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US 9,788,482 B2Granted
Grass mowing machine with hydraulic circuit having diverter valve
AssigneeDeere & Company
InventorsPaul A. Boruff, Brent G. Rinholm
Life of this patent
Estimating the term…
Abstract
A grass mowing machine has a plurality of cutting units, and a diverter valve diverting hydraulic flow from a raise/lower sub-circuit to a mowing sub-circuit when the engine runs at a reduced or economy mode speed and the cutting units are at the lowered position.
Claims11
A grass mowing machine having a plurality of cutting units, comprising:
- an internal combustion engine that runs at a normal engine speed or at an economy mode speed slower than the normal engine speed;
- the engine driving hydraulic pumps connected to a hydraulic circuit having a plurality of sub-circuits including a mowing sub-circuit to rotate the cutting units and a raise/lower sub-circuit to move the cutting units between a raised position and a lowered position;
- a diverter valve diverting hydraulic flow from the raise/lower sub-circuit to the mowing sub-circuit whereby the cutting units continue to rotate at a desired speed when the engine is switched to the economy mode speed and the cutting units are at the lowered position.
A grass mowing machine having a plurality of cutting units, comprising:
- a hydraulic circuit having a raise/lower sub-circuit connected to an operator actuated raise/lower lever to move the cutting units between a raised position and a lowered position, and a mowing sub-circuit for rotating a motor on each of the cutting units;
- and
- an electronic vehicle control unit actuating a diverter valve diverting hydraulic flow from the raise/lower sub-circuit to the mowing sub-circuit so that the cutting unit motors rotate at a desired speed if the electronic vehicle control unit detects a reduction in engine speed and the cutting units in the lowered position.
A grass mowing machine having a plurality of cutting units, comprising:
- an electronic vehicle control unit signal connected to an internal combustion engine and a raise/lower lever to raise and lower the cutting units;
- and
- a diverter valve actuated by the electronic vehicle control unit to increase hydraulic flow to a hydraulic motor on each cutting unit whereby the hydraulic motors continue to operate at a desired speed when the engine speed is reduced to an economy mode speed and the raise/lower lever is in a lowered position.
Dependencies are inferred from the claim text.