Electro-hydraulic system for fan driving and brake charging
AssigneeCaterpillar Inc.
InventorsXiaodong Huang, Rabie Khalil, John Krone
Life of this patent
Estimating the term…
Abstract
An electro-hydraulic system for a machine may include a brake charging system including at least one accumulator. A fan drive system may include a fan and a fan motor. A fluid source may be in communication with the brake charging system and the fan drive system. The fluid source may be configured to provide pressurized fluid to the brake charging system and the fan drive system to charge at least one accumulator and to drive a fan motor. A priority valve may be configured to provide pressure from the fluid source to the brake charging system, such that the fluid pressure at the accumulator is maintained at a substantially constant level during normal operating conditions.
Claims27
An electro-hydraulic system for a machine comprising:
- a brake charging system including at least one accumulator configured to store fluid pressure for brake control;
- a fan drive system including a fan and a fan motor, the fan motor being configured to turn the fan;
- a fluid source in communication with the brake charging system and the fan drive system, the fluid source being configured to provide pressurized fluid to the brake charging system and the fan drive system to charge the at least one accumulator and to drive the fan motor;
- and
- a priority valve configured to provide pressure from the fluid source to the brake charging system, such that the fluid pressure at the accumulator is maintained at a substantially constant level during normal operating conditions.
An electro-hydraulic system for a machine comprising:
- a brake charging system including at least one accumulator configured to store fluid pressure for brake control;
- a fan drive system including a fan and a fan motor, the fan motor being configured to turn the fan;
- a fluid source in communication with the brake charging system and the fan drive system, the fluid source being configured to provide pressurized fluid to the brake charging system and the fan drive system to charge the brake system and to drive the fan motor;
- a priority valve disposed between the fluid source and the brake charging system and also disposed between the fluid source and the fan drive system, the priority valve being configured to permit flow sharing between the brake charging system and the fan drive system.
A method of operating an electro-hydraulic system for a machine, comprising:
- directing fluid to a brake charging system including at least one accumulator configured to store fluid pressure for brake control;
- directing fluid to a fan drive system including a fan and a fan motor, the fan motor being configured to turn the fan;
- providing pressurized fluid to the brake charging system and the fan drive system with a fluid source to charge the at least one accumulator and to drive the fan motor;
- and
- maintaining the fluid pressure at the accumulator at a substantially constant level during normal operating conditions.
A method of operating an electro-hydraulic system for a machine, comprising:
- directing fluid to a fan drive system including a fan and a fan motor, the fan motor being configured to turn the fan;
- providing pressurized fluid to the fan drive system with a fluid source to drive the fan motor;
- reducing a rotational speed of the fan below a pre-established threshold;
- and
- activating a reversing valve configured to reverse the rotational direction of the fan.
Dependencies are inferred from the claim text.