A control apparatus controls a driving force transmission device including: an electric motor; a pressing mechanism to convert the rotational force of the motor into an axial pressing force; friction clutches including friction members configured to come into frictional engagement with each other by the pressing force provided by the pressing mechanism. The driving force transmission device is configured to transmit a driving force between a pair of rotary members by the friction clutches. The apparatus includes: a target current calculating circuit to calculate a target current to be supplied to the motor; and a correction circuit to correct a voltage to be applied to the motor so as to reduce a difference between the target current and an actual current supplied to the motor. The correction circuit increases or reduces, in accordance with the actual current, the amount of correction of the voltage to be applied to the motor.

A system includes an engine, a transmission driven by the engine, and a controller. The controller is configured to receive a speed input, receive feedback indicative of a load of the engine at a current engine speed, compare the load to a predetermined load threshold at the current engine speed, determine an expected engine speed based at least on the current engine speed, a current gear ratio, and an expected gear ratio, determine an estimated engine power at the expected engine speed and a current engine power at the current engine speed, and command a gear downshift when the load is greater than or equal to the predetermined load threshold and when the estimated engine power is greater than the current engine power.

The disclosure discloses a control unit for the electrohydraulic actuation of motor vehicle assemblies, having a main housing and at least one valve unit which can be inserted into the main housing. The valve unit has a metal valve housing for receiving an electrically actuable valve, a plug housing which is fastened to the valve housing and is formed from a plastics material, and a connection contact which is received in the plug housing and can be electrically connected to the valve. A clamping contact for electrically connecting the connection contact of the valve unit to an actuating electronics system is connected to the main housing. The plug housing forms a dielectric resistance between the clamping contact and the valve housing. An installation space-saving and safe control unit is rendered possible owing to the fact that the plug housing forms a dielectric resistance between the clamping contact and the valve housing.

A method for maintaining an engine speed of an engine of a work vehicle includes sending a requested parameter indicative of the engine speed to an engine controller of the work vehicle. The method also includes receiving a measured parameter indicative of the engine speed. The method further includes determining whether the requested parameter is different from the measured parameter. The method also includes setting a controller-requested parameter indicative of the engine speed based at least in part on the requested parameter and the measured parameter. The method further includes sending the controller-requested parameter to the engine controller. The method accounts for speed and torque saturation in order to avoid windup in the controller.

The present invention relates to a hydraulic-oil control device that performs hydraulic-oil supply control in a dual clutch device having a first clutch and a second clutch. The hydraulic-oil control device includes a first linear solenoid valve that adjusts hydraulic oil having a line pressure for a first hydraulic chamber and supplies the hydraulic oil thereto, a second linear solenoid valve that adjusts hydraulic oil having a line pressure for a second hydraulic chamber and supplies the hydraulic oil thereto, a shuttle valve that outputs the hydraulic oil having a higher pressure between the pressure of the hydraulic oil in the first hydraulic chamber and the pressure of the hydraulic oil in the second hydraulic chamber, and a switch valve that adjusts the amount of hydraulic oil supplied to a first space and a second space, according to the pressure of the hydraulic oil output from the shuttle valve.

An AWD-vehicle control device includes a transfer clutch that adjusts a driving force, a detector that detects a steering angle of a steering wheel, a detector that detects an accelerator pedal opening, a detector that detects a vehicle speed, a detector that detects an engine revolution speed, a detector that detects a turbine revolution speed of a torque converter, and a transfer clutch controller that adjusts hydraulic pressure supplied to the transfer clutch and controls a coupling force of the transfer clutch. If a predetermined period has passed from the accelerator pedal opening becoming less than a predetermined opening, the vehicle speed is within a predetermined range, a deviation between the engine and turbine revolution speeds is less than a predetermined speed, and the steering angle is equal to a first predetermined angle or greater, the transfer clutch controller controls the hydraulic pressure to reduce the coupling force.

A drive power distribution device includes a hydraulic pressure sealing-type hydraulic pressure control device for making an operation noise of an on-off valve such as a solenoid valve less recognizable to occupants of a vehicle. By closing the on-off valve and driving the oil pump, a hydraulic pressure detected using a hydraulic pressure detection means reaches a target hydraulic pressure, and fastening power of a hydraulic clutch is maintained at an oil pressure of hydraulic fluid sealed in an oil passage until the on-off valve is opened. The drive power distribution device closes the solenoid valve when the hydraulic pressure is detected to be equal to or less than a predetermined threshold hydraulic pressure and equal to or less than a predetermined threshold vehicle speed. This can prevent synchronization between an accelerator operation by a driver and a closing operation of the solenoid valve.

A valve device (2), of a pneumatically actuatable friction clutch engageable by spring force, includes at least one inlet valve (16, 18) connected on the input side to a pressurized supply line and on the output side to an actuating cylinder of the friction clutch. A pressure-sustaining valve (20, 28) is upstream or downstream of the inlet valve and is designed as a check valve closing in the backflow direction. The pressure-sustaining valve is a springless check valve and includes a housing ring (22, 30) having a retaining basket (36), a closing element (24, 32), and a valve seat (26, 34). The closing element, in the depressurized state and with a positive pressure gradient is held in the retaining basket (36) of the housing ring (22, 30) and, with a negative pressure gradient is pressed out of the retaining basket (36) and against the valve seat (26, 34).

A system and method for determining a remaining useful life of a portion of a wet clutch system is provided. The system comprises a first clutch assembly, a proportional valve, a sensor, and a controller. The proportional valve regulates a pressure applied to the first clutch assembly. The sensor measures a response of the first clutch assembly during one of engaging and disengaging a first portion of the first clutch assembly with a second portion of the first clutch assembly. The controller controls the proportional valve, calculates a mean coefficient of friction of the first clutch assembly based on the sensed response of the first clutch assembly, and determines a remaining useful life of a portion of the wet clutch system based on the mean coefficient of friction of the first clutch assembly.

According to one embodiment, a current detection circuit (12) includes: a detection resistor (Rs) provided between a solenoid valve (106) and a solenoid driver (11); an amplification unit (121) configured to amplify a detected voltage of the detection resistor (Rs); an AD converter (122) that is driven by a reference voltage (Vref) generated based on a reference current (Iref) and configured to convert an output voltage from the amplification unit (121) into a digital value and output the digital value as a detected current value (D1); and a correction unit configured to perform a correction on the detected current value (D1). The correction unit includes: a temperature sensor (123); a storage unit (125) configured to store information about temperature characteristics of the detected current value (D1) generated due to temperature characteristics of a reference current in each of two or more different temperature regions; and an operation unit configured to apply, to the detected current value (D1), a first correction coefficient calculated based on a detection result of the temperature sensor (123) and information about temperature characteristics of the detected current value (D1) stored in the storage unit (125).