Patents Assigned to Gresen Manufacturing Company
  • Patent number: 4310143
    Abstract: The present invention is an electrically controlled valve (10) that includes an elongated valve body (38) with an axial passageway (48) disposed along the elongation axis (44) thereof. The valve body (38) has at least one inlet passageway (52) and at least one outlet passageway (56, 58) in fluid communication with the axial passageway (48). The valve (10) includes structure (60, 62) for establishing a static magnetic field within the valve body and axial passageway. The valve member (90) is mounted within the axial passageway (48) for reciprocation therein to selectively establish fluid communication between the inlet and outlet passageways of the valve body. The valve member (90) has at least a portion thereof formed of material that is magnetizable and of relatively low permeability.
    Type: Grant
    Filed: August 15, 1980
    Date of Patent: January 12, 1982
    Assignee: Gresen Manufacturing Company
    Inventor: Roger G. Determan
  • Patent number: 4253482
    Abstract: A hydraulic valve of the type having a plurality of flow directing spools and valve bodies, normally disposed in a stack, or sectional control valve assembly, with registering like passageways on adjacent valve bodies in fluid communication. An open center pilot arrangement is provided to initially control the pressure of fluid supplied to an output passageway of an individual valve when its spool is moved to a position to supply fluid to a load connected thereto. A balanced flow control is disposed in each valve body between an inlet passageway and an outlet passageway and to a loop and an output passageway. The flow control is operative in response to the pressure in one of the output passageways of the valve body to control the proportionate flow of the fluid to the output passageway and the outlet passageway of the valve body. A number of individual valves may be operated in a stack in such a manner that an "upstream" valve will have "priority".
    Type: Grant
    Filed: March 5, 1979
    Date of Patent: March 3, 1981
    Assignee: Gresen Manufacturing Company
    Inventor: William T. Stephens
  • Patent number: 4195551
    Abstract: The disclosure is directed to an electromagnetic detent assembly for use with a manually operable hydraulic control valve to maintain the control spool in a predetermined limit position. The electromagnetic force created by the electromagnetic detent can be varied by an electronic circuit commensurate with the particular hydraulic application. A "feel" mechanism is also included, indicating to the operator that further manual movement of the control valve will cause it to reach the electromagnetic detent position.
    Type: Grant
    Filed: June 23, 1977
    Date of Patent: April 1, 1980
    Assignee: Gresen Manufacturing Company
    Inventor: Herbert H. Schmiel
  • Patent number: 4154262
    Abstract: The disclosure is directed to a closed center, pressure compensated hydraulic system which uses a multiple section hydraulic control valve in conjunction with a variable output hydraulic pump. The hydraulic control valve has a plurality of independently operable power spools each of which is used to control the flow of hydraulic fluid to a separate hydraulic actuator and load. Each valve section includes an automatic spool positioner which enables the operator to move the valve handle to a preselected position, the power spool thereafter being retained in such position until the actuator completes its stroke. After completion of the stroke, the automatic spool positioner causes the power spool to return to the neutral position. The multiple section hydraulic control valve also includes means for selecting the highest demand or work port pressure, and for controlling the variable output pump as a function of this selected pressure.
    Type: Grant
    Filed: October 17, 1977
    Date of Patent: May 15, 1979
    Assignee: Gresen Manufacturing Company
    Inventors: Nicholas C. Blume, Herbert H. Schmiel
  • Patent number: 4129987
    Abstract: The disclosure is directed to a closed center, pressure compensated hydraulic system which uses a multiple section hydraulic control valve in conjuction with a variable output hydraulic pump. The hydraulic control valve has a plurality of independently operable power spools each of which is used to control the flow of hydraulic fluid to a separate hydraulic actuator and load. Each valve section includes an automatic spool positioner which enables the operator to move the valve handle to a preselected position, the power spool thereafter being retained in such position until the actuator completes its stroke. After completion of the stroke, the automatic spool positioner causes the power spool to return to the neutral position. The multiple section hydraulic control valve also includes means for selecting the highest demand or work port pressure, and for controlling the variable output pump as a function of this selected pressure.
    Type: Grant
    Filed: October 17, 1977
    Date of Patent: December 19, 1978
    Assignee: Gresen Manufacturing Company
    Inventor: Nicholas C. Blume
  • Patent number: 4075933
    Abstract: A fluid pressure device comprising a pump or motor having a rotating internal assembly comprising linear pistons and cylinders operated through a "swash" plate to actuate the pistons to provide output pressure. The swash plate is mounted to the drive shaft through a universal connection and the cylinder and piston assemblies are coupled to their component parts through universal swiveling ball and socket connections. Special spring washers are provided for insuring a sliding seal between the internal cylinders and a valving plate, and the valve ports are designed for noise minimization.
    Type: Grant
    Filed: June 4, 1976
    Date of Patent: February 28, 1978
    Assignee: Gresen Manufacturing Company
    Inventor: William T. Stephens
  • Patent number: 4025243
    Abstract: An orbital device in which the effective roots of the internally extending teeth on an orbital member is equal to the radial dimension of the fluid ports. This is achieved by providing grooves in the surfaces of the orbital member adjacent the roots of the teeth. The shape of the ports is complimentary to that of the internal teeth on the orbital member.
    Type: Grant
    Filed: January 5, 1973
    Date of Patent: May 24, 1977
    Assignee: Gresen Manufacturing Company
    Inventor: William T. Stephens
  • Patent number: RE28933
    Abstract: A fluid operated device in which an externally toothed rotor is rotatably disposed in a chamber and an internally toothed member is orbitally but not rotatably disposed in the chamber about the rotor. The rotor and orbital member are operative upon relative rotation to form fluid containing pockets therebetween and suitable fluid ducts are provided for conveying fluid to and from the fluid containing pockets. The orbital member is provided with means to cooperatively engage the housing to limit, or prevent unidirectional rotational motion of the orbiting member but to allow orbital movement about the axis of rotation of the rotor.
    Type: Grant
    Filed: December 17, 1970
    Date of Patent: August 17, 1976
    Assignee: Gresen Manufacturing Company
    Inventor: Mortimer J. Huber