Single Member Controls Motive Fluid For Each Working Member Patents (Class 417/347)
  • Patent number: 11231029
    Abstract: A compressor device that periodically supplies compressed working gas to a cooling device loses less gas by not using a rotary valve. The compressor device includes a compressor chamber, a working gas connection, a working liquid connection, a pump, a compensation container and a membrane that is airtight and liquid-tight. The membrane divides the compressor chamber into a first volume containing a working gas and a second volume containing a working liquid. The working gas connection is coupled to the first volume, and the working liquid connection is coupled to the second volume. The pump periodically pumps the working liquid through the working liquid connection and into the second volume and as a result periodically compresses the working gas in the first volume. The membrane is constructed as a balloon or a bellows that surrounds the first volume. The compensation container contains working liquid and is connected to the pump.
    Type: Grant
    Filed: January 21, 2015
    Date of Patent: January 25, 2022
    Assignee: Pressure Wave Systems GmbH
    Inventor: Jens Hoehne
  • Patent number: 9926925
    Abstract: A sludge flow monitoring system and method measures volume of sludge pumped by a positive displacement pump through a pipeline by determining a fill percentage during each pumping cycle. The start and end of each piston stroke are identified by hydraulic system sensors. The fill percentage is determined based upon a first summation of periodic piston speed command values from the start of a pumping stroke to the end of a pumping stroke, and a second summation of periodic piston speed command values from a poppet valve opening indicating output flow from the pump to the end of the pumping stroke.
    Type: Grant
    Filed: September 4, 2014
    Date of Patent: March 27, 2018
    Assignee: Schwing Bioset, Inc.
    Inventors: Charles M. Wanstrom, Thomas M. Anderson, Shahzad M. Khan, Michael M. Mott
  • Patent number: 9062670
    Abstract: A diaphragm machine including a drive unit for producing pulsating hydraulic fluid flows for driving the diaphragms, and a delivery unit for delivering a delivery medium and having pump chambers with volumes that can be varied by the movement of a respective diaphragm. Each pump chamber is connected by a pressure valve to a pressure line and by a suction valve to a suction line. The delivery unit includes at least two hydraulic bodies and a diaphragm body in which the pressure and suction lines are arranged. Each hydraulic body is connected to the drive unit, and formed between each hydraulic body and the diaphragm body is a cavity in which one of the diaphragms is arranged so that by production of the pulsating hydraulic fluid flows, the diaphragms are moved within the cavities and the delivery medium is periodically transferred from the suction line into the pressure line.
    Type: Grant
    Filed: August 3, 2010
    Date of Patent: June 23, 2015
    Assignee: ProMinent GmbH
    Inventor: Horst Fritsch
  • Patent number: 8622720
    Abstract: Reciprocating fluid pumps include a plunger configured to expand and compress in a reciprocating action to pump fluid, and one or more magnets carried by the plunger. The one or more magnets may be used to impart a force on the plunger when the plunger expands and compresses in the reciprocating action within a pump body responsive to a magnetic field. Shuttle valves for shifting flow of pressurized fluid between at least two conduits include a spool movable within a valve body and one or more magnets carried by the spool. The one or more magnets may be used to impart a force on the spool responsive to a magnetic field. Reciprocating fluid pumps may include such shuttle valves. Methods include forming and using such pumps and shuttle valves.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: January 7, 2014
    Inventors: Tom M. Simmons, John M. Simmons, David M. Simmons, Kenji Allen Kingsford
  • Patent number: 7611331
    Abstract: A device and a method for controlling a two-cylinder thick matter pump comprising pistons that are actuated in a push-pull manner by means of a hydraulic reversible pump (6) and hydraulic drive cylinders controlled by said pump. To ensure a reliable operation of the pump the expected length of the stroke of the pistons (8, 8?) in the drive cylinders (5, 5?) is measured and recorded, the stroke time of each conveyance stroke is monitored and compared with the expected stroke duration, and the reversible pump (6) is respectively pivoted, reversing the flow, and/or the pipe switch (56) is reversed when the stroke time exceeds the expected stroke duration by a pre-determined value.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: November 3, 2009
    Assignee: Putzmeister Concrete Pumps GmbH
    Inventors: Stefan Hoefling, Wilhelm Hofmann, Wolf-Michael Petzold
  • Patent number: 6929454
    Abstract: In a thick matter pump, especially for delivering concrete, comprising two delivery cylinders, it is known to provide two position sensors in one of the two cylinders for control of the pistons. However, leakage of hydraulic fluid can lead to an imbalance of the two cylinders. In the invention two position sensors (52?, 52?) are provided, which are arranged at a defined distance from one of the ends of the drive cylinders and which respond to a drive piston (30?, 30?) that is passing by. To prevent the formation of concrete clots inside the delivery cylinders (10) and to prevent the occurrence of a slamming when the drive pistons (30?, 30?) reach their end of travel, the invention provides that both position sensors (52?, 52?) are arranged at a distance from the piston rod-side ends of both drive cylinders (24?, 24?) and, in addition, a correcting sensor (54) is arranged at a defined distance from the piston head-side end of one of the drive cylinders (24?).
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: August 16, 2005
    Assignee: Putzmeister Aktiengesellschaft
    Inventors: Werner Münzenmaier, Wolf-Michael Petzold
  • Patent number: 6779983
    Abstract: A viscous material (sludge) pump, a method of accurately estimating output of such a pump and a method of efficiently managing such a pump. The pump can be the single or double cylinder variety. The pump is calibrated to determine a calibrated sludge-weight output of the pump in terms of a parameter defined as a “lost travel” position of the piston in the pump chamber. This position is defined in terms of the position of the piston in the chamber when the pressure in the chamber reaches a preselected reference pressure expressed in terms of a percentage of the maximum pressure reached in the chamber during a just previous discharge stroke of the piston. The lost travel parameter is used for comparison purposes to accurately estimate actual pump output based on the calibrated pump output at the calibrated value of the lost travel parameter. The pump is managed efficiently by management of the speed of the feed auger.
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: August 24, 2004
    Inventor: David A. Olson
  • Patent number: 6609898
    Abstract: A hydraulic system for a reciprocating piston pump that includes an accumulator for producing a steady-pressure supply of compressible material to a distribution nozzle. The hydraulic system includes an adjustable means for constricting the flow of hydraulic fluid from the accumulator to the hydraulic system. The means for constricting the flow of hydraulic fluid allows the operator to compensate for the type of material being pumped, the vertical distance the material is being pumped, as well as the overall distance the material is being pumped in order to reduce or eliminate line surge. The means for restricting the flow from the accumulator preferably includes a needle valve that allows the operator to select the flow characteristic from the accumulator.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: August 26, 2003
    Assignee: Putzmeister Inc.
    Inventor: James L. Bury
  • Publication number: 20030042017
    Abstract: The invention generally concerns a submersible well pumping system comprising an axially elongated housing having a diameter less than the bore hole of the well, a multi-chamber hydraulically driven diaphragm pump, suspended in the well. The pump is driven by a self-contained, closed hydraulic system, activated by an electric or hydraulic motor. The flow of working fluid into and out of the working fluid sub-chambers is controlled by a two state snap-acting valve, in turn controlled by a control valve which senses the differential pressure across the working diaphragm and generates a hydraulic signal to change the state of the two state snap acting valve, typically when either diaphragm reaches the top of the pumping stroke. Singly or in combination, reliable operation of the two state snap acting valve is assured by adding an energy storage device, hysteresis in the control valves and/or a two position latch on the main valve.
    Type: Application
    Filed: September 3, 2001
    Publication date: March 6, 2003
    Inventor: Leland Bruce Traylor
  • Patent number: 5879137
    Abstract: A high-pressure valve assembly having a valve body that defines a preferably cylindrical valve cavity, a fluid inlet, a fluid outlet and a plurality of valve ports; and a fluid pressure intensifier assembly having a plurality of piston-plunger assemblies and utilizing the high-pressure valve assembly to distribute the working fluid. The valve assemblies have a valve rotor rotatably mounted within the valve cavity. In one embodiment, the valve rotor divides the valve cavity into a high-pressure region in communication with the fluid inlet and a low-pressure region in communication with the fluid outlet. As the valve rotor rotates, at least one and preferably three or more valve ports communicate with the power chamber and at least one and preferably three or more valve ports communicate with the discharge chamber.
    Type: Grant
    Filed: January 22, 1997
    Date of Patent: March 9, 1999
    Assignee: Jetec Corporation
    Inventor: Gene G. Yie
  • Patent number: 5616009
    Abstract: A multicylinder, double acting improved mud pump is disclosed. The preferred embodiment incorporates a hydraulic powered piston in a cylinder which connects with a piston rod which, in turn, drives a second piston in a cylinder adapted to pump fluid mud. The first piston is driven by hydraulic oil delivered under pressure to intake manifolds through an independently driven valving apparatus which times the delivery of the hydraulic fluid for the main power stroke and further times the discharge of the hydraulic fluid for the return secondary power stroke, the system being controlled independently of piston action in timing of multiple pistons in multiple cylinders by the valve system. Additionally an intake valve delivers fluid mud at lower pressure on the intake side of the mud compression piston, and an outlet valve transverses with the piston rod to direct the outlet mud flow.
    Type: Grant
    Filed: August 14, 1990
    Date of Patent: April 1, 1997
    Inventor: J. C. Birdwell
  • Patent number: 5401140
    Abstract: A system and method for controlling operation of a sludge material handling system is disclosed. The sludge material handling system includes a positive displacement piston/cylinder pump, a sludge material feed system which delivers sludge material to the pump, and a sludge material disposal system which receives and disposes of sludge material from the pump. A first parameter is sensed, the first parameter bearing a known relationship to an actual volume of sludge material delivered during a pumping cycle. An output value is determined from the first parameter. A control signal is provided as a function of the output value.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: March 28, 1995
    Assignee: Schwing America, Inc.
    Inventor: Thomas M. Anderson
  • Patent number: 5267838
    Abstract: A severe service compressor for the reliable compression of dirty gasses using compressors with seals cooled by the hydraulic fluids doing the work of compression and seals isolated from the high temperatures of the compressed gasses by piston rings which restrict the flow of compressed gasses into the area adjacent to the seals on the compresion stroke and allow the venting of the gasses adjacent to the seals on the reverse stroke.
    Type: Grant
    Filed: January 3, 1992
    Date of Patent: December 7, 1993
    Inventor: Benton F. Baugh
  • Patent number: 5257912
    Abstract: A system for the transport of high solids sludge includes a positive displacement pump for pumping sludge through a pipeline. The volume of sludge transported is accurately measured by determining the fill percentage during pumping cycle.
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: November 2, 1993
    Assignee: Schwing America, Inc.
    Inventors: Edward A. Oakley, Harry K. Crow, Thomas M. Anderson, Richard T. Atherton, Berthold A. Fehn
  • Patent number: 5205722
    Abstract: An apparatus for continuously pumping fluid at a substantially constant flow rate is disclosed. This apparatus is comprised of a metering pump, a rotary timing valve, at least three fluid transducers, and means for synchronizing said metering pump with said rotary timing valve.
    Type: Grant
    Filed: June 4, 1991
    Date of Patent: April 27, 1993
    Inventor: John M. Hammond
  • Patent number: 5127806
    Abstract: A thick matter pump has two feed cylinders, each including an opening coupled in fluid communication with a material feed tank containing matter to be pumped. A tube switch is adapted to be alternately coupled on its intake side to the openings of the feed cylinders, and on its output side to a delivery pipe to permit the passage of pumped matter therethrough and into the delivery pipe. A shutoff device is supported between the output side of the tube switch and the delivery pipe. The shutoff device is adapted to open to permit the passage of pumped matter therethrough and to close to prevent the passage of pumped matter therethrough in accordance with the difference between the pressure on the input side and the pressure on the output side of the shutoff device, which difference is adjustable by hydraulic or pneumatic means.
    Type: Grant
    Filed: March 29, 1991
    Date of Patent: July 7, 1992
    Assignee: Putzmeister-Werk Maschinenfabrik GmbH
    Inventor: Hartmut Benckert
  • Patent number: 5106272
    Abstract: A system for the transport of high solids sludge includes a positive displacement pump for pumping sludge through a pipeline. The volume of sludge transported is accurately measured by determining the fill percentage by using a material flow signal, measured time intervals, hydraulic fluid pressure, or hydraulic fluid flow rate during each pumping cycle.
    Type: Grant
    Filed: October 10, 1990
    Date of Patent: April 21, 1992
    Assignee: Schwing America, Inc.
    Inventors: Edward A. Oakley, Harry K. Crow, Thomas M. Anderson, Richard T. Atherton, Berthold A. Fehn
  • Patent number: 5088898
    Abstract: A reciprocating pump comprises a plurality of pump sections, each pump section having a suction inlet and a discharge outlet, the inlets all connecting with a common passageway through which the pumped fluid is supplied and the outlets all connecting with a common discharge passageway through which the pumped fluid is discharged. Each pump section includes a bellows which reciprocates to alternately produce suction and discharge strokes, with a change-over period between strokes. A drive control for the bellows delays the start of strokes by the bellows so that when one pump section is in a suction stroke or a change-over period, at least one other pump section is in a discharge stroke. The arrangement reduces variations in pressure in the discharge from the pump.
    Type: Grant
    Filed: October 10, 1990
    Date of Patent: February 18, 1992
    Assignee: Nippon Pillar Packing Co., Ltd.
    Inventors: Toshiyuki Fukumoto, Ryo Imanishi
  • Patent number: 5049038
    Abstract: A two stage fluid compressor is operated by a pneumatically operated relay valve controlled by a fluidic switching device in which switching pulses of pressurized control air are obtained automatically on movement of a compression piston in one of the compression stages.
    Type: Grant
    Filed: October 10, 1990
    Date of Patent: September 17, 1991
    Assignee: Normalair-Garrett (Holdings) Ltd.
    Inventor: Robin H. J. Searle
  • Patent number: 5024584
    Abstract: A pump unit comprising co-operating, push-pull connected reciprocating pumps for the pumping in portions of contents to packing containers on a packing machine. The reciprocating pumps (1) each comprise a control piston (4) connected to the pump piston (6) in control cylinders (18), which are joined together in pairs by means of a connecting pipe (20). The pipe is provided with a flow regulating valve (21) for regulating the flow rate of the hydraulic oil and hence the piston speed. The quantity of hydraulic oil in the connecting pipe can be regulated with the help of a supply tank (23) so that the length of stroke of the pistons can be adjusted.
    Type: Grant
    Filed: November 30, 1988
    Date of Patent: June 18, 1991
    Assignee: Tetra Dev-Co
    Inventors: Giorgio Bordini, Maurizio Vincenzi
  • Patent number: 5020974
    Abstract: A fluid compressor includes a plurality of compression stages each operated sequentially by drive means comprising a pneumatically operated drive piston operating in a drive cylinder. Several embodiments are described and illustrated having different forms of control means and drive and sequencing means for the drive pistons.
    Type: Grant
    Filed: October 31, 1989
    Date of Patent: June 4, 1991
    Assignee: Normalair-Garrett (Holdings) Limited
    Inventor: Robin H. J. Searle
  • Patent number: 4750869
    Abstract: Method and apparatus for transferring and boosting the pressure of gas from a source to a receptacle by sequentially filling and compressing volumes of gas by displacing same with a fluid available at a higher pressure and utilizing pressure differential between the gas and fluid to signal the filling and compressing cycles.
    Type: Grant
    Filed: March 20, 1986
    Date of Patent: June 14, 1988
    Assignee: Booster Technologies, Inc.
    Inventor: Lawrence A. Shipman, III
  • Patent number: 4729720
    Abstract: An apparatus for generating high hydraulic pressure with reduced pulsations, comprising a valve case attached to a motor main body and having a plurality of pneumatic cylinder units arranged therearound, a rotary valve rotatably fitted in the valve case, links each having one end pivoted to the piston of each pneumatic cylinder unit and the other end connected to an eccentric shaft portion provided on a crank shaft or the rotary valve, and hydraulic bases connected directly to the pneumatic cylinder units individually, the hydraulic pressure fluid being caused to flow-out from the hydraulic bases in succession by the rotation of the rotary valve, in such a manner that when the outflow of the fluid from one of the hydraulic bases is about to cease, the fluid starts to flow out from another hydraulic base, and when the flows of hydraulic fluid from the two hydraulic bases combine, the pulsation of the flow from one base is offset by that of the other single flow, making it possible for the hydraulic fluid to un
    Type: Grant
    Filed: July 25, 1986
    Date of Patent: March 8, 1988
    Assignee: Osaka Taiyu Co., Ltd.
    Inventor: Hiromu Fujita
  • Patent number: 4718826
    Abstract: Mounted on a mobile platform, a dual hopper mixing tank having a hydraulically operated slide gate controlling the exit of a slurry. The mixed slurry is gravity fed to a pair of hydraulically operated pumps with the stroke of the pistons therein controlled by a reed switch or an IC chip. An outlet nozzle end from the pumps leads to a Y-shaped hose for supplying slurry continuously to a work site.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: January 12, 1988
    Inventor: Richard C. Simmer
  • Patent number: 4714411
    Abstract: A fluid pressure intensifier device particularly suited for intensifying the pressure of a gas has a plurality of piston and cylinder compression stages of sequentially reducing volume connected by flow passages (FIG. 5b) for conducting fluid to be pressure intensified sequentially through the compression stages. Individual pressure fluid powered driving mechanisms for each piston or cylinder compression stage comprise driving piston and cylinder assemblies controlled to operate in sequence by a rotatable port plate. The port plate is rotatable by a positive displacement pressure fluid motor actuated by the pressure fluid powering the driving piston and cylinder assemblies, the outer gear of the motor being constituted by the rotatable port plate.
    Type: Grant
    Filed: June 16, 1986
    Date of Patent: December 22, 1987
    Assignee: Normalair-Garrett (Holdings) Limited
    Inventor: Robin H. J. Searle
  • Patent number: 4690622
    Abstract: The unit comprises three liquid intensifiers, coupled together in juxtaposition, and fixed between a pair of plates. A support plate at the one end of the intensifiers mounts a rotary valve which, sequentially, supplies operative, low-pressure fluid to the intensifiers. A base plate at the other end of the intensifiers admits liquid into each thereof, for pressure intensification of the liquid by the intensifiers, and provides a common outlet aperture for the pressurized liquid.
    Type: Grant
    Filed: August 7, 1986
    Date of Patent: September 1, 1987
    Assignee: Ingersoll-Rand Company
    Inventor: Robert W. Decker
  • Patent number: 4687422
    Abstract: A dual pump is disclosed in which a single valve controls flow of power fluid to the pump piston. Cams on the pistons and push rods on the valve interact to control the valve timing.
    Type: Grant
    Filed: May 30, 1986
    Date of Patent: August 18, 1987
    Inventor: Francis J. Fuchs, Jr.
  • Patent number: 4676724
    Abstract: A multicylinder, improved mud pump is disclosed, the preferred embodiment incorporating a hydraulically powered piston in a cylinder which connects with a piston rod which, in turn, drives a second piston in a cylinder adapted to pump mud. The first piston is driven by fluid from a rotary distribution valve, with the distribution valve being driven independently from the movement of the piston; also, the piston can be driven on its return stroke by entrapped fluid routed from a second cylinder, or the piston can be driven on its return stroke by fluid routed from the valve. Additinally novel valving means is disclosed for the rotary distribution valve and novel hydraulic drive circuitry is disclosed, also novel mud pumping valve and piston arrangements are disclosed.
    Type: Grant
    Filed: January 16, 1985
    Date of Patent: June 30, 1987
    Inventor: J. C. Birdwell
  • Patent number: 4621988
    Abstract: The unit comprises three liquid intensifiers, coupled together in juxtaposition, and fixed between a pair of plates. A support plate at the one end of the intensifiers mounts a rotary valve which, sequentially, supplies operative, low-pressure fluid to the intensifiers. A base plate at the other end of the intensifiers admits liquid into each thereof, for pressure intensification of the liquid by the intensifiers, and provides a common outlet port for the pressurized liquid.
    Type: Grant
    Filed: September 16, 1985
    Date of Patent: November 11, 1986
    Assignee: Ingersoll-Rand Company
    Inventor: Robert W. Decker
  • Patent number: 4611973
    Abstract: Improved mud pump comprised of plural cylinder pumping units, each cylinder unit consisting of a pumping compression chamber and two or more hydraulic driven expansion chambers, with one or more expansion chambers being employed to drive a pumping plunger to cause fluid to be pumped through the compression chamber, also one or more of said expansion chambers being employed to return the plunger; the plunger further being employed as the housing for one or more of the said expansion chambers. The invention includes novel hydraulic drive circuitry and novel hydraulic distribution valving means for control of the hydraulic drive fluid that is utilized to drive the expansion chamber of each cylinder pumping unit. The invention also includes novel positioning means for the unidirectional inlet and outlet mud pumping valves.
    Type: Grant
    Filed: September 6, 1983
    Date of Patent: September 16, 1986
    Assignee: P & B Industries
    Inventor: J. C. Birdwell
  • Patent number: 4606709
    Abstract: An intensifier pump has a primary fluid cylinder including a primary piston and which has shaft portions received within a separate coaxial fluid chamber. A secondary fluid cylinder having a secondary piston has shaft portions reciprocally received within a separate coaxial fluid chamber. The secondary piston is of a smaller relative diameter than the primary piston. The sizing of the hydraulic pistons in the operating fluid cylinders is used to sequence the pistons in the cylinders with the largest diameter piston being stroked first followed by the second largest diameter cylinder being stroked next, followed in turn by any additional fluid cylinders in the order of the piston diameter size. When the smallest diameter cylinder has been stroked, a pressure switch signals a reverse flow pump to change the direction of circulation of the operating fluid to cycle the pistons.
    Type: Grant
    Filed: August 26, 1985
    Date of Patent: August 19, 1986
    Assignee: Special Projects Mfg. Co.
    Inventor: James P. Chisolm
  • Patent number: 4527959
    Abstract: A pump is provided for circulating drilling fluid and the like into a well during a well drilling process. The pump comprises a pair of double-ended piston assemblies hydraulically reciprocated in opposite directions by a common hydraulic drive arrangement, wherein each piston assembly has a relatively large piston at one end and a relatively small piston at an opposite end. The various pistons reciprocate within appropriately sized cylinders each having a working end with a one-way intake valve through which drilling fluid is drawn from a supply tank and a one-way discharge valve through which drilling fluid is discharged to the well.
    Type: Grant
    Filed: May 10, 1983
    Date of Patent: July 9, 1985
    Assignee: Whiteman Manufacturing Company
    Inventor: Marvin E. Whiteman
  • Patent number: 4494912
    Abstract: An energy conserving air pump includes an air operating pump section and a separate fluid pumping section capable of handling pure fluids in concentrate form or in solution, and operates by the use of a single slug of air in the air operating section to shift a shuttle valve of differential diameter incorporated therein from a first to a second positions while simultaneously allowing air to actuate reciprocating pumping members incorporated into said fluid pumping section dispensing with complicated valves of conventional air pumps and allowing an automatic cycle repetition with the same air slug from a first pump atmospheric position which permits pump priming with suction of fluids pumped therethrough to a second pump discharge position, and vice-versa.
    Type: Grant
    Filed: September 16, 1982
    Date of Patent: January 22, 1985
    Inventor: Richard S. Pauliukonis
  • Patent number: 4269569
    Abstract: The present invention relates to a control system for automatic, continuous sequencing and modulating the flow rate of a plurality of high pressure pumps, having specific, albeit not exclusive application to mud pumps used in well drilling procedures.More particularly, the essence of the invention reposes in a novel volume output sensing servo system which continuously senses deviation in pump drive fluid volume output and automatically responds to such changes to maintain proper pump sequence.
    Type: Grant
    Filed: June 18, 1979
    Date of Patent: May 26, 1981
    Inventor: Francis W. Hoover
  • Patent number: 4213298
    Abstract: A self-reversing hydraulic control system for use with a device to be driven in opposite directional modes, especially a self-reversing pump driven by such a device. The system depends upon a flow sensing element disposed to sense flow associated with movement of the driven device and adapted to generate a stop signal responsive to the termination of such flow. A means responsive to the stop signal is then effective to shift the system from one directional mode to the other. Also featured is a sensor disposed to receive and transmit hydraulic fluid under pressure to drive the device, stoppage of the flow adapted to cause the sensor to shift position and to transmit pressurized hydraulic fluid pressure, as the stop signal via a hydraulic line. In preferred embodiments the self-reversing hydraulic control system has a two-position 4-way valve which is shifted in position by the hydraulic stop signal.
    Type: Grant
    Filed: July 3, 1978
    Date of Patent: July 22, 1980
    Assignee: Offshore Devices, Inc.
    Inventor: Jerome H. Milgram
  • Patent number: 4103490
    Abstract: An apparatus for harnessing and extracting a portion of the power generated by the rise and fall of ocean tides. A tidal chamber is provided wherein the rise of the tide creates positive air pressure within the tidal chamber and the fall of the tide creates a partial vacuum within the tidal chamber. The pressure and partial vacuum are, through appropriate valving, used to drive a pair of reciprocating, fluid-coupled rod and float assemblies, the motions of which can be harnessed to operate an air compressor, crank shaft, flywheel or other suitable mechanical device.
    Type: Grant
    Filed: March 28, 1977
    Date of Patent: August 1, 1978
    Inventor: Alexander Moiseevich Gorlov
  • Patent number: RE35473
    Abstract: A system for the transport of high solids sludge includes a positive displacement pump for pumping sludge through a pipeline. The volume of sludge transported is accurately measured by determining the fill percentage by using a material flow signal, measured time intervals, hydraulic fluid pressure, or hydraulic fluid flow rate during each pumping cycle.
    Type: Grant
    Filed: February 23, 1995
    Date of Patent: March 11, 1997
    Assignee: Schwing America, Inc.
    Inventors: Edward A. Oakley, Harry K. Crow, Thomas M. Anderson, Richard T. Atherton, Berthold A. Fehn