Patents Assigned to Terra Drive Systems, Inc.
  • Patent number: 10889322
    Abstract: An oscillation limited driven steering track assembly includes a track mechanism coupled to and driven by a hydraulic motor. The motor is pivotally secured about a steering axis to a stub axle which partially supports a land vehicle. A longitudinally extensible and retractable apparatus extends between the track mechanism and the stub axle. One end of the apparatus is pivotally secured to a post secured to and extending from the track mechanism parallel with the motor shaft axis of rotation. A yoke is provided between the apparatus other end and pivotally secures the apparatus to the stub axle about the steering axis and, also, about a pivot axis perpendicular to the steering axis. Oscillation of the track mechanism about the motor shaft is limited by the apparatus. Simultaneously, the apparatus does not interfere with the track mechanism while the mechanism is rotated about the steering axis for steering the vehicle.
    Type: Grant
    Filed: July 30, 2018
    Date of Patent: January 12, 2021
    Assignee: Terra Drive Systems, Inc.
    Inventor: Kasandra Coverdale
  • Publication number: 20200031391
    Abstract: An oscillation limited driven steering track assembly includes a track mechanism coupled to and driven by a hydraulic motor. The motor is pivotally secured about a steering axis to a stub axle which partially supports a land vehicle. A longitudinally extensible and retractable apparatus extends between the track mechanism and the stub axle. One end of the apparatus is pivotally secured to a post secured to and extending from the track mechanism parallel with the motor shaft axis of rotation. A yoke is provided between the apparatus other end and pivotally secures the apparatus to the stub axle about the steering axis and, also, about a pivot axis perpendicular to the steering axis. Oscillation of the track mechanism about the motor shaft is limited by the apparatus. Simultaneously, the apparatus does not interfere with the track mechanism while the mechanism is rotated about the steering axis for steering the vehicle.
    Type: Application
    Filed: July 30, 2018
    Publication date: January 30, 2020
    Applicant: Terra Drive Systems, Inc.
    Inventor: Kasandra Coverdale
  • Patent number: 9387881
    Abstract: A land vehicle steering system capable of selectively moving the left and right steerable wheels inboard and outboard of the vehicle, and selectively adjusting the distance between the left and right steerable wheels. The steering system includes left and right steering assemblies. Each assembly includes: a pivot arm pivotally secured to the vehicle about a first pivot axis; a first hydraulic cylinder secured between the pivot arm and the vehicle; a wheel end pivotally secured to the pivot arm about a steering axis; and, a second hydraulic cylinder secured between the wheel end and the pivot arm. Actuation of the first hydraulic cylinders rotates the pivot arms about their first pivot axes and moves the wheel ends inboard and outboard of the vehicle. Actuation of the second hydraulic cylinders rotates the wheel ends and steerable wheels thereon relative to their pivot arm for steering the vehicle.
    Type: Grant
    Filed: November 18, 2013
    Date of Patent: July 12, 2016
    Assignee: Terra Drive Systems, Inc.
    Inventors: James A. Smith, James L. Jackson, Daniel Pitstick
  • Patent number: 8813487
    Abstract: A hydraulic circuit for a vehicle includes a first loop that includes, in serial order, a first hydraulic pump, a first hydraulic line, a hydraulic motor and a second hydraulic line. A second hydraulic pump and a third valve control low pressure fluid from the second pump to the hydraulic motor casing. The low pressure fluid through the third valve maintains the motor pistons retracted when the motor is not being used. For actuating the motor, the third valve is actuated for disconnecting the second pump and relieving pressure from the motor casing. Low pressure is then provided to the first and second lines for extending the motor pistons. The first and second valves are then actuated for isolating the first and second lines from one another, and the first pump is used to power the motor. The first, second and third valves are advantageously solenoid cartridge valves.
    Type: Grant
    Filed: September 6, 2012
    Date of Patent: August 26, 2014
    Assignee: Terra Drive Systems, Inc.
    Inventors: Keith M. Mears, James E. Smith, Brad A. Meyerholtz
  • Patent number: 8276376
    Abstract: A hydraulic circuit for a vehicle having at least one selectively actuated hydraulic assist motor. The hydraulic circuit includes a first loop that includes, in serial order, a first hydraulic pump, a first hydraulic line, at least one hydraulic motor and a second hydraulic line. A second hydraulic pump and a third valve is used to control the flow of low pressure fluid from the second pump to the hydraulic motor casing. The low pressure fluid through the third valve maintains the motor pistons retracted when the motor is not being used. For actuating the motor, the third valve is actuated for disconnecting the second pump and relieving pressure from the motor casing. Low pressure is then provided to the first and second lines for extending the motor pistons. The first and second valves are then actuated for isolating the first and second lines from one another, and the first pump is used to power the motor. The first, second and third valves are advantageously solenoid cartridge valves.
    Type: Grant
    Filed: May 6, 2009
    Date of Patent: October 2, 2012
    Assignee: Terra Drive Systems, Inc.
    Inventors: Keith M. Mears, James E. Smith, Brad A. Meyerholtz
  • Patent number: 8230772
    Abstract: A spindle body defining a central axis and having a hydraulic motor assembly operably mounted thereon. At least a portion of the hydraulic motor assembly is rotatable relative to the spindle body about the central axis. A plurality of hydraulic passages extend within the spindle body. Each of the passages includes axial and lateral sections. The axial sections are in fluid communication with the hydraulic motor assembly and define a first centerline extending substantially parallel with the central axis. Each of the lateral sections are in fluid communication with one of the axial sections and form a port on an outer surface of the spindle body. The lateral sections also each define a second centerline wherein the second centerlines are positioned in mutually parallel planes and each of the first centerlines and the central axis are substantially parallel with each of the mutually parallel planes. A method of manufacture is also disclosed.
    Type: Grant
    Filed: March 5, 2009
    Date of Patent: July 31, 2012
    Assignee: Terra Drive Systems, Inc.
    Inventor: Lane C. Kirby