4394results about "Clutches" patented technology

A hydraulic circuit may include a proportional control solenoid valve controlling hydraulic pressure such that an operating hydraulic pressure required by the friction member is supplied to the friction member; a supply hydraulic path connecting the proportional control solenoid valve with the friction member, and adapted to supply hydraulic pressure controlled by the proportional control solenoid valve to the friction member; and a switch valve disposed in the supply hydraulic path so as to selectively open / close the supply hydraulic path.

A method and an apparatus are provided to control operation of an electro-mechanical transmission device selectively operative in one of a plurality of fixed gear modes and two continuously variable modes. The method comprises controlling the flow control devices of the electro-hydraulic control circuit, and monitoring a plurality of pressure monitoring devices in the electro-hydraulic control circuit. A fault is identified in the electro-hydraulic control circuit when a signal output of one of the pressure monitoring devices does not correspond to an expected signal output for the pressure monitoring device after an elapsed time period.

A method and apparatus to control an electrically variable transmission, by dynamically controlling system main hydraulic clutch pressures, based upon required clutch capacity, as determined by output load of the transmission. Included is a method to regulate hydraulic clutch pressure in an electrically variable transmission equipped with at least one clutch. This comprises monitoring magnitude of slippage of the clutches and controlling hydraulic boost pressure based upon the magnitude of clutch slippage. Controlling hydraulic boost pressure based upon the magnitude of clutch slippage comprises monitoring operator inputs, determining a requested operator torque command, and determining a required main boost pressure. The main boost pressure is based upon the requested operator torque command, the monitored operator inputs, parameters of the EVT and clutches. Commanded main boost pressure is then determined based upon the determined required main boost pressure.

A method of controlling the clutches of a dual clutch transmission during a two-gear positive downshift, wherein the first clutch drives an initial gear and the final gear and the second clutch drives an intermediate gear. The torque transfer across each clutch is controlled so that the torque output of the transmission will be linearly changed over from the first clutch to the second clutch to cause the engine to track a target engine speed profile. The method changes over the gears driven by the first clutch from the initial gear to the final gear as the engine continues to tracks the target speed. The torque transfer across each clutch is controlled so that the torque output will be linearly changed back from the second clutch to the first clutch in an inversely proportional rate to continue to cause the engine to track the target engine speed profile.

A hybrid vehicle drive control system has a first clutch interposed between an engine and a motor / generator, a transmission including several gear position clutches arranged between the motor / generator and a drive wheel, and a controller. The controller selectively starts the engine using torque from the first clutch during a mode drive change from an electric drive mode to a hybrid drive mode. When an engine start command occurs during the drive mode change, the controller selects the engaged gear position clutch that has the maximum torque transfer capacity from the engaged clutches constituting a vehicle running gear occurring during an engine starting process as a second clutch to be controlled. Then the controller executes a slip control of the second clutch when the first clutch is being connected to start the engine during the mode change from the electric drive mode to the hybrid drive mode.

A hybrid vehicle control apparatus includes an engine, a motor, first and second engaging elements, an input rotational speed and a controller. The first engaging element is arranged between the engine and the motor to selectively connect and disconnect the engine and the motor. The second engaging element is arranged between the motor and a drive wheel to selectively connect and disconnect the motor and the drive wheel. The input rotational speed detecting section is configured to detect an input rotational speed of the second engaging element corresponding to a rotational speed of the motor. The controller is configured to determine whether the second engaging element is seized based on the input rotational speed when a disengagement command or a slip engagement command has been issued to the second engaging element and a drive force of at least one of the engine and the motor has been changed.

An engine staring control apparatus of a hybrid drive system is arranged to increase the torque transmission capacity such that a cranking torque of an engine is compensated when the engine is started; to stop the increase of the torque transmission capacity when a revolution speed of an engine-side friction element of an engine clutch reaches a revolution speed at which the engine can start by itself; to hold a torque transmission capacity of the engine clutch after the stopping of the increase of the torque transmission capacity; and to stop the holding of the torque transmission capacity and to again increase the torque transmission capacity when the revolution speed of the engine-side friction element reaches the revolution speed of a transmission-side friction element.

The invention belongs to automobile transmissions, in particular to a hydraulic control system for a wet-type double-clutch automatic transmission. The hydraulic control system consists of two separate subsystems, wherein one subsystem is a clutch and gearshift mechanism hydraulic control subsystem which is mainly used for operating an odd number gear clutch and an even number gear clutch to separate and combine according to a control signal transmitted by an electronic control unit as well as operating a gear-shift mechanism control oil cylinder to finish switching of each gear synchronizer; and the other subsystem is a clutch cooling and lubricating subsystem. By adopting a more scientific and reasonable hydraulic control system, the efficiency of the hydraulic control system for the wet-type double-clutch automatic transmission is improved, the fuel consumption is reduced, the effects of saving energy and reducing emission are achieved, and the reliability of the system work and the compactness of the structure are enhanced.

The present invention makes it possible to start the engine when switching from the electric driving (EV) mode to the hybrid (HEV) mode without feeling of torque loss and with low impact. At t1 when the EV→HEV mode switching request increases with the acceleration, the control is started using the mode 2301b, and the transmission torque capacity tTc1 of the first clutch for HEV is increased for driving force control. Before the second clutch for EV&HEV starts to slip, The PTO shaft of the engine is started to rotate by the drag of the first clutch. In the mode 2301b, the second clutch transmission torque capacity tTc2 is maintained at the maximum driving force evTmax in the EV mode. Switch to mode 2303 at t2 when the second clutch starts to slip, and determine tTc2 so that the second clutch slips and start the engine caused by the drag of the first clutch, and tTc1 is determined to maintain the increase in driving force and the stability of the second clutch slide.

A method for controlling the drive unit of a vehicle in which an extended overrun mode having reduced fuel consumption and reduced pollutant emission is possible. A free-wheel mode in which the vehicle operates with the clutch disengaged is set as a function of a driving situation or an operating state of the drive unit. An output variable of the drive unit, such as torque or vehicle speed, is set to a constant value during the transition between an engaged-clutch travel mode and a free-wheel mode.

A method of controlling the timing of the shift events of a dual clutch transmission that includes the steps of sensing the current output speed of the transmission, determining the time required to complete each possible shift event within the transmission, and determining an output speed modification value for each possible shift event. The method also includes the steps of determining a modified shift point output speed for each possible shift event by summing the determined output speed modification value with a predetermined shift pattern output speed, and commanding the shift when the current output speed reaches the determined modified shift point output speed.

A hybrid vehicle drive control system is configured to perform engine startup when switching from an electric drive mode to a hybrid drive mode, without creating a sense of output torque loss. In particular, a controller selectively controls a first clutch disposed between the engine and the motor / generator and a second clutch disposed between the motor / generator and a drive wheel to switch between an electric drive mode in which the first clutch is released and the second clutch is engaged, and a hybrid drive mode in which both the first and second clutches are engaged. The controller sets the second torque transfer capacity to a value that is more than zero and less than the target motor / generator torque of the motor / generator when switching from the electric drive mode to the hybrid drive mode and when starting the engine.