Systems and methods for improving operation of a driveline disconnect clutch for a hybrid vehicle shifting are presented. In one example, pressure of a working fluid supplied to the driveline disconnect clutch is adjusted in response to a rate of change in accelerator pedal position. Further, pressure of the working fluid may be decreased responsive to selected operating conditions.

An electronic control unit performs lockup clutch engagement control in the sequence of fast fill control, constant-pressure standby control and command pressure raising control, and starts the lockup clutch engagement control from that one of the fast fill control and the command pressure raising control which is later in sequence than the other, as a command pressure for a control oil pressure at a transition time point for making a transition to the lockup clutch engagement control rises, in making the transition to the lockup clutch engagement control during the lockup clutch release control. Therefore, when the command pressure for the control oil pressure is equal to or higher than a predetermined value that is needed to carry out packing for narrowing a pack clearance of a lockup clutch, the lockup clutch engagement control is started from the command pressure raising control.

A method ascertains a characteristic variable of a clutch installed into the powertrain of a vehicle for transmitting torque between a clutch input and a clutch output. A first electric motor is connected to the clutch input to introduce a first drive torque into the clutch. The torque is ascertained when the vehicle is at a standstill in that the clutch is first opened; the first electric motor is regulated at a first rotational speed; the clutch output is regulated at a second rotational speed; a counter torque which counteracts the transmission torque is applied to the clutch output; the clutch is then closed in order to assume a slipping state in which a specific differential rotational speed between the clutch input and the clutch output is present; the first drive torque is then ascertained; and the transmission torque is determined on the basis of the first drive torque.

An electronic automatically decoupling hub assembly is disclosed herein. The decoupling hub assembly has an axle and a hub shell rotationally positioned about the axle. A controller provides automatic activation/deactivation signals to an inductor. The decoupling hub assembly has a bearing rotationally positioned about the axle and a cassette body assembly, having a plurality of teeth, rotationally positioned about the bearing. One or more pawls are provided to engage with at least some of the teeth of the cassette body assembly and a seal is used to contain the pawls within the decoupling hub assembly. A cassette body assembly is coupled with the ratchet ring and an end cap is used to prevent a contaminant from entering into the decoupling hub assembly.

A method ascertains a characteristic variable of a clutch installed into the powertrain of a vehicle for transmitting torque between a clutch input and a clutch output. A first electric motor is connected to the clutch input to introduce a first drive torque into the clutch. The torque is ascertained when the vehicle is at a standstill in that the clutch is first opened; the first electric motor is regulated at a first rotational speed; the clutch output is regulated at a second rotational speed; a counter torque which counteracts the transmission torque is applied to the clutch output; the clutch is then closed in order to assume a slipping state in which a specific differential rotational speed between the clutch input and the clutch output is present; the first drive torque is then ascertained; and the transmission torque is determined on the basis of the first drive torque.

This clutch control device is provided with: a first valve; a second valve; a valve control unit configured to control the operation of each of the first valve and the second valve; an operation determination unit configured to perform an operation determination for the clutch device; and an initial operation completion determination unit which determines whether an initial operation of the clutch device has been completed. The valve control unit, if it is determined by the operation determination unit that an on-off switching process is required, subjects both the first valve and the second valve to opening-control. If it is determined by the initial operation completion determination unit that the initial operation has been completed, the valve control unit subjects the second valve to closing-control.

A vehicle control device applicable to a vehicle including an engine includes an electric motor coupled to the engine, a hydraulic clutch, a solenoid control valve, a first travel control unit, a second travel control unit, and a fail-safe control unit. The hydraulic clutch is engaged when hydraulic oil is supplied and disengaged when the hydraulic oil is discharged. The solenoid control valve includes a solenoid. The solenoid control valve supplies the hydraulic oil to the hydraulic clutch when the solenoid is in a non-energized state, and discharges the hydraulic oil when the solenoid is in the energized state. The first travel control unit executes an engine traveling mode, and the second travel control unit executes an inertial traveling mode. The fail-safe control unit drives the electric motor when the solenoid is switched from the energized state to the non-energized state while the inertial traveling mode is executed.

A control device includes: an engagement mechanism having a first engagement element and a second engagement element; and an actuator that generates a thrust that brings the first engagement element and the second engagement element close to each other when the engagement mechanism is engaged. The control device performs engagement with the thrust of the actuator when a differential rotation speed of the engagement mechanism is less than a predetermined value. In the control device, a parameter indicating an operating state of the actuator is detected, a target differential rotation speed is calculated in accordance with a value of the detected parameter, and the differential rotation speed is controlled to the calculated target differential rotation speed.

An engine system provided to a vehicle having an accelerator pedal is provided. When an engine operation range is determined to shift to a first range (where an electromagnetic clutch is disengaged) from a second range (where the clutch is engaged) after an opening of the accelerator pedal increases at a rate below a given reference rate, the clutch is switched from ON to OFF after a given basic stand-by period passes from the shift. When the engine operation range is determined to shift from the second range to the first range after the accelerator pedal opening increases at the given reference rate or above, the clutch is switched from ON to OFF after a given acceleration stand-by period (longer than the basic stand-by period by a given added period) passes from the shift.

Methods and system are described for changing a driveline gear range from a higher gear range to a lower gear range. The driveline may include two electric machines and four clutches in a four wheel drive configuration. The methods and systems permit a driveline to change from a higher gear range to a lower gear range without stopping a vehicle.