초록 ▼

A flushing system for a transmission is disclosed. The system has a first pump and a first actuator connected to the first pump to form a first loop. The system also has a second pump and a second actuator connected to the second pump to form a second loop. The system further has a charge pump confi

A flushing system for a transmission is disclosed. The system has a first pump and a first actuator connected to the first pump to form a first loop. The system also has a second pump and a second actuator connected to the second pump to form a second loop. The system further has a charge pump configured to replenish the first and second loops. The system also has a single charge relief valve situated to receive fluid from the first pump, the second pump, and the charge pump.

대표청구항 ▼

What is claimed is: 1. A flushing system for a transmission, comprising: a first pump; a first motor connected to the first pump to form a first loop; a second pump; a second motor connected to the second pump to form a second loop; a charge pump configured to replenish the first and second loops;

What is claimed is: 1. A flushing system for a transmission, comprising: a first pump; a first motor connected to the first pump to form a first loop; a second pump; a second motor connected to the second pump to form a second loop; a charge pump configured to replenish the first and second loops; a neutral bypass valve configured to receive fluid from the charge pump; and a charge relief valve situated to receive fluid from the first loop, the second loop, and the neutral bypass valve. 2. The flushing system of claim 1, further including a first flushing valve fluidly connected to the first loop and a second flushing valve fluidly connected to the second loop, the first and second flushing valves being in fluid communication with the charge relief valve. 3. The flushing system of claim 2, wherein the first and second flushing valves are pilot-operated. 4. The flushing system of claim 3, wherein the first loop includes two passages connecting the first pump with the first flushing valve and the first motor and a higher pressure of the two passages controls the motion of the first flushing valve. 5. The flushing system of claim 1, further including a plurality of check valves fluidly connecting the charge pump to the first and second loops. 6. The flushing system of claim 5, wherein the plurality of check valves includes a first plurality of check valves connecting the charge pump to the first loop, and a second plurality of check valves connecting the charge pump to the second loop. 7. The flushing system of claim 6, wherein: the first and second pumps are over-center pumps; and the first plurality of check valves includes at least one check valve always in fluid communication with a low pressure side of the first pump. 8. The flushing system of claim 1, further including a common sump fluidly connected to the first pump, the second pump, and the charge pump. 9. The flushing system of claim 1, wherein, when in a neutral state, fluid from only the charge pump passes through the charge relief valve. 10. The flushing system of claim 1, wherein, the neutral bypass valve is a spring loaded check valve. 11. A vehicle, comprising: a power source; and a transmission powered by the power source to propel the vehicle, the transmission comprising: a first over-center pump; a first motor connected to the first over-center pump to form a first closed loop; a second over-center pump; a second motor connected to the second over-center pump to form a second closed loop; a charge pump configured to replenish the first and second closed loops; a neutral bypass valve configured to receive fluid from the charge pump; and a single charge relief valve situated to receive fluid from the first over-center pump, the second over-center pump, and the neutral bypass valve. 12. The vehicle of claim 11, further including a first flushing valve fluidly connected to the first loop and a second flushing valve fluidly connected to the second loop, the first and second flushing valves being in fluid communication with the charge relief valve. 13. The vehicle of claim 12, wherein the first and second flushing valves are pilot-operated. 14. The vehicle of claim 11, wherein, the neutral bypass valve is a spring loaded check valve.