摘要:
A power transmission system includes a first transmission provided in a first power transmission path, a second transmission provided in a second power transmission path, a first engagement device, a second engagement device, a third engagement device, a fail-safe valve, and an electronic control unit. The third engagement device selectively connects or interrupts one of the first and second power transmission paths. The electronic control unit is configured to, during traveling in a state where the third engagement device is released, output hydraulic pressure commands for simultaneous engagement of the first engagement device and the second engagement device. The electronic control unit is configured to, when it is determined that both the first engagement device and the second engagement device are engaged, prohibit traveling using the one of the first and second power transmission paths which is selectively connected or interrupted by the third engagement device.
摘要:
A shift by wire control for a multi-speed vehicle transmission is provided. The control includes a shift by wire shift valve in fluid communication with other shift valves and clutch trim valves to provide double blocking features in the neutral range and a reverse range. The shift by wire valve is configured with multiple differential areas to provide failure modes for all forward ranges.
摘要:
A method of controlling an automated transmission with positioning cylinders (6, 8, 20) controlled by shift valves or venting valves (10, 12, 16, 18, 22, 24). At least one cut-off valve (4) is positioned in front of the shift or venting valves and a control device controls the valves while pressure pipes, which follow the cut-off valve (4), are connected with one another following the cut-off valve (4). Due to the fact that the cut-off valve (4), for reasons of design simplicity and cost, is generally designed as a simple 2/2 way valve which only allows pressure increase but not pressure reduction, the method provides control of the shift valves or ventilation or venting valves (16, 18), of a non activated positioning cylinder (8), so that the pressure pipe system is connected with an outflow pipe (14) for a pressure reduction in the pressure pipe system (30, 32, 34).
摘要:
A control for a multi-speed automatic vehicle transmission is provided. Electrical and hydraulic components are provided, including pressure control or “trim” valve systems in fluid communication with shift valves and electrohydraulic actuators to selectively engage and disengage the transmission clutches or other shift mechanisms. Pressure switches are provided for the trim valves and shift valves. The fluid connections between the trim valve systems and the shift valve systems are configured to reduce the total number of valves and fluid passages required and to reduce the size of at least one of the valves. Clutch blocking features are provided. Power off limp home and reduced engine load at stop features are provided in all forward ranges, and control of double transition shifts is also provided.
摘要:
Provided is a range switching device for performing switching among drive, reverse, and neutral ranges of a transmission. The device includes a first switching valve driven by a first actuator and a second switching valve driven by a second actuator. The valves switch an oil channel to transmit the oil pressure from an oil pressure supply source between first state and second states. When the first and second switching valves are in the first and second states respectively, the oil pressure is transmitted to the forward fastening element. When the first and second switching valves are in the second state and first states respectively, the oil pressure is transmitted to the reverse fastening element. When both the valves are in the first or second state, oil pressure transmission to the forward and reverse fastening elements is substantially blocked.
摘要:
A shift by wire control for a multi-speed vehicle transmission is provided. The control includes a shift by wire shift valve in fluid communication with other shift valves and clutch trim valves to provide double blocking features in the neutral range and a reverse range. The shift by wire valve is configured with multiple differential areas to provide failure modes for all forward ranges.
摘要:
A shift by wire control for a multi-speed vehicle transmission is provided. The control includes a shift by wire shift valve in fluid communication with other shift valves and clutch trim valves to provide double blocking features in the neutral range and a reverse range. The shift by wire valve is configured with multiple differential areas to provide failure modes for all forward ranges.
摘要:
In a hybrid power system, when a change-speed stage selected in one of gear-shift mechanisms for first and second drive trains is switched over to another change-speed stage in the other gear-shift mechanism, deceleration in rotation speed of an engine detected by a rotation speed sensor is compared with a preset upper limit. When the deceleration in rotation speed of the engine exceeds the upper limit, the motor-generator in drive connection with an input shaft of the second drive train is activated as an electric motor to cause load torque canceling or offsetting input torque applied to the input shaft of the other gear-shift mechanism from the engine, and engagement of the change-speed stage in the other gear-shift mechanism is released after the occurrence of the load torque.
摘要:
In a control arrangement for an automated gear shift transmission, particularly a dual clutch transmission, which provides for a plurality of functionalities with a relatively small number of slides and control valves, a first gear slide, which is assigned to a first shift device and by means of which an actuation pressure can be applied to the first shift device, has a first and a second supply input for the first and second movement direction of the piston. A supply pressure slide, by means of which a supply pressure can be directed to the gear slide, has first and second supply outputs, which are respectively connected to the first and second supply inputs of the gear slide. The supply pressure slide is designed in such a manner that it can direct a supply pressure optionally to one of the two supply outputs.
摘要:
One of two clutches etc. engaged concurrently with each other to establish a second speed, a third speed, or a fourth speed is determined in advance as an abnormal-time engagement element that is kept engaged when an abnormality occurs in which one different clutch or brake is engaged during concurrent engagement of the two clutches etc. The other of the two clutches etc. is determined in advance as an abnormal-time slipping element that is caused to slip when such an abnormality occurs. During concurrent engagement of the two clutches etc., a hydraulic pressure (target hydraulic pressure) to be supplied to the abnormal-time engagement element is set to be higher than a hydraulic pressure (target hydraulic pressure) to be supplied to the abnormal-time slipping element.