Hydraulic drive system for turf maintenance equipment unit
AssigneeThe Toro Company
InventorRichard J. Guertin
Life of this patent
Estimating the term…
Abstract
A turf maintenance equipment unit, such as a riding mower having two side cutting units and a front cutting unit operatively connected to a traction frame. A hydraulic traction system is provided for propelling the traction frame in forward and reverse. This traction system includes a pair of front drive motors and a rear drive motor connected in parallel to a pump. A pressure reducing device limits fluid pressure to the rear drive motor when the traction frame is moving in reverse to increase the climbing ability of the traction frame in reverse.
Claims14
A turf maintenance equipment unit, which comprises:
- (a) a traction frame capable of movement over the ground;
- (b) at least one turf maintenance operating unit coupled to the frame;
- (c) a hydraulic traction system for powering the traction frame, the traction system comprising a source of pressurized fluid, at least one front drive motor powering at least one front drive wheel on the traction frame, and at least one rear drive motor powering at least one rear drive wheel on the traction frame, the front and rear drive motors being connected in parallel to the source of pressurized fluid by a fluid path that provides full pump flow to the front and rear drive motors in both forward and reverse directions;
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- (d) a pressure reducing device for supplying the at least one rear drive motor with full pump flow at different maximum pressures during forward and reverse motions of the traction frame.
A turf maintenance equipment unit, which comprises:
- (a) a traction frame capable of movement over the ground, the traction frame having a pair of front drive wheels and at least one rear drive wheel;
- (b) at least one turf maintenance operating unit coupled to the frame;
- (c) a hydraulic traction system for powering the traction frame, the traction system comprising a source of pressurized fluid, at least one front drive motor powering at least one front drive wheel on the traction frame, and a single rear drive motor powering at least one rear drive wheel on the traction frame, the front and rear drive motors being connected in parallel to the source of pressurized fluid by a fluid path that provides fluid at a predetermined maximum pressure to the front and rear drive motors during forward motion of the traction frame such that the fluid is available at the predetermined maximum pressure to all of the front and rear drive motors during forward motion of the traction frame, the fluid path including fluid supply lines which transport fluid from the source of pressurized fluid to the front and rear drive motors and fluid return lines which return fluid from the front and rear drive motors to the source of pressurized fluid during forward motion of the traction frame;
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- (d) a single check valve and pressure reducing device placed in the return line from the rear drive motor and arranged to supply only the rear drive motor with fluid at less than the predetermined maximum pressure during reverse motion of the traction frame while the fluid path continues to supply the at least one front drive motor with fluid at the predetermined maximum pressure during reverse motion of the traction frame.
Dependencies are inferred from the claim text.