Patents Represented by Attorney, Agent or Law Firm Samuel Digirolamo
  • Patent number: 6298933
    Abstract: A main frame to roller frame stop assembly for limiting movement of an equalizer bar relative to the main frame of a track-type tractor or other work machine wherein the stop assembly includes a first member mountable to one of the roller frames, and a second member mountable to the main frame of the work machine, the second member being positioned and located to engage the first member when the equalizer bar moves a predetermined distance relative to the main frame, the first member being positioned and located in the vicinity of the bearing joint coupling the equalizer bar to the roller frame and further including an elastomeric portion capable of dampening and absorbing at least a portion of the load exerted thereagainst when the first stop member engages the second stop member.
    Type: Grant
    Filed: October 8, 1999
    Date of Patent: October 9, 2001
    Assignee: Caterpillar Inc.
    Inventor: Gerald P. Simmons
  • Patent number: 6112765
    Abstract: In one embodiment of the present invention a method for monitoring operation of a solenoid actuated gaseous fuel admission valve is provided by measuring the resistance across a movable metering plate and a stationary plate in the valve. The plates are constructed with electro-conductive material and the plates comprise a variable resistor. The resistance value across the plates changes as a function as to whether the plates are contacting, not contacting, or there is contamination between them. A converter circuit produces a resistive signal that is indicative of the resistance value of the variable resistor. Processing means receives the resistive signal and responsively determines whether the valve is operating within predetermined performance parameters. A signal may be produced to drive an indicator to show whether the valve is functioning properly.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: September 5, 2000
    Assignee: Caterpillar Inc.
    Inventor: Gary N. Boyer
  • Patent number: H1854
    Abstract: An inductive spool displacement sensor for determining the position or displacement of a spool within a particular hydraulic valve including a sensor housing having a cavity formed therein adapted for mounting within the hydraulic valve, the sensor housing being positioned such that at least a portion of the valve spool is disposed to enter the sensor cavity during certain operations of the valve. The sensor further includes a sensing coil wound about the housing cavity and a reference coil wound about the housing and spaced from the sensing coil, the inductance of the sensing coil being responsive to movement of the spool within the cavity and the inductance of the reference coil being responsive to the temperature of the fluid passing through the hydraulic valve. Based upon eddy current principles and because eddy currents are a function of material conductivity, the sensing coil, when energized, generates a signal indicative of that portion of the spool present within the housing cavity.
    Type: Grant
    Filed: December 28, 1998
    Date of Patent: July 4, 2000
    Assignee: Caterpillar Inc.
    Inventors: Timothy A. Boston, Bruce E. Unger