摘要:
An adaptive automatic transmission control system responds to stopping of a vehicle for reducing torque absorption by an automatic transmission and movement of and range to obstructions forward from a vehicle for reengaging the automatic transmission after a stop. The torque converter is released from its reduced torque absorption mode under one of three circumstances: 1) the brake pedal is released; 2) the detected obstruction moves outside a first predefined maximum range; and, 3) the detected obstruction moves outside a second predefined maximum range and at greater than a predefined minimum speed.
摘要:
An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.
摘要:
An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.
摘要:
A work vehicle includes a hydrostatic continuously variable speed-change device, a gear type multiple-stage speed-change device disposed downstream of the hydrostatic continuously variable speed-change device with respect to a direction in which power is transmitted, first and second oil passages, a bypass oil passage communicating the first and second oil passages with each other, a valve mechanism for opening and closing the bypass oil passage, and a manual operating member provided in a driving section for opening and closing the valve mechanism.
摘要:
A travel operation structure of a work vehicle, comprising a pair of left and right side brake pedals disposed on either the left or right of a steering wheel; a hydro static transmission for changing the speed of travel; and a stop operation pedal disposed on the other of the left and right of the steering wheel; wherein the corresponding left or right side brake is applied when one of the pair of left and right side brake pedals is depressed, and when both the left and right side brake pedals are depressed, both the left and right side brakes operate, and travel is stopped; and when the stop operation pedal is depressed, operating oil of the continuously variable speed change device is directed into an oil tank, and the continuously variable speed change device is switched to a neutral stop position for blocking transmission of power to the travel device.
摘要:
When the driver makes a request for switching the shift range to the P range despite that the vehicle has not yet stopped completely, the wheel cylinder pressure is maintained at a brake hold pressure Ph for a while, rather than switching the shift range to the P range immediately. At this time, more specifically, the wheel cylinder pressure is maintained at the brake hold pressure Ph for a brake hold duration Δt within which the vehicle is estimated to stop, and when the brake hold duration Δt has passed, the shift range is switched to the P range. After the lock mechanism is actuated to establish the P range, the wheel cylinder pressure is gradually reduced from the brake hold pressure Ph at a given pressure reducing gradient.
摘要:
A control system for an automatic transmission includes a clutch adapted to be applied when a forward running range is selected, for transmitting the rotation of an engine to a speed change unit. A hydraulic servo applies the clutch responsive to feed of an oil pressure and a control unit controls the oil pressure fed to the hydraulic servo. The control unit brings the clutch into a substantially released state by lowering the oil pressure of the hydraulic servo if the stop state of a vehicle is detected by a stop state detector and applies the clutch if the stop state of the vehicle is not detected with the clutch released. The oil pressure fed to the hydraulic servo is raised according to a second mode when the accelerator pedal is depressed, in preference to a first mode in which a brake pedal is released, if the accelerator pedal is depressed when the stop state of the vehicle is not detected because the accelerator pedal is released so that the engagement of the clutch has not started.
摘要:
In a creep preventing device of the type in which an oil discharge passage communicating with an oil tank is branched from an oil feed passage for supplying an operating oil pressure to a starting clutch or other starting elements of an automatic transmission of a vehicle and an electromagnetic valve capable of closing the oil discharge passage under the demagnetized state and opening it under the excited state is disposed in the oil discharge passage, a method of controlling the creep preventing device is characterized in that when the electromagnetic valve is returned from the excited state to the demagnetized state, the electromagnetic valve is chopped a predetermined number of times. This method can re-connect the starting elements smoothly without incurring any shock.
摘要:
A drive arrangement for motor vehicles, especially for passenger motor vehicles, having an automatically shifting transmission and a mechanism for raising the idling rotational speed of the driving engine during a warm-up phase. The automatically shifting transmission includes a servo-device which, in a first position of a command slide valve, is adapted to be shifted into a position for a first speed range and, in a second position of the command slide valve, is adapted to be shifted into a position for a second speed range. A kickdown solenoid valve acting on the command slide valve is provided which, during actuation of a kick-down switch, passes over into a down-shifting position. A shifting-up relay opening, when energized, is connected in parallel with the kick-down switch whereby a switch is connected in the energizing circiuit of the shifting-up relay which closes the energizing circuit of the shifting-up relay upon actuation of a brake pedal in such a manner that the kick-down solenoid valve passes over into a shifting-up position during the actuation of the brake pedal.
摘要:
When the driver makes a request for switching the shift range to the P range despite that the vehicle has not yet stopped completely, the wheel cylinder pressure is maintained at a brake hold pressure Ph for a while, rather than switching the shift range to the P range immediately. At this time, more specifically, the wheel cylinder pressure is maintained at the brake hold pressure Ph for a brake hold duration Δt within which the vehicle is estimated to stop, and when the brake hold duration Δt has passed, the shift range is switched to the P range. After the lock mechanism is actuated to establish the P range, the wheel cylinder pressure is gradually reduced from the brake hold pressure Ph at a given pressure reducing gradient.