Patents by Inventor David P. Smith

David P. Smith has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7631738
    Abstract: A sprag is disclosed. The sprag is configured to operate in a first mode allowing substantially mutual rotation of inner and outer races about an axis and a second mode allowing relative rotation between the inner and outer races. The sprag includes at least one actuator configured to selectively extend and retract and an outer surface configured to selectively lock the inner and outer races together as a function of the at least one actuator selectively extending.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: December 15, 2009
    Assignee: Caterpillar Inc.
    Inventors: David P. Smith, Eric R. Lauterbach, Daniel T. Mather, Jonathan L. Buelow
  • Publication number: 20090084536
    Abstract: A technique provides an orientation system combined with downhole equipment used in a well. An orientation device is mounted in the downhole equipment, e.g. a bottom hole assembly, for actuation during angular displacement of the downhole equipment. A sensor is mounted to cooperate with the orientation device in detecting the angular displacement.
    Type: Application
    Filed: October 2, 2007
    Publication date: April 2, 2009
    Inventors: Michael H. Kenison, L. Michael McKee, Robert Bucher, David P. Smith, Sarmad Adnan
  • Patent number: 7497156
    Abstract: A fluid motor including an inner race and an outer race is disclosed. The inner and outer races are configured to rotate about a substantially common axis. The motor also includes at least one fluid actuator configured to produce substantially linear motion as a function of selectively receiving pressurized fluid. The fluid motor also includes at least one sprag configured to rotate the inner and outer races about the axis as a function of the substantially linear motion.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: March 3, 2009
    Assignee: Caterpillar Inc.
    Inventors: David P. Smith, Eric R. Lauterbach, Daniel T. Mather, Jonathan L. Buelow
  • Patent number: 7444809
    Abstract: A hydraulic system for a work machine is provided. The hydraulic regeneration system has a tank, a primary source, a first actuator, an accumulator, and a first valve mechanism. The tank is configured to hold a supply of fluid. The primary source is configured to pressurize the fluid and has a suction inlet and a discharge outlet. The first actuator is configured to receive pressurized fluid from the discharge outlet of the primary source. The accumulator is in fluid communication with the tank, the suction inlet of the primary source, and the first actuator. The first valve mechanism is disposed between the suction inlet of the primary source and the accumulator, and is movable between a first position at which fluid returning from the first actuator is directed to the suction inlet of the primary source, and a second position at which fluid returning from the first actuator is directed to only the accumulator.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: November 4, 2008
    Assignees: Caterpillar Inc., Shin Caterpillar Mitsubishi Ltd
    Inventors: David P. Smith, Daniel T. Mather
  • Publication number: 20080238246
    Abstract: An actuator includes a frame and a shaft rotabably supported by the frame. The actuator also includes at least one wire made from a shape memory alloy having a first end thereof fixed with respect to the frame. A second end of the at least one wire is movable with respect to the frame and configured to rotate the shaft in a first direction with respect to the frame.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 2, 2008
    Inventor: David P. Smith
  • Publication number: 20080155976
    Abstract: A hydraulic motor is disclosed. The hydraulic motor includes a first toothed wheel and at least one second toothed wheel configured to at least selectively engage the first toothed wheel. The hydraulic motor also includes at least one hydraulic actuator and at least one linkage operatively disposed between the at least one second toothed wheel. The at least one linkage configured to transfer a reciprocal motion of the at least one hydraulic actuator to a rotary motion of the first toothed wheel.
    Type: Application
    Filed: December 28, 2006
    Publication date: July 3, 2008
    Inventors: David P. Smith, Eric R. Lauterbach, Daniel T. Mather
  • Publication number: 20080156596
    Abstract: A sprag and bearing system including a sprag is disclosed. The sprag includes an integral body having an oblong cross sectional circumference at least one actuator configured to selectively rotate the body about an axis in a first direction. The sprag also includes at least one spring configured to bias the body to rotate about the axis in a second direction.
    Type: Application
    Filed: December 28, 2006
    Publication date: July 3, 2008
    Inventors: David P. Smith, Eric R. Lauterbach, Daniel T. Mather
  • Publication number: 20080098882
    Abstract: A fluid motor including an inner race and an outer race is disclosed. The inner and outer races are configured to rotate about a substantially common axis. The motor also includes at least one fluid actuator configured to produce substantially linear motion as a function of selectively receiving pressurized fluid. The fluid motor also includes at least one sprag configured to rotate the inner and outer races about the axis as a function of the substantially linear motion.
    Type: Application
    Filed: October 31, 2006
    Publication date: May 1, 2008
    Inventors: David P. Smith, Eric R. Lauterbach, Daniel T. Mather, Jonathan L. Buelow
  • Publication number: 20080099304
    Abstract: A sprag is disclosed. The sprag is configured to operate in a first mode allowing substantially mutual rotation of inner and outer races about an axis and a second mode allowing relative rotation between the inner and outer races. The sprag includes at least one actuator configured to selectively extend and retract and an outer surface configured to selectively lock the inner and outer races together as a function of the at least one actuator selectively extending.
    Type: Application
    Filed: October 31, 2006
    Publication date: May 1, 2008
    Inventors: David P. Smith, Eric R. Lauterbach, Daniel T. Mather, Jonathan L. Buelow
  • Patent number: 7293579
    Abstract: A poppet valve arrangement is provided and has a poppet slideably disposed therein. The poppet has an odd number of integral guide legs formed thereon about the periphery of the poppet. The odd number of integral guide legs are evenly spaced from one another and are of a size sufficient to permit fluid to freely flow thereby when unseated. The integral guide legs also function to permit the poppet to freely slide, without binding, within a bore of the poppet valve arrangement. The poppet having integral guide legs is compact, versatile, cost effective to produce and has good strength.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: November 13, 2007
    Assignee: Caterpillar Inc.
    Inventors: James A. Aardema, Rudy V. Mills, David P. Smith
  • Patent number: 7258058
    Abstract: A metering valve for a work machine hydraulic system is disclosed. The metering valve has an inlet and an outlet, a main poppet, and a solenoid-operated pilot element. The main poppet is movable to pass fluid from the inlet to the outlet, and to block fluid from the inlet to the outlet. The solenoid-operated pilot element is movable between a first position at which pressurized fluid from the inlet pressurizes a control chamber in communication with a control end of the main poppet to urge the main poppet toward the flow-blocking position, and a second position at which the control chamber is communicated with a drain to move the main poppet toward the flow-passing position. The metering valve also has a relief valve element configured to drain pressurized fluid from the control chamber to move the main poppet toward the flow-passing position in response to a pressure at the inlet exceeding a predetermined pressure.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: August 21, 2007
    Assignees: Caterpillar Inc, Shin Caterpillar Mitsubishi Ltd.
    Inventors: David P. Smith, Daniel T. Mather, Wayne W. Lark
  • Patent number: 7240604
    Abstract: A metering valve for a work machine hydraulic system is disclosed. The metering valve has a valve body with an inlet and an outlet. The metering valve also has a main poppet disposed within the valve body between the inlet and the outlet. The main poppet has a nose end and a chamber end, and is movable between a flow-passing position at which fluid flows from the inlet to the outlet, and a flow-blocking position at which fluid flow between the inlet and outlet is blocked. The metering valve also has a pilot element movable to selectively communicate the chamber end of the main poppet with a drain, thereby affecting movement of the main poppet between the flow-passing and flow-blocking positions. The metering valve further has a solenoid mechanism operable to move the pilot element. The position of the pilot element is affected by a fluid pressure at the inlet.
    Type: Grant
    Filed: July 29, 2005
    Date of Patent: July 10, 2007
    Assignees: Caterpillar Inc, Shin Caterpillar Mitsubishi Ltd.
    Inventors: David P. Smith, Daniel T. Mather
  • Patent number: 6935114
    Abstract: A system and method for starting an engine having a crankshaft is provided. Pressurized fluid is stored in an accumulator. A flow of pressurized fluid is released from the accumulator. The flow of pressurized fluid released from the accumulator is directed to a pump that is operatively engaged with the crankshaft of the engine. The flow of pressurized fluid drives the pump to generate a rotation of the crankshaft and thereby start the engine.
    Type: Grant
    Filed: November 25, 2002
    Date of Patent: August 30, 2005
    Assignee: Caterpillar Inc
    Inventors: Thomas J. Hajek, David P. Smith
  • Patent number: 6848475
    Abstract: An electro-hydraulic valve is provided for use in a system to control flow and/or pressure within the system. An electro-hydraulic valve arrangement includes a housing and a valving mechanism disposed in the housing. The electro-hydraulic valve arrangement has a hold coil assembly connected to the housing adjacent to the valving mechanism. A force control member having a clapper face is positioned adjacent to the hold coil assembly and the clapper face thereof is maintained at a predetermined distance from a coil face of the hold coil assembly. A double precision adjustment mechanism is operative associated with the force control member and is operative to precisely control the distance between the coil face and the clapper face.
    Type: Grant
    Filed: November 20, 2002
    Date of Patent: February 1, 2005
    Assignee: Caterpillar Inc.
    Inventor: David P. Smith
  • Patent number: 6769252
    Abstract: A fluid control system includes a pressure supply and a valve arrangement having an inlet and an outlet and being in fluid communication with the pressure supply. The valve arrangement includes a relief operator configured to provide fluid communication between the inlet and the outlet of the valve arrangement in response to a predetermined pressure condition at said inlet. The valve arrangement is configured to provide fluid communication between the inlet and the outlet of the valve arrangement in response to an outlet pressure being greater than an inlet pressure.
    Type: Grant
    Filed: December 10, 2001
    Date of Patent: August 3, 2004
    Assignee: Caterpillar Inc
    Inventor: David P. Smith
  • Patent number: 6748738
    Abstract: A hydraulic regeneration system for a work machine is provided. The hydraulic regeneration system includes a first hydraulic actuator having a first chamber and a second chamber, a second hydraulic actuator having a third chamber and a fourth chamber, and a source of pressurized fluid. A first directional control valve is disposed between the source of pressurized fluid and the first chamber of the first hydraulic actuator and the third chamber of the second hydraulic actuator. A second directional control valve is disposed between the source of pressurized fluid and the second chamber of the first hydraulic actuator and the fourth chamber of the second hydraulic actuator. An accumulator may also be used to store pressurized fluid and selectively supply pressurized fluid to increase the efficiency of the work machine.
    Type: Grant
    Filed: May 17, 2002
    Date of Patent: June 15, 2004
    Assignees: Caterpillar Inc., Shin Caterpillar Mitsubishi Ltd
    Inventor: David P. Smith
  • Publication number: 20040094218
    Abstract: An electro-hydraulic valve is provided for use in a system to control flow and/or pressure within the system. An electro-hydraulic valve arrangement includes a housing and a valving mechanism disposed in the housing. The electro-hydraulic valve arrangement has a hold coil assembly connected to the housing adjacent to the valving mechanism. A force control member having a clapper face is positioned adjacent to the hold coil assembly and the clapper face thereof is maintained at a predetermined distance from a coil face of the hold coil assembly. A double precision adjustment mechanism is operative associated with the force control member and is operative to precisely control the distance between the coil face and the clapper face.
    Type: Application
    Filed: November 20, 2002
    Publication date: May 20, 2004
    Inventor: David P. Smith
  • Patent number: 6699311
    Abstract: A fluid circuit for raising and lowering an implement including a quick drop valve member movable between at least a first position and a second position, the first position corresponding to a non-quick drop hydraulic fluid flow path of the fluid circuit and the second position corresponding to a quick drop hydraulic fluid flow path of the fluid circuit, the quick drop valve member being movable between at least the first and second positions based on pressures in the fluid circuit produced by hydraulic fluid. The fluid circuit further including a control system configured to selectively apply a biasing force against the quick drop valve member biasing the quick drop valve in the first position, the control system providing the biasing force independent of pressures in the fluid circuit produced by the hydraulic fluid.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: March 2, 2004
    Assignee: Caterpillar Inc
    Inventors: David P. Smith, Rudy V. Mills, Robert A. Aarestad, Chad T. Brickner
  • Patent number: 6694859
    Abstract: A single stage, electrically controlled variable pressure relief valve assembly is provided that uses a valving element assembly slideably disposed within a housing having first and second inlet and outlet ports, the valving element assembly has a differential area defined thereon which acts in cooperation with an electrically controlled coil assembly to proportionally control the flow of fluid between the inlet port and an outlet ports of the housing. The valving element assembly has inlet and outlet ports that are oriented generally perpendicular to the flow of the fluid through the valving element assembly to effectively offset the effects of flow forces acting on the valving element.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: February 24, 2004
    Assignee: Caterpillar Inc
    Inventor: David P. Smith
  • Patent number: 6684636
    Abstract: A method is provided for controlling displacement of a variable displacement pump coupled to a load. The method includes determining an electrical signal to be applied to a proportional solenoid for a desired pump displacement based on known pump characteristics. The electrical signal is provided to the proportional solenoid. The displacement of the variable displacement pump is controlled based on the electrical signal to the proportional solenoid.
    Type: Grant
    Filed: October 26, 2001
    Date of Patent: February 3, 2004
    Assignee: Caterpillar Inc
    Inventor: David P. Smith