Means To Simultaneously Open Working Chambers To Inlet Or Exhaust Patents (Class 91/464)
  • Patent number: 8807013
    Abstract: Disclosed is a boom cylinder control circuit for a construction machine including a boom cylinder having an ascending-side chamber and a descending-side chamber. The boom cylinder control circuit includes: a first floating chamber with first and second input ports connected to the descending-side chamber and the ascending-side chamber, respectively, at one side, and first and second output ports connected with the drain tank, at the other side, and is switched to selectively connect the first and second input ports to the first and second output ports in accordance with an operational signal of the floating selection operation part; and a second floating valve of which one side is connected to the first output port and the other side is connected to the drain tank to selectively connect the first output port with the drain tank in accordance with the operational signal.
    Type: Grant
    Filed: November 2, 2009
    Date of Patent: August 19, 2014
    Assignee: Doosan Infracore Co., Ltd.
    Inventor: Won Sun Sohn
  • Patent number: 8671824
    Abstract: The invention relates to a hydraulic control arrangement for supplying a pressure medium to at least one consumer. The forward line and/or the return line of the consumer comprises a distributing valve that can be continuously controlled and that has two switch positions, and a lowering brake valve that can be placed in an open position due to the pressure in the supply line. The distributing valve is in an open neutral position and can be displaced, electrically or electrohydraulically, from said neutral position into the direction of the second switch position thereof.
    Type: Grant
    Filed: June 20, 2008
    Date of Patent: March 18, 2014
    Assignee: Robert Bosch GmbH
    Inventors: Wolfgang Kauss, Matthieu Desbois-Renaudin
  • Patent number: 8667886
    Abstract: Methods and apparatuses of generating a dynamic variable average flow applied by a hydraulic system of a vehicle.
    Type: Grant
    Filed: December 4, 2009
    Date of Patent: March 11, 2014
    Assignee: Deere and Company
    Inventors: Scott Svend Hendron, Robert Moore
  • Patent number: 8635940
    Abstract: A solenoid valve including a spool received within a housing. The spool is configured to move to multiple positions within the housing. The housing includes supply ports, exhaust ports, and outlet ports. When the spool is in a specific location, two outlet ports are in fluid communication with each other.
    Type: Grant
    Filed: January 7, 2008
    Date of Patent: January 28, 2014
    Assignee: Vanderbilt University
    Inventors: Michael Goldfarb, Xiangrong Shen
  • Patent number: 8001882
    Abstract: A double check valve having a floating function is disclosed, which can prevent construction equipment from overturning through intercepting of a floating function even if a signal pressure is fed to the double check valve to perform the floating function in a state that an excavator is supported by a working device (e.g. a dozer blade), i.e. in a jack-up state, on a sloping site and so on.
    Type: Grant
    Filed: September 10, 2008
    Date of Patent: August 23, 2011
    Assignee: Volvo Construction Equipment Holding Sweden AB
    Inventor: Tae In Hyang
  • Patent number: 7954420
    Abstract: The invention concerns a hydraulic valve arrangement (1) having at least two working connections (A, B), a check valve (5, 6) being allocated to each working connection (A, B), and a pressure relief valve (7, 8) being allocated to each check valve (5, 6), each pressure relief valve (7, 8) being connected to a control pressure passage (17, 18). The valve arrangement shall ensure a reliable, pressure-less lowering, also in connection with single-actuated consumers, and further enable a pressure-less float position. For this purpose, the check valves (5, 6) can be opened by means of tappets (20, 21), whose sides facing away from the check valves (5, 6) are ending in a pressure chamber (22), which is connected to the control pressure passage (17, 18) of one of the pressure relief valves (7, 8).
    Type: Grant
    Filed: July 9, 2008
    Date of Patent: June 7, 2011
    Assignee: Sauer-Danfoss Aps
    Inventors: Martin Raadkjaer Joergensen, Ken Petersen
  • Publication number: 20100224059
    Abstract: An electrohydraulic booster comprises an electromechanical transducer and a hydromechanical power stage which is connected to a pressurized medium supply and encompasses a cylinder and a piston that can be moved therein along the working axis. The electromechanical transducer acts on a spool valve which is associated with the hydromechanical power stage, is disposed at least in part inside the piston, is guided within a guiding bore in such a way as to be movable along the working axis, and has two first leading edges that cooperate with corresponding second leading edges located on the guiding bore in order to form a hydraulic sequential control. The guiding bore consists of two parts, i.e. a cylinder-mounted first section and a second section which can be moved along the working axis and comprises the second leading edges.
    Type: Application
    Filed: May 13, 2010
    Publication date: September 9, 2010
    Applicant: HOERBIGER AUTOMATISIERUNGSTECHNIK HOLDING GMBH
    Inventor: Manfred KURZ
  • Patent number: 7752842
    Abstract: Circuit for controlling a double-action hydraulic drive cylinder includes a directional control valve having working ports A and B, a pump port P, and a tank port T, wherein the directional control valve has a neutral position in which pump port P is blocked and working ports A, B are connected to tank port T. A pressure-limiting valve and a controllable load-holding valve are connected to the piston space in parallel, and a regeneration check valve is connected in series between a connection point for the parallel components and the rod space. A first precharge valve is connected between the working port A and the connection point, and a first bypass check valve is connected anti-parallel parallel with the first precharge valve and the load-holding valve. A second precharge valve is connected in series with the directional control valve between the tank port P and the rod space.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: July 13, 2010
    Assignee: Bucher Hydraulics AG
    Inventors: Ivan Hristov, Josef Zürcher
  • Patent number: 7603856
    Abstract: A heavy-construction machine (1) including a working implement (5) having one or a number of arms (6) articulated with regard to the chassis (2) of the machine. An assembly consisting of at least one hydraulic cylinder (7) that causes the working implement (5) to move relative to the chassis (2) is provided together with a hydraulic circuit that supplies these cylinders based on the control commands issued by a hydraulic manipulator. The machine is capable of operating according to two distinct modes of which one is a lifting mode and the other is a loading mode. In each mode, cylinder travel can be freed when the manipulator is in a predetermined position corresponding to a position referred to as floating control. The machine further includes a mechanism for rendering the floating control position of the manipulator inactive when the machine is operating in lifting mode.
    Type: Grant
    Filed: June 16, 2006
    Date of Patent: October 20, 2009
    Assignee: Volvo Construction Equipment AB
    Inventor: Gilles Florean
  • Patent number: 7472638
    Abstract: A fluid circuit is provided to independently control the flow of fluid into and out of each end of an actuator. This is accomplished by having two different independently controlled valves controlling the flow of fluid into and out of one end of the actuator and by having two other independently controlled valves controlling the flow of fluid into and out of the other end of the actuator. Regeneration of the fluid flow from one end of the actuator to the other end of the actuator is provided by blocking the exhaust flow of fluid to the reservoir by one of the independently controlled valves and redirecting the flow across the other of the independently controlled valves to join with the flow of the pump that is being directed to the other end of the actuator. This arrangement permits a portion or all of the fluid from one end of the actuator to be regenerated to the other end of the actuator.
    Type: Grant
    Filed: October 14, 2005
    Date of Patent: January 6, 2009
    Assignee: Caterpillar Inc.
    Inventors: Thomas J. Hajek, Jr., Vincent Triffaux
  • Patent number: 7305914
    Abstract: An actuator includes a piston within a cylinder, the cylinder having a first fluid port in communication with an open side of the piston, and a second fluid port in communication with a shaft side of the piston. The piston travels in a first direction, toward the shaft side of the piston and in a second direction, toward the open side of the piston. The actuator includes a valve circuit configured to selectively couple the first fluid port with a high-pressure fluid source when piston travel in the first direction is desired, and with a low-pressure fluid source when piston travel in the second direction is desired. The valve circuit is further configured to couple the second fluid port to the high-pressure fluid source when piston travel is desired in the first or second direction, and to close the first and second fluid ports when no piston travel is desired.
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: December 11, 2007
    Assignee: The United States of America, as represented by the Administrator of the Environmental Protection Agency
    Inventor: Charles L. Gray, Jr.
  • Patent number: 7302797
    Abstract: A hydraulic system for a work machine is disclosed. The hydraulic system has a reservoir configured to hold a supply of fluid and a source configured to pressurize the fluid. The hydraulic system also has a fluid actuator, a first valve, and a second valve. The first valve is configured to selectively fluidly communicate the source with the fluid actuator to facilitate movement of the fluid actuator in a first direction. The second valve is configured to selectively fluidly communicate the fluid actuator with the reservoir to facilitate movement of the fluid actuator in the first direction. The hydraulic system further has a proportional pressure compensating valve configured to control a pressure of a fluid directed between the fluid actuator and the reservoir.
    Type: Grant
    Filed: May 31, 2005
    Date of Patent: December 4, 2007
    Assignees: Caterpillar Inc., Shin Caterpillar Mitsubishi Ltd
    Inventors: Jiao Zhang, Pengfei Ma, Michael R. Schwab
  • Patent number: 7213612
    Abstract: A control valve for operating a fluid-actuated device includes a fluid inlet, a fluid outlet and a passage in fluid communication between the fluid inlet and the fluid outlet, the passage defining a longitudinal axis. A valve seat is disposed in the passage and includes an upstream diameter and a downstream diameter, the downstream diameter smaller than the upstream diameter. A ball poppet is positionable in a seated line contact position with the valve seat. The valve seat has a valve seat angle relative to a centerline of the longitudinal axis that is greater than an angle formed by the centerline and a line tangent to the ball poppet at the seated line contact position.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: May 8, 2007
    Assignee: Ross Operating Valve Company
    Inventor: Charles A. Weiler, Jr.
  • Patent number: 7080590
    Abstract: The invention concerns a valve arrangement for controlling a hydraulic drive having a first working connection (A) and a second working connection (B), and being connectable with or separable from a pressure source (P), the supply and the outflow of the hydraulic drive being separately controllable. It is endeavoured to improve the energetic efficiency of the valve arrangement. For this purpose, the first working connection (A) is connected with a first control valve and the second working connection (B) is connected with a second control valve, the first and the second control valves being connected with each other and with a third control valve, which is connected with a tank.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: July 25, 2006
    Assignee: Sauer-Danfoss ApS
    Inventors: Brian Nielsen, Poul Erik Hansen, Torben Ole Andersen
  • Patent number: 6997210
    Abstract: A valve arrangement including a release valve. The valve arrangement controls a cylinder assembly including a first port and a second port, and a cylinder slideably housing a piston for movement between an extended position and a retracted position. The valve arrangement includes a valve assembly in fluid communication with the source of fluid pressure and with the first port and the second port to control fluid flow between the source and the first port and second port, and a release valve fluidly connected to the first port and to the second port, the release valve being operable to control flow of fluid from the first port and from the second port. The release valve is movable between a closed position and an open position. Fluid flows from both the first port and the second port simultaneously when the release valve member is in the open position.
    Type: Grant
    Filed: July 19, 2002
    Date of Patent: February 14, 2006
    Assignee: Aladdin Engineering & Manufacturing, Inc.
    Inventors: Edward R. Horn, Robert E. Dowd, Thomas J. Thornton
  • Patent number: 6976418
    Abstract: A fluid circuit is provided to independently control the flow of fluid into and out of each end of an actuator. This is accomplished by having two different independently controlled valves controlling the flow of fluid into and out of one end of the actuator and by having two other independently controlled valves controlling the flow of fluid into and out of the other end of the actuator. Regeneration of the fluid flow from one end of the actuator to the other end of the actuator is provided by blocking the exhaust flow of fluid to the reservoir by one of the independently controlled valves and redirecting the flow across the other of the independently controlled valves to join with the flow of the pump that is being directed to the other end of the actuator. This arrangement permits a portion or all of the fluid from one end of the actuator to be regenerated to the other end of the actuator.
    Type: Grant
    Filed: January 5, 2004
    Date of Patent: December 20, 2005
    Assignee: Caterpillar Inc.
    Inventors: Thomas J. Hajek, Jr., Vincent Triffaux
  • Patent number: 6915730
    Abstract: A spool-type hydraulic directional control valve having improvements to reduce cavitation when the spool is in the float position. The flow area of a first passageway on the valve spool is appropriately sized to reduce the flow hydraulic fluid flow from the head end of the hydraulic cylinder to the hydraulic fluid reservoir, such that a sufficient proportion of that hydraulic fluid instead flows internally through control valve and back to the rod end of the hydraulic cylinder to reduce cavitation when the valve spool is in the “float” position. Additionally, a second passageway on the valve spool may be blocked-off, eliminating the hydraulic fluid flow path from the hydraulic fluid reservoir to the rod end of the hydraulic cylinder when the valve spool is in the “float” position.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: July 12, 2005
    Assignee: Deere & Company
    Inventor: Mark John Cherney
  • Patent number: 6886450
    Abstract: A piston/cylinder unit having a selectively inhibited movement includes a cylinder filled with a hydraulic medium and a piston arranged on a piston rod and dividing the cylinder into working spaces. A flow connection system having a flow connection is arranged between the first and second working spaces. The flow connection system includes an on-off valve having a movable valve element which opens the flow connection as a function of a position of the movable valve element. The flow connection system further includes a load-dependent valve arranged in series with the on-off valve for inhibiting complete flow through the flow connection independently from the on-off valve when a load on the piston/cylinder unit is lower than an inhibiting load.
    Type: Grant
    Filed: September 3, 2002
    Date of Patent: May 3, 2005
    Assignee: Stabilus GmbH
    Inventor: Axel Knopp
  • Patent number: 6802242
    Abstract: A pneumatic control system is provided for positioning a piston within a cylinder and comprises a positioner for regulating the flow of compressed air into and out of first and second ends of the cylinder. First and second large boosters force compressed air into the respective first and second ends. First and second small boosters and first and second quick exhaust valves collectively exhaust compressed air out of the respective first and second ends. First and second small and large booster check valves interposed between the directional valve and the respective first and second small and large boosters are oriented such that the flow of compressed air through the signal lines and into the first and second small and large boosters may be blocked for increasing the sensitivity of the positioning of the piston.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: October 12, 2004
    Assignee: Control Components, Inc.
    Inventors: Joseph Henry Steinke, Sanjay V. Sherikar
  • Patent number: 6691604
    Abstract: A fluid circuit is provided to independently control the flow of fluid into and out of each end of an actuator. This is accomplished by having two different independently controlled valves controlling the flow of fluid into and out of one end of the actuator and by having two other independently controlled valves controlling the flow of fluid into and out of the other end of the actuator. Regeneration of the fluid flow from one end of the actuator to the other end of the actuator is provided by blocking the exhaust flow of fluid to the reservoir by one of the independently controlled valves and redirecting the flow across the other of the independently controlled valves to join with the flow of the pump that is being directed to the other end of the actuator. This arrangement permits a portion or all of the fluid from one end of the actuator to be regenerated to the other end of the actuator.
    Type: Grant
    Filed: September 28, 1999
    Date of Patent: February 17, 2004
    Assignee: Caterpillar Inc
    Inventors: Thomas J. Hajek, Jr., Vincent Triffaux
  • Patent number: 6637461
    Abstract: A proportional hydraulic valve has a primary control spool with a force feedback actuator attached to one end, wherein the control spool meters flow of fluid to a work port. The force feedback actuator includes a piston coupled to the control spool and defining a first control chamber and a second control chamber on opposite sides of the piston. The surface of the piston has a depression with a first tapered section and a second tapered section. The force feedback actuator includes first electrohydraulic valve with a valve element that meters pressurized fluid selectively to the first and second control chambers to move the piston in opposite directions and produce motion of the control spool. A solenoid exerts a first force that on the valve element. A pilot pin engages the piston and the valve element, whereby, movement of the pilot pin on the first and second tapered sections of the piston applies a second force to the valve element.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: October 28, 2003
    Assignee: Husco International, Inc.
    Inventor: Timothy A. Post
  • Patent number: 6477937
    Abstract: A valve arrangement including a release valve. The valve arrangement controls a piston of a cylinder assembly upon interruption of a source of fluid pressure supplied to the cylinder assembly, the cylinder assembly including a first port and a second port and slideably housing the piston for movement between an extended position and a retracted position. The valve arrangement includes a valve assembly in fluid communication with the source of fluid pressure and with the first port and the second port to control fluid flow between the source of fluid pressure on the first port and between the source of fluid pressure on the second port, and a release valve fluidly connected to the first port and to the second port, the release valve being operable to control flow of fluid from the first port and from the second port.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: November 12, 2002
    Assignee: Aladdin Engineering & Manufacturing
    Inventors: Edward R. Horn, Robert E. Dowd
  • Patent number: 6477835
    Abstract: An improved device (10) for moving a load (11) rotationally and/or axially relative to a body (12) broadly comprises: a body; a motor (13) mounted on the body and having an output shaft (14) operatively arranged to move the load rotationally relative to the body; a piston (16) movably mounted on the body and defining therewith a variable volume first chamber (19), the piston being operatively arranged to move the load axially relative to the body; an accumulator (23) charged to a predetermined pressure; a fluid in the first chamber and accumulator; a pump (26) driven by the motor, the pump being operatively arranged to displace fluid from the first chamber to the accumulator; and a valve (28) operatively arranged to selectively permit pressurized fluid in the accumulator to flow into the first chamber to move the piston and load in one direction axially relative to the body.
    Type: Grant
    Filed: August 29, 2001
    Date of Patent: November 12, 2002
    Assignee: Moog Inc.
    Inventor: David Geiger
  • Patent number: 6457487
    Abstract: An assembly of a pair of electrically operated bidirectional proportional control valves and a four-way direction control valve governs the flow of fluid to and from a hydraulic cylinder. The four-way direction control valve alternately connects a pump supply line to one of a pair of intermediate conduits and a tank return line to the other intermediate conduit. That connection determines the direction of movement of the cylinder piston. The intermediate conduits are coupled to chambers of the cylinder by a separate one of the proportional control valves which meters the fluid flow to or from the respective chamber. Thus the proportional control valves control the rate of piston movement.
    Type: Grant
    Filed: May 2, 2001
    Date of Patent: October 1, 2002
    Assignee: Husco International, Inc.
    Inventors: Dwight B. Stephenson, Joseph Lawrence Pfaff
  • Patent number: 6431209
    Abstract: A high-pressure primary fluid control valve and a multi-pressure selector fluid control valve are disclosed for operating a fluid-actuated device. Preferably a spherical ball-poppet and frusto-conical valve seat adapted for substantially line-contact therebetween are provided with an upstream flow area adjacent the line-contact in order to substantially minimize sonic flow damage to the actual sealing surface of the valve seat by shifting it away from such line-contact seating. Preferably, the ball-poppet is movable within a poppet guide that is allowed to float radially in order to allow the ball-poppet to be substantially self-centering with respect to the valve seat. In addition, cross-over leakage is preferably negated by closing an exhaust ball-poppet just prior to opening a supply ball-poppet. These principles and features are equally applicable to either or both of the primary or the multi-pressure selector fluid control valves.
    Type: Grant
    Filed: September 27, 2000
    Date of Patent: August 13, 2002
    Assignee: Ross Operating Valve Company
    Inventor: Charles A. Weiler, Jr.
  • Patent number: 6431207
    Abstract: A high-pressure fluid control valve is disclosed for operating a fluid-actuated device. Preferably a ball-poppet and frusto-conical valve seat adapted for substantially line-type contact therebetween are provided with an upstream restricted flow area in order to substantially minimize sonic flow damage to the actual sealing surface of the valve seat. Preferably, the ball-poppet is movable within a poppet guide that is allowed to float radially in order to allow the ball-poppet to be substantially self-centering with respect to the valve seat. In addition, cross-over leakage is preferably negated by closing an exhaust ball-poppet just prior to opening a supply ball-poppet.
    Type: Grant
    Filed: March 16, 2000
    Date of Patent: August 13, 2002
    Assignee: Ross Operating Valve Company
    Inventor: Charles A. Weiler, Jr.
  • Patent number: 6408877
    Abstract: The valve comprises a slider-valving member having two lateral valving elements (22, 22A, 22B) positioned on one and the other side of the transverse central plane, they being subjected to the direct action of thrust means (15) and movable axially between a first operative position defining said normal configuration of the slider-valving member (20, 20A, 20B), and a second operative position in which a further different communication condition between the channels is determined; spring means (23, 35, 45) are also provided, arranged to normally maintain the two lateral valving elements (22, 22A, 22B) in said first operative position.
    Type: Grant
    Filed: December 12, 2000
    Date of Patent: June 25, 2002
    Assignee: Bucher Hidroirma S.p.A.
    Inventors: Mario Venditti, Luca Ibatici
  • Patent number: 6354185
    Abstract: A fluid control module that can control the flow of fluid between a rail line, a drain line, a first cylinder line and a second cylinder line. The control module includes a plurality of fluid-driven valves that can couple the cylinder lines to the rail and drain lines. Each fluid-driven valve is controlled by a control valve. The module may be actuated into one of a plurality of different states.
    Type: Grant
    Filed: June 17, 1999
    Date of Patent: March 12, 2002
    Assignee: Sturman Industries, Inc.
    Inventor: Oded E. Sturman
  • Patent number: 6293181
    Abstract: A control system is provided with a float condition to permit a double acting hydraulic cylinder to freely extend or retract in response to external forces acting on the hydraulic cylinder. The system includes a pair of pilot operated poppet valves disposed between the opposite sides of the hydraulic cylinder and a directional control valve. The pilot condition is obtained by opening a pair of pilot operated control valves to vent the control chambers of the poppet valves to a tank through a pair of float check valves. The float check valves are operative to prevent higher pressure fluid from being transmitted from the tank to the control chambers of the poppet valves when a negative pressure occurs in the side of the hydraulic cylinder that is connected to the control chamber.
    Type: Grant
    Filed: September 21, 1999
    Date of Patent: September 25, 2001
    Assignee: Caterpillar Inc.
    Inventors: Thomas J. Hajek, Jr., Srikrishnan T. Tolappa, Daniel T. Mather
  • Patent number: 6202536
    Abstract: In a pneumatic reciprocating actuator of the kind comprising a cylinder which defines a forward-motion chamber and a return-motion chamber, and a piston which is reciprocal in the cylinder and separates the forward-motion chamber and the return-motion chamber, a start stroke forwardly is initiated by admission of gaseous operating fluid from an inlet port in to the foreword-motion chamber with both the forward-motion chamber and the return-motion chamber initially at zero pressure. The operating fluid is also passed from the inlet port into the return-motion chamber during the start stroke until a back pressure of a predetermined magnitude has been produced in the return-motion chamber. Then the return-motion chamber is automatically closed by a pressure control valve unit, whereby the return-motion chamber will form a cushioning chamber for cushioning the movement of the piston in the forward direction, thereby preventing piston over speeding during the start stroke.
    Type: Grant
    Filed: July 13, 1999
    Date of Patent: March 20, 2001
    Assignee: Pos-Line AB
    Inventor: Bert Harju
  • Patent number: 6095028
    Abstract: The invention relates to a hydraulic unit for feeding an object at a desired feed speed a distance in a given feed direction during a working stroke and, in a return stroke, bringing the object back to the initial position at a considerably greater return speed, comprising a double-acting working cylinder (1) with a piston (16), the piston rod (17) of which is connected to the object which is to be moved, and a receiver cylinder (2) which is provided with a second piston (28) and designed to be filled with oil from the working cylinder during the return stroke, the first piston (16) and the second piston (28) being interconnected by a rigid connecting member (31) which forces the second piston to follow the movements of the first piston.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: August 1, 2000
    Assignee: Kvaerner Pulping AB
    Inventors: Axel Stig Lam.ang.s, Allan Sven Jonsson
  • Patent number: 6092454
    Abstract: A controlled float circuit is provided for controlling a load free of requiring flow from the source of pressurized fluid even when the float mode is activated with the load above the ground. The subject invention includes having a load lowering check valve arrangement disposed adjacent an actuator having first and second inlet ports with a pilot operated check valve disposed between the second inlet port and a location downstream of the load lowering valve. A first normally open electrically controlled valve is disposed in the pilot conduit leading to one end of a directional control valve and a second normally closed electrically controlled valve disposed between a source of pressurized pilot fluid and the pilot stage of the pilot operated check valve. Engagement of the float mode of operation blocks pilot flow to one end of the directional valve and opens the pilot operated check valve.
    Type: Grant
    Filed: June 1, 1999
    Date of Patent: July 25, 2000
    Assignee: Caterpillar Inc.
    Inventor: Philippe G. Vande Kerckhove
  • Patent number: 5964406
    Abstract: A hydraulically-actuated fuel injector includes an injector body that defines a high pressure inlet, a low pressure drain, an upper actuation fluid cavity, a lower actuation fluid cavity, and a nozzle outlet. A piston is positioned in the injector body and moveable between a retracted position and an advanced position. A control valve is attached in the injector body and includes a spool valve member that is moveable between a first position and a second position. When the spool valve member is in its first position, the piston is biased toward its retracted position since the upper actuation fluid cavity is open to the low pressure drain, but the lower actuation fluid cavity is open to the high pressure inlet. During an injection event, the spool valve member is moved to its second position where the upper actuation fluid cavity is open to the high pressure inlet, but the lower actuation fluid cavity is open to the low pressure drain.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: October 12, 1999
    Assignee: Caterpillar Inc.
    Inventor: Lianghe Zuo
  • Patent number: 5921279
    Abstract: A proportional hydraulic control valve assembly has a pair of bores in a valve body with separate control spools in each bore. A pair of force feedback, linear actuators are mounted on the same side of the valve body and each actuator controls the movement of a different one of the control spools. Only one of the control spools governs application of hydraulic power to a first work port of the valve assembly, while connecting a second work port to tank. Only the other control spool governs application of hydraulic power to the second work port of the valve assembly, while connecting a first work port to tank. The force feedback, linear actuators enable each spool to be received very tightly within the respective bore.
    Type: Grant
    Filed: April 29, 1998
    Date of Patent: July 13, 1999
    Assignee: HUSCO International, Inc.
    Inventor: Dennis R. Barber
  • Patent number: 5918631
    Abstract: A pneumatic fluid control valve includes a valve body having a fluid inlet connectable to an external source of pressurized pneumatic working fluid, one or more load outlets, one or more corresponding exhaust ports, and a movable valve mechanism. The movable valve mechanism includes at least a pair of movable valve element and preferably resilient deformable connectors in a generally abutting relationship between adjacent movable valve elements for deformably transmitting coordinated motion therebetween. The deformable connector resiliently allows one of the movable elements to move and compress the connector before such coordinated motion is transmitted to the other movable element in order to minimize internal leakage.
    Type: Grant
    Filed: April 14, 1998
    Date of Patent: July 6, 1999
    Assignee: Ross Operating Valve Company
    Inventors: Charles A. Weiler, Jr., Paul G. Storrs
  • Patent number: 5816131
    Abstract: A fluid-controlled actuator assembly for a gearbox of a vehicle. The actuator is provided with a four-position mobile element, with a first and a second chamber separated in a sealed manner from the mobile element, and with auxiliary positioning elements suitable for determining a stop position of the mobile element. Also included are first and second solenoid valves suitable for supplying pressurized fluid respectively to the first and to the second chamber and for discharging it from them, such that when the fluid is supplied into both the chambers, the mobile element is maintained by the auxiliary positioning elements in the stop position. When the fluid is supplied into one of the chambers and is discharged from the other, the mobile element adopts one of two lateral positions with respect to the stop position.
    Type: Grant
    Filed: April 25, 1997
    Date of Patent: October 6, 1998
    Assignee: Magneti Marelli S.p.A.
    Inventor: Giovanni Tornatore
  • Patent number: 5765594
    Abstract: A hydraulic control valve for controlling flow between a pump, a hydraulic device, and a vessel containing hydraulic fluid. The control valve has an elongated valve slide which is slidably mounted in an elongated valve housing. The valve has three positions, a central neutral position, a float position axially offset in one direction from the neutral position and a constant pressure position axially offset in the opposite direction from the neutral position. In the neutral position, flow of hydraulic fluid to the hydraulic device is inhibited. In the float position, connection is such that a raised device, such as a hydraulically operated bucket, is lowered slowly by gravity until it rests on the ground or another object. In the constant pressure position, the valve connects pump pressure to the load sensing circuit to facilitate, for example, shaking of a bucket of a piece of earth moving equipment.
    Type: Grant
    Filed: April 2, 1996
    Date of Patent: June 16, 1998
    Assignee: Danfoss A/S
    Inventors: David Collins, Helge Joergensen, Xavier Mabit, Carsten Christensen
  • Patent number: 5644967
    Abstract: A servo valve arrangement with a high-pressure, low-pressure and motor connection and with a pressure control valve arranged between the high-pressure connection and motor connection and a return control valve arranged between the motor connection and low-pressure connection is provided. The pressure control valve normally is closed and the return control valve normally is open. The pressure control valve can be opened by a common actuating member whilst closing the return control valve. The valve arrangement is suitable, in particular, for hydraulic power steering systems of motor vehicles with a so-called closed center.
    Type: Grant
    Filed: June 28, 1995
    Date of Patent: July 8, 1997
    Assignee: Mercedes-Benz AG
    Inventors: Wolfgang Joerg, Jaromir Bordovsky, Aydogan Cakmaz, Hubert Heck, Arno Roehringer, Claus Gall, Reinhold Abt, Rainer Strauss, Karl-Hans Koehler
  • Patent number: 5606901
    Abstract: A turning-purpose hydraulic circuit characterized in that a discharge passage (20a) of a hydraulic pump (20) is connected to a variable relief valve (21) and a pump port of a directional switching valve (22); a first actuator port and a second actuator port (25, 26) of the said directional switching valve are connected to a turning-purpose hydraulic motor (27); the pilot pressure of a pilot valve (33) is introduced into pressure chambers (31, 32) for controlling a spool in the said directional switching valve and is also introduced into a pressure chamber (40) for controlling a set pressure in the said variable relief valve; a metering-in side portion (42) along which a pressurized oil flows from the said pump port of the said spool to the first or second actuator port is formed with a portion having a configuration such that a flow force may not be produced thereat; and a metering-out side portion (45) along which the pressurized oil flows from the first or second actuator port of the said spool to a tank po
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: March 4, 1997
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Isao Oki
  • Patent number: 5586480
    Abstract: A pneumatic motor including a motor body having a piston chamber with opposed chamber ends, at least two valve chambers, an inlet for flowing a pressurized fluid into the piston chamber and each of the at least two valve chambers, a number of outlets provided in the housing for exhausting the pressurized fluid from the piston chamber and each of the at least two valve chambers. The motor also includes a three-way valve member adapted to be located in each of the at least two valve chambers, the valve members each have at least one open end and at least one port formed along the valve member body. A spool member is located in one of the valve chambers, each spool member has a first end adapted to be located in the open end of the valve member.
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: December 24, 1996
    Assignee: Ingersoll-Rand Company
    Inventor: Richard K. Gardner
  • Patent number: 5546847
    Abstract: A hydraulic cylinder snubbing arrangement includes a pilot operated control valve having a predetermined snubbing position at which flow exhausted from a hydraulic cylinder actuating chamber must pass through a plurality of flow restricting orifices in a valve spool when the hydraulic cylinder is retracted to a predetermined position. The valve spool is shifted to the snubbing position automatically by reducing the fluid pressure in a pilot chamber at the end of the valve spool to a predetermined level so that a snubber spring device resiliently moves the spool from a lower or float position. By forcing the fluid to pass through the restricted flow path created by the orifices, the gravity induced velocity of the hydraulic cylinder is greatly reduced as the hydraulic cylinder approaches its end of stroke position.
    Type: Grant
    Filed: September 12, 1995
    Date of Patent: August 20, 1996
    Assignee: Caterpillar Inc.
    Inventors: Charles E. Rector, Steven R. Wells, Daniel T. Mather, Robin S. Arndt
  • Patent number: 5391041
    Abstract: A mechanism is provided for deploying a wheelchair ramp at the door of a vehicle, especially a bus, the ramp being of the kind which rotates between a stowed position at which it is flush with the vehicle floor and a deployed position in which it slopes downwardly and outwardly from the vehicle. The mechanism provides a "float down" feature which permits the ramp to move downward under gravity without the need for operator control and prevents crushing of obstacles that get in the downward path of the ramp. The mechanism includes a transmission for translating a single hydraulic cylinder stroke into more than 180.degree. of rotation of the ramp.
    Type: Grant
    Filed: January 6, 1993
    Date of Patent: February 21, 1995
    Assignee: New Flyer Industries Limited
    Inventors: David A. Stanbury, Glenn M. Campbell, Philip J. Fleury
  • Patent number: 5353686
    Abstract: A hydraulic circuit, having a four-position closed-center valve (6) controlled by a proportional control valve (22), can facilitate the vertical position control and operating speed control of a blade with a simple structure, while providing that the floating condition of the blade can be precisely recognized by the position of a control lever (20a). The spool (41) of the four-position selector valve (6) has a "hold" position which is given by the closed-center position. Opposite ends of the spool (41) receive a pilot pressure from the pressure proportional control valve (22), one position being obtained by applying pilot pressure to a first end of the spool (41), and two positions being obtained by applying pilot pressure to the second end of the spool (41). One of the latter two positions is a "floating" position, while the other two positions are the "up" position and the "down" position.
    Type: Grant
    Filed: May 25, 1993
    Date of Patent: October 11, 1994
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Mitsuaki Nakamura
  • Patent number: 5341572
    Abstract: A hydraulic tool, such as might be used to prune trees, for alternately producing a relatively strong power stroke and a relatively weak reset stroke, which includes a reciprocating member within a housing and a hydraulic system made up of two chambers. The first chamber has an effective projected area relative to the reciprocating member and is hydraulically connected to the outlet. The second chamber has an effective projected area relative to the reciprocating member which is smaller than that of the first chamber. The second chamber is hydraulically connected to the inlet only during the power stroke, and is hydraulically connected to the first chamber only during the reset stroke and during the time between the end of the reset stroke and the beginning of the next power stroke.
    Type: Grant
    Filed: March 11, 1993
    Date of Patent: August 30, 1994
    Inventor: Yigal Michelson
  • Patent number: 5235896
    Abstract: In a position independent locking of a hydraulic cylinder/piston mechanism, a pressure limiting member is provided in the supply pipe for the hydraulic medium, with the pressure limiting member being open during the hydraulic displacement of the piston and is closed during lack of hydraulic pressure. The pressure limiting member opens starting from a specific pressurization of the hydraulic medium as a result of a force generated by means of the piston and is located in a related working chamber.
    Type: Grant
    Filed: March 18, 1992
    Date of Patent: August 17, 1993
    Assignee: Hoerbiger Fluidtechnik GmbH
    Inventor: Gerhard Huber
  • Patent number: 5211196
    Abstract: A proportional valve comprises two electrically actuated proportional throttle valves, each having an outlet connected to a non-return valve, to each of which a seat valve is connected, each seat valve being pilot-controlled by one of the proportional throttle valves; the electric actuation of the proportional throttle valves proportionally controls and regulates the functions of a hydraulic cylinder. The two throttle valves and the two seat valves are mounted on a housing block which has a planar face at which are connections to a pressure line, a tank line and working lines.
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: May 18, 1993
    Assignee: Hydrolux S.A.R.L.
    Inventor: Hans Schwelm
  • Patent number: 5207059
    Abstract: Hydraulic control systems are useful for controlling actuation of hydraulic motors. Some such systems use spool type valves while other systems use poppet type valves, both of which have their advantages and disadvantages. The present hydraulic control system is a hybrid system utilizing a combination of both a spool type control valve and poppet type control valves in a single work circuit. Specifically, a spool type control valve has an inlet port connected to a variable displacement pump and a pair of flow amplifying poppet type valves are serially disposed between a pair of motor ports of the spool type valve and a pair of actuating chambers of a double acting hydraulic motor. The spool type control valve is operative to control pump-to-motor flow while one of the poppet type valves is operative to control motor-to-tank flow.
    Type: Grant
    Filed: January 15, 1992
    Date of Patent: May 4, 1993
    Assignee: Caterpillar Inc.
    Inventor: Lawrence F. Schexnayder
  • Patent number: 5174189
    Abstract: A fluid control apparatus which communicates a fluid cylinder with a fluid supply passage and a return passage, and a piston of the fluid cylinder is connected to a spoiler of an airplane.The fluid control apparatus comprises a hydraulic passage and a check valve. The hydraulic passage is capable of communicating with cylinder chambers located at both sides of the piston. The check valve is opened by hydraulic pressure generated by backward movement of the piston.The fluid control apparatus has a blow down valve characteristic so that the piston is allowed to move only in one direction by an external force when supply of fluid to the actuator is stopped because at least one of the supply passage and the return passage is damaged.The fluid control apparatus further has a retainer and a manually operable member.The retainer communicates the return passage with the hydraulic passage capable of communicating with cylinder chambers of the actuator.
    Type: Grant
    Filed: October 16, 1991
    Date of Patent: December 29, 1992
    Assignee: Teijin Seiki Co., Ltd.
    Inventor: Toshio Kamimura
  • Patent number: 5074335
    Abstract: A directional control valve is provided which can be switched into one of its switching positions only after the operator has supplied an additional signal.
    Type: Grant
    Filed: August 3, 1990
    Date of Patent: December 24, 1991
    Assignee: Mannesmann Rexroth GmbH
    Inventor: Herbert Beuermann
  • Patent number: 5067519
    Abstract: An improved safety valve includes piston-actuated provisions for gradually pressurizing a fluid-actuated motor during start-up of the system, preferably by way of a changeable flow restriction. In addition such improved safety valve preferably includes a floating exhaust valve actuating apparatus movable in an exhaust closure chamber and that operates in response to the presence or absence of line pressure in the exhaust closure chamber for respectively blocking off or opening fluid communication between the safety valve's outlet port and exhaust port. A pilot operator is also included for selectively permitting or cutting off line pressure flow to actuate the piston actuator and the exhaust valve actuating apparatus. The preferred safety valve also includes a check valve for preventing back-flow from the safety valve's outlet port back to the piston actuator and back to the exhaust valve actuating apparatus.
    Type: Grant
    Filed: November 26, 1990
    Date of Patent: November 26, 1991
    Assignee: Ross Operating Valve Company
    Inventors: Neil E. Russell, Owen H. Libby