Patents Represented by Attorney, Agent or Law Firm J. W. Burrows
  • Patent number: 6357230
    Abstract: A hydraulic ride control system is disclosed and adapted to control the ride of a machine having a load. The ride control includes an accumulator arrangement that is selectively connected with the actuator that is carrying the load to provide a cushion ride during traveling and to enable the pressure in the accumulator arrangement to be maintained substantially the same as the pressure in the actuator when raising the load and to permit the pressure in the accumulator arrangement to be lowered to that of the pressure in the actuator in the event the load is lessened. The ride control system also provides an arrangement that permits the accumulator arrangement to be bled down whenever the machine becomes disabled or when the machine is shut off.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: March 19, 2002
    Assignee: Caterpillar Inc.
    Inventors: Michael A. A'Hearn, David J. Carlson, Thomas J. Hajek, Jr., Andy Hatcher, Michael D. Hudson, Patrick Quinn, Srikrishnan T. Tolappa
  • Patent number: 6318234
    Abstract: A line vent arrangement is provided to selectively vent pressurized fluid from an actuator in an electro-hydraulic system when an engine of a machine has been shut down. This is accomplished by providing a pressure storage arrangement in parallel with a source of pressurized pilot fluid and an electrically controlled valve that is movable to a position to connect the pressure storage arrangement to the electro-hydraulic directional control valve when the engine of the machine has been shut down.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: November 20, 2001
    Assignee: Caterpillar Inc.
    Inventor: Edward W. Mate
  • Patent number: 6318347
    Abstract: An air-to-air aftercooler or heat exchanger for a vehicular internal combustion engine, which is independent of the main vehicle heat exchanger or radiator, and which is located at a position upon the vehicle which is remote from the main vehicle heat exchanger or radiator, has a filter for filtering ambient air; at least one aftercooler heat exchanger, separate from the main radiator heat exchanger and disposed upon the engine at a location remote from the main radiator heat exchanger, and having a first passageway defined therein which is fluidically connected to the filter for receiving the ambient air which has passed through the filter; a second passageway defined within the at least one aftercooler heat exchanger for receiving turbocharged air from the turbocharger, for conducting the turbocharged air through the at least one aftercooler heat exchanger such that the turbocharged air undergoes a heat exchange process with the ambient air, and for conducting the turbocharged air to the engine intake manif
    Type: Grant
    Filed: June 29, 2000
    Date of Patent: November 20, 2001
    Assignee: Caterpillar Inc.
    Inventors: Paul A. Dicke, Ronald L. Dupree, Donald C. Hodges, Jiubo Ma, Aubery W. Penn
  • Patent number: 6299391
    Abstract: A boring tool assembly is provided and has a cutting tool mounted on one end thereof and permits the boring of a straight hole through a member. The boring tool assembly includes a boring bar having integral guide members disposed thereon that follows behind the cutting tool and maintains contact with the machined surface just cut in order to keep the cutting tool in proper alignment. To permit the continued use of the boring bar after the outer diameter of the cutting tool has been reduced due to wear, each of the integral guide members are resiliently mounted on the boring bar. This permits the guide members to collapses inwardly to maintain a perfect fit with the pilot pore while maintaining bearing contact of the guide members with the pilot bore. The positive bearing contact helps to provide a dampening feature for the boring bar and a spring type force for the hardened guide members.
    Type: Grant
    Filed: June 14, 1999
    Date of Patent: October 9, 2001
    Assignee: Caterpillar Inc.
    Inventors: John C. Endsley, Michael H. Hinrichsen
  • Patent number: 6295746
    Abstract: A method and apparatus for controlling movement of a work implement movably connected to a work machine. Movement of the work implement is controlled by manual and automatic control valves that are associated with “manual” and “automatic” modes of operation. The manual and automatic control valves are connected between hydraulic motors for controlling movement of the work implement and a hydraulic fluid supply. Each of the manual and automatic control valves governs hydraulic fluid flow to the hydraulic motors. A pressure sensing device is associated with the manual control valves to detect operator modulation of the manual control valves and thereby alter operation of the automatic control valves in the “automatic” mode on the same side of the implement.
    Type: Grant
    Filed: December 9, 1999
    Date of Patent: October 2, 2001
    Assignee: Caterpillar Inc.
    Inventors: Gregory L. Meduna, Jeffrey L. Slunder
  • 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: 6224065
    Abstract: A face seal for forming a sealed condition between two spaced, opposed surfaces. The face seal includes an inner seal retainer member and an outer seal retainer member each defining an area having an axis therethrough. The inner and outer seal retainer members each having a first axial end portion, an opposite second axial end portion, and an axial extent as measured between the first axial end portion and the second axial end portion. The outer seal retainer member is disposed radially outwardly of the inner seal retainer member, defining a space therebetween. An elastomeric seal member having an axial extent longer than the axial extent of the first and second inner and outer seal retainer members is disposed in a predetermined portion of the space between the inner seal retainer member and the outer seal retainer member.
    Type: Grant
    Filed: May 7, 1999
    Date of Patent: May 1, 2001
    Assignee: Caterpillar Inc.
    Inventor: David P. Smith
  • Patent number: 6205781
    Abstract: A fluid control system including a valve arrangement operable for selectively, controllably supplying pressurized fluid to a work element of the system from at least two pressurized fluid sources depending on load conditions on the pressurized fluid sources. The valve arrangement is operable for directing pressurized fluid from the first pressurized fluid source to the work element when a first or low load condition is present on the first pressurized fluid source and directing pressurized fluid from the second pressurized fluid source to the work element when a second or high load condition greater than the first load condition is present on the first pressurized fluid source and a low load condition is present on the second pressurized fluid source, such that operability of the work element and other work elements supplied by the pressurized fluid sources is maintained.
    Type: Grant
    Filed: February 25, 1999
    Date of Patent: March 27, 2001
    Assignee: Caterpillar Inc.
    Inventor: Michael A. A'Hearn
  • Patent number: 6199378
    Abstract: A control arrangement operates in conjunction with a control scheme to control the maximum pressure level within a conduit network of a fluid system without the need to have high flow pressure relief valves. The control arrangement provides a low flow pressure relief valve connected in parallel with an electrically actuated valve mechanism to trim any over-pressure conditions so that the control scheme has more time to move the electrically actuated valve mechanism to a flow bypassing, pressure relieving position.
    Type: Grant
    Filed: September 21, 1999
    Date of Patent: March 13, 2001
    Assignee: Caterpillar Inc.
    Inventors: James A. Aardema, Thomas J. Hajek, Jr., Douglas W. Koehler, Edward W. Mate, Vincent Triffaux
  • Patent number: 6186044
    Abstract: A fluid control system provides a float capability for a double-acting actuator. The system includes pilot operated check valves disposed between the double-acting actuator and first and second ports of a pilot operated directional control valve. The directional control valve and the check valves are cooperatively operable under first and second pilot signal conditions to extend and retract the double-acting actuator. The system includes a valve arrangement connected to the check valves and the directional control valve for producing the first and second pilot signal conditions thereon, including also directing the first pilot signal condition to the second pilot signal condition when the first pilot signal condition reaches a predetermined signal strength, to initiate a float capability.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: February 13, 2001
    Assignee: Caterpillar Inc.
    Inventors: Thomas J. Hajek, Jr., Srikrishnan T. Tolappa
  • Patent number: 6179570
    Abstract: A variable pump control for a hydraulic fan drive is provided to control the speed of the fan between a maximum and a minimum desired value. A proportional solenoid valve arrangement is provided to established a maximum displacement of a variable displacement pump which drive a fluid motor having a cooling fan attached thereto. A variable electrical signal is directed to the proportional solenoid valve arrangement to proportionally reduce the displacement of the pump thus reducing the speed of the cooling fan to a predetermined minimum desired level.
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: January 30, 2001
    Assignee: Caterpillar Inc.
    Inventor: David P. Smith
  • Patent number: 6176684
    Abstract: A variable displacement hydraulic piston unit with electrically operated variable displacement control and timing control is disclosed, the displacement control utilizing an electric motor such as a stepper motor and cam arrangement operable for changing the tilt angle of a swash plate of the unit, and the timing control including an electric motor, such as a stepper motor operable for rotating the swash plate relative to the pistons of the unit for effecting timing changes, the unit being operable as a pump, motor, or the like.
    Type: Grant
    Filed: November 30, 1998
    Date of Patent: January 23, 2001
    Assignee: Caterpillar Inc.
    Inventor: Daniel E. Zimmermann
  • Patent number: 6175083
    Abstract: A sealing mechanism is provided to seal a lead from a closed cavity of an apparatus. The sealing mechanism includes a mounting portion sealingly connected to the apparatus, a cap member having a recess defined therein with an elastomeric grommet compressively disposed in the recess. The elastomeric grommet has a passageway defined therethrough for the lead from the closed cavity to past through. The compressive forces induced into the elastomeric grommet applies a compressive force on the lead to provide a seal. The cap member is sealingly connected to the mounting portion. Consequently, the closed cavity in the apparatus is effectively sealed from the atmosphere and contaminants cannot enter the closed cavity and create premature failure of the component therein, such as, for example, an electrical coil.
    Type: Grant
    Filed: December 11, 1998
    Date of Patent: January 16, 2001
    Assignee: Caterpillar Inc.
    Inventors: Clarence K. Palmer, Kenneth M. Roat, Thomas R. Springer
  • Patent number: 6173639
    Abstract: A fluid control circuit providing a float capability for a double-acting actuator having first and second actuating chambers is provided. The fluid circuit includes signal controlled load check valves disposed between the actuating chambers and a directional control valve. The directional control valve is movable from a centered, neutral position towards first and second operative positions and a float position. The directional control valve and the load check valves are cooperatively operable in one operable position to allow fluid flow from the first actuating chamber to the exhaust port, and fluid flow from the pump port to the second actuating chamber. In the float position of the directional control valve, both of the signal controlled load check valves are opened to allow open fluid flow between the first and second actuating chambers thus allowing the tool attached to the actuator to float.
    Type: Grant
    Filed: May 7, 1999
    Date of Patent: January 16, 2001
    Assignee: Caterpillar Inc.
    Inventors: Michael A. A'Hearn, Thomas J. Hajek, Jr., Srikrishnan T. Tolappa
  • Patent number: 6167701
    Abstract: A variable rate ride control is disclosed and adapted to control the ride of a machine having varying load conditions. The variable rate ride control system includes an accumulator arrangement selectively connectable to an actuator arrangement of the machine. The accumulator arrangement has a variable pressure rate so that the accumulator arrangement can adapt to varying load conditions.
    Type: Grant
    Filed: July 6, 1998
    Date of Patent: January 2, 2001
    Assignee: Caterpillar Inc.
    Inventors: Andrew Hatcher, Patrick Quinn
  • Patent number: 6139020
    Abstract: A seal is provided having a back surface that is generally perpendicular with a longitudinal axis of the seal and a sealing portion on the side opposite the back surface. The sealing portion is defined by first and second intersecting surfaces. A plurality of projections are disposed on one of the first and second surfaces at a location generally adjacent the intersection of the surfaces and a cylindrical recess is defined in at least a portion of the plurality of projections. The sides of the cylindrical recesses and the plurality of projections are oriented perpendicular to the back surface to enhance the ability to manufacture the seal in an economical manner.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: October 31, 2000
    Assignee: Caterpillar Inc.
    Inventors: Anthony D. Friend, Alan M. Dickey
  • Patent number: 6127912
    Abstract: A bobbin for an encapsulated coil is provided for use in a coil assembly in which flange portions are provided on each end to ensure that during the process of encapsulating the coil with an over-molded material a positive seal is established between the bobbin and the over-molded material. Each of the flange portions have first, second, and third flange sections and each of the flange sections have predetermined diameters and peripheral surfaces that are angled with respect to a reference axis of a hole defined in the bobbin. The thin sharp edges formed by the peripheral surfaces of the respective flange sections melt back during the over-molding process. This melt back creates an intricate blend between the over-molded material and the bobbin thus producing a positive seal therebetween.
    Type: Grant
    Filed: August 3, 1998
    Date of Patent: October 3, 2000
    Assignee: Caterpillar Inc.
    Inventors: Maurice J. Dust, John A. Hoffman, II
  • Patent number: 6121865
    Abstract: A solenoid assembly is provided having a sealing device disposed in a recess of the over-molded material in order to seal the electrical leads extending from the coil of the solenoid through the recess. The sealing device is an elastomeric member having holes defined therein for the electrical leads to pass through and a larger portion that is disposed in the recess. With the larger portion pressed into the recess, a force is transferred through the elastomeric material onto the electrical leads to prohibit ingression of contaminants into the windings of the coil. The electrical leads could be either lead wires or rigid pins. The elastomeric material also serves to provide vibration damping.
    Type: Grant
    Filed: August 3, 1998
    Date of Patent: September 19, 2000
    Assignee: Caterpillar Inc.
    Inventors: Maurice J. Dust, Kyle W. Scholl
  • Patent number: 6098481
    Abstract: A high force detent mechanism to selectively hold a control input lever in any selected position between neutral and its maximum travel in either direction. The high force detent mechanism includes a coil assembly connected to a control input lever and disposed in close proximity to a semi-circular member having a serrated edge defined thereon. An armature of the coil assembly has a first portion in driving contact with the serrated edge and a second enlarge portion having a latching surface disposed adjacent one of the first and second end faces of the coil assembly's detent coil. The size of the latching surface is larger than the size of the first portion that is in driving contact with the serrated edge. Consequently, the latching force generated between the latching surface and the one face of the detent coil is multiplied several time to create a detent holding force that is larger than the latching force.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: August 8, 2000
    Assignee: Caterpillar Inc.
    Inventors: Rudy V. Mills, David P. Smith
  • Patent number: H1912
    Abstract: A remotely controlled brake system is provided to permit braking control of a machine from a remote location while still permitting an operator located on the machine to control the braking function of the machine. Remote control is accomplished by providing a source of pressurized fluid on the machine with an electrically controlled proportional valve arrangement that is responsive to a remote signal to direct pressurized fluid to the brakes of the machine in parallel with the pressure control being directed to the machine brakes by an operator input mechanism.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: November 7, 2000
    Assignee: Caterpillar Inc.
    Inventor: Robin S. Arndt