Patents Examined by Look Edward
  • Patent number: 5081902
    Abstract: For the relief of a highly pressurized hydraulic liquid in a working chamber of pilot controlled 2/2 poppet valve is used. The working chamber is further connected to a pressure relief valve, the output of which is connected to a control conduit extending between a control chamber of the 2/2 poppet valve and the pilot valve. The apparatus of the invention requires a shorter period of time for the pressure relief without the danger of relief noise.
    Type: Grant
    Filed: July 9, 1990
    Date of Patent: January 21, 1992
    Assignee: Mannesmann Rexroth GmbH
    Inventor: Georg Rausch
  • Patent number: 4353220
    Abstract: A method and apparatus for controlling a resonant piston compressor of the type comprising an electrodynamic linear reciprocating motor adapted to be driven cyclically by an alternating current power source and having at least one piston coupled to and adapted to be driven within a selectively valved working cylinder by the linear reciprocating motor in synchronism with the frequency of the alternating current power source. Enclosed volumes of gas act as resilient gas springs coacting with the piston and with the linear reciprocating motor to form a mechanical resonant system having a resonant frequency substantially centered on the frequency of the alternating current power source. A midstroke porting arrangement is responsive to the position of the resonant piston for selectively communicating a gas spring control valve with said gas springs.
    Type: Grant
    Filed: June 17, 1980
    Date of Patent: October 12, 1982
    Assignee: Mechanical Technology Incorporated
    Inventors: Peter W. Curwen, Richard A. Dorman