By Means Sensing Rotational Speed Of Output Motor Patents (Class 60/448)
  • Patent number: 3987624
    Abstract: A hydraulic drive control system for driving a generator or alternator or the like at a constant RPM regardless of variations in the output load or the input load comprising a driven pump having a variable volume and variable pressure output connected in a closed system to a hydraulic motor which will maintain a constant RPM output, regardless of the RPM's of the driving means, which is coupled to the device to be driven. Connected between the pump and the motor is a volume control line having a volume control valve which insures that the volume of fluid to the hydraulic motor will be constant thus providing a constant line RPM output of the driving motor, and a pressure regulating line connected between said pump and said motor to regulate the pump pressure output to insure that the motor RPM is constant although the load on the motor may vary. The volume control valve regulates hydraulic fluid between the pump and motor regardless of the pressure and volume output of the pump.
    Type: Grant
    Filed: June 23, 1975
    Date of Patent: October 26, 1976
    Inventors: George H. Cooke, A. Edward Appleby
  • Patent number: 3983700
    Abstract: This disclosure relates to a fluid transmission for automatically varying the drive ratio in accordance with the load placed thereon and includes a pump unit and a motor unit and wherein the pump unit is of a variable displacement with the displacement thereof being automatically adjustable in accordance with the pressure of the fluid output thereof and the input speed of the pump unit. The pump unit is of the radial piston type and includes a race member engaged by the pistons for controlling the displacement thereof. The race member has a cylindrical race surface and is mounted for tilting movement wherein in a neutral position the pistons have zero displacement and wherein when the race member is tilted, the displacement of the pistons increases.
    Type: Grant
    Filed: December 20, 1974
    Date of Patent: October 5, 1976
    Inventor: George M. Barrett
  • Patent number: 3978668
    Abstract: The transmission drives a dispensing apparatus at a speed varying in proportion to a command value furnished by a command device. The transmission includes a hydromotor driving the dispensing apparatus, a main pump driving the hydromotor, and a regulating arrangement for making the variations in the speed of the hydromotor proportional to the variations in the command value. The regulating arrangement includes first and second measuring pumps driven by the hydromotor and by the command device for generating control pressures respectively indicative of the hydromotor speed and the command value. The regulating arrangement further includes a hydraulic control device connected to receive the control pressures and operative for automatically varying the fluid output of the main pump in dependence upon the difference in the control pressures.
    Type: Grant
    Filed: October 10, 1972
    Date of Patent: September 7, 1976
    Assignee: Robert Bosch G.m.b.H.
    Inventor: Gerhard Nonnenmacher
  • Patent number: 3943713
    Abstract: A hoist system employing a hydraulic motor, a variable displacement reversible flow hydraulic pump for supplying hydraulic fluid to the hydraulic motor, and an electric motor employed as a prime mover for the pump has a control arrangement effective for sensing various indicia of operation as, for example, rate of speed of lifting of an associated load, failure of the hoist system power train and the lifting of maximum loads. Within the overall control arrangement means are provided for comparing the actual rate of speed of lifting to the desired or requested rate of speed of lifting with the differential thereof being directed back to the associated mechanism for varying the output displacement of said hydraulic pump for thereby modifying such output displacement in order to achieve zero differential output. Means are also provided for automatically braking the hoist drum in order to prevent the load carried thereby from dropping in the event of a failure of the said power train.
    Type: Grant
    Filed: November 25, 1974
    Date of Patent: March 16, 1976
    Assignee: Eaton Corporation
    Inventor: Erlen B. Walton