Patent classifications
F16H61/4157
Method and system for controlling a hydrostatic drive system of an agricultural vehicle
In ore aspect, a method is provided or braking a work vehicle including an engine and a hydrostatic drive system including a hydraulic pump configured to be rotationally driven by the engine and a hydraulic motor fluidly coupled with the hydraulic pump through a closed hydraulic loop of the hydrostatic drive system. The hydraulic pump may be configured to fluidly drive the hydraulic motor. The method may include receiving an operator request to reduce a ground speed of the work vehicle. The method may include monitoring a fluid temperature of a hydraulic fluid associated with the closed hydraulic loop and automatically controlling at least one of a pump displacement of the hydraulic pump or a motor displacement of the hydraulic motor based on the operator request and the monitored fluid temperature to adjust hydrostatic braking of the work vehicle and thereby reduce the ground speed of the work vehicle.
Method and system for controlling a hydrostatic drive system of an agricultural vehicle
In ore aspect, a method is provided or braking a work vehicle including an engine and a hydrostatic drive system including a hydraulic pump configured to be rotationally driven by the engine and a hydraulic motor fluidly coupled with the hydraulic pump through a closed hydraulic loop of the hydrostatic drive system. The hydraulic pump may be configured to fluidly drive the hydraulic motor. The method may include receiving an operator request to reduce a ground speed of the work vehicle. The method may include monitoring a fluid temperature of a hydraulic fluid associated with the closed hydraulic loop and automatically controlling at least one of a pump displacement of the hydraulic pump or a motor displacement of the hydraulic motor based on the operator request and the monitored fluid temperature to adjust hydrostatic braking of the work vehicle and thereby reduce the ground speed of the work vehicle.
Hydrostatic Traction Drive in an Open Circuit
A hydrostatic traction drive includes a hydrostatic pump and a hydrostatic motor connected to each other in an open circuit. One of the pump and motor is pressure-regulated while the other is torque-controlled or regulated in terms of pivot angle. A braking mode is therefore possible in which the secondary-side braking torque can be adapted to the permissible primary-side supporting torque of a primary machine coupled to the pump. To further increase the braking power, even in a high rotational phase of the primary machine, the permissible drag torque thereof can be temporarily exceeded. To further increase the braking power and therefore to have high-performance braking during operation, further means for converting energy can be provided in order to adjust a secondary-side braking torque and a primary-side supporting torque independently of each other.
Hydrostatic Traction Drive in an Open Circuit
A hydrostatic traction drive includes a hydrostatic pump and a hydrostatic motor connected to each other in an open circuit. One of the pump and motor is pressure-regulated while the other is torque-controlled or regulated in terms of pivot angle. A braking mode is therefore possible in which the secondary-side braking torque can be adapted to the permissible primary-side supporting torque of a primary machine coupled to the pump. To further increase the braking power, even in a high rotational phase of the primary machine, the permissible drag torque thereof can be temporarily exceeded. To further increase the braking power and therefore to have high-performance braking during operation, further means for converting energy can be provided in order to adjust a secondary-side braking torque and a primary-side supporting torque independently of each other.
Hydrostatically driven vehicle with a secondary braking or steering supply
The hydraulic braking or steering system of a vehicle driven by a hydraulic motor is provided with a secondary supply of hydraulic pressure in the event of failure of the primary supply to the system. The secondary supply is generated by the hydraulic motor when ground-driven by the momentum of the moving vehicle.
Hydrostatically driven vehicle with a secondary braking or steering supply
The hydraulic braking or steering system of a vehicle driven by a hydraulic motor is provided with a secondary supply of hydraulic pressure in the event of failure of the primary supply to the system. The secondary supply is generated by the hydraulic motor when ground-driven by the momentum of the moving vehicle.
Hydraulic system of work machine and work machine
A hydraulic system of a work machine includes a first hydraulic device to operate in a first operation mode while pressure of hydraulic oil supplied from a hydraulic pump via a first oil passage is equal to or higher than a first pressure threshold. The hydraulic oil in the first oil passage is to be discharged via a second oil passage. A pilot check valve is provided in the second oil passage and has a pilot port to receive a pilot pressure of the hydraulic oil. The pilot check valve is closed to stop discharging the hydraulic oil in the first oil passage through the second oil passage while the pilot pressure is lower than the fourth pressure threshold. The pilot check valve is opened while the pilot pressure is higher than or equal to the fourth pressure threshold. The first hydraulic device is a ride control device.
Hydraulic braking energy utilization for emergency steering, braking, charging accumulator(s), and/or work functions to reduce or prevent engine from overspeed, assist acceleration and/or unlimited towing
A system and method configured to direct the braking energy from a high-pressure port at the motor side of a hydraulic circuit to emergency steering, braking, accumulator(s) charging, and/or various work functions. The system and method are also configured to return hydraulic fluid back to the same high-pressure port when the motor is running as a pump.
Hydraulic braking energy utilization for emergency steering, braking, charging accumulator(s), and/or work functions to reduce or prevent engine from overspeed, assist acceleration and/or unlimited towing
A system and method configured to direct the braking energy from a high-pressure port at the motor side of a hydraulic circuit to emergency steering, braking, accumulator(s) charging, and/or various work functions. The system and method are also configured to return hydraulic fluid back to the same high-pressure port when the motor is running as a pump.
Overrun protection for wind turbines
A braking system for a turbine of a wind powered includes a hydraulic machine connected to a drive shaft of the turbine. A pressure regulating valve in the supply line of the hydraulic machine determines the pressure delivered to the supply line by the hydraulic machine. A control that is responsive to the speed of rotation of the drive shaft modulates the pressure regulating valve so as to increase pressure in the supply line as the rotational speed exceeds a predetermined speed to apply a braking force to the drive shaft.