Patents Examined by Abraham Hershkevitz
  • Patent number: 3986438
    Abstract: A double-acting hydraulic cylinder includes a hollow cylinder body with a closed end and an end with a first rod opening. A first hollow piston and rod assembly, having a second rod opening at the piston end, projects through the first rod opening and slides in the cylinder body. A second hollow piston and rod assembly, secured at the rod end to the hollow cylinder body, projects through the second rod opening and slides in the first hollow piston and rod assembly. The first and second hollow piston and rod assemblies cooperate to form a first variable volume chamber. A rod secured to the rod end of the first hollow piston and rod assembly slidably projects into the second hollow piston and rod assembly and cooperates therewith to form a second variable volume chamber. The first variable volume chamber is connected to a first port in the cylinder body and is expandable and contractable in response respectively to retraction and extension of the first hollow piston and rod assembly.
    Type: Grant
    Filed: September 8, 1975
    Date of Patent: October 19, 1976
    Assignee: Deere & Company
    Inventor: Richard Arthur Wittren