A clutch current control circuit may include as a circuit for controlling a current of a clutch connected to a compressor, a strain gauge, wherein a resistance value of the strain gauge is varied according to the movement amount of an Electric Control Valve (ECV) shaft; a switching element of performing a switching operation by comparing a gate-source voltage determined according to a change in the resistance value of the strain gauge and the threshold voltage, and allowing a flow of a first clutch current to generate by a first switching operation state; and a resistor connected in parallel with the switching element, and allowing a flow of a second clutch current to generate by a second switching operation state of the switching element.

Methods and systems for a differential assembly are provided herein. In one example, a method is provided that includes operating a clutch motor coupled to a differential locking clutch to place the differential locking clutch in a locked configuration. The method further includes, after the differential locking clutch is placed in the locked configuration, reducing electric power delivered to the clutch motor at a first rate and increasing the electric power delivered to the clutch motor when it is determined that clutch disengagement is occurring based on outputs from a motor position sensor or outputs from shaft speed sensors coupled to a pair of shafts coupled to the differential locking clutch.

The present invention is a hydraulic pressure control device for an automatic transmission that performs a gear shift by switching between engagement and disengagement of a plurality of friction engagement elements and includes solenoid valves, provided corresponding to the friction engagement elements, respectively, that switches between engagement and disengagement of the friction engagement elements by switching between supply and non-supply of hydraulic pressures to the friction engagement elements, and a control device that switches between supply and non-supply of the hydraulic pressures to the friction engagement elements by supplying a predetermined control current to the solenoid valves, in which the control device supplies a fixation preventing current lower than the control current to at least one of the solenoid valves corresponding to the friction engagement elements in a disengagement state of the plurality of friction engagement elements.

A torque limiter device includes an input shaft having a first contact surface and an output shaft having a second contact surface. The input and output shafts are operable in an engaged position wherein the contact surfaces are brought into mechanical engagement, and a disengaged position wherein the contact surfaces are separated. A biasing mechanism provides a bias force that mechanically biases the input and output shafts in one of the positions and sets a threshold torque. An electromagnet is arranged to selectively provide an electromagnetic force that opposes the bias force when an activation current is supplied. A rotation sensor arrangement measures a respective rotation of the input shaft and of the output shaft. A controller determines a difference in rotations of the shafts and selectively supply the activation current to the electromagnet so as to disengage the input and output shafts when the rotation difference exceeds a threshold.

A driving force transmission control device includes a driving force transmission device configured to press a friction clutch by an actuator and a controller configured to control the driving force transmission device. The controller calculates a torque command value indicating a driving force to be transmitted from a rotating member on an input side to a rotating member on an output side based on information of a vehicle. The controller sets an electric current command value according to a magnitude and an amount of time change of the torque command value. The electric current command value is a target value of an electric current. The controller performs electric current feedback control such that an electric current corresponding to the calculated electric current command value is supplied to the actuator.

A clutch control method for a hybrid vehicle with a DCT of the present invention is provided. The method includes checking whether a current shift range is a D-range and determining a gradient of a current driving road and driver's vehicle stop requirement. In response to determining that the current shift range is the D-range, the gradient of the road is not a gradient that requires uphill driving, and there is driver's vehicle stop requirement, a controller reduces an operation current supplied to a clutch actuator of a clutch for transmitting power to a first gear to a regulation current. The regulation current is set based on an operation of the vehicle by the driver when the vehicle is restarted after the current reduction.

A method for determining a kiss point is disclosed. A drive unit having one or more motors with a motor output shaft is provided. One or more actuation profiles are ran and an amount of motor current and motor shaft position data is measured. The data measured is filtered and one or more motor current vs. motor shaft position plots having one or more curves with a high force and high current region are generated. A derivative is calculated over the curves and a slope of the high force and high current region is determined. A relative slope threshold is determined by multiplying the slopes by a predetermined percentage. One or more lines having a slope substantially equal to the relative slope threshold are plotted. The kiss point is determined based on the position of the motor shaft where the derivative of the curves equals the slope of the lines plotted.

The clutch control device comprises: a pump that feeds oil to a hydraulic clutch; a control part that controls the pump; an input-side oil channel through which oil suctioned into the pump from an oil tank passes; an output-side oil channel connecting the pump and the hydraulic clutch; a pressure sensor; a connecting oil channel connected to the input-side oil channel and the output-side oil channel; and a solenoid valve that interrupts or allows the flow of oil in the connecting oil channel. The opening degree of the valve can be adjusted. When a drive shaft and a driven shaft are connected by the hydraulic clutch, the control part adjusts the opening degree of the valve on the basis of the pressure of oil in the output-side oil channel and the number of rotations made by the driven shaft while monotonically increasing the number of rotations of the drive part.

A driving force transmission device includes an input rotation member, an output rotation member, a multiple-disc clutch, a pressing mechanism, and a control device including a current supply circuit. The control device is configured to compute a torque command value, to compute a current command value, to correct the current command value, and to control the current supply circuit such that an electric current depending on the current command value is supplied to the pressing mechanism. The control device is configure to correct the current command value by a correction amount in a constant-torque state after the torque command value changes, the constant-torque state being a state where a change rate of the torque command value is in a predetermined range, the correction amount depending on a duration of the constant-torque state.

A driving force transmission device includes an input rotation member and output rotation member, a multiple-disc clutch, a pressing mechanism, and a control device that includes a current supply circuit. The control device is configured to compute a torque command value based on a state of a vehicle, the torque command value being a driving force that needs to be transmitted by the multiple-disc clutch, to compute a current command value, to correct the current command value, and to control the current supply circuit such that an electric current depending on the current command value is supplied to the pressing mechanism. The control device is configured to perform the correction so as to increase or decrease the current command value by a correction amount depending on a change rate of the torque command value.