A pressure control valve, in particular for an automatic transmission in a motor vehicle, including a housing and including a control piston situated in the housing, the control piston being actuatable by an armature situated in a magnet chamber of a pole tube, the magnet chamber being hydraulically connected to a compensating chamber provided in the housing, which is delimited, in particular by a lateral surface of a solenoid coil and the housing.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. A controller controls the shift actuator utilizing an actuating pulse and an opposing pulse.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. A controller controls the shift actuator utilizing an actuating pulse and an opposing pulse.

A continuously variable transmission control system includes a continuously variable transmission (CVT) including a primary variator pulley and a secondary variator pulley each including a set of pulley members defining a variable-width gap, and a flexible member positioned within the variable-width gap and movable to define a CVT ratio. The transmission control system also includes a primary pulley valve controlling a primary pulley pressure of a fluid to the primary variator pulley, a secondary pulley valve controlling a secondary pulley pressure of the fluid to the secondary variator pulley; and a pulley pressure control system configured to recognize and mitigate pressure oscillations occurring in the primary pulley pressure or in the secondary pulley pressure.

A continuously variable transmission control system includes a continuously variable transmission (CVT) including a primary variator pulley and a secondary variator pulley each including a set of pulley members defining a variable-width gap, and a flexible member positioned within the variable-width gap and movable to define a CVT ratio. The transmission control system also includes a primary pulley valve controlling a primary pulley pressure of a fluid to the primary variator pulley, a secondary pulley valve controlling a secondary pulley pressure of the fluid to the secondary variator pulley; and a pulley pressure control system configured to recognize and mitigate pressure oscillations occurring in the primary pulley pressure or in the secondary pulley pressure.

A vehicle control apparatus includes a learning control portion configured to execute a learning control operation, and to limit a learning value obtained through the learning control operation, by a guard value, and an update control portion configured to obtain a new guard value from an external device, and to update the guard value to the new guard value. The update control portion limits the learning value by the new guard value, prior to execution of the learning control operation, such that the learning value is rewritten, by the update control portion, to a value within a new guard-value range defined by the new guard value in a case in which the learning value is deviated from the new guard-value range, and such that the learning value is kept unchanged by the update control portion in a case in which the learning value is within the new guard-value range.

A method for determining a conveying capacity of a hydraulic pump includes opening a blockable flow cross-section in order to connect a pressure side of the hydraulic pump to an area of the hydraulic system through the flow cross-section after operating the hydraulic pump driven at a defined rotational speed. The flow cross-section is configured with the hydraulic pump such that an entire conveying volume flow provided by the hydraulic pump is guided through the flow cross-section when the flow cross-section is open. The method further includes comparing a change to an operating state of the transmission resulting from opening of the flow cross-section to a reference change to the operating state and determining the conveying capacity of the hydraulic pump as a function of a deviation between the change to the operating state and the reference change to the operating state.

A transmission calibration tool automatically generates a detailed gearbox model based on a user input transmission topology description. During transmission calibration, the tool accepts inputs from transmission speed and torque sensors and estimates component torques for each gear element and each shift element. Following a shift or other transmission event, the calibration tool plots the component torques as a function of time, permitting the calibration engineer to better understand what is occurring during the event, and thus reducing the time required for calibration. The calibration tool also adapts several transmission component models and outputs the adapted models to provide insight into actual transmission component behavior.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets controls the shift actuator with actuating and opposing pulses, and interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets controls the shift actuator with actuating and opposing pulses, and interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.