Patent ID: 9091040
Filing Date: 2015-07-28
Classification: E02F,F01P,F16H

Abstract:
1. A hydraulic circuit comprising: a primary pump; a displacement actuator associated with the primary pump; a charge pump configured to generate a flow of a pilot fluid; a direction control valve configured to control the flow of the pilot fluid to the displacement actuator to affect a movement direction of the displacement actuator; a pressure control valve configured to control a pressure of the pilot fluid to affect a movement amount of the displacement actuator; a motor; a fan connected to and driven by the motor; a high pressure passage fluidly connected between the motor and the primary pump; a low pressure passage fluidly connected between the motor and the primary pump; at least one accumulator in selective fluid communication with at least one of the high- and low- pressure passages; a fan isolation valve connected between the high pressure passage and the motor, and between the low pressure passage and the motor, the fan isolation valve being configured to selectively isolate portions of the high and low pressure passages between the fan isolation valve and the motor; a motor flushing valve selectively connected between the isolated portions of the high and low pressure passages and a low pressure sump; and a controller being configured to control the direction and the pressure control valves to adjust a displacement of the primary pump based at least on one of a sensed engine parameter or a mode of operation of the primary pump.