Patents by Inventor Michael P. Weirich

Michael P. Weirich 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: 5373697
    Abstract: A hydrostatic transaxle having a hydrostatic transmission includes a plate-like dump valve disposed between the transaxle housing or in a recess formed therein, adjacent a fluid conduit that connects the pump and motor of the transmission, the dump valve having fingers which unseat valves in the conduit to relief pressure therein. A rod having an offset portion extends through a bore in the dump valve, the rotation of the rod and offset portion urges the fingers of the plate-like dump valve towards or away from the conduit valves. The settling chamber disposed within the transmission includes protrusions upwardly projecting from the bottom of the chamber which trap particulates suspended in the hydraulic fluid that circulate through the system. A magnet is likewise disposed in the settling chamber adjacent the protrusions for attracting and holding magnetic particles and debris circulated by the hydraulic fluid.
    Type: Grant
    Filed: July 22, 1991
    Date of Patent: December 20, 1994
    Assignee: Tecumseh Products Company
    Inventors: Norman E. Jolliff, Michael P. Weirich
  • Patent number: 5177967
    Abstract: A hydrostatic transaxle includes a hydrostatic transmission with a pump and motor, the pump and motor each including a track ring radially surrounding a cylinder in which are disposed a plurality of pistons rotatable on a fixed conduit. The motor track ring includes radially extending lugs disposed 180.degree. from each other that are captured between the upper and lower transaxle casing halves thereby preventing axial or radial movement of the motor track ring.
    Type: Grant
    Filed: July 22, 1991
    Date of Patent: January 12, 1993
    Assignee: Tecumseh Products Company
    Inventors: Roland L. von Kaler, Dale I. Havens, Michael P. Weirich