Symmetrical rotary pump for a variable speed hydrostatic transmission

Claim 2

A symmetrical rotary pump comprising a housing; a hollow cylindrical rotor having a main portion and an extension portion at each end thereof, the rotor being situated rotatably within the housing; mounting means for receiving each of the said extension portions rotatably therein; means for moving the mounting means radially of the axis of the rotor to thereby move the rotor in a radial direction; an input shaft extending longitudinally through the housing and through the interior of the rotor; a plurality of vanes freely pivoted on the shaft and extending slidably through the main portion of the rotor; transmission means comprising a wheel fixed to the input shaft adjacent the main portion of the rotor, the wheel having a plurality of resilient teeth extending radially outwardly and engaging portions of the vanes located inwardly of the rotor for providing a driving connection between the shaft and the rotor; input conduit means for supplying fluid to the pump; and output conduit means for taking fluid away from the pump.

Claim 3

A symmetrical rotary pump comprising a housing; a hollow cylindrical rotor having a main portion and an extension portion at each end thereof, wherein at least one of the said extension portions has a pair of segments extending longitudinally outwardly therefrom, the rotor being situated rotatably within the housing; mounting means for receiving each of the said extension portions rotatably therein; means for moving the mounting means radially of the axis of the rotor to thereby move the rotor in a radial direction; an input shaft extending longitudinally through the housing and through the interior of the rotor; a plurality of vanes freely pivoted on the shaft and extending slidably through the main portion of the rotor; transmission means comprising an annulus surrounding the segments, a sleeve secured to the shaft at a location radially inwardly of the annulus, a pair of pins passing slidably through respective apertures in the annulus and fixedly recEived by the sleeve, and a further pair of pins passing slidably through respective apertures in the annulus and fixedly received by the segments; providing a driving connection between the shaft and the rotor; input conduit means for supplying fluid to the pump; and output conduit means for taking fluid away from the pump.

Claim 4

A symmetrical rotary pump comprising a housing; a hollow cylindrical rotor having a main portion and an extension portion at each end thereof, wherein at least one of the said extension portions has a pair of segments extending longitudinally outwardly therefrom, the rotor being situated rotatably within the housing; mounting means for receiving each of the said extension portions rotatably therein; means for moving the mounting means radially of the axis of the rotor to thereby move the rotor in a radial direction; an input shaft extending longitudinally through the housing and through the interior of the rotor; a plurality of vanes freely pivoted on the shaft and extending slidably through the main portion of the rotor; transmission means comprising an annulus surrounding the segments, a sleeve secured to the shaft at a location radially inwardly of the annulus, a pair of pins passing slidably through respective apertures in the annulus and fixedly recEived by the sleeve, and a further pair of pins passing slidably through respective apertures in the annulus and fixedly received by the segments; providing a driving connection between the shaft and the rotor; input conduit means for supplying fluid to the pump; and output conduit means for taking fluid away from the pump.

Claim 5

A symmetrical rotary pump comprising a housing; a hollow cylindrical rotor having a main portion and an extension portion at each end thereof, the rotor being situated rotatably within the housing; mounting means for receiving each of the said extension portions rotatably therein; means for moving the mounting means radially of the axis of the rotor to thereby move the rotor in a radial direction; an input shaft extending longitudinally through the housing and through the interior of the rotor; a plurality of vanes freely pivoted on the shaft and extending slidably through the main portion of the rotor; transmission means providing a driving connection between the shaft and the rotor; input conduit means for supplying fluid to the pump; output conduit means for taking fluid away from the pump, and a further conduit extending between the input conduit and the output conduit, the said further conduit slidably receiving a piston therein, the piston being resiliently biased to a mean position and acting to compensate for pulsations in pump output.

Claim 6

A symmetrical rotary pump comprising a housing; a hollow cylindrical rotor having a main portion and an extension portion at each end thereof, the rotor being situated rotatably within the housing; mounting means for receiving each of the said extension portions rotatably therein; means for moving the mounting means radially of the axis of the rotor to thereby move the rotor in a radial direction; an input shaft extending longitudinally through the housing and through the interior of the rotor; a plurality of vanes freely pivoted on the shaft and extending slidably through the main portion of the rotor; transmission means providing a driving connection between the shaft and the rotor; input conduit means for supplying fluid to the pump; output conduit means for taking fluid away from the pump, and a further conduit extending between the input conduit and the output conduit, the said further conduit slidably receiving a piston therein, the piston being resiliently biased to a mean position and acting to compensate for pulsations in pump output.

Claim 7

A rotary pump according to claim 3, wherein a relief conduit interconnects the input conduit and the output conduit, a relief valve being situated in the relief conduit and being adapted to open in the event of excessive pressure in either conduit thereby to relieve the said excessive pressure.