Patents by Inventor Emerl R. Carpenter

Emerl R. Carpenter 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: 3960284
    Abstract: A hydraulic backhoe utilizes two pairs of hydraulic pumps to power independent crawler track drives in any forward or reverse direction, and high or low speed ranges; allowing, for example, a wide arc turn either left or right, forward or backward. Through a novel hydraulic circuit, these pumps also power other functions such as boom, bucket and stick drives in high speed or low speed modes. This flexibility is accomplished by the use of a manually controlled track speed selector valve, an unloading valve and check valve between a track function valve and another function valve in each of the two hydraulic circuits. Full hydraulic pressure is available to all functions at all times except when a track drive is in high speed range. Conventional high-low or unloading operation of the other functions is had when the related track drive is not operating.
    Type: Grant
    Filed: April 7, 1975
    Date of Patent: June 1, 1976
    Assignee: American Hoist & Derrick Company
    Inventor: Emerl R. Carpenter