Patents by Inventor Charles R. Ellmers

Charles R. Ellmers 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).

  • Free delivery return valve and associated system
    Patent number: 4148337
    Abstract: A free delivery controlled return valve, of the type employed in fluid power hoisting apparatus, which controls the speed at which a load is lowered as a function of load magnitude. An improved valve structure is disclosed which overcomes false load signals, such as those generated when the hoisting apparatus' lift cylinders are fully extended against a stop, and which thus permits the load platform to descend at an appropriate speed. An improved fluid sonic muffler is also disclosed.
    Type: Grant
    Filed: February 8, 1977
    Date of Patent: April 10, 1979
    Assignee: Fluid Controls, Inc.
    Inventor: Charles R. Ellmers