Pilot Valve (304) Patents (Class 91/461)
  • Patent number: 10352318
    Abstract: A hydraulic regulating device includes a continuously adjustable regulating valve with a control piston. The control piston is displaceable in a first direction in which a connection of a pump port to an actuating-pressure port is configured to be controlled to open. The control piston is also displaceable in a second direction in which a connection of the actuating-pressure port to a tank port is configured to be controlled to open. In the first direction, the pump pressure acts on the control piston, and in the second direction, a control pressure and a spring act on the control piston. During movement of the control piston in the first direction, a damping connection, equipped with a damping nozzle, from the pump port to the tank port is configured to be controlled to open.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: July 16, 2019
    Assignee: Robert Bosch GmbH
    Inventors: Andreas Utler, Ralf Joechle, Rolf Wiefel, Steffen Raschendorfer
  • Patent number: 9790661
    Abstract: A hydraulic system for a machine is disclosed. The hydraulic system may have a tank configured to hold a supply of fluid, a pump configured to draw fluid from the tank and pressurize the fluid, a first cylinder operatively connected between a first side of a work tool and an undercarriage of the machine, and a second cylinder operatively connected between a second side of the work tool and the undercarriage of the machine. The hydraulic system may also have a first electro-hydraulic valve associated with the first cylinder and configured to selectively regulate a flow of pressurized fluid to the first cylinder independently of the second cylinder, and a second electro-hydraulic valve associated with the second cylinder and configured to selectively regulate a flow of pressurized fluid to the second cylinder independently of the first cylinder.
    Type: Grant
    Filed: November 24, 2014
    Date of Patent: October 17, 2017
    Assignee: Caterpillar Inc.
    Inventors: Timothy L. Hand, Heather Armistead, Fuaad Sayeed, Srikalyan C. Puranam, Stephen Garnett
  • Patent number: 9470246
    Abstract: A hydraulic system for a loader backhoe work machine in which a propulsion system has a limited output and the pressure relief for the hydraulic actuation system is at a first level for the loader function in which the machine is moved on the ground and a second higher pressure relief for when the backhoe function is being performed.
    Type: Grant
    Filed: June 5, 2015
    Date of Patent: October 18, 2016
    Assignee: CNH Industrial America LLC
    Inventors: Charles D. Anderson, David J. Sanning
  • Patent number: 9328757
    Abstract: Provided is a hydraulic system for a work machine, which can ensure low temperature responsiveness of remote control valves that perform pilot operations of pilot operated directional control valves for controlling hydraulic actuators, respectively. In order to, with bringing an unloading valve V13 to an unloading position 29, circulate oil to a pilot pump oil passage w that supplies the pressure oil from the discharging circuit Y for a pilot pump 19 to remote control valves PV1, PV2, and PV6, a warm-up circuit H that flows the oil from the discharging circuit Y for the pilot pump 19 to a terminal of the pilot pump oil passage w is provided.
    Type: Grant
    Filed: August 21, 2012
    Date of Patent: May 3, 2016
    Assignee: KUBOTA CORPORATION
    Inventor: Hiroshi Horii
  • Patent number: 9297462
    Abstract: A switch valve which is configured such that a plurality of land sections and a valley section between the land sections are formed in a valve element that advances or retreats in an axial direction according to a manual operation, a plurality of port sections opened are provided in a cylinder section in which the valve element is inserted so as to be capable of advancing and retreating, and the prescribed port sections are made to communicate with each other via the valley section according to a position of the valve element in the axial direction or be blocked by the land section, the switch valve includes a seal section that seals a space between portions on both sides in the axial direction across either one of the land sections in a liquid-tight manner.
    Type: Grant
    Filed: August 3, 2011
    Date of Patent: March 29, 2016
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Yuji Hattori, Tomokazu Inagawa, Kenta Kimura, Takafumi Inagaki, Yu Nagasato
  • Patent number: 9217376
    Abstract: A gas turbine engine control system according to an exemplary aspect of the present disclosure includes, among other things, an automatic control operable to control a gas turbine engine. The gas turbine engine control system further comprises a module operable to fail-fix the gas turbine engine to one of a multiple of pre-determined modes in response to failure of the automatic control. The exemplary gas turbine engine control system may further comprise a fuel flow meter to sense a fuel flow to the engine, a fuel control to control the fuel flow to the engine, and the module in electrical communication with the fuel flow meter to fix the fuel control in response to one of the multiple of pre-determined modes.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: December 22, 2015
    Assignee: Sikorsky Aircraft Corporation
    Inventors: David H. Sweet, Stephen H. Silder
  • Patent number: 8972124
    Abstract: A work vehicle includes an engine, an idling stop execution portion, a determination portion, a counting portion, and an idling stop time period adjustment portion. The engine can rotate in a first idling state and a second idling state in which the engine rotates at the number of rotations higher than a prescribed number of rotations. The idling stop execution portion performs an idling stop operation for stopping the engine. The determination portion determines whether or not stop has been made from the second idling state. The counting portion counts the number of times of stop of the engine from the second idling state. An idling stop time period adjustment portion makes a prescribed time period of the second idling state longer than a current time period, when the number of times of stop of the engine is equal to or greater than the prescribed number of times.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: March 3, 2015
    Assignee: Komatsu Ltd.
    Inventors: Tadashi Mori, Jin Yogita
  • Patent number: 8925584
    Abstract: A hydraulic pilot control arrangement for a spool valve is provided, wherein the spool of the spool valve is biased towards a central position. The arrangement includes a first and a second pilot hydraulic line connected to opposite sides of the spool of the spool valve and a pilot pressure regulating arrangement is provided for selectively establishing or removing a pilot pressure in each of the first and second lines. The arrangement includes a damping device including a chamber divided into a first and a second pressure compartment by a sliding piston, the first and second pressure compartments being connected respectively to the first and second pilot hydraulic lines, and the piston is biased towards a rest position in the chamber.
    Type: Grant
    Filed: October 26, 2009
    Date of Patent: January 6, 2015
    Assignee: Renault Trucks
    Inventors: Christian Balmonet, David Lazzaro
  • Patent number: 8844291
    Abstract: A universal heat engine is disclosed for converting energy from an input heat source to an output. The universal heat engine comprises a heat engine section and an output section. The heat engine section includes a heat engine bore receiving a heat engine piston. A heat engine valve assembly communicates with the heat engine bore for effecting reciprocal motion of the heat engine piston. The output section includes an output bore receiving an output piston. A piston rod interconnects the heat engine piston to the output piston. A control controls the heat engine valve assemblies to operate the heat engine section in accordance with a desired output from the output section. The heat source may comprise the burning of a petroleum product, a solar heat source, geothermal heat source or a byproduct heat source. The output may comprise a static or mobile air conditioning system or an electrical generator.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: September 30, 2014
    Assignee: VaporGenics Inc.
    Inventors: Eric M Gilmore, Michael B Gilmore, Patrick Sheppard, James M Berry, Timothy K. Mariani
  • Patent number: 8833065
    Abstract: A control device for a hybrid construction machine includes a discharge pressure introduction passage that leads a discharge pressure from a variable volume pump to a regulator, and a load pressure introduction passage that leads one of a maximum load pressure of respective actuators and a load pressure of a hydraulic motor to the regulator. A controller, having determined that the actuators are in an inoperative condition on the basis of a detection result from an operating condition detector, excites a solenoid of a solenoid pilot control valve such that a discharge oil from the variable volume pump is led to the hydraulic motor, and controls the regulator such that a differential pressure between the discharge pressure of the variable volume pump and the load pressure of the hydraulic motor is kept constant.
    Type: Grant
    Filed: July 2, 2010
    Date of Patent: September 16, 2014
    Assignee: Kayaba Industry Co., Ltd.
    Inventors: Haruhiko Kawasaki, Masahiro Egawa
  • Patent number: 8833068
    Abstract: A lock valve switching section switches a lock valve from a locked state to a released state when a lock member is switched from a locked position to a release position. An erroneous operation monitoring section maintains the lock valve in the released state when the pilot pressure is equal to or more than a predetermined pressure when elapsed time, which is from a point in time where the lock member is switched from the locked position to the release position, is equal to or more than the predetermined time. The erroneous operation monitoring section switches the lock valve to the locked state when the pilot pressure is equal to or more than the predetermined pressure when the elapsed time is less than the predetermined time.
    Type: Grant
    Filed: December 6, 2012
    Date of Patent: September 16, 2014
    Assignee: Komatsu Ltd.
    Inventors: Manabu Himoto, Daisuke Tsumura, Yoshimasa Ohbora, Jin Yogita
  • Patent number: 8806863
    Abstract: A hydraulic transmission unit comprises at least one pressure regulation valve (1) and a pilot control valve (2) which is connected to the pressure regulation valve (1) by a pilot control line (35). A pre-filling valve (3, 303) sets a pre-filling pressure (p—3) to avoid draining of a clutch (20) and the lines (231, 331) connected to the clutch (20) in an operating condition in which the clutch (20) is not actuated. To avoid draining when the clutch when in the operating condition, the pilot control line (35) is also connected to at least one line (236, 238, 336, 338) which is pressurized with a second pre-filling pressure (p—3).
    Type: Grant
    Filed: March 25, 2010
    Date of Patent: August 19, 2014
    Assignee: ZF Friedrichshafen AG
    Inventors: Georg Gierer, Thilo Schmidt, Christian Popp
  • Publication number: 20140174071
    Abstract: The present invention relates to a hydraulic control system for construction machinery capable of variably adjusting a set pressure of a relief valve, which controls a set pressure of a hydraulic system, according to a value inputted by means of pressure in the hydraulic system or the manipulation of a joystick.
    Type: Application
    Filed: August 9, 2011
    Publication date: June 26, 2014
    Applicant: VOLVO CONSTRUCTION EQUIPMENT AB
    Inventor: Chun-Han Lee
  • Patent number: 8683720
    Abstract: The present disclosure provides a hitch suspension system that reduces a transfer of energy (e.g., provides a smoother ride) between two bodies hitched together, such as between a towing vehicle and a towed vehicle/trailer. In an embodiment, the suspension system includes a hydraulic cylinder with an extendable rod in fluid communication with a fluid pump. A control valve is fluidly coupled between the hydraulic cylinder and the fluid pump and is configured to adjust an extension length of the rod. Additionally, a variable orifice that adjusts resistance to extension and retraction of the rod is fluidly coupled between the hydraulic cylinder and the control valve. A first fixed restrictive element is fluidly coupled in series with the variable orifice to dissipate energy ad the rod extends and a second fixed restrictive element is fluidly coupled in series with the variable orifice to dissipate energy as the rod retracts.
    Type: Grant
    Filed: June 27, 2011
    Date of Patent: April 1, 2014
    Assignee: Caterpillar Inc.
    Inventors: David E. Ault, Jeffrey L. Kuehn
  • Patent number: 8684037
    Abstract: A poppet valve assembly includes a body having a first axial end portion and a second axial end portion. The first axial end portion includes a tapered surface adapted for sealing engagement with a valve seat. The second axial end portion defines a metering orifice. The body defines a passage that includes an opening in the first axial end portion and is in fluid communication with the metering orifice. The passage includes a check valve seat. A check valve is disposed in the passage. The check valve is adapted to sealingly engage the check valve seat.
    Type: Grant
    Filed: August 5, 2009
    Date of Patent: April 1, 2014
    Assignee: Eaton Corportion
    Inventor: Tam C. Huynh
  • Patent number: 8656711
    Abstract: A hydraulic circuit for operating a tool is provided that is particularly useful in construction equipment such as an excavator, crane, wheel loader, drilling machine, or others. Furthermore, a control unit and a method for controlling the hydraulic circuit and construction equipment including such a hydraulic circuit is disclosed.
    Type: Grant
    Filed: February 6, 2007
    Date of Patent: February 25, 2014
    Assignee: Volvo Construction Equipment AB
    Inventors: Alfred Richter, Frederic Lastre
  • Patent number: 8578837
    Abstract: The pressure in the downstream side of a pneumatic cylinder's piston (1g) is allowed to exhaust. At a certain point, the downstream exhaust is blocked, causing the pressure to rise against the downstream side of the piston. A valve (5) opens when the downstream chamber has reached its maximum pressure. The output of valve (5) opens a second valve (3). Valve (3) rapidly exhausts the remaining air on the downstream side of the piston (1p). With no air on the downstream side of piston (1p), piston (1p) stops and does not bounce back. Changing the volume of inactive regions (1m) or (1n) sets the stopping point to coincide with the end of stroke of piston (1p). A check valve (4) and orifice (6a) allow the air in the pilot port in valve (3) to slowly bleed out, resetting valve (3) for the next cycle.
    Type: Grant
    Filed: May 12, 2010
    Date of Patent: November 12, 2013
    Inventor: John C. A. Burhoe
  • Patent number: 8544378
    Abstract: A hydraulic system for construction equipment having a float function is provided. The hydraulic system can perform ground leveling as making a boom descend due to its own weight without using hydraulic fluid that is discharged from a hydraulic pump. The hydraulic system includes a holding logic poppet mounted in the float valve to prevent an abrupt descending of the boom due to leakage of the hydraulic fluid through a flow path between the main control valve and the float valve during the operation of the boom cylinders.
    Type: Grant
    Filed: June 7, 2010
    Date of Patent: October 1, 2013
    Assignee: Volvo Construction Equipment Holding Sweden AB
    Inventor: Jin Wook Kim
  • Patent number: 8474486
    Abstract: An actuator system (14) comprising a valve assembly (40) having an inner spool (50), an outer spool (60), and a sleeve (70). An assembly (80) directly drives the inner spool (50) to move it relative to the outer spool (60), and thereby hydromechanically causes the outer spool (60) to move relative to the sleeve (70). A control assembly (90) provides current input to the drive assembly (80), which converts current input into mechanical motion. The control assembly (90) senses the position of the inner spool (50) and regulates current in accordance with the sensed position.
    Type: Grant
    Filed: January 8, 2009
    Date of Patent: July 2, 2013
    Assignee: Parker-Hannifan Corporation
    Inventor: Luc P. Cyrot
  • Patent number: 8459019
    Abstract: A system and method for operating a two-stage, high-pressure pumping system includes a low-pressure pump having an output configured to deliver a hydraulic fluid under a low-pressure at a high-volume to drive a tool associated with the two-stage, high-pressure, pumping system under low load conditions. The system also includes a high-pressure pump having an output configured to deliver the hydraulic fluid under a high-pressure at a low-volume to drive the tool under high load conditions. A pilot-operated device is included that is configured to selectively drive the tool with pressure from at least one of the output of the low-pressure pump and the output of the high-pressure pump. The pilot-operated device receives pilot pressure from the output of the low-pressure pump to control selectively driving the tool with the output of the two stage pump.
    Type: Grant
    Filed: October 30, 2007
    Date of Patent: June 11, 2013
    Assignee: Actuant Corporation
    Inventor: Paul A. Hohensee
  • Patent number: 8356546
    Abstract: A holding control valve of the present invention is configured such that: a spool is configured to perform strokes by a piston configured to operate by introduction of pilot pressure and have a larger diameter than the spool; the piston is divided into a pilot piston configured to receive the pilot pressure and a relief operation piston disposed adjacent to the spool to receive pressure of relief oil discharged when a relief valve operates; and the relief oil is introduced to between the pilot piston and the relief operation piston.
    Type: Grant
    Filed: March 24, 2009
    Date of Patent: January 22, 2013
    Assignee: Kawasaki Jukogyo Kabushiki Kaisha
    Inventors: Masahiro Matsuo, Makoto Ito, Noboru Ito
  • Patent number: 8191363
    Abstract: A system for controlling motion of a hydraulic actuator on a refuse collection vehicle. The system includes an operator input device configured to produce a proportional electrical signal that is proportional to the degree of motion of the operator input device. The system further includes a proportional pneumatic control valve that is configured to produce a pressurized air control signal in proportion to the proportional electrical signal, and a hydraulic control valve that is configured to selectively control flow of hydraulic fluid to a hydraulic actuator in response to the pressurized air control signal.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: June 5, 2012
    Assignee: Hartfiel Automation, Inc.
    Inventors: Stephen P. Laumer, Gary Lee Lagro
  • Patent number: 8151688
    Abstract: A throttle path for returning a part of pilot oil to a tank is formed by a tank path provided in a valve block of a control valve and a notch provided in a spool thereof. The above path is opened within a section from a vicinity of a stroke where a hydraulic actuator starts moving to right before a stroke end among a spool stroke of the control valve. An opening area of the above path is slowly reduced in accordance with an increase in the stroke at a final phase of the section.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: April 10, 2012
    Assignee: Kobelco Construction Machinery Co., Ltd.
    Inventors: Yoshimi Saotome, Norifumi Shiraga
  • Patent number: 8065037
    Abstract: A control method and system for controlling a hydraulically actuated mechanical arm to perform a task, the mechanical arm optionally being a hydraulically actuated excavator arm. The method can include determining a dynamic model of the motion of the hydraulic arm for each hydraulic arm link by relating the input signal vector for each respective link to the output signal vector for the same link. Also the method can include determining an error signal for each link as the weighted sum of the differences between a measured position and a reference position and between the time derivatives of the measured position and the time derivatives of the reference position for each respective link. The weights used in the determination of the error signal can be determined from the constant coefficients of the dynamic model. The error signal can be applied in a closed negative feedback control loop to diminish or eliminate the error signal for each respective link.
    Type: Grant
    Filed: August 7, 2008
    Date of Patent: November 22, 2011
    Assignee: Board of Regents of the Nevada System of Higher Education, on Behalf of the University of Nevada, Reno
    Inventor: George Danko
  • Patent number: 7987765
    Abstract: A hydraulic control system for high flow applications in motor vehicles, in particular for active wheel suspensions and active steering arrangements, includes at least one passive high flow valve which is controlled hydraulically by at least one low flow valve.
    Type: Grant
    Filed: September 5, 2005
    Date of Patent: August 2, 2011
    Assignee: Lucas Automotive GmbH
    Inventors: Harry A. Hunnicutt, Gregory P. Campau, Dirk Kesselgruber
  • Patent number: 7814750
    Abstract: A device for supplying pressure from an energy storage device to a piston gear shifting actuator by way of a valve device is provided. A pressure regulating and/or control device is used to regulate and/or control the pressure applied to the piston actuator. The pressure regulating and/or control device regulates and/or controls the pressure according to at least one following quantity: temperature, in particular a transmission operating temperature, the load state of the motor vehicle provided with the transmission, and the slope of a surface along which the motor vehicle provided with the transmission runs.
    Type: Grant
    Filed: May 15, 2007
    Date of Patent: October 19, 2010
    Assignees: KNORR-BREMSE Systeme fuer Nutzfahzeuge GmbH, ZF Friedrichshafen AG
    Inventors: Markus Deeg, Friedbert Roether, Mario Steinborn, Rainer Petzold
  • Publication number: 20100212490
    Abstract: Control apparatus for a piston/cylinder arrangement, wherein the piston/cylinder arrangement has a cylinder and a piston which is accommodated at least partially in the cylinder and divides the cylinder interior along the cylinder axis into two part spaces, having a valve arrangement which is connected to a first part space and assumes a closed position which prevents a fluid which is held in the first part space from flowing out of this part space if the pressure in the fluid is smaller than a pressure control value which is set on the valve arrangement, and which opens into an opening position which makes this outflow possible if the pressure in the fluid is correspondingly greater than the pressure control value which has been set, having a priming device which is coupled to the valve arrangement and the first part space, serves to prepare for the damping of a pressure increase in the fluid which is brought about by a movement of the piston which is caused by a load which acts on the piston in the directio
    Type: Application
    Filed: August 14, 2006
    Publication date: August 26, 2010
    Applicant: LAEIS GmbH
    Inventors: Matthias Hahn, Ralph Lutz
  • Patent number: 7743791
    Abstract: The present invention generally relates to an air control module unit for a portable pneumatic tool, more particularly, to an air control module unit that actuates a valve stem inside an air inlet block of the air inlet module by a correspondent air bleed valve in the air actuation module. The air control module unit for a portable pneumatic tool comprising: an air inlet module, which has at least one valve stem inside an air inlet block, the air inlet block having plug screws on both ends towards the valve stem and one plug screw on the intersectional direction of the valve stem with at least one air inlet port opening for hooking up the compressed air; an air actuation module having a bleed valve inside the valve block; a plurality of flexible air hoses with a plurality of dimensions and being prepared for connecting the air inlet module and air actuation module; and a plurality of hose connectors and rubber seats with a plurality of types for connecting the air inlet module and the air operation module.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: June 29, 2010
    Assignee: China Pneumatic Corporation
    Inventor: George Chu
  • Patent number: 7634961
    Abstract: A hydraulic circuit including a first throttle disposed upstream of pressure-reducing valves of a remote-control valve, which operates a control valve of hydraulic pilot type, so as to reduce primary pressures supplied from a pilot pump to the pressure-reducing valves. Bleed-off lines connect pilot lines to tanks. Second throttles are disposed on the bleed-off lines, respectively, so as to moderate rises in the pilot pressures supplied to pilot ports of the control valve. The hydraulic circuit prevents detrimental effects such as deterioration of operability while ensuring shock absorption during quick operation.
    Type: Grant
    Filed: September 21, 2005
    Date of Patent: December 22, 2009
    Assignee: Kobelco Construction Machinery Co., Ltd.
    Inventors: Tomohiko Asakage, Yutaka Toji, Masaaki Tachino, Kazuhiko Fujii
  • Patent number: 7559271
    Abstract: Of a plurality of hydraulic signals output from an operating device, a hydraulic signal is input into a control valve serving as a hydraulic control device without conversion, and particular hydraulic signals are converted into electric signals corresponding to their hydraulic pressures by signal converting devices, such as pressure sensors, and are then input into a controller. The controller controls the drive of an electric actuator, such as a rotating electric motor, on the basis of the electric signals. Hydraulic fluid flow paths communicating to the pressure sensors are connected to each other via a throttle, and air in one of the hydraulic fluid flow paths is removed using the other hydraulic fluid flow path.
    Type: Grant
    Filed: October 10, 2006
    Date of Patent: July 14, 2009
    Assignee: Kobelco Construction Machinery Co., Ltd.
    Inventors: Masayuki Komiyama, Toshio Sora
  • Publication number: 20090090237
    Abstract: A control unit for a work machine that allows automatically obtaining optimal operability even when the weight of a work arm in the work machine is changed. In a work machine where at least a part of a work arm to be operated by a fluid pressure actuator is provided so as to be replaceable, a control unit for a work machine includes: a pilot-operated control valve that controls the fluid pressure actuator; a proportional solenoid valve that pilot-controls the pilot-operated control valve by a pilot control pressure according to an electrical signal corresponding to a manual operation amount; a measuring means that measures a weight of at least the part of the work arm; and a controller that converts characteristics between the manual operation amount and the pilot control pressure of the proportional solenoid valve to characteristics according to the weight of the work arm measured by the measuring means.
    Type: Application
    Filed: February 20, 2007
    Publication date: April 9, 2009
    Applicant: Shin Caterpillar Mitsubishi Co., Ltd.
    Inventors: Hiroyasu Nishikawa, Sei Shimahara, Manabu Nakanishi
  • Patent number: 7513109
    Abstract: There is provided a hydraulic controller for a working machine in which a pilot hydraulic pressure source is connected in common to a plurality of pilot-operated hydraulic devices each having a pilot pressure input unit, and a common pilot pressure input switching valve is adapted to control the switching between a pilot pressure input from the pilot hydraulic pressure source to each pilot pressure input unit and a relief of the input. The switching control of a pilot pressure input by the pilot pressure input switching valve is performed based on the operating state of the working machine and pilot pressure input conditions of the respective pilot-operated hydraulic devices.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: April 7, 2009
    Assignee: Kobelco Construction Machinery Co., Ltd.
    Inventors: Yutaka Toji, Yoichiro Yamazaki, Koji Yamashita, Hidekazu Oka, Koji Ueda
  • Publication number: 20090078112
    Abstract: The invention relates to a pilot valve (3) for a hydraulic motor which is used for lifting loads in a device. Said pilot valve (3) is designed as a directional control valve in which a control slide (20) is movably disposed in a longitudinal bore (22) of the valve body (21) so as to control the flow of hydraulic oil between two working connecting bores (A, B), a pump connecting bore (P), and a reservoir connecting bore (T). A check valve (32) which is biased with the aid of a bias spring (33) is disposed within the control slide (20). Said check valve (32) is connected to an auxiliary control groove (28) via a first transversal bore (29) while being connected to the B-reservoir groove (23) via a second transversal bore (31). The check valve (32) is to be opened from working connecting bore B while the auxiliary control groove (28) is arranged between the B control groove (24) and the B reservoir groove (23) and is delimited on both sides by means of sealing cylindrical areas (35, 36).
    Type: Application
    Filed: December 1, 2005
    Publication date: March 26, 2009
    Applicant: Bucher Hydraulics AG
    Inventor: Markus Eschweiler
  • Patent number: 7478530
    Abstract: A hydraulic circuit for a working machine includes hydraulic actuators which respectively drive a plurality of kinds of working devices and which are driven by a drive circuit having circuit states that correspond to the working devices, a directional control valve unit which, when one of the working devices is attached to the attachment, switches in response to a signal from a controller to select one of the circuit states, a detection sensor that detects the actual circuit state, and a display operated by the controller. The controller activates the display when the detected actual circuit state and the selected circuit state do not match.
    Type: Grant
    Filed: June 6, 2006
    Date of Patent: January 20, 2009
    Assignee: Kobelco Construction Machinery Co., Ltd.
    Inventor: Koji Ueda
  • Publication number: 20080276798
    Abstract: An asymmetric volume booster assembly includes an actuator movable in a first direction and a second direction, a first booster in fluid communication with the actuator, and a second booster in fluid communication with the actuator. The first booster includes a first supply passage and a first exhaust passage, wherein the first supply passage supplies fluid to the actuator and the first exhaust passage exhausts fluid from the actuator. The first exhaust passage is configured to produce a first fluid flow resistance. The second booster includes a second supply passage and a second exhaust passage, wherein the second supply passage supplies fluid to the actuator and the second exhaust passage exhausts fluid from the actuator. The second exhaust passage is configured to produce a second resistance to fluid flow. The first fluid flow resistance is greater than the second fluid flow resistance, such that the actuator moves substantially symmetrically in the first direction and the second direction.
    Type: Application
    Filed: July 25, 2008
    Publication date: November 13, 2008
    Applicant: FISHER CONTROLS INTERNATIONAL LLC
    Inventor: Kenneth W. Junk
  • Patent number: 7444920
    Abstract: The valve arrangement for the activation of a structural element has three inlet switching valves through which a pressure-loaded medium can be conducted. These inlet switching valves are connected on their inflow side to a pressure supply by inflow lines and are arranged parallel to one another in flow terms. Moreover, the valve arrangement has a connection element, which is connected to outflow sides of all the inlet valves by pressure lines. A control line acted upon by the medium is connected to the pressure supply. The three switching-valve groups can be activated by the control line, and in each case two switching valves and in each case one inlet switching valve are assigned to each switching-valve group. A activation valve can be interposed in each case between a switching-valve group and the control line. Three outflow lines for the medium can be arranged between an outflow location for the medium and the connection element.
    Type: Grant
    Filed: August 22, 2006
    Date of Patent: November 4, 2008
    Assignee: ABB Patent GmbH
    Inventors: Tobias Herrmann, Wolfgang Warmuth
  • Publication number: 20080257434
    Abstract: A hydraulic control system for high flow applications in motor vehicles, in particular for active wheel suspensions and active steering arrangements, includes at least one passive high flow valve which is controlled hydraulically by at least one low flow valve.
    Type: Application
    Filed: September 5, 2005
    Publication date: October 23, 2008
    Inventors: Harry A. Hunnicutt, Gregory P. Campau, Dirk Kesselgruber
  • Publication number: 20080250783
    Abstract: A hydraulic system comprises a plurality of primary hydraulic circuits and a secondary hydraulic circuit for satisfying flow continuity of the primary hydraulic circuits.
    Type: Application
    Filed: April 10, 2007
    Publication date: October 16, 2008
    Inventor: Daniel A Griswold
  • Patent number: 7430954
    Abstract: A work machine includes an attachment movable by an actuator, an operational member for operating the attachment through the actuator; and a controller operable to output an operation signal for operating the actuator in response to an operation of the operational member. The controller allows setting of a change amount in the operation signal corresponding to an operational amount of the operational member, independently for each operational direction of the actuator.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: October 7, 2008
    Assignee: Kubota Corporation
    Inventors: Keisuke Miura, Atsushi Matsumoto, Masaaki Ueda
  • Patent number: 7398647
    Abstract: A fastener driving tool includes a frame defining therein an accumulator that accumulates compressed air, a cylinder, a piston movable between a top dead center and a bottom dead center, a main valve section having a main valve movable between a top dead center and a bottom dead center to alternately open and block fluid communication between a piston upper chamber and the accumulator, a trigger valve section having a plunger movable between a top dead center and a bottom dead center so as to alternately open and block fluid communication from the accumulator to a main valve chamber, and fluid communication from the main valve chamber to atmosphere, and a trigger adapted to press the plunger when operated by a user. The piston moves from the top dead center to the bottom dead center within 11.3 msec when the plunger is pressed.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: July 15, 2008
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshiichi Komazaki, Yoshinori Ishizawa, Masashi Nishida
  • Publication number: 20080078286
    Abstract: A fluid power system includes a hydraulic machine. A pilot-controlled supply valve controls high-pressure fluid to the machine. The valve is coupled between the hydraulic machine and a high-pressure fluid source, and includes a control port for an actuation signal. The supply valve allows passage of fluid from the machine to the fluid source, but blocks passage of fluid from the fluid source to the machine while closed, or permits passage of fluid from the fluid source to the machine while open. The supply valve biases toward closed or open according to an actuation signal at the control port. A pressurization valve is also coupled between the hydraulic machine and the high-pressure fluid source. The pressurization valve blocks passage of fluid from the fluid source to the machine while in a first position, and allows a restricted passage of fluid between its input and output ports while in a second position, to allow pressure to equalize on either side of the supply valve before the supply valve opens.
    Type: Application
    Filed: September 29, 2006
    Publication date: April 3, 2008
    Applicants: Environmental Protection Agency
    Inventor: Charles L. Gray
  • Patent number: 7350355
    Abstract: A hydraulic system having at least one hydraulic valve for controlling a transmission, in particular a continuously variable transmission. The hydraulic valve is controlled by a pilot circuit including at least one control element having a variable flow resistance and one control element having a constant flow resistance. The control element having a variable flow resistance is connected upstream of the control element having a constant flow resistance.
    Type: Grant
    Filed: December 17, 2005
    Date of Patent: April 1, 2008
    Assignee: LuK Lamellen und Kupplungsbau Beteiligungs KG
    Inventor: Eric Müller
  • Patent number: 7278262
    Abstract: A control for a working apparatus having a boom arm. The apparatus includes a controller operable to receive signals from at least one pressure sensor. The at least one pressure sensor detects pressure of hydraulic fluid in at least one chamber of a control valve. The controller compares the signals from the at least one pressure sensor to parameters generated by testing the working apparatus. The controller predicts boom arm oscillations based on the comparison of the signals with the parameters, and generates a control signal in response to predicting the boom arm oscillations.
    Type: Grant
    Filed: September 12, 2005
    Date of Patent: October 9, 2007
    Assignee: Board of Control of Michigan Technological University
    Inventor: Kee Moon
  • Patent number: 7237473
    Abstract: A pneumatic valve includes a housing having an inlet port and a delivery port and an exhaust port. A valve element is movable in the housing to control air flow between the inlet port and the delivery port and the exhaust port. The valve includes a rolling element actuator for converting a rotary actuation force to linear movement of the valve element.
    Type: Grant
    Filed: July 21, 2005
    Date of Patent: July 3, 2007
    Assignee: Bendix Commercial Vehicle Systems
    Inventors: Robert J. Herbst, Travis Ramler
  • Patent number: 7228781
    Abstract: The invention relates to hydraulic control in a hydraulic system for the operation of a machine tool such as a press for processing material of a certain type, especially for the operation of the scrap cutters. Said control allows for impact attenuation and combined rapid motion switching with load compensation and transfer of a hydraulic medium of a hydraulic cylinder for the movement of the other. According to the invention, said control comprises hydraulic media of a hydraulic cylinder for pre-control of a first main valve element (2.4.0), a second main valve element (2.7.0) and a third main valve element (3.7.0) which are functionally combined and a fourth valve (2.5).
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: June 12, 2007
    Assignee: Metso Lindemann GmbH
    Inventors: Andreas Klother, Karl-Heinz Post
  • Patent number: 7228783
    Abstract: The present invention provides a pressure control system having a control solenoid with plurality of coils disposed therein, and operable to provide a plurality of pressure gain characteristics to a torque-transmitting mechanism. By selectively energizing the individual coils or a combination thereof, multiple pressure gains may be achieved with a minimum of additional system hardware.
    Type: Grant
    Filed: August 5, 2005
    Date of Patent: June 12, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Ronald F. Lochocki, Jr., Robert L. Moses, Shushan Bai
  • Patent number: 7188474
    Abstract: The invention relates to a reciprocating engine and a working fluid inlet system therefore. The engine includes at least one cylinder with a reciprocating piston therein and a variable volume expansion chamber capable of receiving a working fluid via an inlet valve. The inlet system includes a pilot valve having an open condition and a closed condition. In the open condition, the secondary fluid passes therethrough to act on the inlet valve. The system also includes an actuating means for controlling the condition of the pilot valve. The inlet valve is adapted to open in response to the action of the secondary fluid. The engine may also include exhaust means, possibly by porting in the piston and a cylinder wall. The working fluid may be used as the secondary fluid.
    Type: Grant
    Filed: September 27, 2004
    Date of Patent: March 13, 2007
    Assignee: Cogen Microsystems Pty Ltd.
    Inventor: Paul van de Loo
  • Patent number: 7174826
    Abstract: A crowd control mechanism for a power shovel includes an extendible dipper handle having an extended position and a retracted position. A double acting hydraulic cylinder having a an extendible ram has one of the cylinder and the ram fixed to the dipper handle and the other of the cylinder and the ram is stationary relative to the dipper handle. At least one of the cylinder and the ram have at least one of a blind end port and a rod end port, and at least one of the cylinder and the ram have the other of the blind end port and the rod end port, wherein hydraulic fluid flowing into the cylinder through the blind end port urges the ram toward an extended position to extend the dipper handle, and hydraulic fluid flowing into the rod end port urges the ram toward a retracted position to retract the dipper handle. Hydraulic fluid flowing into and out of the cylinder is controlled by one or more pilot operated poppet valves.
    Type: Grant
    Filed: January 24, 2005
    Date of Patent: February 13, 2007
    Assignee: Bucyrus International, Inc.
    Inventors: Timothy R. Kerrigan, Carl D. Gilmore, Matthew Brueck, Jeanne M. Yaunke, Michael Haws, Michael G. Onsager
  • Patent number: 7156012
    Abstract: A pneumatically operated fastener driving tool capable of reducing a time period from operation timing of a trigger to downward movement of a driver blade for fastener driving, and reducing a time period from the release timing of the trigger to a timing at which respective components are returned to their initial positions for a subsequent nail driving. As components a main valve and a trigger valve is provided. The main valve is movable within a main valve chamber connected to a main valve control channel. The trigger valve selectively provides fluid communication between the accumulator and a main valve chamber through the main valve control channel and between the main valve chamber and the atmosphere through the main valve control channel. A ratio of cross-sectional area of the main valve control channel to an internal volume of the main valve chamber is defined to a specified ratio.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: January 2, 2007
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshiichi Komazaki, Yoshinori Ishizawa, Masashi Nishida
  • Patent number: 7066075
    Abstract: The present invention is a transbrake system for a transmission of a drag race car, the transmission comprising: (a) a transmission housing having an exterior, typically of aluminum; (b) a transmission valve body contained in the transmission housing; the transmission housing having an aperture connecting the exterior of the transmission housing with the transmission valve body; (c) a pneumatic solenoid disposed outside the transmission housing and having an actuating piston extending through the aperture to the transmission valve body, so as to be moveable from a position braking the transmission to a position releasing the transmission; (d) a source of compressed air; (d) an electrical air control valve to control the supply of compressed air from the source of compressed air to the pneumatic solenoid; (e) a fluid conduit extending from the electrical air control valve to the pneumatic solenoid.
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: June 27, 2006
    Inventor: Julius Clifton Callis, Jr.