telegrams from the control both to the process computer node or regulator and additionally to the diagnosis system.
The task of the information broker “software download” is to transmit the regulator firmware and complete data records between the diagnosis computer node and the regulator. The transmission of data is effected by means of the FTP protocol. It will have the following capabilities:
Download of a regulator firmware to the regulator as process computer node
The download of regulator firmware is effected in two stages: first by means of an FTP client the firmware is transferred in a list on the flashcard of the communication PC. In the second stage, the information broker “software download” is instructed by means of an XML telegram to change the boot settings of the regulator in such a manner that the next time the regulator is booted up the new firmware is started.
Upload of a regulator firmware as process computer node
The upload of a regulator firmware is effected direct via the FTP protocol. In this case, no support on the part of the information broker “software download” is necessary.
Download of a complete data record
As in the download of a regulator firmware, the download of a parameter data record likewise takes place in two stages:
First, by means of an FTP client, the data record in a list on the flashcard of the communication PC is transferred. In the second stage, the information broker “software download” is instructed by means of an XML telegram to change the settings of the regulator in such a manner that the next time the regulator is booted up the new data record is taken into account.
Upload of a complete data record
The upload of a data record is effected direct via the FTP protocol. In this case, no support on the part of the information broker “software download” is necessary.
The task of the connection manager is to administer the interface to the regulator or process computer node. In this it will be possible to manage various physical interfaces (e.g. serial, Ethernet or SPI). Each enquiry to the connection manager is provided with one or 5 priority levels. Enquiries with the highest priority are sent by the connection manager to the (digital signal) processor process computer node before all other enquiries awaiting a response. Enquiries with a low priority are always dealt with after all other tasks awaiting. Thus it can be ensured that a task with the highest priority, e.g. from the control, is always processed as the next enquiry on the process computer node.
In the process computer node, as a memory means a flashcard is allocated to the communication PC due to the improved support by the Intel PXA 255. However, for the process computer node or regulator, there has to be an option of reading parameters from the flashcard and to write them on to the flashcard. This is ensured by means of the parameter manager.
Further services on the communication PC
Logging servers
All notices generated in the information broker processes are formatted and written to the console, into a log file or a message queue of the log server. This log server can then send the messages to any servers/computers.
In order to permit subsequent evaluation of the log files, various message types are specified which simplify the interpretation of the messages (e.g. debug, data, error . . . ).
Script support
By means of script support on the communication PC, a versatile and freely programmable interface is to be created, with which future requirements of monitoring and diagnosis are to be covered. By means of a PERL interpreter, any scripts can run on the communication PC, which have access to the functionalities of the information brokers “parameters” and “errors and events”. Thus relatively complex monitoring functions can be carried out locally on the communication PC without loading the network by transmitting data. The scripts are transmitted by means of the FTP server to the communication PC or are already present there as part of the software.
Due to the strenuous requirements for performance and system resources of the communication PC, the script support is only to be used for special diagnosis tasks.
Time synchronisation, FTP server, Telnet
For synchronisation of the system times, all communication PCs will synchronise their system time regularly via a time server running on the BAUDIS.
The FTP server and Telnet access serve for software updating of the communication PC and for maintenance.
Diagnosis data arising during operation of the drive system (e.g. errors or diagnosis information such as e.g. temperature, speed, contouring error, deviation from rules) are polled by the communication PC on the process computer node or drive regulator and converted into an XML-based protocol. The communication PC makes the diagnosis data available to the diagnosis computer node in an event-based manner (information broker “event”) or in an enquiry-based manner (information broker “parameter”).
In the managers of the diagnosis computer node, the diagnosis data are retrieved or received in an event-based manner from the communication PC of the drive regulator and are further processed (e.g. storage in the database, converted etc.). If diagnosis data are to be displayed on the user interface, the manager forwards the diagnosis data to the appropriate components in the Servlet container. There the data are prepared, so that they can be transferred by means of enquiry-based communication (polling) or by means of event-based communication (event channel) via the data remote connection to the Java Applets, which are embedded in the user interface.
FIGS. 6 and 7 show web-based user interfaces which graphically prepare the required diagnosis data for the user. Thus the diagnosis system according to the invention becomes an instrument which increases the machine availability and also makes complex appliances with a large number of drives manageable. Thus with the user interfaces of the type shown in FIGS. 7 and 8 , the machine control station can be supplied with data for the current machine status, or the production line can be provided with statistical data for machine availability and for maintenance cycles. But also the machine manufacturer or the drive supplier can thus have comfortable access to an appliance with a large number of technical-physical processes in order to afford rapid, efficient diagnosis and error correction during servicing. This is made possible by the user of modern web-based technologies or web-based user interfaces with their inherent versatility. Advantageously, the web interface can thus run on any client computer, independently of the respective client operating system. Installation of an user interface specific to the diagnosis system on the client computer node is no longer necessary. The web-based user interfaces are operable by the user in a customary and therefore easier manner due to the wide distribution by the Internet. The user interface can be adapted to the client's wishes at reasonable cost.
LIST OF REFERENCE NUMBERS
axle
electric motor
converter
process computer node
communication computer node
switch cabinet
SPS Control computer node.
While certain preferred embodiments of the present invention have been disclosed in detail, it is to be understood that various modifications may be adopted without departing from the spirit of the invention or scope of the following claims.
Key to the Drawings
FIG. 1
Antriebs . . . —drive system
Diagnoserechnerknoten—diagnosis computer node
Leitstand—control station
Diagnose—diagnosis
Router od.ISDN/Analog—router or ISDN/analogue
Ferndiagnose—remote diagnosis
FIG. 2
Diagnoserechnerknoten—diagnosis computer node
Diagnosestationen—diagnosis stations
FIG. 3
Prozessrechnerknoten—process computer node
Kommunikationsrechnerknoten—communication computer node
Diagnoserechnerknoten—diagnosis computer node
Konfiguration—configuration
Bedienung—operation
Diagnose—diagnosis
Client-Rechnerknoten—client computer node
FIG. 4
Zur Prozess . . . —To the process computer plane
Aufzeichnugs . . . —record manager
Anlagenmanager—appliance manager
Ereignis . . . —event manager
Benutzer . . . —user manager
Logging . . . —logging manager
Anlagenubersicht—appliance monitoring
Logbuch—logbook
Aufzeichnung—record
Visualisierung—visualisation
Inbetriebnahme . . . —installation+service
Wartung—maintenance
Ereignisanzeige—event display
Menu—menu
Menuhandler—menu handler
SOAP-Handler—SOAP handler
Zyklische Daten—cyclical data
Event+Heartbeat—event+heartbeat
Diagnose-Rechner . . . —diagnosis computer node
Firewall—firewall
Zu den . . . —to the client computer node
FIG. 5
Prozess . . . —process computer node
Kommunikations . . . —communication computer node
Proprietares protokoll—proprietary protocol
Informationsbroker—information broker
Parameter—parameters
Fehler U. Events—errors and events
Bedarfsdaten—demand data
Zyklische Sollwerte—cyclical setpoint values
Zeitzynchronisation—time synchronisation
Telnet-Zugang—Telnet access
Konfigurations . . . —configuration manager
Skripte—script
Logging Server—logging server
Diagnose-Netz—diagnosis network
Diagnose-Rechnerknoten—diagnosis computer node
Steuerungs-Netz—control network
Steuerung—control
FIG. 6
Gesamtubersicht—Total monitoring
Anlagenubersicht—appliance monitoring
(reading down the left-hand column)
Appliance status
Appliance monitoring
Logbook
Diagnosis
Record
Visualisation
Service
Parameter monitor
Maintenance
Regulator administration
Data records
Events
Secure drive
Firmware update
System functions
Settings
User management
BAUDIS NET setup
Documentation
Log off
FIG. 7
Antriebsystem—drive system
Column on left reads same as for FIG. 6
|
The invention relates to a computer network for configuration, installation, monitoring, error-diagnosis and/or analysis of several physical technical processes, in particular electrical drive processes, which occur under the control, regulation and/or monitoring of several process computer nodes, connected by means of at least one common communication system to at least one diagnosis computer node, in which one or several configuration, monitoring and diagnosis services and/or functions are implemented, provided for the processes and/or the process computer nodes and/or the data processing processes running therein, whereby the common communication system is achieved by means of the Ethernet, or a similar asynchronous and/or bus or communication system working with a stochastic access method.
| 7
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 07/676,271, filed Mar. 28, 1991, now abandoned, and is a continuation-in-part of application Ser. No. 333,763, filed Apr. 3, 1989, that has issued as U.S. Pat. No. 5,015,516, which in turn was a continuation of application Ser. No. 773,984, filed Sep. 9, 1985 and now abandoned, and application Ser. No. 362,344 filed Jun. 6, 1989.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention related to decorative inlaid sheet materials and the like. More particularly the invention is concerned with the use of organic and/or inorganic particles, particularly polyvinyl chloride (hereinafter "PVC") polymerization agglomerates, sometimes referred to herein as resinous particles, as decorative particles and their application on floor and wall covering substrates to produce realistic inlaid patterns, utilizing heretofore unobtainable design strategies and exhibiting superior properties.
The particles are spherical and/or essentially spherical (hereinafter "spheroidal") and are sometimes referred to hereinafter as "pearls." The particles are provided in one or more selectively applied matrix layers which, in some embodiments, overlay a printed design. When an underprinted design in used, a sufficient number of the particles are transparent and/or translucent so that the underprinted design is allowed to show through the matrix layer or layers and the design effects are created by the combination of the underprint and the selectively applied matrix layer or layers. When an underprinted design is not used, the design effects are created only by the selectively applied matrix layer or layers.
2. Description of Related Art
Sheet materials, in particular sheet vinyl flooring products, made with chips or particulate material, are commonly referred to as inlaids. These products and processes for the manufacture are well known in the floor covering business and originate back to the early linoleum times where through patterned floor coverings, based on linseed oil, cork dust and resins were developed by the industry. The process was later modified for vinyl.
Vinyl inlaid floor covering consists of coarse colored particles, such as chips or dry blends, which are "laid on" a substrate and thin sintered by heat, or "laid in" a transparent liquid or solid matrix and fused by heat. The chips are produced from pre-gelled or fused, spread, calendered or extruded compounds cut into geometrically regular profiles or ground int randomly shaped particles.
The dry blends are made by mixing fine PVC powder with plasticizer, stabilizer filler and color pigments and heating above the PVC compound's softening temperature. The small original particles "grow" and form a loose, porous, coarse, fluffy mass.
Currently, to produce realistic inlaid patterns for sheet vinyl, conventional manufacturing procedures distribute the coarse particles on the substrate in different steps with the help of area-complementary stencils, followed by topcoating with a clear wearlayer. This method is complicated and can only be used to produce large geometric patterns.
Inlaid floor coverings are normally characterized as those which maintain their decorative appearance as the surface is worn or abraded away. This characteristic makes such products particularly suitable for use in commercial area where significant wear is encountered.
Modern inlaids generally fall into two classifications: resilients and non-resilients. Resilients include a substantially continuous layer of foam and are usually made by incorporating solid particular material into a plastisol coating, followed by gelling and fusing. Non-resilients do not contain a foam layer and usually are made by sintering and/or calendering, or otherwise compacting, particulate material.
The non-resilient products commercially offered are those containing large (about 1/8 inch) square chips in a clear matrix and those containing small (about 0.004 inch) dry blend resin particles made by sintering and/or compacting normal dry blend resins. It is believed that the reason no products containing chips, granules, or particles of an intermediate particle size (e.g., ranging from about 0.004 inch to about 0.040 inch) are offered results from limitations inherent in current inlaid manufacturing technology, discussed more fully hereinafter.
While construction of inlaid products by compaction from discrete chips or particles (normally of different colors) offers distinct styling opportunities, a significant premium is paid in terms of expensive, cumbersome equipment. Furthermore, the nature of the process restricts the range of designs available. For example, in order to effect specific registered pattern definition, it is necessary to deposit chips of different colors in preselected areas on the sheet. This is difficult mechanically, and results in a slow cumbersome process which does not produce finely defined designs.
Some of the inherent difficulties in current production techniques for non-resilient inlaids have been minimized by use of increasingly sophisticated materials and design techniques, such as using fine particle size, dry blend resins, printing over the surface of the resulting inlaid product, optionally embossing, with and without application of a wearlayer. Unfortunately, whereas the use of the finer particle size preserves the specific characteristics of an inlaid product, i.e., the pattern does not change as the product wear through, overprinting the product, whether or not a wearlayer is applied, essentially engages this characteristic because wearing thorough the print layer essentially destroys the pattern. This eliminates the product from commercial, high-use environments and limits it utility principally to styling effect in the residential and related applications.
Resilient inlaids are usually made by embedding ground plastic particulate material in a plastisol coating. U.S. Pat. No. 4,212,691 exemplifies such products and methods for their manufacture. As taught in this patent, the thickness of the particles or the decorative chips or flakes is stated to be from about 3 mils to about 25 mils (e.g., see column 7, lines 62-64). However, it is the length of the particle, i.e., its largest dimension, rather than thickness that is observed when viewing the pattern. That dimension is stated to be from about 50 to 500 mils at column 8, lines 17-18. It is to be noted that the products disclosed all contain embedded chips or flakes ground from plastic sheet stock, even when chips or flakes from other stock materials are added (e..g, see column 8, lines 4 et seq). These chips or flakes characteristically have a high aspect ratio (i.e., length/thickness).
Thus, existing inlaid technology, although capable of producing commercially satisfactory inlaid products, has limitations and deficiencies. State of the art inlaid technology for "chip" products first grinds the chips from plastic sheets. This predefines the particle shape and is expensive.
Additionally, products formed by compacting or sintering PVC have always shown limited particle distinction due to process limitations and available particle sizes. The particles tend to lose their identity due to agglomeration or lumping caused by the sintering process.
A well known product having commercial applications is made by the Forbo Company in Gothenburg, Sweden. The product, called SMARAGD, is a vinyl sheet floor covering. SMARAGD is comprised of a solid PVC substrate reinforced with a non-woven glass fiber web. A foamable plastisol is applied in a random pattern followed by a clear vinyl coating containing evenly dispersed colored particles. The colored particles are generally low aspect ratio beds. Finally, an overcoating wearlayer of PVC is applied. The product does not embody a printed pattern or design.
When particles are admixed with a liquid plastisol composition prior to application to a surface, as in the product of SMARAGD, it is not possible to obtain a dense coating of the particles. This is due to viscosity and other interfering factors inherent in the plastisol. As a practical matter, therefore, the maximum density of the particles is limited to about 15-20% by volume. Total particle coverage in the final product is, therefore, effectively unattainable.
It has now been found in accordance with the present invention that durable inlaid floor coverings having unique design effects can be made by selectively applying one or more adhesive matrix layers to a substrate material which optionally may e printed with a uniform random print or a pattern or design. When the substrate is printed with a pattern or design, the matrix layer or layers may be selectively applied in register therewith. When a uniform random print or no underprint is used, design effects are created with the selectively applied matrix layer or layers.
SUMMARY OF THE INVENTION
In accordance with this invention, a decorative, inlaid floor or wall covering product is provided which incorporates as the essential elements thereof (i) an optional printed layer in the form of a uniform random print or a pattern or design overlaying a substrate, (ii) particles having an aspect ratio significantly lower than those currently employed in inlaids commercially offered in the United States and a particle size, preferably falling with the range of from about 0.004 inch to about 0.040 inch, (iii) one or more selectively applied adhesive layers in which said particles are embedded to make one or more adhesive matrix layers, and (iv) other optional elements such as a substrate coating or sealant and a wearlayer. Such optional elements will be discussed more fully hereinafter.
The particles employed in this invention have an aspect ratio of no greater than about 2:1 and, preferably, no greater than about 1.5:1. Particles having an aspect ratio of about 1:1 and, in particular, spheroidal particles, are especially preferred because of the excellent results achieved therewith, as discussed more fully hereinafter. The use of particles which are essentially as thick as they are long, i.e., having a low aspect ratio, provides a product that will not lose its decorative design effects due to wear in use, thus preserving the unique property which characterizes true inlaids.
In one embodiment, the use of printed patterns or designs which are visible beneath the selectively applied adhesive matrix layers containing the particles broadens the options available to the pattern designer. Exemplary is a decorative, inlaid floor or wall covering which comprises:
a) a substrate,
b) an optional latex layer overlaying and in contact with the substrate,
c) a printed layer, generally comprising a printable substrate coating or sealant onto which is printed a pattern of design in an ink suitable for floor or wall covering applications, overlaying and in contact with said substrate or optional latex layer, and
d) a selectively applied adhesive matrix layer, overlaying said printed layer in register with the pattern or design, and in contact therewith, in which are embedded low aspect ratio particles, said selectively applied adhesive matrix layer being sufficiently transparent or translucent to permit the underprint to show through. Effective transparency or translucency is achieved either 1) by using a sufficient proportion of transparent and/or translucent particles to opaque particles so that the underprint can shown through the particles themselves when a dense loading of particles used in accordance with the invention which particles otherwise would effectively prevent the underprint from showing through interstices between the particles or 2) when a less dense loading of particles is used, the underprint can show through interstices between the particles and through any translucent and/or transparent particles which might be used.
Such product provides options for a wide variety of design strategies heretofore unobtainable with state-of-the-art sheet vinyl technology and constitutes a preferred embodiment of this invention.
The inlaid products of this invention offer unique design advantages. Further, cost advantages can be realized by utilizing raw materials which are believed to be unique to inlaid manufacture. For example, certain of the novel products of the invention incorporate an adhesive matrix consisting essentially of a plastisol layer containing transparent and/or translucent and colored spheroidal particles, which, preferably, range in size from about 0.004 inches to about 0.040 inches. When this matrix is applied over a printed pattern, a unique visual effect is produced.
Such particles can be made in uniform controlled sizes by employing technology described in U.S. Pat. No. 3,856,900, the entire contents of which are incorporated herein by reference. Alternatively, special large particle size dry blend resinous particles, either screened to the desired size ranges of this invention from oversized material obtained from normal production variations, or specially made particles in the desired size range, can be utilized.
Another, embodiment of this invention is a decorative, inlaid floor covering which comprises in the following order:
a) a non-asbestos felt sheet substrate,
b) an optional latex layer which can optionally be tinted or dyed,
c) optionally a gelled, optionally foamed, printable, plastisol coating over said substrate which can optionally be tinted or dyed,
d) optionally, one or more inks applied to the surface of the substrate, latex layer or plastisol coating either in a uniform random print or in a pattern or design,
e) multiple adhesive matrix layers, overlaying said substrate, latex layer, plastisol coating, or print layer, and in contact therewith, in each of which are embedded discrete spherical and essentially spherical particles wherein the adhesive used to make one, some, or all of the selectively applied adhesive matrix layers is transparent or optionally contains a colorant or dye which makes it translucent; the compositions, sizes and colors of the particles embedded in each adhesive matrix layer are the same or different, and for each adhesive matrix layer, either 1) a dense loading or particles is used wherein a sufficient proportion of transparent and/or translucent particles to opaque particles are present so that the optional underprint or unprinted undercoating or substrate can show through the particles themselves and essentially not show through interstices between the particles; 2) a less dense loading of particles is used so that the optional underprint or unprinted undercoating or substrate can show through interstices between the particles and through any translucent or transparent particles which might be used; or 3) a dense loading of particles is used which effectively prevent the optional underprint or unprinted undercoating or substrate from showing through; provided that the particle loading and transparency/translucency features of 1), 2) and 3) above can be the same or different for each adhesive matrix layer and said adhesive matrix layers can be in or out of register with each other and/or any underprinted pattern or design, and
f) optionally, a fused, transparent, plastisol wearlayer as a top coat
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The product is comprised of a base supporting material, which, optionally, may be precoated with a latex and/or a plastisol to enhance printability, an optional print layer offering decoration, and one or more selectively applied adhesive matrix layers containing spheroidal particles, wherein the particles can be transparent, translucent and/or opaque. In one embodiment, the resultant product has an additional coating on its top surface to enhance surface properties, such as gloss and the like, and insure there is no residual porosity resulting from the process of embedding the particulates into the adhesive matrix layer.
The incorporation of particulate materials of such size and shape, and at the loadings herein described, provides the retention of pattern as the product wears through, which is characteristic of inlaid products. The incorporation of transparent and/or translucent particles allowing the underprint to show through in some embodiments, provides an additional dimension in design capability. The combination of a transparent and/or translucent selectively applied adhesive matrix loaded with transparent and/or translucent and/or pigmented particulate material and the use of rotogravure or other forms of print offering fine registered detail and definition, provided a product which is believed to be unique and a significant advance in the art.
One of the advantages of this invention is that it employs ingredients and processing technology well known to those skilled in the art. Also, by employing a fluid plastisol as the matrix material binding the particles together, the product can be manufactured without the need for the high pressures or temperatures characteristic of the calendering or agglomeration steps of the prior art processes. This processing characteristic also distinguishes the subject process from those of the prior art which employ only dry blend resins, which are agglomerated through heat sintering.
Substrate
The substrate is a relatively flat fibrous or non-fibrous backing sheet material, such as a fibrous, felted or matted, relatively flat sheet of overlapping, intersecting fibers, usually of non-asbestos origin. The substrate can, if desired, be asbestos or non-asbestos felts or papers, woven or non-woven; knitted or otherwise fabricated textile material or fabrics comprised of cellulose, glass, natural or synthetic organic fibers, or natural or synthetic inorganic fibers, or supported or non-supported webs or sheets made therefrom or filled or unfilled thermoplastic or thermoset polymeric materials. These and other substrate or base materials are well known in the art and need not be further detailed here.
Substrate Coating
The substrate or base material optionally can be coated with carriers for smoke suppressants and/or flame retardants and/or to improve the print quality of the substrate. Such coatings can be plastisols, organosols, lacquers, filled or unfilled latex coatings, and/or other coatings conventionally employed as preprint sealants in the manufacture of floor or wall covering products.
The optional latex layer, is a smooth coating which may be colored or not colored, filled or unfilled. In a preferred embodiment, the latex is tinted with a color which is compatible with the colors of any printed pattern or design and/or the particles used to create design effects. Most preferably, the latex layer is tinted with a color which is the average of the colors of the overall product design. To one skilled in the art, the average color means the color perceived when one looks at a surface from a distance of more than about 5 feet. Also, the latex layer is preferably used as a carrier for flame retardant and smoke suppressant compositions.
The latex layer is substantially uniformly coated over the substrate to a thickness from about 1 to about 4 mils, preferably from about 1.5 to about 2.5 mils. Conventional means for coating the substrate with the latex layer can be used and are not critical to the invention. Such means include an air knife, a rotogravure roller with a plain etch or knurled roll, rotary screen, drawdown bar, or wire wound bar (wherein the grooves provided by the wires assist in metering the flow of the latex). Following application of the latex layer, it is dried prior to further processing. This can e accomplished in a hot air oven at a temperature from about 2252 to about 350° F. preferably from about 275° to about 300° F., for from about 4 minutes to about 30 seconds, preferably from about 2 minutes to about 30 seconds. Lower temperature and longer times may be used as long as conditions are adequate to remove water. Higher temperatures and shorter times may also be used with sufficient air velocity as long as the latex layer is not caused to bubble. The latex layer can be made from any commonly available latex formulation as long as it is compatible with the substrate and the layer overlaying the latex layer. The latex composition preferably should have minimal smoke generating properties and should be moisture resistant and have good aging properties. It should also have good adhesion compatibility with the layer overlaying it. Suitable latex include crosslinkable ethylene vinyl acetate latexes, crosslinkable acrylic latexes, ethylene vinyl chloride emulsions, PVC and polyvinyl acetate latexes, copolymer latexes, and butadiene-acrylonitrile latexes.
When the latex layer is tinted, a color pigment may be used which is chemically compatible with the latex composition and the other components of the product. Suitable color pigments include inorganic or mineral pigments such as titanium dioxide, chromium trioxide, cadmium sulfide, iron oxide, carbon black and the like.
A plastisol layer can be used instead of the latex layer or can be applied over the latex layer. This layer can also be tinted if desired in the same manner as explained above with reference to the latex layer.
As used herein, the term "plastisol" is intended to cover a relatively high molecular weight polyvinyl chloride resin dispersed in one or more plasticizers. The plastisol upon heating or curing forms a tough plasticized solid. For purposes of the present invention, plastisol compositions are intended to include organosols, which are similar dispersed polyvinyl chloride resin materials that, in addition, contain one or more volatile liquid that are driven off upon heating.
Those skilled in the art will appreciate that, in addition to the basic resin constituents, other commonly employed constituents can be present in the plastisol compositions in minor proportions. Such other constituents commonly include heat and light stabilizers, viscosity depressants, and/or pigments or dyes, the latter in order to contribute color to the polyvinyl chloride resin.
Typically when a plastisol substrate coating is employed in the products of this invention, it is a resinous polymer composition, preferably, a polyvinyl chloride plastisol which is substantially uniformly applied to the substrate surface, for example, by means of a conventional reverse roll coater or wire wound bar, e.g., a Meyer Rod Coater. The particular means for applying the plastisol coating to the underlying surface does not relate to the essence of the invention and any suitable coating means can be employed. Exemplary of other coating means are a knife-over roll coater, rotary screen, direct roll coater and the like.
The thickness of the resinous polymer composition or plastisol, as it is applied to the underlying surface, is substantially uniform, and is in the range from about 1.5 mils to about 30 mils, 1.5 mils to about 12 mils being especially preferred.
Although the preferred and typical substrate coating is a polyvinyl chloride homopolymer resin, other vinyl chloride resins can be employed. Exemplary are a vinyl chloride-vinyl acetate copolymer, a vinyl chloride-vinylidene chloride copolymer and copolymers of vinyl chloride with other vinyl esters, such as, vinyl butyrate, vinyl propionate, and alkyl substituted vinyl esters, wherein the alkyl moiety preferably is lower alkyl containing between about 1-4 carbons. Other suitable synthetic resins such as polystyrene, substituted polystyrene, preferably wherein the substituents are selected from the group consisting of alkyl (C 1 -C 10 , preferably C 1 -C 4 ), aryl (preferably, C 6 -C 14 ), polyolefins such as polyethylene and polypropylene, acrylates and methacrylates, polyamides, polyesters, and any other natural or synthetic resin capable of being applied to the substrate or base coatings of this invention to provide a smooth and uniform surface and/or to improve the print quality of the substrate or base coating surface, are also applicable; provided such resin is otherwise compatible with the overall product composition and, therefore, within the principles of this invention. Thus, it is not essential that a plastisol always be used. Organosols and aqueous latices (aquasols and hydrsols) are also of use, employing as the dispersing or suspending media, organic solvents and water, respectively, rather than plasticizers, as in the case of a plastisol.
Where the preferred plastisol is employed, typical of the plasticizers which can be used are dibutyl sebacate, butyl benzyl sebacate, dibenzyl sebacate, dioctyl adipate, didecyl adipate, dibutyl phthalate, dioctyl phthalate, dibutoxy ethyl phthalate, butyl benzyl phthalate, dibenzyl phthalate, di(2-ethylhexyl) phthalate, alkyl or aryl modified phthalate esters, alkyl, aryl, or alkylaryl hydrocarbons, tricresyl phosphate, octyl diphenyl phosphate, dipropylene glycol dibenzoate, dibasic acid glycol esters, and the like. Other constituents of the resinous substrate coating can include a blowing or foaming agent such as azodicarbonamide (if a blowing or foaming procedure is desired), conventional stabilizers/accelerators, initiators, catalysts, etc., such as zinc oleate, dibasic lead phosphite, etc., conventional heat or light stabilizers, such as metallic soaps, etc., ultraviolet absorbers, colorants, dyes or pigments, notably, titanium dioxide, solvents and diluents, such as methyl ethyl ketone, methyl isobutyl ketone, dodecyl benzene, etc., fillers, such as clay, limestone, etc., viscosity modifiers, antioxidants, bacteriostats and bactericides, and the like.
After the plastisol layer is applied to the substrate, the combination is heated for a period of time and at a temperature sufficient to gel the plastic composition, but not sufficient to activate or to decompose any blowing or foaming agent which may be present. This can e done in an oven or on a heated chrome drum. If an oven is used for the gelling step, a residence time in the oven from about 0.5 minutes to about 3.5 minutes at an oven temperature from about 320° F., to about 250° F., will give good results. If a chrome drum is used, a dwell time on the drum of from about 8 seconds to about 30 seconds at a drum temperature of from about 310° F. to about 240° F. will give good results. The higher temperatures are used with shorter residence or dwell times and lower temperatures with longer times. The layer is then cooled to form a pre-gel which provides a surface suitable for printing. Cooling is generally accomplished by contacting the surface of the foamable, gelled plastic layer (and sometimes the underside of the substrate) with one or more cooling drums. Ambient or chilled water is circulated through the drums. Cooling may be enhanced with the use of fans or blowers.
Optional Print Layer
The optional print layer is applied in a uniform random print or in the form of a pattern or design and can be applied directly to the substrate. If latex and/or plastisol layers are used, the print layer will be applied to the uppermost such layer. The print layer can be comprised of one or more layers of ink.
Suitable printing inks include those normally used in the manufacture of floor covering, preferably resilient floor covering. These include plastisol solvent based systems and water based systems. Such system can include a chemical suppressant in those cases where the substrate in which the ink is to be applied is a foamable plastisol or organosol. Such suppressants are well known in the art (e.g., see U.S. Pat. No. 3,293,094). Ultraviolet curable printing inks can also be used.
The printing ink may be pigmented or non-pigmented and may include organic pigments or inorganic pigment particles such as titanium dioxide, chromium trioxide, cadmium sulfide, iron oxide, carbon black, mica and the like. Decorative reflective particles may also be included as part of the printing ink composition or may be separately applied either randomly or by selective deposition in the form of a pattern or design.
Printing can be effected by rotary screen, rotogravure, flexigraphic, screen printing, or other printing techniques conventionally employed in making floor or wall covering products.
Selectively Applied Adhesive Layer or Layers
The adhesive layer or layers are normally a plastisol or organosol additionally containing a plasticizer system, associated diluents, viscosity control aids and stabilizers. Those discussed above are exemplary. The adhesive layer or layers also can include a chemical suppressant in those cases where the substrate is a foamable plastisol or organosol. The chemical suppressants, which are well known in the art, can be used whether or not the substrate is printed.
Although other homopolymers and copolymers of vinyl chloride, (i.e., vinyl resins other than a plastisol or organosol) such as those discussed above, can also be employed, as a practical matter, current economics dictate the use of polyvinyl chloride plastisols of the type set forth in the examples hereinafter.
Each adhesive layer is selectively applied using a rotary screen, flat bed screen or other suitable techniques. After one adhesive layer is applied, particles are randomly applied over the surface of the layer and embedded into it, and it is gelled to make an adhesive matrix layer as described below. Excess particles are removed by vacuuming or other suitable means either prior to or following the embedding step. Such excess particles may include those which are applied over the spaces which are not coated with the adhesive and/or those which do not adhere to or are not embedded in the adhesive. After gelling, a subsequent adhesive layer can be applied followed by the same sequence of applying particles, removing excess particles, embedding particles and gelling. This series of steps is repeated for each successive, selectively applied, adhesive matrix layer. In an alternative embodiment, some or all of the selectively applied adhesive matrix layers can be made by admixing particles with the adhesive before it is applied, followed by gelling. As explained above, when multiple adhesive matrix layers are used they can optionally be in register with one another and/or with any underprinted pattern or design.
The thickness of each selectively applied adhesive layer as it is applied to the substrate, latex layer, plastisol coating or print layer is substantially uniform, and is in the range of about 2 mils to about 30 mils, 5 mils to about 20 mils being especially preferred. The layer can be thinner or thicker as may be required by the particular product application, as long as it is thick enough to accommodate the layer of particles which subsequently will be embedded into it.
Particles
The particles of this invention are spherical or essentially spherical, (sometimes referred to herein as "spheroidal") and have an aspect ratio no greater than about 2:1, and preferably no greater than about 1.5:1, which is required to obtain the desirable design effect this invention is capable of providing.
The particles can be comprised of various homogeneous or heterogeneous organic or inorganic materials or mixtures thereof and can be transparent, translucent or opaque. Suitable particles can be made from any one, or a combination or mixture of mica, ceramics, metals, rubbers, and polymeric and resinous compositions such as acrylics, plastisols, polyamides, polyolefins, polycarbonates, polyvinyl chloride and copolymers thereof, and polyesters. Particles made from resinous compositions, i.e., resinous particles, may include compounded materials having fillers such as calcium carbonate. Each translucent or opaque particle can contain its own individual colorant, dye or pigment.
It is preferred to employ discrete spheroidal particles for enhanced visual effect of depth and improved wear characteristics. Illustrative of those spheroidal particles are the particles and the methods for their manufacture taught in the U.S. Pat. No. 3,856,900. This procedure is particularly convenient for the production of relatively small plastisol beads or "pearls" having a particle size of generally about 0.020 inch or smaller.
The particles can be obtained by screening the oversized particles from normal suspension grade resin production or by making special particle sizes, for example, in accordance with U.S. Pat. No. 3,856,900. Particles can also be produced from other processed compounds such as extruded or calendered PVC which is subjected to a grinding process to produce particles having suitable sizes and aspect ratios. Particles in the preferred size range of from about 0.004 to about 0.040 inch are particularly useful for achieving certain desirable design effects.
A preferred method of making the spheroidal resinous particles is to dry blend PVC powder by agitating it in a container provided with a propeller agitator, such as a Henschel Mixer, at a speed of up to about 3,000 r.p.m., until it reaches a temperature of about 160° F. The speed is then lowered to about 500 r.p.m. during addition of the PVC plasticizer, stabilizer and optionally, a color dispersion. The agitator speed is then increased to about 3,000 r.p.m. until the temperature of the mixture reaches about 230° F. Then the agitator speed is lowered to allow to cooling to about 100° F. and the spheroidal resinous particles thereby produced are discharged.
Other methods of making the spheroidal resinous particles include ribbon blending or paddle blending to dry blend the PVC powder in a manner similar to that described above.
It has been found that the size of the particles employed in carrying out this invention have a pronounced effect on the results obtained. Use of relatively small particles, e.g., ranging from about 150 microns (100 mesh) to about 600 microns (30 mesh) are most advantageous in producing the desired design effects. Particles, especially spheroidal particles, averaging about 400-600 microns (by microscopic observation) are especially preferred.
When a sufficient loading of particles is used to essentially completely cover the underlying material and the particles are resinous, they are deposited at a minimum density of about 0.3 pounds per square yard, with from about 0.4 to about 0.8 pounds per square yard being preferred. A density from about 0.55 to about 0.65 pounds per square yard is most preferred. When this embodiment is used in a product having an underprint, one must consider the ratio of transparent to colored particles which will determine the visibility of the printed pattern underneath the resulting adhesive matrix. Generally, 75% or less, and preferably 25-55% transparent and/or translucent to colored particles loading is preferred. The amount actually used will, of course, depend upon the type of end-use application and design effect desired. Good results have been achieved in the range of 35-45% transparent and/or translucent to colored particle loading.
The particles can be applied over each selectively applied adhesive layer, making a layered intermediate product, following the methods disclosed in U.S. patent application Ser. No. 362,344, filed Jun. 6, 1989, one of the parents of the present application. Known apparatus such as a magnetic vibrating pan or trough or a VILLARS powder coater made by Villars Maschinenbau, Muenchwilen, Switzerland can be used. A particularly preferred means is to use a dry material dispensing machine of the type disclosed and claimed in U.S. Pat. Nos. 3,070,264 and 3,073,607 to Christy. Machines of this type are available from the Christy Machine Company, P.O. Box 32, Fremont, Ohio. The Christy "COAT-O-MATIC" (also called the "SIEVE-O-DUSTER") is particularly preferred.
The COAT-O-MATIC is normally used by the food industry to apply things like poppy seeds on rolls, sugar on cookies, and the like. However, it can easily be modified by one skilled in the art to uniformly deposit spheroidal particles in the production of floor coverings. The modifications are required to improve the uniformity of application of the spheroidal particles. In particular, the ability to make adjustments must be refined and vibrations and deflections must be reduced.
We bound that the following modifications to the COAT-O-MATRIC made it suitable for depositing particles in accordance with this invention:
1. A larger diameter, knurled dispensing roll is used to reduce deflection and eliminate wobble which otherwise causes recurring bands of light and heavy application of the spheroidal particles. The dispensing roll should have a total indicated run-out of less than or equal to about 0.010 inch, deflection due to weight of less than or equal to about 0.030 inch and a balance of less than or equal to about 2 inch ounces. The rigidity of the dispensing roll should be sufficient to prevent "galloping" (where the roll remains deflected in one orientation; thereby causing it to rotate like a banana).
2. An adjustable rubber applicator blade mounted on a reinforced holder is used to provide refined adjustment of the pressure for uniform application across the width of the machine.
3. Adjustment means are added to the brush holder to provide adjustment of pressure on the brush across the width of the machine.
4. Reinforcement of the hopper is required to limit deflections along its length. Deflections less than or equal to about 0.030 inch being preferred.
The foregoing modifications can be made by various means by those skilled in the art consistent with the objectives set fort above and elsewhere in this specification.
The density of particles deposited using the modified COAT-O-MATIC can be adjusted for a given line speed by varying the speed of rotation of the dispensing roll.
The deposited particles are embedded in each adhesive layer as described below.
Embedding the Spheroidal Particles in the Adhesive Layer and Gelling the Adhesive Layer
When the spheroidal particles are embedded in the adhesive layer, the adhesive layer is simultaneously gelled, thereby forming a matrix layer of spheroidal particles in a gelled adhesive. This can be achieved by heating the intermediate product in an oven at a temperature from about 260° to about 350° F., preferably from about 275° to about 300° F., for from about 4 minutes to about 1 minute, preferably from about 2.5 to about 1.5 minutes. In a preferred embodiment of the invention, however, embedding and gelling are achieved by using a hot chrome drum provided with a pressure belt as described in U.S. Pat. No. 4,794,020 to Lussi, et al. The drum is heated to a temperature from about 260° to about 350° F., preferably from about 275° to about 320° F. The intermediate product is maintained in contact with the drum for from about 3 minutes to about 10 seconds, preferably from about 60 to about 15 seconds. In another embodiment, supplementary heat can be used, e.g., infrared or the like, prior to heating in an oven or on a drum, thereby shortening the heating times set forth above.
Gelling conditions will also vary with the molecular weighty of the resin and other properties such as the solvating properties of the resin and plasticizer. Those skilled in the art will recognize the importance of applying sufficient heat to gel each adhesive layer, while avoiding the excessive heat which could damage the product.
Plastisol Wearlayer
An essentially smooth coating of plastisol can optionally be applied over the selectively applied adhesive matrix layer or layers. This coating is substantially uniformly applied to the underlying surface by conventional means such as a knife-over roll coater, direct roll coater, rotary screen, draw down bar, reverse roll coater or wire wound bar. The particular means for applying the coating does not relate to the essence of the invention and any suitable coating means can be employed. The smooth coating of plastisol can then be gelled in an oven or with a hot chrome drum under the same conditions as described above with reference to gelling the adhesive layer. A plastisol wearlayer is thereby secured to the underlying surface. This process can be repeated to provide additional wearlayer as desired. The plastisol wearlayers can have a thickness of from about 2 to about 100 mils, and preferably have a thickness of from about 10 to about 40 mils.
In one embodiment, two clear plastisol wearlayers are used. After the first wearlayer is applied and gelled using a hot chrome drum, it is embossed at a temperature which will allow the embossing to be reversed upon the subsequent application of heat. The a second plastisol layer is applied followed by using in an oven. This causes the stressed created by embossing in the first wearlayer to relax, thereby causing a reverse embossing effect in the second wearlayer. A reverse embossed wearlayer is amenable to easy cleaning.
Urethane Wearlayer
Polyurethanes can also be used for wearlayers in accordance with the invention. They can be used instead of plastisol wearlayers or in addition to them. A smooth coating of polyurethane can be applied using the same means as those used to apply smooth coatings of latex. Polyurethane can also be applied by laminating it onto another substrate and applying it to a surface with an adhesive.
Depending upon the chemistry of the polyurethane, the polyurethane layer can be cured by heat, chemical reaction, ultraviolet light or electron beam radiation. A preferred means is high energy ultraviolet light.
The cured polyurethane layer can be from about 0.1 to about 10 mils thick and is preferably from about 0.25 to about 4 mils thick. Additional layers of polyurethane can be used if desired. In a preferred embodiment of the invention, one polyurethane wearlayer is applied over the reverse embossed plastisol wearlayer described above.
The composition of the polyurethane wearlayer can include any number of commercially available formulations as long as they are compatible with the other components of the floor covering of the invention and the objectives of the invention as set forth in this specification. Common urethane oligomers include polyester, polyether, epoxy-acrylic and polyamides. The most preferred types ar urethane-acrylo based oligomers diluted with acrylic monomers and containing photoinitiators to provide the means for radiation curing. This is considered to be a thermoset polymer system in that the oligomer are unsaturated resins with functional groups that interact with each other and with the monomers providing chemical linkages during the polymerization process. The reactions are terminated by photopolymerizable groups made available on the interacting components. The chemical linkages that are created between groups and polymer chains characterize the radiation cured urethanes as thermoset materials as opposed to thermoplastic polymers in which functional groups either do not exist or do not interact. The thermoset properties are unique in that urethane films will not remelt when heated and in general exhibit a harder, more inert character than thermoplastic polymers. Normally, they will provide better scuff resistance and retained gloss when compared with the common thermoplastic PVC alternative.
Flame Retardant and Smoke Suppressants
Conventional flame retardants and smoke suppressants which are compatible with the various materials used in accordance with the invention can be added at any stage of the process. They can be impregnated into the substrate, admixed with the latex layer, the plastisol layer and/or the adhesive layer, and/or admixed with any of the plastisol and/or urethane wearlayers. Spheroidal resinous particles and other types of spheroidal particles containing such compositions can also be manufactured for use in accordance with the invention. In the preferred embodiment of the invention, effective quantities of flame retardants and smoke suppressants are admixed with the latex layer and/or one or more of the plastisol layers.
Flame retardants and smoke inhibitors which can be used in accordance with the invention include aluminum trihydrate, zinc borate, magnesium hydroxide, antimony trioxide, phosphates and other compounds and compositions which are compatible with the various constituents of the products of the present invention. They are added in effective amounts which will be apparent to those skilled in the art based on manufacturers specifications and code requirements.
Static Dissipation
In order to adjust the electrical properties of the product of the invention, the formulation of the coating used in each layer and the composition of the substrate may need to be modified. The objective is to lower the resistance (raise the conductivity) of the product. Standards and testing procedures for surface to surface and surface to ground resistance for floor coverings are well known in the industry. A preferred range for the products of the invention is 1,000,000 to 1,000,000,000 ohms as tested per ASTM F-150-72 (standard test method for electrical resistance of conductive floor covering). This test is conducted at 500 volts direct current and 50% relative humidity.
In the preferred embodiment of the invention, carbon fibers are incorporated into the substrate to lower is resistance. Antistatic agents that can be added to the latex layer, adhesive layer and wearlayers are commercially available and known in the art. Suitable antistatic agents include Nopcostate HS, an ethoxylated composition from Diamond Shamrock and Tebestat IK 12, a nonionic substituted polyether from Dr. Th. Boehme KG, Chem. Fabric GMBH & CO., 8192 Geretsried 1, German. The particular compositions used are not critical as long as they are compatible with the other components present in the durable inlaid floor coverings of the invention. The antistatic agents may be added in various amounts as will be apparent to those skilled in the art depending on recommendations of the manufacturers of said compositions and the desired specifications for the floor covering product. A polyurethane wearlayer is not used in the preferred static-dissipative embodiment of the invention.
EXAMPLES
In the following examples all parts and percentages are by weight.
EXAMPLE 1
Floor Covering Printed With Simulated Brick Pattern Suitable for Commercial Uses
A floor covering substrate sheet of conventional type nonasbestos felt (Tarkett Inc., Whitehall, Pa.), approximately 32 mils thick, is bar coated (wire wound bar) with approximately 3 mils of a layer of white printable plastisol, the composition of which is as follows:
______________________________________ Parts by Weight______________________________________PVC dispersion resin: k value 62 70(Occidental FOC 605)PVC extender resin: k value 60 30(PLIOVIC M-50)Di(2-ethylhexyl) phthalate 30Butyl benzyl phthalate 30Titanium dioxide 5Crystalline calcium carbonate 80Barium-zinc type stabilizer 3(SYNPRON 1492)______________________________________
After gelling against a heated chromium drum at 300° F., the resulting smooth surface is gravure printed on a flat print press using solvent based inks of the following composition:
______________________________________ Parts by Weight______________________________________PVC-polyvinyl acetate copolymer 100Pigments 180(A purchased blend of colors selectedfrom red iron oxide, yellow iron oxide,chrome yellow, molybdate orange, carbonblack, titanium dioxide, quinanthronered, phthallo blue and phthallo green.)Solvent 600(Methyl ethyl ketone/xylene)Dispersion aid 2______________________________________
After drying in warm air at about 140° F., an adhesive layer about 20 mils thick is selectively applied in register with the simulated bricks by a rotary screen and an excess of premixed plastisol pearls (produced in Example 3 and having the composition set forth hereinafter), about half of which are transparent and the remainder colored with about 50-50 blend of red brick color and white color, are evenly distributed over the surface from a vibrating pan SYNTRON vibrator manufactured by FMC Corp.) to a density of about 0.60 pounds per square yard. The composition of the adhesive mix is:
______________________________________ Parts by Weight______________________________________PVC dispersion resin: k value 68 70(Occidental OXY 68 HC)PVC extender resin: k value 60 30(PLIOVIC M-50)Butyl benzyl phthalate 25Di-isononyl phthalate 25Stabilizer, barium-zinc type 4(SYNPRON 1492)______________________________________
The composition of the pearl particles is:
______________________________________ Parts by Weight Colored Transparent______________________________________Suspension grade PVC resin: k value 65 100 100(PEVIKON S658 GK)Butyl benzyl phthalate 40 40Stabilizer, barium-zinc type 4 4(SYNPRON 1665)Titanium dioxide 5 --Conventional Color-pigment 5 --______________________________________
The PEVIKON S658 GK resin has an aspect ratio of about 1 (the particle are round) and the particle size is found by microscopic observation to average about 400-600 microns (approximately 30-40 mesh). Screen analysis is as follows:
______________________________________Mesh % Retained______________________________________30 (500-800 microns) 1040 (400-600 microns) 6060 (250-400 microns) 29Thru 100 mesh 1______________________________________
The excess pearls, which are not wetted by the adhesive coating and embedded therein are vacuumed away. The resultant selectively applied grainy matrix is then gelled by contacting the coated side against a heated chromium drum (350° F.) and smoothed between a rubber pressure roller and the drum surface. The thickness of the matrix containing the adhesive coat (12 mils) and the embedded pearls (approximately 23 mils) is 25-30 mils.
Another adhesive layer is selectively applied by a rotary screen in register with the grouting between the simulated bricks and an excess of premixed plastisol pearls of the same type as used above, about half of which are transparent and the remainder colored with about a 50-50 blend of gray color and white color, are evenly distributed over the surface from the vibrating pan to a density of about 0.60 pounds per square yard of coated area. Excess pearls are removed and the selectively applied grainy matrix is gelled as above.
The surface of the matrix was then bar coated using a drawdown bar with a transparent plastisol wearlayer having the following composition:
______________________________________ Parts by Weight______________________________________Dispersion grade PVC, k value 68 100(Occidental OXY 68 HC)Monsanto SANITIZER S-377 plasticizer 56Stabilizer, barium-zinc type 5(SYNPRON 1665)Epoxidized soybean oil 5Kerosene 2______________________________________
The wearlayer is fused in a hot air oven at 380° F. for 3.5 minutes and then embossed between a cooled embossing roll and a rubber pressure roll. The resultant wearlayer has a thickness of about 15 mils.
EXAMPLE 2
Commercial Floor Covering With Registered Printed and Embossed Patterns (Chemically Embossed)
A floor covering substrate sheet of conventional type non-asbestos felt (Tarkett Inc., Whitehall, Pa.) approximately 32 mils thick is coated with a foamable plastisol the composition of which was as follows:
______________________________________ Parts by Weight______________________________________PVC dispersion resin: k value 62 70(Occidental FPC 605)PVC extender resin: k value 60 30(PLIOVIC M-50)Di(2-ethylhexyl) phthalate 28Butyl benzyl phthalate 15Texanol isobutyrate (TXIB) 15Titanium dioxide 10Azodicarbonamide 2.5Kerosene 4Zinc oxide 1.5______________________________________
The coated substrate is then pregelled in a hot oven at 275° F. for 2.5 minutes. The surface is then gravure printed on a flat bed press using solvent based PVC and PVC-polyvinyl acetate copolymer inks having the same composition as those of Example 1 except that the inks used to cover the plate printing the valley areas of the pattern (i.e., the grouts) contain benzotriazole, a chemical suppressant, to inhibit in these selected area the expansion of the foamable plastisol.
After drying the print, selectively applied adhesive matrix layers having the same compositions as those of Example 1 are applied coated and embedded with pearls and gelled in the same manner as those of Example 1. The thickness of the resulting matrixes containing the pearls embedded in the adhesive are each about 25-30 mils. Approximately 10 mils of a transparent wearlayer having the same composition as that of Example 1 was applied with a drawdown bar. The resulting product was then fused and expanded (i.e., foamed) in a hot air oven at 380° F. for 3 minutes.
The floor covering produced shows a relief structure (embossing) in register with the printed areas. The decorative inlaid product thereby produced has an overall thickness of about 86 mils and exhibits excellent wear and design characteristics.
EXAMPLE 3
The plastisol spherical "pearls" used in the foregoing examples are prepared using the following formulations:
______________________________________ Parts by Weight Colored Transparent______________________________________Suspension grade PVC resin, course: 100 100k value 65 (PEVIKON S658 GK)Butyl benzyl phthalate 40 40Stabilizer, barium-zinc type 4 4(SYNPRON 1665)Titanium dioxide 5 --Color-pigment 5 --______________________________________
In preparing the colored and transparent plastisol composition, the PVC resin (at 70° F.) is charged to a high intensity mixer running at 3500 revolutions per minutes (r.p.m.) and mixed until the batch temperature reached 160° F. (about 10 minutes). The speed of the mixer is then reduced to 500 r.p.m and the pigment pastes, plasticizer and stabilizer are added slowly over a period of about 5 minutes. The speed is then increased to 2000-3000 r.p.m. and the material mixed until the batch temperature reaches 260° F. (approximately 15 minutes additional). The speed is then reduced to 500 r.p.m. and the material is mixed until the batch temperature is cooled to 70°-90° F. (about 30 additional minutes).
The pearls produced are essentially spherical, dry and free running, do not exceed 0.040 inches in diameter and generally have a particle size distribution range of 0.004 to 0.030 inches.
The following table summarizes the process parameters: Equipment: High intensity mixer 2.6 gal. volume 3 lbs. loading
______________________________________Elapsed Time Temperature SpeedMinutes Degrees F. r.p.m.______________________________________ 0 70 350010 160 500 pigments, plasticizer and stabilizer added15 260 2000-300030 500 cooling60 70 --______________________________________
Examples 1 and 2 demonstrate decorative, inlaid floor coverings which constitute preferred embodiments of this invention and which comprise:
a) a substrate sheet of conventional type nonasbestos belt,
b) a gelled, thin, white, or tinted, printable plastisol coating either non-foamable or foamable over said substrate, prepared from effective amounts of a formulation comprising:
a PVC dispersion resin, preferably having a k value of about 62,
a PVC extender resin, preferably having a k value of about 60,
a plasticizer, preferably a phthalate such as di(2-ethylhexyl) phthalate or butyl benzyl phthalate,
optionally, a foaming agent,
a pigment, preferably titanium dioxide,
a crystalline calcium carbonate, and
a barium-zinc type stabilizer
c) a print layer of one or more inks made from effective amounts of a formulation comprising:
a PVC and PVC-PVAc resin copolymer blend,
one or more pigments,
a solvent, preferably consisting essentially of methyl ethyl ketone and xylene, and
a dispersion aid;
d) gelled, selectively applied adhesive layers made from effective amounts of formulations comprising:
a PVC dispersion resin, preferably having a k value of about 68,
a PVC extender resin, preferably having a k value of about 60,
a plasticizer, preferably butyl benzyl phthalate or di-isononyl phthalate, and
a barium-zinc type stabilizer, and
e) a mixture of gelled, transparent and colored pearls, wherein the pearls are about 50% transparent and about 50% colored, evenly and densely distributed over the surface, prepared from effective amounts of a formulation comprising:
a PVC suspension resin, preferably coarse and having a k value of about 65,
a plasticizer, preferably butyl benzyl phthalate,
a barium-zinc stabilizer, and, optionally,
a pigment or a color selected from the group consisting of red iron oxide, yellow iron oxide, chrome yellow, molybdate orange, carbon black, titanium oxide, quinanthrone red, phthallo blue and phthallo green.
Although the foregoing discussion describes this invention in terms of floor or wall covering products, this invention is intended to encompass any covering including, but not necessarily limited to, floor or wall covering, which incorporates selectively applied matrix layers of discreet, low aspect ratio particles embedded in a resinous coating.
While the invention has been described with respect to certain embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.
|
The invention provides decorative, inlaid sheet materials which incorporate one or more selectively deposited matrix layers of discrete, low aspect ratio particles embedded in a resinous coating. The use of printed patterns which are visible beneath the adhesive matrix containing the particles constitutes one embodiment of the invention. The sheet materials of this invention are real through-patterned inlaids which do not lose their pattern due to wear in use, and which offer unique design advantages and flexibility, as well as superior properties.
| 1
|
BACKGROUND OF THE INVENTION
The present invention relates to a process camera for printing pictures of different sizes in the desired display positions on a photosensitive material to obtain a press plate.
Usually, when a book is made by bookbinding, a plurality of pages are printed in both surfaces of a large printing paper, and thus the printing paper is folded to prepare one "section" which usually includes an octavo 16 pages and is the minimum unit for bookbinding. A plurality of sections are binded together to produce a book. The number and arrangement of the pages to be printed on the printing paper depend on the plate sizes, the size of the printing paper, the type and the size of the printer, the printing style, and so forth.
In FIGS. 1 and 2 there are shown both surfaces of an octavo 16 pages of one section of the printed paper 1 wherein a signature or a nigger head 2 and register marks 3 are attached, and wherein page numbers such as 1p-16p and photographing numbers I-VIII, hereinafter mentioned, are shown. The printed paper 1 is obtained in a conventional manner as follows:
(i) Each of the pages is photographed one by one on the film to produce negative plates for one section of one printing paper, and thus the obtained negative plates for the one section are arranged on a base film in the desired positions (for example, as shown in FIGS. 1 and 2). Then, the negative plates arranged on the base film are printed on a photosensitive material by exposing the light thereon, thereby obtaining a press plate.
(ii) The pages for one section of one printing paper are arranged on a base sheet in the desired positions, and the pages arranged on the base sheet are photographed on a film to obtain a large negative plate. Then, the large negative plate is printed on a photosensitive material, thereby obtaining a press plate.
(iii) Each of the pages is photographed one by one on a microfilm in the reduced scale, in advance, and then the necessary pages for the one section of the printing paper are automatically picked up and are projected to a photosensitive material in the desired display positions, thereby obtaining a press plate.
The method (i) is mostly carried out, but this method is performed manually in the most steps. Accordingly, it takes a lot of time and labors and an operational mistake is apt to be happened.
The method (ii) is often practiced and the time and the labors are considerably saved. However, the display of the pages on the base sheet is carried out manually, and hence a mistake is liable to arise. Further, since the pages displayed on the base sheet for one section is photographed altogether by one operation, a large process camera is required.
The method (iii) is effective for saving the labors and materials. However, the reducing and the enlarging photographing steps by optical systems are involved, and thus the quality of the reproduction image is lowered. Further, a costly apparatus is required. Accordingly, this method is less practiced now.
In order to remove these disadvantages of the conventional methods, another process camera has been proposed, as disclosed in Japanese patent application No. 55-153427.
However, in this embodiment, when the page is photographed upside-down with respect to the printing paper, a picture holder having a pair of register pins for positioning the page is rotated through 180 degree. Hence, the construction of the picture holder is complicated and costly, and the rotation of the picture holder requires more time than usual.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a process camera for printing pictures of different sizes in the desired display positions on a photosensitive material free from the aforementioned disadvantages and inconveniences, which is compact, simple and low-priced, and which is capable of performing a quick, simple and reliable operation.
According to the present invention there is provided a process camera for printing pictures of different sizes in the desired display positions on a photosensitive material, comprising (a) an object holder on which an object to be photographed is mounted and which includes a light for illuminating the object, (b) a photosensitive material holder on which a photosensitive material is mounted, (c) a lens holder for holding a lens which focuses the object onto the photosensitive material, wherein these three holders are aligned in series on and along a light axis of the lens, wherein the lens holder is positioned between the object holder and the photosensitive material holder, wherein the object holder is movable towards and away from the lens holder, and wherein the photosensitive material holder is movable in x and y directions perpendicular to the light axis, and (d) a plurality of register pins and respective drive means for positioning the objects of different sizes, which are mounted to the object holder so that each of the register pins may be independently projected through or beyond the object holder by the respective drive means.
BRIEF DESCRIPTION OF DRAWINGS
In order that the present invention may be better understood, a preferred embodiment thereof will be described with reference to the accompanying drawings, in which:
FIG. 1 shows a surface of a printed paper;
FIG. 2 shows a reverse surface of the printed paper of FIG. 1;
FIG. 3 is a side view of a process camera according to the present invention;
FIG. 4 is top plan view of a manuscript holder shown in FIG. 3;
FIG. 5 is a side view of FIG. 4;
FIG. 6 is an elevational view of means for holding a photosensitive material of FIG. 3;
FIG. 7 is a longitudinal cross section, taken along the line VII--VII of FIG. 6;
FIG. 8 is a block diagram of a control system of the process camera according to the present invention; and
FIG. 9 shows a flow chart for operating the process camera according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings there is shown in FIG. 3 a process camera according to the present invention, which comprises a photographing section A mounted to the front of a base 4, a photosensitive material holding section B mounted movably front- and rearwards to the base 4, and a control section C positioned in front of the base 4. The photosensitive material holding section B is light-shielded by the photographing section A and a dark box 5.
In the photographing section A, a standframe 6 is arranged upright in the front part of the base 4, and a lens holder 7 is mounted to the upper front of the standframe 6. A lens 8 is detachably mounted to the front of the lens holder 7. A plane mirror 9 inclining at 45 degree is detachably mounted to the central front of the lens 8.
A manuscript holder 10 having a square form, as shown in FIGS. 4 and 5, is movably mounted to the standframe 6 under the lens holder 7 and is movable up and down. A plurality of register pins P 1 -P 4 , P 5 -P 8 , P 9 -P 12 , and P 13 -P 16 are so mounted to the manuscript holder 10 that they may be positioned in vertices of squares formed thereby and thus on diagonals of an upper plate 10a of the manuscript holder 10 and that they may be projected upwards beyond the upper plate 10a means of solenoids or air cylinders S 1 -S 16 arranged under the respective register pins.
Each register pin is biased downwards below the upper surface of the upper plate 10a by a coil spring 11 which is fitted around the register pin and is positioned between the upper plate 10a and the respective solenoid. When the solenoids S 1 -S 16 are activated, the tops of the respective register pins P 1 -P 16 are projected at a certain length beyond the upper plate 10a. When the solenoids S 1 -S 16 are deactivated, the register pins P 1 -P 16 are retracted in the manuscript holder 10.
The positions of the register pins P 1 -P 16 are determined so that various sizes of manuscripts 12 may be mounted in the center of the manuscript holder 10 while the manuscripts 12 direct upwards, downwards, leftwards or rightwards in FIG. 4. For example, when the register pins P 9 and P 10 are projected by actuating the respective solenoids S 9 and S 10 , the manuscript 12 can be placed in the center of the manuscript holder 10 by fitting holes formed in the left side of the manuscript 12 onto the register pins P 9 and P 10 , as shown by a two-dotted line.
The upper plate 10a is provided with suction grooves 13 for different sizes of the manuscript to be mounted to the upper plate 10a, which are led to a suction means (not shown). A bracket 14 and a pair of other brackets 15 are mounted to the rear end of the manuscript holder 10 in its center and side parts, in parallel.
A nut 16 horizontally attached to the rear free end of the central bracket 14, is engaged with a vertical screw rod 17 which is rotatably mounted to the central front part of the standframe 6. The standframe 6 is provided with a pair of front projection members 6a in its right and left ends along its entire vertical length. A pair of rails 19 are mounted to the opposite inner surfaces of the front projection members 6a along their entire vertical lengths. A pair of guide rollers 18 are rotatably mounted to the outer side of each side bracket 15 in contact with the front and the rear surfaces of each rail 19. Hence, the vertical rod 17 is rotated by a drive motor M 1 mounted to the base 4, thereby moving up and down the manuscript holder 10 along the standframe 6.
Reflective illumination lights sources 20 are mounted to the manuscript holder 10 via support rods.
The photosensitive material holding section B comprises a frame 21 which are movably mounted to the base 4 and is moved front- and rearwards. A flash lamp 22 is hung on the inner central upper top of the frame 21, and a mask 24 is disposed to the front of a window opening 23 formed in the center of a front plate 21a of the frame 21, and is detachable.
Means 25 for holding a photosensitive material 48 is pivotally mounted to the lower front part of the frame 21 via a horizontal pivot shaft 26 which is pivotally connected to the base end of the means 25. An air cylinder 27 connects the middle part of the means 25 and the upper part of the front plate 21a. Thus, the means 25 is pivoted between the horizontal position shown by two-dotted lines and the vertical position for the photographing by extending and retracting the air cylinder 27, as shown in FIG. 3.
In FIGS. 6 and 7, there is shown the means 25 for holding the photosensitive material 48. A base frame 28 of the means 25 is provided with a central square opening 29 in its center. A screw rod 30 and a guide rod 31 are rotatably mounted to the inner parts of the base frame 28 by bearings 32 in parallel with the opposite sides of the central square opening 29, as shown in the upper and the lower parts of FIG. 6. A drive motor M 2 is connected to one end of the screw rod 30 and is mounted to the base frame 28.
A movable frame 33 having approximately the same size as the central square opening 29 of the base frame 28 is provided with a nut 34 and a guide pipe 35 in its opposite sides of the periphery, which engage with the screw rod 30 and the guide rod 31, respectively (see FIG. 6).
A guide rod 36 and a screw rod 37 are rotatably mounted, in parallel, to the opposite sides of the movable frame 33 by bearings 38, and extends in the direction perpendicular to the screw rod 30 and the guide rod 31. A drive motor M 3 is connected to one end of the screw rod 37 in order to drive it.
A photosensitive material holder 39 having a square form and approximately the same dimension as the inner opening of the movable frame 33 is provided with a guide pipe 40 and a nut 41 in its opposite sides of the periphery, which engage with the guide rod 36 and the screw rod 37, respectively. The photosensitive material holder 39 is also provided with suction grooves 42 on its surface and a pair of register pins 43 in its one side for positioning the photosensitive material 48.
Thus the constructed photosensitive material holder 39 can be moved upwards, downwards, rightwards and leftwards in FIG. 6 by the drive motors M 2 and M 3 .
The control section C is connected to the process camera described above via a leading wire (not shown), and comprises an operational board 44, a central processing unit 45, hereinafter referred to as CPU, an interface 46, a motor drive unit 47, a display (not shown), and so forth.
The operation of the process camera of the present invention described above in order to produce the printed paper 1 shown in FIGS. 1 and 2, will be described with reference to FIGS. 8 and 9.
In the CPU 45 of the control section C, the sizes of the printing papers, the types and dimensions of the printers, and various modes relating to the numbers of the manuscripts to be printed for one section of the printing paper and their display positions are stored, in advance. One of these modes is selected freely by operating the operational board 44.
First, a power switch is turned on, and the CPU 45 drives the motor drive unit 47 via the interface 46, with the result that a motor for driving the photosensitive material holding section B and the three drive motors M 1 , M 2 and M 3 are drive in order to return the photosensitive material holding section B, the manuscript holder 10 and the photosensitive material holder 39 to their starting points, and deactivates all the solenoids S 1 -S 16 of the manuscript holder 10, resulting in retraction of the register pins P 1 -P 16 within the manuscript holder 10.
Then, a photographing magnification which is determined depending on the number of the manuscripts for one section of the printing paper, photographing order, the size of the book-binding, and the sizes of the manuscripts, is set up in the operational board 44, and an automatic focusing means of a conventional type (not shown) is driven by operating a button of the operational board 44 to focus the lens 8 with the desired magnification.
Next, the means 25 is positioned in horizontal position by extending the air cylinder 27, and then, the photosensitive material 48 and an overlaying mask (not shown) are positioned on the photosensitive material holder 39 by using the register pins 43. The photosensitive material is retained on the photosensitive material holder 39 by actuating a suction means (not shown) which sucks the suction grooves 42. Then, a signature or nigger head 2 and register marks 3 are printed on the photosensitive material 48 by lighting the flash lamp 22.
Then, the overlaying mask is released from the photosensitive material 48, and the means 25 is positioned into the vertical position by retracting the air cylinder 27. Then, the operation is carried out according to the selected mode, i.e. the drive motors M 2 and M 3 are automatically driven to move the photosensitive material holder 39 to the desired position of the photosensitive material 48, such that the position corresponding to the exposure number I of the paper 1 shown in FIG. 1 may be adjusted to be on the light axis X-Y, and the exposure number I of the surface of the paper 1 is displayed on the display of the operational board 44 in the same time.
In the same time, when the manuscript 12 is of A-4 size, the solenoids S 9 and S 10 are actuated to project the register pins P 9 and P 10 beyond the manuscript holder 10, and the manuscript 12 is positioned in the center of the manuscript holder 10 by means of the register pins P 9 and P 10 while the suction grooves 13 are sucked to hold the manuscript 12 tightly.
On this occasion, the paper number of the manuscript 12 and the exposure order are displayed on the display of the operational board 44. Since the manuscript 12 is positioned by means of the register pins P 9 and P 10 with the result that its positioning direction is determined, the manuscript 12 can be mounted to the manuscript holder 10 without any mistake.
Then, the light sources 20 are illuminated and the exposure is carried out by operating the operational board 44, thereby finishing the exposure of the first page in the position corresponding to the exposure number I of the paper 1 of FIG. 1. Then, the photosensitive material holder 39 is automatically moved to the position corresponding to the exposure number II according to the selected mode, and the exposure number II and the page number 16 are displayed on the display of the operational board 44 in the same time. The exposure operation is carried out automatically in the same manner as described above.
Then, when the exposure number becomes V, the CPU 45 gives the instructions to deactivate the solenoids S 9 and S 10 and to activate the solenoids S 11 and S 12 , so that the register pins P 9 and P 10 may be retracted within the manuscript holder 10 and the register pins P 11 and P 12 may be projected beyond the same. Hence, the manuscript 12 can be positioned upsidedown on the manuscript holder 10 without any mistake. Other operations are performed in the same manner as described above, thereby finishing the printing of all manuscripts 12 on the surface of the paper 1. Then, the photosensitive material holder 39 is returned to the starting point automatically.
Next, the photosensitive material 48 is replaced with a new one, and the reverse surface of the paper 1 of FIG. 2 is printed in the same manner as described above.
It is readily understood from the above description that the manuscripts can be automatically printed one by one on a photosensitive material in the desired display positions according to the displayed indications on the display of the operational board, except that the manuscripts and positioned one be one onto the manuscript holder in the indicated exposure order by an operator, according to the present invention. Accordingly, there is no danger to occur any mistake.
Further, according to the present invention the manuscripts are processed one by one, and thus the photographing section is designed so compact and low-priced.
In this process camera, by replacing the plane mirror 9 with a roof mirror, a press plate print and a film photographing can be readily carried out without changing the light axis.
In the process camera of the present invention, the installation space required is less than a process camera of a horizontal type, and further the exchange of the manuscripts can be performed in the horizontal position and thus the operation is carried out quickly and easily.
Although the present invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will, of course, be understood that various changes and modifications thereof may be made in the form, details, and arrangements of the parts without departing from the scope of the present invention.
|
A process camera for printing pictures of different sizes in the desired display positions on a photosensitive material to obtain a press plate, wherein a manuscript holder for mounting a manuscript to be printed, a lens holder including a focusing lens, and a photosensitive material holder for mounting a photosensitive material are aligned in series on and along the light axis, the manuscript holder being movable towards and away from the lens holder, and the photosensitive material holder being movable in the perpendicular directions to the light axis, and wherein a plurality of register pins and respective drive means for positioning the manuscripts of different sizes are provided in the manuscript holder, and each of the register pins is independently projected beyond the manuscript holder by the respective drive means.
| 6
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the US National Stage of International Application No. PCT/EP2006/060835, filed Mar. 17, 2006 and claims the benefit thereof. The International Application claims the benefits of European Patent Office application No. 05012633.3 filed Jun. 13, 2005, both of the applications are incorporated by reference herein in their entirety.
FIELD OF INVENTION
[0002] The invention relates to a component having a thermal barrier coating and a metallic erosion-resistant, to a production process and to a method for operating a steam turbine.
BACKGROUND OF INVENTION
[0003] Thermal barrier coatings which are applied to components are known from the field of gas turbines, as described for example in EP 1 029 115.
[0004] Thermal barrier coatings enable components to be used at higher temperatures than those permitted by the base material, or allow the service life to be extended.
[0005] Known base materials (substrates) for gas turbines allow temperatures of use of at most 1000° C. to 1100° C., whereas a coating with a thermal barrier coating allows temperatures of use of up to 1350° C.
[0006] The temperatures of use of components in a steam turbine are much lower, and consequently these demands are not imposed in this application.
[0007] It is known from EP 1 029 104 A to apply a ceramic erosion-resistant layer to a ceramic thermal barrier coating of a gas turbine blade or vane.
[0008] It is known from DE 195 35 227 A1 to provide a thermal barrier coating in a steam turbine in order to allow the use of materials which have worse mechanical properties but are less expensive for the substrate to which the thermal barrier coating is applied.
[0009] U.S. Pat. No. 5,350,599 discloses an erosion-resistant ceramic thermal barrier coating.
[0010] US 2003/0152814 A1 discloses a thermal barrier coating system comprising a substrate made from a superalloy, an aluminum oxide layer on the substrate and a ceramic as outer ceramic thermal barrier coating.
[0011] EP 0 783 043 A1 discloses an erosion-resistant layer consisting of aluminum oxide or silicon carbide on a ceramic thermal barrier coating.
[0012] U.S. Pat. No. 5,683,226 discloses a component of a steam turbine with improved resistance to erosion.
[0013] U.S. Pat. No. 4,405,284 discloses an outer metallic layer which is considerably more porous than the underlying ceramic thermal barrier coating.
[0014] In its discussion of the prior art, EP 0 783 043 A1 discloses the formation of an erosion-resistant coating in two layers, specifically comprising an inner metallic layer and an outer ceramic layer.
[0015] U.S. Pat. No. 5,740,515 discloses a ceramic thermal barrier coating to which an outer, hard ceramic silicide coating has been applied.
[0016] WO 00/70190 discloses a component wherein an outer metallic layer is applied, this layer containing aluminum in order to increase the oxidation resistance of the component.
[0017] The thermal barrier coating is strongly eroded on account of impurities in a medium and/or high flow velocities of the flowing medium which flows past components having a thermal barrier coating.
SUMMARY OF INVENTION
[0018] Therefore, it is an object of the invention to provide a component, a process for producing the component and a suitable use of the layer system which overcomes this problem.
[0019] The object is achieved by a component and a method as claimed in independent claims.
[0020] The subclaims list further advantageous configurations of the components according to the invention.
[0021] The measures listed in the subclaims can be combined with one another in advantageous ways.
[0022] In particular in the case of components of turbines which are exposed to hot fluids for driving purposes, scaling often leads to mechanical impact of detached scale particles on a brittle ceramic layer, which could lead to material breaking off, i.e. to erosion. Although the ceramic layer is designed to withstand thermal shocks, it is susceptible to locally very limited occurrences of mechanical stresses, since a thermal shock has a more widespread effect on the overall layer.
[0023] Therefore, a metallic erosion-resistant layer is particularly advantageous, since it is elastically and plastically deformable on account of its ductility.
[0024] The thermal barrier coating does not necessarily serve only to shift the range of use temperatures upward, but rather is also advantageously used to reduce and/or make more even the thermal expansion caused by the temperature differences which are produced and/or present at the component. It is in this way possible to avoid or at least reduce thermomechanical stresses.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Exemplary embodiments are illustrated in the figures, in which:
[0026] FIG. 1 shows possible arrangements of a thermal barrier coating according to the invention on a component,
[0027] FIGS. 2 , 3 show a porosity gradient within the thermal barrier coating of a component formed in accordance with the invention,
[0028] FIGS. 4 , 5 show a steam turbine,
[0029] FIGS. 6 , 7 , 8 show further exemplary embodiments of a component formed in accordance with the invention.
DETAILED DESCRIPTION OF INVENTION
[0030] FIG. 1 shows a first exemplary embodiment of a layer system 1 formed in accordance with the invention for a component. In the text which follows, the terms layer system 1 and component are used synonymously when the component includes the layer system 1 .
[0031] The component 1 is preferably a component of a gas or steam turbine 300 , 303 ( FIG. 4 ), in particular a steam inflow region 333 of a steam turbine 300 , a turbine blade or vane 342 , 354 , 357 ( FIG. 4 ) or a housing part 334 , 335 , 366 ( FIGS. 4 , 5 ) and comprises a substrate 4 (supporting structure) and a thermal barrier coating 7 applied to the substrate, as well as an outer metallic erosion-resistant layer 13 on the thermal barrier coating 7 . At least one metallic bonding layer 10 is arranged between the substrate 4 and the thermal barrier coating 7 . The bonding layer 10 is used to protect the substrate 4 from corrosion and/or oxidation and/or to improve the bonding of the thermal barrier coating 7 to the substrate 4 . This applies in particular if the thermal barrier coating 7 consists of ceramic and the substrate 4 consists of a metal.
[0032] The erosion-resistant layer 13 consists of a metal or a metal alloy and protects the component from erosion and/or wear, as is the case in particular for steam turbines 300 , 303 ( FIG. 4 ), which are subject to scaling, and in which mean flow velocities of approximately 50 m/s (i.e. 20 m/s-100 m/s) and pressures from 350 to 400 bar occur.
[0033] The outer metallic erosion-resistant layer 13 (=outermost layer) is preferably formed to be denser than the thermal barrier coating 7 .
[0034] In this context, the term denser means that the porosity of the outer metallic erosion-resistant layer 13 is in absolute terms at least 1%, in particular at least 3%, higher than that of the thermal barrier coating 7 (for example ρ(7)=90%, i.e. ρ(13)≦91%, in particular≦93%)
[0035] The density of the thermal barrier coating 7 is preferably 80%-95% of the theoretical density, while the density p of the metallic erosion-resistant layer 13 is preferably at least 96%, preferably 98% of the theoretical density.
[0036] The term metal is to be understood as encompassing not just elemental metals but also alloys, solid solutions or intermetallic compounds.
[0037] According to the invention, the bonding layer 10 and the erosion-resistant layer 13 have an identical or similar composition.
[0038] An identical composition means that the two layers 10 , 13 contain the same elements in the same amounts, preferably comprising an MCrAlX alloy or SC 21 , SC 23 or SC 24 . The preferred use of an identical composition for the erosion-resistant layer 13 simplifies procurement and also significantly improves the corrosion properties of the substrate 4 .
[0039] A similar composition means that the two layers 10 , 13 contain the same elements but in slightly differing proportions, i.e. differences of at most 3% per element (for example layer 10 may have a chromium content of 30%, in which case the layer 13 may have a chromium content from at least 27% (30-3) to at most 33% (30+3)) and that up to 1 wt % of at least one further element may be present.
[0040] SC 21 consists of (in wt %) 29%-31% nickel, 27%-29% chromium, 7%-8% aluminum, 0.5%-0.7% yttrium, 0.3%-0.7% silicon, remainder cobalt.
[0041] SC 23 consists of (in wt %) 11%-13% cobalt, 20%-22% chromium, 10.5%-11.5% aluminum, 0.3%-0.5% yttrium, 1.5%-2.5% rhenium, remainder nickel.
[0042] SC 24 consists of (in wt %) 24%-26% cobalt, 16%-18% chromium, 9.5%-11% aluminum, 0.3%-0.5% yttrium, 1.0%-1.8% rhenium, remainder nickel.
[0043] The wear-/erosion-resistant layer 13 preferably consists of alloys based on iron, chromium, nickel and/or cobalt or for example NiCr 80/20 or NiCrSiB with admixtures of boron (B) and silicon (Si) or NiAl (for example: Ni: 95 wt %, Al 5 wt %).
[0044] In particular, a metallic erosion-resistant layer 13 can be used for steam turbines 300 , 303 , since the use temperatures in steam turbines at the steam inflow region 333 are at most 450° C., 550° C., 650° C., 750° C. or 850° C.
[0045] It is preferable to use a temperature of 750° C.
[0046] For these temperature ranges, there are sufficient metallic layers which have a sufficiently high resistance to erosion over the service life of the component 1 combined, at the same time, with a good resistance to oxidation.
[0047] Metallic erosion-resistant layers 13 in gas turbines on a ceramic thermal barrier coating 7 within the first stage of the turbine or within the combustion chamber are not appropriate, since metallic erosion-resistant layers 13 as an outer layer are unable to withstand the use temperatures of up to 1350° C.
[0048] The bonding layer 10 for protecting a substrate 4 from corrosion and oxidation at a high temperature includes, for example, substantially the following elements (details of the contents in percent by weight):
[0000] 11.5 to 20.0 wt % chromium,
0.3 to 1.5 wt % silicon,
0.0 to 1.0 wt % aluminum,
0.0 to 0.7 wt % yttrium and/or at least one equivalent metal selected from the group consisting of scandium and the rare earth elements,
remainder iron, cobalt and/or nickel as well as manufacturing-related impurities.
[0049] In particular the metallic bonding layer 10 consists of
[0000] 12.5 to 14.0 wt % chromium,
0.5 to 1.0 wt % silicon,
0.1 to 0.5 wt % aluminum,
0.0 to 0.7 wt % yttrium and/or at least one equivalent metal selected from the group consisting of scandium and the rare earth elements,
remainder iron and/or cobalt and/or nickel as well as manufacturing-related impurities.
[0050] It is preferable if the remainder of these two bonding layers 10 is iron alone.
[0051] The composition of the bonding layer 10 based on iron has particularly good properties, with the result that the bonding layer 10 is eminently suitable for application to ferritic substrates 4 .
[0052] The coefficients of thermal expansion of substrate 4 and bonding layer 10 can be very well matched to one another (up to 10% difference) or may even be identical, so that no thermally induced stresses are built up between substrate 4 and bonding layer 10 (thermal mismatch), which could cause the bonding layer 10 to flake off.
[0053] This is particularly important since in the case of ferritic materials, it is often the case that there is no heat treatment carried out for diffusion bonding, but rather the bonding layer 10 (ferritic) is bonded to the substrate 4 mostly or solely through adhesion.
[0054] The composition of the outer erosion-resistant layer 13 is selected in such a way as to have a high ductility. In this context, the term high ductility means an elongation at break of 5% (an elongation of 5% leads to the formation of cracks) at the temperature of use.
[0055] An erosion-resistant layer 13 having a ductility of this level may be present directly on a substrate 4 or on a ceramic thermal barrier coating 7 , in which case the composition of the bonding layer 10 is then no longer of importance.
[0056] The thermal barrier coating 7 is in particular a ceramic layer which for example consists at least in part of zirconium oxide (partially stabilized or fully stabilized by yttrium oxide and/or magnesium oxide) and/or at least in part of titanium oxide and is, for example, thicker than 0.1 mm. By way of example, it is possible to use thermal barrier coatings 7 consisting 100% of either zirconium oxide or titanium oxide.
[0057] The ceramic layer 7 can be applied by means of known coating processes, such as atmospheric plasma spraying (APS), vacuum plasma spraying (VPS), low-pressure plasma spraying (LPPS) and by chemical or physical coating methods (CVD, PVD).
[0058] The substrate 4 is preferably a steel or other iron-base alloy (for example 1% CrMoV or 10-12% chromium steels) or a nickel- or cobalt-base superalloy.
[0059] In particular, the substrate 4 is a ferritic base alloy, a steel or nickel- or cobalt-base superalloy, in particular a 1% CrMoV steel or a 10 to 12% chromium steel.
[0060] Further advantageous ferritic substrates 4 of the layer system 1 consist of a 1% to 2% Cr steel for shafts ( 309 , FIG. 4 ):
such as for example 30CrMoNiV5-11 or 23CrMoNiWV8-8, 1% to 2% Cr steel for housings (for example 335 , FIG. 4 ): G17CrMoV5-10 or G17CrMo9-10, 10% Cr steel for shafts ( 309 , FIG. 4 ): X12CrMoWVNbN10-1-1, 10% Cr steel for housings (for example 335 , FIG. 4 ): GX12CrMoWVNbN10-1-1 or GX12CrMoVNbN9-1.
[0065] To optimize the efficiency of the thermal barrier coating 7 , the thermal barrier coating 7 at least in part has a certain open and/or closed porosity.
[0066] It is preferable for the erosion-resistant layer 13 to have a higher density than the thermal barrier coating 7 , so that it ( 13 ) has a higher resistance to erosion.
[0067] The metallic erosion-resistant layer 13 has a very low porosity and in particular has a relatively low roughness, so as to provide a good resistance to removal of material through erosion.
[0068] The lower porosity and roughness of the metallic erosion-resistant layer can be achieved using varying techniques:
[0000] 1. Use of a spray powder with the smallest possible grain size during the thermal spraying of the erosion-resistant layer 13 ,
2. densification of the outer metallic erosion-resistant layer 13 after spraying by a blasting operation, for example by blasting with glass beads or steel grit or other mechanical densification or smoothing processes (rolling, vibratory finishing),
3. closing of the open pores by penetration agents,
4. heat treatment of the entire system,
5. fusion or remelting of the top layer or of the entire metallic erosion-resistant layer.
[0069] By contrast, the bonding layer 10 , which is located between the substrate and the thermal barrier coating, is implemented in such a way as to have a sufficiently high roughness with undercuts, in order to effect secure bonding of the thermal barrier coating to the bonding layer 10 . In this case, the powder used during the spraying operation can be significantly coarser than that used for the erosion-resistant layer 13 .
[0070] FIG. 2 shows a porous thermal barrier coating 7 with a porosity gradient.
[0071] Pores 16 are present in the thermal barrier coating 7 . The density ρ of the thermal barrier coating 7 increases in the direction of an outer surface.
[0072] Therefore, the layer 7 can be used as a thermal barrier in the region where the porosity is greater and if appropriate can also be used to protect against erosion in the region where the porosity is lower. Therefore, there is preferably a greater porosity toward the bonding layer 10 than in the region of an outer surface or the contact surface with the erosion-resistant layer 13 .
[0073] In FIG. 3 , the gradient of the density p of the thermal barrier coating 7 is opposite to that shown in FIG. 2 .
[0074] The erosion-resistant layer 13 is preferably only applied locally, and is preferably applied to the component 1 where the angle at which eroding particles impinge on the component 1 is between 60° and 120°, preferably between 70° and 110° or preferably around 80° and 100°. It is particularly useful to coat the locations where the eroding particles impinge at an angle of 90° +/−2°. A metallic erosion-resistant layer 13 offers the best protection against erosion with this virtually perpendicular impingement of eroding particles on the surface of a component 1 . The perpendicular to the surface of the component 1 constitutes the 90° axis.
[0075] FIG. 4 illustrates, by way of example, a steam turbine 300 , 303 with a turbine shaft 309 extending along an axis of rotation 306 .
[0076] The steam turbine has a high-pressure part-turbine 300 and an intermediate-pressure part-turbine 303 , each having an inner housing 312 and an outer housing 315 surrounding the inner housing. The high-pressure part-turbine 300 is, for example, of pot-like design. The intermediate-pressure part-turbine 303 is of two-flow design. It is also possible for the intermediate-pressure part-turbine 303 to be of single-flow design. Along the axis of rotation 306 , a bearing 318 is arranged between the high-pressure part-turbine 300 and the intermediate-pressure part-turbine 303 , the turbine shaft 309 having a bearing region 321 in the bearing 318 . The turbine shaft 309 is mounted on a further bearing 324 next to the high-pressure part-turbine 300 . In the region of this bearing 324 , the high-pressure part-turbine 300 has a shaft seal 345 . The turbine shaft 309 is sealed with respect to the outer housing 315 of the intermediate-pressure part-turbine 303 by two further shaft seals 345 . Between a high-pressure steam inflow region 348 and a steam outlet region 351 , the turbine shaft 309 in the high-pressure part-turbine 300 has the high-pressure rotor blading 354 , 357 . This high-pressure rotor blading 354 , 357 , together with the associated rotor blades (not shown in more detail), constitutes a first blading region 360 . The intermediate-pressure part-turbine 303 has a central steam inflow region 333 . Assigned to the steam inflow region 333 , the turbine shaft 309 has a radially symmetrical shaft shield 363 , a cover plate, on the one hand for dividing the flow of steam between the two flows of the intermediate-pressure part-turbine 303 and also for preventing direct contact between the hot steam and the turbine shaft 309 . In the intermediate-pressure part-turbine 303 , the turbine shaft 309 has a second blading region 366 having the intermediate-pressure rotor blades 354 , 342 . The hot steam flowing through the second blading region 366 flows out of the intermediate-pressure part-turbine 303 from an outflow connection piece 369 to a low-pressure part-turbine (not shown) which is connected downstream in terms of flow.
[0077] The turbine shaft 309 is composed of two turbine part-shafts 309 a and 309 b , which are fixedly connected to one another in the region of the bearing 318 .
[0078] In particular, the steam inflow region 333 has a thermal barrier coating 7 and an erosion-resistant layer 13 .
[0079] FIG. 5 shows an enlarged illustration of a region of the steam turbine 300 , 303 .
[0080] In the region of the inflow region 333 , the steam turbine 300 , 303 comprises an outer housing 334 , which is exposed to temperatures of between 250° and 350° C.
[0081] Temperatures of from 450° to 800° C. are present at the inflow region 333 as part of an inner housing 335 .
[0082] This results in a temperature difference of at least 200° C.
[0083] At the inner housing 335 , which is exposed to the high temperatures, the thermal barrier coating 7 , together with the erosion-resistant layer 13 , is applied to the inner side 336 (for example not to the outer side 337 ).
[0084] The thermal barrier coating 7 is locally present only at the inner housing 335 (and for example not in the blading region 366 ).
[0085] The application of a thermal barrier coating 7 with the erosion-resistant layer 13 reduces the introduction of heat into the inner housing 335 , with the result that the thermal expansion properties are influenced. As a result, all the deformation properties of the inner housing 335 and the steam inflow region 333 can be set in a controlled way.
[0086] This can be achieved by varying the thickness of the thermal barrier coating 7 or applying different materials at different locations of the surface of the inner housing 335 .
[0087] It is also possible for the porosity to be different at different locations of the inner housing 335 .
[0088] The thermal barrier coating 7 can be applied locally, for example in the inner housing 335 in the region of the inflow region 333 .
[0089] It is also possible for the thermal barrier coating 7 to be applied locally only in the blading region 366 ( FIG. 6 ).
[0090] The use of an erosion-resistant layer 13 is required in particular in the inflow region 333 .
[0091] If the thermal barrier coating 7 (TBC) with erosion-resistant layer 13 is present in the inflow region 333 , a thermal barrier coating 7 without erosion-resistant layer may be present in the blading region 366 and/or the turbine blades or vanes.
[0000]
Inflow region
Blading region
Turbine blade or vane
TBC
Yes + 13
No
No
TBC
Yes + 13
Yes
No
TBC
Yes + 13
No
Yes
TBC
Yes + 13
Yes + 13
No
TBC
Yes
Yes + 13
No
TBC
Yes
No
Yes + 13
[0092] FIG. 7 shows a further exemplary embodiment of a component 1 according to the invention.
[0093] In this case, the thickness of the thermal barrier coating 7 is configured to be thicker in the inflow region 333 than in the blading region 366 of the steam turbine 300 , 303 .
[0094] The locally differing thickness of the thermal barrier coating 7 is used for controlled setting of the introduction of heat and therefore the thermal expansion and consequently the expansion properties of the inner housing 334 , comprising the inflow region 333 and the blading region 366 .
[0095] Since higher temperatures are present in the inflow region 333 than in the blading region 366 , the thicker thermal barrier coating 7 in the inflow region 333 reduces the introduction of heat into the substrate 4 to a greater extent than in the blading region 366 , where the temperatures are lower. Therefore, the introduction of heat can be kept at approximately equal levels in the inflow region 333 and the adjoining blading region 366 , resulting in an approximately equal thermal expansion.
[0096] It is also possible for a different material to be used in the region of the inflow region 333 than in the blading region 366 . Here, the thermal barrier coating 7 is applied throughout the entire hot zone, i.e. everywhere, and includes the erosion-resistant layer 13 .
[0097] FIG. 8 shows another application example for the use of a thermal barrier coating 7 .
[0098] The component 1 , in particular a housing part, is in this case a valve housing 31 , into which a hot steam flows through an inflow passage 46 .
[0099] The inflow passage 46 mechanically weakens the valve housing.
[0100] The valve housing 31 comprises, for example, a pot-shaped housing part 34 and a cover 37 .
[0101] Inside the housing part 31 there is a valve comprising a valve cone 40 and a spindle 43 .
[0102] Component creep leads to uneven axial deformation of the housing 31 and cover 37 . The valve housing 31 would expand to a greater extent in the axial direction in the region of the passage 46 , leading to tilting of the cover together with the spindle 43 , as indicated by dashed lines. As a result, the valve cone 34 is no longer seated correctly, which reduces the leak tightness of the valve.
[0103] The application of a thermal barrier coating 7 to an inner side 49 of the housing 31 makes the deformation properties more uniform, so that both ends 52 , 55 of the housing 31 and of the cover 37 expand evenly.
[0104] Overall, the application of the thermal barrier coating 7 serves to control the deformation properties and therefore to ensure the leak tightness of the valve.
[0105] The thermal barrier coating 7 once again includes the erosion-resistant layer 13 .
|
There are described components of a steam turbine, comprising a thermally insulating layer and a metallic anti-erosion layer on said thermally insulating layer. The anti-erosion layer is provided with the same material as the metallic connecting layer.
| 8
|
FIELD OF THE INVENTION
[0001] This invention relates to delivering prostheses into the body.
BACKGROUND OF THE INVENTION
[0002] Prostheses, such as stents, grafts and the like, are placed within the body to improve the function of a body lumen. For example, stents with substantial elasticity can be used to exert a radial force on a constricted portion of a lumen wall to open a lumen to near normal size.
[0003] These stents can be delivered into the lumen using a system which includes a catheter, with the stent supported near its distal end, and a sheath, positioned coaxially about the catheter and over the stent.
[0004] Once the stent is located at the constricted portion of the lumen, the sheath is removed to expose the stent, which is expanded so it contacts the lumen wall. The catheter is subsequently removed from the body by pulling it in the proximal direction, through the larger lumen diameter created by the expanded prosthesis, which is left in the body.
SUMMARY OF THE INVENTION
[0005] This invention provides smooth delivery and accurate positioning of prostheses in the body. In embodiments, systems are provided that include elongate members extending generally along the axis of a supporting catheter to a free ends. The elongate members extend through openings in the prosthesis to maintain the position of the prosthesis on the catheter. The prosthesis can be released from the catheter by relative axial motion of the catheter and the elongate members such that the free ends are removed from the openings in the prosthesis. In embodiments, the elongate members hold the distal end of a self-expanding stent at a desired axial location and in radial compaction as a restraining sheath is withdrawn. The friction between the sheath and stent puts the stent under tension, which reduces the radial force on the sheath wall, allowing smoother retraction. Proximal portions of the stent radially expand and axially shorten. The distal end, however, is maintained at the desired axial location and released from the catheter to contact the body lumen wall without substantial axial shortening.
[0006] In an aspect, the invention features a system for positioning a prosthesis in contact with tissue within a patient. The system includes a prosthesis having proximal and distal ends and a tissue-engaging body therebetween. The prosthesis has a radially compact form for delivery into the patient and is radially expandable along its body for engaging tissue. The length of the prosthesis varies in dependence on the expansion of the body. The system further includes a catheter having a portion for supporting the prosthesis in the compact form during delivery into the patient and constructed for expanding the prosthesis in contact with tissue. The portion includes a member positioned to engage the prosthesis near the distal end to maintain a corresponding portion of the prosthesis radially compact at a predetermined axial location, while proximal portions of the prosthesis are radially expanded to engage tissue. The portion of the prosthesis engaged by the member is releasable from the catheter at an axial location substantially corresponding to the predetermined location by relative axial motion between the member and the prosthesis, so the free end of the member disengages the prosthesis.
[0007] Embodiments may include one or more of the following features. The prosthesis has, near its distal end, an opening through the tissue-engaging body and the member extends generally along the axis of the catheter to a free end that engages the prostheses by extending through the opening and the portion of the prosthesis corresponding to the opening is released by axial motion so the free end of the member is removed from the opening. The opening may include a series of openings positioned around the circumference of the prosthesis and the member is a corresponding series of elongated members, which pass through the series of openings. The member extends distally to the free end so release of the prosthesis from the catheter is by moving the members proximally relative to the prosthesis. The member is fixed on the catheter so release of the prosthesis from the catheter is by moving the catheter relative to the prosthesis. The elongate member extends at an angle with respect to the axis of the catheter to form a predefined wedge space between the member and the catheter for engaging the prosthesis. The angle is about 3-8 degrees. The member is formed of a flexible material that deflects outwardly in response to a radial force, to release the free end of the member from the opening. The member is a superelastic wire. The length of the portion of the member passing through the opening is smaller than the expanded diameter of the prosthesis. The prosthesis is a tubular-form prosthesis positioned coaxially about the supporting portion of the catheter in the radially compact form. The prosthesis is formed of a patterned filament and the opening is formed by the pattern. The prosthesis is knitted and the opening is formed by knit-loops in the knit pattern. The opening is the end loop of the knit pattern. The prosthesis is self-expanding. Portions of the self-expanding prosthesis corresponding to the member are maintained in compact form by the member and portions remote from the member are maintained in compact form by a restraint. The restraint is an axially retractable sheath and the self-expanding prosthesis engages the sheath with substantial friction to place the prosthesis under tension as the sheath is retracted.
[0008] In another aspect, the invention features a system for positioning a prosthesis in contact with tissue on the wall of a lumen of a patient. The system includes a tubular prosthesis having a proximal and distal end and a tissue-engaging body therebetween. The prosthesis has a radially compact form for delivery into the patient and is radially expandable along its body for engaging tissue. The length of the prosthesis varies in dependence on expansion of the body. The prosthesis is formed of a patterned filament and includes a series of openings through the tissue-engaging body of the prosthesis about the circumference of the prosthesis, near the distal end. The system further includes a catheter having a portion for supporting the prosthesis coaxially about the portion in the compact form for delivery into the patient and constructed for expanding the prosthesis into contact with tissue. The portion includes a series of elongate members arranged about the circumference of the catheter, fixed to the catheter, and extending generally along the axis of the catheter to free ends positioned to pass through corresponding openings about the circumference of the tissue-engaging body of the prosthesis. The members maintain corresponding portions of the prosthesis radially compact at a predetermined axial location, while proximal portions of the prosthesis are radially expanded to engage tissue. The portion of the prosthesis corresponding to the openings is releasable from the catheter at an axial location substantially corresponding to the predetermined location by moving the catheter proximally so the free ends of the members are removed from the openings.
[0009] Embodiments may include one or more of the following features. The prosthesis is self-expanding and the elongate members in the openings maintain the distal end of the prosthesis compact after other portions of the prosthesis are radially expanded. The portions of the prosthesis proximal of the members are maintained compact by a retractable sheath. The prosthesis engages the sheath with substantial friction to place the prosthesis under tension as the sheath is retracted. The elongate members are formed of superelastic metal wires. The elongate members are formed of a flexible material that deflects outwardly in response to a radial force of expansion of the prosthesis to release the free ends of the members from the openings. The length of the portions of the elongated strands passing through the loops is smaller than the expanded diameter of the prosthesis. The elongated strands extend at an angle with respect to the axis of the catheter. The angle is about 3-8 degrees.
[0010] In another aspect, the invention features a system for positioning a self-expanding prosthesis in the body. The system includes a self-expanding prosthesis having a proximal end and a distal end and a tissue-engaging body therebetween. A catheter is provided having a portion supporting a prosthesis in a radially compact form. The portion of the catheter supporting the prosthesis includes a member positioned to engage the distal end of the prosthesis to maintain corresponding portions of the prosthesis compact at a predetermined axial location with respect to the catheter while other portions of the prosthesis are radially expanded to engage tissue. The system includes a retractable sheath positioned over and in contact with the prosthesis when the prosthesis is in the compact form. A tensioning element applies an axial force to the prosthesis to reduce frictional force between the sheath and the prosthesis while retracting the sheath to expose the prosthesis.
[0011] The sheath may be a restraining sheath that maintains portions of the prosthesis compact against the radial expansion force of the prosthesis and the tensioning element is formed by the sheath, engaged by the prosthesis with substantial frictional force to place the prosthesis under tension as the sheath is retracted.
[0012] In another aspect, the invention features methods of positioning a prosthesis in the body. For example, the method may include providing a system as described above, positioning the system in a body lumen with the distal end of the prosthesis in the compact form located substantially adjacent the axial location of the lumen wall corresponding to the desired distal extension of the prosthesis, expanding portions of the prosthesis proximal of the distal end to engage the wall of the lumen, and withdrawing the catheter proximally so the distal end is disengaged from the catheter and expanded against the lumen wall. The prosthesis may be positioned at a location adjacent a side duct branching from the lumen. The body lumen may be the bile duct. Many methods are evident from the description herein.
[0013] The advantages of the invention are numerous. For example, systems of the invention can provide accurate positioning of a prosthesis, even a self-expanding stent which changes its axial length upon expansion. Accurate positioning of the prosthesis is particularly important in cases where the portion of the body lumen to be treated is adjacent a tissue feature, such as another body lumen, that should not be occluded by the prosthesis. A tumor in the bile duct that is located adjacent the duodenum is one example. It is desirable to center the prosthesis about the tumor, but care must be taken so that the end of the prosthesis does not extend beyond the duodenum. Otherwise the motion of the body and the flow of food particles may drag the stent from the bile duct.
[0014] Further features and advantages follow.
BRIEF DESCRIPTION OF THE DRAWING
[0015] [0015]FIG. 1 is a side view, with a sheath in cross section, of a delivery system according to the invention;
[0016] [0016]FIG. 1 a is an enlarged perspective view, with the prosthesis partially cut-away, of the distal end of the system in FIG. 1 with the sheath partially retracted;
[0017] FIGS. 2 - 2 f illustrate the operation and use of the system in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] Structure
[0019] Referring to FIGS. 1 - 1 a, a system 2 according to the invention for delivering a prosthesis to the bile duct includes a catheter body 4 carrying a prosthesis 6 , which is held in a compact state for most of its length by a retractable restraining sheath 8 . The prosthesis 6 is a self-expanding knit-form stent having a series of end loops 10 . The distal end 14 of the catheter includes a series of flexible elongate members 16 running generally parallel to the axis of the catheter. One end of the members 16 is attached to the catheter body 4 . The other, free end 17 , of the members 16 extends through the end loops 10 , holding the end loops at a predetermined axial position and in compact form, even when proximal portions 18 of the stent 6 expand outwardly after retraction (arrow 20 ) of the sheath 8 . As will be discussed in further detail below, end loops 10 of the prosthesis 6 can be released from the catheter, and expanded against the lumen wall at a predetermined location, after most of the length of the stent has expanded to engage the lumen, by axially withdrawing the catheter body 4 so the free ends 17 of the members 16 slip back through the end loops 10 . In this manner, the end loops 10 are positioned at a defined location along the lumen wall, even though the self-expanding stent reduces its axial length upon radial expansion due to elastic rebounding effects and the loose knit nature of the structure. Moreover, sheath retraction is smoother since the stent is placed in tension by retraction of the sheath, which simultaneously reduces the axial force on the sheath wall.
[0020] The device 2 has an overall length L 1 , about 80 cm. The catheter body 4 (nylon) has a proximal portion 22 of constant diameter, about 0.11 inch, over a length, L 2 , of about 69 cm, and a distal portion 24 , which includes a taper 26 to a smaller diameter, about 0.053 inch, over a length, L 3 , about 1.0 cm. Following the taper 26 , a constant diameter portion 27 extends for a length, L 4 , about 10 cm, along which the stent 6 is positioned. The catheter body 4 further includes enlarged tip 30 (nylon with radiopaque filler) of length, L 5 , about 22 mm, maximum outer diameter 0.031 inch, with distal taper 32 (8-9 mm in length) for atraumatic advance, a step portion 33 (4 mm in length), which engages the sheath when the sheath is fully distally extended during entry into the body, and a proximal taper 34 (8-9 mm in length). A guidewire lumen 37 (phantom, FIG. 1), about 0.039 inch, for delivering the device over a guidewire, extends the length of the catheter body 4 , terminating distally at an end opening 39 in the enlarged tip 30 (FIG. 1 a ). The most proximal end of the body includes a luer lock device 7 . The catheter includes three radiopaque markers (tantalum bands). A proximal marker 9 indicates the proximal end of the stent in the compacted state. A central marker 11 indicates the proximal end of the stent in the expanded state. A distal marker 11 indicates the distal end of the stent. As will be discussed below, the distal marker 13 also deflects wires that form members 16 off the catheter body axis.
[0021] The stent is a self-expanding knitted stent, knitted of an elastic wire material (0.005 inch diameter), such as a superelastic nitinol-type material (e.g. Strecker stent®, Boston Scientific, Watertown, Mass.). The stent includes 40 rows along its length, with 8 knit loops in each row around the circumference. In the compact condition (FIG. 1), the outer diameter of the stent is about 2.8 mm, and the length, L 6 , about 10 cm. At full expansion, the stent has an outer diameter of 10 mm and shortens axially, to a length of about 6 cm. A feature of this invention is that the stent can be accurately positioned in spite of the axial length reduction on expansion, by maintaining the axial position of the distal end of the stent in the compact state, with members 16 , while allowing the proximal portions to radially expand and axially relax. After the variations at the proximal portions, the distal end is released from the members so it expands without substantial axial variation, and contacts the lumen wall at a predetermined location determined by axially aligning the radiopaque marker 13 .
[0022] The restraining sheath 8 (teflon), has a length, L 7 , about 60 cm and a wall thickness of about 0.006 inch. A handle 28 , located on portions of the sheath outside the body, is slid axially proximally to retract the sheath and expose the stent. As illustrated particularly in FIG. 1 a, the stent 6 engages the inner wall of the sheath 8 , owing to the elastic nature of the stent which causes it to push radially outward when in the compact state. A feature of the invention is that the sheath retraction is made easier and smoother. With only the distal end of the stent held axially in place by the members 16 , the friction between the inner wall of the sheath and the stent places the stent under tension during sheath retraction, which causes the stent to elastically elongate slightly. This tension reduces the radial force of the stent on the inner wall and also prevents the loops in adjacent knit rows from intertangling and bulging radially outwardly.
[0023] The members 16 are positioned equidistantly radially about the catheter 4 , with one member for each of the eight end loops of the stent. (only five members are visible in FIG. 1 a, the other three members being positioned on the opposite side of the catheter.) The members 16 are formed of straight wires (0.006 inch diameter) with an overall length of 13 mm. A proximal portion 15 , length, L 8 , about 4 mm, is attached to the catheter by a layer 19 of UV epoxy. (Another radiopaque band may cover the wires in the region between the epoxy and marker 13 and heat shrink tube may be used to cover the whole attachment assembly from epoxy 19 to marker 13 .) The portion of the catheter body distal of the epoxy includes radiopaque marker 13 , a tantalum band (about 0.060 inch wide) (Nobel Met, Inc., Roanoke, Va.), that creates a slight (0.003 inch) radial step from the catheter body, causing the normally straight wires to be deflected at an angle of about 3-8 degrees when the sheath is retracted. (With the sheath positioned over the wires, the free ends of the wires engage the inner wall of the sheath and the wires are bent inward slightly and partially supported against the proximal taper 34 of the enlarged end 30 .) The deflected portion of the wires extend beyond the marker 13 for a distance along the catheter axis, L 9 , about 6 mm to the free ends 17 . The deflection of the wires and the taper 34 of enlarged end 30 , create a predetermined space just distal of the marker 13 , slightly smaller in width than the diameter of the stent wire, where the end loops are positioned. As illustrated particularly in FIG. 1 a, the end loops are wedged in this space between the members 16 and taper 34 . In this position the end loops are maintained axially and radially stable when the sheath is retracted, but are also easily dislodgeable from the wedged position when the catheter body is moved proximally, after proximal portions of the stent have been expanded to engage the lumen wall. The angle of the members is about equal to the angle of the taper 34 (e.g. about 8°). (The angle of the members may be made larger than the angle of the back taper 34 so friction between the end loops and back taper is reduced as the catheter is withdrawn proximally.) In this embodiment, the end loops are wedged at a location toward the proximal end of the members 16 , about 1 mm from the radiopaque marker 13 . In this position, the radial expansion force of the stent does not overcome the stiffness of the wires and cause them to deflect outward and prematurely release the stent. When the catheter is slid proximally, the end loops are easily dislodged from the wedged location and slide along the members until the radial force overcomes the stiffness of the members, causing them to deflect outward, and the end loops are released. The length of the members is kept smaller than the expanded radius of the stent, yet long enough to hold the end loops compact. Further, the members are formed of an elastic material, such as a superelastic nitinol-type material, that does not plastically deform when the members deflect as the prosthesis is released or as the device is being delivered along a torturous path into a duct. Other embodiments can use filaments formed of other materials, for example, stiff polymers. Embodiments may also use filaments that have high stiffness and do not deflect under the radial expansion of the stent at any positioning of the end loops along their length, but rather, the end loops are removed only by the axial motion of the filaments. Systems such as described above can position the distal end of a stent within ±5 mm of a desired axial location, according to use in an operation such as described in the following.
[0024] Use and Operation
[0025] Referring now to FIGS. 2 - 2 f, use of the delivery system for positioning a stent in the bile duct is illustrated. Referring to FIG. 2, the system may be used to treat an obstruction 40 , such as a tumor, in the bile duct 42 . The bile duct extends from the liver 44 to the duodenum 48 . The system 2 is particularly useful for positioning a prosthesis in cases where the obstruction 40 is located near the duodenum 48 . In such cases, it is particularly important to position the distal end of the prosthesis so that the overlap with the duodenum is minimized. Otherwise the action of the duodenum may draw the prosthesis axially out of the bile duct into the intestine.
[0026] Typically, the occlusion substantially closes off the bile duct which has a healthy lumen diameter of about 8-10 mm. The obstruction is typically around 4 cm in length. To prepare the duct for the prosthesis, the physician accesses the liver with an access sheath 46 . A collangeogram is taken to locate the occlusion. Using ultrasound or fluoroscopy, a guidewire 49 (0.038 inch) is positioned through the access sheath, liver 44 and into the bile duct 42 , such that it crosses the lesion 40 and extends into the duodenum 48 . A series of dilators (not shown), for example, hard teflon, are tracked over the guidewire to widen the bile duct, tissue of a shoe leather-like texture, in preparation for the stent. The largest dilator approximates the full healthy lumen diameter. Alternatively, the largest dilator approximates the maximum outer diameter of the system with the prosthesis in the compact state. Balloon expansion devices can be used to the same effect before the system is positioned in the duct (or sometimes after the stent has been placed in the lumen). After preparing the lumen, the system 2 is tracked over the guidewire, through the sheath 46 , liver 44 , and into the bile duct 42 .
[0027] Referring to FIG. 2 a, the system is slid axially distally until distal radiopaque marker 13 is positioned axially at a location at least about 1 cm distal of the occlusion 40 . This location substantially corresponds to the position the distal end of the stent, when expanded, will engage the lumen wall. The location is selected so the stent 6 is positioned beyond the occlusion 40 but not too close to the end 47 of the bile duct. The marker 11 indicates the position of the proximal end of the stent in the expanded position and is such that the proximal end of the prosthesis will engage healthy tissue over a length of at least 1 cm. Where possible the stent is centered, based on the fully expanded length indicated by markers 11 , 13 , about the obstruction. The marker 9 indicates the proximal end of the stent when the stent is in the fully compact form, which has an overall length, L 6 , about 10 cm.
[0028] Referring to FIG. 2 b, the sheath is retracted in one continuous motion. (After the retraction begins in this embodiment, the sheath cannot be extended distally without catching on the expanded portions of the stent and possibly pushing the stent distally off of the members 16 .) With the sheath 8 partially withdrawn, (arrow 20 ), portions 18 of the prosthesis expand (arrow 21 ), although not to full expanded diameter. The end loops 10 of the prosthesis are maintained in the compact state and without axial movement, by the members 16 which deflect outward slightly (arrows 23 ) when the sheath is removed. With the distal end of the stent being held axially by members 16 , the friction between the inner wall of the sheath 8 and the portions of the prosthesis covered by the sheath places the stent under tension, causing the prosthesis to be elastically lengthened slightly (arrow 31 ) to a length, L 6 ′, about 10.2-10.4 cm. The lengthening of the prosthesis has a simultaneous effect of reducing the radial force the stent exerts on the wall of the sheath and, therefore, the frictional force between the inner wall of the sheath and the stent, allowing a smoother retraction of the sheath with less axial force.
[0029] Referring to FIG. 2 c, as the sheath retraction continues, proximally beyond about 60% of the distance between markers 9 and 13 , the frictional force between the stent and the wall of the sheath is overcome by the elastic forces of the stent, removing the tension on the stent, and causing the distal end of the stent to relax distally (arrow 23 ). As illustrated, the relaxation of the largely independent knit rows proceeds from distal portions to proximal portions, with more distal portions expanding (arrows 25 ) to full diameter and engaging tissue. The most distal end, including the end loops, remains compact and axially stable.
[0030] Referring to FIG. 2 d, after sheath retraction continues but usually to a point less than marker 9 , the proximal end of the expanding (arrows 25 ) and contracting (arrow 23 ) prosthesis exits the sheath and engages the lumen wall, forcing open the lumen to its normal diameter and firmly anchoring the stent so that it resists axial motion. (In some cases, the stent opens the lumen over an extended period of time.) The end loops 10 remain compact and axially stable, owing to the strands 16 , as the elastic forces relax during the expansion of the proximal portions. The stent in this condition has a shorter length, L 6 ″, about 6 cm.
[0031] Referring to FIG. 2 e, the prosthesis is released from the catheter by drawing the catheter proximally (arrow 27 ), which causes the end loops to be positioned at more distal positions along the members 16 , until the radial force of the prosthesis causes the members to deflect outwardly (arrows 29 ), releasing the end loops from the members on catheter body, so the end loops expand to full diameter. Since the stent has been substantially relaxed during expansion of proximal portions, the end loops engage the lumen wall at the desired axial location, without substantial elastic rebound axially. After the end loops are released from the members, the free ends of the members deflect back to their rest positions closer to the taper 34 .
[0032] Referring to FIG. 2 f, the catheter is then removed from the body, leaving the prosthesis properly positioned.
[0033] Other Embodiments
[0034] Many other embodiments are possible. Other types of stents, e.g., nonknitted stents, such as woven stents, can be used. The engagement of the distal end of the stent may be achieved by other arrangements, beside the openings in the stent wall and wires illustrated above. For example, the systems could include a separate member for holding the distal end of the stent axially and a separate member for holding the distal end of the stent radially compact. The separate members may be separately actuatable. While the systems discussed above provide particular advantages when positioning self-expanding stents in that sheath retraction is made easier, advantages, such as accurate placement, can be gained with other stents, such as non-self-expanding, plastically deformable type stents. The systems can be sized and configured for use in various body lumens, such as the biliary tree or blood vessels, or any other lumen where accurate location of a stent is desired, e.g., when the occlusion is adjacent a side branch.
[0035] Still other embodiments are in the following claims.
|
This invention provides smooth delivery and accurate positioning of prostheses in the body. In embodiments, systems are provided that include elongate members extending generally along the axis of a supporting catheter to a free ends. The elongate members extend through openings in the prosthesis to maintain the position of the prosthesis on the catheter. The prosthesis can be released from the catheter by relative axial motion of the catheter and the elongate members such that the free ends are removed from the openings in the prosthesis. In embodiments, the elongate members hold the distal end of a self-expanding stent at a desired axial location and in radial compaction as a restraining sheath is withdrawn. The friction between the sheath and stent puts the stent under tension, which reduces the radial force on the sheath wall, allowing smoother retraction. Proximal portions of the stent radially expand and axially shorten. The distal end, however, is maintained at the desired axial location and released from the catheter to contact the body lumen wall without substantial axial shortening.
| 0
|
Botanical classification: Tiarella cordifolia.
Varietal denomination: ‘Susquehanna’.
SUMMARY OF THE INVENTION
The new Tiarella cordifolia as selected during 2007 as a seedling from the garden at the Nursery of Sinclair A. Adam Jr. at Coatesville, Pa., U.S.A. The exact parentage of the new variety is unknown. It resulted from seedlings grown from open-pollinated plants of Tiarella cordifolia , and Tiarella cordifolia var. collina . Several hundred plants are grown for seed production, and some or all of these plants are likely included in the parentage of the new variety of the present invention.
The new variety has been carefully preserved and studied since the time of its discovery. Had such new variety not been discovered and preserved, it would have been lost to mankind.
It was found that the new Tiarella cordifolia , variety of the present invention exhibits the following combination of characteristics: (a) exhibits a compact mounding clump growth habit with substantial runners, (b) forms attractive white flowers on branched flower stalks, (c) forms lobed ovate green leaves having a matte finish during the summer that bear maroon markings primarily along the leaf veins maroon and this pigment expands in the late summer outward from along the veins. In fall the leaves turn darker red of variable intensity during the fall, but retain a green margin. and (d) is particularly well suited for growing as a distinctive ornamental ground cover, creating a dense stand in a season.
The new variety of the present invention can be readily distinguished from other previously known varieties of the species in view of the distinctive combination of characteristics discussed herein. The red, and green spring, summer, and fall color is considered to be particularly noteworthy.
The new variety well meets the needs of the horticultural industry and expands the choices of ornamental ground covers which fills in as a stand well. It performs well wherever a ground cover is desired, and is particularly well suited for use as a border planting, use in shaded areas, and for ecology and restoration casting open pollinated seedlings, and asexual runners.
The runners (stolons) and flower stems of clumps have been used to asexually propagate the new variety at Delhi, N.Y. (laboratory), and Coatesville, (breeder and nursery) Pa., U.S.A. It has been found that the distinctive combination of characteristics of the new variety is firmly fixed and is reliably transmitted to succeeding generations. During observations to date, the new variety has been found to be readily amenable to such propagation.
The new variety ‘Susquehanna’ can be compared to ‘Elizabeth Oliver’ (not patented), which differs from ‘Susquehanna’ in having foliage that turns purple rather than red with green margins in fall. ‘Susquehanna’ can also be compared to cultivars from the same breeding program, ‘Delaware’ (U.S. patent application Ser. No. 12/589,997), ‘Octoraro’ (U.S. patent application Ser. No. 12/589,995), and ‘Lehigh’ (U.S. patent application Ser. No. 12/589,998). ‘Delaware’ differs from ‘Susquehanna’ in having foliage that is less lobed. ‘Octoraro’ differs from ‘Susquehanna’ in having more pubescent foliage that is yellow in color in fall and in having flowers that are tinted pink in color. ‘Lehigh’ differs from ‘Susquehanna’ in having foliage that is less pubescent with more pointed lobes and in having more maroon markings between the veins.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 depicts a two year-old plant of ‘Susquehanna’ as grown in a garden in Baltimore, Md. in May. The plant parts depicted in FIG. 2 , FIG. 3 , and FIG. 4 were taken from a two year-old plant of ‘Susquehanna’ as grown in a garden in Coatsville, Pa. in May.
FIG. 1 : Shows a typical plant in bloom.
FIG. 2 : Shows the maturation of inflorescences with the least mature on the left and the most mature on the right.
FIG. 3 : Shows leaves in various stages of development.
FIG. 4 : Shows a stolon.
DETAILED DESCRIPTION
The following is a detailed description of the new variety that was obtained while observing plants being grown outdoors, and in the greenhouse during 2007-2008 at Coatesville, Pa., U.S.A. The plants were approximately two years of age and were being grown on their own roots. The chart used in the identification of color is The R.H.S. Colour Chart of The Royal Horticultural Society, London, England. More common color terms are to be accorded their ordinary dictionary significance.
Botanical classification: Tiarella cordifolia ‘Susquehanna’. Plant:
Habit.— Compact mounding clump, several runners. Type.— Evergreen. Height.— Approximately 15 to 20 cm without blooms, and approximately 25 to 30 cm with blooms. Width.— Approximately 30 cm. Stolons.— Greyed-Green Group 195A in color, surface is pubescent with hairs 0.5 to 2 mm in length, internode length 1.25 to 2 cm.
Foliage:
Type.— Simple. Shape.— Ovate to broadly ovate, palmately five-lobed (seven-lobed as the leaf expands) with an elongated central lobe, and irregularly crenate margins on all lobes having mucronate teeth. Each tooth has a small point, which is relatively firm with a leaf vein extending to the end of the tip. Length.— Approximately 9.5 to 12.1 cm. Width.— Approximately 8-11 cm. Margins.— Incised with dentation. Apex.— The lobes are broadly obtuse to rounded and cuspidate. Base.— Cordate. Texture.— Upper surface; Slightly rugose with a velvet matte finish with hairs about 2 mm in length and 2 to 3 mm apart with greater density on margins, lower surface; glabrous with hairs along the veins. Arrangement.— Basal clump, with branched runners 4-8 in number, usually 20 to 38 cm in length. Venation.— Palmately reticulate.
Young foliage: On the upper surface Yellow-Green Group 144A to 144B, and Greyed-Purple Group 187A at the center and along the main vein, and on the lower surface Yellow-Green Group 146B to 146C. Adult foliage: On the upper surface Green Group 137B to 137D, and Brown Group 200B at the center and along the main vein, and on the lower surface Yellow-Green Group 146B to Greyed-Green Group 191A. Fall foliage: Both the ventral leaf surface (upper) and the dorsal leaf surface (lower) are characterized by areas of light red and darker reddish-purple that are near and through the following colors: Red Group 49D and Red-Purple Group 62D in the lighter areas to Red Group 53D and Greyed-Purple Group 186B in the mid-tones to Greyed-Purple Group 187A and 187B in the darker areas. The dorsal leaf surface exhibits a slightly glossier appearance when compared to the more matte appearance of the ventral leaf surface that commonly is increased in expression in the autumn foliage.
Petiole.— The length commonly varies from approximately 9 to 15 cm, and the diameter commonly is approximately 2 to 3 mm, Yellow-Green Group N144D in color, surface is pubescent with hairs 0.5 mm to 2 mm in length.
Inflorescence:
Type.— Raceme and perfect (bisexual). Number.— Approximately 30 to 50 blooms per raceme. Bearing.— On a branched stalk commonly having a height of approximately 25 to 30 cm, with up to 2-3 short side branches. Side branches are 2-10 cm in length, bearing 5-10 blooms. Lastingness of inflorescence.— About 3 weeks. Flower buds.— Ellipsoid in shape, perigynous, 2 to 3 mm in depth and 2 mm in diameter, White Group 155B in color. Calyx.— Five-lobed, White Group 155B in color, 6 to 8 mm in diameter. Petals.— Five. Petal shape.— Triangular. Stamens.— Ten, 3 to 4 mm in length. Anthers Orange Group 27 D. Pistil.— One, 4 mm in length. Flower size.— Approximately 6 to 9 mm on average per floret. Color.— On the dorsal surface White Group 155B and on the ventral surface White Group 155A. Fragrance.— Slight and sweet. Pedicel.— Approximately 6 to 7 mm in length on average, Yellow-Green Group 146D in color.
Development:
Vegetation.— Clump-forming, with runners (stolons). Blooming.— Abundantly when initially blooms during May/June and sporadically thereafter during the summer and fall. Resistance to disease.— No susceptibility to diseases has been noted during observations to date. Hardiness.— Has proven to grow well in U.S.D.A. Hardiness Zones No. 4 to 7. Propensity to form fruit/seeds.— Approx 0.16 grams per (1 year old) plant (about 500 seeds).
Plants of the new ‘Susquehanna’ variety have not been observed under all possible environmental conditions to date. Accordingly, it is possible that the phenotype expression may vary somewhat with changes in light intensity and duration, cultural practices, and other environmental conditions.
|
A new and distinct Tiarella cordifolia plant characterized by its deep green foliage with deep purple markings and white blooms.
| 0
|
BACKGROUND OF THE INVENTION
[0001] The invention relates to a method as recited in the preamble of claim 1 . A prior art problem is often the excessive mouse travel required to activate functions. For example, an image measurement operation activated through a button on a toolbar may go as follows:
[0002] 1. Move cursor to button on toolbar
[0003] 2. Click on button to activate measurement function.
[0004] 3. Move cursor over image
[0005] 4. Perform graphics creation interaction on image.
[0006] Steps 1, 2 and 3 are required because a toolbar button must be pressed prior to graphics creation. In particular when performing multiple operations on images, continual cursor movements to and from menu-bars, toolbars and/or control panels become a nuisance. In the present invention, measurements may be made directly on the image so that the cursor need not travel to an edge of the image.
[0007] The distraction from on-screen toolbars and control panels increases with the amount of screen area reserved to such user interface constructs. Workstation screen area is scarce and should better be dedicated to essential information. For routine and diagnostic viewing this is displaying medical images. The invention does not rely on user interface constructs other than an on-screen region to display an image and associated graphics overlays.
[0008] The invention is based on an interaction model for routine medical image display, such as may be produced by CT, MRI, and various other present and future technologies. Particular features pertain to display, measurement and annotation functions for the image. Known organizations have many user interface items, such as icons, bars, and other. The present invention features in particular single mouse-button interactions. A few operations may use modifier keys. Most manipulations will directly affect images and associated overlay graphics. Control panels may be used to set preferences or default behaviour. Such control panels may be activated by pop-up menus. A few advanced applications augment the basic interactions by menus, toolbars or control panels. The model can comprehensively access viewing operations, such as in particular image measurements and image annotations.
SUMMARY TO THE INVENTION
[0009] In consequence, amongst other things, it is an object of the present invention to provide inherent manipulation of the images, without necessitating overlay items that would obscure the image. Now therefore, according to one of its aspects the invention is characterized according to the characterizing part of claim 1 .
[0010] The invention also relates to an apparatus that is arranged for implementing a method as claimed in claim 1 , and to a machine readable computer program for implementing a method as claimed in claim 1 . Feasible transfer media would be Internet and various types of data carriers, such as floppy disks. Further advantageous aspects of the invention are recited in dependent claims.
BRIEF DESCRIPTION OF THE DRAWING
[0011] These and further aspects and advantages of the invention will be discussed more in detail hereinafter with reference to the disclosure of preferred embodiments, and in particular with reference to the appended Figures that show:
[0012] [0012]FIG. 1, a medical imaging arrangement;
[0013] [0013]FIG. 2, an applicable image field;
[0014] [0014]FIG. 3, a pixel value measurement principle;
[0015] [0015]FIG. 4, a line measurement principle;
[0016] [0016]FIG. 5, an angle value measurement principle;
[0017] [0017]FIG. 6, a poly-line region-of-interest measurement principle;
[0018] [0018]FIG. 7, a freehand region-of-interest measurement principle;
[0019] [0019]FIG. 8, a poly-line curve measurement principle;
[0020] [0020]FIG. 9, a freehand measurement principle.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0021] [0021]FIG. 1 shows a medical imaging arrangement as pertaining to one or more conventional imaging technologies, such as CT, MRI, or other. The arrange has two image monitors 10 , 11 , a keyboard 13 , mouse 14 , and a processor provided with appropriate storage 15 . All these subsystems are interconnected through a suitable interconnection facility 16 that can be bus-based. I/O facility 12 interconnects to an outer world for receiving image data derived from the detection subsystem not shown for brevity, and for outputting of processed image data for long-term storage, hardcopying, and other. A user person may manipulate the image in various manners described hereinafter through mouse and/or keyboard actuations. Various other system configurations would be obvious to a person skilled in the art of image manipulating systems.
[0022] The invention uses simple mouse control: operation is foremostly controlled by a pointing device and a single button, sometimes enhanced by accelerators and/or modifiers. The invention is commonly comprehensive: it provides access to standard operations, but does not rule out any particular operation and may be adapted to specific requirements. The invention features the following operations:
Operation Description Point Pixel value measurements Distance Distance and pixel value profile measurements Angle Angle measurements Region-of-interest Area & pixel value statistics measurements Annotation Anchored and pointed image annotations
[0023] These represent various operations on images without basically amending the image itself. Now, FIG. 2 illustrates an image field, wherein various sensitive areas have been indicated as disclosed more in particular in the companion patent application PHNL000279EPP (ref.: ) that is herein incorporated by reference.
[0024] Since the present invention does not need screen area for extraneous user-interface constructs, diagnostic-viewing applications will emulate a conventional light-box by using screen area predominantly for image display.
[0025] Simple operation is essential for seldom-used applications. Many users get confused in a more complex environment. Providing a system controlled only by a mouse is motivated in that virtually all systems running viewing applications have a mouse which is a very cost effective device. However, other devices such as graphics tablets are feasible as well. The invention uses incremental graphics creation in that graphics objects associated with measurements and annotations are created by incrementally extending them to increasingly involved objects. These design principles are discussed further hereinafter.
[0026] Many applications provide graphics through toolbars with buttons dedicated to creating specific types of graphics objects. This approach suffers from being modal and interaction restricts to creating a single type of graphics object. Creating multiple types of graphics objects requires much mouse travel, moving the cursor to and from the toolbar.
[0027] Graphics objects used for measurements during routine viewing such as points, lines, angles and contours can be seen as being constructed from a sequence of points or drawn curves. This gives an incremental approach to graphics creation. A line is constructed from a point by adding a point, adding a point to a line forms an angle and a curve or contour is formed by entering a sequence of points. The type of graphics object being created is not defined up front but deduced from the number and or/topology of points entered during its creation. This avoids a modal interface since only one interaction creates all graphics objects.
[0028] Now, basic mouse interactions take one of two styles:
[0029] Click-Move-Click—The interaction is performed while no mouse button is pressed.
[0030] Press-Drag-Release—The interaction is performed while a mouse button is pressed.
[0031] Of these, the click-move-click style has the advantage that the actual mouse motion is performed without a mouse button being pressed, such enabling a finer control. The -press-drag-release style has the advantage that fewer mouse clicks are required.
[0032] Click-Move-Click
[0033] 1. Move cursor to interaction position. Appropriate cursor displayed
[0034] 2. Click mouse button. Optionally with one or more modifier keys.
[0035] 3. Move cursor over screen. Interaction takes place.
[0036] 4. Click mouse button.
[0037] Press-Drag-Release
[0038] 1. Move cursor to interaction position. Appropriate cursor displayed.
[0039] 2. Press mouse button. Optionally with one or more modifier keys.
[0040] 3. Drag cursor over screen. Interaction takes place.
[0041] 4. Release mouse button.
[0042] Which interaction actually takes place depends on the position at which the mouse interaction is initiated and which mouse buttons and modifier keys are pressed. The further disclosure presents the click-move-click style of mouse interaction. All interactions can be straightforwardly converted to the press-drag-release style.
[0043] Graphics
[0044] The following measurements and annotations are most common in diagnostic image viewing:
[0045] Point measurement measures the pixel-value and position of a selected point on the image.
[0046] Line measurement measures a distance between two selected points on an image, and optionally the pixel-value profile of the image along the line defined by the two points in a chart.
[0047] Angle measurement measures the angle formed by three selected points on the image and the distance between the successive pairs of points.
[0048] Curve measurement measures the distance along a curve drawn over the image. The curve may be drawn by hand or defined as a series of points connected by lines. Optionally, this can also display the pixel-value profile of the image along the curve in a chart.
[0049] Region-of-interest measurement finds the area and various pixel-value statistics of an image region. Optionally, this can display the pixel-value histogram of the region in a chart.
[0050] Anchored annotation displays a text annotation at a specific position on the image.
[0051] Pointed annotation displays a text with an arrow pointing at a specific point in the image.
[0052] Measurements and annotations are collectively called graphics. A specific graphic is either a measurement or an annotation. All graphics interactions are performed using a single mechanism. The basic interaction has the following steps:
[0053] 1. Move cursor to first point position.
[0054] 2. Click with shift modifier to mark first point on image.
[0055] 3. Move cursor to next point on image.
[0056] 4. Click to mark next point on image.
[0057] 5. Repeat steps 3 and 4 to define measurement graphic.
[0058] 6. Type text to enter annotation.
[0059] 7. Click to finish interaction.
[0060] Steps 3, 4 and 5 are only required if the graphics consist of multiple points. Step 6 is only required for defining an annotation. The graphics type of depends on the number of points used during the interaction, and on whether or not annotation text was entered, as illustrated by the following table:
Number of Points Text Shape Graphic 1 No Open Point 2 No Open Line 3 No Open Angle 4 . . . N No Open Curve 4 . . . N No Closed Region-of-interest 1 Yes Open Anchored annotation 2 . . . N Yes Open Pointed annotation
[0061] In the interaction model the user need not define what type of graphic is intended. The type is given by the actual interaction performed. This simplifies graphics creation by reducing the number of interactions and the amount of mouse travel. The following describes various graphic and detail typical interactions associated with their creation. The complete interaction model including various options is also presented.
[0062] [0062]FIG. 3 represents a pixel value measurement principle, wherein point measurements measure pixel values and positions at selected points in the image. For images wherein pixel values are calibrated, such as CT images, the pixel value is displayed in the corresponding pixel value scale. For non-calibrated pixel values, the pixel code value, often an unsigned integer value, is displayed. Images wherein distance is calibrated, such as CT and MR images or explicitly calibrated RF images, display the measurement position in millimeter coordinates. Non-distance-calibrated images display a measured position in pixel coordinate units. The interaction is as follows:
[0063] 1. Move cursor to point position; Cross Hair cursor is displayed.
[0064] 2. Click with shift modifier to mark point on image. Pixel-value and position displayed.
[0065] 3. Click to finish interaction.
[0066] Options are as follows.
Value Description Value Pixel value at point in image Position Position of point in image
[0067] [0067]FIG. 4 illustrates a line measurement principle to measure distances between pairs of image points. For images with calibrated distance such as CT and MR images or explicitly calibrated RF images, the value is displayed in a metric scale. For non-distance-calibrated images, the value is displayed in pixel co-ordinate units. Interaction is as follows:
[0068] 1. Move cursor to first point position; Cross Hair cursor is displayed.
[0069] 2. Click with shift modifier to mark first point in image; pixel-value and position displayed.
[0070] 3. Move cursor to second point position. Pixel-value and position display removed. Line pullout from first point to cursor and pullout distance displayed. Line pullout and distance updated as cursor is moved.
[0071] 4. Click to mark second point on image. Line pullout and pullout distance display removed. Line between first and second points and distance measurement displayed.
[0072] 5. Click to finish interaction.
[0073] Options
Value Description Distance Distance between points Profile Graph of pixel values along line
[0074] [0074]FIG. 5 shows a measurement principle for angle values between connected pairs of lines, and for distances between successive pairs of points on images. Images with known pixel aspect ratio have angle value displayed in degrees. Images with unknown pixel aspect ratio display no angle value. Images wherein distance is calibrated, such as CT and MR images or explicitly calibrated RF images, display distance values in a metric scale. Non-distance-calibrated images display distance values in pixel co-ordinate units. Interaction:
[0075] 1. Move cursor to first point position; Cross Hair cursor is displayed.
[0076] 2. Click with shift modifier to mark first point on image: pixel-value and position displayed.
[0077] 3. Move cursor to second point position. Pixel-value and position display removed. Line pullout from first point to cursor and pullout distance displayed. Line pullout and distance updated as cursor is moved.
[0078] 4. Click to mark second point on image. Line pullout and pullout distance displays removed. Line between first and second point and distance between first and second point displayed.
[0079] 5. Move cursor to third point position. Line pullout from second point to cursor, pullout distance and angle between line and pullout displayed. Line pullout, distance and angle updated as cursor is moved.
[0080] 6. Click to mark third point on image. Line pullout display, pullout distance and pullout angle display removed. Line between second and third point, distance between second and third point, and angle defined by first, second and third points displayed.
[0081] 7. Click to finish interaction.
Options Value Description Angle Angle between lines Distance Distances between successive points
[0082] Now, FIG. 6 illustrates a poly-line region-of-interest measurement principle, FIG. 7, a freehand region-of-interest measurement principle, FIG. 8, a poly-line curve measurement principle and FIG. 9, a freehand measurement principle.
[0083] In particular, curve measurements measure the distance along a curve drawn over the image. There are two curve forms, a poly-line, that is a series of control points connected by lines, and freehand, wherein begin and end control points are connected by a drawn curve. Defining a series of control points creates the poly-line form.
[0084] The freehand form is created by drawing over the required trajectory of the curve. The poly-line from can be edited through the positions of its control points. The freehand form is edited by redrawing portions of the curve.
[0085] For images in which distance is calibrated, such as CT and MR images or explicitly calibrated RF images, distance values are displayed in a metric scale. For non-distance-calibrated images, distance values are displayed in pixel co-ordinate units.
[0086] Poly-line interaction is as follows:
[0087] 1. Move cursor to first point position. Cross Hair cursor is displayed.
[0088] 2. Click with shift modifier to mark first point on image. Pixel-value and position displayed
[0089] 3. Move cursor to second point position. Pixel-value and position display removed. Line pullout from first point to cursor and pullout distance displayed. Line pullout and distance updated as cursor is moved.
[0090] 4. Click to mark second point on image. Line pullout display and pullout distance display removed. Line and distance between first and second point displayed.
[0091] 5. Move cursor to third point position. Line pullout from second point to cursor, pullout distance and angle between line and pullout displayed. Line pullout, distance and angle updated as cursor is moved.
[0092] 6. Click to mark third point on image. Line pullout display, pullout distance display and pullout angle display removed. Line between second and third point, distance between second and third point and angle defined by first, second and third points displayed.
[0093] 7. Move cursor to fourth point on image. Both distance displays and angle display removed. Line pullout from third to fourth points displayed.
[0094] 8. Click to mark fourth point on image. Line pullout display removed. Line between third and fourth points displayed.
[0095] 9. Move cursor to next point on image. Line pullout from last point to cursor displayed.
[0096] 10. Click to mark next point on image. Line pullout display removed. Line between previous and last points displayed.
[0097] 11. Repeat steps 9 and 10 to define all points on curve.
[0098] 12. Click to finish interaction. Sum of distances between successive curve points displayed.
[0099] Freehand interaction is as follows:
[0100] 1. Move cursor to begin point position. Cross Hair cursor is displayed.
[0101] 2. Click with control modifier to mark begin point on image.
[0102] 3. Move cursor over image. Curve is drawn under cursor as cursor is moved.
[0103] 4. Click to mark end point position. Distance along curve is displayed.
[0104] 5. Click to finish interaction.
Options Value Description Distance Distance along curve Profile Graph of pixel values along curve
[0105] Region-of-interest measurements determine area and pixel value statistics of a region defined by a closed curve drawn over the image. Just as with curve measurements there are two region-of-interest forms:
Form Description Poly-line Series of control points connected by lines. Freehand Control point on drawn contour.
[0106] Defining a series of control points creates the poly-line form. The freehand form is created by drawing over the required trajectory of the region-of-interest contour.
[0107] For images in which pixel values are calibrated, such as CT images, pixel value statistics are displayed in the corresponding pixel-value scale. For non-calibrated pixel values, statistics are displayed in pixel code values, often unsigned integer values.
[0108] The poly-line from can be edited simply by editing the positions of its control points. The freehand from is edited by redrawing portions of the curve.
[0109] For images in which distance is calibrated, such as CT and MR images or explicitly calibrated RF images, area values are displayed in a metric scale. For non-distance-calibrated images, area values are displayed in pixel co-ordinate units.
[0110] Poly-line interaction is as follows:
[0111] 1. Move cursor to first point position. CrossHair cursor is displayed.
[0112] 2. Click with shift modifier to mark first point on image. Pixel-value and position displayed
[0113] 3. Move cursor to second point position. Pixel-value and position display removed. Line pullout from first point to cursor, and pullout distance displayed. Line pullout and distance updated as cursor is moved.
[0114] 4. Click to mark second point on image. Line pullout and pullout distance display removed. Line between first and second point and distance between first and second point displayed.
[0115] 5. Move cursor to third point position. Line pullout from second point to cursor, pullout distance, and angle between line and pullout displayed. Line pullout, distance and angle updated as cursor is moved.
[0116] 6. Click to mark third point on image. Line pullout, pullout distance, and pullout angle display removed. Line between second and third point, distance between second and third point, and angle defined by first, second and third points displayed.
[0117] 7. Move cursor to fourth point on image. Both distances and angle display removed. Line pullout from third to fourth points displayed.
[0118] 8. Click to mark fourth point on image. Line pullout display removed. Line between third and fourth points displayed.
[0119] 9. Move cursor to next point on image. Line pullout from last point to cursor displayed.
[0120] 10. Click to mark next point on image. Line pullout display removed. Line between previous and last points displayed.
[0121] 11. Repeat steps 9 and 10 to define all points on curve.
[0122] 12. Move cursor to first point on curve. Line pullout from last point to cursor displayed.
[0123] 13. Click to close curve and finish interaction. Line pullout display removed. Line between last and first points, and area and pixel value statistics defined by region-of-interest displayed.
[0124] Freehand interaction is defined as follows:
[0125] 1. Move cursor to control point position. Cross Hair cursor is displayed.
[0126] 2. Click with control modifier to mark control point on image.
[0127] 3. Move cursor over image. Curve is drawn under cursor as cursor is moved.
[0128] 4. Move cursor over control point. Curve is closed to form contour of region-of-interest.
[0129] 5. Click to finish interaction. Area and pixel value statistics for region-of-interest displayed.
Options Value Description Area Area of region Average Average pixel value Deviation Standard deviation of pixel values Histogram Histogram of pixel values Maximum Maximum pixel value Minimum Minimum pixel value
[0130] Persons skilled in the art will recognize that the above disclosed method may be stored on a data carrier as a computer program that can effect of enhance an existing image processing machine to attain features of the present invention.
|
Cursor-based interaction on a computer-displayed medical image produces graphics related to information in the images in which successive locator positionings and/or actuations control both the geometry and the type of the graphics object. In particular, the state of the interaction is used to distinguish what type of graphics object is required. Various types of measurements are effected.
| 6
|
FIELD OF THE INVENTION
[0001] The invention relates to a self-contained hydraulic unit for use in small confined spaces. Specifically, a unit to perform inspection and repair of sewer pipe lines.
BACKGROUND OF THE INVENTION
[0002] There are currently many types of remotely controlled units that are designed to enter enclosed spaces, such as pipe lines, and perform intricate operations. For a pipe line such operations include inspection, cutting, measuring, and lateral installation. To perform the above operations it becomes necessary to have equipment that can enter the pipe and adjust (i.e. three degrees of motion) to line up with the desired location within the pipe. The majority of these units use electrical motors and gears, pneumatic power, hydraulic power, or a combination of the three to provide the motive force to obtain the degrees of actuation desired to perform the adjustments necessary for their application.
[0003] Currently, hydraulic systems have only been used on a limited scale due to excessive amount of hydraulic hoses needed to connect the unit to the above ground control system. For example, to actuate a hydraulic system with three dual acting cylinders there needs to be six hydraulic lines connecting the unit to the above ground control station. Since these units typically need to enter pipelines to a length of up to 500 feet the six lengths of hydraulic hose present numerous problems such as cost of hose, amount of hydraulic fluid needed in the reservoir, system pressure needed to overcome head loss throughout the hose, size of hose reels to handle the hose, and the increase in maintenance cost due to hose wear. Further, the remote unit, or its ancillary systems, must generate a considerable amount of forward motion to move itself and the six hoses down the enclosed space.
[0004] Additionally, depending on the enclosed space, typical hydraulic fluid may not be acceptable if accidentally released into the enclosed space. The addition of hoses being dragged long distances and the forces exerted on the couplings increase the risk of accidental release. Any spillage or leakage should be minimized or eliminated.
[0005] It is the object of this invention to provide a remotely controlled unit for the use inside pipe lines that employees a self enclosed hydraulic system allowing for the hydraulic actuation of at least three degrees of motion with the ability to receive attachments for measuring/inspecting, cutting lateral openings, and deploying lateral lining systems without having to connect hydraulic lines to an above ground control station. Additionally, the hydraulic system should run on environmentally safe (depending on the enclosed environment) hydraulic fluid.
SUMMARY OF THE INVENTION
[0006] Thus, described below is a unit with a self contained hydraulic system that allows at least 3 degrees of motion. The unit consists of the motor housing assembly, the rotational housing assembly, the clamp/camera assembly, and the control system.
[0007] The rotational housing assembly is positioned on the front of the unit and provides for the radial and rotational degrees of motion. The housing can be cylindrically shaped and can have a hydraulic rotary actuator mounted within the inner diameter of the housing with its shaft extending beyond the front of the housing. On the front end of the housing is mounted a rotational race. Attached to the rotational race are two mounting forks that in turn attach to the radial slide that is also keyed to the shaft of the rotary actuator. Pinned to the radial slide is an interfacing dovetail piston assembly that allows the extension of the dovetail piston assembly along the length of the slide. The mounting forks provide the reaction force to counteract the weight of the cantilevered attachments that can be attached to the dovetail and the moment force induced when attachments are extended to react with the side wall.
[0008] The motor housing is located directly behind the rotational housing. Like the rotational housing, the motor housing can be cylindrical. On the bottom front side of the housing can be mounted a dual rod linear hydraulic piston. The piston is attached to the rotational housing via a half moon linkage bolted to the rear bottom side of the rotational housing. This piston allows the rotational housing to be indexed along the axis of the unit with a range, in one embodiment, of approximately 4 inches. The remainder of the space inside of the motor housing contains the hydraulic system and the camera/laser power system. The hydraulic system consists of a motor/pump/reservoir power unit, solenoid actuated valves, tubing, and appropriate fittings. The camera/laser power system consists of two AC to DC power adapters with interfacing connections. In one embodiment, in the approximate middle of the motor housing there is an approximately 8 inch cut out in the housing that is capped off with a mounting plate upon which is mounted the clamp/camera assembly. On the bottom side of the motor housing is mounted two skis upon which the rotational housing slides and which interface with the sidewall of the pipe in which the unit is being used.
[0009] The clamp/camera assembly attaches to the mounting plate attached to the motor housing. The clamp consists of a hydraulic piston driven four bar linkage that is housed in a u-channel housing. On the portion of the four bar linkage that raises there is a horse shoe shaped camera bracket that provides mounting locations for an inspection camera. This design allows the camera to be retracted within the unit to protect it during the deployment of the unit into the pipe.
[0010] The unit is controlled through and electrical cable that is attached to a control box above ground. The key elements of the control box are two micro control boards, motor capacitor, power conditioner, and laptop computer. The laptop has the appropriate software to interface with the video cameras and the micro control boards allowing full control of all unit functions.
BRIEF DESCRIPTION OF THE DRAWING
[0011] The above and still further objects, features and advantages of the present invention will become apparent upon consideration of the following detailed description of a specific embodiment thereof, especially when taken in conjunction with the accompanying drawings wherein like reference numerals in the various figures are utilized to designate like components, and wherein:
[0012] FIG. 1 is a right side view of an embodiment of the unit showing internal components and the outer casing is in phantom;
[0013] FIG. 2 is a magnified front right perspective view of the Rotational Housing showing internal components and the interface of the radial piston with the t-slider and the rotary actuator;
[0014] FIG. 3 is a bottom view of the Rotational Housing showing internal components;
[0015] FIG. 4 is a schematic of the hydraulic system of the present invention;
[0016] FIG. 5 illustrates the unit attached to the control box;
[0017] FIG. 6 is a magnified view of the clamp assembly showing the internal components; and
[0018] FIG. 7 illustrates an embodiment of the unit functioning within an enclosed space.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Referring to FIGS. 1-7 , a unit 10 embodying the invention is illustrated. The unit 10 includes a motor housing 100 , a rotational housing 200 , a clamp housing 300 , and a control box 400 .
[0020] The motor housing 100 can be pipe shaped and has an internal diameter. Other embodiments can be shaped to fit the parameters of an enclosed environment. In this embodiment, the motor housing 100 is cylindrical to fit inside a pipe line. Mounted to the front of the motor housing 100 is an end cap 102 . The end cap 102 prevents interior components captured within the volume of the housing from exiting the housing. Mounted forward of the end cap 102 is a hydraulic power unit 104 . The hydraulic power unit 104 consists of a fluid reservoir 101 , a pump 103 , and motor 105 that form the hydraulic power unit 104 .
[0021] Forward of the hydraulic power unit 104 in a bottom 107 of the motor housing 100 are located a plurality of solenoid actuated valves 106 . Each solenoid actuated valve 106 consists of a valve body, two solenoids, and an interior cartridge. The solenoid actuated valves 106 are hydraulically coupled to the hydraulic power unit 104 . The solenoid actuated valves 106 are also hydraulically coupled to hydraulic cylinders 110 , 202 , 216 , and 310 .
[0022] At a front end 109 /bottom side 107 of the motor housing 100 a dual rod extend/retract piston 110 can be mounted to the rotational housing 200 . The dual rod extend/retract piston 110 can be attached to the rotational housing 200 by the rotational housing piston mount 204 and allows a horizontal extension or retraction of the rotational housing 200 while resisting the torque generated by the rotary actuator 202 . Thus, the rotational housing 200 is in front of the motor housing 100 .
[0023] FIGS. 2 and 3 illustrate that inside the rotational housing 200 is attached a rotary actuator mount 206 . A rotary actuator 202 is attached to the rotary actuator mount 206 with its keyed shaft protruding from the end of the rotational housing 200 . A rotational race 208 is attached to the front of the rotational housing 200 . A T-slider 214 is then slid onto and keyed to the shaft of the rotary actuator 202 . Mounted in the slots at each end of the T-slider 214 are forks 210 .
[0024] The slots on the end of the forks 210 in turn engage with the rotational race 208 securing the T-slider 214 on the shaft of the rotary actuator 202 and providing a resisting moment created by the actuation of the radial piston 216 . The radial piston 216 slides onto the T-slider 214 and a piston plunger 220 engages the tines 201 of the T-Slide 214 .
[0025] A piston cap 218 engages to a bottom of the radial piston 216 creating the seal needed for piston actuation. The front most side of the radial piston 216 contains a dovetail 203 that allows for the placement of attachments. In the current embodiment, attached is the lateral lining attachment 12 that allows the placement of a lateral lining system.
[0026] Attached to the bottom of the rotational housing are lift supports 222 that engage with skis 114 to prevent excessive torque on the extend and retract piston 110 rods. The skis 114 are mounted to the bottom of the motor housing 100 and can be used to center the unit 10 in the enclosed space, like a pipe, and providing a lateral slide surface for the rotational housing 200 .
[0027] The skis 114 are for one embodiment, other elements to assist in the unit traversing the enclosed space can be motorized or free-wheeling wheels, treads or any other type of propulsion. In one embodiment, the unit is “threaded” through the pipe line by the use of high strength cables attached to the front and rear of the unit 10 to pull the unit 10 in the forward and reverse directions in the pipe line or other enclosed space. Additionally, the hydraulic power unit 104 can be diverted to drive a linear propulsion system to drive the unit 10 .
[0028] FIG. 1 illustrates that in a space above the extend/retract piston 110 are located at least one DC power supply 112 . The DC power supply 112 supplies the power to the cameras 302 and other DC accessories. In the approximate middle of the motor housing 100 there is a cut-out 111 allowing the necessary space for the clamp housing 300 . The clamp mounting plate 108 is mounted to the motor housing 100 and in turn the clamp housing 300 is mounted to the clamp mounting plate 108 .
[0029] FIG. 6 illustrates that the clamp housing 300 houses the clamp assembly. The clamp assembly can include an L-linkage 308 , two long linkage arms 312 , two short linkage arms 314 , a barrel linkage 316 , a clamp piston 310 , a platform linkage 318 , a camera bracket 306 , and at least one camera 302 .
[0030] The clamp piston 310 can be mounted to the clamp housing 300 and the barrel linkage 316 can be threaded onto the plunger of the clamp piston 310 . The barrel linkage 316 has a round protrusion on each side that engages one side of each of the short linkage arm 314 . The other side of the short linkage arm is connected to the rear bottom hole of the L-linkage 308 . The rear top hole of the L-linkage 308 is connected to the rear top hole in the clamp housing 300 . The rear top hole of the platform linkage 318 is connected to the front hole of the L-linkage 308 and the front bottom hole of the platform linkage 318 is connected to the front of the two long arm linkages 312 . The rear holes of the two long arm linkages 312 are connected to the lower rear holes in the clamp housing 300 .
[0031] The camera bracket 306 is secured to the platform linkage 318 . The camera 302 is secured to the camera bracket 306 . By extending or retracting the clamp piston 310 , this four bar linkage allows the platform linkage 318 to be lowered or raised maintaining the camera bracket 306 level throughout the motion. The clamp is used to lock the unit into the pipe to resist any forces developed by the actuation of any of the degrees of motion.
[0032] In one embodiment, a clamp surface 304 sits atop platform linkage 318 and/or camera bracket 306 . The clamp surface 304 engages the upper surface of the enclosed space to anchor the unit 10 in place. Once the clamp surface 304 is engaged, the pressure to the clamp piston 310 can be fixed by closing its solenoid actuated valve 106 allowing a secure engagement. Once the unit 10 is ready for further travel along the pipe line, the clamp piston's 310 solenoid actuated valve 106 can be opened to allow disengagement.
[0033] In one embodiment, both the clamp surface 304 and the camera 302 are mounted to camera bracket 306 . When platform linkage 318 is actuated by the clamp piston 310 both the clamp surface 304 and the camera 302 can move at the same time. Once the movement on the camera stops, a technician operating the unit 10 can easily appreciate that the clamp surface 304 is engaged with the wall of the enclosed space or fully retracted into the clamp housing 300 .
[0034] All electrical components (i.e. motor, solenoids, D)C power supplies) are wired into a control cable 402 that is then connected to the control box 400 . The control box contains micro control boards that are controlled by a CPU (laptop 404 ) allowing the actuation of the self enclosed hydraulic system. See FIG. 5 .
[0035] Thus, the unit 10 requires a minimum of wires and no external hydraulic hoses to perform the necessary tasks inside the enclosed space. In a particular embodiment for entering the unit into a pipe line that is at least 8 inches in diameter, the unit 10 , as defined by the motor housing 100 can have an overall length of less than approximately 36 inches and approximately less than 6 inches in diameter not including the skis. In particular, the diameter can be approximately 5.5 inches in diameter. This allows the unit to enter a pipeline though a manhole cover, which are approximately 22 inches to 36 inches in diameter and the manhole proper typically expands to 48 inches to 60 inches near the pipe line. Further, the unit can be configured to enter pipe lines of any diameter, most particularly 8, 10, 12, and 16 inch diameter pipe.
[0036] In one embodiment, the hydraulic power unit 104 provides at least 25 psi hydraulic fluid to the hydraulic system. Each solenoid actuated valve 106 can be no bigger than 1.25×1.65×6.57 inches. The solenoid actuated valves 106 can all be 4 way 3 position valves allowing all of the hydraulic cylinders to be hydraulically actuated in both directions. The hydraulic power unit 104 , the solenoid actuated valves 106 , and the hydraulic cylinders can all be connected by 3/16 inch nylon tubing and compression fittings (see FIG. 4 ). Additionally, since an embodiment is designed to enter a pipe line, a hydraulic fluid to be used in the hydraulic power unit can be any biodegradable or food quality oil, including canola, vegetable, olive, sunflower and corn oils. Depending on the nature of the enclosed space, most non-compressible, non-corrosive, fluids can be used.
[0037] The hydraulic system described in FIG. 4 operates as follows: The hydraulic power 104 pumps hydraulic fluid into the supply line that is attached to port 1 on all of the solenoid actuated valves 106 . The solenoid actuated valves 106 are normally closed disallowing fluid to move through the ports. Upon actuation fluid flows from the supply line into port 1 and out of port 2 or 4 into the selected end of one of the hydraulic actuators 110 , 202 , 216 , or 310 . As the hydraulic actuator moves through its stroke, fluid is displaced out of the opposite side of the actuator. This fluid enters the solenoid actuated valve through port 2 or 4 and out of port 3 into the return line that returns the fluid back to the hydraulic power unit's 104 reservoir 101 .
[0038] The function of the unit operating in a sewer lining operation operates as follows, also see FIG. 7 :
[0039] The unit 10 is placed in pipe line and winched 18 using a tow cable 20 into a position, in this particular embodiment, the unit is positioned by a “lateral” connection 24 into a sewer pipe. A lateral connection 24 can enter the sewer pipe approximately anywhere within the top 180° arc of the sewer pipe. Once positioned, solenoid actuated valve 106 for the clamp piston 310 is actuated open and the clamp piston 310 extends, forcing clamp surface 304 to engage the surface of the sewer pipe and then the valve 106 is closed. Hydraulic power is now diverted to at least one of extend/retract piston 110 , the rotary actuator 202 , and the radial piston 216 . The combination of the movements allowed by the three interconnected pistons/actuators allows for three degrees of motion and permits the lateral lining attachment 12 to line up with the lateral 24 . Once the lateral lining attachment is lined up the solenoid actuated valves 106 are closed, locking the lateral lining attachment in place allowing the deployment of the lateral lining system.
[0040] While there have been shown, described, and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions, substitutions, and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit and scope of the invention. For example, it is expressly intended that all combinations of those elements and/or steps which perform substantially the same function, in substantially the same way, to achieve the same results are within the scope of the invention. Substitutions of elements from one described embodiment to another are also fully intended and contemplated. It is also to be understood that the drawings are not necessarily drawn to scale, but that they are merely conceptual in nature. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.
|
A remotely controlled unit providing three degrees of actuation (rotational, perpendicular to a long axis, parallel to a long axis) of a variety of attachments to assist in the inspection, measurement, lining, and repair of pipe lines. The degrees of actuation are accomplished using a hydraulic system having a hydraulic pump, reservoir, solenoid actuated automatic valves, pistons, and cylinders inside the body of the unit. The components are designed to operate in a partially to fully submersed environment. The unit has an on board camera system that allows an operator the ability to monitor the attachments. In addition to the degrees of actuation, the unit carries a hydraulic clamp that secures the robot in the pipe during its various operations. The unit is controlled and cameras viewed through a control cable that connects the unit to an above ground control station consisting of micro control boards controlled by a CPU.
| 5
|
BACKGROUND OF THE INVENTION
The present invention relates to a watercraft bucket for collecting floating materials.
It is known that the need to eliminate the causes of the pollution of waters, be they marine surfaces or inland waters of basins or rivers, is currently very urgent and strongly felt.
This need is all the more felt in recent times, due to a considerable algal florescence which occurs particularly in summer periods on the surface of the Adriatic sea and of the Venetian lagoon, causing considerable problems from the point of view of both navigation and bathing.
These algae furthermore form a film on the surface of the water which prevents the exchange of oxygen between the air and the water and ultimately causes havoc in the environment, preventing the life o aquatic flora and fauna.
SUMMARY OF THE INVENTION
The aim of the present invention is to provide a device which can collect algae or other floating materials and deposit them in a collection container.
A consequent primary object is to provide a device which is capable of separating the collected substances from the water.
Not least object is to provide a device which is structurally simple and easy to install.
This aim, these objects and others which will become apparent hereinafter are achieved by a watercraft bucket for collecting floating materials, characterized in that it comprises a loader which is arranged at the bow or in another position on the watercraft and is suitable for being arranged so that it is partially submerged during the advancement of said craft; said loader having a sieve-like bottom and a lower section configured like a depression chamber with at least one ejector suitable for expelling the conveyed water.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the invention will become apparent from the detailed description of an embodiment thereof, illustrated only by way of nonlimitative example in the accompanying drawings, wherein:
FIG. 1 is a schematic side view of a watercraft for collecting floating materials which is provided, at the bow, with the bucket according to the invention;
FIG. 2 is an enlarged side view of a detail of the watercraft of FIG. 1, with the bucket according to the invention;
FIG. 3 is a partially sectional perspective view of the bucket according to the invention;
FIG. 4 is a top view of the bucket according to the invention;
FIG. 5 is a view of a possible variation of the bucket according to the invention;
FIG. 6 is a schematic view of the bucket according to the invention, equipped with a device for separating oil-like substances from water.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the above FIGS. 1 to 4, the bucket according to the invention comprises a loader 1 having a lower section 6 and a rear wall and side walls extending upwardly from the lower section, and an open front. The loader bucket 1 is further provided with arms 2 which are articulated to a bow region of a watercraft 3 suitable for collecting floating materials.
Articulation is performed about a transverse axis so that the loader 1 can be overturned by suitable actuation means, according to the movements indicated by the broken lines in FIG. 2, parallel to the axis of the watercraft 3.
The loader 1 is suitable for being arranged so that its walls are partially submerged in front of the watercraft 3 during the advancement thereof and so that a surface portion of water is conveyed into it through the open front thereof.
In a region below the surface 4 of the water, said loader 1 is provided with a sieve-like bottom 5 which has its concavity directed upward and is constituted for example by a grille, by a net or by fabric.
The sieve-like bottom can conveniently be replaceable.
Beneath the bottom 5, the lower section 6 of the loader has a concave shape in which a double channel system defined below a plate extending from the loader bucket rear wall below the sieve bottom 5, 7 is defined at the rear; said channel system forms a sort of cylindrical depression chamber in which one or more ejectors 8 are installed; said ejectors are suitable for expelling the water, conveyed through a longitudinal opening extending between the edge of the plate and the lower section along the width of the lower section, out of two outlets of the cylindrical chamber laterally from the loader 1 or in any other direction.
Each of the ejectors 8 is conveniently constituted by a propeller 9 which is motorized by means of a variable-speed orientatable hydraulic motor 10.
Instead of being fixed, the blades of each propeller 9 can have a variable pitch so as to be able to vary the amount of expelled water as required.
As regards operation, both when the watercraft 3 is moving and when it is motionless with the loader 1 lowered, water and floating substances are conveyed into said loader.
The continuous expulsion performed by the ejectors 8 causes a concentration on the bottom 5 of substances which are subsequently discharged into the watercraft 3 by overturning the loader I.
As can be seen in FIGS. 2 and 3, a continuously- or discontinuously-moving, oleodynamically- or mechanically-actuated cutter 11 is fixed in front of the loader 1 for cutting the algae or other aquatic vegetation so as to facilitate the collection thereof by means of the bucket.
With reference now to the above FIG. 5, a variation of the bucket according to the invention provides a loader 101.
Said loader 101 differs from the preceding one in that the recovery of the material can occur with the simple movement and subsequent overturning of the internal sieve-like bottom 103 with independent arms 104 or with a continuous-discharge system which operates inside the bucket, for example by means of a conveyor belt.
A further variation illustrated in FIG. 6 is provided, inside the loader now designated by 201, above the sieve-like bottom 202, with a known unit 203 with partially submerged rotating disks for separating oil-like substances.
Conveniently, said disk unit 203 may also be arranged within the collection container arranged on the watercraft.
In practice it has thus been observed that the bucket according to the invention has achieved the intended aim and objects, since it is capable of collecting floating substances, such as algae or others, separating them from the water and then discharging them into a collection container.
The bucket is structurally simple and can thus be manufactured without particular problems.
The invention thus conceived is susceptible to numerous modifications and variations, all of which are within the scope of the inventive concept.
All the details may furthermore be replaced with other technically equivalent elements.
In practice, the materials employed, so long as compatible with the contingent use, as well as the dimensions, may be any according to the requirements.
|
Watercraft bucket including a loader which is arrangeable on the watercraft so that it is partially submerged under the water surface during the advancement thereof. The loader has a sieve-like bottom and a lower section configured like a depression chamber with at least one ejector which continuously expels the conveyed water.
| 1
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of International Application No. PCT/US2015/15615, filed on Feb. 12, 2015, which claims the benefit of priority under 35 U.S.C. §119 of U.S. Provisional Application No. 61/940,569 filed Feb. 17, 2014, the content of which is relied upon and incorporated herein by reference in their entirety.
BACKGROUND
[0002] One goal of the loose tube cable SZ stranding process is to impart as much helical length into the cable at the fastest possible speed. Reducing tube diameters may require smaller central members, which experience higher strains also cause a reduction in the helical “window” of the cable for a given lay length. Conventional loose tube cables have 6-8 turns between reversals, with a constant lay length between reversals. The reversal distances may vary somewhat based on machine technology, binder design, and processing speeds; however, the reversals naturally have a longer lay length. An average lay is typically calculated by the number of turns between reversals and the distance between reversals. This average lay is a function of the constant lay length in the helical sections, the number of turns, and the reversal distance.
SUMMARY
[0003] According to one aspect, additional helical length in the stranding process is input in the stranding process, facilitating the use smaller buffer tubes. In one embodiment, the strander rotates faster during selected sections of the RPM profile. For example, faster rotation could be used during typically constant rotational speed sections.
[0004] The speed limitations for SZ stranding is dominated by the time required to achieve the switch back. According to one aspect, the stranding speed can be kept at a first speed during stranding the switch back, and the stranding speed can be increased to a second speed during traditionally constant RPM portions of the lay. According to one aspect, it is possible to increase the helical window without reducing production speeds.
[0005] According to another aspect, tensile window is increased to enable smaller loose tube cables. It may thus be possible to, for example, to avoid the need to add yarns to a cable to reduce strain.
[0006] These and other advantages of the disclosure will be further understood and appreciated by those skilled in the art by reference to the following written specification, claims and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] A more complete understanding of the present disclosure may be had by reference to the following detailed description when taken in conjunction with the accompanying drawings, wherein:
[0008] FIG. 1 is a perspective view of an example SZ cable-stranding apparatus.
[0009] FIG. 2 is a perspective view of an example hollow-shaft motor showing an exploded view of a guide member attached to the hollow shaft via set screws.
[0010] FIG. 3 is a front-on view and FIG. 4 is a cross-sectional view of an example guide member of FIG. 2 in the form of a layplate having a central hole sized to pass the at least one core member, surrounding strand guide holes, and peripheral set-screw holes.
[0011] FIG. 5 is a schematic diagram of an electronic configuration of the SZ cable-stranding apparatus.
[0012] FIG. 6 is a schematic overall view of a SZ cable-forming system that includes the SZ cable-stranding apparatus.
[0013] FIG. 7 illustrates moderate increasing & decreasing of RPM.
[0014] FIG. 8 is an illustrative example in which lay length starts at a longer value at the reversal and continues to gradually tighten moving towards the mid-point of the helical section between reversals.
[0015] FIG. 9 illustrates the motor speed profile in a cable in which binders and water swellable tape may be omitted using a thin film extrusion.
[0016] FIG. 10 illustrates rotational angle.
[0017] FIG. 11 illustrates unwrapped SZ path.
[0018] FIG. 12 illustrates stranding angle.
[0019] FIG. 13 illustrates the shortest path along the inside of an SZ stranded buffer tube.
[0020] FIG. 14 illustrates path length comparisons inside an SZ stranded tube.
[0021] FIG. 15 illustrates SZ strain margin considering a single turn SZ reversal pattern and compared with the equivalent helical pattern.
DETAILED DESCRIPTION
[0022] Reference is now made to embodiments of the disclosure, exemplary embodiments of which are illustrated in the accompanying drawings. In the description below, like elements and components are assigned like reference numbers or symbols. Also, the terms “upstream” and “downstream” are relative to the direction in which the SZ-stranded cable is formed, starting upstream with the various unstranded strand elements and optional at least one core member, and ending downstream with the formed SZ-stranded assembly and SZ-stranded cable.
[0023] FIG. 1 is a perspective view of an example SZ cable-stranding apparatus (“apparatus”) 10 . Apparatus 10 has an upstream input end 11 and a downstream output end 13 . Apparatus 10 includes along an axis Al in order from an upstream to a downstream direction as indicated by arrow 12 , a stationary guide member 20 S and at least one hollow-shaft motor 100 that includes a rotatable guide member 20 R operably disposed therein. Here, the term “rotatable” refers to the fact that motor 100 causes the guide member to rotate, as described in greater detail below. FIG. 1 shows a configuration of apparatus 10 having a plurality of axially aligned motors 100 . An example type of motor 100 is a high-precision motor such as a servo motor. Adjacent motors 100 are spaced apart by respective distances S, which in many cases is governed by space constraints and the fact that larger guide-member separations result in lower tension variation in the strands. A typical spacing S between motors 100 is between 0.1 m and 2 m, and in an example embodiment the spacing is adjustable, as described below. The spacing S may be equal between all motors 100 , or equal between some motors, while in other embodiments the spacing S is not equal between any of the motors. Providing a variable spacing S between motors 100 may be used to adjust the stranding process. A large spacing downstream helps minimize tension variation while a short spacing upstream shortens the overall length of apparatus 10 with little impact on tension variation.
[0024] FIG. 2 is a perspective view of a motor 100 . Motor 100 includes a guide member driver in the form of a hollow shaft 102 defined by an axial shaft hole 104 formed therein. An example size of shaft hole 104 is between 1 and 3 inches in diameter, with 2 inches being a commonly available size suitable for use in forming many types of SZ cables. The term “hollow shaft” as used herein in connection with motor 100 is intended to include a motor that contains a through passage concentric with and contained within the rotating structure of the motor. For example, certain types of servo-motors suitable for use herein and discussed in greater detail below include inductively driven rotors that surround and drive a hollow shaft. Each motor 100 includes the aforementioned rotatable guide member 20 R operably disposed within shaft hole 104 (see FIG. 1 ) so that the guide member rotates with the rotation of the hollow shaft. A rotatable guide member 20 R is disposed in shaft hole 104 and is fixed to hollow shaft 102 by, for example, by set screws (as described below), an adhesive, a flexible or rigid mounting member or fixture, or other known fixing means.
[0025] Each motor 100 includes a position feedback device 106 , such as an optical encoder (see FIG. 5 , introduced and discussed below). Positional feedback device 106 provides information (in the form of an electrical signal S 3 ) about the rotational position and speed of hollow shaft 102 and thus rotatable guide member 20 R. An exemplary motor 100 for use in apparatus 10 is one of the model nos. CM-4000 hollow-shaft inductively driven servo motors made by Computer Optical Products, Inc., Chatsworth, Calif. Another exemplary motor 100 for use in apparatus 10 is a hollow-shaft gear-based motor, such as those available from Bodine Electric Company, Chicago, Ill.
[0026] FIG. 3 is a face-on view and FIG. 4 is a cross-sectional view of a guide member 20 that can be used as stationary guide member 20 S and/or as rotatable guide member 20 R. The guide member 20 is in the form of a round plate (“layplate”) having a central hole 24 with peripherally arranged smaller guide holes (e.g., eyelets) 28 (six guide holes are shown by way of example). Central hole 24 is sized to pass at least one core member 30 while guide holes 28 are sized to pass individual strand elements (“strands”) 40 . Core member 30 includes a strength element and/or a cable core member. One strength element is glass-reinforced plastic (GRP), steel or like strength elements presently used in SZ cables. Cable core members 30 include buffer tubes, optical fibers, optical fiber cables, conducting wires, insulating wires, and like core members presently used in SZ cables. Example strands 40 include optical fibers, buffer tubes, wires, thread, copper twisted pairs, etc.
[0027] Guide member 20 are arranged in apparatus 10 so that central hole 24 is centered on axis A 1 , and peripheral guide holes 28 are arranged symmetrically about the central hole. Guide member 20 is configured to maintain the at least one core member 30 and individual strands 40 in a locally spaced apart configuration as the core member and individual strands pass through their respective holes. Guide member 20 optionally includes hole liners 44 that line central hole 24 and/or guide holes 28 in a manner that facilitates the passing of core member 30 and/or strands 40 through the guide member. Hole liners 44 preferably have rounded edges that reduce the possibility of core member 30 and/or strands 40 from being snagged, abraded, nicked or cut as they pass through their respective holes.
[0028] With reference to FIG. 2 through FIG. 4 , rotatable guide member 20 R includes peripheral set-screw holes 25 , and hollow shaft 102 includes matching screw holes 25 ′ configured so that the rotatable guide member is attached to the hollow shaft via corresponding set screws 27 . Rotatable guide member 20 R is the same as or is similar to stationary guide member 20 S, and are both in the form of layplates such as shown in FIG. 3 and FIG. 4 . Motors 100 are axially aligned so that shaft hole 104 and the rotatable guide member 20 R operably disposed therein are centered on axis Al.
[0029] With reference again to FIG. 1 , the stationary guide member 20 S and each motor 100 are mounted to respective base fixtures 120 , which in turn are mounted to a common platform 130 , such as a base plate or tabletop. Base fixtures 120 are configured to be fixed in place to platform 130 , or positionally adjustable relative to platform 130 . The positional adjustability is achieved by slidably mounting base fixtures 120 to rails 140 , which allows for axial adjustability of each motor 100 . Movable motors 100 can be axially moved along rails 140 and placed together for “thread up,” i.e., threading the at least one core member 30 and strands 40 through their respective holes 24 and 28 in the various rotatable guide members 20 R, and then axially moved again along the rails to be spaced apart and fixed at select positions during the SZ stranding operation, as discussed below. The positional adjustability of motors 100 allows for the spacings S to be changed so that apparatus 10 can be reconfigured for forming different types of SZ cables or to tune the cable-forming process. Base fixtures 120 and platform 130 (and optional rails 140 ) are configured so that motors 100 can be added or removed from apparatus 10 .
[0030] With continuing reference to FIG. 1 and also to the schematic diagram of FIG. 5 , at least one servo driver 150 is electrically connected to the corresponding at least one motor 100 . Each servo driver 150 is in turn operably connected to a controller 160 . The controller 160 may include a processor 164 and a memory unit 166 , which constitutes a computer-readable medium for storing instructions, such as a rotation relationship embodied as an electronic gearing profile, to be carried out by the processor in controlling the operation of apparatus 10 . Apparatus 10 also includes a linespeed monitoring device 172 operably arranged to measure the speed at which the SZ-stranded assembly 226 or core member 30 travels through the apparatus. Example locations for linespeed monitoring device 172 include downstream of the most downstream motor 100 and adjacent SZ-stranded assembly 226 as shown, or upstream of stationary guide member 20 S and adjacent core member 30 . Intermediate locations can also be used. Linespeed monitoring device 172 is electrically connected to controller 160 and provides a linespeed signal SL thereto.
[0031] The controller 160 includes instructions (i.e., is programmed with instructions stored in memory unit 166 ) that control the rotational speed and the reversal of rotation of each motor 100 according to a rotation relationship. This rotation relationship between motors 100 is accomplished via motor control signals S 1 provided by controller 160 to the corresponding servo drivers 150 . The rotation relationship is embodied as electronic gearing. In response thereto, each servo driver 150 provides its corresponding motor 100 with a power signal S 2 that powers the motor and drives it at a select speed and rotation direction according to the rotation relationship. Position feedback device 106 provides a position signal S 3 that in an example embodiment includes incremental positional information, speed information, and an absolute (reference) position. The reference position is typically a start position of hollow shaft 102 , while the incremental position tracks its rotational position on a regular basis (e.g., 36,000 counts per rotation). The rotational speed of hollow shaft 102 is the change in rotational position with time and is obtained from the position information contained in signal S 3 . Linespeed signal SL provides linespeed information, which is useful for comparing to the rotational speeds of motors 100 to ensure that the rotational speed and linespeed are consistent with the operational parameters of apparatus 10 and the particular SZ-cable being fabricated.
[0032] For apparatus 10 having a plurality of motors 100 , each motor has a different rotational speed, with less rotational speed the farther upstream the motor resides. For an SZ stranded cable, the number n of “turns between reversals”' can vary, with a typical number being n=8. For this example number of turns between reversals, apparatus 10 starts at a neutral point (n=0) where all of the strands 30 and the rotational and stationary guide members 20 R and 20 S are aligned. Controller 160 , through the operation of servo drivers 150 , then causes motors 100 to execute four turns clockwise, and then reverse and execute eight turns counterclockwise. Note that after the first four counterclockwise turns, apparatus 10 returns to and then passes through the neutral point. After the eight counterclockwise turns, apparatus 10 reverses and performes eight clockwise turns. In this way, n=8 turns between reversals is obtained, with rotatable guide members 20 R turning four turns around the neutral point in each direction.
[0033] Rotation relationships for motors 100 are carried out in a similar manner for different numbers n of turns between reversals, a different total number m of motors, and a different maximum angular deviation θMAX between adjacent guide members. The number m of motors 100 needed in apparatus 10 generally depends on the type of SZ cable being formed and related factors, such as the maximum number n of turns between reversals, and θMAX, which in turn depends on the guide member diameter, the size of the core member 30 and the size of strands 40 . A typical number m of motors 100 ranges from 1 to 20, with between 5 and 12 being a common number for a wide range of SZ cable applications.
[0034] Apparatus 10 can be configured and operated in a number of ways. For example, rather than controller 160 controlling each individual servo driver 150 , in one embodiment the servo drivers are linked together via a communication line 178 and receive information about the rotation of the most downstream motor 100 via an electrical signal S 4 . The upstream servo drivers 150 then calculate the required motor signals S 2 needed to provide the appropriate rotation relationship (e.g., via electronic gearing) to their respective motors 100 . Thus, controller 160 transmits information via signal S 1 about the stranding profile (n turns between reversals, the laylength, etc.) to the first (i.e., most downstream) servo driver 150 . Each upstream servo driver 150 receives a master/slave profile (e.g. a gear ratio=R) for the motor 100 immediately in front of it via respective signals S 4 . Thus, the upstream servo drivers 150 are slaved to the most downstream servo driver. In this embodiment, controller 160 is mainly for initiating and then monitoring the operation of apparatus 10 . Linespeed information is provided to the most downstream servo driver 150 through controller 160 (i.e., from linespeed monitoring device 178 to controller 160 and then to the most downstream servo driver).
[0035] In a related embodiment, controller 160 transmits the aforementioned stranding profile information via signal S 1 to first servo driver 150 , while each upstream servo driver receives a master/slave profile (e.g. a gear ratio=R) that synchronizes them to the downstream servo driver. Since each upstream servo driver 150 is slaved to the most downstream servo driver, each servo driver requires the position feedback data from the first motor 100 . Linespeed information is provided to the first servo driver 150 through controller 160 .
[0036] In another related embodiment, controller 160 transmits the aforementioned stranding profile information to the first servo driver 150 . Controller 160 also calculates an individualized stranding profile for each upstream motor 100 based on the complete stranding profile that will result in a desired operation for apparatus 10 . In this case, there are no rotational master/slave relationships between motors 100 . Since each motor 100 operates independently of the others, each requires linespeed feedback from linespeed monitoring device 178 and only its own position information.
[0037] Thus, in one embodiment, each motor 100 is programmed to rotate with a select speed that is not necessarily slaved of off the “base” rotation ratio R. The rotation relationship between the motors has a non-linear form selected to optimize the SZ stranding process. The rotation relationship between two adjacent rotatable guide members 20 R can best be visualized as a function of the angular position θ M of a “master” guide member 20 R and the angular position θ s of a corresponding “slave” guide members. Thus, for a prior art mechanical system where the rotation ratio R is fixed, the angular position θ s of the slave guide member is determined by the function θ s =R*θ M , which is a linear function in θ. In contrast, the rotation relationship programmed into controller 160 can allow for a much more complex functional relationships between the angular positions and rotation speeds of guide members 20 . A non-linear rotation relationship is useful, for example, to minimize tension spikes that can occur during the SZ stranding operation.
[0038] FIG. 6 is a schematic diagram of an SZ cable-forming system (“system”) 200 that includes apparatus 10 of the present disclosure. System 200 includes strand storage containers 210 , typically in the form of spools or “packages” that respectively hold and pay off individual strands 40 and optionally one or more individual core members 30 . System 200 include a strand-guide device 220 arranged immediately downstream of strand storage containers 210 . Strand-guide device 220 may include a series of pulleys (not shown) that collect and distribute the strands 40 and the at least one core member 30 . SZ cable-stranding apparatus 10 is arranged immediately downstream of strand-guide device 220 and receives at its input end 11 the strands 40 and the at least one core member 30 outputted from the strand-guide device. Apparatus 10 then performs SZ-stranding of the strands about the at least one core member 30 , as described above. Strands 40 and the optional core member 30 exit apparatus 10 at output end 13 as an SZ-stranded assembly 226 , as shown in the close-up view of inset A of FIG. 6 (see also FIG. 1 ). SZ-stranded assembly 226 consists of strands 40 wound around the at least one core member 30 in an SZ configuration.
[0039] System 200 includes a coating unit 228 arranged immediately downstream of apparatus 10 . Coating unit includes an extrusion station 230 configured to receive the SZ-stranded assembly 226 and form a protective coating 229 thereon, as shown in the close-up view of inset B in FIG. 6 , thereby forming the final SZ cable 232 . In an example embodiment, extrusion station 230 includes a cross-head die (not shown) configured to combine the protective coating extrusion material with the SZ-stranded assembly. Coating unit 228 also includes a cooling and drying station 240 is arranged immediately downstream of extrusion station and cools and dries coating 228 . The final SZ cable 232 emerges from coating unit 228 and is received by a take-up unit 250 that tensions the SZ cable and winds it around a take-up spool 260 .
[0040] Apparatus 10 of the present disclosure eliminates the mechanical coupling between rotatable guide members 20 R and in this sense is a gearless and shaftless apparatus. Note that the strands 40 passing through the rotatable guide members 20 R do not establish a mechanical coupling between the guide members because the strands are not used to drive the rotation of the guide members. Without the added rotational inertia and bearing friction associated with mechanical components, faster reversal times and thus higher line speeds are possible for a given lay length. Gear-based SZ cable-stranding apparatus are also subject to extremely high dynamic loads during the reversals. This puts a great deal of stress on the power transmission gears, resulting in frequent maintenance issues. The gearless/shaftless SZ cable-stranding apparatus 10 eliminate these types of maintenance and reliability issues. Because the motion of rotatable guide members 20 R is electronically controlled, their rotational velocities in relation to other plates is programmable according to a rotation relationship to carry out rotation profiles (including complex rotation profiles) that result in smoother operation and lower tension variations on strands 40 and the at least on core member 30 .
[0041] FIG. 7 illustrates moderate increasing & decreasing of RPM during the traditional “constant speed” section of the RPM profile. This will create a variable helical length between reversals. The lay length of one turn is minimized mid-way between the reversals, and then gradually lengthens going towards the reversal. In the illustrated embodiment, L 1 <L 2 . FIG. 8 is an illustrative example in which lay length starts at a longer value at the reversal and continues to gradually tighten moving towards the mid-point of the helical section between reversals. If the sample in the figure were longer, the lay lengths would begin to increase approaching the next reversal off of the page.
[0042] According to one aspect of the present embodiments, there are benefits of the reversal which help to offset the elongation of the helical pitch at the reversal. The optimum could be in the range of 2-3 turns between reversals as compared to the standard of 8 today. The advantages may be optimal in cable designs using 8 turns; however, there are advantages even in the case of 2-3 turns between reversals.
[0043] RPM profile is limited by machine capability at the “reversal” portion of the RPM profile. According to one aspect, the strander can effect a gradual speed increase and then decrease during the traditional “flat” portions of the RPM profile. The strander may effect the gradual speed increase & decrease in the traditional “flat” portions of the RPM profile without any extra wear & tear on the equipment. The above aspect can be effected by the hollow shaft motor as discussed above with reference to FIGS. 1-6 . The capabilities of the above-described strander improve the ability to generate more helical window at a given line speed for any strander which is operating with 2+ turns between reversals.
[0044] According to another aspect, binders and water swellable tape may be omitted using a thin film extrusion. In one example, the following machine parameters are set for the rotation of the stranded: Maximum rotational speed of 3,000 rpm; Maximum rotational acceleration of 24,000 rad/s/s; and Number of turns between reversals of 4. FIG. 9 illustrates the motor speed profile. FIG. 10 illustrates rotational angle. FIG. 11 illustrates unwrapped SZ path. FIG. 12 illustrates stranding angle.
[0045] Referring to FIG. 13 , conventional design rules for strain window are derived for helically stranded tubes sometimes with an SZ adjustment factor determined empirically. It is possible to calculate the shortest path along the inside of an SZ stranded buffer tube by assuming the bundle is always in contact with the inside of the tube wall and the fiber bundle is able to move to the shortest path. The blue line is adjusted until it has the shortest length.
[0046] Referring to FIG. 14 , using numerical techniques it is possible to determine the shortest possible path inside an SZ stranded tube. This has been done for a range of different turn counts between reversals and an interesting conclusion can be drawn as shown in FIG. 14 .
[0047] Referring to FIG. 15 , considering a single turn SZ reversal pattern and comparing this with the equivalent helical pattern, there is a 52% increase in strain window from the profile that would typically be expected from the new direct drive strander. If the number of turns is now increased towards what we do currently, then the benefit reduces as shown in FIG. 15 .
[0048] It will be apparent to those skilled in the art that various modifications to the present embodiment of the disclosure as described herein can be made without departing from the spirit or scope of the disclosure as defined in the appended claims. Thus, the disclosure covers the modifications and variations provided they come within the scope of the appended claims and the equivalents thereto.
|
An optical cable includes a core member and a plurality of strands wound around the core member in an SZ configuration, the SZ configuration having at least two reversal sections and a helical section extending along a longitudinal length between the at least two reversal sections. A helical lay length of the wound strands is variable along the longitudinal length of the helical section. A method of forming an optical cable includes providing a core member and surrounding the core member with a plurality of strands by winding the strands in an SZ configuration that includes a helical section extending longitudinally between at least two reversal sections.
| 6
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a system for the secure communication of data. In particular it relates to the technique known as quantum cryptography. This is a technique suitable for use, for example, over an optical fibre LAN, or in an access network or a broadband optical telecommunications system.
2. Related Art
In quantum cryptography, data is encoded at the transmitter and decoded at the receiver using some specified algorithm which is assumed to be freely available to all users of the system, whether authorised or otherwise. The security of the system depends upon the key to the algorithm being available only to the authorised users. To this end, the key is distributed over a secure quantum channel, that is a channel carried by single-photon signals and exhibiting non-classical behaviour, as further discussed below. The transmitter and the receiver then communicate over a separate channel, known as the public channel, to compare the transmitted and received data. The presence of any eavesdropper intercepting the transmitted key results in a change in the statistics of the received data, and this change can be detected. Accordingly, in the absence of any such change in the statistics of the data, the key is known to be secure. The secret key thus established is then used in the encryption and decryption of subsequent communications between the transmitter and receiver. For added security, the existing key may periodically be replaced by a newly generated key.
In recent years considerable work has been directed to developing practical applications of quantum cryptographic techniques. For example, the present applicant's earlier International Application published as WO95/07582 discloses and claims a variety of multiple access networks using quantum cryptography for key distribution. As described in that application, the single-photon signals may be encoded using polarisation modulation, or using phase modulation. In the case of phase modulation, the preferred approach is to use a Mach-Zender configuration, in which a differential modulation is applied across a pair of transmission paths, and the outputs of the paths are combined interferometrically at the demodulator/detector. In practice only a single physical link is available between the transmitter and receiver, and so the two paths are time-multiplexed across the link by applying a delay to the signal corresponding to one of the transmission paths. This technique is described further in the paper by P. D. Townsend et al., “Secure optical communications systems using quantum cryptography”, Phil. Trans. R. Soc. Lond. A (1996) 354 805-817.
All quantum cryptography systems proposed or implemented to date, are inherently polarisation-sensitive. For laboratory-bench systems over relatively short links this is not a problem. However when it comes to practical implementations of the technology, using fibre links which may be 30 km or longer, then the polarisation sensitivity of the system presents considerable difficulties. Although optical signals may be injected into the link in a defined polarisation state, in passing through the link they are likely to undergo random changes in polarisation as a result of time varying temperature stress-induced birefringence, or other environmental factors. Since the receiver at the other end of the link is polarisation-sensitive, it has been necessary hitherto either to use active polarisation control to maintain a fixed polarisation state at the input to the receiver, or alternatively to substitute polarisation preserving optical fibre for standard optical fibre throughout the system. Either of these measures adds undesirably to the cost and/or complexity of the system.
SUMMARY OF THE INVENTION
According to a first aspect of the present invention, there is provided a method of communication using quantum cryptography comprising:
a) phase-modulating a single-photon signal;
b) transmitting the single-photon signal over a pair of time-multiplexed transmission paths;
c) transmitting with the original single-photon signal in each of the pair of time-multiplexed transmission paths a duplicate single-photon signal, which duplicate single-photon signal is modulated identically to the respective original single-photon signal and is polarised orthogonally with respect to the respective original single-photon signal;
d) combining interferometrically outputs of the time-multiplexed paths including contributions from both the original and the duplicate single-photon signals, and making thereby a polarisation-insensitive measurement.
The present invention provides for the first time a method of quantum cryptography which is inherently insensitive to variations in polarisation over the transmission link. This is achieved by transmitting over each of the time multiplexed transmission paths a pair of equally phase-modulated and orthogonally polarised pulses separated in the time domain, termed herein the “original” and “duplicate” pulses. These may be produced by replicating pulses from a single source, but the invention also encompasses implementations in which the “original” and “duplicate” pulses are derived from independent and possibly mutually incoherent sources. When the pair of pulses is resolved to provide a single measurement at the detector, the effects of any polarisation change on one of the pulses are compensated for by a complementary change in the contribution from the other of the pulses. This mechanism is described in further detail below. The invention makes possible the use of quantum cryptography without requiring polarisation preserving fibre for the transmission link or active polarisation control, whilst providing a bit error ratio across the link that remains generally stable and independent of environmental stresses. Accordingly, the invention makes possible a robust cost-effective and practical system using quantum cryptography to provide enhanced security.
Preferably the method includes a step of splitting the single-photon signal into two orthogonally polarised components subsequent to the step of phase modulating the single-photon signal, and selectively delaying one of the two components, thereby providing the separation in the time domain between the original and duplicate single-photon signals. A particularly efficient method of carrying out this step is by passing the single-photon signal through a length of polarisation maintaining fibre. If the fibre has its axis at 45 degrees to the plane of polarisation of the signal, then it will separate the signal into two orthogonally polarised components of equal amplitude which separate in time as they propagate through the PM fibre. Other techniques for producing the duplicate pulses are possible. For example, the duplicate signal may be taken from the unused second output port of the coupler on the output side of the transmitter.
Preferably, the separation in the time domain of the original and duplicate signals is less than the response time of a single-photon detector used in the step of demodulating and detecting the single-photon signal. When this is the case, then the detector will integrate the contributions from the two polarisation components without there being any further penalty in the signal-to-noise ratio.
Preferably the phase-modulated single-photon signals are output onto a multiple access network, and the step of demodulating and detecting is carried out for each of a plurality of users connected to the multiple access network.
With conventional techniques, the problems of polarisation control become particularly great in the context of multiple access systems where each of a number of receivers would require its own polarisation control system. Each of the receivers then has to go through an initialisation procedure to set the polarisation state appropriately at the outset, and has to maintain the polarisation state throughout the transmission on the quantum channel. Accordingly, the use of a system embodying the present invention is particularly advantageous in this context.
According to a second aspect of the present invention, there is provided a communications system using quantum cryptography comprising:
a) a source of single-photon signals;
b) a phase modulator for modulating the single-photon signals;
c) a pair of time-multiplexed transmission paths connecting the output of the phase modulator to a receiver;
d) means for transmitting with each original single photon signal in each respective time-multiplexed path a duplicate single photon signal which is separated in the time domain from the respective original single-photon signal, the duplicate single-photon signal being modulated identically to the original single photon signal and polarised orthogonally to the original single-photon signal; and
e) a demodulation and detection stage arranged to combine interferometrically outputs of the time-multiplexed transmission paths including contributions from both the original and duplicate single-photon signals to make a single polarisation-insensitive measurement.
According to a third aspect of the present invention, there is provided a signal for use in a quantum cryptographic communication system, the signal comprising original and duplicate single-photon signals which are separated from each other in the time domain, are identically modulated, and are mutually orthogonally polarised.
The invention also encompasses transmitter systems, and methods of operating transmitter systems, and receivers and methods of operating receivers.
BRIEF DESCRIPTION OF THE DRAWINGS
Systems embodying the present invention will be described in further detail by way of example only, and will be contrasted with the prior art, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic of a prior art communications system using quantum cryptography;
FIGS. 2 a and 2 b are graphs showing the output of the receiver in the system of FIG. 1;
FIGS. 3 a and 3 b are graphs showing the relationship between polarisation rotation and bit rate and bit error rate (BER);
FIG. 4 is a diagram illustrating the use of polarisation maintaining fibre to produce duplicate single-photon pulses;
FIG. 5 is a schematic of a first example of a system embodying the present invention;
FIG. 6 is a plot showing the signals on the transmission link in the system of FIG. 5;
FIG. 7 is a graph showing the output of the receiver in the system of FIG. 5;
FIG. 8 is a schematic of a second example of a system embodying the present invention;
FIG. 9 is a flow diagram for a method of communication using quantum cryptography;
FIG. 10 is a schematic of a further example of a system embodying the present invention;
FIG. 11 is a cross section of a substrate for use in a planar silica implementation of the invention;
FIG. 12 is a first example of a transmitter using a planar silica structure;
FIG. 13 is a second example of a transmitter using a planar silica structure;
FIG. 14 is a transmitter using a planar silica structure; and
FIG. 15 is a diagram showing part of a system incorporating two single-photon sources.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
As shown in FIG. 1, a conventional quantum cryptography system using a Mach-Zender configuration comprises a transmitter 1 and a receiver 2 linked by a transmission fibre 3 . The transmitter 1 includes a single-photon source, which in this example is provided by a laser 4 and attenuator 5 . Pulsed optical signals output by the laser 4 are attenuated by the attenuator 5 so that in each time slot there is in general no more than one, and on average significantly less than one photon. Alternatively, single-photon pulses might be obtained from a parametric amplifier source. Both types of source produce pulses exhibiting the required quantum properties, and the term “single-photon pulse” as used herein denotes all such pulses irrespective of how they are produced.
The single-photon pulses from the attenuated laser pass first through a 50/50 fibre coupler 6 which splits the pulse between the two arms of a modulator section 7 . One arm of the modulator section includes a phase modulator preceded by a polarisation controller. The latter is required if, as is typically the case, the modulator is polarisation-dependent. The other arm incorporates a short fibre loop to provide a time delay with respect to the first arm. This other arm also includes a polarisation controller 82 which is used to set light in that arm to a polarisation state orthogonal to that of the first arm. The two arms of the modulator sections are then coupled to the transmission fibre by a second 50/50 fibre coupler 9 .
At the receiver, a structure generally complementary to that of the transmitter is used. At the input to the receiver, a polarisation splitter 10 couples signals from the transmission fibre to the two arms of the receiver modulator section 11 . This includes, as in the transmitter, a polarisation controller and phase modulator pair in the arm which receives signals polarised in the reference plane, and a delay loop and a further polarisation controller in the other arm. The delay loop is equal in magnitude to the delay loop in the transmitter, and aligns in time the pulses from the two arms of the transmitter. At the same time, the polarisation controllers bring the signals in the two arms of the receiver into the same polarisation state. The signals from the two arms are then combined in a 50/50 coupler and interfere constructively or destructively depending upon the applied phase modulations. In the ideal case where the pulses have maintained their polarisation state over the transmission link this interference will be substantially complete (i.e. fringe visibility close to unity). The signal is output from one or other of the two output ports of the fibre coupler 14 . Individual detectors may be provided for each output port, but conveniently, as in this example, a single avalanche photo-diode may be used as the photo detector, with the two output branches separated in the time-domain using a further short delay loop.
The conventional system described above is inherently polarisation sensitive. In the receiver, the polarisation splitter divides signals between the two arms of the receiver according to their polarisation state, and applies a delay only in the branch receiving the leading pulses which were polarised in the direction orthogonal to the reference plane. If however the pulses experience a drift in polarisation state over the course of transmission through the link between the transmitter and the fibre, then a component of the leading pulse from the transmitter will enter the lower arm of the receiver, that is the arm without the delay loop, and so will appear at the output in advance of the main output signal. Similarly, as a result of polarisation drift, a component of the signal originally polarised parallel to the reference plane, that is to say the signal which was originally delayed in the transmitter, will appear in the receiver in the upper branch, that is to say the branch including the delay loop, and so will be further delayed. This component then appears in the output signal as a trailing side-peak following the main peak in the photon-count.
The effect of polarisation drift is illustrated in FIGS. 2 a and 2 b which show the output from the conventional system in both the ideal and non-ideal polarisation cases. The temporal data shows the detection events registered during the transmission of a random key sequence and the histograms show the average of one or many such transmissions. Each pulse generated by the APD starts a time interval measurement that is terminated by the first following clock pulse. As described in the applicant's copending international application WO 95/07582, the contents of which are incorporated herein by reference, prior to the transmission of signals on the quantum channel, a multi-photon synchronisation signal is communicated from the transmitter to the receiver. The system clock is in this way synchronised with the electrical pulse drive to the laser in the transmitter and hence photon detection events have well-defined intervals that lie in horizontal bands of width τ, where τ is the APD response time. The delay loop in the final multiplexer stage of the system ensures that photons arriving from the ‘0’ and ‘1’ output ports of the interferometer generate different interval values and hence can be temporally discriminated. APD dark counts are not synchronised with the laser source and hence generate random interval values. Dark counts that fall outside the photocount bands are rejected, however the proportion that fall inside the bands generate errors in the key transmission. In the ideal polarisation case shown in the upper graph of FIG. 2 a, all photons arriving at the receiver interfere and only two peaks are observed in the photocount histogram. In the non-ideal case, shown in the lower graph (FIG. 2 b ), many of the photons arrive in the non-interfering satellite peaks. The effect of polarisation drift is therefore to reduce the signal-to-noise ratio at the receiver by reducing the level of the main signal peaks and increasing the level of the side peaks. This can be a serious problem for a quantum cryptography system since the observed bit error rate is used as a measure of how much information has leaked to eavesdroppers. A high background error rate due to polarisation drift can limit the ability to detect eavesdroppers and hence compromise the security of the system. Moreover, the degradation in the signal at the receiver tends to vary randomly as the polarisation drift in the transmission link varies. Hence active polarisation control is required at the output of the transmission link as described in our above-cited copending international application.
In order to calculate the effect of the polarisation drift we use the following expression for the bit error rate ratio BER in the system:
BER =( Df +(1/2)(1- V ) PL η cos 2 θ)/( Df+PL η cos 2 θ)
where D is the number of counts per unit time due to detection noise, f is the fraction of those counts that fall within the photocount window, V(≈1) is the interference fringe visibility, P is the average number of photons per unit time leaving the transmitter, L is the system transmission coefficient due to loss in the fibre and optical components, and T is the detector quantum efficiency. The cosine term represents the magnitude of the pulse components falling within the main interference peak after polarisation drift parameterised by the angle θ. The two terms in the numerator represent the error rate caused by detector noise and imperfect fringe visibility respectively, and the denominator represents the total count rate in the detection windows which is the received bit rate for the system. The results are shown in FIG. 3 for parameter values of D=10 4 s −1 , f=5×10 −4 , V=0.98, P=10 5 s −1 , L=0.08 and η=0.12, which are representative of the experiment discussed by Marand and Townsend (Opt. Lett., 20, 1697 [1995]). As θ increases both the bit rate and the BER vary periodically. At the BER peaks the main photocount peaks shown in FIG. 2 will have disappeared, and all photons will be detected in the satellite peaks. Secure quantum key distribution can only be achieved with relatively low BER≦0.1, for example. Hence, without active polarisation control, it is evident that the conventional system will exhibit large fluctuations in key transmission rate and will periodically become insecure.
FIG. 4 illustrates a first example of a system embodying the present invention. By comparison with the conventional system, the transmitter is now modified in that the time-delayed pulse pair are now co-polarised and pass through a length of polarisation maintaining (PM) fibre before entering the transmission link. As shown in FIG. 5, the pulse pair are polarised at 45° to the fast and slow birefringent axes of the PM fibre and the different propagation speeds cause the orthogonal polarisation components of the pulses to separate in time. At 45° incidence, the two components are equal in magnitude, and so the overall effect on the error rate of any polarisation drift is substantially zero. At other angles of incidence, the two components differ in amplitude, and so the error rate shows some sensitivity to polarisation drift. As the angle moves away from 45° initially, in a system where the noise level is otherwise generally low, the effect is to reduce the effective bit rate. As the angle moves further away from 45°, then the error rate begins to increase sharply. This sensitivity increases until the angle of incidence is 0° or 90°, that is to say the plane of polarisation corresponds to one of the fast or slow axes of the fibre. Then, only a single component is transmitted, and so the sensitivity to polarisation drift is as great as that found in conventional systems. Preferably therefore, the angle between the axis of the fibre and the plane of polarisation of the input signal is 45° or, failing that, lies within the range from around 20° to 70°, and more preferably 35° to 55°. Preferably the secondary time delay t 2 is chosen to be less than the APD response time t d (typically 300-500 ps) but larger than the optical pulse width τ p -50 ps respectively. In most commercial PM fibre a delay of 150 ps could be obtained with ˜150 m of fibre. The primary time delay t 1 , will typically be in the range 500 ps-3 ns. Note that the polarisation reference plane indicated in FIG. 4 by the end of the // and ⊥ signs is rotated by 45° after the PM fibre.
Using the configuration described in the immediately preceding paragraph, there is now transmitted for each signal output from one or other of the arms of the transmitter, a pair of identically phase-modulated pulses separated by a short delay and in orthogonal polarisation states. The overall pattern of pulses output by the transmitter is therefore as shown in FIG. 6 .
At the receiver, no active polarisation control is now required. Instead the signals pass through a polariser and are then split between the two arms in the receiver by a 50/50 coupler. The photocount distribution for the system will appear similar to that illustrated in FIG. 2 for the non-ideal polarisation case in the conventional system. However, now the ratio of the main peak and satellite peak amplitudes is 2 for all output polarisation states from the transmission fibre. This can readily be seen by starting from the situation illustrated in FIG. 4 where one of the orthogonal pulse pairs (e.g. the leading pair) is completely blocked by the polariser at the input to the receiver. As the polarisation drifts the overall count rate stays constant, with the reduced contribution from the leading pulse pair compensated for by an increased contribution from the lagging pulse pair previously blocked by the polariser. Since the secondary delay between leading and lagging pairs t 2 is chosen to be less than the APD response time τ d the overall shape of the photocount peaks does not change. By keeping t 2 <τ d the photocount windows are maintained at their minimum values (i.e. t d ) and hence the signal-to-noise ratio is maximised. Note that in this system the key transmission rate and background error rate are now independent of any polarisation drift in the transmission fibre and hence no active polarisation control is required. The other polarisation controllers shown in FIG. 4 are static since the short lengths of fibre in the transmitter and receiver can in principle be isolated from any significant environmental perturbations. However, for more compact and stable configurations all the fibre in the transmitter and receiver could be replaced by polarisation-maintaining (PM) fibre or the whole structure could be fabricated from waveguides on a single planar silica chip (as discussed further below)
FIG. 10 illustrates another example of a system embodying the present invention. Instead of using PM fibre to duplicate the pulses, this embodiment takes a duplicate signal from the otherwise unused second output port of the 50/50 fibre coupler on the output side of the transmitter modulator section. The duplicate signal from the second output port is then passed through a branch 101 including a polarisation controller, which changes its polarisation state to be orthogonal to the original signal. The duplicate signal is then coupled back into the main signal path via a further 50/50 fibre coupler, with a short additional delay relative to the original signal. This additional delay provides the secondary delay t s .
In implementing the system described above, it is necessary to take account of the relative phase shifts of the pulses in the different polarisation states as they pass through different transmission paths. Each 50/50 fibre coupler gives a relative phase shift of π/2 for the two outputs. By adding up the number of cross-couplings for the two orthogonally polarised signals, and multiplying by π/2, it is found that the pulses polarised parallel to the reference plane have a relative phase shift due to the couplers of π while the orthogonally polarised pulses have a phase shift of 0. No further relative phase shift is introduced in the receiver. This means that when interference is constructive for the parallel-polarised pair it is destructive for the orthogonally polarised pair. Accordingly, as shown in FIG. 7, it is necessary to discriminate the two peaks due to the parallel and orthogonal pairs respectively, and to invert the key data carried by the parallel channel with respect to the data carried by the orthogonal channel.
The technology used to implement the system may be generally similar to that described in our above-cited international application. In particular, the transmitter source may comprise a gain-switched semiconductor laser, which may be a DFB or Fabry Perot device and an attenuator. The single-photon detector in the receiver may be an avalanche photo diode (APD) biased beyond breakdown and operating in the Geiger mode with passive quenching, as discussed in PD Townsend et al, Electronics Letters 29, 634 (1993). Silicon APDs such as the SPCM-100-PQ (GE Canada Electro Optics) can be used in the 400-1060 nm wavelength range, while germanium or InGaAs devices such as the NDL 5102p or NDL5500p (NEC) can be used in the 1000-1550 nm range. As shown in FIG. 8 the receiver may also include a microprocessor control unit which receives the output of the APD via a discriminator/amplifier circuit, and where appropriate, inverts the bit values. The control unit may also include an electronic filter 84 and local oscillator 85 as well as an APD bias supply. The electronic filter is used to isolate the first harmonic of the frequency spectrum of a signal output by the APD in response to a synchronising pulse transmitted over the transmission link. This generates a sinusoidal signal at the pulse frequency which is used to lock the local oscillator. The output of the local oscillator is received at the control unit 82 to provide a timing reference for the quantum transmissions.
The phase modulators in the transmitter and receiver are lithium niobate or semiconductor phase modulators operating at, eg, 1-10 MHz. An appropriate lithium niobate device is available commercially as IOC PM1300.
A suitable polarisation controller for use in the transmitter and receiver, and, in the last of the above examples, for use in the branch used to generate the orthogonal pulses separated by the secondary delay interval, is that available commercially as BT&D/HP MCP1000. The 50/50 couplers are fused-fibre devices available commercially from SIFAM as model P22S13AA50.
The transmitter and receiver structures may be fabricated using monolithic or hybrid integration techniques. This approach uses semi-conductor micro-fabrication techniques to combine all the required components onto a single compact device or chip. The stability of the devices will be also improved and the cost of manufacture potentially greatly reduced. The planar waveguide structures required to define the optical paths in the transmitter and receiver may be based on semiconductors e.g. Si or InGaAsP alloys, glass, LiNiO3, or some hybrid structure. FIG. 11 shows the cross-section of a silica glass waveguide fabricated on a silicon substrate, which would be a promising candidate for this application. The structure comprises an SiO 2 core 110 , SiO 2 cladding 111 and the silicon substrate 112 . In this structure the refractive indices of the SiO2 waveguide core and cladding regions are controlled by the inclusion of dopants such as, for example, P, Bo or Ge during deposition. Appropriate planar silica fabrication techniques and device structures are reviewed by M. Kawachi in Optical and Quantum Electronics, 22, 391 (1990) and by T. Miyashita et al in SPIE volume 993, Integrated Optical Engineering VI (1988).
Embodiments of the transmitter and receiver structures based on planar waveguide structures are illustrated in FIGS. 12, 13 , 14 . In the transmitters, the laser and absorption modulator may either be coupled directly to the waveguide structure, as shown, or remotely located and linked by a fibre. Alternatively, in a semiconductor-based structure these components may be fabricated directly into the planar chip. The absorption modulator, which may consist of one or more semiconductor electro-absorption devices, can be used as an external modulator for generating pulses from a cw laser source and also for controlling the average photon number of the pulses leaving the receiver (typically ˜0.1). If the planar structures are fabricated using silica waveguides then the active phase modulators can utilise either the thermo-optic effect, or the electro-optic effect which can be made non-zero in glass by electric field poling (see e.g. X.-C. Long et al., Photonics Technology Letters, 8, 227 [1996]). In the former case the phase modulator drive electrode takes the form of a thin-film heater and the device is likely to have a maximum operating frequency of ˜10 kHz, limited by the thermal conductivity of the waveguide and substrate materials. Poled devices, on the other hand, in which phase modulation is generated via an applied electric field offer the prospect of much higher operating frequencies >1 GHz. Alternatively, the waveguides may be fabricated from a semiconductor such as Si, and in this case the refractive index changes required for phase modulation may be generated by changing the carrier population in an electrically active device fabricated on or near one of waveguides. The transmitter shown in FIG. 12 uses an external length of PM fibre to separate the output pulses into two orthogonally polarised and time delayed channels as discussed above for the first fibre-based embodiment. In FIG. 12 the other components illustrated comprise a laser 121 , absorption modulator 122 Y coupler 125 , delay loop 124 and electrode 123 . In the transmitter shown in FIG. 13, instead of using an external PM fibre, this function is carried out on the planar waveguide chip itself by means of an additional delay stage containing a polarisation mode converter 130 (TE/TM or TM/TE) in one arm. TE/TM mode conversion has been demonstrated in LiNiO 3 waveguide structures and polarisation modulators based on the effect are commercially available as model AOPC-1310/1550 from E-Tek Dynamics Inc. The receiver shown in FIG. 14 has a structure complementary to that of the transmitters apart from the inclusion of a polariser in the input waveguide. The polariser 140 can be fabricated as a metal film overlay that is sufficiently close to the waveguide core for coupling to a plasmon mode of the metal to occur. This coupling is highly polarisation selective such that one of the orthogonal modes is strongly attenuated. Polarisers based on this effect are currently commercially available from Sifam as model SP13/15. The APD detectors 144 can be mounted directly on the waveguide outputs of the interferometer as shown in FIG. 14 or alternatively an additional waveguide delay stage may be included on the chip such that a single APD may be used as in the fibre-based embodiment discussed above. The device of FIG. 14 also includes electrode 142 , delay loop 141 and directional coupler 143 .
As noted in the summary of the invention above, the invention may be implemented by a system using a pair of single-photons sources which may be incoherent. This arrangement is shown in FIG. 15 . In this scheme, the secondary delay, that is the delay between the original and duplicate pulses, is set by the path length difference between the two sources. That is to say, the secondary delay is determined by the difference in length between a first input branch 152 connected to laser 4 and a second input branch 151 which is connected to laser 20 . The phase modulator in one of the transmitter arms must be polarisation independent. Both of the input branches include attenuators 150 . When such a transmitter structure is used, then the receiver may have the same layout as the conventional receiver shown in FIG. 1 . It includes at its input a polarisation splitter, rather than a polariser filter preceding a 50/50 coupler as in others of the embodiments described above.
Although, for ease of illustration, the, examples described so far use a simple point-to-point link, the present invention is by no means limited to use in this manner, and in practice may often be used over multiple access networks such as those described in our above-cited co-pending international application. FIG. 8 shows one example of a network having a tree structure linking a transmitter to two receivers at different locations on the network. As discussed in our earlier application, the single-photon signals branch randomly on the network and this behaviour is used to establish different respective keys for the different receivers. A polarisation filter PF is used at the input to the or each receiver to resolve the two different polarisation components in a manner analogous to the operation of the polarisation splitter in the first example.
After the passing of single-photon signals between the transmitter and the or each receiver, the transmitter and receivers) enter a public discussion phase in which individual single-photon signals and their sent and received states are identified by means of the time-slot in which they were detected and transmitted. At the end of this process the transmitter and the or each receiver are in possession of a mutually secret key. Where there is more than one receiver on the network, then, except with a small probability which can be reduced arbitrarily close to zero by privacy amplification, each terminal has no knowledge of any other key apart from its own.
After this public discussion phase, the keys can be used to encrypt securely data transmission between the transmitter and the or each receiver.
The public discussion stage described above may be carried out over the same network, possibly using bright multi-photon signals, or over a separate and independent communication channel. Privacy amplification is a procedure described in the paper by C H Bennet et al “Experimental Quantum Cryptography”, J. Cryptography, 5, 3 (1992). Privacy amplification ensures that the transmitter and receiver end up with identical keys, and the any key information leaked to an eavesdropper or to another terminal is an arbitrarily small fraction of one bit. The different stages outlined above can be summarised as follows:
(i) Transmitter (Alice) and receiver (Bob) perform raw transmission and discard bits from different bases.
(ii) Public comparison of randomly-selected sample and estimation of error rate.
(iii) Public error correction procedure producing error-corrected key.
(iv) Estimation of how much information eavesdropper (Eve) may have about the key.
(v) Privacy amplification to distil a final secret key about which Eve has negligible information.
Stage ii might optionally be omitted, since the error rate may also be determined in step iii. In the examples discussed above, the statistic used to determine the presence or absence of an eavesdropper may be simply the error rate as determined in stage ii and/or iii. This is then compared with a predetermined threshold level. However, other more complex statistics may be used. For example, as described in our copending application WO 96/06491, coincidence detection may be used. At its simplest, the statistical test may simply check that the count rate is not significantly lower than that expected.
FIG. 9 is a flow diagram showing the above stages and the data flow between the transmitter (Alice) and the receiver (Bob).
|
A communication system uses quantum cryptography for the secure distribution of a key. A single-photon signal is phase-modulated and transmitted over a pair of time-multiplexed transmission paths. With each original single-photon signal in a given one of the transmission paths, a duplicate signal is transmitted. The duplicate is identically modulated and orthogonally polarized. At the receiver, the outputs of the two paths are combined interferometrically. A single polarization-insensitive measurement is derived from the combined contributions of the orthogonally polarized signals.
| 7
|
BACKGROUND
[0001] 1. Technical Field
[0002] The invention relates generally to vacuum microelectronic circuitry implementations; and, more particularly, it relates to implementations of vacuum microelectronic circuitry that is used to perform twisted pair termination applications.
[0003] 2. Related Art
[0004] Conventional approaches to provide varying services to subscribers are geared towards physical provision of hardware on a customer by customer basis. For example, in the context of providing digital subscriber line (DSL) service to a new customer, a common approach is to first disconnect any existing service to that customer, then performing a re-connect to a plain old telephone service/system (POTS) chassis, then connecting the POTS chassis to a DSL enabled modem, and finally connecting the POTS chassis to a class 5 switch. Each and every one of these functions requires a re-configuration of hardware to meet this customer's new needs. This can prove extremely costly in terms of man hours and hardware. Even changing from a relatively higher end service such as integrated services digital network (ISDN) to digital subscriber line (DSL) service also requires this physical re-configuration for provision of the new service. There does not exist in the art an integrated system to avoid this manual reconfiguration between various services.
[0005] Moreover, the current state of many conventional switching technologies prohibits their implementation within central offices and/or switching stations, given their large size and extremely high consumption of real estate within the circuitries and boards employed to perform such applications.
[0006] In addition, the conventional implementations that employ discrete components to perform a variety of functions including lightning protection, transformer functions, analog front end, and line driver functions using discrete solid state devices inherently leads to a low density of components on a given board or within a given application. The conventional approach of physically re-configuring the system to accommodate the various services to be provided within a substantially diverse customer base inherently leads to this disjointed and discrete device implementation approach.
[0007] A fundamental drawback of active electronic devices based on silicon is that electron transport is impeded by the silicon crystal lattice, which places a limit on both the miniaturization and the switching speed of such devices. A solution to this is to create an active electronic device which relies on electron transport through vacuum. Such devices come under the umbrella of a field of microelectronics known as vacuum microelectronics, the interest in which has grown greatly over the last few years, largely fed by the prospect of their use to make flat-screen displays.
[0008] Integrated vacuum microelectronic triodes have been fabricated on silicon using micromaching to yield an emitting cathode tip made from silicon which lies beneath a self-aligned gate and anode. The anode electrode is suspended across the emitting tip, and the gate approaches from the sides; both are supported on an insulating layer of thick silicon dioxide. The device operates in the normally-on mode: the anode is biased positively until a large stable emission current is obtained, and the gate is biased negatively to turn the device off. D.M. Garner and G. A. J. Amaratunga, “VACUUM MICROELECTRONIC DEVICES,” Department of Engineering, University of Cambridge.
[0009] Further limitations and disadvantages of conventional and traditional systems will become apparent to one of skill in the art through comparison of such systems with the invention as set forth in the remainder of the present application with reference to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] A better understanding of the invention can be obtained when the following detailed description of various exemplary embodiments is considered in conjunction with the following drawings.
[0011] [0011]FIG. 1 is a system diagram illustrating an embodiment of a subscriber network that is built in accordance with certain aspects of the invention.
[0012] [0012]FIG. 2 is a system diagram illustrating an embodiment of a multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0013] [0013]FIG. 3 is a system diagram illustrating an embodiment of a digital signal processing system that is built in accordance with certain aspects of the invention.
[0014] [0014]FIG. 4A is a system diagram illustrating an embodiment of asymmetric digital subscriber line (ADSL) adapted filtering circuitry that is built in accordance with certain aspects of the invention.
[0015] [0015]FIG. 4B is a system diagram illustrating an embodiment of plain old telephone service/system (POTS) adapted filtering circuitry that is built in accordance with certain aspects of the invention.
[0016] [0016]FIG. 5A is a system diagram illustrating an embodiment of very high speed asymmetric digital subscriber line (VDSL) adapted filtering circuitry that is built in accordance with certain aspects of the invention.
[0017] [0017]FIG. 5B is a system diagram illustrating an embodiment of plain old telephone system (POTS) and asymmetric digital subscriber line (ADSL) adapted filtering circuitry that is built in accordance with certain aspects of the invention.
[0018] [0018]FIG. 6 is a system diagram illustrating an embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0019] [0019]FIG. 7 is a system diagram illustrating an embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0020] [0020]FIG. 8 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0021] [0021]FIG. 9 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0022] [0022]FIG. 10 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0023] [0023]FIG. 11 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0024] [0024]FIG. 12 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0025] [0025]FIG. 13 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention.
[0026] [0026]FIG. 14A is a functional block diagram illustrating an embodiment matrix switching operation that is performed in accordance with certain aspects of the invention.
[0027] [0027]FIG. 14B is a functional block diagram illustrating an embodiment matrix switching operation that is performed in accordance with certain aspects of the invention.
[0028] [0028]FIG. 14C is a functional block diagram illustrating an embodiment matrix switching operation that is performed in accordance with certain aspects of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] [0029]FIG. 1 is a system diagram illustrating an embodiment of a subscriber network 100 that is built in accordance with certain aspects of the invention. The subscriber network 100 is operable to provide service to any indefinite number of subscribers, shown as a subscriber #1 111 , a subscriber #2 112 , a subscriber #3 113 , . . . , and a subscriber #n 119 . Each of the subscriber #1 111 , the subscriber #2 112 , the subscriber #3 113 , . . . , and the subscriber #n 119 is able to service a point to point twisted pair connection to a central office 120 . A subscriber connection to the central office 120 is made using a conventional telephone line in certain embodiments of the invention. Moreover, and alternatively, each of the subscriber #1 111 , the subscriber #2 112 , the subscriber #3 113 , . . . , and the subscriber #n 119 is able to service a connection to a digital loop carrier (DLC) 130 in even other embodiments.
[0030] The central office 120 includes a main distribution frame (MDF) 122 to which each of the subscriber #1 111 , the subscriber #2 112 , the subscriber #3 113 , . . . , and the subscriber #n 119 first connects within the central office 120 . The central office 120 also includes a plain old telephone system (POTS) splitter 124 to which each of the various subscribers is able to connect via the MDF 122 . In certain embodiments of the invention, the POTS splitter is operable to perform frequency division of the incoming spectrum for various applications. As will be seen in some of the other various applications, the filtering that may be performed in various embodiments of the invention can differ greatly, yet the totality of the invention is operable to accommodate any and all of a variety of filtering needs (including frequency division multiplexing) as required by particular applications. Then, the central office 120 also includes a class 5 switch 128 , known to those having skill in the art, that allows also for point to point connectivity from any one of the subscribers. The class 5 switch 128 is operable to provide connectivity externally from the central office 120 to a network 190 .
[0031] In addition, the POTS splitter 124 provides for point to point connectivity to a multiservice access platform (MSAP) 126 . As may be deduced in various embodiments of the invention, one particular embodiment of an MSAP, without departing from the scope and spirit of the invention, includes a digital subscriber line access multiplexor (DSLAM). However, the terminology MSAP is more appropriate for certain embodiments of the invention given the novel and improved functionality offered therein. The MSAP 126 is also operable to provide connectivity externally from the central office 120 to a network 190 .
[0032] The network 190 is shown as having any of a number of various networks. Any of the subscribers is able to access one or more, or all, of the various networks shown within the network 190 in certain embodiments of the invention. In other embodiments, a subscriber may only wish to access one network. Exemplary networks within the network 190 are shown as a public switch(ed) telephone (PSTN) network 191 , a private Internet protocol (I/P) network 192 , a voice over Internet protocol (VoIP) network 193 , . . . , and the Internet 194 itself. The shown networks 191 , 192 , 193 , . . . , and 194 do not comprise an exclusive list, and a person having skill in the art will recognize that any number of different networks, each being accessible through an embodiment of a central office, is included within the scope and spirit of the invention.
[0033] In alternative embodiments, the MSAP 126 also includes a POTS splitter 124 E. The functionality offered by the POTS splitter 124 E may include exactly the same functionality offered by the POTS splitter 124 . The POTS splitter 124 E may be employed in place of, or in conjunction with, the POTS splitter 124 as well. Moreover, in alternative embodiments, a matrix switch 151 is included within the central office 151 to perform switching between the various subscribers and the various networks and services that they seek to solicit. The functionality of matrix switching may alternatively be performed in other locations within the central office 120 , including within various locations within the MSAP 126 , as will be seen below in various embodiments of the invention.
[0034] [0034]FIG. 2 is a system diagram illustrating an embodiment of a multi-service access platform (MSAP) system 200 that is built in accordance with certain aspects of the invention. The MSAP system 200 includes a binder group 205 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 205 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a multi-service access platform (MSAP) 210 . From certain perspectives, the MSAP 210 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments.
[0035] The MSAP 210 includes circuitry operable to perform over-voltage/surge protection 211 . The functionality offered by the over-voltage/surge protection 211 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of overrated current as well. The over-voltage/surge protection 211 interfaces with a transformer (XFRM) 212 . The XFRM 212 is operable to perform DC rejection of any of the inputs contained within the binder group 205 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the MSAP 210 as well.
[0036] The XFRM 212 interfaces with circuitry operable to provide a hybrid network matching impedance (Z match ) 213 . The hybrid network matching impedance (Z match ) 213 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the MSAP 210 . The hybrid network matching impedance (Z match ) 213 interfaces for both up-stream and downstream throughput. The up-stream flow may be accommodated by a possible receiver (Rx) gain 232 , and the down-stream flow is handled by a line driver/transmitter (Tx) gain 231 . Each of the Rx gain 232 and the line driver/Tx gain 231 is communicatively coupled to filtering circuitry 215 . The filtering circuitry 215 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 216 and a Rx filter 217 . Moreover, the filtering circuitry 215 may also include an optional echo canceller 218 . As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application. In addition, the filtering circuitry 215 provides for matrix switch functionality 292 . The matrix switch functionality 292 is operable to perform switching between the various subscribers and the various networks and services that they seek to solicit.
[0037] The filtering circuitry 215 communicatively couples to digital signal processing circuitry 240 . There are any number of various circuitries that may be included within the digital signal processing circuitry 240 , and a subscriber may access any one, any combination, or all of the various circuitries contained therein. Exemplary digital signal processing circuitries 240 includes a plain old telephone system (POTS) digital signal processing circuitry 241 , an asymmetric digital subscriber line (ADSL) digital signal processing circuitry 242 , a very high speed asymmetric digital subscriber line (VDSL) digital signal processing circuitry 243 , an integrated services digital network (ISDN) digital signal processing circuitry 244 , a telephony (1.544 Mbps [telephony], one of the basic signalling systems 24×64 Kb) and/or terrestrial 1 [data] T1 digital signal processing circuitry 245 , . . . , or any other digital signal processing circuitry 249 . The digital signal processing circuitry 240 then communicatively couples to a back plane interface (I/F) 219 . The back plane interface (I/F) 219 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to enable the MSAP is properly interfaced and communicatively couple to a network. Alternatively, the back plane interface (I/F) 219 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 219 and the network to which it is communicatively coupling.
[0038] The invention allows for any of a number of circuitries within the MSAP 210 to be employed using vacuum microelectronic circuitry as known by those persons having skill in the art. Any one, any combination, or all of the portions 299 may be implemented using vacuum microelectronic circuitry without departing from the scope and spirit of the invention. Particular embodiments are described below, yet those persons having skill in the art will recognize that even those embodiments, of certain combinations and permutations not explicitly shown in the various Figures, may be achieved using vacuum microelectronic circuitry within the scope and spirit of the invention.
[0039] For example, any one, any combination, and/or all of the circuitry operable to perform over-voltage/surge protection 211 , the XFRM 212 , the circuitry operable to provide a hybrid network matching impedance (Z match ) 213 , each of the line driver/Tx gain 231 , the Rx gain 232 , the filtering circuitry 215 including the Tx filter 216 , the Rx filter 217 , and the matrix switching functionality 292 may be implemented using the vacuum microelectronic circuitry in accordance with certain aspects of the invention. Similarly, any one, any combination, and/or all of the circuitry operable to perform over-voltage/surge protection 211 , the XFRM 212 , the circuitry operable to provide a hybrid network matching impedance (Z match ) 213 , each of the line driver/Tx gain 231 , the Rx gain 232 , the filtering circuitry 215 including the Tx filter 216 , the Rx filter 217 , and the matrix switching functionality 292 may also be implemented using solid state technologies. Those having skill in the art will recognize that the scope and spirit of the invention includes the various combinations of devices having portions of vacuum microelectronic circuitry and also solid state circuitries.
[0040] Upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the MSAP system 200 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0041] [0041]FIG. 3 is a system diagram illustrating an embodiment of a digital signal processing system 300 that is built in accordance with certain aspects of the invention. The digital signal processing system 300 includes digital signal processing circuitry 310 . In accordance with the invention, the digital signal processing circuitry 310 may include any number of digital signal processing circuitry including a plain old telephone system (POTS) digital signal processing circuitry 341 , an asymmetric digital subscriber line (ADSL) digital signal processing circuitry 351 , a very high speed asymmetric digital subscriber line (VDSL) digital signal processing circuitry 361 , an integrated services digital network (ISDN) digital signal processing circuitry 371 , a telephony (1.544 Mbps [telephony], one of the basic signaling systems 24×64 Kb) and/or terrestrial 1 [data] T1 digital signal processing circuitry 381 , . . . , or any other digital signal processing circuitry 399 .
[0042] Each of the various digital signal processing circuitries may contain its dedicated digital to analog converter (DAC) and analog to digital converter (ADC) as well as dedicated processing circuitry to perform its requisite functionality. Those persons having skill in the art will recognize that some of the various services and network to be accessed using the digital signal processing circuitry 340 may require different sampling rates, resolution, and other parameters particular to the given service and/or application to be accessed.
[0043] In light of this consideration, the plain old telephone system (POTS) digital signal processing circuitry 341 is shown as having a DAC 342 , an ADC 343 , and a voice processing circuitry 344 . Similarly, the asymmetric digital subscriber line (ADSL) digital signal processing circuitry 351 is shown as having a DAC 352 , an ADC 353 , and an asymmetric digital subscriber line (ADSL) processing circuitry 354 . The very high speed asymmetric digital subscriber line (VDSL) digital signal processing circuitry 361 is shown as having a DAC 362 , an ADC 363 , and a very high speed asymmetric digital subscriber line (VDSL) processing circuitry 344 . The integrated services digital network (ISDN) digital signal processing circuitry 371 is shown as having a DAC 372 , an ADC 373 , and an integrated services digital network (ISDN) processing circuitry 374 . The telephony (1.544 Mbps [telephony], one of the basic signaling systems 24×64 Kb) and/or terrestrial 1 [data] T1 digital signal processing circuitry 381 is shown as having a DAC 382 , an ADC 383 , and a T1 processing circuitry 344 .
[0044] Similarly, the other digital signal processing circuitry 399 may also include a DAC, an ADC, and a dedicated processing circuitry to facilitate the operation and services of the other digital signal processing circuitry 399 as well.
[0045] [0045]FIG. 4A is a system diagram illustrating an embodiment of asymmetric digital subscriber line (ADSL) adapted filtering circuitry 400 A that is built in accordance with certain aspects of the invention. The asymmetric digital subscriber line (ADSL) adapted filtering circuitry 400 A includes filtering circuitry 415 A that performs the functionality of a high pass (HP) filter 416 A for the down-stream or Tx path and that also performs the functionality of a low pass (LP) filter 417 A for the up-stream or Rx path. The operation of the low pass (LP) filter 417 A may also include the operation of splitting off a 4 kHz region for POTS at the DC end of the band when this portion has not been dealt with in preceding circuitry. When the 4 kHz region for POTS at the DC end of the band has already been dealt with, then the use of a simple LPF may be used. Those persons having skill in the art will recognize the functionality and the spectrum division of the filtering performed to accommodate asymmetric digital subscriber line (ADSL) services.
[0046] [0046]FIG. 4B is a system diagram illustrating an embodiment of plain old telephone service/system (POTS) adapted filtering circuitry 400 B that is built in accordance with certain aspects of the invention. The plain old telephone service/system (POTS) adapted filtering circuitry 400 B includes filtering circuitry 415 B that performs the functionality of a low pass (LP) filter 416 B for the down-stream or Tx path and that also performs the functionality of a low pass (LP) filter 417 A for the up-stream or Rx path. In this embodiment of filtering that may be performed in accordance with certain aspects of the invention, the lower ends of the frequency band are the same for both the down-stream or Tx path and the up-stream or Rx path. This region of the frequency spectrum includes the 4 kHz region for POTS at the DC end of the band. Those persons having skill in the art will recognize the functionality and the spectrum division of the filtering performed to accommodate plain old telephone service/system (POTS) services.
[0047] [0047]FIG. 5A is a system diagram illustrating an embodiment of very high speed asymmetric digital subscriber line (VDSL) adapted filtering circuitry 500 A that is built in accordance with certain aspects of the invention. The very high speed asymmetric digital subscriber line (VDSL) adapted filtering circuitry 500 A includes filtering circuitry 515 A that performs the functionality of a band pass (BP) filter 516 A for the down-stream or Tx path and that also performs the functionality of a band pass (BP) filter 517 A for the up-stream or Rx path. In this embodiment of filtering that may be performed in accordance with certain aspects of the invention, the band pass (BP) filter 516 A for the down-stream or Tx path operates using a lower end of the spectrum than the band pass (BP) filter 517 A for the up-stream or Rx path. Those persons having skill in the art will recognize the functionality and the spectrum division of the filtering performed to accommodate very high speed asymmetric digital subscriber line (VDSL) services.
[0048] [0048]FIG. 5B is a system diagram illustrating an embodiment of plain old telephone system (POTS) and asymmetric digital subscriber line (ADSL) adapted filtering circuitry 500 B that is built in accordance with certain aspects of the invention. The plain old telephone system (POTS) and asymmetric digital subscriber line (ADSL) adapted filtering circuitry 500 B includes filtering circuitry 515 B that performs the functionality of a low pass (LP) and high pass (HP) filter 516 B for the down-stream or Tx path and that also performs the functionality of a low pass (LP) and a band pass (BP) filter 517 B for the up-stream or Rx path. In this embodiment of filtering that may be performed in accordance with certain aspects of the invention, the low pass (LP) and high pass (HP) filter 516 B for the down-stream or Tx path operates using a lower end of the spectrum than the band pass (BP) filter portion of the low pass (LP) and a band pass (BP) filter 517 B for the up-stream or Rx path. In addition, the lower ends of the frequency spectrum captured by the low pass (LP) filter portions of the combination filters 516 B and 517 B are geared to the 4 kHz region for POTS at the DC end of the band. Those persons having skill in the art will recognize the functionality and the spectrum division of the filtering performed to accommodate both the plain old telephone system (POTS) and asymmetric digital subscriber line (ADSL) services in a single filtering circuitry.
[0049] Moreover, those persons having skill in the art will recognize the adaptability of the invention to accommodate filtering for any one, any combination, and/or all of the various services and networks proffered within various embodiments of the invention. These FIGS. 4A, 4B, 5 A, and 5 B are exemplary and not exhaustive, and one having skill in the art will understand, in light of the description within this patent application, that filtering may be extended to include such variations and permutations as required by particular applications. Moreover, the adaptability of the filtering may be adapted to accommodate services not yet envisioned, given the relative ease with which the filtering circuitry may be configured and modified, as also implemented using vacuum microelectronic circuitry within the various embodiments.
[0050] [0050]FIG. 6 is a system diagram illustrating an embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system 600 that is built in accordance with certain aspects of the invention. The MSAP system 600 includes a binder group 605 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 605 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a vacuum microelectronic circuitry (VMC) adapted multi-service access platform (VMC MSAP) 610 . From certain perspectives, the VMC MSAP 610 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments.
[0051] The VMC MSAP 610 includes circuitry operable to perform over-voltage/surge protection 611 . The functionality offered by the over-voltage/surge protection 611 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of over-rated current as well. The over-voltage/surge protection 611 interfaces with a transformer (XFRM) 612 . The XFRM 612 is operable to perform DC rejection of any of the inputs contained within the binder group 605 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the VMC MSAP 610 as well.
[0052] The XFRM 612 interfaces with circuitry operable to provide a hybrid network matching impedance (Z match ) 613 . The hybrid network matching impedance (Z match ) 613 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the VMC MSAP 610 . The hybrid network matching impedance (Z match ) 613 interfaces for both up-stream and down-stream throughput using a line driver/matrix switching VMC 690 . The driver/matrix switching VMC 690 performs line driver/transmitter (Tx) gain functionality 691 and receiver (Rx) gain functionality 693 as well as matrix switching functionality 691 . The matrix switch functionality 691 is operable to perform switching between the various subscribers and the various networks and services that they seek to solicit. The line driver/matrix switching VMC 690 is communicatively coupled to filtering circuitry 615 . The filtering circuitry 615 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 616 and a Rx filter 617 . Moreover, the filtering circuitry 615 may also include an optional echo canceller. As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application.
[0053] The filtering circuitry 615 communicatively couples to digital signal processing circuitry 640 . The digital signal processing circuitry 640 then communicatively couples to a back plane interface (I/F) 619 . The back plane interface (I/F) 619 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to ensure that the VMC MSAP 610 is properly interfaced and communicatively coupled to a network. Alternatively, the back plane interface (I/F) 619 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 619 and the network to which it is communicative coupling.
[0054] Similar to the embodiment described above in the FIG. 2, upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the VMC MSAP system 600 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0055] [0055]FIG. 7 is a system diagram illustrating an embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system 700 that is built in accordance with certain aspects of the invention. The MSAP system 700 includes a binder group 705 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 705 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a vacuum microelectronic circuitry (VMC) adapted multi-service access platform (VMC MSAP) 710 . From certain perspectives, the VMC MSAP 710 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments.
[0056] The VMC MSAP 710 includes circuitry operable to perform over-voltage/surge protection 711 . The functionality offered by the over-voltage/surge protection 711 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of over-rated current as well. The over-voltage/surge protection 711 interfaces with a matrix switching vacuum microelectronic circuitry (VMC) 790 . The matrix switching VMC 790 is configured to perform matrix switching functionality 792 for both up and down stream paths. The matrix switching vacuum microelectronic circuitry (VMC) 790 is communicatively coupled to a transformer (XFRM) 712 . The XFRM 712 is operable to perform DC rejection of any of the inputs contained within the binder group 705 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the VMC MSAP 710 as well.
[0057] The XFRM 712 interfaces with circuitry operable to provide a hybrid network matching impedance (Z match ) 713 . The hybrid network matching impedance (Z match ) 713 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the VMC MSAP 710 . The hybrid network matching impedance (Z match ) 713 interfaces for both up-stream and down-stream throughput. The up-stream flow may be accommodated by a possible receiver (Rx) gain 732 , and the down-stream flow is handled by a line driver/transmitter (Tx) gain 731 . Each of the Rx gain 732 and the line driver/Tx gain 731 is communicatively coupled to filtering circuitry 715 . The filtering circuitry 715 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 716 and a Rx filter 717 . Moreover, the filtering circuitry 715 may also include an optional echo canceller. As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application. Each of the receiver (Rx) gain 732 and the line driver/transmitter (Tx) gain 731 communicatively couple to filtering circuitry 715 . The filtering circuitry 715 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 716 and a Rx filter 717 . As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application.
[0058] The filtering circuitry 715 communicatively couples to digital signal processing circuitry 740 . The digital signal processing circuitry 740 then communicatively couples to a back plane interface (I/F) 719 . The back plane interface (I/F) 719 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to ensure that the VMC MSAP 710 is properly interfaced and communicatively coupled to a network. Alternatively, the back plane interface (I/F) 719 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 719 and the network to which it is communicative coupling.
[0059] Similar to the embodiment described above in the FIGS. 2, 6, and 7 , upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the VMC MSAP system 700 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0060] [0060]FIG. 8 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system 800 that is built in accordance with certain aspects of the invention. The MSAP system 800 includes a binder group 805 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 805 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a vacuum microelectronic circuitry (VMC) adapted multi-service access platform (VMC MSAP) 810 . From certain perspectives, the VMC MSAP 810 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments.
[0061] The VMC MSAP 810 includes over-voltage/surge protection adapted vacuum microelectronic circuitry (VMC) 890 . The functionality offered by the over-voltage/surge protection adapted VMC 890 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of over-rated current as well. The over-voltage/surge protection adapted VMC 890 interfaces with a transformer (XFRM) 812 . The XFRM 812 is operable to perform DC rejection of any of the inputs contained within the binder group 805 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the VMC MSAP 810 as well.
[0062] The XFRM 812 interfaces with circuitry operable to provide a hybrid network matching impedance (Z match ) 813 . The hybrid network matching impedance (Z match ) 813 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the VMC MSAP 810 . The hybrid network matching impedance (Z match ) 813 interfaces for both up-stream and down-stream throughput. The up-stream flow may be accommodated by a possible receiver (Rx) gain 832 , and the down-stream flow is handled by a line driver/transmitter (Tx) gain 831 . Each of the Rx gain 832 and the line driver/Tx gain 831 is communicatively coupled to filtering circuitry 815 . The filtering circuitry 815 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 816 and a Rx filter 817 . Moreover, the filtering circuitry 815 may also include an optional echo canceller. As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application. Each of the receiver (Rx) gain 832 and the line driver/transmitter (Tx) gain 831 communicatively couple to filtering circuitry 815 . The filtering circuitry 815 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 816 and a Rx filter 817 . As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application.
[0063] The filtering circuitry 815 communicatively couples to digital signal processing circuitry 840 . The digital signal processing circuitry 840 then communicatively couples to a back plane interface (I/F) 819 . The back plane interface (I/F) 819 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to ensure that the VMC MSAP 810 is properly interfaced and communicatively coupled to a network. Alternatively, the back plane interface (I/F) 819 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 819 and the network to which it is communicative coupling.
[0064] Similar to the embodiment described above in the FIGS. 2, 6, and 7 , upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the VMC MSAP system 800 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0065] [0065]FIG. 9 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system 900 that is built in accordance with certain aspects of the invention. The MSAP system 900 includes a binder group 905 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 905 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a vacuum microelectronic circuitry (VMC) adapted multi-service access platform (VMC MSAP) 910 . From certain perspectives, the VMC MSAP 910 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments.
[0066] The VMC MSAP 910 includes circuitry operable to perform over-voltage/surge protection 911 . The functionality offered by the over-voltage/surge protection 911 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of over-rated current as well. The over-voltage/surge protection 911 interfaces with a transformer adapted vacuum microelectronic circuitry (XFRM VMC) 912 . The XFRM VMC 912 is operable to perform DC rejection of any of the inputs contained within the binder group 905 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the VMC MSAP 910 as well.
[0067] The XFRM VMC 912 interfaces with circuitry operable to provide a hybrid network matching impedance (Z match ) 913 . The hybrid network matching impedance (Z match ) 913 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the VMC MSAP 910 . The hybrid network matching impedance (Z match ) 913 interfaces for both upstream and down-stream throughput. The up-stream flow may be accommodated by a possible receiver (Rx) gain 932 , and the down-stream flow is handled by a line driver/transmitter (Tx) gain 931 . Each of the Rx gain 932 and the line driver/Tx gain 931 is communicatively coupled to filtering circuitry 915 . The filtering circuitry 915 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 916 and a Rx filter 917 . Moreover, the filtering circuitry 915 may also include an optional echo canceller. As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application. Each of the receiver (Rx) gain 932 and the line driver/transmitter (Tx) gain 931 communicatively couple to filtering circuitry 915 . The filtering circuitry 915 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 916 and a Rx filter 917 . As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application.
[0068] The filtering circuitry 915 communicatively couples to digital signal processing circuitry 940 . The digital signal processing circuitry 940 then communicatively couples to a back plane interface (I/F) 919 . The back plane interface (I/F) 919 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to ensure that the VMC MSAP 910 is properly interfaced and communicatively coupled to a network. Alternatively, the back plane interface (I/F) 919 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 919 and the network to which it is communicative coupling.
[0069] Similar to the embodiment described above in the FIGS. 2, 6 7 , and 8 , upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the VMC MSAP system 900 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0070] [0070]FIG. 10 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention. The MSAP system 1000 includes a binder group 1005 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 1005 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a vacuum microelectronic circuitry (VMC) adapted multi-service access platform (VMC MSAP) 1010 . From certain perspectives, the VMC MSAP 1010 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments.
[0071] The VMC MSAP 1010 includes circuitry operable to perform over-voltage/surge protection 1011 . The functionality offered by the over-voltage/surge protection 1011 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of over-rated current as well. The over-voltage/surge protection 1011 interfaces with a transformer (XFRM) 1012 . The XFRM 1012 is operable to perform DC rejection of any of the inputs contained within the binder group 1005 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the VMC MSAP 1010 as well.
[0072] The XFRM 1012 interfaces with hybrid network matching impedance (Z match ) adapted vacuum microelectronic circuitry (VMC) 1013 . The hybrid network matching impedance (Z match ) adapted VMC 1013 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the VMC MSAP 1010 . The hybrid network matching impedance (Z match ) adapted VMC 1013 interfaces for both up-stream and down-stream throughput. The upstream flow may be accommodated by a possible receiver (Rx) gain 1032 , and the down-stream flow is handled by a line driver/transmitter (Tx) gain 1031 . Each of the Rx gain 1032 and the line driver/Tx gain 1031 is communicatively coupled to filtering circuitry 1015 . The filtering circuitry 1015 is operable perform filtering for both the transmit (down-stream) and receive (upstream) paths, as shown by a Tx filter 1016 and a Rx filter 1017 . Moreover, the filtering circuitry 1015 may also include an optional echo canceller. As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application. Each of the receiver (Rx) gain 1032 and the line driver/transmitter (Tx) gain 1031 communicatively couple to filtering circuitry 1015 . The filtering circuitry 1015 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 1016 and a Rx filter 1017 . As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application.
[0073] The filtering circuitry 1015 communicatively couples to digital signal processing circuitry 1040 . The digital signal processing circuitry 1040 then communicatively couples to a back plane interface (I/F) 1019 . The back plane interface (I/F) 1019 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to ensure that the VMC MSAP 1010 is properly interfaced and communicatively coupled to a network. Alternatively, the back plane interface (I/F) 1019 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 1019 and the network to which it is communicative coupling.
[0074] Similar to the embodiment described above in the FIGS. 2, 6, 7 , 8 , and 9 , upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the VMC MSAP system 1000 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0075] [0075]FIG. 11 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention. The MSAP system 1100 includes a binder group 11 05 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 1105 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a vacuum microelectronic circuitry (VMC) adapted multi-service access platform (VMC MSAP) 1110 . From certain perspectives, the VMC MSAP 1110 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments.
[0076] The VMC MSAP 11 10 includes circuitry operable to perform over-voltage/surge protection 1111 . The functionality offered by the over-voltage/surge protection 1111 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of over-rated current as well. The over-voltage/surge protection 1111 interfaces with a transformer (XFRM) 1112 . The XFRM 1112 is operable to perform DC rejection of any of the inputs contained within the binder group 1105 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the VMC MSAP 1110 as well.
[0077] The XFRM 1112 interfaces with a circuitry that is operable to provide a hybrid network matching impedance (Z match ) 1113 . The hybrid network matching impedance (Z match ) 1113 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the VMC MSAP 1110 . The hybrid network matching impedance (Z match ) 1113 interfaces for both up-stream and down-stream throughput. The up-stream flow may be accommodated by a possible receiver (Rx) gain 1132 , and the down-stream flow is handled by a line driver/transmitter (Tx) gain 1131 . Each of the Rx gain 1132 and the line driver/Tx gain 1131 is communicatively coupled to filtering adapted vacuum microelectronic circuitry (VMC) 1115 . The filtering adapted VMC 1115 is configured to provide functionality to perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 1116 and a Rx filter 1117 . Moreover, the filtering adapted VMC 1115 may also be configured to perform the optional functionality of an echo canceller. As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application. Each of the receiver (Rx) gain 1132 and the line driver/transmitter (Tx) gain 1131 communicatively couple to filtering circuitry 1115 . The filtering circuitry 1115 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 1116 and a Rx filter 1117 . As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application.
[0078] The filtering circuitry 11 15 communicatively couples to digital signal processing circuitry 1140 . The digital signal processing circuitry 1140 then communicatively couples to a back plane interface (I/F) 1119 . The back plane interface (I/F) 1119 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to ensure that the VMC MSAP 1110 is properly interfaced and communicatively coupled to a network. Alternatively, the back plane interface (I/F) 1119 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 1119 and the network to which it is communicative coupling.
[0079] Similar to the embodiment described above in the FIGS. 2, 6, 7 , 8 , 9 , and 10 , upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the VMC MSAP system 1100 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0080] [0080]FIG. 12 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention. The MSAP system 1200 includes a binder group 1205 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 1205 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a vacuum microelectronic circuitry (VMC) adapted multi-service access platform (VMC MSAP) 1210 . From certain perspectives, the VMC MSAP 1210 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments. Moreover, an entire portion of the VMC MSAP 1210 is composed of adapted vacuum microelectronic circuitry (VMC) 1290 .
[0081] The VMC MSAP 1210 includes circuitry operable to perform over-voltage/surge protection 1211 . The functionality offered by the over-voltage/surge protection 1211 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of over-rated current as well. The over-voltage/surge protection 1211 interfaces with a transformer adapted vacuum microelectronic circuitry (XFRM VMC) 1212 . The XFRM VMC 1212 is operable to perform DC rejection of any of the inputs contained within the binder group 1205 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the VMC MSAP 1210 as well.
[0082] The XFRM VMC 1212 interfaces with hybrid network matching impedance (Z match ) adapted vacuum microelectronic circuitry (VMC) 1213 . The hybrid network matching impedance (Z match ) adapted VMC 1213 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the VMC MSAP 1210 . The hybrid network matching impedance (Z match ) adapted VMC 1213 interfaces for both up-stream and down-stream throughput. The up-stream flow may be accommodated by a possible receiver (Rx) gain adapted VMC 1232 , and the down-stream flow is handled by a line driver/transmitter (Tx) gain adapted VMC 1231 . Each of the Rx gain adapted VMC 1232 and the line driver/Tx gain adapted VMC 1231 is communicatively coupled to filtering adapted vacuum microelectronic circuitry (VMC) 1215 . The filtering adapted VMC 1215 is configured to provide functionality to perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 1216 and a Rx filter 1217 . Moreover, the filtering adapted VMC 1215 may also be configured to perform the optional functionality of an echo canceller. As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application. Each of the receiver (Rx) gain 1232 and the line driver/transmitter (Tx) gain 1231 communicatively couple to filtering circuitry 1215 . The filtering circuitry 1215 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 1216 and a Rx filter 1217 . As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application.
[0083] The filtering circuitry 1215 communicatively couples to digital signal processing circuitry 1240 . The digital signal processing circuitry 1240 then communicatively couples to a back plane interface (I/F) 1219 . The back plane interface (I/F) 1219 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to ensure that the VMC MSAP 1210 is properly interfaced and communicatively coupled to a network. Alternatively, the back plane interface (I/F) 1219 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 1219 and the network to which it is communicative coupling.
[0084] Similar to the embodiment described above in the FIGS. 2, 6, 7 , 8 , 9 , 10 , and 11 , upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the VMC MSAP system 1200 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0085] [0085]FIG. 13 is a system diagram illustrating another embodiment of a vacuum microelectronic circuitry multi-service access platform (MSAP) system that is built in accordance with certain aspects of the invention. The MSAP system 1300 includes a binder group 1305 that may include a number of subscriber lines. The particular number of subscriber lines included within the binder group 1305 is variable in certain instances, and the scalability of the invention is operable to accommodate any of the various number of subscriber lines. The binder group is shown as interfacing with a vacuum microelectronic circuitry (VMC) adapted multi-service access platform (VMC MSAP) 1310 . From certain perspectives, the VMC MSAP 1310 may be viewed as being located within a central office. Alternatively, it may be viewed as being within a digital loop carrier (DLC) in other embodiments. Moreover, an entire portion of the VMC MSAP 1310 is composed of adapted vacuum microelectronic circuitry (VMC) 1390 .
[0086] The VMC MSAP 1310 includes over-voltage/surge protection adapted vacuum microelectronic circuitry (VMC) 1311 . The over-voltage/surge protection adapted VMC 1311 includes lightning protection, protection from over-rated voltage getting on the system, and protection against surges of over-rated current as well. The over-voltage/surge protection adapted VMC 1311 interfaces with a transformer adapted vacuum microelectronic circuitry (XFRM VMC) 1312 . The XFRM VMC 1312 is operable to perform DC rejection of any of the inputs contained within the binder group 1305 . Alternatively, any requisite DC rejection or other filtering may also be performed in other areas within the VMC MSAP 1310 as well.
[0087] The XFRM VMC 1312 interfaces with hybrid network matching impedance (Z match ) adapted vacuum microelectronic circuitry (VMC) 1313 . The hybrid network matching impedance (Z match ) adapted VMC 1313 is operable to perform impedance matching of the network to ensure maximum power and signal throughput, among other benefits of providing impedance matching between the network and the VMC MSAP 1310 . The hybrid network matching impedance (Z match ) adapted VMC 1313 interfaces for both up-stream and down-stream throughput. The up-stream flow may be accommodated by a possible receiver (Rx) gain adapted VMC 1332 , and the down-stream flow is handled by a line driver/transmitter (Tx) gain adapted VMC 1331 . Each of the Rx gain adapted VMC 1332 and the line driver/Tx gain adapted VMC 1331 is communicatively coupled to filtering adapted vacuum microelectronic circuitry (VMC) 1315 . The filtering adapted VMC 1315 is configured to provide functionality to perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 1316 and a Rx filter 1317 . Moreover, the filtering adapted VMC 1315 may also be configured to perform the optional functionality of an echo canceller. As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application. Each of the receiver (Rx) gain 1332 and the line driver/transmitter (Tx) gain 1331 communicatively couple to filtering circuitry 1315 . The filtering circuitry 1315 is operable perform filtering for both the transmit (down-stream) and receive (up-stream) paths, as shown by a Tx filter 1316 and a Rx filter 1317 . As mentioned above, and as will be described in even more detail below in various embodiments of the invention, the particular filtering that is to be performed for each of the potential services and networks that is to be accessed may various from application to application.
[0088] The filtering circuitry 1315 communicatively couples to digital signal processing circuitry 1340 . The digital signal processing circuitry 1340 then communicatively couples to a back plane interface (I/F) 1319 . The back plane interface (I/F) 1319 is operable to communicatively couple to a network interface card or any other network interface circuitry that is operable to ensure that the VMC MSAP 1310 is properly interfaced and communicatively coupled to a network. Alternatively, the back plane interface (I/F) 1319 itself may be designed to include network interfacing circuitry, thereby obviating the need of an additional network interface card between the back plane interface (I/F) 1319 and the network to which it is communicative coupling.
[0089] Similar to the embodiment described above in the FIGS. 2, 6, 7 , 8 , 9 , 10 , 11 , and 12 , upon reviewing the various embodiments of the invention disclosed within this patent application, those persons having skill in the art will recognize that many of the various functionality devices within the VMC MSAP system 1300 may be transposed without departing from the scope and spirit of the invention. For example, the over-voltage/surge protection may be provided immediately before interfacing with any digital signal processing circuitry in various embodiments of the invention. The variations of moving and re-ordering such transposable devices does not depart from the scope and spirit of the invention.
[0090] [0090]FIG. 14A is a functional block diagram illustrating an embodiment matrix switching operation that 1400 A is performed in accordance with certain aspects of the invention. A matrix switch 1410 A is shown as being operable to perform switching between an indefinite number of inputs 1, 2, . . . , and n to an indefinite number of outputs 1, 2, . . . , and m. The number of outputs m may differ from the number of inputs n. In addition, the number of outputs m may be less than the number of inputs n; the number of outputs m may be also be greater than the number of inputs n (as shown by the dotted line to the optional output m). The matrix switch 1410 A may be employed in any of the various embodiments of the invention shown above. In addition as also shown above in many of the various embodiments, the matrix switch 1410 A may also be employed within the different locations within the various embodiments shown above. The indefinite number of inputs n and outputs m is shown, among other reasons, to display the adaptability of the switching functionality of the matrix switch 1410 A and its ability to be adapted to any number of applications.
[0091] [0091]FIG. 14B is a functional block diagram illustrating an embodiment matrix switching operation 1400 B that is performed in accordance with certain aspects of the invention. From certain perspectives, the matrix switch 1400 B is one of the particular embodiments of the matrix switch 1400 A as shown above in the FIG. 14A. The FIG. 14B shows one embodiment of matrix switching operation that is ideally tailored to application within any of the multi-service access platforms described above in the various embodiments of the invention. For example, as shown above, the matrix switch functionality may be located in any number of the various locations within the various embodiments without departing from the scope and spirit of the invention. However, from at least one perspective, the matrix switch 1400 B is appropriately chosen in terms of input to output to accommodate the needs and requirements of a binder group, containing any number of subscriber lines, in terms of the physical limits within a central office including considerations such as cross-talk, board impedance, trace impedance, and other considerations relating to the performance and layout of a number of subscriber lines coming into a central office having a fixed size and processing capabilities. The scalability of the matrix switching functionality employed within the invention is theoretically indefinite, as described in the FIG. 14A, yet the invention is also adaptable to situations where the physical constraints of a given application present limits such as the number of lines and the number of devices that may be employed within a particular application.
[0092] As shown in the FIG. 14B, a matrix switch 1410 B is shown as being operable to perform switching between a number of inputs 1, 2, . . . , and 300 to a number of outputs 1, 2, . . . , and 50. The number of outputs is 300, and the number of inputs is 50. This 300×50 switching matrix size is appropriately chosen and is operable to meet a particular number of design requirements within the digital subscriber line (DSL) context.
[0093] [0093]FIG. 14C is a functional block diagram illustrating an embodiment matrix switching operation 1400 C that is performed in accordance with certain aspects of the invention. From certain perspectives, the matrix switch 1400 C is one of the particular embodiments of the matrix switch 1400 A as shown above in the FIG. 14A. The FIG. 14C shows one embodiment of matrix switching operation that is operable using one of any number of commercially available vacuum microelectronic circuitry products. Some products are operable to perform 1500×1500 matrix switching. While this total number of operable switching may be viewed as being overkill in certain embodiments of the invention, the availability of such matrix switching may be fully utilized in different embodiments.
[0094] As shown in the FIG. 14B, a matrix switch 1410 B is shown as being operable to perform switching between a number of inputs 1, 2, . . . , and 1500 to an identical number of outputs 1, 2, . . . , and 15000. The number of outputs is 1500, and the number of inputs is 1500. This 1500×1500 switching matrix size is just one such sized and available vacuum microelectronic circuitry product device.
[0095] Moreover, the availability of such high density vacuum microelectronic circuitry allows operation for a number of applications. For example, a re-configured or adapted vacuum microelectronic circuitry could be generated to include various functionality offered by the inherent anode-cathode characteristics offered within the vacuum microelectronic circuitry for any number of applications including over-voltage/surge protection, hybrid network matching impedance (Z match ), line driver functionality, gain and voltage stepping functionality, filtering functionality, and of course matrix switching. The invention has disclosed many embodiments that employ the configurable nature of such vacuum microelectronic circuitry within such applications besides simply matrix switching. If desired, the high density of gas chambers allowed within these vacuum microelectronic circuitry devices are operable to perform one, all, or combinations of these various functions without departing from the scope and spirit of the invention. As desired within a particular application, the total number of functions that are implemented within the vacuum microelectronic circuitry will vary, yet the scope and spirit of the invention includes each of these various permutations. Many of these permutations have been shown explicitly, yet those having skill in the art will recognize the ability of this design to be easily extended to such other embodiments as well.
[0096] In view of the above detailed description of the invention and associated drawings, other modifications and variations will now become apparent to those skilled in the art. It should also be apparent that such other modifications and variations may be effected without departing from the spirit and scope of the invention.
|
Twisted pair termination using vacuum microelectronic circuitry. The invention is operable to increase greatly the number of subscriber lines to access any number of networks. Certain aspects of the invention employ vacuum microelectronic circuitry that offers a dramatic increase in matrix switch density compared with other technologies. The invention includes a reconfigured/modified version of vacuum microelectronic circuitry to perform any number of applications towards which such technology is not currently directed including line driving, voltage stepping, amplification, impedance matching, filtering, and over-voltage/surge protection including lightning protection. The present implementations of vacuum microelectronic circuitry are primarily directed towards performing large amounts of matrix switching, sometimes on the order of servicing 1500×1500 matrices. In certain embodiments of the invention, the matrix size is dramatically reduced to 300×50, as optimally designed to accommodate and service the particular physical constraints including board and interface real estate, system impedances, and multiplexing limitations for various technologies.
| 7
|
[0001] This application claims benefit of U.S. Provisional Application No. 60/460,676, filed Apr. 4, 2003 and Ser. No. 10/817,628, filed Apr. 2, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to laminated glass structures. This invention particularly relates to laminated glass structures that can withstand severe impact and/or severe pressure loads.
[0004] 2. Description of the Prior Art
[0005] Conventional glazing structures comprise a glazing element mounted in or to a support structure such as a frame. Such glazing elements can comprise a laminate window, such as a glass/interlayer/glass laminate window. There are various glazing methods known and which are conventional for constructing windows, doors, or other glazing elements for commercial and/or residential buildings. Such glazing methods are, for example: exterior pressure plate glazing; flush glazing; marine glazing; removable stop glazing; and, silicone structural glazing (also known as stopless glazing).
[0006] For example, U.S. Pat. No. 4,406,105 describes a structurally glazed system whereby holes are created through the glazing element and a plate member system with a connection being formed through the hole.
[0007] Threat-resistant windows and glass structures are known and can be constructed utilizing conventional glazing methods. U.S. Pat. No. 5,960,606 ('606) and U.S. Pat. No. 4,799,376 ('376) each describes laminate windows that are made to withstand severe forces. In International Publication Number WO 98/28515 (IPN '515) a glass laminate is positioned in a rigid channel in which a resilient material adjacent to the glass permits flexing movement between the resilient material and the rigid channel. Other means of holding glazing panels exist such as adhesive tapes, gaskets, putty, and the like and can be used to secure panels to a frame. For example, WO 93/002269 describes the use of a stiffening member that is laminated to a polymeric interlayer around the periphery of a glass laminate to stiffen the interlayer, which can extend beyond the edge of the glass/interlayer laminate. In another embodiment, '269 describes the use of a rigid member, which is inserted into a channel below the surface of a monolithic transparency, and extending from the transparency.
[0008] Windows and glass structures capable of withstanding hurricane-force winds and high force impacts are not trouble-free, however. Conventional glazing methods can require that the glazing element have some extra space in the frame to facilitate insertion or removal of the glazing element. While the additional space facilitates installation, it allows the glazing element to move in a swinging, rocking, or rotational motion within the frame. Further, it can move from side to side (that is, in the transverse direction) in the frame depending upon the magnitude and direction of the force applied against the glazing element. Under conditions of severe repetitive impact and/or either continuous or discontinuous pressure, a glass laminate can move within the frame or structural support in such a way that there can be sufficient stress built up to eventually fracture the window and allow the laminate to be pulled out of the frame. For example, when subjected to severe hurricane force winds the flexing movement in the windows of IPN '515, wherein glass flexes within a rigid channel, can gradually pull the laminate out of the channel resulting in loss of integrity of the structure. In '376, the glass held against the frame can be broken and crushed, causing a loss of structural integrity in the window/frame structure. In WO '269, inserting a stiff foreign body into the interlayer as described therein can set up the structure for failure at the interface where the polymer contacts the foreign body when subjected to severe stresses.
[0009] WO 00/64670 describes glass laminates that utilize the interlayer as a structural element in glazing structures thereby providing greater structural integrity to the laminate during duress or after initial fracture of the glass.
SUMMARY OF THE INVENTION
[0010] In one aspect, the present invention is a glazing element useful for exterior pressure plate glazing comprising a transparent laminate and an attachment means for attaching the laminate to a support structure wherein: (1) the laminate comprises at least one layer of glass bonded directly to a thermoplastic polymer interlayer on at least one surface of the glass; (2) the interlayer extends beyond at least one edge of the laminate; (3) one surface of the extended portion of the interlayer is bonded to at least one surface of the attachment means; (4) another surface of the extended portion of the interlayer is bonded to the glass; (5) the attachment means is a clip useful for aligning and holding the laminate in a retaining channel of the support structure; (6) the clip further comprises at least one interlocking extension useful for restricting rotational and/or transverse movement of the laminate within the channel and/or movement of the laminate out of the channel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a conventional glass laminate in a frame.
[0012] FIG. 2 is a glass/plastic/glass laminate of the present invention comprising a thermoplastic interlayer, wherein the laminate is held in a channel formed from a mullion and a pressure plate, the laminate being held in place with the assistance of an attachment means bonded to the thermoplastic interlayer.
[0013] FIG. 3 depicts a glazing element having a reduced moment arm compared with the glazing element of FIG. 2 due to a redesigned pressure plate.
[0014] FIG. 4 depicts a glazing element comprising an attachment means having two symmetrical extensions and a redesigned mullion having recesses for accepting and constraining one of the extensions.
[0015] FIG. 5 depicts an attachment clip having two symmetrical extensions and a flattened surface.
[0016] FIG. 6 depicts an attachment clip having two extensions that are not identical.
[0017] FIG. 7 depicts an attachment clip having one extension and an adhesive applied inside the channel to restrict rocking of the glazing under negative pressure.
DETAILED DESCRIPTION OF THE INVENTION
[0018] FIG. 1 shows a conventional laminate comprising glass ( 1 ), a thermoplastic interlayer ( 2 ) and glass ( 3 ), the glass being attached to a frame ( 4 ) through an intermediary adhesive layer ( 5 ) which is typically a gasket, putty, sealant tape, or silicone sealant.
[0019] The present invention is a glass laminate system that utilizes the interlayer for the purpose of attaching the laminate to the support structure, as described in WO 00/64670, hereby incorporated by reference. In a process for producing glazing units for architectural applications that incorporate the interlayer as a structural element of the glazing, it has now been found that attaching the interlayer of a glass laminate to a support structure for the laminate can provide glazing units having improved strength and structural integrity against severe threats. The present invention relates to glazing elements that are constructed for exterior pressure plate glazing applications and which utilize the interlayer to attach to the structural support.
[0020] In a conventional exterior pressure plate glazing application, the glazing element is typically inserted into a frame, which comprises a mullion and a pressure plate. The mullion and pressure plate are useful for the purpose of providing an attachment for the glazing element to the building or structure being fitted with the glazing element. The pressure plate is used in concert with the mullion to hold the glazing element securely in place in the frame. The pressure plate is attached to the mullion using a fastener.
[0021] In one embodiment, the glazing element of this invention comprises a support structure capable of supporting a glazing structure comprising a laminate having at least one layer of glass and at least one thermoplastic polymer interlayer that is self-adhered directly to at least one surface of the glass. By self-adhered, it is meant that the interlayer/glass interface does not require and therefore possibly may not include any intervening layers of adhesives and/or glass surface pre-treatment to obtain bonding suitable for use as a safety glass. In some applications it is preferable that there is no intervening film or adhesive layer.
[0022] Thermoplastic polymers useful in the practice of the present invention should have properties that allow the interlayer to provide conventional advantages to the glazing, such as transparency to light, adhesion to glass, and other known and desirable properties of an interlayer material. In this regard, conventional interlayer materials can be suitable for use herein. Conventional interlayer materials include thermoplastic polymers. Suitable polymers include, for example: polyvinylbutyrals (PVB); polyvinyl chlorides (PVC); polyurethanes (PUR); polyvinyl acetate; ethylene acid copolymers and their ionomers; polyesters; copolyesters; polyacetals; and others known in the art of manufacturing glass laminates. Blended materials using any compatible combination of these materials can be suitable, as well. In addition, a suitable interlayer material for use in the practice of the present invention should be able to resist tearing away from a support structure under extreme stress. A sheet of a suitable polymer for use in the practice of the present invention has a high modulus, excellent tear strength and excellent adhesion directly to glass. As such, a suitable interlayer material or material blend should have a Storage Young's Modulus of at least 50 MPa at temperatures up to about 40° C. It can be useful to vary the thickness of the interlayer in order to enhance the tear strength, for example.
[0023] While many conventional thermoplastic polymers can be suitable for use in the practice of the present invention, preferably the polymer is an ethylene acid copolymer. More preferably the thermoplastic polymer is an ethylene acid copolymer obtained by the copolymerization of ethylene and a α,β-unsaturated carboxylic acid, or derivatives thereof. Suitable derivatives of acids useful in the practice of the present invention are known to those skilled in the art, and include esters, salts, anhydrides, amides, nitrites, and the like. Acid copolymers can be fully or partially neutralized to the salt (or partial salt). Fully or partially neutralized acid copolymers are known conventionally as ionomers. Suitable copolymers can include an optional third monomeric constituent that can be an ester of an ethylenically unsaturated carboxylic acid. Suitable acid copolymers useful in the practice of the present invention can be purchased commercially from, for example, E.I. DuPont de Nemours & Company under the trade names of Surlyn® and Nucrel®, for example.
[0024] In the practice of the present invention the edges of the interlayer can be attached either directly to a support structure or indirectly to the support structure by way of an attachment means. As contemplated in the practice of the present invention, a support structure can be any structural element or any combination of structural elements that hold the glazing element in place on the building or support the weight of the glazing element. The support structure can comprise a frame, bolt, screw, wire, cable, nail, staple, and/or any conventional means for holding or supporting a glazing element, or any combination thereof. In the present invention, “support structure” can mean the complete or total support structure, or it can refer to a particular structural component or element of the complete support structure. One skilled in the art of glazing manufacture will know from the context which specific meaning to apply. Direct attachment of the interlayer, as contemplated herein, means a direct attachment of the laminate to the support structure or any element thereof wherein the interlayer is in direct and consistent contact with the support structure. Direct attachment of the interlayer to the support can be from the top, sides, bottom, or through the interlayer material. By indirect attachment it is meant any mode of attachment wherein the interlayer does not have direct contact with the support structure, but does have contact with the support structure through at least one intervening structural component of the glazing element. Indirect attachment of the interlayer to the support structure by way of an attachment means is most preferable in the practice of the present invention. The attachment means can be any means for holding or constraining the glass laminate into a frame or other support structure.
[0025] In a preferred embodiment, the attachment means is an attachment clip that can be bonded to an extended portion of the interlayer by a bonding process. In the practice of the present invention there is no direct contact intended between the clip and any portion of the glass layer(s) of the laminate, and any such contact is incidental. In any event, it can be preferred to minimize contact between the clip and the glass in order to reduce glass fracture under stress or during movement of the laminate in the support structure. To that end, the portion of the interlayer that extends from the edges of the laminate preferably forms an intervening layer between the clip and the glass layer such that the clip does not contact the glass. The surface of the clip that contacts the interlayer can be smooth, but preferably the surface of the clip has at least one projection and/or one recessed area, and more preferably several projections and/or recessed areas, which can provide additional surface area for bonding as well as a mechanical interlocking mechanism with the interlayer to enhance the effectiveness of the adhesive bonding between the clip and the interlayer, thereby providing a laminate/clip assembly with greater structural integrity.
[0026] In another embodiment, a conventional glass laminate unit can be used to create a laminate glazing unit of the present invention. To achieve the same or similar effect as in other embodiments, the interlayer material can be bonded to the thermoplastic material without the necessity of actually extending the interlayer beyond the edges of the laminate. In this embodiment, strips of thermoplastic polymer material suitable for bonding to the thermoplastic interlayer can be positioned on the periphery of the laminate and heated to promote melting, or flow, of the interlayer and the thermoplastic polymer on the periphery of the laminate such that the two materials come into direct contact and become blended. Upon cooling below the melting point of the polymers, the two materials will be bonded to one another and thus be available to perform the bonding function between the glass and the attachment means. Other processes for bonding the interlayer to the attachment means can be contemplated and within the scope of the present invention if the interlayer is effectively extended outside the edges of the laminate by that process. The thermoplastic polymer can be the same polymer as used for the interlayer, or it can be a different material that forms a strong enough bond with the interlayer material under the process conditions used. In a preferred embodiment bonding the thermoplastic strips to the glass of the laminate and to the attachment means can be performed simultaneously.
[0027] A bonding process suitable for use in the practice of the present invention is any wherein the interlayer can be bonded to the attachment means. In the present invention, by “bonding” it is meant that the interlayer and the attachment means form a bond that results in adhesion between the attachment means and the interlayer. Bonding can be accomplished by physical means or by chemical means, or by a combination of both. Physical bonding, for the purposes of the present invention, is adhesion that results from interaction of the interlayer with the attachment means wherein the chemical nature of the interlayer and/or the attachment means is unchanged at the surfaces where the adhesion exists. For example, adhesion that results from intermolecular forces, wherein covalent chemical bonds are neither created nor destroyed, is an example of physical bonding. Chemical bonding, according to the present invention, would require forming and/or breaking covalent chemical bonds at the interface between the interlayer and the attachment means in order to produce adhesion.
[0028] The bonding process of the present invention preferably comprises the step of applying heat to the clip while it is in direct contact with the interlayer, that is, applying heat or energy to a clip/interlayer assembly such that the polymeric interlayer and the clip are bonded at the interface where the clip and interlayer are in contact. Without being held to theory, it is believed that this results in a physical bonding rather than a chemical bonding. Application of heat in the bonding process can be accomplished by various methods, including the use of: a heated tool; microwave energy; or ultrasound to heat the interlayer and/or the attachment clip and promote bonding. Preferably the clip/interlayer assembly can be bonded at a temperature of less than about 175° C., more preferably at a temperature of less than about 165° C. Most preferably, the clip/interlayer assembly can be bonded at a temperature of from about 125° C. to about 150° C. Once bonded, the clip/interlayer/laminate form a laminate/clip assembly that can be fitted or otherwise attached to a frame or other support structure.
[0029] A clip that is suitable for use in the practice of the present invention has a mechanical interlocking extension that can, by interlocking with the support structure, reduce the motion available to the laminate in the channel of a frame, or against any other rigid support structure member. The extension member of the clip can thereby reduce the force of the rigid support structure against the laminate and also assist in holding the laminate in or to the support structure. The extension member can have various forms and/or shapes to accomplish its function. For example, the extension member can form part of a ball and socket; it can form a “C”, an “L”, or a “T” shape to hold it into the support structure, or it can be any sort of extension arm such as a hook or a clamp, for example. Any design of the extension member, which accomplishes the function of facilitating the laminate being held into the support structure, is contemplated as within the scope of the present invention.
[0030] For the purposes of this invention, a laminate/clip assembly of the present invention is said to be attached to a support structure if the assembly is nailed, screwed, bolted, glued, slotted, tied or otherwise constrained from becoming detached from the structure. Preferably, a laminate/clip assembly of the present invention is geometrically and/or physically constrained within a channel formed by elements of a conventional framing structure. In the practice of the present invention, a conventional framing structure comprises a mullion which functions to attach and hold a glazing element to a building, for example. A framing structure useful in the practice of the present invention can comprise a pressure plate and a fastener which functions to hold a glazing element in place against the mullion. Use of pressure plates and mullions in the glazing art for exterior glazing is conventional.
[0031] In one of the preferred embodiments of the present invention, depicted in FIG. 2 , a glazing element ( 1 ) comprises: a glass ( 2 ) /interlayer ( 3 ) /glass ( 2 ) laminate; and an attachment clip ( 4 ). The glazing element is contacted by gaskets ( 7 ), which assist in holding the glazing element in a channel formed by a mullion ( 5 ) and a pressure plate ( 6 ). The attachment clip comprises an interlocking extension ( 9 ), which projects outward and away from the outer edge of the laminate. The arm can function to restrict the movement of the glazing element within the frame channel ( 10 ) by cutting down on the rocking motion available to the laminate upon being subjected to positive pressure at the surfaces of the laminate. In addition, the arm can assist in keeping the laminate from being pulled out by movement of the glazing element from side to side. The fastener ( 11 ) holds the pressure plate and mullion together, and can be tightened or loosened to apply more or less pressure to the gaskets holding the glazing element. A thermal separator ( 12 ) can be used for temperature insulation. The design depicted in FIG. 2 results in a laminate that can withstand either severe positive pressure or negative pressure loads. The clip can optionally comprise an engagement hook at the end of the extension, to assist in retaining the laminate in the frame channel.
[0032] In another embodiment depicted in FIG. 3 , the glazing element shown therein is identical to the glazing element of FIG. 2 . The mullion and pressure plate are identical to FIG. 2 except that the shape of the thermal separator ( 12 ) has been redesigned and inverted in order to reduce the moment arm of the glazing element. The reduced moment arm can further restrict the movement in the channel in a manner that can prevent sufficient force being generated to damage the laminate and/or allow the laminate to be pulled from the structure.
[0033] In another embodiment depicted in FIG. 4 , the glazing element is identical to the glazing element of FIG. 3 , except that the attachment clip ( 4 a ) comprises a second extension arm ( 13 ), which functions to further promote retention of the glazing element in the channel ( 10 ) whether subject to either positive or negative pressure. The mullion of FIG. 4 has a recess ( 14 ) to accept the additional extension arm.
[0034] In another preferred embodiment depicted in FIG. 5 , the glazing element is identical to the glazing element of FIG. 3 , except that the attachment clip ( 4 b ) has a flattened surface, which is more amenable to the application of heat during the clip/interlayer bonding process. The modified design of the clip in FIG. 5 can result in greater glass capture or glass bite, of the laminate in the frame, which can result in greater structural integrity for the glazing element. The mullion of FIG. 5 is identical to the mullion of FIG. 4 .
[0035] In still another preferred embodiment shown in FIG. 6 , the glazing element is identical to the glazing element of FIG. 3 , except that the attachment clip ( 4 c ) comprises a second extension arm ( 13 a ) that is shorter than extension arm ( 9 ), and functions to promote retention of the glazing element in the channel ( 10 ) whether subject to either positive or negative pressure. The mullion of FIG. 6 is identical to the mullion of FIG. 3 .
[0036] In still another preferred embodiment shown in FIG. 7 , the glazing element is identical to the glazing element of FIG. 3 , except that the attachment clip ( 4 ) is bonded to the mullion by an adhesive ( 14 ). While an adhesive is optional in the practice of the present invention, use of an adhesive in this manner does not require great skill and technical prowess to apply the adhesive because the adhesive is not visible outside of the frame of the glazing element.
[0037] A laminate of the present invention has excellent durability, impact resistance, toughness, and resistance by the interlayer to cuts inflicted by glass once the glass is shattered. A laminate of the present invention is particularly useful in architectural applications in buildings subjected to hurricanes and windstorms. A laminate of the present invention that is attached or mounted in a frame by way of the interlayer is not torn from the frame after such stress or attack. A laminate of the present invention also has a low haze and excellent transparency. These properties make glazing elements of the present invention useful as architectural glass, including use for reduction of solar rays, sound control, safety, and security, for example.
[0038] In a preferred embodiment, the interlayer is positioned between the glass plates such that the interlayer is exposed in such a manner that it can be attached to the surrounding frame. The interlayer can be attached to the support structure in a continuous manner along the perimeter of the laminate. Alternatively, the interlayer can be attached to the structural support in a discontinuous manner at various points around the perimeter of the laminate. Any manner of attaching the laminate to the frame by way of the interlayer is considered to be within the scope of the present invention. For example, the frame surrounding the laminate can contain interlayer material that can bond with the laminate and also with the frame; the laminate can be mechanically anchored to the frame with a screw, hook, nail, or clamp, for example. Mechanical attachment includes any physical constraint of the laminate by slotting, fitting, or molding a support to hold the interlayer in place within the structural support.
[0039] Air can be removed from between the layers of the laminate, and the interlayer can be bonded, or adhered, to the glass plates by conventional means, including applying heat and pressure to the structure. In a preferred embodiment, the interlayer can be bonded without applying increased pressure to the structure.
[0040] One preferred laminate of this invention is a transparent laminate comprising two layers of glass and an intermediate thermoplastic polymer interlayer self-adhered to at least one of the glass surfaces. The interlayer preferably has a Storage Young's Modulus of 50-1,000 MPa (mega Pascals) at 0.3 Hz and 25° C., and preferably from about 100 to about 500 MPa, as determined according to ASTM D 5026-95a. The interlayer should remain in the 50-1,000 MPa range of its Storage Young's Modulus at temperatures up to 40° C.
[0041] The laminate can be prepared according to conventional processes known in the art. For example, in a typical process, the interlayer is placed between two pieces of annealed float glass of dimension 12″×12″ (305 mm×305 mm) and 2.5 mm nominal thickness, which have been washed and rinsed in demineralized water. The glass/interlayer/glass assembly is then heated in an oven set at 90-100° C. for 30 minutes. Thereafter, it is passed through a set of nip rolls (roll pressing) so that most of the air in the void spaces between the glass and the interlayer may be squeezed out, and the edge of the assembly sealed. The assembly at this stage is called a pre-press. The pre-press is then placed in an air autoclave where the temperature is raised to 135° C. and the pressure raised to 200 psig (14.3 bar). These conditions are maintained for 20 minutes, after which, the air is cooled while no more air is added to the autoclave. After 20 minutes of cooling when the air temperature in the autoclave is less than 50° C., the excess air pressure is vented. Obvious variants of this process will be known to those of ordinary skill in the art of glass lamination, and these obvious variants are contemplated as suitable for use in the practice of the present invention.
[0042] Preferably, the interlayer of the laminate is a sheet of an ionomer resin, wherein the ionomer resin is a water insoluble salt of a polymer of ethylene and methacrylic acid or acrylic acid, containing about 14-24% by weight of the acid and about 76-86% by weight of ethylene. The ionomer further characterized by having about 10-80% of the acid neutralized with a metallic ion, preferably a sodium ion, and the ionomer has a melt index of about 0.5-50. Melt index is determined at 190° C. according to ASTM D1238. The preparation of ionomer resins is disclosed in U.S. Pat. No. 3,404,134. Known methods can be used to obtain an ionomer resin with suitable optical properties. However, current commercially available acid copolymers do not have an acid content of greater than about 20%. If the behavior of currently available acid copolymer and ionomer resins can predict the behavior of resins having higher acid content, then high acid resins should be suitable for use herein.
[0043] Haze and transparency of laminates of this invention are measured according to ASTM D-1003-61 using a Hazeguard XL211 hazemeter or Hazeguard Plus Hazemeter (BYK Gardner-USA). Percent haze is the diffusive light transmission as a percent of the total light transmission. To be considered suitable for architectural and transportation uses. The interlayer of the laminates generally is required to have a transparency of at least 90% and a haze of less than 5%.
[0044] In the practice of the present invention, use of a primer or adhesive layer can be optional. Elimination of the use of a primer can remove a process step and reduce the cost of the process, which can be preferred.
[0045] Standard techniques can be used to form the resin interlayer sheet. For example, compression molding, injection molding, extrusion and/or calendaring can be used. Preferably, conventional extrusion techniques are used. In a typical process, an ionomer resin suitable for use in the present invention can include recycled ionomer resin as well as virgin ionomer resin. Additives such a colorants, antioxidants and UV stabilizers can be charged into a conventional extruder and melt blended and passed through a cartridge type melt filter for contamination removal. The melt can be extruded through a die and pulled through calendar rolls to form sheet about 0.38-4.6 mm thick. Typical colorants that can be used in the ionomer resin sheet are, for example, a bluing agent to reduce yellowing or a whitening agent or a colorant can be added to color the glass or to control solar light.
[0046] The polymer sheet after extrusion can have a smooth surface but preferably has a roughened surface to effectively allow most of the air to be removed from between the surfaces in the laminate during the lamination process. This can be accomplished for example, by mechanically embossing the sheet after extrusion or by melt fracture during extrusion of the sheet and the like. Air can be removed from between the layers of the laminate by any conventional method such as nip roll pressing, vacuum bagging, or autoclaving the pre-laminate structure.
[0047] The Figures do not represent all variations thought to be within the scope of the present invention. One of ordinary skill in the art of glazing manufacture would know how to incorporate the teachings of the present invention into the conventional art without departing from the scope of the inventions described herein. Any variation of glass/interlayer/glass laminate assembly wherein a frame can be attached to the interlayer—either directly or indirectly through an intermediary layer, for example an adhesive layer, is believed to be within the scope of the present invention.
[0048] For architectural uses a laminate can have two layers of glass and an interlayer of a thermoplastic polymer. Multilayer interlayers are conventional and, can be suitable for use herein, provided that at least one of the layers can be attached to the support structure as described herein. A laminate of the present invention can have an overall thickness of about 3-30 mm. The interlayer can have a thickness of about 0.38-4.6 mm and each glass layer can be at least 1 mm thick. In a preferred embodiment, the interlayer is self-adhered directly to the glass, that is, an intermediate adhesive layer or coating between the glass and the interlayer is not used. Other laminate constructions can be used such as, for example, multiple layers of glass and thermoplastic interlayers; or a single layer of glass with a thermoplastic polymer interlayer, having adhered to the interlayer a layer of a durable transparent plastic film. Any of the above laminates can be coated with conventional abrasion resistant coatings that are known in the art.
[0049] The frame and/or the attachment means can be fabricated from a variety of materials such as, for example: wood; aluminum; steel; and various strong plastic materials including polyvinyl chloride and nylon. Depending on the material used and the type of installation, the frame may or may not be required to overlay the laminate in order to obtain a fairly rigid adhesive bond between the frame and the laminate interlayer.
[0050] The frame can be selected from the many available frame designs in the glazing art. The laminate can be attached, or secured, to the frame with or without use of an adhesive material. It has been found that an interlayer made from ionomer resin self-adheres securely to most frame materials, such as wood, steel, aluminum and plastics. In some applications it may be desirable to use additional fasteners such as screws, bolts, and clamps along the edge of the frame. Any means of anchoring the attachment means to the frame is suitable for use in the present invention.
[0051] In preparing the glazing elements of this invention, autoclaving can be optional. Steps well known in the art such as: roll pressing; vacuum ring or bag pre-pressing; or vacuum ring or bagging; can be used to prepare the laminates of the present invention. In any case, the component layers are brought into intimate contact and processed into a final laminate, which is free of bubbles and has good optics and adequate properties to insure laminate performance over the service life of the application. In these processes the objective is to squeeze out or force out a large portion of the air from between the glass and plastic layer(s). In one embodiment the frame can serve as a vacuum ring. The application of external pressure, in addition to driving out air, brings the glass and plastic layers into direct contact and adhesion develops.
[0052] For architectural uses in coastal areas, the laminate of glass/interlayer/glass must pass a simulated hurricane impact and cycling test which measures resistance of a laminate to debris impact and wind pressure cycling. A currently acceptable test is performed in accordance to the South Florida Building Code Chapter 23, section 2315 Impact tests for wind born debris. Fatigue load testing is determined according to Table 23-F of section 2314.5, dated 1994. This test simulates the forces of the wind plus air born debris impacts during severe weather, e.g., a hurricane. A sample 35 inches×50 inches (88.9×127 cm) of the laminate is tested. The test consists of two impacts on the laminate (one in the center of the laminate sample followed by a second impact in a corner of the laminate). The impacts are done by launching a 9-pound (4.1 kilograms) board nominally 2 inches (5 cm) by 4 inches (10 cm) and 8 feet (2.43 meters) long at 50 feet/second (15.2 meters/second) from an air pressure cannon. If the laminate survives the above impact sequence, it is subjected to an air pressure cycling test. In this test, the laminate is securely fastened to a chamber. In the positive pressure test, the laminate with the impact side outward is fastened to the chamber and a vacuum is applied to the chamber and then varied to correspond with the cycling sequences set forth in Table 1. The pressure cycling schedule, shown in Table 1, is specified as a fraction of the maximum pressure (P). In this test P equals 70 PSF (pounds per square foot), or 3360 Pascals. Each cycle of the first 3500 cycles and subsequent cycles is completed in about 1-3 seconds. On completion of the positive pressure test sequence, the laminate is reversed with the impact side facing inward to the chamber for the negative pressure portion of the test and a vacuum is applied corresponding to the following cycling sequence. The values are expressed as negative values (−).
[0000]
TABLE 1
Number of
Pressure Range [pounds
Air Pressure
Pressure
per
Cycles
Schedule*
square foot (Pascals)]
Positive Pressure (inward acting)
3,500
0.2 P to 0.5 P
14 to 35
(672-1680 Pascals)
300
0.0 P to 0.6 P
0 to 42
(0-2016 Pascals)
600
0.5 P to 0.8 P
35 to 56
(1680-2688 Pascals)
100
0.3 P to 1.0 P
21 to 70
(1008-3360 Pascals)
Negative Pressure (outward acting)
50
−0.3 P to −1.0 P
−21 to −70
(−1008 to −3360 Pascals)
1,060
−0.5 P to −0.8 P
−35 to −56
(−1680 to −2688 Pascals)
50
0.0 P to −0.6 P
−0 to −42
(0 to −2016 Pascals)
3,350
−0.2 P to −0.5 P
−14 to −35
(−672 to −1680 Pascals)
*Absolute pressure level where P is 70 pounds per square foot (3360 Pascals).
[0053] A laminate passes the impact and cycling test when there are no tears or openings over 5 inches (12.7 cm) in length and not greater than 1/16 inch (0.16 cm) in width.
[0054] Other applications may require additional testing to determine whether the glazing is suitable for that particular application. A glazing membrane and corresponding support structure can fail by one of three failure modes:
1.The glazing membrane breaches (a tear or hole develops) as a result of a force being applied to the glazing or surrounding structure. 2. The glazing membrane pulls away or from the support structure losing mechanical integrity such that the glazing membrane no longer provides the intended function, generally a barrier. 3. The support structure fails by loss of integrity within its makeup or loss of integrity between the support structure and the surrounding structure occurs.
Only failure modes 1 and/or 2 defined above are the subject of the present invention.
[0058] The best-optimized system is defined herein as one where no failure occurs in any component/subcomponent of the glazing system when the maximum expected ‘threat’ is applied to the glazing system. When some threshold is exceeded, the ideal failure mode is one where a balance is achieved between failure modes 1 and 2 above. If the glazing membrane itself can withstand substantially more applied force or energy then the support structure has capability to retain the glazing, then the glazing ‘infill’ is over-designed or the glazing support structure is under-designed. The converse is also true.
EXAMPLES
[0059] The Examples are for illustrative purposes only, and are not intended to limit the scope of the invention.
Examples 1 through 3 and Comparative Examples C1 through C3
[0060] Conventional glass laminates were prepared by the following method. Two sheets of annealed glass having the dimensions of 300 mm×300 mm (12 inches square) were washed with de-ionized water and dried. A sheet (2.3 mm thick) of ionomer resin composed of 81% ethylene, 19% methacrylic acid, with 37% of the acid neutralized and having sodium ion as the counter-ion, and having a melt index of 2 was placed between two pieces of glass. A nylon vacuum bag was placed around the prelaminate assembly to allow substantial removal of air from within (air pressure inside the bag was reduced to below 100 millibar absolute). The bagged prelaminate was heated in a convection air oven to 120° C. and held for 30 minutes. A cooling fan was used to cool the laminate to ambient temperature and the laminate was disconnected from the vacuum source and the bag removed yielding a fully bonded laminate of glass and interlayer.
[0061] Laminates of the present invention were prepared in the same manner as above with the following exception. In some of the examples a triangular-shaped ‘corner-box’ retaining assembly as depicted in FIGS. 6 and 9 of the present application, having a wall thickness of 0.2 mm and dimensions of 50 mm×50 mm×71 mm (inside opening of 10 mm) was placed on each corner of the laminate after fitting pieces of ionomer sheet (2.3 mm thickness) within the inside of the box thereby ‘lining’ the inside. The assembly was placed into the vacuum bag and the process above was carried out to directly ‘bond’ the attachment to the interlayer. To better insure that the laminates were free of void areas, that is entrained bubbles, areas of non-contact between the ionomer and glass surface and that good flow and contact was made between the ionomer and the inside of the ‘corner-box’ all laminates were then placed in an air autoclave for further processing. The pressure and temperature inside the autoclave was increased from ambient to 135° C. and 200 psi in a period of 15 minutes. This temperature and pressure was held for 30 minutes and then the temperature was decreased to 40° C. within a 20-minute period whereby the pressure was lowered to ambient atmospheric pressure and the unit was removed.
[0062] A test apparatus similar to that described in SAE Recommended Practice J-2568 (attached as Appendix) was assembled to measure the degree of membrane integrity. The apparatus consisted of a hydraulic cylinder with integral load cell driving a hemispherical metal ram (200 mm diameter) into the center of each glazing sample in a perpendicular manner, measuring the force/deflection characteristics. Deflection was measured with a string-potentiometer attached to the ram. The glazing sample was supported either by a metal frame capturing the sample around the periphery, only at the corners or any configuration where performance information is desired. The data acquisition was done via an interface to a computer system with the appropriate calibration factors. Further treatment of the data was then possible to calculate the Maximum Applied Force (F max ) in Newtons (N), and the deflection. Integration of the data enabled the derivation the total energy expended in reaching a failure point of the glazing or supporting conditions. Testing of the laminates was done after fracturing the laminate in order to more accurately measure the load-bearing capability of the interlayer attachment system.
[0063] Example C1 was an annealed glass plate (10 mm) that was stressed until fracture. The test glazing had a standard installation with all four sides captured by the frame using a typical amount of edge capture (that is, overlap of the frame and glass), and lined with an elastomeric gasket.
[0064] Example C2 was a 90-mil polyvinylbutyral (PVB) laminate that was prefractured. The laminate construction was a typical patch plate design.
[0065] Example C3 was a 90-mil SentryGlas® Plus (SGP) laminate that was prefractured and constructed with a typical patch plate design.
[0066] Example 1 was a laminate of the present invention, using a 90-mil SentryGlas® Plus interlayer that was prefractured and constructed with a full perimeter attachment design (that is, the interlayer was attached to the frame around the full perimeter of the laminate).
[0067] Example 2 was the same as Example 1, except that it was constructed with a corner attachment design.
[0068] Example 3 was the same as Example 2, except that a 180-mil SentryGlas® Plus laminate that was used.
[0069] To measure the relative performance of a glazing membrane capacity against an applied force/energy and the capability for the glazing support structure (or means) to retain the glazing the following testing was performed. The displacement (D), which is defined as the distance traveled by the ram from engaging the laminate to the point of laminate failure, was measured. The membrane strength to integrity (S/R) ratio was measured. The S/R ratio is defined as the ratio of the applied energy required to cause a failure in a given laminate over the applied energy required to break C1. The performance benefit (B) over the traditional patch plate design was calculated by dividing the applied energy required for failure in the laminate by the applied energy required to for failure in C3. The resulting data is supplied in Table 2.
[0000]
TABLE 2
F max
Ex
D (mm)
(N)
S/R
B
C1
9
5284
1
.02
C2
122
108
22
.5
C3
65
939
45
1
1
80
11595
408
9.1
2
80
7243
274
6.1
3
90
9003
452
10.0
Examples 4 through 10 and Comparative Example C4
[0070] Laminates were prepared using 9/16″ thick laminated glass incorporating 0.090″ thick SentryGlas® Plus, available from E.I DuPont de Nemours and Company (DuPont) and ¼″ heat strengthened glass. In all but one respect this is a common glazing alternative used in commercial glazing applications for large missile impact resistance. The improvement over the existing industry standards is the attachment means used, that is, bonding of aluminum profiles to the laminated glass' interlayer edge with a contact-heating device. The aluminum profile was a “u” channel shape with a leg extending from the base of the “u” engaging an interlocking profile design in a custom extruded pressure plate. The 12″ long aluminum profiles were positioned around the glass edge in strategic locations to determine the most optimal location for load transfer within the glazed system. The attachment means geometry used for design validation was purposely designed to minimally impact the framing system into which it was installed. Because of this, the structural performance on inward acting air pressure cyclical loads behaved differently within the system than outward acting air pressure loads. This allowed for validation that the design of the attachment means of the present invention did indeed provide a substantial improvement over conventionally dry glazed systems.
[0071] Eight different individual test specimens were subjected to the test procedures required for large missile impact resistance with the location of the attachment means of the present invention varying with each test specimen. Example C4 was tested without any attachments of the present invention to define a baseline performance standard for a dry-glazed application with ½″ glass bite. Each test specimen was 63″ wide×120″ high and was mounted in a steel test frame to simulate a punched opening installation in a building.
[0072] All of the tested specimens passed the required impact resistance with a 2″×4″ wooden missile weighing 9# and traveling at 50 feet/second. The results of the cycling test for the various test specimens are shown in Table 3. Pressure cycling was conducted according to the Pressure Schedule shown in Table 1. A laminate of the present invention is given a passing mark for (+) load if the laminate holds in the support structure at 4500 cycles in the positive load direction and a passing mark in the (−) load direction at 4500 cycles in the negative load direction. The test laminates (with the exception of the comparative example) were designed so that the attachment means of the present invention was only engaged in the (+) load direction, and retention under negative load would be nearly identical to conventional laminates.
[0073] The units that failed in the negative load direction demonstrated precisely how much of an improvement the attachment means provided the installation. Given that without the attachment means, the limitation for a framing of this type, dry-glazed, with ½″ glass bite is about a 50 PSF design pressure differential. Through testing at least a doubling of the effective design pressure differential to 100 PSF was demonstrated. It is contemplated that higher-pressure loads would have been obtainable had the interior extruded aluminum profiles been designed to accept the attachment clips as well.
[0000]
TABLE 3
Ex
Pressure
Results
Cycles (no.)
C4
+/−50 PSF
Passed +/− loads
9000
4
+/−100 PSF
Failed + load
4424
5
+/−100 PSF
Failed + load
3800
6
+/−100 PSF
Failed + load
4416
7
+/−100 PSF
Passed + load
4509
8
+/−100 PSF
Passed + load
4502
9
+/−100 PSF
Failed + load
4409
10
+/−100 PSF
Passed + load
4500
Examples 11 through 15, C5 and C6
[0074] Laminates of the present invention were constructed similarly to FIGS. 2 and 3 (Examples 1-13) and FIGS. 4 and 5 (Examples 14 and 15). The tensile force required to failure was measured on unbroken laminates and on intentionally broken laminates. Examples 13 and 14 utilized aluminum (Al) frames which were modified with grooves to allow the polymer to flow into channels in the surface of the frames, creating additional mechanical interlocking of polymer to frame. The results are shown in Table 4.
[0000]
TABLE 4
Pre-test
Tensile
Example
Frame Style
Damage
Force (lbs)
C5
gasket
unbroken
24.7
C6
silicone
unbroken
40.7
11
Aluminum
unbroken
265.9
12
Aluminum
broken
166.7
13
Al (grooved)
broken
77.4
14
Al (grooved)
unbroken
440.1
15
Aluminum
broken
210.4
|
This invention is an architectural glazing structure for exterior mounting that is a glass laminate having enhanced resistance to being pulled from a frame upon being subjected to severe positive and/or negative pressure loads. This invention is particularly suitable for architectural structures having windows that can be subjected to the extreme conditions prevalent in a hurricane, or window that can be placed under severe stress from repeated forceful blows to the laminate.
| 8
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method for manufacturing a solar cell, as well as to a solar cell manufactured according to this method.
[0003] 2. Description of the Related Art
[0004] Silicon solar cells are often provided with a metallic coating over an entire surface for reflection and for charge collection on the back side. This backside metallic coating is made of, as a rule, aluminum-based, thick-film paste, which is printed between silver-based soldering surfaces, over a large surface. When sintered above 800° C., the aluminum partially alloys with the upper semiconductor surface by forming the low-melting point (577° C.) AlSi eutectic and recrystallizing, and in the process, it over-compensates for the existing n + -doping from the phosphorus diffusion that had previously occurred all-around, to form highly p-doped (p + -)doping (see F. Huster, 20th European Photovoltaic Solar Energy Conference, Jun. 6-10, 2005, Barcelona, Spain). When the base doping is p, the aluminum-doped, recrystallized surface layer forms a p + -BSF (back surface field) having a p + p-transition (high-low transition).
[0005] For several years, the same cell structure has also been produced on n-doped silicon, using a virtually identical process. Then, the above-mentioned, aluminum-doped surface of the back side becomes the p + -emitter, and the phosphorus-doped layer of the front side becomes the front surface field (FSF).
[0006] A disadvantage of the methods known from the related art is that the printed aluminum paste layer must be app. 40 μm thick (after the sintering), in order to obtain sufficiently deep alloy formation or aluminum doping depth. Due to the bimetallic effect between it and the silicon wafer, a reduction in the wafer thickness below the 180 μm typical up to now results in wafer deformation (so-called bow) that is no longer tolerable. High costs for the solar cell result from the necessary thickness of the silicon wafer and the amount of silicon consequently needed.
[0007] The screen-printed metallic coating of the back side has an imperfect reflection factor of only 65% for the long-wave portions of the sunlight, which penetrate to the back side. An effective reflectivity of >90% would increase the optical path length of the incident light and, therefore, the generation of electron-hole pairs (that is, the current) in the interior of the cell. Consequently, a marked gain in efficiency would be obtained.
[0008] In spite of the field passivation by heavy doping, a metallic surface, both that of an emitter and that of a back surface field (BSF), has a large charge-carrier recombination rate. In order to allow more effective passivation of the aluminum-doped surface of the back side, the thick, screen-printed aluminum layer needed as a dopant source and the AlSi eutectic layer formed between it and the semiconductor surface must be etched off. In the previously known methods, a large amount of hydrochloric acid is necessary for that purpose, due to the thickness of the layers to be etched off. This constitutes a large waste disposal problem.
BRIEF SUMMARY OF THE INVENTION
[0009] The subject matter of the present invention is a method for manufacturing a solar cell from a p-doped or n-doped silicon substrate, which has a first main surface used as an incident-light side in a state of operation, and a second main surface used as a back side; the method including the following steps: depositing a thin layer, which mainly includes aluminum, onto the second main surface; depositing a dielectric, glass-forming paste onto the second main surface and drying it, in order to cover the thin layer; heating and/or sintering the paste on the second main surface, in particular, at temperatures greater than app. 577° C., in order to produce an aluminum dopant layer in the second main surface; and removing the glass layer formed during the heating and/or sintering, as well as an aluminum-silicon eutectic layer formed during the heating and/or sintering, from the second main surface, through which the aluminum dopant layer is exposed.
[0010] An advantage of this method is that a solar cell, which has an aluminum dopant layer on the back side and allows passivation of the aluminum-doped back side, is manufactured in a technically simple and inexpensive manner. A further advantage of this is that the aluminum layer is deposited so as to be in direct contact with the entire main surface. In this manner, in the case of melting at the eutectic point, the entire amount of aluminum in the layer may be used directly, that is, without delay and/or without hindrance, for forming a melt. The aluminum-silicon melt flows uniformly on the entire second main surface. In addition, the aluminum layer is completely covered by the glass layer, so that when the aluminum-silicon eutectic melts, the melted layer is not exposed at any place. This means that coalescing to form drops, spattering and/or oxidizing are substantially prevented. Since the glass layer is intended as a temporary cover for the thin aluminum layer and is removed again after the doping, the thickness may be selected to be as low as possible. Thus, the glass layer may be removed again more easily and more rapidly. It is also advantageous that the glass layer has a low expansion coefficient that is similar to the silicon of the silicon substrate, which means that bowing of the silicon substrate is substantially prevented. Therefore, the silicon substrate may have a markedly lower thickness. Together, these result in the efficiency of the solar cell being higher and the manufacturing costs of the solar cell being markedly reduced.
[0011] The heating and/or sintering may proceed at a temperature of at least 800° C. By this means, it is ensured that the aluminum layer forms, together with the silicon, a liquid aluminum-silicon eutectic layer.
[0012] In the method, the paste may be applied by printing, in particular, by screen printing. By this means, the costs of the method may be reduced further.
[0013] In one specific embodiment of the method, the glass layer and the aluminum-silicon eutectic layer are etched away from the second main surface, using, in particular, hydrofluoric acid and hydrochloric acid, respectively. An advantage of this is that the layers are uniformly removed from the second main surface, using a proven method. In addition, it is advantageous that less hydrochloric acid is needed due to the low thickness of the aluminum-silicon eutectic layer, which lowers the costs and the degree of complexity, since the disposal of hydrochloric acid is very expensive and complicated.
[0014] In the method, metallic contact tracks for contacting the silicon substrate, and optionally, bus bars for electrically connecting the metallic contact tracks, may be deposited onto the first main surface; during the heating and/or sintering of the paste on the second main surface, the metallic contact tracks and the optional bus bars being simultaneously heated and/or sintered. The charges near the first main surface are collected by the metallic contact tracks, and the charges of a plurality of metallic contact tracks are collected by optional bus bars. Furthermore, it is advantageous that by jointly heating or sintering the metallic contact tracks and the optional bus bars and the paste on the second main surface, an additional step, which would be necessary for heating and/or sintering the metal contact tracks and the optional bus bars, is eliminated.
[0015] The metallic contact tracks and optional bus bars may be deposited by printing a silver paste and/or spraying on an aerosol ink containing silver and/or extruding a silver paste from thin tubes. A uniform thickness of the metallic contact tracks and optional bus bars is ensured by these cost-effective methods for depositing the metallic contact tracks and optional bus bars.
[0016] In a further specific embodiment of the method, prior to depositing the paste onto the second main surface, a thin dielectric layer, in particular, including an oxide and/or a nitride, is also deposited onto the thin layer to prevent oxidation of the aluminum of the thin layer by air. By this means, it is ensured that the thin aluminum layer is not oxidized, which would have a negative effect on the production of an aluminum eutectic or the aluminum dopant layer.
[0017] In a further specific embodiment of the method, after the aluminum dopant layer is exposed, a passivation layer is also deposited onto the second main surface, the passivation layer is removed from regions of the second main surface to form openings, and, using, in particular, a PVD method, preferably, sputtering and/or vapor deposition, a further aluminum layer is deposited onto the second main surface, in order to contact the aluminum dopant layer in the openings. The efficiency of the solar cell is increased by the passivation layer. In addition, it is advantageous that the second main surface of the silicon substrate is contacted by the further aluminum layer in a technically simple manner. Also, the no-load voltage may be increased. Furthermore, compared to a porous aluminum layer, the passivation layer and the further aluminum layer form, together, an improved infrared light mirror on the second main surface, through which a higher current yield per cell is obtained.
[0018] The passivation layer may be removed from regions of the second main surface, using laser ablation, etching paste and/or ion etching. By this means, the costs and the degree of complexity of the method are further reduced, since proven methods for removing the passivation layer are used.
[0019] In the method, a base layer containing nickel may also be deposited onto the further aluminum layer of the second main surface, in order to allow it to be built up chemically and/or galvanically. By this means, the deposition of further layers onto the second main surface is facilitated considerably.
[0020] In the method, after the deposition of the aluminum layer and the optional nickel-containing layer onto the second main surface, an insulating layer may also be deposited onto the second main surface, and using, in particular, laser ablation, etching paste and/or ion etching, the insulating layer may be removed from regions of the second main surface to re-expose the soldering surfaces, in order to allow subsequent chemical and/or galvanic building-up of the soldering surface openings. By this means, it is ensured that deposited layers for building-up are limited to the soldering surface openings, that is, that deposition of further layers onto only the soldering surface openings is made considerably easier.
[0021] In the method, a solderable layer or sequence of layers including, in particular, nickel, silver, copper and/or tin, may also be galvanically and/or chemically deposited onto the metallic contact tracks of the first main surface and the soldering surface openings of the second main surface; the building-up layer of the first main surface also being able to be different from the layer of the second main surface. By this means, soldering surfaces, which may easily be contacted via soldering, are produced in order to electrically contact the second main surface of the silicon substrate.
[0022] The subject matter of the present invention also includes a solar cell made from a p-doped or n-doped silicon substrate, which has a first main surface used as an incident-light side in a state of operation, and a second main surface used as a back side; the second main surface having an aluminum dopant layer, and the silicon substrate having a thickness of less than app. 200 μm, in particular, less than app. 180 μm. An advantage of this solar cell is that due to the lower thickness, less silicon is needed for the silicon substrate, which reduces costs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1-FIG . 14 show cross-sectional views of a silicon substrate after different steps of a method according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0024] In the following description, like reference numerals are used for parts that are identical or function in the same manner.
[0025] FIG. 1 shows a cross-sectional view of a silicon substrate 1 , which is used as a starting silicon substrate for the method of the present invention. Silicon substrate 1 has a first main surface 2 , which is used as an incident-light side in a state of operation, and a second main surface 3 , which is used as a back side in the state of operation. Silicon 4 of silicon substrate 1 is n-doped or p-doped. Silicon 4 of silicon substrate 1 may be monocrystalline or polycrystalline. First main surface 2 and second main surface 3 have been etched to remove saw damage. In addition, silicon substrate 1 has been textured on both sides. A phosphorus dopant layer 5 is situated in first 2 and second main surface 3 . Phosphorus dopant layer 5 was produced, for example, by diffusion and a subsequent driving-in step. After that, the phosphorus silicate glass produced by the diffusion and subsequent driving-in step was removed from the two main surfaces 2 , 3 .
[0026] FIG. 2 shows silicon substrate 1 after a first step of the method according to the present invention. In this connection, an antireflection layer or antireflection layer sequence 6 was deposited onto first main surface 2 of silicon substrate 1 , for example, by oxidation and/or PECVD methods or other known methods. Antireflection layer or antireflection layer sequence 6 includes a silicon nitride layer and/or a silicon oxide/silicon nitride layer sequence. This is additionally used as a passivation layer of the first main surface.
[0027] FIG. 3 shows a cross-sectional view of silicon substrate 1 after a further, optional method step. In the method step, phosphorus dopant layer 5 of second main surface 3 is etched away. By this means, the texturing of second main surface 3 is also smoothed out. Potassium hydroxide solution or HF/HNO 3 is preferably used for this. If phosphorus dopant layer 5 of second main surface 3 is not removed, the subsequent doping with aluminum must over-compensate for the phosphorus doping of second main surface 3 . In addition, without this optional method step, the texture of second main surface 3 is retained.
[0028] In the next method step, a thin aluminum layer 7 of a few micrometers, which is as pure as possible, is deposited onto second main surface 3 . An aluminum layer 7 , which is as pure as possible, is to be understood as a layer that essentially contains only aluminum. Thin aluminum layer 7 is deposited over the entire second main surface 3 , for example, by vapor deposition or sputtering, up to a distance from the edge of silicon substrate 1 that is as short as possible. The distance from the edge may also be zero. FIG. 4 shows silicon substrate 1 after this method step. The thickness of thin aluminum layer 7 is selected with regard to the desired depth of the aluminum dopant layer 8 produced in a subsequent method step. The depth of aluminum dopant layer 8 may be between 1 μm and 10 μm. Aluminum dopant layer 8 acts as an emitter or as a back-surface field as a function of the doping of silicon substrate 1 .
[0029] A cross-sectional view of silicon substrate 1 after a further, optional method step is shown in FIG. 5 . In the sputtering or vapor deposition system used for depositing thin aluminum layer 7 , for example, thin aluminum layer 7 may be covered with a thin dielectric layer 9 , which preferably includes an oxide and/or a nitride. In this manner, it is ensured that substantially no oxidation of the aluminum of thin aluminum layer 7 by air takes place.
[0030] In the next method step, metallic contact tracks 10 , so-called metal fingers, and optional collecting bars, so-called bus bars, are deposited onto first main surface 2 . The width of metallic contact tracks 10 or metal fingers is as small as possible. FIG. 6 shows a cross-sectional view of silicon substrate 1 after this deposition. The deposition may be accomplished, using one of the methods known from the related art. Metallic contact tracks 10 and the bus bars are preferably printed with a silver paste, sprayed using aerosol ink containing silver, or extruded from thin tubes.
[0031] First main surface 2 may be provided with, or have, selective doping, i.e., doping at a higher dopant concentration and/or a dopant layer extending deeper into silicon substrate 1 , in particular, underneath the metallic contact tracks and/or bus bars.
[0032] FIG. 7 shows a cross-sectional view of a silicon substrate 1 after the next method step. In this method step, a dielectric, glass-forming paste 11 is deposited onto the entire second main surface 3 and dried. Paste 11 covers thin aluminum layer 7 completely. This cover of thin aluminum layer 7 is intended to be a temporary cover during the method and is removed again after second main surface 3 is doped with aluminum. Therefore,
[0000] the thickness of deposited paste 11 is selected to be as low as possible. The thickness is typically 10 μm-12 μm.
[0033] In the next method step, paste 10 and glass-forming paste 11 are simultaneously sintered or heated on first main surface 2 and second main surface 3 , respectively, at temperatures preferably above 800° C.; the paste being sintered or heated to form metallic contact tracks and optional bus bars. When heated above 577° C., thin aluminum layer 7 and silicon 4 form a liquid eutectic AlSi phase at second main surface 3 . FIG. 8 shows a cross-sectional view of silicon substrate 1 after this method step. At each time, the thickness of the liquid eutectic layer under glass paste 11 or glass cover 12 is a function of the temperature presently prevailing and the thickness of thin aluminum layer 7 . After briefly heating it above 800° C., in response to cooling off to below the eutectic temperature (app. 577° C.), the aluminum-doped crystalline layer recrystallizes from the inside to the outside to form a p + layer, which constitutes the emitter in the case of an n-doped silicon substrate 1 , and the back-surface field in the case of a p-doped silicon substrate 1 . FIG. 8 shows a cross-sectional view of silicon substrate 1 after this method step, in which an aluminum dopant layer 8 is formed on second main surface 3 . Glass paste 11 or glass cover 12 prevents oxidation of the liquid AlSi eutectic layer.
[0034] The remaining eutectic melt in the form of boundary phases of the phase diagram subsequently solidifies to form the AlSi layer having a granular structure. After the doping of second main surface 3 with aluminum, all of the layers on second main surface 3 above aluminum dopant layer 8 are removed. To this end, dielectric layer 12 and optional dielectric layer 9 are initially etched off using hydrofluoric acid, and the remaining layers containing AlSi and aluminum are subsequently etched off using a suitable acid. The silicon substrate 1 after this method step may be seen in FIG. 9 . The layers on first main surface 2 are essentially not attacked by this etching operation.
[0035] Since the glass layer is only needed temporarily, its thickness may be selected to be as small as possible, preferably, between 10 μm and 12 μm. Because of the lower thickness, less acid is required for re-dissolving or removing this layer. In comparison with the removal of a 40 μm thick aluminum layer or screen-printed aluminum layer according to the related art, an amount of acid, in particular, hydrofluoric acid, is needed that is lower by at least a factor of 4.
[0036] The newly exposed silicon surface of second main surface 3 , which is doped with aluminum, is now coated with a passivation layer 13 suitable for p + -doping (see FIG. 10 ). Subsequently, passivation layer 13 is locally opened using a known method, for example, using laser ablation, etching paste and/or ion etching. In this context, the regions (openings 15 for local contacts and soldering surface regions 17 ), at which the solderable metallic surfaces (collecting bars or bus bars or soldering contact surfaces) are supposed to be deposited on second main surface 3 in later method steps, are also exposed. A cross-sectional view of the silicon substrate 1 having locally opened passivation layer 13 may be seen in FIG. 11 .
[0037] The entire second main surface 3 is subsequently covered with a further aluminum layer 14 , using a PVD method known from the related art, e.g., by sputtering or vapor deposition. Further aluminum layer 14 is sufficiently thick and directly contacts aluminum dopant layer 8 of second main surface 3 of silicon substrate 1 in the open regions or openings 15 , 17 , and in all of the other regions of second main surface 3 , it is situated on passivation layer 13 . FIG. 12 shows a cross-sectional view of silicon substrate 1 after this method step. In the same PVD system, a thin layer containing nickel is advantageously deposited onto further aluminum layer 14 , in order to be able to more easily deposit, later in the method, a solderable layer in the bus-bar regions or soldering contact surface regions, in a chemical or galvanic process.
[0038] In a further method step, in the same system, a thin dielectric or insulating layer 16 is deposited onto the entire second main surface 3 , in order to limit the building-up to the soldering surface regions. Using one of the known methods (laser ablation, etching paste, ion etching), this dielectric insulating layer 16 is subsequently opened in the soldering surface regions to form soldering surface openings 17 . The silicon substrate after this method step may be seen in FIG. 13 . By this means, subsequent chemical and/or galvanic building-up 18 exclusive of soldering surface openings 17 is rendered possible or made easier.
[0039] As a final method step, metallic contact tracks 10 of first main surface 2 and soldering contact surfaces 17 of second main surface 3 are built up with a solderable layer sequence 18 , 19 . This solderable layer sequence 19 is made up of a suitable combination of the metals nickel, silver, copper and/or tin. The deposition of solderable layer sequence 19 may be accomplished galvanically or chemically. FIG. 14 shows a cross-sectional view of silicon substrate 1 after this last method step.
[0040] At this point, it is emphasized that all of the above-described steps of the method, alone and in any combination, in particular, the details illustrated in the drawing, are claimed as essential to the present invention. Modifications to them are familiar to one skilled in the art.
[0041] In all other respects, the implementation of the present invention is not limited to the above-described examples and emphasized aspects, but only by the scope of protection of the appended claims.
|
A method for manufacturing a solar cell from a p-doped or n-doped silicon substrate having a first main surface used as an incident-light side and a second main surface used as a back side includes: depositing a thin layer onto the second main surface; depositing a dielectric, glass-forming paste onto the second main surface and drying it, in order to cover the thin layer; heating and/or sintering the paste on the second main surface at temperatures greater than app. 577° C., to produce an aluminum dopant layer in the second main surface; and removing the glass layer formed during the heating and/or sintering, as well as an aluminum-silicon eutectic layer formed during the heating and/or sintering, from the second main surface.
| 8
|
CROSS REFERENCE
This present application has a parent copending application by the same inventors, namely U.S. patent application No. 862,751 filed Dec. 23, 1977, now abandoned, which is hereby incorporated by reference, and a grandparent application by the same inventors which was copending with the parent application but has since been abandoned, namely U.S. patent application No. 854,617 filed Nov. 25, 1977, now abandoned, the benefit of the filing dates of both of which prior applications are claimed under 35 USC 120.
SUMMARY OF THE INVENTION
Our invention relates to a line blind.
A purpose of our invention is to prevent leakage in connection with the line blind, where it is especially important.
A further purpose of the invention is to make sure that if any seal in the line blind should develop any tendency to leak, this can normally be promptly and readily overcome by a minimum of action which will not even require replacement of the seal.
A further purpose is to provide a line blind which is especially easy and inexpensive to install and replace in a condition of perfect effective lineal and angular alignment and in which any danger of leakage due to misalignment of any kind will be minimized.
Other purposes will be apparent from the remainder of the description and the claims.
SHORT DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an elevational view partly broken away, taken horizontally and at right angles to the direction of flow in the pipe, of the preferred particular embodiment of our invention, involving line blind, with optional flanges shown in phantom.
FIG. 2 shows an end elevational view of the same embodiment as FIG. 1, taken longitudinally of the pipe, with a showing of other positions for some of the components also in phantom.
FIG. 3 shows a perspective exploded view from above and to the left, of the same embodiment as FIGS. 1 and 2, but leaving off the annular outer members which hold the seal rings and camming setup on, and showing the seal as if unitary in construction, for simplicity of illustration.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Describing in illustration and not in limitation, and referring to FIGS. 1 through 3:
In this form of embodiment, which involves line blind 20, the device includes a closure setup in the form of spectacle plate 22, which includes at one end a continuous plate 24 for closing off body pipe 26 when desired, and at the other end a circular opening 28 for permitting flow through the pipe when desired, being swung around pivot 30, which passes through its intermediate portion 46, into either of these positions, all as of course per se already well known. Detent 32 serves to hold it in whatever place is selected. Body pipe 26 is a special length of pipe which is intended to be butt welded at the ends into the longer length pipe which the line blind is intended to control, and optionally may have flanges 34 and flange inserts 36 at its ends.
Body flanges 40, more or less triangular in shape, one on either side of the spectacle plate, are held together by bolts 42, one at each corner of the triangle, with suitable nuts 44 at the end. The topmost of the bolts serves as pivot 30 of the spectacle plate.
Outside of the body pipe in its portion within the body flanges is an encircling structure which includes on one side of the spectacle plate stationary annular member 48, which holds against the spectacle plate stationary seal ring 50 which is located in a recess in the inner rim of the annular member on its face toward the spectacle plate. This and the other seal ring used in our device are preferably mostly of some suitable resilient material, such as teflon, together with one or more inserts located against the plate which are made of some more rigid material such as stainless steel. The resilient material likewise comes against the plate in between the inserts and extends further back than and behind the inserts.
On the other side of the spectacle plate, there is also a seal ring 52, preferably of similar type, radially to the inside of one end 73' of outer annular member 75, the end nearest the spectacle plate.
Cam assembly 54 is likewise radially to the inside of that annular member, but away from the spectacle plate as compared to the seal ring 52.
Cam assembly 54 has two cooperating special cams, 62 and 64. Cam 62 is next to and beyond the seal ring 52, longitudinally speaking from the spectacle plate, and in the direction away from that ring has a toothed surface 66 in which a series of gradually sloping surfaces 68 on the longitudinal annular end facing away from the seal ring are separated from each other by abruptly rising tooth surfaces 70 in between.
Cam 64 has a similar toothed surface 72 facing the toothed surface of cam 62, with each tooth of cam 64 fitting into the hollow formed between teeth of cam 62, and each gradually sloping surface 73 of cam 64 corresponding in one position to and facing such a surface of cam 62, once allowance is made for the slight staggering effect of the interfitting as between teeth. The overall effect of the arrangement can be best seen in FIG. 3.
Cam 62 is held in its rotational position by four equally spaced pins 74 extending radially outwardly from its outside surface, riding in longitudinal slots as at 77, which extend deep into outside ring 75, while at the same time the longitudinal direction of the slots permits movement of cam 62 in the longitudinal direction of the pipe.
The back of cam 64, away from its toothed surface, is against the inner face of the nearest body flange 40, while annular member 48 has its far face against the corresponding inner face of the other body flange 40, and the face of seal ring away from the spectacle plate is against the bottom of the recess in the near face of annular member 48.
Cam 64 has a radially outwardly extending actuator arm 76, whose position is fixed by some particular suitable device, such as positioning device 78 which is shown in the drawings. As will be evident from what is there shown, T-member 80 includes a T-head in the form of a tubular cylinder adapted to have some suitable bar inserted in the tube for turning purposes and a cylindrical T-leg ending away from the head in stepped down stem 82 threaded on the outside. Extending beyond this stem toward the actuator is exteriorly threaded arm 86, which extends into the stem from the end, in cooperation with interior threads in the stem. On the end toward the actuator of the arm 86 is flat piece 90 having a hole for pin 88 extending through it between holes in end 92 of actuator arm 76, to attach it to that actuator arm. Stem nut 84 on the outside threads of stem 82 can be tightened against a lug on the bottom of body flange 40 to hold the T-member fixed at whatever position is desired for actuator arm 76.
Cam assembly 60 should have, in each of its cam elements, from 3 through 30 teeth interfitting with those in the other element, as shown in the drawings, and will preferably have 18, so that the circumferential structure of a given element would start to repeat itself every 20 degrees.
The slope of the gradually sloping surface will preferably be uniform, and should be in the range from 5 through 20 degrees, and preferably 121/2 degrees, such a surface being for example 70'.
In operation, of course, the spectacle plate essentially is intended to assume one of two positions, a position such as found in FIGS. 2 and 3, in which the plate closes off the line, and a position in which the spectacle plate is swung around an arc of 180° to remove the closed end of the spectacle plate from its position in the line and substitute instead the open end of the spectacle plate, thus permitting free flow through the line.
When it is desired to close the line off and the continuous plate of the spectacle plate is brought across the line, the positioning device can be operated to bring the actuator arm to somewhat rotate cam 64 to bring its teeth less in alignment with the teeth of cam 62, so that their gradually sloping parts of their faces will be contacting each other at points relatively higher up the gradual slopes. This will force cam 62 toward seal ring 52 along a longitudinal path dictated by the pins 74 being confined in their respective longitudinal slots. This will force seal ring 52 tight against plate 24 of the spectacle plate, which in turn will force that plate against seal ring 50 on the other side of that plate, as a result of which the entire circumferential portion of the line will be sealed, to securely and effectively prevent any possibility of leakage around the line blind.
The present invention in line blinds has an especial advantage in that it can very readily be installed or replaced, without the extremely close adjustment required in ordinary line blinds to insure that alignment of the pipeline both laterally and angularly is secured, in order to prevent any possibility of leakage due to misalignment. This is very important in line blinds, whose primary function is likely to be to insure the safety of people down the line by completely blocking off the line and anything flowing in it.
In view of our invention and disclosure, variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art to obtain all or part of the benefits of our invention without copying the apparatus shown, and we, therefore, claim all such insofar as they fall within the reasonable spirit and scope of our claims.
|
A line blind includes seal rings on either side of a spectacle plate interposed in a pipe, and a special camming arrangement including two cooperating sets of longitudinally directed sloping teeth circularly arranged which operate on slight rotational movement of one, while the other is held stationary, to force engagement under pressure between the seal rings and the plate.
| 5
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Patent Application Ser. No. 61/247,722 and U.S. Patent Application No. 61/251,381, the disclosures of which are incorporated herein by reference in their entireties.
BACKGROUND
1. Field of Technology
The present disclosure relates to surgical handpieces, and specifically surgical handpieces that provide user friendly cleaning and sterilization.
2. Related Art
Surgical handpieces used to drive cutting tools during a surgical procedure, such as the handpiece and cutting tools shown in U.S. Pat. No. 5,871,493 ('493 patent), which is incorporated herein by reference in its entirety, are currently available. These handpieces have design features that make cleaning and sterilizing of the handpiece a challenge. Specifically, the areas around the cutting tool connection and the entry to the aspiration channel are hard to access and have a potential for not being properly cleaned prior to sterilization. Therefore, handpieces that lend themselves to user-friendly cleaning and sterilization are needed.
SUMMARY
In an aspect, the present disclosure relates to a surgical handpiece including an insert removably coupled to the handpiece, wherein the insert is configured to allow aspiration of fluid and tissue through the insert during a surgical procedure. In an embodiment, the handpiece includes a groove configured for housing of the insert. In another embodiment, the insert includes a distal portion and a proximal portion, wherein the proximal portion is configured for engagement with a suction device. In yet another embodiment, the insert includes at least one tab, wherein the tab is configured for disposal within an opening of the handpiece. In a further embodiment, the insert includes at least two tabs, wherein the tabs are configured for disposal within openings of the handpiece. In yet a further embodiment, the handpiece includes an aspiration channel, wherein the channel is located in-line with the groove so as to allow aspiration of the fluid and tissue through the channel and into the insert.
In an embodiment, the handpiece includes a valve removably coupled to the handpiece, wherein the valve is configured to be located in a first position or a second position. In another embodiment, locating the valve in the first position allows for aspiration of the fluid and tissue through the channel and the insert and locating the valve in the second position does not allow for aspiration of the fluid and tissue through the channel and the insert. In another embodiment, the handpiece includes an access port. In yet another embodiment, the handpiece includes a cover disposed within the access port.
In another aspect, the present disclosure relates to a surgical handpiece including an insert removably coupled to the handpiece, wherein removal of the insert allows for access to an inner area of the handpiece. In an embodiment, the inner area includes a drive shaft and entry to an aspiration channel. In another embodiment, the insert is coupled to the handpiece via a snap-lock assembly.
In yet another aspect, the present disclosure relates to a method for the removal of tissue during an endoscopic procedure. The method includes providing an assembly including a surgical handpiece including an insert removably coupled to the handpiece; and a cutting tool coupled to the handpiece; and inserting the cutting tool into an area of the body to cut the tissue and remove the tissue via the assembly.
In an embodiment, the tissue is removed via the insert. In another embodiment, the method further includes removing the insert from the handpiece and replacing the insert with another insert. In yet another embodiment, a suction device is coupled to the insert for removal of the tissue. In a further embodiment, the method further includes removing the insert from the handpiece to allow for access to an inner area of the handpiece, the inner area including a drive shaft and an aspiration channel. In yet a further embodiment, the method further includes cleaning the inner area of the handpiece. In an embodiment, the surgical handpiece includes an access port and a cover disposed within the access port, wherein the method further includes removing the cover and cleaning an inner area of the handpiece.
Further areas of applicability of the present disclosure 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 disclosure, are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present disclosure and together with the written description serve to explain the principles, characteristics, and features of the disclosure. In the drawings:
FIG. 1 shows a perspective view of a first embodiment of the surgical handpiece of the present disclosure.
FIG. 2 shows an exploded view of the surgical handpiece of FIG. 1 .
FIG. 3 shows a perspective view of the surgical handpiece of FIG. 1 without the insert.
FIG. 4 shows a cross-sectional view of the surgical handpiece of FIG. 1 without the insert.
FIG. 5 shows a perspective view of a cutting tool for use with the surgical handpiece of FIG. 1 .
FIG. 6 shows a side view of a second embodiment of the surgical handpiece of the present disclosure.
DETAILED DESCRIPTION OF THE EMBODIMENTS
The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the disclosure, its application, or uses.
FIGS. 1-4 show a first embodiment of the surgical handpiece 10 of the present disclosure. The handpiece 10 includes a body 11 having a distal end 11 a and a proximal end 11 b . At its distal end 11 a , the handpiece 10 includes a cylindrical bore 12 for coupling of a surgical cutting tool 20 ( FIG. 5 ). Within the bore 12 is a drive shaft 13 that is coupled to a motor 14 positioned within the handpiece 10 . The handpiece 10 includes pushbutton switches 15 that produce signals for use in controlling the motor 14 . The handpiece 10 is employed within a surgical system and method, the components and steps of which are shown and described in the '493 patent. The handpiece 10 is coupled to the rest of the system by a cable 16 that is coupled to the proximal end 11 b of the handpiece 10 . The cable 16 may be coupled via a connector, such as a threaded connector, as shown and described in the '493 patent.
The surgical cutting tool 20 , which is further described in the '493 patent, includes an inner cutting member 21 disposed within an outer cutting member 22 . The instrument 20 is coupled to the handpiece 10 to create an assembly such that the hubs 21 a , 22 a of the members 21 , 22 are disposed within the bore 12 . The assembly is used to cut and remove tissue from an area of the body during a surgical procedure. The hub 21 a of the inner cutting member 21 includes an opening 21 b that permits material, such as fluid and tissue, drawn through member 21 to pass into an aspiration channel 17 of the handpiece 10 . The handpiece 10 also includes a handle 18 that controls a valve 19 and thereby controls flow through the aspiration channel 17 . The handle 18 rotates about an axis 100 that is perpendicular to a longitudinal axis 200 of the handpiece 10 between a first position, wherein the handle 18 is pushed forward toward the distal end 11 a , as shown in FIG. 1 , and a second position, wherein the handle 18 is pushed backward toward the proximal end 11 b . Having the handle 18 in the first position allows for opening of the valve 19 and having the handle 18 in the second position allows for closing of the valve 19 or vice versa. The handle 18 and valve 19 are both removably coupled to the handpiece 10 via a coupling method described in the '493 patent or other method known to one of skill in the art.
An insert 30 is located within a groove 11 c of the body 11 such that the insert 30 is located in-line with the aspiration channel 17 . The insert 30 includes a distal end 31 , a proximal end 32 , a cannulation 33 that extends the entire length of the insert 30 , and tabs 34 coupled to the insert 30 . The insert 30 is located within the groove 11 c such that the tabs 34 are disposed within openings 11 d in the body 11 . The insert 30 may be placed within the groove 11 c by placing the distal end 31 into the groove 11 c via the opening 11 c ′ and pushing the insert 30 longitudinally towards the distal end 11 a of the handpiece 10 until the tabs 34 are located within the openings 11 d . During placement of the insert 30 into the groove 11 c , the tabs 34 may be reduced radially, by squeezing the tabs 34 inwardly toward the insert 30 to fit within the opening 11 c ′. For the purposes of this disclosure, there are two tabs 34 and two corresponding openings 11 d . However, there may be only one tab and one corresponding opening or more than two tabs and corresponding openings. It is also within the scope of this disclosure to not have any tabs 34 or openings 11 d . An o-ring 40 may be located on the distal end 31 of the insert 30 in order to provide a seal and substantially reduce leakage of fluid and tissue from the aspiration channel 17 , as will be further described below.
The proximal end 32 of the insert 30 includes a spigot 35 . During use, the spigot 35 is coupled to a source of suction (not shown), such that when the valve 19 is located in an open position, fluid and tissue are aspirated through the insert 30 . After use, the insert 30 may be removed from the groove 11 c in order to allow access to the aspiration channel 17 , especially the portion of the aspiration channel 17 in which the valve 19 is located, thereby allowing the user to clean and sterilize these areas. Once these areas have been cleaned and sterilized, a new insert may be placed within the groove 11 c and the old insert may be discarded.
Additionally, the body 11 includes an access port 50 located towards the distal end 11 a of the body 11 . A cover 60 is located within the access port 50 to close the port 50 during use. After use, the cover 60 is removed in order to allow access to the inner area of the handpiece 10 , such as the bore 12 and the components within the bore 12 , such as the drive shaft 13 , thereby allowing the user to clean and sterilize these areas and components. After these areas are cleaned and sterilized, the cover 60 may also be cleaned and then re-inserted in the port 50 .
FIG. 6 shows a cross-sectional view of a second surgical handpiece 300 of the present disclosure. The handpiece 300 is similar to handpiece 10 , except for having an insert 400 removably coupled to the distal end 301 a of the handpiece 300 . The handpiece 300 may or may not additionally have the groove 11 c and insert 30 combination of handpiece 10 . The handpiece 300 may include a latch 310 having a tab 310 a that engages an opening 410 of the insert 400 and acts as a snap-lock assembly to couple the insert 400 to the handpiece 300 . Similar to the cover 60 of the handpiece 10 , the insert 400 covers the inner area of the handpiece 300 , such as the bore 302 and the components within the bore 302 , such as the drive shaft and the aspiration channel (not shown). During use, the insert 400 is attached to the handpiece 300 . However, after use, the insert 400 is removed to allow the user to clean and sterilize the inner area and its components. After cleaning and sterilization, the insert 400 may also be cleaned and then re-attached to the handpiece 300 . However, the insert 400 may be disposed of and another insert may coupled to the handpiece 300 .
For the purposes of this disclosure, the inserts 30 , 400 of the handpieces 10 , 300 are plastic. However, other materials could also be used. Also, the inserts 30 , 400 may be made via a process, such as injection molding, die drawing, or any other process known to one of skill in the art. The cover 60 is made using similar materials and via similar processes. The groove 11 c , openings 11 d , and access port 50 may be made via a machining process or another process known to one of skill in the art.
As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the disclosure, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.
|
The present disclosure relates to a surgical handpiece including an insert removably coupled to the handpiece, wherein the insert is configured to allow aspiration of fluid and tissue through the insert during a surgical procedure. Other surgical handpieces and a method for the removal of tissue during an endoscopic procedure are also disclosed.
| 0
|
This application is a division of application Ser. No. 851,624, filed Nov. 15, 1977, now U.S. Pat. No. 4,307,880.
BACKGROUND OF THE INVENTION
The present invention relates to a device for exercising Yoga. More particularly, it relates to exercising in a candle-like posture.
It is well known that a Yoga practitioner must assume respective postures for performing respective Yoga exercises. However, up to now Yoga practitioners have assumed respective postures by themselves without the aid of specific devices. This possesses essential disadvantages which will be described hereinbelow. The Yoga exercises assure medical and restoring action only in the case when they are correctly performed. Since the Yoga exercises are substantially complicated to be performed, a person which is going to start exercising encounters many difficulties. Such person may have no time for lengthy studying, he or she may not be sufficiently persistent, he or she may have no trainer for providing competent help, he or she must spend essential time in order to arrive at correct postures, he or she may have some interruptions in studying which make the process even more complicated and return the practitioner back to initial condition, he or she may be unwell after incorrectly mastered posture, and he or she may have excessive weight or may be sick. In all these cases it is very difficult to exercise Yoga.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a device for Yoga exercising which make Yoga exercises more accessible for practitioners, as compard with the known methods.
More particularly, it is an object of the present invention to provide a device for Yoga exercising so that Yoga exercises may be correctly executed substantially independently from practitioner's age, weight, inclination and ability for exercising, persistance, interruptions in mastering the exercises, and without a trainer.
Another object of the present invention is to provide a device for Yoga exercising which has a simple construction and is easy and inexpensive to manufacture.
In keeping with these objects, and with others which will become apparent hereinafter, one feature of the present invention resides in a device for Yoga exercising which has a resiliently deformable element movable to a position in which it is convex so that the practitioner resting on said element from outside assumes a candle-like posture; and means for retaining this element in the convex position.
Another feature of the present invention is a method of forming the device comprising the steps of deforming a resiliently deformable element to assume a convex contour so that when the practitioner's body rests on the element from outside it assumes a candle-like posture and retaining the element in this convex position.
When the practicioner executes Yoga exercises with the aid of the above device and method he or she does not need to be preliminarily trained and can immediately execute the Yoga exercices. This possibility does not depend on practicioner's weight, age, inclination and ability for exercising, persistance, interruptions in exercising and the like. The practitioner does not need to be taught by a trainer. During short time he or she will be convinced in fact that the device is simple and helpful, and he or she is able to improve his or her health by Yoga exercising.
Still another feature of the present invention is that the retaining means may include an elongated connecting element bracing the resiliently deformable element in the convex position. The connecting element may be adjustable in the direction of elongation thereof so as to vary its length in order to connect respective portions of the resiliently deformable element and to vary curvature of the later. Such adjustable connecting element may include two sections telescopically movable relative to one another and fixable in a plurality of positions. The connecting element has a rigidity exceeding the rigidity of the resiliently deformable element.
A further feature of the present invention is that the connecting element may rigidly connect end portions of the resiliently deformable element with one another. The connecting element also may rigidly connect one of the end portions of the resiliently deformable element with a section located intermediate another end portion and a central plane of the resiliently deformable element. In the later case, the connecting element may be connected with the above section in a plurality of positions spaced from one another so that curvature of the resiliently deformable element can be varied. Both the above connections may be used simultaneously and together.
A still further feature of the present invention is that the resiliently deformable element may have two or more separate members connectable with one another so as to form together the resiliently deformable element. When the members are disconnected from one another the device will be more compact and convenient for transportation.
An additional feature of the present invention is that the resiliently deformable element may have a rectilinear contour in an initial position. It is also possible that the resiliently deformable element has a curved contour in the initial position, which contour has a radius of curvature exceeding the radius of curvature of the same in the first, second and third positions. In the third position, the resiliently deformable element has a tendency to assume its initial curvature and thereby urges the practicioner's body to bend forward.
A still additional feature of the present invention is that a base member may be detachably connected to the resiliently deformable element so that the practitioner may place his or her body on the base member before executing the exercises and the deformable element connected thereto cannot move away from the practitioner. The base member may have at least one face surface provided with engaging formations so as to prevent slipping of the resiliently deformable element relative to a floor or the like and of the practitioner's body relative to the base member. It is to be understood that both face surfaces of the base member may be provided with such engaging formations.
Other objects, features and advantages of the of the present invention will become apparent from the subsequent description, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1a and 1b are front and side views showing a Yoga exercising device in a convex position;
FIG. 2 is a view showing a connecting element including two sections movable relative to and connectable with one another;
FIG. 3 is a view showing a base member detachably connected to a resiliently deformable element of the Yoga exercising device;
FIG. 4 is a view showing a resiliently deformable element of the Yoga exercising device including two sections detachably connectable with one another; and
FIG. 5 is a view showing handles detachably connectable with the resiliently deformable element of the Yoga exercising device.
DESCRIPTION OF PREFERRED EMBODIMENTS
Yoga exercising device in accordance with the present invention has a resiliently deformable element I which may be constituted of any material having the above characteristic.
The deformable element I can be bent so as to assume a convex contour, as shown in FIG. 1 of the drawing. A connecting element 2 retains the deformable element I in this position. The connecting element 2 is detachably connected to the deformable element I so that one end portion of the former is connected to one end portion of the latter, whereas another end portion of the connecting element 2 may be connected to the deformable element I in one of a plurality of locations spaced from one another, as indicated in solid and broken lines in FIG. 1. Thus, the deformable member I can have different radii of curvature, and different resiliency of the latter. The connecting element 2 is connected to the deformable element I by conventional means, such as pivot means 3 shown in FIG. 1.
The deformable element I has a plurality of bores 4 spaced from one another in the direction of elongation thereof, in each of which bores 4 handles 5 shown in FIG. 9 may be detachably inserted. By means of the handles 5 the practitioner can vary stress applied thereto during the Yoga exercise.
It is also possible to provide in the device at least two such connecting elements. In this case, one of the connecting elements may connect the end portions of the resiliently deformable element I, whereas another connecting element may connect one of the end portions of the resiliently deformable element I with a section thereof located between the other end portion and the central plane of the resiliently deformable element I. The practitioner places his body outside the convex deformable element I so that he or she can assume a candle-like posture or Sarvangasana. The above handles 5 may be inserted in the bores 4 located adjacent to end portion of the deformable element I so that the practitioner can grasp the handles and assume as well as reliably retain himself or herself in this position. The end portions of the deformable element I may have leg sections. Spreaders 6 may be provided so as to support the device in stable condition. The device may abut against a wall 7 of the living unit.
The deformable element I may have two separate sections 8' and 8" detachably connectable with one another, as shown in FIG. 4. Thus-formed element can be easily dismounted. The device becomes compact and occupies a comparatively small space, for instance, for transportation.
A base member 9 may be detachably connected to the end portion of the deformable element I. The practitioner may sit or lie down on the base member 9 and thereupon start exercising. The base member cannot move away owing to the practitioner's weight applied thereto, and therefore the deformable element 1 is precented from moving away from the practitioner. One or both face surfaces of the base member 9 may be provided with engaging formations so as to prevent slipping of the base member 9 relative to a floor and the like and/or slipping of the practitioner's body relative to the base member.
The connecting element 2 may be adjustable in the direction of elongation thereof. For instance, the connecting element may be composed of two or more separate sections, such as 2' and 2", as shown in FIG. 2, which telescopically move relative to one another and are fixed in a plurality of mutual positions so that the length of the connecting element 2 may be varied. By varying the length of the connecting element 2 the curvature of the resiliently deformable element I can be varied, so that the practitioner can vary the curvature and angle of inclination of his or her body in the candle-like posture. In the latter case, the practitioner can gradually master a plurality of postures, starting from a posture with a small angle of inclination, and thereupon can gradually increase this angle. The connecting element 2 must have rigidity exceeding the rigidity of the deformable element I so as to brace the latter in a respective position.
The deformable element I in an initial or inoperative position may have a substantially rectilinear contour which subsequently will be changed by bending of the deformable element I into a respective position. It is to be understood that the practitioner can bend the deformable element I by himself or herself. On the other hand, the deformable element I may have in the initial condition a concave contour. In the latter case the deformable element I must be bent by the practitioner into a more curved contour as compared with that in the initial position. A radius of curvature of the deformable element I in the third position will be smaller than that in the initial position, and therefore the practitioner will be urged by the element I to bend forward.
The deformable element I may be adjustable in the direction of elongation thereof so as to vary its length. This can be done by means which are similar to the means shown in FIG. 2 for adjusting the length of the connecting element 2, or by other conventional means.
While it will be apparent that the preferred embodiments of the invention herein disclosed are well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modifications, variations and changes without departing from the proper scope or fair meaning of the subjoined claims. The device may also be used for executing other Yoga exercises which differ from those described above.
|
A device for exercising Yoga has an elongated resiliently deformable element movable to a position in which it is convex so that the practitioner resting on said element from outside assumes a candle-like posture and a connecting element retaining the resiliently deformable element in the above position. A method of forming the device includes the steps of respectively deforming and retaining the resiliently deformable element so that the practitioner's body can assume the candle-like position.
| 0
|
RELATED APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 08/684,117 filed Jul. 19, 1996 now U.S. Pat. No. 5,817,708.
FIELD OF INVENTION
This invention relates to a low volatile organic (VOC) solvent based adhesive. In particular, the invention relates to a low VOC solvent based adhesive which is capable of joining two thermoplastic materials together. Furthermore, the invention relates to a low VOC solvent based adhesive which volatilizes at a substantially reduced rate as compared to conventional solvent based adhesives for thermoplastic materials. Additionally, the invention relates to a low volatile organic solvent based adhesive having a flash point substantially above 100° F. as determined by the test method set forth in the ASTM D 3828-87. Preferably, the invention comprises a low VOC solvent based adhesive used to join two objects or articles made from chlorinated polyvinyl chloride (CPVC).
BACKGROUND OF THE INVENTION
Solvent based adhesives have been used extensively to join thermoplastic pipe and fittings for numerous years. These solvent based adhesives provide for a convenient way to join thermoplastic materials relatively easily and quickly. Often, thermoplastic pipe and fittings joined in this manner can even be tested the same day.
Generally, the solvent based adhesives comprise a solvent or mixture of solvents as well as resin and other additives such as thixotropic agents. The solvent based adhesive dissolves the surface layer of the thermoplastic material to which it is applied, causing it to swell. The resin in the adhesive solution accelerates the setting of the two materials to be joined as well as reduces the internal stresses. As the adhesive cures by evaporation, the diffusion of the solvents bonding of the mated surfaces occurs. The primary solvents used in conventional solvent based adhesives include tetrahydrofuran, methyl ethyl ketone and cyclohexanone. These solvents are very volatile and adhesives made therefrom have VOC levels in the range of 750 to 850 g/l as measured by the South Coast Air Quality Management District (SCAQMD) 316A. Furthermore, prior to the application of these conventional solvent based adhesives, the thermoplastic material must be prepared with either a primer such as tetrahydrofuran or a cleaner such as acetone, in order for the adhesive to be effective. Therefore, even more volatile organic compounds are released into the atmosphere. In addition, since these conventional solvent based adhesives are largely formed from solvents, the solvent tends to spread to a large area and drip in their application to the thermoplastic materials, causing additional volatization. Moreover, conventional solvent based adhesives and/or primers for adhesives generally have low flash points. The low flash point requires special precautions in the handling and packaging of these adhesives and/or primers. The following patents and references are examples of conventional solvent based adhesives and/or primers for adhesives for thermoplastic materials.
U.S. Pat. No. 3,726,826 discloses a stabilized adhesive solution for polyvinyl chloride. The solution comprises 5 to 25 weight percent of a post-chlorinated polyvinyl chloride resin in tetrahydrofuran and from 0.4 to about 5 weight percent of 1,2-butylene oxide.
U.S. Pat. No. 4,098,719 to Hushebeck describes a primer to be used in the assembly of polyvinyl chloride (PVC) pipe and fitting or PVC pipe and fittings to acrylonitrile-butadiene-styrene (ABS) pipe or fittings. The primer consists essentially of from 0.5 to about 2.5 percent by weight of an unplasticized polyvinyl chloride resin dissolved in a solvent. The solvent is a mixture if tetrahydrofuran and dimethylformamide.
An addition example of a conventional solvent based adhesives can also be found in European Patent Application 0 489 485 A1 to Texaco Chemical Company. This application discloses a process for welding plastic materials. The materials are welded by applying alkylene carbonate in its pure form or as a mixture with a co-solvent such as aromatic hydrocarbons, ketones, esters, ethers, glycol ethers, imidazoles, tetramethyl urea, N,N'-dimethyl ethylene urea, 1,1,1 -trichloroethane and N-methyl pyrrolidone.
Furthermore, U.S. Pat. No. 4,910,244 describes a storage stable adhesive containing CPVC. The solvent based adhesive comprises 5 to 30 percent by weight of CPVC and 95 to 70 percent by weight of an organic solvent as well as a stabilizer. This mixture provides improved stability when stored in tin plated steel containers.
As seen from the brief descriptions of a sample of references describing conventional solvent based adhesives, these adhesives generally have a low solids content. Due to the high volatility and low flash points of the solvents comprising the major portion of the adhesive, these adhesives are, in turn, extremely volatile and flammable.
Evaporation of solvents from solvent based adhesives provides for an air pollution problem. The major portion of the solvent emission occurs during the application of the adhesive to the thermoplastic materials to be joined. In addition, a primer, itself a very volatile material, is also used to prepare the thermoplastic surfaces and therefore, there is additional solvent volatilized and released to the air. Furthermore, emission of the solvent also occurs from the container containing the solvent based adhesive which is usually kept open during the application of the adhesive to the thermoplastic materials. Finally, spills can occur during the application of the solvent based adhesive providing yet another means for the emission of volatile organic materials into the air.
Due to the environmental awareness occurring today, laws and regulations are being enacted to limit the amount of VOC levels in all materials, in particular solvent based adhesives. In California, for example, the South Coast Air Quality Management District (SCAQMD) has set regulations limiting the VOC levels of materials used to join thermoplastic materials. For example, pursuant to Rule 1168 of SCAQMD, the VOC limits for CPVC and/or polyvinyl chloride (PVC) solvent based adhesives, effective Jan. 1, 1994 were 450 grams/liter as measured by SCAQMD 316A. The VOC limits for acrylonitrile styrene butadiene (ABS) solvent based adhesives were 350 grams/liter as of Jan. 1, 1994 as measured by SCAQMD 316A. Further legislation has reduced these limits even further. Future proposed regulations, the SCAQMD VOC limits for CPVC and PVC solvent based adhesives will be 250 grams/liter whereas the SCAQMD VOC limits for ABS solvent based adhesives will remain at 350 grams/liter.
Several adhesives have been formulated which contain lower VOC levels than the conventional solvent based systems. The VOC levels of conventional solvent based adhesive systems was generally about 650 grams/liter as measured by SCAQMD 316A prior to 1994. For example, Australian Patent Application disclose a adhesive comprising more than 80 weight percent of n-methyl-2-pyrrolidone, more than 0.25 weight percent of a viscosity modifier and more than 10 weight percent of a vinyl based polymer. The viscosity modifier can be silica, a thickening agent or a thixotropic agent. Similarly, U.S. Pat. No. 4,675,354 discloses a glue solution which comprises a solution of a water insoluble synthetic organic polymer in a solvent such as N-methyl-2-pyrrolidone. This glue solution may be used at tropical temperatures without problems arising from solvent vapors and fire risks.
Also, U.S. Pat. No. 4,687,798 discloses a solvent cement used for joining water insoluble polymers. The solvent cement comprises about 10-15 weight percent of a water soluble polymer and a solvent. The solvent comprises ethyl acetate and N-methyl-2-pyrrolidone. The ethyl acetate ranges from about 3 percent to about 50 percent by weight of the solvent with the balance being N-methyl-2-pyrrolidone.
In addition, European Patent Application 0 547 593 A1 discloses a low VOC adhesive composition. The composition of this European Patent Application comprises a mixture of from 5 weight percent to about 60 weight percent of at least one water insoluble polymer, from about 1 weight percent to about 30 weight percent of inorganic or synthetic resinous hollow microspheres and from about 20 weight percent to about 70 weight percent of at least one volatile organic liquid which is a solvent for the water insoluble polymer.
U.S. Pat. No. 5,470,894 to Patel et.al., provides for an additional example of a low VOC solvent based adhesive. The low VOC solvent based adhesive in this patent is used to join CPVC pipes. The adhesive comprises a high vapor pressure solvent comprising from about 15 to about 35 weight percent of tetrahydrofuran and 0 to about 30 weight percent of methyl ethyl ketone; a low vapor pressure solvent comprising about 20 to about 45 weight percent cyclohexanone, 0 to about 30 weight percent of N-methyl pyrrolidone and from 0 to 10 weight percent of dibasic esters. Patel, et. al. state that the VOC level of their adhesive is at or below 450 grams/liter, while the adhesive meets or exceeds the required performance standards such as hydrostatic burst strength and hydrostatic sustained pressure tests.
Nonetheless, there is still an environmental concern with using any one of the above emunerated adhesives. There are however, alternatives to solvent based adhesives. These are mechanical, reactive, or thermal systems. Mechanical joining systems are generally very expensive to use. Examples of mechanical joining systems include Acorn Fittings from Hepworth Building Products; PolyGrip Fittings from Philmac Corporation and Uncopper Fittings from Genova. Thermal systems are unpredictable due to the difficulty in consistently producing adequate pipe/fitting unions. Examples of thermal systems include hot melt glues available from the Minnesota, Mining and Manufacturing Company. These thermal systems are difficult to apply and perform poorly. An example of a reactive system includes epoxy. Epoxy is available from the Noble Corporation under the tradename Copper Bond. Other examples of an epoxy include General Purpose Urethane, High Shear Strength Urethane and All Purpose Epoxy, all available from the Hardman Corporation. However, these reactive systems are problematic because they have long cure times, poor green strength. Their efficacy is also temperature dependent; at low temperatures epoxy materials have very long cure times. Furthermore, there may be by products of the chemical reactions which may be detrimental to the strength of the pipe. Even though these alternatives exist, they are cost prohibitive, time consuming and cumbersome.
Despite some of the air quality problems, there are benefits to continuing to use the solvent based adhesives to join thermoplastic materials. First, solvent based adhesives are easy to use and many workers have years of experience using these types of adhesive systems. Second, there are low production costs in making the solvent based adhesives as well as long term durability once the adhesives are used to join the two thermoplastic materials. Further, the solvent based adhesives can be used on location to join the two thermoplastic materials together without any additional equipment. Fourth, the solvent based adhesive system cures pretty rapidly, allowing for testing. In addition, one technique can be used to apply the solvent system for all sizes of pipe. Generally, the solvent based adhesive system can be applied to the joint at any temperature in the range of 0° to 120° F., if the solvent based adhesive system meets the Underwriter's Laboratories Test 1821. Also, the solvent based adhesive systems do not rely upon a chemical reaction for their efficacy. Moreover, the solvent based adhesive system can possibly be stored long term at ambient temperatures. Therefore, overall the solvent based adhesive systems are generally practical and economical.
Thus, there currently exists a need for a low VOC solvent based adhesive which volatilizes at substantially reduced rates as compared to conventional solvent based adhesives, has adequate shelf and storage life. Furthermore, there exists a need for a low VOC solvent based adhesive that meets the required performance criteria necessary to join two thermoplastic materials together. Additionally, there exists a need for a low VOC solvent based system with higher flash points than conventional solvent based adhesives and/or primers for adhesives.
SUMMARY OF THE INVENTION
The present invention comprises a novel low VOC solvent based adhesive comprising a mixture of two volatile organic solvents, and resin. Optionally, the novel low VOC solvent based adhesive may contain a thixotropic agent such as silica. Preferably, the novel low VOC solvent based adhesive comprises 5-20% thermoplastic resin; 38-65% of n-methyl-2-pyrrolidone; 20-45% dimethyl adipate and 1.5-2% of silica. Most preferably, this novel low VOC solvent based adhesive has a flash point above 100 ° F. as measured in accordance with ASTM D 3828-87.
In a further embodiment of the invention, the invention comprises a novel low VOC solvent based adhesive having a flash point substantially greater than 100° F. as measured by ASTM D 3828-87. Preferably, novel low VOC solvent based adhesive comprises 5-20% thermoplastic resin, 38-65% of n-methyl-2-pyrrolidone; 20-45% dimethyl adipate, 1.5-2% of silica and 5-10% of a ketone having a flash point greater than 100° F. Preferably, the ketone is either 5-methyl-2-hexanone or 4-methyl-2-pentanone.
The low VOC solvent based adhesive of the instant invention has a VOC level of less than 450 grams/liter as measured by SCAQMD 316A. Preferably, the novel low VOC solvent based adhesive has a VOC level of less than 250 grams/liter as measured by SCAQMD 316A.
DETAILED DESCRIPTION
The low VOC solvent based adhesives of the instant invention comprises a mixture of two volatile organic liquid solvents which are capable of vaporizing at ambient temperatures as well as a thermoplastic resin. Furthermore, the low VOC solvent based adhesives of the instant invention have a flash point greater than 100° F. as measured by ASTM D 3828-87. Other ingredients, including other solvents, fillers, thixotropic agents or stabilizers may be added to the low VOC solvent adhesive as desired. The low VOC solvent based adhesives as described herein in further detail generally have the following characteristics: viscosity from 500-3000 centipoise; a green strength of 1-2 minutes; less than 20% solids in the adhesive, an indefinite shelf life in nonreactive containers and a variable cure time. The cure time can be varied for different end-use needs by minor adjustments of the solvent ratios used.
The flash point of a material is used as one of the properties that is considered assessing the overall flammability of a material. One method to determine a flash point of a material is ASTM D 3828-87, which is incorporated herein in its entirety. Flash points are used in safety and shipping regulations such as CFR §173.120 and §173.150 to define both flammable and combustible materials. These regulations specify the types of packaging required for these materials. If a material has a higher flash point, the packaging and its shipping requirements may not be as stringent as those generally required for solvent cements and/or primers. The thermoplastic resins that can be used in the formulation of the low VOC solvent based adhesive of the instant invention include polyvinyl chloride, chlorinated polyvinyl chloride, ABS, polystyrene, and any other amorphous thermoplastic resins which are soluble in the mixture of the two volatile organic solvents. Generally, the resin used in the solvent based adhesive of the instant invention is the same as the resin used to form the thermoplastic materials to be joined. Preferably, the resin is either CPVC, PVC or ABS. The CPVC and/or PVC resin should have an inherent viscosity in the range of about 0.6 to about 0.96. Preferably, the chlorination levels for the CPVC resins should range from about 58 to about 72 weight percent. Preferably, the chlorination level for the PVC resin should be less than 57%. Examples of possible ABS resins to be used include the Cycolac ABS resins from GE Plastics and the Lustran ABS resins from Monsanto. Most preferably, the resin is CPVC. Generally, the CPVC resin used is CPVC resin as defined in Class 23477 of the ASTM D1784. However, the molecular weight of the CPVC resin should not be below 0.68 IV (inherent viscosity). Examples of suitable CPVC to be used in the instant invention include TempRite 674×571 CPVC, and TempRite 677×670 CPVC, all available from The B. F. Goodrich Company. (TempRite is a registered trademark of The B. F. Goodrich Company). The most preferred CPVC resin is TempRite 674×571, from The B.F. Goodrich Company. The amount of thermoplastic resin added to the low VOC solvent based adhesive ranges from about 5 to about 20 weight percent.
In addition to the thermoplastic resin, the low VOC solvent based adhesive of the instant invention includes a mixture of two volatile organic liquid solvents that are capable of vaporizing at ambient temperatures. The first organic solvent that is used in the mixture is a low vapor pressure solvent. N-methyl-2-pyrrolidone ("NMP") is the most preferred low vapor pressure solvent. NMP is commercially available from Aldrich Chemical, Ashland, BASF, Chemoxy International and Janssen Chemical. The first organic liquid solvent is generally found in the novel adhesive in the range of from 38 to about 65 weight percent. In the most preferred embodiment, 50 percent of NMP is present in the low VOC solvent based adhesive.
The second organic liquid solvent in the solvent based adhesive is chosen from the group consisting essentially of pimelic acid, monomethyl glutarate, monomethyl pimelate, monomethyl azelate, monomethyl sebacate, monoethyl adipate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl pimelate, dimethyl subrate, dimethyl azelate, glutaryl chloride, adipoyl chloride, and pimeloyl chloride, or mixtures thereof. For example, mixtures of dimethyl glutarate, dimethyl adipate and dimethyl succinate can be used. A commercially available example of such a mixture is DBE-9, available from DuPont Chemical. The second organic solvent is found in the range of about 20% to about 45% in the solvent mixture. The most preferred second organic solvent is dimethyl adipate ("DMA"). DMA is available from the DuPont Company under the tradename DBE-6. The DBE-6 is believed to be a mixture comprising 98.7% DMA, <0.5% dimethyl glutarate, and <0.1% dimethyl succinate. In the most preferred embodiment, 27% of the DMA is used in the low VOC solvent based adhesive mixture.
The low VOC solvent based adhesive also may include other optional ingredients. For example, the low VOC solvent based adhesive of the present invention may include minor amounts of other solvents which do not raise the VOC level of the adhesive above 450 grams/liter and which are miscible with the mixture if the two volatile liquid organic solvents. Examples of possible solvents which can be used include ketones, esters, halogenated solvents, ethers, and other liquids. Ketones which can be used in the instant invention as additional solvents include acetone, methyl ethyl ketone, methyl-iso-amyl ketone, methyl-iso-butyl ketone isophonene, cyclohexanone and other ketones. Examples of esters which can be used in the instant invention include methyl acetate, ethyl acetate, ethyl formate, ethyl proprionate, and butyl acetate. Halogenated solvents which can be used include methylene chloride, ethylene dichloride and trichloroethylene. Methyl cellulose is an example of a possible ether which can be added as an additional solvent. Other possible liquids which can be utilized as additional solvents include tetrahydrofuran and any other high vapor pressure solvent provided that the other criteria, including but not limited to green strength and desired flash points enumerated above are met. Generally, these other liquids are added to obtain faster cure times or volatilization.
Fillers which are known in the art and any other materials which can function as inert fillers can be used in the instant invention. Examples of fillers which can be used in the instant invention include hollow spheres (glass or ceramic), polymers, glass spheres, magnesium silicate, magnesium oxide, shell flour, alumina, talc, barium sulfate, calcium carbonate, and other fine powder. These fillers are generally added in the amount of about 0.05 to 20 weight percent to the composition. Fillers can be added to reduce the cost, maintain the viscosity or reduce the VOC slightly. Preferred fillers include polymers and calcium carbonate.
The low VOC solvent based adhesive also may include optionally thixotropic agents in the composition. Examples of possible thixotropic agents which can be used include fumed silica, precipitated silica, benotite, clay, ground quartz, mica, ethyl cellulose, hydrogenated castor oil, organic modified clay, other thickeners or viscosity adjustors. Preferred thixotropic agents include fumed silica. Generally, the amount of thixotropic agent used if used at all is in the range of about 1 to about 3% by weight.
Further, pigments, dyes, dispersions or colorants may be added to the low VOC solvent based adhesive. Examples of possible pigments which can be used include titanium dioxide, calcium carbonate or carbon black. The amount of pigment used is generally in the range of 0.05% to about 5.0% by weight.
The low VOC solvent based adhesive may include other additives. This includes any additives known to those in the art. Suitable additives include for example but not limited to various stabilizers, antioxidants, electrostatic dissipative agents, smoke retardants, moisture scavengers, and acid scavengers. Since several additives can be combined in countless variations, the total amount of additive can vary from application to application. Optimization of the particular additive composition is not within the scope of the present invention and can be determined easily by one of ordinary skill in the art. Generally from about 0.5% to about 1.0% by weight of additives are added to the low VOC solvent based adhesive.
The ingredients for the low VOC solvent based adhesive can be combined in any convenient manner. For example, all the ingredients can be mixed together uniformly by mixing means such as a mixer. Preferably, the two solvents are first mixed together. No special sequence or order is necessary. The thermoplastic resin and the thixotropic agent are then added to the solvent mixture; no special order is required. A stir mixer such as Grenier Mixer, Model 3002 with fast agitation is used to dissolve the solids in the solvent quickly. The mixer was set at 400-500 rpm for about 10-15 minutes. The mixture may then be placed on a slower moving roller mixer to evenly blend the composition. An example of a possible roll mixer which can be used is the Paul O. Abbe Ball Mill. The mixture was placed in this Ball Mill for one hour at 160 rpm.
The low VOC solvent based adhesive can be applied by any method of application to the two objects made from thermoplastic materials that are going to be joined. Although not necessarily, prior to the application of the low VOC solvent based adhesive of this invention, the surfaces of the objects to be joined are lightly wiped with a brush or cloth containing acetone near the point of the desired joint. The low VOC solvent based adhesive can be applied by any method known in the art. Preferably, the low VOC solvent based adhesive is applied by a dauber to the two surfaces of the objects made from the thermoplastic materials, near the area of the desired joint. A uniform layer of adhesive is placed upon the two surfaces. Generally, a layer of approximately 1/2 to 1 mil thickness is placed upon the two surfaces. The joint can then be tested.
There are many uses of the low VOC solvent based adhesives of the instant invention. For example, the low VOC solvent based adhesive can be used to join thermoplastic pipe and fittings in various applications such as plumbing systems, cold and hot water distribution systems, sprinkler systems, spas, fire sprinkler systems, drain, waste and vent applications. The low VOC solvent based adhesive is useful for any other thermoplastic materials that can be joined. The following non-limiting examples serve to further illustrate the present invention in greater detail.
EXAMPLES
In the following examples, the novel low VOC solvent based adhesive of the instant invention was formulated. Generally, as a first step, a desired level for the VOC solvent based adhesive was determined. The desired VOC level is determined by the selection of the two solvents. Using SCAQMD 316A, the VOC constant for each of the solvents to be used in the low VOC solvent based adhesive was determined experimentally. The estimated VOC for the solvent based adhesive can then determine using the following equation: (VOC constant of solvent 1×% of solvent 1 based upon total amount of solvents in the adhesive)+(VOC constant of solvent 2×% of solvent 2 in adhesive based upon total amount of solvents)=estimated VOC level of the adhesive. Once this desired VOC constant was determined, the novel low VOC solvent based adhesive was formulated and the VOC level verified using SCAQMD 316A. The viscosity of the solvent cement was optimized via the addition of thixotropic agents. The green strength and the cure time were varied by adjustments of the solvent ratios while still maintaining a desired VOC level and viscosity.
The cure time may be varied to adjust for end-use needs. In the examples, the amount of the NMP and DMA was varied. The following examples were all tested for the VOC level, the cure time, the green strength and quick burst. The VOC level is measured using the test in SCAQMD 316A; the quick burst is measured using ASTM 1599 and the cure time is measured using Underwriters Laboratories UL 1821.
The green strength is tested by a procedure whereby the tester tries to pull or twist apart the bonded pipe and fitting. In carrying out the procedure, the inner part of the thermoplastic fitting and the outer part of the thermoplastic pipe (which fits in the fitting) are each coated with the same adhesive. At the end of one minute, the tester tries to pull or twist apart the two pieces. Generally, the bonded pipe and fitting are subjected to 6 foot-lbs. of torque during the test. If the two pieces do not come apart, this constitutes a "yes" which means that the experiment is repeated until a "no" is obtained. Each time the experiment is redone, one additional minute is added to the previous time. The time that a "no" is reached, indicates the green strength. The formulations as well as the results are set forth in Table 1.
Examples of commercial solvent cements with which the instant invention is compared and contrasted with include Orange Lo V.O.C. Medium Booked CPVC Cement (one step) and two steps cements available from Oatey; as well as the Weld-On CPVC 2714™ Orange Heavy Booked Cement (one step) and two step cements from IPS. Generally, the one step commercial solvent cements have a VOC level of about 450 grams/liter, whereas the two step cements have a VOC level greater than 650 grams/liter.
TABLE 1__________________________________________________________________________ TempRite Green Quick DMA/ 674 × 571 VOC Strength Viscosity Burst NMPEx. DMA NMP Silica CPVC (g/l) (min) (cp) (psi) Ratio__________________________________________________________________________1 20 65 2 13 154 2 1445 >1400 0.312 30 55 2 13 143 1 2585 >1400 0.553 40 45 2 13 164 1 9285 >1400 0.894 45 40 2 13 128 1 69950 >1400 1.125COMMERCIAL SOLVENT CEMENTS >400 1-2 500-3000 PIPE or >1400 FAILURE__________________________________________________________________________
Examples 1 through 4 in Table 1 illustrate that solvent based adhesive formulations having DMA/NMP ratio of from 0.31 to 1.125 have a lower VOC than standard solvent cement formulations. Examples 3 and 4 would be unacceptable for commercial use due to the high viscosity although still effective adhesive.
TABLE 2__________________________________________________________________________ TempRite 674 × Cyclo- Green 571 hexa- DMA/N Strength Viscosity Quick BurstEX. DMA NMP Silica CPVC none MEK THF EA MEOH VOC(g/l) MP Ratio (min.) (cp) (psi)__________________________________________________________________________5 20 60 1 13 6 278 0.33 2 1940 >14006 20 60 1 13 6 274 0.33 2 1672 785 PF7 26 55 1 13 5 267 0.47 3 1872 825 PF8 25 55 1 13 2 2 2 261 0.45 2 2136 850 PF9 26 55 1 13 5 268 0.47 1 1485 >140010 26 55 1 13 5 239 0.47 2 1130 >140011 30 50 2 13 5 250 0.60 2 2990 743 PF12 30 50 2 13 5 278 0.60 2 2992 938 PF13 30 50 2 13 5 283 0.60 1 2830 >140014 30 50 2 13 5 250 0.60 2 2810 >140015 45 35 2 13 5 293 1.29 3 54000 938 PF16 45 35 2 13 5 257 1.29 2 11140 900 PF17 45 35 2 13 5 232 1.29 3 10020 935 PF18 45 35 2 13 5 253 1.29 12 78700 >1700 PF19 20 60 1 13 6 363 0.33 2 604 >140020 20 60 1 13 6 321 0.33 2 580 1650 PF21 20 60 1 13 6 362 0.33 1 245 1625 PF22 20 60 1 13 6 341 0.33 1 300 >140023 25 50 1 15 9 355 0.50 2 1112 1800 PF24 25 50 1 14 9 281 0.50 2 1468 675 PFCOMMERCIAL SOLVENT CEMENTS >400 1-2 500- >1400 PSI 3000 OR PIPE FAILURE__________________________________________________________________________
Examples 5 through 24 in Table 2 illustrate that solvent based adhesives having a DMA/NMP ratio of from 0.3 to 1.3 and having either a third minor solvent or combination of solvents which provide a minor portion (<10%) of the overall formulation will have a VOC level lower than 400 grams/liter and perform as well as existing commercial solvent based adhesive systems having a VOC level of 450 grams/liter or greater.
In these examples, the VOC levels are all below 300 g/l and the bond strength passes all enumerated criteria. Formulations 15, 16, 17, and 18 all would be commercially unacceptable due to the high viscosity, although still effective as an adhesive.
TABLE 3__________________________________________________________________________ TempRite TempRite DMA/ 677 × 670 674 × 571 Cyclo- Green Quick Viscosity NMPEx. DMA NMP Silica CPVC CPVC hexan-one MEK THF EA VOC(g/l) Strength Burst(psi) (cp) Ratio__________________________________________________________________________25 20 60 1 13 6 363 2 >1400 604 0.3326 20 60 1 13 6 308 2 >1400 1904 0.3327 20 60 1 13 6 321 2 1650 PF 580 0.3328 20 60 1 13 6 274 2 785 PF 1672 0.3329 20 60 1 13 6 362 1 1625 PF 245 0.3330 20 60 1 13 6 314 1 >1400 PF 885 0.3331 20 60 1 13 6 341 1 >1400 PF 300 0.3332 20 60 1 13 6 337 1 >1400 PF 975 033COMMERCIAL SOLVENT CEMENTS >400 1-2 >1400 PSI 500- OR PIPE 3000 FAILURE__________________________________________________________________________
Examples 25 through 32 in Table 3 illustrate that low VOC solvent based adhesives having a DMA/NMP ratio of 0.3 and having a third minor solvent comprising <10% of the overall formulation will have a lower VOC level and the formulation will perform as well as existing commercial solvent based adhesives. Furthermore, if a lower molecular weight CPVC resin is used in the formulation, the viscosity can be improved and the adhesive can perform better than existing solvent based adhesives.
TABLE 4__________________________________________________________________________ TempRite Quick DMA/ 674 × 571 VOC Viscosity Burst NMPEx. CPVC Silica NMP MEK DMA (g/l) (cp) (psi) Ratio__________________________________________________________________________33 12 2 41 10 35 287 1460 >1400 PF 0.8634 11.5 1.5 43 10 34 213 1200 >1400 PF 0.835 11.5 1.5 39 10 38 289 1325 >1400 PF 0.9736 11.5 1.5 47 10 30 271 810 >1400 PF 0.6437 13.5 1.5 43 10 32 274 1975 >1400 PF 0.7438 13.5 1.5 50 8 27 201 1840 >1400 PF 0.5439 13.5 1.5 48 8 29 243 1890 >1400 PF 0.640 10 2 44 10 34 252 610 >1400 PF 0.7741 12.5 1.5 40 10 36 269 1950 >1400 PF 0.942 12.5 1.5 41 8 37 244 3305 >1400 PF 0.943 13.5 1.5 41 10 34 242 4210 >1400 PF 0.82__________________________________________________________________________
Examples 33 through 43 illustrate that solvent based adhesives having a DMA/NMP ratio from 0.54 to 0.97 and having MEK (2 Butanone) as a minor component at a level less than 10% of the overall formulation will have a lower VOC level than commercial solvent based adhesives (with a VOC level of 450 grams/liter or greater) and will perform as well as these commercial solvent based adhesives.
Furthermore, Example 38 illustrates that a solvent based adhesive having a DMA/NMP ratio less than 0.55 and having MEK (2 Butanone) as a minor component at a level less than 8% of the overall formulation will have a VOC level of 201 grams/liter and will perform as well as conventional solvent based adhesives.
In the next example, Example 44, the following components were used:
50% NMP
30% DBE-6 (DMA)
5% butanone (MEK)
13% TempRite 674×571 CPVC Resin
2% Silica
PROPERTIES
______________________________________ VOC on Various Quick Burst onSubstrates Substrates VariousJoined (g/l) Substrates (psi)______________________________________CPVC 250 938-pipe failurePVC 168 1575-pipe failureABS 169 375-pipe failure______________________________________
The VOC level of the solvent based adhesive system was measured using SCAQMD 316A; the quick burst was measured using ASTM D-1599. The following properties were obtained:
Sustained Long Term Hydrostatic Pressure at Elevated Temperature (150° F., 370 psi pipe pressure, 1000 hours minimum time)--ASTM D-2837
1" assembly 1158 hours with no failure
3" assembly 1315 hours with no failure
Viscosity (Brookfield): 2792 cps (Brookfield Viscometer Spindle 5 at 100 rpm)
Green Strength: 2 min.
Lap Shear: 148 psi--UL 1821
______________________________________Cure Times:______________________________________at 73° F. 7 min.at 28° F. 20 min.at 0° F. (with acetone cleaning) 45 min.______________________________________
Stress Crack Tendency
after 20 hours dulling of the plaque noted
after 202 hours swelling at the edges of the plaque noted.
Test discontinued.
The stress cracking tendency of the samples referred to above is measured in the following manner. Samples having a dimension of 7 cm×3 mm×1.25 cm are prepared from compression molded plaques. These samples are inserted into a test fixture as described in FIG. 1 of the article "Stress Cracking Of Rigid Polyvinyl Chloride By Plasticizer Migration", Journal of Vinyl Technology, December 1984, Vol. 6, No. 4. The samples are inserted into the fixture by use of a benchtop vise. The sample is placed at the edge of the vise with approximately half of its width extending beyond the edges of the vise. The vise is then used to bend the sample until its ends are close enough to slide it into the edge of the test fixture. After the sample is positioned into the test fixture, the low VOC solvent based adhesive is applied to the sample using a medicine dropper. The sample is removed periodically from the chemical to check for signs of cracking, crazing or discoloration. Testing is carried out until failure is observed.
In the following examples, the first organic liquid solvent in the examples was NMP. The second organic liquid solvent was chosen from the group consisting essentially of pimelic acid, monomethyl glutarate, monomethyl pimelate, monomethyl azelate, monomethyl sebacate, monoethyl adipate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl pimelate, dimethyl subrate, dimethyl azelate, glutaryl chloride, adipoyl chloride, and pimeloyl chloride, or mixtures thereof. The VOC level, the green strength and the quick burst were measured for each combination, as set forth in Table 5.
TABLE 5__________________________________________________________________________ TempRite 674 × 571 Green Quick CPVC Strength BurstComponent Amount M-pyrol Silica Resin VOC(g/l) (min) (psi)__________________________________________________________________________Pimelic 19.5 72.9 1.4 6.2 283 1 1375 FAcidMono- 27 62 2 9 253 I 1200 FmethylglutarateMono- 25 65.6 1.9 7.5 158 1 1150 FmethylpimelateMono- 40 45 3 12 121 3 >1400 gelmethylazelateMono- 40 45 3 12 137 3 >1400 gelmethylsebacateMono- 30.8 57.7 2.3 9.2 179 3 1000 FethyladipateDimethyl 40 45 3 12 341succinateDimethyl 40 45 3 12 289glutarateDimethyl 40 45 3 12 152adipateDimethyl 40 62 2 9 241 1 1450 FpimelateDimethyl 40 45 3 12 77 2 >1400suberateDimethyl 40 45 3 12 114 2 >1400azelateGlutrayl 27 62 2 9 197 1 1175 PChlorideAdipoyl 27.6 62.1 2.1 8.3 83 2 1400 FChloridePimeloyl 27 62 2 9 178 2 1100 FChloride__________________________________________________________________________
The data in this Table 5 shows that when the NMP is used in combination with one of the enumerated second organic liquid solvents, an adhesive composition is obtained with adequate properties.
The three Examples set forth below deal with the measurement of the flash point of the novel low VOC solvent based adhesive of the instant invention. The flash point of the compositions was measured on the Erdco Rapid Tester, Model RT-1, in accordance with ASTM D 3828-87. The following results were obtained.
Composition A
13.5% TempRite 674×571 CPVC Resin
1.5% Silica
27% DMA
58% NMP
Flash Point: 203° F.
VOC level of 153 g/l as measured by SCASQMD 316A
Composition B
13.5% TempRite 674×571 CPVC Resin
1.5% Silica
27% DMA
50% NMP
8.0% 5-methyl-2-hexanone (CAS #110-12-3) available from the Aldrich Chemical Co.
Flash Point: 167° F.
VOC level of 240 g/l as measured by SCAQMD 316A
Composition C
13.5% TempRite 674×571 CPVC Resin
1.5% Silica
27% DMA
50% NMP
8% 4-methyl-2-pentanone (CAS #108-10-1) available from the Aldrich Chemical Co.
FlashPoint: 131° F.
VOC level of 215 g/l as measured by SCAQMD 316A
In contradistinction, the flash points of the following commercial one step and two step solvent cements was obtained:
Standard Oatey One Step "Low VOC" Solvent Cement: Fp: -20° C. or -4° F.
Standard Oatey Two Step Solvent Cement: Fp: -15° C. or +5° F.
Neat Tetrahydrof iran: -17° C. or 1° F.
Neat Cyclohexanone: 67° C. or 154° F.
Neat MEK (2-butanone): -3° C. or 26° F.
In summary, a novel and unobvious low VOC solvent based adhesive has been as well as the process of applying such low VOC solvent based adhesive to two thermoplastic materials that are going to be joined together and having a flash point over 100° F. as measured by ASTM D3828-87. Although specific embodiments and examples have been disclosed herein, it should be borne in mind that these have been provided by way of explanation and illustration and the present invention is not limited thereby. Certainly modifications which are within the ordinary skill in the art are considered to lie within the scope of this invention as defined by the following claims.
|
The present invention relates to a low VOC solvent based adhesive comprising a mixture of at least two organic solvents and a thermoplastic resin having a flash point of at least 100° F. when measured in accordance with ASTM D3828-87. The low VOC solvent based adhesive of the instant invention volatilizes at substantially reduced rates as compared to conventional solvent based adhesives. Furthermore, this novel low VOC solvent based adhesive is easy to apply, cost effective, cures within a reasonable time without the use of heat, ultraviolet light or other mechanical devices. In addition, the novel low VOC solvent based adhesive can be stored in containers other than the steel tins.
| 2
|
FIELD OF INVENTION
The present invention relates to rock drill bits primarily used in rock boring for blast holes, water and oil wells and the like.
BACKGROUND OF THE INVENTION
Recent advances in carbide insert and rock drill bit design have increased the life of gage buttons (for example by the use of longer length buttons, double gage row, shot peened holes, etc.) to the point where face buttons become the predominate mode of failure. Often severe wash on the face removes adequate support of the button, and eventually the carbide button support will be weakened to the point of permitting button failure or simply loss of the button.
BRIEF SUMMARY OF THE INVENTION
The present invention teaches the distribution of carbide cutter inserts such as carbide buttons in a radial line outward from the exhaust hole. This prevents the free flow of exhaust wash which carries abrasive rock particles about the base metal surrounding the carbides.
The object of the invention therefor, is to prevent an unrestricted wash path to the carbide inserts.
A further object of the invention is to establish preferred wash paths which do not approximate carbide button locations.
Yet a further object is to provide an extended life carbide cutter bit which is economical to manufacture.
These and other objects are obtained in a carbide button bit comprising:
a body having a longitudinal axis extending parallel to the direction of drilling;
a face disposed on the body towards the front or leading edge of the body and perpendicular to the longitudinal axis of the body;
the face accessing a source of pressure fluid at a source point on the face; and
a plurality of cutting means for effecting rock cutting disposed on the face in a manner such that the cutting means are disposed in a pattern extending along lines of radial extension form the source point.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the plan view of an eroded carbide button bit according to the prior art.
FIG. 2 shows the plan view of a carbide button bit according to the present invention.
FIG. 3 shows the elevation view of a carbide button bit according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to the prior art embodiment shown in FIG. 1. A typical erosion pattern is shown by the shaded areas of the bit face. The present invention minimizes the erosion of the bit face by placing the carbide button in radial alignment on the face of the bit about the relieved exhaust port. This promotes flow between the buttons rather than by the button by providing a free flow path on the one hand and a multiplicity of flow restrictions where possible in the other.
Referring specifically to FIG. 2, a drill bit body in general is shown and referred to by reference numeral 100.
The body has a longitudinal axis parallel to direction of drilling 20 and a lead edge containing a face portion and a beveled or sloped portion. Concentric about the axis is a gauge portion which forms the periphery and a shank portion which extends rearward form the leading edge to connect with a drill (not shown).
The face of the bit is referred to by reference numeral 1, the gauage of the bit is referred to by reference numeral 2, and a sloped portion of the bit connecting the face and gauge as numeral 3. As can be seen in FIG. 2, face buttons are identified by reference numeral 4, gauge buttons as 5 and intermediate buttons as 6. The exhaust port 7 is shown predominately entering the intermediate sloping portion 3 with a relief channel 8 and a directional flow channel 11 extending towards and on the face 1. The directed flow channel 11 promotes directed flow of exhaust fluid across the face of the bit in a manner indicated by the flow arrows 12.
The gauge 2 of the cutter bit is further provided with a series of seven (7) peripheral relief cuts 9 which facilitate the flow of exhaust fluid and/or drilling mud from the exhaust port to behind the bit towards the drill string to eventually exit the drill hole along the drill string (not shown) in a manner conventional to down hole drilling.
The location of the buttons or carbide cutter bit inserts according to this invention are in radial alignment extending from the exhaust port. Dotted lines 10 show the radial lines of extension. Exhaust fluid can thereby pass unimpeded between the rows of buttons while at the same time the carbide buttons impede the flow to a maximum extent by being in line. The effect of this is to reduce the erosion of base metal in the area of the buttons thereby preserving their mounting integrity and life.
Referring to FIG. 3, the elevation view of the cutter bit is shown. As can be seen, the bit is further provided with a shank portion 11 for mating with the drill (not shown). The drill bit attached to the drill is rotated and/or receives a percussive blow to grind and/or crush the rock below the bit. The small pieces thus formed are washed from the hole by means of pressure fluid such as air, drilling mud or water in a conventional manner well-known to the drilling art.
Having described my invention in detail, numerous variations of the specific layout of buttons will occur to those skilled in the art and I do not wish to be limited in the scope of my invention except as claimed.
|
Disclosed herein is an erosion resistant down hole rock drill bit which utilizes a radial distribution of carbide cutter bits or buttons about the exhaust hole. This minimizes carbide wash or removal of base metal which retains the carbide and thereby extends bit life.
| 4
|
BACKGROUND OF THE INVENTION
The present invention relates generally to a lock mechanism of the type designed to prevent a gliding or hinged door or window from being opened. More particularly, the invention relates to such a mechanism which employs a two piece cam gear/cam rack assembly which both actuates the lock and prevents it from being backdriven.
U.S. patent application Ser. No. 689,296, filed on Apr. 22, 1991 (now U.S. Pat. No. 5,092,640, issued Mar. 3, 1992) and assigned to the same assignee as the present invention, discloses a latch mechanism which is particularly useful in combination with the lock mechanism of the present invention. To the extent that the disclosure of Ser. No. 689,296 is necessary for the understanding of the present invention, that application is herein incorporated by reference.
Various devices are known for locking a gliding or hinged door or window. A common and simple version of such a device has a housing attached to the window frame and a bolt slidably mounted within the housing. A keeper attached to the window sash is positioned to receive the bolt when the window is closed. Thus, the bolt can be moved from a retracted position, where the window can be opened, to a forward position, where the bolt engages the keeper and prevents the window from being opened.
In order to increase the force applied to the bolt so as to make it easier to move the bolt, it is known to provide a rotating actuator for the bolt. The actuator is rotatably mounted on the lock housing, and has at least one arm projecting therefrom. When the actuator is rotated, the arm engages the bolt, causing the bolt to slide into engagement with the keeper. An example of such a window lock is shown in U.S. Pat. No. 800,043 issued to White.
For security purposes, it is important when designing such a window or door lock that the lock cannot be back-driven. In other words, when the bolt is in the engaged position, it should not be able to be forced back into the retracted position by pressure against the bolt. One known lock mechanism which is designed so that it cannot be back-driven is shown in FIG. 1.
As shown in FIG. 1, the lock mechanism has a housing 80 which is designed to attach to one panel of a door or window (not shown). A base member 82 is slidably mounted within the housing. A bolt (not shown) is attached to the base member and positioned to engage a keeper (not shown) located on the door or window frame. An actuator 83 is rotatably mounted on the housing. The actuator is hingedly connected to the base member via arm 84 and link 85.
Rotation of the actuator in the clockwise direction causes the base member (and the bolt attached thereto) to slide linearly into the locked position. In this position, the linkage formed by arm 84 and link 85 is positioned over-center. By this arrangement, the lock mechanism cannot be back-driven, because any attempt to force the base member toward the unlocked position merely causes arm 84 to press harder against stop surface 86.
This lock suffers from several drawbacks. One, the linkage between the actuator and bolt is expensive to manufacture and assemble. The linkage also increases the size of the lock, because room must be provided for both the actuator arm and the link, and because enough space must be provided to allow the linkage to move over-center.
SUMMARY OF THE INVENTION
The present invention is a lock intended primarily for gliding or hinged doors or windows. The lock is an improvement over the prior art in that it is a very simple mechanism which nonetheless is secure and cannot be back-driven. The lock mechanism is made up of essentially two parts: a cam gear which is rotatably mounted on a housing and acts as an actuator, and a cam rack which is linearly slidable relative to the housing. A bolt is attached to the cam rack. The cam gear has a center gear tooth and at least one lateral gear tooth extending from a central hub. The cam rack has a centrally disposed engagement portion which is designed to receive the center gear tooth of the cam gear. The cam rack further has at least one lateral cam surface and lateral stop surface located adjacent thereto.
In use, the primary force for moving the cam rack is provided by the force of the center gear tooth against the engagement portion during rotation of the cam gear. However, when the cam gear has been rotated a predetermined amount, the lateral gear tooth comes into contact with the lateral cam surface located on the cam rack. The action of the lateral gear tooth against the lateral cam surface upon further rotation of the cam gear not only increases the force applied to move the cam rack, but also disengages the center gear tooth from the engagement portion. Once in the locked position, the lateral gear tooth engages the lateral stop surface, so as to prevent the cam rack, and hence the bolt attached to it, from being back-driven.
Preferably, the cam gear has two lateral gear teeth, one located on either side of the center gear tooth, and the cam rack has two sets of lateral cam surfaces and stop surfaces, each set being located generally on opposite sides of the central engagement portion. Such an arrangement allows for the lock to be bi-directional; i.e., from a central, unlocked position, the cam gear can be rotated either clockwise or counterclockwise so as to move the cam rack either direction into a locked position. Further, the cam gear and cam rack are dimensioned such that whichever direction the cam gear is rotated, when one of the lateral cam teeth engages a lateral stop surface so as to lock the cam rack in place, the other lateral cam tooth engages a side wall of the central engagement portion so as to prevent further rotation of the cam gear.
The preferred angle between the two lateral cam teeth is 90 degrees, so that the cam gear need only be rotated 45 degrees to move the cam rack from the central, unlocked position to either one of the locked positions. A handle is preferable provided which can releasably engage the hub of the cam gear in order to provide additional torque for rotating the cam gear.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a prior art locking mechanism;
FIG. 2 is a perspective view of a portion of a gliding glass door o window upon which a latching and locking assembly made according to the preferred embodiment of the present/invention is mounted;
FIG. 3 is a perspective view of the assembly of FIG. 2, showing the latching mechanism in the unlatched position;
FIG. 4 is a perspective view of the assembly of FIG. 2, partially exploded, showing the locking mechanism in the unlocked position;
FIG. 5 is a cross-sectional view taken along lines 5--5 of FIG. 4;
FIG. 6 is a cross-sectional view similar to FIG. 5, taken upon partial movement of the locking mechanism toward the locked portion; and
FIG. 7 is a cross-sectional view similar to FIG. 5, showing the locking mechanism is the locked position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The lock mechanism of the present invention is shown in FIG. 2-7 as being integrally formed with a latch mechanism of the type disclosed in U.S. application Ser. No. 689,296, which has been incorporated by reference. However, it is to be understood that the lock mechanism of the present invention need not be limited for use with the latch assembly shown in the preferred embodiment. It can be used by itself, or with some other type of latch mechanism.
FIG. 2 shows a portion of a typical gliding glass door or window 1 upon which the latching and locking assembly of the preferred embodiment is mounted. Such gliding doors and windows are well-known in the art. They are generally made up of first and second panels 2 and 3. Each panel has two vertical sash members 11, a horizontal lower sash member 15, and a horizontal upper sash member (not shown) which together hold glass G in place. The panels are mounted within a frame consisting of vertical frame members 5, a horizontal lower frame member 9 and a horizontal upper frame member (not shown). A track 4 extending along the lower frame member 9 allows the panels 2 and 3 to slide so as to open or shut the window or door.
The locking and latching assembly of the preferred embodiment is designated as 20 in FIG. 2, and is attached to panel 3. A latch keeper 22 is mounted on panel 2. A lock keeper 25 is mounted on the lower frame member 9. As will be discussed in further detail, assembly 20 has a latch mechanism to engage the latch keeper 22 and thereby hold panels 2 and 3 together. The assembly further has a lock mechanism which engages the lock keeper 25 to hold the panels relative to the window frame.
The latch mechanism of assembly 20 can be seen clearly in FIG. 3. This latch mechanism generally includes a latch member 26 and a half cylinder member 28 disposed within a housing 30. Half cylinder member 28 is slidable (vertically in FIG. 3) linearly within the housing and is made up of a half cylinder 31 integrally formed with a planar base member 32 (FIG. 4). A spiral ridge 33 extends around the outer surface of half cylinder 31. A corresponding spiral groove 35 located in latch member 26 engages the spiral ridge on the half cylinder. As described in greater detail in U.S. Ser. No. 689,296, in accordance with this design, vertical movement of half cylinder member 28 causes the latch member to rotate about a vertical axis. The latch member is thus rotatable between a position of engagement with latch keeper 22, wherein the window panels are latched together, and a free position wherein the panels are free to be opened.
The locking mechanism which constitutes the present invention is shown in FIG. 4. As seen therein, a cam rack 37 is mounted within a recess formed in the planar base member 32. Two posts 38 projecting from the recessed portion of base member 32 engage two openings 40 in the cam rack to aid in holding the base member and the cam rack together.
Cam rack 37 is made of a front wall 39, back wall 41, and side walls 43 and 45 so as to define an open space within the cam rack. An engagement portion 48 extends between the front and back walls within the cam rack. As shown in FIG. 5, the engagement portion has two generally planar outer wall surfaces 48a, and a centrally-located U-shaped channel 53. Side walls 43 and 45 each define an angled cam surface 43a and 45a, and a stop surface 43b and 45b. The stop surfaces extend generally parallel to the outer wall surfaces 48a.
Cam rack 37 has a projection 54 located on one side of thereof. A bolt 56 has an opening which engages projection 54 so as to connect the cam rack and the bolt together. The bolt is positioned to selectively engage lock keeper 25 as will be hereinafter explained.
Partially located within the cam rack is a cam gear 42. Cam gear 42 has a short central gear tooth 58 and two longer lateral gear teeth 59 and 60. The angle between gear teeth 59 and 60 is preferably about 90 degrees, with a central gear tooth being located half way between the two lateral gear teeth. Cam gear 42 also has a cylindrical projecting pin 44. This pin engages an opening located in the housing so that the cam gear can rotate about axis 49. A hexagonal shaft 50 having a slot 51 extending therealong is also located on the cam gear. A removable handle 52 with a similar hexagon-shaped engagement portion is designed to engage shaft 50 so as to provide extra torque for rotation of the cam gear. As will be described in more detail with respect to FIGS. 5-7, the cam gear engages the cam rack so that upon rotation of the cam gear, the cam rack, as well as the planar base member and the bolt, are moved linearly.
The cam gear and cam rack are shown in the unlocked position in FIG. 5. Central gear tooth 58 of the cam gear is located within channel 53 of the engagement portion, while lateral gear teeth 59 and 60 are located within the cam rack on either side of the engagement portion. As the cam gear is rotated clockwise, central gear tooth 58 engages the engagement portion so as to move the cam rack (as well as base member 32 and bolt 56) linearly in the direction of arrow 62.
This motion continues until lateral gear tooth 59 contacts cam surface 43a, as shown in FIG. 6. The interaction between gear tooth 59 and cam surface 43a upon further rotation of the cam gear has two results. One, the force of gear tooth 59 against the cam surface adds to the lateral force applied by the cam gear against the cam rack. This aids movement of the cam rack toward the locked position. Two, as the rack moves to the locked position, central gear tooth 58 is lifted out of engagement with the engagement portion.
The cam gear and rack are shown in the locked position is FIG. 7. In this position, bolt 56 has engaged with the lock keeper 25 so as to lock the gliding door or window panel relative to the frame member 9. In the locked position, gear tooth 60 of the cam gear contacts the outer wall surface 48a of the engagement portion to prevent further rotation of the cam gear in the clockwise direction. Further, the end of gear tooth 59 engages stop surface 43b so as to prevent the cam rack from being back-driven. Particularly, force applied against the cam rack in the direction opposite to that of arrow 62, for example when an unauthorized person attempts to force bolt 56 out of engagement with keeper 25, causes the stop surface 43b to press harder against gear tooth 59. Since the cam gear cannot move linearly with respect to the housing, such force will not cause backward movement of the rack.
To disengage the lock mechanism, the cam gear is merely rotated from the position of FIG. 7 to that of FIG. 5. Such rotation causes gear tooth 59 to disengage from stop surface 43b and reengage cam surface 43a. Upon further rotation in the counter clockwise direction, first the cooperation of gear tooth 59 and cam surface 43, and then the cooperation of central gear tooth 58 and engagement portion 48, causes the cam rack to move linearly in the direction opposition to arrow 62.
The lock mechanism of the present invention is bi-directional. That is, the cam gear can also be rotated counter clockwise from the unlocked position of FIG. 6, and the cam gear will move to a locked position, this time with gear tooth 60 engaging cam surface 45a and stop surface 45b.
Furthermore, because the cam rack is connected to planar base member 32, rotation of the cam gear also causes latch member 26 of the latching assembly to move in and out of the latched position. Thus, according to the preferred embodiment, the locking and latching functions are performed simultaneously simply by rotating the cam gear.
In the preferred embodiment, the cam gear, cam rack, and bolt are all made of sturdy metal material like steel, while the housing, handle and keeper can be contructed of plastic materials such as acetal or reinforced nylon. Other suitable materials can be used.
While the invention has been described with reference to the preferred embodiment, it must be understood that various changes and modifications are possible without departing from the spirit and scope of the invention. In particular, the locking mechanism of the present invention has been shown together with a separate latching mechanism. Such is not necessary. All that is required is that the cam rack be somehow mounted so as to be slidable linearly within the housing. Also, the lock keeper need not be attached to the frame, but can be attached to the other door or window panel. Furthermore, the shape, size, and arrangement of the various parts can be changed. Thus, the scope of the patent should be defined not with reference to the preferred embodiment, but to the following claims.
|
A lock intended primarily for gliding or hinged doors or windows. The lock is an improvement over the prior art in that it is a very simple mechanism which nonetheless is secure and cannot be back-driven. The lock mechanism is made up of essentially two parts: a cam gear which is rotatably mounted on a housing and acts as an actuator, and a cam rack which is linearly slidable relative to the housing. Rotation of the cam gear causes the cam rack to move between an unlocked and a locked position. Once in the locked position, a gear tooth of the cam gear engages with a stop surface on the cam rack to prevent the cam rack from being back-driven.
| 4
|
FIELD OF THE INVENTION
The present invention generally relates to a high temperature epoxy tooling composition for cast-to-size tools used in injection molding and sheet molding compound (SMC) molding of plastic materials, more particularly, it is concerned with a tough, high temperature epoxy tooling composition for making cast-to-size tools for use in injection molding and SMC molding at mold temperatures up to 200° C.
BACKGROUND OF THE INVENTION
Injection molding tools and SMC molding tools traditionally have been made of high strength tool steel because of its rigidity and durability. In the automotive industry, molds made of tool steel have been used to injection or compression mold automobile parts made of either thermoplastic or thermoset plastic materials. However, these steel molds are very costly due to the extensive machining required to make them.
It is a common practice in the automotive industry that before a new car is put into production, a limited number of concept or prototype cars are first built for testing. Designing forming tools with tool steel for molding plastic parts used in these prototype cars would not be practical for several reasons. First, a prototype car has to be built in a relatively short time which prohibits the use of tool steel for forming tools due to the extensive machining required. Secondly, the design of a prototype car is changed many times from the original design before it reaches a final production model. This means that many forming tools will have to be built before the design of a specific part is finalized. This makes the building of a steel forming tool prohibitive for cost reasons.
To remedy these problems, castable polymeric materials have been used to make prototype sheet metal stamping tools in recent years. One of these materials is epoxy. For instance, U.S. Pat. No. 4,423,094 to Dearlove et al and assigned to General Motors Corporation discloses a tough, durable epoxy novolac material for use in making sheet metal stamping dies. While this material exhibits good mechanical strength for tooling purposes, it can be used at mold temperatures of up to 150° C. only. This limits its use to sheet metal stamping tools. In most injection molding and SMC molding tools, the tooling material for the mold should remain stable at temperatures higher than 150° C. Another drawback of the Dearlove et al epoxy tooling composition is the high cost of the epoxy novolac resin.
It is therefore an object of the present invention to provide an epoxy tooling composition that can be used in injection molding or SMC molding tools at mold temperatures higher than 150° C.
It is another object of the present invention to provide an epoxy tooling composition that can be used in a cast-to-size injection molding or SMC molding tool at mold temperatures higher than 150° C.
It is yet another object of the present invention to provide an epoxy tooling composition of high compressive strength that can be used in a cast-to-size injection molding or SMC molding tool at mold temperatures higher than 150° C.
SUMMARY OF THE INVENTION
In accordance with a preferred practice of our invention, a novel epoxy tooling composition that can be used in casting high temperature injection molding or SMC molding tools is provided. The epoxy tools cast from this composition can be used at molding temperatures higher than 150° C. Based on a heat deflection temperature of 181° C. obtained on our resin composition, we recommend a maximum use temperature of 200° C. for a molding tool cast from our composition when 75 volume percent of filler is added. The viscosity of our epoxy tooling composition is sufficiently low such that even at filler loadings as high as 75 volume percent, it can still be poured into a mold having thin sections and bulk sections. The term "bulk section" in an epoxy tool is defined as a section having a thickness of much larger than 1/4 inch. The term "thin section" is defined as a section having a thickness of less than 1/4 inch.
We have previously discovered that in order to cast a bulk section tool, the reaction exothermic heat given out by the epoxy during curing must be controlled. Since the amount of exothermic heat per unit weight of epoxy is fixed, we have devised a unique casting method to avoid any potential over-heating problem. First, to minimize the total amount of exothermic heat produced by the epoxy curing reaction, we use the least amount of epoxy by utilizing a system of interstitially-matched fillers. Other workers have attempted to use large amounts of fillers in rapid cure epoxy systems without success. This is because that when filler loadings above a critical level are added to an epoxy casting composition, the viscosity of the composition increases to such an extent that it is no longer pourable.
We have discovered that by interstitially matching the particle size of the fillers, the viscosity of the filled epoxy composition can be maintained at constant level even at very high filler loadings. By interstitially matching the fillers, we carefully select filler particles of different sizes such that smaller particles would fit in the interstices between larger particles. When this critical requirement is met, a total filler loading as high as 75 volume percent may be used while the pourability of the epoxy composition is maintained.
Another benefit of using high loadings of fillers is that the fillers serve as a heat buffer absorbing the exothermic heat evolved from the curing reaction. As a result, potential formations of thermal shocks or localized heat pockets which may lead to excessive shrinkage or deformation in the tool are avoided.
Our novel epoxy composition comprises a bisphenol-A type epoxy resin, a trifunctional aromatic epoxy resin, an anhydride curing agent, an imidazole catalyst, and optionally an interstitially-matched filler system. We have found that the exact combination of our unique composition of the two epoxy resins, the anhydride curing agent, and the imidazole catalyst is critically important. Replacing any one component with another ingredient would result in a severe loss of physical properties such as the heat deflection temperature and the tensile properties. Three interstitially-matched filler systems were used in our preferred embodiments. When used in an amount as high as 75 volume percent of the total composition, the exothermic heat evolved from the curing reaction of the composition is significantly reduced. Our novel epoxy tooling composition can be cured in two steps. The first step of pre-cure can be carried out either at room temperature for 2 days or at 60° C. for 8 hours. After the pre-cure, the mold making frames are removed and the tool is then postcured at 180° C. for 2 hours.
Other objects, features and advantages of the present invention will become apparent upon consideration of the specification that follows.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The practice of using an interstitially-matched filler system in which the smaller particulate fillers fit in the interstitial spacings between the larger and medium size particulate fillers was first proven by us by using a commercial epoxy system. This commercial epoxy system Magnolia 6013A was obtained from the Magnolia Plastics Company. It contains 27 volume percent iron particles of 20 micron size. To test our interstitially-matched filler system, we first added a second filler of iron particles having 126 micron size to observe the effect of this second filler on the viscosity. A drastic increase in viscosity from 70×10 3 centipoise at 27 volume percent iron particle loading to 470×10 3 centipoise at 33 volume percent iron particle loading was observed, i.e., a seven-fold increase in viscosity caused by an 8 volume percent increase in the iron powder loading. Our experience indicated that when a viscosity of 150×10 3 centipoise is reached, the fluidity of the casting composition is reduced to such an extent that the composition is no longer pourable.
We next tried our interstitially-matched filler system by using an iron particle having particle size of 279 microns. By gradually increasing the total iron powder loading to 40 volume percent, the viscosity of the system is increased from 70×10 3 to only 100×10 3 centipoise. At 100×10 3 centipoise viscosity, the casting composition can be poured into thin mold sections with no flow problem.
Compounding for our novel composition was carried out in a Ross mixer. The first epoxy resin used in our composition is a diglycidyl either supplied by the Ciba-Geigy Co. under the tradename of Araldite® 6005. This epoxy resin has an approximate epoxy equivalent weight of about 180 to 196 and a viscosity at 25° C. in the range of about 7500 to 9500 centipoise. Other commercial products that are substantially equal to this epoxy compound are Dow Chemical D.E.R.® 330 resin, Celanese Epi-Rez® 509, and Shell Epon® 826.
The second epoxy resin ingredient used in our composition is a trifunctional aromatic epoxy of triglycidyl p-aminophenol supplied by the Ciba-Geigy Co. under the tradename of Araldite® 0510. This epoxy resin has an approximate epoxy equivalent weight of about 95 to 107 and a viscosity at 25° C. in the range of about 550 to 850 centipoise. Another commercial product which we have found that works equally well is Tactix® 742 supplied by the Dow Chemical Company.
Our novel composition can be pre-cured at room temperature in approximately 2 days or at 60° C. in approximately 8 hours. This pre-cure step allows the mold frame to be made of conventional materials such as wood, plaster, and clay by a conventional frame making technique. After this initial cure, the frame is taken apart and the wood, plaster, or clay removed. The mold is then postcured at 180° C. for 2 hours, with no dimensional change.
To accomplish this two stage curing process, we have used an anhydride curing agent and an imidazole accelerator. The anhydride we have used is nadic methylanhydride supplied by the Ciba-Geigy Co. under the designation of hardener 906. It has a viscosity at 25° C. of 175 to 275 centipoise, an anhydride content of 93% and a boiling point of 278° C. The imidazole accelerator used is a 1-(2-hydroxypropyl)-2-methylimidazole supplied by Archem Co. under the designation of AP-5. It has a room temperature viscosity of 1000 centipoise and a boiling point of 465° F.
Formulations and physical properties of six compositions, including our novel invention as composition #1, are shown in table 1.
TABLE I______________________________________Composition I II III IV V VI______________________________________Araldite ® 6005 100 100 100 100 100 100Araldite ® 0510 25 -- -- -- 25 25Epi-Rez ® 5048 -- -- 25 -- -- --Araldite ® MY-720 -- -- -- 25 -- --Hardener 906 112 112 112 112 -- 112MTPHA -- -- -- -- 112 --AP-5 4 4 4 4 4 --XU-213 -- -- -- -- -- 4HDT, °C. 181 155 155 181 147 153Tens. Strength, MPa 87.0 61.4 52.7 34.6 83.3 67.1Tens. Modulus, GPa 2.5 2.8 3.3 2.9 3.4 3.0Comp. Strength, Mpa 122.5 124.2 112.4 126.2 113.9 126.2Comp. Modulus, GPa 2.0 2.2 1.8 1.9 2.3 2.3______________________________________
The different ingredients shown in Table I are described as follows. Epi-Rez® 5048 is a triglycidyl aliphatic ether supplied by the Celanese Co. Araldite® MY-720 is a tetraglycidyl methylenedianiline supplied by the Ciba-Geigy Co. MTPHA is methyltetrahydrophthalic anhydride, commercially available from the Archem Co. XU-213 is a boron trichloride amine complex supplied by the Ciba-Geigy Co.
The physical properties of the six epoxy compositions were determined by following standard ASTM test procedures. For instance, the heat deflection temperature (HDT) was determined by ASTM D-648 at 264 psi. The tensile strength (Tens. Strength) and tensile modulus (Tens. Modulus) were determined by ASTM D-638. The compressive strength (Comp. Strength) and compressive modulus (Comp. Modulus) were determined by ASTM D-695.
We have found that the use of other materials to replace any of the ingredients in composition I results in significant loss in properties. For example, if methyltetrahydrophthalic anhydride (MTHPA) is used instead of nadic methylanhydride (NMA), the HDT drops to 140° C., and the tensile strength drops 25%. If AP-5 is replaced by another catalyst such as benzyl dimethlyamine (BDMA) or a boron trichloride amine complex, the HDTs drop to 162° C. and 153° C., respectively, and the tensile strength drops 23%. If our trifunctional aromatic epoxy Araldite® 0510 is replaced by another multifunctional epoxy such as a tetrafunctional aromatic epoxy Araldite® MY-720 or an aliphatic epoxy Epi-Rez® 5048, the HDT is lowered to 155° C. with 5048, and the tensile strength drops 40% with MY-720. The use of other liquid epoxies of similar molecular weight to Araldite® 6005 such as Dow D.E.R.® 330 or Epi-Rez® 509 does not affect the properties.
Additionally, the composition without NMA, and cured with BDMA or boron trihalide, would require much higher initial cure temperature (>110° C.), which would damage the frame making materials, and would also require a longer post cure. This would still result in a lower HDT (about 150° C.). If cured with only a substituted imidazole such as AP-5, there is a risk of an uncontrollable exotherm.
The amounts of the ingredients used in Composition I can be varied in the ranges of 20-30 parts for 0510, 110-115 parts for 906, and 2-6 parts for AP-5. The 6005 resin can be replaced with other epoxies of similar molecular weight such as Dow D.E.R.® 330 or Celanese Epi-Rez® 509. It may also be replaced with Novalacs such as D.E.N.® 431. The multifunctional epoxy 0510 can be replaced with a new material, Dow's Tactix® 742.
The first interstitially-matched filler system used in our novel epoxy composition comprises two silicon carbide particles and one silica particle. The parts by weight of each filler used is shown in Table II as IA. The silicon carbide particles were selected for their superior abrasion resistance resulting in a forming tool having superior durability. The silica particle was selected for its rigidity and low cost. Two different sized particles of silicon carbide were used. They are both available commercially from the Sohio Company. Silicon carbide SiC 100 has particle sizes in the range between 63 to 203 microns with an average particle size of 122 microns. SiC 400 has particle sizes in the range between 1 to 25 microns with an average particle size of 4 microns. A fine particle size silica Si-21 commercially available from Whittaker, Clark & Daniels Inc. was selected to fit in between the larger SiC particles. Si-21 has a particle size distribution of 51% <5 microns, 90% <15 microns and an average particle size of 2 microns.
Two other filler systems that we have also found adequate for our epoxy composition, IB and IC, are shown in Table II. In both systems, either silica alone or silica and aluminum combination may be used in place of silicon carbide and silica. Si-85 is an 85 mesh washed silica sand supplied by the Weldron Silica Co. AL-120 is an aluminum powder supplied by the Alcoa Co. It has an average particle size between 25 to 30 microns with 95% smaller than 44 micron and containing 99.7% aluminum. Si-23 is another silica commercially available from Whittaker, Clark & Daniels Inc. It has a particle size distribution of 80% <200 mesh, 70% <325 mesh and an average size of 125 microns.
TABLE II______________________________________Composition IA IB IC______________________________________Resin I 241 241 241SiC-100 400 -- --SiC-400 150 -- --Si-85 -- 400 --Al-120 -- -- 400Si-23 -- 150 150Si-21 120 120 120Tens Strength,MPa 60.7 43.8 50.6Tens Modulus,GPa 13.8 14.2 11.6Comp Strength, MPa 188.7 187.9 145.7Comp Modulus, GPa 3.9 4.0 3.4Flex Strength, MPa 84.4 72.8 83.1Flex Modulus, GPa 11.9 9.9 10.1______________________________________
To compound our novel epoxy formulation, we mix all the fillers in a rolling drum mixer. After each component filler is weighed according to its part by weight, they are put into a drum and then rolled in the mixer for a period of 3 hours. The mixing speed is approximately 10 to 20 revolutions per minute.
Suitable amounts of epoxies, curing agent and catalyst are then weighed and poured into a stainless steel bowl in a Ross mixer. A pre-mixed filler system is then added to the stainless steel bowl. The total ingredients are mixed by a motor driven mixing blade under 30 inches of vacuum for 1 hour. The vacuum was applied to degas any air bubbles generated during the mixing process. The mixed epoxy formulation has a shelf life of approximately 2 days.
The procedure for casting a plastic forming tool used in a sheet metal stamping process is adequately described in U.S. Pat. No. 4,601,867 issued July 22, 1986. When casting a large size forming tool, other physical reinforcement such as a steel wire mesh may also be used to improve the structural integrity of the mold.
Our novel high temperature epoxy casting composition can be pre-cured either at room temperature for 2 days or at 60° C. for 8 hours, then postcured at 180° C. for 2 hours. When filled to a level of 75 volume percent filler content, it can be used at mold temperatures as high as 200° C. This is a significant improvement over the commercially available epoxy tooling compounds which are recommended for a maximum use temperature of 150° C. only. Our novel composition does not contain aromatic amines, which are generally considered to be a toxicological hazard. Furthermore, our interstitially-matched filler system enables the use of very high loadings of fillers while maintaining the fluidity of the filled composition.
While our invention has been described in terms of three specific embodiments thereof, other forms could be readily adopted by one skilled in the art to achieve the same results. For instance, any combination of other suitable filler particles having suitable particle sizes may be combined to form our interstitially-matched filler system. The only critical requirement to be met is that they must be interstitially-matched such that even when used at a high volume percent they do not significantly increase the viscosity of the total blended epoxy system. Other filler particles having good rigidity and abrasion resistance may suitably be used in place of silicon carbide, silica, and aluminum particles.
|
A tough, durable, high temperature epoxy tooling composition for making cast-to-size forming tools. The composition comprises a bisphenol-A epoxy, a trifunctional aromatic epoxy, an anhydride catalyst, and an imidazole catalyst. The composition may optionally contain a filler system comprising filler particles having different diameters that are interstitially-matched.
| 2
|
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a National Phase Application of International Application No. PCT/GB2008/003356, filed Oct. 3, 2008, which claims priority to Great Britain Patent Application No. 0719390.7 filed Oct. 4, 2007, which applications are incorporated herein fully by this reference.
FIELD OF THE INVENTION
The invention relates to the purification of water and, in particular, to an evaporation device for use in purifying water.
BACKGROUND TO THE INVENTION
There is an increasing demand for water suitable for drinking and irrigation. Consequently there is an increasing demand for purifying impure water, such as sea water.
German Patent Application No. 10230668 describes a scheme for purifying “raw” water in which air is humidified as it passes across an arrangement of rods while the raw water is dripped over the surface of the rods. A condenser is then used to extract purified water from the humidified air.
European Patent Application No. 1 362 833 A2 discloses a water purification apparatus comprising a water source and a hydrophilic membrane. The hydrophilic membrane allows water to pass through the membrane as a vapour, and prevents impurities passing through. That patent specification contains a description of suitable hydrophilic materials, and also the results of experiments conducted in using bags made from hydrophilic material for irrigating plants.
SUMMARY OF THE INVENTION
According to a first aspect of the invention there is provided an evaporation device for use in purifying water, comprising a first tube arranged within a second tube, wherein the first tube comprises a hydrophilic membrane, and wherein a gap is provided between the first and second tubes for the flow of air.
Therefore the invention provides an evaporation device (or, alternatively, a pervaporation device) having an inner tube comprising a hydrophilic membrane, arranged inside an outer tube, with a gap between the tubes for the flow of air. In use, impure water in the inner tube can pervaporate through the inner tube and humidify air in the gap. The use of an inner tube arranged within an outer tube channels the air close to the hydrophilic membrane to provide efficient humidification. It also provides a structure that can be readily heated by solar radiation incident on the outer tube, in particular to heat the air in the gap. This enhances the convection of the air through the device and results in warmer air, which is able to carry a greater amount of water vapour than colder air, being present in the gap. This improves the humidification capacity of the device.
In one embodiment, the first tube is arranged substantially coaxially with the second tube. Such an arrangement can provide efficient humidification and is simple to manufacture. In other embodiments, at least a portion of the first tube may be coiled or arranged in a zig-zag configuration. The coil is preferably substantially coaxial with the second tube. Likewise, the zig-zag would usually be arranged centrally in the outer tube. The inner tube itself may be smooth or corrugated. Generally, arrangements that can provide a large surface area of the hydrophilic membrane, whether by coiling, zig-zags, corrugation or otherwise, provide more efficient humidification.
The gap may contain means for creating turbulence in air flowing through it. The turbulence causes drag, causing the air to spend longer in the device. So, the air has more time to take up pervaporated water molecules from the surface of the hydrophilic membrane. Overall, take up of moisture by the air is thereby promoted. The means for creating turbulence may comprise fins attached to either or both of the outside of the first tube and the inside of the second tube. Additionally or alternatively, either or both of the outside of the first tube and the inside of the second tube could be rough or undulating, e.g. corrugated or threaded.
The second tube may comprise metal, for example copper. This improves absorption and conduction of heat from the outside of the second tube to the inside of the second tube, thereby helping to optimise heat transfer to the air in the gap.
The inside of the second tube may be coated with a black substance. This improves radiation of heat from the inside surface of the second tube to the air in the gap.
The first and second tubes are preferably arranged not to touch each other in the gap, for example by suspending one or both of the tubes, or by employing a spacer. This feature facilitates air flow over the whole outer surface of the first tube.
The evaporation device may comprise an evaporation module for housing the evaporation device. The evaporation module may comprise an elongate housing with an outwardly curved window. This serves to improve the collection of solar radiation, by acting in a similar manner to a greenhouse. This can further improve heating of the evaporation device and, in particular, air in the gap.
According to a second aspect of the invention, there is provided a system for purifying water, comprising:
a water inlet channel for supplying impure water;
an evaporator for humidifying air by pervaporation using the impure water supplied by the water inlet channel; and
a condenser for condensing purified water from the air humidified by the evaporator, the condenser being cooled by the impure water supplied by the water inlet channel before it is supplied to the evaporator.
Also, according to a third aspect of the present invention, there is provided a method of purifying water, comprising:
supplying impure water through an inlet channel;
humidifying air with an evaporator by pervaporation using the impure water supplied by the water inlet channel; and
condensing purified water from the humidified air with a condenser that is cooled by the impure water supplied by the inlet channel before it is supplied to the evaporator.
In this way, the impure water used for humidification may also be used for effecting condensation. This avoids the need for separate supplies of water for the evaporator and the condenser. Importantly, the impure water is heated during the condensation process, with a result that the water supplied to the evaporator is warmer than if it were supplied to the evaporator directly. This has the benefit of facilitating humidification and condensation with effectively no net increase in the overall energy requirements of the system.
The water inlet channel may comprise heating means for heating the impure water after it is supplied to the condenser and before it is supplied to the evaporator. Heating the impure water can improves humidification. However, the condensation is still effected at the temperature at which the impure water is initially supplied, prior to heating the impure water by the heating means. Another advantage of this arrangement is that convection of the impure water in the heating means it can facilitate flow of the impure water through the water inlet channel. However, in some embodiments, for example where there is a large head between the source of the impure water and an outlet from the system, this may not be sufficient to facilitate flow of the impure water through the water inlet. So, a pump may be provided for propelling water through the water inlet channel.
The heating means may be arranged to employ solar energy, which enables low cost operation and a low environmental impact.
The water inlet channel may comprise a sediment trap. This feature reduces the likelihood of sediment inhibiting the flow of impure water in the system.
The evaporator may comprise the evaporation device described above. The first and second tubes may be arranged substantially vertically with the air inlet below the air outlet. This arrangement facilitates the flow of air in the gap by convection.
However, the system may comprise forcing means for forcing the air through the gap. For example a fan may blow or suck the air. This feature can increase the volume of air that is humidified and enhance the take up of the water vapour by the air.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described, by way of example, only, with reference to the accompanying drawings, wherein:
FIG. 1 is a perspective view of a first preferred embodiment of an evaporation device;
FIG. 2 is a cross-section through the evaporation device of FIG. 1 , along the line X-X;
FIG. 3 is a cross-section through the evaporation device of FIG. 1 , along the line Y-Y;
FIG. 4 is a perspective view of a second preferred embodiment of an evaporation device;
FIG. 5 is a perspective view of a third preferred embodiment of an evaporation device;
FIG. 6 is a schematic block diagram of a water purification system;
FIG. 7 is a perspective view of an evaporator module; and
FIG. 8 is a cross-section through the evaporator module of FIG. 7 , along line Z-Z.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 to 3 , there is illustrated an evaporation device 100 having an inner tube 10 and an outer tube 20 . The inner tube 10 is made of a hydrophilic membrane, such as Dutyion™. Suitable hydrophilic membranes are described in EP 1 362 833 A2. The outer tube 20 is preferably made of a material that readily absorbs solar radiation and is good heat conductor, such as a metal, for example copper, although other materials, such as plastics, are suitable. The inside 22 of the outer tube 20 may be coated with a black substance, such as a black paint, to encourage the radiation, inside the outer tube 20 towards the inner tube 10 , of heat which has been absorbed by the outer tube 20 .
There is a gap 30 between the inner tube 10 and the outer tube 20 for the flow of air. In FIGS. 1 to 3 , the inner tube 10 and the outer tube 20 are arranged substantially coaxially to facilitate the flow of air, although this is not essential. Preferably the inner tube 10 does not touch the outer tube 20 , thereby enabling air to flow in the gap all around the inner tube 10 ; this may be implemented, for example, by providing a spacer 40 . Another suitable means of arranging that the inner tube 10 and outer tube 20 do not touch is to suspend the inner tube 10 inside the outer tube 20 by a cord or a wire.
In use, the inner tube 10 contains water, which may be impure water such as sea water. One end 12 of the inner tube 10 may be connected to a source of such water via a pipe, for which purpose a connector (not illustrated in FIGS. 1 to 3 ) may be provided at the end 12 . Furthermore, water may be channelled away from the end 14 of the inner tube 10 via a further pipe, for which purpose a connector (not illustrated in FIGS. 1 to 3 ) may be provided at the end 14 .
The inner tube 10 and outer tube 20 illustrated in FIGS. 1 to 3 have a circular cross-section, but this is not essential. A square, or other shape, cross-section would be suitable.
It is advantageous if the air flow within the gap 30 between the inner tube 10 and the outer tube 20 is turbulent, as this facilitates the take up of moisture into the air from the hydrophilic membrane of the inner tube 10 . The turbulent air flow causes drag and this drag causes the air to take longer to pass through the gap 30 , thereby giving the air longer to humidify. So, the evaporation device 100 may include means for creating turbulence, such as obstacles in the air path. Such obstacles may be provided on the outside of the inner tube 10 , on the inside of the outer tube 20 , or on both. In the embodiment illustrated in FIGS. 1 to 3 , the evaporation device 100 has fins 50 arranged on the inside of the outer tube 20 for creating turbulence.
In second and third preferred embodiments, illustrated in FIGS. 4 and 5 , the inner tube 10 is not arranged coaxially with the outer tube 20 but is, respectively, coiled or has a zig-zag configuration within at least part of the outer tube 20 . These configurations allow the inner tube 10 have to a greater surface area of hydrophilic membrane for a given length of outer inner tube 20 , which improves humidification of the air flowing in the gap 30 . Other configurations of the inner tube 10 may be used. Whatever configuration is used, it is considered useful to ensure that there are no cusps in the inner tube 10 , as water droplets tend to form in or near the cusps in the hydrophilic membrane, which is undesirable.
Referring to FIG. 6 , there is illustrated a water purification system 500 comprising an evaporation device 100 as described above with reference to FIGS. 1 to 5 . One or more such evaporation devices 100 may be used; in FIG. 6 an evaporator 510 comprising a bank of five evaporation devices 100 is illustrated. To enable modular assembly of such a bank of evaporation devices 100 , the inner tube 10 of each evaporation device 100 may be provided with a snap-fit connector which may be self opening so that the evaporation device 100 automatically becomes part of the water circuit when it is added to the bank, and self closing when it is removed from the bank. Preferably, each evaporation device 100 is arranged with its outer tube 20 substantially vertical, in order to facilitate the flow of air upwards in the gap 30 by convection.
The water purification system 500 also comprises a water inlet channel 520 for conveying impure water to the inside of the first tube 10 of each evaporation device 100 . As the impure water is vaporised through the hydrophilic membrane in the evaporation device 100 and humidifies the air in the gap 30 , replacement impure water enters the first tube 10 through the water inlet channel 520 . In the evaporator 510 illustrated in FIG. 6 , the first tube 10 of each evaporation device 100 is coupled in parallel to the water inlet channel 520 .
The water purification system 500 also comprises an air inlet 512 for supplying air 516 to the gap 30 of each evaporation device 100 . When each evaporation device 100 is arranged with its outer tube 20 substantially vertical, the air inlet 512 is preferably at the lower end of the evaporation device 100 , because air in the gap 30 will naturally rise by convection when heated. Such an air inlet 512 may be provided by installing the lower end of each evaporation device 100 above ground level. An air outlet 514 for extracting air 518 from the gap 30 of each evaporation device 100 is provided at the upper end of each evaporation device 100 .
A condenser 530 condenses water vapour from the humidified air, thereby forming purified water. Preferably the condenser 530 is arranged above the evaporator 510 so that the humidified air can readily pass into the condenser 530 . In other embodiments, an air path, such as ducting or such like, may be provided between the evaporator 510 and the condenser 530 to channel the humidified air from the evaporator 510 to the condenser 530 . The purified water may be extracted from the condenser 530 by way of an outlet 535 .
The evaporation devices 100 may be arranged to be heated by solar energy. This is absorbed by the outer tubes 20 of the evaporation devices 100 and then, in turn, heats the air within the gaps 30 and, to a lesser degree, the impure water within the inner tubes 10 . The pervaporation process is improved by this heating as there is a greater amount of evaporative energy available. Similarly, overall humidification is improved by the heating because warm air can hold more water vapour than cold air. Also, as the air in the gaps 30 is heated, air flows by convection, drawing in un-humidified air through the bottom of the evaporation devices 100 and causing more air to be humidified.
As illustrated in FIG. 6 , the condenser 530 may be located in the water inlet channel 520 such that the impure water passes through the condenser 530 on its way to the evaporator 510 . At the condenser 530 , the impure water would normally be relatively cold, as it may be drawn from the sea or a ground water supply. It can therefore operate to keep the condenser 530 cool and facilitate the condensing. The temperature of the impure water is also raised in the condenser 530 before it reaches the evaporator 510 . This has the benefit of further heating the evaporator 510 and thereby improving the pervaporation process and humidification, for the same reasons as stated above.
The water inlet channel 520 comprises an optional heater 540 for heating the impure water prior to supplying the heated impure water to the evaporator 510 . This can also improve the pervaporation process and humidification of the air, as stated above. The heater 540 may be, for example, a solar heat sink operating from solar energy thereby reducing the environmental impact of the system 500 . If a heater 540 is employed to heat the impure water and also the impure water is passed through the condenser 530 , the heater 540 should be located downstream of the condenser 530 , such that the condenser 530 receives the coolest possible impure water. Heating the water in the heater 540 can also provide convection in the impure water in the part of the inlet channel 520 inside the heater 540 , sufficient to cause flow of the water through the channel 520 . Even without the heater, water heated elsewhere in the system will aid water circulation by convection.
The air inlet 512 comprises an optional fan 550 for forcing air through the gap 30 . The fan 550 may be arranged to blow or suck the air through the gap 30 . In this way a greater flow rate of air may provided, which can improve take up of the water vapour by the air.
The water inlet channel 520 comprises an optional sediment trap 560 for reducing the likelihood of sediment inhibiting the flow of impure water in the system 500 . The sediment trap 560 is preferably located upstream of the condenser 530 , heater 540 and the evaporator 510 .
Also, in the embodiment illustrated in FIG. 6 , there is a water outlet channel 570 for extracting impure water from the inner tube 10 of each evaporation device 100 in the humidifier 510 . This enables a flow of impure water to be established, which enables freshly heated impure water to flow into each evaporation device 100 , thereby bringing the stated benefits of heated water, and also reducing the likelihood of sediment accumulating in the evaporator 510 or in the constituent parts of the water inlet channel 520 , which could reduce efficiency of the system 500 . Optionally, a pump 580 may be provided for pumping the impure water through the water inlet channel 520 to the water outlet channel 570 , thereby improving the flow of the impure water. The pump 580 may be solar powered to provide low cost operation and low environmental impact. Water emerging from the water outlet channel 570 may be returned to the source 590 of impure water, such as the sea, a well, or, a reservoir.
Optionally, impure water from the water outlet channel 570 may coupled back to the water inlet channel 520 , with only the water lost through pervaporation needing to be replaced from the source of impure water. In this way impure water is re-used, which reduces the requirement for a supply of replacement impure water, making the system 500 suitable for purifying water in locations that do not have a plentiful supply of impure water.
Referring to FIGS. 6 and 7 , in another preferred embodiment of the invention, the evaporation devices 100 may be housed in evaporation modules 600 . Each module 600 comprises a housing 610 with a window 620 . The housing 610 is elongate and can accommodate one or more evaporation devices 100 . It is preferably made of an insulating material.
The window 620 is preferably curved outwardly from the housing 610 . This helps to maximise the amount of solar radiation collected by the module 600 . The inside surface of the window 620 preferably has a coating that reduces the amount of solar radiation that escapes from the module 600 through the window 620 .
In use, the module 600 may be mounted in a position where it receives a large amount of solar radiation, e.g. on the outside of a building. Alternatively, it may be portable. The received solar radiation is collected in the module 600 due to the insulative nature of the housing 610 and the inward reflectiveness of the window 620 , e.g. like an efficient greenhouse. Heating of the evaporation device(s) 100 in the module 600 by solar radiation is therefore improved.
The evaporator 510 of the system 500 illustrated in FIG. 6 may comprise one or more evaporation modules 600 . The number of evaporation modules 600 can be varied in the same way as the number of evaporation devices 100 .
The system 500 may also be adapted in other ways to suit the prevailing circumstances in different locations. For example, different forms of condenser 530 may be employed. In a cold region of the world, a sheet of glass, for example part of a building, cooled by the ambient temperature may be sufficient for performing the required condensation, whereas in other locations having an ample supply of solar energy, a powered condenser using active cooling, for example actively cooled fins, may be more appropriate.
Reference in the specification and claims to humidification (or equivalently hydration), purification and heating are not intended to signify any predetermined, respectively, humidity, purity and temperature, but merely signify an increase in, respectively, humidity, purity and temperature.
|
An evaporation device has an inner tube and an outer tube. The inner tube is made of a hydrophilic membrane, such as DutyionT. The outer tube is preferably made of a material that readily absorbs solar radiation and is a good heat conductor. There is a gap between the inner tube and the outer tube for the flow of air. The inner tube contains a flow of impure water. The hydrophilic membrane allows water to pass to the outside of the inner tube as vapor, but prevents impurities from passing through. Air flowing in the gap takes up the water vapor and humidified air exits the evaporation device. This humidified air is subsequently cooled to collect the vapor and provide purified water, e.g. at a condenser.
| 8
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a Continuation of application Ser. No. 10/570,156 filed Mar. 27, 2006, which in turn is a National Phase Application of PCT/JP2004/013791 filed Sep. 22, 2004. This application claims the benefit of Japanese Patent Application No. JP 2003-333664, filed Sep. 25, 2003. The entire disclosures of the prior applications are hereby incorporated by reference herein in its entirety.
BACKGROUND
[0002] The invention relates to substrate treatment equipment for treating a substrate of a semiconductor device or the like, and a manufacturing method of the substrate.
[0003] As is generally known, there is equipment as this type of substrate treatment equipment, which has a substrate holder for holding substrates in a multistage manner and a transfer unit for transferring the substrates into the substrate holder, and treats the substrates in a treatment furnace while holding a number of substrates in the substrate holder.
SUMMARY
[0004] When the substrates are heated in the treatment furnace, or removed from the treatment furnace and then cooled, abnormal phenomena such as cracks or warps may occur in the substrates due to thermal stress. When the cracks or warps are in such a level that they result in disabling automatic carrying of the substrates by an automatic substrate carrying mechanism, tweezers for taking in and out the substrates may collide with the substrates, and push down the substrate holder, leading to a serious accident such as damage of a quartz component.
[0005] To solve this, a mechanism for sensing a condition of the substrates can be considered to be provided. For example, the sensing mechanism has a photo-sensor provided on the transfer unit, and senses the substrates in the substrate holder by moving the photo-sensor using a vertical shaft of the transfer unit.
[0006] Portions where light is intercepted by the substrates and portions where light is transmitted between the substrates are recorded, and a shift level of the vertical shaft and sensing data of the photo-sensor are used to find whether a substrate pitch is normal with respect to a pitch of the substrate holder which has been known.
[0007] When a substrate drops from a support slot on the support holder due to cracking of the substrate or transfer errors, discrepancy may occur between interception/transmission data of light by the photo-sensor and the recorded data, and a substrate on a support slot at which the discrepancy appeared is determined to be in an abnormal transfer condition.
[0008] Moreover, when the substrate completely drops from a support slot and consequently the substrate does not lie on the support slot on which the substrate is essentially to be held, since light is not intercepted, the substrate can be sensed as a lost substrate.
[0009] After a substrate condition is sensed by the substrate sensing mechanism, a substrate that has been transferred onto the support slot at which an error occurred is manually collected by an operator who has entered the equipment.
[0010] Furthermore, after the substrate has been visually confirmed to be safe, it is automatically transferred by the automatic substrate carrying mechanism.
[0011] Currently, it is an issue to realize a mini-environment by using an L/L device (load/lock device), a N 2 purge device, and an organic filter and the like in order to avoid entering of moisture or particles contained in the air and thus reduce contamination of the substrate in substrate treatment equipment. When an abnormal substrate is manually collected after an abnormal phenomenon is sensed by the substrate condition sensing mechanism as describe above, particles generated from a human body may have adverse effects on a substrate in a normal condition at high possibility. In substrate treatment equipment using the N 2 purge device, an atmosphere within the equipment must be returned to the air to reset the environment such that the operator can enter the equipment. In such a situation, a natural oxidation film on a surface of the substrate can not be reduced, consequently a substrate that has been normally transferred also has a problem in process.
[0012] An object of the invention is to provide substrate treatment equipment that can automatically collect a substrate in a normal condition without needing manual operation.
[0013] To solve the problem, a first feature of the invention is substrate treatment equipment having a substrate treatment chamber, a substrate holder that can be inserted into the substrate treatment chamber and holds substrates in a multistage manner in a substantially vertical direction, a substrate transfer unit for transferring the substrates onto the substrate holder, and a sensing device for sensing a holding condition of the substrate held in the substrate holder; which includes a control device that, in transfer of the substrates, senses the holding condition of the substrates using the sensing device, and controls the substrate transfer unit such that substrates other than a substrate which was determined to be in an abnormal substrate holding condition are transferred by the substrate transfer unit.
[0014] A second feature of the invention is substrate treatment equipment having a substrate treatment chamber, a substrate holder that can be inserted into the substrate treatment chamber and holds substrates in a multistage manner in a substantially vertical direction, a substrate transfer unit for transferring the substrates onto the substrate holder, and a sensing device for sensing a holding condition of the substrate held in the substrate holder; which includes a control device that, in transfer of the substrates, senses the holding condition of the substrates using the sensing device, and controls the substrate transfer unit such that substrates other than a substrate which was determined to be in an abnormal substrate holding condition are transferred by the substrate transfer unit; wherein the control device controls the substrate transfer unit such that substrates other than the substrate determined to be abnormal and at least one of substrates held on and under the substrate determined to be abnormal are transferred by the substrate transfer unit.
[0015] A third feature of the invention is a manufacturing method of a substrate having a step of inserting a substrate holder in which substrates are held in a multistage manner in a substantially vertical direction into a substrate treatment chamber, a step of performing heat treatment to the substrates in the substrate treatment chamber, a step of sensing a holding condition of the substrates held in the substrate holder, and a step of transferring substrates other than a substrate that was determined to be in an abnormal substrate holding condition by a substrate transfer unit.
[0016] A fourth feature of the invention is a manufacturing method of a substrate having a step of inserting a substrate holder in which substrates are held in a multistage manner in a substantially vertical direction into a substrate treatment chamber, a step of performing heat treatment to the substrates in the substrate treatment chamber, a step of sensing a holding condition of the substrates held in the substrate holder, and a step of transferring substrates other than a substrate that was determined to be in an abnormal substrate holding condition by a substrate transfer unit; wherein the substrates are transferred in such a manner that substrates are carried for each of several predetermined number of substrates, and when all the predetermined number of substrates to be carried are determined to be in a normal substrate holding condition, all the predetermined number of substrates are carried together, and when at least one of the substrates is determined to be in an abnormal substrate holding condition, substrates other than the substrate that was determined to be abnormal in the predetermined number of substrates are carried one at a time.
[0017] While control means may control the transfer unit such that all the substrates other than the substrate that was determined to be abnormal are transferred by the transfer unit, it preferably controls the transfer unit such that substrates other than the substrate that was determined to be abnormal and at least one of substrates on and under the substrate are transferred by the transfer unit.
[0018] According to the substrate treatment equipment of the invention, in transfer of substrates, the holding condition of the substrates is sensed, and the transfer unit is controlled such that substrates other than at least a substrate that was determined to be abnormal are transferred by the transfer unit, therefore substrates in a normal condition can be automatically collected, and entering of particles into the equipment or oxidation on the substrates can be prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a perspective view generally showing substrate treatment equipment according to an embodiment of the invention;
[0020] FIG. 2 is a cross section view generally showing the substrate treatment equipment according to the embodiment of the invention;
[0021] FIG. 3 is a cross section view showing a treatment furnace used in the substrate treatment equipment according to the embodiment of the invention and the periphery of the furnace;
[0022] FIG. 4 is a side view showing a substrate transfer unit used in the substrate treatment equipment according to the embodiment of the invention;
[0023] FIG. 5 is a side view showing a substrate holder used in the substrate treatment equipment according to the embodiment of the invention;
[0024] FIG. 6 is views for illustrating an abnormal condition of substrate holding in the substrate treatment equipment according to the embodiment of the invention, wherein (a) is a plane view showing a normal condition, (b) is a front view showing a condition of cracking in a substrate, (c) is a front view showing the substrate holder, and (d) is a side view of the substrate holder;
[0025] FIG. 7 is views for illustrating a sensing method when an abnormal condition of substrate holding is found in the substrate treatment equipment according to the embodiment of the invention, wherein (a) is an illustrative view showing a relation between the abnormal condition of substrate holding and a sensing waveform, and (b) is a plane view of the substrate transfer unit; and
[0026] FIG. 8 is a flowchart showing operation of substrate sensing in the substrate treatment equipment according to the embodiment of the invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0027] Next, an embodiment of the invention is described according to drawings.
[0028] FIG. 1 and FIG. 2 show substrate treatment equipment 10 according to the embodiment of the invention. The substrate treatment equipment 10 is vertical-type one for performing diffusion treatment or CVD treatment to a substrate. In the substrate treatment equipment 10 , a load/unload stage 18 for inserting a pod 14 accommodating substrates 12 formed from silicon and the like from the outside into a housing 16 is fixed on a front face of the housing 16 . A cassette shelf 22 for storing the inserted pod 14 is provided within the housing 16 . Moreover, an N 2 purge chamber 24 is provided within the housing 16 . The N 2 purge chamber 24 acts as a carrying area of the substrates 12 , or a space for carrying in and out a substrate holder (boat) 26 . When treatment of the substrate 12 is performed, the N 2 purge chamber 24 is filled with inert gas such as N 2 gas to prevent a natural oxidation film from being formed on the substrate 12 .
[0029] FOUP is used for the pod 14 , and the substrate 12 can be carried while being isolated from the air by covering an opening provided in a side face of the pod 14 by a cap (not shown), and the substrate 12 can be taken in and out into/from the pod 14 by removing the cap. For example, 25 substrates 12 are stored in the pod 14 . A pod opener 28 is provided in a front face of the N 2 purge chamber 24 so that the cap of the pod 14 is removed to communicate the atmosphere within the pod 14 with the atmosphere within the N 2 purge chamber 24 . The pod 14 is carried among the pod opener 28 , cassette shelf 22 and load/unload stage 18 by the cassette transfer unit 30 . Air cleaned by a clean unit (not shown) provided on the housing 16 is flowed through a space for carrying the pod 14 by the cassette transfer unit 30 .
[0030] Within the N 2 purge chamber 24 , a substrate holder 26 for loading a plurality of substrates 12 in a multistage manner, a substrate alignment device 32 for aligning a notch (or an orientation flat) of the substrate 12 to an optional position, and a substrate transfer unit 34 for carrying the substrate 12 between the pod 14 on the pod opener 28 and the substrate alignment device 32 are provided. A treatment furnace 36 for treating the substrates 12 is provided in an upper part of the N 2 purge chamber 24 , and the substrate holder 26 is loaded into the treatment furnace 36 by a boat elevator 38 as elevating means, or unloaded from the treatment furnace 36 by it. The treatment furnace 36 has a furnace port which is closed by a furnace port shutter 40 during except for a period during treating the substrate 12 .
[0031] Next, operation of the substrate processing equipment 10 according to the embodiment is described.
[0032] First, the pod 14 carried from the outside of the housing 16 by AGV or OHT is set on the load/unload stage 18 . The pod 14 set on the load/unload stage 18 is directly carried onto the pod opener 28 , or stocked temporarily on the cassette shelf 22 and then carried onto the pod opener 28 by the cassette transfer unit 30 . When the pod 14 is carried onto the pod opener 28 , the cap of the pod 14 is removed by the pod opener 28 , and thereby the atmosphere within the pod 14 is communicated with the atmosphere within the N 2 purge chamber 24 .
[0033] Then, a substrate 12 is removed from the pod 14 in a condition of being communicated with the atmosphere within the N 2 purge chamber 24 by the substrate transfer unit 34 . The removed substrate 12 is aligned by the substrate alignment device 32 such that the notch or the orientation flat is fixed in an optional position, and after that carried onto the substrate holder 26 .
[0034] When the substrates 12 have been carried into the substrate holder 26 , the furnace port shutter 40 of the treatment furnace 36 is opened, and then the substrate holder 26 having the substrates 12 mounted therein is loaded into the treatment furnace 36 by the boat elevator 38 .
[0035] After loading, predetermined treatment is performed to the substrates 12 in the treatment furnace 36 , and after the treatment, the substrates 12 and the pod 14 are ejected to the outside of the housing 16 in the reverse order of the above procedure.
[0036] FIG. 3 shows a peripheral configuration of the treatment furnace 36 . The treatment furnace 36 has an outer tube 42 formed from a heat resistant material such as quartz (SiO 2 ). The outer tube 42 is in a cylindrical shape that is closed at an upper end and has an opening at a lower end. An inner tube 44 is disposed concentrically within the outer tube 42 . A heater 46 as heating means is disposed concentrically on the outer circumference of the outer tube 42 . The heater 46 is held on the housing 16 via a heater base 48 .
[0037] As shown in FIG. 4 and FIG. 5 , in the substrate holder 26 , for example, three poles 50 formed from, quartz, silicon carbide and the like are disposed parallel in a vertical direction, and the substrates 12 are held by support slots 52 formed on the poles 50 . The substrate transfer unit 34 has a transfer unit body 54 that moves vertically and rotates, and a main tweezers body 56 that moves reciprocally on the transfer unit body 54 . For example, four tweezers 58 a , 58 b , 58 c and 58 d are fixed to the main tweezers body 56 in a manner of extending parallel to one another. Moreover, sub tweezers body 57 is provided on the transfer unit body 54 such that it can reciprocally move either along with or independently of the main tweezers body 56 . Tweezers 58 e are fixed to the sub tweezers body 57 at a position below the four tweezers 58 a to 58 d and parallel to them. Therefore, as shown in FIG. 4 , the substrate transfer unit 34 can collectively transfer five substrates 12 using the five tweezers 58 a to 58 e , and can transfer one monitor substrate (sheet transfer) using the tweezers 58 e at the lowermost stage. When the monitor substrate is transferred, as shown in FIG. 5 , a space corresponding to one slot is opened between sets of collectively transferred, five substrates 12 , and a monitor substrate 59 is extracted from a pod different from a pod for typical substrates 12 , and inserted between the sets of the five substrates.
[0038] For example, 25 substrates 12 are accommodated in the pod 14 , and in the case that the substrates 12 are transferred into or collected from the substrate holder 26 by the substrate transfer unit 34 , when there is no abnormal substrate in five slots (slot group), five substrates 12 are collectively transferred or collected using the five tweezers 58 a to 58 e , and when there is an abnormal substrate in the slot group, only normal substrates are collected using the tweezers 58 e at the lowermost stage. The monitor substrate may be collected one at a time as in insertion.
[0039] A sensing section 60 as sensing means is provided on the transfer unit body 54 . The sensing section 60 has parallel, two arms 62 a , 62 b , and is provided such that the arms 62 a , 62 b can be turned on a side face of the transfer body 54 . Near front ends of the arms 62 a , 62 b , transmission-type photo-sensors 64 a , 64 b are provided, and one of the photo-sensors is a light emitting element, and the other is a light receiving element. When a holding condition of the substrates 12 transferred into the substrate holder 26 is sensed, the arms 62 a , 62 b are turned and fixed to a side of the substrate holder 26 so that light axes of the photo-sensors 64 a , 64 b run through the substrates 12 , and then sensing output of the photo-sensors 64 a , 64 b is monitored while the substrate transfer unit 34 is moved from a lower end to an upper end of the substrate holder 26 . On the other hand, when the substrates 12 are transferred into the substrate holder 26 by the substrate transfer unit 34 , the arms 62 a , 62 b are turned to a side opposite to the substrate holder side to prevent the arms 62 a , 62 b from being interfered with the substrates 12 or the substrate holder 26 .
[0040] As shown in FIG. 3 , analog signals outputted from the photo-sensors 64 a , 64 b are outputted to a control section 66 including a computer. The control section 66 controls the substrate transfer unit 34 via a driver section 68 such as a motor.
[0041] Next, sensing of the abnormal condition of the substrates 12 is described.
[0042] As shown in FIG. 6( a ), it is assumed that the light emitting element 64 a is situated at the right side, and the light receiving element 64 b is situated at the left side in a view from a top of the substrate holder 26 , and the light emitting element 64 a and the light receiving element 64 b are disposed at a front face side of the substrate holder 26 . As shown in FIG. 6( b ), the substrate 12 may crack while being held in the substrate holder 26 or drop from the support slot 52 of the substrate holder 26 , resulting in falling into abnormal condition. As shown in FIG. 6( c ) and FIG. 6( d ), the abnormal conditions of the substrate 12 are given as follows.
[0043] A. drop/in pairs
[0044] B. drop/light-emitting side drop (left face drop)
[0045] C. drop/light-receiving side drop (right face drop)
[0046] D. drop/rear drop (back face drop)
[0047] E. drop/front drop (front face drop)
[0048] F. cracking/center cracking
[0049] G. cracking/front cracking
[0050] H. cracking/rear cracking
[0051] J. no substrate
[0052] A substrate 12 , which is in the normal condition, is supported parallel to a support slot 52 .
[0053] FIG. 7( a ) shows a relation of signal output from the photo-sensors 64 a , 64 b to the abnormal condition. A positional relation between the substrate holder 26 and the photo-sensors 64 a , 64 b is assumed that the photo-sensors 64 a , 64 b are at a front side, and a side opposed to the photo-sensors is a back side as shown in FIG. 7( b ).
[0054] When the holding condition of the substrates 12 is normal, waveforms outputted from the photo-sensors 64 a , 64 b are regular. For example, when a left or right surface of the substrate 12 drops, sensing waveforms of the photo-sensors 64 a , 64 b are gradually spread at left and right of a peak compared with a normal waveform, consequently width at a reference line is increased. When the substrate 12 completely drops from the support slot 52 , sensing output of the photo-sensors 64 a , 64 b disappears at that support slot 52 from which the substrate has dropped. When the substrate 12 drops from the support slot 52 at the back, the peak is shifted to the upper side compared with the normal waveform. When the substrate 12 drops from the support slot 52 at the front, the peak is shifted to the lower side compared with the normal waveform. The case that the substrate 12 has cracked can be also sensed.
[0055] FIG. 8 shows an example of substrate sensing operation by the control section in a flowchart.
[0056] First, in step S 10 , drive of the substrate transfer unit and the photo-sensors is started. That is, as previously shown in FIG. 3 , the arms 62 a , 62 b are rotationally fixed to the side of the substrate holder 26 , and then a transfer condition of the substrates 12 is sensed by the photo-sensors 64 a , 64 b while the substrate transfer unit 34 is raised from the lowermost end of the substrate holder 26 at a constant speed. The quantity of light of light emitting/receiving of the photo-sensors 64 a , 64 b is inputted into the control section 66 as analog signals.
[0057] In next step S 12 , the analog signals inputted from the photo-sensors 64 a , 64 b are converted into digital signals to analyze detection output from the photo-sensors 64 a , 64 b . In this analysis of output from the photo-sensors 64 a , 64 b , the sensing waveforms from the photo-sensors 64 a , 64 b are recorded and then compared with the normal waveform so that an abnormal slot is specified and thus an abnormal slot list is prepared.
[0058] In next step S 14 , whether before or after heat treatment is determined. When determination is made as before heat treatment, the operation is advanced to step 16 to determine whether an abnormal slot is found or not, and when it is determined that the abnormal slot is not found, the operation is advanced to step S 18 in which the substrate supporter 26 is carried into the treatment furnace 36 , and then heat treatment is carried out. On the other hand, when determination is made as after heat treatment in the step S 14 , or when it is determined in the step S 16 that the abnormal slot is found, the operation is advanced to step S 20 in which collection of the substrates 12 is started. As described before, the collection of the substrates 12 is performed for each of slot groups, and it is begun at a first slot group and ended at a fifth slot group that is a final slot group. In next step S 22 , whether all the five substrates in the slot group to be collected are transferred in the normal condition (not found in the abnormal slot list) is determined. When all the five substrates are determined to be in the normal condition in the step S 22 , the operation is advanced to step S 24 in which all the five substrates are collected together. On the other hand, when it is determined that there is a substrate in the abnormal condition in the five substrates 12 in an objective slot group (found in the abnormal slot list) in the step S 22 , the operation is advanced to step S 26 in which only the substrates in the normal condition are collected in a manner of sheet transfer. When collection is not completed for all the slot groups in the step S 28 , the operation is returned to processing for a next slot group, and when collection is completed for all the slot groups, the operation is finished.
[0059] In the embodiment, when a substrate in the abnormal condition is found, the substrate in the abnormal condition is remained in the substrate holder, and all the substrates in the normal condition are returned into the pod, however, the invention is not necessarily limited to this. When the substrate in the abnormal condition is found, a substrate on or under the substrate may receive a kind of damage. Thus, it is also acceptable that at least one of substrates on and under the substrate in the abnormal condition is also remained in the substrate holder, and other substrates in the normal condition are returned into the pod.
INDUSTRIAL APPLICABILITY
[0060] The invention can be used for substrate treatment equipment that automatically collects substrates.
|
The invention aims to provide substrate treatment equipment that can automatically collect a substrate in a normal condition without needing manual operation. The equipment includes a substrate holder 26 for holding substrates 12 in a multistage manner and a substrate transfer unit 34 for transferring the substrates 12 into the substrate holder 26 , wherein a substrate holding condition of the substrate holder 26 is sensed by a sensing section 60 . The sensing section 60 has photo-sensors 64 a , 64 b , and sensing waveforms sensed by the photo-sensors 64 a , 64 b are compared with a normal waveform. A control section 66 is provided, which controls a substrate transfer unit 34 such that substrates 12 other than at least a substrate 12 that was determined to be abnormal are transferred by the unit.
| 8
|
RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a process for the preparation of synthesis gas (“syngas”), i.e., a mixture of carbon monoxide and hydrogen, from natural gas. More particularly, the present invention relates to controlling the exit stream composition of a syngas reactor by controlling the feed hydrocarbon composition.
BACKGROUND
Large quantities of methane, the main component of natural gas, are available in many areas of the world. However, a significant portion of that natural gas is situated in areas that are geographically remote from population and industrial centers (“stranded gas”). The costs of compression, transportation, and storage often makes the use of stranded gas economically unattractive. Consequently, the stranded natural gas is often flared. Flaring not only wastes the energy content and any possible economic value the natural gas may have but may also create environmental concerns.
To improve the economics of natural gas transportation and utilization, much research has focused on using the methane component of natural gas as a starting material for the production of higher hydrocarbons and hydrocarbon liquids. The conversion of methane to higher hydrocarbons is typically carried out in two steps. In the first step, methane is reacted to produce carbon monoxide and hydrogen (i.e., synthesis gas or “syngas”). In a second step, the syngas is converted to higher hydrocarbon products by processes such as Fischer-Tropsch synthesis. For example, fuels with boiling points in the middle distillate range, such as kerosene and diesel fuel, and hydrocarbon waxes may be produced from the syngas. In addition, syngas may be used for the manufacture of ammonia, hydrogen, methanol, and other chemicals. Less traditional uses of syngas continue to be developed and have increased in importance in recent years, such as in the production of acetic acid and acetic anhydride manufacture. Among the promising new developments in syngas chemistry are routes to ethylene.
There are currently three primary methods for converting methane to syngas. Those methods include: steam reforming (the most widespread), dry reforming (also called CO 2 reforming), and partial oxidation. Steam reforming, dry reforming, and partial oxidation ideally proceed according to the following reactions respectively:
CH 4 +H 2 O+heat→CO+3H 2 (1)
CH 4 +CO 2 +heat→2CO+2H 2 (2)
CH 4 +½O 2 →CO+2H 2 +heat (3)
For a general discussion of steam reforming, dry (or CO 2 ) reforming, and partial oxidation, please refer to HAROLD GUNARDSON, Industrial Gases in Petrochemical Processing 41-80 (1998), the contents of which are incorporated herein by reference.
Although a theoretical H 2 :CO ratio can be calculated for any given reaction, relative amounts of hydrogen and carbon in a syngas product stream depend on many factors including the type of reaction, the process technology, the feedstock composition, and the reactor operating conditions. The theoretical ratio of hydrogen to carbon monoxide in the reactant stream of reactions 1, 2, and 3 can easily be calculated as 3:1, 2:2 (i.e., 1:1), and 2:1. The actual ratio of hydrogen to carbon monoxide in syngas product streams can range as low as 0.6 with CO 2 reforming of natural gas or partial oxidation of petroleum coke to as high as 6.5 with steam methane reforming. In addition, it has been noticed in GUNARDSON on pages 68-71 the actual molar ratio of H 2 :CO in the product stream can vary depending upon the feedstock used.
There are many processes, such as the production of methanol, in which an H 2 :CO molar ratio of about 2:1 is desired. There are also processes in which a molar ratio of hydrogen and carbon monoxide of less than 2:1 is preferable. One such process is hydroformylation, which is the addition of one molecule of carbon monoxide and one molecule of hydrogen to an olefin to make an aldehyde. The following reaction illustrates one of the simplest examples of hydroformylation:
C 2 H 4 +CO+H 2 →CH 3 CH 2 CHO (4)
Hydroformylation is, inter alia, an intermediate step in both methyl methacrylate synthesis and the oxo process to produce alcohols. Additionally, there may be other processes in which an H 2 :CO ratio of between 2:1 and about 1:1 is desirable.
As noted above, one method of producing syngas with a molar ratio of hydrogen to carbon monoxide of between about 2:1 and about 1:1 is by the partial oxidation of methane followed by the CO 2 reforming of methane. Unfortunately, CO 2 reforming is endothermic and requires external heating to drive the reaction, which increases the capital cost of CO 2 reforming. In addition, this scheme of partial oxidation followed by CO 2 reforming requires two reactors thereby also increasing the capital cost. Thus, in many situations, partial oxidation followed by CO 2 reforming may be economically or physically (or both) unfeasible or undesirable.
There is, therefore, a need for a less capital intensive process in which the H 2 :CO molar ratio in the product stream can be varied and controlled between about 2:1 and about 1:1
SUMMARY OF THE PREFERRED EMBODIMENTS
The present invention provides a method for controlling the H 2 :CO molar ratio between about 2:1 and about 1:1 in a syngas product stream by controlling the feed hydrocarbon composition.
An embodiment of the present method generally includes predetermining a desired syngas product stream H 2 :CO molar ratio, selecting a hydrocarbon with an actual natural H 2 :CO molar ratio greater than the desired molar ratio, selecting a hydrocarbon with an actual natural H 2 :CO molar ratio less than the desired molar ratio, mixing the two hydrocarbons on-line such that the actual natural H 2 :CO molar ratio of the mixture is equal to the desired molar ratio, and net catalytically partially oxidizing the mixture to produce syngas with the desired H 2 :CO molar ratio.
It is also possible to control and vary the product stream composition by controlling and varying the feed stream composition.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more detailed understanding of the present invention, reference is made to the accompanying FIGURE, which is a schematic cross sectional view of a first preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred reactor is a standard catalytic partial oxidation (“CPOX”) reactor 90 comprising a refractory lining 20 and a CPOX catalyst system 10 . The reactants for reactor 90 comprise oxygen-containing stream 40 and hydrocarbon feedstreams 70 and 80 which are combined to become feedstream 30 . Streams 30 and 40 are mixed to become stream 50 which is introduced to catalyst system 10 . After reacting in catalyst system 10 , the stream exits reactor 90 as product stream 60 . Definitions of terms of art used in this Detailed Description (e.g., “ideal natural H 2 :CO ratio”) are defined at the end of this Detailed Description.
Referring now to the catalyst system 10 , any of a variety of well known catalysts containing various metals such as, by way of example only, Group VIII metals, iron, cobalt, nickel, ruthenium, rhodium, palladium, iridium, platinum, cerium, samarium, or combinations thereof may be used. These catalysts may be supported on a variety of supports such as, by way of example only, alumina, silica, magnesia, zirconia, yttria, calcium oxide, zinc ozide, perovskites, lanthanide oxides, partially stabilized zirconia, or combinations thereof. The catalyst supports may be configured in several ways as are known in the art such as, by way of example only, monoliths, pellets, pills, spheres, granules, gauze, particulates, beads, rings, or ceramic honeycomb structures or any other support as is known in the art. Preferably, gas hourly space velocity of the feed stream is great enough and the catalyst bed length is short enough such that the contact time of the feed stream with the catalyst is no more than about 200 ms or optionally, no more than about 10 ms. The bed length is preferably at least about ⅛ inch long and the gas hourly space velocity of feed gas across the bed is preferably about 1,000-10,000,000 NL/kg/hr, and more preferably about 20,000-6,000,000 NL/kg/hr.
In operation, the desired H 2 :CO molar ratio for product stream 60 is predetermined for maximization of a downstream process (not shown). For purposes of this example only, the predetermined ratio will be 1.75:1. This desired ratio is achieved by controlling the composition of the feed stream 50 which in turn is achieved by controlling the composition and relative flow of hydrocarbon feed streams 70 and 80 .
For purposes of this example and for simplicity's sake, ideal (rather than actual) natural H 2 :CO ratios will be used for the hydrocarbon feed streams. It should be understood that in actual operation, the actual natural H 2 :CO ratios for the actual reactor conditions should be used. It should also be understood that although the following calculations are done with pure feed streams, diluted feed streams may be used. If diluted feed streams are used, one of ordinary skill in the art can easily modify the flow rate of the diluted streams so that the amounts of the reactant hydrocarbons in the feed streams create the proper relative reactant gas proportions in the mixed feed stream.
In accordance with one embodiment of the present invention, hydrocarbon feed stream 70 is chosen to be methane CH 4 because its ideal natural H 2 :CO ratio for CPOX is 2:1 (greater than the predetermined desired ratio). Hydrocarbon feed stream 80 is chosen to be ethane because its ideal natural H 2 :CO ratio for CPOX is 1.5:1 (less than the predetermined desired ratio). Determining the proper relative flows of hydrocarbon feed streams 70 and 80 is done by adjusting the relative flows such that the weighted average of the ideal natural H 2 :CO ratios is equal to the desired ratio. For a binary mixture such as this one (of methane and ethane), the proper ratio can be calculated by solving the following set of equations for x and y where C equals the desired H 2 :CO ratio, A equals the natural H 2 :CO ratio of stream 70 (e.g., 2), B equals the natural H 2 :CO ratio of stream 80 (e.g., 1.5), x equals the percentage of the total combined molar flow of streams 70 and 80 of the component of stream 70 , and y equals the percentage of the total combined molar flow of streams 70 and 80 of the component of stream 80 :
Ax+By=C (5)
x+y= 1 (6)
Solving Equations 5 and 6 for x and y for the current example, x=0.5 and y=0.5. Thus, in this example stream 70 and stream 80 should each have 50% of the combined molar flow of the two streams ( 70 plus 80 ). (i.e., both streams 70 and 80 should have equal molar flow rates of methane and ethane respectively).
The two feed streams 70 and 80 are then fed, along with oxygen containing stream 40 , into a syngas reactor 90 . The oxygen containing stream 40 is preferably substantially pure oxygen, but it may also comprise air or oxygen-enriched air.
In situations where there are greater than two hydrocarbon feed streams, the relative molar flow rates of the plurality of streams needed to achieve the desired product stream H 2 :CO molar ratio can be calculated by solving the following set of equations for x 1 , x 2 , . . . x n .
A 1 x 1 +A 2 x 2 +. . . A n x n =C (7)
x 1 +x 2 +. . . x n =1 (8)
In Equations 6 and 7, n is the number of hydrocarbon feed streams, A 1 , A 2 , . . . A n are the natural H 2 :CO ratios of the corresponding hydrocarbon feed streams, x 1 , x 2 . . . x n are the percentages of each respective hydrocarbon flow, and C is the desired product stream H 2 :CO molar ratio. Unless there are other constraints, there will be multiple solutions to these equations. However, one of ordinary skill in the art can easily determine an acceptable ratio of hydrocarbon feeds based on factors such as, for example, feed cost, feed availability, and environmental concerns.
It was found that with a propane-oxygen feedstream, syngas was generated in high selectivity, with a small amount of CO 2 . The operation was stable and H 2 :CO ratio was about 1.3:1. With a methane-oxygen feed stream, these catalysts yield syngas with low CO 2 selectivity and H 2 :CO ratio of about 1.8-2:1. From these observations, it is proposed that by varying and controlling the hydrocarbon composition in the feed, the H 2 :CO ratio in the syngas product can be modified based on the desired use of the syngas. By using a selective and stable catalyst for syngas generation from a variety of hydrocarbons, a single-stage process can be designed for obtaining syngas with a H 2 :CO ratio less than 2:1.
It is contemplated that in some instances it may happen that the actual natural H 2 :CO ratio of a mixture may not equal the molar weighted average of the actual natural H 2 :CO ratios of the components of the mixture due to differences in the chemical behavior of the mixture from the individual components. In this instance, the flow of the feed components can be adjusted to reach the desired H 2 :CO ratio in the product stream. For example, if the actual H 2 :CO ratio in the product stream is greater than desired, increasing the relative amount of the feed components with lower actual natural H 2 :CO ratio should decrease the observed product stream H 2 :CO ratio. The opposite should also be true (i.e., to raise the product stream H 2 :CO ratio, increase the relative proportion of the higher actual natural H 2 :CO ratio feed components).
EXAMPLES
Example 1
CPOX with Rh/Yb Catalyst
Procedure for Preparation of Rh/Yb/ZrO 2 Catalysts
The Rh-Yb catalyst supported on Zirconia granules can be prepared according to the following procedure, given here for laboratory-scale batches:
1. Dissolve 0.5476 grams of Yb(NO 3 ) 3 .5H 2 O in 3 grams of distilled and de-ionized (DDI) water at about 70° C. on the hotplate. Add this solution to ZrO 2 granules (35-50 mesh, 10.20 grams, 1100° C.-calcined).
2. Dry the material at about 70° C. for 1 hour and calcine in air according to the following schedule: 5° C./min ramp up to 125° C.; hold at 125° C. for 1 hour; 5° C./min ramp up to 400° C.; hold at 400° C. for 1 hour; 5° C./min ramp up to 800° C.; hold at 800° C. for 1 hour; 5° C./min ramp up to 1000° C.; hold at 1000° C. for 3 hours; 10° C./min ramp down to room temperature.
3. The above procedure should result in 2 wt % Yb based on the weight of ZrO 2 granules.
4. Dissolve 0.9947 grams of RhCl 3 .xH 2 O in 3 grams of DDI water at about 60° C. and add to the Yb 2 O 3 -coated ZrO 2 granules at about 70° C.
5. Dry the material at about 70° C. for 1 hour and calcine in air according to the following schedule: 5° C./min ramp up to 125° C.; hold at 125° C. for 1 hour; 5° C./min ramp up to 400° C.; hold at 400° C. for 1 hour; 5° C./min ramp up to 800° C.; hold at 800° C. for 1 hour; 5° C./min ramp up to 1000° C.; hold at 1000° C. for 3 hours; 10° C./min ramp down to room temperature.
6. The above procedure should result in 4 wt % Rh based on the weight of ZrO 2 granules.
7. Reduce the catalyst with H 2 using 1:1 by volume flow of N 2 :H 2 mixture at 0.3 standard liter per minute (SLPM) measured at 0° C. and 1 atm pressure, using the following schedule: 3° C./min ramp up to 125° C.; hold at 125° C. for 0.5 hour; 3° C./min ramp up to 500° C.; hold at 500° C. for 3 hours; 5° C./min ramp down to room temperature.
Test Procedure
The partial oxidation reactions are carried out in a conventional flow apparatus using a 44 mm O.D.×38 mm I.D. quartz insert embedded inside a refractory-lined steel vessel. The quartz insert contains a catalyst bed containing the Rh/Yb/ZrO 2 catalyst as prepared above. Preheating the hydrocarbon feed that flows through the catalyst bed provides the heat needed to initiate the reaction. Oxygen is mixed with the hydrocarbon feed stream immediately before the mixture enters the catalyst bed. Once the reaction is initiated, it proceeded autothermally. Two thermocouples with ceramic sheaths are used to measure catalyst inlet and outlet temperatures. The molar ratio of feed hydrocarbon to O 2 is generally about 2:1, however the relative amounts of the gases, the catalyst inlet temperature and the reactant gas pressure can be varied by the operator according to the parameters being evaluated (see the following Tables). The product gas mixture is analyzed for the feed hydrocarbons, O 2 , CO, H 2 , CO 2 and N 2 using a gas chromatograph equipped with a thermal conductivity detector. A gas chromatograph equipped with a flame ionization detector analyzes the gas mixture for CH 4 , C 2 H 6 , C 2 H 4 and C 2 H 2 . The feed hydrocarbon conversion levels and the CO and H 2 product selectivities obtained are considered predictive of the conversion and selectivities that will be obtained when the same catalyst is employed in a commercial scale reactor under similar conditions of reactant concentrations, temperature, reactant gas pressure and space velocity.
The following test data were obtained at a total feed flowrate of 3.5 SLPM at a preheat temperature of 3000° C. and hydrocarbon:oxygen molar ratio of 2:1.
Feed Hydrocarbons
Feed molar ratio
H2:CO molar ratio
CH 4
CH 4 :O 2 = 2:1
2.04
CH 4 ,C 2 H 6
CH 4 :C 2 H 6 :O 2 = 1:1:1
1.74
C 2 H 6
C 2 H 6 :O 2 = 2:1
1.67
C 2 H 6 , C 3 H 8
C 2 H 6 :C 3 H 8 :O 2 = 1:1:1
1.56
CH 4 , C 3 H 8
CH 4 :C 3 H 8 :O 2 = 1:1:1
1.50
C 3 H 8
C 3 H 8 :O 2 = 2:1
1.46
The results shown above clearly indicate the effect of feed hydrocarbon composition on the product hydrocarbon:carbon monoxide ratio (referred to as ‘syngas ratio’). By mixing hydrocarbons with different carbon numbers, a wide range of syngas ratios can be obtained, without modifying the process conditions. All of the above reactions occur under the same preheat temperature range, flow rates and heat transfer rates, so there is no need for design changes.
For purposes of this specification, the following definitions shall apply.
The term “catalyst system” as used herein means any acceptable system for catalyzing the desired reaction in the reaction zone. By way of example only, the catalyst system of a syngas steam reforming reaction usually includes a support and a catalyst. Acceptable supports include, for example, particulates, pills, beads, granules, pellets, monoliths, ceramic honeycomb structures, wire gauze, or any other suitable supports such as those listed herein. Likewise, The catalyst may be selected from the group consisting of nickel, samarium, rhodium, cobalt, platinum, rhodium-samarium, platinum-rhodium Ni—MgO, combinations thereof, or any other catalysts as is well known in the art such as those cited herein. The above-exemplified examples of supports and catalysts are only examples. There are a plethora of catalysts systems known in the art which would be acceptable and are contemplated to fall within the scope, such as those disclosed in STRUCTURED CATALYSTS AND REACTORS 179-208, 599-615 (Andrzej Cybulski and Jacob A. Moulijn eds. 1998) incorporated herein by reference for all purposes.
The term “natural H 2 :CO ratio” shall mean the H 2 :CO ratio expected to be present in the product stream of the net partial oxidation of a feed stream.
The “ideal natural H 2 :CO ratio” is the H 2 :CO ratio predicted by the basic partial oxidation reaction. For example, the basic partial oxidation reaction for methane (CH 4 ) is:
CH 4 +½O 2 →CO+2H 2 (3)
The H 2 :CO ratio in the product of that reaction is 2:1. The generalized partial oxidation reaction for alkanes is:
C n H (2n+2) +(n/2)O 2 →n CO+(n+1)H 2 (9)
Thus, the ideal natural H 2 :CO ratio of an alkane is [(n+1)/n]:1. The reaction for the partial oxidation of any hydrocarbon consisting of only carbon and hydrogen (e.g., isobutane) can easily be determined by one of ordinary skill in the art by balancing the equation:
a HC+ b O 2 →c CO+ d H 2 (10)
where HC is the molecular formula of the hydrocarbon and a, b, c, and d are the stoichiometric coefficients that balance the equation. In Equation 10, the ideal natural H 2 :CO ratio for HC is (d/c): 1.
The “actual natural H 2 :CO ratio” of a feed stream is the H 2 :CO ratio observed in the product stream of the net partial oxidation of a given feed stream under given reactor conditions. It may differ from the ideal natural H 2 :CO ratio because of side reactions or adverse reactor conditions. For example, the actual natural H 2 :CO ratio of a methane feed is often measured to be approximately 1.8:1 due to the existence of secondary reactions and may vary with variations in reactor conditions and catalyst systems. While the example discussed above uses the ideal natural H 2 :CO ratios for methane and ethane for the calculation, the calculations are performed exactly the same using the actual natural H 2 :CO ratio (i.e., the H 2 :CO ratio of the product stream is controlled by controlling the weighted average of the actual natural H 2 :CO ratios of the hydrocarbon feed streams).
For the purposes of this disclosure, the term “net partial oxidation reaction” means that the partial oxidation reaction shown in Equation (3), above, predominates. However, other reactions such as steam reforming (Equation 1), dry reforming (Equation (2)) and/or water-gas shift (Equation (11)) may also occur to a lesser extent.
CH 4 +CO 2 ⇄2CO+2H 2 (2)
CO+H 2 O⇄CO 2 +H 2 (11)
The actual natural H 2 :CO ratio resulting from the catalytic net partial oxidation of the methane, or natural gas, and oxygen feed mixture is about 2:1, similar to the ideal natural H 2 :CO ratio of Equation (3).
Without further elaboration, it is believed that one skilled in the art can, using the description herein, utilize the present invention to its fullest extent. The embodiments herein are to be construed as illustrative, and not as constraining the remainder of the disclosure in any way whatsoever.
|
A method for generating syngas having a H 2 :CO ratio of less than 2:1 including selecting a predetermined desired syngas H 2 :CO molar ratio, selecting a hydrocarbon with a natural H 2 :CO molar ratio less than the desired ratio, selecting a hydrocarbon with a natural H 2 :CO molar ratio greater than the desired ratio, mixing the two hydrocarbons such that the natural H 2 :CO molar ratio of the mixture is the desired ratio, and catalytically partially oxidizing the mixture to produce syngas with the desired ratio.
| 2
|
TECHNICAL FIELD
This technology generally relates to managing user information and, more particularly, to methods for securing user information using a unique per-client one-time use cryptographic key for securing client's information thereof.
BACKGROUND
Client information generally relates to confidential information of clients such as user name, passwords, bank account details, client cookies etc. This confidential information is often stored in a server of the service provider and the service provider needs to ensure that confidential information of the clients/customers are not stolen or misused. Accordingly, there is a need to protect this confidential information.
In the existing solutions, there is an encryption/decryption key stored at the server which is used to encrypt/decrypt the client information securely. Since this is already present in the server, it would not provide the best security as a third party can hack or steal the encryption/decryption key and then has access to all the confidential information. Also, when the access to the server is compromised or if the server memory is dumped as part of process cores, secure information pertaining to various clients/customers might also be retrieved.
SUMMARY
A method for managing user information comprises obtaining by the application manager computing device at least one cryptographic key from a request by a client computing device. The application manager computing device encrypts or decrypts user information corresponding to a user using the cryptographic key. The application manager computing device authenticates the request based on the encryption or decryption of the user information. The cryptographic key is deleted by the application manager computing device after the completion of the user session.
A non-transitory computer readable medium having stored thereon instructions for managing user information comprising machine executable code which when executed by at least one processor, causes the processor to perform steps comprising obtaining at least one cryptographic key from a request by a client computing device for a user session. User information corresponding to a user is encrypted or decrypted using the cryptographic key. The request is authenticated based on encryption or decryption of the user information. The cryptographic key is deleted after the completion or termination of the user session.
An application manager computing device including one or more processors, a memory coupled to the one or more processors, and a configurable logic unit coupled to the one or more processors and the memory via at least one bus, at least one of the configurable logic unit configured to implement and the one or more processors configured to execute programmed instructions stored in the memory includes obtaining at least one cryptographic key from a request sent by a client computing device. User information corresponding to a user is encrypted or decrypted using the at least one cryptographic key. The request is authenticated based on encryption or decryption. The at least one cryptographic key is deleted after the completion or termination of a new user session.
This technology provides a number of advantages including providing more effective methods, non-transitory computer readable medium and devices for securing user information. This exemplary technology makes managing user information more secure by storing the cryptographic key used for encrypting user's sensitive information in a location that is different from the location of the encrypted user's sensitive information itself.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of an exemplary network environment with an application manager computing device for managing user information;
FIGS. 2 a - 2 b are flowcharts of an exemplary method for managing user information.
DETAILED DESCRIPTION
An exemplary network environment 10 with an application manager computing device 14 for managing user information to a service is illustrated in FIG. 1 . The exemplary environment 10 includes client computing devices 12 , the application manager computing device 14 , servers 16 and user information server 17 which are coupled together by local area networks (LANs) 28 and wide area network (WAN) 30 , although the environment can include other types and numbers of devices, components, elements and communication networks in other topologies and deployments. While not shown, the exemplary environment 10 may include additional network components, such as routers, switches and other devices, which are well known to those of ordinary skill in the art and thus will not be described here. This technology provides a number of advantages including providing more effective methods, non-transitory computer readable medium and devices for securing user information.
Referring more specifically to FIG. 1 , application manager computing device 14 is coupled to client computing devices 12 through one of the LANs 28 and WAN 30 , although the client computing devices 12 and application manager computing device 14 may be coupled together via other topologies. Additionally, the application manager computing device 14 is coupled to the servers 16 through the WAN 30 and another one of the LANs 28 , although the servers 16 and application manager computing device 14 may be coupled together via other topologies. The application manager computing device 14 also is coupled to the user information server 17 through the WAN 30 , although the application manager computing device 14 and the user information server 17 may be coupled together via other topologies.
The application manager computing device 14 assists with managing user information as illustrated and described with the examples herein, although application manager computing device 14 may perform other types and numbers of functions. The application manager computing device 14 includes at least one processor 18 , memory 20 , optional configurable logic device 21 , input and display devices 22 , and interface device 24 which are coupled together by bus 26 , although application manager computing device 14 may comprise other types and numbers of elements in other configurations.
Processor(s) 18 may execute one or more computer-executable instructions stored in the memory 20 for the methods illustrated and described with reference to the examples herein, although the processor(s) can execute other types and numbers of instructions and perform other types and numbers of operations. The processor(s) 18 may comprise one or more central processing units (“CPUs”) or general purpose processors with one or more processing cores, such as AMD® processor(s), although other types of processor(s) could be used (e.g., Intel®).
Memory 20 may comprise one or more tangible storage media, such as RAM, ROM, flash memory, CD-ROM, floppy disk, hard disk drive(s), solid state memory, DVD, or any other memory storage types or devices, including combinations thereof, which are known to those of ordinary skill in the art. Memory 20 may store one or more non-transitory computer-readable instructions of this technology as illustrated and described with reference to the examples herein that may be executed by the one or more processor(s) 18 . The flow chart shown in FIG. 2 a and FIG. 2 b is representative of example steps or actions of this technology that may be embodied or expressed as one or more non-transitory computer or machine readable instructions stored in memory 20 that may be executed by the processor(s) 18 and/or may be implemented by configured logic in the optional configurable logic device 21 .
The configurable logic device 21 may comprise specialized hardware configured to implement one or more steps of this technology as illustrated and described with reference to the examples herein. By way of example only, the optional configurable logic device 21 may comprise one or more of field programmable gate arrays (“FPGAs”), field programmable logic devices (“FPLDs”), application specific integrated circuits (ASICs”) and/or programmable logic units (“PLUs”).
Input and display devices 22 enable a user, such as an administrator, to interact with the application manager computing device 14 , such as to input and/or view data and/or to configure, program and/or operate it by way of example only. Input devices may include a keyboard and/or a computer mouse and display devices may include a computer monitor, although other types and numbers of input devices and display devices could be used.
The interface device 24 in the application manager computing device 14 is used to operatively couple and communicate between the application manager computing device 14 and the client computing devices 12 and the servers 16 which are all coupled together by one or more of the local area networks (LAN) 28 and/or the wide area network (WAN) 30 , although other types and numbers of communication networks or systems with other types and numbers of connections and configurations to other devices and elements. By way of example only, the local area networks (LAN) 28 and the wide area network (WAN) 30 can use TCP/IP over Ethernet and industry-standard protocols, including NFS, CIFS, SOAP, XML, LDAP, and SNMP, although other types and numbers of communication networks, can be used. In this example, the bus 26 is a hyper-transport bus in this example, although other bus types and links may be used, such as PCI.
Each of the client computing devices 12 , servers 16 and the user information server 17 include a central processing unit (CPU) or processor, a memory, an interface device, and an I/O system, which are coupled together by a bus or other link, although other numbers and types of network devices could be used. The client computing devices 12 , in this example, may run interface applications, such as Web browsers, that may provide an interface to make requests for and send content and/or data to different server based applications at servers 16 via the LANs 28 and/or WANs 30 . Additionally, in order for the client computing devices 12 to requests for content to one or more of the servers 16 , each client computing device 12 may have to provide one or more user credential information for authentication.
Generally, servers 16 process requests received from requesting client computing devices 12 via LANs 28 and/or WANs 30 according to the HTTP-based application RFC protocol or the CIFS or NFS protocol in this example, but the principles discussed herein are not limited to this example and can include other application protocols. A series of applications may run on the servers 16 that allow the transmission of data, such as a data file or metadata, requested by the client computing devices 12 . The servers 16 may provide data or receive data in response to requests directed toward the respective applications on the servers 16 from the client computing devices 12 . It is to be understood that the servers 16 may be hardware or software or may represent a system with multiple servers 16 , which may include internal or external networks. In this example the servers 16 may be any version of Microsoft® IIS servers or Apache® servers, although other types of servers may be used. Further, additional servers may be coupled to the LAN 28 and many different types of applications may be available on servers coupled to the LAN 28 .
In this example, the exemplary environment 10 includes user information server 17 . The user information server 17 receives the request from the application manager computing device 14 via WAN 30 according to the HTTP-based application RFC protocol or the CIFS or NFS protocol in this example, but the principles discussed herein are not limited to this example and can include other application protocols. One or more user related information such as user name, password may reside in the user information server 17 , although other types of user related information may also be present in the user information server 17 . The user information server 17 may provide data in the form of encrypted/decrypted user information corresponding to a user in response to requests directed toward the user information server 17 , although other types of information may also be provided. It is to be understood that the user information server 17 may be hardware or software.
Although an exemplary network environment 10 with the client computing devices 12 , the application manager computing device 14 , servers 16 , the LANs 28 and the WAN 30 are described and illustrated herein, other types and numbers of systems, devices, blades, components, and elements in other topologies can be used. It is to be understood that the systems of the examples described herein are for exemplary purposes, as many variations of the specific hardware and software used to implement the examples are possible, as will be appreciated by those skilled in the relevant art(s).
Additionally, in this example, a user session is established between the application manager computing device 14 and the requesting client computing device 12 through one or more of LANs 28 and/or WANs 30 . The session may be a semi-permanent interactive information exchange between the application manager computing device 14 and the client computing devices 12 which has sent the request for authentication. The user session may be established at a certain point of time and may also be terminated at a later point of time. An established communication session may involve more than one message exchanged between the application manager computing device 14 and the client computing devices 12 . Further, the session may also be a stateless communication wherein an independent request may be received only once by the application manager computing device 14 and the application manager computing device 14 may need to respond only once.
Furthermore, each of the systems of the examples may be conveniently implemented using one or more general purpose computer systems, microprocessors, digital signal processors, and micro-controllers, programmed according to the teachings of the examples, as described and illustrated herein, and as will be appreciated by those of ordinary skill in the art.
In addition, two or more computing systems or devices can be substituted for any one of the systems or devices in any example. Accordingly, principles and advantages of distributed processing, such as redundancy and replication also can be implemented, as desired, to increase the robustness and performance of the devices and systems of the examples. The examples may also be implemented on computer system(s) that extend across any suitable network using any suitable interface mechanisms and traffic technologies, including by way of example only teletraffic in any suitable form (e.g., voice and modem), wireless traffic media, wireless traffic networks, cellular traffic networks, G3 traffic networks, Public Switched Telephone Network (PSTNs), Packet Data Networks (PDNs), the Internet, intranets, and combinations thereof.
The examples may also be embodied as a non-transitory computer readable medium having instructions stored thereon for one or more aspects of the technology as described and illustrated by way of the examples herein, which when executed by a processor (or configurable hardware), cause the processor to carry out the steps necessary to implement the methods of the examples, as described and illustrated herein.
An exemplary method for managing user information to a service will now be described with reference to FIGS. 1 , 2 a - 2 b . In step 201 , the application manager computing device 14 receives a request from a client computing device 14 , although the application manager computing device 14 may receive additional information such as client/user credentials from the client computing device 12 .
In step 202 , the application manager computing device 14 verifies and validates the client credentials from the requesting one of the client computing devices 12 using session validation logic, although other types of session validation algorithms may also be used. The validation of the session identification information is performed only when the new user session has been created by the application manager computing device 14 . If in step 202 the session identification information is not verified, then the No branch is taken to step 250 where this exemplary process ends. If in step 210 the session identification information is verified, then the Yes branch is taken to step 203 .
In step 203 , the application manager computing device 14 checks if the requested is associated with a new user session or an already existing session based on the a session identification information and/or a cryptographic key. If the application manager computing device 14 determines that it is a new user session, a Yes branch is taken to step 204 , else a No branch is taken to step 215 .
In step 204 , the application manager computing device 14 creates a new user session with session identification information and a new at least one cryptographic key. In another exemplary method, the new at least one cryptographic key or an attribute of the cryptographic key can be used as a session identification information.
In step 205 , the application manager computing device 14 a new session state for the requesting client computing device 12 is allocated.
In step 206 , the application manager computing device 14 calculates a one-way hash value of the cryptographic key, although other types of functions can be calculated. The hash value can be used by the application manager computing device 14 to identify the session state allocated on the application manager computing device.
In step 207 , the application manager computing device 14 stores the user information along with the cryptographic key in the newly created session state for the client computing device 12 , although the user information and the cryptographic key can also be stored in the memory 20 of the application manager computing device 14 .
In step 208 , the application manager computing device 14 associates the session state with the one-way hash value of the cryptographic key, this association is used by application manager computing device to select the session state whenever it needs to access the client's information pertaining to a client. Based on the cryptographic key retrieved from the client, application manager computing device can retrieve the associated session state, although other types and numbers of states and other values can be associated.
In step 209 , the application manager computing device 14 transmits the cryptographic key and the session identification information back to the requesting one of the client computing devices 12 for storage, although parts or the entire cryptographic key could be stored in other manners. By way of example, the cryptographic key may be split by the application manager computing device 14 and at least one part of the cryptographic key may be stored in the memory of the requesting one of the client computing devices 12 and the other parts may be stored at other locations. The application manager computing device 14 keeps track of the cryptographic key stored at different locations by storing the location information in the session state. An appropriate session state is used to store the keys location information by selecting a session state based on the hash of the cryptographic key.
Further, in another example the application manager computing device 14 may store the cryptographic key in a different location and may send the address of the location to the requesting one of the client computing devices 12 . Further, the session identification information and/or the cryptographic key may be stored in the requesting one of the client computing devices 12 as a cookie. The cryptographic key created by the application manager computing device 14 is used to securely encrypt user sensitive information such as user name, password etc.
With reference to FIG. 2 b , in step 215 , the application manager computing device 14 determines if the cryptographic key is present in the request sent by the client computing device 12 . If in step 215 the application manager computing device 14 determines that the entire cryptographic key is present in the request sent by the client computing device 12 , it extracts the cryptographic key and takes the Yes branch to step 240 . Further, the application manager computing device 14 on extracting, caches the cryptographic key for processing the subsequent request, although the cryptographic key could be obtained and stored in other manners.
If in step 215 the application manager computing device 14 determines that the entire cryptographic key is not present in the request sent by the client computing device 12 , the No branch is taken to step 220 . In step 220 , the application manager computing device 14 checks if the obtained cryptographic key was split into a plurality of parts with one part in the current request. If in step 220 the application manager computing device determines that the cryptographic key was split into a plurality of parts with one part in the current request, then the Yes branch is taken to step 225 .
In step 225 , the application manager computing device 14 retrieves the one part of the cryptographic key from the current request sent from the client computing device 12 and the other missing parts of the cryptographic key from one or more other locations by retrieving the list of locations from session state, although other manners for splitting and then retrieving the parts of the cryptographic key can be used. For example, the application manager computing device 14 may only retrieve a subset of the other missing parts from the one or more locations or could retrieve all of the missing parts from different locations. An appropriate session state is selected by using the hash of cryptographic key and proceeds to step 240 .
If back in step 220 the application manager computing device determines that the cryptographic key was not split into a plurality of parts with one part in the current request, then the No branch is taken to step 230 . In step 230 , the application manager computing device 14 determines if the cryptographic key is stored in a different location. If in step 230 , the application manager computing device 14 determines the cryptographic key is not stored in a different location, then the No branch is taken to step 250 to end the process.
If in step 230 , the application manager computing device 14 determines the cryptographic key is stored in a different location, then the Yes branch is taken to step 235 . In step 235 , the application manager computing device 14 obtains the cryptographic key from the location based on the address retrieved from the request sent by the client computing device 12 .
In step 240 , the application manager computing device 14 obtains the user information from the user information server 17 based on the received request and decrypts or encrypts the user information present in the user information server 17 with the at least one unique cryptographic key. Additionally, the application manager computing device 14 may decrypt the user information corresponding to a user and authenticate a request sent to the server 16 on behalf of the client computing device 12 . Further, the application manager computing device 14 after providing authentication may encrypt the user information in the user information server to store it securely.
Proceeding to step 245 , the application manager computing device 14 deletes the cached cryptographic key after the request has been serviced or if the new user session has been terminated and the process ends at step 250 .
In the above disclosed example, the secure storage of user/client information acts as a per-client secure vault which is only accessible of the client computing device 12 if it has passed the session identification information validation and has the cryptographic key. Additionally, for each new user session a new cryptographic key is generated making this per-client secure vault to be one-time use only. Further, a second cryptographic key may also be generated and stored by the application manager computing device 14 within the new user session. Accordingly, as illustrated and described with references to the examples herein, this technology makes managing user information both secure and efficient.
Having thus described the basic concept of the invention, it will be rather apparent to those skilled in the art that the foregoing detailed disclosure is intended to be presented by way of example only, and is not limiting. Various alterations, improvements, and modifications will occur and are intended to those skilled in the art, though not expressly stated herein. These alterations, improvements, and modifications are intended to be suggested hereby, and are within the spirit and scope of the invention. Additionally, the recited order of processing elements or sequences, or the use of numbers, letters, or other designations therefore, is not intended to limit the claimed processes to any order except as may be specified in the claims. Accordingly, the invention is limited only by the following claims and equivalents thereto.
|
A method, non-transitory computer readable medium and application manager computing device comprises obtaining at least one cryptographic key from a request by a client computing device for a user session. User information corresponding to a user is encrypted or decrypted using the cryptographic key. The request is authenticated based on encryption or decryption of the user information. The cryptographic key is deleted after the completion or termination of the user session.
| 7
|
FIELD OF THE INVENTION
The invention relates to a method for producing mop trimmings from a twisted yarn which is cut into pieces.
DESCRIPTION OF THE PRIOR ART
Yarns, in particular such of cotton, have proven their worth as trimmings for mops as long as the yarns do not untwist as a result of the use of the mop. The cleaning effect of such mop trimmings is impaired however with the increased untwisting of the yarns from the cut free end.
SUMMARY OF THE INVENTION
The invention is thus based on the object of providing a method for producing mop trimmings of the kind mentioned above in such a way that an untwisting of the yarn pieces used in the mop trimmings from their free ends can be excluded without impairing the cleaning effect.
The object is achieved in accordance with the invention in such a way that the twisted yarn is subjected to needling prior to cutting.
As a result of needling the twisted yarns, their twisting is effectively held, so that the likelihood of fringe formation by untwisting of the trimming elements as cut from the yarn is advantageously prevented, namely without any loss of cleaning effect, because the properties of the yarn pieces as demanded in connection with mop trimmings are not changed by the needling. Since the employed yarns can be needled continuously prior to cutting, the additional efforts needed can be kept relatively low since the needle-penetration density does not have to fulfill any high requirements.
Although it is known (U.S. Pat. No. 4,674,271 A, U.S. Pat. No. 5,081,753 A) to subject yarns to a treatment by needling, the yarns concern continuous yarn filaments which are to be broken by the needling in order to adapt such yarns in their properties to the usual yarns made of staple fibers. The known breakage of the continuous yarn filaments with the help of needles penetrating the yarn cannot provide any suggestion in the respect as to how mop trimmings should be treated in order to enable a permanent cleaning effect. The same applies to an other known needling method (U.S. Pat. No. 3,208,125 A) in which two filaments of continuous fibers are subjected to a needling process prior to their twisting in order to avoid any longitudinal displacement of the two filaments during the twisting. This needling prior to twisting does not prevent any untwisting of the twisted filaments.
In order to perform the needling of yarns which are used for mop trimmings according to the invention, it is possible to assume a conventional apparatus with a drivable needle board reciprocating in the direction of the needle penetration and a stitch base opposite of the needle board. It is merely necessary to ensure that the yarn cannot escape the penetrating needles. For this reason the stitch base is provided with at least one guide groove for the yarn which extends in the direction of yarn passage, with the needles of the needle board being arranged along the guide groove. With the yarn progress in the guide groove a lateral migration of the yarn to be needled is thus prevented in a simple way, so that the needling of the yarn transversally to the longitudinal direction of the yarn is ensured. The needles can be arranged along the longitudinal axis of the guide groove disposed in a line behind one another or mutually offset transversally to said axis in order to adapt the needling conditions to the respective conditions. In order to allow the needling of several yarns simultaneously, the stitching base can be provided with several parallel guide grooves for each yarn. The smooth run into and out of the guide grooves can be enforced in a simple way by means of guide eyes for the yarn.
It is understood that during the needling of the yarn it must be ensured that the material to be needled is stripped off from the needles which are moved in the drawing direction. This can be performed by stripping means which are disposed between the needle board and the stitching base on the side of the material which faces the needle board. Particularly advantageous guide conditions are obtained when the stitching base is not plane, but is provided in the known manner with an arrangement which is arched in a convex manner, because in this case a force component is obtained during the tensile load of the yarn to be needled which presses the yarn against the stitching base which renders the provision of a stripper superfluous.
BRIEF DESCRIPTION OF THE DRAWINGS
The method in accordance with the invention is now explained in closer detail by reference to the enclosed drawings, wherein:
FIG. 1 shows an apparatus in accordance with the invention for needling a twisted yarn in a simplified side view;
FIG. 2 shows a stitching base of the apparatus according to FIG. 1 in a top view on an enlarged scale;
FIG. 3 shows a partial sectional view along line III—III of FIG. 2 on an enlarged scale, and
FIG. 4 shows a partial sectional view along line IV—IV of FIG. 1 on an enlarged scale.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The apparatus according to FIG. 1 consists substantially of a stitching base 1 and a needle board 2 which is disposed opposite of the stitching base 1 , which board is inserted in the conventional manner in a needle beam 3 and can be driven in a reciprocating manner in the penetration direction of the needles 5 by means of a push rod 4 . In contrast to conventional stitching bases, the stitching base in accordance with the invention forms parallel guide grooves 6 for the yarns 7 to be needled which are held under tensile stress between a roller draw-in 8 and a roller pull-off 9 . For the purpose of guiding the yarns which are unwound from the supply coils, guide eyes 10 are diposed on the inlet side of the roller draw-in 8 . A similar set of guide eyes 10 is disposed between the stitching base 1 and the roller pull-off 9 . As is shown in FIG. 4 , the individual pass-through openings 11 of the guide eyes 10 are arranged in a division according to the guide grooves 6 in the stitching base 1 , thus producing a secure guidance of the yarns 7 in the direction of the yarn passage 12 .
According to FIG. 1 , the stitching base 1 is provided in the direction of the yarn passage 12 with a convexly arched arrangement, which leads to the force components perpendicular to the stitching base 1 in connection with the tensile stresses applied on yarns 7 by way of the roller draw-in 8 and the roller pull-off 9 . The yarns 7 are therefore pulled into the guide grooves 6 by way of said resulting forces and pressed against the stitching base so that the needles 5 of needle board 2 which penetrate the yarns 7 can be pulled out of the yarns 7 again without having to fear any entrainment of the yarns 7 . It is therefore possible to omit separate strippers between the needle board 2 and the stitching base 1 . The stitching base 1 is provided with respective pass-through openings 13 for the needles 5 . The arrangement according to the illustrated embodiment was made in such a way that the pass-through openings 13 are aligned in a straight line in the longitudinal direction of the guide grooves 6 according to the corresponding needle arrangement. Such an alignment of the needles and holes is not mandatory. In order to increase the needling effect it would be possible to provide a slight offset of the needles 5 and the pass-through holes 13 transversally to the longitudinal direction of the guide grooves 6 .
As a result of the needling of the yarns 7 transversally to the longitudinal direction of the yarns, the twisting of the yarns 7 is fixed, namely over the entire needled yarn length, so that the yarns 7 can subsequently easily be cut into pieces without any likelihood of them becoming frayed from the cut ends when said cut yarn pieces are used as trimmings for a mop. Since the yarn needling can be performed continuously, the needling of the yarns 7 can be performed within the course of a production line for mop trimmings. It is naturally also possible to wind up the needled yarns again in order to store them intermediately prior to further processing.
|
A method and an apparatus for producing mop trimmings from a twisted yarn ( 7 ) which is cut into pieces is described. In order to prevent any untwisting of the yarn pieces it is proposed that the twisted yarn ( 7 ) is subjected to a needling prior to cutting.
| 3
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is related to non-dissipative snubber circuit apparatus and more particular to non-dissipative snubber circuit apparatus for dual-switch transformer-coupled switching regulators.
2. Description of the Prior Art
Protection of transistor power switches in switching regulators by a current snubber circuit is well known in the art; see, for example, "Designing Non-Dissipative Current Snubbers For Switched Mode Converters", E. C. Whitcomb, Proceedings of POWERCON® 6, May 2-4, 1979, 1st Printing April 1979 (pre-conference edition), pp B1-1 to B1-6; "Base Drive Considerations in High Power Switching Transistors", D. Roark, TRW® Power Semiconductors Application Note, No. 120(1/75), pp 1 to 11; and "Schottky Rectifiers Shine in Low-Voltage Switchers", R. Patel, Electronic Design, Dec. 10, 1981, pp 149 to 154.
More particularly, snubber circuits, or snubbers as they are sometimes simply referred to in the art, have found general acceptance in protecting switching regulators that use only a single transistor power switch, or a pair of transistor power switches that operate in a push pull mode, i.e. alternately or out of phase. These include snubbers of both the well known dissipative and non-dissipative types.
However, heretofore, in the prior art of which I am aware, for dual-switch transformer-coupled switching regulators wherein two in phase transistor switches are in series coupled relationship with the switching transformer, only dissipative snubber types have been used. Heretofore, a non-dissipative type has not been used with these last mentioned kind of switching regulators, herein sometimes referred to as a dual switch switching regulator, because in general of the circuit complexity required for implementation and the resultant problems associated with operating the two transistors in phase.
SUMMARY OF THE INVENTION
It is an object of this invention to provide non-dissipative snubber circuit apparatus that is readily implemented with dual switch transformer coupled switching regulators.
It is another object of this invention to provide non-dissipative snubber circuit apparatus of the aforementioned kind that is simple and reliable.
According to one aspect of the present invention, in dual-switch transformer-coupled switching regulator circuit apparatus, there is provided in combination therewith snubber circuit apparatus. The regulator circuit apparatus has a pair of first and second semiconductor switch means operable in phase, and transformer means. The input winding of the transformer means is coupled in series between the first and second switch means at predetermined first and second junctions, respectively. The series coupled pair of switch means and input winding are adapted for series connection between the positive and negative terminal means of a predetermined dc supply at predetermined third and fourth junctions, respectively. The regulator circuit apparatus further has third and fourth semiconductor switch means. The third switch means is coupled between the first junction and the fourth junction. The fourth switch means is coupled between the second junction and the third junction.
In the snubber circuit apparatus there is provided first and second capacitor means, and inductor means. Each of the capacitor means has a pair of first and second electrodes. The second electrode of the capacitor means is coupled to the first junction of the regulator apparatus, and the second electrode of the second capacitor means is coupled to the second junction. First diode means couples the inductor means between the first electrodes of the first and second capacitor means. Second diode means couples the first electrode of the first capacitor means to the fourth junction. Third diode means couples the first electrode of the second capacitor means to the third junction.
The foregoing and other objects, features and advantages of the invention will be apparent from the more particular description of the preferred embodiment of the invention, as illustrated in the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic view of the preferred embodiment of the non-dissipative snubber circuit apparatus of the present invention in a known dual switch transformer coupled switching regulator partially shown in block form;
FIGS. 2A-2B are idealized waveform timing diagrams of certain voltage and current waveforms associated with the circuitry of FIG. 1; and
FIG. 3 is an idealized waveform timing diagram illustrating waveforms of the switching losses associated with the power switches of the apparatus of FIG. 1 under different conditions.
In the Figures, like elements are designated with similar reference numbers.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown a dual-switch transformer-coupled switching regulator generally indicated by the reference numeral 1. In the preferred embodiment, the regulator 1 has dual semiconductor switch means, shown by way of example as substantially two identical NPN type transistor power switches 2 and 3 arranged in common emitter configurations. Preferably, the switches 2 and 3 have fast switching times. Switches 2 and 3 are in series coupled relationship with the hereinafter described switching transformer means.
The series coupled pair of dual switches 2 and 3 are adapted to be series coupled between the positive and negative terminals 4 and 5 of an unregulated dc supply 6 at the input terminals or junctions 37 and 38. Thus, in the preferred embodiment, the collector and emitter of transistor switches 2 and 3, respectively, are connected directly to the terminals 4 and 5, respectively. Supply 6 includes a source 6a of unregulated dc voltage Vb and an associated low impedance input filter capacitor 6b. Source 6a may be a battery or other appropriate dc source which directly provides voltage Vb, hereinafter sometimes referred to as the bulk voltage. Alternatively, source 6a may be an appropriate rectified ac source which provides bulk voltage Vb, for example, from an ac line supply.
The switching transformer means 7, herein sometimes referred to simply as the switching transformer, of the preferred embodiment has a magnetic core 7a and single-ended input and output windings 8 and 9, respectively. Input winding 8, and hence transformer 7, is serially coupled between the two switches 2 and 3 at the junctions 10 and 11, respectively. Thus, in the preferred embodiment of FIG. 1, winding 8 is serially connected between the emitter of transistor switch 2 and the collector of transistor switch 3. The output winding 9 is coupled via rectifier and filter circuits 12 and 13, respectively, to the output terminals 14 and 15, which in turn are connected across the load RL.
Preferably, switches 2 and 3 are opened and closed substantially in phase by a feedback control circuit 16 which provides a common control or driver signal to the control inputs of switches 2 and 3. Thus, in the preferred embodiment, the common control signal is provided at each of the paired outputs 17-18 and 19-20 of circuit 16 which are connected to the respective base-emitter inputs of switches 2 and 3, respectively. The input of circuit 16 is connected across the output terminals 14 and 15 via conductor 21 and common ground 22 and senses the regulated output voltage at the output 14-15. Such feedback control circuits, which are well known in the art, provide a pulse train control signal with predetermined switching frequency and on/off duty cycle characteristics commensurate with the regulation desired for the dc output at terminals 14 and 15 and can adjust at least one of the characteristics' parameters to compensate for any deviations in the level of the sensed output voltage from a predetermined reference level and thereby maintain the desired dc output. Such deviations may, for example, be due to changes in the load RL, and/or input Vb, etc. Demagnetizing diode switches 23 and 24 are connected between the emitters and between the collectors, respectively, of switches 2 and 3.
The switching regulator 1 is preferably configured for a forward operational mode in which case transformer 7 has the dot polarity indicated in solid form in FIG. 1 for the windings 8 and 9. Accordingly, the rectifier 12, illustrated schematically as diode 25, is appropriately poled as shown by its solid outline form in FIG. 1. Alternatively, the regulator 1 may be configured for a flyback operational mode by locating the diode 25 in the other leg of the winding 9 as shown by the dash outline form 25'. Depending on the particular operational mode, the filter 13 is modified accordingly. Thus, in the forward operational mode, filter 13 is an LC type with the choke inductor thereof being connected between diode 25 and terminal 14 and the capacitor being connected across terminals 14 and 15 in a manner well known to those skilled in the art. On the other hand, in the flyback operational mode, only a capacitor, which is connected across the terminals 14 and 15, is required as the winding 9 acts as the choke as is well known to those skilled in the art. In the forward operational mode, it should be understood that, as is customary, there is associated with the filter 13 an appropriately poled free wheeling diode, not shown, which is connected across the input of filter 13.
The basic principles of transformer coupled switching regulators and of their forward and flyback operational modes are well known to those familiar with the art. Briefly and with respect to the dual switch transformer coupled switching regulator 1 of FIG. 1, in the forward mode when switches 2 and 3 are closed, i.e. are on, energy is transferred from winding 8 to winding 9. More particularly, diode 25 is forward biased, the aforementioned free wheeling diode is reversed biased, and the current in winding 9 passes through the aforementioned choke winding of filter 13 and divides into the two parallel branches which are formed by the aforementioned capacitor of filter 13 and the load RL. In doing so, the current in the capacitor branch is used to recharge the filter capacitor to the desired regulated dc output voltage level, and the current in the load branch is used to supply the load at the desired regulated dc output voltage level. When switches 2 and 3 are opened, diode 25 is reversed biased, the free wheeling diode is forward biased, and the energy stored in the capacitor of filter 13 in coaction with the choke inductor of filter 13 and free wheeling diode is delivered through the load RL at a rate sufficient to maintain the desired regulated dc output voltage level.
In the flyback operational mode, when switches 2 and 3 are closed, the diode 25' is reversed biased and the energy is stored in winding 8. There is no transfer of energy from winding 8 to winding 9 during this period. However, energy previously stored in the capacitor of filter 13, which has no inductor as previously explained, is delivered to the load RL at a rate sufficient to maintain the desired regulated dc output voltage level. When switches 2 and 3 are opened, diode 25' is forward biased. The energy stored in the winding 8 is transferred to winding 9, the latter also doubling as a choke as aforementioned. The current in winding 9 passes through the conducting diode 25' and divides into the two parallel branches formed by the capacitor of filter 13 and the load RL. The current in the capacitor branch recharges the capacitor to the desired regulated dc output voltage level, and the current in the load branch is used to supply the load RL at the desired regulated dc output voltage level.
Generally, the forward operational mode is used for high power applications and the flyback operational mode for low power applications. As is well known to those skilled in the art, the nominal level of the regulated output at terminals 14-15 depends inter alia on the parameters selected for the turns ratio of windings 8 and 9, the on/off duty cycle and the switching frequency.
According to the principles of the present invention, non-dissipative snubber circuit apparatus is provided in combination with a dual-switch transformer-coupled switching regulator. In FIG. 1, the preferred embodiment of the non-dissipative snubber circuit apparatus of the present invention is generally indicated by reference numeral 26. The circuit apparatus or snubber 26 has a pair of capacitors 27 and 28 and an inductor 29. The capacitors 27 and 28 each have a pair of electrodes designated 30 and 31. Electrode 31 of capacitor 27 is coupled to junction 10, and electrode 31 of capacitor 28 is coupled to junction 11. As such, electrodes 31 of capacitors 27 and 28 are coupled to the emitter and collector, respectively, of transistor switches 2 and 3, respectively. A diode switch 32 couples the inductor 29 between the electrodes 30 of capacitors 27 and 28. A second diode switch 33 couples electrode 30 of capacitor 27 to the junction 38 between the emitter of transistor switch 3 and the negative terminal 5 of supply 6. Another diode switch 34 couples electrode 30 of capacitor 28 to the junction 37 between the collector of the other transistor switch 2 and the positive terminal 4 of supply 6. As can readily be seen, snubber 26 is thus coupled across the switch terminals, to wit: collector and emitter electrodes, of each of the switches 2 and 3. Preferably, an anti-ringing circuit, i.e. capacitor 35 and resistor 36, is provided across the inductor 29.
The operation of the circuitry of FIG. 1 in the preferred forward operational mode will next be described with reference to the waveforms A-S of FIGS. 2A-2B. By way of example and/or for purposes of explanation, it will be assumed that transistor switches 2 and 3 are ideal and simultaneously turn off. The reference characters v and i, which appear parenthetically alongside the ordinate axes associated with the waveforms A-S of FIGS. 2A-2B, are used to designate voltage and current waveform types, respectively, shown thereat. The waveforms A-S in FIGS. 2A-2B are plotted on a common time axis.
As aforementioned, switches 2 and 3 are adapted to be turned on and off, i.e. closed and opened, substantially in phase by the common control signal, not shown, at the output 17-20 of circuit 16. In the preferred embodiment, the control signal is a base drive signal appearing as an adjustable recurring pulse train which produces a switching frequency 1/T with a closed switch time (Tc) to open switch time (To) ratio Tc/To, cf. FIG. 2A. Moreover, in the preferred embodiment, the output signal at terminals 14-15 is regulated by varying the ratio Tc/To and maintaining a constant switching frequency 1/T. Hence, the switching period T is also a constant k, where:
T=Tc+To=k.
Waveforms A-K, FIG. 2A, pertain to the switching regulator 1. The base currents IB2 and IB3 of transistor switches 2 and 3, respectively, are shown by the same waveform A for sake of simplicity. Waveforms B and F are the collector currents IC2 and IC3, respectively, and waveforms C and G are the collector-to-emitter voltages Vce2 and Vce3, respectively, of respective switches 2 and 3. The voltage across winding 8 and the current associated with it are shown by waveforms D and E, respectively. Waveforms H and I are the voltages at junctions 10 and 11, respectively, taken with respect to ground. The currents associated with diodes 23 and 24 are illustrated by the waveforms J and K, respectively.
It is to be understood, as is apparent to those skilled in the art, the current waveform E is the algebraic composite of certain waveforms of which one is the waveform associated with the magnetizing current IM of transformer 8. The magnetizing current IM builds up during the magnetizing period and returns to the zero level during the demagnetizing period in accordance with well known principles. Preferably, the magnetizing and demagnetizing periods are substantially equal. For sake of clarity and purposes of explanation, the waveform of the magnetizing current IM is plotted commonly with the waveform E using the same set of axes as shown in FIG. 2A. Thus, the periods t0-t6 and t6-t8 are the magnetizing and demagnetizing periods, respectively, associated with the waveform of the magnetizing current IM. During the period t0-t7, the magnetizing current IM is shown in dash-dot outline form but because during the period t7-t8 it becomes superimposed with the waveform E it hence is shown in solid outline form thereat.
Waveforms L-S, FIG. 2B, pertain to the snubber 26. Waveforms L and P are the respective charge/discharge currents associated with capacitors 27 and 28, respectively, and waveforms M and Q are the corresponding voltages taken across capacitors 27 and 28, respectively. Likewise, waveform N is the current waveform associated with inductor 29 and waveform O is the corresponding voltage taken across inductor 29. The currents associated with diode switches 33 and 34 are shown by waveforms R and S, respectively.
It is assumed for purposes of explanation that at time t0 a turn-on period Tc commences. In response to the base drive signal, the base currents of switches 2 and 3 at the beginning of the turn-on period Tc rapidly rise to their respective staturated condition levels +IB from their just previous cutoff condition levels, i.e. zero level 0, cf. waveform A.
Moreover, at time t0, as switches 2 and 3 become conductive, the dc supply 6 begins to supply current. The current leaves terminal 4 of supply 6, passes through the closed switch 2, divides at junction 10 into two current branch parallel circuit paths next to be described which are rejoined at junction 11, and returns through closed switch 3 to terminal 5 of supply 6. One of the aforementioned two paths is through the winding 8 of the switching transformer 7 of regulator 1. The other path is through the series connected resonant elements 27, 29, 28 and forward biased diode switch 32 of snubber 26. As is apparent to those skilled in the art, diode switches 33 and 34, as well as switches 23 and 24, are reversed biased at time t0.
During the rise time period t0-t1, the current in winding 8 rises at a rate which is substantially dependent on the magnetic inductance of the transformer 7 and leakage inductance of the aforementioned choke winding, not shown, of filter 13, cf. waveform E. The current in winding 8 rises from its zero level 0 to the level I1, which is dependent upon the input voltage Vb divided by the product of the reflected impedance across winding 8 and the square of the turns ratio of the windings 8 and 9. The voltage across winding 8, i.e. waveform D, likewise rises rapidly during the period t0-t1 from the zero level 0 to the level +Vt.
During the time period t1-t4, i.e. the remainder of the turn-on time period Tc, the current in winding 8 continues to rise but at a slower rate which is dependent on the magnetic inductance of transformer 7 and the self-inductance of the aforementioned choke winding of filter 13, reaching a level I2 at time t4, at which time the base drive signal from control circuit 16 begins the turn off period To for switches 2 and 3. The corresponding voltage, waveform D, remains substantially at the +Vt level during the corresponding period t1-t4.
Concurrently, at time t0 as switches 2 and 3 become conductive, the current in the other one of the aforementioned two branch circuits starts to flow in a sinusoidal manner through the series resonant circuit 27-29 of snubber 26. Thus, as shown by waveform L, N, or P, FIG. 2B, the snubber current rises from its zero level 0 at time t0 to a peak Ip at time t2 during the first quarter period t0-t2 of the resonant cycle, and then falls back to its zero level 0 at time t3 during the second quarter period t2-t3 of the resonant cycle. As the snubber current passes through the capacitors 27 and 28 during the period t0-t3, the snubber capacitors 27 and 28 are charged thereby and rise from their respective zero voltage levels 0 at time t0 to their positive +Vb/2 levels at time t2, and continue to rise thereafter to their positive levels +Vb at time t3 as shown by the waveforms M and Q, respectively.
The same snubber current passes through the snubber inductor 29 during the period t0-t3 as shown by waveform N. Moreover, as shown by waveform O, the voltage across inductor 29 during the period t0-t3 is in quadrature relationship with the snubber current and inverse phase relationship with the respective voltages M and Q of the snubber capacitors 27 and 28. Thus, the voltage across inductor 29 rises substantially instantaneously from its zero level 0 to level +Vb at time t0 and begins to fall, crossing the zero level at time t2, and continues to fall till reaching the -Vb level at time t3.
During the period t0-t2, inductor 29 has a polarity of + to - from left to right as viewed facing FIG. 1 and the snubber current, which is charging the snubber capacitors 27 and 28, is substantially provided by supply 6. During the period t2-t3, the polarity reverses across the inductor 29 and inductor 29 provides the charging current for the snubber capacitors 27 and 28 continuing to charge them to their respective levels +Vb.
The second half of the resonant cycle is effectively blocked by the rectifier action of diode 32 at time t3. More specifically, as shown by waveform O, as the inductor voltage at time t3 attempts to rise to the positive level +Vb, it reverses its polarity thereby reverse biasing the diode 32 and preventing discharge of capacitors 27 and 28 through inductor 29 for the remainder of the period Tc, as well as the subsequent period To. Any ringing in the snubber current at time t3 is mitigated by the anti-ringing circuit 35-36.
Thus, during the period t0-t3, the current waveform B or F, which represents the current passing through each of the transistor switches 2 and 3, is the algebraic composite of the current waveform E associated with the current in winding 8 and the current waveform L, N, or O associated with the current in snubber 26. During the time period t3-t4, no current passes through snubber 26 and the switches 2 and 3 pass current only through the winding 8.
At time t4, the turn-off period To of the switching cycle begins in response to the change in the base drive signal, not shown, applied to transistor switches 2 and 3 from control circuit 16. As a result, the base currents, cf. waveform A, of switches 2 and 3 at time t4 rapidly fall to respective cutoff condition levels -IB and switches 2 and 3 begin to turn-off simultaneously. However, due to the effects of storage time of the transistor switches 2 and 3, the current through winding 8, as well as its constituent magnetizing current, continues to rise during the interval t4-t5, cf. corresponding waveforms B, E and F. During this same interval, the voltage across winding 8 remains at level +Vt, cf. waveform D.
At time t5, the storage time of the transistor switches 2 and 3 ends, and the current, waveforms B and F, through switches 2 and 3 drops rapidly from the level I3 at time t5 to the zero level 0 at time t6 during the period t5-t6. Correspondingly, the base currents, waveform A, return to the zeo level 0 at time t6, and switches 2 and 3 are fully turned off.
Moreover, during the period t5-t7, the collector-to-emitter voltages Vce2 and Vce3 of switches 2 and 3 rise from their saturated condition level 0 at time t5 to their cutoff condition level +Vb at time t7 as shown by waveforms C and G. As a result, during the corresponding period t5-t7, the voltage with respect to ground at junction 10 goes from level +Vb to level 0, and the voltage with respect to ground at junction 11 goes from level 0 to level +Vb, cf. waveforms H and I.
During the period t5-t6, the transistor switches 2 and 3 are still conducting and are in the process of being fully turned off by time t6. However, because the inductance of the filter choke 7 of filter circuit 13 tends to oppose the change in current, the curent in winding 8 does not drop as rapidly and consequently drops to the level I4 at time t6, cf. waveform E.
At time t6, switches 2 and 3 are fully turned off, and the current in winding 8 rapidly drops to the level I5 at time t7 as shown by waveform E. It should be noted that, during the period t5-t7, the voltage across winding 8 drops from level +Vt, passes through the zero level 0 at time t6, and reaches its negative level -Vt at time t7 as shown by waveform D.
At time t7, diode switches 23 and 24 become forward biased. During the next period t7-t8, the magnetizing current in the winding 8 is returned directly to the supply 6 and stored in the filter capacitor 6b through the closed switches 23 and 24, cf. waveform E, J or K. The voltage across winding 8 remains at the level -Vt during the period t7-t8.
At time t8, the magnetizing current IM reaches the zero level 0 and hence there is no conduction through winding 8. As a result, the voltage, waveform D, across it goes from its level -Vt at time t8 to the zero level 0 at time t9 and remains at the zero level 0 for the rest of the period To, i.e. until the beginning of the next switching period T at time t10.
Referring now to the snubber circuit 26, as aforementioned during the period t3-t5, as well as the remainder of the period t5-t10, diode 32 is reversed biased. At time t5, the voltage at junction 10 begins to drop from its +Vb level as shown by waveform H. The resultant voltage change at junction 10 in turn is transmitted through the capacitor 27 making its electrode 30, and hence the cathode of diode 33, more negative than the anode of diode 33 whereupon diode 33 becomes forward biased. A similar action occurs with respect to the diode 34 as the result of the voltage at junction 11 beginning to rise from its -Vb level at time t5 as shown by waveform I. Accordingly, the resultant voltage change at junction 11 in turn is transmitted through the capacitor 28 making its electrode 30 and hence the anode of diode 34 more positive than the cathode of diode 34 whereupon diode 34 becomes forward biased.
As a result, during the period t5-t6, capacitors 27 and 28 rapidly begin to discharge mainly through a series circuit path beginning arbitrarily for sake of description at electrode 31 of capacitor 27, and thence in sequence through winding 8, capacitor 28, diode 34, filter capacitor 6b, diode 33 and terminating at the other electrode 30 of capacitor 27. Discharge through switches 2 and 3 is substantially negligible during the corresponding period t5-t6 due to the switches 2 and 3 presenting a higher impedance to the inductive energy stored in the transformer 7 than the impedance of capacitors 27,28. When the switches 2 and 3 completely turn off at time t6, the capacitors 27 and 28 continue to absorb the inductive energy from the transformer 7 and discharge through the last mentioned circuit path. Hence, as shown by the current waveforms L and P, the capacitors 27 and 28 are completely discharged during the period t5-t7 and their corresponding voltage waveforms drop from their respective levels +Vb to zero levels 0, at which times diode 33 and 34 become reverse biased. At time t10, the next switching cycle begins.
Should the switches 2 and 3 not turn off at the same time, the regulator 1 and snubber 26 are not adversely effected. For example, if switch 3 should begin to turn-off before switch 2, diode 34 becomes forward biased and capacitor 28 begins to discharge toward the zero voltage level 0 through diode 34, the still fully on switch 2, and winding 8. The source current continues to flow through elements 2, 8 and 3. When switch 3 is fully turned off and if switch 2 is still fully on, the inductive current of winding 8 and the discharge current of capacitor 28 flow in the closed series loop of switch 2, winding 8, and diode 34.
When capacitor 28 is fully discharged, if the switch 2 has begun to turn off or when it subsequently begins to turn off, diode 34 becomes reverse biased and diodes 33 and 24 become forward biased. As result, capacitor 27 begins to discharge through a main circuit path which includes capacitor 27, winding 8, diode 24, filter capacitor 6b and diode 33. Concurrently, the inductive current of winding 8 passes through another loop, to wit: switch 2, winding 8 and diode 24.
When switch 2 fully turns off, capacitor 27 continues to discharge through aforementioned loop which includes elements 27, 8, 24, 6b and 33. Thereafter, when capacitor 27 becomes discharged, diode 33 is reverse biased and diode 23 forward biased. The magnetizing current then passes through the closed loop which includes winding 8, diode 24, filter capacitor 6b, and diode 23. Upon termination of the magnetizing current, diodes 23 and 24 are reverse biased and no current flows in the regulator 1 or snubber 26 until the next switching cycle.
As is readily apparent to those skilled in the art, the circuit operation is slightly modified for intermediate cases which fall between the two extreme cases, i.e. between the case where switches 2 and 3 turn off simultaneously and the case where one switch remains temporarily fully on after the other is turned fully off as, for example, the case just previously described. Thus, for sake of simplicity, the circuit operation description for such an intermediate case is omitted herein. In any case, the efficacy of the apparatus of FIG. 1 is not adversely effected.
Referring to FIG. 3, for example, current and voltage waveforms 40 and 41 thereof correspond to the current and voltage waveforms of switch 2 or 3, i.e. waveforms B and C of switch 2 or waveforms F and G of switch 3, during the transient period t5-t7 that the switches 2 and 3 are turning off simultaneously. For simultaneous cutoff, the current waveforms B and F are hence superimposed as shown by the waveform 40 of FIG. 3, and likewise the corresponding voltage waveforms C and G are also superimposed as shown by the waveform 41 of FIG. 3. Therefore, for simultaneous cutoff, the switching losses, i.e. the product of the current and voltage waveforms 40 and 41 as represented by the shaded area A1 formed under the intersection of the two curves 40 and 41 between time t5 and t6, are substantially equal. However, if one of the switches should be delayed from starting turn off for some time delay, e.g. td, after the other switch turns off at time t5, nevertheless the switching losses of the delayed switch are still substantially equal to the switching losses of the aforementioned other switch. Thus, in FIG. 3, waveforms 40' and 41' represent the current and voltage waveforms associated with the delayed switch during its transient period from time t5+td to time t7+td. The switching losses associated with the delayed switch during this period are represented by the shaded area A2 under the intersection of the two curves 40' and 41' between time t5+td and time t6+td and is substantially equal to the switching losses of the other switch as represented by the area A1 under its associated curves 40 and 41 between time t5 and t6.
The apparatus of circuit 1 is readily implemented in discreet, integrated, and hybrid circuitry. Typical parameters for the apparatus of FIG. 1 are given in the following table.
TABLE
Switching Frequency 1/T--30 KH.±10%
Bulk Voltage Vb--300 v.±30%
Capacitors 27, 28, each--0.01 uf.
Inductor 29--400 uh.
Transformer leakage inductance--100 uh.
In some applications, it may be desirable that one of the switches 2, 3 be favored to deliberately turn off after the other has turned off so that one switch will have greater switching losses than the other. In such a case, this may be accomplished, for example, by merely changing the value of an appropriate one of the capacitors 27 and 28. Also, one or both of the switches 2 and 3 can have one or more additional switches connected in parallel therewith for greater current switching capacity or the like as is well known to those skilled in the art. Also, while the invention has been described with particular NPN transistor types, it may also be implemented with PNP types with an appropriate adjustment of polarity. Other modifications to the apparatus of FIG. 1 include the use of other types of driver circuits in lieu of the feedback type circuit 16.
Thus, while the invention has been described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the scope of the invention.
|
A dual-switch transformer-coupled switching regulator is provided with a non-dissipative snubber circuit arrangement wherein the resonant elements thereof include an inductor serially connected between two capacitors through a diode switch. The snubber has two other diode switches that are connected on mutually exclusive ones of the same sides of the capacitors that are connected to the inductor. Each of the last two mentioned diode switches connects the respective aforementioned side of the particular capacitor to the outer main terminal of a mutually exclusive one of the dual transistor switches of the regulator. The other side of the particular capacitor is connected to the other main terminal of the other one of the dual transistor switches. The arrangement minimizes any deleterious effects caused when the dual switches are being switched.
| 7
|
PRIORITY
[0001] This application claims priority to an application entitled “Method and apparatus for generating code in asynchronous code division multiple access mobile communication system” filed in the Korean Industrial Property Office on Feb. 19, 2003 and assigned Serial No. 2003-10353, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method and apparatus for generating a code in an asynchronous code division multiple access mobile communication system, and more particularly to a method and apparatus for generating a code in a synchronization channel for performing a cell search.
[0004] 2. Description of the Related Art
[0005] In general, mobile communication systems can be classified into synchronous systems and asynchronous systems. The synchronous systems and the asynchronous systems classified above are respectively proposed by the United States of America and Europe. Presently, with the rapid growth of the mobile communication industry, next generation mobile communication systems, which can provide data and image services as well as typical voice services, have come to light and standardization is in progress with respect to the next-generation mobile communication systems. However, in the United States of America and Europe, which employ different mobile communication systems different standardizations are being developed. From among the next-generation mobile communication systems, the next-generation mobile communication system proposed in Europe is a third generation partnership project wideband code division multiple access (hereinafter, referred to as 3GPP W-CDMA) mobile communication system. Asynchronous operation is performed between base transceiver stations in the W-CDMA mobile communication system. Further, in order to classify the base transceiver stations, different scrambling codes are assigned. For instance, when an asynchronous base transceiver station system includes 512 cells, that is, 512 base transceiver stations, each of the 512 base transceiver stations uses a separate scrambling code from among the available 512 scrambling codes.
[0006] Also, in the W-CDMA mobile communication system as described above, a mobile station must know the scrambling code assigned to a base transceiver station which provides services to the mobile station. Accordingly, the mobile station confirms a scrambling code having the strongest signal from among the signals received from peripheral base transceiver stations. This is generally called a cell search process.
[0007] As described above, for a cell search, the mobile stations having the scrambling codes in the W-CDMA mobile communication system have used general cell search algorithms, which examine the phases of all assignable scrambling codes. However, in such general cell search algorithms, considerable time is necessary for cell search, thereby causing inefficiency.
[0008] In order to solve the problem, a multilevel cell search algorithm was proposed. In order to realize the multilevel cell search algorithm, first, 512 scrambling codes are divided into 64 code groups and then 8 scrambling codes are assigned to each code groups. Further, in order to facilitate cell search, a synchronization channel (hereinafter, referred to as SCH) and a common pilot channel (hereinafter, referred to as CPICH) are used. Herein, the SCH and the CPICH are signals provided from a base transceiver station to a mobile station through a forward link. The SCH is classified into a primary synchronization channel (hereinafter, referred to as P-SCH) and a second synchronization channel (hereinafter, referred to as S-SCH).
[0009] The multilevel cell search algorithm includes the following three cell search steps:
[0010] 1) synchronizing a slot time in a slot, which is received at a maximum power, with the P-SCH transmitted from a base transceiver station;
[0011] 2) when the time slot is synchronized through step 1, detecting a frame synchronization and a base transceiver station group designation code in the base transceiver station to which a mobile station belongs, by means of the S-SCH transmitted from the base transceiver station;
[0012] 3) detecting a scrambling code in the base transceiver station by means of the CPICH, which is transmitted from the base transceiver station, on the basis of the frame synchronization and the base transceiver station group designation code searched in step 2, and finally searching a base transceiver station to which the mobile station belongs.
[0013] [0013]FIG. 1 is block diagram illustrating an example of a frame structure of a SCH and a CPICH used for cell search in a conventional W-CDMA system.
[0014] Referring to FIG. 1, one frame includes 15 slots. Herein, a P-SCH and a S-SCH are transmitted by (the unit of) a length as long as N (=256) chips at a starting portion in each slot and the P-SCH and the S-SCH are overlapped and transmitted and orthogonality is maintained between the two channels. In a CPICH, different scrambling codes are used according to base transceiver stations, and each of the scrambling codes has a period equal to a length of one frame. In the W-CDMA mobile communication system having a channel structure as described above, each of the different scrambling codes uses only one frame from a gold code row having a period of 2 18 −1 and only M (=512) number of codes from the entire usable gold codes.
[0015] All cells commonly use a first synchronization code C p utilized in the P-SCH, which is repeatedly transmitted at 256 chip interval corresponding to 1/10 of one slot in each slot. A mobile station uses the P-SCH for finding a slot timing in a received signal. That is, the mobile station receives the P-SCH and synchronizes a base transceiver station slot time by means of the first synchronization code C p (step 1).
[0016] A second synchronization code in a base transceiver station, that is, a base transceiver station group designation code C s i,1 ˜C s i,15 is mapped and transmitted to the S-SCH. The mobile station, in which the time slot is synchronized by the P-SCH, detects a base transceiver station group designation code and a frame synchronization through the S-SCH. Herein, the base transceiver station group designation code is information for determining a cell group to which a base transceiver station belongs, and it uses a comma free code. The comma free code includes 64 code words and one code word includes 15 symbols. The 15 symbols are repeatedly transmitted at each frame. Herein, values of the 15 symbols are not just transmitted. Instead, the values of the 15 symbols are mapped to one second synchronization code from among the second synchronization code C s i,1 , . . . , C s i,15 and the mapped values are transmitted. As shown in FIG. 1, an i-th second synchronization code corresponding to a symbol value ‘i’ for each slot is used as the second mapped synchronization code. The second synchronization code may be generally expressed by C s i,n . Herein, ‘i’ is an index which designates a scrambling code group and ‘n’ is an index which designates a random slot from among 15 slots included in one frame.
[0017] The 64 code words in the comma free code classifies 64 code groups. The comma free code has a characteristic in which a cyclic shift of each code word is unique. Accordingly, the second synchronization codes are correlated to each other with respect to the S-SCH during several slot intervals, and the correlated second synchronization codes are examined with respect to 64 code words and 15 cyclic shifts for each of the 64 code words, thereby obtaining information regarding a code group and a frame synchronization. Herein, the frame synchronization represents a synchronization with respect to a timing or a phase within one period in a scrambling spread code in a spread spectrum system. In the W-CDMA system, one period of a spread code and a frame length are 10 ms and which will be called_a frame synchronization (step 2).
[0018] Through steps 1 and 2 described above, the mobile station can obtain information regarding a slot synchronization, a base transceiver station group designation code and a frame synchronization by means of the P-SCH and the S-SCH. However, since the mobile station does not yet distinguish a scrambling code in a base transceiver station to which the mobile station belongs, from among eight scrambling codes in a code group in accordance with the obtained base transceiver station group designation code, a code synchronization is not completely implemented.
[0019] Accordingly, the mobile station correlates a pilot signal, which is received through a CPICH, with eight scrambling codes in the code group, so that the mobile station can distinguish a scrambling code, which will be used by the mobile station itself, from among eight scrambling codes (step 3).
[0020] As described above, for step 2, 15 second synchronization codes C s i,n must be mapped to slots in a S-SCH by a transmitter in a base transceiver station and the mapped codes must be transmitted. Accordingly, a method and apparatus for generating the second synchronization codes C s i,n must be proposed in the base transceiver station.
[0021] The second synchronization codes C s i,n can be generated by the following equation 1.
Cs i,n =(1+ j )×[ H m (0)× z (0), H m (1)× z (1), H m (2)× z (2), . . . , H m (255)× z (255)] m= 16×( k− 1) equation 1
[0022] herein, ‘k’ represents a code index corresponding to n-th slot in i-th scrambling code group (Group i) and ‘m’ is a value determining a position of a Hadamard sequence.
[0023] As expressed by equation 1, in order to generate the second synchronization codes C s i,n , the Hadamard sequence H m must be determined. Further, in order to determine the Hadamard sequence H m , ‘m’ determining the position of the Hadamard sequence must be first obtained. In equation 1, ‘k’ is defined as a parameter for determining m. An example of ‘k’, which is determined by ‘i’ and ‘n’ and determines ‘m’, is shown in table 1.
TABLE 1 scrambling code slot number group #0 #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 Group 0 1 1 2 8 9 10 15 8 10 16 2 7 15 7 16 Group 1 1 1 5 16 7 3 14 16 3 10 5 12 14 12 10 Group 2 1 2 1 15 5 5 12 16 6 11 2 16 11 15 12 Group 3 1 2 3 1 8 6 5 2 5 8 4 4 6 3 7 Group 4 1 2 16 6 6 11 15 5 12 1 15 12 16 11 2 Group 5 1 3 4 7 4 1 5 5 3 6 2 8 7 6 8 Group 6 1 4 11 3 4 10 9 2 11 2 10 12 12 9 3 Group 7 1 5 6 6 14 9 10 2 13 9 2 5 14 1 13 Group 8 1 6 10 10 4 11 7 13 16 11 13 6 4 1 16 Group 9 1 6 13 2 14 2 6 5 5 13 10 9 1 14 10 Group 10 1 7 8 5 7 2 4 3 8 3 2 6 6 5 4 Group 11 1 7 10 9 16 7 9 15 1 8 16 8 15 2 2 Group 12 1 8 12 9 9 4 13 16 5 1 13 5 12 4 8 Group 13 1 8 14 10 14 1 15 15 8 5 11 4 10 5 4 Group 14 1 9 2 15 15 16 10 7 8 1 10 8 2 16 9 Group 15 1 9 15 6 16 2 13 14 10 11 7 4 5 12 3 Group 16 1 10 9 11 15 7 6 4 16 5 2 12 13 3 14 Group 17 1 11 14 4 13 2 9 10 12 16 8 5 3 15 6 Group 18 1 12 12 13 14 7 2 8 14 2 1 13 11 8 11 Group 19 1 12 15 5 4 14 3 16 7 8 6 2 10 11 13 Group 20 1 15 4 3 7 6 10 13 12 5 14 16 8 2 11 Group 21 1 16 3 12 11 9 13 5 8 2 14 7 4 10 15 Group 22 2 2 5 10 16 11 3 10 11 8 5 13 3 13 8 Group 23 2 2 12 3 15 5 8 3 5 14 12 9 8 9 14 Group 24 2 3 6 16 12 16 3 13 13 6 7 9 2 12 7 Group 25 2 3 8 2 9 15 14 3 14 9 5 5 15 8 12 Group 26 2 4 7 9 5 4 9 11 2 14 5 14 11 16 16 Group 27 2 4 13 12 12 7 15 10 5 2 15 5 13 7 4 Group 28 2 5 9 9 3 12 8 14 15 12 14 5 3 2 15 Group 29 2 5 11 7 2 11 9 4 16 7 16 9 14 14 4 Group 30 2 5 2 13 3 3 12 9 7 16 6 9 16 13 12 Group 31 2 6 9 7 7 16 13 3 12 2 13 12 9 16 6 Group 32 2 7 12 15 2 12 4 10 13 15 13 4 5 5 10 Group 33 2 7 14 16 5 9 2 9 16 11 11 5 7 4 14 Group 34 2 8 5 12 5 2 14 14 8 15 3 9 12 15 9 Group 35 2 9 13 4 2 13 8 11 6 4 6 8 15 15 11 Group 36 2 10 3 2 13 16 8 10 8 13 11 11 16 3 5 Group 37 2 11 15 3 11 6 14 10 15 10 6 7 7 14 3 Group 38 2 16 4 5 16 14 7 11 4 11 14 9 9 7 5 Group 39 2 3 4 6 11 12 13 6 12 14 4 5 13 5 14 Group 40 2 3 6 5 16 9 15 5 9 10 6 4 15 4 10 Group 41 2 4 5 14 4 6 12 13 5 13 6 11 11 12 14 Group 42 2 4 9 16 10 4 16 15 3 5 10 5 15 6 6
[0024] Accordingly, ‘m’ reads ‘k’ corresponding to a particular slot in a desired scrambling code group through table 1 , and ‘m’ is determined by ‘k’.
[0025] Also, in equation 1, the second synchronization codes C s i,n are generated by the Hadamard sequence H m according to the value m, which determines the position of the Hadamard sequence, and a ‘z-sequence’. The Hadamard sequence H m required for generating the second synchronization codes C s i,n is generated through a matrix shown in equation 2 and the z-sequence is generated through equation 3.
H m = [ H m - 1 H m - 1 H m - 1 - H m - 1 ] , m ≥ 1 equation 2
z=<b,b,b,−b,b,b,−b,−b,b,−b,b,−b,−b,−b,−b,−b,> equation 3
[0026] As expressed by equation 3, the z-sequence includes a ‘b-sequence’. The b-sequence is defined by equation 4.
b=<x 1 ,x 2 ,x 3 ,x 4 ,x 5 ,x 6 ,x 7 ,x 8 ,x 8 ,−x 9 ,−x 10 ,−x 11 ,−x 12 ,−x 13 ,−x 14 ,−x 15 ,−x 16 > equation 4
[0027] herein, x has the same value as that of ‘a-sequence’ expressed by equation 5.
a=<x 1 ,x 2 ,x 3 , . . . ,x 16 >=<1,1,1,1,1,1,−1,−1,1,−1,1,−1,1,−1,−1,1> equation 5
[0028] The a-sequence expressed by equation 5 is also used for generating codes utilized in a P-SCH.
[0029] For instance, when it is assumed that ‘i’ is zero and ‘n’ is three, ‘k’ is determined as eight through table 1 , and therefore ‘m’ becomes 112 computed by 16×(8−1). The value ‘112’ is put into the matrix expressed by equation 2, thereby generating a Hadamard sequence corresponding to the value ‘112’. When the Hadamard sequence is generated, the generated Hadamard sequence and the z-sequence are applied to equation 1, so that a second synchronization code in a fourth slot in a first scrambling code group Group 0 is generated.
[0030] [0030]FIG. 2 is a block diagram showing a construction of an apparatus for generating the Hadamard sequence required for generating the second synchronization code as described above.
[0031] Referring to FIG. 2, a digital signal processor (not shown) determines a scrambling code group ‘Group i’, which will be used, and records code index values according to each slot, which correspond to the determined scrambling code group ‘Group i’, in a register 210 . The code index values may be expressed by 5 bits and one example of the code index values is shown in table 1. As shown in table 1, a maximum value in each scrambling code group is 16 and 5 bits is necessary for expressing the value using a binary code. The register 210 outputs code index values according to each slot, which are recorded by the digital signal processor, at a particular point in time. A multiplexer 220 receives a slot count value SCH_Slot_Cnt[3:0] determining a slot position and selects/outputs one index value ‘k’ from among 15 code index values provided from the register 210 , by means of the slot count value SCH_Slot_Cnt[3:0]. The slot count value SCH_Slot_Cnt[3:0] represents a slot position for generation of a second synchronization code. 5 bits ‘k’ output from the multiplexer 220 is input to a subtracter 240 through a buffer 230 . The subtracter 240 subtracts one from ‘k’ and provides ‘k−1’ to a multiplier 250 . The multiplier 250 multiplies ‘k−1’ by 16 and stores ‘m’, which results from the multiplication, in a buffer 260 . The buffer 260 storing ‘m’ has a length of eight. An operation by the subtracter 240 and the multiplier 250 is equal to an equation “16×(k−1)” for obtaining ‘m’.
[0032] The value ‘m’ stored in the buffer 260 is transmitted to a code generator 270 . The code generator 270 receives ‘m’ and then outputs a Hadamard sequence for generating a second synchronization code which will be transmitted through the desired slot. That is, the code generator 270 applies ‘m’ to equation 2, thereby generating the Hadamard sequence. The Hadamard sequence generated as described above is multiplied by a ‘z-sequence’, thereby generating a desired second synchronization code.
[0033] As described above, in order to generate the conventional second synchronization code, a code index corresponding to each slot is expressed by 5 bits. Accordingly, in order to store the code index, a 5 bits register including 16 areas is necessary. Further, a subtracter and a multiplier must be used for computing ‘m’, thereby increasing the difficulty in constructing an apparatus for generating the second synchronization code. Furthermore, this results in an increase in hardware size when a synchronization channel in a transmitter in a base transceiver station also increases.
SUMMARY OF THE INVENTION
[0034] Accordingly, the embodiments of the present invention solve problems occurring in the conventional systems, and an object of the present invention is to provide an apparatus for generating a second synchronization code, which can decrease the complexity and size of hardware used.
[0035] Another object of the present invention is to provide a method and apparatus for generating a second synchronization code, in which different indices in each slot, which determine code generation in a second synchronization channel, have been modified to facilitate construction of hardware.
[0036] A Further object of the present invention is to provide a method and apparatus for converting a 5 bits code index value ‘k’ into that of 4 bits, and determining a bit row, in which the 4 bit code index ‘k’ is combined with “0000”, as ‘m’.
[0037] In order to substantially accomplish the aforementioned objects, according to an embodiment of the present, there is provided a method employed in a transmitter in a mobile communication system which has multiple code groups which have inherent code indices in response to slots, selects one code group from among the multiple code groups, and generates a second synchronization code corresponding to any one slot from among multiple slots, which are included in the selected code group, the method comprises the steps of (1) in response to any one slot, outputting a value, which is obtained by subtracting 1 from a code index included in the selected code group, as a binary bit row; and (2) selecting one bit row, which employs the binary bit row as an upper bit and employs a binary code “0000” as a lower bit, as position information which designates the Hadamard code.
[0038] In order to substantially accomplish the aforementioned objects, according to an embodiment of the present, there is provided an apparatus employed in a transmitter in a mobile communication system which has multiple code groups which have inherent code indices in response to slots, selects one code group from among the multiple code groups and generates a second synchronization code corresponding to any one slot from among multiple slots which included in the selected code group, an apparatus for determining position information designating a Hadamard code necessary for generating the second synchronization code. The apparatus comprises a register for temporarily storing binary bit rows of 4 bits obtained by subtracting 1 from inherent indices corresponding to each of slots included in the selected code group; a multiplexer for selecting and outputting any one binary bit row from among the temporarily stored binary bit rows by means of a slot count value; and a buffer for outputting one bit row, which employs the binary bit row from the multiplexer as an upper bit and employs a binary code “0000” as a lower bit, as position information which designates the Hadamard code.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0040] [0040]FIG. 1 is a diagram illustrating a frame structure in a synchronization channel (SCH) and a common pilot channel (CPICH) used for searching for cells in a conventional wideband code division multiple access (W-CDMA) system;
[0041] [0041]FIG. 2 is a block diagram illustrating a construction of an apparatus for generating a Hadamard sequence required for generating a conventional second synchronization code;
[0042] [0042]FIG. 3 is a block diagram illustrating a construction of an apparatus for generating a Hadamard sequence required for generating a second synchronization code according to an embodiment of the present invention;
[0043] [0043]FIG. 4 is a block diagram illustrating a construction for generating a second synchronization code according to an embodiment of the present invention; and
[0044] [0044]FIG. 5 is a flowchart illustrating a control flow for generating a second synchronization code according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0045] Hereinafter, an embodiment according to the present invention will be described with reference to the accompanying drawings.
[0046] The embodiment of the present invention, which will be described, proposes not only a method and an apparatus for generating a Hadamard sequence required for generating a second synchronization code, but also a method and an apparatus for generating a second synchronization code, which employs the Hadamard sequence as an input. Herein, an index value ‘m’ determining a position of the Hadamard sequence is necessary for generating the Hadamard sequence, and the embodiment of the present invention proposes a method and an apparatus for generating the Hadamard sequence. That is, the embodiment proposes a method and an apparatus for converting an existing 5 bit code index value ‘k’ bits into that of 4 bits and then employing a bit row, in which the 4 bit code index value ‘k’ is combined with “0000”, as the value ‘m’. Herein, the 4 bit code index value ‘k’ is called an upper bit and “0000” combined with the 4 bit code index value ‘k’ is called a lower bit. Accordingly, ‘m’ has a structure of “k 3 , k 2 , k 1 , k 0 , 0, 0, 0, 0”.
[0047] [0047]FIG. 3 is a block diagram illustrating a construction of an apparatus for generating a Hadamard sequence required for generating a second synchronization code according to an embodiment of the present invention.
[0048] Referring to FIG. 3, a digital signal processor (not shown) determines a scrambling code group ‘Group I’, which will be used, and it records code index values according to each of 15 slots, which correspond to the determined scrambling code group ‘Group i’, in a register 310 . The code index values are values obtained by subtracting 1 from each of the code index values shown in table 1. One example of the code index values recorded in the register 310 is shown in table 2 which shows 4 bit code index values with respect to Group 0.
TABLE 2 scrambling code slot number group #0 #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 Group 0 1 1 2 8 9 10 15 8 10 16 2 7 15 7 16 (before modification) Group 0 0 0 1 7 8 9 14 7 9 15 1 6 14 6 15 (after modification)
[0049] As shown in table 2, a maximum value from among code index values with respect to Group 0 after modification is 15. Therefore 15 code index values according to each scrambling code group can be expressed by a 4 bit binary code. Accordingly, in the register 310 , an area storing code index values according to each slot has a size of 4 bits. Meanwhile, 5 bit code index value is converted into that of 4 bits, so that the DSP may record 4 bit code index values instead of recording 5 bit code index value.
[0050] The register 310 simultaneously outputs code index values according to each slot, which are recorded by the digital signal processor, at a particular point in time. A multiplexer 320 receives a slot count value SCH_Slot_Cnt[3:0] designating one slot from among 15 slots and selects/outputs one code index value ‘k’ from among 15 code index values provided from the register 310 , by means of the slot count value SCH_Slot_Cnt[3:0]. The code index value ‘k’ from the multiplexer 320 is recorded in a first buffer 330 . Since the code index value ‘k’ includes 4 bits, the first buffer 330 has a size of 4 bits. A second buffer 340 records additional bits “0000”. A bit row of 8 bits, in which ‘k’ recorded in the first buffer 330 is combined with the additional bits recorded in the second buffer 340 , is an index value ‘m’ determining a position of a Hadamard sequence expressed by “16×(k−1)”. It should be appreciated by those skilled in the art that the first buffer 330 and the second buffer 340 can be constructed using one buffer as opposed to two separate buffers as shown in FIG. 3 without departing from the scope of the present invention. When the first buffer 330 and the second buffer 340 are constructed using one buffer, an area recording ‘k’ is an upper bit recording area and an area recording the additional bits “0000” is a lower bit recording area.
[0051] An AND operation unit 350 receives 4 bit ‘k’ from the first buffer 330 and the additional bits “0000” from the second buffer 340 . The AND operation unit 350 performs a logical AND operation on ‘m’, in which ‘k’ is combined with the additional bits, and an 8 bit chip count value SCHChipCnt[7:0] by the unit of bit, thereby producing an 8 bit sequence in the unit of chip, and then outputs the produced 8 bit sequence to an XOR operation unit 360 . The chip count value SCHChipCnt [7:0] is a value of 8 bits provided by a counter counting 256 chips, which is a second synchronization code, transmitted according to 15 slots included in one frame. That is, when the slot count value SCHSlotCnt [3:0] increases by one, the chip count value SCHChipCnt [7:0] counts from one to 255. Accordingly, the AND operation unit 350 sequentially performs a logical AND operation on the binary codes from zero to 255 according to corresponding bits to each ‘m’, which is provided from the first buffer 330 and the second buffer 340 , and then outputs the operation result. As a result, the AND operation unit 350 finally outputs 256 sequences with respect to one ‘m’. Each of the sequences is a bit row of 8 bits. The XOR operation unit 360 performs a logical XOR operation on the 8 bits output from the AND operation unit 350 and outputs 1 bit. Further, the XOR operation unit 360 outputs the one bit 256 times in the same method as described above and then outputs a Hadamard sequence which results from the output.
[0052] For instance, when ‘m’ has a value of ‘10111011’ and SCHChipCnt has a value of ‘11000101’, ‘10000001’ can be obtained as the 8 bits by performing a logical AND operation according to each bit. When ‘10000001’ is input to the XOR operation unit 360 , the XOR operation unit 360 performs a logical XOR operation on all 8 bits, and therefore the result is zero. The operation repeats 256 times. Herein, the XOR operator generates one when the number of ‘1’s is odd from among input variables and generates zero when the number of ‘1’s is even from among input variables. Accordingly, in the output ‘10000001’ of the logical AND operation, since the number of ‘1’s is even, the result is zero.
[0053] [0053]FIG. 4 is block diagram illustrating a construction for generating a second synchronization code according to an embodiment of the present invention.
[0054] Referring to FIG. 4, a lower four bit SCHChipCnt [3:0] from the chip count value SCHChipCnt [7:0] is input to a first multiplexer (hereinafter, referred to as first MUX) 410 and an upper four bit SCHChipCnt [7:4] from the chip count value SCHChipCnt [7:0] is input to a second multiplexer (hereinafter, referred to as second MUX) 420 . The first MUX 410 receives a ‘b-sequence’ and selects/outputs one bit from among 15 bits included in the b-sequence by means of the lower four bit SCHChipCnt [3:0]. As defined by equation 4, the b-sequence may be expressed by an ‘a-sequence’. Also, the a-sequence is defined by <1,1,1,1,1,1,−1,−1,1,−1,1,−1,1,−1,−1,1> in equation 5. The a-sequence is expressed by <0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0> by means of a binary code, and the a-sequence expressed by the binary code is applied to equation 4, thereby obtaining a ‘b-sequence’ expressed by <0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1>. A ‘b-sequence’ arranged in reverse sequence is input to the first MUX 410 . That is, the b-sequence expressed by <1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0> is input to the first MUX 410 , and <1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0> corresponds to <−x 16 , −x 15 , −x 14 , −x 13 , −x 12 , −x 11 , −x 10 , −x 9 , x 8 , x 7 , x 6 , x 5 , x 4 , x 3 , x 2 , x 1 >. The second MUX 420 receives a ‘z-sequence’ and selects/outputs one bit from among 15 bits included in the z-sequence by means of the lower four bit SCHChipCnt [7:4]. Accordingly, the second MUX 420 selects a next bit when the first MUX 410 selects all bits. This may be a construction for meeting equation 3. The XOR operation unit 430 performs a logical XOR operation on two bits, which are respectively output from the first MUX 410 and the second MUX 420 by the chip count value SCHChipCnt [7:0], and a bit row of 8 bits, which are output through the construction in FIG. 3 by the unit of chip, by the unit of bit, and it outputs the operated result. The bit row, which is output from the XOR operation unit 430 by the unit of 8 bits by means of the chip count value SCHChipCnt [7:0], corresponds to one chip in a second synchronization code of 256 chips corresponding to a desired slot. Also, a sequence from the XOR operation unit 430 may be output by a flip-flop 440 by the unit of chip or 256 chips.
[0055] [0055]FIG. 5 is a flowchart illustrating a control flow for generating a second synchronization code according to an embodiment of the present invention. In FIG. 5, steps 510 to 516 correspond to a construction for generating ‘m’ in FIG. 3 and step 518 corresponds to a construction for generating a Hadamard sequence by means of ‘m’ in FIG. 3. A step 520 in FIG. 5 corresponds to a construction in FIG. 4 for generating a desired second synchronization code by means of a Hadamard sequence.
[0056] Referring to FIG. 5, in step 510 , a predetermined second synchronization code is designated. As a result of the designation, a predetermined scrambling code group and one slot from among 15 slots corresponding to the scrambling code group are selected. When the second synchronization code is designated, a code index ‘k’ corresponding to one slot is selected from among the slots in the scrambling code group in response to the second synchronization code in step 512 . In step 514 , a new ‘k’ is obtained by subtracting 1 from the selected code index ‘k’ and. In step 516 , ‘m’ is selected which employs ‘k’ as an upper bit and employs ‘0000’ as a lower bit. Then, step 518 is performed. That is, a Hadamard sequence corresponding to the selected ‘m’ is generated. In step 520 , a second synchronization code, which will be transmitted, is generated through a corresponding slot in the scrambling code group by means of the generated Hadamard sequence.
[0057] Hereinafter, an operation according to an embodiment of the present invention will be in detail described with reference to drawings described above.
[0058] First, an operation for generating a Hadamard sequence will be described with reference to FIG. 3. an operation DSP selects a predetermined scrambling code group and outputs 4 bit code index values corresponding to each of 15 slots in the selected scrambling code group. The 4 bit code index values are values obtained by subtracting 1 from each of code index values shown in table 1. Each of the 4 bit code index values is recorded in a corresponding recording area from among 15 recording areas in a register 310 . The 15 code index values recorded in the register 310 are output at the same point in time and one code index from 15 code indices is selected and output by the multiplexer 320 employing the slot count value SCH_Slot_Cnt [3:0] as an input value. Herein, the slot count value SCH_Slot_Cnt [3:0] is a value counted by a counter (not shown) operating at each slot in the selected scrambling code group. That is, the multiplexer 320 selects a code index corresponding to a slot, which wants to generate a second synchronization code, from among 15 slots in a scrambling code group which will be used. The code index output from the multiplexer 320 is 4 bits and recorded as ‘k index[3:0] in the first buffer 330 . This is used as an upper bit of ‘m’ necessary for generating Hadamard sequence and 4 bits recorded in the second buffer 340 is used as lower bits of ‘m’. The 4 bits recorded in the second buffer 340 is “0000”. 8 bit ‘m’, in which the upper bit is combined with the lower bit, is provided to the AND operation unit 350 . Then, the AND operation unit 350 performs a logical AND operation on ‘m’ and a chip count value SCHChipCnt [7:0] by the unit of bit. One example of sequences output from the AND operation unit 350 is shown in table 3.
TABLE 3 m SCHChipCnt[7:0] AND K 3 , k 2 , k 1 , k 0 , 0, 0, 0, 0 00000000 0, 0, 0, 0, 0, 0, 0, 0 00000001 0, 0, 0, 0, 0, 0, 0, 0 00000010 0, 0, 0, 0, 0, 0, 0, 0 00000011 0, 0, 0, 0, 0, 0, 0, 0 00000100 0, 0, 0, 0, 0, 0, 0, 0 . . . . . . 01101111 0, k 2 , k 1 , 0, 0, 0, 0, 0 01110000 0, k 2 , k 1 , k 0 , 0, 0, 0, 0 . . . . . . 11111100 K 3 , k 2 , k 1 , k 0 , 0, 0, 0, 0 11111101 K 3 , k 2 , k 1 , k 0 , 0, 0, 0, 0 11111110 K 3 , k 2 , k 1 , k 0 , 0, 0, 0, 0 11111111 K 3 , k 2 , k 1 , k 0 , 0, 0, 0, 0
[0059] The sequences, which are output from the AND operation unit 350 , are input to the XOR operation unit 360 . Then, the XOR operation unit 360 performs a logical XOR operation on all of the 8 bit sequences, thereby outputting a final Hadamard sequence. Accordingly, 256 sequences of 8 bits are generated as the final Hadamard sequence in response to one ‘m’ and 256 sequences represent 256 chips. The Hadamard sequence of 256 chips may be expresses by “H m (0), H m (1), H m (2), . . . ,H m (255)”.
[0060] Hereinafter, ‘m’ will be obtained by means of the first scrambling code group ‘Group # 0 ’ and the fourth slot # 3 , as an example.
[0061] The operation DSP reads 15 code index values “1, 1, 2, 8, 9, 10, 15, 8, 10, 16, 2, 7, 15, 7, 16”, which are recorded in each slot in the ‘Group # 0 ’, from table 1. Further, the operation DSP records code index values “0, 0, 1, 7, 8, 9, 14, 7, 9, 15, 1, 6, 14, 6, 15”, which are obtained by substracting 1 from each of the read code index values, according to a corresponding recording area in the register 310 . The code index values before modification and the code index values after modification are shown in table 2. The values recorded in the register 310 are binary code values which convert the code index values, which are obtained by subtracting 1, into binary codes. For instance, 7 is converted into “0111” and the converted value is recorded. Further, 15 is converted into “1111” and the converted value is recorded. The 15 code index values recorded as the binary code in the register 310 are input to the multiplexer 320 . Further, a slot count value “0011” selecting the fourth slot # 3 is input to the multiplexer 320 . Accordingly, the multiplexer 320 outputs a code index value “0111” corresponding to the fourth slot from among the 15 code index values. The output code index value “0111” is recorded in the first buffer 330 . The “0111” recorded in the first buffer 330 is combined with “0000” recorded in the second buffer 340 . From the result of the combination, “01110000” is obtained and then input to the AND operation unit 350 . The “01110000” input to the AND operation unit 350 becomes the index value ‘m’ which determines a position of a Hadamard sequence. The ‘m’ obtained by the example described above has the same value as that of ‘m’ computed by the conventional “16×(k−1)”. That is, in the aforementioned example, since it is assumed that ‘k’ is 8, ‘m’ has a value of 112 according to the conventional method. The value of 112 is expressed by “01110000” by means of an 8 bit binary code, and “01110000” is the same as ‘m’ according to a method proposed in the present invention.
[0062] Next, an operation for generating a second synchronization code will be described with reference to FIG. 4. 16 bit b-sequence is input to the first MUX 410 and 16 bit z-sequence is input to the second MUX 420 . The first MUX 410 outputs one bit ‘b out ’, which is selected by lower 4 bits SCHChipCnt [3:0] from among an 8 bit chip count value SCHChipCnt [7:0], from 16 bit b-sequence. The second MUX 420 outputs one bit ‘z out ’, which is selected by upper 4 bits SCHChipCnt [7:4] from among the 8 bit chip count value SCHChipCnt [7:0], from 16 bit z-sequence.
[0063] An input/output relation between the first MUX 410 and the second MUX 420 is shown in table 4.
TABLE 4 SCHChipCnt [7:0] b-sequence z-sequence b out z out 0000 0000 b 16, b 15, b 14, z 16, z 15, z 14, b 1 z 1 0000 0001 b 13, b 12, b 11, z 13, z 12, z 11, b 2 z 1 0000 0010 b 10, b 9, b 8, b 7, z 10, z 9, z 8, z 7, b 3 z 1 . b 6, b 5, b 4, b 3, z 6, z 5, z 4, z 3, . . . b 2, b 1 z 2, z 1 . . . . . 0000 1111 b 16 z 1 0001 0000 b 1 z 2 0001 0001 b 2 z 2 . . . . . . . . . 0001 1111 b 16 z 2 0010 0000 b 1 z 3 0010 0001 b 2 z 3 . . . . . . . . . 1111 1111 b 16 z 16
[0064] As shown in table 4, each bit in the b-sequence is sequentially selected by the lower 4 bits in the chip count value SCHChipCnt [7:0] and each bit in the z-sequence is sequentially selected by the upper 4 bits in the chip count value SCHChipCnt [7:0]. Accordingly, the number of combinations of bits output from the first MUX 410 and the second MUX 420 is 256. In table 4, the b-sequence b n is expressed by <b 16 , b 15 , b 14 , b 13 , b 12 , b 11 , b 10 , b 9 , b 8 , b 7 , b 6 , b 5 , b 4 , b 3 , b 2 , b 1 >, and ‘n’ corresponds to the lower 4 bits. Further, the z-sequence z m is expressed by <z 16 , z 15 , z 14 , z 13 , z 12 , z 11 , z 10 , z 9 , z 8 , z 7 , z 6 , z 5 , z 4 , z 3 , z 2 , z 1 >, and ‘m’ corresponds to the upper 4 bits.
[0065] The output b out from the first MUX 410 and output z out from the second MUX 420 are input to the XOR operation unit 430 . Further, a Hadamard sequence H m (SCHChipCnt [7:0]) is input to the XOR operation unit 430 as the other input. The Hadamard sequence H m (SCHChipCnt [7:0]) represents a Hadamard sequence corresponding to a current chip count value SCHChipCnt [7:0] and the Hadamard sequence H m (SCHChipCnt [7:0]) is generated by the Hadamard generator shown in FIG. 3. The XOR operation unit 430 performs a logical XOR operation on ‘b out ’, ‘z out ’ and the Hadamard sequence H m (SCHChipCnt [7:0]). Based on the result of the logical XOR operation, the XOR operation unit 430 outputs a second synchronization code by the unit of 8 bit chips.
[0066] An input/output relation in the XOR operation unit 430 is shown in table 5.
TABLE 5 b out z out Hadamard Code XOR_out b 1 z 1 H m (0) b 1 ⊕ z 1 ⊕ H m (0) b 2 z 1 H m (0) b 2 ⊕ z 1 ⊕ H m (0) b 3 z 1 H m (0) b 3 ⊕ z 1 ⊕ H m (0) . . . . . . . . . . . . b 16 z 1 H m (0) b 16 ⊕ z 1 ⊕ H m (0) b 1 z 2 H m (1) b 1 ⊕ z 2 ⊕ H m (1) b 2 z 2 H m (1) b 2 ⊕ z 2 ⊕ H m (1) . . . . . . . . . . . . b 16 z 2 H m (1) b 16 ⊕ z 2 ⊕ H m (0) b 1 z 3 H m (2) b 1 ⊕ z 3 ⊕ H m (2) b 2 z 3 H m (2) b 2 ⊕ z 3 ⊕ H m (2) . . . . . . . . . . . . b 16 z 16 H m (255) b 16 ⊕ z 16 ⊕ H m (255)
[0067] The XOR_out shown in table 5 is a second synchronization code in the unit of chip and the XOR_out may be expressed by equation 1 through generalization.
[0068] Also, the aforementioned operation repeats 256 times in response to a generated one ‘m’ as implied through the description above. As a result of the operation, a second synchronization code of 256 chips, which will be transmitted through one slot, is generated.
[0069] In the embodiment of the present invention as described above, 4 bit code index values are used in response to a slot in a particular scrambling code group, thereby reducing a size of a register storing a code index according to each slot. Further, when a data bus structure constructed by 32 bit words is used, 4 bit code index values are used, so that total two words (4 bits×eight slots, 4 bits×seven slots) are used, thereby decreasing access times in operation digital signal processing. Furthermore, separate operators are not used for determining ‘m’, thereby simplifying a construction of the second synchronization code.
[0070] While the invention has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
|
A method and apparatus for generating a code in an asynchronous code division multiple access mobile communication system is provided. Specifically, the method and apparatus are for use in a transmitter in a mobile communication system which has multiple code groups having inherent code indices in response to each of slots, which selects one code group from among the multiple code groups, and which generates a second synchronization code corresponding to any one slot from among multiple slots, which are included in the selected code group. The method and apparatus determine position information designating a Hadamard code necessary for generating the second synchronization code by performing the steps of (1) in response to any one slot, outputting a value, which is obtained by subtracting 1 from a code index included in the selected code group, as a binary bit row; and (2) selecting one bit row, which employs the binary bit row as an upper bit and employs a binary code “0000” as a lower bit, as position information which designates the Hadamard code.
| 7
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the invention
[0002] The present invention relates to a method for fabricating a semiconductor device, and more particularly to a method for fabricating a semiconductor device in which high dielectric material HfO 2 /HfSi x O y is employed, wherein “X” is 0.4˜0.6 and “Y” is 1.5˜2.5.
[0003] 2. Description of the Prior Art
[0004] According to Moore's law, semiconductor devices have been realized with the linewidth decrease of a MOSFET device and the thickness decrease of a SiO 2 film. That is, improving the integration rate and the capability of semiconductor devices through such decreases in size have been achieved, first of all, by decreasing the linewidth of a MOSFET device and the physical thickness of a SiO 2 film which is used as a gate oxide film.
[0005] However, when a SiO 2 film having a thickness of 20 Å or less is used in the prior art, leakage current increases due to quantum mechanic tunneling of electrons, so that application of a device is impossible. Particularly, in a case of storage devices such as a memory and so forth, leakage current increase in a gate oxide film has a decisively bad effect upon the reliability guarantee of the devices, so development of new materials has been required.
SUMMARY OF THE INVENTION
[0006] Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide a method for fabricating a semiconductor device using high dielectric material HfO 2 thicker than SiO 2 as a gate oxide film, and thereby proving a semiconductor device capable of preventing leakage current caused by direct tunneling of SiO 2 .
[0007] In order to accomplish this object, there is provided a method for fabricating a semiconductor device using high dielectric material, the method comprising the steps of: forming an Hf thin film on a silicon substrate; oxidizing the Hf thin film by performing an oxidizing process; and performing an annealing process after the oxidizing process, thereby forming a gate oxide film comprising an HfSi x O y thin film and an HfO 2 thin film on the silicon substrate, in which “X” is 0.4˜0.6 and “Y” is 1.5˜2.5.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0009] [0009]FIGS. 1A and 1B are cross-sectional views showing a process of a fabrication method of a semiconductor device using high dielectric material according to the present invention;
[0010] [0010]FIGS. 2A and 2B are TEM photographs of a semiconductor device using high dielectric material according to the present invention, in which FIG. 2A is a high-resolution TEM photograph before annealing of a gate oxide film, which an Hf metal thin film is deposited by a rf-magnetron sputtering method and then is oxidized, so as to have an HfO 2 /HfSi x O y multi-layer structure formed, and FIG. 2B is a high-resolution TEM photograph after annealing of the gate oxide film;
[0011] [0011]FIGS. 3A and 3B are graphs showing atomic concentration according to sputtering time, so as to explain the thickness decrease of an HfSi x O y portion (flat area) compounded of Hf, O, and Si in a case of a gate oxide film having an HfO 2 /HfSi x O y multi-layer structure in a semiconductor device using high dielectric material according to the present invention, in which FIG. 3A is a graph before annealing and FIG. 3B is a graph after annealing;
[0012] [0012]FIG. 4 is a graph showing refractive index according to photo energy in a method for fabricating a semiconductor device using a dielectric material according to the present invention;
[0013] [0013]FIG. 5 is a graph showing capacitance according to gate voltage V G , containing a smaller graph showing voltage to current density, before and after annealing of an Al-HfO 2 /HfSi x O y -Si capacitor, in a method for fabricating a semiconductor device using a dielectric material according to the present invention; and
[0014] [0014]FIG. 6 is a graph showing capacitance according to gate voltage V G , containing a smaller graph showing voltage to current density, after annealing of a Pd-HfO 2 /HfSi x O y -Si capacitor, in a method for fabricating a semiconductor device using a dielectric material according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. In the following description and drawings, the same reference numerals are used to designate the same or similar components, and so repetition of the description on the same or similar components will be omitted.
[0016] [0016]FIGS. 1A and 1B are cross-sectional views showing a process of a fabrication method of a semiconductor device using high dielectric material according to the present invention.
[0017] [0017]FIGS. 2A and 2B are TEM images of a semiconductor device using high dielectric material according to the present invention. FIG. 2A is a high-resolution TEM images before heat treatment of a gate oxide film, which an Hf metal thin film is deposited by nonreactive rf-magnetron sputtering method and then is oxidized, so as to have an HfO 2 /HfSi x O y multi-layer structure formed. FIG. 2B is a high-resolution TEM images after annealing of the gate oxide film.
[0018] [0018]FIGS. 3A and 3B are graphs showing atomic concentration according to sputtering time, so as to explain the thickness decrease of an HfSi x O y portion (flat area) compounded of Hf, O, and Si in a case of a gate oxide film having an HfO 2 /HfSi x O y multi-layer structure in a semiconductor device using high dielectric material according to the present invention. FIG. 3A is a graph before annealing and FIG. 3B is a graph after annealing.
[0019] [0019]FIG. 4 is a graph showing refractive index according to photo energy in a method for fabricating a semiconductor device using a dielectric material according to the present invention.
[0020] [0020]FIG. 5 is a graph showing capacitance according to gate voltage V G , containing a smaller graph showing voltage to current density, before and after annealing of an Al-HfO 2 /HfSi x O y -Si capacitor, in a method for fabricating a semiconductor device using a dielectric material according to the present invention.
[0021] [0021]FIG. 6 is a graph showing capacitance according to gate voltage V G , containing a smaller graph showing voltage to current density, after annealing of a Pd-HfO 2 /HfSi x O y -Si capacitor, in a method for fabricating a semiconductor device using a dielectric material according to the present invention.
[0022] According to a method for fabricating a semiconductor device using a dielectric material according to the present invention, as shown in FIG. 1A, an Hf thin film 23 is deposited on a silicon substrate 21 using a nonreactive rf-magnetron sputtering method which has excellent electrical properties.
[0023] Then, as shown in FIG. 1B, after the Hf thin film 23 is deposited, an oxidation process is performed at a temperature of about 500° C. for 120 min in a furnace, and thereby an HfO 2 thin film 23 a is formed. At this time, an Hf-silicate film, which is a thermally stable amorphous layer, that is, an HfSi x O y thin film 27 is formed between HfO 2 and Si during the fabricating process of the HfO 2 thin film. Such HfSi x O y film 27 , which is an amorphous layer, has a smaller dielectric constant (˜ 13 ) than an HfO 2 thin film, however, it performs the important function of preventing leakage current.
[0024] Subsequently, an HfO 2 thin film 23 a and an HfSi x O y thin film 27 , wherein “X” is 0.4˜0.6 and “Y” is 1.5˜2.5, are annealed at a temperature of about 500° C. in N 2 ambient, thereby forming a gate oxide film 29 of a semiconductor device.
[0025] Next, although they are not shown in drawings, an electrode (not shown) using a metal such as Al, Pd, etc. is formed on the gate oxide film 29 .
[0026] A phenomenon, in which the thickness of the HfSi x O y thin film 27 decreases while the thickness of the HfO 2 thin film 23 a increases through such an annealing process, can be understood well with reference to FIGS. 2 and 3 showing physical properties and FIGS. 5 and 6 showing electrical properties. Particularly, in a case of Al-HfO 2 /HfSi x O y -Si capacitor shown in FIG. 5, after annealing, its capacitance increases owing to the thickness reduction of HfSi x O y having a low dielectric constant of 13 or less, and also leakage current characteristics are obtained due to the existence of the amorphous HfSi x O y .
[0027] In other words, it is understood that a structural potential is formed by selective reaction of HfO 2 and HfSi x O y during an oxidation and annealing. That is, owing to the diffusion of Si and O after annealing, the thickness of HfO 2 increases, while the thickness of the HfSi x O y is reduced.
[0028] Also, as shown in FIG. 6, a Pd-HfO 2 /HfSi x O y -Si capacitor, which employs a palladium electrode having a low activity, has an equivalent oxide thickness (EOT) of 14 Å and generates a leakage current of about 5×10 −3 A/cm 2 at 2 V after compensating the flatband voltage of 1 V(i.e., measured at 3 V), which confirms that the Pb-HfO 2 /HfSi x O y -Si capacitor is superior to an Al-HfO 2 /HfSi x O y -Si capacitor.
[0029] In order to show that not an SiO 2 layer but an HfSi x O y layer is generated as an amorphous layer between an HfO 2 film and an Si substrate, FIG. 4 shows comparison of a refractive index of the HfSi x O y layer with an existing refractive index of the SiO 2 layer which has been already reported. The refractive index of a thin film according to the present invention is measured in the HfO 2 layer and the interface layer thereof by spectroscopic ellipsometry (SE) analysis for photon energies ranging from 0.7 to 4.5 eV, in which a used sample has been oxidized in O 2 ambient and then annealed in N 2 ambient.
[0030] In comparison with the refractive indexes of SiO 2 and HfO 2 which have been generally known, the refractive index of the HfO 2 layer of oxidized thin film is similar to a reported refractive index of HfO 2 , while the refractive index of the interface layer thereof shows a difference from a reported refractive index of SiO 2 . This implies that an amorphous interface layer shown in the TEM images comprises not only SiO 2 but is a compound of Hf-silicate or SiO 2 , HfO 2 , Hf, etc., as understood by an AES analysis,.
[0031] As described above, with a semiconductor device fabricated using high dielectric material according to the present invention, the reliability of the device can be improved owing to the use of high dielectric material HfO 2 , while it is difficult to use a SiO 2 film of 0.1 μm or less, which is the conventional gate oxide film, as a semiconductor device. That is, since thick HfO 2 is used so as to enable the effect of thin SiO 2 to be obtained, leakage current can be reduced. Furthermore, the number of net dies per wafer can increase, so that the integration rate of a device can be improved.
[0032] Also, in a case of constructing a transistor with a semiconductor device fabricated according to the present invention, driving current can increase due to more electric charge in an inversion region, and a short channel effect and sub-threshold current can be reduced because electric charge is easily controlled.
[0033] In addition, a transistor can be stably operated with a low threshold voltage.
[0034] Although a preferred embodiment of the present invention has been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.
|
Disclosed is a method for fabricating a semiconductor device using high dielectric material. The method comprises the steps of: forming an Hf thin film on a silicon substrate; oxidizing the Hf thin film by performing an oxidizing process; and performing an annealing process after the oxidizing process, thereby forming a gate oxide film comprising an HfSi x O y thin film and an HfO 2 thin film on the silicon substrate, in which “X” is 0.4˜0.6 and “Y” is 1.5˜2.5. Therefore, since a high dielectric material HfO 2 , which is thicker than SiO 2 , is used, leakage current caused by direct tunneling of SiO 2 can be prevented.
| 2
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Ser. No. 60/973,761 filed 19 Sep. 2007. The disclosure of this application is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to deuterium-enriched larotaxel, pharmaceutical compositions containing the same, and methods of using the same.
BACKGROUND OF THE INVENTION
[0003] Larotaxel, shown below, is a well known semi-synthetic derivative of the taxane 10-deacetylbaccatin III.
[0000]
[0000] Since larotaxel is a known and useful pharmaceutical, it is desirable to discover novel derivatives thereof. Larotaxel is described in U.S. Pat. Nos. 5,906,990, 5,254,580, 5,403,858, 5,698,582, 5,714,512, 5,750,561, 6,156,789, 7,074,821, 6,384,071, 5,814,658, and 6,150,541; the contents of which are incorporated herein by reference.
SUMMARY OF THE INVENTION
[0004] Accordingly, one object of the present invention is to provide deuterium-enriched larotaxel or a pharmaceutically acceptable salt thereof.
[0005] It is another object of the present invention to provide pharmaceutical compositions comprising a pharmaceutically acceptable carrier and a therapeutically effective amount of at least one of the deuterium-enriched compounds of the present invention or a pharmaceutically acceptable salt thereof.
[0006] It is another object of the present invention to provide a method for treating breast cancer, comprising administering to a host in need of such treatment a therapeutically effective amount of at least one of the deuterium-enriched compounds of the present invention or a pharmaceutically acceptable salt thereof.
[0007] It is another object of the present invention to provide a novel deuterium-enriched larotaxel or a pharmaceutically acceptable salt thereof for use in therapy.
[0008] It is another object of the present invention to provide the use of a novel deuterium-enriched larotaxel or a pharmaceutically acceptable salt thereof for the manufacture of a medicament (e.g., for the treatment of breast cancer).
[0009] These and other objects, which will become apparent during the following detailed description, have been achieved by the inventor's discovery of the presently claimed deuterium-enriched larotaxel.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0010] Deuterium (D or 2 H) is a stable, non-radioactive isotope of hydrogen and has an atomic weight of 2.0144. Hydrogen naturally occurs as a mixture of the isotopes 1 H (hydrogen or protium), D ( 2 H or deuterium), and T ( 3 H or tritium). The natural abundance of deuterium is 0.015%. One of ordinary skill in the art recognizes that in all chemical compounds with a H atom, the H atom actually represents a mixture of H and D, with about 0.015% being D. Thus, compounds with a level of deuterium that has been enriched to be greater than its natural abundance of 0.015%, should be considered unnatural and, as a result, novel over their non-enriched counterparts.
[0011] All percentages given for the amount of deuterium present are mole percentages.
[0012] It can be quite difficult in the laboratory to achieve 100% deuteration at any one site of a lab scale amount of compound (e.g., milligram or greater). When 100% deuteration is recited or a deuterium atom is specifically shown in a structure, it is assumed that a small percentage of hydrogen may still be present. Deuterium-enriched can be achieved by either exchanging protons with deuterium or by synthesizing the molecule with enriched starting materials.
[0013] The present invention provides deuterium-enriched larotaxel or a pharmaceutically acceptable salt thereof. There are nineteen hydrogen atoms in the larotaxel portion of larotaxel as show by variables R 1 -R 19 in formula I below.
[0000]
[0014] The hydrogens present on larotaxel have different capacities for exchange with deuterium. Hydrogen atoms R 1 -R 3 are easily exchangeable under physiological conditions and, if replaced by deuterium atoms, it is expected that they will readily exchange for protons after administration to a patient. The remaining hydrogen atoms are not easily exchangeable for deuterium atoms. Further, larotaxel is a semisynthetic derivative of taxol. Deuterium atoms at the positions indicated by the R groups may be incorporated in various combinations by the use of deuterated starting materials or intermediates during the semisynthesis of larotaxel from taxol.
[0015] The present invention is based on increasing the amount of deuterium present in larotaxel above its natural abundance. This increasing is called enrichment or deuterium-enrichment. If not specifically noted, the percentage of enrichment refers to the percentage of deuterium present in the compound, mixture of compounds, or composition. Examples of the amount of enrichment include from about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 16, 21, 25, 29, 33, 37, 42, 46, 50, 54, 58, 63, 67, 71, 75, 79, 84, 88, 92, 96, to about 100 mol %. Since there are 19 hydrogens in larotaxel, replacement of a single hydrogen atom with deuterium would result in a molecule with about 5% deuterium enrichment. In order to achieve enrichment less than about 5%, but above the natural abundance, only partial deuteration of one site is required. Thus, less than about 5% enrichment would still refer to deuterium-enriched larotaxel.
[0016] With the natural abundance of deuterium being 0.015%, one would expect that for approximately every 6,667 molecules of larotaxel (1/0.00015=6,667), there is one naturally occurring molecule with one deuterium present. Since larotaxel has 19 positions, one would roughly expect that for approximately every 126,673 molecules of larotaxel (19×6,667), all 19 different, naturally occurring, mono-deuterated larotaxels would be present. This approximation is a rough estimate as it doesn't take into account the different exchange rates of the hydrogen atoms on larotaxel. For naturally occurring molecules with more than one deuterium, the numbers become vastly larger. In view of this natural abundance, the present invention, in an embodiment, relates to an amount of an deuterium enriched compound, whereby the enrichment recited will be more than naturally occurring deuterated molecules.
[0017] In view of the natural abundance of deuterium-enriched larotaxel, the present invention also relates to isolated or purified deuterium-enriched larotaxel. The isolated or purified deuterium-enriched larotaxel is a group of molecules whose deuterium levels are above the naturally occurring levels (e.g., 5%). The isolated or purified deuterium-enriched larotaxel can be obtained by techniques known to those of skill in the art (e.g., see the syntheses described below).
[0018] The present invention also relates to compositions comprising deuterium-enriched larotaxel. The compositions require the presence of deuterium-enriched larotaxel which is greater than its natural abundance. For example, the compositions of the present invention can comprise (a) a μg of a deuterium-enriched larotaxel; (b) a mg of a deuterium-enriched larotaxel; and, (c) a gram of a deuterium-enriched larotaxel.
[0019] In an embodiment, the present invention provides an amount of a novel deuterium-enriched larotaxel.
[0020] Examples of amounts include, but are not limited to (a) at least 0.01, 0.02, 0.03, 0.04, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, to 1 mole, (b) at least 0.1 moles, and (c) at least 1 mole of the compound. The present amounts also cover lab-scale (e.g., gram scale), kilo-lab scale (e.g., kilogram scale), and industrial or commercial scale (e.g., multi-kilogram or above scale) quantities as these will be more useful in the actual manufacture of a pharmaceutical. Industrial/commercial scale refers to the amount of product that would be produced in a batch that was designed for clinical testing, formulation, sale/distribution to the public, etc.
[0021] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0022] wherein R 1 -R 19 are independently selected from H and D; and the abundance of deuterium in R 1 -R 19 is at least 5%. The abundance can also be (a) at least 11%, (b) at least 16%, (c) at least 21%, (d) at least 26%, (e) at least 32%, (f) at least 37%, (g) at least 42%, (h) at least 47%, (i) at least 53%, (j) at least 58%, (k) at least 63%, (l) at least 68%, (m) at least 74%, (n) at least 79%, (o) at least 84%, (p) at least 89%, (q) at least 95%, and (r) 100%.
[0023] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 3 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0024] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 4 -R 12 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0025] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 13 -R 17 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0026] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 18 -R 19 is at least 50%. The abundance can also be (a) 100%.
[0027] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0028] wherein R 1 -R 19 are independently selected from H and D; and the abundance of deuterium in R 1 -R 19 is at least 5%. The abundance can also be (a) at least 11%, (b) at least 16%, (c) at least 21%, (d) at least 26%, (e) at least 32%, (f) at least 37%, (g) at least 42%, (h) at least 47%, (i) at least 53%, (j) at least 58%, (k) at least 63%, (l) at least 68%, (m) at least 74%, (n) at least 79%, (o) at least 84%, (p) at least 89%, (q) at least 95%, and (r) 100%.
[0029] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 3 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0030] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 4 -R 12 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0031] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 13 -R 17 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0032] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 18 -R 19 is at least 50%. The abundance can also be (a) 100%.
[0033] In another embodiment, the present invention provides novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0000] wherein R 1 -R 19 are independently selected from H and D; and the abundance of deuterium in R 1 -R 19 is at least 5%. The abundance can also be (a) at least 11%, (b) at least 16%, (c) at least 21%, (d) at least 26%, (e) at least 32%, (f) at least 37%, (g) at least 42%, (h) at least 47%, (i) at least 53%, (j) at least 58%, (k) at least 63%, (l) at least 68%, (m) at least 74%, (n) at least 79%, (o) at least 84%, (p) at least 89%, (q) at least 95%, and (r) 100%.
[0034] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 3 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0035] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 4 -R 12 is at least 11%. The abundance can also be (a) at least 22%, (b) at least 33%, (c) at least 44%, (d) at least 56%, (e) at least 67%, (f) at least 78%, (g) at least 89%, and (h) 100%.
[0036] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 13 -R 17 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0037] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 18 -R 19 is at least 50%. The abundance can also be (a) 100%.
[0038] In another embodiment, the present invention provides novel pharmaceutical compositions, comprising: a pharmaceutically acceptable carrier and a therapeutically effective amount of a deuterium-enriched compound of the present invention.
[0039] In another embodiment, the present invention provides a novel method for treating breast cancer comprising: administering to a patient in need thereof a therapeutically effective amount of a deuterium-enriched compound of the present invention.
[0040] In another embodiment, the present invention provides an amount of a deuterium-enriched compound of the present invention as described above for use in therapy.
[0041] In another embodiment, the present invention provides the use of an amount of a deuterium-enriched compound of the present invention for the manufacture of a medicament (e.g., for the treatment of breast cancer).
[0042] The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. This invention encompasses all combinations of preferred aspects of the invention noted herein. It is understood that any and all embodiments of the present invention may be taken in conjunction with any other embodiment or embodiments to describe additional more preferred embodiments. It is also to be understood that each individual element of the preferred embodiments is intended to be taken individually as its own independent preferred embodiment. Furthermore, any element of an embodiment is meant to be combined with any and all other elements from any embodiment to describe an additional embodiment.
DEFINITIONS
[0043] The examples provided in the definitions present in this application are non-inclusive unless otherwise stated. They include but are not limited to the recited examples.
[0044] The compounds of the present invention may have asymmetric centers. Compounds of the present invention containing an asymmetrically substituted atom may be isolated in optically active or racemic forms. It is well known in the art how to prepare optically active forms, such as by resolution of racemic forms or by synthesis from optically active starting materials. All processes used to prepare compounds of the present invention and intermediates made therein are considered to be part of the present invention. All tautomers of shown or described compounds are also considered to be part of the present invention.
[0045] “Host” preferably refers to a human. It also includes other mammals including the equine, porcine, bovine, feline, and canine families.
[0046] “Treating” or “treatment” covers the treatment of a disease-state in a mammal, and includes: (a) preventing the disease-state from occurring in a mammal, in particular, when such mammal is predisposed to the disease-state but has not yet been diagnosed as having it; (b) inhibiting the disease-state, e.g., arresting it development; and/or (c) relieving the disease-state, e.g., causing regression of the disease state until a desired endpoint is reached. Treating also includes the amelioration of a symptom of a disease (e.g., lessen the pain or discomfort), wherein such amelioration may or may not be directly affecting the disease (e.g., cause, transmission, expression, etc.).
[0047] “Therapeutically effective amount” includes an amount of a compound of the present invention that is effective when administered alone or in combination to treat the desired condition or disorder. “Therapeutically effective amount” includes an amount of the combination of compounds claimed that is effective to treat the desired condition or disorder. The combination of compounds is preferably a synergistic combination. Synergy, as described, for example, by Chou and Talalay, Adv. Enzyme Regul. 1984, 22:27-55, occurs when the effect of the compounds when administered in combination is greater than the additive effect of the compounds when administered alone as a single agent. In general, a synergistic effect is most clearly demonstrated at sub-optimal concentrations of the compounds. Synergy can be in terms of lower cytotoxicity, increased antiviral effect, or some other beneficial effect of the combination compared with the individual components.
[0048] “Pharmaceutically acceptable salts” refer to derivatives of the disclosed compounds wherein the parent compound is modified by making acid or base salts thereof. Examples of pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of the basic residues. The pharmaceutically acceptable salts include the conventional quaternary ammonium salts of the parent compound formed, for example, from non-toxic inorganic or organic acids. For example, such conventional non-toxic salts include, but are not limited to, those derived from inorganic and organic acids selected from 1, 2-ethanedisulfonic, 2-acetoxybenzoic, 2-hydroxyethanesulfonic, acetic, ascorbic, benzenesulfonic, benzoic, bicarbonic, carbonic, citric, edetic, ethane disulfonic, ethane sulfonic, fumaric, glucoheptonic, gluconic, glutamic, glycolic, glycollyarsanilic, hexylresorcinic, hydrabamic, hydrobromic, hydrochloric, hydroiodide, hydroxymaleic, hydroxynaphthoic, isethionic, lactic, lactobionic, lauryl sulfonic, maleic, malic, mandelic, methanesulfonic, napsylic, nitric, oxalic, pamoic, pantothenic, phenylacetic, phosphoric, polygalacturonic, propionic, salicyclic, stearic, subacetic, succinic, sulfamic, sulfanilic, sulfuric, tannic, tartaric, and toluenesulfonic.
EXAMPLES
[0049] Table 1 provides compounds that are representative examples of the present invention. When one of R 1 -R 19 is present, it is selected from H or D.
[0000]
1
2
3
4
5
[0050] Table 2 provides compounds that are representative examples of the present invention. Where H is shown, it represents naturally abundant hydrogen.
[0000]
6
7
8
9
10
[0051] 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 that as specifically described herein.
|
The present application describes deuterium-enriched larotaxel, pharmaceutically acceptable salt forms thereof, and methods of treating using the same.
| 2
|
FIELD OF THE INVENTION
The present invention relates to an improved control system in a subterranean well. Particularly, but not exclusively the present invention relates to improved control system for controlling a plurality of tools, equipment and apparatus which are positioned in a subterranean well.
BACKGROUND TO THE INVENTION
Directional drilling has made the extraction of hydrocarbons from small reservoirs economically viable because the borehole can be directed in three dimensions through a number of pockets of hydrocarbons.
The hydrocarbons contained in each of these reservoirs flows through a production tube to the surface. Balanced fluid or optimised flow regimes are designed to intend to get the flow from the reservoirs to the surface as quickly as possible and maximise the amount of hydrocarbons extracted from each reservoir. These flow regimes may dictate that the different reservoirs be emptied at different times. The flow of hydrocarbons from a reservoir into the production tube is controlled using downhole tools such as valves. Downhole valves are, generally speaking, hydraulically controlled.
Hydraulic systems are used to control the operation of tools positioned in the well and can comprise surface equipment such as a hydraulic tank, pump etc and control lines for connecting the surface equipment to the downhole tools. The control lines can be connected to one or more downhole tools.
Several basic arrangements of hydraulic control lines are used in a well. In a direct hydraulic arrangement, each tool that is to be controlled will have two dedicated hydraulic lines. The “open” line extends from the surface equipment to the tool and is used for transporting hydraulic fluid to the downhole control valve to operated the tool, while the “close” line extends from the tool to the surface equipment and provides a path for returning hydraulic fluid to the surface. The practical limit to the number of tools that can be controlled using the direct hydraulic arrangement is three, that is six separate hydraulic lines, due to the physical restraints in positioning hydraulic lines in a well. The tubing hanger through which the hydraulic lines run also has to accommodate lines for a gauge system, at least one safety valve and often a chemical injection line, which limits the number of hydraulic lines the hanger can accommodate.
When it is desirable to control more than three tools in a well, a common close arrangement can be employed in which an open line is run to each tool to be controlled and a common close line is connected to each tool to return hydraulic fluid to the surface. The common close system has a practical limit of controlling five tools through the six separate hydraulic lines.
In another arrangement, a single hydraulic line is dedicated to each tool and is connected to each tool via a separate, dedicated controller for each tool. To open the tool, the hydraulic fluid in the dedicated line is pressurised to a first level. Thereafter, the hydraulic fluid in the dedicated line is pressurised to a higher level so as to close the tool.
In a digital hydraulics system, two hydraulic lines are run from the surface equipment to a downhole controller that is connected to each of the tools to be controlled. Each controller is programmed to operate upon receiving a distinct sequence of pressure pulses received through these two hydraulic lines. Each tool has another hydraulic line is connected thereto as a common return for hydraulic fluid to the surface. The controllers employed in the single line and the digital hydraulics arrangements are complex devices incorporating numerous elastomeric seals and springs, which are subject to failure. In addition, these controllers used small, inline filters to remove particles from the hydraulic fluid that might otherwise contaminate the controllers. These filters are prone to clogging and collapsing. Further, the complex nature of the pressure sequences requires a computer operated pump and valve manifold, which is expensive.
An alternative, simpler arrangement which can be used to operate a large number of tools has been proposed utilising RFID tags to activate downhole tools. The RFID tags are programmed with a message for a specific downhole tool. The tag is sent down a control line which runs adjacent the tools. The control line includes a tag reader for each downhole tool, each reader reading the message on the tag as it passes. When the reader associated with the tool the message is intended for reads the tag, the message is relayed to the tool control and the instruction is carried out. The instruction may be to open a valve to allow hydrocarbons to flow into the production tube. Such a system requires a common open line running to all tools, a common close line running to all tools and a tag line down which the RFID tags can be flowed down.
The drawback of such a system is the requirement for power to be continuously supplied to the readers to detect the presence of a tag and then to provide power to the control system to actuate the specific tool. The power is generally provided by batteries. As these batteries are continually supplying power the downhole readers, they can be drained over a period of 2 to 3 weeks and require replacement which can be an extremely expensive and time consuming process.
SUMMARY OF THE INVENTION
According to a first aspect of the present invention there is provided an improved control system for use in a subterranean well, the system comprising:
at least one apparatus positioned within the subterranean well;
at least one power generation device positioned within the subterranean well, the at least one power generation device adapted to supply electrical power to the at least one apparatus; and
at least one control line positioned in the subterranean well, the at least one control line adapted to supply a hydraulic pressure applied from surface to the at least one power generation device from which the at least one power generation device generates electrical power.
In one embodiment, the present invention provides a control system for use in a subterranean well which includes a power generation device, which generates electrical power in response to the application of hydraulic pressure from surface. As electrical power can be generated by the power generation device as and when required, the downhole life of such a system is extended.
The/each power generation device may be adapted to supply electrical power to more than one downhole apparatus. In one embodiment a power generation device may power an RFID tag reader and a downhole tool such as a valve.
The/each power generation device may be adapted to supply electrical power to an energy storage device such as a battery, a capacitor, a spring, a compressed fluid device such as a gas spring or the like.
In an alternative embodiment, the/each power generation device may be adapted to supply electrical power to a drive means to raise a weight against gravity. Energy would be stored in such a device, which can be harnessed by allowing the weight to fall under the influence of gravity.
In one embodiment, the power generation device converts the applied hydraulic pressure in to linear motion.
Preferably, the power generation device comprises a piston to convert the applied hydraulic pressure in to linear motion.
In one embodiment, the power generation device is further adapted to convert the linear motion into rotary motion. The power generation device may include a ball screw or rack and pinion for this purpose.
In an alternative embodiment, the power generation device is adapted to convert the applied hydraulic pressure in to rotary motion.
Preferably, the power generation device is adapted to convert rotary motion to electrical power. The power generation device may include a generator for this purpose. The generator may be a dynamo. A dynamo can generate AC or DC power.
In one embodiment, in which the power generation device produces AC power, the control system further comprises a rectifier or switch mode regulator. A rectifier or switch mode regulator converts an AC input into a DC output.
The power generation device may include a biasing means adapted to resist the application of hydraulic pressure.
In one embodiment in which the power generation device converts the applied hydraulic pressure in to linear motion using a piston, the piston is moveable between a first position and a second position and comprises a biasing means to bias the piston to the first position. In this embodiment, the hydraulic pressure moves the piston against the biasing means to the second position, generating linear motion. Once the applied hydraulic pressure is removed the biasing means returns the piston to the first position generating further linear motion which is, in turn, converted into electrical power.
The biasing means may comprise a compression spring, a wind up spring, a coil spring, a leaf spring, a gas spring, well pressure, a suspended weight or the like.
Alternatively, downhole pressure could be utilised to provide the biasing means or to return the piston to the first position.
In a further alternative, a second control line may be provided in the well to provide the biasing means or to return the piston to the first position.
According to a second aspect of the present invention there is provided a method of controlling at least one apparatus positioned within a subterranean well, the method comprising the steps of:
applying a hydraulic pressure from surface to a power generation device, the power generation device adapted to convert the applied force into electrical energy, the electrical energy being used to control at least one apparatus positioned within the subterranean well.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described with reference to the accompanying drawings in which:
FIG. 1 is a section view through a subterranean well showing a control system according to a first embodiment of the present invention;
FIG. 2 is a schematic of the control system of FIG. 1 ;
FIG. 3 is a schematic of the power generation device of the system of FIG. 1 ;
FIG. 4 is a schematic of a control system according to a second embodiment of the present invention;
FIG. 5 is a schematic of a control system according to a third embodiment of the present invention; and
FIG. 6 is a schematic of the power generation device of the system of FIG. 5 .
DETAILED DESCRIPTION OF THE INVENTION
Reference is made to FIG. 1 , a schematic of a control system, generally indicated by reference numeral 10 , according to a first embodiment of the invention.
The control system 10 controls the flow of hydrocarbons from each of four hydrocarbon reservoirs 12 a - d into a production tube 14 which is disposed within a subterranean well 16 , the production tube 14 extending from the reservoirs 12 a - d up to an oil rig 18 . Specifically, the control system 10 controls four downhole tools 20 a - d which permit the hydrocarbons from reservoirs 12 a - d respectively to flow into the production tube 14 .
Referring now to FIG. 2 , a schematic of the control system 10 of FIG. 1 is shown. The control system 10 controls each of the four downhole tools by selectively allowing each tool 20 a - d to be exposed to hydraulic pressure applied through a first hydraulic line 22 and/or a second hydraulic line 24 .
The control system 10 comprises four control system units 26 a - d . Each control system unit 26 a - d comprises a corresponding power generation device 28 a - d , each power generation device 28 a - d adapted to supply electrical power to two apparatus; a corresponding needle valve 30 a - d and a corresponding RFID tag reader 32 a - d.
The control system 10 further comprises a control line 34 which supplies hydraulic pressure from the rig 18 to each of the power generation devices 28 a - d . The third control line 34 includes a valve 33 which can be closed from surface to allow for hydraulic pressure to be built up in the third control line 34 . As will be discussed, each power generation device 28 a - d is adapted to generate power from the applied hydraulic pressure, the generated power being used to operate the corresponding needle valve 30 a - d and/or the corresponding RFID tag reader 32 a - d.
The power generation device 28 shown in FIG. 3 may represent any one of the power generation devices 28 a - d . The power generation device 28 comprises a piston 40 in a housing 42 . The piston 40 is shown in FIG. 3 located in a first position to which it is biased by a compression spring 44 .
The piston 40 is connected to a ball screw device 46 for converting linear motion of the piston 40 into rotary motion. The rotary motion is transferred by a transfer rod 48 to a generator 50 . The generator 50 is connected to a rectifier 52 which produces a direct current, which is supplied to the needle valve (not shown) by a first wire 54 and to the RFID tag reader (not shown) by a second wire 56 .
To operate the power generation device 28 , the third control line valve 33 is closed and hydraulic pressure is applied through the third control line 34 , to the piston 40 . The application of pressure moves the piston 40 towards the ballscrew 46 , against the bias of the compression spring 44 generating electrical power through the generator 50 and rectifier 52 for supply to the needle valve (not shown) and RFID tag reader (not shown).
Once the piston 40 has reached the extent of its travel the hydraulic pressure in the third control line 34 is released by opening the third control line valve 33 , allowing the piston 40 to travel back to the first position. During this return travel more electrical power is generated which the rectifier 52 converts to direct current for supply to the needle valve (not shown) and the RFID tag reader (not shown).
Referring back to FIG. 2 , the operation of the control system 10 will now be described. The objective of the control system 10 is to allow one of the tools 20 a - d to be operated by exposure to hydraulic pressure through one of the first or second control lines 22 , 24 .
In this example, an RFID tag (not shown) is to be sent from the rig 18 with an instruction to operate the third tool 20 c . The third tool 20 c is to be operated by opening the third needle valve 30 c permitting a hydraulic pressure applied by the first control line 22 to be released by activating the tool 20 c.
The first step of this operation is to apply a hydraulic pressure to the third control line 34 to generate power, through the power generation devices 28 a - d to, initially, operate the RFID tag readers 32 a - d , and apply a hydraulic pressure through the first hydraulic line 22 to operate the tool 20 c . The tool 20 c is prevented from operating by the needle valve 30 c which is closed and is containing the pressure.
Once the pistons 40 have reached the extent of their travel the pressure in the third control line 34 is reduced by opening the third control line valve 33 , permitting the pistons 40 to return to their start positions and generate further power. Once the readers 32 a - d are operational and the third control line valve 33 is open, RFID tags containing the message to operate the third tool 20 c are sent down the third control line 34 .
The tag flows down the third control line 34 passing through the four tag readers 32 a - d . The first, second and fourth readers 32 a,b,d will ignore the message on the tag but the third reader 32 c will transfer the message to the needle valve 30 c . Using power generated by the third power generation device 28 c , the needle valve 30 c opens, releasing the hydraulic pressure in the first hydraulic line 22 permitting the tool 20 c to operate.
Reference is now made to FIG. 4 , a schematic of a control system 110 according to a second embodiment of the present invention. This system 110 includes first and second control lines 122 , 124 and is largely similar to the system 10 of the first embodiment, the difference being that each power generation device 128 a - d is operated by the application of hydraulic pressure through the second control line 124 . The operation of the system 110 is otherwise the same.
Reference is now made to FIG. 5 , a schematic of a control system 210 according to a third embodiment of the present invention. This system is largely similar to the system 110 of the second embodiment, the difference being that the power generation devices 228 a - d are connected to both the first and second control lines 222 , 224 . to the power generation device 228 shown in FIG. 6 may represent any one of the power generation devices 228 a - d . From FIG. 6 , it can be seen that the first and second control lines 222 , 224 are fed to either side of the piston 240 . As can be seen from FIG. 6 , there is no biasing spring in the housing 242 , the piston 240 being moved to the left by application of hydraulic pressure through second line 224 , and returned to the start position by the application of pressure through the first hydraulic line 222 .
Various modifications and improvements may be made to the above described embodiments without departing from the scope of the invention. For example, each power generation device may supply power to a battery or other energy storage device for storage until required.
|
A control system for use in a subterranean well comprises at least one power generation device positioned within the subterranean well, the at least one power generation device adapted to supply electrical power to at least one apparatus positioned within the subterranean well and at least one control line positioned in the subterranean well. The at least one control line connects each power generation device to surface and is adapted to supply a hydraulic pressure applied from surface to the at least one power generation device from which the at least one power generation device generates the electrical power to be supplied to the at least one apparatus.
| 4
|
BACKGROUND OF THE INVENTION
I. Field of the Invention
This invention relates generally to a device for converting organic material to a combustible gas, and more particularly to the particular design of a small scale gasifier which successfully obviates many of the problems inherent in prior art gasifier equipment.
II. Discussion of the Prior Art
Gasification, as used herein, refers to the production of combustible gases from solid organic material by the application of heat, i.e., pyrolysis. Gasifiers of the general type involved here have been around for over 200 years. During the Industrial Revolution, large quantities of coal were being coked prior to its use in smelting operations. The gas driven off during the coking process was combustible and was used for gas lighting during the early 1800's. Subsequently, gasifiers were designed for use with internal combustion engines. During World War I, with the blockading of oil imports, the German military utilized bolt-on gasifiers as a fuel source for motor vehicles.
Combustion, for purposes of gasification, can be defined as the chemical reaction between oxygen and an organic fuel, i.e., a fuel in which the element carbon is in its chemical makeup. During combustion, the oxygen chemically combines with the fuel to produce new chemical compounds and it is found that the rate of the reaction is dependent on many factors other than the chemical makeup of the fuel itself. For example, the amount of oxygen reaching the fuel has a great effect on combustion rate as does the amount of heat applied to the fuel to liberate the gases necessary for combustion to take place. Another factor is the physical characteristics of the fuel, i.e., its shape and total surface area exposed to oxygen.
Efficient gasification is also dependent upon the manner in which heat liberated during combustion of the fuel is absorbed by yet uncombusted material. Because heat rises, it follows that uncombusted fuel should be placed above the point where combustion is already underway.
Another variable which will alter or affect the properties of combustion lies in the manner in which the oxidizer is introduced to the fuel. The oxidizer, which is usually air, can be brought to the combustion zone from three main directions, i.e., from below, from above or from the sides. Each direction of air flow is found to exhibit its own particular advantages and disadvantages. The natural flow of air is from below. This is because the gases and smoke created by the fire are hotter than the surrounding atmosphere, and, therefore, lighter. This causes them to rise through the combustion zone which, in turn, draws more air in at the bottom to replace it. The advantage of this natural convection air supply is that it is self-feeding and requires no outside impetus to air movement such as a blower. The drawbacks of the natural flow are that tars and other uncombusted by-products are carried off by the exiting gases and smoke creating pollution problems. The tars and by-products also tend to re-condense on the walls of the gasifier unit requiring periodic shutdown for cleanup. Furthermore, the tar substances passing upward through the fuel mass tends to condense out creating a sticky residue on the fuel, inhibiting its ability to flow.
In an attempt to alleviate or eliminate the tar production problem, a number of prior art gasifiers have been designed which deliver combustion air from the sides. In the single side delivery system, the combustion zone takes on the configuration of an elongated ovoid. This proved to be rather counter-productive, in that the cross-sectional configuration of the containment vessel is most often circular. In practice, it means that some uncombusted feed stock will simply move past the sides of the combustion zone and fall into the ash pit. Later, modifications were made to bring combustion air in from a number of discrete directions which gives rise to a combustion zone of overlapping ovoids. For example, if air inlets are positioned 60° apart around the periphery of the combustion zone, each air inlet will only carry 16.6% of the air carried by a single inlet. This leads to radically decreased ovoids which barely overlap. The end-result is, again, poor combustion characteristics.
The side delivery designs permit combustion gases to exit through the uncombusted feed stock, which carried off the tars from the partial pyrolysis. It has been determined that tar production ceases above 700° C. Any tars that are produced above that temperature are quickly decomposed into simpler chemical constituents. Thus, tar that is produced in feed-stocks below the 70° C. limit may be broken down at will by the simple expedient of heating the tar above the 70° C. temperature. Perhaps the simplest way of accomplishing this is to bring combustion air into the fire, or gasifier, from the top. The combustion air carries any tar products and vapors along with it directly into the hot combustion zone of the gasifier. The exit for the combustion gases is through the combustion zone and out the bottom of the fire.
Another problem extant in prior art gasifier designs involves "bridging" where the incoming feed stock builds up in the combustion zone and does not naturally flow as combustion takes place. The practice in dealing with the fuel bridging problem has been to provide mechanical agitators for stirring up the organic material feed stock and breaking up the bridged fuel so that it can continue to flow into the combustion zone. Such mechanical devices need attention and are also subject to frequent repair and replacement.
A successful gasifier system should exhibit the following characteristics:
1. Zero bridging;
2. Minimal maintenance;
3. Minimal down-time for cleaning and/or ash removal; and
4. Usable generated gas, i.e., no tar, no condensate, no particulate matter, no obnoxious emissions.
The system of the present invention possesses all of the above attributes. It is capable of handling a wide range of feed stocks in terms of types and sizes and requires no operator in attendance. The system is capable of running for prolonged periods without the need for periodic shutdowns. It produces no tar, condensates, hydrocarbons or obnoxious emissions and satisfies all EPA guidelines. The invention presents no bridging or feeding problems and drastically reduces clean-up and ash handling. The gasifier itself is totally self-cleaning and all ash generated is deposited in a receptacle without recourse to augers or mechanical devices of any kind. The system of the present invention does not require any down-stream gas clean-up apparatus in that the generated gases are ready to use as they are generated.
SUMMARY OF THE INVENTION
The foregoing features and advantages of the invention are achieved by providing a cylindrical tank body having bottom and side walls consisting of a stainless steel outer jacket, a stainless steel inner jacket and a suitable high temperature insulation material disposed between the two concentric jackets. A refractory brick may also be used to line the interior of the gasifier, both on its bottom and its cylindrical side walls. Projecting from the top of the cylindrical body is a frustoconical feed hopper assembly which also is fabricated from outer and inner stainless steel walls separated by a high temperature insulation. The top of the truncated cone is open and it is through this opening that the organic fuel material is fed.
Located within the cylindrical tank body and inverted beneath the top feed hopper cone is a hearth cone assembly which is bolted to the feed hopper. 8urrounding the base of the feed hopper is an air inlet manifold communicating with a plurality of equally spaced radial holes formed through the base of the conical feed hopper. The incoming air along with the feed stock thus flows through the inverted cone to the combustion zone. In that the hearth cone causes a throttling of the air, its velocity is increased which aids combustion.
A grate assembly is disposed a predetermined distance beneath the throat of the inverted truncated hearth cone member and comprises a pyramidal arrangement of concentric rings which are welded to four main support bars and four intermediate support bars which combine to give the grate its conical profile when viewed from the side. The grate supports the fuel as it is being burned in a controlled oxygen supply environment in an equally distributed fashion.
Located directly beneath the conical grate is a conical baffle which causes the burning fuel particles dropping through the grate to flow toward the walls of the gasifier and from their falling into an ash disposal compartment located at the gasifier body's base. Beneath the conical baffle is a series of three more vertically disposed baffles, each of which comprises an outer cylinder concentric with an inner cylinder and having a series of spiral vanes extending from the outer periphery of the inner cylinder to the inner periphery of the outer cylinder.
Near the base of the gasifier body or tank is a gas outlet connection and this outlet connection is coupled to a vane axial fan or blower. When the blower is operational, it draws outside air through the air manifold surrounding the fuel hopper, through the fuel in the hopper and it moves with an increased velocity through the fuel which is supported by the conical grate. The subsequent passage of the air through the baffles causes the particulate matter (ash) to be steered to a point where it falls into an ash receptacle while the additional baffles create substantial turbulence which reduces the remaining ash particles present in the gas stream to micron size where they become suspended in the exit gas and are effectively burned in the end use device for which the gas is being generated. The baffles perform a further function of increasing the dwell time that the gas remains in the high temperature zone of the gasifier. This increased resident time provides ample time to break down toxic chemicals such as dioxens which may be present in the fuel.
By providing an air intake control, the pyrolysis takes place in a starved oxygen environment insuring that no flame will be present within the gasifier unit itself. The design of the fuel hopper and the grate as well as the relative positioning of the grate relative to the opening in the fuel hopper insures that no bridging of the fuel takes place. Moreover, because the air flow is from top to bottom, tars, creosol and other debris boiled from the fuel does not pass up through the entering fuel supply to create a sticky mass which, as mentioned earlier, was a drawback of certain prior art designs.
OBJECTS
It is accordingly a principal object of the present invention to provide a new and improved gasifier for producing a combustible fuel from organic materials.
Another object of the invention is to provide a gasifier device which obviates problems encountered in prior art designs.
Another object of the invention is to provide a gasifier which requires low maintenance and no full-time operator attendance.
Still another object of the invention is to provide a gasifier unit which is highly efficient in its operation and which is capable of meeting existing EPA regulations relating to air pollution.
A further object of the invention is to provide a continuous feed gasifier in which problems due to fuel bridging are obviated.
A still further object of the invention is to provide a small-scale, low-cost gasifier unit which produces a clean, combustible gas suitable for direct use in many applications without the need for further cleaning procedures.
These and other objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description of a preferred embodiment, especially when considered in conjunction with the accompanying drawings in which like numerals in the several views refer to corresponding parts.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the gasifier unit of the present invention;
FIG. 2 is a cross-sectional view of the unit of FIG. 1;
FIG. 3 is a top view of the grate assembly used in the preferred embodiment; and
FIG. 4, is a side, partially cross-sectional view of the grate of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, there is illustrated a side elevation view of the gasifier embodying the principles of the present invention. The gasifier assembly is indicated generally by numeral 10 and includes a cylindrical tank 12 as a body member which is mounted on a base 14 supported by beams 16. The beams 16 may be a part of a trailer bed for a movable installation or may be stationary. Also mounted on the bed 16 is a motor-driven vane axial blower 18 whose inlet is coupled through suitable duct work 20 to a flange 22 on the gasifier's outlet port 24. The outlet 26 of the blower 18 is coupled through suitable duct work 28 to a gas utilization device, such as a furnace or an internal combustion engine (not shown). Also joined to the gas discharge outlet ductwork 28 is a vent stack 30 having a automatically controlled valve 32 in line with it. As will be pointed out below, the control valve 32 is a safety device allowing the volatile gas generated by the gasifier 12 to be vented to the atmosphere rather than being delivered to the utilization device should, for example, an over-temperature condition develop.
Bolted to the upper end of the cylindrical body 12 is a fuel inlet hopper 34 in the form of a truncated cone. Fuel, such as wood chips, sawdust briquettes, briquetted animal waste, etc., is fed into the gasifier assembly 10 by means of an infeed auger, only a portion of which is shown in FIG. 1 and is identified by numeral 36. The augered fuel drops through an inlet stack 38 and through the open top of the frusto-conical shaped fuel infeed hopper 34. Also attached to the upper end of the body member 12 and surrounding the hopper 34 is an annular combustion air manifold 40.
Referring next to the cross-sectional view of FIG. 2, it can be seen that the body member 12 includes an inner cylinder 44 which is surrounded on the outside by a ceramic sleeve 46 and which is lined on its inner surface with refractory brick or a ceramic insulation layer. This combination of materials adequately insulates the body 12 so that the outer surface of the body will be safe to touch and so the heat generated during combustion will be contained within the gasifier to increase the conversion efficiency. Typically, the refractory layer 48 and the ceramic layer 46 may each be approximately three inches in thickness.
In a similar fashion, the base 14 comprises first and second circular steel plates 50 and 52 separated by a high temperature ceramic 54 with the upper stainless steel plate 52 also supporting a refractory brick liner 56. Thus, the body member and base are configured to avoid substantial heat loss therethrough.
The infeed hopper 34 is provided with a plurality of air intake ports formed radially 360° around the base thereof and within the confines of the air intake manifold 40. Collectively, the area of the radial air inlet ports 58 equals or exceeds the area of the gas exit port 24 and the air inlet port 42. The infeed hopper 34 is also preferably fabricated from a suitable metal, such as stainless steel, and may be covered with a ceramic layer 60 to limit heat loss therethrough.
The frusto-conical infeed hopper 34 has an annular flange 62 surrounding its base and this flange is joined to a corresponding annular flange 64 formed around the upper periphery of an inverted frusto-conical member 66 which projects downwardly into the interior of the body member 12. The cone 66 converges to a hearth throat 68 located a predetermined distance above a primary grate 70. As can best be seen in FIGS. 3 and 4, this grate comprises a series of concentric rings 72, 74, etc., supported by four radially extending support bars 76 disposed at 90° intervals. Intermediate supports 77 are interposed midway between the main support bars and, like the main support bars, are welded to the rings 72, 74, etc. Because of the temperatures encountered, it has been found expedient to fabricate the grate rings and supports from type 304 stainless steel, but limitation thereto is not required. As can also be seen in FIG. 4, the support rods 76 and 77 are sloped outwardly and downwardly such that the spaced concentric rings 72, 74, etc., assume a pyramidal configuration. The concentric rings are spaced in such a manner as to block any uncombusted feed stock above a predetermined size from falling through. It is further contemplated that the grate can be fabricated using a supported spiral of titanium wire in place of the stainless steel rings.
The conically-shaped grate 70 is preferably mounted within the body member 12 so as to be vertically positionable whereby the distance between the grate and the throat 68 of the hearth cone 66 can be adjusted to accommodate different fuels. In this regard, the grate may be suspended from the flange surrounding the lower base of the infeed hopper by threaded rods as at 75 (FIG. 4).
Positioned below the grate 70 are a plurality of baffle members including a primary baffle 78. This baffle has a stainless steel surface 79 which slopes at an angle of about 25° to the horizontal and it results in the diversion of fuel particles falling through the grate to the peripheral edge thereof. Baffle 78 is suspended from the body's side walls by pins (not shown) which leaves a gap between the peripheral edge of the baffle and the I.D. of the body through which fuel particles and ash may fall. Located beneath the conical baffle 78 are a series of three additional baffles 80, 82 and 84, each of which comprises a base plate, an outer cylinder 86 concentric with an inner cylinder 88 and a series of spiral veins which extend from the outer periphery of the inner cylinder 88 to the inner periphery of the outer cylinder 86 so as to create an elongated, torus path to the flow of the combustible gases therethrough. More specifically, baffle 80 has its vanes configured to route the gases generated from the outer edge of baffle 78 to a center opening in the base plate of baffle 80. This has the effect of creating a whirling motion to the gas stream and to increase its velocity. Baffle 82 has no central opening and collects the bases exiting the center of baffle 80. Its vanes direct the gas flow to its outer periphery. In doing so, the gas velocity again decreases. Baffle 84 is similar in design to baffle 80 and again steers the gases to a center opening in its base plate again increasing the gas velocity. Located beneath the lowermost baffle 84 is the gas outlet manifold 90 to which the gas outlet port 24 connects.
Drilled through the base of baffle 80 is a drain hole and screwed into this drain hole is a drain assembly 92 comprising a 45° elbow 94 and an extension pipe passing through the walls of the body 12. Materials, such as glass and non-ferrous metals, contained within the fuel mass are melted in the gasifier and are separated and drained away through the assembly 92.
Having described the general construction of the gasifier in accordance with the present invention, consideration will next be given to its operation.
OPERATION
The organic fuel to be gasified is augered into the fuel hopper 34 on a continuous basis and it is made to fall into the hearth cone 66 where it is mixed with combustion air drawn by the blower 18 through the air inlet 42 and thence through the radial apertures 58 extending through the base portion of the feed hopper 34. The hearth cone 66 is provided to direct the combustion products to the hearth throat 68. Preliminary combustion begins in the interior of the hearth cone 66 with the heat of combustion initiating the pyrolysis process in the as yet uncombusted feed stock. The products of this pyrolysis include carbon dioxide, carbon monoxide, hydrogen, CH 4 , tars and water vapor.
At the throat 68, the combusting solid organic fuel is guided onto the grate 70. At the same time, the conical constriction in the cross-sectional area functions to increase the gas velocity which thus cooperates to contribute to a high temperature area in and under the throat. By appropriately designing the taper of the hearth cone 66 to approximately 50° to the horizontal, the diameter of the opening defining the throat 68 and the height of the throat 68 above the grate 70, the combusting fuel can be made to uniformly distribute over the surface of the grate 70. The hot coals supported on the grate 70 are held there to insure full combustion of the feed stock and to further the conversion of non-combustible carbon dioxide to combustible carbon monoxide. The finer fuel particles capable of falling through the spacing between the grate rings arrive on the primary baffle 78 where non-combustible CO 2 is further converted to combustible CO in the presence of glowing carbon coals and this conversion process is carried out in direct proportion to the time that the carbon dioxide remains in contact with the coals. The baffle 78 also increases the length of the flow path of the exiting gases to increase their resident time within the gasifier which enhances the conversion process. Moreover, the restriction introduced by the baffle increases the velocity of the gases to assist in lifting and carrying of fine cinders and flyash with the gas flow. The further baffles 80, 82 and 84 also serve to increase the residence time of the fine solid fuel particles within the gasifier and the swirling action introduced to the gas stream by the spiral vanes contained within the baffles assists in keeping the baffles and other surfaces impinged upon by the gas flow clean. It is found that the turbulence reduces the flyash to micron size which allows it to be carried with the gas stream, obviating the need for expensive equipment which had to be used with prior art systems to separate out the larger size ash particles from the usable fuel.
The negative taper of the feed cone 66 together with the down drafting resulting when the axial vane blower 18 is coupled to the gas outlet port at the base of the gasifier unit with combustion air being introduced near the top of the body 12 is found to essentially eliminate tar production. Moreover, the tendency for feed stock bridging has been eliminated without the need for complex shakers and mechanical agitators to maintain the continuous flow of fuel into the combustion zone.
Because of the negative down-draft design inherent in the gasifier of the present invention, all hydrocarbons are brought down through the high temperature grate zone and are effectively "cracked" into carbon and various gases.
This invention has been described herein in considerable detail in order to comply with the Patent Statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to equipment details and operating procedures, can be accomplished without departing from the scope of the invention itself.
|
A gasifier for converting solid organic fuels to combustible gas includes a cylindrical body having insulated side walls and a gas outlet port near its base. Affixed to the top of the cylindrical tank is a conical-shaped fuel feed hopper and beneath it and within the interior of the tank is an inverted truncated one. Positioned beneath the throat of the inverted cone is a pyramidal-shaped grate for supporting the combusting solid fuel during the inversion process. Positioned beneath the grate are a series of baffles. Combustion air is drawn in through the upper portion of the tank near the base of the frusto-conical feed hopper by the action of a motor-driven fan coupled to the gasifier's outlet port. The down draft gas flow reduces noxious fumes and pollutants while the baffles, by increasing the fluid velocity of the gases, tends to make the unit self-cleaning. The design of the hearth cone and grate also eliminates bridging of the fuel during the gasification process.
| 2
|
RELATED APPLICATIONS
[0001] There are no previously filed, nor currently any co-pending applications, anywhere in the world.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to filters and, more particularly, to a disposable liner adapted for removable attachment to a conventional lint trap.
[0004] 2. Description of the Related Art
[0005] Lint traps in domestic and commercial clothes dryers are well known. These devices, particularly utilized in automatic clothes dryers, include lint filtering screens which are positioned in the air flow path downstream of a dryer drum in order that moisture-laden lint entrained in the air stream is filtered therefrom prior to the exhaustion of the air from the dryer apparatus.
[0006] Clothes dryer manufacturers generally recommend that lint screens be cleaned preferably after each dryer load, thus requiring lint-laden screens to be laboriously cleaned and frequently replaced. Cleaning necessitates the manual removal of lint from the lint screen which invariably requires numerous attempts due to lint fragmentation and fall-off. However, cleaning of the lint screen is often neglected, thus generating an excessive accumulation of lint on the lint screen. In any event, excessive lint accumulation can impede the normal operation of the clothes dryer. Excessive lint accumulation can further cause lint to rub on the exhaust chute during removal of the screen and fall therefrom into the dryer drum atop a freshly laundered load. Moreover, lint accumulation can cause lint particles to scatter or disperse into the surrounding environment thus inducing respiratory problems and fire hazard.
[0007] Accordingly, a need has arisen for a disposable filter media being removably attachable to a conventional lint trap which allows lint to be removed monolithically therefrom in a manner which is quick, easy, and efficient. The development of the lint trap liner fulfills this need.
[0008] A search of the prior art did not disclose any patents that read directly on the claims of the instant invention; however, the following references were considered related.
[0009] U.S. Pat. No. 4,653,200, issued in the name of Werner discloses a lint screen shield assembly attached to a removable dryer lint screen.
[0010] U.S. Pat. No. 6,481,047 B1, issued in the name of Schaefer discloses a vacuum cleaner device for cleaning lint from lint traps of clothes dryers.
[0011] U.S. Pat. No. 4,720,925, issued in the name of Czech et al. discloses a lint filter housing for a dryer.
[0012] U.S. Pat. No. 5,236,478, issued in the name of Lewis et al. discloses a lint trap unit which emphasizes drastically reduced air flow within the cabinet of the dryer unit preceding an incorporated filter tray, when employed, so as to allow for an effectual precipitation on entrained moisture, lint, and other particles to the bottom of the container.
[0013] U.S. Pat. No. 5,042,170, issued in the name of Hauch et al. discloses a lint collecting device particularly suited for use in conventional domestic clothes dryers.
[0014] U.S. Pat. No. 3,648,381, issued in the name of Fox discloses a lint trap located on the door of a clothes dryer.
[0015] U.S. Pat. No. 4,115,485, issued in the name of Genessi discloses a lint interceptor for separating lint from a stream of air emanating from a clothes dryer.
[0016] U.S. Pat. No. 7,055,262 B 2 , issued in the name of Goldberg et al. discloses a drying apparatus comprising a chamber for containing articles to be dried, means for supplying heated dry air at a first temperature to the chamber, which air supplying means comprises an air flow pathway having means for removing moisture from air exiting the chamber and for decreasing the temperature of the air to below dew point temperature and means for increasing the temperature of the air exiting the moisture removing means to the first temperature, and a heat pump system.
[0017] Consequently, a need has been felt for a disposable filter media adapted for removable attachment to a conventional lint trap which allows lint to be removed unitarily therefrom in a manner which is quick, easy, and efficient.
SUMMARY OF THE INVENTION
[0018] Therefore, it is an object of the present invention to provide a disposable filter media adapted for removable attachment to a conventional lint trap used in automatic clothes dryers.
[0019] It is another object of the present invention to provide a disposable filter media in the form of a flexible, lightweight liner comprised of a meshed membrane adapted for snug, contiguous placement atop the lint collecting surface of a screen web of a lint trap.
[0020] It is another object of the present invention to provide a meshed membrane constructed of a material having a mesh size adapted to facilitate optimum lint capturing efficiency without an inordinate drop in the air volume in a clothes dryer.
[0021] It is another object of the present invention to provide an integral attachment means adapted to facilitate removable attachment of lint trap liner to lint trap.
[0022] It is still another object of the present invention to provide a plurality of linearly aligned lint trap liners which are formed, manufactured, packaged, and provided in a rolled form for ease of dispensing and use.
[0023] Briefly described according to one embodiment of the present invention, a lint trap liner is disclosed. The lint trap liner is adapted for removable attachment to a conventional lint trap utilized for filtering lint in automatic clothes dryers. The lint trap liner is adapted for disposable use and forms a generally rectangular configuration having an upper surface or lint contacting surface and a lower surface. The lint trap liner is adapted to capture moist lint from a stream of air exhausted from the air outlets through the exhaust chute of a clothes dryer as lint passes therethrough.
[0024] The lint trap liner comprises an elongated, flexible, tenuous meshed membrane adapted for snug, contiguous placement atop the lint collecting surface of a screen web of a lint trap. The meshed membrane is constructed of a material having a porosity or mesh size adapted to facilitate optimum lint capturing efficiency without an inordinate drop in the air volume in the clothes dryer.
[0025] An attachment means is provided in order to facilitate removable attachment of lint trap liner to lint trap. The attachment means, according to a first embodiment, comprises a plurality of tabs protruding integrally from a continuous peripheral edge of the meshed membrane. The tabs are bent in a manner so as to fixedly engage the underside of corresponding frame peripheral edge portions, thereby removably attaching liner to the lint collecting surface of screen web in a snug-fit manner.
[0026] The attachment means, according to a second embodiment, comprises a plurality of adhesive strips bonded about horizontal and vertical edges of the lint trap liner. Each adhesive strip of the plurality of adhesive strips comprises an adhesive coating bonded to the lower surface of the lint trap liner about a first horizontal edge, a second horizontal edge, a first vertical edge, and a second vertical edge of thereof. The adhesive coating is protected by a releasable liner. The adhesive strips are adapted to releasably hold the liner securely to the front side of the frame of the lint trap.
[0027] The attachment means, according to a third embodiment, comprises at least one catch assembly, wherein catch assembly comprises a pair of opposing L-shaped legs molded integral to the lower surface of lint trap liner about the horizontal sidewalls thereof. The L-shaped legs are adapted to snap into engagement with corresponding rectangular projections formed integral to the lint trap frame by a resilient, snap-fit action, thereby removably securing lint trap liner to lint trap.
[0028] It is envisioned that a plurality of linearly aligned lint trap liners are formed, manufactured, packaged, and provided in a rolled form for ease of dispensing and use. The lint trap liner is manufactured as a length of a plurality of lint trap liners which are perforated at regular intervals, along perforations. An individual lint trap liner is easily separated from the roll along a perforation, in a manner similar to separating a paper towel from a paper towel roll.
[0029] The use of the present invention allows lint to be peelably removed unitarily from a conventional lint trap in a manner which is quick, easy, and efficient. The use of the present invention also eliminates messy cleanup of airborne lint fibers and reduces fire risk.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:
[0031] FIG. 1 is a perspective view of a clothes dryer;
[0032] FIG. 2 is a perspective view of a clothes dryer partially cut away to illustrate the interior components thereof;
[0033] FIG. 3 is a fragmentary view showing a lint trap being removed from the clothes dryer of FIG. 2 ;
[0034] FIG. 4 is a top side view of a conventional lint trap;
[0035] FIG. 5 is a bottom side view of a conventional lint trap;
[0036] FIG. 6 is a side elevational view of a conventional lint trap;
[0037] FIG. 7 is a perspective view of the lint trap liner, according to the preferred embodiment of the present invention;
[0038] FIG. 8 is a cross-sectional view of the lint trap liner illustrating adhesive bonded to the lower surface thereof, according to the preferred embodiment of the present invention;
[0039] FIG. 9 is a top plan view of the lint trap liner illustrating the concave protrusions thereof;
[0040] FIG. 10 is a top plan view of a lint trap liner, according to a first alternative attachment means;
[0041] FIG. 11 is a bottom plan view of the lint trap liner, according to the first alternative attachment means;
[0042] FIG. 12 is a bottom side perspective view of a lint trap showing the lint trap liner removably attached thereto, according to the first alternative attachment means;
[0043] FIG. 13 is a top side perspective view of the lint trap depicted in FIG. 12 showing the lint trap liner removably attached thereto, according to the preferred embodiment of the present invention;
[0044] FIG. 14 illustrates a second alternative attachment means;
[0045] FIG. 15 illustrates a third alternative attachment means; and
[0046] FIG. 16 is a perspective view of a plurality of the lint trap liner depicted in FIG. 14 , positioned into a roll with perforations at regular intervals to provide individual lint trap liners adapted to be separated from the roll.
DESCRIPTION OF THE PREFERRED EMBODIMENT
1. Detailed Description of the Figures
[0047] Referring now to FIGS. 1 and 2 , a clothes dryer 10 is shown and described generally as having a housing 12 and a front, openable loading door 14 with a handle 15 . The door 14 provides access to the interior of a rotatable drum 23 . The rotatable drum 23 rotates about a horizontal axis and has a non-rotating rear bulkhead 25 provided with air inlets 26 and air outlets 27 . The air inlets 26 are adapted for loading the interior of rotatable drum 23 with heated air via a heater 21 and the air outlets 27 are adapted for exhausting moisture, lint laden air. The rotatable drum 23 rotates via an electric motor 28 being operatively connected therewith. The electric motor 28 may also drive a fan 29 in order to facilitate airflow through the interior of rotatable drum 23 .
[0048] The clothes dryer 10 further includes a front wall 19 and a top wall 16 having a control panel 18 at a rear thereof. The control panel 18 includes a plurality of controls 20 , a number of which being manually activated to cause the clothes dryer 10 to advance through an automatic series of drying steps. The top wall 16 has a hatch 22 providing access to a lint trap 30 , shown in FIGS. 1 and 2 . The lint trap 30 is located downstream of the air outlets 27 and is removably held within an exhaust chute 24 . The lint trap 30 is inserted and removed from exhaust chute 24 through an opening 16 a defined in the top wall 16 of clothes dryer 10 . The opening 16 a provides direct passage into the exhaust chute 24 .
[0049] Referring now to FIGS. 3-6 , the lint trap 30 is shown and described generally as having an elongated frame 32 on which is mounted a screen web 90 for collecting lint 40 . The frame 32 includes a front side 32 a , to which is mounted screen web 90 , opposing a rear side 32 b. The screen web 90 forms a lint collecting surface 94 on a first side 92 thereof. Screen web 90 includes a second side 93 opposing the first side 92 . The screen web 90 may define a concave curvature 96 that forms a recessed cavity 98 . The frame 32 further includes an anterior end 33 and a posterior end 34 , wherein anterior end 33 defines a neck portion 37 having a handle 36 integrally molded or suitably affixed, such as by a spacer 38 , thereto. The frame 32 may include a row of spaced, rectangular projections 42 integrally molded to the rear side 32 b thereof. The projections 42 add structural rigidity to the frame 32 and spacings between projections 42 allow frame 32 to bend.
[0050] Referring now more specifically to FIGS. 7 and 8 , a lint trap liner 60 is provided, wherein lint trap liner 60 is adapted for releasable attachment to a lint trap 30 . The lint trap liner 60 is adapted for disposable use and forms a generally rectangular configuration having an upper surface or lint contacting surface 69 and a lower surface 67 . While lint trap liner 60 is described as having a generally rectangular configuration, other geometric configurations are envisioned in order that lint trap liner 60 may shapely and measurably correspond to lint traps 30 defining various other configurations such as circular, square, oval, and the like. The lint trap liner 60 is adapted to capture moist lint 40 from a stream of air exhausted from the air outlets 27 through the exhaust chute 24 of a clothes dryer 10 as lint 40 passes therethrough. The lint trap liner 60 comprises an elongated, flexible, tenuous meshed membrane 62 adapted for snug, contiguous placement atop the first side 92 or lint collecting surface 94 of screen web 90 . The meshed membrane 62 is sizably and flexibly adapted so as to accommodate and readily conform to the contour of the first side 92 of screen web 90 . The meshed membrane 62 is sized so as to extend across an entirety of the first side 92 of screen web 90 . The meshed membrane 62 is constructed of a material having a porosity or mesh size adapted to facilitate optimum lint capturing efficiency without an inordinate drop in the air volume in the clothes dryer 10 . The membrane 62 construction material is adapted to prevent lint 40 fibers from dissociating, scattering or dispersing from atop the lint contacting surface 69 once accumulated thereon. It is envisioned that meshed membrane 62 is fabricated of a high temperature-resistant, flexible media selected from the group which includes but is not limited to monofilament open mesh fabric, fiberglass mesh media, polyethylene and polypropylene blend mesh media, aluminum mesh, and electrostatic mesh media. Monofilament open mesh fabrics comprise polypropylene monofilament fabric and polyester monofilament fabric. The meshed membrane 62 has a porosity or mesh size ranging from about 1 to 1000 microns.
[0051] An attachment means 70 is provided in order to facilitate releasable attachment of lint trap liner 60 to lint trap 30 . The attachment means 70 , according to the preferred embodiment, comprises a thin film of adhesive 130 bonded to the lower surface 67 of the lint trap liner 60 , wherein adhesive 130 is bonded or suitably applied to lower surface 67 in such a manner so as to leave meshed openings 62 a of liner 60 uncovered. The adhesive 130 is a pressure-sensitive adhesive further defined as a releasable bond adhesive. More specifically, the adhesive 130 is comprised a formulation having a degree of tackiness sufficient to hold the liner 60 securely to the front side 32 a of frame 32 in addition to secure snug-fit engagement by liner 60 with the first side 92 of screen web 90 , but which also allows liner 60 to be peelably released unitarily or monolithically from lint trap 30 without tearing, ripping, splitting, or the like. The adhesive formulation also provides sufficient tackiness to ensure against undesirable liner 60 release from lint trap 30 as lint trap 30 is inserted, temporarily positioned inside, and removed from exhaust chute 24 .
[0052] It is envisioned that liner 60 may include a plurality of integral concave protrusions 140 extending outwardly from a continuous peripheral edge of meshed membrane 62 , as shown in FIG. 9 . More specifically, a first pair of protrusions 142 , being spatially positioned, extend outward laterally from a horizontally-oriented peripheral edge 65 of liner 60 , while a second pair of protrusions 144 , being spatially positioned, extend outward laterally from an opposing horizontally-oriented peripheral edge 66 of liner 60 . The protrusions 142 , 144 are formed in a symmetric, curvilinear manner. Such liner 60 embodiment includes, as described above, a thin film of adhesive 130 bonded to the lower surface 67 of the lint trap liner 60 , wherein adhesive 130 is bonded or applied to lower surface 67 in such a manner so as to leave meshed openings 62 a of liner 60 uncovered. The lower surface 67 of liner 60 is aligned with and releasably bonded to the first side 92 of screen web 90 . The first and second pair of protrusions 142 and 144 are folded against corresponding, opposing longitudinal sides 35 , 39 of frame 32 along the underside 32 b thereof. The protrusions 142 and 144 are adapted to conform readily to and be releasably held against opposing longitudinal sides 35 , 39 of frame along the underside 32 b thereof, thereby releasably bonding liner 60 in a snug-fit, conformational manner to lint trap 30 .
[0053] Referring now to FIGS. 10-13 , an attachment means 70 , in another embodiment, comprises a plurality of tabs 80 protruding integrally from a continuous peripheral edge of meshed membrane 62 . More specifically, a first set of tabs 81 protrude perpendicularly from a vertically-oriented lower peripheral edge 64 of liner 60 , while a second set of tabs 82 protrude perpendicularly from opposing horizontally-oriented peripheral edges 65 , 66 of liner 60 . A proximal peripheral edge 63 of liner 60 includes opposing tabs 83 a , 83 b protruding perpendicularly therefrom. Tabs 83 a , 83 b protruding along the proximal peripheral edge 63 of liner 60 define a greater length than a length defining remaining tabs 81 and 82 .
[0054] The plurality of tabs 80 are constructed of a resilient, flexible material adapted to bend to a shaped curvature and maintain the shaped curvature in its existing state until manually straightened, bent, or reshaped to an alternative configuration. In use, once liner 60 is properly aligned and placed atop the screen web 90 , the tabs 80 are bent in a manner so as to fixedly engage the underside 32 b of corresponding frame 32 peripheral edge portions, thereby removably attaching liner 60 to the first side 92 of screen web 90 in a snug-fit manner. More specifically, tabs 81 are adapted to bend and fixedly engage the posterior end 34 of frame 32 along the underside 32 b peripheral edge thereof. Tabs 82 are adapted to bend and fixedly engage corresponding, opposing longitudinal sides 35 , 39 of frame 32 along the underside 32 b thereof. Tabs 83 a and 83 b are adapted to bend and fixedly engage the anterior end 33 of frame 32 along the underside 32 b peripheral edge thereof.
[0055] Referring to FIG. 11 , the attachment means 70 , in another embodiment, comprises a plurality of adhesive strips 50 bonded about horizontal and vertical edges of the lint trap liner 60 . More specifically, each adhesive strip 50 of the plurality of adhesive strips 50 comprises an adhesive coating 52 bonded to the lower surface 67 of the lint trap liner 60 about a first horizontal edge 68 a , a second horizontal edge 68 b , a first vertical edge 68 c , and a second vertical edge 68 d of thereof. The adhesive coating 52 is a pressure-sensitive adhesive which is protected by a releasable liner 55 . The adhesive strips 50 are defined of a formulation having a degree of tackiness sufficient to hold the liner 60 securely to the front side 32 a of frame 32 , thereby ensuring snug-fit engagement by liner 60 with the first side 92 of screen web 90 , but which also allows liner 60 to be peelably removed unitarily or monolithically from lint trap 30 without tearing, ripping, or the like. The adhesive formulation also provides sufficient tackiness to ensure against undesirable liner 60 release from lint trap 30 as lint trap 30 is inserted, temporarily positioned inside, and removed from exhaust chute 24 .
[0056] Referring now to FIG. 12 , the attachment means 70 , in still another embodiment, comprises at least one catch assembly 100 , wherein catch assembly 100 comprises a pair of opposing L-shaped legs 102 molded integral to the lower surface 67 of lint trap liner 60 about the horizontal sidewalls 68 a and 68 b thereof. The L-shaped legs 102 each includes a vertical member 103 having a foot portion 104 extending angularly from a lower end thereof at approximately 90°. The L-shaped legs 102 are linearly aligned and each comprises a boss 105 projecting downwardly from the foot portion 104 thereof. The boss 105 forms a projection receiving cavity 110 adapted to frictionally receive a corresponding rectangular projection 42 of the lint trap frame 32 in a snap-fit manner. The L-shaped legs 102 are adapted to snap into engagement with corresponding rectangular projections 42 of the lint trap frame 32 by a resilient, snap-fit action, thereby removably securing lint trap liner 60 to lint trap 30 . More specifically, the lower surface 67 of lint trap liner 60 is engaged against the first side 92 of screen web 90 and the L-shaped legs 102 of liner 60 are snapped into engagement with corresponding rectangular projections 42 of frame 32 .
[0057] It is envisioned other attachment mechanisms and methods such as hook and loop fasteners may be utilized to facilitate removable attachment of lint trap liner 60 to lint trap 30 .
[0058] Referring now to FIGS. 7-14 , and more particularly to FIG. 16 , as will be described in greater detail below, it is envisioned in another embodiment that a plurality of linearly aligned lint trap liners 60 are formed, manufactured, packaged, and provided in a rolled form 122 for ease of dispensing and use. For purposes of disclosing the best available mode concerning this embodiment, and not by way of limitation regarding the functionality or design of the present invention, the lint trap liner 60 is manufactured as a length of a plurality of lint trap liners 60 which are perforated at regular intervals, along perforations 120 . An individual lint trap liner 60 is easily separated from the roll 122 along a perforation 120 , in a manner similar to separating a toilet tissue from a toilet tissue roll (not shown) or a paper towel from a paper towel roll (not shown). The perforations 120 may include any combination of short and long scores 124 or slits separated by short and long portions of lint trap liner 60 material. Scores 124 or slits are intended to include indentations in the lint trap liner 60 material which do not penetrate completely therethrough.
[0059] Each liner 60 comprises a flexible, tenuous meshed membrane 62 adapted for releasable attachment to a lint trap 30 . The membrane 62 has a lint contacting surface 69 opposing a lower surface 67 and is otherwise defined as being substantially identical to the lint trap liner 60 as described above according to the preferred embodiment of the present invention. It is envisioned, however, that this embodiment may also comprise membranes 62 each having a plurality of integral concave protrusions 140 extending outwardly from a continuous peripheral edge thereof, as described above in greater detail.
[0060] In order to facilitate releasable attachment of an individual lint trap liner 60 to the lint trap 30 , an attachment means 70 is provided. For purposes of describing this embodiment, the attachment means 70 comprises a thin film of adhesive 130 bonded to the lower surface 67 of membrane 62 , as described above according to the preferred embodiment, but may comprise alternative attachment means 70 as also described in detail above. The attachment means 70 is adapted to facilitate releasable attachment of each individual membrane 62 to the lint trap 30 .
[0061] Alternative storage and dispensing configurations are contemplated. The liner 60 is further envisioned to be commercially available in the form of pre-measured sheets of uniform or non-uniform dimensions adapted to be stacked upon one another in a desired successional arrangement and dispensed from a suitable dispensing apparatus, such as a box or carton.
[0062] The use of the present invention allows for lint 40 , having accumulated on the meshed media which is attached superjacent to a lint trap 30 , to be peelably removed unitarily from lint trap 30 in a quick, easy, and efficient manner. The lint-accumulation and adherence feature of the present invention also prevents lint 40 or lint particles from scattering into the surrounding environment and falling onto the clothes dryer 10 or a clothes load during removal of the lint trap 30 with attached liner 60 .
2. Operation of the Preferred Embodiment
[0063] To use the present invention, user removably attaches the lint trap liner 60 to the lint collecting surface 94 of the screen web 90 of a lint trap 30 in a superjacent manner using the attachment means 70 . User next inserts the lint trap 30 with attached lint trap liner 60 through the exhaust chute 24 of a clothes dryer 10 in a manner such that the lint contacting surface 69 of liner 60 faces downwardly. User then executes a number of automatic clothes drying loads until a quantity of lint 40 has accumulated atop the lint contacting surface 69 of liner 60 requiring the lint trap 30 with attached liner 60 to be removed for cleaning. User then peelably removes lint-laden liner 60 from lint trap 30 and properly disposes of liner 60 . The lint trap liner 60 is adapted to peel unitarily from the lint trap 30 .
[0064] The use of the present invention allows lint to be peelably removed unitarily from a conventional lint trap in a manner which is quick, easy, and efficient.
[0065] Therefore, the foregoing description is included to illustrate the operation of the preferred embodiment and is not meant to limit the scope of the invention. As one can envision, an individual skilled in the relevant art, in conjunction with the present teachings, would be capable of incorporating many minor modifications that are anticipated within this disclosure. The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments 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 and their equivalents. Therefore, the scope of the invention is to be broadly limited only by the following Claims.
|
A disposable filter media removably attachable to a conventional lint trap utilized in automatic clothes dryers is provided. The disposable filter media is in the form of a flexible, lightweight meshed liner adapted for snug, releasable attachment atop the lint collecting surface of a lint trap. The liner functions to provide optimum lint capturing efficiency without an inordinate drop in the air volume in a clothes dryer and is easily removed and disposed of after use.
| 3
|
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of application Ser. No. 519,565, filed Aug. 2, 1983 U.S. Pat. No. 4,498,325 in the name of Chester F. Jacobson, which in turn is a continuation-in-part of application Ser. No. 419,202, filed Sept. 17, 1982, U.S. Pat. No. 4,492,024 in the name of Chester F. Jacobson.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to wet shaving implements and is directed more particularly to a blade assembly which, as a whole, is movable on a handle assembly during a shaving operation, and having individual blade assembly components which are independently movable during the shaving operation.
2. Description of the Prior Art
It is known in the art to provide a razor blade assembly which may be connected to, and used in conjunction with, a razor handle to facilitate shaving operations. U.S. Pat. No. 3,724,070, issued April 3, 1973, in the name of Francis W. Dorion, Jr. shows a blade assembly in which blade means are held between blade assembly surfaces adapted to engage the surface being shaved in front of and behind, respectively, cutting edge portions of the blade means. Such surfaces are generally referred to as "guard" and "cap".
It is further known that shaving efficiency of such a safety razor assembly may be improved if the blade assembly is adapted to pivot on the razor handle during a shaving operation, permitting the blade assembly to more closely follow the contours of a surface being shaved. U.S. Pat. No. 3,935,639, issued Feb. 3, 1976, in the name of John C. Terry, et al, and U.S. Pat. No. 3,938,247, issued Feb. 17, 1976, in the name of Nelson C. Carbonell, et al, are illustrative of razor handles adapted to accept the blade assembly of the '070 patent in such manner as to permit pivotal movement of the blade assembly during a shaving operation. U.S. Pat. No. 3,950,849, issued April 20, 1976, in the name of Roger L. Perry, illustrates a modified blade assembly adapted for pivotal movement. U.S. Pat. No. 4,026,016, issued May 31, 1977, in the name of Warren I. Nissen, and U.S. Pat. No. 4,083,104, issued April 11, 1978, in the name of Warren I. Nissen, illustrate, respectively, a blade assembly and razor handle comprising a shaving system in which the blade assembly pivots on the handle during shaving. The shaving system shown in the '016 and '104 patents has become well known world-wide.
Another means by which increased shaving efficiency may be obtained is that of retaining the blade assembly, as a whole, stationary but permitting movement of individual components thereof in response to forces encountered during shaving. In U.S. Pat. No. 4,168,571, issued Sept. 25, 1979, in the name of John F. Francis, there is shown a blade assembly in which the guard, cap and blade means are each movable independently of each other in dynamic fashion. U.S. Pat. No. 4,270,268, issued June 2, 1981, in the name of Chester F. Jacobson, shows a blade assembly in which the guard and blade means are independently movable.
In U.S. patent application Ser. No. 419,202, filed Sept. 17, 1982, in the name of Chester F. Jacobson, there is disclosed a safety razor blade assembly adapted for pivotal movement, as a whole, on a razor handle during a shaving operation, and further having blade means movable within the blade assembly in response to forces encountered during a shaving operation.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an improved safety razor blade assembly of the type disclosed in the above referred to '202 application.
With the above and other objects in view, as will hereinafter appear, a feature of the present invention is the provision of a safety razor blade assembly comprising blade means having cutting edge means disposed between skin engaging elements adapted in operation to engage a surface being shaved ahead of and behind, respectively, the cutting edge means, the blade means being movable relative to the elements in response to forces encountered during a shaving operaton, the blade assembly having pivot mounting means thereon for pivotal attachment to a razor handle assembly, whereby the blade assembly, as a whole, is pivotally movable on said handle assembly in response to forces encountered during the shaving operation.
The above and other features of the invention, including various novel details of construction and combinations of parts, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular device embodying the invention is shown by way of illustration only and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.
DESCRIPTION OF THE DRAWINGS
Reference is made to the accompanying drawings in which is shown an illustrative embodiment of the invention from which its novel features and advantages will be apparent.
In the drawings:
FIG. 1 is a top plan view of a housing portion of one form of blade assembly illustrative of an embodiment of the invention;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a sectional view taken along line III--III of FIG. 2;
FIG. 4 is a sectional view taken along line IV--IV of FIG. 1;
FIG. 5 is a top plan view of one form of blade assembly illustrative of an embodiment of the invention;
FIG. 6 is a front elevational view thereof; and
FIG. 7 is a sectional view of the blade assembly, taken along line VII--VII of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, it will be seen that the illustrative razor blade assembly includes a molded plastic body member 2 having first and second end portions 4, 6 interconnected by front and back portions 8, 10. Frame portions 12 extend width-wise of the body member, interconnecting the front and back portions 8, 10.
The back portion 10 of the body member 2 has an upper portion 14 which engages skin being shaved behind the cutting means of the assembly, thereby fulfilling the functions and occupying the position of the "cap" portion of conventional razor blade assemblies. Such portion 14 shall, for that reason, be referred to hereinafter as the "cap portion".
Each of the end portions 4, 6 is provided with opposed slots 16 disposed transversely to the frame portions 12. One of the frame portions 12 near the first end portion 4 is provided with a spring finger 18 molded integrally therewith and extending therefrom generally parallel to the front and back portions 8, 10. The finger 18 is provided with an end portion 20 having an upper surface 22. In like manner, another of the frame portions 12 near the second end portion 6 is provided with an integrally molded spring finger 18' of similar configuration, with end portions 20' having upper surfaces 22'. The fingers 18, 18' extend in opposite directions, the finger 18 extending toward the first end portion 4 of the body member 2 and the finger 18' extending toward the second end portion 6 of the body member. The fingers 18 and 18' are aligned with each other and with a pair of the slots 16.
The first end portion 4 is provided with integrally molded spring fingers 17 extending therefrom inwardly and upwardly of the body member, as viewed in FIGS. 1 and 2. Each of the fingers 17 is provided with an end portion 19 having an upper surface 21 and a rearward surface 23. In like manner, the second end portion 6 is provided with spring fingers 17' of similar configuration, with end portions 19' having upper surfaces 21' and rearward surfaces 23'. The fingers 17, 17' extend in generally opposite directions, the fingers 17 extending from the first end portion 4 generally toward the second end portion 6, and the fingers 17' extending from the second end portion 6 generally toward the first end portion 4. The fingers 17, 17' are each aligned with a pair of the slots 16.
The assembly includes a guard portion 24 having a slide member 26 at either end thereof. The slide members 26 are received in a pair of opposed slots 16 nearest the front wall portion 8. The bottom of the guard portion rests upon the surfaces 22, 22' of the spring fingers 18, 18'. The lower edges of the slide members 26 rest above the bottoms of their slots 16, allowing the guard portion 24 to be moved further into the slots, against the bias of the spring fingers 18, 18' therebeneath. The spring fingers supporting the guard portion comprise a set of spring fingers, the object of which is to resiliently support the guard portion. In a shaving operation, the guard portion travels over the surface being shaved ahead of the cutting means.
The assembly further includes blade means 28 comprising a blade base portion 30, a cutting edge portion 32 extending from the base portion at an obtuse angle thereto, and slide portions at either end of the base portion. The slide portions which may be merely extensions of the blade base portions 30, are received in a pair of the opposed slots 16. An underside 34 of the blade cutting edge portion 32 is engaged by the surfaces 21, 21' of a pair of the spring fingers 17, 17'. Simultaneously, a surface of the blade base portion 30 is engaged by the rearward surfaces 23, 23' of the finger end portions 19 to urge the blade base portions rearwardly in their slots 16, as shown in FIG. 7. Lower edges of the slide portions are spaced from the bottoms of their slots to permit movement of the blades further into the slots 16 against the bias of the spring fingers 17, 17' on which the blade base portion rests. The spring fingers supporting the blade base portion 30 comprise another set of spring fingers, the object of which is to resiliently support the blade means thereon and urge the blade means into a secure position within the slots 16.
In the embodiment illustrated, the blade means include a second blade 28' having a base portion 30', a cutting edge portion 32' extending at an obtuse angle to the base portion 30', and slide portions, all anchored similarly to the above-described first blade means. The slide portions of the second blade are received in a third pair of the opposed slots 16 nearest the cap portion 14 with the cutter portion 34' resting upon spring finger surfaces 21, 21', and with rearward finger surfaces 23, 23' bearing against the second blade base portions 30'. The spring fingers supporting the second blade comprise still another set of spring fingers, which resiliently support the second blade and urge the second blade into a secure position in the slots 16. In a shaving operation, the second blade travels over the surface being shaved behind the first blade.
The guard portion 24, first and second blades 28, 28' are clamped in place by spring clamps 40, which are received in slots 42 in the end portions 4, 6. The clamps 40 engage the guard portion 24 and blades 28, 28' forcing them into the slots 16 to a point where a slight stress is placed on the spring fingers.
On the underside of the body member 2 and the frame portions 12, are disposed two extensions 44, 46 having at their free ends, respectively, inwardly extending opposed rails 48, 50, each rail having respective arcuate upper surfaces 52, 54. The extensions comprise a pivot mounting means by which the blade assembly may be removably and pivotally attached to a razor handle. Referring to FIGS. 2 and 6, it will be seen that the blade assembly body member underside is additionally provided with cam means 56 adapted to receive a cam follower operative to urge the blade assembly to a given position.
Referring again to FIGS. 2 and 6, it will be seen that the blade assembly rails 48, 50, in conjunction with undersurfaces 94, 96 of the body member 2, and arcuate struts 95, 97, define arcuate slots 98, 100 adapted to receive razor handle shell bearings (not shown). The shell bearings comprise a pivot mounting means adapted to cooperate with the above described blade assembly pivot mounting means to facilitate pivotal connection of the blade assembly to the razor handle assembly.
In the handle there is disposed a coil spring and a plunger member the spring biasing the plunger in the direction of the free end of the plunger member. When the blade assembly is connected to the handle assembly, the free end of the plunger member is urged by the spring into engagement with the blade assembly cam means 56. During pivoting operation of the blade assembly, the plunger end bears against the cam means 56, to urge the blade assembly to a given position.
During a shaving operation, the guard portion 24 and the blades 28, 28' move independently of each other against the bias of the spring fingers. At the same time, the blade-supporting spring fingers keep the base portions of the blades in substantially their assigned planes by urging the blade bases rearwardly. Simultaneously, the blade assembly, as a whole, pivots on the handle, following the contours of the surface being shaved.
It is to be understood that the present invention is by no means limited to the particular construction herein disclosed and/or shown in the drawings, but also comprises any modifications or equivalents within the scope of the disclosure. For example, it is preferable under certain conditions that the guard portion be immovable. An alternative embodiment includes a guard portion fixed immovably to the blade assembly body member, but in all other respects structured and operated in accordance with the above description. As a further example, the blade means may include a single blade, rather than the two blade arrangement described, the single blade being used in conjunction with either a movable or stationary guard portion.
|
A razor blade assembly comprising a blade disposed between skin engaging elements adapted in operation to engage a surface being shaved ahead and behind, respectively, of the blade, the blade being movable relative to the elements in response to forces encountered during a shaving operation, the blade assembly having pivot mountings thereon for pivotal attachment to a razor handle, whereby the blade assembly, as a whole, may be pivotally movable on a handle in response to forces encountered during the shaving operation.
| 1
|
This is a continuation of application Ser. No. 08/681,719; filed Jul. 29, 1996, now abandoned, which is a continuation of application Ser. No. 08/448,203; filed May 23, 1995, that is now U.S. Pat. No. 5,569,895, which is a CIP of Ser. No. 08/068,323, May 27, 1993 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to computing systems in general and in particular to sub-assemblies for use in said computing systems.
2. Prior Art
Display sub-assemblies for use as computer I/O devices are well-known in the prior art. The prior art display sub-assemblies usually include a support stand on which the display is mounted. The display could be a cathode ray tube (CRT) or other types of displays. Cables for transmitting power signals and/or data signals interconnect the display to the control unit of the computing assembly. Examples of prior art sub-assemblies are set forth in U.S. Pat. Nos. 4,304,385, 4,738,422, 4,880,191 and 5,024,415. The patents provide tilt, swivel and vertical motion to the displays which they support. The respective motions are necessary so that viewers can adjust the monitor to a position with which they are comfortable.
Even though the prior art devices work well for the intended purpose, they do not provide rotational motion. The need for rotational motion is particularly needed in certain environments, such as point of sale, where it is often required for the display subsystem to be mounted on different sides of the point of sale terminal or be rotated for the customer to view the screen. Even in a regular workstation or other computing environment, the rotational feature gives a user more option to adjust the monitor. The rotational feature tends to improve productivity in that the monitor has a wide range of adjustment and the user can find a position most comfortable. In addition, it may be possible to have more than one user using a single monitor.
SUMMARY OF THE INVENTION
It is therefore a main object of the present invention to provide a more efficient display subassembly than has heretofore been possible.
It is a specific object of the present invention to provide a support mechanism which rotates, swivels and tilts the display device.
It is still another specific object to provide rotation, swivel and tilt motion without tangling or otherwise damaging the cables which interconnect the I/O device to the control unit.
It is yet another object to provide a mounting structure which conceals the cables from origin to destination and therefore provides a more aesthetically pleasing terminal.
These and other objects are provided by a mounting assembly having a unified arm with a vertical section and a cantilever section. A first mechanism which provides swivel and rotational motions couple the vertical section to a base. A second mechanism which provides swivel rotation and tilt motions couple a support means for the I/O device to the cantilever section. The mechanisms enable the mounting assembly to rotate more than 360°. A conduit in the mounting assembly provides routing and conceals the power and signal cables.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a pictorial exploded view of the arm assembly according to the teachings of the present invention.
FIG. 2 shows an assembled pictorial view of the arm assembly according to the teachings of the present invention.
FIG. 3 shows an exploded view of the I/O subassembly of the monitor and arm assembly.
FIG. 4 shows the I/O subassembly rotated clockwise.
FIG. 5 shows the I/O subassembly rotated counter-clockwise.
FIG. 6 shows a rear view of the I/O subassembly and rear cover.
FIG. 7 shows a cross-sectional view of the arm assembly.
FIG. 8 shows the display sub-assembly mounted on a point of sale system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The same numerals are used to identify common elements in FIGS. 1-6 of the drawing. In FIG. 7, alphabetical characters are used to identify common components previously identified by numerical characters.
FIG. 1 shows an exploded view of the support arm assembly according to the teachings of the present invention. The support arm assembly includes a metallic cast base 10 with upstanding integral hollow post 12, also called support number 11 a large sleeve thrust bearing 11, device support arm 14, device support arm cover 22, tilt swivel base 16, tilt swivel retainer 18 and collar member 24.
Still referring to FIG. 1, the metallic cast base 10 is provided with a plurality of holes 10' in which fastening members 10" are used to fasten the support assembly to a flat surface. The large sleeve thrust bearing 12 is a cylindrical bearing with molded-in lubricant. The lower edge 12' of the cylindrical bearing is fitted with a plurality of slots 12'" positioned around the periphery. The slots form a plurality of fingers 12"' which extend outwardly when the bearing is press fitted over integral hollow post 11. The extended fingers co-act with the vertical section 14A (FIG. 2) of support arm 14 to hold it onto the bearing. To assemble the large sleeve thrust bearing 12, it is snapped over the top of the integral hollow post or support member 11 positioned on the cast base. The bearing supports the support arm 14 and acts as one of the pivots for the rotation of the arm. The bearing provides both thrust and radial functions. The bearing also provides the rotational and detenting limiting functions details which will be given subsequently.
The support arm 14 has a hollow vertical section 14A (FIG. 2) and a cantilever section 14B offset from the vertical section 14A. The cantilever sections 14B is non-articulate (i.e. has no joint in it.) The arm is molded from reinforced polycarbonate and supports any device such as a monitor in a cantilever fashion. The arm pivots 90° from center in either direction and is detented every 15°. The direction of pivot is determined by the left, or right location of the display monitor on the surface to which the base is attached. The rotation is always towards the outside of the surface on which the base is mounted. The rotational limit and detenting function is an integral part of the bearing at the bearing/arm interface. The cantilever section 14b of the support arm 14 is provided with an opening 14B' in which a collar 14b" and a stop 14B"' is machined. As will be explained subsequently, when the structure is assembled, the fingers 18' of tilt swivel retainer 18 rides on the undersurface of the collar 14b" to provide rotary motion to tilt swivel base 16 and the stop member 14b'" coacts with stop member 18" on one of the fingers 18' to limit the extent to which the tilt swivel base and tilt swivel retainer can rotate clockwise or counter clockwise. The free end of each of the fingers 18' is hook-shaped and coact with the undersurfaces of collar 14b" to prevent the tilt swivel retainer 18 from escaping after assembly (shown in FIG. 2).
Still referring to FIG. 1, the tilt swivel base 16 is the structure which supports the monitor 26 (FIG. 3) or other devices which the structure supports. Preferably, the tilt swivel base 16 is molded with a spherical opening 16' and upstanding side walls 16" and 16'", respectively. A ledge 17 surround the periphery of opening 16 and provides the ledge surface which cam with the undersurface of tilt swivel retainer 18 to provide tilt motion. The flat surfaces 18"' are provided on the tilt swivel retainer 18. The flat surfaces provide spacings between upstanding side walls 16" and 16"', respectively and allow the ledge surface to cam with the undersurface of tilt swivel retainer 18 in a direction substantially perpendicular to the tilt direction to provide swivel motion. A user has to adjust the tilt swivel base 16 in a desired direction in order to get the different motions. Hooks or contact members 19 are positioned on the top surface of tilt swivel base 16 and hold the monitor firmly onto the base. Of course, it is within the skill of one skilled in the art to provide other attachment mechanisms without departing from the spirit or scope of the present invention. It should be noted that this tilt and swivel base 16 coacting with swivel retainer 18, collar 146" and stop 14b'" provides tilt, swivel and rotation motion to the device mounted on it.
The tilt swivel retainer 18 captures the tilt/swivel base 16 by snapping into the previously-described openings 14B' and 16'. Both the tilt limits and the rotational limits of the tilt swivel base 16 are determined by this retainer and the length of the spherical opening 16'. The tilt limit is the length of the spherical opening 16' through which the tilt/swivel base 16 passes. The rotational limit is an integral part of the retainer at the retainer/arm interface and is provided by the stop member 18" coacting with stop 14b'". The opening in the arm, both the cantilever section 14B and the vertical section, allows cables and other wires to the threaded to the attached monitor. The arm cover 22 fits into the opening 15 in the support arm.
FIG. 2 shows the support arm 14 in its assembled form. A separate cable cover assembly 28 is fitted into an opening in the tilt swivel base 16. As will be described subsequently, the hook members 29, on the cover assembly 28, hooks into holes on the backside of the monitor. Of course, it is within the skill of the art to provide other types of attachment mechanisms without departing from the scope or spirit of the present invention. This cover assembly 28 conceals the power and signal card (to be shown subsequently) from the point of exit from the display along the underside to a point where the cables enter into tilt swivel base 16. It should be noted that flat surface 18"' does not contact sidewall 16". Instead, there is a spacing between both. Similarly, the relationship between flat surface 18"' and sidewall 16'", on the opposite side, are identical (i.e. spacing between both). Consequently, the spacing allows the tilt swivel base 16 to move, relative to the tilt swivel retainer 18, in a direction substantially perpendicular to the tilt direction to provide the swivel.
Turning now to FIG. 3, the route for interconnecting the monitor to the system unit by cables are shown. The monitor 26 is attached to the tilt swivel base 16 via the hooks on this base and slots (not shown) in the bottom of the display monitor housing 26. As stated previously, other types of devices can be used for attaching without departing from the spirit of the present invention. The total monitor rotation is greater than 400°, and is a combination of the tilt/full rotation and the monitor arm pivot capability. This rotation is achieved, regardless of whether the display monitor is mounted on the left or right side of either a system unit or a cash drawer of a point of sale system. The monitor could be mounted on the system unit, in an integral system (I/O on top of the system unit). Or the monitor can be mounted on the cash drawer in a distributed (the I/O on top of the cash drawer with the system unit located remotely) system.
Referring now to FIG. 6, the power cable 30 and signal cable 32 are shown threaded through the opening provided in the arm assembly and connecting at one end to display unit 26. The power and signal cables are concealed within all of these component parts. The cables are routed from the monitor, through the hole 18 in the tilt, swivel retainer 16 back towards the pivot bearing, down through the bearing and hollow post portion of the cast base, to the control units where it is attached to the respective ports of the unit. The separate cable cover is then attached to the rear of the display monitor. This conceals the cables from their origin to their termination. This concealment provides for an unencumbered, neat overall appearance, absolute minimum cable exposure to external elements/damage, while providing a more reliable system operation because all cables and cable connections are now concealed within the system
FIGS. 4 and 5 show various clockwise and counter clockwise positions in which the monitor can be rotated to provide maximum adjustment to a user. With respect to FIG. 4, the rotation is clockwise as shown by arrows 36, 38 and 40, respectively. Similarly, the rotation in FIG. 5 is in a counter clockwise direction shown by arrows 42, 44 and 46, respectively.
FIG. 7 shows a cross-sectional view of the support assembly. In this figure, alphabetical characters are used to identify the various component parts. The rigid cast metal base A is attached to rigid support surface by screws (not shown). The rigid cast metal base A has a cylindrical hollow tube section or support member AA extending upwardly from the base section. The cylindrical plastic bearing C is pressed onto the outside of hollow tube AA and is held into place with snap fingers CC which also prevent plastic bearing C from rotating on the hollow tube AA. The plastic bearing C also has molded in stop feature D which coact with B' and B' on the arm B to limit rotation of arm B to 180° (+/- 90° from center position). The cylindrical part of plastic arm B is assembled around fixed cylindrical bearing C. The lower outer rim of the bearing C has flared tabs CCC which provide retention and rotation indexing for arm B. The plastic plug E snaps in and out of arm B to ease cable routing and installation within the arm assembly.
The arm B has a spherical surface in which the spherical surface FF of device mount F rests. The spherical surfaces allow the device mount to tilt relative to the arm B. The device mount also rotates relative to arm B.
Still referring to FIG. 7, the device mount F is provided with an oval slot FFF which aligns with hole or opening B' fabricated in arm B. The device mount F is held into arm B by a first section of retainer G (also called a second section) which has a central opening with fingers G' extending downwardly into opening B' of arm B. A circular ridge B" and a traverse ridge B"' which extends upwardly from the circular ridge B" are machined into the inside surface of the opening B'. The fingers G' ride on circular ridge B'" and the traverse ridge B'" stops the circular motion of the retainer G and the trapped device mount F. The retainer G passes through monitor mount F and arm B and is held in place with retention snap fingers GG. The retainer G retains mount F to arm B and is hollow to allow cables to pass through. The retainer G rotates with device mount F and has modified snap finger H which rotates in a groove in arm B. The modified finger H and the upstanding traverse ridge B'" limits rotation of mount F and retainer G. Stated another way, modified snap finger H is blocked by traverse ridge B"' and, as such, the rotation of retainer G and device mount F is limited to 330° from center in either direction.
Still referring to FIG. 7, the device mount F has oval slot FFF which stops at retainer G and limits tilt to +15°, -5° from vertical. The mount F has hooks and latches J which mate with cooling slots in the CRT monitor and rigidly fix CRT monitor (or any other viewing device) to mount F. The cable path K shows routing of multiple cables through the support assembly. Cables in this path K are hidden from normal view and are protected from damage by controlling the articulation or motion of the structure at the respective articulation points of the support system.
The unique feature of the described mounting method and mounting assembly provides the maximum amount of device monitor usefulness, i.e., pivot, rotation, tilt, swivel and location positioning while concealing and protecting the cables and connections. When used in a point of sale system used in the checkout counter of most business establishments, the described mounting assembly and method provides for the display monitor to be mounted either on the right or left side of the point of sale system unit and provide all enunciated capabilities and advantages at either location.
FIG. 8 shows a pictorial view of the display sub-assembly mounted on a point of sale (POS) system. The display sub-assembly includes display 26 and display stand or support arm 14. As stated previously, the display stand is mounted on the POS terminal and supports the display which could be a cathode ray tube (CRT) or similar device. The display functions as an I/O device for the POS terminal. The POS terminal includes a printer 50, keyboard 52, control unit or computer 54 and cash drawer 56. Each of the named devices is used to perform its conventional function. Support structure 58 is mounted on the computer 54 and devices 52 and 50 are mounted on the support structure 58. FIG. 8 shows the units in a clustered configuration. An alternate configuration would be a distributed one in which the units are separated and the display sub-system is mounted on the computer 54 or cash drawer 56.
While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those of skill in the art that modifications and variations in form and detail may be made therein without departing from the spirit and scope of the invention.
What we desire to protect by Letters Patent is.
|
A computer Input/Output (I/O) assembly including a stand for supporting an I/O device, such as a display or the like. The stand includes a main support member and an auxiliary support member offset from the main support member. A mechanism providing swivel and rotational motions coupled the main support member to a base and another mechanism providing swivel, rotation, and tilt motions couples the auxiliary support member to the I/O device. The total rotational motion provided by the mechanisms is greater than 360°.
| 8
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of co-pending U.S. patent application Ser. No. 10/319,792, filed Dec. 13, 2002. The aforementioned related patent application is herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to wellbore completion. More particularly, the invention relates to methods for drilling with casing and landing a casing mandrel in a subsea wellhead.
[0004] 2. Description of the Related Art
[0005] In a conventional completion operation, a wellbore is formed in several phases. In a first phase, the wellbore is formed using a drill bit that is urged downwardly at a lower end of a drill string while simultaneously circulating drilling mud into the wellbore. The drilling mud is circulated downhole to carry rock chips to the surface and to cool and clean the bit. After drilling a predetermined depth, the drill string and bit are removed.
[0006] In a next phase, the wellbore is lined with a string of steel pipe called casing. The casing is inserted into the newly formed wellbore to provide support to the wellbore and facilitate the isolation of certain areas of the wellbore adjacent to hydrocarbon bearing formations. Generally, a casing shoe is attached to the bottom of the casing string to facilitate the passage of cement that will fill an annular area defined between the casing and the wellbore.
[0007] A recent trend in well completion has been the advent of one-pass drilling, otherwise known as “drilling with casing”. It has been discovered that drilling with casing is a time effective method of forming a wellbore where a drill bit is attached to the same string of tubulars that will line the wellbore. In other words, rather than run a drill bit on smaller diameter drill string, the bit or drillshoe is run at the end of larger diameter tubing or casing that will remain in the wellbore and be cemented therein. The advantages of drilling with casing are obvious. Because the same string of tubulars transports the bit as it lines the wellbore, no separate trip into the wellbore is necessary between the forming of the wellbore and the lining of the wellbore.
[0008] Drilling with casing is especially useful in certain situations where an operator wants to drill and line a wellbore as quickly as possible to minimize the time the wellbore remains unlined and subject to collapse or the effects of pressure anomalies. For example, when forming a subsea wellbore, the initial length of wellbore extending downwards from the ocean floor is subject to cave in or collapse due to soft formations at the ocean floor. Additionally, sections of a wellbore that intersect areas of high pressure can lead to damage of the wellbore between the time the wellbore is formed and when it is lined. An area of exceptionally low pressure will drain expensive drilling fluid from the wellbore between the time it is intersected and when the wellbore is lined. In each of these instances, the problems can be eliminated or their effects reduced by drilling with casing.
[0009] While one-pass drilling offers obvious advantages over a conventional completion operation, there are some additional problems using the technology to form a subsea well because of the sealing requirements necessary in a high-pressure environment at the ocean floor. Generally, the subsea wellhead comprises a casing hanger with a locking mechanism and a landing shoulder while the string of casing includes a sealing assembly and a casing mandrel for landing in the wellhead. Typically, the subsea wellbore is drilled to a depth greater than the length of the casing, thereby allowing the casing string and the casing mandrel to easily seat in the wellhead as the string of casing is inserted into the subsea wellbore. However, in a one-pass completion operation, the casing is rotated as the wellbore is formed and landing the casing mandrel in the wellhead would necessarily involve rotating the sealing surfaces of the casing mandrel and the sealing surfaces of the wellhead. Additionally, in one-pass completion an obstruction may be encountered while drilling with casing, whereby the casing hanger may not be able to move axially downward far enough to land in the subsea wellhead, resulting in the inability to seal the subsea wellhead.
[0010] A need therefore exists for a method of drilling with casing that facilitates the landing of a casing hanger in a subsea wellhead. There is a further need for a method that prevents damage to the seal assembly as the casing mandrel seats in the casing hanger. There is yet a further need for a method for landing a casing hanger in a subsea wellhead after an obstruction is encountered during the drilling operation.
SUMMARY OF THE INVENTION
[0011] The present invention generally relates to methods for drilling a subsea wellbore and landing a casing mandrel in a subsea wellhead. In one aspect, a method of drilling a subsea wellbore with casing is provided. The method includes placing a string of casing with a drill bit at the lower end thereof in a riser system and urging the string of casing axially downward. The method further includes reducing the axial length of the string of casing to land a wellbore component in a subsea wellhead. In this manner, the wellbore is formed and lined with the string of casing in a single run.
[0012] In another aspect, a method of forming and lining a subsea wellbore is provided. The method includes disposing a run-in string with a casing string at the lower end thereof in a riser system, the casing string having a casing mandrel disposed at an upper end thereof and a drill bit disposed at a lower end thereof. The method further includes rotating the casing string while urging the casing string axially downward to a predetermined depth, whereby the casing mandrel is at a predetermined height above a casing hanger. Additionally, the method includes reducing the length of the casing string thereby seating the casing mandrel in the casing hanger.
[0013] In yet another aspect, a method of landing a casing mandrel in a casing hanger disposed in a subsea wellhead is provided. The method includes placing a casing string with the casing mandrel disposed at the upper end thereof into a riser system and drilling the casing string into the subsea welihead to form a wellbore. The method further includes positioning the casing mandrel at a predetermined height above the casing hanger and reducing the axial length of the casing string to seat the casing mandrel in the casing hanger.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of 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.
[0015] FIG. 1 is a partial section view and illustrates the formation of a subsea wellbore with a casing string having a drill bit disposed at a lower end thereof.
[0016] FIG. 2 is a cross-sectional view illustrating the string of casing prior to setting a casing mandrel into a casing hanger of the subsea wellhead.
[0017] FIG. 3 is an enlarged cross-sectional view illustrating a collapsible apparatus of the casing string in a first position.
[0018] FIG. 4 is a cross-sectional view illustrating the casing assembly after the casing mandrel is seated in the casing hanger.
[0019] FIG. 5A is an enlarged cross-sectional view illustrating the collapsible apparatus in a second position after the casing mandrel is set into the casing hanger.
[0020] FIG. 5B is a cross-sectional view taken along line 5 B-- 5 B of FIG. 5A illustrating a torque key engaged between the string of casing and a tubular member in the collapsible apparatus.
[0021] FIG. 6A is a cross-sectional view of an alternative embodiment illustrating pre-milled windows in the casing assembly.
[0022] FIG. 6B is a cross-sectional view illustrating the casing assembly after alignment of the pre-milled windows.
[0023] FIG. 6C is a cross-sectional view illustrating a diverter disposed adjacent the pre-milled windows.
[0024] FIG. 6D is a cross-sectional view illustrating a drilling assembly diverted through the pre-milled windows.
[0025] FIG. 7A is a cross-sectional view of an alternative embodiment illustrating a hollow diverter in the casing assembly.
[0026] FIG. 7B is a cross-sectional view illustrating a lateral bore drilling operation.
[0027] FIGS. 8A is a cross-sectional view illustrating the casing assembly with a casing drilling shoe.
[0028] FIG. 8B is a cross-sectional view illustrating the casing assembly with a casing drilling shoe.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] The present invention generally relates to drilling a subsea wellbore using a casing string. FIG. 1 illustrates a drilling operation of a subsea wellbore with a casing assembly 170 in accordance with the present invention. Typically, most offshore drilling in deep water is conducted from a floating vessel 105 that supports the drill rig and derrick and associated drilling equipment. A riser pipe 110 is normally used to interconnect the floating vessel 105 and a subsea wellhead 115 . A run-in string 120 extends from the floating vessel 105 through the riser pipe 110 . The riser pipe 110 serves to guide the run-in string 120 into the subsea wellhead 115 and to conduct returning drilling fluid back to the floating vessel 105 during the drilling operation through an annulus 125 created between the riser pipe 110 and run-in string 120 . The riser pipe 110 is illustrated larger than a standard riser pipe for clarity.
[0030] A running tool 130 is disposed at the lower end of the run-in string 120 . Generally, the running tool 130 is used in the placement or setting of downhole equipment and may be retrieved after the operation or setting process. The running tool 130 in this invention is used to connect the run-in string 120 to the casing assembly 170 and subsequently release the casing assembly 170 after the wellbore 100 is formed.
[0031] The casing assembly 170 is constructed of a casing mandrel 135 , a string of casing 150 and a collapsible apparatus 160 . The casing mandrel 135 is disposed at the upper end of the string of casing 150 . The casing mandrel 135 is constructed and arranged to seal and secure the string of casing 150 in the subsea wellhead 115 . As shown on FIG. 1 , a collapsible apparatus 160 is disposed at the bottom of the string of casing 150 . However, it should be noted that the collapsible apparatus 160 is not limited to the location illustrated on FIG. 1 , but may be located at any point on the string of casing 150 .
[0032] A drill bit 140 is disposed at the lowest point on the casing assembly 170 to form the wellbore 100 . In the embodiment shown, the drill bit 140 is rotated with the casing assembly 170 . Alternatively, mud motor (not shown) may be used near the end of the string of casing 150 to rotate the bit 140 . In another embodiment, a casing drilling shoe 370 may be employed at the lower end of the casing assembly 170 , as illustrated in FIGS. 8A and 8B . An example of a casing drilling shoe is disclosed in Wardley, U.S. Pat. No. 6,443,247 which is incorporated herein in its entirety. Generally, the casing drilling shoe disclosed in '247 includes an outer drilling section constructed of a relatively hard material such as steel, and an inner section constructed of a readily drillable material such as aluminum. The drilling shoe further includes a device for controllably displacing the outer drilling section to enable the shoe to be drilled through using a standard drill bit and subsequently penetrated by a reduced diameter casing string or liner.
[0033] As illustrated by the embodiment shown in FIG. 1 , the wellbore 100 is formed as the casing assembly 170 is rotated and urged downward. Typically, drilling fluid is pumped through the run-in string 120 and the string of casing 150 to the drill bit 140 . A motor (not shown) rotates the run-in string 120 and the run-in string 120 transmits rotational torque to the casing assembly 170 and the drill bit 140 . At the same time, the run-in string 120 , the running tool 130 , the casing assembly 170 and drill bit 140 are urged downward. In this respect, the run-in string 120 , the running tool 130 and the casing assembly 170 act as one rotationally locked unit to form a predetermined length of wellbore 100 as shown on FIG. 2 .
[0034] FIG. 2 is a cross-sectional view illustrating the casing assembly 170 prior to setting the casing mandrel 135 into a casing hanger 205 . Generally, the wellbore 100 is formed to a predetermined depth and thereafter the rotation of the casing assembly 170 is stopped. Typically, the predetermined depth is a point where a lower surface 215 on the casing mandrel 135 is a predetermined height above an upper portion of the casing hanger 205 in the subsea wellhead 115 as shown in FIG. 2 .
[0035] The casing mandrel 135 is typically constructed and arranged from steel that has a smooth metallic face. However, other types of materials may be employed, so long as the material will permit an effective seal between the casing mandrel 135 and the casing hanger 205 . The casing mandrel 135 may further include one or more seals 220 disposed around an outer portion of the casing mandrel 135 . The one or more seals 220 are later used to create a seal between the casing mandrel 135 and the casing hanger 205 .
[0036] As shown in FIG. 2 , the casing hanger 205 is disposed in the subsea surface. Typically, the casing hanger 205 is located and cemented in the subsea surface prior to drilling the wellbore 100 . The casing hanger 205 is typically constructed from steel. However, other types of materials may be employed so long as the material will permit an effective seal between the casing mandrel 135 and the casing hanger 205 . The casing hanger 205 includes a landing shoulder 210 formed at the lower end of the casing hanger 205 to mate with the lower surface 215 formed on the lower end of the casing mandrel 135 .
[0037] FIG. 3 is an enlarged cross-sectional view illustrating the collapsible apparatus 160 in a first position. Generally, the collapsible apparatus 160 moves between the first position and a second position allowing the overall length of the casing assembly 170 to be reduced. As the casing assembly 170 length is reduced, the casing mandrel 135 may seat in the casing hanger 205 sealing the subsea wellhead 115 without damaging the one or more seals 220 . In another aspect, reducing the axial length of the casing assembly 170 also provides a means for landing the casing mandrel 135 in the casing hanger 205 after an obstruction is encountered during the drilling operation, whereby the casing assembly 170 can no longer urged axially downward to seal off the subsea wellhead 115 .
[0038] As illustrated, the collapsible apparatus 160 includes one or more seals 305 to create a seal between the string of casing 150 and a tubular member 315 . The tubular member 315 is constructed of a predetermined length to allow the casing mandrel 135 to seat properly in the casing hanger 205 .
[0039] The tubular member 315 is secured axially to the string of casing 150 by a locking mechanism 310 . The locking mechanism 310 is illustrated as a shear pin. However, other forms of locking mechanisms may be employed, so long as the locking mechanism will fail at a predetermined force. Generally, the locking mechanism 310 is short piece of metal that is used to retain tubular member 315 and the string of casing 150 in a fixed position until sufficient axial force is applied to cause the locking mechanism to fail. Once the locking mechanism 310 fails, the string of casing 150 may then move axially downward to reduce the length of the casing assembly 170 . Typically, a mechanical or hydraulic axial force is applied to the casing assembly 170 , thereby causing the locking mechanism 310 to fail. Alternatively, a wireline apparatus (not shown) may be run through the casing assembly 170 and employed to provide the axial force required to cause the locking mechanism 310 to fail. In an alternative embodiment, the locking mechanism 310 is constructed and arranged to deactivate upon receipt of a signal 380 from the surface, as illustrated in FIG. 4 . The signal 380 may be axial, torsional or combinations thereof and the signal 380 may be transmitted through wire casing, wireline, hydraulics or any other means well known in the art.
[0040] In addition to securing the tubular member 315 axially to the string of casing 150 , the locking mechanism 310 also provides a means for a mechanical torque connection. In other words, as the string of casing 150 is rotated the torsional force is transmitted to the collapsible apparatus 160 through the locking mechanism 310 . Alternatively, a spline assembly may be employed to transmit the torsional force between the string of casing 150 and the collapsible apparatus 160 . Generally, a spline assembly is a mechanical torque connection between a first and second member. Typically, the first member includes a plurality of keys and the second member includes a plurality of keyways. When rotational torque is applied to the first member, the keys act on the keyways to transmit the torque to the second member. Additionally, the spline assembly may be disengaged by axial movement of one member relative to the other member, thereby permitting rotational freedom of each member.
[0041] FIG. 4 is a cross-sectional view illustrating the casing assembly 170 after the casing mandrel 135 is seated in the casing hanger 205 . A mechanical or hydraulic axial force was applied to the casing assembly 170 causing the locking mechanism 310 to fail and allow the string of casing 150 to move axially downward and slide over the tubular member 315 . It is to be understood, however, that the casing apparatus 160 may be constructed and arranged to permit the string of casing 150 to slide inside the tubular member 315 to obtain the same desired result.
[0042] As illustrated on FIG. 4 , the lower surface 215 has contacted the landing shoulder 210 , thereby seating the casing mandrel 135 in the casing hanger 205 . As further illustrated, the one or more seals 220 on the casing mandrel 135 are in contact with the casing hanger 205 , thereby creating a fluid tight seal between the casing mandrel 135 in the casing hanger 205 during the drilling and cementing operations. In this manner, the length of the casing assembly 170 is reduced allowing the casing mandrel 135 to seat in the casing hanger 205 .
[0043] FIG. 5A is an enlarged cross-sectional view illustrating the collapsible apparatus 160 in the second position after the casing mandrel 135 is seated in the casing hanger 205 . As illustrated, the locking mechanism 310 has released the connection point between the string of casing 150 and the tubular member 315 , thereby allowing the string of casing 150 to slide axially downward toward the bit 140 . The axial downward movement of the string of casing 150 permits an inwardly biased torque key 330 to engage a groove 320 at the lower end of the tubular member 315 . The torque key 330 creates a mechanical torque connection between the string of casing 150 and the collapsible apparatus 160 when the collapsible apparatus 160 is in the second position. Alternatively, a mechanical spline assembly may be used to create a torque connection between the string of casing 150 and the collapsible apparatus 160 .
[0044] In another aspect, the axial movement of the collapsible apparatus 160 from the first position to the second position may be used to activate other downhole components. For example, the axial movement of the collapsible apparatus 160 may displace an outer drilling section of a drilling shoe (not shown) to allow the drilling shoe to be drilled therethrough, as discussed in a previous paragraph relating to Wardley, U.S. Pat. No. 6,443,247. In another example, the axial movement of the collapsible apparatus 160 may urge a sleeve in a float apparatus (not shown) from a first position to a second position to activate the float apparatus.
[0045] FIG. 5B is a cross-sectional view taken along line 5 B- 5 B of FIG. 5A illustrating the torque key 330 engaged between the string of casing 150 and the tubular member 315 . As shown, the torque key 330 has moved radially inward, thereby establishing a mechanical connection between the string of casing 150 and the tubular member 315 .
[0046] In an alternative embodiment, the casing assembly 170 may be drilled down until the lower surface 215 of the casing mandrel 135 is right above the upper portion of the casing hanger 205 . Thereafter, the rotation of the casing assembly 170 is stopped. Next, the run-in string 120 is allowed to slack off causing all or part of the string of casing 150 to be in compression, which reduces the length of the string of casing 150 . Subsequently, the reduction of length in the string of casing 150 allows the casing mandrel 135 to seat into the casing hanger 205 .
[0047] In a further alternative embodiment, a centralizer 385 , as illustrated in FIG. 4 , may be disposed on the string of casing 150 to position the string of casing 150 concentrically in the wellbore 100 . Generally, a centralizer is usually used during cementing operations to provide a constant annular space around the string of casing 150 , rather than having the string of casing 150 laying eccentrically against the wellbore 100 wall. For straight holes, bow spring centralizers are sufficient and commonly employed. For deviated wellbores, where gravitational force pulls the string of casing 150 to the low side of the hole, more robust solid-bladed centralizers are employed.
[0048] FIG. 6A is a cross-sectional view of an alternative embodiment illustrating pre-milled windows 325 , 335 in the casing assembly 170 . In the embodiment shown, the pre-milled window 325 is formed in a lower portion of the string of casing 150 . Pre-milled window 325 is constructed and arranged to align with pre-milled window 335 formed in the tubular member 315 after the collapsible apparatus 160 has moved to the second position. Additionally, a plurality of seals 340 are disposed around the string of casing 150 to create a fluid tight seal between the string of casing 150 and the tubular member 315 .
[0049] FIG. 6B is a cross-sectional view illustrating the casing assembly 170 after alignment of the pre-milled windows 325 , 335 . As shown, the locking mechanism 310 has failed in a manner discussed in a previous paragraph, and the collapsible apparatus 160 has moved to the second position permitting the axial alignment of the pre-milled windows 325 , 335 . Additionally, the inwardly biased torque key 330 has engaged the groove 320 formed at the lower end of the tubular member 315 , thereby rotationally aligning the pre-milled windows 325 , 335 . In this manner, the pre-milled windows 325 , 335 are aligned both axially and rotationally to provide an access window between the inner portion of the casing assembly 170 and the surrounding wellbore 100 .
[0050] FIG. 6C is a cross-sectional view illustrating a diverter 345 disposed adjacent the pre-milled windows 325 , 335 . The diverter 345 is typically disposed and secured in the string of casing 150 by a wireline assembly (not shown) or other means well known in the art. Generally, the diverter 345 is an inclined wedge placed in a wellbore 100 to force a drilling assembly (not shown) to start drilling in a direction away from the wellbore 100 axis. The diverter 345 must have hard steel surfaces so that the drilling assembly will preferentially drill through rock rather than the diverter 345 itself. In the embodiment shown, the diverter 345 is oriented to direct the drilling assembly outward through the pre-milled windows 325 , 335 .
[0051] FIG. 6D is a cross-sectional view illustrating a drilling assembly 350 diverted through the pre-milled windows 325 , 335 . As shown, the diverter 345 has directed the drilling assembly 350 through the pre-milled windows 325 , 335 to form a lateral wellbore.
[0052] FIG. 7A is a cross-sectional view of an alternative embodiment illustrating a hollow diverter 355 in the casing assembly 150 . Prior to forming the wellbore 100 with the string of casing 150 , the hollow diverter 355 is disposed in the string of casing 150 at a predetermined location. The hollow diverter 355 may be oriented in a particular direction if needed, or placed into the string of casing 150 blind, with no regard to the direction. In either case, the hollow diverter 355 functions in a similar manner as discussed in the previous paragraph. However, a unique aspect of the hollow diverter 355 is that it is constructed and arranged with a fluid bypass 360 . The fluid bypass 360 permits drilling fluid that is pumped from the surface of the wellbore 100 to be communicated to the drill bit 140 during the drilling by casing operation. In other words, the installation of the hollow diverter 355 in the string of casing 150 prior to drilling the wellbore 100 will not block fluid communication between the surface of the wellbore 100 and the drill bit 140 during the drilling operation.
[0053] FIG. 7B is a cross-sectional view illustrating a lateral bore drilling operation using the hollow diverter 355 . As shown, the hollow diverter 355 has directed the drilling assembly 350 away from the wellbore 100 axis to form a lateral wellbore.
[0054] In operation, a casing assembly is attached to the end of a run-in string by a running tool and thereafter lowered through a riser system that interconnects a floating vessel and a subsea wellhead. The casing assembly is constructed from a casing mandrel, a string of casing and a collapsible apparatus. After the casing assembly enters the subsea wellhead, the casing assembly is rotated and urged axially downward to form a subsea wellbore.
[0055] Typically, a motor rotates the run-in string and subsequently the run-in string transmits the rotational torque to the casing assembly and a drill disposed at a lower end thereof. At the same time, the run-in string, the running tool, the casing assembly and drill bit are urged axially downward until a lower surface on the casing mandrel of the casing assembly is positioned at a predetermined height above an upper portion of the casing hanger. At this time, the rotation of the casing assembly is stopped. Thereafter, a mechanical or hydraulic axial force is applied to the casing assembly causing a locking mechanism in the collapsible apparatus to fail and allows the string of casing to move axially downward to reduce the overall length of the casing assembly permitting the casing mandrel to seat in the casing hanger. Additionally, the axial downward movement of the string of casing permits an inwardly biased torque key to engage a groove at the lower end of the tubular member to create a mechanical torque connection between the string of casing and the collapsible apparatus. Thereafter, the string of casing is cemented into the wellbore and the entire run-in string is removed from the wellbore.
[0056] While the foregoing is directed to embodiments 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 generally relates to methods for drilling a subsea wellbore and landing a casing mandrel in a subsea wellhead. In one aspect, a method of drilling a subsea wellbore with casing is provided. The method includes placing a string of casing with a drill bit at the lower end thereof in a riser system and urging the string of casing axially downward. The method further includes reducing the axial length of the string of casing to land a wellbore component in a subsea wellhead. In this manner, the wellbore is formed and lined with the string of casing in a single run. In another aspect, a method of forming and lining a subsea wellbore is provided. In yet another aspect, a method of landing a casing mandrel in a casing hanger disposed in a subsea wellhead is provided.
| 4
|
BACKGROUND OF THE INVENTION
This invention relates, in general, to shoe lace retainers, and, in particular, to shoe lace retainers for any type of shoes having laces.
DESCRIPTION OF THE PRIOR ART
In the prior art various types of lace retainers have been proposed. For example, U.S. Pat. No. 4,571,854 to Edens discloses a knot latch device with a plurality of mating hook and loop elements which fasten the device around a knotted shoe lace.
U.S. Pat. No. 4,999,888 to Miller discloses a shoelace retainer which is a flexible, elongated strap having a plurality of loop elements on an opposite surface to secure a knotted shoe lace.
U.S. Pat. No. 5,022,127 to Ang discloses a shoelace locking device with holes through which the laces can be threaded to attach it to a shoe.
U.S. Pat. No. 5,165,190 to Smyth discloses a laces shoe fastener, one part of which attaches to the shoe and the other part is secured to the first part by hook and loop fasteners.
SUMMARY OF THE INVENTION
The present invention is a retainer for knotted shoe laces that surrounds a knotted or tied shoe lace and prevents the lace from coming loose.
It is an object of the present invention to provide a retainer for knotted shoelaces.
It is an object of the present invention to provide a retainer for knotted shoelaces that is easy to apply.
It is an object of the present invention to provide a retainer for knotted shoelaces that can be used with any type of shoes which have laces.
These and other objects and advantages of the present invention will be fully apparent from the following description, when taken in connection with the annexed drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the present invention.
FIG. 2 is a view showing the retainer of the present invention in position around a knotted shoe lace.
FIG. 3 is a view of the retainer of the present invention around a knotted shoe lace before the retainer is applied to the shoelace.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in greater detail, FIG. 1 shows the shoe lace wrap 1 of the present invention. The wrap comprises a body portion 2, which can be made from any type of material such as, but not limited to, canvas or plastic. Also, it should be noted that the body 2 is shown as being rectangular, however, the shape is not critical and other shapes such as circular could be used. In addition, the straps 3, 4 are shown in FIG. 1 as being unitary with the body 2, but they could also be made as separate pieces and made integral with the body 2 such as by sewing or gluing.
Attached to the body 2 are a pair of straps 3, 4 which can be made from the same material as the body 2 or a different material. The straps 3, 4 extend away from the body on opposite sides of the body as shown in FIG. 1. The end of the strap 3 has a hook and loop type fastener 5 attached thereto in any conventional manner. The end of the strap 4 has a hook and loop type fastener 6 attached thereto in any conventional manner. The body 2 has complimentary hook and loop fasteners 8, 9 attached thereto in any conventional manner, which will cooperate with the fasteners 5, 6 to hold the body around the knotted laces 7 as shown in FIG. 2.
In order to attach the lace wrap 1 the wrap is first placed under the area where the knot 10 will be when the laces are tied (see FIG. 3). Then the shoe lace 7 will be tied in the normal manner. Once the shoe lace is tied, the lace wrap 1 is rolled into the shape shown in FIG. 2, and secured by means of the straps 3, 4 and the fasteners 5, 6 on the straps engaging the fasteners 8, 9 on the body 2.
Once the wrap 1 is secured around the laces 7 the knot, it will be less likely that the knot will come untied. Also, since the straps 3, 4 extend in opposite directions around the body 2, it is unlikely that a person might accidentally catch both of the straps 3, 4 on an obstacle and accidentally pull the wrap 1 loose. That is if a person accidentally snags one of the straps 3, 4 on an obstacle as they are walking, the obstacle might pull one of the straps loose, however, since the straps extend in opposite directions, both straps will not be pulled loose. This means that the wrap 1 will remain, at least partially attached to the knotted shoelace and this will prevent the knot from being pulled loose.
Although the Lace Wraps and the method of using the same according to the present invention has been described in the foregoing specification with considerable details, it is to be understood that modifications may be made to the invention which do not exceed the scope of the appended claims and modified forms of the present invention done by others skilled in the art to which the invention pertains will be considered infringements of this invention when those modified forms fall within the claimed scope of this invention.
|
A retainer for knotted shoe laces that surrounds a knotted or tied shoe lace and prevents the lace from coming loose.
| 8
|
FIELD OF THE INVENTION
The disclosure generally relates to wind turbines and, more particularly to ground testing of a yawing system of a wind turbine prior to erection.
BACKGROUND OF THE INVENTION
A wind turbine comprises several components including a tower, a nacelle, a generator, a rotor comprising a hub and rotor blades and so on. Yaw systems are conventionally used in wind power stations to yaw the turbine nacelle to the required angle against the wind. When a wind turbine is erected, the blades, the hub, the tower and the nacelle are transported to the site of erection. The tower is erected, the nacelle is mounted on the tower, the hub is mounted on the nacelle and the rotor blades are attached to the hub by means of at least one crane. When erected on land, normally mobile cranes are used to position, orient and arrange the components relatively to each other so that the components are able to be mounted together. During this erection phase in wind turbine construction, it is also necessary to yaw the nacelle while mounting the rotor and again, post lifting, to allow the crane to track unobstructed to the next site. As in any other physical systems, faults/failures may occur in the system. Specifically, if there are any failures with the yaw system during the erection phase, costly standstills of manpower and equipment will result.
In order to operate and test the yaw and hydraulic systems, specific voltages must be supplied to the nacelle. Unfortunately, yaw failures can only be detected after the nacelle is erected on the tower because the required voltages are not available on the ground.
Wind turbines, yaw controls, and testing systems are well known in the art, including those described in US Patent and Application Nos. 2009/0100918, 2009/0016227, 2008/0266400, 2008/0307647, 2009/0004009, 2009/0039651, 2009/0129931, each of which is incorporated herein by reference.
SUMMARY OF THE INVENTION
Systems and methods for ground testing yaw systems of wind turbines are provided. In this regard, an exemplary embodiment of system for ground testing yaw systems of wind turbines, a portable transformer box is provided which will allow the nacelle preparation team to operate the yaw and hydraulic systems while the nacelle is grounded prior to erection.
In a first embodiment, the invention is a system for ground testing a yaw system of a wind turbine, comprising: a portable transformer device comprising a step down transformer, a case for enclosing the step down transformer, a first input voltage connection for receiving a first input voltage from a generator, a second output voltage connection for providing a second output voltage equal to the first input voltage of the generator, and a third stepped down output voltage connection for providing a third stepped down output voltage, wherein the step down transformer converts the first input voltage of the generator to the third stepped down output voltage, wherein the second output voltage connection and the third stepped down output voltage connection are adapted to be connected to a nacelle of a wind turbine for providing the necessary power for testing the yaw system while the nacelle is grounded prior to erection.
In a further embodiment, the first input voltage is approximately 690 VAC, the second output voltage is approximately 690 VAC, and the third stepped down output voltage is approximately 400 VAC. The generator for provides 690 VAC. In a further embodiment, a controller is provided that has a communication link adapted for connection to the nacelle to control the yaw system. The case may include ventilation and one or more handles for transporting the portable transformer device. The yaw system has status lights that indicate the yaw system is operational.
In a second embodiment, the invention is a system for ground testing a yaw system of a wind turbine that also includes the controller. This embodiment has a portable transformer device comprising a step down transformer, a controller having a communication link adapted for connection to a nacelle of a wind turbine to control a yaw system, a case for enclosing the step down transformer and the controller, a first input voltage connection for receiving a first input voltage from a generator, a second output voltage connection for providing a second output voltage substantially equal to the first input voltage of the generator, and a third stepped down output voltage connection for providing a third stepped down output voltage, wherein the step down transformer converts the first input voltage of the generator to the third stepped down output voltage, wherein the second output voltage connection and the third stepped down output voltage connection are adapted to be connected to the nacelle of the wind turbine for providing the necessary power for testing the yaw system while the nacelle is grounded prior to erection.
The invention also includes a method for ground testing a yaw system of a wind turbine, comprising the following steps: (a) connecting a portable transformer device to a generator having a first output voltage provided by a first output voltage connection, wherein an input voltage connection of the portable transformer device is connected to the first output voltage connection of the generator, and wherein the portable transformer device provides a second output voltage by a second output voltage connection equal to the first output voltage of the generator and a third stepped down output voltage by a third stepped down output voltage connection; (b) connecting the second output voltage connection of the portable transformer device and the third stepped down output voltage connection to a nacelle of the wind turbine; (c) connecting a controller to the nacelle for controlling a yaw system of the nacelle; (d) powering on the generator to provide the first output voltage from the generator; (e) receiving by the portable transformer device the output voltage from the generator, providing the output voltage of the generator to the second output voltage connection and stepping down the output voltage from the generator to provide the third stepped down output voltage connection to the nacelle of the wind turbine; (f) energizing the yaw system, such that the yaw system receives the second output voltage and the third stepped down output voltage from the portable transformer device; and (g) outputting an indication to status lights of the yaw system to indicate that the yaw system is operational.
In an embodiment, the first input voltage is approximately 690 VAC, the second output voltage is approximately 690 VAC, and the third stepped down output voltage is approximately 400 VAC and the generator provides 690 VAC. The method may further include connecting an output signal that indicates that the yaw system is operational to a reporting device or an alarm device. The method may further include visually inspecting the status lights to confirm that the yaw system is operational, visually inspecting the nacelle for movement to confirm that the yaw system is operational, and/or receiving an indication of movement of the nacelle to confirm that the yaw system is operational.
Other systems, methods, features and/or advantages of this disclosure will be or may become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features and/or advantages be included within this description and be within the scope of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in the following description in view of the drawings that show:
FIG. 1 is a schematic drawing depicting a typical assembled wind turbine.
FIG. 2 is a schematic diagram depicting an exemplary embodiment of a system for ground testing a yaw system of a wind turbine.
FIG. 3 is a circuit diagram of the transformer of FIG. 2 .
FIG. 4 is a schematic diagram depicting an exemplary embodiment of a system for ground testing a yaw system of a wind turbine of FIG. 2 in use.
FIG. 5 is a schematic diagram depicting another exemplary embodiment of a system for ground testing a yaw system of a wind turbine.
FIG. 6 is a circuit diagram of the transformer of FIG. 5 .
FIG. 7 is a schematic diagram depicting an exemplary embodiment of a system for ground testing a yaw system of a wind turbine of FIG. 5 in use.
FIG. 8 is a flow diagram illustrating the steps of the testing method of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Systems and methods for testing a yaw system of a wind turbine are provided, several exemplary embodiments of which will be described in detail. In a conventional manner, as shown in FIG. 1 , an assembled wind turbine 1 comprises a tower 2 , a nacelle 3 and a rotor including a hub 4 with rotor blades 5 . The nacelle 3 is rotatably mounted on the tower 2 around a yawing axle (not shown). A yaw control motor (not shown) is located between the tower 2 and the nacelle 3 to yaw the nacelle.
Referring now in more detail to the drawings, FIG. 2 is a schematic diagram illustrating an exemplary embodiment of a system for ground testing a yaw system of a wind turbine. As shown in FIG. 2 , the system comprises a portable transformer device 10 having a case 12 , input voltage connection 14 (e.g., 690 VAC), output voltage connection 16 (e.g., 690 VAC), and stepped down output voltage connection 18 (e.g., 400 VAC).
Turning now to FIG. 3 , an illustration of the transformer circuitry in an exemplary embodiment is shown, having input voltage connection 14 (e.g., 690 VAC/IN), output voltage connection 16 (e.g., 690 VAC/OUT), and stepped down output voltage connection 18 (e.g., 400 VAC/OUT). Stepdown transformer 20 steps down the input voltage from input voltage connection 14 to stepped down output voltage at output voltage connection 18 .
FIG. 4 is a schematic diagram depicting an exemplary embodiment of a system for ground testing a yaw system of a wind turbine of FIG. 2 in use. During the yawing process the turbine nacelle 3 is turned around a vertical axis until the rotor axis is, except for a possible vertical tilt angle, parallel to the wind direction. Usually the yaw axis is concentric with the wind turbine tower axis. Yawing is normally carried out by electrical or hydraulic means. The yaw drive unit control is based on a measurement of the wind direction by one or more wind direction sensors placed on the turbine nacelle. A generator 30 (usually 690 VAC trailer) may be on site to supply 690 VAC. It may also supply 110 VAC output voltage 15 for controller devices 32 which control communication through communication link 34 with the nacelle 3 . However, the necessary 400 VAC is not provided by the generator 30 . The portable transformer device 10 receives input voltage 14 from generator 30 . It provides output voltage 690 VAC to the nacelle 3 from connection 16 (e.g., 690 VAC/OUT), and stepped down output voltage 400 VAC to the nacelle 3 from connection 18 (e.g., 400 VAC/OUT). With this portable transformer device 10 , all the necessary voltage is now available on the ground for operation/ground testing of the yaw and hydraulic systems while the nacelle 3 is grounded.
Although while on the ground, the nacelle 3 would not necessarily be physically yawed due to the restraints of the nacelle stand, the ground test will provide the ability to visually check the yaw system status lights upon energizing. The portable transformer device 10 also allows verification that the crane is operational.
FIG. 5 is a schematic diagram depicting another exemplary embodiment of a system for ground testing a yaw system of a wind turbine. As shown in FIG. 5 , the system comprises a portable transformer device 10 having a case 12 , input voltage connection 14 (e.g., 690 VAC), input voltage connection 15 (e.g., 110 VAC), output voltage connection 16 (e.g., 690 VAC), and stepped down output voltage connection 18 (e.g., 400 VAC), and communication link 34 (COM/OUT) from an internal controller (not shown). The case 12 preferably include ventilation 40 , a handle for carrying the device 42 , and input controls 44 for the yaw controller. The case may further include a locking mechanism (not shown) and any necessary warning labels and the like. Outputs that indicate the yaw is operational may be provided for connection to further devices such as an alarm, a computer, a reporting tool, and the like.
FIG. 6 is a circuit diagram of the transformer of FIG. 5 , having input voltage connection 14 (e.g., 690 VAC/IN), input voltage connection 15 (e.g., 110 VAC/IN), output voltage connection 16 (e.g., 690 VAC/OUT), and stepped down output voltage connection 18 (e.g., 400 VAC/OUT). Stepdown transformer 20 steps down the input voltage from input voltage connection 14 to stepped down output voltage at output voltage connection 18 . A controller 32 is provided in the device 10 which receives 110 VAC and provides the communication link 34 (COM/OUT).
FIG. 7 is a schematic diagram depicting an exemplary embodiment of a system for ground testing a yaw system of a wind turbine of FIG. 4 in use. A generator 30 (usually 690 VAC trailer) may be on site to supply 690 VAC. It may also supply 110 VAC output voltage 15 for controller devices 32 which control communication through communication link 34 with the nacelle 3 . However, the necessary 400 VAC is not provided by the generator 30 . The portable transformer device 10 receives input voltage 14 from generator 30 . It provides output voltage 690 VAC to the nacelle 3 from connection 16 (e.g., 690 VAC/OUT), and stepped down output voltage 400 VAC to the nacelle 3 from connection 18 (e.g., 400 VAC/OUT). A controller 32 is provided in the device 10 which receives 110 VAC and provides the communication link 34 (COM/OUT). With this portable transformer device 10 , all the necessary voltage is now available on the ground for operation/ground testing of the yaw and hydraulic systems while the nacelle 3 is grounded.
With reference to FIG. 8 , a ground testing method for a yaw system of a wind turbine 1 according to an embodiment of the invention is shown. In this embodiment, the yaw system is used in a wind turbine system 1 . The testing method includes the following steps 100 to 140 .
The nacelle prep team provides a generator trailer with 690 VAC. The portable transformer device 10 is connected to the generator 30 and the nacelle 3 in step 100 . A controller 32 is provided separate from or as part of the device 10 which receives 110 VAC and provides the communication link 34 (COM/OUT) for the nacelle 3 in step 102 . The generator is powered on and the portable transformer device 10 receives input voltage 14 from generator 30 . It provides output voltage 690 VAC to the nacelle 3 from connection 16 (e.g., 690 VAC/OUT), and stepped down output voltage 400 VAC to the nacelle 3 from connection 18 (e.g., 400 VAC/OUT) in step 104 . With this portable transformer device 10 , all the necessary voltage is now available on the ground for operation/ground testing of the yaw and hydraulic systems while the nacelle 3 is grounded. Upon energizing in step 106 , the yaw system can be tested by a visual inspection of the status lights in step 108 . The nacelle attempting to yaw with slight movement may also be observed in step 108 . This is sufficient to confirm operation of the device before erection.
While various embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions may be made without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims.
|
A system and method is provided for ground testing of a yaw system of a nacelle ( 3 ) prior to erection of a wind turbine ( 1 ). A portable transformer box ( 10 ) is provided which will allow the nacelle preparation team to operate the yaw and hydraulic systems while the nacelle is grounded prior to erection.
| 8
|
BACKGROUND OF THE INVENTION
Various techniques are known for stabilizing the soil or fill beneath pavement or other structural improvement to provide a stable, high integrity base therefor. Proving of a good, highly stabilized roadbed or other load base is essential if long life of the paved layer is to be achieved or if the load base is to possess the structural integrity needed to support the improvements. A variety of "aggregates" such as crushed rock have been utilized in forming roadbeds or other fill areas. When old pavement is cracked and base reconstruction is required, the usual procedure is to excavate and haul away the old base material, haul in new base material, and dump, spread, and compact the new base material. When practical, use of binding material for in-situ reconstruction of the existing base material can be much less expensive. In addition to more conventional fill and/or binder materials, a material called "fly ash" has been used to provide stabilized roadbeds by mixing a processed product such as fly ash with whatever soil already exists where the paved layer is to be deposited. The amount of fly ash or other filler/binder material to be mixed with the pre-existing soil depends heavily upon the characteristics of that soil. Engineering specifications typically indicate a required capability for carrying weights in pounds per square inch of the pavement. Types of roadbed material, such as clay, require stabilization to eliminate the plasticity of the material. Sandy types of roadbed foundation material require both binding and/or filler to fill air voids between particles of the road base material. Many types of binder material, such as cement, sand, lime, bentonite, and the like may be utilized. Stabilization of earth below buildings or other construction sites may require filler/stabilization material. It has been the practice to move substantial amounts of road base material, for example, a four foot layer, haul it away, and replace it with four feet of new filler material with binder and/or filler already mixed in. The replacement layer then is wet down and packed as necessary to achieve the needed density. Cementitious action between the binder and replacement material provides the needed stable road bed.
Fly ash is a material that is produced as a waste product from coal-fired plants of various kinds. Fly ash is so light and powdery that if a quantity of it is dumped on a horizontal surface, the fly ash "spreads out" to more or less uniformly cover a wide area. In other words, fly ash, like talcum powder, cannot be "piled up" effectively.
The known prior technique for mixing fly ash with pre-existing soil along a proposed roadway is to spread a thin layer (approximately three inches thick) along the roadway using a truck-mounted spreading device. A fine water spray is directed to limit the amount of fly ash "dust" that is generated. Then, a tilling device, such as a BOMAG Model MPH100 Recycler/Soil Stabilizer machine, is driven along the roadway on which the fly ash has been spread. The BOMAG machine includes a number of rotary tilling blades mounted under a trailing hood. Rotation of the tiller blades mixes the fly ash with the soil being tilled. If the roadbed soil is of a quality such that a large amount of fly ash is needed to achieve the degree of stabilization or void filling needed, it may be necessary to perform four or five operations each spreading three inch layers of fly ash and then re-tilling the soil before spreading the next layer of fly ash. The multiple passes are necessary because it is impossible to spread the fly ash in a layer more than three or four inches thick; however, ten to fifteen inches of fly ash may be needed to achieve proper stabilization wherein the mixed fly ash and soil react to cement the soil into the desired stable roadbed upon which a layer of pavement can be deposited so as to produce a durable, long life, paved roadway.
The highest known rate at which fly ash has been previously mixed with pre-existing soil using a tiller is 130 tons of fly ash per day. Four to five spreader truck loads of fly ash were spread on the surface and followed by a PULVAMIXER tilling device to achieve this rate.
One prior stabilizing machine is shown in Russian Patent No. 293,094, which discloses a rotary cutter that cuts through roadbed soil or the like. The rotary cutter is surrounded by a housing. Powderized binding material is fed through a gravity operated hopper into a stream of compressed air produced from a nozzle that blows the powderized binding material into the housing around the rotary cutter and into the vicinity of the rotor. A nozzle injects water sprayed to moisten the cementing mixture. The Russian patent does not disclose use of fly ash as the bonding agent or how the machine could be modified to effectively introduce fly ash into the tilled soil. Other references, including U.S. Pat. Nos. 2,937,581 and 3,753,620 disclose use of fly ash as a binder in soil to be stabilized to provide a roadbed, but do not disclose efficient, practical ways of introducing large amounts of the fly ash into the tilled soil.
It would be highly desirable to reduce the cost of mixing the needed amount of fly ash or other powdery binder or filler material into soil along a roadbed or other construction site and to provide a suitably stabilized roadbed or other soil base upon which a paved layer can be deposited so as to provide a durable, long life paved road, foundation, or the like. It also would be desirable to make it more practical to use fly ash as a filter/binder material in such applications, because disposing of fly ash often is a big problem.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide a method for mixing a large amount of fly ash or other powdery binder, filler, or sealer material with soil for a roadbed or foundation at a substantially lower cost and in substantially less time than has been previously achievable.
It is another object of the invention to provide an improved economical tilling machine capable of efficiently mixing a large amount of fly ash with tilled soil to provide a stabilized roadbed or construction site base.
It is another object of the invention to provide a method and apparatus which provides a thick, stabilized soil base containing a large amount of fly ash or other powdery filler or binder material and water in a single pass, without generating excessive dust.
It is another object of the invention to avoid the need to remove unstable roadbed or foundation material and replace it with substitute material containing a binder or filler.
It is another object of the invention to make it practical to use available fly ash as a filler or binder material for stabilizing soil bases.
Briefly described, and in accordance with one embodiment thereof, the invention provides a method and apparatus for simultaneously tilling a sufficiently deep layer of soil along a roadway or improvement site to provide a stabilized and/or sealed soil base, mixing in a sufficient amount of fly ash or other suitable binder, filler, or sealer material and also mixing in a sufficient amount of water in the form of a spray to provide a durable, reliable, stabilized and/or sealed soil base. A water manifold mounted on the outside of a hood covering a rotary tiller which tills a thick layer of soil. A plurality of tubes extend from the water manifold through the shroud to a region above the rotary tiller, injecting a dense, uniform spray of water inside the housing, prewetting the soil base being tilled. Water is supplied by a tanker truck moving slowly alongside a tractor on which the tiller is mounted. A second manifold is mounted behind the water manifold and includes a plurality of nozzles extending through the shroud. A flexible hose conducts powdery filler or binder material from another tanker truck moving alongside the filler/stabilizer machine. The powdery filler/binder material is uniformly mixed with the prewetted soil being tilled. The dense spray of water both prewets the soil being tilled and prevents powder filler, binder, or sealer material from spreading outside the hood and causing dust/particulate pollution.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a roadbed tilling/stabilizing apparatus in accordance with the present invention.
FIG. 2 is a partial section view across section line 2--2 of FIG. 1.
FIG. 3 is a section view taken across section line 3--3 of FIG. 1.
FIG. 3A is a section view taken along section line 3A--3A of FIG. 3A.
FIG. 4 is a section view along section line 4--4 of FIG. 1.
FIG. 4A is a bottom plan view of one of the nozzles shown in FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, roadbed stabilization apparatus 1 includes a tractor 3 supporting a tiller/stabilizer machine 7. Tractor 3 is supported by its rear wheels 5 and front wheels 6 along a roadbed 9 which is to be prepared for deposition of pavement. The tilling/stabilizing machine 7 includes a rotary tiller 23 including a plurality of tines or blades as shown in FIG. 2 driven by an hydraulic motor 15 (FIG. 1). Hydraulic motor 15 is connected by a tube 17 to a hydraulic pump (not shown) in tractor 3. The tractor 3 and the portion of the tiller/stabilizer machine 7 described thus far can be a BOMAG MPH 100 Recycler/Soil Stabilizer available from BOMAG USA, Springfield, Ohio. The device is capable of tilling a roadway layer up to about 12 inches in depth. The BOMAG MPH 100 includes a manifold which is commonly used for dispensing liquid asphalt or oil into the substrate material being pulverized by the rotary tillers 23.
In accordance with the present invention, a machine such as the BOMAG MPH 100 is modified by provision of a fly ash manifold 11 and a water injection manifold 13. Fly ash injection manifold 11 is connected by a flexible hose 11A to a metering device 14 that pumps a controlled amount of fly ash into manifold 11 from a fly ash tank truck 16. Water is pumped via flexible hose 13A into water manifold 13 from a water tank truck 18. The tank truck 18 and the fly ash tank truck 16 move alongside of tilling/stabilizing apparatus 1 as it moves in the direction of arrow 12 along roadbed 9. In FIG. 1, numeral 9A designates the untilled portion of roadbed 9, and 9B designates the portion behind tiller/stabilizer machine 1 which has been tilled and simultaneously mixed with water and fly ash in accordance with the present invention to provide a roadbed (or other foundation) that becomes stabilized due to the mixing and cementitious reaction of the roadbed base material and the fly ash and water injected from the manifolds 11 and 13, respectively.
As best seen in FIGS. 2-4, fly ash manifold 14 has three large injection tubes 19 that extend through the upper surface of the housing of tiller/stabilizer machine 7. The water manifold 13 has 17 tubes 21 extending through the top surface of the tiller assembly 7. The inside diameter of fly ash manifold 11 and the base 11A is three and three fourths inches in the described prototype of the invention. The inside diameter of the outlet tubes 19 also is three and three fourths inches. The spacings indicated by dimension arrows 32 in FIG. 3 are 11 inches, the width of the surface 7A of the tiller/stabilizer apparatus 1 being equal to 7 feet. The center-to-center spacing between the three outlet tubes 19 indicated by dimension arrow 33 in FIG. 3 is 2 feet, 6 inches. Each of the three outlet tubes 19 includes four elongated, rectangular deflection vanes 36, as best shown in FIG. 3A. Each of the deflection vanes 36 has a longitudinal axis that is perpendicular to the rotary axis of tiller 23 and extends substantially across the outlet opening of tube 19. The left two deflection vanes 36 are oriented to the left, as indicated in FIG. 3A, and the right pair of deflection vanes 36 are tilted to the right, as indicated in FIG. 3A. The deflection vanes 36 can be adjustable to allow better control of the disbursion of fly ash or other filler, binder, and/or sealer material within the housing of tilling/stabilizing machine 7. The orientation of the vanes is quite important to proper mixing of the fly ash into the prewetted tilled soil. A tilt of the vanes is approximately 30° from vertical, and the dimensions are 1/4 of an inch in thickness by one inch in height, with length selected to extend across the outlet opening of tube 19. The spacings designated by dimension arrows 38 in FIG. 3A are selected to be approximately equal. The length of the tubes 19 is 10 inches, 8 inches of which is above the surface 7A.
The inside diameter of water manifold 13 is two inches. The inside diameter of the tubes 21 is three-fourths of an inch. The lower ends 21A are crimped as indicated in FIG. 4A, to a generally elliptical configuration, wherein the dimension indicated by numeral 37 is approximately one half of an inch, and the major elliptical axis is parallel to the rotary axis of tiller 23. The center-to-center spacings between the tubes 21 is 4.35 inches, and the outer tubes 21 are approximately 5 inches from the opposed edges of the housing of tilling/stabilizing machine 7. As best seen in FIG. 2, tubes 21 are tilted forward five to ten degrees. Tubes 21 are 10 inches long, 8 inches of which is above the supporting surface 7A of the housing.
The above described configuration of the water manifold 13 is located forward relative to the fly ash manifold 11, approximately six inches to the right of axis 18, as indicated by dimension arrows 31 in FIG. 2. This placement of tubes 21 and providing the large number of nozzles 21 under hood 7A was found to be important to the workability of the invention. More specifically, this was found to be necessary to properly "prewet" the soil being tilled by a uniform spray of water above the tiller 23. In order to achieve the necessary dust control, it was necessary that the spray be uniformly spread throughout the inside of hood 7A. It was also necessary to avoid "clotting" of fly ash material with water before mixing due with the roadbed material occurs. The optimum placement for the fly ash manifold 11 was found to be approximately 8 inches behind the rotational axis 18 of tiller 23, as indicated by dimension arrows 30 in FIG. 2.
EXAMPLE
The tiller/stabilizer machine of FIGS. 1-4 was used to tear up and remove the several inches of old asphaltic concrete pavement. Then using the machine of FIG. 1, an 8 inch layer of the roadbed was tilled. Fly ash was fed into fly ash manifold 11 at the rate of approximately 21 pounds per sq. ft. This amount of fly ash is equivalent to an 8 inch layer of fly ash being mixed into the 8 inch tilled layer 9B (FIG. 2). Water was fed into the manifold 13 at a rate of approximately 2 gallons per sq. ft. A BROS. TT sheepsfoot roller was utilized to compact the in situ base material as needed to achieve the desired density of the roadbase material. In this case, the initial roadbed density was relatively low, at 117.6 pounds per cu. ft. Approximately 20 pounds of fly ash per square foot of roadbed surface area were required to provide suitable void filling and stabilization of roadbed 9 so that it would withstand a load of 650 pounds per square foot. Utilizing a grading machine, the surface was graded and shaped as required to bring the roadbed surface to a specified level. A rubber tire roller was utilized to effectuate final compaction to 100% Proctor. The roadbed surface was kept wet. The nozzles at the ends of tubes 21 produced a dense, uniform spray or mist throughout the hood or housing of tiller/stabilizer unit 7, resulting both in essential dust control and cementitious binding action of the fly ash mixed with the pre-existing roadbase material. Proper placement of the fly ash nozzles and the water spray mist and providing sufficient water pressure in the manifold 11 to effectuate the spray were found to be essential to achieve both good dust control and adequate supply of water to be mixed with the fly ash and the base material being tilled.
The above example resulted in mixing 364 tons of fly ash into the roadbed in a single day, more than twice the previous amount of 130 tons per day previously achievable, thereby resulting in a substantial savings in the construction of the roadbed. The need to use an expensive spreader was avoided, and two fewer workers were required than if prior fly ash stabilization procedures had been used.
While the invention has been described with reference to a particular embodiment thereof, those skilled in the art will be able to make various modifications to the described apparatus and method without departing of the true spirit and scope of the invention.
|
A tilling/stabilization apparatus for tilling and stabilizing a roadbed or other base layer of soil includes a large manifold for receiving metered amounts of pressurized fly ash or other powdery filler, binder, and/or sealer material and injecting it in the vicinity of a rotating tiller that is tilling the roadbed. A water manifold passing through a housing surrounding the tiller produces a dense water mist inside the housing, causing dust to settle and providing a cementitious mix of the fly ash with the tilled roadbase material. Reliable, economical filling of roads and stabilization of a road base is achieved.
| 4
|
SECTOR OF THE INVENTION
[0001] The present invention relates to a method and an apparatus for systems for electrostatic powder coating that exploits the use of a carrier fluid constituted by air deprived of undesirable substances, together with ionization and heat conditioning of said carrier fluid.
[0002] In greater detail, the invention relates to a method and an apparatus for coating that uses as paint-carrier fluid a mixture rich in nitrogen/oxygen/argon obtained continuously from compressed air during coating.
PRIOR ART
[0003] As is known, the current state of the art in powder-coating systems envisages a corona-effect electrostatic-spray system, where positioned in the terminal part of the guns are one or more needles that yield a charge to the powder to be attracted onto the products to be coated, or else with the system known as “tribo” with which the powder is charged by rubbing in a purposely provided tube.
[0004] In either case, the operating coating steps envisage entrainment of the powder, movement of the fluidized bed, atomization/nebulization of the powder, and sending of the electrostatically charged powder onto the substrate to be coated. It is also known that peristaltic recovery of the dispersed powder is commonly obtained with compressed air produced by a normal compressor.
[0005] One of the known drawbacks is represented by the fact that the compressed air used entrains along with it elements that are harmful for a perfect, distribution penetration, and flow of the powder over the substrates to be coated, such as, for example, humidity, particles of hydrocarbons due to the compression of the air and particles in suspension present in the atmospheric air.
[0006] Even though the coating operation is carried out in purposely designed spray booths or protected environments, the substrates to be coated undergo the effect of the relative humidity of the environment. This problem is much felt in so far as it gives rise to microbubbles that form between the substrate and the film of coating, and over time cracks may arise in the film itself with consequent problems of quality and detachment of the film.
[0007] In this connection, it must in fact be recalled that, according to the reference tables of the U.S. International Standard Atmosphere, environmental air is made up as follows:
[0000]
TABLE A
Ambient Air Specification (U.S. International
Standard Atmosphere)
Substance
Symbol
Value
Unit
Nitrogen
N 2
78.080
vol. %
Oxygen
O 2
20.944
vol. %
Argon
Ar
0.934
vol. %
Carbon Dioxide
CO 2
350/360
ppmV
Neon
Ne
16.1
ppmV
Helium
He
4.6
ppmV
Kripton
Kr
1.08
ppmV
Xenon
Xe
0.08
ppmV
Methane
CH 4
2.2
ppmV
Hydrogen
H 2
0.5
ppmV
Nitrogen Protoxide
N 2 O
0.3
ppmV
Carbon Monoxide
CO
0.2
ppmV
Ozone
O 3
0.04
ppmV
Ammonia
NH 3
4
ppbV
Sulphur Dioxide
SO x
1.7
ppbV
Nitrogen Oxide
NO x
1.5
ppbV
Hydrogen Sulphide
H 2 S
0.05
ppbV
Total Organics (other than Methane)
<10
ppmV
Other Acid Gases (HCl, etc.)
<0.1
ppmV
Dust
5
mg/Nm 3
Water
H 2 O
<65
g/Nm 3
[0008] From these premises there follow the problems typical of conventional powder coating, which uses air without any treatment as carrier fluid for the steps of management of the powder fluidized bed, entrainment, nebulization, and peristaltic recovery.
[0009] The contamination by humidity, the vesicular pollution from the hydrocarbon residue, as likewise the oily organic substances, moreover yield as a consequence formation of aggregates and accumulations of powder, difficulty of entrainment thereof in the distribution ducts, and non-homogeneity of nebulization and perfect spreading of the powder and lack of uniformity in the thicknesses with consequent difficulty in flow of the coating.
[0010] Furthermore, typical of electrostatic powder coating or liquid coating is the formation, in the corners or at the ends of perforations present in the product to be coated, of the Faraday-cage effect, which does not allow uniformity or a perfect distribution, penetration, and flow of the powder, in certain cases causing the absence of coating product, such as for example in the corners or fins typical of electric motors or of heating bodies such as radiators or components of electrical household appliances and steel structural work in general.
[0011] Also known are the difficulties in currently available systems of electrostatically charging very fine powder in order to obtain high-quality finishes. It is in fact difficult to get fine-grain powder and nanometric powder to be charged and to maintain the charge prior to impact on the products for a perfect nebulization and homogeneous distribution over the surfaces or products of various nature under the effect of the electrostatic charge.
[0012] Also known are the problems in systems for fine-powder or nanometric-powder coating that use as carrier traditional compressed air, which entrains along with it pollutant elements (amongst which particles of hydrocarbons, particles of water, and pollutant dust of various nature) that render difficult perfect distribution, penetration, and flow of the powder over the surfaces.
[0013] In spite of all the aforesaid drawbacks, known systems in any case use as carrier fluid for the powder mere compressed air even though it entrains along with it particles of humidity, particles of oil vapours, and volatile particles present in the atmosphere, thus causing the problems referred to above.
PURPOSE OF THE INVENTION
[0014] A first purpose of the present invention is thus to propose an apparatus and a method for electrostatic powder coating that will be free from the aforesaid drawbacks of known systems.
SUMMARY OF THE INVENTION
[0015] The above and further purposes have been achieved with a method and an apparatus for electrostatic powder coating according to one or more of the annexed claims, which envisages use, as carrier fluid, of a mixture of nitrogen/oxygen/argon obtained continuously, during the coating process, from compressed air that is modified and then used for movement of the fluidized bed, entrainment of powder, nebulization, peristaltic recovery, electrostatic pre-charge with positive or negative ions of the powder starting from the fluidized bed.
[0016] In greater detail, the air is “modified” in the sense that, starting from the natural composition of the environmental air referred to above, to implement the invention the latter is almost totally deprived of oxygen and totally freed of other undesirable substances present in the natural composition, thus obtaining a mixture made up exclusively of nitrogen/oxygen/argon in the preferred percentages referred to hereinafter, which also favour a synergistic effect with ionization and heat conditioning of the carrier fluid described hereinafter.
[0017] As preferred, but not indispensable, solution for implementing the invention, said mixture is obtained by means of hollow-fibre osmotic separation membranes or by means of carbon molecular sieve (CMS) using the pressure-swing-absorption (PSA) system.
[0018] A first advantage of the invention lies in the fact that, using, as carrier, air thus modified enriched in nitrogen/oxygen/argon, the velocity of thrust increases considerably and creates a less turbulent and faster flow, which is less affected by atmospheric agents such as humidity and thus enables a better and more uniform distribution of the product on the surfaces.
[0019] A second advantage is represented by the fact that the mixture obtained from air modified in nitrogen/oxygen/argon is substantially anhydrous, and hence free from humidity and particles of hydrocarbons that are at the origin of vesicular pollution of coating products.
[0020] A further advantage is represented by the fact that, using the nitrogen/oxygen/argon mixture and with pre-charging, keeping at a suitable temperature both the fluidized bed and the spray guns, it is also possible to diversify two or more outlets kept at different outlet temperatures that can be optimized for different areas of coating of the product and reduce the coating times in any circumstance. This in fact enables a higher velocity of the reciprocator device that moves the guns for supplying the powder in order to obtain greater uniformity and larger thicknesses in shorter times, and major advantages are achieved in saving of the coating powder and higher productivity in particular in robotized systems.
[0021] A further advantage is represented by the fact that, since the nitrogen/oxygen/argon mixture has a higher velocity, an impact that enables better adherence of the powder on the products is created, thus achieving a better adhesion/penetration and flow of the powder, there being impressed on the spray fan a perfect nebulization without dispersion of the powder at the ends of the fan, limiting the rebound effect thanks to the possibility of using smaller nozzles mounted on the guns as compared to the use of traditional compressed air.
[0022] The above advantage is particularly felt in the case of robotized systems since it reduces the negative effect of the movement of the spray guns.
[0023] Yet another advantage is represented by the fact that the use of air modified in nitrogen/oxygen/argon guarantees a perfect homogeneity of the movement in the fluidized bed given that said mixture is itself, anhydrous and consequently optimal entrainment of the powder in the distribution ducts as far as the guns is achieved.
[0024] Yet a further advantage of the invention is the possibility of using waste residual powder, pre-treated in previous coating cycles.
[0025] Currently, in fact, the residual powder can no longer be used in a percentage that ranges between 15% and 30%, and its recovery leads to considerable saving from an economic and environmental point of view.
[0026] According to a further advantageous use of the invention, the nitrogen/oxygen/argon mixture obtained from compressed air that will be used for moving the fluidized bed and entraining the powder and for atomization/nebulization is pre-charged with positive or negative ions upstream of the fluidized bed, or else is made to be statically neutral (namely, in the plasma state, created by annulling the positive and negative charges in a purposely provided de-ionizing chamber) in order to impose a pre-charge on the powder prior to its outlet from the gun by acting on the particles of argon and of residual oxygen present in the mixture used as carrier in order to annul the Faraday-cage effect.
[0027] Advantageously, the fact of moving the powder and imposing a pre-charge with positive or negative ions already in the fluidized bed using anhydrous mixtures of nitrogen/oxygen/argon leads to a better nebulization and a distribution with greater uniformity of the thicknesses owing to the combined synergistic effect between pre-charge and final charge that is exerted by the guns in the nebulization stage.
[0028] Yet a further advantage of the invention is the elimination of the above-mentioned problems regarding systems for fine-powder or nanometric-powder coating that use traditional compressed air as carrier.
[0029] According to yet a further advantageous use of the invention, the carrier fluid may be heat-conditioned both by heating and by cooling using purposely provided devices, for example, a chiller or other cooling devices, such as with an ultracompact plate heat-exchanger formed by an air-air exchanger equipped with evaporator and a slow-flow separator for example, a demister, with the function of keeping the temperature of the flow at a value of roughly between −15° C. and 45° C., preferably 5°-20° C. throughout the year in order to obtain in any environmental condition a perfect atomization/nebulization of the powder. In particular, the higher temperatures, close to 45-50° C. or higher, favour the step of drying of the powder-coated products in an oven.
[0030] According to a further aspect of the invention, the carrier fluid is heat-conditioned both by heating and by cooling and then mixed to a liquid paint in a spray painting apparatus to keep a desired temperature.
LIST OF DRAWINGS
[0031] The above and further advantages will be better understood by any person skilled in the branch from the ensuing description and from the annexed drawings, which are provided merely by way of non-limiting example and in which:
[0032] FIG. 1 is a schematic view of a first embodiment of an apparatus according to the invention, with ionization by means of the corona effect;
[0033] FIG. 2 is a schematic view of a first embodiment of an apparatus according to the invention, with ionization using the tribo system;
[0034] FIG. 3 is a schematic illustration of a plant with peristaltic recovery of the powder from a paint-spray booth; and
[0035] FIG. 4 is a schematic illustration of a step of separation of gases from the air performed using a hollow-fibre membrane;
[0036] FIG. 5 is a schematic view of a spray painting apparatus according to the invention, with ionization and thermal conditioning of a carrier fluid to be mixed with liquid paint.
DETAILED DESCRIPTION
[0037] With reference to the drawings, an apparatus and a method according to the invention are now described.
[0038] In the example of embodiment illustrated, a source 3 of a fluidifying fluid is provided, which gives out into a container 2 containing an amount of coating powder 4 .
[0039] The fluid has the function of maintaining in dispersed and non-agglomerated form the powder that is to be sprayed on a substrate to be coated 1 .
[0040] The container 2 communicates downstream with an atomizer device 18 , which in turn communicates with a source 13 of atomization/nebulization fluid and a source 5 of a carrier fluid under pressure, which, via an appropriate pipe 6 , is to convey the flow of carrier fluid and atomized powder to a spray nozzle 7 of a gun 17 , capable of delivering a coating fan 16 .
[0041] Moreover provided upstream of the nozzle 7 are means 8 , in themselves known, for electrostatically charging the flow of carrier fluid and powder.
[0042] In different embodiments, the means 8 may be constituted by an electrode 8 supplied at a high voltage 12 set in the proximity of the nozzle 7 ( FIG. 1 ) or by a tribo tube traversed by the flow of carrier fluid and powder ( FIG. 2 ) in contact with the walls of the tube.
[0043] According to the invention, the sources 3 , 5 and/or 13 of fluid are sources of a mixture of nitrogen/oxygen/argon made up of nitrogen in a range of 80-98 vol %, oxygen in a range of 1-90 vol %, argon in a range of 1-2 vol %, more preferably nitrogen in a range of 90-96 vol %, oxygen in a range of 4-10 vol %, argon in a range of 1-2 vol %.
[0044] Thanks to the invention it has been found (Table 1) that, whereas the velocity of the compressed air at a pressure of 1 bar (as in conventional systems) is of 7.24 m/s with a turbulence of 43.41%, using the mixture of nitrogen and oxygen with 0.9% of argon the velocity increases from 7.24 m/s to 13.17 m/s, reducing the turbulence to 35.79%.
[0045] Advantageously, the coating powder, if pushed by a less turbulent and faster carrier fluid, is less affected by atmospheric agents, such as humidity, and thus enables a better and more uniform distribution of the powder over the surface of the substrate 1 .
[0000]
TABLE 1
Channel 1
Channel 2
Channel 3
COMPRESSED AIR
Velocity Mean (m/sec)
7.2452
0.0000
0.0000
Velocity RMS (m/sec)
3.1451
0.0000
0.0000
Turbulence Intensity (%)
43.41
0.00
0.00
Frequency Mean (MHz)
5.1257
0.0000
0.0000
Frequency RMS (MHz)
0.4886
0.0000
0.0000
Frequency TI (%)
9.53
0.00
0.00
Gate Time Mean (usec)
10.71
0.00
0.00
Gate Time RMS (usec)
10.64
0.00
0.00
Data Rate (Hz)
9033
0
0
Valid Count
5000
0
0
Invalid Count
0
0
0
Elapsed Time (sec)
0.8304
NITROGEN
Velocity Mean (m/sec)
13.1753
0.0000
0.0000
Velocity RMS (m/sec)
4.7149
0.0000
0.0000
Turbulence Intensity (%)
35.79
0.00
0.00
Frequency Mean (MHz)
6.0470
0.0000
0.0000
Frequency RMS (MHz)
0.7325
0.0000
0.0000
Frequency TI (%)
12.11
0.00
0.00
Gate Time Mean (usec)
6.08
0.00
0.00
Gate Time RMS (usec)
4.58
0.00
0.00
Data Rate (Hz)
5530
0
0
Valid Count
5000
0
0
Invalid Count
0
0
0
Elapsed Time (sec)
1.3566
[0046] According to a further advantageous aspect of the invention, the source 3 of fluidifying fluid is a source of a mixture as described above, which enables, thanks to the anhydrous nature of nitrogen, a better fluidity of the powder in the container to be obtained, preventing the presence of humidity and the formation of agglomerates.
[0047] As further characteristic of the invention, the apparatus moreover comprises means 11 set upstream of said container 2 for electrostatically charging said flow of fluidifying fluid, constituted preferably by the mixture described above, prior to its entry into the container.
[0048] Advantageously, this solution enables an increase in the pre-charge of positive or negative ions of the powder in a simple way and without the use of ionization systems integrated in the fluidized bed.
[0049] In addition to improving the conditions of the fluidized bed, the pre-charge advantageously enables an increase in the electrostatic charge of the flow of mixture and powder prior to its outlet from the spray nozzle and hence elimination or considerable limitation of the Faraday-cage effect for coating points that are difficult to access, such as corners or recesses in metal bodies.
[0050] According to a further characteristic of the invention, there is envisaged the use of one or more heat conditioners 10 , 19 set preferably upstream of the container 2 and/or of the gun 17 in order to maintain said mixture and the flow of mixture and atomized powder at a desired temperature, for example a temperature of between −15° C. and 45° C., preferably 5°-20° C. Moreover, according to the invention there is afforded the possibility of conditioning and regulating the temperature of the flow of fluid and atomized powder upstream of the spray guns in order to optimize the temperature according to the environmental conditions and the substrate to be coated. Preferably, regulation of the temperature is obtained by a heating device, for example a reservoir with electrical resistances traversed by the fluid, possibly connected to the guns via a conveying tube 60 equipped with means for heating the fluid, for example electrical resistances of a helical shape for a better heat exchange and time of contact set inside the tube.
[0051] Preferably, the working mixture is a mixture of gases obtained from air modified in nitrogen/oxygen/argon produced with hollow-fibre membranes (see diagram of FIG. 4 ) or with an activated-carbon system referred to as PSA (pressure-swing absorption) at a constant temperature of −15° C. and 45° C., preferably 5°-20°.
[0052] With reference to the preferred embodiments illustrated in the attached drawings, operation of the apparatus according to the invention envisages supplying a working fluid constituted by the mixture described above in the container 2 , into which an amount of coating powder 3 has been introduced.
[0053] Introduction of the mixture, which is electrostatically pre-charged, determines formation of a fluidized bed constituted by powder and mixture.
[0054] Inserted in the container 2 is a tube 14 , which at the other end communicates with an atomizer 18 . Extracted through the tube is a flow made up of working fluid and powder recalled into the atomizer by the mixture entering the atomizer from the source 5 and exiting towards the gun 17 through the pipe 6 .
[0055] From the container there is moreover provided a discharge outlet 15 for the mixture and the residual powder.
[0056] In the case of FIG. 1 , also giving out into the atomizer 18 is the source 13 , which carries a pressurized flow of mixture that is designed to guarantee proper entrainment of the powder to the gun.
[0057] Once again in the case of FIG. 1 , provided in the proximity of the spray nozzle 7 is an electrode 8 supplied by a high-voltage generator for electrostatically charging the outgoing flow of mixture and powder.
[0058] At the same time, the substrate 1 to be coated is kept at a neutral voltage (earthed) in such a way that the flow of mixture and atomized powder impinges upon it and forms the coating layer.
[0059] Preferably, the mixture entering the container and/or the flow of mixture and powder reaching the gun 17 are thermally conditioned to maintain a temperature of between −15° C. and 45° C. irrespective of the conditions of external temperature and the period of the year.
[0060] Illustrated in FIG. 2 is an apparatus with an operation similar to the one just described, but in which the flow of carrier mixture is delivered by the source 13 upstream of a tribo tube 20 , of a type in itself known, in which both the carrier mixture and the flow of mixture and atomized powder converge in such a way as to be charged positively by contact prior to being sent on to the substrate 1 by the spray nozzles 7 .
[0061] The invention thus achieves the important advantages listed below.
[0062] A. Since the mixture described above, obtained from air modified in nitrogen/oxygen/argon is anhydrous, it is thus free from humidity and particles of hydrocarbons that lie at the origin of vesicular pollution of coating products, with a velocity of 13.17 m/s.
[0063] B. Since the carrier fluid is heat-conditioned via purposely designed heating and/or cooling equipment, it achieves the purpose of obtaining a perfect atomization/nebulization of the powder and ensuring a constant temperature throughout the year, for example by means of a chiller capable of maintaining the temperature of the fluidized bed at a value of between −15° C. and 45° C.
[0064] C. The mixture of nitrogen/oxygen/argon obtained from compressed air that is used for moving the fluidized bed in the container and/or entrainment of the powder and atomization/nebulization thereof is pre-charged with positive or negative ions in order to impose a pre-charge on the powder prior to exit thereof from the nozzle of the spray gun. The electrostatic pre-charge, by acting on the particles of argon and residual oxygen present in the carrier mixture eliminates the Faraday-cage effect described above;
[0065] D. The nitrogen/oxygen/argon mixture is faster than the compressed air used conventionally and creates an impact of the powder that thus adheres better to the products, creating a better adhesion and flow of the powder, impressing on the spray fan a perfect nebulization without any dispersion of the powder at the ends of the fan as a result of the movement of the guns, as occurs for example in robotized systems.
[0066] E. The use of air modified in nitrogen/oxygen/argon guarantees a perfect homogeneity of nebulization in the fluidized bed given that the mixture is anhydrous, and also perfect entrainment thereof in the tubes for distribution to the guns.
[0067] F. The nitrogen/oxygen/argon jet eliminates the relative humidity present in the products, which prevents perfect adhesion of the powder and creation of microbubbles.
[0068] G. The use of the nitrogen/oxygen/argon mixture eliminates any problem regarding formation of masses or aggregates of powder in the fluidized bed, given that the latter is anhydrous, i.e., free from humidity.
[0069] Advantageously, according to the invention it may moreover be envisaged that the flow of the working mixture is distributed for use via tubes coated with conductive polytetrafluoroethylene (PTFE) with glass-fibre filler, for example the material marketed under the trade name Teflon®, in so far as with said solution the ions that are conveyed within the tube are not dispersed.
[0070] Teflon consequently eliminates the problem of dispersion of the ions of the carrier mixture along the path within the tube.
[0071] Described schematically with reference to FIG. 3 is a plant for coating a substrate 1 in a paint-spray booth 25 , where the powder 4 emitted by the guns 17 is gathered by a hopper 26 set underneath the grill 30 of the plane of coating and is carried, via a first duct, to an accumulation container 28 and, via a second duct 29 , to a fluidized-bed container 2 according to the invention. Advantageously, thanks to the invention, the powder 4 gathered by the hopper is carried by an electrostatically charged mixture of nitrogen/oxygen/argon, which reduces the formation of agglomerates and improves the efficiency of the recovery of the powder.
[0072] FIG. 5 schematically shows a spray painting apparatus 40 according to a further aspect of the invention to paint a support 50 .
[0073] Apparatus 40 comprises a source 41 of a pressurized carrier fluid capable of being ionizied. Preferably the carrier fluid is a gas mixture made up of nitrogen in a range of 80-99.9%, preferably 80-98%, oxygen in a range of 1-90%, argon in a range of 1-2%.
[0074] The carrier fluid is sent through conduits 42 to a spray gun 43 to be mixed with a liquid paint contained in a reservoir 48 and to form a painting mixture to be sent onto the support 50 .
[0075] Before reaching the spray gun, the carrier fluid is heat conditioned by a thermal conditioning device 44 able to both heat and cool the carrier fluid to maintain a painting temperature between −15° C. and +45° C., preferably between 5° C. and 20° C., irrespective of the environment temperature conditions.
[0076] Preferably the heating means of device 44 comprise electric resistance devices and the cooling means comprise a chiller or other cooling devices, such as with an ultracompact plate heat-exchanger formed by an air-air exchanger equipped with evaporator and a slow-flow separator for example, a demister.
[0077] The thermoconditioning device 44 is controlled by a control unit 45 . Temperature sensors 46 , 47 may further be provided to sense the temperature of the carrier fluid and/or of the environment and to adjust in response the heating and/or cooling of the carrier fluid to reach and to maintain the desired painting temperature.
[0078] The apparatus 40 further comprises a inonization unit 51 for ionization of the carrier fluid with positive and/or negative ions according to the desired final charge, whether positive, negative or neutral, or in the plasma state, also in relation of the static nature of the support 50 , by example whether support 50 is made of a metallic or plastic material.
[0079] The present invention has been described according to preferred embodiments, but equivalent variants may be devised, without thereby departing from the sphere of protection of the invention.
|
A device and method for electrostatic powder coating include: obtaining continuously a working fluid constituted by air deprived of undesirable substances; supplying the working fluid, between 0.5 bar and 10 bar, in a container containing an amount of coating powder; extracting from the container; a first flow made up of working fluid and powder; atomizing the first flow with working fluid at a pressure of between 0.5 bar and 10 bar; supplying working fluid at a pressure of between 0.5 bar and 10 bar to create a second transport flow made up of working fluid and atomized powder; charging the second flow electrostatically under pressure; and sending the second electrostatically charged flow of working fluid and atomized powder onto a substrate, at a temperature of between −15° C. and +45° C., and a device and method for electrostatic painting including heating/cooling temperature adjustment of the painting mixture.
| 1
|
RELATED APPLICATIONS
This is a continuation-in-part of application Ser. No. 09/566,538, filed May 8, 2000, U.S. Pat. No. 6,390,101.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
BACKGROUND OF THE INVENTION
The present invention relates to devices for applying a fluid, and in particular to devices for applying fluid to hair.
In the past, there has been a great need applicators for applying fluid to hair. For example, many people desire to have their hair straightened. One fluid used for straightening hair is Sodium Hydroxide, or lye. When applying hair straightening fluids (commonly called “relaxers”) to the hair, the hairdresser applies relaxer one section of the hair at a time and uses his fingers or the backside of a brush to smooth the hair. Due to the chemicals in the relaxer and the smoothing technique, the hair thus becomes straightened. This procedure is desirable for people with curly hair who wish to have straight hair. The procedure is particularly desirable for people with ethnic or racial backgrounds having very curly hair, for example African-Americans.
While other applicators exist, there exists a need for a self-contained applicator with a well-controlled dispensing slot and an apparatus for smoothing integral with the applicator. Moreover, it is desirable to have an applicator that has the capability of being connected to several different sizes of combs (for varying thicknesses of hair). For example, different types of hair have varying thicknesses of hair, such as round-celled hair (straight), oval shaped hair (wavy) and flat cell hair (curly). Different combs are desirable to be used with these varied thicknesses.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved applicator for applying relaxer or other fluids to hair.
It is another objection of the invention to provide a self-contained applicator.
It is a further object of the invention to provide an applicator capable of both applying and smoothing a fluid onto hair.
In one embodiment, the apparatus includes a reservoir for containing a fluid, sidewalls defining the reservoir, the sidewalls forming an elongate curvilinear cavity along an interior surface and forming an exterior surface. The cavity includes the reservoir and has a top portion and a bottom portion and the cavity also has a longitudinal axis. The applicator also includes a top endwall located at the top portion of the sidewalls, wherein the endwall includes an elongate cavity for dispensing a fluid. A flexible lip is located adjacent the cavity for assistance in dispensing a fluid from the elongate cavity is also included in the applicator. The applicator also includes a movable bottom endwall for containing the fluid within the reservoir and advancing fluid and a rotatable smoothing rod attached to the exterior surface of the sidewalls.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a side view of an applicator according to a particular embodiment of the invention.
FIG. 2 is top view of a cross-section of an applicator according to a particular embodiment of the present invention.
FIG. 3 is a top view of a dispensing end of the applicator according to three alternative embodiments of the invention.
FIG. 4 is a partially exposed side view of an applicator according to a particular embodiment of the invention.
FIG. 5 is a perspective view of a rattail comb according to a particular embodiment of the present invention.
FIG. 6 is a perspective view of a rattail comb according to a particular embodiment of the present invention.
FIG. 7 is a diagrammatical top view of an applicator according to a particular embodiment of the present invention.
FIG. 8 is a diagrammatical top view of an applicator according to a particular embodiment of the present invention.
FIG. 9 is a partial perspective view of an applicator according to a particular embodiment of the present invention.
FIG. 10 is a partial perspective view of an applicator according to a particular embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the preferred applicator 100 is shown. The applicator 100 includes a body 102 having sidewalls 104 , a dispensing end 106 and a non-dispensing end 108 . A driver 109 is located adjacent the non-dispensing end 108 . The top surface 106 includes an elongated slot out 110 and a lip 112 adjacent the slot 110 , protruding from the dispensing end 106 . The applicator 100 also includes a comb or brush 112 having a rattail 113 . The comb 112 is secured to the applicator 100 by two retaining tracks 114 , 115 . The preferred applicator further includes a roller 116 attached to the applicator using two similarly constructed supports 118 .
In the preferred embodiment of FIG. 1, the sidewalls 102 form an elongate curvilinear-shaped object with an oval cross-section. In this illustrated embodiment, the sidewalls 102 actually form one continuous wall extending the perimeter of the applicator. The interior of the applicator 100 , and thus inside the sidewalls 102 , contains the fluid sought to be dispensed from the slot 110 . Attached to the sidewall 102 of the preferred applicator 100 are two supports 118 , 119 for securing a smoothing rod 116 to the applicator 100 . The function of the smoothing rod 116 will be further discussed below. Attached to the other side of the sidewall 102 in the preferred embodiment are vertically aligned tracks 114 , 115 for securing a comb or brush 112 to the applicator 100 . The location of the tracks 114 , 115 is preferably opposite the supports 118 , 119 and smoothing rod 116 in order to allow free movement of the rod 116 and freedom to use the comb 112 without interference. A lip 112 is preferably attached to the top surface 106 of the applicator 100 . The lip 112 is located adjacent the dispensing slot 110 for reasons that will be further discussed below.
The dispensing slot 110 is elongated so as to permit the fluid retained within the applicator 100 to be dispensed in a wide path. The lip 112 then assists in spreading the fluid dispensed from the slot 110 uniformly. For example, as fluid is forced out of the slot 110 , as will be further discussed below, the fluid advances onto the lip 112 and is ideally spread evenly across the hair across which the lip 112 and slot 110 move. In alternative embodiments shown in FIGS. 3 a and 3 b , brush bristles 302 or teeth 304 may alternatively be attached adjacent the dispensing slot 110 . Bristles 302 may be particularly desirable if bleach or hair color is being applied and teeth 304 may be desirable for use with hair gel. In any event, the slot 110 and structure for assisting in applying the fluid to the hair is preferably located on the dispensing end 106 (which is preferably part of a removable cap), rather than the sidewalls 102 . Having this structure on the dispensing end permits the applicator 100 to be used with multiple endcaps, each containing the different structure, such that one applicator may be used for applying several different fluids.
The dispensing end 106 is preferably convex in shape so that the dispensing slot 110 is centrally located at the highest spot on the end 106 and the lip 112 is adjacent the slot. The convex shape assists the user in applying the fluid, for example relaxer, to the head because it permits the user to place the curved end 106 onto the hair, allowing a slight separation of the slot 110 from the scalp. The separation is desirable because of the damage relaxer can do if placed directly onto the scalp. In an alternative embodiment, the applicator 100 includes two nobs 306 , which are raised with respect to the dispensing end 106 (as shown in FIG. 3 a ), to achieve separation between the slot 110 and the hair.
The rod 116 is secured to the applicator 100 by supports 118 , 119 and preferably extends vertically along the sidewall 102 . The rod 116 is secured by the supports 118 , 119 such that it is free to spin about its axis. As a result, the user may roll the smoothing rod along the hair after the fluid has been applied to the hair. When straightening hair, for example, this has the desired result of permitting the scalp to be used as the “ironing board” for the hair to be pressed against. This is a significant improvement over the present method in which the user straightens or flattens the hair using his or her thumbs or the backside of a brush.
Another desired feature of the applicator 100 is the telescoping rattail, or parting wand, 113 extending from the comb 112 or non-dispensing end 108 of the applicator 100 . The rattail or parting wand 113 is used to part hair, for example to separate different sections of hair for relaxer to be applied to the separate portions. The telescoping feature permits the wand 113 to be placed out of the way when a fluid, such as relaxer, is being applied to the hair, and to be extended only when needed. The telescoping feature also permits the wand to be extended to differing lengths, thereby adapting to the user's preference.
Turning now to FIG. 2, that Figure provides a look at a cross-section of the sidewalls 102 . The sidewalls 102 have an interior surface 202 a and an exterior surface 202 b . A movable endwall 204 and a driving shaft 206 are also shown in FIG. 2 . The movable endwall 204 and interior surface 202 a of the sidewalls 102 forms a reservoir for containing a fluid, such as relaxer, within the applicator 100 . When more fluid is desired to be pushed from the slot 110 , the user may turn the driver 109 , which turns the driving shaft 206 . The driving shaft 206 is threaded like a screw and drives the movable endwall 204 up and down as the driver 109 is turned. When the driver 109 is turned, the movable endwall 204 thus decreases the size of the reservoir and forces fluid toward the dispensing end 106 and out through the slot 110 , preferably onto the subject's hair. While the driver 109 and driving shaft 206 combination is the preferred structure for advancing fluid to and out of the dispensing slot 110 , other methods for advancing the fluid may be used. For example, the movable wall 204 may be secured within the inner surface 202 a using a friction fit or other method. The applicator 100 may also use a pushable button or device, for advancing a movable wall, which is located on the sidewall 102 . This arrangement may permit the user to more easily dispense fluid while he or she is applying the fluid. Ultimately, it is desired that the dispensing end 106 include a removable cover to permit replacement of fluid within the applicator 100 when the applicator 100 is empty or low on fluid.
Turning now to FIGS. 3 and 4, FIG. 3 presents a top view of the dispensing end 106 , including the elongated dispensing slot 110 and the lip 112 . FIG. 4 illustrates the interior of the preferred applicator, including the driver 109 , shaft 206 and movable endwall 204 . The fluid fills the interior cavity of the applicator 100 and the top surface is shown near the dispensing end 106 .
During use, the applicator 100 is preferably tipped upside down, causing the fluid sought to be dispensed onto the hair. After the fluid is placed on the hair, the user may tip the applicator 100 on its side and use the smoothing rod 116 to smooth, spread or apply the fluid evenly (if desired) onto the hair. As a result, depending on how the user holds the applicator 100 , he or she may wish to detach the comb 112 , collapse the wand 113 , or not even have the tracks 114 , 115 present on the applicator 100 for easy holding of the applicator 100 . Moreover, the fluid is preferably viscous enough such that it does not automatically exit the slot 110 when the applicator 100 is held sideways (so the smoothing rod 116 may be effectively used), but rather is dispensed by the user causing the movable wall 204 to be moved. As a result, depending on the substance the applicator is being used with, the slot may be of a width to prevent dispensation of the fluid without the user causing the endwall 204 to move. In an alternative embodiment, the slot is equipped with a structure (not shown) for varying the width of the slot so that different fluids can be accommodated within the same applicator 100 for different applications. The dispensing end 106 is preferably removable to allow the user to fill the applicator 100 with the desired fluid.
In another alternative embodiment, shown in FIGS. 5 and 6, a telescoping rattail comb 500 is formed from the rattail 113 and comb 112 . In this embodiment, because it is detached, the telescoping rattail comb 500 is provided separately from the applicator 100 . The telescoping comb 500 may be far more versatile than if it is simply attached to the applicator 100 . For example, a hairdresser may use the comb separately to part hair, comb the hair into place using the comb 112 , and then use the applicator 100 to apply a fluid to the hair. The comb 500 may also be compactly stored and is easier to clean than if left attached to the applicator 100 .
In one embodiment of the telescoping rattail comb 500 , illustrated in FIG. 6, the telescoping portion includes a proximal end 602 and a distal end 604 , and the comb portion 112 includes a comb attached to a substantially hollow cylinder 606 , and the telescoping rattail comb 500 further includes a detachable plug 608 located at the distal end 604 for retaining the telescoping portion 113 within the substantially hollow cylinder 606 .
In yet another alternative embodiment of the present invention, illustrated in FIG. 7, the body 102 is shaped like a teardrop along the vertical. In this way, the applicator 100 will fit ergonomically within the user's hand, thereby avoiding undue stress or strain to the user and preventing cramping of the user's hand. In particular, the larger curved portion of the sidewalls 102 can be placed closest to the user's palm, while the tapered portion of the sidewalls 102 can be grasped between the user's fingers. In this way, the user can have more control over the applicator 100 than with, for example, an ovular shape. The teardrop shape can also be utilized to provide the user improved visibility to the comb 112 , smoothing rod 116 , or other structure included along the apex of the teardrop. Improved visibility makes it easier for the user to achieve a better result when using the comb 112 , smoothing rod 116 , or other structure located at the apex. The teardrop shape can be applied to the entire body 102 , or a portion of the body approximately the width of the user's hand. The benefits of the teardrop shape can realized even if it is applied only to the area approximately the width of the user's hand.
In another alternative embodiment, illustrated in FIG. 8, the applicator 100 is equipped with multiple slots, 800 a , 800 b and 800 c . By providing multiple slots, the applicator 100 can be used with more controlled and longer strokes, while avoiding waste. In particular, when the dispensing end 106 is convexly shaped, the single slot 800 c can be placed at the tallest point of the dispensing end 106 . When a fluid is forced toward the slots 800 a-i c , the fluid will tend to take a path of least resistance, thereby tending initially toward slot 800 c , with only a smaller portion coming out of slots 800 b and slots 800 a . As slot 800 c lets fluid out, a backup will be created (relative to the time period before no fluid was exiting slot 800 c ) and fluid will move toward slots 800 a-b with greater force. As a result, the fluid will “back-up,” or move to exit slots 800 a-b as well. Because slots illustrated in FIG. 8 cover an overall smaller surface area as they move away from the pinnacle of the convexly shapped dispensing end 106 , they will let lesser amounts of fluid from them as they get further from the pinnacle. In this way, a user can provide more fluid at one time and without the problems of messiness or unnecessary waste provided if the slots were uniform in coverage, a longer, more controlled stroke is possible. As with other embodiments, the dispensing end 106 may be utilizes with a press-fit, screw-on cap, or through other suitable means.
FIGS. 9 and 10 provide alternative embodiments having multiple apertures or cavities for dispensing a fluid. In these Figures, the apertures 902 are provided along the width of the lip 112 and brush or comb bristles 302 .
While particular embodiments of the invention have been shown, it will be understood, of course, that the invention is not limited thereto since modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. For example, although a preferred use of the applicator 100 is to apply relaxer to hair, the applicator 100 may also be used for dispensing other substances, for example gel, leave-in conditioner, hair color or bleach to the hair. Additionally, an alternative embodiment includes the elongated slot 110 as a slot in the sidewall 102 , adjacent the dispensing end 106 of the applicator. It is, therefore, contemplated by the appended claims to cover any such modifications as incorporate those features which constitute the essential features of these improvements within the true spirit and the scope of the invention.
|
An apparatus for applying a fluid to hair is provided. The apparatus includes a reservoir for containing a fluid, sidewalls for defining the reservoir. The sidewalls form an elongate curvilinear cavity along an interior surface and forming an exterior surface, wherein the cavity includes the reservoir and having a top portion and a bottom portion and the cavity having a longitudinal axis. The applicator also includes a top endwall located at the top portion of the sidewalls and the endwall includes an elongate cavity for dispensing a fluid. A flexible lip is located adjacent the cavity for assistance in dispensing a fluid from the elongate cavity is also included in the applicator. The applicator includes a movable bottom endwall for containing the fluid within the reservoir and advancing fluid and a rotatable smoothing rod attached to the exterior surface of the sidewalls.
| 0
|
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. patent application Ser. No. 13/749,448 entitled “System and Method for Secure SMI Memory Services” which was filed on Jan. 24, 2013 and is incorporated herein by reference in its entirety for all purposes.
TECHNICAL FIELD
[0002] The present disclosure relates generally to computing systems and information handling systems, and, more particularly, to a system and method for providing secure system management interrupt (SMI) memory services in a computing system or information handling system.
BACKGROUND
[0003] As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to these users is an information handling system. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may vary with respect to the type of information handled; the methods for handling the information; the methods for processing, storing or communicating the information; the amount of information processed, stored, or communicated; and the speed and efficiency with which the information is processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include or comprise a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
[0004] An information handling system will typically include some type of temporary information storage medium, such as random access memory (RAM) or system management RAM (SMRAM). The amount of memory included in an information handling system may be on the order of gigabytes. As memory size increases, the likelihood that part of the memory will either be manufactured defective or become defective over time increases. If left unmanaged, the presence of defective memory cells, regardless of their size, can cause the information handling system to fail. Such failure can initiate an abrupt end to the current operation of the information handling system, resulting in the loss of critical data. A memory failure could also prevent the information handling system from starting up altogether.
[0005] As information handling systems continue to evolve and computer technology advances, the operational relationship between the CPU and memory becomes more significant and complex. Many attributes of modern systems (specifically, the introduction of multi-core processors and virtualization) are contributing to an ever-larger memory footprint within a typical information handling system. Consequently, not only is system memory becoming a much more substantial percentage of the overall cost of the information handling solution, the impact of erroneous behavior in the memory can have a much more adverse effect on the life cycle expense associated with the information handling system.
[0006] Information handling systems also continue to evolve and computer technology continues to advance to provide for efficient management of energy consumption. Many information handling systems and computer systems include a system management mode (SMM) that allows energy conservation to be built into the system. SMM can initiate a sleep mode or energy conservation mode during periods of processing inactivity that can include turning off of peripheral devices, parts of the system, the entire system, etc. During these periods of inactivity, the information handling or computer system's status is maintained in SMRAM which is a secure area of memory.
SUMMARY
[0007] In accordance with the present disclosure, a system and method are herein disclosed for providing secure SMI memory services. The system and method described herein involve the management of the memory resources of an information handling system. The system and method involve securing SMI memory services.
[0008] In an information handling system, system memory is vulnerable to destructive attacks by vicious predators such as rootkit attacks and other destructive programs.
[0009] The system and method disclosed herein are technically advantageous because a mechanism is provided for eliminating the risks of system memory attacks and compromises to data storage posed by such attacks. In particular, the present disclosure provides a way for an information handling system to provide secure SMI memory services (SSMS) in SMI that allows any SMI driver to allocate memory for use while processing SMI, with the guarantee that the contents of the memory will be overwritten before exiting SMI. This overwriting obviates the need for each SMI driver to implement methods for ensuring that sensitive temporary data is expunged before exiting SMI. By effectively protecting system memory from vicious attacks that could destroy or compromise sensitive temporary data, data integrity is preserved. For example, the present invention prevents information leakage. Overall system costs for the information handling system are correspondingly reduced as destructive attacks that allow sensitive information to be accessed surreptitiously by another system or program are prevented. Other technical advantages will be apparent to those of ordinary skill in the art in view of the following specification, claims, and drawings.
[0010] According to a specific example embodiment of this disclosure, an information handling system may comprise a method for providing secure SMI memory services, said method comprising the steps of; requesting one or more actions, triggering an SMI interrupt, entering SMM, initiating an SMI driver associated with the SMI interrupt, initiating one or more SMI handlers registered to the SMI driver associated with the triggered SMI interrupt, requesting for each of the SMI handlers an allocation of one or more blocks of memory from a secure SMI memory services driver, wherein the one or more blocks of memory is requested from a memory pool associated with SMM memory, and performing one or more actions by the SMI handler, wherein the SMI handler uses one or more of the allocated blocks of memory; and performing a secure erase of each block of memory by the secure SMI memory services driver after performing the one or more actions. In another embodiment, the one or more actions includes at least one of a request to perform a password validation, alter system setup variables, perform thermal management and perform power management. In yet another embodiment, the method comprises validating a password against a system password before performing the one or more actions and the method may further comprise hashing or transposing the password prior to validating the password.
[0011] In another example embodiment, the method further comprises performing a secure erase of the one or more blocks of memory prior to performing the one or more actions by the SMI handler and another embodiment further comprises deallocating the one or more blocks of memory prior to exiting the SMM and in another embodiment the method further comprises performing SMM exit tasks and performing secure SMI memory services exit tasks.
[0012] According to another example embodiment of this disclosure, an information handling system for securing SMI memory services comprising, a main memory; a system management mode, wherein SMM memory is part of the main memory, a memory pool, wherein the memory pool is reserved memory within SMM memory and includes one or more blocks of memory, a system management interrupt (SMI) driver, wherein the SMI driver is initiated by triggering an SMI interrupt and wherein the one or more blocks of memory is communicatively coupled to one or more SMI handlers associated with the SMI driver, and a secure SMI memory services (SSMS) driver wherein the SMI driver is communicatively coupled to the one or more SMI handlers and the block of memory, wherein the SSMS driver allocates the block of memory upon a request from the one or more SMI handler, wherein the one or more SMI handlers uses the allocated block of memory to perform one or more actions, and wherein the SSMS driver performs a secure erase of the block of memory upon completion of the one or more actions by the SMI driver. In another embodiment, the block of memory is system management RAM. In yet another embodiment the SMI driver initiates the SSMS driver to deallocate the block of memory upon completion of the one or more actions by the SMI driver.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] A more complete understanding of the present embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein:
[0014] FIG. 1 is a block diagram of an information handling system;
[0015] FIG. 2 is a block diagram of modes of an information handling system;
[0016] FIG. 3 is a block diagram of main memory, including system management RAM (SMRAM);
[0017] FIG. 4 is a flow diagram for performing a secure SMI memory services action; and
[0018] FIG. 5 is a flow diagram for performing password verification of a secure SMI memory services action.
[0019] While the present disclosure is susceptible to various modifications and alternative forms, specific example embodiments thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific example embodiments is not intended to limit the disclosure to the particular forms disclosed herein, but on the contrary, this disclosure is to cover all modifications and equivalents as defined by the appended claims.
DETAILED DESCRIPTION
[0020] For purposes of this disclosure, an information handling system may include any instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, an information handling system may be a personal computer, a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system may include random access memory (RAM), system management RAM (SMRAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components of the information handling system may include a storage management initiative standard interface (SMI), one or more disk drives, one or more network ports for communication with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, and a video display. The information handling system may also include one or more buses operable to transmit communications between the various hardware components.
[0021] Referring now to the drawings, the details of specific example embodiments are schematically illustrated. Like elements in the drawings will be represented by like numbers, and similar elements will be represented by like numbers with a different lower case letter suffix.
[0022] Referring to FIG. 1 , depicted is a block diagram of an example information handling system having electronic components. Generally, these electronic components are mounted on at least one printed circuit board (PCB) (motherboard) and communicate data and control signals over signal buses. In one example embodiment, the information handling system is a computer system. The computer system may be, for example, configured as a server or any other computer system configuration. The information handling system, generally referenced by the numeral 100 , comprises at least one processor or CPU 110 communicatively coupled to a host bus(es) 120 . While only one CPU 110 is depicted, it should be understood that any number of CPUs may be present in the information handling system according to the specific needs, operation, function, requirements and use of the information handling system and that these CPUs operate and function similarly to CPU 110 . CPU 110 may include hardware and software components for the structure and operation of the process steps and system disclosed. While not specifically shown, it should be understood that any number of program modules comprising computer-readable instructions may be stored in the information handling systems memory and may be executed by CPU 110 . This memory may be a hard disk, magnetic disk, optical disk, ROM, RAM or any other computer media known to one of ordinary skill in the art for the storage and retrieval of data, including executable or computer-readable instructions. Upon execution of the computer-readable instructions, certain actions may be performed as described in this disclosure. A memory controller (hub) or north bridge 140 is communicatively coupled to the CPU 110 via the host bus(es) 120 . The north bridge 140 is generally considered an application specific chip set that provides connectivity to various buses, and integrates other system functions such as a memory interface. The chip set may also be packaged as an application specific integrated circuit (ASIC). The north bridge 140 typically includes functionality to couple the main system memory 150 to other devices within the information handling system 100 . Thus, memory controller functions, such as main memory control functions, typically reside in the north bridge 140 . Main memory 150 may also include system management mode (SMM) memory 152 . In addition the north bridge 140 provides bus control to handle transfers between the host bus(es) 120 and a second bus(es), e.g., PCI bus 160 , AGP bus 170 coupled to a video graphics interface 172 which can drive a video display (not shown). The north bridge 140 is coupled to the south bridge 130 via bus(es) 160 . A third bus(es) 162 may also comprise other industry standard buses or proprietary buses, e.g., ISA, SCSI, II 2 C, SPI, USB, low pin count (LPC) buses through a south bridge(s) (bus interface) 130 . A disk controller 166 and input/output interface(s) 164 may be coupled to the third bus(es) 162 . At least one of the input/output interfaces(s) 164 may be used in combination with a baseboard management controller, serial port and/or Ethernet network interface card (NIC). The south bridge 130 may generate an SMI interrupt on bus(es) 132 which is coupled to the CPU 110 . The SMI interrupt may be triggered by a hardware event, for example, a thermal management event or a power management event, at input/output interfaces 164 . The SMI interrupt may also be triggered from a software event generated at the CPU 110 that when received by the South Bridge initiates an SMI interrupt, for example, the software event may be a request to validate a password or to change a setup variable.
[0023] Referring to FIG. 2 , depicted generally at 200 is a flow diagram of possible modes of an information handling system. Possible modes include real-address mode 210 , protected mode 220 , virtual 8086 mode 230 , and system management mode (SMM). SMM 240 is entered by asserting either a hardware interrupt or a software interrupt called a system management interrupt (SMI) 232 a - c from any other mode. Once SMM is entered, the operating system is placed in a frozen state for the duration of the mode. SMM is exited by issuing a resume operation instruction (“rsm”) 234 a - c . Exiting SMM unfreezes or restores the operating system to the identical state that existed prior to entering SMM (except for any modifications, for example modifications to system variables, specifically made during SMM). Exiting virtual 8086 mode 230 may also cause a reset 222 of variables when returning to real-address mode 210 .
[0024] Referring to FIG. 3 , depicted generally at 300 is a block diagram of main memory 150 of an information handling system 100 . More specifically, depicted is a more detailed block diagram of SMM memory 152 . Main memory 150 may be RAM or any other type of memory known to one of ordinary skill in the art. Main memory 150 may have a defined address space of memory called SMM memory 152 for use during an SMI interrupt. SMM memory 152 may be SMRAM or any other type of memory known to one of ordinary skill in the art. Upon the triggering of an SMI interrupt(s) 132 , variables associated with the CPU 110 are saved in an address space State Save 314 of SMM memory 152 and SMM is entered. SMM may store the complete CPU 110 state information or only partial CPU 110 state information. Execution of the program associated with the SMI interrupt(s) 132 begins according to the SMI Driver(s) 310 a - n . Multiple SMI Driver(s) 310 a-n may be associated with an SMI interrupt(s) 132 . Multiple SMI interrupts 132 may also be asserted. SMM allocates memory from a reserved pool of memory, Secure SMI Services Memory Pool 316 . The Secure SMI Services Memory Pool 316 may include multiple allocated blocks of memory 312 a - n . Allocated Block(s) of Memory 312 a - n are used by the SMI Driver(s) 310 a - n to store variables used during execution of the program associated with the SMI interrupt(s) 132 . Upon exiting SMM, allocated Block(s) of Memory 312 a - n may be erased and returned to the Secure SMI Services Memory Pool 316 . Also, the CPU 110 state variables stored in State Save 314 may be restored.
[0025] Referring to FIG. 4 , depicted generally at 400 is a flow diagram for performing secure SMI services according to one example embodiment of the present disclosure. In step 402 a request is received to perform a requested action by South Bridge 130 . This request may be generated, for example, by software executing a instructions at CPU 110 . This request may also be generated, for example, by hardware 164 . The requested action may include thermal management, power management, change/alter system variables, or any other action known to one of ordinary skill in the art. An SMI interrupt is generated at step 404 that corresponds to the requested action. The requested action may correspond to one or more SMI interrupts and more than one action may be requested. At step 406 , the SMM is entered. Next, at step 410 , SMM entry tasks are performed. SMM entry tasks may include saving certain CPU state information. Step 420 initiates the SMI handler registered for the SMI driver associated with the corresponding SMI interrupt. Each SMI interrupt has a corresponding SMI handler. One or more SMI drivers may be associated with the SMI handler for a given SMI interrupt. More than one SMI interrupt may be received for processing while in SMM. At Step 430 , the SMI handler initiates the Secure SMI Memory Services Driver (which may include one or more drivers for a given SMI handler associated with an SMI interrupt) for the corresponding SMI interrupt. The Secure SMI Memory Services are represented at 412 . The Secure SMI Memory Services Driver (or SSMS driver) associated with the SMI handler allocates a block of SMM memory from memory pool 316 at Step 432 . The allocated block of SMM memory may include multiple blocks of allocated memory as shown in FIG. 3 as 312 a - n . The allocated blocks of memory 312 a - n may be allocated according to a predetermine size, for example, 8 Mb, 16 Mb, 32 Mb, etc. Also, allocated blocks of memory 312 a - n may be allocated according to specific requirements of the SMI driver and SMI handler and may each be of varying and different sizes. For example, 312 a may be allocated as a 16 Mb block of memory while 312 b may be allocated as a 32 Mb block of memory. Step 434 determines if the allocated memory at step 432 should be erased prior to performing the requested action. If the allocated memory should be erased, then at step 436 the Secure SMI Memory Services performs a secure erase of the allocated block of memory. Step 438 determines if more memory should be allocated. If so, then the process returns to Step 430 . Steps 430 , 432 , 434 , 436 and 438 may be repeated until all requested memory blocks have been allocated.
[0026] Once the memory blocks required by the SMI handler have been allocated, the SMI handler completes SMI processing at Step 440 . The SMI processing completed at Step 440 may include any steps necessary to perform the requested action received at Step 402 . For example, FIG. 5 at 500 depicts steps necessary to perform password validation prior to performing the requested action at Step 530 . At step 510 the administrative password, which may be a user-entered password or a previously stored password, is verified against the system password, which may be stored in non-volatile memory. Step 520 determines if the passwords match. If the passwords match, then at Step 530 the requested action is performed. The requested action may be an action to alter certain system variables. The requested action may also be to perform certain processes or steps associated with power management or thermal management. If the passwords do not match, then the requested action is not performed and the allocated memory block(s) is erased and the memory block is freed. The allocated memory block(s) may now be free memory of the Secure SMI Services Memory Pool 316 .
[0027] Returning to FIG. 4 , once the SMI handler has completed all SMI processing, Step 450 determines if any memory needs to be deallocated. If memory does need to be deallocated, then at Step 452 , the Secure SMI Memory Services erases and deallocates the allocated block(s) of SMM memory. Next, Step 454 determines if any pending SMI interrupts still need to be serviced. Control returns to Step 420 if there are any pending SMI interrupts. The above steps are repeated until all pending SMI interrupts have been serviced. Once all pending SMI interrupts have been serviced, then Step 460 performs any initial SMM exit tasks. Following completion of the SMM exit tasks, then Step 470 performs the Secure SMI Memory Services SMI exit routine(s). At Step 472 , the Secure SMI Memory Services erases and deallocates all allocated blocks of memory during the SMI. Next, Step 480 performs any final SMM exit tasks. At Step 490 , an RSM instruction is issued to exit SMM. SMM is exited, Step 492 , and the information handling system 100 returns to the previous mode. The information handling system may also return to any other mode associated with the information handling system, examples of which have been depicted in FIG. 2 .
[0028] Although this disclosure has been described with respect to the operation of SMI within an information handling system, it should be recognized that the Secure SMI Memory Services described herein may be implemented with any information handling system. Consistent with this disclosure, for example, an information handling system may comprise one or more of a server, workstation, desktop computer, laptop computer, or any other computer system known to one of ordinary skill in the art.
[0029] The concepts disclosed herein should not be understood to be limited to the exemplary embodiments described, but should be understood to encompass all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Moreover, although this disclosure describes and illustrates respective embodiments herein as including particular components, elements, functions, operations, or steps, any of these embodiments may include any combination or permutation of any of the components, elements, functions, operations, or steps described or illustrated anywhere herein that a person having ordinary skill in the art would comprehend.
|
In accordance with the present disclosure, a system and method are herein disclosed for providing secure SMI memory services, including the protection of SMM memory from surreptitious attacks by, for example, rootkits. Information handling systems are susceptible to attacks, especially attacks on SMM memory. In one example, an SMI handler corresponding to the SMI Driver associated with an SMI interrupt performs validation of a password. An SSMS driver allocates memory for the SMI handler to use with the validation process and also performs a secure erase of allocated memory blocks upon completion of all secure SMI Memory Services. By controlling the validation and secure erase process through the use of the SMI handler and SSMS driver, information leakage can be prevented resulting in system data integrity.
| 8
|
PRIORITY
The present application is a divisional of, and claims priority from, co-pending U.S. application Ser. No. 10/727,807 filed Dec. 4, 2003, entitled “METHOD AND DATA STRUCTURE FOR TRACKING SWITCH TRANSACTIONS IN A COMMUNICATIONS-NETWORKING ENVIRONMENT.”
INTRODUCTION
A telecommunications network is composed of a variety of components. In addition to routers, signal-control points, and hubs, switches are ubiquitous components found in almost all communications networks. Switches process configuration transactions. Transactions can perform a variety of tasks. A transaction may be as simple as an entry or update in a database or as complex as processing a set of sequences that perform an ultimate task. As is appreciated in the art, a typical task for a transaction to complete is to add, delete, or otherwise modify data in a switch table.
Two types of data are common in a telecommunications-network environment: business data and administrative or transaction data. As used herein, business data refers to longer-term data that describes physical aspects of a network. Exemplary business data includes NPA-NXX codes, switch identifiers, trunk identifiers, trunk-group identifiers, station ranges, point of presence identifiers, network-element addresses, component locations, and the like. Transaction data is short-term data substantially limited to the lifespan of a transaction. Exemplary transaction data includes data such as a transaction ID, a time stamp, a status identifier, request information, a requestor' s name, etc. Historically, business data has been stored in the same tables as transaction data. Although such a scheme may have been adequate for simple communications networks, it is an inefficient data model that suffers from several disadvantages that are exemplified in a complex communications network.
A first problem associated with storing business data and transaction data in a common table is data duplication. That is, data is unnecessarily repeated across many tables. For instance, a first table may store a transaction ID, a time stamp, and a first parameter. For certain business reasons, a second table may store the same transaction ID and maybe even a time stamp, but a second parameter. Historically, data has been stored in different databases to suit the needs of a communications carrier. For example, data associated with communications feeds has been maintained separately from business data, which has in turn been maintained separately from switch data. To the extent a table stores business data along with transaction data, then as the transaction data changes, the table or tables must also be updated, which leads to a second problem with storing business data with transaction data: updating tables is difficult.
If a first table having transaction data needs to be updated, then so too do all tables that share that common transaction data. Thus, either a user or application would need to update several tables associated with only a single change. Moreover, updating tables that share transaction data with business data is difficult because the data types of the various tables may be different. For example, a transaction ID field of a first table may be formatted to receive numerical input only. But a transaction ID field of a second table may be configured to accept data as a text string. Thus, to update both tables with a new transaction ID, the data would first need to be formatted as a number and then formatted as a text string. In other situations, data masks may be applied in some tables but not in other tables. In still other situations, a data field of a first table may accept data having a certain number of digits, while a sister table may accept data associated with the same field but require a different number of digits. Thus, having to reconcile multiple formats for the same data file types was a laborious and time-intensive task.
A third problem associated with grouping transactional data with business data relates to fault recovery. Historically, recovering from an error transaction has been complicated by a lack of information available. In order to recover from an error transaction, one needs to know where the transaction failed so that it can be started up again at that point. However, determining where a transaction failed using methods available in the prior art has not allowed analysts to precisely determine where a transaction has failed, which highlights a fourth shortcoming of the prior art. The prior art does not offer the ability to establish an audit trail associated with a transaction's progress.
Traditionally, old status data has been overwritten with new status data. Overriding status data deprives an analyst of visibility as to prior happenings within the switch. The lack of ability to establish an audit trail removes the ability for a user to identify at what point during a transaction's progression the transaction failed. Moreover, without an audit trail, no metrics associated with transaction-processing characteristics can be gleaned; this makes inefficiencies difficult if not impossible to identify and prohibits benchmarking for users. That is, no evaluation can be made at a user level.
The prior art could be improved by providing a system and method for maintaining a record of transaction data related to but separate from business data in a telecommunications-networking environment.
SUMMARY OF THE INVENTION
The present invention solved at least the above problems by providing a system, method, and data structure for separating transaction-dependent data from transaction-independent data. In one embodiment, the present invention separates transaction data from its corresponding source, or business data. The present invention has several practical applications in the technical arts including reducing or eliminating data duplication. As a transaction progresses, only data associated with the transaction progression needs to be provided, but not business data associated with the transaction.
Moreover, the present invention greatly simplifies updating a transaction's status. More than just updating a transaction status, the present invention allows greater detail associated with the status of a transaction's progress to be provided. No longer is there a need to update several tables or to format data differently for different fields that store a common data item. Also, the present invention enhances troubleshooting. By establishing an audit trail, the present invention does not overwrite old data with new data.
Rather, the present invention maintains a historical log associated with a transaction's progression. This allows metrics about transaction-processing characteristics to be gained. With these metrics, users can establish benchmarking for evaluation purposes and to identify users that need to be trained. The present invention allows rapid identification of transaction inefficiencies by creating an audit trail. Thus, the present invention can rapidly identify faults by monitoring the progression of a transaction through a communications network and logging data associated with the progress of the transaction in one or more memories that store data distinct from business data.
In a first aspect, computer-readable media having computer-useable instructions for tracking the progression of a switch transaction is provided. The method includes creating an audit trail associated with the switch-transaction progression, iteratively updating the audit trail incident to an occurrence of designated transaction-processing substeps without overwriting previously stored data, and processing the audit trail so that it is available for access by a user interface.
In a second aspect, a machine-implemented method is provided for facilitating telecommunications-network configuration-transaction processing. The method includes maintaining a first table that stores transaction-independent data and a second table that stores transaction-dependent data. The tables are linked by a transaction identifier so that without user intervention, the second table (but not the first table) is iteratively updating incident to the occurrence of certain predestined substeps of the configuration transaction.
In a third aspect, a memory is provided for storing data associated with creating a transaction-audit trail for access by an application program being executed on a computing device. The present invention includes both information used by application programs and information regarding physical interrelationships within a memory. The memory includes a first data structure stored that includes a transaction-progression table that tracks transaction statuses respectively associated with completing a plurality of subtransaction steps. The memory also includes a set of computer-useable instructions that prevent subsequent transaction statuses from overwriting previous transaction statuses.
In a fourth aspect, the present invention includes computer-readable media having stored thereon a data structure for monitoring the progression of a telecommunications switch transaction. The data structure includes a first table that stores a transaction-request identifier, a first set of data that does not change as the switch transaction progresses toward completion, and no data that does change as the switch transaction progresses toward completion. A second table is logically associated with the first table and is iteratively updated as the switch transaction progresses toward completion. The second table stores the transaction-request identifier and a second set of data that do changes as the switch transaction progresses toward completion. The data that does change can be limited to the lifespan of a configuration-transaction request and includes an indication of the request's status at some point in time or interval.
In a final exemplary aspect, the present invention includes a method for increasing the efficiency of a communications network by storing business data in a table separate from transaction data.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The present invention is described in detail below with reference to the attached drawing figures, wherein:
FIG. 1 depicts an exemplary operating environment suitable for practicing an embodiment of the present invention;
FIGS. 2 and 3 are block diagrams that depict several inefficiencies of a data model that stores transaction data with business data in the same table and across multiple tables;
FIG. 4 is an exemplary data model according to an embodiment of the present invention that stores business data separate from transaction data; and
FIG. 5 is an exemplary flow diagram that illustrates a method for facilitating telecommunications network configuration transaction processing, according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a method and data model that enables an audit trail to be maintained of configuration transaction requests as they progress through a communications network. The present invention will be better understood from the detailed description provided below and from the accompanying drawings of various embodiments of the invention. The detailed description and drawings, however, should not be read to limit the invention to the specific embodiments. Rather, these specifics are provided for explanatory purposes that help the invention to be better understood.
Specific hardware devices, programming languages, components, processes, and numerous details including operating environments and the like are set forth to provide a thorough understanding of the present invention. In other instances, structures, devices, and processes are shown in block-diagram form, rather than in detail, to avoid obscuring the present invention. But an ordinary-skilled artisan would understand that the present invention may be practiced without these specific details. Computer systems, servers, work stations, and other machines may be connected to one another across a communication medium including, for example, a network or networks.
Throughout the description of the present invention, several acronyms and shorthand notations are used to aid the understanding of certain concepts pertaining to the associated system and services. These acronyms and shorthand notations are solely intended for the purpose of providing an easy methodology of communicating the ideas expressed herein and are in no way meant to limit the scope of the present invention. The following is a list of these acronyms:
AT
Access Tandem
CLLI
Common Language Location Identification
EO
End Office
NPA
Numbering Plan Area (Area Code)
NXX
Prefix - first three digits of telephone number after NPA
POP
Point Of Presence
POP CLLI
CLLI that identifies a point of presence
Further, various technical terms are used throughout this description. A definition of such terms can be found in Newton's Telecom Dictionary by H. Newton, 19th Edition (2003). These definitions are intended to provide a clearer understanding of the ideas disclosed herein but are in no way intended to limit the scope of the present invention. The definitions and terms should be interpreted broadly and liberally to the extent allowed by the meaning of the words offered in the above-cited reference.
As one skilled in the art will appreciate, the present invention may be embodied as, among other things: a method, system, or computer-program product. Accordingly, the present invention may take the form of a hardware embodiment, a software embodiment, or an embodiment combining software and hardware. In a preferred embodiment, the present invention takes the form of a computer-program product that includes computer-useable instructions embodied on one or more computer-readable media.
Computer-readable media, which are non-transitory, include both volatile and nonvolatile media, removable and nonremovable media, and contemplates media readable by a database, a switch, and various other network devices. Network switches, routers, and related components are conventional in nature, as are means of communicating with the same. By way of example, and not limitation, computer-readable media comprise computer-storage media and communications media.
Computer-storage media, or machine-readable media, include media implemented in any method or technology for storing information. Examples of stored information include computer-useable instructions, data structures, program modules, and other data representations. Computer-storage media include, but are not limited to RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile discs (DVD), holographic media or other optical disc storage, magnetic cassettes, magnetic tape, magnetic disk storage, and other magnetic storage devices. These memory components can store data momentarily, temporarily, or permanently.
Communications media typically store computer-useable instructions—including data structures and program modules—in a modulated data signal. The term “modulated data signal” refers to a propagated signal that has one or more of its characteristics set or changed to encode information in the signal. An exemplary modulated data signal includes a carrier wave or other transport mechanism. Communications media include any information-delivery media. By way of example but not limitation, communications media include wired media, such as a wired network or direct-wired connection, and wireless media such as acoustic, infrared, radio, microwave, spread-spectrum, and other wireless media technologies. Combinations of the above are included within the scope of computer-readable media.
To help explain the invention without obscuring its functionality, a preferred embodiment will now be referenced in connection with a telecommunications network. FIG. 1 indicates an exemplary operating environment suitable for practicing the present invention and is referenced generally by the numeral 100 . Operating environment 100 should not be construed as a limitation of the present invention. Additional components that can be used in connection with the present invention are not shown so as to not obscure the present invention.
Exemplary operating environment 100 includes a request-audit table 110 and a transaction-processing system 112 . Transaction-processing 112 includes a request server 114 , a business server 116 , a network server 118 , and a communications server 120 . Transaction-processing system 112 is shown in block-diagram form with only a few exemplary components so as to not obscure the present invention. Those skilled in the art will appreciate that a transaction-processing system may include a litany of other components, which are contemplated within the scope of the present invention but not shown. Transaction-processing system 112 is coupled to one or more communications switches 122 .
The servers illustratively shown as components of transaction-processing system 112 may be known by other names but illustrate that a transaction request (“request”) 124 progresses through a processing system. Thus, the present invention should not be construed as a method or system limited to a request that progresses through the illustrative servers shown. Rather, FIG. 1 illustrates that a request 124 progresses through several transitional states toward completion.
In the simplified environment shown, request 124 is received by request server 114 . At a step 126 , one or more entries are made into request-audit table 110 , which will be explained in greater detail below. The table entries describe aspects of a transaction request related to its progression through a network. Exemplary entries include an indication that request 124 was received by request server 114 , that request server 114 is processing request 124 , that request server 114 has completed processing its portion of functionality associated with request 124 , or any other indication of a subprocessing step. Processing continues to business server 116 .
At a step 128 , request-audit table 110 is updated to reflect the progression of transaction request 124 . The updates of step 128 may include an indication that the transaction request has been received, is being processed, or has been completed by business server 116 . Processing continues onto network server 118 , which performs actions on request 124 and updates request-audit table 110 at a step 130 . In a final exemplary process, request 124 is sent to communications server 120 . At a step 132 , the different statuses associated with communication server 120 are updated in request-audit table 110 . When transaction request 124 is sent to one or more communications switches 122 , an entry can be made in a single table, such as request-audit table 110 , that the transaction has been processed and sent to the network. By updating only a single table, the method described with reference to FIG. 1 allows an audit trail to be developed, whereby problems that occur during the progression of request 124 can be more easily identified.
To further illustrate a portion of the benefits associated with the present invention, FIGS. 2 and 3 depict a set of tables that include both business data and transaction data. As used herein, “business data” refers to transaction-independent data (except for a transaction identifier) and “transaction data” refers to transaction-dependent data, or data that does not vary as a transaction processes through various components toward completion. Turning now to FIG. 2 , three instances of an NPA table are shown and referenced by numerals 210 , 212 , and 214 . The NPA table relates NPA data with transaction data. NPA table 210 includes four columns— 216 , 218 , 220 , and 222 —that respectively correspond to an NPA ID, an NPA type, a transaction ID, and a transaction-status identifier (transaction status). A single row 224 is shown that reflects an NPA ID of “913,” an NPA type of “domestic,” a transaction ID of “T1234,” and a transaction status of “request received at requestor.” These fields are respectively shown by reference numerals 226 , 228 , 230 , and 232 . As can be seen, business data 234 is undesirably housed in table 224 along with transaction data 236 . Historically, when the status of a transaction's progression changed, old data was overwritten with new data.
Absent the present invention, when a transaction's status changed, the new status was merely updated from a previous status. Stored in a single field, the status identifier would be perpetually overwritten by new updates. In a specific, arbitrary example, after a request had been received from the requestor and the request progressed to being processed by business data, the transaction status of “request received at requestor” reflected in cell 232 would be replaced with a transaction status of “processing business data” as reflected in cell 232 A, which is the same cell as cell 232 but numerically distinguished for explanatory purposes.
Thus, table 212 reflects an updated transaction status that has overwritten a previous status identifier. Table 212 is the same table as table 210 but is denoted by a unique reference numeral to explain the present invention. To further illustrate at least one problem historically associated with storing business data 234 in the same table as transaction data 236 , table 214 reflects that a transaction status of “building switch command” in cell 232 B has overwritten the previous status identifier of “processing business data,” reflected in cell 232 A.
As can be seen by the simplified illustration of FIG. 2 , there is no way to retrieve any type of historical data or audit trail associated with the progression of a transaction request. Without an audit trail, no metrics can be gleaned and no performance benchmarks. Thus, if a user wished to track the time lapse between when a transaction request was received to when the processing of business data began, such data would not be available to a user.
Another problem associated with grouping business data with transaction data in the same table is that updating transaction-processing statuses involves updating multiple tables. This is because data must be unnecessarily duplicated across multiple tables. An example of these inefficiencies can be illustrated with reference to FIG. 3 .
Turning now to FIG. 3 , three instances of the same table are shown and referenced respectively by numerals 310 , 312 , and 314 . Table 310 includes a customer-identifier column 316 , a customer-data column 318 , a transaction-ID column 320 , and a transaction-status column 322 . Table 310 includes one row 324 having four cells referenced by numerals 326 , 328 , 330 , and 332 . Here, business data 334 (which includes customer ID 316 and customer data 318 ) is inefficiently stored in the same table as transaction data 336 (which includes transaction ID 320 and transaction status 322 ). Table 310 observed in connection with table 210 of FIG. 2 illustrates that the transaction ID and transaction status records are duplicated in two tables.
The transaction ID of “T1234” is stored both in cell 230 of table 210 and in cell 330 of table 310 . Similarly, the transaction-status identifier is stored both in cell 232 of table 210 and in cell 332 of table 310 . When the status of a transaction request changes, both tables must be updated. For example, when the transaction request's status transitions from “request received at requestor” to “processing business data,” then both tables 210 and 310 must be updated. Updating table 310 has historically been done by overwriting the data in cell 332 with new data, such as “processing business data” as reflected in cell 332 A, which is the same cell as cell 332 but referenced here with a unique numeral to ease description of the present invention.
When the transaction status changes to “building switch command,” tables 212 and 312 must both be updated as respectively reflected in tables 214 and 314 . The present invention provides a data structure whereby transaction data is stored separately from business data.
Turning now to FIG. 4 , an exemplary data model according to an embodiment of the present invention is shown with reference to two illustrative tables 410 and 412 that store business data while a third table 414 stores transaction data. A transaction identifier is included in table 410 , linking it to the transaction data of table 412 . Those skilled in the art would appreciate that additional transaction data is stored in tables 210 and 310 , but only the “transaction status” column was provided for clarity purposes. Table 410 now has no need to store all of such transaction data. Similarly, table 412 is a customer table that associates business data of a customer ID and other customer data with a single identifier, namely a transaction identifier, such as “transaction ID.”
The transaction-ID field of tables 410 and 412 is linked to a request-audit table 414 by a single field, the transaction ID field. The request-audit table includes a transaction-ID column 416 , a transaction-status column 418 , and a time-stamp column 420 . Request-audit table 414 includes a first row 422 , a second row 424 , a third row 426 , and a fourth row 428 . Each of these rows corresponds to a desired logable event and should not be construed as a limitation of the present invention. Any event that is desirous to log can be logged and tracked.
Rows 422 through 428 are exemplary rows that may, for example, be byproducts of the method in FIG. 1 . For instance, with reference to FIG. 1 , when request 124 was received at request server 114 , then step 126 can be associated with generating row 422 , which indicates that transaction “T1234” is in a status of “request received at requestor” and occurred at a time “12:32:56:09.” As processing continues to business server 116 , row 424 may be generated during step 128 . Instead of overwriting the old data, the present invention enters a new row, row 424 , to indicate a status transition to “processing business data.”
The data model of the present invention provides that only a single table, request-audit table 414 , needs to be updated rather than multiple tables as has historically been the case. That is, tables 410 and 412 do not need to be updated incident to a transaction-status change. Thus, when request 124 advances toward completion to network server 118 , then during step 130 , row 426 may be generated. Row 426 indicates that transaction ID “T1234” is associated with a status of “building switch command” at a time of “12:33:00:15.” Again, even though the status of the transaction at issue changed, tables 410 and 412 do not need to be modified. Moreover, adding row 426 (as opposed to overwriting old data) creates an audit trail.
In a final illustrative step, row 428 is created when the status of request 124 transitions to “update sent to network.” From table 414 , it is clear that an audit trail has been established that marks the progression of the transaction request. Although only four transaction-status updates are shown, any number of status updates can be logged in accordance with an embodiment of the invention. That is, if a carrier wishes to log any number of events, then this functionality is offered by the present invention. A carrier, or other user, may wish to log five, ten, fifty, or however many steps of a request transaction. Each can be logged, and an audit trail associated with those events can be easily created.
The time stamps in column 420 denote the time associated with each event, or step, of a request transaction. Having this audit trail available enables a user to establish benchmarks and to evaluate problems associated with a communications network. For instance, if there was a large time gap between when the request was received at the requestor and when the business server 116 received request 124 , then a determination can be made that interim processes are not operating efficiently. A difference between any two or multiple time stamps can be used to identify inefficiencies.
The present invention also enables inefficiencies to be associated with individuals. For instance, if a transaction analyst was responsible for insuring that data be communicated from network server 118 to communication server 120 , but a consistent time gap consistently appears between when a request leaves network server 118 and when it reaches communication server 120 , then it can be reasonably inferred that the person in charge of the task at issue may need to be trained on how to route data more effectively. The person, code segment, or other mechanism responsible for routing a request from a first component to a second component can be trained or optimized to route data more efficiently when unacceptable time gaps are observed.
The data model of FIG. 4 also makes recovering from error transactions much easier than has historically been possible. The audit trail of request-audit table 414 allows an analyst to view a transaction progression from when it starts to when it faults and everything in between. Thus, no visibility is lost from when a first transaction status transition to a second transaction status. As shown in FIG. 4 , historical transaction data is maintained separately from the business data of tables 410 and 412 . This structure ensures that transaction statuses are not overwritten when new statuses arrive and it eliminates the problem of having redundant transaction data spread across multiple tables. No longer do multiple tables need to be accessed and information gathered about the transaction to determine, or attempt to determine, when a transaction entered into a fault status.
The tables shown in FIG. 4 are overly simplified so as to not obscure the present invention. But in practical applications, switch tables may include several tens of columns and thousands or hundreds of thousands of rows. Moreover, transaction data is often stored across several tables, not merely two. Also, table 414 indicates only two transaction data items: transaction status and transaction time stamp. But in practice, a transaction may be associated with several or even tens of columns of data rather than merely two.
An exemplary method for processing a switch transaction follows. A transaction request is received. User data is formatted by a business-side process and the transaction is associated with respect to business data. The information from the business data is placed into a transaction table to be communicated to one or more switches. A distributor then distributes the information to the appropriate switches. After the switches process their respective updates, switch responses are received. The information received from the switches is formatted into one or more response tables. Finally, the transaction is denoted as successful or not. Because of these steps and the way a configuration transaction, another name for request 124 , is processed, both the idea and implementation of a data structure that maintains business-type data separately from transaction-type data is nonobvious. Because a communications network grows over time, legacy systems have business data intimately entwined with transaction data. Separating transaction data from business data at the table level is a resource-intensive process that requires a paradigm shift, whereby a focus is placed on processing transactions rather than merely retrieving data.
Turning now to FIG. 5 , which is an exemplary method for facilitating telecommunications network configuration-transaction processing in a switch. In step 510 , the switch receives a network configuration transaction. The switch processes the configuration transaction and maintains a first table that stores transaction-independent data, in step 520 . Also, in step 530 , the switch maintains a second table that stores transaction-dependent data. In turn, a transaction identifier is utilized to link the first and second table, in step 540 . In step 550 , predefined substeps associated with the network configuration transaction update the second table having the transaction-dependent data.
Historically, systems were data centric where tables were wrappers around a resource such as a switch. The present invention is centered around transactions and tracking those transactions rather than mere data. Historically, the central focus and objective was to have a switch store certain data and then mirror that same data in local tables. Moreover, there was little focus on the status of a switch transaction as it progressed through various components. That is, a primary emphasis was placed on attaining a final status, but little emphasis was placed on monitoring the subprocesses that ripened into the final status. Transaction requests were viewed almost as afterthoughts as a means to arrive at a goal.
But the present invention stems from a realization that the journey is as important, if not more important, than the destination. The present invention reflects a more comprehensive view where the transaction itself is the center of focus. Emphasis is placed on how a transaction is processed. That is, observing the transaction yields an indication of desired data rather than merely focusing on switch data to mimic its contents into local tables.
As can be seen, the present invention and its equivalents are well-adapted to increasing the efficiency of a communications network. Many different arrangements of the various components depicted, as well as components not shown, are possible without departing from the spirit and scope of the present invention. Those skilled in the art will appreciate the litany of additional network components that can be used in connection with the present invention.
The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art that do not depart from its scope. Many alternative embodiments exist but are not included because of the nature of this invention. A skilled programmer may develop alternative means of implementing the aforementioned improvements without departing from the scope of the present invention.
It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims. Not all steps listed in the various figures need be carried out in the specific order described. Not all steps of the aforementioned flow diagrams are necessary steps.
|
A method and data structure for monitoring the progression of a configuration transaction through a communications network is provided. The method includes creating an audit trail associated with the switch-transaction progression, iteratively updating the audit trail incident to an occurrence of a designated transaction-processing substep without overwriting previously stored data, and processing the audit trail so that it is available for access via a user interface. Historical data tracking the configuration transaction's process is preserved rather than overwritten.
| 8
|
BACKGROUND OF THE INVENTION
This invention concerns a structure for anchoring a rod, pile or the like (hereinafter called a "rod" or "anchor rod") into concrete, rock or similar material (hereinafter called "concrete") by means of a cementing material such as a resin adhesive.
Such an anchoring method is commonly used for fixing structural members, machinery, equipment, temporary structures and the like in concrete. A typical such structure anchoring is illustrated in FIG. 6 (a). As shown in this figure, an anchor rod 1 is fixed in concrete 3 by means of a cementing material 2 which fills the empty portion of an anchor hole 4. FIGS. 8 and 9 respectively illustrate a deformed bar and a threaded bolt which are anchored by this method. The cementing materials which are normally used include epoxy resins, polyester resins and non-contracting cement.
This anchoring method has the advantages that a high positioning accuracy is easier to attain than with other methods, it provides a high-strength anchorage, and it can be rapidly performed. For these reasons, it has been acquiring increasing acceptance in various fields. For example, in the field of civil construction, it is used for anchoring bridge supports, bridge pier studs and shutter supports. In the field of architectural construction, it is used for anchoring exterior equipment, piping brackets, slab reinforcement elements, exterior sign boards and other members.
However, this method can still not be said to have become well established. Reliable design criteria for it are not yet available. Although not very often, pullingout of an anchor and/or concrete fracture around an anchor actually occurs, especially with larger anchors whose failure is very serious. The reasons for such failures may be related to inadequacies in anchor design.
One of the unique features of these pullout fractures or concrete fractures is that, as shown in FIG. 6 (b), the anchor 1 is pulled out together with a cone-shaped piece of concrete 6 (hereinafter called a "cone"), the anchor and the cone 6 resembling the shape of a mushroom.
As a result, a crater-shaped hole is produced in the surface of the concrete body. The hole decreases the load bearing capacities of the nearby anchors, can cause them to fail, and can finally even cause the object which is supported by the anchors to fall down.
One of the reasons why such troubles occur more often with larger anchors may be attributable to the fact that it is very difficult to test larger anchors and there is not so much laboratory or field testing data on them. In many cases, larger anchors have been designed by extrapolating data for smaller anchors on which testing is far easier to conduct and for which much data is readily available.
SUMMARY OF THE INVENTION
It was found by the present inventors that the apparently irregular cone-shaped concrete fracture of adhesive anchors is in fact a highly regular physical phenomenon. As shown in FIGS. 7 (a)-7 (c), cone-shaped fractures occur at intervals of approximately 1.8 times the hole diameter.
In this invention, a structure is proposed in which an anchor rod is physically insulated from the concrete sides of a hole to a depth corresponding to the height of the uppermost cone. As a result, cone fracture can be prevented, the anchor load can be led deeper into concrete, and a more reliable anchorage can be realized.
The inventors also studied the mechanism by which the anchoring strength of adhesive anchors is determined, and it was found that an increase in the hole diameter has a negative effect on the anchoring strength. The inventors therefore devised an anchoring structure in which this negative effect can be reduced or totally eliminated.
The present invention is an anchoring structure in which an anchor rod is secured inside a hole in a concrete body by means of a cementing material. The rod is insulated from the concrete to a prescribed depth so that there is no shearing force acting on the sides of the hole to the prescribed depth. The insulation may be provided by a sleeve-shaped insulating space having a depth which is at least 1.5 times the hole diameter. The insulating space may be filled with a sleeve. The rod is provided with a continuous ring-shaped or spiral-shaped groove or grooves and/or a thread or threads, the depth or height of the groove of thread being larger than the maximum crack width to be expected in its neighborhood. The side surfaces of the groove and/or thread under the concrete have a slope in the range of 15°-50°.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an anchorage structure in accordance with this invention wherein (a) shows an overall scheme and (b) shows an enlarged section and illustrates the anchoring mechanism.
FIGS. 2 (a) and (b) are transverse cross sections of two examples of insulating sleeves.
FIGS. 3 (a) and (b) and FIGS. 4 (a) and (b) illustrate the mechanical principles underlying this invention.
FIG. 5 is a graph comparing experimental data on anchoring strength as a function of diameter for anchors according to this invention and for conventional anchors.
FIGS. 6 (a) and (b) and FIGS. 7 (a), (b) and (c) show the modes of concrete fracture of conventional adhesive anchors.
FIGS. 8 (a) and (b) and FIGS. 9 (a) and (b) illustrate a conventional adhesive anchor structure and its operating principles.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 6 and 7 will be referred to in order to explain the modes of concrete fracture of an anchoring structure. In these figures, element number 1 is an anchor rod, 2 is a cementing material, 3 is concrete, 4 is an anchor hole, 6 is a fractured concrete cone, 61 shows the position where the first cone fracture starts, 62 shows the starting position of the second cone fracture, and 63 shows the starting position of the third cone fracture.
An anchor fracture can be explained as follows. When a load is applied to an anchor rod, it produces a shear stress around the anchor rod. When the shear stress reaches the uniaxial shear strength of concrete, the concrete adjacent to the layer of cementing material is sheared off, producing two uneven surfaces. The layer of cementing material does not normally fracture as it is stronger than the concrete. A relative sliding movement between the two uneven surfaces takes place due to the shear stress acting there and such sliding of uneven surfaces in a confined space induces an immediate mutual engagement again due to a kind of wedge action and produces a radial compressive stress perpendicular to the anchor axis, which in turn produces a high frictional resistance there. The radial compressive stress increases the shear strength of concrete far above the uniaxial strength around the anchor by the action of Coulomb's internal friction. The internal and external frictional resistance is the real source of the strength of adhesive anchors.
On the other hand, when the shear fracture of concrete around an anchor occurs, the first cone fracture starts at the depth shown by 61 in FIG. 7, absorbing the strain energy stored in the shallower portion of concrete. This cone fracture is caused by the shock of the shear fracture of the concrete. This cone fracture takes its form gradually as the load increases, while the load bearing capability of the shallower portion is soon totally lost well below the ultimate pullout load.
When the load exceeds the above-mentioned frictional resistance appearing in the portion of the anchor which is deeper than the position where the first cone fracture has started, the final sliding-out of the anchor rod starts and induces the second and third cone fractures at the deeper positions 62 and 63 shown in FIG. 7. The frictional resistance in the deeper portion virtually constitutes the pullout strength of anchors mortared with a sufficiently strong cementing material. The second and third cone fractures little affect the ultimate pullout strength of anchors but damage the concrete body seriously by producing a large, deep crater-shaped hole which may lower the load bearing capacities of the nearby anchors.
A test was conducted to prove the above-described theory using actual anchors. The hole diameter was 34 mm, the depth was 300 mm, the anchor bolt diameter was 30 mm, its length was 400 mm, and an epoxy resin adhesive was used as a cementing material. The anchors were cured for several days after installation.
By analyzing the results of the above test together with the test results available from other sources, it was found that the depth of the position 61 where the first cone fracture starts is in the range of 1.5-2.25 times the anchor hole diameter.
The above-mentioned radial compressive stress which appears when the concrete has been sheared off near the surface of the cementing material under tensile (compressive) loading is represented approximately by Eq. 1 and the resultant anchoring strength by Eq. 2. ##EQU1## where σ d =radial compressive stress
E c ≈inital Young's modulus of concrete
v=unevenness of the sheared concrete surface (average height of the unevenness)
P m =anchor pullout load (anchor strength)
μ=coefficient of friction of the sheared surfaces of concrete
D=anchor hole diameter
L'=effective anchor depth
(L'≈L-1.82×D)
L=anchor hole depth
The average unevenness and the coefficient of friction in the above equations do not vary much even when the hole diameter is varied. It can be seen from Eq. 1 that the radial compressive stress is nearly inversely proportional to the hole diameter and from Eq. 2, it can be seen that the anchoring strength does not increase as the hole diameter increases. It can be said that an increase in the size of the anchor hole obviously has a negative effect on the anchoring strength.
This negative effect is brought about by a reduction in the radial compressive stress due to an increase in the anchor hole diameter. This invention compensates for the reduction in the compressive stress by introducing other mechanisms that generate an additional radial compressive stress. As shown in FIG. 4, when relative movement takes place between the thread surface 60 of an anchor rod and a cementing material 20, force components P 1 , P 2 and P a , P b are generated on the thread surface, wherein (P a -P b ) is a newly generated radial compressive stress due to wedge action. The relative movement can appear as a deformation flow of the cementing material and/or a slip of the cementing material on the thread surface. However, in the case of a deformed rod as shown in FIGS. 8 (a) and (b), which is a typical example of a conventional adhesive anchor, the spacing between the adjacent ribs (threads) 8 is so large that the radial compressive stress generated there can not be very large, since it is dispersed over the entire surface. Thus, the resulting improvement in the anchoring strength is insignificant.
In the case of another conventional example wherein a bolt 9 with an ordinary thread 11 is used as shown in FIGS. 9 (a) and (b), the inclination of the thread surface is 60° which is too steep to allow a relative movement of the cementing material to generate a sufficient radial compressive stress.
An embodiment of this invention will now be explained referring to FIG. 1.
An anchor rod 10 is secured by means of a cementing material in a hole 40 drilled into a concrete body 30. A sleeve-shaped space 50, which is deeper than 1.5 times the diameter of the hole 40, is provided around the anchor rod 10 and a sleeve 70 is inserted into the space 50. A continuous thread having a slope of 15°-50° 60 is formed on the surface of the rod 10. The height (the distance from the root to the crown) of the continuous thread 60 is chosen to be larger than the maximum crack width which is expected to appear in the nearby concrete. If the slope of the thread 60 is less than 15°, it does not produce a sufficiently high radial compressive stress, and when it is greater than 50°, it is too steep and prevents the cementing material from flowing and/or slipping, so a radial compressive stress does not appear. If the thread height is inadequate, the appearance of a crack in the nearby concrete would make the above mechanism more or less inoperative since the deformation of cementing material would be largely or fully absorbed by the internal deformation of the concrete due to cracking.
The application of a separating agent such as silicone grease that prevents adhesion between the cementing material and the thread surface and lowers frictional resistance is effective for producing a higher compressive stress.
FIG. 5 compares the pullout strengths for various hole diameters of three different anchor systems. The triangles show the results for an anchor system incorporating a rod according to this invention as shown in FIG. 1, the x marks show the results for a conventional deformed bar 7 like that shown in FIG. 8, and the circles show the results for a conventional bolt anchor 9 like that shown in FIG. 9. The compressive strength of the concrete body used for testing was 210 kg/cm 2 , the hole diameters were 20, 30, 40, and 50 mm, and the hole depths were 7 times the hole diameter.
FIG. 5 clearly shows that the pullout strength of an anchor according to this invention is significantly higher than the pullout strength of conventional anchors. The larger the anchor diameter, the larger the improvement. An anchor according to this invention having a hole diameter of 30 mm gives a strength of 26.5 tons, and a conventional deformed bar anchor or bolt anchor with the same diameter gives a strength of 20.5 or 21.2 tons, respectively. As shown in FIG. 5, the differences among the strengths increase as the hole diameters increase. An anchor according to this invention is pulled out by gradual sliding after its maximum strength has been reached. As shown in FIG. 3 (b), the anchor has a popsicle-like shape after being pulled out, the rod being covered with the hardened cementing material and carrying some concrete fragments with it. Only a small hole is left behind in the concrete body after the rod has been pulled out. No large cone fracture of the concrete takes place.
When the aforementioned insulating sleeve 70 is used, the space between the rod 10 and the sleeve 70 can be filled tightly with the cementing material 20 so that the rod 10 in the hole is protected from rusting while the required physical insulation is ensured to prevent the first cone fracture from occurring.
The insulating sleeve 70 can be made of an elastic pipe 80 or 90 having a split 100 formed there, as shown in FIGS. 2 (a) and (b). Due to spring action, such a sleeve 70 fits firmly inside the insulating space 50 in the upper portion of the anchor hole.
Another method of providing insulation between the anchor rod and the concrete is to apply a separating agent on the concrete surface 5 of the insulating space and leave the insulating space unfilled or filled with a material such as an organic filler.
As described in detail above, an adhesive anchor according to this invention can provide a high anchoring strength which is a direct result of the increased internal and external friction of the concrete around the anchor caused by an increase in the radial compressive stress brought about by the applied load through a wedge action. Therefore, the nearby concrete can be kept intact even after the anchor has been pulled out, and a chain-reaction failure, which is the most feared occurrence in a multi-anchor system in a row or grid installation, is prevented. Pullout of an anchor according to this invention does not damage other nearby anchors or the concrete, and it leaves only a small hole where the anchor was. Therefore, the entire structure in which the anchor is used is less susceptible to structural damage originating from an anchor failure.
The mechanical insulation as described above can be easily provided by enlarging the hole diameter slightly to the required depth and inserting a sleeve with an outer diameter which fits the enlarged hole.
|
An anchoring structure comprises an anchor rod which is secured to the inside of an anchor hole in concrete by a cementing material except for an upper section of the rod having a depth of at least 1.5 times the diameter of the anchor hole. The upper end of the anchor rod may be surrounded by an insulating sleeve which fits into the upper section of the anchor hole. The anchor rod may have a continuous groove formed therein, at least one surface of which has a slope of 15°-50°. The depth of the groove is at least as large as the maximum crack width expected to appear around the anchor in the concrete.
| 4
|
RELATED APPLICATION
[0001] This application claims provisional priority of U.S. Provisional Patent Application Serial No. 60/358,046, filed Feb. 19, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a tong including a continuous composite belt and methods for making and using same.
[0004] More particularly, the present invention relates to a tong including a handle assembly, a jaw assembly, a hook plate assembly and a continuous composite belt, where the belt is secured to the hook plate and jaw assemblies and methods for making and using the tong to rotate or turn a pipe.
[0005] 2. Description of the Related Art
[0006] Current tongs for use in the oil industry and other related industries use linked chains to wrap around the piping so that the pipe can be broken-down or made up. Although these linked chains are manufactured to high precision and to withstand pressure well in excess of their operating limits. However, when such linked chains fail, the chains can cause metal pieces to be ejected from the chain at relatively high velocity.
[0007] Thus, there is a need in the art for a tong apparatus including a continuous composite belt in place of a chain to reduce down time in the event of a tong failure and to reduce the risk of harm to personnel and/or other equipment in the event of tong failure.
SUMMARY OF THE INVENTION
[0008] The present invention provides a tong apparatus including a continuous composite belt adapted to act, along with the a jaw, as the pipe engaging part tong, where the word continuous means that the belt is in the form of a loop like a rubber band.
[0009] The present invention provides a tong apparatus including a handle, a jaw, and a continuous composite belt.
[0010] The present invention provides a tong apparatus including a handle assembly, a jaw assembly, a hook plate assembly and a continuous composite belt.
[0011] The present invention provides a tong apparatus including a handle, a jaw, a jaw pin, a continuous composite belt, a top hook plate, a bottom hook plate, a hook pin, hook grip pins and a latch pin.
[0012] The present invention provides a tong apparatus including a handle, a jaw, a jaw pin, a continuous composite belt, a top hook plate, a bottom hook plate, a hook pin, hook grip pins, a latch pin and a hanger.
[0013] The present invention provides a tong apparatus including a handle, a jaw, a jaw pin, a continuous composite belt, a top hook plate, a bottom hook plate, a hook pin, a hook grip pin, a latch pin, a spring, a hanger, and a bumper.
[0014] The present invention provides method for turning a pipe including detaching one end of the belt from a tong apparatus of this invention including a continuous composite belt, wrapping the belt around the pipe, positioning the tong apparatus at a desired position on the pipe, reattaching the end of the belt to the tong, and applying a force to the handle of the tong to turn the pipe.
DESCRIPTION OF THE DRAWINGS
[0015] The invention can be better understood with reference to the following detailed description together with the appended illustrative drawings in which like elements are numbered the same:
[0016] [0016]FIG. 1 depicts a top plan view of one preferred embodiment of the tong apparatus of this invention;
[0017] [0017]FIG. 2A depicts a top view of a preferred embodiment of a handle assembly of the tong apparatus of FIG. 1;
[0018] [0018]FIG. 2B depicts a side view of the handle assembly of FIG. 2A;
[0019] [0019]FIG. 2C depicts a front view of the handle assembly of FIG. 2A;
[0020] FIGS. 3 A-D depict a top and side views of belt constructions of this invention;
[0021] FIGS. 3 E-I depict views of surfaces of the belts of FIGS. 3 A-D;
[0022] [0022]FIG. 3J depicts a top view of a belt construction having angled ribs and valleys;
[0023] [0023]FIGS. 3K&L depict sides views of preferred embodiments of two ply belts;
[0024] [0024]FIGS. 3M&N depict a top view and side view, respectively, of a preferred embodiment multi-ply belt;
[0025] [0025]FIG. 4A depicts a top view of a top hook plate of FIG. 1;
[0026] [0026]FIG. 4B depicts a top view of a bottom hook plate of FIG. 1;
[0027] [0027]FIG. 5A depicts a front view of the jaw assembly of FIG. 1; and
[0028] [0028]FIG. 5B depicts a side view of the jaw assembly of FIG. 5A.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The inventors have found that a tong can be constructed using a continuous composite belt instead of a linked chain to engage a pipe, casing or the like to turn the pipe. The inventors have found that the continuous composite belt yields a lighter weight tong with improved safety because catastrophic failure of a linked-chain can result in a risk of injury to workers due for example to flying metal fragments, while failure of the continuous composite belt would reduce or substantially eliminate any worker risk. Moreover, the inventors have found that tongs including continuous composites belts are easier to attach, maintain, and adjust compared to tongs with traditional linked chain engaging members. Furthermore, the inventors have found that tongs including continuous composite belts allow for faster and easier field repair, because when a belt fails, a new belt can be attached quickly by simply removing two pins in the tong.
[0030] The tongs of this invention share some structural elements of traditional linked chain tongs. The tongs include a jaw assembly pivotally mounted on, connected to or attached to a handle assembly. The jaw assembly and belt are adapted to engage a pipe allowing the pipe to be rotated or turned. The continuous belt is adapted to engage a portion of the pipe and the jaw is adapted to engage the same portion of the pipe, but opposite the belt. The belt is anchored to the tong at two places using removable pins. Preferably, the belt attaches at one end to the jaw assembly and at the other end to the hook assembly via the pins. Optionally, the belt can be tightened about the pipe. Once the belt is looped about the pipe and reattached to the tong and optionally tightened about the pipe, the tong permits force to be transferred from the handle assembly to the pipe via the belt and jaw resulting in rotation of the pipe.
[0031] The continuous composite belts to be used in the tongs of this invention include a polymeric matrix reinforced by longitudinally extending continuous fibers, yarn, woven strings, wires, fiber bundles, wire bundles, fabric, meshes or mixtures or combinations thereof. In the case of continuous fibers, strings, yarn, wires or bundles, they generally run parallel at a desired spacing relative to the width of the continuous belt. Preferably, the spacing is sufficient to allow complete encapsulation of each fiber, wire or bundle in the polymeric matrix. Although continuous fibers, yarns or woven strings are preferred, thin metal wires can also be used or a combination of fibers and metal wires or bundles comprising fibers and wires can be used. In the case of fabric and/or meshes, the fabric preferably has sufficient openings to allow the matrix material to embed the fabric or mesh.
[0032] Suitable polymeric matrices for use in the continuous belts of this invention include, without limitation, any type of thermoplastic or thermosetting material such as elastomers, thermoplastic elastomers, epoxy resins, phenolic resins, urethanes, or mixtures or combinations thereof. Generally, the matrices are cured with the fibers, yams, string, wires or bundles embedded in the matrix. The curing can be accomplished by any curing method known in the art depending on the nature of the polymers making up the matrix including, without limitation, radiation curing, heat curing, light curing, or mixture or combinations thereof. The curing can also be enhanced or accelerated by chemical cure system as is well known in the art. The matrices can also include additives such as filler including carboneous fillers such as carbon black or the like, fiber fillers such as chopped fibers including the fibers set forth below for the continuous fibers, and inorganic fillers such as silica, clay, calcium carbonate, zeolites, mordenites, fugacites, or the like or mixtures or combinations thereof. For further details relating to polymeric matrices and/or their cure systems the readers is directed to the following U.S. Pat. Nos.: 3,257,346, 3,517,722, 3,738,948, 3,931,090, 3,933,732, 4,130,519, 4,605,696, 4,633,912, 4,684,421, 5,254,616, 5,091,449, incorporated herein by reference. The matrices can also include anti-degradants such as anti-oxidants, anti-ozonants, or the like, plasticizers, flow enhancers, or the like.
[0033] Suitable continuous fibers, yams or woven string for use in this invention include, without limitation, carbon fibers, boron-nitride fibers, polyamide fibers, polyimide fibers, glass fibers, or mixtures or combinations thereof. The fibers can be also coated with a bonding material and/or chemically and/or physically treated to increase adhesion between the matrix and the fiber. Such treatments can also include physical treatments such as ion bombardments or ion implantations. Although many of these treatments may increase adhesion and/or bonding interactions between the fiber and the matrix, these treatments tend to reduce the tensile strength of the fibers. Therefore, the treatments are used only when the treated fiber has adequate tensile strength for the intended application.
[0034] Suitable metal wires include, without limitation, iron alloy wires or other similar metal wires having high tensile strengths. Generally, iron alloy wires are coated with a micro bonding layer including copper, zinc, cobalt, brass, bronze, nickel, or the like or mixture or combinations thereof. These coating improve the adhesion and/or bonding between the metal surface and polymeric matrix.
[0035] Preferred belts are manufactured by Roblon A/S and sold by Tasmanian Tool Company, Inc. of Lafayette, La.
[0036] Referring now to FIG. 1, one preferred embodiment of a tong apparatus, generally 100 , of this invention is shown to include a handle assembly 200 , a continuous composite belt 300 , a hook plate assembly 400 and a jaw assembly 500 , where the tong 100 is adapted to engage a surface 102 of a pipe 104 so that the pipe 104 can be rotated or turned. The apparatus 100 also includes a hanger 106 adapted to allow the apparatus 100 to be hung when attached to vertically oriented pipe. The apparatus 100 also includes a belt pin 108 , which can be held in place with a retaining ring 110 . The apparatus 100 also includes alignment and spacing bolts 112 . The apparatus 100 also includes a handle pin 114 (shown as a latch pin here), where the handle pin 114 is adapted to pivotally mount the hook plate assembly 400 on the handle assembly 200 . The apparatus 100 also includes a jaw pin 116 , which can be held in place with a retaining ring 118 and adapted to pivotally mount the jaw assembly 500 on the handle assembly 200 .
[0037] Referring now to FIGS. 2 A-C, the handle assembly 200 includes a handle 202 , a jaw pin aperture 204 , a hook plate assembly pin aperture 206 and a hanger aperture 208 . The handle 202 is adapted to transmit rotational force to the pipe 104 via the belt 300 and the jaw assembly 500 . The jaw pin aperture 204 is adapted to receive the jaw pin 116 and to allow the jaw assembly 500 to be pivotally mounted on the handle 202 . The hook plate assembly pin aperture 206 is adapted to receive the hook pin 114 and to allow the hook plate assembly 400 to be pivotally mounted to the handle 202 . The hanger aperture 208 is adapted to receive a hanger 106 . The handle assembly 200 optionally includes an end aperture 210 for hanging the tong 100 , when not in use. Looking at FIG. 2A, the handle assembly 200 is of a general triangular shape with each aperture 206 , 208 and 210 at the vertices of the triangle. Looking at FIGS. 2B&C, the handle 202 includes a rectangular-shaped head 212 which tapers to a rectangular tail 214 . The rectangular head 212 includes a jaw receiving cavity 216 and jaw pin protrusions 218 . The cavity 216 is designed to allow the jaw assembly 500 to pivot when mounted on the handle assembly 200 .
[0038] Referring now to FIG. 1 and FIGS. 3 A-D, two illustrative examples of belts, generally 300 , are shown as comprising a high tensile strength fiber reinforced polymeric matrix 302 including a plurality of spaced apart, parallel and longitudinally extending continuous fiber bundles 304 encased or embedded in the polymeric matrix 302 . Looking at FIGS. 3A&B, one embodiment of the belt 300 is shown to include two smooth surfaces 306 and 308 . Looking at FIGS. 3C&D, another preferred embodiment of the belt 300 is shown to further include laterally extending teeth, ribs or ridges 310 and valleys or grooves 312 on the surface 306 which becomes the pipe engaging surface.
[0039] Referring now to FIGS. 3 E-I, several illustrative examples of ribbed belts 300 are shown. Looking at FIG. 3E, the ribs 310 and the valleys 312 are substantially rectangular (where rectangular includes a square) in shape. Looking at FIG. 3F, the ribs 310 and the valleys 312 are shown as substantially trapezoidal in shape. Looking at FIG. 3G, the ribs 310 are substantially dome shaped and the valleys 312 are substantially rounded rectangles in shape. Looking at FIG. 3H, the ribs 310 and the valleys 312 are non-symmetric trapezoids in shape, where each trapezoid have a vertical edge 314 and a slanting edge 316 giving rise to a right-hand oriented rib pattern 318 . Looking at FIG. 3I, the ribs 310 and the valleys 312 are non-symmetric trapezoids in shape, where each trapezoid have a vertical edge 320 and a slanting edge 322 giving rise to a left-hand oriented rib pattern 324 .
[0040] Of course, one of ordinary skill in the art can clearly recognize that other rib and valley geometrical shapes can be constructed and that the belts could include mixtures or combinations thereof. In fact, the ribs and valleys do not have to extent longitudinally, but can extend at an angle as shown in FIG. 3J, where the belt 300 has angled ribs 310 and valleys 312 .
[0041] Alternatively, the belt can include more than one ply of reinforcing fibers. In one preferred embodiment of a multi-ply constructions, two fiber reinforced plies are simply staked one on top of the other. Referring now to FIG. 3L, a preferred embodiment of a two-ply belt 320 is shown to include a first reinforced ply 322 and a second reinforced ply 324 , where the fibers or fiber bundles 326 and 328 of the plies 322 and 324 , respectively, are aligned one on top of the other. Referring now to FIG. 3B, another preferred embodiment of a two-ply belt 320 is shown to include a first reinforced ply 322 and a second reinforced ply 324 , where the fibers or fiber bundles 326 and 328 of the plies 322 and 324 , respectively, are offset. Referring now to FIGS. 5C&D, a preferred embodiment multi-ply belt 350 is shown to include a first reinforced ply 352 and a second reinforced ply 354 separated by a matrix ply 356 . In the first ply 352 , fibers or fiber bundles 358 are biased and extend at a first angle α relative to a central longitudinal axis 360 , while in the second ply 354 , fibers or fiber bundles 362 are also biased and extend at a second angle β, where β preferably is equal to −α as shown. Because the reinforcing plies are cut on a bias, the belt 350 will also preferably include longitudinally extending end caps 364 comprising the polymer matrix to protect the cut ends of the fibers or fiber bundles. Of course, the number of plies can be increased limited only to thickness and weight considerations.
[0042] Referring now to FIG. 1 and FIGS. 4A&B, the hook plate assembly 400 includes a top plate 402 and a bottom plate 404 . Each plate 402 and 404 includes a belt pin aperture 406 with retaining ring 110 , a handle pin aperture 408 , and an auxiliary aperture 410 . The auxiliary aperture 410 is used to adjust the tong 100 by moving the hook plate assembly 400 so that the auxiliary aperture 410 aligns with the hook plate assembly pin aperture 206 of the handle assembly 200 . The belt pin aperture 406 is adapted to receive and retain the belt pin 108 by retaining ring 110 . The handle pin aperture 408 is adapted to receive and retain the handle pin 114 , which is a latch pin. The auxiliary pin aperture 410 is adapted to facilitate the use of the tong 100 with a coupling in lieu of the pipe body. The pin aperture 410 can also include a retaining ring (not shown). The embodiment of FIG. 1 shows the belt pin 108 to have a retaining ring 110 , while the handle pin 114 is a latch pin. In another preferred embodiment, the belt pin 108 is a latch pin and the handle pin 114 has a retaining ring. In yet, other preferred embodiments, both the belt pin 108 and the handle pin 114 include retaining rings or both are latch pins.
[0043] The belt retaining pin 108 is adapted to be inserted through the first end 306 of the belt 300 (see FIG. 1) so that the belt 300 is positioned between the two plates 402 and 404 . Each plate 402 and 404 is in the form of a complex curvilinear shape 414 having a jaw engaging concave region 416 , three other concave regions 418 a - c and four convex regions 420 a - d . Of course, one of ordinary skill in the art should recognize that the exact shape of the hook plates 402 and 404 can be of any shape. The hook plates 402 and 404 also include two alignment apertures 422 adapted to receive the alignment and spacing bolts 112 .
[0044] Referring now to FIGS. 5A&B, the jaw assembly 500 includes a body 502 having a jaw pin aperture 504 adapted to receive the jaw pin 116 . The jaw pin 116 is adapted to be inserted through the jaw aperture 504 and through the handle assembly 200 to pivotally mount the jaw assembly 500 on the handle assembly 200 and retain the other end 308 of the belt 300 (see FIG. 1). The jaw assembly 500 also includes a reinforcing cross member or web 506 , a front flange 508 , a rear flange 510 , sides flange 512 and a side plate 514 . The jaw assembly 500 also includes toothed pipe engaging members 516 situated on side flanges 512 .
[0045] One of ordinary skill in the art should recognize that other designs of a handle assembly, a jaw assembly and a continuous composite belt can be constructed to accomplish the same goal of this invention, which is a tong including a continuous composite belt to engage and turn the pipe instead of a linked metal chain or other metal chain like device. The continuous composite belt constructed of a fiber or wire reinforced polymer matrix does not fail in a potentially dangerous fashion as is the case for metal linked pipe engaging devices associated with a conventional tong.
[0046] When using the tong 100 of FIG. 1, the belt end 306 is taken off by removing one of the hook plates 402 or 404 . The belt 300 is then wrapped around the pipe 104 . The belt end 306 is then slipped back over the belt pin 108 and the hook plate 402 or 404 reset and the pins latched or retained in place. The handle 202 can then be used to impart a torque to the pipe 104 via the belt.
[0047] All references cited herein are incorporated by reference. While this invention has been described fully and completely, it should be understood that the invention may be practiced otherwise than as specifically described. Although the invention has been disclosed with reference to its preferred embodiments, from reading this description those of skill in the art may appreciate changes and modification that may be made which do not depart from the scope and spirit of the invention as described above.
|
A manual tong is disclosed which includes a continuous composite continuous belt, a handle assembly, and a jaw assembly, where the continuous composite continuous belt is designed to take the place of the convention linked chains used currently in manual tongs. The continuous composite continuous belt is held in place by a set of pins associated with the handle and jaw assemblies. Replacement of the linked chains with the continuous composite continuous belts improve tong safety, improve ease of use, lower cost, make adjustment easier and make continuous belt replacement easier reducing down time and increasing tong utility (one tong can be used for different pipe diameters with a simply adjustment of the continuous belt or a simple replacement of the continuous belt with a different size continuous belt.
| 4
|
CROSS REFERENCE TO RELATED PATENT APPLICATIONS
[0001] This patent application is a divisional application of co-pending, commonly owned U.S. patent application Ser. No. 11/759,415, filed Jun. 7, 2007, entitled “Cargo Roller Tray Shear Fitting,” which is hereby incorporated in its entirety by reference.
TECHNICAL FIELD
[0002] Embodiments of the disclosure relate to shear fittings in general and shear fittings used to fasten structures to support beams of aircrafts.
BACKGROUND
[0003] Cargo roller trays are used in vehicles (e.g., air craft, ships, trucks, etc.) and storage locations (e.g., holds, containers, and warehouses, etc.) to speed the movement of cargo. Typically, the cargo roller trays are joined to structural supports (e.g., floor beam, floor joists, etc) or a floor using fasteners.
[0004] The cargo roller trays in the past have been attached to structural supports by positioning the cargo roller tray on the support, drilling holes through both the cargo roller tray and the support, and then inserting fasteners though the holes. This fastening process required the installer to drill holes and to clean up the drill shavings after the holes were drilled. This process also required the use of backing plates for the fasteners, since the tension in the fastener held the cargo roller tray in position.
[0005] In an effort to speed the assembly process, both the support and the cargo roller tray are predrilled. However, when the holes in the cargo roller tray and the support did not line up, re-work was required
[0006] Accordingly, there is a need for a shear fitting that can fasten a structure such as a cargo roller tray to the support such that re-work is minimized when using predrilled components.
SUMMARY
[0007] Embodiments of the disclosure may advantageously address the problems identified above by providing, in one embodiment, a shear fitting for joining a structure such as a cargo roller tray and/or at least a portion of a passenger cabin to a support beam. The shear fitting includes a base plate and parallel lugs extending from the base plate.
[0008] The shear fitting may include a base plate having a slot to fasten the shear fitting to the support beam. The shear fitting may additionally include parallel lugs having lug apertures to fasten the shear fitting to the structure. The slot may permit the shear fitting to shift (traverse) a predetermined distance along a length of the support beam.
[0009] In some situations, the shear fitting may be used in aircrafts to join structures such as an aircraft cargo roller tray and/or at least a portion of a passenger cabin to a support beam.
[0010] The features, functions, and advantages that have been discussed can be achieved independently in various embodiments of the present disclosure or may be combined in yet other embodiments further details of which can be seen with reference to the following description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The accompanying drawings incorporated in and forming part of the specification illustrate several embodiments of the disclosure. In the drawings:
[0012] FIG. 1 illustrates a method of joining a cargo roller tray to a support as provided in the related art.
[0013] FIGS. 2A and 2B illustrate a shear fitting with a single lug.
[0014] FIG. 3 illustrates a first embodiment of a shear fitting with two lugs.
[0015] FIG. 4 illustrates a second embodiment of a shear fitting with two lugs.
[0016] FIGS. 5 and 6 illustrate the second embodiment of the shear fitting with two lugs joining a cargo roller tray to a support.
[0017] FIG. 7 illustrates an exemplary aircraft that may contain one of the embodiments illustrated above.
[0018] FIG. 8 illustrates a cross-section of the aircraft illustrated in FIG. 7 .
[0019] Reference will now be made in detail to embodiments of the disclosure, examples of which are illustrated in the accompanying drawings.
DETAILED DESCRIPTION
[0020] The use of the disclosed shear fitting may speed joining a cargo roller tray to a support and may reduce the amount of re-work when assembling pre-drilled components.
[0021] FIG. 1 shows an example from the related art of a cargo roller tray 12 joined to support 14 using fasteners 18 and backing plate 16 . Backing plate 16 is used to spread the load since the tension of fasteners 18 holds the cargo roller tray 12 in position.
[0022] FIG. 2 illustrates one embodiment of a shear fitting that may be used to join a cargo roller tray to a support. Shear fitting 100 may have a back 110 . Typically, back 110 has at least two slots 140 through which shear fitting 100 may be fastened to the support. In some embodiments there may be one slot and in others there may be more than two slots. The number of slots depends on the size and loads on the fasteners. The slots 140 permit the position of the shear fitting 100 to shift. This shift may enable joining the cargo roller tray to the support without the rework associated with holes in the cargo roller tray that do not align with holes in the support.
[0023] The shear fitting 100 may also have a lug 120 with a hole or aperture 130 . The lug projects from the back 110 . In some embodiments the angle between the lug 120 and back 110 may be approximately 90 degrees. In other embodiments the angle between the lug 120 and back 110 may be an acute or obtuse angle.
[0024] The aperture 130 permits the shear fitting to be fastened to the cargo roller tray. In some embodiments, such as illustrated in FIG. 2B , the aperture 130 may be oversized so that the aperture will be capable of receiving a fastener even if the corresponding hole in the cargo roller tray is at its worst case position, but still in tolerance. In other embodiments, aperture 130 may be a slot. In further embodiments the slot in the lug may be located at approximately 90 degrees to the slot(s) 140 in the back 110 .
[0025] FIG. 3 illustrates a second embodiment of shear fitting 200 . In this embodiment the shear fitting 200 has a back 220 and two lugs 210 . Each lug may have an aperture 212 . The apertures are similar to the aperture 130 discussed above.
[0026] Similar to the back 110 discussed above, back 220 may have one or more slots 222 . Slots 222 are similar to slots 140 discussed above.
[0027] FIG. 4 illustrates a modification of the embodiment shown in FIG. 3 . A similar modification may be made to the embodiment shown in FIG. 2 . As illustrated in FIGS. 5 and 6 , this modification may be advantageously used when a portion of a flange 20 on a support beam 14 is removed or the support beam is manufactured with a notch 26 for installation of the shear fitting 300 .
[0028] In the embodiment shown in FIG. 4 the shear fitting 300 includes a web 340 and web extensions 330 . The remaining portions of shear fitting 300 are similar to shear fitting 200 discussed above. The web extensions 330 may each include an aperture 332 . Aperture 332 is configured to permit the shear fitting 300 to be fastened to the flange on a support beam.
[0029] The addition of web 340 and web extensions 330 help mitigate the loss of structural strength caused by the notch 26 in the flange 20 of the support beam 14 in which the shear fitting 300 is installed.
[0030] The shear fittings disclosed herein may be formed from metal using current or future metal forming techniques, e.g., casting, machining, forging, etc. The shear fittings may also be formed from plastic, glass reinforced plastic, composites, etc. using current or future forming techniques, e.g., molding, machining, etc. The materials used may be selected based on the strength and weight requirements of a particular application.
[0031] Referring now to FIG. 7 , a side elevation view of an aircraft 700 having one or more of the disclosed embodiments is shown. With the exception of the embodiments according to the present disclosure, the aircraft 700 typically includes components and subsystems generally known in the pertinent art, and in the interest of brevity, will not be described further. The aircraft 700 generally includes one or more propulsion units 702 that are coupled to wing assemblies 704 , or alternately, to a fuselage 706 or even other portions of the aircraft 700 . Additionally, the aircraft 700 also includes a tail assembly 708 and a landing assembly 710 coupled to the fuselage 706 . In some embodiments the fuselage 706 , tail assembly 708 and nose assembly 712 may form an airframe 714 . In other embodiments the airframe may also include wings 704 .
[0032] The aircraft 700 further includes other systems and subsystems generally required for the proper operation of the aircraft 700 . For example, the aircraft 700 includes a flight control system (not shown in FIG. 7 ), as well as a plurality of other network, electrical, EC, mechanical and electromechanical systems that cooperatively perform a variety of tasks necessary for the operation of the aircraft 700 . Accordingly, the aircraft 700 is generally representative of a commercial passenger or cargo aircraft, which may include, for example, the 737, 747, 757, 767 and 777 commercial aircraft available from The Boeing Company of Chicago, Ill. Although the aircraft 700 shown in FIG. 7 generally shows a commercial aircraft, it is understood that the various embodiments of the present disclosure may also be incorporated into flight vehicles of other types. Examples of such flight vehicles may include manned or even unmanned military aircraft, rotary wing aircraft, ballistic flight vehicles or orbital vehicles, as illustrated more fully in various descriptive volumes, such as Jane's All The World's Aircraft, available from Jane's Information Group, Ltd. of Coulsdon, Surrey, UK. Additionally, those skilled in the art will readily recognize that the various embodiments of the present disclosure may also be incorporated into terrestrial or even marine vehicles.
[0033] As shown in the exemplary aircraft cross section in FIG. 8 , the aircraft 700 may include one or more of the embodiments of the shear fitting 300 , which may be incorporated into various portions of the aircraft 700 . In the embodiment shown in FIG. 8 , an upper support 14 a supports a plurality of cargo roller trays 12 . The roller trays 12 are joined to upper support 14 a with shear fittings 300 . Similarly, a lower support 14 b supports a plurality of cargo roller trays 12 . The cargo roller trays 12 are joined to lower support 14 b with shear fittings 300 . The embodiment shown in FIG. 8 may be used in an airplane 700 configured to carry primarily cargo. In an airplane configured to carry passengers, the upper support beam would be configured to support the passenger cabin instead of the cargo roller trays.
[0034] The above-described shear fittings enable joining cargo roller trays to supports. These and other devices described herein may provide significant improvements over the current state of the art, potentially providing for an assembly process with reduced rework. Although the shear fitting has been described in language specific to structural features and/or methodological acts, it is to be understood that the device defined in the appended claims is not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as exemplary forms of implementing the claimed system and method.
|
Methods of securing a support beam to a structure such as a cargo roller tray or a passenger cabin is achieved using a shear fitting. The shear fitting has a back plate which fastens to the support beam. The shear fitting additionally has parallel lugs which extend from the back plate and fasten to the structure. Web extenders which extend from the shear fitting perpendicular to the lugs may additionally be used to further fasten the support beam to the structure.
| 1
|
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a Continuation-in-Part of U.S. Published patent application Ser. No. 14/484,913 filed on Sep. 12, 2014, which has been abandoned. Thus, this Continuation-in-Part application claims the benefit and the content of the previous application Ser. No. 14/484,913 by specific reference thereto as if fully appearing in the current application.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
Not applicable.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The inventive concept is involved with the use of climbing tree stands for ascending and descending from trees. Most climbing tree stands are comprised of a seat portion and a footstep for placement of the climber's feet. Climbers typically use a body harness, which includes an adjustable strap for wrapping around the trunk of the tree during ascent or descent. The adjustable strap will be referred to as a tree mounting strap for the purposes of this disclosure. The tree mounting strap may be fastened to the climbing tree stand with a bolt, pin, or tensioned buckle for easy adjustment for different tree sizes. The tree mounting strap may also be fastened to an overall body harness worn by the tree climber.
(2) Description of the Related Art, Including Information Disclosed Under 37 CFR 1.97 and 1.98
US # 2012/0018250 A1 (Jan. 26, 2012 discloses a safety strap assembly which is used by a climber for ascending, remaining secured at height and descending from a tree or pole. The safety strap assembly includes a tubular strap; an elastic strap; a stiffening member; a string; a coupling; and a finger-pull. Optionally, an oval chain-link is included. The tubular strap fits around a tree. One end of the tubular strap is connected to an elastic strap. The other end is attachable to the climber. The stiffening member fits within the tubular member. A string extending from two holes in the tubular strap permit the stiffening member to be shifted. The coupling at the free end of the elastic strap connects to the tubular strap in a removable slidable engagement. The finger-pull at that connection breaks away if the climber falls enabling the tubular strap to engage the tree and prevent a fall to the ground.
US # 2009/0236178 A1 (Sep. 24, 2009 is an inventive device featuring a Tree Stand Safety Belt to prevent a wearer/user from falling out of a tree stand used for viewing or hunting wildlife. When properly positioned and securely attached, the device of this invention maintains substantially continuous contact of the wearer's back to a tree trunk. This contact not only provides a physical barrier to moving; that sense of contact also protects its wearer/user from experiencing height disorientation and possibly losing their balance. The device is designed for its wearer to use in either a sitting or standing position.
U.S. Pat. No. 6,206,138 B1 (Mar. 27, 2001 discloses a tree stand safety belt to facilitate climbing of a tree with a climbing tree stand without interfering with climbing movement of the tree stand, and while allowing the belt to be curled up when not in use. The belt body is made of a flexible web of cloth-like material, such as polyester or nylon webbing, and has first and second ends. An attachment device, such as a clip, is provided at the second end, and a loop is typically formed at the first end that allows the second end to pass through it. A stiffening element, such as a chain, is provided at a central portion of the belt between the first and second ends, for example sandwiched between a strip of webbing stitched to the belt body and the belt body itself. During use the belt is connected by a releasable attachment device (such as a spring clamp) to a side support or tree engaging element of the upper frame of a tree stand.
BRIEF SUMMARY OF THE INVENTION
The subject safety device, having a marketing name, “Possum Tail Tree Stand,” is an emergency safety system designed to simplify the task of continually adjusting a tree mounting strap while ascending or descending a tree on a climbing tree stand. The tree mounting strap is a component which is either fastened to the climbing tree stand or to a body harness typically used by a tree climber. The inventive concept is designed to be affixed to a climbing tree stand typically used by an outdoorsman, particularly a hunter. The objective of the device is to facilitate quick use of the tree mounting strap when repositioning the tree mounting strap at different vertical increments on the tree, whether ascending or descending utilizing a climbing tree stand.
The device enables the hunter to remain in his standard tree climbing safety harness from beginning ascent using a climbing tree stand, maintaining a selected tree position, and descending from the tree. The device eliminates the need for the climber to continuously cinch and un-cinch the tree mounting strap while ascending or descending. This is accomplished by means of an adjustable assemblage of metal (or plastic) mounting arms and brackets which, when combined, hold the tree mounting strap within a plurality of retention clasps. Should the hunter begin to fall from the tree through either hunter carelessness or a malfunctioning tree stand, the retention clasps will immediately release, causing the tree mounting strap (to which the hunter's body safety harness is connected) to tighten against the tree trunk. This tightening action will arrest the hunter's fall immediately and prevent serious injury.
BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS
FIG. 1 depicts a general view of the emergency safety system, 1 , and stylized portrayals of a climbing tree stand 3 and the outline of a tree trunk 5 .
FIG. 2 illustrates a view of the upper surface of the left attachment arm 10 .
FIG. 2A depicts a typical wing nut 48 used in various places in the inventive concept.
FIG. 2B is a view of the underside of the elbow 11 of the left attachment arm 10 , further showing the underside of the left front bracket 12 .
FIG. 3 is a top view of the mid-left offset arm 20 , along with the left strap retention clasp 21 .
FIG. 4 presents a view of the upper surface of the outer left offset arm 30 .
FIG. 5 shows a view of the upper surface of the right attachment arm 40 .
FIG 5A illustrates a view of the underside of the elbow 41 of the right attachment arm 40 .
FIG. 6 is a view of the upper surface of the mid-right offset arm 50 .
FIG. 7 presents a view of the upper surface of the outer-right offset arm 60 .
FIG. 8 illustrates a view of a strap retention clasp 51 , looking inward toward the machine screws 57 which secure the clasp.
FIG. 9 is a side view of the strap retention clasp 51 shown in FIG. 8 .
FIG. 10 illustrates the front attachment bracket 12 utilized on the left attachment arm.
FIG. 11 displays a side view of the front attachment bracket 12 of FIG. 10 .
FIG. 12 is a rendering of the tensioned safety washer 17 utilized in fastening the attachment arms to the respective mid-offset arms.
FIG. 13 illustrates the pivot arm bolt 18 used in conjunction with a wing nut 48 .
FIG. 14 shows the manner in which the tree mounting strap 2 fits into the left side and right side retention clasps of the emergency safety system 1 , 1 ( a ), 1 ( b ).
DETAILED DESCRIPTION OF THE INVENTION
The objects, features, and advantages of the concept presented in this application are more readily understood when referring to the accompanying drawings. The drawings, totaling fifteen figures, show the basic components and functions of embodiments and/or methods of use. In the several figures, like reference numbers are used in each figure to correspond to the same component as may be depicted in other figures.
The discussion of the present inventive concept will be initiated with FIG. 1 , which shows that the safety system 1 comprises symmetrical left and right sides. The left side safety harness 1 ( a ) consists of three sequentially-connected, rigid arms, being a left attachment arm 10 , a mid-left offset arm 20 , and an outer left offset arm 30 . Similarly, the right side safety harness 1 ( b ) comprises, in sequence, a right attachment arm 40 , a mid-right offset arm 50 , and an outer right offset arm 60 .
In FIG. 1 , the left side safety harness 1 ( a ) and the right side safety harness 1 ( b ) of the safety system 1 are shown positioned just prior to the preliminary stage of encirclement of a tree trunk 5 . Shown is a portion of a tree mounting strap 2 which may be a component of the typical full body harness worn by tree climbers. A full body harness also typically includes two leg harnesses and a chest harness. The chest harness contains connections for adjusting and locking the tree mounting strap 2 , which strap 2 is then looped around the circumference of a tree trunk. The tree mounting strap 2 is incrementally un-cinched (or unlocked) and re-cinched as the climber ascends a tree. The tree mounting strap 2 may also be a flexible, strengthened material comprising a body harness which is also functional with the safety system 1 .
By way of contrast, as shown in FIG. 1 , when a climber initiates use of the disclosed inventive concept, the tree mounting strap 2 will be inserted in the emergency safety system 1 within special elastomeric retention clasps 21 , 32 , 31 on the mid-left offset arm 20 and outer left offset arm 30 , respectively. The tree mounting strap 2 is further inserted through elastomeric retention clasps 61 , 62 , and 51 on the outer-right offset arm 60 and the mid-right offset arm 50 , respectively.
FIG. 1 illustrates a comprehensive view of the emergency safety system 1 in the configuration of attachment to a stylized climbing tree stand 3 and tree stand seat 4 . A left side brace 7 (or armrest) and a right side brace 6 (or armrest) of the climbing tree stand 3 provide the attachment points for the emergency safety harness 1 ( a ), 1 ( b ). The left attachment arm 10 of the safety system 1 is clamped to the left side brace 6 of the tree stand seat 4 , while the right attachment arm 40 is clamped to the right side brace 7 of the tree stand seat 4 . A left front attachment bracket 12 , a left rear attachment bracket 13 , a right front attachment bracket 42 , and a right rear attachment bracket 43 are used to attach both sides of the emergency safety harness 1 ( a ), 1 ( b ) to the right side brace 6 and the left side brace 7 of the climbing tree stand seat 4 .
FIG. 2 , FIG. 3 , and FIG. 4 display disconnected views of the top surfaces of the three components of the left side safety harness 1 ( a ). The topmost component shown in FIG. 2 is the upper surface of the left attachment arm 10 . A left rear attachment bracket 13 and a left front attachment bracket 12 are affixed to the left attachment arm 10 by means of two machine screws 57 . These two attachment brackets 12 , 13 are designed to clamp the left side harness 1 ( a ) to the left side brace 7 (or arm) of the tree stand seat 4 .
The rightmost end of the left attachment arm 10 comprises an elbow 11 , which protrudes orthogonally outwardly from alignment with the left attachment arm 10 . This protrusion provides for an offset connection of the left attachment arm 10 to the mid-left offset arm 20 (shown in FIG. 3 ). The mid-left offset arm 20 is the center component of the left side safety harness 1 ( a ).
Reviewing more of the details in FIG. 2 , the upper surface of the left attachment arm 10 further includes an aperture 16 , a tensioned safety washer 17 , and the orthogonal elbow 11 . The left front bracket 12 and the left rear bracket 13 are affixed to the left attachment arm 10 by means of a machine screw 57 passing through threads in each bracket 12 , 13 and corresponding threads in the left attachment arm 10 .
FIG. 2B depicts the underside of the elbow 11 and the underside of the left front bracket 12 , which terminates in two flanges 24 . The relative orientation of the two flanges 24 are illustrated more clearly in FIG. 10 and FIG. 11 , which is a view of the left front bracket 12 as seen from the perspective of section line 11 - 11 . A hexagonal head bolt 8 and corresponding nut 9 fasten the two flanges 24 together to securely encompass the left side brace 7 of a typical climbing tree stand seat 3 , as previously shown in FIG. 1 . Similarly, the left rear bracket 13 utilizes the same arrangement of clamping components, being a hexagonal head bolt 8 , nut 9 , and two flanges 24 .
In the arrangement of the left side harness 1 ( a ), the left attachment arm 10 must be attached, at its elbow 11 , to the mid-left offset arm 20 . In referring to FIG. 2B , the manner of fastening the left attachment arm 10 and the mid-left offset arm 20 is shown. Prior to attachment of the left elbow 11 to the mid-left offset arm 20 , a tensioned safety washer 17 is placed in axial alignment with the aperture 16 atop the left attachment arm 10 . An elastomeric bolt 18 (fully shown in FIG. 13 ) is inserted through the undersurface of the elbow 11 . The mid-left offset arm 20 contains a rear aperture 22 corresponding to the aperture 16 of the left attachment arm 10 . Both apertures 16 , 22 , are placed coaxially to allow insertion of the pivot arm elastomeric bolt 18 through the tensioned safety washer 17 and both apertures 16 , 22 . A wing nut 48 is then used to securely tighten the connection of the left elbow 11 to the mid-left offset arm 20 .
An elastomeric left strap retention clasp 21 is shown affixed to the upper surface of the mid-left offset arm 20 . The left strap retention clasp 21 provides a grasp-like conduit through which the tree mounting strap 2 is inserted. The means by which the left strap retention clasp 21 retains the tree mounting strap 2 is illustrated in FIG. 8 and FIG. 9 . FIG. 8 presents a downward-looking view of the right strap retention clasp, while FIG. 9 presents a side view of the right strap retention clasp 51 , as seen from the perspective of section line 9 - 9 . The left strap retention clasp 21 is identical to the elastomeric right strap retention clasp 51 , and the left strap retention clasp 21 operates with the exact same components and in the same manner as the right strap retention clasp 51 .
The third component of the left side safety harness 1 ( a ), is an outer-left offset arm 30 , is shown in FIG. 4 . The outer-left offset arm 30 is connected, via its aperture 33 , in sequence with the forward aperture 23 of the mid-left offset arm 20 by means of a tensioned safety washer 17 , a pivot arm elastomeric bolt 18 , and a wing nut 48 . An left front retention clasp 31 and an elastomeric left rear retention clasp, 32 are affixed to the upper surface of the outer left offset arm 30 to provide a grasp-like conduit for control and positioning, and retention of the tree mounting strap 2 . As discussed before, the means of positioning and grasping of the tree mounting strap 2 is illustrated in both FIG. 8 and FIG. 9 , by virtue of the identical configuration and components of the right strap retention clasp 51 .
The left attachment arm 10 , mid-left attachment arm 20 , and the outer left offset arm 30 are sequentially attached to each other to form the left side harness 1 ( a ).
FIG. 5 , FIG. 6 , and FIG. 7 present views of the top surfaces of the components of the right side harness 1 ( b ). The topmost component shown is the upper surface of the right attachment arm 40 . A rear attachment bracket 43 and a from attachment bracket 42 are affixed to the right attachment arm 40 and are designed to be coupled to the right side brace 7 of the tree stand seat 4 . The leftmost end of the right attachment arm 40 comprises an elbow 41 , which protrudes outwardly from alignment with the side brace 7 of the tree stand seat 4 . This protrusion enables connection of the right attachment arm 40 to the mid-right offset arm 50 , which is the center component shown in FIG. 6 .
Reviewing more of the details shown in FIG. 5 , there is shown a view of the upper surface of the right attachment arm 40 , including a right front bracket 42 , a right rear bracket 43 , an aperture 46 , a tensioned safety washer 17 , and the orthogonal elbow 41 . The right front bracket 42 , and the right rear bracket 43 are permanently affixed to the right attachment arm 40 by means of a machine screw 57 passing through threads in each bracket 42 , 43 . FIG. 5A depicts the underside of the elbow 41 and the underside of the right front bracket 42 , which terminates in two flanges 19 . A hexagonal head bolt 8 and nut 9 fasten the two flanges 24 together to encompass the right side brace 6 of a typical tree stand 3 , as shown in FIG. 1 .
In the arrangement of the right side harness 1 ( b ), the right attachment arm 40 must be attached, at its elbow 41 , to the mid-right offset arm 50 , shown in FIG. 6 . Prior to attachment of the right elbow 41 to the mid-right offset arm 50 , a tensioned safety washer 17 is placed in axial alignment with the aperture 46 atop the right attachment arm. An elastomeric bolt 18 (shown in FIG. 13 ) is then inserted through the undersurface of the elbow 41 . The mid-right offset arm 50 has a rear aperture 52 corresponding to the aperture 46 of the right attachment arm 40 . Both apertures 46 , 52 , are placed coaxially to allow insertion of the pivot arm elastomeric bolt 18 through the tensioned safety washer 17 and both apertures 46 , 52 . A wing nut 48 (shown in FIG. 2A ) is then used to securely tighten the connection of the right elbow 41 to the mid-right offset arm 50 . An elastomeric right strap retention clasp 51 is affixed to the upper surface of the mid-right offset arm 50 , which allows a grasp-like conduit for positioning, and securing the tree mounting strap 2 (illustrated in FIG. 14 ).
The third component of the right side harness 1 ( b ), an outer-right offset arm 60 , is shown in FIG. 7 . The outer-right offset arm 60 is connected, by means of an aperture 63 , in sequence with the forward aperture 53 of the mid-right offset arm 50 by means of a tensioned safety washer 17 , a pivot arm elastomeric bolt 18 , and a wing nut 48 . An elastomeric right front retention clasp 61 and an elastomeric right rear retention clasp, 62 are affixed to the upper surface of the outer right offset arm 60 to allow positioning and retention of the tree mounting strap 2 (not shown).
The right attachment arm 40 , mid-right attachment arm 50 , and the outer left offset arm 60 are sequentially attached to each other to form the right side harness 1 ( b ).
FIG. 8 and FIG. 9 illustrate the right strap retention clasp 51 , with FIG. 9 presenting a cross-sectional view as seen through cutaway line 9 - 9 . The views shown in FIG. 8 and FIG. 9 of the right strap retention clasp 51 also represent the exact structure of the right front retention clasp 61 , and the right rear retention clasp 62 , as well as the three retention clasps, 21 , 31 , and 32 , depicted in FIG. 1 . The details common to all the retention clasps are shown in FIG. 8 , using the right strap retention clasp 51 as a model. The right strap retention clasp 51 comprises a vertical plate 55 forming an integral perpendicular angle to a horizontal plate 56 .
FIG. 9 presents a cross-sectional view of the retention clasp 51 as seen from section line 9 - 9 . An arcuate, tensioned locking plate 54 is fastened to the horizontal plate 56 by means of two machine screws 57 . The two machine screws 57 further continue into the mid-right offset arm 50 and thereby enable the right strap retention clasp 51 to engage and retain the body safety strap 2 .
As described earlier, FIG. 10 and FIG. 11 illustrate contrasting views of the left front bracket 12 . The left front bracket 12 has the same construction and function as the left rear bracket 13 , as well as the right front bracket 42 and the right rear bracket 43 . FIG. 10 depicts an inward looking view of the right front bracket 42 showing a pair of parallel flanges 24 which have axially aligned holes permitting the insertion of a hexagonal head bolt 8 through both flanges 24 and ultimately secured by a nut 9 . FIG. 11 presents a cross-sectional view, of the left front bracket 12 , as seen from section line 11 - 11 . The left front bracket 12 and the left rear bracket 13 serve to clamp the left attachment arm 10 of the safety harness 1 to the left side brace 7 of the stylized tree stand seat 4 shown in FIG. 1 . The same clamping function is accomplished by the right front and rear brackets 42 , 43 .
FIG. 14 shows the manner in which the tree mounting strap 2 fits into the left side retention clasps 21 , 31 , 32 and right side retention clasps 51 , 61 , 62 of the safety harness 1 , 1 ( a ), 1 ( b ). The device eliminates the need for the climber to continuously cinch and un-cinch the tree mounting strap 2 while ascending or descending. This is accomplished by means of the arrangement of retention clasps 21 , 31 , 32 51 , 61 , 62 in a generally circular surrounding of the trunk of the tree 5 . The retention clasps 21 , 31 , 32 , 51 , 61 , 62 are constructed of an elastomeric material, thus should the climber begin to fall from the tree through either accidentally or a malfunctioning climbing tree stand, the retention clasps will immediately bend and release their clasp on the tree mounting strap 2 . This causes the tree mounting strap 2 (to which the hunter's body safety harness is connected) to collapse against the tree trunk 5 . The collapse and tightening action of the tree mounting strap 2 will arrest the hunter's fall immediately and prevent serious injury.
While preferred embodiments of the present inventive concept have been shown and disclosed herein, it is noted that such embodiments are presented by way of example only, and not as a limitation to the scope of the inventive concept. Numerous variations, changes, and substitutions may occur or be suggested to those skilled in the art without departing from the intent and scope of this inventive concept. Such variations, changes, and substitutions may involve other features which are already known per se and which may be used instead of, in combination with, or in addition to features already disclosed herein. This inventive concept is inclusive of such variations, changes, and substitutions, and by no means limited by the wording of the claims presented herein.
|
The inventive concept is a safety device, which is an emergency safety system constructed so as to be clamped to a climbing tree stand typically used by an outdoorsman, particularly a hunter. The objective of the device is to safely expedite the vertical positioning of a tree mounting strap during ascent and/or descent of a tree. This is accomplished by means of symmetrical left and right assemblages of rigid mounting arms, brackets, and retention clasps which, when combined, hold a the tree mounting strap loosely around the circumference of a tree trunk. Should the climber experience an imminent fall from the tree, the arms of the safety device will cause the un-tensioned tree mounting strap (to which the hunter's body safety harness is attached) to collapse against the tree trunk. This tightening action will arrest the fall immediately and prevent serious injury.
| 0
|
This application is a continuation of application Ser. No. 08/615,025, filed Mar. 13, 1996 now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to an arrangement for inclined rolling of tube-shaped or bar-shaped rolling products.
Arrangements for inclined rolling are mainly used for manufacture of seamless tubes, for example perforation of a round insert block and thereby for manufacture of relatively thick walled hollow block, or for stretching of such a hollow block with a reduction of its wall thickness or for expanding a tube loop. Moreover, it is known to use such arrangements for stretching and for cross-section reduction of bar-shaped or in other words massive rolling products.
In conventional arrangements of this type the rolling product is driven in rotation in two rollers which rotate in the same rotary direction and thereby is deformed. For obtaining a controllable displacement of the rolling product in the longitudinal direction the roller axes are arranged relative to the longitudinal axis of the rolling product with a pivoting angle. Therefore, from the peripheral speed of the rollers, a component in the longitudinal direction of the rolling product is produced and the rolling product is moved in a helical movement between the rollers in the longitudinal direction. Such arrangements have two or more driven rollers. Lateral guides between the rollers are needed when only two rollers are provided so that the rolling product remains in the region of the rolling axis does not spring out in a radial direction.
In such arrangements the barrel-shaped rollers are utilized with the roller axes extending parallel to the longitudinal axis of the rolling product. Moreover, it is known to use conical rollers in which the roller axes are inclined to the longitudinal axis of the rolling product. The inclination angle which is obtained here between the roller axes and the longitudinal axis of the rolling product should not be confused with the above mentioned pivoting angle, since the inclination angle alone without turning of the roller axes cannot provide an axial feed of the rolling product.
In the above mentioned arrangement the rolling product rotates about its longitudinal axis, which causes several problems. First of all rolling products of limited length only can be rolled, in order to avoid its unsteady rotary movement and to prevent damages to the rolling product and to the arrangement. -Secondly, expensive guiding devices for the rolling product and for eventually available inner tools are needed. Thirdly, the rolling product throughput and thereby the efficiency of the arrangement is narrowly limited. The rolling product throughput is determined by the feeding speed, and it is produced from the peripheral speed of the rolling product and the magnitude of the pivoting angle. Since the pivoting angle cannot exceed a predetermined magnitude because otherwise the surface of the rolling product becomes non-uniform and in particular wavy, the rolling product throughput is increased only by an increase in the peripheral speed. However, this increases the rotary speed of the rolling product as well which leads to an unsteady running resulting in damages to the rolling product, disturbances in the machinery and increased wear. Moreover, the rolling product during rolling must be accelerated stronger in view of the higher rotary speed of the rolling, which leads to sliding of the rollers and thereby to gripping problems. Fourthly, the rolling product which rotates about its longitudinal axis prevents a continuous finishing rolling in longitudinal rolling stands arranged at a short distance.
In view of the above disadvantages the kinematic principle of the inclined rolling was reversed. In particular it has been changed so that the rollers rotate not only around their roller axes, but also around the longitudinal axis of the rolling product. As a result the rolling product must not be brought to rotation about its longitudinal axis. The rollers roll in a planetary movement on and around the rolling product.
Such an arrangement is disclosed for example in U.S. Pat. No. 1,368,413. Here the rollers are supported with their roller shafts in a rotary housing which is driven through a toothed rim and a pinion. The shafts which drive the rollers has ends which face away from the rollers and are provided with toothed gears rolling on a sun gear as in a planetary transmission. The sun gear is also driven. With a corresponding determination of the rotary speeds of the rollers and the rotatable housing it is possible to roll the rollers on the rolling product without driving it in rotation. The rollers of this known type are barrel shaped and their roller axes extend in planes which are parallel to the longitudinal axis of the rolling product. The roller axes however are turned by an angle relative to the longitudinal axis of the rolling product in these planes, and thereby the feeding movement of the rolling product is produced. Also, the axes of the planetary gears extend with this angle relative to the longitudinal axis of the rolling product, but they are located in a plane which includes the longitudinal axis of the rolling product. The roller drive shafts between the planetary gears and the rollers are provided at their ends with joint couplings. In order to maintain the bending angle of the joint couplings not too great, the roller drive shafts are relatively long. This however leads to a long construction of the rotatable housing. Moreover, the long roller drive shafts are subjected during rotation of the rotatable housing to centrifugal forces and gyroscopic moments, which limits the rotary speed of the housing.
The German document DE-OS 16 02 153 shows in FIG. 1 an arrangement which in principle has the above described features. FIG. 2 however illustrates another construction. Here the rollers are conical and the roller axes extend under an inclination angle relative to the longitudinal axis of the rolling product. The rollers are supported floatingly in heads which are arranged at the end side of a rotor housing rotating around the longitudinal axis of the rolling product and driven through a toothed rim. The rollers are driven through several toothed gears or toothed gear drive steps arranged radially from the longitudinal axis of the rolling product one after the other. The first toothed gear engages a sun gear and rolls on it by the rotary movement of the rotor housing in which it is supported. In U.S. Pat. No. 1,368,413 the sun gear in this known construction is rotated by a special drive. The rotary speed of the sun gear and the rotary speed of the rotor housing can be selected so that the rollers roll on the rolling product without driving it in rotation. With the above mentioned inclination of the roller axes relative to the longitudinal axis of the rolling product no rolling product feed can be obtained. The feed is produced by a pivoting of the head which is arranged turnably around a bevel gear axis on the rotor housing. The pivoting angle produced in this manner is not shown in FIG. 2 of this reference. This construction has three rollers and is provided both for tube-shaped and for bar-shaped rolling products.
The latter construction is very expensive because of its roller drive. The toothed gears of the roller drive staggered radially outwardly from the longitudinal axis of the rolling product operates so that the rotating rotor housing has a huge outer diameter which, depending on the cross-sectional size of the rolling product, amounts to approximately 3-5 meter. The rollers, the roller shaft, their bearings and the head which has the drive gears are arranged on this big rotor housing, so that extraordinarily high rotating masses are produced in the case of great outer diameters. Because of the thusly generated centrifugal forces, the rotary speed of the rotor housing with the head is very limited and therefore the feeding speed of the rolling product is also limited. As a result, the throughput of the rolling product per time unit and therefore the efficiency is low. Since the head as well as the rotor housing have great sizes and there is a relatively great distance of the pivoting axis of the head from the corresponding roller axes, an exact adjustment and maintenance of the roller position is difficult, and different springing of the rollers under load must be taken into consideration. Because the radially outwardly staggered gear teeth is the bevel gear drive of the rollers located far outside and therefor it requires a very steep inclination of the roller axes relative to the longitudinal axis of the rolling product, in order that the axial length of the arrangement as well as the rotor housing and the heads become greater. An inclination of the roller axes relative to the longitudinal axis of the rolling product is generally advantageous. However, when this inclination is too steep rollers are produced with specially pronounced or in other words flat conical shape with a strong reduction of the roller diameter, especially in the region of the roller tip. The smoothing zone and the rounding zone of the rollers is located where the strong diameter reduction acts in a specially negative way, causing undesired twisting of the rolling product during rolling. This danger is caused in the known construction by the necessary steep inclination of the roller axes and thereby required flat conical shape of the rollers.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an arrangement for inclined rolling of tube-shaped and bar-shaped rolling products, with two or more driven rollers which are rotatable about the longitudinal axis of the rolling product and have roller axes extending inclinedly under an inclination angle relative to the longitudinal axis of the rolling product.
It is an object of the present invention to provide an arrangement of this type which avoids the disadvantages of the prior art and has smaller dimensions with increased efficiency.
In keeping with these objects and with others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in an arrangement of the above mentioned type in which for producing a rolling product feed the roller axes are inclined in such planes which extend, when considered in or opposite to the longitudinal axis of the rolling product, with a radial distance parallel near the longitudinal axis of the rolling product, and the rollers are driven by a sun wheel through a drive gear which has an axis-offset bevel gear toothing, engages with the sun gear and surrounds the corresponding roller axes.
In the arrangement in accordance with the present invention, the rolling product feed can be produced not only as in the known constructions with a turning of the rollers and the roller axes under a pivoting angle relative to the longitudinal axis of the rolling product, but such a turning can be dispensed when the roller axes extend correspondingly within a plane arranged at a radial distance from and parallel to the longitudinal axis of the rolling product as considered in or opposite to the longitudinal axis of the rolling product. This new arrangement of the roller axes produces however the desired rolling product feed only when the roller axes are inclined within the above mentioned planes under an inclination angle relative to the longitudinal axis of the rolling product, or in other words the rollers are formed substantially cone-shaped or truncated cone-shaped. When the rollers are barrel-shaped or cylindrical and their roller axes have no inclination angle, no rolling product feed is produced without the pivoting angle. When substantially conical rollers and thereby roller axes are utilized instead and they are inclined under an inclination angle relative to the longitudinal axis of the rolling product, the additional utilization of a pivoting angle can be dispensed with as available in the above mentioned constructions with driving of the rolling product in the longitudinal direction.
In the inventive arrangement, when considered in or against the longitudinal axis of the rolling product, the laterally offset, parallel arrangement of the roller axes relative to the longitudinal axis of the rolling product with an inclination angle which is not seen with this view, a substantially compact construction of the arrangement is provided. The reason is that it is possible to arrange each roller axes or roller shaft in association with a drive gear for the rollers, which engages directly with the sun gear and thereby rolls on it. Therefore, all joint shafts and joint couplings or toothed gears located between the sun gear and the roller shafts are dispensed with. With the laterally parallel offset of the roller axes in the construction having the drive gears and the sun gear it is however necessary to use an axis-offset bevel gear toothing which is known from other solutions. Since in such construction numerous parts are eliminated, the masses rotating about the longitudinal axis of the rolling product are reduced, the distance between the remaining parts from the longitudinal axis of the rolling product is small, and the centrifugal forces are substantially reduced. Therefore the arrangement can be not only substantially smaller for the same cross-section of the rolling product, but also the rotation can be performed with substantially higher rotary speed about the longitudinal axis of the rolling product and as a result a higher throughput of the rolling product or in other words a substantially improved efficiency is obtained. In the inventive solution the inclination angle between the roller axes and the longitudinal axis of the rolling product is also relatively small. This not only makes the drive gears and therefore the whole arrangement small, but also leads to a less pronounced conical shape of the rollers or in other words to a more cylindrical roller shape. With this roller shape the roller diameter decreases less, especially in the region of the smoothing zone and the rounding zone. Therefore the twisting of the rolling product is avoided, which otherwise easily occurs especially in the case of rolling thin walled tubes in this region.
In accordance with an advantageous embodiment of the present invention, the drive gears engaging with the sun gear are arranged fixedly and directly on the shafts which carry the rollers. In this construction an adjustment of the radial distance of the roller or the roller axes from the longitudinal axis of the rolling product is not possible, so that feed of the rolling product remains the same. When in this embodiment the drive gears are also arranged non-displaceably in the axial direction on the shaft carrying the rollers, then in view of the fact that it is necessary to maintain the engagement of the toothed gears, also an axial displacement of the shafts which carry the rollers and also the axial displacement of the rollers is not possible. When differently thick inserts are arranged between the rollers and the shaft which carry the rollers, then in this embodiment the rollers can be adjusted in the axial direction and therefore in view of their inclination relative to the axis of the roller product the diameter of the rolling product can be also adjusted. During rolling of tubes, the wall thickness of the rolling product can be adjusted by corresponding selection of the diameter of the inwardly located tool to the desired size. It is generally faster and more accurate than a roller adjustment and avoids an undesirable change of the cylindrical smoothing caliber shape. Moreover, in this simple embodiment an especially compact arrangement with a high stability against the occurring roller forces is provided.
It is also possible to form the drive gears which engage with the sun gears so that in their hub region a hollow toothing is arranged, and an outer toothing of a shaft which carries a respective roller engages in the hollow toothing. The shaft can be supported in a rotatable eccentric bushing and adjustable transversely to the drive gear and to the longitudinal axis of the rolling product. In this arrangement the radial distance of the roller axes from the longitudinal axis of the rolling product can be adjusted and thereby the feed of the rolling product can be changed.
In accordance with a further advantageous embodiment of the invention, the rollers are adjustable in direction of their roller axes. This can be provided first of all by an axially displaceable and preferably steplessly adjustable support of the shafts which carry the rollers. In this manner the smallest diameter described jointly by all rollers can be changed, and thereby the finishing diameter of the rolling product can be changed as well. The adjustability of the shafts and the rollers in the longitudinal direction of the roller axes can be also combined with the previously mentioned transverse adjustment of the roller axes, so that in such an arrangement both the outer diameter of the rolling product and the feed of the rolling product can be changed. On the other hand, an adjustment of the rollers in direction of their roller axes can be performed in the above described manner by inserts. The produced rollers can be brought to a desired position by the use of other inserts, so as to obtain a high accuracy and reproducibility of the caliber adjustment.
The above described constructions and approaches to the axial and radial adjustment of the rollers and their roller shafts can be also utilized for other structural solutions.
In accordance with an especially advantageous embodiment of the invention, all four driven rollers are provided. The use of four instead of frequently utilized three rollers has the advantage that the cross-section of the rolling product can be enclosed narrower by the rollers. This leads especially during rolling of thin walled tubes, to a smaller expansion of the rolling product between the rollers and thereby to a reduction of additional bending loads and sliding of the workpiece. Moreover, with the four rollers, the roller diameter which leads to the maximum possible embracing of the rolling product is smaller than in the case of three rollers. Smaller roller diameters provide for a substantial advantage of smaller rolling moments. Therefore, all parts of the roller drive and the rotor can be smaller and lighter and the arrangement as a whole can be more compact. The use of the rollers with the smaller diameter in which the reduction of the roller diameter in the region of the smoothing zone and the rounding zone therefore the problem of the rolling product sliding is grave, is not problematic in the inventive arrangement since it utilizes an especially flat inclination angle which acts in a compensating manner.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, 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
FIGS. 1-3 are views showing an arrangement for inclined rolling of tube-shaped and bar-shaped rolling products correspondingly on a front view, a side view and a plan view;
FIG. 4 is a view showing the inventive arrangement without a roller adjustment in a schematic illustration;
FIG. 5 is a view showing the inventive arrangement with an axial roller adjustment; and
FIG. 6 is a view showing the inventive arrangement with an axial and radial roller adjustment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The cross-sectional surfaces of a rolling product is identified with reference numeral 1 on a front view of FIG. 1 . It is formed as a massive bar. The rolling product can however be also formed as a tube or a tube loop, and an inner tool such as for example a mandrel rod can be located in it. The rolling product 1 is formed by several rollers 2 which surround the rolling product 1 . In FIGS. 1-3 only one roller 2 is shown for the clarify of illustration of the inventive features. The rollers 2 gyrate in a planetary fashion around an axis 3 of the rolling product extending perpendicular to the plane of the drawing in FIG. 1 . The rollers 2 rotate their roller axes 4 and roll on an outer surface of the rolling product 1 . The rollers 2 in the shown example are substantially conical. They have the shape of two frusto-cones arranged over one another and having differently inclined peripheral surfaces. It is especially clearly shown on the side view of FIG. 2, in which it can be seen that the roller axes 4 extend under an inclination angle relative to the longitudinal axis 3 of the rolling product. This known inclination angle does not cause any axial feed of the rolling product 1 when the roller axes 4 and longitudinal axis 3 of the rolling product are located in one plane. The additionally utilized pivoting angle which is provided in the known constructions is not provided in the inventive arrangement, as can be seen in particular in FIG. 1 . On the front view of this Figure when seen in or against the longitudinal axis 3 of the rolling product, it can be seen that the plane in which the roller axes 4 extend inclinedly is located parallel to the longitudinal axis 3 of the rolling product at a radial distance E from it. From the configuration of a contact point 5 between the roller 2 and the rolling product 1 , it can be seen that the roller peripheral speed 6 produces a component 7 in the feeding direction of the rolling product 1 . Also, from the plan view of FIG. 3 the component 7 which causes the feed can be recognized as well.
FIG. 4 shows an arrangement partially in a longitudinal section in which the rollers 2 and their roller axes 4 are arranged in the inventive manner. Two rollers 2 are visible on these drawings while two further rollers 2 , forming together for example four rollers, are located in a foreground and in a background and therefore not shown for more clear illustration of the other two rollers 2 .
The rollers 2 are driven by a motor. The drive is performed through shafts 8 which carry the rollers. Drive gears 9 are arranged directly on the shafts 8 and fixedly connected with them for joint rotation. The drive gears 9 engage with a sun gear 10 which surrounds the rolling product 1 . For this purpose, an axis-offset bevel gear toothing 11 is used by reason of the distance E in FIG. 1 . The sun gear 10 has a longitudinally extending drive bushing 12 which fixedly connects the sun gear 10 with a toothed gear 13 for joint rotation, and the toothed gear 13 is controllably driven through a pinion 49 from the not shown motor. The shafts 8 which carry the rollers 2 are rotatably supported in a rotor 14 which in turn rotates around the longitudinal axis 3 of the rolling product, since it is rotatably supported in a housing 15 . The rotor 14 is driven by a further pinion 16 which engages in a toothed rim 17 of the rotor 14 and is also separably driven by a not shown motor.
FIG. 5 shows a support for only one roller 2 on an enlarged scale, while the arrangement is formed substantially as shown in FIG. 4 . Same or similar parts are identified here with the same reference numerals. The construction of FIG. 5 makes possible through an axial adjustment of the rollers 2 by adjusting the shafts 8 , while the construction of FIG. 4 makes possible an axial adjustment of the rollers 2 only by differently thick inserts between the rollers 2 and the shafts 8 . The rollers 2 are tensioned each by a pulling anchor 18 in an axial direction fixedly with its shaft 8 , which pulling anchor is arranged in a central longitudinal opening of the shaft 8 . Radial bearings 19 and 20 provide a limited but sufficient axial displacement of the shaft 8 . The drive gear 9 is screwed in this construction with a bearing bushing 21 which is supported through an axial bearing 22 and the radial bearing 23 rotatably and axially non-displaceably in the rotor 14 . The rotor, in turn, is supported through a bearing 24 in the housing 15 . The rotor 14 has bushings 25 and 26 which surround both the shaft 8 as well as the bearing bushing 21 which surrounds the same. The bushings 25 and 26 are screwed with a rotor 14 and rotate with it around the longitudinal axis 3 of the rolling product. In other aspects, the bushings 25 and 26 are stationary. The same is true for the drive gear 9 and the bearing bushing 21 . The shaft 8 and also the roller 2 as well as the pulling anchor 18 perform the rotary movement around the longitudinal axis 3 of the rolling product. However, with these parts a displaceable relative to the remaining parts in particular relative to the bushings 25 and 26 in or against the direction of the roller axes 4 . The rotary fixed coupling between the bearing bushings 21 and the shaft 8 with the roller 2 is produced through a coupling bushing 27 , which engages in a toothing 28 of the bearing bushing 21 and also in a toothing 29 of the shaft 8 . The toothings 28 and 29 allow a relative displacement in the longitudinal direction. FIG. 5 shows this situation during the rolling operation, in which the drive rotary movement is transmitted from the drive gear 9 through the bearing bushing 21 , the coupling bushing 27 and the shaft 8 to the roller 2 .
When during adjustment of the arrangement the roller 2 must be displaced in the axial direction, the rotor 14 is turned to an adjusting position. A working cylinder 30 displaces by its bushing 31 a plate 32 against the action of a pressure spring 33 in an axial direction, so that the pressure pin 34 engages in a third toothing 35 of the coupling bushing 27 and couples it fixedly with the rotor 14 . The pressure pin 34 presses the coupling bushing 27 further toward the roller 2 until the toothing 28 of the bearing bushing 21 is no longer in engagement with the coupling bushing 27 , which is maintained however for the longer toothing 29 of the shaft 8 . When the sun gear 10 is slowly rotated by a separate drive, then with the stationary rotor drive only the drive gear 9 with the bearing bushing 21 is rotated. A thread 36 between the shaft 8 and the bearing bushing 21 operates so that the shaft 8 is displaced in direction of the roller axis 4 with it the roller 2 is displaced as well. When its position is adjusted and the sun gear 10 is stopped, the working cylinder 30 is relieved from the pressure medium pressure and the plate 32 is released. The pressure spring 33 displaces the pressure pin 34 and a further pressure spring 37 displaces the coupling bushing 27 again to the operating position. In this position the toothing 28 is engaged and the shaft 8 as well as the roller 2 is driven again. The above described operation is true for each roller 2 and its support.
FIG. 6 shows a substantially different construction of the arrangement. The parts which are identical or similar are identified with the same reference numerals as in FIG. 5, also, when the construction of these parts is somewhat different. For example the toothing 28 of the bearing bushing 21 in FIG. 6 is substantially longer than the toothing 29 of the shaft 8 . The toothing 29 is as long as the engaging toothing on the coupling sleeve 27 . When it is moved by the working cylinder 30 in direction of the roller 2 , toothing 29 disengages faster in view of the shortened length. Then the shaft 8 and the roller 2 with it is rotatable by the sun gear 10 and the drive gear 9 relative to the fixedly held bearing bushing 21 and is displaceable because of the thread 36 in the axial direction. The bearing bushing 21 is held non-rotatably by the non-rotatably arranged and formed working cylinder 30 through its bushing 31 , a toothing 45 , the plate 32 , the coupling bushing 27 screwed with it, and the toothing 28 .
In the construction of FIG. 6 the other differences include the fact that the shaft 8 and the roller 2 with it is adjustable transversely to the longitudinal axis 3 of the rolling product. The drive gear 9 is rotatably supported in a connecting member 44 of the rotor 14 with a fixed bearing 38 and a movable bearing 39 and remains therefore in a correct engagement with the sun gear 10 . The drive gear 9 is provided in the hub region with a hollow toothing 40 in which an outer toothing 41 engages. This is however only on a limited part of the periphery as identified with 42 , since the outer toothing 41 of the shaft 8 has a substantially smaller diameter than the hollow toothing 40 . The adjustment path of the shaft 8 is produced in this way. The shaft is supported in an eccentric bushing 43 which is rotatable and fixable in the rotor 14 , and the bushing 25 in FIG. 6 is formed as such an eccentric bush. A timing of the eccentric bushings 25 and 43 in which the radial bearings 23 and 20 are located leads to a transverse displacement of the shaft 8 and the roller 2 . The turning of both eccentric bushings is performed synchronously by the connecting member 44 coupled to them, after the screws 46 are loosened.
In the examples which are described above and shown in the drawings, the throughgoing direction of the rolling product is selected so that a converging arrangement of the rollers is provided. It is also however possible to change the throughgoing direction of the rolling product so that the roller arrangement is diverging. The latter is produced when the arrangement is utilized for example as an expanding roller stand for tubes.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.
While the invention has been illustrated and described as embodied in an arrangement for inclined rolling of tube-shaped or bar-shaped rolling products, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.
What is claimed as new and desired to be protected by letters patent is set forth in the appended claims.
|
An arrangement for inclined rolling of tube-shaped or bar-shaped rolling products comprises at least two rollers adapted to receive therebetween a rolling product so as to determine a longitudinal axis of the rolling product, the rollers are driveable and are rotatable about said longitudinal axis. The rollers have roller axes inclined at an inclination angle relative to the longitudinal axis, the roller axes being inclined in such a plane which, when considered in or against the longitudinal axis, extends parallel to the longitudinal axis at a radial distance from it, and a driving unit for driving the rollers. The driving unit includes a sun gear and drive gears provided with an axis-offset bevel gear toothing and surrounding a respective one of the roller axes, the drive gears engaging with the sun gear so that the rollers are driven by the sun gear through the drive gears.
| 1
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 62/347,432, filed Jun. 8, 2016, the disclosure of which is incorporated by reference herein.
FIELD AND BACKGROUND OF THE INVENTION
[0002] The present disclosure relates to antiseptics. More particularly, it relates to antiseptics used on the teats and udders of dairy animals, such as dairy cows.
[0003] Microorganisms such as bacterial and fungal species can cause a serious infection in mammary glands of dairy animals, such as cows. This infection, which is commonly known as mastitis, has a significant economic impact on dairy farmers worldwide. Estimates suggest that there is a loss in income of from $125 to $200 per cow per year in the United States due to mastitis with an overall loss of 1.8 billion dollars annually. In other regions, such as Europe, the overall loss is 1.4 billion dollars per annum. The overall global loss per year is estimated at four billion to five billion dollars.
[0004] Dairy animals live in a challenging environment where they and their external milk-producing organs can be subjected to high levels of organic contaminants, which may compromise the ability of topical antiseptics to kill harmful microorganisms. The organic contaminants that the milk producing organs of these animals might be exposed to include soil, manure produced by the animals, and the bedding in which the animals lie, which may itself be composed of organic material such as wood chips, straw, or recycled manure.
[0005] One method that has been adopted to help prevent the incidence of mastitis in dairy cows and other dairy animals is the use of topical antiseptics, known in the industry as teat dips, teat (or udder) washes, teat wipes, foams, or sprays. These topical antiseptics are applied to the udder and especially the teats of dairy animals as a part of a general dairy hygiene regime. The antiseptics are designed to kill or debilitate the harmful microorganisms that can cause mastitis while on the skin of the teats and udder before they can be allowed to migrate or otherwise be propelled up into the teat canal where they can infect the mammary gland. Topical antiseptics are generally applied before and/or after every milking, which can number up to four or more times per day in some dairy harvesting facilities.
[0006] During the time just prior to milking and the time immediately after milking, teats frequently leak or drip milk, thereby contributing organic material that may mix with topical antiseptic when applied at the teat end. As a consequence, topical antiseptics need to be non-toxic both to the animals and to the humans applying them to the animals, as well as consumers of milk from the animals.
[0007] Additionally, after milking, the teats are frequently deflated from the loss of milk and are therefore wrinkled, which may block adequate penetration by topical antiseptics to those areas of the skin surface that are more sequestered. Furthermore, the teats themselves may be in a condition not conducive to topical antisepsis, such as when they may be injured, chapped, or otherwise in an unhealthy condition due to harsh weather conditions or the rigors of frequent milking, which may compromise normal teat skin defenses and harbor microorganisms.
[0008] Microorganisms also may be harbored near the orifice at the teat ends because of a condition known as hyperkeratosis, where the keratin naturally found within the teat canal is caused to extend from the teat orifice because of improper milker unit settings, malfunctions of the milking machinery, or by over-milking which occurs when the milking unit claw is left on for too long during milking. Further, due to the presence of organic material and less than optimal conditions for the teat skin and teat ends, any antimicrobial utilized for teat antisepsis must be chemically potent to be effective. A negative aspect to potency is that it might necessitate the use of chemically-strong oxidizers such as iodine and chlorine or compounds that are at a low (acidic) pH such as chlorine dioxide or mid-chain carboxylic (fatty) acids, which can be and frequently are irritating to the animal's skin, especially with frequent and repeated use over extended periods of time. It has been an ongoing challenge in the dairy industry to find antiseptics that fulfill both of the requirements for effectiveness and gentleness.
[0009] The antiseptics should not be irritating to the skin of the animal to which they are applied nor should they be harmful to consumers of milk contaminated by the antiseptics. Consequently, there is a need for antiseptics that are not only effective in killing or debilitating the microorganisms that cause mastitis, but that are also gentle to the skin and non-toxic to the consumers of the milk produced by the animals, and also the environment in which the animals are located should the chemicals get into the waste stream. Currently, some teat antiseptics include potent chemical antimicrobials having halogens, such as iodine or chlorine, as well as other chlorinated compounds such as chlorine dioxide that, at high enough concentrations for bactericidal efficacy, can in some cases produce potentially harmful residues in the milk. In addition, since many of these germicides work as oxidizing agents, they can and frequently do cause irritation to skin of the animals.
[0010] Other common germicides used in teat antiseptis such as biguanides including chlorhexidine and cationic agents such as quaternary ammonium salts at high enough concentrations for efficacy, can be harmful to skin tissue after frequent and long-term use, and are considered by many in the art not to be broad-spectrum enough since some microorganisms are known to survive in these germicides. Other antimicrobial chemicals, including alpha-hydroxy acids such as lactic acid and glycolic acid are not considered potent enough by themselves for most teat antiseptic applications. Others, including alcohols such as ethanol and n-propanol can act as de-fatting agents to skin tissue and therefore be irritating, whereas other germicides, including such oxidizing compounds as peroxides and peracids, can also be irritating to skin tissue.
[0011] As a consequence, there is a need in the art for an effective teat antiseptic that is also non-irritating to the skin of the milk-producing animal.
SUMMARY OF THE INVENTION
[0012] The present invention is directed to compositions and methods for reducing the incidence of mastitis in dairy animals. An exemplary method for reducing the incidence of mastitis in dairy animals in accordance with the present invention includes the steps of: topically applying an antimicrobial composition onto the teats or udder of the animal, the composition having: a first component having from about 2.0% to about 20.0% by weight of the total composition of an amine oxide surfactant 0.01% to about 0.5% by weight of the total composition of one or more oxidizing agents such as hydrogen peroxide, peracids, alpha hydroxyl acids, or halogens. The second component can also include short-chained antiseptic alcohols or cationic agents such as quaternary ammonium compounds or glycol ethers.
[0013] The amine oxide can include N-Alkyl (C10-18) dimethylamine oxide, such as decyl dimethylamine oxide, lauryl (dodecyl) dimethylamine oxide or myristyl dimethyl amine oxide, or combinations thereof. The second component can include hydrogen peroxide, peroxyacetic acid, lactic acid, glycolic acid, tartaric acid, citric acid, mandelic acid, malic acid, or a halogen selected from the group comprising iodine derivatives, chlorine derivatives, bromine derivatives, or combinations thereof.
[0014] Another exemplary embodiment of a method for reducing the incidence of mastitis in dairy animals includes the steps of: topically applying an antimicrobial composition to a teat or udder of the animal where the antimicrobial composition includes: a first component having from about 2.0% to about 20.0% by weight of composition of one or more amine oxide surfactants; and a second component having from about 0.5% to about 20.0% by weight of composition of a germicide having one or more cationic agents, alcohols, or glycol ethers or combinations thereof. The second component can also include: a quaternary ammonium compound; didecyl dimethyl ammonium chloride such as chloride or monoalkyl dimethyl benzyl ammonium salts or monoalkyl dimethyl ammonium salts or heteroaromatic ammonium salts, or bis-quaternary ammonium salts; or phenoxyethanol. The second component can also include n-propanol, iso-propanol, ethanol, benzyl alcohol, methylene blue, or combinations thereof.
[0015] The invention is also directed to a method for reducing the incidence of mastitis in milk-producing animals, the method including the steps of: topically applying an antimicrobial composition to the teat or udder of the animal wherein the antimicrobial composition includes: a first component comprising from about 2.0% to about 20.0% by weight of composition of one or more amine oxide surfactants; and a second component having from about 0.5% to about 20.0% by weight of composition of a germicide comprising one or more mid-chain carboxylic acids. The mid-chain carboxylic acid can be selected from the group including: hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, and combinations thereof.
[0016] Another method for reducing the incidence of mastitis in milk-producing animals in accordance with the present invention includes the steps of: topically applying an antimicrobial composition to the teat or udder of the animal, wherein the antimicrobial composition includes: a first component having from about 2.0% to about 20.0% by weight of the composition of one or more amine oxide surfactants; and a second component having from about 0.01% to about 0.5% by weight the composition of a germicide comprising: a peracid and an alpha hydroxyl acid; an alpha hydroxyl acid; a glycol ether; and combinations thereof.
[0017] Yet another method for reducing the incidence of mastitis in dairy animals includes the steps of: topically applying an antimicrobial composition to the teat or udder of the animal wherein the antimicrobial composition comprises: a first component comprising from about 2.0% to about 20.0% by weight of the composition of an amine oxide surfactant; and a second component comprising from about 0.01% to about 0.5% by weight of the composition of a germicide comprising a mid-chain carboxylic acid.
[0018] The second component can include: a mid-chain carboxylic acid selected from the group: hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, and combinations thereof.
[0019] These and other features and advantages of various embodiments of compositions and methods according to this invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of various compositions and methods of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] A topical germicidal composition in accordance with the present invention utilizes a class of surfactants known as amine oxides, in combination with germicidal ingredients to enhance the ability of those formulations to kill or debilitate microorganisms, such as bacterial and fungal species that can cause mastitis in dairy animals. The present invention minimizes teat irritation, toxicity, and residues while also acting as an effective agent for killing harmful mastitis-causing microbial pathogens on the teat and udder of dairy animals.
[0021] Amine oxides are amphoteric surfactants, which can be produced by the reaction of a tertiary amine with peroxide or peracetic acid. They are of the nomenclature where the functional group is R 3 N + —O − , such as, for example:
[0000]
[0000] The methyl groups shown in the exemplary formula may be replaced with other R chains.
[0022] Furthermore, amine oxides are cationic when in an acidic medium, whereas they will react non-ionically in neutral or alkaline solutions. Examples of amine oxides of the dimethylamine oxide moiety include decyl dimethylamine oxide where the R group=10 (such as Barlox® 10S), lauryl dimethyl amine oxide where the R group=12 (such as Barlox® 12) and myristyl dimethyl amine oxide (such as Barlox® 14) where the R group=12. Other amine oxides that may also be included in the composition are cocamidopropylamine oxide, hexadecyl dimethylamine oxide, octyldecyl dimethyl amine oxide, lauryl/myristal, amidopropyl amine oxide, lauramine oxide, myristamine oxide, tallowamidopropyl dimethylamine oxide, bis (2-hydroxyethyl) cocamine admidopropyloxide, dimethyl (hydrogenated tallow) amine oxide, bis (2-hydroxyethyl) tallowamine oxide, octyl dimethyl amine oxide, coco dimethyl amine oxide, alkyl (C12-C18) dimethyl amine oxide, alkyl (C12-C16) dimethyl amine oxide, alkyl (C12-C14) dimethyl amine oxide, stearyl dimethyl amine oxide, tertiary alkyl amine oxide, alkyl dihydroxyl ethyl amine oxide, alkyl dihydroxyl ethyl lauramine oxide, alkyl dihydroxyl ethyl stearamine oxide, alkyl dihydroxyl ethyl tallowamine oxide, 2,2′-(Z)-octadec-9-en-1-ylimino) bisethanol amine oxide, cocoylamido propyldimethyl amino oxide, coconut amido alkyl amine oxide, cocamide propylamine oxide, dihydroxyethyl amine oxide, N-methylmorpholine amine oxide, pyridine amine oxide or combinations of two or more of the above amine oxides. Additional amine oxides that may be included in the composition are those such as isoalkyl dimethyl amine oxides and alkyl oxypropylamine or ether amine oxides (Tomamine AO-405, Tomamine AO-455, Tomamine AO-14-2, Tomamine AO-728 special).
[0023] Amine oxides can enhance the efficacy of some antimicrobials, including those mentioned above and can include: peroxides such as hydrogen peroxide and alpha-hydroxy acids such as lactic acid, formic acid, citric acid, mandelic acid, and glycolic acid; and quaternary ammonium compounds such as didecyl dimethyl ammonium chloride (such as Bardac® 2280) and glycol ethers such as phenoxyethanol.
[0024] Other antimicrobial components that may react with amine oxides so that they produce a synergistic or enhanced ability to kill microorganisms include straight chain alcohols such as ethanol, propanol and isopropyl alcohol. The composition may also include certain phosphate esters such as Ethoxylated Alcohols Phosphate Esters which may act synergistically with such component as amine oxides and hydrogen peroxide. Other components that may be used in the composition are certain dyes or stains such as methylene blue, which itself has antimicrobial characteristics, but can also act synergistically with amine oxides and hydrogen peroxide together.
[0025] Yet another antimicrobial chemical component that may react with amine oxides to increase antimicrobial efficacy, with or without hydrogen peroxide, are mid-chain fatty acids such as heptanoic acid, octanoic acid, nonanoic acid, and decanoic acid.
[0026] Amine oxides are not generally considered to be antimicrobials by chemists and engineers and others in the dairy industry, but the present invention demonstrates that when amine oxides are added to certain antimicrobial chemicals, such as those identified herein, there is a significant enhancement in bactericidal efficacy. The data in laboratory bactericidal efficacy tests demonstrate an increase in bactericidal efficacy when amine oxides are added to formulations containing one or more of the various above mentioned antimicrobial chemicals against such mastitis-causing pathogens as Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus agalactiae, Streptococcus uberis and Pseudomonas aeruginosa . For example, one of the most resistant mastitis pathogens against oxidizing germicides, Staph aureus , was used to test the bactericidal efficacy of a hydrogen peroxide base formula with varying amounts of an amine oxide (lauryl dimethyl amine oxide or tradename Barlox® 12). (See: Table 1.) This showed an increasing kill rate as the amount of the amine oxide increased from 0% to 5% when mixed with a peroxide base, for example.
[0000]
TABLE 1
Treatment— Staph. aureus
%
ATCC # 6538
CFU/ml a
Survival
% Kill
Negative Control
1.73 to
—
—
6.10 × 10 8
Peroxide base b + 0% Barlox 12 c
1.40 × 10 8
80.9%
19.1%
Peroxide base b + 0.5% Barlox 12 c
1.70 × 10 8
98.3%
1.70%
Peroxide base b + 1% Barlox 12 c
1.72 × 10 7
9.94%
90.1%
Peroxide base b + 2% Barlox 12 c
1.26 × 10 5
0.047%
99.95%
Peroxide base b + 3% Barlox 12 c
2.86 × 10 4
0.0047%
99.995%
Peroxide base b + 4% Barlox 12 c
2.65 × 10 3
0.00043%
99.9996%
Peroxide base b + 5% Barlox 12 c
1.18 × 10 3
0.00019%
99.9998%
b contains 0 3% hydrogen peroxide, 1.0% Glycolic acid, 1.0% lactic acid, 5.0% n-propanol, 0.1% non-ionic surfactant (Iconol 24-9), 0.17% citric acid, 0.1% urea, 0.02% NaOH, 20.0% Glycerin,
c Diluted with whole milk at a ratio of 1:1.
[0027] The present invention utilizes an amine oxide, which is non-irritating to dairy animal skin and is even commonly used in cosmetic products for humans. This component is combined with one or more known germicides that are irritating at the concentrations necessary for effective germicidal activity, and/or antimicrobials that have little or no teat irritation at higher concentrations, but have not been accepted for teat antisepsis due to insufficient efficacy for a teat dip. Those types of antimicrobials include: weak acids such as alpha-hydroxy acids, lactic acid, citric acid; or glycol ethers such as phenoxyethanol or other antimicrobials that have a limited spectrum of efficacy, such as quaternary ammonium compounds or low molecular weight alcohols. Germicides that are popular for pre-milking teat antisepsis, such as hydrogen peroxide, but are irritating when used at effective concentrations on teat skin in a post milking application would benefit when combined at a low concentration with a synergist, such as an amine oxide, in accordance with the present invention. Therefore, the result of this combination is an effective teat antiseptic that is also non-irritating and non-toxic.
[0028] A preferred formulation for the present invention is as follows:
[0000]
Ingredient
Percentage
Soft Water
74.01
Caustic Soda 40%
0.02
Emollients
20.00
Citric Acid
0.170
Glycolic (hydroxyacetic) Acid (70%)
1.4300
Lactic Acid (80%)
1.1400
Iconol 24-9
0.10
Urea Prilled Uncoated
0.10
Hydrogen Peroxide 34%
0.40
Barlox 12
4.00
N-Propanol
5.00
Yellow #5 Dye
0.2000
[0029] Other advantages of the present invention are that none of the ingredients, neither the amine oxide synergist nor the germicides that are synergistic with the amine oxides, are themselves based on materials of which the global supply might be finite and eventually scarce, as is the case with iodine. Amine oxides and the majority of the synergistic germicides are plentiful, readily obtainable, not dependent on any finite raw material that is extracted from the ground, are utilized in many other industrial and consumer applications and products, and are relatively inexpensive. These ingredients are also not harmful to the environment and are readily degraded and, therefore, will not accumulate in or pollute soil or waterways into which they may be expelled after use. A further advantage to the present invention is that the antimicrobials that would be used in combination with the amine oxides are recognized in many countries where the use of teat antiseptics are regulated by governmental authorities for veterinary uses such as the European Union, South America, and Canada, as is the case for peroxides and for some alpha hydroxy acids.
[0030] As utilized herein, the terms “approximately,” “about,” “substantially,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the invention as recited in the appended claims.
[0031] It should be appreciated that the construction and arrangement of the method, as shown in the various exemplary embodiments, is illustrative only. While the method, according to this invention, has been described in conjunction with the exemplary embodiments outlined above, various alternatives, modifications, variations, improvements, and/or substantial equivalents, whether known or that are or may be presently unforeseen, may become apparent. Accordingly, the exemplary embodiments of the method, according to this invention, as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention. Therefore, the description provided above is intended to embrace all known or later-developed alternatives, modifications, variations, improvements, and/or substantial equivalents.
|
Methods and compositions for reducing the incidence of mastitis in dairy animals, the method comprising the steps of: topically applying an antimicrobial composition onto the teats or udder of the animal, the composition comprising: a first component comprising from about 2.0% to about 20.0% by weight of the composition of an amine oxide; and a second component comprising a germicide or an oxidizing agent.
| 0
|
FIELD OF THE INVENTION
[0001] This invention relates in general to the field of communication, and more specifically to a system, method, and apparatus for compressing Real-Time Transport Protocol (RTP) packet payload headers.
BACKGROUND OF THE INVENTION
[0002] Since electronic communication first began, there has always existed a desire to send more data along a given network in a shorter amount of time. Many schemes have been developed to accomplish this objective. One such scheme is to segment information into packets, compress one or more of the packets, and then send the packets to the designated receiver. The Real-time Transport Protocol (or RTP) defines a standardized packet format for delivering audio and video over the Internet.
[0003] Real-time multimedia applications over IP (e.g., VoIP) use RTP over User Datagram Protocol (UDP) as their transport protocol. A codec is a device or program capable of performing encoding and decoding on a digital data stream or signal. However, the codec must be given information about the format of the encoded data before it can decode the data. This is particularly true for variable rate codecs (e.g., AMR, EVRC). Therefore, before the data payload (e.g., voice frames, video frames) is sent over the RTP layer, an RTP media payload header specifically defined to enable the particular media codec to decode the payload is added. This payload header will appear in each RTP packet and hence contribute to the overall overhead for sending the multimedia data over IP.
[0004] There are well known techniques, such as Robust Header Compress (RoHC), developed to compress the RTP/UDP/IP headers. However, there is no method to effectively compress the aforementioned media payload header. Therefore a need exists to overcome the problems with the prior art as discussed above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The accompanying figures where like reference numerals refer to identical or functionally similar elements throughout the separate views, and which together with the detailed description below are incorporated in and form part of the specification, serve to further illustrate various embodiments and to explain various principles and advantages all in accordance with the present invention.
[0006] FIG. 1 is a diagram illustrating an exemplary communication network.
[0007] FIG. 2 is a block diagram illustrating a packet network switch.
[0008] FIG. 3 is an operational flow diagram of a header creation method.
[0009] FIG. 4 illustrates an RTP packet containing multiple media frames.
[0010] FIG. 5 is a schematic diagram illustrating communicatively coupled RTP sender and receiver according to an embodiment of the present invention.
[0011] FIG. 6 is an operational flow diagram of a header compression method at the sending device according to an embodiment of the present invention.
[0012] FIG. 7 is an operational flow diagram of a header compression method at the receiver device according to an embodiment of the present invention.
[0013] FIG. 8 is an operational flow diagram of payload header codebook updating according to an embodiment of the present invention.
DETAILED DESCRIPTION
[0014] Embodiments of the present invention provide a method and a system for compressing a payload header in a Real-Time Transport Protocol (RTP) packet. The system, according to one embodiment, includes a sending device with an RTP packet formatter for compressing an RTP packet and generating a payload header that includes information describing the compressed RTP packet. The system also includes a payload header compressor for searching for the payload header information in a first codebook, which includes a plurality of payload headers that can be indexed. In response to the payload header information being in the first codebook, the payload header is modified by replacing the payload header information with an index code in the first codebook and, in response to the payload header information not being in the first codebook, modifying the payload header by placing a codebook transmission code in the payload header.
[0015] The receiver, in accordance with one embodiment of the present invention, receives a first Real-Time Transport Protocol (RTP) packet with an index code as part of a first payload header, indexes a codebook with payload headers that can be indexed by using the index code, and then selects one of the payload headers corresponding to the index code.
[0016] In accordance with another feature of the present invention, the receiver replaces the index code in the first payload header with the selected one of the payload headers.
[0017] In accordance with yet another feature of the present invention, the receiver receives a second RTP packet with a second payload header including a codebook transmission code and further information and reads the further information in the second payload header in response to the codebook transmission code being identified therein.
[0018] In accordance with an added feature of the present invention, the receiver sends a confirmation of receipt of the codebook back to the sending device.
[0019] In accordance with yet another added feature, the receiver receives an updated codebook and then later receives a switch code to begin using the new codebook. Upon receiving a third RTP packet with a third payload header, where the third payload header has an index code, the updated codebook is indexed by using the index code in the third payload header.
[0020] An advantage of the foregoing embodiments of the present invention is that payload header compression can be easily realized.
[0021] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting; but rather, to provide an understandable description of the invention.
[0022] The terms “a” or “an”, as used herein, are defined as one or more than one. The term “plurality”, as used herein, is defined as two or more than two. The term “another”, as used herein, is defined as at least a second or more. The terms “including” and/or “having”, as used herein, are defined as comprising (i.e., open language). The term “coupled”, as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically.
[0023] Embodiments of the present invention provide to a receiver an indexed codebook containing a set of possible types and orders of media frames that will potentially be received. In one embodiment, subsequent to sending the codebook, instead of including the typical Real-Time Transport Protocol (RTP) payload header, a codebook index is included in the RTP packet. Since the size of the codebook index is usually much smaller than the RTP payload header, a compression is realized through use of the present invention. The index is easily used at the receiver side to locate the proper payload header information in a copy of the codebook stored on the receiver side.
[0024] FIGS. 1-3 illustrate an exemplary communications network ( FIG. 1 ), a packet network switch ( FIG. 2 ), and a method of header creation ( FIG. 3 ). Beginning with FIG. 1 , a representative network 100 is illustrated. The network 100 includes phones 102 and faxes 104 that are communicably coupled to a public switched telephone network (“PSTN”) 106 . Also shown in FIG. 1 is a wireless communication device 120 that communicates with and through a wireless communication system infrastructure 122 to link to the PSTN 106 .
[0025] The PSTN 106 is communicably coupled to a switch 108 and an Internet Protocol (“IP”) network 110 . One function of the switch is to convert time division multiplexing (“TDM”) based communications 112 to IP-based communications or “packets” 114 . The switch 108 creates IP packets 114 containing destination information necessary for the packets 114 to be properly routed to their destinations, which may include computers 116 or other devices communicably coupled to the IP network 110 .
[0026] A network controller 118 is communicably coupled to the PSTN 106 and the switch 108 , and provides control signals to the switch 108 for proper processing of the TDM-based communications 112 . The Network controller 118 can function as a Media Gateway Control (“MGC”), which converts audio signals carried on telephone circuits, such as the PSTN 106 to data packets carried over the Internet or other packet networks, such as IP network 110 . As will be appreciated by those skilled in the art, the present invention is not limited to the conversion of TDM based communications to IP-based communications; instead, the present invention may be applied to any conversion of a multiplexed communication to a packet-based communication.
[0027] The internet protocol (IP) specifies the format of packets and the addressing scheme used. Many networks combine IP with a higher-level protocol such as the Transport Control Protocol (“TCP”), which establishes a virtual connection between a destination and a source. IP network 110 receives and sends messages through switch 108 , ultimately to wireless communication device 120 , phone 102 , or fax 104 . Computers 116 receive and send messages through IP network 110 in a packet-compatible format.
[0028] In FIG. 2 , a block diagram of a packet network switch 200 is shown and in FIG. 3 , a header creation method is shown. As can be seen in FIG. 2 , the packet network switch 200 includes a digital signal processor (“DSP”) 202 communicably coupled to a CPU 204 and router 206 communicatively coupled to the CPU 204 .
[0029] When converting the TDM-based communications 112 to the IP-based communications 114 , the CPU 204 receives signaling instructions for the call, as shown in step 302 of FIG. 3 , and assigns the DSP 202 to process the call in step 304 . The DSP 202 responds by receiving the call data in step 306 . The DSP 202 then compresses the data and creates a data portion of the packet in step 308 . In step 310 , the DSP 202 sends the data portion of the packet to the CPU 204 . The CPU 204 creates a RTP header (and RTP payload header), attaches the RTP header (and RTP payload header) to the data portion of the packet and sends the packet to the router 206 in step 312 . In step 314 , the router 206 creates a user datagram protocol (“UDP”) header, internet protocol (“IP”) header and media access control (“MAC”) header and attaches these headers to the packet. The router 206 then sends the complete packet (data plus headers) out over the IP network in step 316 . If the call is terminated, as determined in decision step 318 , the process ends at step 320 . If, however, the call is not terminated, the DSP 202 receives more call data in step 306 and the above-described process repeats until the call is terminated. As illustrated, both the CPU 204 and the router 206 share the responsibility for header creation in the packet network switch 200 .
[0030] FIG. 4 illustrates a typical packet 400 containing multiple media frames 410 a - 410 n which are the storage bins that hold the actual media information that is to be communicated. The packet 400 also includes 4 headers—an IP header 402 , a UDP header 404 , an RTP header 406 , and an RTP payload header 408 . The first three headers, 402 , 404 , and 406 use known header compression methods (e.g., RoHC) to reduce their size.
[0031] The payload header 408 depicts the type and order of media frames contained in the RTP packet (e.g., 1 full rate and 2 half rate frames in half/full/half order). Therefore, the payload headers between two RTP packets will always be identical if they contain the same number of media frames of the same types in the same order.
[0032] For a given RTP session, only a limited number of combinations of different types, order, and numbers of media frames will be used by the RTP sender in its outgoing RTP packets. Moreover, in many practical situations the majority of the RTP packets from the same sender will most likely use only a very small number of the possible combinations.
[0033] RTP payload headers, such as RTP payload header 408 , are generally defined by the Internet Engineering Task Force (IETF) which develops and promotes Internet standards. The headers are used for bundling multiple media frames generated by most modern variable rate codecs like AMR, SMV, or EVRC before sending them over IP. The present invention, as will be discussed in detail below, compresses the RTP payload header more efficiently than any of the heretofore known methods. The inventive RTP payload header compression differs from the standard compression methods used for the RTP/UDP/IP headers 402 - 406 shown in FIG. 4 .
[0034] FIG. 5 is a schematic diagram of a communicatively coupled RTP sender 502 and an RTP receiver 504 . FIGS. 6 and 7 are operational flow diagrams of the sender 502 and receiver 504 according to one embodiment of the present invention. More specifically, FIG. 6 shows the process that occurs on the sender side, FIG. 7 shows the process that occurs on the receiver side, and FIG. 5 shows the interrelation between the two. The steps occurring on the RTP sender 502 will first be described with reference to FIGS. 5 and 6 .
[0035] Before the start of an RTP session, the RTP sender 502 identifies the subset of possible combinations that will be most frequently used for the session (this can often be derived by analyzing the Session Description Protocol (SDP) parameters of the session, from an algorithm, or from history), and in step 602 , constructs a codebook 514 that contains a list of payload header variations corresponding to the subset and stores it in a memory 511 . In step 603 , the codebook 514 is sent, via an output 515 , to the receiver 504 , via an input 517 , where it is stored as a receiver codebook 520 . In embodiments of the present invention, passing of the codebook from the sender to the receiver is part of the call flow or can be an off-line event (e.g., sender created the codebook a priori and uses manual means to deliver and install the codebook at the receiver before the session). In other embodiments, the codebook can be part of the engineering design, created when the sender and receiver are built.
[0036] The RTP sender 502 includes a media encoder 506 . A media encoder is a production tool that enables content developers to convert audio, video, and computer screen images to a media format suitable for delivery to users. The media encoder 506 receives the data to be transmitted to the receiver and encodes the data for transmission in step 604 .
[0037] An RTP packet is formed in step 606 by the RTP packet formatter 508 , which compresses the media data and creates a data portion of the packet. In a step 607 , before sending out an RTP packet, the payload header compressor 516 will search for the payload header information in the first codebook that includes payload headers that can be selected by an index code.
[0038] If the payload header information is found (step 608 ), a processor 501 communicatively coupled to the memory 511 and the payload header compressor 516 will modify the payload header by replacing the payload header information with an index code in the codebook 514 corresponding to the appropriate payload header (step 610 ). Alternatively, in step 612 , the processor 511 will cause the payload header compressor 516 to leave the payload header information in the packet and will insert a special codebook transmission code or “escape code” before it. The escape code is a signal to the receiving device 504 that there is no entry in the codebook containing the particular payload header and to not waste time searching for it. In step 614 , the sender 502 will send (via output 515 ) the altered packet to the receiver 504 .
[0039] A record, or log, is kept which identifies the type and order of media frames contained in each RTP packet (e.g., 1 full rate and 2 half rate frames in half/full/half order). Although the payload header will vary from packet to packet when the compression amounts and data types vary between them, payload headers between two RTP packets will always be identical if they contain the same number of media frames of the same types in the same order. In practice, only a limited number of combinations (of different types, order, and numbers of media frames) will be used by the RTP sender in its outgoing packets for a given RTP session. Moreover, in many practical situations the majority of the RTP packets from the same sender will most likely use only a very small number of the possible combinations.
[0040] To keep track of these combinations, in step 616 , a payload header statistics collector 510 stores payload header statistics, i.e., tracks each packet formed by the RTP packet formatter 508 . In step 618 , the statistics are compiled by a codebook generator 512 into a record that lists each or most of the possible combinations of payload header information that is needed in a particular session to properly describe the packets.
[0041] After a sufficient number of statistics have been collected, the codebook generator 512 generates an updated codebook 530 (step 620 ), which is made available to the payload header compressor 516 .
[0042] FIG. 7 shows the process flow steps performed at the receiver 504 . In step 700 , the codebook 520 is received (via input 517 ). In step 702 , a confirmation from the session control signaling logic 533 is sent (via output 519 ) back to the sender 502 , which receives it via input 521 and corresponding session control signaling logic 503 . In step 704 , an RTP packet 528 with an index code as part of the compressed header is received. Upon receipt of the compressed RTP packet, a payload header decompressor 518 checks (step 706 ) whether the beginning bits of the payload portion of the packet are a code book transmission code, also referred to as an “escape code”. If they are, in step 708 , the receiver recovers the original RTP packet by simply removing the “escape code” from the beginning of the payload, reads further information in the payload header for interpreting the RTP packet, and continues the process with step 714 . If the escape code is not present in the payload header, the payload header decompressor 518 grabs the beginning bits of the payload, which will be used as a codebook index, and in step 710 a processor 527 communicatively coupled to a memory 529 storing the codebook 520 uses the index code to select one of the payload headers in the codebook corresponding to the index code.
[0043] In step 712 , the payload header decompressor 518 recovers the original RTP packet by replacing the index code in the compressed payload header with the retrieved payload header from the stored codebook 520 .
[0044] Now that the payload header contains all of the necessary information for decompression, an RTP packet decompressor 524 unpacks the RTP packet in step 714 . In step 716 , a media decoder 526 converts the data back to a format suitable for media players.
[0045] With a small but well constructed codebook to cover the most frequently occurring payload headers in a session, the size of the indices can be far smaller than that of the actual payload headers and significant compression is achieved. The payload header compression scheme, in accordance with embodiments of the present invention, has the advantage of being: a) lossless, b) robust to RTP packet drops, c) very simple in terms of computation and implementation, d) stateless, and, e) highly effective.
[0046] Table 1 shows a first exemplary payload header in an Adaptive Multi-Rate (AMR) over RTP session compressed by the present invention. AMR is an audio data compression scheme optimized for speech coding. The RTP session description parameters are defined as follows:
[0047] m=audio 49120 RTP/AVP 97
[0048] a=rtpmap:97 AMR/8000/1
[0049] a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2; mode-change-neighbor=1
[0050] a=maxptime:20
[0051] The description defines a single channel session with four rates (4.75 k, 5.90 k, 7.95 k, 12.2 k) allowed. Moreover, the Bandwidth-Efficient Mode is used and maxptime=20 means that only one media frame is allowed in each RTP packet (as described in IETF RFC 3267).
[0052] With these restrictions, the normal (i.e., uncompressed) payload header for the session is 10 bits long, as shown below:
[0000]
[0053] The first four bits are the codec mode request (CMR), which is for the sender of the RTP packet to request the receiver of the RTP packet to use the codec mode indicated when the receiver of the RTP sends RTP packets in the reverse direction. If no codec mode change is requested, the value of CMR is equal to 15 indicating that no mode request is present. The next bit defines what follows the frame. More specifically, if the bit is set to 1, it indicates that the frame is followed by another speech frame and if the bit is set to 0, it indicates that the frame is the last frame in the payload. The next 4 bits are the frame type (FT). For the exemplary session the FT field will take only one of 6 values (0, 2, 5, 7, 8, and 15) and FT=8 (SID) or 15 (blank) will occur only in a very small percent of packets. A quality is defined in the 9 th bit Q, followed by a speech data frame. For the vast majority of the packets, CMR will be 15 (no mode change request), F will be 0 (since only one media frame is allowed per packet in the session), and Q will be 1 (undamaged speech).
[0054] With the above knowledge of the session, the following exemplary codebook could be created by the RTP sender for the session:
[0000]
TABLE 1
CODEBOOK INDEX
PAYLOAD HEADER
NOTE
0 0
one good 12.2 kframe, no CMR
0 1
one good 7.95 kframe, no CMR
1 0
one good 5.90 kframe, no CMR
1 1 0
one good 4.75 kframe, no CMR
1 1 1
(original payload header)
The Escape Code
[0055] Given the following facts for this AMR session:
[0056] Always one frame per RTP packet due to maxptime=20;
[0057] SID frames will be few and rare since DTX (discontinuous transmission control) will remove most silence periods;
[0058] Bad quality and blank frames will be few and rare under normal conditions; and
[0059] Rate change request frames will be few and rare under normal conditions and the majority of frames will be of higher rates (12.2 k or 7.95 k) under normal conditions (session will only attempt to change to lower rates in response to a resource crunch),
[0060] We can give a very conservative assumption of a distribution of 40%, 40%, 10%, 5%, 5% for index 00, 01, 10, 110, and 111, respectively. The above illustrative codebook, with the aforementioned compression scheme, can then compress the original 10 bit payload header down to an average of 2.6 bits per packet for the session, i.e., a compression ratio of 74% is achieved. The codebook should use no more than 25 bytes to send and that can be easily passed in the session setup signaling.
EXAMPLE 2
[0061] In a second example, the payload header in an AMR over RTP session is compressed using the present invention. The RTP session description for this second example is as follows:
[0062] m=audio 49120 RTP/AVP 99
[0063] a=rtpmap:99 AMR-WB/16000/2
[0064] a=fmtp:99 interleaving=30; mode-set=0,1,2,3,4,5,6,7
[0065] a=maxptime:20
[0066] The session description calls for a two channel session with AMR-WB rates 0-7 allowed. Moreover, octet-align payload header format will be used and maxptime=100 means that one to five media frame blocks are allowed in each RTP packet. Furthermore, interleaving=30 means that the session will use frame-block interleaving and the sender will set an interleaving group size value<30 frame-blocks. With these restrictions, the normal (i.e., uncompressed) payload header for the session will look like the following:
[0067] For packets containing 5 frame-blocks (96 bits):
[0000]
[0068] For packets containing 4 frame-blocks (80 bits):
[0000]
[0069] For packets containing 3 frame-blocks (64 bits):
[0000]
[0070] For packets containing 2 frame-blocks (48 bits):
[0000]
[0071] For packets containing 1 frame-blocks (32 bits):
[0000]
[0072] Under normal conditions, the session would have the following characteristics:
[0073] Rate change request will be few and rare, therefore CMR field will mostly be 15;
[0074] Damaged frames will be few and rare, therefore Q bits will mostly be 1's;
[0075] ILL (interleaving) will be a fixed value (below 30, in fact it must be no larger than 15) selected by the sender and won't change for the entire session;
[0076] FT fields can have a value from 0-7, 9, 14, 15;
[0077] FT fields for the same frame-block (e.g., 1 L/1 R) will always have the same value;
[0078] FT values 9 (SID), 14 (speech lost), and 15 (no data) are rare and few; Since rate changes are infrequent under normal conditions, the majority of the packets will contain frame-blocks of the same FT values.
[0079] The sender will most likely always put a fixed number (<=5) of frame-blocks in a packet as long as it can. Only the packets at the boundaries of a speech burst may contains a different number of frame-blocks.
[0080] With the above knowledge about the session (and working with the assumption that the sender has decided to use ILL=4 and 4 frame-blocks per packet), the sender can construct the following exemplary codebook.
[0000]
TABLE 2
Exemplary Codebook for Example 2.
INDEX
PAYLOAD HEADER
NOTE
0xxyyywhere,xx:00-11yyy:000-111(represents32indices)
4 goodframe-blocks ofthe samerate yyy(0-7);ILP=xx(0-3); CMR=15
100xxyyywhere,xx:00-11yyy:000-111(represents32indices)
3 goodframe-blocks ofthe samerate yyy(0-7);ILP=xx(0-3); CMR=15
101xxyyywhere,xx:00-11yyy:000-111(represents32indices)
2 goodframe-blocks ofthe samerate yyy(0-7);ILP=xx(0-3); CMR=15
110xxyyywhere,xx:00-11yyy:000-111(represents32indices)
1 goodframe-blocks ofthe samerate yyy(0-7);ILP=xx(0-3); CMR=15
111
(original payload header)
The Escape
Code
[0081] Assuming a distribution of 75%, 5%, 5%, 5%, and 10% for index groups 0xxyyy, 100xxyyy, 101xxyyy, 110xxyyy, and 111, respectively, for the session (very consecutively based on the aforementioned session characteristics), the uncompressed payload header size can be estimated at around an average of 74.56 bits per packet. With the aforementioned compression scheme and the simple exemplary codebook in table 2, it can be estimated that the compressed payload header size would be averaged around 13.36 bits per packet, representing an 82% compression ratio. The exemplary codebook in table 2, with a size of about 1.1 kB if encoded in binary form, can be easily passed to the receiver during the session setup signaling.
[0082] It is not difficult to see that with a more carefully designed codebook with more entries, higher compression ratios are very reachable. It is worthwhile to note that the AMR RTP payload header format used in the above example is among the most complicated payload header formats used in the modern codecs. With a simpler payload header format from a different codec, the efficiency and simplicity of this invention could be even more evident.
[0083] Furthermore, for the template-based RTP payload header compression scheme just described, the use of a codebook that closely matches the distribution of the actual payload headers used in a given session will improve the compression ratio of the scheme. However, though the initial codebook can be based on some heuristic approach using configuration information such as session parameters or history, it is desirable to find a systematic way to automatically establish a good codebook for a given session. Therefore, embodiments of the present invention provide a method for generating a second codebook that is more narrowly tailored for a particular call session and for transmitting the second improved codebook to the receiving device. An embodiment supporting this improved codebook generation method is shown in FIG. 8 .
[0084] When starting a new RTP session, the RTP sender that employs the template-based payload header compression method according to the previously-described embodiments of the present invention can first use an initial payload header codebook, which is constructed with either past payload header statistics or with some heuristic approach based on the session parameters. The RTP sender 502 sends the initial codebook 514 to the receiver in step 802 . The receiver stores the initial codebook 520 and sends a response to the sender in order to confirm receipt as shown in steps 702 and 704 in FIG. 7 . In step 804 , bearer traffic with payload compressed headers starts flowing from the sender 502 to the receiver 504 .
[0085] During the session, the RTP sender uses the payload header statistics collector 510 , shown in FIG. 5 , to keep a count for each different uncompressed payload header it has sent (two uncompressed payload headers are considered different if they are not of the exact length or of the same bit pattern). At some pre-set point in time (e.g., 15 sec into the session) or when the total count of all payload headers sent reaches a pre-set value (e.g., 1000), the RTP sender 502 in step 806 builds an improved codebook based on the collected payload header statistics (e.g., using some standard prefix-free code generation algorithms such as Huffman coding). In the same step, 806 , the RTP sender 502 passes the new updated codebook 530 to the RTP receiver 504 via a “payload-header-codebook-update” message (e.g., an out-of-band SIP-like message). Upon receipt of the new codebook 530 , the RTP receiver 504 stores (step 808 ) the new codebook, while continuing to use the old codebook 520 to decode the incoming RTP packets and responds with a “payload-header-codebook-confirm” message (e.g., an out-of-band SIP-like message).
[0086] It should be noted, however, that in certain embodiments of the present invention, where codebook updating is implemented and employed in an RTP session, every time the sender generates a new codebook, and before it triggers a codebook update, the sender may first check how different this new codebook is from the one being used. If the difference is determined to be insubstantial, it may choose to skip the update and continue to collect session statistics.
[0087] Upon receipt of the “payload-header-codebook-confirm” message, in step 810 , the RTP sender starts compressing all subsequent outgoing RTP packets with the new codebook and inserts a special “switch-codebook” code before the compressed payload header of each outgoing packet to create a second generation RTP packet 532 . Upon receipt of the first incoming compressed packet 532 with the special “switch-codebook” code, the RTP receiver, in step 812 , makes a switch from the old codebook to the new codebook that it has already received in step 808 . In step 814 , the RTP receiver responds with a “payload-header-codebook-changed” message (e.g., an out-of-band SIP-like message).
[0088] It should be noted that in embodiments of the present invention, the new codebook sent from the sender 502 , the confirmation of receipt of the new codebook, and the confirmation of switch to new codebook are not intended to be embedded in the RTP but rather are communicated in out-of-band signaling. One implementation is to add them to mid-session call signaling.
[0089] After performing the codebook switch, as executed in steps 806 - 814 , If more packets arrives at the RTP receiver with the special “switch-codebook” code, the RTP receiver, in step 816 , ignores the special “switch-codebook” code. When the RTP sender receives the “payload-header-codebook-changed” message from the RTP receiver, the sender stops inserting the special “switch-codebook” code into subsequent outgoing packets in step 818 . The codebook update process is completed at this point.
NON-LIMITING EXAMPLES
[0090] Although specific embodiments of the invention have been disclosed, those having ordinary skill in the art will understand that changes can be made to the specific embodiments without departing from the spirit and scope of the invention. The scope of the invention is not to be restricted, therefore, to the specific embodiments, and it is intended that the appended claims cover any and all such applications, modifications, and embodiments within the scope of the present invention.
|
An RTP payload header ( 408 ) is compressed by utilizing a codebook ( 514 ) that holds one or more indexable payload header variations and sending it to a receiving device ( 504 ). An RTP packet ( 400 ) that includes the payload header ( 408 ) with information pertaining to the packet is generated by a sending device ( 502 ) and the codebook is searched for the payload header information. If the information is found, the payload header ( 408 ) is replaced with a short index in the codebook ( 514 ). At the receiving device ( 504 ) the index is used to retrieve a payload header variation that corresponds to the index and the variation is placed back into the payload header ( 408 ) to uncompress the header.
| 7
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to dynamoelectric machines such as large induction motors, and more particularly this invention relates to an induction motor for driving large inertia loads having a hollow ferromagnetic rotor and means for transferring heat therefrom.
2. Description of the Prior Art
Various methods are available for starting reversible pumped storage generator-motors. One method currently used is by means of a starting motor which is mounted directly on the main machine shaft. In such an arrangement a large wound rotor motor is often used. This motor is rather expensive and requires a rheostat (usually a water rheostat) to dissipate the energy involved during starting. This energy is, as a minimum, equal to H.KVA of the large machine being started where H is the inertia constant in KW seconds per KVA stored energy of rotation. This is further increased by the speed difference of the wound rotor induction motor synchronous speed compared to the rated speed of the large synchronous motor. It is also increased by the torque required to overcome friction and windage losses in both the generator motor and pump compared to the torque which is directly applied to the inertia for acceleration.
The rotor assemblies for starting motors suitable for use with hydrogenerators are relatively large in physical size and, although they rotate at relatively low speeds., their large diameter and great weight result in moderately high centrifugal forces at the periphery of the rotor during operation. The rotational forces in combination with the differential heating caused by the circulation of heavy induced currents during starting make the ordinary squirrel cage rotor assembly unsuitable for this application since the rotor bars tend to heat and expand unevenly and cannot withstand the large mechanical and thermal stresses.
The mechanical and thermal problems involved in this type construction have been increasingly severe, and alternative starting arrangements such as asynchronous starting at full or reduced line voltage have been utilized. However, the disturbing effects of large current inrush on the interconnected network and heating of the damping windings are sometimes encountered when the asynchronous starting method at full or reduced line voltage is used, so that satisfactory designs of the this type are not always possible.
SUMMARY OF THE INVENTION
In accordance with the present invention, an induction motor is provided which is suitable for driving a large inertia load and is especially suited for starting a reversible, pumped storage hydrogenerator-motor with the starting induction motor mounted on the main machine shaft.
The invention provides an induction motor having a generally conventional stator assembly and a rotor which comprises a continuous circular metallic rim for dynamic interaction with the magnetic field established by the stator assembly and a closed container of cooling fluid having a large thermal capacity for transferring heat from the rim during starting periods. The rim is generally cylindrical and is formed of high strength steel of suitable thickness and length. The rotor assembly operates with an air gap which is generally larger than normal as compared to the air gap of an equivalent wound rotor motor to allow for radial expansion of the rim in response to temperature changes. Because the amount of heat to be stored in the rotor for starting large generator-motor units is more than can be safely stored on such a thin steel rim, particularly when several starts are required in a short time (generally under 2 to 4 hours), a container of cooling fluid is provided on the inside face of the rotor rim so that the cooling fluid will be in direct contact with the rim and will absorb the heat generated whenever the rim is warmer than the cooling fluid. As the rotor speed increases the cooling fluid inertia provides a relative velocity in addition to connection between the cooling fluid and the rotor rim, thus aiding heat transfer.
In the preferred embodiment of the invention, water is used as a cooling fluid in order to absorb a large amount of heat. With a radial water container dimension 3 to 4 times the rim thickness most starts will not heat the water to boiling temperature. If the rim reaches temperatures above 100° C, the water will absorb large amounts of heat as it turns to steam, thus controlling the temperature of the surface of the rim next to the water. The steam is transported toward the center of the rotor due to centrifugal force on the water. The steam either heats the remaining water or escapes through a vent to a desired location via a hose or pipe to an area preferably outside the machine where it cannot cause harm. By this method the volume of water compared to the volume of the rim can be kept within practical dimensions and a great deal of heat can be absorbed without an expensive water rheostat as described above.
Since this type of application normally has a load torque curve which is nearly proportional to speed squared due to windage and pump losses, it is desirable to limit the rate of heat input to the rotor during low speed operation. A small depth of flux penetration into the rotor is necessary to accomplish this at low speed. This is obtained in the present invention by controlling the impedance of the stator winding of the induction motor during the starting mode whereby polyphase currents flowing in the stator winding are reduced during low speed operation and are increased as the starting motor rotor approaches a predetermined synchronizing speed. Heat buildup in the rotor rim is greatly minimized and the stresses due to thermal cycling are maintained sufficiently below the yield point of the rim material thereby providing satisfactory starting during a reasonably short time period. In addition, means are provided for changing the cooling fluid on a slow replacement or recirculation basis and for cooling it by means of a small external heat exchanger at a rate which is not necessarily sufficient to accommodate the total losses during the starting period, but which is sufficient to remove most of the stored heat before another start. Thus the starting motor of the present invention can provide multiple starts in a single day for many years without risk of heat damage.
The foregoing and other objects, advantages, and features of this invention will hereinafter appear, and for purposes of illustration, but not of limitation, an exemplary embodiment of the subject invention as shown in the appended drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified vertical sectional view, with some parts in elevation, of a vertical-shaft water wheel generator assembly and a starting motor which incorporates the present invention mounted on the shaft in operating position;
FIG. 2 is a plan view of the rotor assembly of the starting motor illustrated in FIG. 1;
FIG. 3 is a sectional view substantially on the line III--III of FIG. 2;
FIG. 4 is an electrical schematic diagram of the stator assembly of the starting motor illustrated in FIG. 1 in which a reactor is connected;
FIG. 5 is a schematic diagram of an external cooling arrangement for the rotor of the induction starting motor of FIG. 1;
FIG. 6 illustrates an alternative embodiment of a resilient supporting arrangement for the rotor assembly of the starting motor of FIG. 1;
FIG. 7 is a block diagram which illustrates an alternative winding energizing arrangement for the starting motor of FIG. 1;
FIG. 8 is a circuit diagram of an alternative embodiment of the stator winding of the starting motor of FIG. 1; shown in unmodulated condition; and
FIG. 9 is a circuit diagram of the winding of FIG. 8 shown in reconnected, modulated condition.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention as shown in the drawing is embodied in an induction motor which is mounted in operating position upon the shaft of a large reversible pumped storage hydrogenerator-motor unit. A starting motor which incorporates the invention is especially well suited for starting large inertia loads and therefore may find utility in related applications.
Referring first to FIG. 1, there is shown a large induction starting motor 10 which has a rotor assembly 12 constructed according to the teachings of the present invention and which is mounted in operating position upon a shaft 14 for concurrent rotation with the rotor of a large vertical shaft water wheel or hydraulic turbine assembly 16 which includes a foundation 18 and a pit 20. A vertical shaft water wheel or hydraulic turbine 22 is mounted within the pit 20, the water wheel having parts, such as a rotor 24, shaft 26, and head cover 28, which are vertically removable via being lifted out of the pit 20. The foundation 18 has a bearing supporting ledge portion 30, and a brake and jack supporting ledge portion 32, both of the ledge portions being above the pit.
The bearing supporting ledge 30 supports a thrust bearing supporting bracket 34, which carries a thrust and guide bearing assembly 36 which supports a vertical generator shaft 38 in any suitable manner. The generator shaft 38 has an upper shaft portion 40 and a lower shaft portion 42, respectively extending above and below the thrust bearing 36. The downwardly extending shaft portion 42 terminates in a coupler 44 for coupling the same to the water wheel shaft 26.
The upper shaft portion 14 of the generator assembly 16 carries a generator rotor 46 which is spaced above and separate from a flywheel 48 and its spider supporting assembly 50. The generator rotor 46 is surrounded by a generator stator 52, the periphery of which is provided with a suitable supporting means such as the structural supporting assembly 54 which is supported on an upper part of the foundation 18, so that the stator and rotor may operate independently with respect to each other.
The upper shaft portion 14 of the generator also carries the starting motor rotor assembly 12 of the starting motor 10 for concurrent rotation with the rotor 46 of the generator assembly 16. The starting motor rotor 12 is surrounded by a starting motor stator 56, the periphery of which is provided with suitable support by means of a vertical extension 55 of the structural supporting assembly 54.
The purpose of the starting motor 10 is to bring the rotor 46 of the generator assembly 16 up to synchronous speed during starting in either the pumping mode or the generating mode. Therefore the starting motor rotor 12 is mounted directly to the shaft 14 for concurrent rotation with the rotor 46 of the generator assembly. During starting, large starting currents are circulated in the starting motor rotor 12 which generates a large amount of thermal energy which is generally proportional to the inertia of the rotor assembly and its resistance torque. This heat must be dissipated within the mass of the rotor assembly or must be evacuated to limit the temperature gradient and the accompanying mechanical stresses to values compatible with good behavior of the machine. As the thermal energy dissipated per unit of rotor surface area increases, rotor assemblies which utilize conventional construction including rotor bars or solid pole members become subject to physical expansion due to temperature differentials within the rotor structure, therefore making such arrangements unsuitable. Therefore, improved rotor construction is desirable for applications involving high energy starting levels or shorter starting periods.
According to the present invention, as illustrated in FIGS. 1, 2, and 3, the rotor assembly 12 is provided with a continuous circular metallic rim 60 to which a closed container 62 of a suitable cooling fluid 64, such as water, is connected so that the cooling fluid is in thermal communication with the inside diameter of the rim 60 to transfer thermal energy therefrom. A cooling fluid other than water may be used to good advantage. It is preferred that the cooling fluid 64 be in intimate contact with the inside diameter of the surface of the rim 60 for maximum heat transfer purposes. Because of the unusually high level of heat generated during the starting mode, the rotor assembly 12 should have a very large thermal capacity; thus, the volume of the cooling fluid 64 should be large as compared with the volume of the metal comprising the rim 60.
The stator member 56 of the starting motor 10 may be similar to that of a conventional wound rotor motor or of a squirrel cage motor. The rotor 60, however, is a continuous cylindrical rim of suitable strength steel of suitable thickness and length operating with an air gap 66 which is generally larger than normal for a corresponding conventional wound rotor or squirrel cage motor. The large energy storage (in the form of heat) in the rotor 12 of the starting motor 10 is more than the relatively thin rim 60 can store, particularly when several starts are required in a relatively short time (under 2 to 4 hours). Therefore, the water chamber 62, or "water tank" is formed on the inside diameter surface of the rotor rim 60 so that the water 64 is in direct contact with the rim and absorbs the energy transmitted thereto whenever the rim 60 is warmer than the water. As the speed of rotation increases, the inertia of the water 64 will cause a relative velocity between it and the rotor rim, thus aiding heat transfer. As the rim 60 reaches temperatures above 100° C the water will absorb large amounts of heat as it turns to steam, thus controlling the temperature of the surface of the rim next to the water. As the water vaporizes, steam 67 moves toward the center of the rotor 12 due to centrifugal force on the water and to the top of the water chamber 62 and either heats the remaining water or escapes through a vent 70 to a desired location by conduit means 73 such as a hose or pipe to an area preferably outside the machine where it will not cause harm.
It is known that conventional rotors cannot operate for extended periods under heavy load conditions because the practical heat dissipation rates in such structures will cause high temperature differences with resultant stresses in the rotor above its yield point. Whenever this is true the rotor is only good for a limited number of cycles or starts before thermal checking or cracks start to occur in the heated surface which progress to the point of destruction. However, with a thin rim of suitable thickness and of moderate yield point steel, and with the temperature held reasonably uniform by cooling fluid and a suitable length of rim to stator, the stresses can be maintained sufficiently below the yield point of the rim material to be good for starting several times a day on the average for 20 to 30 years.
Referring now to FIGS. 2 and 3, the rotor 12 has a metallic web supporting member 71 secured between the shaft 14 and the cooling fluid container 62 to support the rim 60 and water tank 62 for rotation within the stator member 56. The web supporting member 71 as illustrated has the general outline of a spider member with a plurality of radial arms 72 which are reinforced by suitable structural members 74. The spider member 71 has a fabricated hub portion 76 which is suitably secured to the shaft 14 for rotation therewith. The cylindrical water tank 62 is supported on the outer ends of the radial arms 72, and the solid rotor rim 60 is secured to the water tank 62 by any suitable means such as welding.
As previously discussed, the high temperatures as well as the large diameter and great mass of the rotor of this type results in high rotational forces on the rim 60 when it is rotating and conducting current during the starting mode. To accommodate radial expansion of the rotor assembly 12, the cylindrical rotor assembly 12 is connected to the shaft 14 by means of the arm members 72 which are joined to the inside diameter of the water tank 62 by means of resilient spring key connecting assemblies 77. The amount of spring deflection within the spring connecting means 77 and the load on the rim 60 and the spider 71 can all be varied as necessary, thus providing considerable flexibility in design.
An alternate resilient supporting arrangement is illustrated in FIG. 6 of the drawing. In this assembly, the inside rim of the water tank 62 is fitted around a pair of axially spaced, radially extending circular plate members 79 and is joined thereto by a pair of annular spring members 81, 85. The plate members 79 are suitably joined to the shaft 14 and are braced to limit axial deflection. The annular spring members 81, as illustrated, preferably has a cross-section in the form of an inverted "U", with lip portions 83 welded or otherwise suitably joined to the radial plate 79 and tank 62. The inside rim of the water tank 62 is preferably secured to the plate members 79 by heat shrinking to moderate the stress imposed by thermal expansion. This assembly provides a flexible diaphram which is tangentially stiff for the transmission of torque, but which is radially resilient to allow uniform radial expansion of the rim 60 as its temperature increases.
The performance of the induction motor 10 having a hollow, continuous ferromagnetic rim rotor structure 60 may be characterized by the electromagnetic torque resulting from eddy currents of such a rotor reacting with an inducing field from the stator 56. These eddy currents are known to have a distribution and a definite depth of penetration beyond which the field quantities are negligibly small. It has been found that hollow ferromagnetic rotors with a radial wall thickness corresponding to substantially the depth of penetration of the eddy currents compares favorably in performance with a solid rotor of identical material and the same air gap. Thus for improved performance the radial thickness of the rim 60 may be constructed substantially equal to the maximum depth to which eddy currents induced therein by the stator 56 are capable of penetrating. However, the proper rim thickness is also determined by the requirements of thermal capacity and flux capacity. If the rim is too thick, thermal differential effects may cause it to rupture. But it must be thick enough to provide sufficient flux capacity to achieve adequate pull-in torque. It has been determined that a rim thickness (for high strength steel) of 11/2 to 3 inches satisfies these requirements for typical pumped storage applications.
For large inertia loads, the output of an induction motor can be characterized by a load torque curve which is nearly proportional to speed squared due to windage and pump losses. Therefore it is desirable to limit the rate of heat input to the rotor 12 at low speeds and small depth of flux penetration. This may be achieved in the present invention by introducing impedance control means into the stator winding 56 of the starting motor 10 as illustrated in FIG. 4 of the drawing. The winding 56 comprises phases A, B, and C which receive power from a three phase source through a suitable contactor 87 and transmission lines 101, 103, and 105. The preferred impedance control means comprises a polyphase saturable reactor 80 which is connected in series electrical relationship with the neutral of the polyphase stator winding 56. The saturable reactor 80 includes a plurality of impedance elements 82, 84 and 86 which may be trimming reactors or resistors which are switched in and out of the circuit by means of contactor switching elements 88 which may be selectively energized and coordinated for progressively bypassing the impedance elements as the starting motor rotor speed increases. Therefore, from rest to a suitable speed of 40% to 80% of synchronous speed, the maximum reactor impedance may be inserted into the neutral of the stator winding 56. Then with low slip near synchronous speed, where the flux can penetrate deeper in the rim without excessive loss rates, the reactor 80 may be shorted out in one or several steps to produce much higher torques to overcome the losses in the generator motor unit to reach a suitable synchronizing speed. The synchronous speed of such an induction starting motor is usually close enough to the main unit rated speed, and the acceleration rates are low enough, that manual or automatic synchronizing can be readily employed.
While FIG. 4 shows the reactor 80 connected in the neutral of the stator winding 56, the reactor could also be placed in the line side with slightly different switching so that one reactor could serve a number of starting motors in a multiple unit station.
As a further means of limiting the heating rate of the rotor 12 during starting, the stator winding 56 of the starting motor 10 is provided with suitable coil connecting points and suitable switching means 89 so that it can be connected to provide alternative pole numbers and thereby reduce its synchronous speed and also increase starting torque. This arrangement may be realized by a standard two-speed winding combination, or by a more sophisticated winding connection arrangement known as pole-amplitude modulation as shown in FIGS. 7, 8, and 9. A number of patent specifications and technical articles explain this method, including G. H. Rawcliffe, "Induction Motor Speed Changing by Pole Amplitude Modulation," Proceedings of the Institution of Electrical Engineers, Vol. 105, Part A, No. 22, Aug. 1958; and, G. H. Rawcliffe, "Speed Changing Induction Motors -- Further Developments in Pole-Amplitude Modulation," Proceedings of the Institution of Electrical Engineers, Vol. 107, Part A, No. 36, Dec. 1960. The control of speed by pole manipulation may be practiced either independently or in conjunction with reactor impedance control to limit the heating rate of the rotor rim 60 during starting.
A further improvement in the cooling of the rotor assembly 12 is illustrated in FIG. 5 in which the cooling fluid is replaced by cooling fluid pumped from an external reservoir or heat exchanger 90. The cooling fluid 64 is introduced into the tank 62 through a conduit 69 and is transferred therefrom through the conduit 73 to the heat exchanger 90 by means of a pump assembly 92. The cooling fluid is preferably introduced and discharged through a pair of concentric coolant tubes 94, 96 extending through the central bore of the shaft 14 in the conventional manner. Circulation of the cooling fluid 64 throughout the tank 62 is illustrated by the arrows 98. The cooling fluid is preferably cooled or exchanged externally on a slow replacement or recirculation basis which may not necessarily be sufficient to take care of the total loss incurred during the starting period, but preferably is sufficient to remove the total accumulation of heat before another start is attempted. Circulation of the cooling fluid within the tank 62 may be improved by suitably arranging discharge nozzles (not shown) within the tank 62. By this arrangement, cool down time of the rotor rim 60 can be reduced substantially so that multiple starts can be made within a relatively short time without risk of rotor damage.
It will now be apparent that the invention provides a robust motor assembly which includes a continuous solid rim and a water tank for transferring heat energy therefrom. Bar expansion problems due to differential heating of the rotor are avoided in the continuous solid rim construction. The large heat capacity of the cooling fluid disposed in heat transfer relation with the inside diameter of the rim insures that the temperature of the rim will be held reasonably uniform and that the stresses will be maintained sufficiently below the yield point of the rim material for multiple starts within a relatively short time period.
Although a particular embodiment of the invention has been shown and described for the purpose of illustration, it will be apparent that other embodiments and modifications are possible within the scope of the invention.
|
A large starting motor is provided, especially for reversible, pumped storage water wheel generator-motor units, having a rotor member which comprises a relatively thin ferromagnetic rim and a closed container of cooling fluid disposed adjacent and radially inward thereof. Heat developed due to circulation of starting currents within the rim is conducted to the cooling fluid through the inside diameter surface of the rotor rim. Provision is made for venting and replenishing the cooling fluid which heats up and in extreme cases vaporizes in response to the thermal energy transferred from the rim.
| 7
|
FIELD OF THE INVENTION
This invention relates to detergent bleaching compositions containing ligand compounds, and to methods of bleaching and cleaning substrates, especially fabric substrates, using such compositions. In particular, the present invention is concerned with compounds comprising a pentadentate ligand, for use with peroxygen bleaching agents.
BACKGROUND OF THE INVENTION
Peroxygen bleaching agents have been known for many years and are used in a variety of industrial and domestic bleaching and cleaning processes. The activity of such agents is, however, extremely temperature-dependent, and drops off sharply at temperatures below 60° C. Especially for cleaning fabrics, high temperature operation is both economically undesirable and practically disadvantageous.
One approach to solving this problem has been through the additional use of so-called bleach activators, also known as bleach precursors. These activators typically are carboxylic acid esters that react with hydrogen peroxide anions in aqueous liquor to generate the corresponding peroxyacid which, in turn, oxidises the substrate. However, these activators are not catalytic. Once the activator has been perhydrolysed, it can no longer be recycled and, therefore, it is usually necessary to use relatively high levels of activator. Since bleach activators are relatively expensive, the cost of using activators at such levels may be prohibitive.
Another approach has been to use transition metal complexes as catalysts to activate the peroxy bleaching agent. For example, U.S. Pat. No. 4,728,455 discloses the use of manganese(III)-gluconate as a peroxide bleach catalyst with high hydrolytic and oxidative stability. In EP-A-0,458,379, for example, triazacyclononane-based manganese complexes are disclosed that display a high catalytic oxidation activity at low temperatures, which is particularly suitable for bleaching purposes.
In WO-A-9534628, it has been shown that the use of iron complexes containing certain pentadentate nitrogen-containing ligands, in particular N,N-bis(pyridin-2-ylmethyl)-bis(pyridin-2-yl)methylamine ("N 4 Py"), as bleaching and oxidation catalysts, resulted in favourable bleaching and oxidation activity. However, the synthesis of this ligand is relatively costly.
WO-A-9718035 discloses iron and manganese complexes containing ligands such as N,N'-bis(pyridin-2-ylmethyl)ethylene-1,2-diamine ("Bispicen"), N-methyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine ("TrispicMeen"), and N,N,N',N'-tetrakis(pyridin-2-ylmethyl)ethylene-1,2-diamine ("TPEN"), as peroxide oxidation catalysts for organic substrates.
WO-A-9748787 relates to iron complexes having polydentate ligands containing at least six nitrogen or oxygen hetero atoms, the metal ion being coordinated by at least five hetero atoms, for example 1,1,4,8,11,11-hexa(pyridin-2-ylmethyl)-1,4,8,11-tetra-aza-undecane ("Hptu"), as catalysts for peroxide, peroxyacid and molecular oxygen bleaching and oxidation.
Whilst known transition metal complexes have to an extent been used successfully as catalysts in detergent bleaching compositions, there remains a need for other such compositions that preferably are more effective in terms of activity or cost.
We have now surprisingly found that a significant or improved catalytic activity can be achieved in a detergent bleaching composition by using a compound having a pentadentate ligand comprising substituted or unsubstituted heteroaryl groups. Furthermore, we have found that compounds providing such activity in detergent bleaching compositions can be produced by easily accessible syntheses.
SUMMARY OF THE INVENTION
Accordingly, in one aspect, the present invention provides a detergent bleaching composition comprising:
a peroxy bleaching compound;
a surface-active material; and
a compound of the general formula (A):
[{M'.sub.a L}.sub.b X.sub.c ].sup.z Y.sub.q (A)
in which
M' represents hydrogen or a metal selected from Ti, V, Co, Zn, Mg, Ca, Sr, Ba, Na, K, and Li;
X represents a coordinating species;
a represents zero or an integer in the range from 0 to 5;
b represents an integer in the range from 1 to 4, preferably 1 to 2;
c represents zero or an integer in the range from 0 to 4;
z represents the charge of the compound and is an integer which can be positive, zero or negative;
Y represents a counter ion, the type of which is dependent on the charge of the compound;
q=z/[charge Y];
L represents a pentadentate ligand of general formula (B):
R.sup.1 R.sup.1 N--W--NR.sup.1 R.sup.2 (B)
wherein
each R 1 independently represents --R 3 --V, in which R 3 represents optionally substituted alkylene, alkenylene, oxyalkylene, aminoalkylene or alkylene ether, and V represents an optionally substituted heteroaryl group selected from pyridinyl, pyrazinyl, pyrazolyl, imidazolyl, benzimidazolyl, pyrimidinyl, triazolyl and thiazolyl;
W represents an optionally substituted alkylene bridging group selected from --CH 2 CH 2 --, --CH 2 CH 2 CH 2 --, --CH 2 CH 2 CH 2 CH 2 --, and --CH 2 --C 6 H 4 --CH 2 --;
R 2 represents a group selected from alkyl and aryl, optionally substituted with a substituent selected from hydroxy, alkoxy, carboxylate, carboxamide, carboxylic ester, sulphonate, amine, alkylamine or N + (R 4 ) 3 , wherein R 4 is selected from hydrogen, alkanyl, alkenyl, arylalkanyl, arylalkenyl, oxyalkanyl, oxyalkenyl, aminoalkanyl, aminoalkenyl, alkanyl ether and alkenyl ether.
The peroxy bleaching compound is preferably selected from hydrogen peroxide, hydrogen peroxide-liberating or -generating compounds, peroxyacids and their salts, and mixtures thereof. Preferably, the composition further comprises peroxyacid bleach precursors.
Preferably, the composition further comprises a detergency builder.
Advantageously, the compounds used in accordance with the invention have been found to provide favourable stain removal in the presence of hydrogen peroxide or peroxyacids. Also, an improved bleaching activity has been noted, particularly in alkaline aqueous solutions containing peroxy compounds at concentrations generally present in the wash liquor during the fabric washing cycle.
DETAILED DESCRIPTION OF THE INVENTION
Generally, detergent bleaching composition according to the invention may be used in the washing and bleaching of substrates including laundry, dishwashing and hard surface cleaning. Alternatively, the detergent bleaching composition of the invention may be used for bleaching in the textile, paper and woodpulp industries, as well as in waste water treatment.
As already stated, an advantage of the compounds used in accordance with the present invention is that they can provide a remarkably high oxidation activity in alkaline aqueous media in the presence of peroxy compounds.
A second advantage is that they show good bleaching activity at a broader pH range (generally pH 6-11) than observed in previously disclosed detergent bleaching compositions. Their performance was especially improved at pH of around 10. This advantage may be particularly beneficial in view of the current detergent formulations that employ rather alkaline conditions, as well as the tendency to shift the pH during fabric washing from alkaline (typically, a pH of 10) to more neutral values. Furthermore, this advantage may be beneficial when using the present compositions in machine dishwash formulations.
Another advantage is that the compounds used in the detergent bleaching compositions of the invention have a relatively low molecular weight and, consequently, are very weight-effective.
The ligand L, having the general formula R 1 R 1 N--W--NR 1 R 2 as defined above, is a pentadentate ligand. By `pentadentate` herein is meant that five hetero atoms can potentially coordinate to a metal ion, of which two hetero atoms are linked by the bridging group W and one coordinating hetero atom is contained in each of the three R 1 groups. Preferably, the coordinating hetero atoms are nitrogen atoms.
The ligand L comprises at least one heteroaryl group in each of the three R 1 groups. Preferably, the heteroaryl group is substituted, more preferably is a substituted pyridin-2-yl group, and still more preferably is a methyl- or ethyl-substituted pyridin-2-yl group linked to an N atom in the above formula via a methylene group. More preferably, the heteroaryl group is a 3-methyl-pyridin-2-yl group linked to an N atom via methylene.
The group R 2 is a substituted or unsubstituted alkyl, aryl or arylalkyl group, provided that R 2 is different from each of the groups R 1 in the formula above. Suitable substituents are selected from hydroxy, alkoxy, carboxylate, carboxamide, carboxylic ester, sulphonate, amine, alkylamine and N + (R 4 ) 3 , wherein R 4 is selected from hydrogen, alkanyl, alkenyl, arylalkanyl, arylalkenyl, oxyalkanyl, oxyalkenyl, aminoalkanyl, aminoalkenyl, alkanyl ether and alkenyl ether. Preferably, R 2 is methyl, ethyl, benzyl, 2-hydroxyethyl or 2-methoxyethyl. More preferably, R 2 is methyl or ethyl.
The bridging group W may be a substituted or unsubstituted alkylene group selected from --CH 2 CH 2 --, --CH 2 CH 2 CH 2 --, --CH 2 CH 2 CH 2 CH 2 --, and --CH 2 --C 6 H 4 --CH 2 -- (wherein --C 6 H 4 -- can be ortho-, para-, or meta-C 6 H 4 --). Preferably, the bridging group is an ethylene or 1,4-butylene group, more preferably an ethylene group.
Examples of preferred ligands in their simplest forms are:
N-methyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-hydroxyethyl)-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-methoxyethyl)-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-methyl-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-hydroxyethyl)-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-methoxyethyl)-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-methyl-N,N',N'-tris(5-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(5-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(5-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-hydroxyethyl)-N,N',N'-tris(5-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-methoxyethyl)-N,N',N'-tris(5-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-methyl-N,N',N'-tris(3-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(3-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(3-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-hydroxyethyl)-N,N',N'-tris(3-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-methoxyethyl)-N,N',N'-tris(3-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-methyl-N,N',N'-tris(5-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(5-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(5-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine; and
N-(2-hydroxyethyl)-N,N',N'-tris(5-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-methoxyethyl)-N,N',N'-tris(5-ethyl-pyridin-2-ylmethyl)ethylene-1,2-diamine.
N-methyl-N,N',N'-tris(3,5-dimethyl-pyrazol-1-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(3,5-dimethyl-pyrazol-1-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(3,5-dimethyl-pyrazol-1-ylmethyl)ethylene-1,2-diamine;
N-(2-hydroxyethyl)-N,N',N'-tris(3,5-dimethyl-pyrazol-1-ylmethyl)ethylene-1,2-diamine;
N-(2-methoxyethyl)-N,N',N'-tris(3,5-dimethyl-pyrazol-1-ylmethyl)ethylene-1,2-diamine;
N-methyl-N,N',N'-tris(1-methyl-benzimidazol-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(1-methyl-benzimidazol-2-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(1-methyl-benzimidazol-2-ylmethyl)ethylene-1,2-diamine;
N-(2-hydroxyethyl)-N,N',N'-tris(1-methyl-benzimidazol-2-ylmethyl)ethylene-1,2-diamine;
N-(2-methoxyethyl)-N,N',N'-tris(1-methyl-benzimidazol-2-ylmethyl)ethylene-1,2-diamine;
More preferred ligands are:
N-methyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-hydroxyethyl)-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-methoxyethyl)-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-methyl-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-benzyl-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-(2-hydroxyethyl)-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine; and
N-(2-methoxyethyl)-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine.
The most preferred ligands are:
N-methyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-ethyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine;
N-methyl-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine; and
N-ethyl-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine.
N-(2-hydroxyethyl)-N,N',N'-tris(3-methyl-pyridin-2-ylmethyl)ethylene-1,2-diamine;
The compounds used in accordance with the invention may include suitable counter ions to balance the charge z on the compound formed by the ligand L and atoms M'. Thus, if the charge z is positive, Y may be an anion such as R 6 COO - , BPh 4 - , ClO 4 - , BF 4 - , PF 6 - , R 6 SO 3 - , R 6 SO 4 - , SO 4 2- , NO 3 - , F - , Cl - , Br - , or I - , with R 6 being H, optionally substituted alkyl or optionally substituted aryl. If z is negative, Y may be a common cation such as an alkali metal, alkaline earth metal or (alkyl)ammonium cation.
Suitable counter ions Y include those which give rise to the formation of storage-stable solids. Preferred counter ions for the preferred compounds are selected from R 6 COO - , ClO 4 - , BF 4 - , PF 6 - , R 6 SO 3 - (in particular CF 3 SO 3 - ), R 6 SO 4 - , SO 4 2- , NO 3 - , F - , Cl - , Br - , and I - , with R 6 being hydrogen, optionally substituted phenyl, naphthyl or C 1 -C 4 alkyl.
Suitable coordinating species X may be selected from R 5 OH, NR 5 3 , R 5 CN, R 5 OO - , R 5 S - , R 5 O - , R 5 COO - , OCN - , SCN - , N 3 - , CN - , F - , Cl - , Br - , I - , O 2- , O 2 2- , O 2 - , NO 3 - , NO 2 - , SO 4 2- , SO 3 2- , PO 4 3- and aromatic N donors selected from pyridines, pyrazines, pyrazoles, imidazoles, benzimidazoles, pyrimidines, triazoles and thiazoles, with R 5 being selected from hydrogen, optionally substituted alkyl and optionally substituted aryl. X may also be the species LM'O - or LM'OO - , wherein M' and L are as defined above. Preferred coordinating species X are CH 3 CN, H 2 O, F - , Cl - , Br - , OOH - , O 2 2- , O 2 - , LM'O - , LM'OO - , R 5 COO - and R 5 O - wherein R 5 represents hydrogen or optionally substituted phenyl, naphthyl, or C 1 -C 4 alkyl.
The effective level of the compound, expressed in terms of parts per million (ppm) of ligand L in an aqueous detergent bleaching solution, will normally range from 0.001 ppm to 100 ppm, preferably from 0.01 ppm to 20 ppm, most preferably from 0.05 ppm to 10 ppm. Higher levels may be desired and applied in industrial bleaching processes, such as textile and paper pulp bleaching. The lower range levels are preferably used in domestic laundry operations.
In an embodiment of the present invention, the detergent bleaching composition is in admixture with a salt, or salt mixture, of a transition metal M. The metal M is preferably selected from iron (Fe), manganese (Mn) and copper (Cu), and combinations thereof. More preferably, the metal is Fe or Mn, and most preferably is Fe. In this embodiment, the metal M salt and compound are present in the mixture in such form that they do not produce a metal M-ligand complex during storage of the composition before use. Preferably, the metal salt and compound are in the form of discrete solids, for example as separate, optionally coated powders, particles or granules in dry mixture, or as discrete components within the same granule. Suitable processes for providing the metal salt and compound in the form of discrete solids, such as by spray drying, are known in the art.
The composition of the invention is preferably activated for use in detergent bleaching of a suitable substrate. For example, the composition can be mixed with a solution containing metal M ions, or containing any species that can provide metal M ions, to form an activated wash liquor. Alternatively, the composition can be applied to substrates containing metal M ions, for example fabrics soiled or stained with metal M-containing soils or stains. This may be particularly desirable for soil or stain targeted bleaching. Alternatively, if the composition already contains salts of metal M ions in a form discrete from the compound, then activation can be effected by dissolution of the composition in a suitable solvent, preferably in aqueous solution, for example in wash water, to form a wash liquor.
The Peroxy Bleaching Compound
The peroxy bleaching compound may be any compound which is capable of yielding hydrogen peroxide in aqueous solution, including hydrogen peroxide and hydrogen peroxide adducts. Hydrogen peroxide sources are well known in the art. They include the alkali metal peroxides, organic peroxides such as urea peroxide, and inorganic persalts, such as the alkali metal perborates, percarbonates, perphosphates, persilicates and persulphates. Mixtures of two or more such compounds may also be suitable.
Particularly preferred are sodium perborate tetrahydrate and, especially, sodium perborate monohydrate. Sodium perborate monohydrate is preferred because of its high active oxygen content. Sodium percarbonate may also be preferred for environmental reasons. The amount thereof in the composition of the invention usually will be within the range of about 2 to 35% by weight, preferably from 10 to 25% by weight.
Another suitable hydrogen peroxide generating system is a combination of a C 1 -C 4 alkanol oxidase and a C 1 -C 4 alkanol, especially a combination of methanol oxidase (MOX) and ethanol. Such combinations are disclosed in WO-A-9507972, which is incorporated herein by reference. A further suitable hydrogen peroxide generating system uses a combination of glucose oxidase and glucose.
Alkylhydroxy peroxides are another class of suitable peroxy bleaching compounds. Examples of these materials include cumene hydroperoxide and t-butyl hydroperoxide.
Organic peroxyacids are also suitable as peroxy bleaching compounds. Such materials normally have the general formula: ##STR1## wherein R is an alkylene or alkyl- or alkylidene-substituted alkylene group containing from 1 to about 20 carbon atoms, optionally having an internal amide linkage; or a phenylene or substituted phenylene group; and Y is hydrogen, halogen, alkyl, aryl, an imido-aromatic or non-aromatic group, a --COOH or --COOOH group or a quaternary ammonium group.
Typical monoperoxyacids useful herein include, for example:
(i) peroxybenzoic acid and ring-substituted peroxybenzoic acids, e.g. peroxy-α-naphthoic acid;
(ii) aliphatic, substituted aliphatic and arylalkyl monoperoxyacids, e.g. peroxylauric acid, peroxystearic acid and N,N-phthaloylaminoperoxy caproic acid (PAP); and
(iii) 6-octylamino-6-oxo-peroxyhexanoic acid.
Typical diperoxyacids useful herein include, for example:
(iv) 1,12-diperoxydodecanedioic acid (DPDA);
(v) 1,9-diperoxyazelaic acid;
(vi) diperoxybrassylic acid; diperoxysebacic acid and diperoxyisophthalic acid;
(vii) 2-decyldiperoxybutane-1,4-dioic acid; and
(viii) 4,4'-sulphonylbisperoxybenzoic acid.
Also suitable are inorganic peroxyacid compounds such as, for example, potassium monopersulphate (MPS). If organic or inorganic peroxyacids are used as the peroxygen compound, the amount thereof will normally be within the range of about 2 to 10% by weight, preferably from 4 to 8% by weight.
Generally, the detergent bleaching composition of the invention can be suitably formulated to contain from 2 to 35%, preferably from 5 to 25% by weight, of the peroxy bleaching compound.
All these peroxy compounds may be utilized either alone or in conjunction with a peroxyacid bleach precursor and/or an organic bleach catalyst not containing a transition metal.
Peroxyacid bleach precursors are known and amply described in literature, such as in the GB-A-0,836,988; GB-A-0,864,798; GB-A-0,907,356; GB-A-1,003,310 and GB-A-1,519,351; DE-A-3,337,921; EP-A-0,185,522; EP-A-0,174,132; EP-A-0,120,591; and U.S. Pat. No. 1,246,339; U.S. Pat. No. 3,332,882; U.S. Pat. No. 4,128,494; U.S. Pat. No. 4,412,934 and U.S. Pat. No. 4,675,393.
Another useful class of peroxyacid bleach precursors is that of the cationic i.e. quaternary ammonium substituted peroxyacid precursors as disclosed in U.S. Pat. No. 4,751,015 and U.S. Pat. No. 4,397,757, in EP-A-0,284,292 and EP-A-0,331,229. Examples of peroxyacid bleach precursors of this class are:
2-(N,N,N-trimethyl ammonium)ethyl sodium-4-sulphophenyl carbonate chloride--(SPCC);
N-octyl-N,N-dimethyl-N 10 -carbophenoxy decyl ammonium chloride--(ODC);
3-(N,N,N-trimethyl ammonium) propyl sodium-4-sulphophenyl carboxylate; and
N,N,N-trimethyl ammonium toluyloxy benzene sulphonate.
A further special class of bleach precursors is formed by the cationic nitriles as disclosed in EP-A-0,303,520; EP-A-0,458,396 and EP-A-0,464,880.
Any one of these peroxyacid bleach precursors can be used in the present invention, though some may be more preferred than others. Of the above classes of bleach precursors, the preferred classes are the esters, including acyl phenol sulphonates and acyl alkyl phenol sulphonates; the acyl-amides; and the quaternary ammonium substituted peroxyacid precursors including the cationic nitriles.
Examples of the preferred peroxyacid bleach precursors or activators are sodium-4-benzoyloxy benzene sulphonate (SBOBS); N,N,N'N'-tetraacetyl ethylene diamine (TAED); sodium-1-methyl-2-benzoyloxy benzene-4-sulphonate; sodium-4-methyl-3-benzoyloxy benzoate; 2-(N,N,N-trimethyl ammonium)ethyl sodium-4-sulphophenyl carbonate chloride (SPCC); trimethyl ammonium toluyloxy-benzene sulphonate; sodium nonanoyloxybenzene sulphonate (SNOBS); sodium 3,5,5-trimethyl hexanoyl-oxybenzene sulphonate (STHOBS); and the substituted cationic nitrites.
The precursors may be used in an amount of up to 12%, preferably from 2 to 10% by weight, of the composition.
The ligand-containing compound of formula (A) will be present in the detergent bleach composition of the invention in amounts so as to provide the required level in the wash liquor. Generally, the amount of compound in the detergent bleach composition is from 0.0005% to 0.5% by weight. When the dosage of detergent bleach composition is relatively low, e.g. about 1 to 2 g/l, the amount of compound in the formulation is suitably 0.001 to 0.5%, preferably 0.002 to 0.25% by weight. At higher product dosages, as used for example by European consumers, the amount of compound in the formulation is suitably 0.0002 to 0.1%, preferably 0.0005 to 0.05% by weight.
Detergent bleach compositions of the invention are effective over a wide pH-range of between 7 and 13, with optimal pH-range lying between 8 and 11.
The Surface-Active Material
The detergent bleach composition according to the present invention generally contains a surface-active material in an amount of from 10 to 50% by weight. The surface-active material may be naturally derived, such as soap, or a synthetic material selected from anionic, nonionic, amphoteric, zwitterionic, cationic actives and mixtures thereof. Many suitable actives are commercially available and are fully described in the literature, for example in "Surface Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch.
Typical synthetic anionic surface-actives are usually water-soluble alkali metal salts of organic sulphates and sulphonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl portion of higher aryl radicals. Examples of suitable synthetic anionic detergent compounds are sodium and ammonium alkyl sulphates, especially those obtained by sulphating higher (C 8 -C 18 ) alcohols produced, for example, from tallow or coconut oil; sodium and ammonium alkyl (C 9 -C 20 ) benzene sulphonates, particularly sodium linear secondary alkyl (C 10 -C 15 ) benzene sulphonates; sodium alkyl glyceryl ether sulphates, especially those ethers of the higher alcohols derived from tallow or coconut oil fatty acid monoglyceride sulphates and sulphonates; sodium and ammonium salts of sulphuric acid esters of higher (C 9 -C 18 ) fatty alcohol alkylene oxide, particularly ethylene oxide, reaction products; the reaction products of fatty acids such as coconut fatty acids esterified with isethionic acid and neutralised with sodium hydroxide; sodium and ammonium salts of fatty acid amides of methyl taurine; alkane monosulphonates such as those derived by reacting alpha-olefins (C 8 -C 20 ) with sodium bisulphite and those derived by reacting paraffins with SO 2 and Cl 2 and then hydrolysing with a base to produce a random sulphonate; sodium and ammonium (C 7 -C 12 ) dialkyl sulphosuccinates; and olefin sulphonates, which term is used to describe material made by reacting olefins, particularly (C 10 -C 20 ) alpha-olefins, with SO 3 and then neutralising and hydrolysing the reaction product. The preferred anionic detergent compounds are sodium (C 10 -C 15 ) alkylbenzene sulphonates, and sodium (C 16 -C 18 ) alkyl ether sulphates.
Examples of suitable nonionic surface-active compounds which may be used, preferably together with the anionic surface-active compounds, include, in particular, the reaction products of alkylene oxides, usually ethylene oxide, with alkyl (C 6 -C 22 ) phenols, generally 5-25 EO, i.e. 5-25 units of ethylene oxides per molecule; and the condensation products of aliphatic (C 8 -C 18 ) primary or secondary linear or branched alcohols with ethylene oxide, generally 2-30 EO. Other so-called nonionic surface-actives include alkyl polyglycosides, sugar esters, long-chain tertiary amine oxides, long-chain tertiary phosphine oxides and dialkyl sulphoxides.
Amphoteric or zwitterionic surface-active compounds can also be used in the compositions of the invention but this is not normally desired owing to their relatively high cost. If any amphoteric or zwitterionic detergent compounds are used, it is generally in small amounts in compositions based on the much more commonly used synthetic anionic and nonionic actives.
The detergent bleach composition of the invention will preferably comprise from 1 to 15% wt of anionic surfactant and from 10 to 40% by weight of nonionic surfactant. In a further preferred embodiment, the detergent active system is free from C 16 -C 12 fatty acid soaps.
The Detergency Builder
The detergent bleach composition of the invention preferably also contains a detergency builder in an amount of from about 5 to 80% by weight, preferably from about 10 to 60% by weight.
Builder materials may be selected from 1) calcium sequestrant materials, 2) precipitating materials, 3) calcium ion-exchange materials and 4) mixtures thereof.
Examples of calcium sequestrant builder materials include alkali metal polyphosphates, such as sodium tripolyphosphate; nitrilotriacetic acid and its water-soluble salts; the alkali metal salts of carboxymethyloxy succinic acid, ethylene diamine tetraacetic acid, oxydisuccinic acid, mellitic acid, benzene polycarboxylic acids, citric acid; and polyacetal carboxylates as disclosed in U.S. Pat. No. 4,144,226 and U.S. Pat. No. 4,146,495.
Examples of precipitating builder materials include sodium orthophosphate and sodium carbonate.
Examples of calcium ion-exchange builder materials include the various types of water-insoluble crystalline or amorphous aluminosilicates, of which zeolites are the best known representatives, e.g. zeolite A, zeolite B (also known as zeolite P), zeolite C, zeolite X, zeolite Y and also the zeolite P-type as described in EP-A-0,384,070.
In particular, the compositions of the invention may contain any one of the organic and inorganic builder materials, though, for environmental reasons, phosphate builders are preferably omitted or only used in very small amounts. Typical builders usable in the present invention are, for example, sodium carbonate, calcite/carbonate, the sodium salt of nitrilotriacetic acid, sodium citrate, carboxymethyloxy malonate, carboxymethyloxy succinate and water-insoluble crystalline or amorphous aluminosilicate builder materials, each of which can be used as the main builder, either alone or in admixture with minor amounts of other builders or polymers as co-builder.
It is preferred that the composition contains not more than 5% by weight of a carbonate builder, expressed as sodium carbonate, more preferably not more than 2.5% by weight to substantially nil, if the composition pH lies in the lower alkaline region of up to 10.
Other Ingredients
Apart from the components already mentioned, the detergent bleach composition of the invention can contain any of the conventional additives in amounts of which such materials are normally employed in fabric washing detergent compositions. Examples of these additives include buffers such as carbonates, lather boosters, such as alkanolamides, particularly the monoethanol amides derived from palmkernel fatty acids and coconut fatty acids; lather depressants, such as alkyl phosphates and silicones; anti-redeposition agents, such as sodium carboxymethyl cellulose and alkyl or substituted alkyl cellulose ethers; stabilizers, such as phosphonic acid derivatives (i.e. Dequest® types); fabric softening agents; inorganic salts and alkaline buffering agents, such as sodium sulphate and sodium silicate; and, usually in very small amounts, fluorescent agents; perfumes; enzymes, such as proteases, cellulases, lipases, amylases and oxidases; germicides and colourants.
When using a hydrogen peroxide source, such as sodium perborate or sodium percarbonate, as the bleaching compound, it is preferred that the composition contains not more than 5% by weight of a carbonate buffer, expressed as sodium carbonate, more preferable not more than 2.5% by weight to substantially nil, if the composition pH lies in the lower alkaline region of up to 10.
Of the additives, transition metal sequestrants such as EDTA, and phosphonic acid derivatives such as EDTMP (ethylene diamine tetra(methylene phosphonate)) are of special importance, as not only do they improve the stability of the catalyst/H 2 O 2 system and sensitive ingredients, such as enzymes, fluorescent agents, perfumes and the like, but also improve the bleach performance, especially at the higher pH region of above 10, particularly at pH 10.5 and above.
The invention will now be further illustrated by way of the following non-limiting examples:
EXAMPLES
Synthesis:
All reactions were performed under a nitrogen atmosphere, unless indicated otherwise. All reagents and solvents were obtained from Aldrich or Across and used as received, unless stated otherwise. Petroleum ether 40-60 was distilled using a rotavapor before using it as eluent. Flash column chromatography was performed using Merck silica gel 60 or aluminium oxide 90 (activity II-III according to Brockmann). 1 H NMR (300 MHz) and 13 C NMR (75 MHz) were recorded in CDCl 3 , unless stated otherwise. Multiplicities were addressed with the normal abbreviations using p for quintet.
Synthesis of Starting Materials for Ligand Synthesis:
Synthesis of N-benzyl amino acetonitrile. N-benzyl amine (5.35 g, 50 mmol) was dissolved in a water:methanol mixture (50 mL, 1:4). Hydrochloric acid (aq., 30%) was added until the pH reached 7.0. Added was NaCN (2.45 g, 50 mmol). After cooling to 0° C., formaline (aq. 35%, 4.00 g, 50 mmol) was added. The reaction was followed by TLC (aluminium oxide; EtOAc:Et 3 N=9:1) until benzylamine could be detected. Subsequently the methanol was evaporated in vacuo and the remaining oil "dissolved" in water. The aqueous phase was extracted with methylene chloride (3×50 mL). The organic layers were collected and the solvent removed in vacuo. The residue was purified by Kugelrohr distillation (p=20 mm Hg, T=120° C.) giving N-benzyl amino acetonitrile (4.39 g, 30 mmol, 60%) as a colourless oil.
1 H NMR: δ7.37-7.30 (m, 5H), 3.94 (s, 2H), 3.57 (s, 2H), 1.67 (br s, 1H);
13 C NMR: δ137.74, 128.58, 128.46, 128.37, 127.98, 127.62, 117.60, 52.24, 36.19.
Synthesis of N-ethyl amino acetonitrile. This synthesis was performed analogously to the synthesis reported for N-benzyl amino acetonitrile. However, detection was done by dipping the TLC plate in a solution of KMnO 4 and heating the plate until bright spots appeared. Starting from ethylamine (2.25 g, 50 mmol), pure N-ethyl amino acetonitrile (0.68 g, 8.1 mmol, 16%) was obtained as a slightly yellow oil.
1 H NMR: δ3.60 (s, 2H), 2.78 (q, J=7.1, 2H), 1.22 (br s, 1H), 1.14 (t, J=7.2, 3H);
13 C NMR: δ117.78, 43.08, 37.01, 14.53.
Synthesis of N-ethyl ethylene-1,2-diamine. The synthesis was performed according to Hageman; J.Org.Chem.; 14; 1949; 616, 634, starting from N-ethyl amino acetonitrile.
Synthesis of N-benzyl ethylene-1,2-diamine. Sodium hydroxide (890 mg; 22.4 mmol) was dissolved in ethanol (96%, 20 mL), the process taking the better part of 2 hours. Added was N-benzyl amino acetonitrile (4, 2.92 g, 20 mmol) and Raney Nickel (approx. 0.5 g). Hydrogen pressure was applied (p=3.0 atm.) until hydrogen uptake ceased. The mixture was filtered over Cellite, washing the residue with ethanol. The filter should not run dry since Raney Nickel is relatively pyrophoric. The Cellite containing the Raney Nickel was destroyed by putting the mixture in dilute acid, causing gas formation). The ethanol was evaporated in in vacuo and the residue dissolved in water. Upon addition of base (aq. NaOH, 5N) the product oiled out and was extracted with chloroform (3×20 mL). After evaporation of the solvent in vacuo the 1 H NMR showed the presence of benzylamine. Separation was enforced by column chromatography (silica gel; MeOH:EtOAc:Et 3 N=1:8:1) yielding the benzyl amine, followed by the solvent mixture MeOH:EtOAc:Et 3 N=5:4:1. Detection was done by using aluminium oxide as a solid phase in TLC, yielding pure N-benzyl ethylene-1,2-diamine (2.04 g, 13.6 mmol, 69%).
1 H NMR: δ7.33-7.24 (m, 5H), 3.80 (s, 2H), 2.82 (t, J=5.7, 2H), 2.69 (t, J=5.7, 2H), 1.46 (br s, 3H);
13 C NMR: δ140.37, 128.22, 127.93, 126.73, 53.73, 51.88, 41.66.
Synthesis of 2-acetoxymethyl-5-methyl pyridine. 2,5-Lutidine (31.0 g, 290 mmol), acetic acid (180 mL) and hydrogen peroxide (30 mL, 30%) were heated at 70-80° C. for 3 hours. Hydrogen peroxide (24 mL, 30%) was added and the subsequent mixture heated for 16 hours at 60-70° C. Most of the mixture of (probably) hydrogen peroxide, water, acetic acid, and peracetic acid was removed in vacuo (rotavap, water bath 50° C. until p=20 mbar). The resulting mixture containing the N-oxide was added dropwise to acetic anhydride heated under reflux. This reaction was highly exothermic, and was controlled by the dropping speed. After heating under reflux for an hour, methanol was added dropwise. This reaction was highly exothermic. The resulting mixture was heated under reflux for another 30 minutes. After evaporation of the methanol (rotavap, 50° C. until p=20 mbar), the resulting mixture was purified by Kugelrohr distillation (p=20 mm Hg, T=150° C.). The clear oil that was obtained still contained acetic acid. This was removed by extraction (CH 2 Cl 2 , NaHCO 3 (sat.)) yielding the pure acetate of 2-acetoxymethyl-5-methyl pyridine (34.35 g, 208 mmol, 72%) as a slightly yellow oil.
1 H NMR: δ8.43 (s, 1H), 7.52 (dd, J=7.8, J=1.7, 1H), 7.26 (d, J=7.2, 1H), 5.18 (s, 2H), 2.34 (s, 3H), 2.15 (s, 3H);
13 C NMR: δ170.09, 152.32, 149.39, 136.74, 131.98, 121.14, 66.31, 20.39, 17.66.
Synthesis of 2-acetoxymethyl-5-ethyl pyridine. This synthesis was performed analogously to the synthesis reported for 2-acetoxymethyl-5-methyl pyridine. Starting from 5-ethyl-2-methyl pyridine (35.10 g, 290 mmol), pure 2-acetoxymethyl-5-ethyl pyridine (46.19 g, 258 mmol, 89%) was obtained as a slightly yellow oil.
1 H NMR: δ8.47 (s, 1H), 7.55 (d, J=7.8, 1H), 7.29 (d, J=8.1, 1H), 2.67 (q, J=7.8, 2H), 2.14 (s, 3H), 1.26 (t, J=7.77, 3H);
13 C NMR: δ170.56, 152.80, 149.11, 138.47, 135.89, 121.67, 66.72, 25.65, 20.78, 15.13.
Synthesis of 2-acetoxymethyl-3-methyl pyridine. This synthesis was performed analogously to the synthesis reported for 2-acetoxymethyl-5-methyl pyridine. The only difference was the reversal of the Kugelrohr distillation and the extraction. According to 1 H NMR a mixture of the acetate and the corresponding alcohol was obtained. Starting from 2,3-picoline (31.0 g, 290 mmol), pure 2-acetoxymethyl-3-methyl pyridine (46.19 g, 258 mmol, 89%, calculated for pure acetate) was obtained as a slightly yellow oil.
1 H NMR: δ8.45 (d, J=3.9, 1H), 7.50 (d, J=8.4, 1H), 7.17 (dd, J=7.8, J=4.8, 1H), 5.24 (s, 2H), 2.37 (s, 3H), 2.14 (s, 3H).
Synthesis of 2-hydroxymethyl-5-methyl pyridine. 2-Acetoxymethyl-5-methyl pyridine (30 g, 182 mmol) was dissolved in hydrochloric acid (100 mL, 4 N). The mixture was heated under reflux, until TLC (silica gel; triethylamine:ethyl acetate:petroleum ether 40-60=1:9:19) showed complete absence of the acetate (normally 1 hour). The mixture was cooled, brought to pH>11, extracted with dichloromethane (3×50 mL) and the solvent removed in vacuo. Pure 2-hydroxymethyl-5-methyl pyridine (18.80 g, 152 mmol, 84%) was obtained by Kugelrohr distillation (p=20 mm Hg, T=130° C.) as a slightly yellow oil.
1 H NMR: δ8.39 (s, 1H), 7.50 (dd, J=7.8, J=1.8, 1H), 7.15 (d, J=8.1, 1H), 4.73 (s, 2H), 3.83 (br s, 1H), 2.34 (s, 3H);
13 C NMR: δ156.67, 148.66, 137.32, 131.62, 120.24, 64.12, 17.98.
Synthesis of 2-hydroxymethyl-5-ethyl pyridine. This synthesis was performed analogously to the synthesis reported for 2-hydroxymethyl-5-methyl pyridine. Starting from 2-acetoxymethyl-5-ethyl pyridine (40 g, 223 mmol), pure 2-hydroxymethyl-5-ethyl pyridine (26.02 g, 189 mmol, 85%) was obtained as a slightly yellow oil.
1 H NMR: δ8.40 (d, J=1.2, 1H), 7.52 (dd, J=8.0, J=2.0, 1H), 7.18 (d, J=8.1, 1H), 4.74 (s, 2H), 3.93 (br s, 1H), 2.66 (q, J=7.6, 2H), 1.26 (t, J=7.5, 3H);
13 C NMR: δ156.67, 148.00, 137.87, 136.13, 120.27, 64.07, 25.67, 15.28.
Synthesis of 2-hydroxymethyl-3-methyl pyridine. This synthesis was performed analogously to the synthesis reported for 2-hydroxymethyl-5-methyl pyridine. Starting from 2-acetoxymethyl-3-methyl pyridine (25 g (recalculated for the mixture), 152 mmol), pure 2-hydroxymethyl-3-methyl pyridine (15.51 g, 126 mmol, 83%) was obtained as a slightly yellow oil.
1 H NMR: δ8.40 (d, J=4.5, 1H)), 7.47 (d, J=7.2, 1H), 7.15 (dd, J=7.5, J=5.1, 1H), 4.85 (br s, 1H), 4.69 (s, 1H), 2.22 (s, 3H);
13 C NMR: δ156.06, 144.97, 137.38, 129.53, 121.91, 61.38, 16.30.
Synthesis of Ligands:
Synthesis of N-methyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylene-1,2-diamine (L1). The ligand L1 (comparative) was prepared according to Bemal, Ivan; Jensen, Inge Margrethe; Jensen, Kenneth B.; McKenzie, Christine J.; Toftlund, Hans; Tuchagues, Jean-Pierre; J.Chem.Soc.Dalton Trans.; 22; 1995; 3667-3676.
Synthesis of N-methyl-N,N',N'-tris(3-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L2, Me-TRILEN). 2-Hydroxymethyl-3-methyl pyridine (5.00 g, 40.7 mmol) was dissolved in dichloromethane (30 mL). Thionyl chloride (30 mL) was added dropwise under cooling (ice bath). The resulting mixture was stirred for 1 hour and the solvents removed in vacuo (rotavap, until p=20 mm Hg, T=50° C.). To the resultant mixture was added dichloromethane (25 mL). Subsequently NaOH (5 N, aq.) was added dropwise until the pH (aqua)≧11. The reaction was quite vigorous in the beginning, since part of the thionyl chloride was still present. N-methyl ethylene-1,2-diamine (502 mg, 6.8 mmol) and additional NaOH (5 N, 10 mL) were added. The reaction mixture was stirred at room temperature for 45 hours. The mixture was poured into water (200 mL), and the pH checked (≧14, otherwise addition of NaOH (aq. 5N)). The reaction mixture was extracted with dichloromethane (3 or 4×50 mL, until no product could be detected by TLC). The combined organic phases were dried and the solvent removed in vacuo. Purification was enforced as described before, yielding N-methyl-N,N',N'-tris(3-methylpyridin-2-ylmethyl)ethylene-1,2-diamine as a slightly yellow oil. Purification was enforced by column chromatography (aluminium oxide 90 (activity II-III according to Brockmann); triethylamine:ethyl acetate:petroleum ether 40-60=1:9:10) until the impurities were removed according to TLC (aluminium oxide, same eluent, Rf≈0.9). The compound was eluted using ethylacetate:triethyl amine=9:1. N-methyl-N',N'-tris(3-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L2, 1.743 g, 4.30 mmol, 63%) was obtained.
1 H NMR: δ8.36 (d, J=3.0, 3H), 7.40-7.37 (m, 3H), 7.11-7.06 (m, 3H), 3.76 (s, 4H), 3.48 (s, 2H), 2.76-2.71 (m, 2H), 2.53-2.48 (m, 2H), 2.30 (s, 3H), 2.12 (s, 6H), 2.05 (s, 3H);
13 C NMR: δ156.82, 156.77, 145.83, 145.67, 137.61, 133.14, 132.72, 122.10, 121.88, 62.32, 59.73, 55.19, 51.87, 42.37, 18.22, 17.80.
Synthesis of N-ethyl-N,N',N'-tris(3-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L3, Et-TRILEN). This synthesis is performed analogously to the synthesis for L2. Starting from 2-hydroxymethyl-3-methyl pyridine (25.00 g, 203 mmol) and N-ethyl ethylene-1,2-diamine (2.99 g, 34.0 mmol), N-ethyl-N,N',N'-tris(methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L3, 11.49 g, 28.5 mmol, 84%) was obtained. Column chromatography (aluminium oxide; Et 3 N:EtOAc:petroleum ether 40-60=1:9:30, followed by Et 3 N:EtOAc=1:9).
1 H NMR: δ8.34-8.30 (m, 3H), 7.40-7.34 (m, 3H), 7.09-7.03 (m, 3H), 3.71 (s, 4H), 3.58 (s, 2H), 2.64-2.59 (m, 2H), 2.52-2.47 (m, 2H), 2.43-2.36 (m, 2H), 2.31 (s, 3H), 2.10 (s, 6H), 0.87 (t, J=7.2, 3H);
13 C NMR: δ157.35, 156.92, 145.65, 137.61, 133.14, 132.97, 122.09, 121.85, 59.81, 59.28, 51.98, 50.75, 48.02, 18.27, 17.80, 11.36.
Synthesis of N-benzyl-N,N',N'-tris(3-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L4, Bn-TRILEN). This synthesis is performed analogously to the synthesis for L2. Starting from 2-hydroxymethyl-3-methylpyridine (3.00 g 24.4 mmol), and N-benzyl ethylene-1,2-diamine (610 mg, 4.07 mmol), N-benzyl-N,N'N'-tris(3-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L4, 1.363 g, 2.93 mmol, 72%) was obtained. Column chromatography (aluminium oxide; Et 3 N:EtOAc:petroleum ether 40-60=1:9:10).
1 H NMR: δ8.33-8.29 (m, 3H), 7.37-7.33 (m, 3H), 7.21-7.03 (m, 8H), 3.66 (s, 4H), 3.60 (s, 2H), 3.42 (s, 2H), 2.72-2.67 (m, 2H), 2.50-2.45 (m, 2H), 2.23 (s, 3H), 2.03 (s, 6H);
13 C NMR: δ157.17, 156.96, 145.83, 145.78, 139.29, 137.91, 137.80, 133.45, 133.30, 128.98, 127.85, 126.62, 122.28, 122.22, 59.99, 58.83, 51.92, 51.54, 18.40, 17.95.
Synthesis of N-hydroxyethyl-N,N',N'-tris(3-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L5). This synthesis is performed analogously to the synthesis for L6. Starting from 2-hydroxymethyl-3-methyl pyridine (3.49 g, 28.4 mmol), and N-hydroxyethyl ethylene-1,2-diamine (656 mg 6.30 mmol), after 7 days N-hydroxyethyl-N,N',N'-tris(3-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L5, 379 mg, 0.97 mmol, 14%) was obtained.
1 H NMR: δ8.31-8.28 (m, 3H), 7.35-7.33 (m, 3H), 7.06-7.00 (m, 3H), 4.71 (br s, 1H), 3.73 (s, 4H), 3.61 (s, 2H), 3.44 (t, J=5.1, 2H), 2.68 (s, 4H), 2.57 (t, J=5.0, 2H), 2.19 (s, 3H), 2.10 (s, 6H);
13 C NMR: δ157.01, 156.88, 145.91, 145.80, 137.90, 137.83, 133.30, 131.89, 122.30, 121.97, 59.60, 59.39, 57.95, 56.67, 51.95, 51.22, 18.14, 17.95.
Synthesis of N-methyl-N,N',N'-tris(5-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L6). 2-hydroxymethyl-5-methyl pyridine (2.70 g, 21.9 mmol) was dissolved in dichloromethane (25 mL). Thionyl chloride (25 mL) was added dropwise under cooling (ice bath). The resulting mixture was stirred for 1 hour and the solvents removed in vacuo (rotavap, until p=20 mm Hg, T±35° C.). The remaining oil was used directly in the synthesis of the ligands, since it was known from the literature that the free picolyl chlorides are somewhat unstable and are highly lachrymatory. To the resultant mixture was added dichloromethane (25 mL) and N-methyl ethylene-1,2-diamine (360 mg, 4.86 mmol). Subsequently NaOH (5 N, aq.) was added dropwise. The reaction was quite vigorous in the beginning, since part of the thionyl chloride was still present. The aqueous layer was brought to pH=10, and additional NaOH (5 N, 4.38 mL) was added. The reaction mixture was stirred until a sample indicated complete conversion (7 days). The reaction mixture was extracted with dichloromethane (3×25 mL). The combined organic phases were dried and the solvent removed in vacuo. Purification was enforced by column chromatography (aluminium oxide 90 (activity II-III according to Brockmann); triethylamine:ethyl acetate:petroleum petroleum ether 40-60=1:9:10) until the impurities were removed according to TLC (aluminium oxide, same eluent, Rf≈0.9). The compound was eluted using ethyl acetate:triethyl amine=9:1, yielding N-methyl-N,N',N'-tris(5-methylpyridin-2-ylmethyl)ethylene-1,2-diamine (L6, 685 mg, 1.76 mmol, 36%) as a slightly yellow oil.
1 H NMR: δ8.31 (s, 3H) 7.43-7.35 (m, 5H), 7.21 (d,J=7.8, 1H), 3.76 (s, 4H), 3.56 (s, 2H), 2.74-2.69 (m, 2H), 2.63-2.58 (m, 2H), 2.27 (s, 6H), 2.16 (s, 3H);
13 C NMR: δ156.83, 156.43, 149.23, 149.18, 136.85, 136.81, 131.02, 122.41, 122.30, 63.83, 60.38, 55.53, 52.00, 42.76, 18.03.
Synthesis of N-methyl-N,N',N'-tris(5-ethylpyridin-2-ylmethyl)ethylene-1,2-diamine (L7). This synthesis is performed analogously to the synthesis for L6. Starting from 2-hydroxymethyl-5-ethyl pyridine (3.00 g, 21.9 mmol), and N-methyl ethylene-1,2-diamine (360 mg, 4.86 mmol), after 7 days N-methyl-N,N',N'-tris(5-ethylpyridin-2-ylmethyl)ethylene-1,2-diamine (L7, 545 mg, 1.26 mmol, 26%) was obtained.
1 H NMR: δ8.34 (s, 3H), 7.44-7.39 (m, 5H), 7.26 (d, J=6.6, 1H), 3.80 (s, 4H), 3.59 (s, 2H), 2.77-2.72 (m, 2H), 2.66-2.57 (m, 8H), 2.18 (s, 3H), 1.23 (t, J=7.5, 9H);
3 C NMR: δ157.14, 156.70, 148.60, 148.53, 137.25, 135.70, 122.59, 122.43, 63.91, 60.48, 55.65, 52.11, 42.82, 25.73, 15.36.
Experimental:
Experiments were carried out in a temperature-controlled glass beaker equipped with a magnetic stirrer, thermocouple and a pH electrode. The bleach experiments are carried out at 40 and 60° C. In examples when formulations are used, the dosage amounted to about 5 g/l total formulation. The composition of the base formulation without bleach is described below:
______________________________________Detergent formulation:______________________________________Anionic surfactant: 9% Nonionic surfactant: 7% Soap: 1% Zeolite: 30% Polymers: 3% Sodium carbonate: 7% Enzyme granules: 1% Sodium silicate: 5% Sodium citrate: 3.5% Dequest ® 2047: 1% Percarbonate: 19% TAED granule (83%) 5.5% Water and minors: 8%______________________________________
In total 8.6 mmol/1 H 2 O 2 was used, dosed in the form of sodium percarbonate. The pH was adjusted at 10.0. The bleaching process took place for 30 minutes.
Tea-stained test cloths (BC-1) were used as bleach monitor. After the bleach experiment, the cloths were rinsed in tap water and dried in a tumble drier. The reflectance (R 460 *) was measured before and after the wash on a Minolta® CM 3700d spectrophotometer. The average was taken of 2 test cloths. The differences in reflectance, expressed as ΔR values, are given in the tables below.
Example 1
An iron perchlorate solution (4 ml ethanol) was first added to 800 ml percarbonate buffer (8.7 mmol/1) pH 10 solution (yielding 8.7 mmol/1 hydrogen peroxide and 10 μM Fe solution) that contains two BC-1 cloths. Subsequently, a ligand solution (4 ml ethanol) was added. After 30 minutes at 40° C. (pH 10.2) the bleach results were as follows:
______________________________________ ΔR:______________________________________Blank (no ligand): 9.0 points with ligand L2 (45 μM): 14.4 points with ligand L3 (43 μM): 12.3 points______________________________________
Example 2
The same procedure was carried out as in Example 1, but in a detergent formulation containing percarbonate (no TAED) in a representative wash liquor: 10 μM Fe, 4.7 μM Cu, 0.3 μM Zn, pH 9.9:
______________________________________ ΔR:______________________________________Blank (no ligand): 9.2 points with ligand L2 (45 μM): 11.9 points with ligand L3 (43 μM): 10.0 points______________________________________
These results show that bleach activation in a detergent composition can be effective using free ligands in accordance with the invention, without the need for premixing of metal salts with the ligands or the dosing of well-defined metal-ligand complexes.
The structures of the ligands L1 to L7 is shown below: ##STR2##
|
A detergent bleaching composition is provided comprising a compound inclug a specified pentadentate nitrogen-containing ligand. The compound can activate hydrogen peroxide or peroxyacids and provides favourable stain removal properties, particularly in the presence or iron, manganese or copper ions. In addition, an improved stability in alkaline aqueous environment has been obtained, in particular at the peroxy compound concentrations generally present in the fabric washing liquor.
| 2
|
This application claims priority under 35 U.S.C. 119 to patent application Ser. No. 2000-105484 filed Apr. 6, 2000 in Japan, the content of which is incorporated hereinto by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to communication quality acquisition apparatuses and methods employed in cellular mobile communication systems using spread signals such as CDMA(Code Division Multiple Access), and more specifically, to an apparatus and a method for acquiring communication quality through the CDMA pilot channel in the service area.
2. Description of the Related Art
In the prior art communication method that divides a given band into several channels and then conducts communications through such channels, the communication quality is affected by thermal noise caused by decrease in receiving power and interference noise in the co-channel and adjacent channels caused by the reuse of spatially the co-channel and adjacent channels. Then, its communication quality is identified by measuring the receiving power of the channel sent from the operating base station. Such receiving power can be measured by extracting the signal spectrum in each desired channel by the use of frequency converters and frequency selection filters and then measuring the power provided from each filter.
However, in the case of the CDMA method, which is regarded as the most promising one among the future mobile communication methods, the acquisition of communication quality in the service area should be conducted in a different way.
In the CDMA method, since the allocated band is not divided into several channels but shared by all the communication channels, those channels are distinguished from each other with different codes. Therefore, in order to receive signals in a given channel for the acquisition of communication quality, the code assigned to each channel must be identified and synchronization must be established by detecting the code interval. Because a number of channels are required to be measured at the same time for the acquisition of communication quality, a parallel data processing is necessary for code synchronization. Further, since the CDMA method improves communication quality by using a wide band, the delay profile, which is two-dimensional data, must be acquired for the acquisition of communication quality. Then, the CDMA method poses such problems that its data processing becomes very complicated when implementing code synchronization over a number of channels to acquire communication quality and that the amount of data increases along with the acquisition of delay profile.
Delay during code synchronization causes failed data acquisition and thus lowers the code synchronization accuracy. It also leads to a problem of extended “measurement window”, which is the time interval for the measurement of delay profile. As a result, the amount of data processing grows during measurement and the portion of meaningful data in the acquired data decreases. In addition, such an increase in the data amount caused by the acquisition of delay profile shortens the meaning data acquisition time, thus lowering the processing efficiency.
SUMMARY OF THE INVENTION
This invention has been made to solve the above problems and its object is, therefore, to provide an apparatus and a method for quick and efficient acquisition of communication quality. For this purpose, the invention realizes a quick code synchronization, through control of a code synchronization unit and a delay profile measurement unit, over a number of channels handled in parallel by conducting measurement using the CDMA pilot channel in the service area where the mobile communication services are provided by code-spread methods like CDMA. Then the improvements of code synchronization accuracy and speed enable to efficiently detect meaningful delay profile. In addition, the measurement window can be narrowed and the delay profile acquisition process is optimized. As a result, the amount of data to be acquired is reduced so that the communication quality may be acquired efficiently.
In the first invention, a communication quality acquisition apparatus receives the CDMA pilot channels sent from a plurality of wireless base stations through the use of spread signals different from each other and has an acquisition means for acquiring delay profile based on the spread signals in the CDMA pilot channels and a storage means for storing the delay profile acquired by the acquisition means. This configuration enables to reduce the amount of necessary data and thereby efficiently acquire communication quality.
In the second invention, the acquisition means according to the first invention has a synchronization means for establishing synchronization based on the spread signals in the CDMA pilot channels, a measurement means for acquiring delay profile by reverse spreading the spread signals in the CDMA pilot channels and a control means for controlling the synchronization means and measurement means. This configuration enables to conduct the synchronization detection for a plurality of CDMA channels and their re-synchronization in parallel at a time and at a high efficiency.
In the third invention, the storage means according to the first invention attaches the information of time and location to the delay profile acquired by the acquisition means and stores the information in the storage means.
In the fourth invention, the control means according to the second invention controls the synchronization means and measurement means based on the conditions set by the user for initial error detection check, re-synchronization of each mode, off-track check and automatic re-synchronization check, or on information set for the code to be measured. This configuration enables to reduce fails in data acquisition due to delays that occur during code synchronization. Then meaningful data is not missed and the necessary amount of data can be minimized.
In the fifth invention, the control means according to the second invention controls the measurement means based on the synchronization point information acquired by the synchronization means. This configuration enables to narrow the width of the “measurement window”, which is the time interval for measurement of delay profile.
In the sixth invention, the control means according to the second invention controls the synchronization means based on the check results of initial error detection, automatic re-synchronization or off-track acquired by the measurement means. This configuration enables to raise accuracy in detecting synchronization points and to know the exact location of meaningful delay profile.
The seventh invention is a communication quality acquisition method comprising: the step of receiving CDMA channels sent from a plurality of wireless base stations through the use of spread signals different from each other; the acquisition step of acquiring delay profile based on the spread signals in the CDMA channels; and the storage step of storing the delay profile acquired by the acquisition step. This method enables to reduce the amount of necessary data and acquire communication quality efficiently.
In the eighth invention, the acquisition step according to the seventh invention comprises: the step of establishing synchronization based on the spread signals in the CDMA pilot channels; the measurement step of acquiring delay profile by reverse spreading the spread signals in the CDMA pilot channels; and the control step of controlling the synchronization step and measurement step. This method enables to conduct synchronization detection for a plurality of CDMA channels and their re-synchronization in parallel at a time and at a high efficiency.
In the ninth invention, at the storage step according to the seventh invention, the information of time and location is attached to the delay profile acquired at the acquiring step and then stored at the storage step.
In the tenth invention, at the control step according to the seventh invention, the synchronization step and measurement step are controlled based on the conditions set by the user for initial error detection check, re-synchronization of each mode, off-track check and automatic re-synchronization check, or on information set for the code that will be measured. This method enables to reduce the failure in data acquisition due to delay during code synchronization. Then meaningful data is not missed and the necessary amount of data can be minimized.
In the eleventh invention, the control step according to the eighth invention controls the measurement step based on the synchronization point information acquired at the synchronization step. This method enables to narrow the width of “measurement window”, which is the time interval for measurement of delay profile.
In the twelfth invention, the control step according to the eighth invention controls the synchronization step based on the check results of initial error detection, automatic re-synchronization or off-track. This method enables to raise accuracy in detecting synchronization points and to know the exact location of meaningful delay profile.
The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating an example of the communication quality acquisition apparatus according to the present invention;
FIG. 2 is a schematic diagram illustrating the control process in the delay profile measurement unit shown in FIG. 1 ;
FIG. 3A shows a schematic diagram illustrating the reception of a CDMA pilot channel sent from a specific base station;
FIG. 3B shows an example of delay profile;
FIG. 4 is a flow chart illustrating an example of the method for acquiring delay profile when the communication quality acquisition apparatus according to the invention receives a CDMA pilot channel sent from a given base station;
FIG. 5 is a schematic diagram illustrating an example of the synchronization point detection process that the synchronization unit executes during the initial detection process shown in FIG. 4 ;
FIG. 6 is a schematic diagram illustrating an example of acquiring delay profile provided by the measurement unit according to the invention;
FIG. 7A is a schematic diagram illustrating an example of acquiring delay profile;
FIG. 7B is a flow chart illustrating an example of how to check the initial error detection shown in FIG. 4 ;
FIG. 8A is a schematic diagram illustrating an example of acquiring delay profile;
FIG. 8B is a flow chart illustrating an example of how to check the off-track shown in FIG. 4 ;
FIG. 9A is a schematic diagram illustrating an example of acquiring delay profile;
FIG. 9B is a flow chart illustrating an example of how to check the automatic re-synchronization shown in FIG. 4 ;
FIG. 10 is a diagram illustrating how to use the detection requested code list and detection completed code list according to the invention;
FIGS. 11A to 11 D are diagrams illustrating examples of the measurement code settings, detection requested code list and detection completed code list according to the invention;
FIG. 12 is a diagram showing the relationship of FIGS. 12A and 12B ;
FIGS. 12A and 12B are flow charts illustrating examples of the synchronization point detection for the case where the re-synchronization mode is set at the automatic re-synchronization and an example of the synchronization detection process;
FIG. 13 is a diagram showing the relationship of FIGS. 13A and 13B ;
FIGS. 13A and 13B are flow charts illustrating examples of the synchronization point detection for the case where the re-synchronization mode is set at the automatic re-synchronization and an example of the re-synchronization detection process;
FIG. 14 is a diagram showing the relationship of FIGS. 14A and 14B ;
FIGS. 14A and 14B are flow charts illustrating examples of the synchronization point detection for the case where the re-synchronization mode is set at the manual re-synchronization and an example of the synchronization detection;
FIG. 15 is a diagram showing the relationship of FIGS. 15A and 15B ;
FIGS. 15A and 15B are flow charts illustrating examples of the synchronization point detection for the case where the re-synchronization mode is set at the manual re-synchronization and an example of the re-synchronization detection; and
FIGS. 16A and 16B are diagrams illustrating examples of the output provided halfway during measurement according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a block diagram illustrating an example of the communication quality acquisition apparatus according to the present invention. The communication quality acquisition apparatus 100 has a delay profile acquisition unit 111 and a storage unit 112 . The communication quality acquisition apparatus 100 receives CDMA pilot channels sent from base stations (base station A, B, C) of different codes (codes A, B, C) at one time. The delay profile acquisition unit 111 further comprises a synchronization unit 121 , a measurement unit 122 and a control unit 123 . The control unit 123 controls the synchronization unit 121 and the measurement unit 122 .
FIG. 2 is a schematic diagram illustrating the control process in the delay profile measurement unit 111 shown in FIG. 1 . The control process executed by the control unit 123 uses measurement code setting information, re-synchronization mode setting conditions, off-track check conditions, initial error detection check conditions, and automatic re-synchronization check conditions, which are all determined by the user. Also used are synchronization point information obtained by the synchronization unit 121 , and initial error detection check results, automatic re-synchronization check results and off-track check results obtained by the measurement unit 122 .
FIG. 3A shows a schematic diagram illustrating the reception of a CDMA pilot channel sent from a specific base station. Since communication quality is improved by using a wide band in the CDMA method, the acquisition of the delay profile is important. FIG. 3B shows an example of delay profile. The delay profile is the electric power level of radio waves which are drawn along the delay time of each radio wave arriving at a receiving point in multiplexed propagation paths. In order to acquire delay profile, it is necessary to detect the code used in the CDMA pilot channel and its repetition timing in advance and then establish code synchronization. Code synchronization has to be established for every CDMA channel that is to be measured. Further, code synchronization must be implemented not only at the beginning of measurement but also during measurement each time the measurement window is renewed and off-track takes place.
The amount of acquired data should be minimized to prevent data growth resulting from the acquisition of the delay profile that is two-dimensional data. The width of the measurement window must be optimized. This can be optimized by increasing the frequency of code synchronization and refreshing the measurement window to narrow the measurement window. Only meaningful data of delay profile is thereby stored.
FIG. 4 shows an example of the method for acquiring delay profile when the communication quality acquisition apparatus receives a CDMA pilot channel sent from a specific base station. When the communication quality acquisition apparatus starts operation, the synchronization unit 121 detects the synchronization point and conducts the initial acquisition of the code used in the CDMA pilot channel (S 401 ). Next, initial error detection check is executed to determine whether the obtained initial error detection is the right one or not by the measurement unit 122 (S 402 ). If it is determined as a failure by this initial error detection check, the initial detection will be redone. If it is determined as successful, the mode of re-synchronization is read (S 403 ) to conduct different operations based on the specified mode.
If the re-synchronization mode is set at “automatic”, the measurement (S 404 ) proceeds along with the off-track check (S 405 ), measurement completion check (S 406 ) and automatic re-synchronization check (S 407 ). If an off-track is detected in the off-track check (S 405 ), the operation returns to the initial detection (S 401 ). If an automatic re-synchronization is determined to do by the automatic re-synchronization check (S 407 ), the current synchronization point is maintained, data measurement and storage are implemented, while the automatic re-synchronization (S 408 ) is carried out to detect a new synchronization point.
On the other hand, if the re-synchronization mode is set at “manual”, the measurement (S 411 ) is conducted along with the manual re-synchronization order check (S 412 ) and the measurement completion check (S 413 ). The above measurement operation (S 411 ) is continued until an order for manual re-synchronization is issued. When a manual re-synchronization order is issued, the operation returns to the initial detection (S 401 ).
FIG. 5 shows an example of the synchronization point detection that the synchronization unit executes during the initial detection (S 401 ) shown in FIG. 4 . During the synchronization point detection, the correlation between the received signal and the reference signal for each code is provided by a correlation examination. However, only one correlation result is given during each code interval because the code synchronization has not been established. The synchronization point is identified by, for example, the location presenting the strongest correlation for each code and provided to the detection completed code list (described later) as an output given halfway in the synchronization process.
FIG. 6 shows an example of acquiring delay profile by the measurement method. The measurement unit 122 provides the degree of correlation for each code based on the synchronization point information indicated by the output given halfway in the synchronization process. Now that code synchronization has been established, correlation is given for each portion of the partial correlation intervals. This output of correlation is digitized to meet the form suitable for data storage. Later, it will be correlated with measurement time to form a pair of path level corresponding to delay time. The delay profile is thereby provided as an output given halfway in the measurement process.
FIG. 7B shows an example of the initial error detection check (S 402 ) shown in FIG. 4 . After the initialization of the check time (S 701 ), the delay profile is observed (S 702 ) as an output given halfway in the measurement process. If a path is detected that exceeds the initial detection threshold during the operation of determining whether there is a path exceeding the initial detection threshold (S 703 ), the initial error detection is determined as successful (S 704 ). If there is no path detected that exceeds the initial detection threshold, the check time is incremented (S 705 ), and the check time and the initial detection protection time are compared with each other (S 706 ). The initial error detection is determined as a failure (S 707 ), if the check time is equal to or longer than the initial detection protection time, namely, only if the period of no path that exceeds the initial detection threshold is equal to or longer than the initial detection protection time. Note that the initial detection threshold and the initial detection protection time are parameters that the user is allowed to determine as the initial error detection check conditions.
FIG. 8B shows an example of the off-track detection check (S 405 ) shown in FIG. 4 . After the initialization of the check time (S 801 ), the delay profile is observed (S 802 ) as an output given halfway in the measurement process. If a path is detected that exceeds the path selection level during the operation of determining whether there is a path exceeding the path selection level (S 803 ), the check time is initialized (S 804 ) and it is determined that an off-track did not occur (S 805 ). If there is no path detected that exceeds the path selection level, the check time is incremented (S 806 ), and the check time and the off-track detection protection time are compared with each other (S 807 ). It is determined that an off-track has occurred (S 808 ), if the check time is equal to or longer than the off-track protection time, in other words, if the period of no path that exceeds the path selection level is equal to or longer than the off-track protection time. Note that the path selection level and the off-track protection time are parameters that are set by the user as the off-track check conditions.
FIG. 9B shows an example of the automatic re-synchronization check (S 407 ) shown in FIG. 4 . After the initialization of the check time (S 901 ), the delay profile is observed (S 902 ) as an output given halfway in the measurement process. Next, the path level weighted average delay time is calculated (S 903 ) and it is determined whether it exceeds the width of the one-side re-synchronization window or not (S 904 ). Further, it is also determined whether the sum of the path levels exceeds the automatic re-synchronization threshold or not (S 905 ). If either answer is NO, the check time is initialized (S 906 ) and it is determined that the automatic re-synchronization will not be conducted (S 907 ). If both answers are YES, the check time is incremented (S 908 ) and compared with the automatic re-synchronization protection time (S 909 ).
It is determined that the automatic re-synchronization will be carried out (S 910 ) if the check time is equal to or longer than the automatic re-synchronization protection time, in other words, if the pulse level weighted average delay time exceeds the width of the one-side re-synchronization window and the existent period of path where the sum of path levels exceeds the automatic re-synchronization threshold is equal to or longer than the automatic re-synchronization protection time. Note that the width of the one-side re-synchronization window, the automatic re-synchronization threshold and the automatic re-synchronization protection time are parameters that can be set by the user as the automatic re-synchronization check conditions.
FIG. 10 shows the method using a detection requested code list and a detection completed code list. In order to receive and handle the signals sent from more than one base station through CDMA pilot channels in parallel at a time, the detection requested code list and the detection completed code list are used. FIG. 10 demonstrates how the three operations, namely, the synchronization point detection operation conducted in the synchronization unit 121 , initial error detection check operation in the measurement unit 122 and re-synchronization check operation (manual, automatic, off-track) in the measurement unit 122 , and the detection requested code list and detection completion code list are related with one another.
First, the detection requested code list is initialized by the measurement code settings determined by the user. The measurement code settings describe the numbers of the codes that will be measured, names of the base stations as reference information and search numbers for list scanning. The detection requested code list is the code list of the codes that will be detected. The listed codes are referred to, from their top on the list, by the synchronization unit 121 for synchronization point detection. The code of which detection has been completed is removed from the detection requested code list and then transferred to the detection completion code list. The descriptions of the detection completed code list are the same as those of the detection requested code list except that the information about synchronization points is added in the completed code list.
The measurement unit 122 conducts initial error detection on the codes described in the detection completed code list. If the initial error detection is determined as a failure, the corresponding code is removed from the detection completed code list and then transcribed on the detection requested code list so that the operation is returned to the synchronization unit 121 . If the initial error detection is determined as successful, the storage operation begins in the measurement unit 122 and re-synchronization check operation starts. The code for which re-synchronization starts is removed from the detection completed code list for re-synchronization according to the setting, either of manual, automatic or on-track. Afterward, it is transferred to the detection requested code list and the operation is returned to the synchronization unit 121 . If the mode of re-synchronization check is set at “automatic”, the synchronization detection must be made with the current data measurement being continued. Thus the code is described on the detection requested code list, while it remains in the detection completed code list.
FIGS. 11A to 11 D show examples of the measurement code settings, detection requested code list and detection completed code list. FIG. 11A shows the example of measurement code settings, where a user has specified eight codes with the code numbers 3 , 6 , 9 , 55 , 120 , 378 , 412 , 501 . FIG. 11B shows a detection requested code list that has been initialized according to the measurement code settings. FIG. 11C shows the state of a detection requested code list after the detentions of code 3 and code 6 have been completed. FIG. 11D shows a detection completed code list. The synchronization point is detected in the order of the search numbers described on the detection requested code list.
FIGS. 12A , 12 B, 13 A and 13 B show examples of the synchronization point detection for the case where the re-synchronization mode is set at the automatic re-synchronization. After the start of operation, the setting of re-synchronization mode is read out (S 1201 ). If its mode is determined to be “automatic”, the processing flow branches to a flow of synchronization detection or the other flow of re-synchronization detection.
FIGS. 12A and 12B show examples of synchronization detection. First, the measurement code settings are read (S 1202 ) and the detection requested code list is initialized (S 1203 ). Next, according to the list search numbers, the codes on the detection requested code list are referred to (S 1205 ) and the detection request is examined (S 1206 ). If there is a detection request code on the list, the detection is started (S 1207 ). When the detection is completed for a code, the code number is removed from the detection requested code list (S 1208 ), the code number and the synchronization point are saved (S 1209 ) in the record of the same search number on the detection completed code list. The scanning of the detection requested code list based on the search number is constantly continued during measurement (S 1211 , S 1212 ). Therefore, if the code number is described on the detection requested code list, its detection is conducted instantaneously. In the figures that follow, X%Y represents the remainder given when X is divided by Y, and && represents logical multiplication.
FIGS. 13A and 13B show examples of the re-synchronization detection operation. First, the initial error detection check condition (S 1301 ), automatic re-synchronization check condition (S 1302 ) and off-track check condition (S 1303 ) are read, and then the detection completed code list is referred to (S 1305 ). Next, it is determined whether detection is completed or not (S 1306 ), and the code of which code number and synchronization point are described on the detection completed code list is subject to the following check.
Namely, based on the check conditions and measurement data, the automatic re-synchronization failure/success check (S 1307 ), initial error detection check (S 1308 ), off-track check (S 1309 ) and automatic re-synchronization check (Sl 310 ) are carried out. If an initial error detect check is carried out, the operation is returned to the detection process after the issue of a measurement cancellation order (S 1311 ), data storage cancellation (S 1312 ), removal from the detection completed code list (S 1313 ), and transfer to the detection requested code list (S 1314 ). The same operations are executed if an off-track check is conducted. When an automatic synchronization check is conducted, the code is listed on the detection requested code list (S 1317 ) and the operation is returned to the detection process, while the current synchronization point (S 1315 ) and data saving (S 1316 ) are continued.
During the check of failure or success in the automatic re-synchronization check (S 1307 ), the initial error detection check at the new synchronization point tells whether or not a new better synchronization point is found under the automatic re-synchronization. If the result of automatic re-synchronization check is YES, the detection completed code list is renewed to a new one for the new synchronization point (S 1318 ), the synchronization point being thereby renewed (S 1319 ). If all the checks have failed and the current synchronization point is determined as the best one, the current synchronization point is maintained (S 1320 ) and data storage starts (S 1321 ).
FIGS. 14A , 14 B, 15 A and 15 B show examples of the synchronization point detection for the case where the re-synchronization mode is set at the manual re-synchronization. After the start of operation, the setting of the re-synchronization mode is read (S 1401 ). If its mode is determined to be set at “manual”, the operation branches to a flow of synchronization detection or the other flow of re-synchronization check.
FIGS. 14A and 14B show examples of the synchronization detection operation. Its flow is all the same as that for the case of the automatic re-synchronization (FIG. 12 A and 12 B).
FIGS. 15A and 15B show examples of the re-synchronization check. First, the initial error detection conditions are read (S 1501 ) and then the detection completed code list is referred to according to the search number (S 1503 ). Next, it is determined whether the detection is over or not (S 1504 ). The code of which code number and synchronization point are described on the detection completed code list is subject to the following check. If a code on the detection completed code list is determined to pass the initial error detection check (S 1505 ) or a manual re-synchronization is ordered (S 1506 ), the measurement (S 1507 ) and data saving (S 1508 ) are canceled. Then the code is removed from the detection completed code list (S 1509 ) and moved to the detection requested code list (S 1510 ) to make the process return to synchronization detection. Unless the code passes those checks, the current synchronization point is maintained (S 1511 ) and data saving (S 1512 ) is continued.
FIGS. 16A and 16B show the examples of an output given halfway in the measurement process according to the invention. FIGS. 16A and 16B demonstrate an output given halfway in the measurement process obtained in parallel for each code as the result of the operations in FIGS. 10 to 15 A and 15 B. In the examples shown in FIGS. 16A and 16B , the output is provided along with the information of time and location. This enhances the effectiveness of the data acquired as delay profile.
The present invention has been described in detail with respect to preferred embodiments, and it will now be apparent from the foregoing to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspect, and it is the intention, therefore, in the apparent claims to cover all such changes and modifications as fall within the true spirit of the invention.
|
In mobile communication systems employing the CDMA method, the communication quality is acquired from the CDMA pilot channel. A communication quality acquisition apparatus comprises a delay profile acquisition unit comprising a control unit, synchronization unit and measurement unit, in addition to a data storage unit. The communication quality is measured by the synchronization unit and the measurement unit which are alternatively controlled by the control unit. When the communication quality is acquired through the CDMA pilot channel, the data acquisition efficiency can be significantly raised.
| 7
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a shift control system of an automatic transmission adapted to appropriately alter a shift characteristic of the automatic transmission.
2. Description of Related Art
Recently commercially available automatic transmissions are generally designed so as to have its shift characteristics altered in an appropriate way. For such automatic transmissions, there are prepared two previously mapped shift characteristics, for example, an economy mode which is mileage-oriented and a power mode which is output-oriented and in which the shift line is set on the side of a high vehicle speed rather than the economy mode, thereby performing a shift control under a desired shift characteristic manually selected.
Japanese Patent Unexamined Publication (kokai) No. 8,983/1982 discloses a shift control system in which the shift characteristic is automatically altered in accordance with the load of the engine. Specifically, the shift control system performs a shift control on the basis of a pre-mapped economy mode at an ordinary driving state, while the shift control system alters the shift control to the output-oriented shift characteristic on the basis of the shift characteristic of the economy mode when the load of the engine is equal to or larger than a predetermined reference value, for example, when a throttle valve is three quarters or more open. The alteration of the shift characteristic forms the shift characteristic for the power mode by altering the shift line for the economy mode to the side of a high vehicle speed in a control circuit on the basis of the shift characteristic of the economy mode. In other words, the load of the engine above the reference value means the requirement for a large output (torque) of the engine, and the output-oriented shift characteristic is automatically set. Further, this conventional technique is such that the shift characteristic is returned from the power mode to the economy mode when the vehicle speed becomes smaller than a predetermined value or a foot brake pedal is depressed.
However, in this conventional technique, the reference value to be used when the shift characteristic is altered is set to a certain constant value, so that the shift characteristic cannot be altered to an appropriate one so as to satisfy the requirement for acceleration by the operator.
This matter will be described more specifically. For instance, when the vehicle is running at a stationary speed with the load of the engine on the orderof a value somewhat exceeding the reference value, the shift characteristic is altered to an output-oriented power mode although the economy mode is preferred from a standpoint of mileage or the like. To the contrary, when the current vehicle speed at which the vehicle is running at a stationary speed is considerably smaller than the load of the engine corresponding to the reference value, the shift characteristic is not altered and it is in the economy mode as it is as long as the load of the engine does not reach the reference value or higher, even if an accelerator pedal is depressed, and no sufficient degree of acceleration can be obtained.
Japanese Patent Unexamined Publication (kokai) No. 22,698/1976 discloses another conventional technique in which the shift line is altered immediately when the accelerator pedal is depressed rapidly.
However, for this conventional technique in which the shift characteristic is altered immediately in accordance with a change rate of the load of the engine, the output-oriented shift characteristic is automatically set because the change rate of the load of the engine becomes too large even if the load of the engine is in an absolutely small range, namely, even if no output (torque) of the engine is required to that large extent. To the contrary, even in a range in which the load of the engine is absolutely large, namely, even when the output (torque) of the engine is required, the mileage-oriented shift characteristic is automatically set due to a small change rate of the load of the engine.
SUMMARY OF THE INVENTION
Therefore, the present invention has the object to provide a shift control system of an automatic transmission for an automotive vehicle, which is adapted so as to appropriately alter a shift characteristic of the automatic transmission in response to the requirement for acceleration by the operator.
Another object of the present invention is to provide a shift control system of an automatic transmission of an automotive vehicle, which is adaptable so as to appropriately alter a shift characteristic of the automatic transmission in response to the requirement for acceleration by the operator, when the shift characteristic is to be altered to an output-oriented shift characteristic when a load of the engine becomes a value equal to or larger than a predetermined value.
In order to achieve the object, the present invention consists of a shift control system of an automatic transmission of an automotive vehicle, comprising:
a load detecting means for detecting a load of an engine;
a load change rate detecting means for detecting a change rate of the load of the engine; and
a shift characteristic altering means for altering a shift characteristic of the automatic transmission in accordance with the load of the engine and the change rate of the load of the engine in response to a signal from said load detecting means and said load change rate detecting means, respectively.
With this arrangement, the shift control system can accurately determine whether the operator actually requires the output (torque) of an engine by taking the change rate of the load of the engine as well as the load of the engine into consideration. As a matter of course, the shift characteristic can be altered to an output-oriented shift characteristic when it is determined that that the operator requires the output of the engine. To the contrary, for instance, when it can be determined that the operator does not require the output of the engine to a very large extent even if the change rate of the load of the engine would be large enough, the automatic transmission may be controlled without altering the shift characteristic.
In order to achieve the second object, the present invention consists of a shift control system of the automatic transmission of the automotive vehicle, comprising:
a load detecting means for detecting a load of an engine;
a shift characteristic altering means for altering a shift characteristic of the automatic transmission from a first shift characteristic to a second shift characteristic which is an output-oriented characteristic more than the first shift characteristic when the load of the engine becomes a value equal to or larger than a predetermined reference value in response to a signal from said load detecting means;
a load change rate detecting means for detecting a change rate of the load of the engine; and
a reference value altering means for altering said reference value to a smaller value in accordance with the change rate of the load of the engine to be detected by said load change rate altering means when the change rate of the load of the engine is larger than when the change rate of the load of the engine is smaller.
This arrangement of the shift control system of the automatic transmission is likely to alter the shift characteristic of the automatic transmission from the mileage-oriented shift characteristic to the output-oriented shift characteristic due to a change of the reference value to a smaller value when the operator depresses the accelerator pedal at a fast speed so as to require a large magnitude of acceleration. Therefore, in instances where the accelerator pedal is depressed at a fast speed so as to reach a region that exceeds the reference value which can be regarded as requiring the output (torque) of the engine, this arrangement allows the shift characteristic to be shifted immediately to the output-oriented shift characteristic. Therefore, the present invention can appropriately alter the shift characteristic of the automatic transmission in correspondence with the requirement for acceleration by the operator.
Other objects, features and advantages of the present invention will become apparent in the course of the description of the preferred embodiments, which follows, in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic representation showing an overall system according to an embodiment of the present invention.
FIG. 2 is a diagram showing a shift characteristic for the economy mode.
FIG. 3 is a diagram showing a shift characteristic for the power mode.
FIG. 4 is a map for setting the power mode.
FIG. 5 is a map for resetting the power mode.
FIGS. 6 and 7 are graphs showing the tendency for setting the power mode as shown in FIG. 4.
FIGS. 8 to 11, inclusive, are graphs showing the tendency for resetting the power mode as shown in FIG. 5.
FIGS. 12A and 12B are flowcharts showing an example of the control according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described more in detail with reference to the accompanying drawings.
As shown in FIG. 1, reference numeral 1 denotes an engine of an Otto type and the output (torque) of the engine 1 is transmitted through an automatic transmission 2 to a driving wheel (not shown).
The automatic transmission 2 in this embodiment comprises a torque converter 3 equipped with a lockup clutch 3A and a multiple shift geartrain mechanism 4 having four forward driving ranges and one rearward driving range. The automatic transmission 2 is of a hydraulically operative type and the lockup clutch 3A is connected or disconnected by exciting or deenergizing a solenoid 5 built in its hydraulic circuit. Further, by changing a combination of excitation with deenergization of a plurality of solenoids 6 built in the hydraulic circuit, the multiple shift geartrain mechanism 4 performs a shift of speed ranges.
Referring to FIG. 1, reference symbol U denotes a control unit for a shift control utilizing a microcomputer. The control unit U receives signals from sensors 21 and 22 and a switch 23 while generating signals to the solenoids 5 and 6. The sensor 21 is to sense an opening angle of a throttle valve. The sensor 22 is to sense a vehicle speed. The switch 23 is to manually select a shift characteristic from four kinds of modes in this embodiment. More specifically, the four kinds of the modes include an economy mode as shown in FIG. 2, a power mode as shown in FIG. 3, an automatic (automatically switching) mode for automatically selecting either of the economy mode or the power mode, and a hold mode. Both of the economy mode as shown in FIG. 2 and the power mode as shown in FIG. 3 are independently and separately mapped. The shift characteristic based on the map for the power mode (FIG. 3) is such that its shift line is set on the high speed side, as compared with a mileage-oriented economy mode, thereby permitting an output-oriented shift. In this embodiment, when the economy mode or the power mode is selected by the switch 23, the shift characteristic is fixed to the mode selected and no change is made. Further, the hold mode is such that, as is known to the state of art, the third speed stage is fixed during speed range D, the second speed stage is fixed during the second speed range, and the first speed stage is fixed during the first speed range. It is noted that the automatic mode is the object for the present invention and that the economy mode is selected at ordinary running state while the economy mode is shifted to the power mode when the load of the engine reaches a reference value or higher. It is further noted that the present invention can be applied to the economy mode selected by the switch 23.
The control by the control unit U will be briefly described. Given the selection of the automatic mode by the switch 23, basically, the economy mode as shown in FIG. 2 is selected and a shift control is performed on the basis of the selected economy mode.
When the throttle valve opening angle TVO indicative of the load of the engine becomes equal to or larger than the predetermined reference value, namely, when the state in which the engine is driven becomes a high-load driving state, the shift characteristic is switched from the economy mode (FIG. 2) to the power mode (FIG. 3), thereby implementing the shift control based on the power mode.
The reference value for switching the shift characteristic to the power mode is determined by a map value which is set by using the vehicle speed, VSP, and the change rate of the throttle valve opening angle, Δ TVO, as parameters as shown in FIG. 4. In FIG. 4, the vehicle speed is indicated as DVSP(J) (J=1, 2, . . . ) while the change rate of the throttle valve opening angle is indicated as DΔ TVO(I) (I=1, 2, . . . ), and the throttle valve opening angle serving as the reference value for switching the shift characteristic is indicated as DTVO(I,J). In other words, when the actual throttle valve opening angle TVO reaches a value equal to or higher than the reference value DTVO(I,J) obtainable by collation with the maps as described hereinabove, the economy mode is switched to the power mode. FIG. 6 shows the correspondence relationship between the change rate of the throttle valve opening angle, Δ TVO, and the reference value DTVO(I,J) when the vehicle speed is set constant in FIG. 4. FIG. 7 shows the correspondence relationship between the vehicle speed VSP and the reference value DTVO(I,J) when the change rate of the throttle valve opening angle is set constant. As is apparent from FIG. 6, the reference value DTVO(I,J) gets smaller as the change rate of the throttle valve opening angle (an increasing rate) gets larger, thereby making it easier to switch the economy mode to the power mode. Further, as is apparent from FIG. 7, the faster the vehicle speed VSP the larger the reference value DTVO(I,J).
The power mode once switched is returned to the economy mode when two conditions are met: one condition is that the vehicle speed becomes larger than a return reference value and the other is that the throttle valve opening angle becomes smaller than a return reference value. In other words, the power mode is returned to the economy mode again when the driving state of the engine is transferred to a stationary driving state. As shown in FIG. 5, the return vehicle speed and the return throttle valve opening angle are stored as map values by using the vehicle speed and the throttle valve opening angle as parameters. In FIG. 5, DVSP(J) (J=1, 2, . . . ) is a vehicle speed for retrieving the map and DXTVO(I) (I=1, 2, . . . ) is a throttle valve opening angle for retrieving the map. And DRTVO(K,J) (K=1, 2, . . . , J=1, 2, . . . ) is a return reference throttle valve opening angle, and DRVSP(K,J)) (K=1, 2, . . . , J=1, 2, . . . ) is a return reference vehicle speed. FIGS. 8 to 11, inclusive, shows the correspondence relationship between the return reference values and the parameters as referenced in FIG. 5. More specifically, FIG. 8 shows the correspondence of the return reference vehicle speed DRVSP(K,J) to the vehicle speed VSP, and the relationship between them is such that the return reference vehicle speed DRVSP(K,J) gets larger as the vehicle speed VSP gets faster. FIG. 9 shows the correspondence of the return reference throttle valve opening angle DRTVO(K,J) to the vehicle speed VSP, and the relationship between them is such that the larger the return reference throttle valve opening angle DRTVO(K,J) the larger the vehicle speed VSP. FIG. 10 indicates the correspondence relationship of the return reference vehicle speed DRVSP(K,J) with respect to the throttle valve opening angle TVO, and the relationship between them is such that the return reference vehicle speed DRVSP(K,J) gets larger as the throttle valve opening angle gets larger. FIG. 11 illustrates the relationship between the return reference throttle valve opening angle DRTVO(K,J) and the throttle valve opening angle TVO, in which the larger the return reference throttle valve opening angle DRTVO(K,J) the larger the throttle valve opening angle TVO.
Then, description will be made of the detail of control by the control unit U in conjunction with FIGS. 12A and 12B.
After the system is started, the system is initialized at step P1 at which a P flag is set to zero. The P flag is arranged such that "1" represents a power mode selection and "0" represents an economy mode selection.
Then, at step P2, the throttle valve opening angle TVO sensed by the sensor 21 and the vehicle speed VSP sensed by the sensor 22 are read, and a change rate, Δ TVO, of the throttle valve opening angle, i.e., a throttle-valve opening-angle change rate, is determined by differentiating the throttle valve opening angle TVO sensed immediately before (by giving the difference from the throttle valve opening angle previously sensed). Then the program flow goes to step P3 at which each of addressess I, J and K on the maps indicated in FIGS. 4 and 5 are set to one.
Thereafter, at step P4, a decision is made to determine if the throttle-valve opening-angle change rate Δ TVO is smaller than the change rate Δ TVO(I) on the map indicated in FIG. 4. If the result of decision at step P4 indicates that the throttle-valve opening-angle change rate Δ TVO is equal to or larger than the change rate Δ TVO(I), then the program flow goes to step P5 at which one is added to I, followed by the return to step P4. This processing is repeated until the change rate Δ TVO becomes smaller than the change rate Δ TVO(I). The processing at steps P4 and P5 is to determine the change rate Δ TVO(I) as shown in FIG. 4 corresponding to the current throttle-valve opening-angle change rate Δ TVO.
When the result of decision at step P4 indicates that the throttle-valve opening-angle change rate Δ TVO is smaller than the change rate Δ TVO(I), the program flow goes to step P6. The processing at step P6 and step P7 is likewise to determine the vehicle speed DVSP(J) shown in FIGS. 4 and 5 corresponding to the current vehicle speed VSP. More specifically, at step P6, a decision is made to determine if the current vehicle speed VSP is smaller than the vehicle speed DVSP(J). If the result of decision at step P6 indicates that the current vehicle speed is equal to or larger than the vehicle speed DVSP(J), on the one hand, the program flow goes to step P7 at which one is added to J, followed by the return to step P6 again. This processing is repeated until the current vehicle speed VSP becomes smaller than the speed DVSP(J).
Then, at step P8, a decision is made to determine if the current throttle valve opening angle TVO is larger than a memory value shown in FIG. 4, i.e., a setting reference value DTVO(I,J), on the basis of the results of the previous processing, DΔ TVO(I) and DVSP(J). If the result of decision at step P8 indicates that the current throttle valve opening angle TVO is larger than the memory value DTVO(I,J), on the one hand, then the program flow proceeds to step P9 at which the P flag is set to one, followed by proceeding to step P21. If it is decided at step P8 that the current throttle valve opening angle TVO is equal to or smaller than the memory value DTVO(I,J), on the other hand, then the program flow proceeds to step P10 at which the P flag is reset to zero, followed by proceeding to step P21.
After step P9 or step P10, the program flow goes to step P21 of FIG. 12B. The processing at step P21 and step P22 of FIG. 12B is to determine the throttle valve opening angle DXTVO(K) shown in FIG. 5 corresponding to the current throttle valve opening angle TVO. More specifically, at step P21, a decision is made to determine if the current throttle valve opening angle TVO is smaller than the throttle valve opening angle DXTVO(K). If it is decided at step P21 that the current throttle opening angle TVO is equal to or larger than the throttle valve opening angle DXTVO(K), then the program flow goes to step P22 at which one is added to K, followed by returning to step P21. This processing is repeated until the current throttle valve opening angle TVO becomes smaller than the throttle opening angle DXTVO(K) and the program flow goes to step P23 when the result of decision at step P21 indicates that the current throttle valve opening angle TVO is smaller than the throttle valve opening angle DXTVO(K).
Then, at step P23, it is decided to determine if the P flag is set to one. When the result of decision at step P23 indicates that the P flag is set to zero, on the one hand, then the program flow goes to step P24 at which the power mode is turned off, followed by the return of the program flow, thereby controlling a shift on the economy mode. On the other hand, when it is decided at step P23 that the P flag is set to one, the program flow proceeds to step P25 at which the power mode is turned on, thereby allowing a shift control on the basis of the power mode.
After the power mode is turned on at step P25, the program flow goes to step P26 from which the processing for determining if the power mode is to be returned to the economy mode is made up to step P29. In other words, at step P26, the current vehicle speed VSP and the current throttle valve opening angle TVO are read, followed by proceeding to step P27 at which a decision is made to determine if the current vehicle speed VSP is larger than the return reference vehicle speed DRVSP(K,J). When the result of decision at step P27 indicates that the current vehicle speed VSP is equal to or smaller than the return reference vehicle speed DRVSP(K,J), on the one hand, the program flow goes back to step P23. When it is decided at step P27 that the current vehicle speed VSP is larger than the return reference vehicle speed DRVSP(K,J), on the other hand, then the program flow goes to step P28 at which a further decision is made to determine whether or not the current throttle valve opening angle TVO is smaller than the return reference throttle valve opening angle DRTVO(K,J). If the result of decision at step P28 indicates that the current throttle valve opening angle TVO is equal to or larger than the return reference throttle valve opening angle DRTVO(K,J), the program flow goes back to step P23. When it is decided at step P28 that the current throttle valve opening angle TVO is smaller than the return reference throttle valve opening angle DRTVO(K,J), the program flow goes to step P29 at which the P flag is reset to zero, thereby returning the power mode to the economy mode, followed by the return of the program flow.
It is to be understood that the present invention has been described by way of examples, however, it can be noted that as the load of the engine, there may be appropriately adopted various ones, such as an accelerator opening angle, an amount of intake air, an amount of fuel injected (particularly in the case of a diesel engine).
It is further to be understood that various other embodiments and variants are possible within the spirit and scope of the invention.
|
A shift characteristic of an automatic transmission is altered in accordance with a load of an engine and a change rate the load of the engine. The shift characteristic may have a power mode and an economy mode, and the shift characteristic is switched between the power mode and the economy mode when the load of the engine becomes a predetermined reference value. When the load of the engine becomes equal to or larger than the reference value, the economy mode is shifted to the power mode. The reference value is changed in accordance with a change rate of the load of the engine, and the reference value becomes smaller as the change rate becomes larger. This construction allows the shift characteristic of the automatic transmission to be altered so as to be appropriate for the requirment by the operation for acceleration.
| 8
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to a method and apparatus for controlling the flow of fluids from a subsurface well, i.e., a well positioned below the surface of the water. More particularly, the present invention provides a method and apparatus for controlling and plugging an undersea oil and/or gas well.
2. Description of the Related Art
In the production of fluids such as petroleum and/or natural gas from subterranean formations, accidents can occur due to human and equipment malfunctions or the like, thereby occasionally producing a condition known as blowout. In such instances, the flow of fluids from a subterranean formation under substantial pressure is unrestricted, with the fluids flowing to the surface, i.e., a sea floor or a land surface. In such instances, it is desirable that a method and apparatus be available for controlling or stopping the flow of such petroleum and/or natural gas because a valuable resource is being wasted and because such fluids pollute the environment when released in an uncontrolled manner.
A number of techniques have been tested and used for controlling the flow of fluids from subterranean formations. For example, U.S. Patent Publication No. US 2002/0162657 A1 discloses a method and apparatus for plugging a well bore using a device to perforate the well casing, and then pumping in cement and squeezing the cement through the perforations and into the formation therearound. U.S. Patent Publication No. US 2009/10277637 A1 discloses a method of plugging and abandonment of an undersea oil well. This method involves severing a well string that extends into an oil well from an oil platform. U.S. Pat. No. 4,417,624 discloses a method and apparatus for controlling the flow of fluids from an offshore oil well involving passing a continuous pipe from a well platform into the open well bore and then pumping a plugging material such as cement into the well bore through the continuous pipe.
In another commonly used method, additional well bores are drilled to intersect with the uncontrolled well bore, so that a plugging fluid such as cement, drilling mud or the like can be pumped into the formation to kill the well. Furthermore, other conventional techniques have involved the use of explosives and the like.
In many instances, blowouts occur during drilling operations. In such instances, it is quite common for the drill ship or drilling rig to move away from the well quickly when the blowout occurs; and in some instances, the drilling rig explodes and is blown away from the well head. As a result, as in the situation with the BP Deepwater Horizon accident, the well bore may be left open at the well head on the ocean floor as a result of equipment malfunction and the like, or at the well head on land. In such instances, the well bore is substantially open so that the flow of petroleum and/or natural gas is unimpeded, thereby resulting in an environmental and economic catastrophe.
Accordingly, it is an object of the present invention to provide a method and apparatus for controlling and/or stopping the control of fluids from such open well bores.
BRIEF SUMMARY OF THE INVENTION
In order to achieve the object of the present invention, the present inventors have endeavored to provide a device and method utilizing same to control/cap a blowout. Accordingly, it has now been unexpectedly discovered that control of the flow of fluids from open well bores fluidly communicating the surface with a subterranean formation can be accomplished by using an apparatus including a fluid control device comprising an elongated round rod (elongated member) having one end with a diameter substantially smaller than the inside diameter of the well bore to be plugged and an opposite end or a portion therebetween with a diameter at least as great as the inside diameter of the well bore.
In a preferred embodiment, the fluid control device comprises a plurality of elongated round sections with a smaller diameter section (elongated member) disposed at one end. The smaller diameter allows for a smaller area upon which the fluid flow can exert forces, which can undesirably deflect the positioning of the remaining sections. This allows for ease in guiding and positioning the elongated member into the well bore casing so that the larger diameter sections of the device can be positioned without them being forced outside of radius of the overflowing pipe section. Further, the elongated member is preferably solid, so as to muffle vibrations and shock waves caused by forces exerted thereon by the fluid flow. The smaller diameter section is preferably connected or formed integrally with an adjacent tapered section.
The adjacent tapered section increases in diameter until the diameter of this tapered section exceeds the inside diameter of the well bore. In an alternative preferred embodiment, the adjacent tapered section has a greatest outside diameter smaller than the inside diameter of the well bore, and is in connection with one or more additional sections, at least one of which has a diameter exceeding the inside diameter of the well bore.
In a preferred embodiment, the fluid control device is formed with a shoulder attached to or formed integral therewith which is operable to come into engagement with the top of the well casing as the fluid control device is lowered into the open well bore. Preferably, the shoulder is greater in diameter than the outside diameter of the well bore casing.
In another preferred embodiment, the diameter of the elongated member is preferably less than about one half, more preferably from about one-tenth to one-half, most preferably from about one-eighth to one-third the diameter of the inside diameter of the well bore to be plugged. By forming the elongated member with a diameter substantially smaller than the inside diameter of the well head casing, resistance to insertion thereof into the well head casing by the fluid flow is greatly decreased.
In another preferred embodiment, the fluid control device is used in conjunction with a support means positioned on the floor of the body of water adjacent the well bore to be plugged. For example, the support means can be positioned on the sea floor over the well head extending from the sea floor. Preferably, an alignment means is positioned on support means above the open well bore, said alignment means being adapted to align the position of the fluid control device over the open well bore as the fluid control device is lowered into the well bore. The mere mass of the fluid control device can be such that it overcomes the forces created by the fluid flowing from the well bore.
Another method of placing and positioning the elongated member (smaller diameter section) of the fluid control device into the well head casing is lowering same from a ship or a drilling platform into engagement with the alignment means, and then into the well bore casing. After the elongated member of the fluid control means is inserted into the well head casing, a tapered section of the fluid control means is then lowered into the well head casing. The adjacent tapered section, or another section above the adjacent tapered section as described above, increases in diameter until the diameter of the fluid control device is equal to the inside diameter of the well head casing.
This gradual differential in diameter along the length of the fluid control device allows for a gradual pressure increase in the outflowing pipe (i.e., the well head casing). By only gradually increasing the pressure during insertion of the fluid control device into the well head casing, the potential of damage to the well head casing is greatly reduced, as there is no downward shock wave propagated, and the “Hoop” pressure is under the yield points of the drill piping).
At this juncture, the downward (gravitational) forces due to the weight of the fluid control device and/or force being exerted thereon by an external device/system exert a force greater than the upward forces exerted on the fluid control device by the fluids flowing from the open well head casing. These upward forces exerted by the fluid from the well head casing (pipe) tend to push the fluid control device upward and out of the well bore, and these forces continue until the final closure point where the solid tool diameter is the same or greater than the inside diameter of the well head casing. At this point, the tapered section has an interference fit, which creates the final fit/seal with the well head casing.
In a preferred embodiment, a soft material (sealing material) such as lead, rubber, a softer metal such as aluminum, etc., is coated, affixed or disposed adjacent on/to the outer circumference of at least a portion of the fluid control device, so as to be operable to form a interference or compression fit (seal) between the fluid control device and the well head casing and/or outflowing piping.
In another preferred embodiment, sections or portions of sections of the fluid control device, including but not limited to the adjacent tapered section and sections above same, are coated with a soft (sealing) material as described above such that as the fluid control device is lowered to specific depths in the well bore pipe, cracks in the well bore pipe below the sea surface can be surpassed by smaller diameter sections of the fluid control device until the section or portion of section coated with the soft material having an outer diameter equal to the inside diameter of the well bore pipe below the cracks seats/seals against the well bore pipe below the cracks. This enables sealing of the well bore pipe below the cracks, thereby preventing leakage/outflow of oil, gases, fluids, etc. into the substrate surrounding the well bore. In particular, this preferred embodiment provides the ability to seal cracked piping even thousands of feet below the subsurface.
In another preferred embodiment, a shoulder is formed on the tool which is larger in diameter than the well head casing. As the tool is lowered into the well head, the shoulder of the tool comes in contact with and rests on the top of the well head casing. Preferably, the soft material (sealing material) described above is disposed on and/or adjacent to the shoulder, so as to assist in providing a tight seal between the shoulder and well head casing.
In a further preferred embodiment, threads are formed on/adjacent to the larger end of the fluid control device so as to engage threads formed on the well head casing. The threaded engagement between the fluid control device and well head casing assists in forming a fluid tight seal between the well head casing and/or outflowing piping and the fluid control device.
In another preferred embodiment, the fluid control device comprises a plurality of sections having different cross-sections, where one end of the fluid control device has the smallest circular cross section which is to be inserted first in the well head. This first section of smallest diameter, having a tip, connects with a tapered round section at an end opposite the tip, the tapered round section increasing in diameter until the diameter of the tool is larger than the inside diameter of the well casing. These separate sections of the fluid control device can be formed integral with one another, or can be formed separately and then connected by threaded engagement, welding, or the like.
In accordance with the above, in a first preferred embodiment there is provided an apparatus for controlling and/or stopping the flow of petroleum and/or natural gas from an open well head on the sea floor in which the well head is in communication with a subterranean formation, said apparatus comprising:
a flow control device comprising:
(a) an elongated member which can be lowered at least partially into an open well head and which is comprised of a plurality of sections of different diameters, including a lowermost end section having a constant diameter less than about half of the inside diameter of the well head casing, and
(b) a tapered section in connection or formed integral with the elongated member, the tapered section having a variable diameter which increases to a diameter at least equal to the inside diameter of the well head casing, and
(c) an end section in connection or formed integral with the tapered section, the end section having a diameter greater than or equal to the outside diameter of the well casing,
wherein the overall mass of the fluid control device exerts a force sufficiently great so as to overcome any upward force created by flowing fluids, such as petroleum and/or natural gas, and wherein which mass results in the downward movement of the fluid control device into the well head casing resulting in closure of the well head.
In a second preferred embodiment used in connection with the first preferred embodiment is an apparatus wherein the fluid control device is comprised of a plurality of sections which can be connected together.
In a third preferred embodiment there is provided in connection with the second preferred embodiment above, an apparatus wherein one or more of the plurality of sections are in threaded engagement with one or more adjacent sections.
In the fourth preferred embodiment there is provided in connection with the third preferred embodiment, wherein the apparatus further comprises a guide means operable to align the fluid control device with/into the open well head.
In the fifth preferred embodiment there is used in connection with the first through fourth preferred embodiments above, wherein the apparatus/fluid control device is lowered into the well head casing from a drilling ship.
In the sixth preferred embodiment there is provided in connection with the first through fifth preferred embodiments above the apparatus wherein the drill ship uses drilling pipe (in communication with the apparatus/fluid control device) to lower the fluid control device to the sea floor and into the open well head.
In the seventh preferred embodiment a method is provided for controlling uncontrolled flow of petroleum and/or natural gas from an open well head projecting from the sea floor, the method comprising:
(a) positioning a fluid control device above an alignment means, which in turn is positioned above an open well casing on the sea floor, (b) lowering the fluid control device through the alignment means and into the open well casing, and (c) lowering the fluid control device into the open casing until the fluid control device seals the well casing, thereby halting the flow of petroleum and/or natural gas therefrom.
In an eighth preferred embodiment there is provided in connection with the seventh preferred embodiment a method wherein a drilling ship is used to lower the fluid control device into the open well head casing.
In a ninth preferred embodiment there is provided in connection with the seventh preferred embodiment a method wherein the fluid control device is lowered into the well head casing by means of drilling pipe in communication with the fluid control device to the sea floor.
Additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The aspects of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention. The embodiments illustrated herein are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown, wherein:
FIG. 1 is a side view of a drilling ship fitted with a drilling rig positioned above an open well head on the bottom of the sea, illustrating in particular the fluid control device of the present invention for controlling the flow of fluids from the open well head extending from the sea floor.
FIG. 2 is a side view of the drilling ship shown in FIG. 1 , in which the fluid control device of the present invention is being lowered into the open well head.
FIG. 3 is a side view of the drilling ship shown in FIG. 1 , in which the fluid control device of the present invention has been deployed by being lowered into the open well head to plug same and halt the flow of fluids from the well head casing.
FIG. 4 is a side view of the fluid control device of the present invention, illustrating various sections thereof as the device is lowered into the well head casing.
FIG. 5 is a side view of the fluid control device shown in FIG. 4 , illustrating a tapered section thereof when it is about to enter the well head casing.
FIG. 6 is a side view of the fluid control device shown in FIGS. 4 and 5 , illustrating a tapered section of the apparatus in the well head casing.
FIG. 7 is a side view of the fluid control device of the present invention, illustrating the disposition of the fluid control device when a shoulder therein is resting on the top of the well head casing, thereby disposing the apparatus in sealing engagement with the well head.
FIG. 8( a ) is a cross-sectional view of the fluid control device of the present invention and well head casing, illustrating the alignment and disposition of the device right before the device is lowered into the well head casing.
FIG. 8( b ) is a partial enlarged cross-sectional view of the fluid control device of the present invention and well head casing, as shown in section “A” of FIG. 8( a ), illustrating the alignment and disposition of the device right before the device is lowered into the well head casing. In this case, the diameter ratio of the outflowing pipe and the fluid control device allows for the fluid control device to be easily positioned, aligned and placed into the outflowing pipe with least resistance.
FIG. 9( a ) is a cross-sectional view of the of the fluid control device of the present invention and well head casing, illustrating the alignment and disposition of the device right after the smallest diameter section thereof has been lowered into the well head casing. This gradual diameter increase in the fluid control device also increases the outflowing pipe as the segments of the fluid control device enter the outflowing piping. This gradual pressure build up not only reduces the fluid flow but also stops damage to the outflowing pipes from shock or sudden pressure buildup that can exceed the material properties of the outflowing piping.
FIG. 9( b ) is a partial enlarged cross-sectional view of the fluid control device of the present invention and well head casing, as shown in section “A” of FIG. 9( a ), illustrating the alignment and disposition of the device right after the smallest diameter section thereof has been lowered into the well head casing.
FIG. 10( a ) is a cross-sectional view of the of the fluid control device of the present invention and well head casing, illustrating the alignment and disposition of the device right as the tapered section thereof is being lowered into the well head casing.
FIG. 10( b ) partial enlarged cross-sectional view of the fluid control device of the present invention and well head casing, as illustrated in section “A” of FIG. 10( b ), illustrating the alignment and disposition of the device right as the tapered section thereof is being lowered into the well head casing as shown in area “A” of FIG. 10( a ).
FIG. 11( a ) is a cross-sectional view of the of the fluid control device of the present invention and well head casing, illustrating the alignment and disposition of the device after the shoulder thereof has come to rest upon the well head casing, thereby sealing same. However, sealing is not necessarily at the top portion of the outflowing pipe. Rather, sealing can be achieved anywhere in the outflowing piping because the segments can be lined with soft materials so that they can be pressed or positioned into cracked pipes and provide the sealing at a solid (uncracked) portion. The soft lining can be hundreds to thousands of feet in length if needed.
FIG. 11( b ) is a partial enlarged cross-sectional view of the fluid control device of the present invention and well head casing, as illustrated in section “A” of FIG. 11( a ).
FIG. 11( c ) is a partial enlarged cross-sectional view of the fluid control device of the present invention and well head casing, as illustrated in section “B” of FIG. 11( a ).
FIG. 12 is a partial cross-sectional view of the fluid control device, illustrated the preferred embodiment wherein the fluid control device is configured to seal the well bore pipe below a subsurface crack therein.
DETAILED DESCRIPTION OF THE INVENTION
As illustrated in FIGS. 4 and 8( a ), the fluid control device 10 of the present invention is generally comprised of three members, i.e., elongated member 31 , tapered portion 28 (which may be coated with a soft material such that the diameter of the tapered portion is greater than the inside diameter of the outflowing pipe) and top portion 25 . In particular, the elongated member 31 having a tip 33 at one end thereof, is smallest in diameter, and is disposed at one end of the device 10 so as to be the first element of the device 10 to be inserted into a well head casing 5 . The elongated member 31 is in communication with, or formed integral with, a tapered portion 28 at juncture 35 , the juncture 35 being at an end opposite the tip 31 . The elongated member 28 is in communication with or formed integral with top portion 25 . Top portion 25 preferably has a shoulder 26 formed therein, the shoulder 26 having a diameter equal or greater that the outside diameter of the well head casing 5 .
In a preferred embodiment, as mentioned above and as illustrated in FIG. 12 , in order to seal a subsurface crack 59 in the well bore pipe 61 , the fluid control device 10 is configured such that a tapered portion 28 increases in diameter greater than the inside diameter of the pipe 61 below the crack 59 , and is coated with a soft material 63 in a portion adjacent the crack 59 so as to seal the pipe in the area adjacent the crack 59 . The pipe 61 may alternatively be sealed well below the crack 59 , by tailoring the diameter of the fluid control device accordingly. In either event, by sealing the pipe 61 below the crack 59 , leakage of outflowing fluids into the surrounding substrate via the crack 59 may be prevented.
Preferably, each segment (section) of the fluid control device 10 is tapered, even if ever so slightly, such that that there are no impacts between the device 10 and the well bore casing 5 or pipe 61 that can damage the casing or pipe. There is no limitation on the degree of taper; the taper can be hundreds of feet long and can have a over lay of one hundred feet or more of soft material greater than the inside diameter of the outflowing piping so that a seal can be formed between the fluid control device and the well bore pipe hundreds or even thousands of feet below the surface. The soft material is press fit, so as to create an interference/compression fit, until the fluid flow from a solid or cracked outflowing pipe is halted.
The fluid control device of the present invention shown in FIG. 4 , including equipment for using same, is depicted generally in FIG. 1 , in which a drilling ship 1 is positioned over an open well casing 5 projecting from the sea floor 3 . Drilling ship 1 comprises a derrick 7 used for lowering the fluid control device 10 of the present invention to the sea floor 3 and into open well head 5 .
Surrounding well head 5 is a platform 6 which rests on the sea floor 3 . Platform 6 provides a stable, level base upon which to mount a support means 17 along which can be mounted alignment means 20 including a funnel shaped guide means. Optionally, fluid control device 10 can be guided to a position directly over well head 5 by means of alignment means 20 resting on support means 17 . The drilling ship 1 can be stabilized with a geographic positioning system (GPS) in communication with on board stabilizers, or any other suitable conventional device to maintain the drilling ship 1 in a fixed position during the process of installing fluid control device into open well head 5 .
FIGS. 1-3 illustrate one preferred method of lowering fluid control device 10 from the drilling ship 1 using conventional drilling pipe 13 , which may be connected one to the other by means of threads (not shown), friction welds, or other conventional means of attachment. Preferably, the end of drilling pipe 13 can be secured to the fluid control device 10 by means of threads or any other conventional locking means used in the drilling industry. In an alternative preferred embodiment, steel (or other high tensile strength) cable (not shown) can be used to lower fluid control means 10 from drilling ship 1 into open well head 5 . Any conventional locking means can be used to secure fluid control means 10 to the steel cable.
In operation, a drilling ship 1 lowers fluid control device 10 via conduit 13 from a position adjacent to well head 5 as shown in FIGS. 1 and 4 , to a lower position as shown in FIGS. 2 and 5 (wherein a tapered portion 28 is shown projecting above well head 5 ). Upon further lowering, the fluid control device 10 is inserted farther into the well head 5 , as shown in FIGS. 3 and 6 (wherein only a top portion 25 of fluid control means 10 is shown projecting above well head 5 ). Finally, the top portion 25 engages with the well head, thereby sealing same, as illustrated in FIG. 7 .
Specifically, FIGS. 4 , 8 ( a ) and 8 ( b ) illustrate preferred sections of the fluid control device 10 including a lowermost section which extends from the tip 33 to a juncture 35 with a tapered section 28 . The progressive lowering of fluid control device 10 is illustrated in FIGS. 5-7 and 9 ( a )- 11 ( c ), during which fluid control device 10 is lowered from above open well head 5 (see FIGS. 4 , 8 ( a ) and 8 ( b )) into well head 5 , and then tapered section 28 enters well head 5 (see FIGS. 6 , 10 ( a ), 10 ( b )), and finally section 25 of fluid control means 10 comes into contact with and in sealing engagement with well head 5 (see FIGS. 7 , and 11 ( a )-( c )).
FIGS. 1-3 show the optional use of a support means 17 resting on a platform 6 , and the use of alignment means 20 to assist in guiding fluid control means 10 into the well head 5 . Although not required to insert the fluid control device into the well head, the alignment means 20 decreases the difficulty of aligning the tip 33 with the well head casing 5 .
The fluid control device 10 of the present invention can be gradually inserted into the orifice or open end of a flowing well head 5 so that the flow is gradually reduced with each segment of the tool tip ( FIGS. 4-7 ). In the case of a deep drilled oil pipe, the segment lengths could be hundreds of feet or longer, as the flow and pressures require. Importantly, a gradual reduction in pressure is preferable, so as not to shock the current flowing pipe (well pipe) because this could further rupture the existent pipe assets.
The fluid control device 10 can be made such that it could be transported or delivered to the targeted well head casing using current (conventional) oil pipe segments. However, rather than inserting piping onto/into the well head casing 5 , the fluid control device, as shown in FIGS. 1-3 , would be attached to the leading oil pipe segment. The current oil pipe sections would serve to deliver, locate, position and apply pressure onto the solid tip 33 of the fluid control device 10 , so as to overcome the forces (flows and pressures) of the flowing oil and gas mixture. Conventional drilling rigs can apply 600,000 pounds or more of pressure upon the pipe segments 13 , and thus upon the fluid control device 10 , an amount of pressure capable of overcoming tremendous flow rates of petroleum, byproducts thereof, and natural gases.
An alternate method of using the solid fluid control means 10 is to configure the device 10 to have a mass greater than the forces being exerted by the flowing oil and gas mixture, and thereby allowing gravity to provide most or all of the force necessary to plug the well. This mass could be derived (consist of) only mass from the solid fluid control means 10 itself, or by adding a shoulder and/or connection means for the addition of extra weights (not shown). The combination of the solid fluid control means 10 with the drill piping 13 can be used to locate and lower the fluid control means 10 into the well head 5 and then weights can be added so that the connection pipes can be sealed and cut-off.
Further, as mentioned above, the fluid control means 10 can have a sealing means (i.e., a soft material, O-ring, etc.) coated or disposed thereon operable to create a seal between the device 10 and the well head 5 . Alternatively, as shown in FIG. 12 , a seal between the device 10 and the ID of a subsurface portion of the outflowing pipe using soft materials coated/disposed on the fluid control device sections (such as an “O” ring, soft metal, etc.), by simply pressing the soft portion of a section beyond the cracked section of a pipe against the pipe, so as to provide the sealing means. This could be any conventional sealing device including a tapered section that contacts the well head casing. The forces or shear weight add the necessary load to stop or reduce the flow at the joint.
In a preferred embodiment, as mentioned above, a soft material contact can be disposed on at least a portion of the tapered section 28 , shoulder 26 and/or top section 25 to provide a greater sealing effect, the soft material consisting of one or more of lead, rubber or plastic to seal the joint. Further, an expansion joint, such as a collet, can be used to expand and create a seal between the pipes.
The fluid control means 10 of the present invention provides a drill team with an ability to slow the flow rate of the oil and gas mixture using a segmented fluid control means 10 . It also reduces the expansion of the methane gas to a rate that freezing does not occur as is in the current BP outflow. Further, it gives drillers the ability to go beyond any cracked pipe segment with a smaller diameter segment, and thus reduce the outflow and/or natural gas. Flow reduction (not stoppage) is also a desired feature.
This means that cracked pipes hundreds if not thousands of feet below the sea surface can be bypassed or repaired using the device and method of the present invention. With the use of soft material lining on the taper fluid control device sections, a seal between the ID of the outflowing pipe and the fluid control device can be made. There is no other current method or device that can achieve same. A sealing means can also be used to seal a well head at any location desired.
Although specific embodiments of the present invention have been disclosed herein, those having ordinary skill in the art will understand that changes can be made to the specific embodiments without departing from the spirit and scope of the invention. Thus, the scope of the invention is not to be restricted to the specific embodiments. Furthermore, it is intended that the appended claims cover any and all such applications, modifications, and embodiments within the scope of the present invention
|
A fluid control device is provided for controlling and/or halting an uncontrolled flow of petroleum or natural gas from an open well head on the sea floor. The fluid control device includes an elongated member having a diameter smaller than the inside diameter of the well head casing. A tapered section in connection with the elongated section, has a diameter equal to or greater than the inside diameter of the well head casing. An end section connected to the tapered section has a diameter greater than or equal to the outside diameter of the well head casing. The fluid control device, under its own mass or under an external force, overcomes the upward forces created by the flowing petroleum or natural gas, resulting in sufficient downward movement of the fluid control device and contact with the open well to seal the well head casing or drill pipe.
| 4
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to window coverings, and more particularly, to fabric covered and fabric accented assemblies for enclosing and ornamenting the headrail of a window covering, for decorating interior window tops, or for accomplishing both of these objectives.
2. Description of the Prior Art
Several types of hanging window covering units have been proposed, and generally, these window covering units hang from a headrail constructed from metal or plastic. As these headrails are designed for structural adequacy, they are not usually aesthetically pleasing. Therefore, to provide an aesthetically pleasing appearance, it has become common practice to use a window top decorating assembly commonly known as a "cornice" or "valence" to conceal the headrail, and often times, to decorate the entire top of the window. Furthermore, in many cases, the aesthetic appeal of these decorating assemblies is improved by covering or accenting them with fabric or other thin material.
For example, U.S. Pat. No. 4,644,991 to Boyd discloses a cornice assembly having a spring loaded, interchangeable tapestry cover for improving the aesthetic appeal of the frontal surfaces. U.S. Pat. No. 4,664,421 to Basmadji et al, U.S. Pat. No. 4,828,002 to Ashby, and U.S. Pat. No. 5,042,548 to Attal each disclose a cornice-type assembly consisting of a series of panels in which strips of colored fabric, plastic, or metal can be inserted to provide improved aesthetic appeal. Specifically, Basmadji and Attal disclose assemblies consisting of front and side panels having grooves along their upper and lower edges which accept and retain strips of thin material such as wall paper or fabric. Ashby teaches an assembly similar to that of Basmadji and Attal except that the side panels taught by Ashby are not equipped for accepting or retaining any type of decorating strips. U.S. Pat. No. 5,042,549 to Roberts discloses a fabric covered cornice-type assembly constructed from rigid plastic foam.
Although the decorating assemblies of each of these patents address the problem of concealing the headrail of a window covering unit or decorating the top of a window, each are subject to one or more of the following deficiencies: 1.) The physical structure limits the level of aesthetic value provided, 2.) The structure does not readily lend itself to being covered with a fabric: or other thin material, 3.) The structure does not readily lend itself to providing unique shapes and diverse sizes.
Specifically, the decorating assembly taught by Boyd does not have a structure that would allow it to be covered with fabric. As taught, this assembly is only suited to have its front surfaces covered with fabric. As a result, the edges and therefore portions of the backside, would be exposed. Furthermore, its physical structure significantly limits the shape of the portion of the assembly to be covered to rectangular. The decorating assemblies taught by Basmadji, Ashby, and Attal each have physical limitations that make them unsuitable for covering with a fabric. The first of these limitations is the front surfaces not being flat. This condition would cause unacceptable discontinuities in a fabric covering. Secondly, as taught, the structures of the assemblies do not readily lend themselves to providing any shape other than rectangular. Furthermore, the depth (i.e. overall thickness) of the front and side panels is far too thin to be considered a suitable or desired structure for covering with a fabric.
SUMMARY OF THE INVENTION
The present invention is directed to provide a window top decorating assembly that overcomes or substantially reduces the noted deficiencies of the prior art by providing a structure which readily lends itself to: 1.) being covered with a fabric material or the like and 2.) being constructed in a variety of sizes and shapes.
According to a preferred embodiment of the invention, a window top decorating assembly for covering with a fabric material or the like is provided. The decorating assembly generally includes a structural assembly having two side panels and two linear members having preferably flat front walls and at least one offset rear wall. The offset rear walls establish a channel running in the longitudinal direction that provides the linear members and the side panels with the desired overall depth and provides a location where the fabric covering can be affixed. In the most simplistic case, the structural configuration of the linear members is represented by a rectangular tube or a U-shape channel. Preferably, the overall depth of the side panels and the linear members is the same. This depth is typically one-quarter of an inch or greater. Furthermore, it is also preferable that the rear walls of the linear members and the side panels be configured such that when the fabric is affixed, the portions of the backside of the assembly which can be viewed from the front are concealed by the fabric. In the preferred case, the linear members and side panels are joined to each other by mounting posts integral to the side panels that engage into the linear members. These mounting posts are generally located at the top and bottom of the side panels such that one linear members is flush with the top surface of the side panel and the other linear member is flush with the bottom surface of the side panel. As described, such a structural configuration produces an assembly without a top surface. Optionally, a mounting post can be located at the top rear position of the side panels and a third linear member can be employed to provide an assembly with a front, sides, and top. Also, the side panels can optionally be equipped with cavities for receiving unions rather than being equipped with mounting posts, and the linear members can be joined with the side panel using discrete unions. In all embodiments, it is preferable that the front surfaces of the linear members and the side panels be smooth.
The fabric covering is preferably affixed to the assembly using either an adhesive method or a mechanical fastening system. The adhesive method generally consists of using glue to affix the fabric to the rear surface of the linear members and side panels. In one configuration, the mechanical fastening system generally consists of a series of slots or ribs on the rear of the linear members and the side panels and a set of fabric fastening strips. The fabric is retained by positioning it over the slot or rib and then engaging a fastening strip along the length of the slot or rib. Optionally, the fabric fastening strip can be replaced by discrete fabric fastening clips. Unlike the adhesive method, the mechanical fastening system has the advantage of enabling the fabric to be readily released once attached.
Preferred embodiment of the invention, only one of the two linear members in the frontal positions of the first embodiment has a rear wall. The linear member without the rear wall generally does not provide a preferred location for affixing the fabric, and is generally positioned in the lower mounting position. Preferably, this linear member has a cross-section enabling it to be affixed to the side panels via the same method used for mounting the other linear members.
In a first alternate configuration of the above mentioned embodiments, a stepped or arched contour is added to the upper or lower portion of the front surface of the assembly by use of contoured unions used in combination with linear members or by use of a contoured traverse member. Generally, a decoration assembly can have contours including single and multiple arches or single and multiple steps. In the case of the stepped contours, the corners of the steps are generally either rounded or square.
In a second alternate configuration of the above mentioned embodiments, at least one of the side panels is replaced with an end cap. The end cap enables an assembly to be constructed without the fabric covering on one or both ends. This configuration is desired in applications where the assembly is being installed with one or both ends against a wall or other similar structure.
Furthermore, in all of the above embodiments and alternate configurations, the ensuing structure results in an assembly having a front surface with an opening. Optionally, the linear members and side panels can be configured to establish a recess in the front surfaces to receive an insert panel such that the opening is eliminated. Where batting or foam is used under the fabric covering, this insert panel provides a uniform underlying surface.
Still furthermore, in all of the above embodiments and alternate configurations, the linear members can be configured to accept a support member which spans between the linear members to provide structural stability. These support members are especially desirable in applications where the length of the linear members induces bowing.
According to a third embodiment of the invention, the two linear members of the assembly of the first embodiment are replaced by a panel member. The panel member is of sufficient height such that its upper longitudinal edge is flush with the top surface of the side panel and its lower longitudinal edge is flush with the bottom surface of the side panel. The relevant alternate configurations mentioned above also apply to this embodiment.
A fourth embodiment of the invention entails use of a panel member to establish the front of the structural assembly and linear members to establish the sides of the structural assembly. In a fifth embodiment, linear members are used in combination with a set of unions to form both the front and sides of the structural assembly.
Mounting of the decorating assembly is generally accomplished using preferably two or more wall mount or headrail mounting brackets. In the case of wall mount brackets, the brackets are fastened to the wall using mechanical fasteners such as screws, and the decorating assembly attaches to the brackets. In the preferred case, the brackets are attached to the side panels. Optionally, the brackets can be attached to the upper front linear member or to the upper rear linear member, if one is present. In the case of headrail mounting brackets, the brackets preferably clip onto the headrail and the decorating assembly attaches to the brackets. To ensure mounting under diverse conditions, the bracket can be configured to accommodate a variety of headrail designs and headrail-to-assembly distances.
Other objects and advantages of the invention will become apparent to those skilled in the art from the detailed description of the invention below and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective, fragmentary view of the assembled, fabric covered decorating assembly of this invention mounted to the headrail of a window covering unit with the fabric being partially cut away to show the underlying structure.
FIG. 2 is a perspective view similar to FIG. 1 showing the major structural elements of the structural assembly in exploded relation to the window covering unit.
FIG. 3 is a perspective, fragmentary view showing a closed cross section-type linear member configuration.
FIG. 4 is a perspective, fragmentary view showing an open cross section-type linear member configuration.
FIGS. 5A and 5B are perspective, fragmentary views showing linear members with a support member and an insert panel, respectively.
FIG. 6 is a perspective, fragmentary view showing a structural assembly including an upper rear linear member.
FIG. 7 is a perspective view showing the configuration of the side panel of FIGS. 1 and 2.
FIG. 8 is a sectional view of the portion indicated by line 8--8 in FIG. 7.
FIGS. 9A thru 9F are perspective views showing a variety of mounting bracket configurations.
FIG. 10 is a perspective view showing a side panel intended for use with upper and lower front linear members and an upper rear linear member.
FIGS. 11A and 11B are perspective views of discrete unions.
FIG. 12 is a perspective, fragmentary view showing the assembled relation of a mounting bracket intended for structural assemblies with a linear member in the upper rear position.
FIGS. 13A, 13B, and 13C are perspective, fragmentary views showing mechanical fabric fastening elements.
FIG. 14 is a perspective view of a side panel similar to that of FIG. 7 except having cavities instead of mounting posts and having grooves for fabric fastening.
FIGS. 15A thru 15D are front elevation views showing a variety of frontal profiles for the decorating assembly of this invention.
FIGS. 16A thru 16G are front elevation views showing a variety of structural elements for providing the frontal profiles of the decorating assemblies in FIGS. 15A thru 15D.
REFERENCE NUMERALS IN DRAWINGS
1 Decorating Assembly
2 Window Covering Unit
3 Fabric
4 Headrail
5 Foam Material
6 Structural Assembly
8 Front Wall
15 Lip
20 Side Panel
21 Front Edge
22 Front Wall
23 Rear Wall
24 Mounting Post
25 Front Surface
26 Receptacle
27 Rear Surface
28 Slot
29 Top Edge
30 Bottom Edge
40 Mounting Bracket
41 Clip Portion
42 Upper Ridge
43 Lower Ridge
44 Extension Arm
46 Shoulder
48 Shaft
50 Linear Member
51 Panel Member
52 Front Wall
54 Transverse Wall
55 Flange
56 Rear Wall
57 Front Surface
58 Rear Surface
60 Slot
61 Channel
62 Longitudinal Projection
64 Recessed Portion
66 Support Member Slot
68 Fabric Fastening Flange
70 Groove
72 Retaining Strip
73 Legs
81 Support Member
82 Notch
83 Insert Panel
88 Cavity
89 Union
90 Side Panel Engaging Portion
91 Vertical Wing
92 Horizontal Wing
93 Linear Member Engaging Portion
94 End Cap
95 Flange
96 Hole
97 Retaining Arm
98 Right Angle Coupling
99 Nipples
100 Right Angle Union
101 Frontal Edge
102 Linear Coupling
106 Double Step Union
108 Single Step Union
110 S-Curve Union
112 Contoured Structural Member
DESCRIPTION OF THE PREFERRED EMBODIMENTS
For the preferred embodiments of the invention shown in the accompanying figures and described herein, it will be understood that the present invention relates specifically to the physical configuration of the invention and generally to the configuration of the related window covering unit.
Referring to FIG. 1, decorating assembly I is shown in relation to a typical window covering unit 2. In this particular embodiment, decorating assembly 1 is mounted to headrail 4 of window covering unit 2 by mounting bracket 40. In most instances, structural assembly 6 will be covered by fabric 3. Optionally, foam material 5 may be used to provide a cushioned appearance. In most cases, fabric 3 and optional foam material 5 are affixed to side panels 20 and linear members 50 using a staples or hot melt adhesive.
As can best be seen in FIG. 2, the embodiment of decorating assembly 1 shown in FIG. 1 generally includes a structural assembly 6 having at least two linear members 50 and at least one side panel 20. Linear members 50 are generally injection molded or extruded from a plastic material such as polyvinylchloride (PVC), polypropylene, or ABS. Side panel 20 is generally injection molded from the same group of materials as linear members 50. Typically, side panel 20 will include at least two mounting post 24 extending rearwardly from front wall 22. In most cases, at least one of linear members 50 will have a cross section including front wall 52 establishing front surface 57, rear wall 56 establishing rear surface 58, and at least one transverse wall 54 establishing channel 61 between front wall 52 and rear wall 56. Flanges 55 extend from front wall 52 and from transverse wall 54 establishing slots 60. Optionally, flanges 55 can be configured to extend from rear wall 56 to provide the required functionality. Slots 60 are configured to accept mounting posts 24 such that linear members 50 can be attached to side panels 20 with front surface 57 flush with front edge 21 and with traverse wall 54 flush with adjacent top edge 29 or bottom edge 30.
FIG. 3 shows linear member 50' having a closed cross section configuration and FIG. 4 shows linear member 50 having an open cross section configuration. When used in common assembly, the distance between the front surface 57 and rear surface 58 of linear member 50 in FIG. 3A is generally the same as the distance between front surface 57 and longitudinal edge 53 of linear member 20 in FIG. 3B. In cases where linear members 50 are extruded, the open cross section configuration will generally provide superior results. Linear member 50 and 50' may further include longitudinal projections 62 which establish recess 64 and in the case of linear member 50' support member slot 66. As shown in FIG. 5A, support member 81 is located within support member slot 66 to provide support between linear members 50. Support member 81 is generally injection molded or extruded from a plastic material. The longitudinal length of support member 81 is generally three to four times the width of support member slot 66. And to accommodate a variety of assembly sizes, support member 81 includes a plurality of notches 82 enabling it to be sized to the appropriate height by breaking at the correct notch 82. For applications where it is essential to have a structural assembly 6 with a front surface without an opening, insert panel 83 can be located in recessed portion 64, as shown in FIG. 5B. Insert panel 83 can be injection molded from a rigid plastic material or constructed from a readily available material such as foam core-type poster board.
As shown in FIGS. 7 and 8, mounting of decorating assembly 1 is facilitated by receptacle 26 having slot 28 located on the rear side of side panel 20. As best seen in FIG. 8, shaft 48 of mounting bracket 40 engages in slot 28 with shoulder 46 securely locating shaft 48 within slot 28. In the embodiment shown, clip portion 41 of mounting bracket 40, being located at the opposite end of extension arm 44 from shaft 48, is configured to attach to headrail 4 of window covering unit 2 in FIGS. 1 and 2. Ridge 42 of clip portion 41 engages under lip 15 of front wall 8 of headrail 4 and ridge 43 firmly engages against the rear surface of front wall 8. Furthermore, receptacle 26 can be replaced by a multitude of structural configurations enabling decorating assembly 1 to be mounted to a wall or to the headrail of a window covering unit. And still furthermore, clip portion 41 could be configured to accept a variety of headrail configurations not shown.
FIGS. 9A thru 9D show a variety of alternate configurations for mounting bracket 40 as configured for use with receptacle 26 shown in FIGS. 7 and 8. Specifically, 9A and 9C show mounting bracket 40 with flange 95 instead of clip portion 41. Flange 95 with holes 96 for fasteners such as screws is employed in cases where it is desirable to mount decorating assembly 1 to a wall rather than to headrail 4 of window covering unit 2. FIGS. 9C and 9D show mounting bracket 40 with extension arm 44 having a downward bend for applications where it is desired to have decorating assembly 1 downwardly offset from window covering unit 2. Similarly, extension arm 44 could have an upward bend enabling decorating assembly 1 to be upwardly offset.
FIG. 10 shows side panel 20' of FIGS. 1 and 2 with cavities 88 rather than mounting posts 24 and configured with a third cavity 88 to provide for a linear member 50 in the upper rear position of side panel 20 to provide a top surface on decorating assembly 1. Cavity 88 located at the top rear corner of side panel 20' enables a linear member 50 to be installed with front surface 57 flush with top edge 29 such that decorating assembly 1 can be constructed with a top surface. Decorative assembly 1 having linear member 50 at the upper rear position of side panel 20' can be mounted as previously discussed, or it can be mounted using mounting bracket 40 of FIG. 9E or 9F. Mounting bracket 40 in FIG. 9E is configured to be used with structural assembly 6 having a linear member 50 in the upper rear position. Mounting bracket 40 can be configured to attach to a wall via flange 95 or to headrail 4 of window covering unit 2 via clip portion 41. The upper rear linear member 50 rests on top of extension arm 44. As shown in FIG. 12, retaining arm 97 engages behind upper rear linear member to hold decorating 1 in place. Similarly, mounting bracket 40 of FIG. 9F can be used to mount decorating assembly 1 to headrail 4 of window covering unit 2.
This configuration is best achieved by extrusion while the configurations of side panel 20 in FIGS. 7 and 10A is best achieved by injection molding. The major difference between these configurations is that side panel 20 of FIG. 10B has the ability to provide a more extensive rear wall 56.
Union 89 of FIG. 11A is used with linear members 50 having flanges 55 that establish slot 60. Union 89' of FIG. 11B is used with linear members 50 not having flanges 55. In either case, horizontal and vertical wings 91 and 92 of side panel engaging portion 90 securely fit within cavities 88. In the case of linear members 50 having slot 60, mounting post 24 of linear member engaging portion 93 fits into slot 60. In the case of closed cross section type linear members 50' not having slot 60, horizontal and vertical wings 91 and 92 of linear member engaging portion 93 fits within channel 61.
FIGS. 13A, 13B, 13C, and 14 show a mechanical fastening system for retaining fabric 3. The major parts of this system include fabric fastening flange 68, grooves 70, and retaining strip 72. Fabric fastening flange 68 is preferably in combination with rear wall 56 of linear member 50 or 50 with at least one groove 70 running longitudinally along the length of fabric fastening flange 68. Fabric 3 is fastened by positioning it over groove 70 and engaging legs 73 of retaining strip 72 into groove 70 such that fabric 3 is bound in groove 70. Retaining strip 72 is preferably constructed of a resilient plastic material such that legs 73 are forcibly retained within groove 70. Similarly, fabric 3 is fastened to side panels 20 using similar structural elements As shown in FIG. 14, rear walls 23 include grooves 70. Optionally, fabric fastening flange 68 could be omitted and grooves 70 could be integral with rear wall 56 of linear members 50 or 50.
FIGS. 15A through 15D show a variety of decorating assemblies 1 having a contoured geometry along frontal edge 101 . FIG. 15A shows a single step square corner geometry. This geometry is provided using a right angle coupling 98 of FIG. 16A. Similarly, this geometry is also provided by right angle union 100 and linear coupling 102 of FIGS. 16 B and 16C., respectively. Right angle coupling 98 includes nipples 99 for attachment directly to linear members 50 or 50. The cross section of nipples 99 is determined by the specific geometry of slot 60 or channel 61. In the case where right angle union 100 is used, linear coupling 102 joins right angle union 100 to linear members 50 or 50. The single step square corner geometry is also provided by single step union 108 shown in FIG. 16E. Similarly, the single step rounded corner geometry of decorating assembly 1 shown in FIG. 15B is provided by S-curve union 110 in FIG. 16F, and the double step square corner geometry of decorating assembly 1 shown in FIG. 15C is provided by double step member 106 in FIG. 16D. The arched geometry of decorating assembly 1 of FIG. 15D is provided by contoured structural member 112 in FIG. 16G. Similarly, a multitude of geometric contours could be provided by one piece members similar to contoured structural member 112 shown in FIG. 16G.
Although the description above contains many specifics, these should not be construed as limiting the scope of the invention, but as merely providing illustrations of some of the preferred and potential embodiments of the invention at the time this application was drafted. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents along with the examples and descriptions given, rather than by the examples and descriptions alone.
|
An assembly for decorating the top of a window. Generally, the assembly includes a pair of linear members with side panels attached at each end. The side panels have integral mounting posts being received by slots in the linear members. Optionally, the linear members are attached to the side panels with discrete couplings that are received by both the side panels and the linear members. A fabric covering is applied over the assembly and attached to the rear of the assembly by use of glue. Optionally, the fabric covering is attached via a mechanical fastening system located on the rear of the assembly. Mounting brackets are used to secure the window top decorating assembly directly to the wall surrounding the window or, if a window covering unit is in place, to the headrail of the window covering unit.
| 4
|
This application claims domestic priority based upon U.S., provisional Patent Application Ser. No. 60/047,872 filed May 29, 1997.
The present invention relates generally to a self-adjusting fifth wheel hitch assembly for use on pickup trucks and similar vehicles used to tow fifth wheel trailers. The hitch assembly having the features of the present invention allows fifth wheel trailers to be towed using short bed pickup trucks and other trucks having a relatively short distance between the rear portion of the passenger compartment and the rear axle.
BACKGROUND OF THE INVENTION
Fifth wheel trailers and tow vehicles for fifth wheel trailers are generally well known in the art. Fifth wheel trailers are much longer, roomier, and heavier than typical tent campers and travel trailers, and thus a fifth wheel trailer typically requires a specially modified, relatively heavy tow vehicle such as a heavy duty pickup truck. The front portion of a fifth wheel trailer extends over the rear portion of the tow vehicle so that a portion of the trailer's weight is carried directly over the rear axle of the tow vehicle. In order to accommodate the weight of the trailer a special hitch assembly is required.
The front portion of the trailer includes a pin box which includes a support plate and a downwardly extending hitch pin. A base plate having an aperture and a latch mechanism is mounted to the tow vehicle, and the support plate carried by the pin box rests on the base plate with the hitch pin secured in the aperture by the latch mechanism. The support plate rotates relative to the base plate with the hitch pin acting as a pivot point. Typically, grease or other lubricant is applied between the support plate and the base plate. The fifth wheel trailer is thus able to pivot relative to the tow vehicle about a vertical axis to facilitate cornering and parking. Normally, the hitch assembly is mounted directly over or a short distance in front of the rear axle of the tow vehicle in order to maintain proper weight distribution.
The vehicle most commonly used to tow fifth wheel trailers is a pickup truck having an 8 foot bed length. On such a truck, there is typically at least 53 inches between the centerline of the rear axle and the rear of the cab. The maximum width for a fifth wheel trailer is 102 inches as dictated by federal highway regulations, which amounts to 51 inches on each side of the pivot point. Thus, in order to prevent contact between the trailer and the cab during cornering, there must be at least 51 inches of clearance between the pivot point and the rear of the cab (sometimes more depending on the fore/aft location of the pivot pin relative to the front of the trailer).
Recently, there has been a consumer trend towards extended cab pickup trucks, which have longer, roomier cabs. These trucks have greatly expanded interior cargo volume and also have specially designed rear jump seats for accommodating additional passengers. Unfortunately, most of these extended cab pickups are built on a standard wheelbase chassis because consumers prefer the driving characteristics of a shorter truck, and accordingly, the bed of these trucks is typically 6 feet long rather than 8 feet long. Although these shorter bed pickups have the towing capacity to handle fifth wheel trailers, they do not have enough clearance between the axle and the rear of the cab to allow the trailer to pivot to 90 degree angle without contacting the cab, which could damage the truck and severely injure any occupants. In most circumstances, a fifth wheel trailer will contact the cab of a short bed pickup at angles much less than 90 degrees.
A number of approaches have been contemplated to adapt fifth wheel trailers to short bed pickup trucks, all of which have their drawbacks. One possible approach is to use a hydraulically operated sliding base to force the hitch assembly, and hence the pivot point, rearward away from the truck cab. Such a system would be expensive, difficult to maintain and would have to be driver actuated. Hence such a system would involve a significant delay or lag time. In an accident such as a jackknife such a system would operate too slowly to prevent the trailer from contacting and most likely damaging the cab.
Another approach, which also uses a sliding base, requires the operator to exit the truck, unlock the base, lock the brakes on the trailer and pull the truck forward. This temporarily moves the pivot point rearward so that the trailer can pivot relative to the truck to a certain extent without contacting the cab. However, before resuming driving, the driver must lock the trailer brakes, back the truck towards the trailer, again exit the truck and lock the sliding hitch, and return to the truck. Obviously, such a system is impractical in many situations, such as negotiating sharp turns in traffic, and is practically useless in an emergency.
Accordingly, there exists a need for an improved sliding hitch assembly that allows fifth wheel trailers to be towed using short bed pickup trucks, but which prevents contact between the trailer and the truck during normal operations. There also exists a need for a sliding hitch assembly that slides automatically in response to pivoting movement between the trailer and the tow truck and that does not require the expense, maintenance and lag time of hydraulic systems, and does not require the operator to exit the vehicle in order to lock or unlock the hitch assembly.
SUMMARY OF THE INVENTION
The sliding hitch assembly according to the present invention allows fifth wheel trailers to be towed safely and conveniently using short bed pickup trucks. The present sliding hitch assembly automatically moves rearward away from the truck cab in response to the pivotal movement between the trailer and the truck that typically occurs during normal driving situations such as cornering, parking, etc. The hitch assembly responds almost immediately to any turns, thus substantially eliminating any lag or delay, and no operator input is needed at any time. Thus in normal operating conditions, and even in many jackknife situations, the hitch assembly slides rearward far enough so that the trailer will not contact the truck cab.
The present sliding hitch assembly includes a sliding, rotating base plate that is mounted on a pair of rods. A lever arm extends from the base plate, and a cam follower attached to the end of the lever arm engages a stationary slot that extends substantially perpendicular to the rods. Any rotation of the base plate causes the cam follower to move within the slot towards one slot ends, which in turn causes the base plate to slide back and forth along the rods. Thus, as the base plate is rotated the base plate moves between a forward position, in which the cam follower is at the center of the slot, and a rearward position, in which the cam follower is near one of the slot ends. When in the forward position, the hitch pin receiving aperture, and thus the pivot point of the trailer, is directly or slightly in front of the axle centerline. As the base plate rotates relative to the truck, the lever arm mechanism causes the base plate to slide rearwardly on the rods, effectively moving the pivot point of the trailer away from the rear of the truck cab.
In order to effectuate this sliding movement, the sliding base plate must pivot relative to the truck in tandem with the trailer, and accordingly the connection between the trailer and the truck must be modified. As in the prior art, the base plate aperture includes a latch mechanism to receive and retain the hitch pin. However, the present base plate includes a rectangular cutout or depression surrounding the base plate aperture. The standard pin box is also modified by adding a rectangular locking plate to the support plate, with the locking plate effectively being concentric with the hitch pin. When the hitch pin is positioned in the base plate aperture according to standard practice, the locking plate on the pin box registers with and locks into the cutout in the base plate. Thus, when the trailer pivots relative to the tow truck during turning, cornering, etc., the support plate carried by the pin box and the base plate locked to the support pivot along with the trailer. Consequently, the lever arm mechanism described above moves the sliding base plate and thus the pivot point back and forth relative to the truck. Thus, no matter what position the trailer is in relative to the truck, the sliding base plate prevents the trailer from contacting the cab.
Accordingly, it is an object of this invention to provide an improved fifth wheel hitch assembly that allows fifth wheel trailers to be towed using short bed pickup trucks.
It is another object of this invention to provide a sliding fifth wheel hitch assembly that prevents the fifth wheel trailer from contacting the truck cab during normal operations such as turning or cornering.
A further object of this invention is to provide a sliding fifth wheel hitch assembly that moves automatically in response to pivotal movement of the trailer relative to the tow vehicle.
A still further object of this invention is to provide a sliding fifth wheel hitch assembly that requires no driver intervention and that does not have a delay or lag time.
These and other objects of the invention will become readily apparent to those skilled in the art upon a reading of the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary view in perspective of the sliding trailer hitch assembly according to the present invention shown installed in the bed of a pickup truck;
FIG. 2 is an exploded view in perspective illustrating the locking plate that secures the pin box to the base plate and also showing the lever arm assembly;
FIG. 3 is an elevational view in section taken substantially along line 3 — 3 of FIG. 1;
FIG. 4 is an elevational view in section taken substantially along line 4 — 4 of FIG. 1 showing the sliding support assembly, the support rods and the lever arm;
FIG. 5 is a fragmentary top plan view taken from above showing a fifth wheel trailer attached to a pickup truck using the sliding base plate body support assembly according to the present invention, in which the fifth wheel trailer is aligned with the pickup truck;
FIG. 6 is a top plan view similar to that shown in FIG. 5, but shown with the fifth wheel trailer turned relative to the pickup truck and illustrating the movement of the pivot point away from the rear of the cab;
FIG. 7 is a top plan view similar to that shown in FIGS. 5 and 6, in which the trailer is oriented at 90° relative to the pickup truck, and the pivot point is moved the maximum distance rearward away from the cab;
FIG. 8 is a fragmentary top plan view of the hitch assembly as it would be situated with the trailer in the position of FIG. 5;
FIG. 9 is a fragmentary top plan view similar to that shown in FIG. 8 but illustrating the configuration of the hitch assembly when the trailer is in the position of FIG. 6;
FIG. 10 is a top plan view similar to FIGS. 8 and 9, but showing the configuration of the hitch assembly when the trailer is in the position shown in FIG. 7;
FIG. 11 is an enlarged fragmentary view in perspective of the pin box to base plate connection shown in FIGS. 3 and 4, but with portions of the pin box cut away to reveal the support plate carried by the pin box interlocking with the cutout in the base plate;
FIG. 12 is an enlarged view in section of the pin box to base plate connection shown in FIG. 11;
FIG. 13 is a fragmentary view in perspective of a sliding trailer hitch according to a second embodiment of the present invention, illustrated installed in the bed of a pickup truck;
FIG. 14 is a detailed view of a portion of the hitch illustrated in FIG. 13, shown with the floor of the bed of the pickup truck broken away to illustrate the manner in which the hitch is secured to the truck;
FIG. 15 is an exploded view in perspective of the sliding trailer hitch illustrated in FIGS. 13 and 14; and
FIG. 16 is a top plan view of a portion of the hitch illustrated in FIGS. 13, 15 , and illustrating the manner in which the hitch members on the pickup truck and on the trailer are coupled together.
DETAILED DESCRIPTION OF THE INVENTION
The embodiment herein described does not intend to be exhaustive or to limit the invention to the precise form disclosed. It has been chosen and described to explain the principles of the invention and its application and practical use to best enable others skilled in the art to follow its teachings.
Referring now to the drawings, a sliding fifth wheel hitch assembly according to the present invention is generally indicated by the reference numeral 10 . Hitch assembly 10 is shown attached to the bed 12 of a pickup truck 14 according to common industry practice. Preferably, hitch assembly 10 is secured to the frame 13 . As shown in FIGS. 5-7, hitch assembly 10 is adapted to secure a fifth wheel trailer 16 to pickup truck 14 so that trailer 16 can pivot relative to pickup truck 14 about a pivot point 18 . A sliding hitch assembly 10 according to the present invention allows the pivot point 18 to slide in a rearward direction away from cab 20 and rearward from reference line “A” which is typically directly over, or in some circumstances slightly in front of, the center line of the truck axle (not shown), so that during all normal operating conditions the trailer 16 is prevented from contacting cab 20 of pickup truck 14 .
Referring now to FIGS. 1-4, hitch assembly 10 includes a base plate 22 having an aperture 23 therein for accommodating the hitch pin 24 which is attached to the pin box 26 of trailer 16 . Hitch pin 24 corresponds with pivot point 18 as will be discussed in greater detail below. Base plate 22 includes a mounting slot 28 which is oriented towards the rear of the truck as shown in FIG. 1 and which is used to guide hitch pin 24 into aperture 23 when mounting the trailer 16 to pickup truck 14 . Base plate 22 also includes a pair of internal latch members 30 , 32 which are actuated by release lever 34 in a manner commonly employed in the industry in order to secure hitch pin 24 firmly to base plate 22 thus securing trailer 16 to pickup truck 14 . A variety of readily available latching mechanisms as are well known in the art may be substituted for the mechanism shown. As shown in FIGS. 2, 11 and 12 , base plate 22 includes a rectangular depression or cutout 25 . A support plate 27 mounted to the underside of pin box 26 fits into the cutout 25 , which effectively prevents relative rotation between pin box 26 and base plate 22 , the purpose of which is described in greater detail below. Base plate 22 also includes a top surface 36 and a pair of pivot rods 38 , 40 that extend from the sidewalls 39 which extend downwardly from top surface 36 . Pivot rods 38 , 40 enable base plate 22 to be pivotally mounted to first intermediate support member 42 . First intermediate support member 42 includes a pair of support slots 44 , 46 which accommodate pivot rods 38 , 40 respectively, so that support base plate 22 can pivot relative to first intermediate support member 42 about the axis of pivot rods 38 , 40 in response to angular changes between trailer 16 and pickup truck 14 . Each slot 44 , 46 includes a pair of retention tabs 48 , and each tab 48 has a bore 50 therethrough for accommodating a cotter pin 52 , which is used to secure base plate 22 to first intermediate support member 42 by locking pivot rods 38 , 40 within their respective support slots 44 , 46 .
First intermediate support member 42 includes a front wall 51 and a rear wall 53 , each of which includes a bore 54 which extends perpendicular to support slots 44 , 46 . First intermediate support member 42 is in turn pivotally mounted to a second intermediate support member 56 . Second intermediate support member 56 includes a pair of vertical supports 58 , 60 mounted to a base member 62 . Vertical supports 58 , 60 each include a bore 64 therethrough for accommodating a threaded pivot bolt 66 . First intermediate support member 42 is received in the gap between plates supports 58 and 60 , and support member 42 is secured to second intermediate support member 56 by pivot bolt 66 . Pivot bolt 66 extends through 54 and 64 so that first intermediate support 42 is pivotable relative to second intermediate support 56 about the axis of bolt 66 . Bolt 66 is secured within bores 54 , 64 by threaded nut 68 . Accordingly, hitch pin 24 and hence trailer 16 is rotatable about mutually orthogonal axes in response to angular changes between trailer 16 and pickup truck 14 .
As shown in FIGS. 2 and 4, a pivot pin 70 connects second intermediate support 56 to a lever arm 72 which is slidably mounted within guide box 100 as discussed in greater detail below. The top end 74 of pivot pin 70 is welded or otherwise secured to the bottom face of base member 62 , while the bottom end 76 of pivot pin 70 is welded or otherwise secured to the pivot end 73 of lever arm 72 . Accordingly, any rotation of base member 56 produces a corresponding rotation in lever arm 72 . Slide plate 78 fits between lever arm 72 and second intermediate support 56 . Slide plate 78 includes a top surface 80 and a pair of downwardly depending endwalls 82 , 84 . Top surface 80 includes a hole 86 , which is sized to accommodate pivot pin 70 and bushing 88 which is provided to prevent binding between pivot pin 70 and slide plate 78 . Sidewalls 82 , 84 each include a pair of guide bores 90 which engage guide rods 92 to guide slide plate 78 back and forth as is discussed in greater detail below.
As shown in FIGS. 2, 3 and 4 , the entire structure consisting of base plate 22 , first and second intermediate supports 42 and 56 , slide plate 78 and lever arm 72 are supported by guide box 100 . Guide box 100 is bolted, welded or otherwise secured to frame 13 of pickup truck 14 by drilling holes (not shown 0 through bed 12 . Guide box 100 includes a bottom surface 102 , front and rear walls 104 , 106 , and left and right side walls 108 , 110 , having sloped portions 109 , 111 , respectively. Front and rear walls 104 , 106 each include a pair of holes 112 which support guide rods 92 , so that guide rods 92 extend through the interior of guide box 100 . A shear pin 114 at each end of guide rods 92 maintain rods 92 in guide box 100 , and enable rods 92 to be removed during assembly or disassembly or during servicing of hitch assembly 10 . Bottom surface 102 of box 100 includes a transverse slot 116 which extends generally perpendicular to guide rods 92 . Slot 116 includes a left and right ends 118 , 120 , and further includes a front edge 122 and a rear edge 124 . Lever arm 72 includes a cam roller 126 attached to cam end 127 of lever arm 72 through mounting bore 128 . Cam roller 126 engages slot 116 and cams against the edges 122 , 124 of slot 116 upon pivotal movement of lever arm 72 , which occurs upon rotation of pin box 26 and base plate 22 , thus causing slide plate 78 to slide back and forth along guide rods 92 . Accordingly, slide plate 78 is shiftable between a forward position in which plate 78 is disposed adjacent front wall 104 , and a rearward position in which plate 78 is disposed adjacent rear wall 106 of guide box 100 . When in the rearward position, cam roller 126 may be disposed adjacent either end 118 or 120 of slot 116 depending on the direction of rotation of lever arm 72 , which is dictated by the direction of rotation of trailer 16 relative to truck 14 . A pair of adjustment bolts 130 mounted through front wall 104 abut slide plate 78 when the plate is in the forward position. When slide plate 78 is in the forward position adjustment bolts 130 prevent inadvertent fore/aft movement of slide plate 78 .
In operation, with latch members 30 and 32 in an open position, a trailer 16 is mounted to pickup truck 14 according to standard practice by backing the pickup truck towards the trailer until the hitch pin 24 slides though slot 28 and into aperture 23 . In the process, support plate 27 slides into cutout 25 in base plate 22 . Upon actuation of lever 34 , latch members 30 , 32 close about hitch pin 24 , thus securing hitch pin 24 in aperture 23 and also securing pin box 26 to base plate 22 . At this point any relative rotation between pin box 26 and base plate 22 is prevented. The trailer 16 may then be towed in the normal manner by pickup truck 14 . When pickup truck 14 and trailer 16 encounter a turn in the road, trailer 16 pivots relative to pickup 14 and guide box 100 about a vertical axis which coincides with hitch pin 24 and pivot point 18 . When the trailer 16 turns relative to the truck 14 as shown in FIGS. 6 or 7 , base plate 22 , first and second intermediate supports 46 and 56 , and lever arm 72 also turn relative to pickup truck 14 . As shown in FIG. 9, rotation of trailer 16 relative to guide box 100 , which is fixed in the bed 12 of pickup 14 , causes cam end 127 of lever 72 to slide towards one of ends 118 , 120 of slot 116 . In the process, cam 126 presses against edge 122 of slot 116 causing a moment which draws slide plate 78 away from front wall 104 along guide rods 92 . In the process, the hitch pin 24 carried by base plate 22 move in a rearward direction away from the cab 20 of pickup 14 , thereby providing enough room for trailer 16 to pivot without contacting cab 20 of pickup truck 14 . When the truck/trailer combination straightens out and returns from the turned position shown in FIG. 6 or 7 to the straight position of FIG. 5, cam 126 presses against edge 124 of slot 116 , again creating a moment that urges slide plate 78 in a forward direction guided by rods 92 back towards front wall 104 .
Referring now to the alternate embodiment of FIGS. 13-16, elements the same or substantially the same as in the embodiments of FIGS. 1-12 retain the same reference character. Referring to FIGS. 13 and 14, the guide box 100 is secured to the bed of a pickup truck through ears 130 that extend from side walls 108 , 110 of the guide box 100 . Conventional angle brackets 132 are secured to side frame members 134 of the pickup truck that supports the bed 12 thereof. Conventionally, a pair of side frame members 134 extend substantially parallel to each other and support the truck bed 10 and are a part of the overall vehicle frame. As illustrated in FIG. 14, two angle brackets are secured to each of the side frame members 134 and are attached thereto by conventional fasteners 136 . Conventional fasteners 138 extend through apertures 140 on the ears 130 to secure the ears 130 to the brackets 132 . Clearly, if it is desired to remove the hitch 10 from the bed of the pickup truck, the fasteners 138 are removed and the hitch 10 can then easily be removed, leaving the substantially flat bed.
The pivot pin 70 in sleeve 88 illustrated in FIG. 2 is replaced in the embodiment of FIGS. 13-16 with an enlarged cylindrical boss 140 on the lever 72 . The boss 140 extends through a correspondingly sized aperture 142 in the slide plate 78 and is connected to second support member 56 by conventional fasteners 144 . The lever 72 includes a step-down portion 146 and an end portion 148 upon which cam roller 150 is rotatably mounted. The cam roller 150 engages and is guided by a track 152 which extends between the side walls 108 , 110 . The track guides the cam roller 150 as the second support member 56 is rotated by pivoting of the trailer with respect to the pickup truck to thereby move the slide plate 178 along the rods 92 in the same way as in the embodiment of FIGS. 1-12.
A modified support plate 154 is secured by conventional fasteners 156 to the bottom of pin box 26 which carries the king pin 24 . The hitch pin 24 extends through aperture 158 in support plate 154 and through mounting slot 28 and aperture 23 when the trailer is coupled to the truck. The support plate 158 includes a cutout notch 160 which is adapted to receive a projection 162 on a lever 164 when the trailer is coupled to the truck and the hitch pin 24 is received in aperture 23 . When this occurs, the support plate 154 is engaged with the top surface 36 of base plate 22 . The lever 164 is pivotally mounted on the base plate 22 by a pivot connection 165 .
The base plate 22 is provided with notches 166 , 168 . The handle 164 is provided with a rod 170 slideably mounted for movement within ears 172 extending from the lever 164 and is spring loaded toward the pivot 165 by a spring 174 . A lever 176 extends through elongated aperture 178 in lever 164 . Accordingly, the member 170 is urged into latching engagement with one of the slots 166 , 168 when the lever 164 is brought into either of the latching positions illustrated in solid and dotted lines in FIG. 16 . The member 170 may be withdrawn from its notch for movement toward the other notch by moving the member 176 toward handle 180 on lever 164 . When in the latched position with the member 170 engaged with the notch 166 and with the hitch pin 24 coupled in the aperture 23 , the projection 162 engages the notched recess 160 in support plate 154 to thereby prevent relative rotation between the hitch box 26 and the base plate 22 . However, when the lever 164 is moved to the dotted line position in FIG. 16 and with the member 170 engaged with the notch 168 , the projection 162 is moved out of the notched recess 160 , thereby permitting relative movement between the hitch box 26 and the base plate 22 , such as upon coupling and uncoupling the trailer.
It will be appreciated that the foregoing is presented by way of illustration only, and not by way of any limitation, and that various alternatives and modifications may be made to the illustrated embodiment without departing from the spirit and scope of the invention.
|
A hitch for coupling a trailer to a towing vehicle includes a first hitch member on the trailer and a second hitch member on the towing vehicle. The hitch member on the towing vehicle is mounted on a sliding mount extending across the rear axle of the vehicle. A linkage is responsive to pivoting between the trailer and towing vehicle to move the hitch on the towing vehicle toward the rear of the vehicle when turning is effected and to move the hitch on the towing vehicle just forward of the rear axle during normal longitudinal movement of the truck and trailer.
| 8
|
FIELD OF THE INVENTION
[0001] The present invention relates to water management during drilling, especially as relates to overhead drilling operations such as is typical in underground mines and tunnel construction. In particular, the present invention is concerned with apparatus for recovery and/or catchment of liquids used for cooling rock cutting tools such as rotary drill steels or bits and/or flushing drill cuttings from a bore hole.
BACKGROUND TO THE INVENTION
[0002] Overhead and rock face drilling is frequently performed in mining, in particular underground mining such as coal mining, and in the course of excavation, tunnelling and so forth.
[0003] Short and long bore drilling into a rock face or other material produces drill cuttings and other debris that require removal from the bore during drilling. Fines and dust particles are also created in the process, which need to be entrapped and prevented from freely escaping the bore and thus creating potentially hazardous dust clouds in a mine shaft or tunnel, in particular when coal seam mining.
[0004] Early attempts to address dust cloud creation in coal mining using purely air-cooled drilling steels and bits include the use of dedicated dust collector devices, generally comprising some form of dust confinement hoods or similar structures which are positionable at the rock face about the location of the bore to be drilled. An opening in the hood which allows passage of the drill string towards the capped-off bore location at the cutting face may or may not comprise some type of curtain or sluice structure to minimise egress of dust past the drill string from within the hood. A duct leading from within the hood provides a discharge to remove dust and cuttings created during drilling. These are extracted using forced air flow or suction devices, into a suitable receptacle/collection container. U.S. Pat. No. 2,634,952 (Brinkley) describes one such apparatus.
[0005] Equally applicable/transferable to mining/tunnelling operations involving drilling, U.S. Pat. No. 4,921,375 (Femulari) describes an anti-scattering device for the collection of waste material produced in the course of drilling, milling, grinding and similar machining operations, comprising a cylindrical or frusto conical bellows screen whose one open end can be secured to the front of the housing of the tool about the location where the chuck and drilling/milling/grinding bit protrude from the housing, and whose opposite open end (carrying an annular sealing ring), can be pressed against the surface to be machined, to seal off the space surrounding the cutting tool. A fan or vacuum device is in communication with the inside of the bellows structure to remove cuttings into a container that is coupled via a discharge tube to the inside of the bellows structure.
[0006] More commonly used nowadays are rock (and other strata) drilling apparatus and rigs which utilise liquids to (a) cool the drilling bit or cutting elements of the tool, (b) supress dust generation and (c) flush away the drill cuttings from short and long bore drilling holes. Many drill masts and rigs often employ hollow drill strings, which attach to a drill bit, or other rock/strata cutting tool, through which cooling/flushing/lubricating liquid is delivered to the cutting face. In some devices, the pressurised liquid passes through the drill motor, but in any event the flushing/cooling liquid is injected into and pumped through the hollow drill string, through the drill chuck and into or past the cutting device proper (steel of bit) to cool and/or lubricate the cutting elements at the drill face location.
[0007] The cooling/lubricating liquid, which may be simply water with or without additives, or a type of drilling mud, washes away the drill cuttings and fines out of the drill hole. Air-borne dust is thus avoided, though there is considerable ‘spent’ cooling/flushing liquid generated as a result, which represents a significant logistical compromise and environmental load, if disposed without treatment or otherwise re-cycled.
[0008] As an example, in some instances, it is not uncommon to use 1500 L/hour in drilling processes, which if not methodically collected and evacuated can quickly cause the surrounding ground to become unstable and hazardous. Such hazards are compounded by the difficulty of underground conditions.
[0009] Different cooling/flushing liquid management solutions have been suggested and/or used in the prior art.
[0010] One ad hoc solution, which is still widely used today, is to place a pan or basin of some sort directly below the drilling site, and use special pumps that are resistant to abrasion by the cuttings/fines entrapped in the flushing liquid, to convey the ‘spent’ liquid and the cuttings (also referred to as “drilling slurry”) into a separate facility for separating the liquid from the solids to a required degree of filtration.
[0011] As the drilling slurry contains drill cuttings of various sizes, it can be particularly difficult to pump this material, even using special slurry pumps. Conventional, general purpose water pumps can not be used, as these would malfunction under such operating conditions.
[0012] Another solution is to use dedicated drill liquid/drilling slurry collection structures in close proximity to the drilling hole location or otherwise carried at the drill rig, such as to receive most of the discharged drilling slurry. Some of these devices have an operating principle very similar to that of the Brinkley patent device.
[0013] For example, U.S. Pat. No. 7,726,417 (Larsson), assigned to Husqvarna A B of Sweden, describes a drill cooling water collecting device (collector) arranged above a drilling machine so as to capture drilling slurry and thus prevent it from running down and into the drill rig's motor, thus preventing damage being caused to the machine. The water collector comprises a squat, open-top cylindrical vessel having a flat bottom and a relatively short cylindrical side wall. The flat bottom has a draining hole connecting to an associated draining duct through which drilling slurry collected in the collector can be pumped for subsequent treatment/reclamation.
[0014] The water collector pan is used in conjunction with an anti-scatter screen, in form of a cylindrical bellows of smaller diameter than the collector pan, which surrounds the drill string that passes through a hole in the flat bottom in which a bearing and sealing structure for the drill string is received, and which extends all the way from the drill hole location (and thus drill bit/steel tip) to the water collector pan. The anti-scatter screen thus confines drilling slurry to drop towards the collector pan, catching most if not all the water for subsequent recycling. Other features are mentioned, but the water collecting arrangement described and depicted by Larsson suffers some limitations which compromise its practicality.
[0015] As is the case with the ad-hoc solution described above, special (and costly) suction pumps which are abrasion-resistant to drilling slurry, are required for draining away the liquid and drill cuttings that are gathered in the collector pan, towards a non-illustrated, separate liquid-cuttings separator tank or device.
[0016] U.S. Pat. No. 6,712,162 (Britz) describes a collector structure that is very much similar to that of Larsson (but for use in horizontal drilling applications) wherein, a squat cylindrical slurry collection pan is provided, which has a through hole in its flat base to allow passage, in sealing but movement-permitting manner, of a hollow-core, cylindrical drill bit. The rim of the cylindrical wall of the pan, which carries an annular sealing lip, can be pressed onto the cutting face and thus enclose the area surrounding the location where the drill bit is to cut a bore. The slurry draining port is located in the cylindrical wall and connects to a slurry discharge line.
[0017] The device of Britz thus obviates the need for a bellows screen to prevent scattering, as per Larsson. More relevantly, Britz illustrates a cooling/flushing liquid re-cycling circuit and system by way of which cooling/flushing liquid is recovered from the slurry. Two closed liquid holding tanks, a first on of which receives the slurry (and thus is a holding tank) and the second one of which houses a filtration device (and thus is a filtration unit) form part of the recycling circuit. A pressure pump is used to convey slurry from the first into the second tank. It will be noted that such arrangement, with its separate components still requires a special pump capable of pumping slurries with a potentially high drill cuttings and fines load. Given that the second filtration tank is a closed one, removal of the residual particulate material (ie the fines and cuttings) requires intermittent operation to effect cleaning and prevent clogging of the recirculation circuit.
[0018] An object of the present invention is to provide an apparatus for recovery of cutting tool cooling liquid/drill cuttings flushing liquid that at least ameliorates one or more limitations of existing approaches to managing spent rinse water arising from drilling operations.
[0019] Another object is to provide an apparatus that simplifies separation of drilling slurry into fractions comprising a liquid fraction that can be re-cycled substantially for re-use without filtration at a separate unit, and a slurry fraction comprising the bulk of solid particulates from the bore hole drilling operation.
[0020] Another object is to provide an apparatus of aforementioned type that can be easily retrofitted onto existing overhead rock drilling rigs and apparatus.
SUMMARY OF THE INVENTION
[0021] The present invention arises from the insight that drilling slurry from drilling operations can not only be advantageously collected close to the drill hole location, but can be effectively filtered in a purpose-designed collection device to a desired degree to obtain an effluent liquid stream that can be recycled into the cooling/flushing liquid supply for the drilling machine/rig. The drill cuttings and fines separated at the device, which represent a substantially ‘de-watered’, primarily particulate refuse stream, can be discharged to the ground surrounding the drilling rig, or into a separate container that can then be easily transported away from the drilling site to land fill or further processing.
[0022] The present invention in one aspect advantageously provides a drilling fluid recovery apparatus, comprising: a mounting structure shaped to allow removable mounting of the apparatus to a housing part of an overhead drilling apparatus; a funnel structure having a base with an aperture for passage of a drill steel or drill chuck of the drilling apparatus and having a slurry discharge port proximate the base, the funnel structure adapted for receiving a slurry mixture of drill cuttings and spent drill liquid produced during a drilling operation; and a spillway structure having at a lower end thereof a liquid catchment zone with a liquid discharge port and at an upper end thereof a liquid draining zone with a filtering grate operatively fitted thereto at an inclined angle vs the vertical, the spillway structure arranged such that slurry mixture exiting the slurry discharge port from the funnel structure gravity feeds onto an upper end and upper side of the filtering grate to move along the filtering grate towards a lower end for discharging from the spillway structure while liquid is drained from the slurry mixture towards the liquid catchment zone located underneath the filtering grate.
[0023] One advantage which the presently devised drilling fluid recovery apparatus provides is that there is no need for a bellows-like skirt to surround the drilling zone between the drill liquid catchment pan and rock face, as per the Larsson patent document. The drill chuck remains open to visual inspection to operators, and can be readily changed as required. Furthermore, adding, swapping or removing drill steels is relatively straightforward, as the apparatus does not prevent access to the drill chuck.
[0024] The filtering grate of the spillway structure will advantageously comprise a plurality of rods arranged in a grid, preferably an orthogonal grid of square or rectangular cross-section steel rods, wherein the spacing between lengthwise and width-wise running rods can be chosen to be the same or different. The spacing between the width-wise extending rods may also be varied along the extension of the grate from its upper, slurry receiving zone towards the lower, slurry discharging zone, to cater for hydraulic changes in the slurry as liquid is drained away as the ‘dewatering’ slurry spills/moves under gravity influence along the grate.
[0025] Advantageously, the funnel structure will be dimensioned to have an internal volume that is sufficient to temporarily receive and store drill cuttings and spent drilling liquid expected during a drilling operation, without overspilling, while simultaneously discharging the slurry towards the spillway for liquid removal.
[0026] To this end, the funnel structure may advantageously comprise a removable collar extension with a vertical peripheral wall, mountable to the open top end of a lower funnel section having at least in part inclined inner faces terminating at the base of the funnel structure. The collar can advantageously be formed of a resilient material which is transparent or at least translucent to permit ready visual inspection. Further, the slurry discharge port of the funnel structure will preferably communicates with a conduit pipe for draining the funnel structure into the spillway in controlled manner, the pipe's dimensions being chosen such that an expected, predetermined amount of drill cuttings and spent drilling liquid can be discharged at a defined flow rate without blockage.
[0027] A wide mesh or grate guard of suitable size can advantageously be fitted inside or above the open top end of the funnel structure, to avoid ingress of rocks above a certain size amongst the drill cuttings, which might otherwise block the funnel.
[0028] In a particularly preferred form, the spillway can have, at least in part, a duct-like channel configuration, with opposite vertical side walls and a rear wall spanning the side walls forming a vertical, u-shaped, front-side open channel. The filtering grate having a flat, planar configuration is then located to extend between the side walls in inclined fashion from near an upper end close to the rear wall towards a lower end distant from the rear wall and flush with a vertical front wall spanning the side walls and which closes the u-channel to define an enclosed zone below the liquid catchment zone located underneath the filtering grate; in other words, the filtering grate provides a front side closing the u-channel, but in inclined manner, separating the front where the slurry cascades downwards as consequence of the incline of the grate, and the liquid catchment part at the rear of the duct.
[0029] Advantageously, an upper end of the spillway structure may comprise a removable access door, fitted opposite the location where the slurry discharge port/conduit pipe drains into the spillway/is located. This allows an operator to have access to unblock the pipe/port if required. The inside of the door acts as a ‘splatter’ element to diffuse and distribute the incoming slurry prior to it being deposited onto the filter grate.
[0030] A baffle is advantageously positioned in an upper end of the spillway, opposite the outlet of the slurry discharge conduit pipe to moderate flow of the slurry mixture onto the filtering grate in the spillway. The baffle is preferably formed of a resilient material, and advantageously provided in the form of a concave strip running over the entire width of the spillway. Advantageously, the baffle can then be mounted in removable manner at the access door. The baffle in this form assists in spreading the slurry being discharged from the pipe and scattered against the removable door (access plate) into a more uniform band of slurry from where it cascades onto the filtering grate (which may also be called a screen) fitted to the spillway. This also allows one to use filtering grates of smaller dimensions in the cascading direction (flow or length direction) as a more spread-out flow is achieved over the width of the grate right at the top of it.
[0031] The liquid catchment zone of the spillway is advantageously provided with or connected to a rain water head structure, with or without an additional filtering mesh, which in turn drains to a downpipe for directing the liquid removed from the slurry to further use or discharge.
[0032] The filtering screen (grate), which is preferably a planar grate structure comprising of traversing and intersecting square cross-section rods, is advantageously angled in the spillway at between 45° and 65° to a horizontal plane, and more preferably at approximately 55° to a horizontal plane, so that the slurry mixture cascades down the filtering grate in a controlled manner as it is ‘dewatered’ prior to discharge of the ‘dewatered’ drill cuttings.
[0033] It will be understood that the grate is designed to remove a substantial part of the liquid, without fully filtering the reclaimed liquid of drilling fines. The reclaimed liquid may carry fines in suspension of an average particle size which does not substantially impede pumping of the liquid using conventional eg ring pumps as used in overhead drill rigs to supply flushing water ((liquid) via the drill bit into the bore for flushing the cuttings out of the bore.
[0034] The present invention thus in another but related aspect provides a system for recovering bore hole flushing or rinse fluid from drilling slurry comprised of drill cuttings and liquid obtained in a strata drilling operation, comprising an apparatus as described above, mounted atop an overhead drilling rig, a drainage pipe connected to the apparatus for receiving fluid drained by the apparatus from the slurry mixture, a holding tank connected to the drainage pipe for temporary storage of drained liquid, plumbing connecting the storage tank to the drill rig flushing liquid supply line(s), and a pump for pumping drained liquid from the holding tank via the plumbing to the drill rig for re-use in bore hole drilling.
[0035] In yet a further aspect, the invention also provides an overhead drill rig with recycled borehole flushing water delivery arrangement, comprising an overhead drilling rig with a drill motor and drilling tools, an apparatus as above described, a drainage pipe connected to the apparatus for receiving liquid drained from the slurry mixture via the liquid catchment zone located underneath the filtering grate of the apparatus, a holding tank connected to the drainage pipe, and a water pump for delivering reclaimed liquid stored in the holding tank to the drill motor for re-use during a drilling operation.
[0036] Further aspects of the present invention, and preferred and/or optional features thereof will become apparent also to the skilled reader from the following description of a preferred embodiment which is provided with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIGS. 1 and 2 are perspective views of an apparatus according to an embodiment of the invention, as seen from offset angles from the front and rear of the apparatus.
[0038] FIG. 3 is an exploded view depicting components of the apparatus of FIGS. 1 and 2 , as viewed from the front perspective view of FIG. 1 .
[0039] FIG. 4 is a front elevation of the apparatus of FIGS. 1 and 2 , with an access door and filtering screen of the apparatus removed.
[0040] FIG. 5 is a top plan of the apparatus of FIGS. 1 and 2 .
[0041] FIGS. 6A and 6B are cross-sectional views of the apparatus of FIGS. 1 and 2 , from respective sides of the apparatus. FIG. 6A depicts a cross-sectional view through a centre line of the apparatus, while FIG. 6A depicts a cross-sectional view at a minimal offset from a near side of the apparatus.
[0042] FIGS. 7A and 7B are a front elevation and associated cross-sectional view through a centre line of the apparatus installed in situ atop a housing for a drill motor, around a drill chuck extending from the drill motor housing, and with a drainage hose leading away from the apparatus.
[0043] FIGS. 8A and 8B are associated perspective and front elevation views of a chamfered drill chuck for use with the apparatus of FIGS. 1 and 2 , as depicted in FIGS. 7A and 7B , with hidden lines depicted in dash in the front elevation of FIG. 8B .
[0044] FIG. 9 depicts a system for reticulating drill water embodying the apparatus of FIGS. 1 and 2 , shown in a cross-sectional view corresponding to that of FIG. 7B , which depicts a detail of FIG. 9 .
DESCRIPTION OF PREFERRED EMBODIMENTS
[0045] Referring first to FIGS. 1, 2 and 3 , reference number 10 identifies an apparatus for recovery of liquid (hereinafter simply referred to as water) employed during an overhead drilling operation into strata (eg a rock face) for flushing out drill cuttings (fines, rock pieces, dust etc) as drilling is performed with a rock drilling rig, and cooling the drill tool head (drill bit or steel) according to one particular preferred embodiment of the present invention.
[0046] The apparatus 10 comprises principally a funnel structure 12 , a mounting structure 14 and a spillway structure 16 , integral with one another. For ease of reference, relative terms such as front, rear, side, upper, lower, etc, will be used also to facilitate understanding. It will thus be noted that funnel structure 12 is located at the top above the mounting structure 14 and the spillway structure 16 is located directly adjacent on the front but offset and below the funnel structure 12 .
[0047] Before describing the apparatus 10 in further detail, it is instructive to briefly review its application in context, as depicted in FIGS. 7A and 7B, and 9 . The apparatus 10 is, as depicted, mounted at the housing 22 on top of a drill motor 18 , which has a drill chuck 20 projecting upwardly, of an overhead drilling rig (not shown). The apparatus 10 is devised to capture the slurry mixture of drill cuttings and spent bore hole flushing (or rinse) water that falls during an overhead drilling operation and which otherwise would impact on and run down the side of the drill rig 22 . A drainage hose 24 connected to apparatus 10 removes spent rinse water drained from the slurry mixture collected by apparatus 10 .
[0048] Overhead drilling rigs will not be described herein any further, and reference should be made to appropriate literature. The broad principle of operation of apparatus 10 is to collect the slurry mixture of spent rinse water and drill cuttings as this heterogeneous mass falls—and remove a substantial part of the spent rinse water from the drill cuttings, which are discarded, while the recovered spent rinse water is drained away for collection in a sedimentation or storage tank 26 from where it can be extracted through pipe 28 by a normal water suction pump 30 (as compared to specialist slurry pumps used in mining) for recirculation via suitable pipe work (plumbing) 32 for re-use as flushing water for a drill string and bit. The collected spent rinse water can be stored and continuously reticulated, as depicted, or drained—or pumped away as waste as requirements dictate. Apparatus 10 is devised to drain water with some fines in it, ie not to entirely filter the spent rinse water at the apparatus of all particulate matter above a certain particle size. Discarding the drill cuttings from the slurry to a relatively fine level at the apparatus is sufficient to allow reliable pumping using general-purpose pumping equipment, avoiding pump failure which can otherwise occur if particulate matter such as drill cuttings is attempted to be pumped using conventional water pumps.
[0049] Returning to FIGS. 1 to 3 , funnel structure 12 comprises a lower funnel pan 34 having an upright back wall 36 , an inclined, partially frustoconical wall 38 and an annular base part 40 with a circular central aperture 42 for accommodating and allowing passage from below the base of drill chuck 20 (as depicted in FIGS. 7A and 7B ). It will be noted that the funnel structure 12 overall is not strictly speaking frustoconical in mathematical or geometrical sense, and does not imply that the funnel is exactly or even approximately circular in shape, but only that it defines an receptacle zone with a substantial part of the inward facing surface inclined to direct material towards the base part 40 . The top edge of lower funnel pan 34 is in fact not circular but is clipped at its rear. This is not of any especial significance, beyond the fact that this particular configuration is adopted so that the funnel section 12 , in plan view, not exceed the footprint of the drill motor housing 22 to which the apparatus 10 is fitted (as best seen in FIG. 7B ).
[0050] The funnel pan 34 provides a lowest drainage point for slurry mixture falling into and collected by the funnel structure 12 , as is noted below.
[0051] Within the aperture 42 of annular base part 40 there is located and seated a circular gasket 44 , which serves to seal the funnel pan's bottom against the head part of the drill housing 22 from leaking slurry mixture onto the drill motor 18 located beneath the apparatus 10 .
[0052] As noted, whilst the mayor part 38 of the side wall of funnel pan 34 is generally angled upwardly and outwardly from the flat annular base part 40 , a minor portion of the funnel sidewall 36 is angled vertically at the rear. It will be furthermore noted that the uppermost terminal rim portion 46 of the inclined wall 38 also extends vertically. This portion 46 serves to help collect slurry mixture, and permits convenient and secure fitting of an optional, removable collar 48 , which has a footprint of similar contour as the open top of funnel pan 34 and by way of which the volume of funnel section 12 can be increased by vertically extending the peripheral walls 36 , 38 upwards.
[0053] The collar 48 is secured by a suitable clamp or tie, and is preferably made of a hard-wearing, transparent (or translucent) and resilient rubber-like material, such as a silicone or urethane based material. This permits ready visual inspection into the funnel 12 , and can be replaced as required if damaged or worn. In contrast, the remainder of funnel section 12 is made from suitably gauged steel sheet material.
[0054] The open mouth (top) 50 of lower funnel pan 34 is preferably covered by a wide gauge grate 52 that is supported at discrete horizontally extending lugs 54 welded onto inclined and upright side walls 38 , 36 of pan 34 . The gauge of grate 52 is selected to catch rocks that may be fall with drill cuttings into the funnel section 12 . The contour of grate 52 is best seen in FIG. 3 , and is shaped to fit inside the funnel section 12 , and match the central aperture 42 in the annular base part 40 of funnel pan 34 and the profile of the funnel sidewalls. The gauge of the grate 52 is selected to pass all but the largest drill cuttings—and in the preferred embodiment is formed as grid spaced at approximately 25 mm by 25 mm. Such larger pieces of material may cause blockages during operation, and accordingly are best caught before attempting to pass through the funnel section 12 . Periodically clearing the grate 52 by hand removes further impediment from outsized pieces trapped by the mesh 210 .
[0055] Slurry mixture falling to and captured by funnel section 12 is passed to the adjacent spillway section 16 via cylindrical pipe stump 56 , which is welded to the outside of inclined wall 38 about or within a corresponding circular port (or through hole) provided in the inclined funnel sidewall 38 at the front and centre of the apparatus. The lowest extent of cylindrical pipe stump 56 is flush with the funnel pan 34 , ie the annular base wall 34 , to avoid collecting excess slurry mixture within the funnel pan 34 . The diameter of the conduit (pipe stump) 56 is approximately 40 mm, though a variety of other configurations and dimensions may be used. The conduit 56 terminates within the spillway section 16 , where slurry mixture from the funnel section 12 is discharged.
[0056] The spillway section 16 comprises a duct-like vertical structure 58 with three closed wall components, a rear wall 60 and two side walls 62 , 64 which define an essentially bracket or angular u-shaped vertical channel or through 66 open to the front side of apparatus 10 . Duct-like vertical structure 58 in the preferred embodiment extends vertically, and in use is positioned against a vertical side of the housing 22 of the drill motor 18 . This ensures that the apparatus 10 has a compact footprint.
[0057] The spillway sidewalls 62 , 64 are flush with and formed integrally with side skirts 67 , 68 that extend downwardly from and at the sides of the funnel section 12 . The skirts 66 , 68 form part of the mounting structure 14 of apparatus 10 in that they serve to locate the apparatus 10 relative to the drill motor housing 22 .
[0058] At an upper end of spillway section 16 , where the spillway sidewalls 62 , 64 meet the funnel section 12 , there is mounted a 90 degree curved access door 70 positioned to span between the sidewalls 62 , 64 . The access door 70 has a handle 72 , and is conveniently retained in place to close the upper end of spillway channel or through 66 by an interference fit, and also with assistance from retaining clips 74 or similar fixtures that are fitted in association with co-operating lugs 76 extending from the sidewalls 62 , 64 .
[0059] The access door 70 (as best seen in FIG. 3 ) is shaped to fit flush with the edges of the side walls 62 , 64 of spillway section 16 and has a rearwards located arcuate edge so that it can fit flush against an outer surface of the partially frustoconical inclined sidewall 38 of lower funnel pan 34 . The access door 70 curves down from its horizontal rear portion to its vertical front portion such as to be located horizontally displaced from the terminal end of slurry discharge pipe stump 56 . Thus, access door 70 serves the double purpose of providing a splatter surface for slurry discharged from pipe stump 56 and allow access to it in case of blockage.
[0060] The access door 70 has attached to its lower terminal front edge via mounting angle 77 , a resilient but otherwise form-stable baffle 78 . As best seen in FIG. 6A , the baffle 78 is provided as a concave strip of material, (or lip) curved slightly upwardly and extending in rearward direction towards the rear wall of spillway section 16 to end about level with the discharge location of pipe stump 56 . Baffle 78 thus provides a channel extending width wise between the spillway side walls 62 , 64 by way of which the slurry discharged from pipe stump 56 and splattered by the inner, curved face of door 70 is caught and spread along the width of the spillway, and subsequently discharged curtain-like into the vertical channel/through 66 of the duct-like structure 58 . The baffle 78 moderates and to a practical extent controls flow of incoming slurry mixture, so that the incoming slurry mixture is collected by the baffle 78 , and then with the continual arrival of slurry mixture spills over the free rim of baffle 78 into spillway duct 66 .
[0061] It will be noted from FIGS. 3 and 6 a - 6 b in particular, that an inclined filtering (in the sense of de-watering) grate (or screen) 80 is mounted within through 66 between the side walls 62 , 64 such as to subdivide the channel 66 into a portion 66 a that is open towards the front of apparatus 10 and a rear portion 66 b, serving as a liquid catchment zone for water separated at the grate 80 from the mixed slurry that is discharged onto it by baffle 78 . The upper edge of grate 80 is supported at suitably shaped locating bars, schematically illustrated at 82 , 83 , positioned horizontally spanning the spillway sidewalls 62 , 64 , whereas the lower end is equally supported at locating bar 84 such that grate 80 can be inserted and removed from channel 66 as and when required. The planar dimensions of grate 80 are chosen such that it can fit snuggly between the spillway side walls 62 , 64 and extend from near spillway rear wall 60 just below the terminal edge of baffle 80 at an angle towards a vertically extending front wall 86 at the lower end of the duct-like vertical structure 58 . Thus, slurry mixture discharged onto the de-watering grate is cascaded along the grate 80 for discharge at its lower end and along vertical front wall 86 .
[0062] The filtering screen (dewatering grate) 80 is preferably simple and robust in construction, and in the preferred embodiment consists of a series of spaced apart rails connected by a series of underlying spaced apart studs. The pitch of the rails is relatively tight, and each rail is approximately 1.5 mm in width, with adjacent edges spaced apart by a comparable amount. The rails have a depth of approximately 2 mm, and with sufficiently heavy studs the screen 80 is suitably robust. The grate 80 in basic configuration is evocative of window louvres, or a cattle grid in miniature. A variety of different configurations may be used to achieve a desired rate and amount of dewatering of the mixed slurry, as a matter of trial and experimentation.
[0063] As noted, in operation of apparatus 10 , the slurry mixture spills from the baffle 78 onto an upper region of the dewatering grate 80 , into zone 66 a of the trough, and progressively runs down the screen towards its lower region. As it progresses, spent rinse water in the slurry mixture drains away through the rails of the grate 80 , and into the rearward liquid catchment zone 66 b of channel/through 66 of spillway 16 . Fine particles in the slurry mixture will also pass through the screen 80 , though larger particles will run down the screen 80 , and be discharged at the bottom of the screen 80 , at which point the slurry mixture is largely drained of spent rinse water.
[0064] With extended use of the apparatus 10 , the dewatering grate (screen) 80 wears as a consequence of the abrasive effect of slurry mixture and specifically the suspended drill cuttings rubbing against the screen. The leading edges of the rails become rounded slightly with use, which marginally reduces the efficiency of the grate 80 . The grate 80 is less able to effectively ‘cut’ into the slurry mixture as a consequence. A perceptible slowing of the drainage rate drainage can be noticed with careful observation. The grate 80 can be removed and replaced ‘upside down’ to expose the opposite (unworn) corners of the rails of the screen 80 . Should the screen 80 become worn in both orientations, the screen 80 can be substituted with a replacement if necessary. Specially engineered screens having greater complexity may be contemplated, but are not necessary for effective operation of the apparatus 10 .
[0065] The ‘water screening’ grate 80 is angled relatively steeply, and in the preferred embodiment approximately 55° from a horizontal plane. This angle permits a relatively compact footprint for the apparatus 10 whilst also effectively draining the slurry mixture. A broader range of angles is of course possible, with angles between 30° and 80° to a horizontal plane being feasible, and angles between 45° and 65° being favoured for reasons already mentioned. Should the angle be too steep there will be insufficient drainage, and too shallow an angle will tend to clog the screen 80 , and also extend the footprint of the apparatus 10 .
[0066] The grate 80 may appear to be particularly steep, but is found to be remarkably effective in efficiently draining slurry mixture in operation, with a high recovery rate of spent rinse water.
[0067] The apparatus 10 as a whole is advantageously fabricated from laser cut stainless steel, welded together. Use of a suitable gauge stainless steel plate results in a robust unit which is well able to resist corrosion and is unlikely to require in field repair, and which weighs of the order of 10 kg. Certain components as mentioned are desirably provided in a suitable rubber-like material, such as collar 48 , gasket 44 , and baffle 70 . Certain parts may require periodic replacement, such as the flexible components noted, as well as screen 80 , mesh 52 , and retaining clips 74 .
[0068] The spillway section 16 incorporates at its lower end a rain water head structure 88 similar to those found in many downpipes of roof gutter structures of houses. The discharge duct 90 from rain water head structure 88 extends outwardly and downwardly to connect to drainage hose 22 as shown in FIG. 9 . The rain head 88 is angled inwardly to collect the spent rinse water delivered from the spillway 16 , which is then delivered out the hose 22 .
[0069] FIGS. 7A and 7B depict use of the apparatus 10 in conjunction with a drill motor 18 . The tip of the drill steel typically terminates in a drill bit or other rock-working tool adapted for working the drilling surface.
[0070] The apparatus 10 in use is centred around the drill chuck 20 and resting atop the drill motor 18 . The drill motor 18 as depicted has a generally rectangular housing, with a flat top surface, and vertical sides.
[0071] The apparatus 10 is generally shaped to fit around the top surface of the housing of the drill motor 22 , and against a vertical side of the housing. The drill chuck 20 fits into the drill motor 18 for receiving torque from the motor and transferring to the drill steel. The drill chuck 20 can freely rotate within the apparatus 10 owing to the central aperture 42 of the lower funnel base 34 .
[0072] During operation, pressurised rinse water is fed through the housing of the drill motor 18 , through the drill chuck 22 , and into the hollow interior of the drill steel. When working a rock face of the like, the rinse water is forced through the end of a dill bit attached to the drill steel, and rinses away drill cuttings and fines, and any other dirt, debris or vegetative material that is scored by drilling. The spend rinse water, mixed with the drill cuttings and the like, forming a slurry mixture as described, falls from the working surface downwards adjacent the drill steel.
[0073] A typical site uses a hydraulically-driven mast which tracks adjacent the drill steel. At the drilling site working surface, a timber jack and attached plate is pressed and holds firm up against the surface surrounding the drilling site to be drilled by the drill bit. A jawed clamp attached to the mast is used to hold the drill steel when required—such as when a further drill steel is to be added or swapped or removed. The drill steel is driven by the chuck 20 by means of a square brace arrangement which allow for torque transfer from the motor via the chuck 20 .
[0074] A rubber shroud (not shown) may optionally be provided and attached to the accompanying mast, and disposed around the drill bit or drill steel at or near the working surface as drilling takes place. This can assist in collimating the mixture as it falls. Moreover, one can minimise the spent rinse water and drill cuttings from flying too far afield, and containing most of the mixture to a relatively confined perimeter within a contained radius from the drill steel.
[0075] While the drill steel is implied as operating in a dead vertical orientation, it can in fact operate at an angle. The apparatus 10 can accommodate such angles, though the use of the collar 48 as described may need to modified or removed to assist in collecting as much spent rinse water as practicable.
[0076] FIGS. 8A and 8B are provided for completeness, and provide views of an exemplary drill chuck 800 used in proximity to the apparatus 10 . The drill chuck 800 comprises a chuck head 810 , and extending along a longitudinal axis of the chuck head 810 a shank 820 which is circular in cross-sectional profile. Disposed along the shank 820 is a brace 830 , which as depicted is of square-profile, and is adapted to fit in a matching recess in a drive piece of the drill motor. The shank 820 and brace 830 are conventional in construction, and used to transfer torque from the drill motor to the chuck 800 and thence to a drill steel, associated rock working tool, and ultimately the working face of the rock.
[0077] FIG. 9 depicts an integrated system 100 which relies upon the apparatus 10 to collect spent rinse water. The drainage hose 24 is connected at one end to the downpipe attached to the rainhead 88 of the apparatus 10 . At its other end the drainage hose 24 discharges spent rinse water to a (schematically depicted) holding tank 26 . A pump 30 (also schematically depicted) and associated feed hose 28 removes spent rinse water from the holding tank, and pumps to back via return line 32 to the drill motor 18 to reuse. Any suitable general-purpose pump may be used, whilst the spent rinse water circling through the system 100 will not be clear, filtering by the apparatus 10 ensures that drill cuttings of sufficient size to inhibit reliable operation is largely removed. The pump 30 should be suitably rated, and adequate to sustain the desired flow rate—an indicative exemplary flow rate 1500 L/hour is mentioned above.
[0078] As a proportion of the rinse water is inevitably lost during operation, provision for injecting supplementary water (for example, into the holding tank 26 ) is advantageously provided—such as via a pressurised inlet and control float, for example, or any other suitable means.
[0079] A reticulation circuit is thus formed and requires the circulation of far less water than if spent rinse water is simply left to soak into or collect around adjacent ground.
[0080] While the apparatus 10 and system 100 described and depicted herein is presented according to one particular preferred embodiment, there are in fact many varied alternative forms the present invention can be embodied. Various additions, modifications and substitutions regarding design and construction can be made without departing from the spirit and scope of the invention.
|
An apparatus ( 10 ) for handling drill water comprises a funnel ( 12 ) and a spillway ( 16 ) which act in concert to receive and then separate a slurry mixture into constituent drill cuttings and spent rinse water. The funnel ( 12 ) collects the falling slurry mixture, which is channelled via conduit ( 56 ) into a spillway ( 16 ). The spillway ( 16 ) is fitted with a dewatering grate ( 80 ) onto which the slurry mixture from the funnel ( 12 ) is channelled. The flow of slurry mixture is moderated by a baffle ( 78 ) which both catches and discharges slurry mixture delivered by the conduit ( 56 ). The slurry mixture is discharged over the dewatering grate ( 80 ), which drains the spend rinse water into a section of the spillway ( 16 ), and discharges the drill cuttings away from the grate ( 80 ).
| 4
|
BACKGROUND OF THE INVENTION
[0001] (1) Field of the Invention
[0002] The present invention relates to a wet medicated sheet in which medicinal agents containing electrolytic or non-electrolytic pharmaceutical ingredients are impregnated or applied on the medication surface to be placed on the skin.
[0003] (2) Description of the Related Art
[0004] The wet medicated sheet in which the medicinal agent is impregnated or applied on the medication surface to be placed on the skin so that the pharmaceutical ingredients can be absorbed into the body from the skin is widely used to treat nerve pain, shoulder stiffness, and the like as easy and convenient treatment means. However, in the conventional medicated sheet, only about 20 to 30% of the pharmaceutical ingredients are absorbed from the skin at the most, and thus the absorption efficiency of the pharmaceutical ingredients is known to be low.
[0005] One of the inventors of the present invention first developed, as an electrical treatment equipment using ion infiltration effect of the pharmaceutical ingredients by current flowing through the skin, an equipment in which an outer surface of an electrode on one surface of a flat compact battery and a peripheral side surface of the battery are covered with an external capsule material by way of a desired gap, the relevant electrode and another electrode are insulated with an insulating material, a medicinal agent having fluidity added with conductivity is filled to the gap, the open portion at the peripheral side of the gap is sealed with a strippable sheet, and the other electrode surface stripped with the sheet is contacted to the skin in time of use (see Japanese Patent Publication No. 3-69545), and then developed, as an electrical treatment equipment that can be used by simply being attached to the medicated sheet in which the medicinal agent containing electrolytic pharmaceutical ingredients, which ionize, is impregnated or applied on the medication surface, and that enhances the absorption efficiency of the pharmaceutical ingredients of the medicated sheet, an electrical treatment equipment in which a battery is formed with an electrolytic solution interposed between a positive electrode plate to be attached to the medication surface of the medicated sheet and a negative electrode plate to be contacted to the skin, and the outer peripheral part between the electrode plates is sealed with an annular seal member having insulating property (see Japanese Laid-open Patent Publication No. 2005-192848).
[0006] Recently, it is reported that the absorption of the pharmaceutical ingredients can be accelerated by the convection flow of water that occurs by flowing current to the skin through the use of the electrical treatment equipment as described in Japanese Laid-open Patent Publication No. 2005-192848 even with the medicated sheet that uses that medicinal agent containing non-electrolytic pharmaceutical ingredients dissolved or dispersed in a solvent (see Seiji, Higo “Regarding recent development trend of Transdermal Drug Delivery System”, YAKUGAKU ZASSHI, The Pharmaceutical Society of Japan, 2007, Vol. 127, No. 4, p. 655-662).
[0007] To further enhance the absorption efficiency of the electrolytic and non-electrolytic pharmaceutical ingredients, the inventors of the present invention developed an electrical treatment equipment and a medicated sheet in which a microscopic pin holder-shaped projection is arranged on the skin contacting surface of the electrode plate, and the pharmaceutical ingredients are injected along the pin holder-shaped projection to be inserted under the skin (see Japanese Patent Publication No. 4170307, Japanese Laid-open Patent Publication No. 2009-136383, and Japanese Laid-open Patent Publication No. 2009-142432). The electrical treatment equipment described in Japanese Patent Publication No. 4170307 includes the pin holder-shaped projection on the skin contacting surface of the positive electrode plate made from stainless steel or the negative electrode plate made from titanium. Furthermore, the medicated sheet described in Japanese Laid-open Patent Publication No. 2009-136383 and Japanese Laid-open Patent Publication No. 2009-142432 has a pair of electrode plates, made from two types of metals having different normal electrode potential difference or subjected to metal plating, attached to the medication surface impregnated or applied with medicinal agent so as to be insulated from each other, where the pin holder-shaped projection is arranged on the skin contacting surface of one or both electrode plates.
SUMMARY OF THE INVENTION
[0008] The electrical treatment equipment described in Japanese Patent Publication No. 4170307 and the medicated sheet described in Japanese Laid-open Patent Publication No. 2009-136383 and Japanese Laid-open Patent Publication No. 2009-142432 have a microscopic pin holder-shaped projection arranged on the skin contacting surface of the electrode plate, and thus can significantly enhance the absorption efficiency of the pharmaceutical ingredients by the injection effect to under the skin by the pin holder-shaped projection, and medicinal agents such as anesthetic drugs and vaccine that are conventionally injection-administered using a syringe can be injection-administered other than medicinal agents of anti-inflammatory analgesic plaster. However, the electrode plate with the pointed pin holder-shaped projection like the syringe needle becomes a dangerous medical waste after use, and the problem arises in that it cannot be safely discarded by incineration since the electrode plate that becomes the dangerous medical waste is made from metal or is subjected to metal plating.
[0009] It is an object of the present invention to safely discard the electrode plate with a pin holder-shaped projection of the medicated sheet by incineration.
[0010] To solve the above problem, the present invention adopted a configuration of a medicated sheet in which positive and negative electrode plates, which are insulated from each other, are arranged on a medication surface of a medicated cloth impregnated or applied with medicinal agent, and microscopic pin holder-shaped projections are arranged on a skin contacting surface of at least one electrode plate to be contacted to the skin, wherein the electrode plate including the pin holder-shaped projections is made from a conductive resin.
[0011] In other words, the electrode plate including the pin holder-shaped projections is safely discarded by incineration by forming the electrode plate including the pin holder-shaped projections from a conductive resin. The pharmaceutical ingredients of the medicinal agent may positively ionize, negatively ionize, or may not ionize, where the electrode plate that contacts the skin is preferably negative if the pharmaceutical ingredients positively ionizes and the electrode plate that contacts the skin is preferably positive if the pharmaceutical ingredients negatively ionizes.
[0012] The conductive resin can be obtained by mixing a conductive substance to a thermoplastic resin.
[0013] The incineration efficiency can be enhanced if the conductive substance is carbon black.
[0014] The pin holder-shaped projections of the electrode plate made from the conductive resin are made through an injection-molding method, so that the electrode plate including the pin holder-shaped projections can be efficiently and inexpensively manufactured.
[0015] The height of the pin holder-shaped projection is preferably between 50 and 600 μm. The skin is made up of a keratinous layer, an epidermis including living cells, and a dermis where capillary blood vessels and nerves are present from the surface side, where the height of the projection is preferably about 50 to 150 μm when injecting the pharmaceutical ingredients of an anti-inflammatory analgesic plaster, and the like to the epidermis, and the height of the projection is preferably high or about 150 to 600 μm when injection-administering the pharmaceutical ingredients such as vaccine to the dermis. In the case of injection-administering the pharmaceutical ingredients to the dermis, the medicated sheet is made disposable so as to eliminate the possibility of bacterial infection, and the like from the capillary blood vessel of the dermis.
[0016] One of the positive or negative electrode plates is made from a conductive resin including the pin holder-shaped projections, and the other electrode plate is made from metal having a normal electrode potential difference with the one electrode plate made from the conductive resin or is subjected to metal plating, or is made from a conductive resin mixed with a conductive substance having a normal electrode potential difference with the one electrode plate, so that current that passes through the skin and the medicinal agent of the medication surface is generated between the electrode plates by the potential difference between the positive and negative electrode plates, a separate battery becomes unnecessary, and incineration can be facilitated. If the other electrode plate is also made from a conductive resin mixed with the conductive substance, the entire medicated sheet can be incinerated as a whole.
[0017] If the conductive substance to be mixed to the conductive resin is carbon black, the normal electrode potential becomes high or the same extent as the noble platinum. If the conductive substance is a metal filler, or the like, it becomes the normal electrode potential of the relevant metal. Therefore, the conductive resin that uses carbon black for the conductive substance is preferably for the positive electrode plate. In this case, the negative electrode plate may be made from a base metal such as zinc and magnesium having low normal electrode potential or may be subjected to plating of such base metal, or may be made from a conductive resin mixed with base metal filler, and the like.
[0018] An overlapping margin portion is arranged at the positive and negative electrode plates, and an electrolytic solution is interposed between the positive and negative electrode plates at the overlapping margin portion, so that the battery is formed at the overlapping margin portion of the positive and negative electrode plates and the current that passes through the skin can be actively generated.
[0019] The current that passes through the skin can be actively generated even by applying voltage from an external power supply to between the positive and negative electrode plates.
[0020] The entire medicated sheet can be incinerated as a whole by forming both the positive and negative electrode plates from a conductive resin.
[0021] The medicated sheet of the present invention has the electrode plate including the pin holder-shaped projections arranged on the medication surface of the medicated cloth made from a conductive resin, and hence the electrode plate including the pin holder-shaped projections can be safely discarded by incineration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a longitudinal side view showing a medicated sheet of a first embodiment;
[0023] FIG. 2 is a traverse plan view taken along a line II-II in FIG. 1 ;
[0024] FIG. 3 is a longitudinal side view showing an overlapping margin portion of the positive and negative plates in FIG. 1 in an enlarged manner;
[0025] FIG. 4 is a longitudinal side view showing a medicated sheet of a second embodiment;
[0026] FIG. 5 is a traverse plan view taken along a line V-V in FIG. 4 ;
[0027] FIG. 6 is a longitudinal side view showing an overlapping margin portion of the positive and negative plates in FIG. 4 in an enlarged manner;
[0028] FIG. 7 is a longitudinal side view showing a medicated sheet of a third embodiment;
[0029] FIG. 8 is a traverse plan view taken along a line VIII-VIII in FIG. 7 ;
[0030] FIG. 9 is a longitudinal side view showing a medicated sheet of a fourth embodiment; and
[0031] FIG. 10 is a traverse plan view taken along a line X-X in FIG. 9 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] Embodiments of the present invention will be described based on the drawings. FIGS. 1 to 3 show a first embodiment. As shown in FIGS. 1 and 2 , the medicated sheet has a positive electrode plate 2 having a large diameter made from a conductive resin, in which carbon black having high normal electrode potential is mixed to thermoplastic resin, and a negative electrode plate 3 having a small diameter made from a conductive resin, in which zinc filler having low normal electrode potential is mixed to thermoplastic resin, arranged to include an overlapping margin portion on a medication surface of a medicated cloth 1 applied with a medicinal agent A containing electrolytic pharmaceutical ingredients that negatively ionize, and the positive electrode plate 2 is arranged to face the skin S. The planar shapes of the medicated cloth 1 and the positive and negative electrode plates 2 , 3 are a square concentric with respect to each other, but the planar shapes may be an arbitrary shape.
[0033] Microscopic pin holder-shaped projections 4 are arranged over the entire surface on a skin contacting surface of the positive electrode plate 2 , and the medicinal agent A is also filled between the pin holder-shaped projections 4 . The pin holder-shaped projection 4 has a height of between 50 and 600 μm, and is formed by injection-molding the conductive resin. In the following drawings starting with FIG. 1 , the height and the interval of the projections 4 are illustrated to be greater than the actual dimension to facilitate the understanding of the projection 4 . Therefore, the electrode plate including the microscopic pin holder-shaped projections 4 can be efficiently and inexpensively manufactured. Furthermore, the medicated sheet can be entirely incinerated as a whole including the positive electrode plate 2 with the pin holder-shaped projections 4 since the positive and negative electrode plates 2 , 3 are made from conductive resin.
[0034] As shown in an enlarged manner in FIG. 3 , a square ring-shaped insulating member 5 a made from resin is attached to the periphery of the overlapping margin portion of the positive and negative electrode plates 2 , 3 so as to insulate the positive and negative electrode plates 2 , 3 , and a separator 6 in which electrolytic solution is impregnated to a non-woven cloth is interposed between the positive and negative electrode plates 2 , 3 of the overlapping margin portion, thereby forming a battery at the overlapping margin portion of the positive and negative electrode plates 2 , 3 . Therefore, as shown with an arrow in FIG. 1 , the current flows through the skin S and the medicinal agent A of the medication surface from the positive electrode plate 2 of high normal electrode potential to the negative electrode plate 3 of low normal electrode potential by the electromotive force of the battery, and the pharmaceutical ingredients that negatively ionize in the medicinal agent A moves from the medication surface towards the skin S in a direction opposite to the flow of the current, and is absorbed into the body from the skin S and the medicinal agent A filled between the pin holder-shaped projections 4 is injected to under the skin.
[0035] FIGS. 4 to 6 show a second embodiment. This medicated sheet has the medicinal agent A containing the electrolytic pharmaceutical ingredients, which positively ionize, applied to the medication surface of the medicated cloth 1 , where the negative electrode plate 3 is overlapped on the skin contacting surface side of the positive electrode plate 2 so that the negative electrode plate 3 contacts the skin S, the microscopic pin holder-shaped projections 4 are arranged on the skin contacting surface of the positive electrode plate 2 excluding the overlapping margin portion with the negative electrode plate 3 , and the medicinal agent A is also filled between the projections 4 , as shown in FIGS. 4 and 5 . Other portions are the same as the first embodiment, and the positive electrode plate 2 is made from a conductive resin mixed with carbon black, and the negative electrode plate 3 is made from a conductive resin mixed with zinc filler. Therefore, this medicated sheet also can be entirely incinerated as a whole since the positive and negative electrode plates 2 , 3 are made from conductive resin.
[0036] As shown in an enlarged manner in FIG. 6 , in the present embodiment as well, the periphery of the overlapping margin portion of the positive and negative electrode plates 2 , 3 is insulated by the square ring-shaped insulating member 5 a , and the separator 6 in which electrolytic solution is impregnated to a non-woven cloth is interposed between the positive and negative electrode plates 2 , 3 , thereby forming a battery at the overlapping margin portion of the positive and negative electrode plates 2 , 3 . Therefore, as shown with an arrow in FIG. 4 , the current flows through the skin S and the medicinal agent A of the medication surface from the positive electrode plate 2 of high normal electrode potential to the negative electrode plate 3 of low normal electrode potential by the electromotive force of the battery, and the pharmaceutical ingredients that positively ionize in the medicinal agent A moves from the medication surface towards the skin S in the direction same as the flow of the current, and is absorbed into the body from the skin S and the medicinal agent A filled between the pin holder-shaped projections 4 is injected to under the skin.
[0037] FIGS. 7 and 8 show a third embodiment. The medicated sheet has the two electrode plates 2 , 3 , one of which becomes positive or negative, made from a conductive resin mixed with carbon black, where the electrode plate 3 having a small diameter is overlapped, so as to include an overlapping margin portion, on the medication surface side of the electrode plate 2 having a large diameter in which the microscopic pin holder-shaped projections 4 are arranged on the skin contacting surface, the electrode plates 2 , 3 are insulated by an insulating member 5 b made from a resin film, lead portion 2 a , 3 a is arranged at each electrode plate 2 , 3 , and the lead portions 2 a , 3 a are exposed to the outer side of the medicated cloth 1 so as to be connected to an external power supply (not shown). Each lead portion 2 a , 3 a may be obtained by wire-connecting a conductive wire, and the like to each electrode plate 2 , 3 . Other portions are the same as the first embodiment, and the pin holder-shaped projections 4 are arranged over the entire skin contacting surface of the electrode plate 2 , and the medicinal agent A is filled between the projections 4 .
[0038] Therefore, in the present embodiment, the positive and negative poles of the two electrode plates 2 , 3 can be arbitrarily changed by connecting the external power supply to the lead portion 2 a , 3 a of each electrode plate 2 , 3 so that the current flows through the skin S and the medicinal agent A of the medication surface from the electrode plate that becomes positive to the electrode plate that becomes negative and response can be made even when the pharmaceutical ingredients positively ionize or negatively ionize, and the voltage between the electrode plates 2 , 3 can be arbitrarily set according to the degree of necessity of treatment. The voltage that fluctuates to a pulse form and the like can also be applied. Furthermore, this medicated sheet can also be entirely incinerated as a whole.
[0039] FIGS. 9 and 10 show a fourth embodiment. This medicated sheet also has the two electrode plates 2 , 3 , one of which becomes positive or negative, made from a conductive resin mixed with carbon black. In the present embodiment, the circular plate-shaped electrode plate 3 having a small diameter is arranged in the same plane on the inner side of the circular ring-shaped electrode plate 2 having a large diameter, the microscopic pin holder-shaped projections 4 are arranged on the skin contacting surface of both electrode plates 2 , 3 , and the medicinal agent A is filled between the projections 4 . The electrode plates 2 , 3 are insulated with an annular insulating member 5 c , and the lead portion 2 a , 3 a to be exposed to the outer side of the medicated cloth 1 is arranged on each electrode plate 2 , 3 . Therefore, this medicated sheet can also arbitrarily change the positive state and the negative state of the two electrode plates 2 , 3 by connecting the external power supply to each lead portion 2 a , 3 a , and can also arbitrarily set the voltage between the electrode plates 2 , 3 . The medicated sheet can also be entirely incinerated as a whole.
[0040] In each embodiment described above, both electrode plates are made from a conductive resin, but the electrode plate not arranged with the pin holder-shaped projection made be made from metal or may be subjected to metal plating.
[0041] In each embodiment described above, the medicinal agent is filled between the pin holder-shaped projections arranged on the skin contacting surface of the electrode plate, but a small hole, a slit, or the like may be formed in the electrode plate including the pin holder-shaped projections, so that the medicinal agent applied or impregnated to the medication surface exudes out to the skin contacting surface side from the small hole, the slit, or the like.
[0042] In each embodiment described above, the pharmaceutical ingredients of the medicinal agent are electrolytic, but the medicated sheet according to the present invention may be applied to that in which the pharmaceutical ingredients are non-electrolytic.
|
An object of the present invention is to safely discard the electrode plate having pin holder-shaped projections of a medicated sheet by incineration. An electrode plate with pin holder-shaped projections is made from a conductive resin in which carbon black serving as a conductive substance is mixed to a thermoplastic resin, so that the electrode plate including the pin holder-shaped projections can be safely discarded by incineration.
| 0
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. Ser. No. 10/002,828 filed with the United States Patent and Trademark Office on Nov. 30, 2001, now U.S. Pat. No. 6,625,947, entitled INSULATED CONCRETE WALL SYSTEM AND METHOD OF MAKING SAME.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a method and system for forming insulated concrete walls. More particularly, though not exclusively, the present invention relates to a method and system for securing insulation panels to a poured concrete basement wall while still providing a visible wall stud that may be used for finishing and other purposes such as hanging drywall.
2. Background of the Invention
Rising utility costs have increased the demand for concrete walls, such as those in most basements, that are insulated. Basement walls made from insulated concrete blocks, with the insulation actually contained in the concrete blocks, are extremely expensive and time consuming to install. Poured concrete walls are much less costly and take less time to install. Insulation has typically then been added or fastened to one or both faces of the concrete. Adding insulation after a concrete wall has hardened is an expensive and time consuming process.
Conventional uninsulated reinforced concrete walls are poured into forms that are typically constructed of heavy plywood panels clamped and nailed into place with cross-ties between parallel panels to prevent them from spreading apart under the hydraulic forces generated by the concrete. The plywood is initially treated so it can be stripped away after the concrete is set.
It has been shown that rigid foam plastic panels are strong enough to substitute for plywood, thus providing an insulated wall. For example, in U.S. Pat. No. 6,240,692 issued Jun. 5, 2001 to Yost, a series of rigid foam panels are used in place of the plywood forms. The foam panels of Yost are left in place permanently, thus providing the poured concrete wall with insulation on both sides. Yost also discloses a plurality of wall studs encased in each panel, each stud having a trust structure for increased strength.
Similarly, a pair of insulative panels are used in place of the plywood forms in U.S. Pat. No. 5,040,344 issued Aug. 20, 1991 to Durand. Durand discloses reinforcing each of the panels with horizontal stiffeners and using removable shores to maintain the panels in a vertical position during concrete pouring.
All of these systems require specialty components that are time consuming to install and drastically increase the costs of insulating poured concrete walls. Further, many of these systems also have their studs embedded in the foam. Embedding the studs in the foam requires the foam be specially made to fit the studs. This prevents the builder of the concrete wall from selecting the thickness of insulation to be used on site. This also makes it difficult to find the studs if additional finishing of the walls is to be done. There is therefore a need for an insulation system that is quick and easy to install, variable, relatively inexpensive, and that has wall studs visible beyond the insulation panels.
Because many of these insulation systems also use foam panels in place of plywood or aluminum forms, the insulation panels must be on both sides of the concrete wall. Often, insulation is only desired on the inside portion of the concrete walls. There is therefore a need for an insulation system that may be used only where and when desired.
It is therefore a primary feature of the present invention to overcome the problems in the prior art.
It is a further feature of the present invention to provide an insulated concrete wall system that is relatively low cost and easy to use.
Another feature of the present invention is to provide an insulated concrete wall system that allows insulation panels to be placed on one or both sides of a poured concrete wall.
A still further feature of the present invention is the provision of an insulated concrete wall system in which wall studs are secured in the poured concrete wall upon hardening of the concrete.
Another feature of the present invention is the provision of an insulated concrete wall system in which the wall studs are visible for easy finishing of the wall.
A further feature of the present invention is the provision of an insulated concrete wall system in which any size of foam insulation or fiberglass hardboard insulation may be used without the need for special grooves to be cut in the insulation material.
A still further feature of the present invention is the provision of an insulated concrete wall system in which the wall studs retain the foam panels to prevent them from floating during concrete pouring.
These, as well as other features, objects, and advantages of the present invention, will become apparent from the following specification and claims.
BRIEF SUMMARY OF THE INVENTION
The present invention generally comprises an insulated concrete wall system and method for installing same. The system of the present invention includes insulation panels, walls studs and forms placed so as to form a channel into which concrete will be poured. Insulation panels and forms are well known in the art and commercially available. The channel's thickness is designed to correspond to the desired thickness of the wall.
The generally T-shaped wall studs are placed adjacent to one end of an insulation panel before the next insulation panel is put in place. The front section of the T-shaped wall stud extends beyond the front surface of the insulation panels and will be visible on the completed wall. The anchor section of the T-shaped wall studs extends beyond the width of the insulation panels and into the channel itself.
The thickness of the channel is maintained by the use of cross-ties. Preferably, these cross-ties go through slots in the T-shaped wall studs. The wall studs also preferably include several retaining nubs which prevent the insulation panels from floating or otherwise moving during concrete pouring. At the corner of a wall, a corner bracket may be used to secure two insulation panels in proper position. The corner bracket includes two channels for receiving insulation panels. The ends of these channels may include a retaining portion to secure the insulation panels in place.
When concrete is poured to fill the channel, the concrete surrounds the anchor section of the T-shaped wall stud. Upon hardening, the concrete secures the T-shaped wall stud in place. Aluminum or wooden forms are used to support the insulation panels and T-shaped wall studs during concrete pouring and are removed after the concrete has hardened.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the insulated concrete wall system of the present invention as assembled.
FIG. 2 is a top view of one embodiment of the insulated concrete wall system of the present invention.
FIG. 3 is one example of the T-shaped wall stud of the present invention.
FIG. 4 is a second example of the T-shaped wall stud of the present invention.
FIG. 5 is a top view of the corner bracket, as installed, of the present invention.
FIG. 6 is a side view of the embodiment of the T-shaped wall stud shown in FIG. 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will be described as it applies to its preferred embodiment. It is not intended that the present invention be limited to the described embodiment. It is intended that the invention cover all modifications and alternatives which may be included within the spirit and scope of the invention.
Now, referring to the drawings, FIG. 1 illustrates the insulated concrete wall system 10 of the present invention. The insulated concrete wall system 10 generally includes a number of forms 12 and insulation panels 14 secured to the concrete wall by a plurality of wall studs 16 . The forms are well known in the art and made of wood, aluminum or other suitable materials.
Initially, insulation panels 14 , are placed upright along the edge of what is to be the concrete wall 22 . Each insulation panel or sheet of insulation material has a front surface, rear surface, top side, bottom side, first edge, and second edge. A T-shaped wall stud 16 is placed along either the first or second edge of the insulation panel 14 . Next, another insulation panel 14 is placed on the other side of the T-shaped wall studs 16 . This process is continued until one side of the wall is formed.
As is also shown in FIG. 1 , the builder places forms 12 across from the sheets of insulation 14 to form a channel 20 into which concrete 22 is poured. The width of the channel 20 is designed to correspond to the desired width of the concrete wall 22 . Typically, building codes require concrete walls to be at least 8 inches thick. Additional forms 12 may be placed on the outside of the insulation panels 14 and wall stud 16 to provide support necessary to prevent the insulation panels 14 and wall studs 16 from moving when concrete 22 is poured.
When needed, corner brackets 18 may be used to secure two insulation panels 14 at right angles to one another. As is more clearly shown in FIG. 5 , the corner bracket 18 includes a first channel 36 and a second channel 38 into which insulation panels 14 may be secured. Preferably, the corner bracket 18 may also include a retaining portion 40 to keep the insulation panels 14 in place.
As is shown in FIG. 3 , the T-shaped wall studs 16 of the present invention generally include a front section 26 that is connected to an anchoring section 28 . The retaining portion 30 at the end of the anchor section 28 is also included. The retaining section 30 prevents the T-shaped wall stud 16 from being easily removed from the concrete wall 22 . Preferably, the T-shaped wall stud 16 is made by extruding a resilient plastic material. This helps to keep costs down and allows the wall stud 16 to be made to any desired length. A plurality of holes 42 can be added to allow the user to insert a variety of securing devices 46 such as nails, pins, etc.
Alternatively, the wall stud 16 may also include ribs 34 and slots 32 as is shown in FIG. 4 . The slots 32 are designed to accommodate the cross-ties 24 that may be inserted through the T-shaped wall studs 16 during installation as is shown in FIG. 1 . Preferably, the slots 32 are spaced vertically along one side of the front section 26 . The number and spacing of the slots 32 can vary depending on the user's preference. For example, as shown, the slots 32 can be of varying lengths to accommodate the variety of cross-tie patterns used by contractors. For example, a contractor may use a plurality of 4 inch long slots in a predetermined pattern to accommodate both an 8×8 pattern of cross-ties 24 a 6×12 pattern. Either way, the slots 32 are thereby designed to accommodate the cross-ties 24 without the need to create a customized piece. Moreover, because the slots 32 can accommodate both typical patterns, there is no need to have large holes or gaps in the wall stud's face. This allows a user to secure nails, screws or other securing items during drywalling, finishing or at any other time. Using cross-ties 24 ensures the concrete wall 22 will be of uniform thickness. It is preferred that the cross-ties 24 be of the break-away variety.
The ribs 34 provide a securing and stabilizing function. In use, the ribs 34 help to keep the insulation panels 14 in place. Additionally, the ribs 34 stabilize the wall by providing a channel along which water can flow. When the wall stud 16 of the present invention is used and the concrete 22 has hardened, it will eventually develop minute cracks. These cracks are most likely to develop along the weakest portions of the wall. The concrete 22 is at its thinnest where the wall stud 16 is located. Thereby, the cracking can be controlled allowing for thermal expansion. When a small crack does develop, water may seep in. If the water has no place to go, it could seep into the insulation, causing mold, warping and spots on any finished walls. However, the ribs 34 create vertical channels traveling the length of the wall stud 16 . These channels allow any incoming water to flow down below grade to the footing where it can be allowed to drain into sump pumps, tile, etc.
Also shown in FIG. 2 , strips 44 of bentonite may be added as desired. Typically, the strips 44 of bentonite have a sticky backing, allowing for easy installation. Bentonite increases the walls ability to manage any incoming water. As is shown in FIGS. 2 and 6 , the wall stud 16 may also include nubs 35 which are designed to prevent the insulation panels 14 from upward movement when the concrete 22 is poured into the gap 20 . Preferably, the nubs 35 are located on the anchor section 28 . The nubs 35 may be of any desired shape and be located on either or both the front section 26 or the anchor section 28 of the wall stud 16 .
As can also be seen in FIG. 2 , a portion of the anchor section 28 of the wall stud 16 is secured within the concrete 22 of the wall. The desired width of the insulation panels 14 may be changed by the builder at any time. The anchor section 28 of the wall stud 16 is of a length that allows for many different thicknesses of insulation panels 14 to be used. For example, if four inches of insulation is used instead of two inches, two inches less of the anchoring section 28 will be secured in the concrete 22 of the wall. In order to secure the insulation panels 14 in place, a pin, nail or other securement device 46 can be used. A plurality of holes 42 are preferably provided in the anchor section 28 of the wall stud 16 . Preferably, the holes 42 can be staggered to provide a hole 42 for the different thicknesses of insulation panels 14 that are commonly in use. In this manner, the present invention can be used with 1, 2, 3, or 4 inch varieties of foam insulation. An additional benefit in the holes is realized when the concrete 22 is poured. Any holes 42 that are not used are filled by concrete 22 . This further secures the wall stud 16 within the concrete 22 .
Rebar is typically required and must be added to the interior of the concrete wall. Supporting the rebar during the pouring process may be accomplished through the use of plastic supports 48 . Each plastic support 48 includes a vertical portion that rests against the insulation panels 14 . The horizontal portion begins at the corner. The corner is placed around a hole 42 through which a nail or pin 46 is placed. The staggered holes 42 allow the rebar to be placed at desired horizontal locations. Additional supports 48 may be used to place rebar as need to meet any horizontal spacing. The horizontal spacing of rebar may be dictated by code, city or governmental regulations or an engineer's/owner's requirements. The curved or receptively shaped end portion of the plastic support 48 is shaped to accommodate a typical piece of rebar. Thus, rebar can be positioned during assembly of the wall form.
Once all of the insulation panels 14 , wall studs 16 , forms 12 and other materials are in proper position, concrete 22 is poured into the gap 20 . After the concrete 22 has hardened or set, the forms 12 are removed. This leaves an insulated concrete wall wherein the wall studs 16 are clearly visible. Additionally, because the wall studs 16 are on the outside of the insulation panels 14 , drywall may be easily secured to the wall studs 16 . Therefore, finishing a wall insulated according to the system of the present invention is expedited. Further, because the wall studs 16 are on the outside of the insulation panels 14 , a small gap will exist between any installed drywall and the insulation panels 14 . This increases the R-value of the wall constructed according to the system 10 of the present invention. Higher R-values are desirable as homes constructed with high R-value walls have lower overall heating and cooling costs.
Further, because the wall studs 16 are on the outside of the insulation panels 14 , no special connection between the insulation panels 14 and wall studs 16 is required. This allows the builder to purchase any type of insulation panel 14 from any vendor at the lowest possible costs.
A general description of the present invention as well as a preferred embodiment to the present invention has been set forth above. Those skilled in the art to which the present invention pertains will recognize and be able to practice additional variations in the methods and systems described which fall within the teachings of this invention. Accordingly, all such modifications and additions are deemed to be within the scope of the invention which is to be limited only by the claims appended hereto.
|
A method and system for installing an insulated concrete wall includes insulation panels placed in an upright manner. Generally T-shaped wall studs are placed next to the insulation panels such that the front section of the wall stud is on the outside of the insulation panels and an anchoring section of the wall stud extends beyond the insulation panels into the gap into which concrete will later be poured. Concrete pouring forms are placed so as to render the gap into which concrete will be poured a desired thickness. The wall stud may also include slots for receiving cross-ties that secure the concrete pouring forms in proper position and retaining nubs that prevent the insulation panels from floating when concrete is poured. Concrete is then poured into the gap, surrounding the anchoring section the T-shaped wall stud.
| 4
|
FIELD OF THE INVENTION
The present invention concerns the sector of socks, and specifically, it pertains to socks with different knitted parts due to yarn and elasticity for a therapeutic use.
BACKGROUND OF THE INVENTION
Currently, socks are known, which have knitted parts that are different from area to area. However, such socks are used mostly in sports activities. The different parts of the socks are made depending on the sports activity to which the socks are intended and essentially perform the tasks of muscle support, ventilation, and stabilization of specific parts of the foot that are most affected and/or stressed.
SUMMARY AND OBJECTS OF THE INVENTION
On the other hand, the object of the present invention is to provide socks for a health use in the presence, and as an adjuvant in the therapy, of certain diseases, such as arterial insufficiency, cardiac decompensation and circulatory decompensation; venous insufficiency; arthrosis and rheumatism.
Such an object is accomplished by designing the socks so that, besides the maximum wearability, they also perform a mechanical action on the feet, ankles, and legs of the person in response to the movements of the lower limbs, in order to stimulate blood circulation, to compress specific areas as well as to prevent and reduce the feeling of fatigue and swelling of the legs, etc.
Thus, for example, in the presence of arterial insufficiency, and cardiac or circulatory decompensation, the socks act as a pump on the foot and the neck of the foot by stimulating the arterial blood flow; in the presence of venous insufficiency, the socks will build up a diffuse and graduated compression on the entire leg with ascending thrusts to aid venous downflow; for arthrosis and rheumatism, the socks are expected to perform a strong compression and support action at the level of the joints.
The above-mentioned object is accomplished with a sock for therapeutic use comprising a leg portion, a foot portion and an ankle-neck of the foot portion, where at least some of these portions have an elasticized knitted structure with graduated elasticity in order to perform a specific action on the lower limbs of a person.
Greater details of the present invention will become more evident from the description given below with reference to some examples of socks illustrated in the drawings.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a side view showing a first example of a partially elasticized sock;
FIGS. 2, 3 and 4 are views similar to FIG. 1 showing the embodiment variants of the sock of FIG. 1;
FIG. 5 is a view similar to FIG. 1 showing a second example of a completely elasticized sock; and
FIGS. 6, 7 and 8 are views similar to FIG. 1 showing the embodiment variants of the sock of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings in particular, a sock according to the invention generally comprises an edge or cuff 11, a leg 12, a heel 13, a part 14 that adapts to the neck of the foot, a part 15 that covers the dorsal aspect of the foot, a sole 16 for the plantar aspect of the foot, and a toe area 17.
The sock is made on a circular stocking knitting machine using prior-art knitting methods available to persons skilled in the art but with an appropriate selection of the yarns and of the type of knitting with which the various parts of the sock are made.
In one embodiment, the sock according to the present invention is made by using at least one basic yarn made of cotton, wool, synthetic, or the like, for the entire sock and one elastic yarn 18, together with the basic yarn, at least in the dorsal area 15 and in the area of the neck of the foot 14 and on a part 12' of the leg 12, at the level of the ankle (see FIG. 1).
The parts of the leg and of the foot, except for the cuff 11, may all be made of smooth jersey as in FIG. 1 or may all be made of terry cloth jersey as in FIG. 2. As an alternative, the foot may have at least the sole 16 made of terry cloth jersey, as shown in FIG. 3. Some parts of the sock may also have reinforcements 19, as shown in FIG. 4, obtained from double terry cloth jersey with the insertion of additional yarns or yarns of varying size, etc.
In the elasticized parts (12', 14, 15) that are obtained with the presence of elastic yarn, the elasticity may be graduated, depending on the therapeutic action that the sock must perform, by varying the percentage of elastomer in the jersey or its size, which will be, e.g., higher in the area of the foot and the ankle and lower in the part 12' of the leg.
The arrows in FIGS. 1 and 4 indicate the "pumping" action of the sock, which tends to aid the circulation of the blood with a venous downflow.
In another embodiment (cf. FIGS. 5, 8) the sock of the present invention is made by using at least one basic yarn made of cotton, wool, synthetic, or the like together with an elastic yarn 20 for the entire sock. Knitted toes of any type may be chosen. Here also, the parts of the foot, the neck of the foot, and the leg may all be made of smooth jersey (cf. FIG. 5), or they may all be made of terry cloth jersey (cf. FIG. 6). As an alternative, the foot may have at least the sole 16 made of terry cloth jersey as shown in FIG. 7. Some parts of the sock may also have reinforced areas 21, as shown in FIG. 8, obtained with a double terry cloth jersey or with additional yarns or yarns of varying size.
This sock, besides by the elastic yarn in all its parts, is characterized in that it has a tighter knit, obtained, i.e., with greater pressure, at least in a part of the foot 15 and of the sole 16, of the neck of the foot 14 and of the leg, especially at the ankle.
Thus, the sock has an elastic structure that is varied from part to part. The knit at the leg 12 and in the toe area 17 of the foot, though elastic, shall be suitable for ventilation, e.g., 1:1 at seams. In the foot/ankle parts, it shall be at the largest seams in order to increase the pressure on the limb and to act as a pump to stimulate the blood circulation.
Moreover, the elasticity may be graduated by using, in the various parts of the sock, yarns having a varying percentage of elastomer varying a knotting of knit curls or yarns of varying denier, therefore maintaining a higher elasticity in the foot/ankle areas and a lower elasticity in the leg.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
|
A sock for therapeutic use in arterial insufficiency, cardiac and circulatory decompensation, venous insufficiency, arthrosis and rheumatism. The sock includes a leg portion (12), a foot portion (15, 16) and an ankle-neck of the foot portion (12', 14) between the foot and the leg, where at least some of the said portions of the sock have an elasticized knit structure with an elasticity graduated from part to part.
| 3
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a multi-band antenna for tablet computers, especially to a multi-band antenna for tablet computers that covers the GSM850/900/1800/1900/UMTS and LTE700/2300/2700 operations. The multi-band antenna has higher practical value and more applications.
2. Description of Related Art
Along with fast progress in information and communication technologies, people have more requirements for wireless communication technology, not only the quality but also the speed. There are various systems for electronics with communication receivers. The antenna systems of the electronics are not compatible due to different system operation frequencies.
Refer to Taiwanese Pat. App. Pub. No. 201123617 published on Jul. 1, 2011, a multi-band antenna is revealed. The multi-band antenna includes an antenna body, a flat substrate, a grounding part and a feed point. The multi-band antenna is a three-dimensional structure having a bottom surface, a rear surface, a top surface and an outer surface. The above four surfaces are respectively disposed with the antenna body. The flat substrate and the grounding part are arranged at the bottom surface of the multi-band antenna. The flat substrate is located on a gap between the grounding part and the antenna body on the bottom surface of the multi-band antenna. The antenna body, the flat substrate and the grounding part are connected at the feed point.
Refer to Taiwanese Pat. App. Pub. No. 201021292 published on Jun. 1, 2010, a multi-band antenna is revealed. The multi-band antenna includes a loop microstrip line and a parasitic microstrip line. The loop microstrip line consists of a signal feed end and a first grounding end. The length of a path between the signal feed end and the first grounding end is a half wavelength. A signal is input through the signal feed end to excite a first resonant mode frequency from the loop microstrip line. The parasitic microstrip line is composed of a second grounding end and a first open end. The length of a path between the first open end and the second grounding end is one-fourth wavelength. The loop microstrip line is arranged around the parasitic microstrip line. Electromagnetic radiation with the first resonant mode frequency is coupled to the parasitic microstrip line so that the parasitic microstrip line is excited to have a second resonant mode frequency. The second resonant mode frequency is different from the first resonant mode frequency.
However, although the antennas mentioned above perform the expected functions while being applied to multiple system band frequencies, they still have certain limitations. In practice, LTE (Long Term Evolution), a next-generation wireless broadband technology, has been developed. Compared with GSM, the LTE provides higher data speed and a lot better quality. LTE standard can be used with many different frequency bands including 700, 2300, 2500 MHz. Yet GSM-850/900/1800/1900 MHz and UTMS bands are still in use. The above antennas are unable to be used for a broad range of frequencies including LTE700/2300/2500, GSM 850/900/1800/1900, UMTS, etc and there is room for improvement.
SUMMARY OF THE INVENTION
Therefore it is a primary object of the present invention to provide a multi-band antenna for tablet computers that covers the GSM850/900/1800/1900/UMTS and LTE700/2300/2700 operations.
In order to achieve the above object, a multi-band antenna for tablet computers of the present invention includes a first path, a second path, a third path, a fourth path, a fifth path, a sixth path, a seventh path, an eighth path and a grounding portion. The first path includes a bent part arranged at a first end thereof. Two ends of the second path are respectively extended to form a bent part and an extension part while the bent part is connected to a second end of the first path. The third path consists of a first bent part at a first end thereof and a second bent part at a second end thereof. A middle part of the third path is connected to the extension part of the second path. The first end of the fourth path is connected to the second path. The fifth path is connected to a second end of the fourth path. Two ends of the fifth path are respectively extended to form a first extension part and a second extension part corresponding and parallel to each other. Two ends of the sixth path are respectively a first bent part and a second bent part. The first bent part of the sixth path is connected to the first extension part of the fifth path. The seventh path is connected to the second bent part of the sixth path. Two ends of the eighth path are formed a first bent part and a second bent part respectively. The first bent part of the eighth path is connected to the second extension part of the fifth path. The grounding portion is connected to the second bent part of the third path and the second bent part of the eighth path. Thereby the multi-band antenna is used for multi-band operations including the GSM850/900/1800/1900/UMTS and LTE700/2300/2700, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein
FIG. 1 is a schematic drawing showing a structure of an embodiment according to the present invention;
FIG. 2 shows return loss plotted against frequency for an embodiment with a chip inductor or without a chip inductor according to the present invention;
FIG. 3 is a graph of impedance versus frequency plot for an embodiment with a chip inductor or without a chip inductor according to the present invention;
FIG. 4 is a plot of return loss versus frequency for an embodiment with a 15 nH chip inductor, with an 18 nH chip inductor, and with a 22 nH chip inductor according to the present invention;
FIG. 5 is a plot of impedance versus frequency for an embodiment with a 15 nH chip inductor, with an 18 nH chip inductor, and with a 22 nH chip inductor according to the present invention;
FIG. 6 is a schematic drawing showing a structure of an embodiment with a modified first path according to the present invention;
FIG. 7 is a plot of return loss versus frequency for an embodiment with a modified first path according to the present invention;
FIG. 8 is a graph of impedance versus frequency plot for an embodiment with a modified first path according to the present invention;
FIG. 9 is a schematic drawing showing a structure of an embodiment with a modified third path according to the present invention;
FIG. 10 is a plot of return loss versus frequency for an embodiment with a modified third path according to the present invention;
FIG. 11 is a graph of impedance versus frequency plot for an embodiment with a modified third path according to the present invention;
FIG. 12 is a plot of return loss versus frequency for a first bent part of a modified third path according to the present invention;
FIG. 13 is a graph of impedance versus frequency plot for a first bent part of a modified third path according to the present invention;
FIG. 14 is another graph of impedance versus frequency plot for a first bent part of a modified third path according to the present invention;
FIG. 15 is a schematic drawing showing a structure of an embodiment with a modified fourth path according to the present invention;
FIG. 16 is a plot of return loss versus frequency for an embodiment with a modified fourth path according to the present invention;
FIG. 17 is a graph of impedance versus frequency plot for an embodiment with a modified fourth path according to the present invention;
FIG. 18 is a schematic drawing showing a structure of an embodiment with a modified fifth path according to the present invention;
FIG. 19 is a plot of return loss versus frequency for an embodiment with a modified fifth path according to the present invention;
FIG. 20 is a graph of impedance versus frequency plot for an embodiment with a modified fifth path according to the present invention;
FIG. 21 is a schematic drawing showing a structure of an embodiment with a modified seventh path according to the present invention;
FIG. 22 is a plot of return loss versus frequency for an embodiment with a modified seventh path according to the present invention;
FIG. 23 is a graph of impedance versus frequency plot for an embodiment with a modified seventh path according to the present invention;
FIG. 24 is a schematic drawing showing a structure of an embodiment with a modified fifth path, a modified sixth path, a modified seventh path and a modified eighth path according to the present invention;
FIG. 25 is a plot of return loss versus frequency for an embodiment with a modified fifth path, a modified sixth path, a modified seventh path and a modified eighth path according to the present invention;
FIG. 26 is a graph of impedance versus frequency plot for an embodiment with a modified fifth path, a modified sixth path, a modified seventh path and a modified eighth path according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Refer to FIG. 1 , an antenna 1 of the present invention includes a first path 11 , a second path 12 , a third path 13 , a fourth path 14 , a fifth path 15 , a sixth path 16 , a seventh path 17 , an eighth path 18 and a grounding portion 19 . The first path 11 includes a bent part 111 arranged at a first end thereof. A chip inductor 112 is disposed on the first path 11 .
Two ends of the second path 12 are extended to form a bent part 121 and an extension part 122 respectively while the bent part 121 is connected to a second end of the first path 11 .
A first end of the third path 13 is a first bent part 131 while a second end of the third path 13 is a second bent part 132 . A middle part of the third path 13 is connected to the extension part 122 of the second path 12 .
As to the fourth path 14 , its first end is connected to the second path 12 .
The fifth path 15 is connected to a second end of the fourth path 14 . Two ends of the fifth path 15 are extended to form a first extension part 151 and a second extension part 152 respectively. The first extension part 151 and the second extension part 152 are corresponding and parallel to each other.
Two ends of the sixth path 16 are respectively a first bent part 161 and a second bent part 162 while the first bent part 161 is connected to the first extension part 151 of the fifth path 15 .
The seventh path 17 is connected to the second bent part 162 of the sixth path 16 .
The eighth path 18 includes a first bent part 181 and a second bent part 182 respectively formed on two ends thereof The first bent part 181 is connected to the second extension part 152 of the fifth path 15 .
The grounding portion 19 is connected to the second bent part 132 of the third path 13 and the second bent part 182 of the eighth path 18 .
Refer to FIG. 2 , it shows return loss plotted against frequency for an embodiment with a chip inductor or without a chip inductor of the present invention. Without the chip inductor, an imaginary part of a mode at low frequency 0.74 GHz/0.96 GHz is much lower/larger. By means of a direct-fed monopole and the chip inductor, a current at a feed end is dispersed so that current near the feed point becomes smaller. Thus the coupling of the feed end and the coupled monopole is getting smaller and the amplitude of a real part at the low frequency 0.74 GHz/0.96 GHz is getting smaller. Also refer to FIG. 3 , a graph of impedance versus frequency plot for an embodiment with a chip inductor or without a chip inductor according to the present invention is disclosed. Without the disposition of the chip inductor, the mode has quite large amplitude of the impedance at 1.54 GHz of the mode. After adding the chip inductor, the mode shifts to low frequency 1.2 GHz and the amplitude of the real part as well as the amplitude of the imaginary part is getting larger. Thus the lower imaginary part of the two modes at low frequency is pulled up by this way. Therefore a wider bandwidth is obtained by mode-matching.
Refer to FIG. 4 and FIG. 5 , a plot of return loss versus frequency and a plot of impedance versus frequency for an embodiment with a 15 nH chip inductor, with an 18 nH chip inductor, and with a 22 nH chip inductor according to the present invention are revealed. When the chip inductor is changed into 15 nH, the amplitude of the two modes at the low frequency is significantly increased. This results in a poorer matching at the low frequency because that a shunt current from the feeding end to the monopole is reduced and the coupling of the feed end and the coupled monopole antenna element is increased when the inductance is reduced. On the other hand, when the chip inductor is changed into 22 nH, the shunt current to the monopole is increased and the coupling is reduced. This causes small impedance. Thus the 18 nH chip inductor is an optimal option.
Refer to FIG. 6 , a schematic drawing showing a structure of an embodiment with a modified first path 11 is revealed. Also refer to FIG. 7 and FIG. 8 , a plot of return loss versus frequency and a plot of impedance versus frequency for the embodiment with a modified first path 11 are disclosed. The first path 11 of the antenna 1 is getting shortened. With reference of the figures, it is learned that the mode at the low frequency of 0.96 GHz is shifted toward the low frequency. This is due to that the unipolar current density is increased when the first path 11 is shortened. And the unipolar inductance from the grounding portion 19 is increasing. Thus the second mode is moved toward the low frequency.
Refer to FIG. 9 , a schematic drawing showing a structure of an embodiment with a modified third path is revealed. The third path 13 of the antenna 1 is gradually shortened. Also refer to FIG. 10 and FIG. 11 , it is learned that although the third path 13 is an excitation path of 0.96 GHz mode, the changing of the length of the rear end thereof has little influence on the low frequency mode of 0.96 GHz. This is because that the current distribution of this mode at the rear end is quite small so that only matching changes. Take a look at the high frequency mode of 2. 7 GHz, it continues to shift to the high frequency. An increase of the path length at the rear end is for shifting the third harmonic frequency of the third path 13 to low frequency so that the mode can be applied to LTE-2500 band. Moreover, refer to FIG. 12 , FIG. 13 and FIG. 14 , a plot of return loss versus frequency and graphs of impedance versus frequency for an embodiment with a modified first bent part of a third path are revealed. After the first bent part 131 of the third path 13 being removed, the third path is still shortened from the left side to the right side. It is obvious that the mode is gradually shifted to the high frequency. And it is quite clear that this path is the excited 0.96 GHz mode.
Refer to FIG. 15 , a schematic drawing showing a structure of an embodiment with a modified fourth path is revealed. Refer to FIG. 16 and FIG. 17 , when the fourth path 14 of the antenna 1 is removed, a real part and an imaginary part of the mode at 1.75 GHz are both lower. After addition of the fourth path 14 , both the real part and the imaginary part are increased. A central point of the amplitude of the imaginary part is moved toward the zero level so that the imaginary part is getting closer to zero. Thus the total bandwidth is increased. Moreover, when the fourth path 14 is deleted, the total impedance of the mode at the high frequency and at the intermediate frequency is too low. The reduction of the total impedance is due to that the coupling of the direct-fed monopole and the coupled monopole is reduced when the fourth path 14 is deleted. A new mode value is generated at 2.06 GHz. This mode value is excited by a seven-fourths wavelength of 0.73 GHz and the current is concentrated on a path of the coupled monopole, with a presence of a pole of 40.4. Thus the fourth path 14 not only has great effect on impedance matching at high and the intermediate frequency but also inhibits the seven-fourths wavelength of 0.73 GHz.
Refer to FIG. 18 , a schematic drawing showing a structure of an embodiment with a modified fifth path is revealed. As shown in the figure, the fifth path 15 of the antenna 1 is used to replace the chip inductor 112 . The addition of the chip inductor 112 results in decreasing gain and lower efficiency. In order to prevent this from happening, the chip inductor 112 is replaced by the inductance generated by metal wires of the antenna 1 . Use thin wires and increase the length of the fifth path 15 to increase the inductance. Refer to FIG. 19 and FIG. 20 , when the length of the fifth path 15 is gradually shortened, it is obvious matching and modes disappear gradually at high-frequency and intermediate-frequency while the low-frequency that part has only small variations. Therefore the fifth path 15 has only a bit low-frequency shift while matching occurs at high and intermediate frequency and higher-order-modes of this mode shift toward low frequency.
Refer to FIG. 21 , a schematic drawing showing a structure of an embodiment with a modified seventh path is revealed. When the length of the rear end of the seventh path 17 is changed, there is only minimal or no apparent effect on the low frequency, as shown in FIG. 22 and FIG. 23 . It is learned that the current at the rear end of the coupled monopole on the right side is quite small. Thus the rear end only has impedance matching at the low frequency while there is an obvious trend toward high frequency of high-and-intermediate frequency higher-order-modes. It is proved that this mode is a higher-order-mode of 0.74 GHz.
Refer to FIG. 24 , a schematic drawing showing a structure of an embodiment with a modified fifth path, a modified sixth path, a modified seventh path, and a modified eighth path is disclosed. In order to understand the modes excited by the fifth path 15 , the sixth path 16 , the seventh path 17 , and the eighth path 18 more clearly, the fifth path 15 , the sixth path 16 , the seventh path 17 , and the eighth path 18 are all removed. Refer to FIG. 25 and FIG. 26 , it is learned that the mode with lowest frequency of 0.74 GHz, 1.51 GHz, 1.75 GHz, and 2.35 GHz all disappear. Thus the lowest frequency of the fifth path 15 , the sixth path 16 , the seventh path 17 , and the eighth path 18 is a quarter wavelength at the base frequency while the rest are higher-order-modes of the mode.
In summary, compared with the structure available now, the present invention can cover the LTE700/2300/2700 and GSM850/900/1800/1900/UMTS operations and has higher practical value.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalent.
|
A multi-band antenna for tablet computers is revealed. The antenna includes a first path, a second path, a third path, a fourth path, a fifth path, a sixth path, a seventh path, an eighth path and a grounding portion, connected to one another. Thereby the antenna can cover the GSM 850/900/1800/1900/ UMTS and LTE 700/2300/2700 operations.
| 7
|
[0001] The present Application claims priority to U.S. Provisional Application Serial No. 60/360,446 filed Feb. 28, 2002, herein incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to child-seat liners. Specifically, the present invention provides protective articles comprising child-seat liners, systems comprising child-seat liners, methods for using child-seat liners (e.g. with a shopping cart), and methods for making child-seat liners. The present invention also provides child-seat liner cut-pieces and patterns.
BACKGROUND OF THE INVENTION
[0003] Shopping cart child seats/baskets and shopping cart handles tend to be unclean and dangerous for children. Many types of bacteria, mold, and yeast have been found on shopping cart baskets and handles, including Coliform, E. coli , and staphylococcus. Dust, dirt, soil and fecal matter has also been found on shopping cart handles and baskets. Furthermore, the national SAFE KIDS campaign has reported dramatic statistics regarding the dangers of shopping carts for children, such as the fact that at least five children since 1985 have died as a result of shopping cart accidents. Also, in 1998, nearly 25,600 children were treated for shopping cart injuries, with eighty-three percent of the injuries accounted for by children under four years old (according to the national SAFE KIDS campaign).
[0004] Many parents use child-seat liners positioned in the shopping cart basket of a shopping cart in an attempt to protect their child and make their child more comfortable while sitting in the shopping cart basket during a shopping trip. While many child-seat liners are known, many of these are hard to use, don't satisfactorily protect the child, or may fall out of the shopping cart basket. What is needed is a child-seat liner that is easy to secure to the child seat and that protects the child from contact with unclean shopping cart handles and baskets.
SUMMARY OF THE INVENTION
[0005] The present invention provides protective articles comprising child-seat liners, systems comprising child-seat liners, methods for using child-seat liners (e.g. with a shopping cart, high-chair, or other child-seat with safety straps), and methods for making child-seat liners. The present invention also provides child-seat liner cut-pieces and patterns.
[0006] In some embodiments, the present invention provides articles (e.g. child protecting articles) comprising a child-seat liner, wherein the child-seat liner comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a flap, and wherein the flap is moveable between a closed position and an open position, wherein the open position forms a safety strap opening in the back panel. In particular embodiments, the bottom panel is cushioned (e.g. such that a child may sit on it comfortably). In other embodiments, the back panel is cushioned (e.g. such that a child may lean their back against it comfortably). In particular embodiments, the back and/or bottom panel comprise two layers of fabric with a fiberfill type material between the layers of fabric.
[0007] In particular embodiments, the panels (e.g. back, bottom, front, and sides) comprise fabrics that comprise cotton, nylon, polyester, polycotton, wool, linen, flax, jute, rayon, acrylic fiber, calico, muslin, canvas, silk, or combinations thereof. In certain embodiments, the panels comprise leather, vinyl, plastic, corduroy, denim, twill, polyester, cotton, or other material. In some embodiments, the panels comprise an anti-bacterial compound.
[0008] In certain embodiments, the child-seat liner further comprises a front panel connected to (e.g. integral with or sewn to) the bottom panel. In other embodiments, the front panel further comprises at least one front opening. In particular embodiments, the front opening is configured for one leg or two legs of a child sitting in the child-seat liner. In preferred embodiments, the front panel further comprises two front openings. In some embodiments, the front opening or front openings have binding around their edge.
[0009] In some embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel. In other embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to (e.g. integral with or sewn to) the bottom panel, the back panel, and the front panel. In preferred embodiments, the child-seat liner does not contain attached safety straps.
[0010] In certain embodiments, the back panel is configured to substantially cover a shopping cart basket back wall (e.g. the back panel covers at least 85%, preferably 95%, or more preferably 99-100% of the back wall). In other embodiments, the bottom panel is configured to substantially cover a shopping cart basket bottom (e.g. the bottom panel covers at least 85%, preferably 95%, or more preferably 99-100% of the bottom). In some embodiments, the front panel is configured to substantially cover a shopping cart basket front wall (e.g. the front panel covers at least 85%, preferably 95%, or more preferably 99-100% of the front wall). In other embodiments, each of the side panels is configured to substantially cover a shopping cart basket side wall (e.g. each of the side panels covers at least 85%, preferably 95%, or more preferably 99-100% of the side walls).
[0011] In particular embodiments, the flap has a shape selected from a rectangle, a square, a circle, a half circle, a trapezoid, octagon, a triangle, or a shape similar to one of these shapes. In certain embodiments, the flap has a surface area of at least four square inches or at least five, six, seven, eight, nine, ten, eleven, twelve, fifteen, twenty, twenty-five, thirty, forty, fifty, or at least sixty square inches. In other embodiments, the safety strap opening has a size that is at least five square inches, at least six, seven, eight, nine, ten, eleven, twelve, fifteen, twenty, twenty-five, thirty, forty, fifty, or sixty square inches. In some embodiments, the surface area of the flap is approximately the same size as the safety strap opening. In preferred embodiments, the safety strap opening is configured to allow both a first safety strap and a second safety strap to pass through the safety strap opening. In other preferred embodiments, the flap is configured to allow a user to pull at least one safety strap attached to the shopping cart seat through the safety strap opening. In some embodiments, the flap has binding around its edges.
[0012] In certain embodiments, the child-seat liner is configured to position within a shopping cart seat. In other embodiments, the child-seat liner is configured to position within a high chair. In further embodiments, the child-seat liner is configured to position within a child's car seat or any other type of child-seat with safety straps.
[0013] In certain embodiments, the article further comprises a handle cover. In some embodiments, the article further comprises a handle cover, wherein the handle cover is connected to (e.g. integral with or sewn to) the front panel. In additional embodiments, the handle cover comprises a securing component (e.g. in order to secure the handle cover to a shopping cart handle such that it does not slip off). In some embodiments, the securing component is selected from elastic, VELCRO, and snaps. In particular embodiments, the article further comprises a rear pouch. In other embodiments, the article further comprises a rear pouch, wherein the rear pouch is connected to (e.g. integral with or sewn to) the back panel. In some embodiments, the rear pouch comprises storage strap fastener. In particular embodiments, the rear pouch comprises a pouch opening. In certain embodiments, the rear pouch comprises a closing component to open and close the pouch opening (e.g. a zipper, VELCRO, or a series of snaps). In certain preferred embodiments, the rear pouch comprises a zipper. In some embodiments, the article further comprises a storage strap.
[0014] In some embodiments, the present invention provides articles (e.g. to protect children) comprising a child-seat liner, wherein the child-seat liner comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a first safety strap opening, and wherein the back panel does not contain a second safety strap opening. In certain embodiments, the back panel comprises additional openings, but none of these openings are configured (e.g. large enough or in the right position) to allow safety straps (e.g. from a shopping cart) to pass therethrough. In particular embodiments, the bottom panel is cushioned (e.g. such that child may sit on it comfortably). In other embodiments, the back panel is cushioned (e.g. such that a child may lean their back against it comfortably). In particular embodiments, the back and/or bottom panel comprise two layers of fabric with a fiberfill type material between the layers of fabric.
[0015] In particular embodiments, the child-seat liner further comprises a front panel connected to the bottom panel. In other embodiments, the front panel further comprises at least one front opening. In some embodiments, the front opening is configured for one leg or two legs of a child sitting in the child seat liner. In preferred embodiments, the front panel further comprises two front openings.
[0016] In other embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel. In some embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel, the back panel, and the front panel. In other embodiments, the child-seat liner does not contain attached safety straps.
[0017] In certain embodiments, the back panel is configured to substantially cover a shopping cart basket back wall (e.g. the back panel covers at least 85%, preferably 95%, or more preferably 99-100% of the back wall). In other embodiments, the bottom panel is configured to substantially cover a shopping cart basket bottom (e.g. the bottom panel covers at least 85%, preferably 95%, or more preferably 99-100% of the bottom). In some embodiments, the front panel is configured to substantially cover a shopping cart basket front wall (e.g. the front panel covers at least 85%, preferably 95%, or more preferably 99-100% of the front wall). In other embodiments, each of the side panels is configured to substantially cover a shopping cart basket side wall (e.g. each of the side panels covers at least 85%, preferably 95%, or more preferably 99-100% of the side walls).
[0018] In certain embodiments, the child-seat liner is configured to position within a shopping cart seat (basket). In other embodiments, the child-seat liner is configured to position within a high chair. In further embodiments, the child-seat liner is configured to position within a child's car seat.
[0019] In certain embodiments, the article further comprises a handle cover. In some embodiments, the article further comprises a handle cover, wherein the handle cover is connected to (e.g. integral with or sewn to) the front panel. In additional embodiments, the handle cover comprises a securing component (e.g. in order to secure the handle cover to a shopping cart handle such that it does not slip off). In some embodiments, the securing component is selected from elastic, VELCRO, and snaps. In particular embodiments, the article further comprises a rear pouch. In other embodiments, the article further comprises a rear pouch, wherein the rear pouch is connected to (e.g. integral with or sewn to) the back panel. In some embodiments, the rear pouch comprises a storage strap fastener. In particular embodiments, the rear pouch comprises a pouch opening. In some embodiments, the article further comprises a storage strap. In certain embodiments, the rear pouch comprises a closing component to open and close the pouch opening (e.g. a zipper, VELCRO, or a series of snaps). In certain preferred embodiments, the rear pouch comprises a zipper.
[0020] In some embodiments, the back panel further comprises a flap, wherein the flap is moveable between a closed position substantially covering the first safety strap opening and an open position that exposes the first safety strap opening. In further embodiments, the back panel further comprises a flap, wherein the flap is moveable between a closed position substantially covering the first safety strap opening (e.g. covering at least 50%, 60%, 75%, 85%, 90%, 95%, 98%, or 100% of the first safety strap opening) and an open position that exposes the first safety strap opening (e.g. at least 5%, 10%, 25%, or 50% of the first safety strap opening is exposed).
[0021] In particular embodiments, the flap has a shape selected from a rectangle, a square, a circle, a half circle, a trapezoid, octagon, a triangle, or a shape similar to one of these shapes. In certain embodiments, the flap has a surface area of at least four square inches or at least five, six, seven, eight, nine, ten, eleven, twelve, fifteen, twenty, twenty-five, thirty, forty, fifty, or at least sixty square inches. In other embodiments, the safety strap opening has a size that is at least five square inches, at least six, seven, eight, nine, ten, eleven, twelve, fifteen, twenty, twenty-five, thirty, forty, fifty, or sixty square inches. In some embodiments, the surface area of the flap is approximately the same size as the first safety strap opening. In preferred embodiments, the safety strap opening is configured to allow both a first safety strap and a second safety strap to pass through the safety strap opening. In other preferred embodiments, the flap is configured to allow a user to pull at least one safety strap attached to the shopping cart seat through the safety strap opening.
[0022] In certain embodiments, the present invention provides articles comprising a child-seat liner cut-piece (e.g. a piece of fabric or filler material that has been cut out based on a child-seat liner pattern). In some embodiments, the present invention provides articles comprising a child-seat liner cut-piece, wherein the child-seat liner cut-piece comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a flap, and wherein the flap is moveable between a closed position and an open position, wherein the open position forms a safety strap opening in the back panel.
[0023] In particular embodiments, the child-seat liner cut-piece further comprises a front panel connected to (e.g. integral with) the bottom panel. In certain embodiments, the front panel further comprises at least one front opening. In other embodiments, the front panel further comprises two front openings. In some embodiments, the child-seat liner cut-piece further comprises two side panels, wherein each of the side panels is connected to (e.g. integral with) the bottom panel.
[0024] In certain embodiments, the back panel is configured to substantially cover a shopping cart basket back wall (e.g. the back panel covers at least 85%, preferably 95%, or more preferably 99-100% of the back wall). In other embodiments, the bottom panel is configured to substantially cover a shopping cart basket bottom (e.g. the bottom panel covers at least 85%, preferably 95%, or more preferably 99-100% of the bottom). In some embodiments, the front panel is configured to substantially cover a shopping cart basket front wall (e.g. the front panel covers at least 85%, preferably 95%, or more preferably 99-100% of the front wall). In other embodiments, each of the side panels is configured to substantially cover a shopping cart basket side wall (e.g. each of the side panels covers at least 85%, preferably 95%, or more preferably 99-100% of the side walls).
[0025] In particular embodiments, the flap has a shape selected from a rectangle, a square, a circle, a half circle, a trapezoid, octagon, a triangle, or a shape similar to one of these shapes. In certain embodiments, the flap has a surface area of at least four square inches or at least five, six, seven, eight, nine, ten, eleven, twelve, fifteen, twenty, twenty-five, thirty, forty, fifty, or at least sixty square inches. In other embodiments, the safety strap opening has a size that is at least five square inches, at least six, seven, eight, nine, ten, eleven, twelve, fifteen, twenty, twenty-five, thirty, forty, fifty, or sixty square inches. In some embodiments, the surface area of the flap is approximately the same size as the safety strap opening. In preferred embodiments, the safety strap opening is configured to allow both a first safety strap and a second safety strap to pass through the safety strap opening.
[0026] In particular embodiments, the child-seat liner cut-piece is configured to be sewn into a child-seat liner. In some embodiments, the child-seat liner cut-piece is configured to be sewn into a child-seat liner, wherein the child-seat liner is configured to position within a shopping cart seat/basket. In other embodiments, the child-seat liner cut-piece is configured to be sewn into a child-seat liner, wherein the child-seat liner is configured to position within a high chair. In further embodiments, the child-seat liner cut-piece is configured to be sewn into a child-seat liner, wherein the child-seat liner is configured to position within a child's car seat.
[0027] In some embodiments, the present invention provides articles comprising a child-seat liner cut-piece, wherein the child-seat liner cut-piece comprises; i) a bottom panel, and ii) a back panel connected to (e.g. integral with) the bottom panel, wherein the back panel comprises a first safety strap opening, and wherein the back panel does not contain a second safety strap opening. In certain embodiments, the child-seat liner cut-piece further comprises a front panel connected to (e.g. integral with) the bottom panel. In other embodiments, the front panel further comprises at least one front opening. In additional embodiments, the front panel further comprises two front openings. In some embodiments, the child-seat liner cut-piece further comprises two side panels, wherein each of the side panels is connected to the bottom panel.
[0028] In certain embodiments, the back panel is configured to substantially cover a shopping cart basket back wall (e.g. the back panel covers at least 85%, preferably 95%, or more preferably 99-100% of the back wall). In other embodiments, the bottom panel is configured to substantially cover a shopping cart basket bottom (e.g. the bottom panel covers at least 85%, preferably 95%, or more preferably 99-100% of the bottom). In some embodiments, the front panel is configured to substantially cover a shopping cart basket front wall (e.g. the front panel covers at least 85%, preferably 95%, or more preferably 99-100% of the front wall). In other embodiments, each of the side panels is configured to substantially cover a shopping cart basket side wall (e.g. each of the side panels covers at least 85%, preferably 95%, or more preferably 99-100% of the side walls).
[0029] In certain embodiments, the first safety strap opening has a size that is at least five square inches, at least six, seven, eight, nine, ten, eleven, twelve, fifteen, twenty, twenty-five, thirty, forty, fifty, or sixty square inches. In other embodiments, the first safety strap opening is configured to allow both a first safety strap and a second safety strap to pass through the safety strap opening.
[0030] In particular embodiments, the child-seat liner cut-piece is configured to be sewn into a child-seat liner. In some embodiments, the child-seat liner cut-piece is configured to be sewn into a child-seat liner, wherein the child-seat liner is configured to position within a shopping cart seat. In other embodiments, the child-seat liner cut-piece is configured to be sewn into a child-seat liner, wherein the child-seat liner is configured to position within a high chair. In further embodiments, the child-seat liner cut-piece is configured to be sewn into a child-seat liner, wherein the child-seat liner is configured to position within a child's car seat.
[0031] In certain embodiments, the back panel further comprises a flap, wherein the flap is moveable between a closed position substantially covering the first safety strap opening and an open position that exposes the first safety strap opening. In some embodiments, the back panel further comprises a flap, wherein the flap is moveable between a closed position substantially covering the first safety strap opening (e.g. covering at least 50%, 60%, 75%, 85%, 90%, 95%, 98%, or 100% of the safety strap opening) and an open position that exposes the first safety strap opening (e.g. at least 5%, 10%, 25%, or 50% of the safety strap opening is exposed).
[0032] In some embodiments, the flap has a shape selected from a rectangle, a square, a circle, a half circle, a trapezoid, octagon, or a triangle. In other embodiments, the flap has a surface area of at least four square inches, at least five square inches, at least six, seven, eight, nine, ten, eleven, twelve, fifteen, twenty, twenty-five, thirty, forty, fifty, or sixty square inches.
[0033] In additional embodiments, the present invention provides systems comprising; a) a shopping cart, wherein the shopping cart comprises a shopping cart basket, and wherein the shopping cart basket comprises a first safety strap and a second safety strap; and b) an article comprising a child-seat liner positioned within the shopping cart basket, wherein the child-seat liner comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a flap, and wherein the flap is moveable between a closed position and an open position, wherein the open position forms a safety strap opening in the back panel.
[0034] In certain embodiments, the safety strap opening allows both the first safety strap and the second safety strap to pass through the safety strap opening. In further embodiments, the shopping cart basket further comprises; i) a shopping cart basket bottom, ii) a shopping cart basket back wall, iii) a shopping cart basket front wall, and iv) two shopping cart basket side walls, and wherein the first and second safety straps are attached to the shopping cart basket back wall or the shopping cart basket bottom. In some embodiments, the safety strap opening allows both the first safety strap and the second safety strap to pass through the safety strap opening.
[0035] In additional embodiments, the back panel substantially covers the shopping cart basket back wall. In other embodiments, the bottom panel substantially covers the shopping cart basket bottom. In further embodiments, the child-seat liner further comprises a front panel connected to the bottom panel. In particular embodiments, the front panel substantially covers the shopping cart basket front wall. In some embodiments, the front panel comprises at least one front opening. In additional embodiments, the front panel further comprises two front openings.
[0036] In some embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel. In other embodiments, each of the side panels substantially covers one of the two shopping cart side walls. In further embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel, the back panel, and the front panel. In other embodiments, the child-seat liner does not contain attached safety straps.
[0037] In some embodiments, the shopping cart further comprises a shopping cart handle, and the article further comprises a handle cover substantially covering the shopping cart handle. In other embodiments, the handle cover comprises a securing component. In certain embodiments, the article further comprises a rear pouch. In certain embodiments, the rear pouch comprises a closing component to open and close the pouch opening (e.g. a zipper, VELCRO, or a series of snaps). In certain preferred embodiments, the rear pouch comprises a zipper.
[0038] In some embodiments, the present invention provides systems comprising; a) a shopping cart, wherein the shopping cart comprises a shopping cart basket, and wherein the shopping cart basket comprises a first safety strap and a second safety strap; and b) an article comprising a child-seat liner, wherein the child-seat liner comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a first safety strap opening, and wherein the back panel does not contain a second safety strap opening. In particular embodiments, the first safety strap opening allows both the first safety strap and the second safety strap to pass through the first safety strap opening.
[0039] In some embodiments, the shopping cart basket further comprises; i) a shopping cart basket bottom, ii) a shopping cart basket back wall, iii) a shopping cart basket front wall, and iv) two shopping cart basket side walls, and wherein the first and second safety straps are attached to the shopping cart basket back wall or the shopping cart basket bottom. In other embodiments, the first safety strap opening allows both the first safety strap and the second safety strap to pass through the safety strap opening. In further embodiments, the back panel substantially covers the shopping cart basket back wall. In certain embodiments, the bottom panel substantially covers the shopping cart basket bottom.
[0040] In additional embodiments, the child-seat liner further comprises a front panel connected to the bottom panel. In some embodiments, the front panel substantially covers the shopping cart basket front wall. In other embodiments, the front panel comprises at least one front opening. In preferred embodiments, the front panel further comprises two front openings. In other embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel. In yet other embodiments, each of the side panels substantially covers one of the two shopping cart side walls. In preferred embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel, the back panel, and the front panel. In some embodiments, the child-seat liner does not contain attached safety straps.
[0041] In other embodiments, the shopping cart further comprises a shopping cart handle, and the article further comprises a handle cover substantially covering the shopping cart handle. In some embodiments, the article further comprises a rear pouch.
[0042] In certain embodiments, the back panel further comprises a flap, wherein the flap is moveable between a closed position substantially covering the first safety strap opening and an open position that exposes the first safety strap opening. In particular embodiments, the back panel further comprises a flap, wherein the flap is moveable between a closed position substantially covering the first safety strap opening (e.g. covering at least 50%, 60%, 75%, 85%, 90%, 95%, 98%, or 100% of the safety strap opening) and an open position that exposes the first safety strap opening (e.g. at least 5%, 10%, 25%, or 50% of the safety strap opening is exposed).
[0043] In some embodiments, the present invention provides methods comprising; a) providing; i) a shopping cart, wherein the shopping cart comprises a shopping cart basket, and wherein the shopping cart basket comprises a first safety strap and a second safety strap; and ii) an article comprising a child-seat liner, wherein the child-seat liner comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a flap, and wherein the flap is moveable between a closed position and an open position, wherein the open position forms a safety strap opening in the back panel; and b) positioning the article in the shopping cart basket, c) moving the flap to the open position, and d) pulling the first and second safety straps through the safety strap opening. In other embodiments, the methods further comprise step d) moving the flap to the closed position. In certain embodiments, the methods further comprise a step after step b), but before step c), of placing a child in the article. In other embodiments, the methods further comprise attaching the first safety strap and second safety strap to each other around the child (thereby securing the child in the seat, and securing the article to the shopping cart basket).
[0044] In some embodiments, moving the flap comprises lifting the flap upwards toward the interior of the article. In other embodiments, moving the flap comprises pushing the flap outward toward the exterior of the article. In some embodiments, pulling the first and second safety straps through the safety strap opening comprises reaching through the safety strap opening and grabbing the first and second safety straps.
[0045] In particular embodiments, the shopping cart basket further comprises; i) a shopping cart basket bottom, ii) a shopping cart basket back wall, iii) a shopping cart basket front wall, and iv) two shopping cart basket side walls, and wherein the first and second safety straps are attached to the shopping cart basket back wall or the shopping cart basket bottom. In some embodiments, positioning the article causes the back panel to substantially cover the shopping cart basket back wall. In other embodiments, positioning the article causes the bottom panel to substantially cover the shopping cart basket bottom. In other embodiments, the child-seat liner further comprises a front panel connected to the bottom panel. In particular embodiments, positioning the article causes the front panel to substantially cover the shopping cart basket front wall. In some embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel. In further embodiments, positioning the article causes each of the side panels to substantially cover one of the two shopping cart side walls.
[0046] In some embodiments, the present invention provides methods comprising; a) providing; i) a shopping cart, wherein the shopping cart comprises a shopping cart basket, and wherein the shopping cart basket comprises a first safety strap and a second safety strap; and ii) an article comprising a child-seat liner, wherein the child-seat liner comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a first safety strap opening, and wherein the back panel does not contain a second safety strap opening; and b) positioning the article in the shopping cart basket, and c) pulling the first and second safety strap openings through the safety strap opening. In certain embodiments, the methods further comprise a step after step b), but before step c), of placing a child in the article. In other embodiments, the methods further comprise attaching the first safety strap and second safety strap to each other around the child (thereby securing the child in the seat, and securing the article to the shopping cart basket).
[0047] In some embodiments, the pulling the first and second safety straps through the safety strap opening comprises reaching through the safety strap opening and grabbing the first and second safety straps. In other embodiments, the shopping cart basket further comprises; i) a shopping cart basket bottom, ii) a shopping cart basket back wall, iii) a shopping cart basket front wall, and iv) two shopping cart basket side walls, and wherein the first and second safety straps are attached to the shopping cart basket back wall or the shopping cart basket bottom. In additional embodiments, positioning the article causes the back panel to substantially cover the shopping cart basket back wall. In further embodiments, positioning the article causes the bottom panel to substantially cover the shopping cart basket bottom. In other embodiments, the child-seat liner further comprises a front panel connected to the bottom panel. In yet other embodiments, positioning the article causes the front panel to substantially cover the shopping cart basket front wall. In some embodiments, the child-seat liner further comprises two side panels, wherein each of the side panels is connected to the bottom panel. In certain embodiments, positioning the article causes each of the side panels to substantially cover one of the two shopping cart side walls.
[0048] In some embodiments, the back panel further comprises a flap, wherein the flap is moveable between a closed position substantially covering the first safety strap opening and an open position that exposes the first safety strap opening. In other embodiments, the method further comprises a step before step c) of moving the flap to the open position. In particular embodiments, moving the flap to the open position comprises lifting the flap upwards toward the interior of the article. In additional embodiments, moving the flap to the open position comprises pushing the flap outward toward the exterior of the article.
[0049] In some embodiments, the present invention provides methods for making a child-seat liner cut-piece comprising; a) providing; i) a child-seat liner pattern, ii) textile material, and iii) a cutting device; and b) cutting the textile material with the cutting device using the child-seat pattern as guide such that a child-seat liner cut-piece is generated. In certain embodiments, the child-seat liner cut-piece generated comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a flap, and wherein the flap is moveable between a closed position and an open position, wherein the open position forms a safety strap opening in the back panel. In particular embodiments, the child-seat liner cut-piece generated comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a first safety strap opening, and wherein the back panel does not contain a second safety strap opening. In certain embodiments, the cutting device is selected from a die cut steel rule press device, a laser cutting device, Gerber cutting device, manual scissors, automatic scissors, a razor blade, or a knife.
[0050] In other embodiments, the present invention provides methods for making a child-seat liner comprising; a) providing; i) a child-seat liner pattern, ii) first textile material, iii) second textile material, iv) filler material, and v) a cutting device, and b) cutting the first textile material, the second textile material, and the filler material with the cutting device using the child-seat pattern as a guide such that a first cut-piece, a second cut-piece, and a filler cut-piece are generated, c) combining the first cut-piece, the second cut-piece and the filler cut-piece such that a child-seat liner is generated with the filler cut-piece between the first cut-piece and the second-cut piece. In certain embodiments, the combining comprises a step of sewing the first cut-piece to the filler cut-piece in order to generate a composite cut-piece. In other embodiments, the combining further comprises a step of sewing the second cut-piece to itself in the form of a child-seat liner. In further embodiments, the combining further comprises a step of sewing the second cut-piece to the composite cut piece.
[0051] In some embodiments, the child-seat liner generated comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a flap, and wherein the flap is moveable between a closed position and an open position, wherein the open position forms a safety strap opening in the back panel. In other embodiments, the child-seat liner generated comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a first safety strap opening, and wherein the back panel does not contain a second safety strap opening. In particular embodiments, the cutting device is selected from a die cut steel rule press device, a laser cutting device, Gerber cutting device, manual scissors, automatic scissors, a razor blade, or a knife.
[0052] In some embodiments, the methods further comprise a step of sewing a handle cover cut-piece to the child-seat liner. In other embodiments, the methods further comprise a step of sewing a rear pouch cut-piece to the child-seat liner.
[0053] In certain embodiments, the present invention provides compositions comprising a steel rule die, wherein the steel rule die is configured to cut a child-seat liner cut-piece, wherein the child-seat liner cut piece comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a flap, and wherein the flap is moveable between a closed position and an open position, wherein the open position forms a safety strap opening in the back panel.
[0054] In some embodiments, the child-seat liners of the present invention (e.g. with a flap or single safety strap opening in the back panel) are located in a transparent (e.g., clear vinyl or other plastic) pouch or bag with a zipper (e.g. for marketing and retail purposes). In additional embodiments, the child-seat liners of the present invention are sold over the Internet.
[0055] In other embodiments, the present invention provides compositions comprising a steel rule die, wherein the steel rule die is configured to cut a child-seat liner cut-piece, wherein the child-seat liner cut piece comprises; i) a bottom panel, and ii) a back panel connected to the bottom panel, wherein the back panel comprises a first safety strap opening, and wherein the back panel does not contain a second safety strap opening.
DESCRIPTION OF THE FIGURES
[0056] [0056]FIG. 1 shows a perspective view of one embodiment of protective article of the present invention.
[0057] [0057]FIG. 2A shows a side view of one embodiment of the protective article of the present invention. FIG. 2B shows a front view of one embodiment of the protective article of the present invention.
[0058] [0058]FIG. 3A shows a side and back view of one embodiment of the protective article of present invention positioned in a shopping cart basket of a shopping cart. This figure shows the rear pouch raised up so that the back of the child-seat liner may be viewed. FIG. 3B shows a side and back view of one embodiment of the protective article of the present invention in a shopping cart basket of a shopping cart. This figure shows the rear pouch hanging over the edge of the shopping cart basket.
[0059] [0059]FIG. 4A shows an aerial view of one embodiment of the protective article of the present invention. FIG. 4B shows a side and top view of the protective article of the present invention. This figure shows the article folded up in storing/carrying position.
[0060] [0060]FIG. 5A shows a top view of an exemplary handle cover cut-piece and handle cover pattern. FIG. 5B shows a top view of one embodiment of a child-seat liner cut-piece and child-seat liner pattern of the present invention. FIG. 5C shows a top view of an exemplary rear pouch cut-piece and rear pouch pattern.
GENERAL DESCRIPTION OF THE INVENTION
[0061] The present invention relates to child-seat liners. Specifically, the present invention provides protective articles comprising child-seat liners, systems comprising child-seat liners, methods for using child-seat liners (e.g. with a shopping cart), and methods for making child-seat liners. The present invention also provides child-seat liner cut-pieces and patterns. In preferred embodiments, the child-seat liners of the present invention comprise a flap that may be moved between an open and closed position. In preferred embodiments, the open position forms a safety strap opening in the back panel of a child-seat liner. In other preferred embodiments, the child-seat liners of the present invention comprise a safety strap opening (e.g. a single safety-strap opening) that allows at least two safety straps to be pulled through and secured around a child.
[0062] The child-seat liners of the present invention have many advantages over other child-seat liners. For example, in some embodiments, the child-seat liners of the present invention allow a single pair of straps (e.g. that are already attached to a shopping cart or high chair) to be easily retrieved by a user through the safety strap opening. This type of configuration allows the straps attached to a shopping cart basket (or other child seat) to be used to secure both the child-seat liner and the child to the shopping cart basket (or other child seat). In this regard, a user will be much less likely to forget to secure the child-seat liner to the child seat (e.g. since it would be obvious if no straps were around the child). This is advantageous as prior child-seat liners have required a user to secure the child in the child-seat liner with one set of straps (e.g., attached to the child-seat liner), and then secure the child-seat liner to the cart with a second pair of straps (e g, attached to the child-seat liner or present in the child-seat itself). Having to secure a second pair of straps (e.g. while coping with a child) is less than ideal and may be dangerous. A user may forget to secure the second pair of straps, thus risking that the child-seat liner will fall out of the child seat (e.g. shopping cart basket), along with the child. This unnecessarily risks injury or death for the child. Furthermore, trying to secure a second pair of straps in the back of child-seat liner wastes time and is difficult as a user usually has to maneuver around to see the straps in order to connect them. This may become even more difficult if a user is attempting to hold a child while securing a second set of straps in the back of the child-seat liner. The child-seat liners of the present invention avoid these problems and allows, in certain embodiments, a user to simply reach through a safety strap opening and retrieve a single pair of straps that may be used to secure both the child-seat liner and child to a child seat (e.g. shopping cart basket). In this regard, in certain embodiments, safety straps attached to a child-seat may be used to simultaneously secure the child and child-seat liner to child-seat.
[0063] In certain embodiments, the child-seat liners of the present invention do not contain attached safety straps. This is an improvement over many previous child-seat liners. For example, manufacturing is simplified and costs are reduced since safety straps do not need to be included. Also, as mentioned above, manipulating a single set of straps saves time and energy for a user.
[0064] The child-seat liners and child-seat liner cut-pieces of the present invention are not limited to any particular configuration. Exemplary configurations are shown in FIGS. 1 - 5 (described in more detail below). Any type of child-seat liner may be modified in accordance with the present invention. For example, child-seat liners may be modified by the addition of a flap in the back (e.g. placing a flap over existing safety strap openings, or cutting a safety strap opening such that a flap is generated). Also, child-seat liners may be modified by creating a single safety-strap opening in the back large enough for two safety straps to pass through. Child-seat liners may also be modified, for example, by removing the safety straps that may be attached to them (i.e. since they would not be necessary if a flap and/or safety strap opening is used in accordance with the present invention). Examples of commercially available child-seat liners (e.g. that may be modified with the teachings of the present invention) include: BUGGYBAGG seat liners available for sale on the internet (that also converts into a diaper bag, see also U.S. Pat. No. 5,829,835 to Rogers et al., herein incorporated by reference for all purposes); FLOPPY SEAT seat liners sold by Floppy Products Inc., Scottsdale, Ariz., see also, U.S. Pat. Nos. 5,967,606 and 6,129,418, both to Bergh et al., and both of which are herein incorporated by reference for all purposes; CLEAN SHOPPER seat liners sold by Babe Ease, LLC, Pelham, HH, (See, also, U.S. Pat. No. 6,129,417, to Cohen-Fyffe, herein incorporated by reference for all purposes).
[0065] Additional child-seat liners (e.g. that may be modified according to the present invention), are found in U.S. Pat. Nos. 5,678,888; 6,206,471; 6,164,721; 4,416,462; 5,967,607; 5,547,250; 6,237,998; 4,204,695; 6,129,417; 6,036,264; 5,897,165; 4,655,502; 4,666,207; 5,330,250; and 4,805,937, all of which are herein incorporated by reference for all purposes.
[0066] The present invention also provides methods of making child-seat liners, and in particular, high volume methods of making child-seat liners. Generally, a child-seat liner pattern is employed (e.g. the pattern serves as a guide for a cutting device to cut a cut-piece). One method of cutting out the cut-piece employs a steel rule die and a steel rule die press. The steel rule die is configured into the shape of the pattern (See, e.g. FIG. 5B for an exemplary shape of steel rule die for a child-seat liner). About 10-12 layers of fabric may be laid on a press and the press brought down such that the steel rule die cuts through all of the layers (resulting in 10-12 child-seat liner cut-pieces in the shape of the steel rule die). Another method for cutting out the cut-pieces from layers of fabric (or other material) employs a system called Gerber cutting. Gerber cutting is a system where about 3-5 layers of fabric (or other material) are laid on a table like component and a sheet of plastic is put over the textile (or other material). The plastic is then vacuum shrunk or compressed to remove air. Then a cutting knife driven by a computer program cuts out the various cut-pieces from the fabric (or other material). Another method for cutting out cut-pieces employs laser cutting. In this method, the pattern is programmed into a computer, and then the computer controls the laser as it cuts the fabric (or other material) into various cut-pieces.
[0067] The present invention also provides methods for constructing child-seat liners from various cut-pieces. For example, three child-seat liner cut-pieces may be cut-out. One of the cut-pieces may be a softer material, and be used on the interior of a child-seat liner. One of the cut-pieces may be a durable material and be used for the exterior of a child-seat liner. The third cut-piece may be a filler material, and be used between the other two components in order to cushion the finished child-seat liner. The child-seat liner may be constructed, for example, by combining the softer material cut piece with the filler material (e.g by sewing these two together) to create a composite. The durable material cut-piece may then be sewn to itself in the shape of a child-seat liner, but be inside-out. The composite may then be placed on top (or inside) of the sewn durable fabric piece, and then sewn on three sides (e.g. along the seams). The durable fabric piece in then turned right side out, and further sewing completed (e.g. attaching a handle cover, or rear pouch, or simply sew up any remaining seams).
DETAILED DESCRIPTION OF THE INVENTION
[0068] Although not limited to any particular configuration, FIGS. 1 - 4 show various preferred protective articles of the present invention. These exemplary embodiments are described below to further illustrate the present invention and are not to be construed as limiting in any manner. Likewise, FIG. 5 shows preferred cut-pieces and patterns of the present invention. These patterns and cut-pieces are also described below to further illustrate the present invention and should be construed as limiting in any manner.
[0069] [0069]FIG. 1 shows an exemplary protective article of the present invention positioned in a shopping cart basket 12 . FIG. 1 shows a child-seat liner connected to a handle cover 9 . Various components of the child-seat liner are shown, including a bottom panel 2 , a back panel 3 , a front panel 4 , and a side panel 5 . The back panel 3 is shown with a safety strap opening 6 and a flap 7 . The front panel 4 is shown with two front openings 8 . The handle cover 9 is shown in a cut away view such that shopping cart handle 11 of shopping cart basket 12 may be seen. In preferred embodiments, the handle cover 9 covers the entire shopping cart handle 11 such that a child seated in the child-seat liner cannot touch any part of the shopping cart handle 11 (e.g. such that the child cannot come into contact with any germs located on the shopping cart handle). Also in preferred embodiments, as shown in FIG. 1, the front, back, bottom, and side panels cover the walls of the shopping cart basket (FIG. 1 shows one shopping cart basket side wall 16 , and the shopping cart basket front wall 17 ). Two safety straps 13 are also shown coming through safety strap opening 6 . Preferably, safety straps are attached to shopping cart basket 12 .
[0070] [0070]FIG. 2A shows a side view of an exemplary protective article of the present invention as it may appear in a shopping cart basket (not shown). FIG. 2A shows a child-seat liner 1 attached to a handle cover 9 and a rear pouch 10 . The handle cover 9 may partially or completely cover, for example, a shopping cart handle such that a child seated in the child-seat liner 1 is not exposed to the filth and germs that may be present on the shopping cart handle. The rear pouch 10 may, for example, dangle off the back of a shopping cart basket. Accessory items, such as a wallet, purse, car keys, coupons, bottles, and childrens toys may be placed in the rear pouch 10 . Only the side panel 5 , and flap 7 , of child-seat liner 1 are shown in this figure. The flap 7 is shown in an open position, extending out the back of child-seat liner 1 .
[0071] [0071]FIG. 2B shows a front view of an exemplary protective article of the present invention. FIG. 2B shows two front openings 8 (e.g. that allow the legs of an infant to pass through), and a front panel 4 of a child-seat liner. Also shown is a handle cover 9 that may, for example, be secured around the handle of a shopping cart. A back panel 3 of a child-seat liner is shown. The back panel 3 is shown with a safety strap opening 6 and a flap 7 . The flap 7 is shown in an open position, but it may be moved to a closed position to substantially cover the safety strap opening 6 .
[0072] [0072]FIG. 3A shows a back and side view of an exemplary protective article of the present invention. The back panel 3 of the child-seat liner is shown attached to a rear pouch 10 . The rear pouch 10 is shown in a raised position such that the back panel 3 of the child-seat liner may be seen. The back panel 3 is shown with a safety strap opening 6 and flap 7 in an open position. Two safety straps 13 are also shown extending through the safety strap opening 6 . The child-seat liner is shown positioned in a shopping cart basket of a shopping cart 15 . A shopping cart basket back wall 18 and shopping cart basket side wall 16 are shown in this figure. The back panel 3 of the child-seat liner is shown substantially covering the shopping cart basket back wall 18 . Likewise, the side panel 5 of the child-seat liner is shown substantially covering the shopping cart basket side wall 16 . This figure also shows a portion of the front panel 4 of the child-seat liner.
[0073] [0073]FIG. 3B shows a back and side view of an exemplary protective article of the present invention. The back panel 3 of the child-seat liner is mostly concealed in this figure by the rear pouch 10 . The rear pouch 10 is shown hanging over the back of a shopping cart basket. The rear pouch is shown with a pouch opening 21 (e.g. in order to stow items in the rear pouch), and a storage strap fastener 20 (e.g. a snap or VELCRO strip that serves as a point of attachment for the storage strap). Also shown is a side panel 5 and a portion of front panel 4 of a child-seat liner positioned in a shopping cart basket of a shopping cart 15 . The child-seat liner is shown resting on a shopping cart basket bottom 19 . A shopping cart basket side wall 16 is shown, and is substantially covered by the side panel 5 of the child-seat liner. This figure also shows a handle cover 9 covering a shopping cart handle.
[0074] [0074]FIG. 4A shows an aerial view of an exemplary protective article of the present invention. A child seat-liner 1 is shown with a bottom panel 2 , two side panels 5 , a front panel 4 , and a back panel 3 . The front panel 4 is shown with two front openings. The back panel 3 is shown with a safety strap opening 6 and a flap 7 . Also shown is a rear pouch 10 attached to back panel 3 . The rear pouch 10 is shown with a storage strap fastener. This figure also shows a handle cover 9 attached to the front panel 4 .
[0075] [0075]FIG. 4B shows a perspective view of an exemplary protective article of the present invention in a storage or carrying configuration (e.g. this shows how the protective article may be folded up for carrying or storage when not in use). A side panel 5 of a child-seat liner is shown, along with a rear pouch 10 . Also shown in this figure is a storage strap 14 (e.g. attached to the front panel), that may be used hold the article in a storage/carrying position (e.g. the storage strap 14 may attach to the storage strap fastener on the rear pouch 10 ).
[0076] [0076]FIG. 5 depicts various cut-pieces or patterns useful for making the protective articles of the present invention. This figure shows the shapes and dimensions for exemplary cut-pieces (e.g. cut out pieces of fabric), as well as patterns useful for generating cut-pieces. FIG. 5A shows an exemplary handle cover cut-piece and handle cover pattern. The dimensions for this cut-piece (and pattern) may vary as the present invention is not limited to any particular dimensions. For example, dimension AA may be about 20-40 inches, preferably about 28-32 inches, and more preferably about 30 and ½ inches. Dimension BB may be, for example, about 10-30 inches, preferably about 18-26 inches, and more preferably about 22 and ½ inches. Dimension CC may be, for example, about 3-20 inches, preferably about 8-12 inches, and more preferably about 10 inches. Dimension DD may be, for example, about 10 to 30 inches, preferably about 15-20 inches, and more preferably about 17 and ¾ inches.
[0077] [0077]FIG. 5B shows an exemplary child-seat liner cut-piece and child-seat liner pattern. This figure may also be considered to show an exemplary die rule. Various areas are shown, including a bottom panel 2 , a back panel 3 (with a flap 7 ), a front panel 4 (with two front openings 8 ), and two side panels 5 . The dimensions for this exemplary cut-piece (and pattern) may vary as the present invention is not limited to any particular dimensions. For example, dimension EE may be, for example about 5-10 inches, and preferably about 7 and ⅞ inches. Dimension FF may be, for example, about 3-8 inches, and preferably about 5 inches. Dimension GG may be, for example, about 1-5 inches, and preferably about 3 inches. Dimension HH may be, for example, about 2-6 inches and preferably about 4 inches. Dimension II may be, for example, about 2-6 inches, and preferably about 4 inches. Dimension JJ may be, for example, about 5-15 inches, and preferably about 8 and ⅝ inches. Dimension KK may be, for example, about 10 to 15 inches, and preferably about 13 inches. Dimension LL may be, for example, about 9 to about 14 inches, and preferably about 12 and ¾ inches. Dimension MM may be, for example, about 9 to about 16 inches, and preferably 13 and ½ inches. Dimension NN may be, for example, about 2-7 inches, and preferably about 5 inches. Dimension OO may be, for example, about 2-6 inches, and preferably about 3-5 inches, and more preferably about 4 inches. Dimension PP may be, for example, about 4-12 inches, and preferably about 8 inches. Dimension QQ may be, for example, about 2-25 inches, preferably about 5-20 inches, more preferably about 7-15 inches, and most preferably about 11 inches (e.g 8 inches, 9 inches, 10 inches, 11 inches, 12 inches or 13 inches).
[0078] [0078]FIG. 5C shows an exemplary rear pouch cut-piece and rear pouch pattern of the present invention. The dimensions for this exemplary cut-piece (and pattern) may vary as the present invention is not limited to any particular dimensions. For example, dimension RR may be, for example, about 12-25 inches, and preferably about 18 and ½ inches. Dimension SS may be, for example, about 5-15 inches, and preferably about 10 inches. Dimension TT may be, for example, about 1-3 inches, and preferably about 2 inches.
[0079] All publications and patents mentioned in the above specification are herein incorporated by reference. Various modifications and variations of the described articles, devices, methods and systems of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. 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 relevant fields are intended to be within the scope of the following claims.
|
The present invention relates to child-seat liners. Specifically, the present invention provides protective articles comprising child-seat liners, systems comprising child-seat liners, methods for using child-seat liners (e.g. with a shopping cart), and methods for making child-seat liners. The present invention also provides child-seat liner cut-pieces and patterns.
| 1
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a 371 International Application PCT/CH2007/000607 filed on 3 Dec. 2007 which claims priority to Swiss Application 00613/07 filed on 13 Apr. 2007.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of connection technology, and relates in particular to a connecting box for connection of wiring to an appliance, in particular for connection of wiring to a photovoltaic module (photovoltaic collector, solar panel, solar cell).
2. Description of Related Art
Photovoltaic solar installations are generally of modular design and comprise a multiplicity of solar cells which are connected via external wiring. In order to achieve a higher voltage, the individual solar cells are connected at least in groups in series, by the positive pole of a first solar cell being connected to the negative pole of a further solar cell. One problem that arises in this case is that, when a solar cell is partially covered, for example, as a result of a shadow thrown by surrounding objects or by clouds, this solar cell becomes passive and contributes only slightly, if at all, to the electricity production. In consequence, when connected in series, the current from the adjacent solar cell flows through the covered solar cell, which can thus be damaged or, at least, its life may be reduced. For this reason, it is known for solar cells to be temporarily bridged by means of an electronic circuit, which generally has diodes as protective elements, and thus to be decoupled from the electricity production during the disturbance. These electronic circuits are frequently accommodated in connecting boxes which are at the same time used for connection of the wiring.
EP999601 from Sumitomo Wiring Systems Ltd. discloses a connecting box for solar cells having a housing with a lower and an upper cover, which can be connected to one another via plug connections. The upper cover has connections for external electrical wiring, as well as electrical plug contacts which are arranged such that, when the housing is in the closed position, they result in an electrical connection to corresponding electrical contacts on the lower cover. Diodes are arranged in the upper cover, and are used for protection of the solar cell. In order to make the arrangement weather-resistant, the diodes are encapsulated in a filler material, for example silicone. One particular disadvantage of these arrangements is that they are unsuitable for present-day high-power solar cells, since they have an inadequate cooling. A further disadvantage is that the proposed encapsulation in silicone unnecessarily increases the material consumption and the weight, and is time-consuming.
U.S. Pat. No. 6,582,249 from Tyco Electronics AMP GmbH discloses a connecting box for solar modules having a housing composed of plastic and having a cover which is connected to a hinge strip. The housing lower part has an opening for connections of a solar panel, and connections for external electrical wiring. Electrical components, for example diodes, are fitted between the connections in the housing lower part. The electrical components may be protected against direct contact by a protective cover which is fitted to the side inner wall of the housing such that it can pivot. The components are preferably encapsulated with a filler material through an opening in the protective cover, after the protective cover has been fixed in the correct position in the housing.
EP1605554 from Mantenimiento Instalaciones Malaga S L discloses a connecting box for solar cells having a housing lower part and a cover with a detachable plug connection. The housing has a first opening for connections of a solar cell, and a second opening for connections of external electrical wiring. A printed circuit board can be mounted in the housing by means of a screw.
German Utility Model DE202005018884U1, from Multi-Holding AG, discloses a connecting box for a solar panel. The connecting box has a housing lower part and a cover which is connected to the housing lower part such that it can pivot. The housing lower part has openings for connections of a solar panel, and has external electrical wiring. Contact elements for attachment of electrical components, in particular diodes, are provided in the interior of the housing. The contact elements are designed such that they are intended to absorb and dissipate the heat which is created by the diodes.
EP1501133 from Tyco Electronic AMP GmbH discloses a connecting box for a solar panel. The connecting box has a housing lower part and a cover which is connected to the housing lower part via a hinge such that it can pivot. In the area of the bottom, the housing lower part has an opening for connections of a solar panel and, in a side wall, it has openings for external electrical wiring. Busbars and contact elements are arranged in the interior of the housing. One embodiment has a printed circuit board with diodes, which are held firmly by holding elements of the housing.
JP20022359389 from Kitani Denki KK, discloses a connecting box for solar cells having a housing with a housing lower part and a removable cover. Openings in the area of the bottom of the housing lower part are used for connection to a solar panel. Openings in a side wall are used for connection of electrical wiring. Diodes which are arranged such that they can be replaced are used as protective elements.
DE102005044939 from Spelsberg Guenther GmbH Co KG discloses a connecting box for solar cells. The connecting box has a protective device, for example in the form of a bypass diode. The printed circuit board is connected to a cooling element, which is passed out of the housing and is connected to the frame of the solar panel, in order to dissipate heat.
One disadvantage of the connecting boxes which are known from the prior art is the inadequate cooling of the electronic components, and the thermal loading of the solar cells which this results in.
One object of the invention is therefore to disclose a connecting box which does not have the disadvantages to which the prior art is subject.
This object is achieved by the invention as defined in the patent claims.
SUMMARY OF THE INVENTION
A connecting box according to the invention generally has an integral or multi-part housing, which surrounds a printed circuit board with electrical/electronic components. Dependent on the embodiment, the housing is formed from a plurality of parts and has a housing lower part and a housing upper part. Alternatively, the housing can be formed by insert molding of the internal parts.
The connecting box is generally designed such that it can be mounted by means of a mounting cap on a base surface, for example the rear face of a solar panel. The mounting cap may in this case be in the form of a separate part, to which a housing part is operatively connected. In order to achieve better force distribution and/or in order to influence convectional cooling, the mounting cap may be designed in a segmented form.
In general, the contact lugs or the contact wires for example of a solar cell are guided into a connecting slot in the connecting box, where they are operatively connected to the printed circuit board via connections which are provided for this purpose. Depending on the embodiment, this connecting slot may be integrally formed peripherally at the edge of the connecting box, or else may be placed within the connecting box. In general, the connecting slot is open at the top and at the bottom.
In one embodiment, external connecting cables are passed into the housing of the connecting box, where they are operatively connected to the printed circuit board (board or stamped grid). If required, the connecting cables have standardized plug connections, thus allowing simple connection externally. Holders for the plug connections and the cables can be provided on the housing of the connecting box, in which the plug connections can be suspended in a defined position for transportation and automatic testing, for example during fitting.
The connecting slot may be closed by a cover, if required. The cover may be designed such that it actively prevents an encapsulation compound that has been introduced but is not yet cured from running out. For example, this means that it is possible to position a completely prefabricated solar panel independently of the position, immediately after the encapsulation of the connecting slot, without the encapsulation compound flowing out again. This shortens the time required for fitting. The cover is advantageously in the form of a displacer, thus reducing the amount of encapsulation compound required for the encapsulation process. In order to monitor the filling level, the cover may, furthermore, be produced from a transparent material.
If required, the cover has one or more openings for introduction of an encapsulation compound and for venting. In one embodiment, the cover has two openings, with one of the two being used for filling, and the other for venting. Since, for example, these are arranged diagonally opposite one another and close to the edge of the encapsulation slot, one of the openings is always lower than the other, thus simplifying the filling process. For example, the opening which is located lower can be filled, as a result of which the air that is enclosed can escape from the connecting slot at the opening which is located higher. Another embodiment has a central opening for filling and one or more vent holes at the edge. Other arrangements are possible. If required, the filling openings have so-called connecting stubs which allow connection of a filling apparatus.
By way of example, the cover of the connecting slot may be closed by snapping in, screwing, adhesive bonding or ultrasound welding, or a combination thereof If the connecting slot is intended to be encapsulated, the cover is preferably designed such that the required encapsulation compound is minimized. For this purpose, the cover has a displacer, for example on its inside, projecting into the connecting slot. Alternatively, a separate part, a displacer, can be introduced into the connecting slot before closure with the cover, without this displacer being integrated in the cover or connected to it. In one embodiment, the cover presses in the intended manner against the connections and against the contact lugs/contact wires, thus improving the electrical contact between the contact lugs/contact wires and the connections. The described type of cover may also be used to close connecting slots of other connecting boxes, and is therefore not restricted to use with the variant disclosed here.
One embodiment of the connecting box is designed such that the rear face of the connecting box does not rest flat on the solar cell, but is held at a certain distance from it by means of the mounting cap. Such raising from the base area has the advantage that the thermal load between the electronic components of the connecting box and the solar panel is reduced. Furthermore, the connecting box may have air guide plates/cooling ribs, which influence the air circulation on the rear face of the box and thus improve the cooling, or prevent heat accumulations. The air guide plates may be produced from the same material as the housing of the connecting box. In order to improve the mechanical robustness and/or to positively influence the air circulation, the air guide plates may be curved, and/or may be used for support on a solar panel in the fitted state. The connecting slot may itself be in the form of a mounting cap. If required, further supports can be provided. The distance between the base area and the rear wall of the connecting box is generally 2-30 mm, although other distances are possible, depending on the embodiment.
In one embodiment, the mounting cap is segmented such that it projects from the connecting box only on two mutually opposite sides thereof, thus assisting free air circulation. Feet which are parts of the mounting cap as well as the lower edge of the connecting slot are operatively connected to the surface of a solar panel, preferably by adhesive bonding. Air channels can be formed by webs on the housing lower part, and assist convectional cooling. The air guide plates are used to pass the air flow around the connecting slot, thus reducing the risk of heat accumulations. Depending on the position of the solar panel and the position of the connecting box on the solar panel, connecting boxes are used which have the webs aligned approximately parallel to the X axis or Y axis, as a result of which the air flow always passes upwards from the bottom.
Alternatively, the webs may also run in any other direction.
Single-layer or multiple-layer solutions may be provided as a printed circuit board for connection of the electrical/electronic components. In addition to etched printed circuit boards with a copper layer applied on an electrically insulating mount material, it is possible to use a grid produced by stamping from a metal sheet (stamped grid). In one corresponding embodiment, the housing has correspondingly designed holding means, for example in the form of snap-action or clamping connections, for holding the stamped grid. Furthermore, stamped grids have the advantage that they can easily be insert molded together with the electronic components arranged on them, in an injection mold. This makes it possible to ensure that the interior is hermetically sealed. A further advantage is that the heat that is created is dissipated efficiently outward through stamped grids or printed circuit boards which rest on the housing.
The sheet-metal thickness of a stamped grid is 0.4 mm, depending on the embodiment. Because it is solid, the board is also used as a cooling plate for the electrical/electronic components. Electrically and thermally sufficiently conductive materials are used as the material. Inter alia, for example, CuSn0.15, CuFe2P or Cu-ETP may be used, in addition to copper, steel or aluminum alloys.
The housing parts of the connecting box are generally designed such that the board rests closely on them, in order to dissipate the heat from the electrical/electronic components via the printed circuit boards and the housing to the exterior. Since, in one embodiment, the electrical/electronic components, for example diodes, as well as the external cables must be connected at least on one side of the board, corresponding cutouts are in each case provided in the housing. One advantage of a stamped grid is that the resultant heat can be dissipated well both downwards and upwards via a housing resting closely on it. In order to further optimize the thermal conductivity between the board and the housing, said cutouts as well as further air spaces, which may be present, are filled with a thermally conductive and electrically insulating compound (for example thermally conductive paste), before the housing is closed.
The housing parts are preferably produced by injection molding or diecasting, although other production methods are also feasible. In general, a sufficiently temperature-resistant material is used for this purpose, for example polyamide (PA), polyphenylether (PPO, PPE), polycarbonate (PC), polybutylene terephthalate (PBT) or polyethylene terephthalate (PET). These materials may be filled with fibers, for example 10% to 60% glass fibers. Other materials are possible, depending on the embodiment.
In order to protect the electronics in the connecting box against moisture and other environmental influences, the housing parts can be sealed from the outside by a circumferential seal. This seal may be in the form of a separate part or may be integrally formed on the housing by means of multicomponent injection molding. It is also feasible to provide a simple circumferential groove in one housing part and a correspondingly projecting circumferential rib in the other housing part, which correspond to one another in the closed position. Alternatively or additionally, the groove can be filled with a sealing compound, for example silicone, before closure. In a further refinement, this groove can be deliberately made larger, such that the sealing compound can be introduced into the resultant cavity retrospectively, when the housing is closed. Corresponding openings and connecting stubs are provided.
In the situation in which a connecting box is intended to be attached using an adhesive which cures slowly, the time required for processing can be bridged by the use of a supplementary holding means. Good results are achieved by means of double-sided adhesive tape. Depending on the field of application, it is possible to also attach the connecting box exclusively by double-sided adhesive tape. Double-sided adhesive tape allows immediate fixing of the connecting box on a base surface, and this can have a positive influence both on the processing time and on automated processing. Further sealing means may be provided between the connecting box and a base surface.
One refinement of a connecting box having a housing and a connecting slot, which is used for connection of at least one electronic component, which is arranged on a printed circuit board in the interior of the housing, to electrical connections of a solar panel, with the housing having a projecting mounting cap which is used for attachment of the connecting box to a surface of the solar panel, is designed such that the rear wall of the housing, when in the fitted state, is at a distance from the solar panel such that this results in convectional cooling of the housing. In this case, the connecting slot can be fitted peripherally to the housing of the connecting box. In a further embodiment, the mounting cap is formed from a variety of parts and can surround the connecting slot. One specific embodiment has at least one adhesive surface for holding an adhesive and/or a double-sided adhesive tape on the mounting cap. A further embodiment of a connecting box has air guide plates which are arranged on the housing rear face. These air guide plates can be designed such that, in the assembled state, they are used to support the housing with respect to a solar panel. It is also possible for the housing to rest at least in places closely on the printed circuit board, as a result of which heat that is created is transported outwards through the housing. The printed circuit board may in this case be in the form of a traditional printed circuit board, a stamped grid or as simple wiring. In a further variant of the connecting box, the housing, which comprises a housing lower part and a housing upper part, closely surrounds the printed circuit board and the at least one electronic component. In particular, the housing may be formed integrally by insert molding of the printed circuit board and the at least one electronic component. In one preferred embodiment, the connecting slot is suitable for holding an encapsulation means.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will be explained in more detail with reference to the following figures, in which:
FIG. 1 shows a perspective illustration of a connecting box obliquely from in front and above;
FIG. 2 shows a perspective illustration of the connecting box shown in FIG. 1 , obliquely from the front and underneath;
FIG. 3 shows a view from underneath of the connecting box shown in FIG. 1 ;
FIG. 4 shows a section illustration along the line DD in FIG. 3 ;
FIG. 5 shows a plan view of the connecting box shown in FIG. 1 , and
FIG. 6 shows a perspective illustration of the connecting box shown in FIG. 1 , with the housing upper part removed, obliquely from the front and above.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a perspective illustration of a connecting box 1 obliquely from the front and above, and FIG. 2 shows the same connecting box 1 obliquely from the front and underneath. FIG. 3 shows the connecting box 1 from underneath, FIG. 4 shows a section illustration (section line DD as shown in FIG. 3 ) from the side, FIG. 5 shows it from above, and FIG. 6 shows it in the open state, obliquely from above.
The figures show a housing 10 , comprising a housing upper part 40 and a housing lower part 20 . The two housing parts 20 , 40 are in this case connected to one another, inter alia, by means of snap-action tabs 18 , that can alternatively or additionally be adhesively bonded to one another, for example, if required. Feet 31 project at the side from the housing 10 and are part of a mounting cap 30 which is segmented here and projects downwards. The mounting cap 30 is used for the actual attachment of the housing 10 to a surface of a solar panel (neither is illustrated in any more detail). In the illustrated embodiment, the mounting cap 30 is an integral component of the housing 10 , but may also be in the form of a separate part. The mounting cap 30 governs the distance A (cf. FIG. 4 ) which is required for convectional cooling on the housing lower face, between a rear wall 19 of the housing and the solar panel 80 .
In the front area, the housing 10 has a connecting slot 60 with connections 52 , which are used for connection of contact lugs or contact wires, for example of a solar panel (none of which is illustrated in any more detail here). The connecting slot 60 is open all the way through and can be closed separately from the rest of the housing 10 . This allows the connecting box 1 to be fitted and closed independently of the assembly process. In consequence, the interior of the connecting box 1 is not subject to any damaging environmental influences. Depending on the embodiment, the connecting slot 60 is open at the top or side. Depending on the field of application, it is arranged in the center of the connecting box 1 , or peripherally.
The connections 52 are operatively connected to a printed circuit board 50 , for example in the form of a stamped grid 50 (cf. FIG. 6 ) or of a board, which is located in the interior of the housing 10 . The connecting slot 60 is likewise a component of the mounting cap 30 . The outer wall of the connecting slot 60 , which essentially has an O-shaped cross section (XY plane) is formed by a circumferential frame 62 , which opens at the lower end into a circumferential mounting surface 69 (adhesive surface). The mounting surface 69 is designed such that it is suitable for holding adhesive and/or double-sided adhesive tape, and can be used for attachment of the housing 10 to the solar panel and/or for sealing of the connecting slot 60 against external influences. Other refinements of a separately closeable connecting slot, for example arranged peripherally on the housing 10 and open at the side with an essentially U-shaped cross section, are possible.
Cable entries 11 can be seen in the area of the connecting box 1 located further backwards, through which connecting cables 70 are introduced into the housing 10 . If the intention is only to connect electronic components to a solar panel, there is no need for external wiring. In the illustrated embodiment, the cable entries 11 are used at the same time as strain relief for the connecting cables 70 , fixing them via a clamping apparatus. In the illustrated embodiment, the connecting cables 70 are terminated by plug connectors 71 , thus allowing simple connection or disconnection, for example to or from an external load. The plug connectors 71 are each fixed by means of a holder 15 , which is arranged at the side on the housing 10 . In this case, the holder 15 comprises a plug bracket 16 and a cable bracket 17 , and is arranged such that the plug connectors 71 are located in a position which is advantageous for automatic functional testing and for transport. A position arranged at the side on the housing 10 has been proven in practical use. However, it is clear to a person skilled in the art that the holder 15 can also be fitted at some other point, or that the plug connector 71 can be held firmly oriented in a different direction.
In FIG. 2 , which shows the connecting box 1 obliquely from underneath, the housing lower part 20 with the connecting slot 60 and the mounting cap 30 , as well as the feet 31 fitted thereto, can be seen. Bulges 24 for electronic components, for example diodes, and cables can be seen on the lower face of the housing lower part 20 .
Air guide plates 23 are integrally formed on the housing lower part 20 and, in the illustrated embodiment, run approximately parallel to one another and to the feet 31 of the mounting cap 30 . The air guide plates 23 extend approximately over the entire extent of the connecting box 1 . The air guide plates 23 may vary in height with respect to one another or within their length, thus also allowing a flow transversely with respect to them. They may be designed at some points to be sufficiently high that, in addition to the feet 31 of the mounting cap 30 , they allow the housing 10 to be supported on the solar panel. In addition to providing robustness and a supporting effect for the housing lower part 20 , the air guide plates 23 also form air channels 25 , thus making it possible to deliberately pass an air flow through them. In the illustrated embodiment, the air guide plates 23 pass the air flow through under the housing 10 and therefore have a positive effect on the cooling of the housing 10 . The S-shaped configuration provides more robustness. Depending on the field of application, the air guide plates 23 may be entirely omitted or may be designed correspondingly differently, for example such that air can also circulate in the lateral direction.
In the illustrated embodiment, the mounting cap 30 has openings 35 at the side, which allow an additional air exchange under the housing lower part 20 .
The mounting cap 30 is designed such that the entire connecting box 1 is raised off a base surface 82 of the solar panel 80 . The feet 31 which project at the side from the mounting cap 30 , and the lower edge of the connecting slot 60 , are formed with adhesive surfaces 32 which are used to hold an adhesive and to which the connecting box 1 is adhesively bonded on the base surface 82 of the solar panel 80 , for example the rear face of a solar cell. In addition to the adhesive surfaces 32 , the feet 31 have second mounting surfaces 33 to which, for example, a double-sided adhesive tape 34 can be fitted. This double-sided adhesive tape 34 allows immediate fixing of the connecting box 1 on the base surface 82 before the adhesive between the adhesive surface 32 and the surface of the solar cell has cured.
FIG. 4 shows a section illustration along the line DD shown in FIG. 3 . In this case, the connecting box 1 is mounted on the base surface 82 , for example the rear face of a schematically illustrated solar panel 80 (the solar panel is not illustrated in FIG. 3 ). Starting from the rear face of the solar panel 80 , contact lugs or the contact wires (not illustrated in any more detail) of the solar cell 81 are introduced into the connecting slot 60 , and are connected there to the connections 52 of the board 50 . In the illustrated embodiment, the contact lugs are soldered to the connections 52 , although alternative forms of making contact, for example using terminals, are feasible. The connecting slot 60 is closed by a cover 63 . The cover 63 has a central opening 66 for filling the connecting slot 60 with an encapsulation compound. Furthermore, the cover 63 is designed such that it projects into the connecting slot 60 , thus reducing the amount of encapsulation compound required to fill the cavity. The encapsulation compound seals the connections 52 of the board 50 as well as the contact lugs or contact wires of the solar cell 81 with respect to environmental influences. The electrical connecting cable 70 is clamped in as strain relief by means of a cable clamp 11 between the housing lower part and the housing upper part.
Circumferentially at their edge, the two housing parts 20 , 40 have a seal 12 which, in the illustrated case, is formed by a tongue and groove system 13 . Alternatively, however, the seal 12 may also be provided by a conventional sealing ring, which is inserted into a groove, either on the housing upper part 40 or on the housing lower part 20 , directly by a sealing compound introduced by means of two-component injection molding, or by a labyrinth seal. The board 50 , with its electrical/electronic components 51 fitted on the lower face, rests flat on the two housing halves 20 , 40 , with diode and cable cutouts 21 , 22 being provided in the housing lower part 20 for the electrical/electronic components 51 and the external connecting cables 70 , which are arranged on the board, where contact is made with them. Alternatively, these cutouts 21 , 22 may be formed in the housing upper part 40 , and the corresponding components may be mounted on the upper face of the board 50 . The board 50 or at least the connections 52 project out of the two closed housing parts 20 , 40 into the connecting slot 60 .
FIG. 6 shows a perspective illustration of the connecting box 1 , with the housing part 40 as shown in FIG. 1 removed, obliquely from the front and above. The figure shows the printed circuit board 50 which has been placed on the housing lower part 20 and is manufactured by stamping from a solid metal sheet (stamped grid). The board 50 is designed to have as large an area as possible in order to dissipate the heat, which is produced in the electrical/electronic components 51 , as efficiently as possible via the housing to the exterior. The board 50 is subdivided by insulating separating joints 54 into subareas which are connected to the connections 52 . The subareas of the board 50 are connected to one another via the electrical/electronic components 51 .
The feet 31 project at the side of the housing lower part 20 and, together with the connecting slot 60 , form the mounting cap 30 . A holder 15 for a plug connection 71 is arranged on each foot 31 , and the plug connection 71 essentially comprises a cable bracket 70 and a plug bracket 16 .
|
The invention relates to a receptacle ( 1 ) particularly suitable for wiring one or more solar cells ( 81 ). The receptacle ( 1 ) comprises a housing ( 10 ) and a connecting shaft ( 60 ) that can be separately closed by a cover ( 63 ). The receptacle ( 1 ) is raised from the back side of the solar panel ( 80 ).
| 7
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application is based on and claims benefit of U.S. Provisional Application No. 60/796,420, filed May 1, 2006. This application is related to U.S. application Ser. No. 11/799,352 (TI-61712) filed May 1, 2007, U.S. application Ser. No. 11/799,181 (TI-63508) filed May 1, 2007, and U.S. application Ser. No. 11/708,820 (TI-62124) filed Feb. 21, 2007.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to multiple power converters used in conjunction, and relates more particularly to a system and method for managing power converters used in conjunction as paralleled phases of a multiphase switching power supply.
2. Description of Related Art
Power supplies are often paralleled to meet particular application goals, such as current or power specifications. Performance improvements in interleaved, multiphase power supplies can be seen from advantages such as reduced input current ripple, reduced peak output current and greater frequency output ripple current. The higher frequency output ripple current permits easier filtering of the output ripple current to remove the ripple. Multiple interleaved phases in switching power supplies also tends to improve power conversion efficiency. A particular type of multiphase switching power supply has a variable switching frequency to obtain desired power supply output characteristics.
A variable frequency switching power supply may operate in various modes at various times, depending upon desired characteristics. For example, a switching power supply may operate in continuous, discontinuous or transition mode, each of which have various advantages. A switching power supply may be constructed to have an inductor that is supplied with current for a given interval and permitted to discharge to a certain extent. Such a switching power supply operating in a continuous mode permits an inductor to discharge to a point where the inductor current is still positive, or above zero, before charging the inductor again. A discontinuous mode switching power supply permits the current in the inductor to drop and remain at zero for a finite time before charging the output inductor again in a subsequent switching cycle. A transition mode switching power supply permits the inductor to discharge to zero current, at which point a new charging cycle begins, so that the inductor current is prevented from becoming negative or remaining zero.
One advantage to transition mode operation is the potential for zero voltage and/or zero current switching in the power supply. Zero voltage switching and zero current switching permits switching losses to be reduced, which can be especially advantageous at high frequencies that are often seen at light loads.
Another advantage to transition mode operation is that it provides a simple way to maintain a desired power factor for a power converter. A typical transition mode configuration for a power converter permits the current in the inductor to achieve a peak value that is proportional to the input voltage. The momentary average of the current through the inductor is proportional to the instantaneous value of the input voltage, which permits the power converter to draw power from an input source at unity power factor. It is desirable to maintain the power factor as close as possible to unity, so that the power converter appears as a purely resistive load on the input power line. Factors that contribute to improving the power factor include maintaining input voltage in phase with input current, and maintaining the input current as a sinusoid when the input voltage is a sinusoid. Transition mode operation tends to help support realization of a good power factor in a variable frequency switching power supply.
A variable frequency transition mode power converter constructed with an inductor can be viewed as a free running oscillator with the switching frequency being controlled by the amplitude of the inductor current. As the load demand decreases, the switching frequency tends to increase as inductor current amplitude decreases. Two or more transition mode power converters may be paralleled to obtain desired operating characteristics, such as a desired output current or power level. The paralleled power converters may also be interleaved and their waveforms synchronized to obtain the advantages discussed above. As switching frequency increases in a paralleled, interleaved power converter during light load conditions, the efficiency of the power converter decreases substantially. The switching losses experienced by the paralleled, interleaved power converters during high frequency switching tend to dominate converter losses over conduction losses. A number of applications for paralleled, or multiphase power converters have loads that can vary significantly, with light load demand extending over relatively long periods of time. It would be desirable to improve the efficiency of multiphase power converters during light load demand intervals.
SUMMARY OF THE INVENTION
An exemplary embodiment of the present invention provides a system and method for managing phases in a multiphase switching power supply. One or more phases in the multiphase power supply are dropped or turned off to reduce the number of active phases supplying power to the power supply output during light load conditions. Similarly, one or more phases in the multiphase power supply are added or turned on to increase the number of active phases supplying power to the power supply during heavy load conditions. The increase or decrease in the number of phases changes the efficiency of the power supply in response to operating conditions.
In an exemplary embodiment, the criteria for turning a phase on or off is based on input power. A control signal realized through a feedback loop provides a voltage that is generally proportional to a power level in the power supply. Alternately, or in addition, a current measure may be taken from current input into power components of the power supply to determine when a phase is to be turned on or off.
According to a feature of the present invention, a phase turn off causes the remaining active phase(s) to be modified to have a greater on-time or gain to produce the same output power as before the phase turnoff. The change in on-time or gain for remaining active phases occurs rapidly in response to phase turnoff. The use of a phase turn off event to cause the change in on-time or gain avoids delays that can occur if a feedback from the overall power supply control loop were used to cause the change.
The phases can be any type of power supply, and may be interleaved and synchronized to obtain the benefits of interleaved multiphase operation. Any number of phases may be employed, and the increase or decrease in number of phases may result in no active phases or a maximum number of phases. The various phases may have different inherent frequencies, the waveforms of which can be synchronized to a given common, or average, frequency.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 a - 1 d are a set of graphs illustrating interleaved multiple phase power supply operation;
FIGS. 2 a - 2 b are block diagrams illustrating paralleled power converters;
FIG. 3 is a circuit block diagram of a two-phase embodiment in accordance with the present invention;
FIG. 4 is a circuit block diagram of a two-phase embodiment in accordance with the present invention;
FIGS. 5 a - 5 b are graphs illustrating current and voltage for a phase-managed PFC power converter;
FIG. 6 is a graph illustrating efficiency versus output power for one- and two-phase operation; and
FIG. 7 is a graph illustrating efficiency versus output power for one- and two-phase operation.
DETAILED DESCRIPTION OF THE INVENTION
This application claims the benefit of U.S. Provisional Application No. 60/796,420, filed May 1, 2006, the entire content of which is hereby incorporated herein by reference.
Referring to FIGS. 1 a - 1 d , plots of input current verses time are illustrated for a single phase power supply and a power supply with two interleaved phases. FIG. 1 a illustrates a single phase power supply that exhibits a significant amount of input current ripple. FIGS. 1 b - 1 d illustrate input current for each of two phases, and the sum of the current of the two phases, respectively. The sum of the two current phases shown in FIG. 1 d produces a current with lower peak current, lower ripple, and a ripple frequency that is twice the frequency of the two input current phases. A variable frequency PWM control may be used to produce an interleaved multiphase power supply with such an advantageous summed current. However, the realization of the variable frequency PWM control is somewhat challenging in that properly synchronizing the separate phases can be difficult when the phases vary in frequency.
Referring to FIG. 2 a , an abstract block diagram of an interleaved multiphase power converter 12 is illustrated. Power converter 12 includes two phases, P 1 and P 2 , that have periodic waveforms controlled to have a phase difference of 180°. A phase detector 14 inspects the waveforms of phases P 1 and P 2 and provides relative phase information to phase generation/control components 16 , 17 . Phase detector 14 provides a relative phase measure to each component 16 , 17 , based on phase information derived from an alternate phase. Accordingly, phase detector 14 inspects the periodic waveform of phase P 2 to provide phase information to component 16 , and inspects the periodic waveform of phase P 1 to provide phase information to component 17 . Each of components 16 , 17 modify phases P 1 and P 2 , respectively, based on the phase information provided by phase detector 14 . As each of components 16 , 17 modify their respective phases P 1 , P 2 , phase detector 14 provides further relative phase information feedback, thereby providing a closed loop relative phase angle difference control.
The periodic waveforms in phases P 1 , P 2 may be power signals that are interleaved to produce a summed output with reduced peak current, reduced ripple, and higher frequency ripple. Alternately, the periodic waveforms in phases P 1 and P 2 can be control signals provided to power components that produce period power waveforms. In the exemplary configuration illustrated in FIG. 2 a , a single phase detector 14 is provided for two phases P 1 and P 2 . The configuration of FIG. 2 a is a special case of the present invention involving two phases, the periodic waveforms of which are separated by 180°.
Referring now to FIG. 2 b , a generalized multiphase interleaved power converter 22 is illustrated. Power converter 22 has a general number of phases N, denoted as phases P 1 -PN. Phase generation/control components 23 , 25 and 27 generate periodic waveforms in each of phases P 1 , P 2 and PN, respectively. Phases P 1 -PN can be combinations of signals for controlling power components to generate periodic power waveforms or the periodic power waveforms themselves. In the general case illustrated in FIG. 2 b , there is a phase detector for each phase in power converter 22 . The feedback provided by phase detectors 24 , 26 and 28 each depend upon two phases to obtain a relative phase measure. Accordingly, the phase information that is received by each phase detector 24 , 26 and 28 is used to obtain a feedback signal to control the generation of a respective phase P 1 -PN to have a desired phase angle separation between the periodic waveforms of phases P 1 -PN. Accordingly, the control of the periodic waveform in each phase P 1 -PN depends upon a phase angle measurement from two different phases. When any of phase detectors 24 , 26 or 28 detect a phase angle difference error, a correction to reduce the error propagates through components 23 , 25 and 27 to adjust relative phase angle difference until the error is reduced for all phases. The propagation of the error through the phases synchronizes the periodic waveforms in each phase to have an overall desired phase angle separation between each phase. By synchronizing the period waveforms, the operating frequencies of phases P 1 -PN tend towards a single frequency, so that phases P 1 -PN is operate at a given frequency. The given frequency tends to be an average of the different independent frequencies of phases P 1 -PN.
Phases P 1 -PN can be in any temporal order with respect to leading or lagging. That is, phases P 1 -PN can be arranged so that phase P 2 lags P 1 and phase PN lags P 2 . Alternately, phases P 1 -PN can be arranged so that phase P 1 lags P 2 or PN or both. The phase detectors 24 , 26 and 28 are arranged to detect the desired relative phase difference in accordance with the temporal order in which phases P 1 -PN are arranged.
Referring now to FIG. 3 , an exemplary embodiment of a control circuit 70 according to the present disclosure is illustrated. In this embodiment, the control signals used to drive the power switches of two separate phases P 1 and P 2 also drive an edge triggered flip-flop 72 . The outputs of edge triggered flip-flop 72 are applied to a control loop filter 74 . Control loop filter 74 provides a phase matching function to provide error signals 76 , 77 that adjust the separation of phases P 1 ,P 2 to track with each other and maintain a desired phase separation. In the two phase example in FIG. 3 , the periodic waveforms in phases P 1 ,P 2 are maintained to have a 180° phase angle difference.
The periodic waveforms in phases P 1 and P 2 are PWM signals that drive power switches used to provide periodic power signals that are interleaved to obtain the advantages of an interleaved, paralleled power supply discussed above. The gate drives are provided through points GDA and GDB based on phases P 1 and P 2 , respectively. The periodic signals in phases P 1 and P 2 are applied to an edge-triggered flip-flop 72 , so that flip-flop 72 receives phase difference information depending upon how the set and reset inputs of flip-flop 72 are activated. The outputs of flip-flop 72 maintain the respective S and R edge-triggered states until reset or set, respectively, by edge-triggered inputs on an alternate input of flip-flop 72 . Accordingly, the desired shape of the outputs of flip-flop 72 are complementary, 50% duty cycle PWM signals. If one or both of the outputs of flip-flop 72 drift away from the complementary, 50% duty cycle relationship, that is, if the outputs of flip-flop 72 do not maintain a 180° phase angle separation, the error is detected and fed back to the appropriate phase control to appropriately advance or retard the respective phase angle. Control loop filter 74 provides logic and signaling to generate an appropriate error signal 76 , 77 , for each phase. Error signals 76 , 77 are applied to multipliers 78 , 79 , respectively, to amplify error signals 76 , 77 on the basis of a feedback error voltage FB in conjunction with an operating reference voltage Vref applied to an amplifier 71 . The output of amplifier 71 , as optionally compensated through input COMP, provides a closed loop reference signal with an overall error component for controlling a power output of the overall interleaved multi-phased power supply.
A control signal 73 provides a control voltage that acts as a threshold to cause a reset in each of phases P 1 ,P 2 , which causes the gate drive signals provided to outputs GDA and GDB to go to a logic low level. The threshold is provided as a ramp that causes a reset in phases P 1 or P 2 when the output of multipliers 78 , 79 exceed the associated ramp values for their respective phases. The ramp signals for each respective phase restart each time an associated phase P 1 or P 2 rises to a logic high level. The outputs of flip-flops 40 , 42 are turned off when the associated ramp reaches a threshold level set by the output of amplifier 71 multiplied by error signals 76 or 77 . Accordingly, the appropriate error signal 76 , 77 influences the respective phase control loop error signal provided by amplifier 71 . Error signals 76 , 77 cause control signal 73 to be increased or decreased to reach a threshold established by the ramp signals in each phase at different times. Flip-flops 76 , 77 are thus reset at a desired time to obtain an adjustment for a phase angle difference between phases P 1 and P 2 . For example, if the phase angle difference between phases P 1 and P 2 is greater than 180°, error signal 76 has a decreased value to decrease the output of multiplier 78 to extend the amount of time needed to meet the threshold established by the ramp in phase P 1 . Accordingly, a reset of phase P 1 is slightly delayed permitting the period of a pulse in phase P 1 to be extended, thereby decreasing the phase angle difference between phases P 1 and P 2 toward 180°. Error signal 76 is similarly increased to retard phase P 1 if the phase angle difference between phases P 1 and P 2 is less than 180°. Error signal 77 operates similarly with respect to phase P 2 to retard or advance phase P 2 by lengthening or shortening the period of the pulse in phase P 2 .
Control circuit 70 also includes a comparator 44 that is set to determine when the number of active phases should be increased or decreased. Compare 44 includes a threshold voltage Vphb that indicates when a phase switch should occur. An input PHB is applied to the inverting input of comparator 44 to signal a low-power or light load condition to indicate a reduction in the number of active phases. Accordingly, when input PHB drops below voltage Vphb, the output of comparator 44 transitions from a logic low level to a logic high level. The output of comparator 44 is applied to a reset input of flip-flop 42 , causing the normal output of flip-flop 42 to be driven to a logic low level. By driving the normal output of flip-flop 42 to a logic low level, phase P 2 is turned off.
Phase P 2 remains disabled while input PHB remains below voltage Vphb. If the demand on the power supply increases, such that the signal applied to input PHB increases above voltage Vphb, the output of comparator 44 is driven to a logic low level, which de-asserts the reset applied to a 42 , permitting phase P 2 to be operated once again.
Control signal 73 provides a control voltage, derived from the output of trans-conductance amplifier 71 and a compensation network optionally applied on a compensation input COMP. The optional compensation network on input COMP is connected between an output of amplifier 71 and ground, so that control signal 73 is compensated based on system characteristics and desired performance, for example. A feedback voltage applied to input FB provides a frequency control for power supply 70 .
In accordance with an exemplary embodiment of the present invention, a compensation network is provide between input COMP and ground to provide compensation for the loop gain contributed by amplifier 71 and the remainder of the regulation loop. The operating level at input comp is thus generally proportional to the power level through the power supply. Inputs COMP and PHB are tied together, so that phase management of phases P 1 , P 2 depends in part on control signal 73 . When input PHB is connected to input COMP, a transition criteria for switching between single and dual phase operation becomes generally proportional to input power. That is, control signal 73 applied to input PHB causes switching between a single active phase and two active phases to be based on input current and input voltage. When input power decreases to level represented by voltage Vphb, phase P 2 is turned off and phase P 1 remains active, thereby increasing the efficiency of power supply 70 at increased switching frequency operation associated with light loads.
Referring now to FIG. 4 , another exemplary embodiment for managing phases in a multiphase power supply 50 is illustrated. A shunt resistor 222 is coupled to the input current of the power supply 50 . The input current corresponds to a sum of the currents in inductors L 1 and L 2 . Accordingly, the voltage across resistor 222 represents the sum of the currents in inductors L 1 and L 2 , and can be used to determine a control for turning phases on or off during heavy or light loads.
The use of input current to determine a low-power condition for turning off phase P 2 , for example, represents an improvement in performance for responding to low demand conditions. For example, the input current measure provided by shunt resistor 222 is continuous and cumulative. Prior current measures in power equipment often depended on measuring output current through a switch, which provided little or no current information when the switch was off. Accordingly, such prior measurements were not continuous, and were specific to a switch or phase rather than overall power supply operation.
The voltage across shunt resistor 222 is a negative voltage value, which is applied to the non-inverting input of comparator 54 , which can be implemented as comparator 44 shown in FIG. 3 . Comparator 54 has a negative reference voltage V ICT applied to the inverting input to act as a threshold for turning phase P 2 on or off. When input current decreases, the magnitude of the voltage on shunt resistor 222 also decreases, that is, it becomes more positive. As the magnitude of the voltage applied the non-inverting input of comparator 54 decreases, it becomes more positive than negative reference voltage V ICT . When the voltage from shunt resistor 222 crosses the threshold represented by negative reference voltage V ICT , comparator 54 produces a logic high output. The logic high output resets flip-flop 56 , which causes phase P 2 to be turned off.
If the load demand on power supply 50 increases, the input current through shunt resistor 222 increases, producing an increased magnitude negative voltage applied to comparator 54 . As the negative voltage across shunt resistor 222 increases in magnitude, that is, becomes more negative, it crosses the threshold represented by negative reference voltage V ICT . The output of comparator 54 then transitions to a logic low level. The logic low level output applied the reset input of flip-flop 56 permits flip-flop 56 to become active and cause switch 213 to switch, reactivating phase P 2 .
The power supplies illustrated in FIGS. 3 and 4 make the gain adjustments to the active phase to accommodate turning a phase on or off. For example, in light load conditions, if phase P 2 is turned off, the on time for phase P 1 is approximately doubled. Similarly, as load demand increases, and phase P 2 is reactivated after having been turned off, the on-time for phase P 1 is decreased to approximately half. The changes in gain made to phase P 1 , for example, are initiated once a determination is made to turn phase P 2 on or off. That is, the gain change applied to phase P 1 occurs as soon as phase P 2 is turned on or off. This rapid change in gain avoids performance issues that may arise if the power supply were configured to have the closed loop gain control operate to change the gain in the phase P 1 . That is, the closed loop gain control of the power supplies illustrated in FIGS. 3 and 4 is typically set to respond relatively slowly to avoid the impact of high-frequency transients. By changing the gain of phase P 1 directly, any performance issues with closed loop control are avoided.
Referring now to FIGS. 5-7 , an illustration of operation of phase management for a multiphase interleaved power converter is provided. While interleaved multiphase operation for a power converter attains a number of advantages as discussed above, light load operation can incur significant switching losses as a result of high frequency switching and parasitic capacitances. In particular, in a transition mode boost power converter the switching frequency increases inversely with the load and with the square of the input line voltage RMS value. Other drawbacks may be observed with high frequency operation of transition mode boost converter with low current levels, such as increased line input current THD, unpredictable converter behavior and increased EMI. In accordance with an exemplary embodiment of the present invention, a transition mode boost converter having multiple interleaved phases disables one or more phases to improve power conversion efficiency and overcome the above-mentioned drawbacks. In accordance with one embodiment, a dual-phase interleaved power converter transitions to single-phase operation to reduce switching losses through operation at lower switching frequency and higher peak current levels as described above. Single-phase operation contributes to overcoming the drawbacks of switching losses that dominate the power stage losses in comparison with conduction losses. FIGS. 6 and 7 illustrate efficiency in single-phase operation at light loads at various operating power levels. As can be seen, the efficiency of operation in waveforms B and D is significantly improved at lower power ranges in comparison with waveforms A and C that reflect two-phase operation.
In operation, one phase of two-phase interleaved transition mode boost power converter is disabled. At the same time, the circuit controlling the on-time for the boost switch of the remaining phase increases the on-time by a factor of approximately 2. The increase in on-time for the remaining boost contributes to smoothing a transition between single and two-phase operation. The peak current is accordingly increased in the boost inductor, and the effective switching frequency is similarly reduced. The lower switching frequency tends to decrease switching losses and improve overall power converter efficiency.
The switch over from two phase to single-phase operation can be provided as a user selectable feature to permit designers to choose a point for phase change-over in relation to switching losses versus the advantages of multi-phased interleaved power conversion. Alternately, or in addition, the point at which phase change-over from two phases to one phase occurs can be set internally or tied to other control signals related to power converter loop control and operational efficiency as described above.
In accordance with an exemplary embodiment of the present invention, a phase change-over to reduce the number of active phases in a multi-phased interleaved power converter is determined based on input current information. The determination of the number of active phases based on input current uses efficiency curves versus input current based on the number of active phases. The efficiency curves may be measured or calculated. Phase activation versus input current may be calibrated with the efficiency curves to obtain a maximum efficiency by selecting the number of active phases based on the given input current. The use of input current information to select the number of active phases to increase efficiency provides better performance and a simpler design than previous solutions that rely on power converter output current determinations. One reason the input current information produced better phase management for improved efficiency is that input current more accurately reflects current transferred in the power converter than typical prior output current measurements. Previous output current measures typically rely on a current measure taken through power switches, which, because they are not always conducting, do not always give information about phase current. Measurement of input current contributes to providing a more consistent view of current flows in the power converter than might otherwise be achieved by inspecting the current flows through the power switches. By determining appropriate levels of input current information for selecting a desired number of active phases, the efficiency of the transition mode boost power converter can achieve greater levels of efficiency and an optimal number of phases being active for a given load and input.
The concept of phase management is not limited to a multiphase interleaved power converter, but can also be used in other power delivery configurations that include multiple power converters. For example, power converters may be connected in parallel to deliver a specified amount of current to a load for a given application. In the event that the load demand drops to a given level, it is desirable to turn off one of the parallel power converters to improve efficiency. The decision on the number of parallel power converters to maintain an active operation, and when a change-over of the number of active parallel power converters should occur is based on input current information in accordance with the present invention. Accordingly, the determination of a number of active power converters arranged in parallel based on input current to improve overall power delivery efficiency is considered to be within the scope of the inventive features of the present disclosure.
It should be emphasized that the above-described embodiments of the present invention are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the invention. Many variations and modifications may be made to the above-described embodiments of the invention without departing substantially from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims.
|
A system and method for managing phases in a multiphase switching power supply turns off a phase in light load conditions and turns on a phase in heavier load conditions. The increase or decrease in the number of phases changes the efficiency of the power supply in response to operating conditions. The phases of the power supply may be synchronized and interleaved. Input current or power representing power supply loading provides a criteria for switching phases on or off. The input current can be taken from an input current sense resistor. The input power can be determined based on a control for managing phases. Turning a phase off causes remaining phases to have an increased on-time or gain to smooth the transition between differing numbers of active phases.
| 7
|
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
The present invention relates to mold apparatus and more particularly to apparatus for facilitating removal and replacement of a single mold in a multi-mold rotational mold configuration which, in addition, facilitates opening of all molds simultaneously.
A molding cycle includes the steps of bringing together two or more mold parts to form a mold having a cavity in which an article may be cast, placing particulate material inside the mold, heating the mold until the material inside is melted, rotating the mold about several different axes so that the entire cavity surface is coated with the melted material and then allowing the mold to cool so that the melted material hardens and forms an article. Rotation about several axis is accomplished by securing the mold to a multi-articular machine which can facilitate the required movement.
Each step in a molding cycle requires a finite amount of time, the total cycle time referred to hereinafter as a cycle period. Process efficiency is generally measured by the number of articles which can be formed in a given period which is directly related to the duration of the cycle period.
To increase process efficiency, the industry has designed mold apparatus which can form several articles during a single cycle period. The most common multi-mold apparatus include several (e.g. 10) molds which are mounted to a “spider” wheel system which includes matching rigid spider wheels. Where each article mold consists of first and second mold halves, each first mold half is secured to a first spider wheel and each second mold half is secured to a second spider wheel. The spider wheels are constructed such that when the wheels are secured together, each second mold half is aligned with a corresponding first mold half forming a mold cavity and the molds are arrayed radially about a rotation axis.
With particulate material in each first mold half, the spider wheels are secured together forming separate yet mechanically linked molds. The spider wheel system is then secured to a multi-articulate machine and the heating, rotating and cooling steps described above are performed. To remove articles from the molds after cooling, the second spider wheel is moved axially away from the first spider wheel simultaneously opening all mold halves. U.S. pat. No. 5,306,564 describes a typical spider wheel system.
Typically spider wheels include rigid legs spaced around their perimeters which cooperate to separate adjacent wheels and form a space therebetween where molds are mounted. While the spacer legs are necessary, the legs limit the types of molds which can be used with a particular spider to a single mold family. In other words, spider wheels are custom built to accommodate specific types of molds.
Sometimes it is desirable to replace either all or a subset of molds which are linked to a multi-articulate machine so that articles having different characteristics can be formed. To replace all molds in a first set with molds in a second set which have different characteristics, one solution has been spider wheel refabrication. Unfortunately, refabrication is extremely time consuming and labor intensive and is therefore relatively costly and thus avoided.
Another solution for replacing mold sets has been to detach a first set of spider wheels and replace the wheels with a second set of wheels specifically designed to accommodate the second set of molds. While replacement requires less time and less labor than refabrication, the extreme complexity of wheel-machine coupling systems makes even the replacement solution relatively labor intensive and time consuming. This is particularly true because spider wheel replacement typically extends the molding cycle period.
The cycle period is extended because system hardware does not facilitate wheel replacement simultaneously with one of the previously mentioned process steps (e.g. heating, rotating, cooling). Generally, mold systems do not facilitate wheel replacement while mold cavities are formed. Instead, replacement is only possible when spider wheels are decoupled from the multi-articulate machine. During a process cycle, except for at the beginning of the cycle when particulate material is placed inside a mold half and at the end of the cycle when a product is removed from a mold, the mold halves must be secured together. Particulate provision and product removal require minimal time and, in any event, require much less time than is needed to decouple spider wheels from a multi-articulate machine and recouple different wheels to the machine to accomplish replacement. Thus, mold replacement necessarily extends a molding process cycle and reduces process efficiency.
To replace a subset of molds on a wheel system the only solution is refabrication which, as indicated above, is time consuming and labor intensive and therefore expensive.
There is, therefore, a need for a mold system which facilitates easy replacement of a mold in a spider wheel system. It would be particularly advantageous if molds could be replaced without separating mold halves and while the spider wheels are secured to an associated multi-articulate machine so that a mold could be removed from the wheels and replaced during a molding process cooling step thereby limiting the time between molding processes.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a mold apparatus for facilitating replacement of rotatable molds comprising first and second frames, wherein the first and second frames include first and second retainers, respectively. The apparatus also includes first and second mold portions which are positionable with respect to each other such that they form a mold, the first and second mold portions including first and second couplers, respectively, which are configured so as to be securely coupled to the first and second retainers, respectively, and a locking member linkable to the frames for securing the frames together so that the frames define a cell.
When the frames are secured together the mold is securable within the cell by securing the couplers to the retainers and the mold is removable from the cell by decoupling the couplers from the retainers. When the frames are not secured together and the couplers are coupled to the retainers, the frames are separable and when separated, the mold portions are in turn separated.
When the frames are secured together, the frames form a plurality of cells, the first and second frames include respective first and second retainers associated with each cell, and the mold includes a plurality of molds (e.g. a separate mold securable within each cell).
Preferably, the cells are arranged radially about an axis and to remove a mold, after decoupling the couplers associated with the mold to be removed from the retainers, the mold is axially lifted from an associated cell. In an alternative embodiment, a mold may be removed, after decoupling the couplers associated with the mold to be removed from the retainers, by radially sliding the mold from an associated cell.
The invention also includes a method for exchanging rotatable molds in a mold apparatus having an upper frame and a lower frame forming a plurality of cells, each retaining one of the rotatable molds, comprising the steps of detaching all connections between one of the rotatable molds and the frames, and removing the detached rotatable mold from the mold apparatus while maintaining the frames in a closed position. In one embodiment the detached mold is removed radially along a plurality of track and rail assemblies coupled to the frames. In an alternative embodiment, where the upper and lower frames are arranged about a rotation axis (i.e. the molds are radially spaced about the axis) the detached mold is axially removable. Each of the axial or radial removal methods further includes the steps of inserting a different mold into a location vacated by mold removal and connecting the different mold to the frames while maintaining frames closed.
The objects of the invention include:
(a) providing a rotatable mold apparatus and an associated method which permit independent removal of molds from, and insertion of molds into, cells defined by the apparatus without having to open the apparatus frames;
(b) providing an apparatus of the above kind which is simple and inexpensive to manufacture and use;
(c) providing an apparatus of the above kind which simplifies the process of swapping different molds within a single apparatus;
(d) providing an apparatus of the above kind which facilitates the use of molds having many different cavity characteristics; and
(e) providing a mold apparatus which facilitates mold replacement simultaneously with another molding process cycle step (e.g. cooling) so that mold replacement does not extend a cycle period.
These and other objects, advantages and aspects of the invention will become apparent from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there are shown preferred embodiments of the invention. Such embodiments do not necessarily represent the full scope of the invention and reference is made therefor, to the claims herein for interpreting the scope of the invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a top plan view of a first embodiment of the inventive mold apparatus;
FIG. 2 is a side perspective view of a cell of the mold apparatus in FIG. 1;
FIG. 3 is a side elevational view taken along line 3 — 3 of FIG. 1;
FIG. 4 is a cross-sectional view taken along line 4 — 4 of FIG. 3 depicting removal of a mold from a cell;
FIG. 5 is a cross-sectional view taken along line 5 — 5 of FIG. 4;
FIG. 6 is a cross-sectional view taken along line 6 — 6 of FIG. 4;
FIG. 7 is a top plan view of a second embodiment of the inventive mold apparatus;
FIG. 8 is a side perspective view of a cell of the mold apparatus in FIG. 7;
FIG. 9 is a top plan view of the upper frame of the mold apparatus in FIG. 7;
FIG. 10 is a cross-sectional view taken along line 10 — 10 of FIG. 9;
FIG. 11 is a cross-sectional view of an engaged fastener as in FIG. 10; and
FIG. 12 is a cross-sectional view of the fastener in FIG. 11, albeit disengaged.
DETAILED DESCRIPTION OF THE INVENTION
Generally, the inventive apparatus includes an upper frame aligned with a lower frame which together define a plurality of cells, each for receiving and containing a separate removable mold. One of the significant advantages provided by the present invention is the ability to remove one or more molds from a mold apparatus without having to separate apparatus frames or remove the spider wheel from an associated multi-articulate machine. In addition, the present invention facilitates installation of one or more molds into the apparatus without having to open apparatus frames or removing the spider wheel from the machine. The invention includes embodiments which facilitate both radial and axial mold exchange. FIGS. 1 through 6 pertain to the first embodiment which facilitates radial mold exchange while FIGS. 7 through 12 pertain to the second embodiment which facilitates axial mold exchange.
1. Radial Embodiment
Referring now to the drawings, wherein like reference characters represent corresponding elements throughout the several views, and more specifically referring to FIGS. 1, 2 and 3 the inventive apparatus 10 which facilitates radial mold exchange includes an upper frame assembly 14 U, a lower frame assembly 14 L and a plurality of molds collectively referred to by numeral 12 . Generally, each of frames 14 U and 14 L are essentially identical and therefore, unless indicated otherwise, only frame 14 U will be described here in detail. Frame 14 U components are identified by a number followed by “U” while similar lower frame 14 L components are identified by an identical number followed by an “L”.
Frame 14 U includes a central coupling structure 18 U, a distal annular frame member 24 U and a plurality of radially extending equispaced “spoke” members (two of which are identified as 20 U and 22 U) which traverse the distance between structure 18 U and frame member 24 U. In addition, proximate structure 18 U, frame 14 U includes separate members which traverse the distance between adjacent spoke members (e.g. 20 U and 22 U), one of which is identified by numeral 30 U. Similarly, other support members 32 U, 28 U and 26 U traverse the distance between each two adjacent spoke members (e.g. 20 U and 22 U) at different radial distances from structure 18 U.
Frame 14 U further includes two track supporting members 19 U and 21 U positioned between each two adjacent spoke members 20 U, 22 U. Each support member 19 U, 21 U is preferably welded to members 32 U, 28 U and 26 U so that adjacent members 19 U and 21 U are parallel, a proximate end is adjacent member 30 U and a distal end is adjacent member 24 U.
Referring to FIG. 2, frame 14 U further includes three spacing/clamping members 34 U, 38 U (only two illustrated, in FIG. 1, location of a third is illustrated at numeral 36 U) for each two adjacent spoke members 20 U and 22 U. Each spacing member is rigidly linked at a proximal end to another frame member and extends perpendicular thereto. Member 34 U is centrally linked to member 30 U while members 36 U and 38 U are secured to spoke members 22 U and 20 U, respectively, adjacent annular member 24 U. As illustrated in FIG. 2, members 34 U, 36 U and 38 U mate and can be clamped to similar members which extend from frame 14 L.
Members 34 U, 36 U, and 38 U may comprise a plurality of different configurations and perform two different functions. First, members 34 U, 36 U and 38 U cooperate with members 34 L, 36 L and 38 L to separate upper frame members (e.g. spokes 20 U, 22 U) from lower frame members (e.g. spokes 20 L, 22 L). Second, although not illustrated in detail with respect to this first embodiment, distal ends of members 34 U, 36 U and 38 U are configured so that they securely and in a locking fashion receive adjacent distal ends of members 34 L, 36 L and 38 L, respectively. To this end, distal ends of members 34 U, 36 U and 38 U may each include a clamp or hook device to secure and lock to adjacent members 34 L, 36 L and 38 L. Alternatively, a subset of members 34 U, 36 U and 38 U may include a locking mechanism. Any type of locking mechanism should suffice which when locked, will maintain frames 14 U and 14 L together. For example, the locking member or mechanism may be as simple as a female/male mating arrangement with one or more bolts which extend through mating ends of adjacent members (e.g. through members 34 U and 34 L).
Although not illustrated, some other type of structure (e.g. hydraulically or pneumatically operated arms) is mechanically linked to each of upper and lower frames 14 U and 14 L, respectively, for, when members 34 U, 36 U and 38 U are not locked to members 34 L, 36 L and 38 L, lifting upper frame 14 U from lower frame 14 L.
Referring still to FIGS. 1, 2 and 3 , frames 14 U and 14 L together define a separate mold receiving cell 52 between each two adjacent spoke members (e.g. 20 U and 22 U) when frames 14 U and 14 L are clamped together in a closed configuration. Generally, a cell 52 is defined by the space bound by four spoke members 20 U, 22 U, 20 L and 22 L, associated members 30 U and 30 L and associated members 24 U and 24 L. Referring also to FIG. 4, when frames 14 U and 14 L are clamped together, all four track supporting member 19 U, 21 U, 19 L and 21 L are parallel and extend radially outward.
Referring also to FIGS. 4, 5 and 6 , a separate retainer or track 64 U, 64 L, 65 U and 65 L is secured (e.g. welded or screwed onto) to each of track supporting members 19 U, 19 L, 21 U and 21 L, respectively, so that four tracks are positioned within each cell 52 . Tracks 64 U and 65 U form a first retainer while tracks 64 L and 65 L form a second retainer.
Each of tracks 64 U, 65 U, 64 L and 65 L has identical characteristics and therefore, to simplify this explanation, only track 65 L will be described in detail. Referring to FIG. 5, track 65 L includes a flat bottom longitudinal member 67 and two lateral members 69 and 73 which extend in the same direction and perpendicular to member 67 . Distal ends of members 69 and 73 curve inwardly toward each other so that track 65 L generally forms a “C” shaped channel 79 which is restricted at the distal ends of members 69 and 73 .
Referring to FIGS. 1, 2 , 3 and 4 , each mold 12 generally includes two mold portions or assemblies, an upper assembly 12 U and a lower assembly 12 L. Each of assemblies 12 U and 12 L are essentially identical and therefore, to simplify this explanation, only assembly 12 L is explained in detail.
Assembly 12 L includes a mold half 81 L and two couplers in the form of rail assemblies 83 L and 85 L. Couplers 83 L and 85 L are configured so as to be coupled to retainers 64 L and 65 L, respectively, such that when coupled, the relative positions of mold portion 81 L and frame member 14 L are invariably locked. Couplers 83 U and 85 U serve a similar purpose in coupling the invariable positions of mold portion 81 U and frame 14 U. Molds formed of halves like half 81 L are well known in the art and therefore are not explained here in detail, suffice it to say that when halves 81 L and 81 U are brought together (see FIG. 3) the halves 81 U and 81 L form a cavity into which meltable plastic particulate can be deposited for melting and forming a molded item.
Assemblies 83 L and 85 L (and for that matter 83 U and 85 U) have similar constructions and therefore, to simplify this explanation, only assembly 85 L is explained here in detail. Referring specifically to FIGS. 2, 5 and 6 , assembly 85 L includes an “L” shaped elongate member 62 , first and second bolts 66 , 80 , first and second nuts 68 , 82 , first and second springs 72 , 86 and a coupler member or rail 74 . L shaped member 62 is sized to extend the length of track 65 L (see FIG. 2) and includes two members 91 and 93 which together form a 90° angle. Member 93 forms first and second apertures 95 and 97 , respectively, at opposite ends of its length.
Rail 74 is essentially the same length as track 65 L and has a width which is less than the distance between members 69 and 73 but greater than the distance between the restricted distal ends of members 69 and 73 . Rail 74 thickness is less than the distance between the restricted ends of members 69 and 73 and member 67 . Rail 74 forms first and second apertures 101 and 103 which are aligned with apertures 95 and 97 when assembly 85 L is constructed. Rail 74 also forms longitudinal surfaces 151 and 153 and lateral rail surfaces 155 and 157 .
Bolt 66 includes a wide head member 99 and a threaded distal end. Similarly, bolt 80 includes a wide head member 105 and a threaded distal end. To attach rail 74 to member 93 , the threaded ends of bolts 66 and 80 are placed through apertures 101 and 103 , through springs 72 and 86 and then through apertures 95 and 97 . Nuts 68 and 82 are then secured to the distal ends of bolts 66 and 80 , respectively.
Referring still to FIG. 5, member 91 is secured to mold half 81 L in any manner known in the art. As illustrated, a preferred method is to weld member 91 to half 81 L at two locations collectively identified by number 71 .
Referring now to FIGS. 2 and 6, stop assemblies (only two 107 L and 109 L illustrated) are provided at the proximate ends of each track 64 U, 64 L, 65 U and 65 L. The stop assemblies are of similar construction and therefore only assembly 109 L is explained here in detail. Assembly 109 L includes a bolt 111 , a square stop member 113 and an anchor member 115 . Stop member 113 is approximately the width of track 65 L and has a similar length dimension. Anchor member 115 is approximately the same width and thickness as rail 74 so that member 115 fits within channel 79 . Member 115 forms an aperture 117 as does stop member 113 (i.e. aperture 119 ). Aperture 117 is threaded so as to securely receive the threaded end of bolt 111 .
To secure assembly 109 L to the proximate end of track 65 L, anchor member 115 is placed within channel 79 at the proximal end of track 65 L, apertures 117 and 119 are aligned, bolt 111 is placed through aperture 119 and is received in aperture 117 . Bolt 111 is tightened until the distal restricted ends of members 69 and 73 are clamped between anchor member 115 and stop member 113 .
Referring now to FIGS. 2 through 6, assuming initially that the upper and lower frames 14 U and 14 L, respectively are clamped together, and that a mold 12 is outside cavity 52 (i.e. disattached from the frames), nuts 68 and 82 are loosened on each attachment assembly so that the distance between each rail 74 and a facing surface of an associated member 93 is greater than the thickness of the distal restricted ends of track members 69 and 73 . Then, as best seen in FIGS. 3 and 4, to position mold 12 within cavity 52 , rails 74 are aligned with adjacent track cavities 73 (see also FIG. 5) and mold 12 is forced radially inward toward structure 18 U (see FIG. 1 ). Eventually the distal ends of rails 74 contact stop members 113 and further inward motion is impeded. At this point, the mold 12 is in the position illustrated in FIG. 2 . Rail 74 lateral surfaces 155 and 157 and track 64 U, 64 L, 65 U and 65 L lateral members 69 and 73 (see FIG. 5) impede lateral motion while rail 74 longitudinal surfaces 151 and 153 and track longitudinal member 67 impede longitudinal motion of mold 12 . To impede radial movement of mold 12 , nuts 68 and 82 are tightened so that the restricted ends of members 69 and 73 are clamped between rail 74 and a facing surface of an adjacent member 93 . Once mold 12 is secured in this fashion, radial mold motion is impeded.
To remove mold 12 from cavity 52 , the above process is reversed. To this end, bolts 68 and 82 are loosened and mold 12 is slid radially out of cavity 52 along tracks 64 U, 64 L, 65 U and 65 L.
Referring to FIGS. 1, 2 and 3 , when molds 12 are secured (i.e. nuts 68 and 82 are tightened) in their respective cavities 52 , by decoupling all claiming members 34 U from 34 L, 36 U from 36 L and 38 U from 38 L, upper frame 14 U can be decoupled from lower frame 14 L. In this case, assuming mold halves 81 U and 81 L are not independently coupled together, frames 14 U and 14 L can be separated, thereby separating all upper mold halves 81 U from adjacent lower mold halves 81 L.
Thus, it should be appreciated that this inventive first system facilitates normal rotational molding procedures whereby a plurality of molds 12 can be simultaneously opened and closed to facilitate rapid deposit of mold particulate material and rapid removal of manufactured products after melting, rotation and hardening. In addition, the inventive apparatus advantageously facilitates removal of any number of the molds 12 separately from frames 14 U and 14 L by detaching rails 74 from adjacent tracks and radial removal of the associated mold 12 . Thus, as illustrated in FIG. 1, many different mold forms can be used with and swapped in and out of a single frame apparatus even while frames 14 U and 14 L are secured (e.g. while manufactured parts are cooling) thereby saving time.
II. Axial Embodiment
The second embodiment is similar to the first embodiment described above in that it includes upper and lower frames 114 U and 114 L, respectively, which can be either locked together to form mold receiving cells, or can be unlocked and separated so that a plurality of mold halves which are coupled to frames 114 U and 114 L can be separated for insertion of particulate molding material or removal of molded products. In addition, even while frames 114 U and 114 L are locked together, one or more molds linked thereto can be delinked and removed from the frames and, if desired, can be replaced. What is different between the second and first embodiments is that, instead of facilitating radial mold removal as in the first embodiment, with the second embodiment molds are removed axially.
Referring to FIGS. 7 through 9, each of frames 114 U and 114 L are very similar. To the extend that frames 114 U and 114 L are similar, only frame 114 U will be explained in detail and differences will be identified throughout. Upper frame 114 U includes a central coupling structure 118 , a distal annular frame member 124 U and a plurality of radially extending equispaced spoke members (two of which are identified as 120 U and 122 U) which traverse the distance between structure 118 U and member 124 U. Frame 114 U also includes brace members (one identified as 130 U) between adjacent spoke members and proximate structure 118 U.
Unique to frame 114 U, and not included on frame 114 L, frame 114 U forms two angle members, exemplary angle members are identified by numerals 111 U and 113 U, each member 111 U and 113 U extending from annular member 124 U to proximate end of one of members 120 U and 122 U, respectively. Also unique to frame 114 U, frame 114 U forms two extension members 115 U and 117 U between each two spoke members. Referring also to FIG. 10, each of members 111 U, 113 U, 115 U and 117 U forms an aperture, the aperture in member 113 U identified by numeral 131 and the aperture in member 117 U identified by numeral 113 .
Referring to FIG. 8, lower frame 114 L also has some unique structure including three additional support members 119 L, 121 L and 123 L between each two adjacent spoke members 119 L, 121 L and 123 L spaced apart between member 130 L and member 124 L, each traversing the distance between adjacent spoke members. Two apertures are formed in opposite ends of each of members 119 L and 123 L, one aperture 151 in member 119 L and one aperture 153 in member 123 L illustrated (see FIG. 10 ).
Referring to FIGS. 8 and 10, three separating assemblies are associated with each adjacent pair of spoke members and are positioned between frames 114 U and 114 L. In FIG. 8, only one stop assembly 159 is illustrated, view of the second and third assemblies blocked. Each assembly 159 includes a rigid stop and an adjustable stop linked at separate ends to frames 114 U and 114 L. The location of the other two stop assemblies associated with spoke members 120 U and 122 U are identified by ends 161 and 163 in FIG. 9 .
In addition, referring still to FIG. 8, a plurality of locking assemblies are also linked between frames 14 U and 14 L, a separate locking assembly located adjacent each separate assembly. Two locking assemblies 155 and 157 are illustrated, however, the location of the other locking assemblies associated with adjacent spoke members 122 U and 12 U is identified by end 165 in FIG. 9 . When frames 114 U and 114 L are brought together locking assemblies 155 , 157 and 165 can be used to lock the frames 114 U and 114 L together. While any locking assembly would suffice, a preferred assembly includes a bolt which extends though an upper frame member and is secured in a bolt receiving member which is securely attached to a similarly positioned and opposing lower frame member. For example, in FIG. 8, assembly 155 generally includes a bolt 220 which extends through member 122 U and is threadably secured within a receiving member 222 which is in turn secured to member 122 L. To lock frames 114 U and 114 L together, bolts 220 are tightened until the stops 159 make contact.
Referring to FIGS. 7, 8 and 10 , when frames 114 U and 114 L are locked together, mold receiving cells are formed between each proximate four spoke members 120 U, 120 L, 122 U and 122 L, associated members 130 U and 130 L and associated members 124 U and 124 L, one cell identified by number 224 .
Referring to FIGS. 7, 8 and 9 , according to the second inventive embodiment, each mold 112 includes two separate mold assemblies 112 U and 112 L. Each assembly 112 U and 112 L includes a mold half similar to the mold halves described above with respect to the first embodiment, and a coupler assembly secured to each mold half. The coupler assembly secured to the upper mold half is identified as 171 while the coupler assembly secured to the lower mold half is identified as 173 .
Assembly 173 includes four member 176 , 177 , 178 and 179 which form a trapezoid wherein opposite members 176 and 178 are parallel and spaced apart a distance equal to the distance between members 123 L and 119 L and where the distance between opposing members 177 and 179 is such that coupler assembly 173 can fit between adjacent spokes 120 U and 122 U and also between opposing members 115 U and 117 U when axially passed therethrough. The lower mold half is secured to assembly 173 .
Importantly when assembly 173 is formed with the dimensions indicated, assembly 173 can fit between members 120 U, 122 U, 130 U and 124 U but will be stopped when members 176 and 178 contact members 119 L and 122 L, respectively. Two linking assemblies 180 , 181 are provided at the ends of member 176 which, when member 176 is adjacent member 119 L, align with the apertures in member 119 L. Similarly, two linking assemblies 182 and 183 are provided in member 178 which, when member 178 is adjacent member 123 L, align with the apertures in member 123 L.
Referring still to FIG. 8, coupler assembly 171 includes a lattice of members which is secured to the upper mold half. While a specific lattice design is illustrated, the important aspect of assembly 117 is that distal ends of some members extend outwardly such that the ends contact members 111 U, 113 U, 115 U and 117 U. Said distal ends are identified by numerals 230 , 231 , 232 and 233 . A linking assembly 185 , 186 , 187 , and 188 is provided at each of distal ends 231 , 230 , 232 and 233 , respectively, which aligns with an aperture in a member 115 U, 117 U, 113 U and 111 U, respectively.
Thus, for each mold 112 there are eight aperture/linking assembly pairs, four pairs associated with each coupler assembly 171 and 173 . First, second, third and fourth pairs comprise linking assemblies associated with assembly 173 and apertures associated with members 111 U, 113 U, 115 U and 117 U, respectively. The fifth and sixth pairs are associated with members 176 and 119 L and the seventh and eighth pairs are associated with members 178 and 123 L. As all linking assemblies are essentially of the same construction, only one assembly 182 will be explained here to simplify this explanation.
Referring to FIGS. 11 and 12, a pair of cross-sectional views show linking assembly 182 in engaged and disengaged positions, respectively. Referring to FIG. 11, assembly 182 includes upper tubular member 190 connected to member 177 at spot weld 194 . Another tubular member 196 is welded within aperture 153 of member 123 L. A socket head cap screw 198 and receiver 200 are connected within the tubular cavity formed between members 190 and 196 . Specifically, socket head cap screw 198 is threadably engageable with the internal threads of receiver 200 . A washer 202 is provided between the head of the socket head cap screw 198 and member 190 . A clevis pin 204 is inserted through apertures in tubular member 196 and receiver 200 , thereby retaining receiver 200 within tubular member 196 . Use of receiver 200 is particularly beneficial as receivers 200 with stripped threads can be easily replaced.
In operation, referring to FIGS. 7 through 12, assuming frames 114 U and 114 L are locked together and at least one mold 112 is secured within a mold cell 224 , to remove the mold 112 without separating frames 114 U and 114 L, each socket head cap screw 198 associated with each linking assembly is loosened. Then, mold 112 is pulled axially from an associated cell along the direction indicated by arrow 240 (see FIG. 10 ). Thereafter mold 112 can be opened separately of frames 114 U and 114 L.
To replace a mold within a cell, the mold is simply dropped down into the cell (i.e. in the direction opposite arrow 240 until members 176 and 178 contact members 119 L and 123 L, respectively, and distal ends 231 , 230 , 232 and 233 contact members 115 U, 117 U, 113 U and 111 U. At this point all linking assemblies should be aligned with associated apertures. Then socket head cap screws 198 are secured within adjacent retainers 200 .
As with the first embodiment, when mold halves 112 U and 112 L are secured to frames 114 U and 114 L, respectively, locking assemblies (see 155 , 157 in FIG. 8) can be unlocked and an overhead hoist (not illustrated) can be used to separate all molds at once.
It should be understood that the methods and apparatuses described above are only exemplary and do not limit the scope of the invention, and that various modifications could be made by those skilled in the art that would fall under the scope of the invention. For example, while various preferred locking and linking assemblies have been described above, clearly any types of such assemblies which can maintain respective components secured together during a molding process cycle are contemplated. In addition, other frame designs are contemplated, the important aspect of the invention being that separate molds can be individually removed from linked frames without having to open all mold halves or remove the spider wheel from the machine and during a typical process cycle step so that the cycle period is not substantially extended to facilitate replacement.
To apprise the public of the scope of this invention, we make the following claims:
|
The present invention includes a mold apparatus for facilitating replacement of rotatable molds therein. First and second frames are provided forming a plurality of mold cells and each mold includes an upper and a lower mold section. The upper mold section is removably coupled to the upper frame, while the lower mold section is removably coupled to the lower frame. Using this arrangement, a mold may be removed by detaching all connections between it and the frames, while maintaining the frames closed. Similarly, a mold may be inserted into a mold cell and connected to the frames while maintaining the frames closed. The removal and insertion operations may be performed radially or axially, depending on frame configuration.
| 1
|
This patent application claims priority to and the benefit of U.S. patent application Ser. No. 61/521,380, filed Aug. 9, 2011 and entitled “Electronically Augmented Mechanical Trash Container Locking Mechanism”, the entire content of which is herein incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The disclosures relate to security and locking mechanisms of residential and commercial trash containers.
2. Description of Prior Art
Commercial and residential trash containers that are designed to be used by garbage collection agencies are usually large containers, which are covered by a lid. There are reasons to lock this lid securely including dispersion of trash due to wind, break-in by animals, and unauthorized access by individuals. Therefore, provisions are often made to lock the lid of a trash container.
In its most basic form, the weight of the lid itself can prevent access to the trash container. This can be combined with a hinge or a sliding mechanism to ensure proper enclosure. When the weight is not sufficient to securely lock the trash can a mechanical latch and/or a lock is usually added that can only be opened by a key.
Such measures can be ineffective or difficult to use as far as the collection process is concerned. A mechanical key usually requires that the operator exit the collection truck to open the container. The operator must also carry and keep track of a large number of keys which can be difficult to manage. Inventions such as U.S. Pat. No. 4,155,584 and U.S. Pat. No. 4,182,530 have been disclosed that take advantage of the mechanical movement of the trash container during the collection process, the weight of the content, the force of gravity, or a combination of these, to unlock upon collection and relock after the container returns to the upright position.
Attempts have been made to refine and improve variants of the mechanical arrangement described above (U.S. Pat. No. 5,015,021, U.S. Pat. No. 7,597,365, U.S. Pat. No. 6,666,485, U.S. Pat. No. 5,085,341, and U.S. Pat. No. 5,213,382.) However, most of the above solutions require complex mechanical parts, which are difficult to retrofit into existing trash and recycling containers. Also, most of these solutions are designed for heavy-duty commercial or bulk trash containers instead of common residential containers, which are usually made of a light material such as plastic or aluminum. Gravity operated mechanisms work for commercial and bulk containers because it is difficult for an individual to pick up and tilt them upside down to circumvent the locking mechanism. Most residential containers, however, can be easily flipped over, compromising the lock. Therefore, such gravity operated locks for residential trash containers are not practical. This invention substantially addresses these issues and others.
SUMMARY OF THE INVENTION
The proposed invention employs a multi step electronically augmented smart locking mechanism for trash containers. The smart lock is attached to the trash container and, in accordance with several embodiments disclosed herein, can be locked and unlocked using electrical, mechanical or a combination of electro-mechanical stimuli.
The lock described herein accomplishes two purposes. First, it allows the owner of the container to unlock it to deposit trash and securely lock it again. Secondly, the locking mechanism correctly recognizes the presence of the collection vehicle and unlocks the container without requiring the operators to employ any additional manipulation other than the ones employed in the daily process of garbage collection.
In one aspect of the present invention, a smart lock locks a trash container in a manner, which prevents the container from being unlocked by tilting and other methods that might be employed to force open the container.
In several embodiments related to this aspect, the smart lock assembly includes one part that can be mounted onto the lid of the trash container and another part that can be mounted onto the trash can. These two parts will interlock through mechanisms to be described below. The top and the bottom parts of the lock may or may not be interchangeable as far as the assembly on the trash container is concerned. Such a smart lock can either retrofit onto existing trash and recycling containers or it can be incorporated into new constructions of such containers.
In several of the embodiments related to this aspect, the smart lock assembly consists of at least two locks referred to herein as the primary lock and the secondary lock.
In at least one of the embodiments, the primary lock is a small but precise contraption that only opens and/or closes upon the correct detection of the presence of an authorized signal. This signal can be applied by the owner or can be generated by the presence of an authorized collection vehicle. Because of the precision of the primary lock it may have fine features such as small size or low consumption of electricity and, therefore, it may be insufficient to prevent forceful opening of the trash container. The secondary lock is a stronger and larger lock that can be opened by a much coarser mechanism, for example when the owner twists a handle or when the truck lifts the container and the acceleration or the force of gravity is applied to the lock, or a certain movement signature is detected. The secondary lock only opens if the primary lock has already opened and, therefore, the primary lock acts as an enabling agent for the second lock.
In another aspect of the invention, the smart lock includes mechanisms to correctly recognize authorized conditions for unlocking the container by the owner of the container. In at least one of the embodiments, the owner unlocks the primary lock using electrical or mechanical stimuli, which also opens the secondary lock, and allows the owner to open the trash container.
Another aspect of the invention relates to the unlocking of the smart lock by collection vehicle operators without requiring the vehicle operators to employ any additional manipulation, which would interrupt the daily collection process. In at least one of the embodiments, a device, such as a remote key, uses electrical stimuli to unlock the primary lock. In at least one embodiment, the unlocking of the primary lock in combination with another electrical or mechanical stimulus, such as the collection vehicle lifting the trash container or the force of gravity, opens the trash container during collection.
As such, the owner of the container can use a signal to lock it when it is placed on the curb on collection day. When the collection vehicle arrives a transmitter on the truck can unlock the primary lock on the container. When the container is picked up or turned upside down the motion can open the secondary lock, which opens the container. After the container is placed back the owner can use the remote controller to lock the container again.
In one form of this invention when the primary lock opens it remains open for a certain preset period of time after which it automatically closes. The same applies to the second lock. This provides not only an automatic mechanism to relock the container after it is opened, it also provides an additional level of security. For example if the presence of the collection truck is sensed but the trash is not collected, and the primary lock is left open indefinitely, the secondary lock may be compromised by intruders if they apply the coarse mechanical motion or electric stimulus that is needed to open the secondary lock. This will also minimize the effort on the side of the container owner to keep it locked.
In one variation of this scheme, one or both of the timers can be programmed to open the locks at predefined times. This can be useful if the collection schedule is known and also if the trucks cannot be equipped with the transmitters needed to send the signal to the smart lock.
This invention can include a fault detection module that can detect conditions in which the lock is not operating properly, such as low battery which by default unlocks or locks the smart lock according to a predefined setting.
Another aspect of this invention is the way energy is supplied to the lock. In one embodiment, where the energy consumption of the lock is low, a solar panel can be attached or built into the surface of the trash container to obtain solar energy. In another embodiment, the lock can be energized by batteries that can be replaced or recharged. In yet another embodiment, energy can be harvested from the mechanical movement of the trash container. In an implementation of this embodiment the mechanical movement of the container, or of the moving parts of the collection truck, can compress a spring or similar energy storing mechanism.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of a conventional residential trash container, including the trash can, the lid, and the smart lock assembly of the present invention.
FIG. 2 is a partial perspective view of FIG. 1 , showing the top of the trash container with an open lid and the smart locking assembly of the present invention.
FIG. 3 shows a front perspective view of the standalone smart locking assembly including a top part that can be mounted onto the lid and a bottom part that can be mounted onto the trash can.
FIG. 4 is a front view of the smart locking assembly with partial details shown.
FIG. 5 is a perspective view of the collection vehicle picking up a trash container with its moving arms during the collection process.
FIG. 6 is a top view of the trash container and the moving arms of the collection vehicle.
FIG. 7 is a top view of the part of the collection vehicle's moving arms, which contains the electronics needed for signal transmission in conjunction with the lock in a wired setting.
FIG. 8 is a top view of the part of the collection vehicle's moving arms, which contains the electronics needed for signal transmission in conjunction with the lock in a wireless setting.
FIG. 9 shows the collection vehicle sending authentication signals to the trash container.
FIG. 10 shows the bottom part of the smart lock assembly and the details of one embodiment of the locking mechanism.
FIG. 11 shows a flow chart of for the locking algorithm of the smart lock.
DETAILED DESCRIPTION OF THE INVENTION
The smart lock inventions and its embodiments disclosed herein are described as applied to a residential trash container. However, these inventions can be applied to a broad range of applications which require secure locking and unlocking mechanisms, for example, but without limitation, commercial trash containers, storage and construction containers, and gated fences.
In one embodiment, depicted in FIG. 1 , the smart lock 101 - 102 can be retrofitted onto an existing trash can 104 and its lid 103 . In another embodiment, the smart lock can be incorporated into the trash can during the manufacturing process. The smart lock in FIG. 2 can consist of a top 201 and a bottom part 202 that latch into each other and are affixed onto parts of the trash container. In the illustrated embodiment of FIG. 2 , the two parts are bolted onto the trash container lid 203 and the can 204 . FIG. 3 is the general outline of the two parts of the lock. At least four holes 301 - 304 allow the locks to be mounted on the lids securely, for example with a bolt 306 and a nut 305 .
The two parts can interlock in a variety of mechanical and electrical ways. In the exemplary depiction of FIG. 4 , the bottom part 402 has a protruding section 408 that can fit into the recessed side 407 of the top part 401 . The shape of the parts of the smart lock and the smart lock's arrangement are not unique. A variety of interlocking mechanisms of the two pieces are disclosed in the claims of this patent.
The implementation of the interlocking mechanism is shown in FIG. 4 . The protruding part 408 of one half of the lock assembly 402 includes two wedge shaped latches 405 , 406 that can provide the interlocking. Once the two parts of the smart lock 401 , 402 are pushed together, 405 and 406 latch into the matching cavities 403 and 404 , and stay locked until the smart locking mechanism comprising the primary and secondary locks allows the release of the latches, thereby unlocking the trash container.
The unlocking of the primary lock is initiated in one of two ways: either the presence of the collection vehicle is sensed by the smart lock or the owner issues an unlock signal in ways described below. Herein these are referred to as primary lock authentication scenarios.
There are many types of locks that can be employed to implement the primary lock. In one embodiment magnetic force can act on pieces of metal to keep them together until the force is removed by proper authentication, hence allowing the lock to open. A common example of this is an electromagnetically driven latch. Another embodiment of the primary lock takes advantage of the force of vacuum to bring separate parts together, thereby interlocking them. Yet another embodiment is to use a hydraulic mechanism in the primary lock to accomplish the same locking effect.
There are many ways to implement the unlocking aspect of the primary lock. To unlock the smart lock for the collection process, in one possible embodiment, the primary lock detects the presence of the collection vehicle through electrical signals. These electrical signals have unique patterns that can be applied to the lock via direct contact with parts of the collection vehicle.
FIG. 5 shows a possible implementation where the collection vehicle 501 uses a mechanical arm 502 to lift the trash container 503 . The mechanical arm of the collection vehicle marked 603 - 605 in FIG. 6 , which has to lift the container 602 , houses the wires carrying the authorization signals inside mechanical arm.
In one embodiment of this aspect, the connection between 603 and 604 and the sides of the trash container 602 can be used as a conductive connection to transfer the signals. This provides a two-wire method for signal transmission from the truck to the trash container. This signal unlocks the primary lock.
In another embodiment of this aspect, the part of the mechanical arm 605 that faces the lock 601 includes the wires carrying the authorization signals. As shown in FIG. 7 , this part 701 touches the smart lock 702 and through a conductive contact 703 transfers the signal to the lock, where it is validated to open the primary lock.
In yet another embodiment of this aspect depicted in FIG. 8 , the part of the mechanical arm 801 that faces the lock 802 houses the wires carrying the authorization signals. 801 sends the signal through a wireless link 803 , to the smart lock 802 , where it is validated to open the primary lock, using any of the publicly used communication protocols, such as infra-red connection, RFID, Bluetooth, WiFi, and other IEEE 802.11 suites of wireless connectivity, or proprietary communication protocols.
In another embodiment shown in FIG. 9 the primary lock in the trash container 902 detects the presence of the vehicle 901 through electrical signals with unique patterns that can be applied via a wireless link 903 to the lock from a transmitter installed inside the vehicle or carried by the vehicle operator. In this embodiment a wireless transmitter that can use any of the publicly used communication protocols such as infra-red connection, RFID, Bluetooth, WiFi, and other IEEE 802.11 suites of wireless connectivity, or proprietary communication protocols, sends the authentication signal to the lock, which, as described above, can unlock the primary lock.
In another embodiment, the lock is equipped with a magnetic card reader that can detect the presence of the authorized collection vehicle when a magnetic medium containing authentication information, such as a magnetic card, is swiped on or into it. This can open the primary lock.
In yet another embodiment, the lock is equipped with an image-processing device, such as, for example, a camera, that detects a certain visual signature of the truck. The visual signature can, for example, be the shape of the vehicle or a bar code printed on the side of it, or a visual signature of the operator, such as face recognition, finger print, etc., and opens the primary lock.
Another possible embodiment is one where the lock is equipped with an audio processing device such as a microphone that detects a unique audio signature of the vehicle or its operator and permits the primary lock to open.
Another possible embodiment is one where the lock is equipped with a proximity sensing device, such as a radar or sonar or infra red sensor that detects a certain distance from the vehicle, and permits the primary lock to open.
Several of the methods described above can be used to allow the owner of the trash container to unlock it. In particular, the RFID or magnetic cards are the most practical methods that can be used by the owner to unlock the trash container.
A variety of embodiments, which include all the abovementioned methods to implement the primary lock, can realize the secondary lock. An exemplary embodiment is shown in FIG. 10 which illustrates the interlocking mechanism and electrical embodiments of the primary and the secondary locks inside the bottom part of the smart lock 402 . When the trash container is closed, the top part of the assembly 401 , which is mounted on the trash container lid, moves down and pushes against the protruding latches 1001 and 1018 . These latches are made of iron or a similar metal that can be affected in a magnetic field. Since the latches are pushed out by the force of small springs 1002 , 1004 , 1016 , and 1017 , the force of the descending top part of the assembly pushes 1001 and 1018 into the frame 1019 , and the top 401 and the bottom 402 parts of the lock come into a complete contact, at which point the latches 1001 and 1018 will be released back by the force of the springs into the cavities 403 and 404 , thereby interlocking the top and bottom parts and securing the trash container. Due to the force of the springs 1002 , 1004 , 1016 , and 1017 which pushes the latches 1001 and 1018 out, pulling the lid up will not result in the opening of the trash container and the assembly remains locked. The primary lock 1013 in this embodiment consists of a detector/timer 1015 that detects one of the various abovementioned authentications such as a wireless signal from the collection vehicle and closes the switch 1014 for a predefined amount of time t 1 . Only during this time, can the secondary lock 1008 be opened. If detector/timer 1009 detects one of the various abovementioned authentications such as the movement signature of the trash container being lifted then it will apply a current to the coil 1010 for a predefined amount of time t 2 . Due to the current flowing in the coil, the magnetic core 1006 is magnetized and pulls the latches 1001 and 1008 into the assembly, thereby allowing the unlocking of the top part 401 attached to the lid and the bottom part 402 attached to the can. Without the closing of the switch 1014 the secondary lock 1008 cannot be activated as this switch is where the current needed to energize the coil 1010 will pass through.
In a different embodiment the secondary lock can be opened by use of mechanical and gravitational forces, gated by the primary lock.
In yet another embodiment, the secondary lock can be opened by the mechanical parts of the truck such as levers, lifting arms, etc.
Other embodiments of this secondary lock may include hydraulic action.
FIG. 11 is the flow chart of the unlocking and locking algorithm implemented in the lock during the normal course of operation when a fault is not detected. In the idle state of this system both primary and secondary locks are locked. When either the presence of the collection vehicle is sensed by the smart lock or the owner issues an unlock signal a primary lock authentication scenario occurs. When a collection vehicle is detected and the primary lock is unlocked, for a specified period of t 1 the smart lock awaits the detection of movement signature or other signals needed to open the secondary lock. After the time t 1 lapses the secondary lock will no longer open and the system returns to the idle state. However, if the secondary lock is opened as a result of the detection of movement signature or other authentication signals, it remains open for a period t 2 which subsequently allows the collection vehicle to empty the trash container during this time. After the time t 2 lapses the system returns to the idle state. When the owner issues an unlock signal by various methods discussed above, the system can be designed to respond in at least two different ways: In one implementation, the system can open both the primary and the secondary locks so the owner can easily deposit trash into the container for a period equal to t 1 , after which the locks close and the system returns to the idle state. A second and more secure implementation is one where a secondary authentication by the owner is necessary within time t 1 of the unlocking of the primary lock to open the secondary lock. For example the owner must turn a handle to open the secondary lock. After the secondary lock is opened, the owner can make the deposit into the trash container within a period of t 2 before the locks close and the system returns to the idle state.
The preceding sections presented various embodiments of an electronically augmented mechanical trash container locking mechanism and applications thereof to securely lock a trash container and prevent unauthorized entry. As one of average skill in the art will appreciate, other embodiments may be derived from the teaching of the present invention without deviating from the scope of the claims.
|
A smart lock that can be built into or mounted onto a trash container with a lid and a can consists of two interlocking parts. The smart lock contains a primary lock operably connected to a secondary lock. The primary lock can be opened in presence of the trash collection vehicle or by a command from the owner. The secondary lock can be opened by the same conditions or when it senses mechanical and gravitational movement characteristics of the collection process, only when the first lock is open. Each lock comprises a timer and electronic circuitry that detects authorized commands and opens the lock.
| 8
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.