Patents by Inventor Michael F. Coffman

Michael F. Coffman 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: 6975930
    Abstract: A method of controlling an operation of a mechanism is provided. A first rate limit is assigned to a first input device that is operable to generate a first signal to control the operation of the mechanism. A second rate limit is assigned to a second input device that is operable to generate a second signal to control the operation of the mechanism. At least one of the first and second input devices are manipulated to effect a desired change in the operation of the mechanism. A maximum allowable rate of change in the operation of the mechanism is identified based on the first and second signals and the first and second rate limits. A rate of change in the operation of the mechanism to achieve the desired change in the operation of the mechanism is determined based on a comparison of the maximum allowable rate of change in the operation of the mechanism with a last used rate of change in the operation of the mechanism.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: December 13, 2005
    Assignee: Caterpillar Inc.
    Inventors: Benjamin D. Drake, Timothy M. Gutzwiller, Michael F. Coffman, Timothy A Feucht
  • Patent number: 5456333
    Abstract: An electrohydraulic control device for a drive train of a vehicle including an engine, a transmission, a source of pressurized fluid, and an input clutch driving connected between the engine and the transmission. The device includes a control lever or handle having a control member progressively manually movable between first and second positions, wherein the transmission is adapted to responsibly shift between a FORWARD and a REVERSE gear ratio in response to movement of the control member from the first position to the second position. An electronic control module is adapted to determine a transmission clutch relative speed as a function of the transmission output speed and the transmission input speed and responsively engage and disengage the input clutch during a directional shift.
    Type: Grant
    Filed: March 25, 1993
    Date of Patent: October 10, 1995
    Assignee: Caterpillar Inc.
    Inventors: Chris D. Brandt, Michael F. Coffman, Randall M. Mitchell
  • Patent number: 5380257
    Abstract: An electrohydraulic control device for a drive train of a vehicle is provided. The drive train includes an engine, a transmission, a source of pressurized fluid, and an input clutch connected between the engine and the transmission. The control device senses the rotational output speed of the engine and responsively engages and disengages the input clutch as a function of the engine speed.
    Type: Grant
    Filed: March 25, 1993
    Date of Patent: January 10, 1995
    Assignee: Caterpillar Inc.
    Inventors: Michael F. Coffman, Paul E. Jantz
  • Patent number: 5371460
    Abstract: An apparatus for determining the speed and direction of a rotating shaft is provided. The apparatus includes a rotor connected to the shaft. The rotor has a plurality of teeth of alternating widths. The apparatus detects the teeth and responsibly determines the speed and direction of rotation of the shaft.
    Type: Grant
    Filed: September 21, 1992
    Date of Patent: December 6, 1994
    Assignee: Caterpillar Inc.
    Inventors: Michael F. Coffman, Steven W. Judy
  • Patent number: 5040648
    Abstract: A vehicle such as an earthmoving wheel loader has an engine, a torque converter having an impeller element, a reactor element and a turbine element, and an input clutch connected between the engine and the impeller element. An electrohydraulic control device is provided to controllably engage the input clutch and that includes a microprocessor-based electronic control module, an actuator mechanism having a control member that is progressively movable between first, second and third positions to deliver a first electrical signal to the electronic control module, and a valve for directing fluid to the input clutch at a decreasing pressure level when the control member is moved from the first to the second positions in response to another signal from the electronic control module. The electronic control module is programmed to maintain at least a minimal pressure level to the actuating piston of the input clutch when the control member is between the second and third positions.
    Type: Grant
    Filed: November 5, 1990
    Date of Patent: August 20, 1991
    Assignee: Caterpillar Inc.
    Inventors: Randall M. Mitchell, David W. Bump, deceased, Michael F. Coffman, Dwight S. Holloway, Lowell E. Johnson, Tony L. Marcott, Philip C. McKenzie, Noel J. Rytter