Abstract: An electro-hydraulic control for a continuously variable transmission includes a first regulator valve which is controlled to provide a high pressure output to control the ratio within the continuously variable transmission and a second regulator valve which is controlled to provide an engagement pressure for torque transmitting mechanisms within the transmission. The control incorporates multiplexing of the valve components, creates prioritization of fluid flow, detection of priority mode of operation, over-pressurization protection valves, and ensures a minimum of fluid flow to the torque transmitting mechanisms and the oil cooler.

Abstract: An electro-hydraulic control mechanism provides controlled engagement pressure for both a torque converter clutch and a shifting torque transmitting mechanism. The control mechanism include a TCC regulator valve that establishes the engagement pressure for the torque converter clutch and a TTM regulator valve that controls the engagement pressure for the torque transmitting mechanisms. An electronically-controlled variable bleed solenoid controls the output pressure level of both of the regulator valves. A control valve is employed to multiplex the output of the regulator valves and to ensure that the torque transmitting mechanism remains engaged during the engagement of the torque converter clutch. The control valve also ensure that the output pressure of the TTM regulator valve is communicated with a manual control valve in the event of an unexpected discontinuance of electrical power.

Abstract: An electro-hydraulic control for a continuously variable transmission includes a first regulator valve which is controlled to provide a high pressure output to control the ratio within the continuously variable transmission and a second regulator valve which is controlled to provide an engagement pressure for torque transmitting mechanisms within the transmission. The control incorporates multiplexing of the valve components, creates prioritization of fluid flow, detection of priority mode of operation, over-pressurization protection valves, and ensures a minimum of fluid flow to the torque transmitting mechanisms and the oil cooler.

Abstract: An electro-hydraulic control mechanism provides controlled engagement pressure for both a torque converter clutch and a shifting torque transmitting mechanism. The control mechanism include a TCC regulator valve that establishes the engagement pressure for the torque converter clutch and a TTM regulator valve that controls the engagement pressure for the torque transmitting mechanisms. An electronically-controlled variable bleed solenoid controls the output pressure level of both of the regulator valves. A control valve is employed to multiplex the output of the regulator valves and to ensure that the torque transmitting mechanism remains engaged during the engagement of the torque converter clutch. The control valve also ensure that the output pressure of the TTM regulator valve is communicated with a manual control valve in the event of an unexpected discontinuance of electrical power.

Abstract: A clutch assembly and charging system combination for use with an automatic transmission includes a clutch assembly having a clutch that is movable between a clutch engaged position and a clutch disengaged position. The clutch assembly further includes a clutch piston that is engageable with the clutch for urging the clutch toward the clutch engaged position, a clutch piston chamber in fluid communication with one side of the clutch piston, and a compensator chamber in fluid communication with an opposite side of the clutch piston. The combination further includes a charging system having a fluid circuit that is in fluid communication with the clutch piston chamber and the compensator chamber. The fluid circuit is configured to receive exhaust oil from the transmission, and to charge the clutch piston chamber and the compensator chamber using the exhaust oil.

Abstract: An engagement pressure control apparatus for a torque-transmitting mechanism in a transmission control apparatus includes a regulator valve and a boost valve. The regulator valve provides a controlled pressure rise to a torque-transmitting mechanism within the transmission during a shifting event, and the boost valve is effective to increase the fluid pressure from the regulator valve to the torque-transmitting mechanism when the shift event has been completed, thereby providing a high pressure at the torque-transmitting mechanism to prevent slipping.

Abstract: A powertrain has an electro-hydraulic control mechanism that provides for the establishment of six forward speeds, a neutral condition and a reverse speed. The control system also permits operation in the fifth forward range if electrical power is discontinued when the transmission is operating in the third range or higher, and permits operation in the third range if the transmission is operating in the second range or lower when an electrical power discontinuance occurs. If an electric disconnect occurs, the reverse drive is available, neutral is available, and third forward drive is available from the reverse and neutral conditions. The drive-home functions described are provided through the use of a multiplex valve, default valve and a pair of solenoid valves. The multiplex valve and default valve also permit the controlling of two mutually exclusive torque transmitting devices through the use of a single trim valve.

Abstract: A clutch assembly and charging system combination for use with an automatic transmission includes a clutch assembly having a clutch that is movable between a clutch engaged position and a clutch disengaged position. The clutch assembly further includes a clutch piston that is engageable with the clutch for urging the clutch toward the clutch engaged position, a clutch piston chamber in fluid communication with one side of the clutch piston, and a compensator chamber in fluid communication with an opposite side of the clutch piston. The combination further includes a charging system having a fluid circuit that is in fluid communication with the clutch piston chamber and the compensator chamber. The fluid circuit is configured to receive exhaust oil from the transmission, and to charge the clutch piston chamber and the compensator chamber using the exhaust oil.

Abstract: A powertrain has an electro-hydraulic control mechanism that provides for the establishment of six forward speeds, a neutral condition and a reverse speed. The control system also permits operation in the fifth forward range if electrical power is discontinued when the transmission is operating in the third range or higher, and permits operation in the third range if the transmission is operating in the second range or lower when an electrical power discontinuance occurs. If an electric disconnect occurs, the reverse drive is available, neutral is available, and third forward drive is available from the reverse and neutral conditions. The drive-home functions described are provided through the use of a multiplex valve, default valve and a pair of solenoid valves. The multiplex valve and default valve also permit the controlling of two mutually exclusive torque transmitting devices through the use of a single trim valve.

Abstract: A hydraulic circuit for an automatic transmission operable to reduce time delay in shifting includes a source supplying pressurized fluid through a feed orifice and a charging circuit including an accumulator. The accumulator is downstream of the feed orifice, and operates to reserve pressurized fluid supplied by the source. The hydraulic circuit also includes a clutch circuit, downstream of the charging circuit, which has a clutch hydraulically actuated and operable to generate torque to shift the automatic transmission. A valve is interposed between the charging circuit and the clutch circuit to open a flow path therebetween to start a shift cycle of the clutch. When the valve is actuated, the pressurized fluid is released from the accumulator and flows to the clutch circuit to minimize delay in the shift.

Abstract: A hydraulic circuit for an automatic transmission operable to reduce time delay in shifting includes a source supplying pressurized fluid through a feed orifice and a charging circuit including an accumulator. The accumulator is downstream of the feed orifice, and operates to reserve pressurized fluid supplied by the source. The hydraulic circuit also includes a clutch circuit, downstream of the charging circuit, which has a clutch hydraulically actuated and operable to generate torque to shift the automatic transmission. A valve is interposed between the charging circuit and the clutch circuit to open a flow path therebetween to start a shift cycle of the clutch. When the valve is actuated, the pressurized fluid is released from the accumulator and flows to the clutch circuit to minimize delay in the shift.

Abstract: A torque transmitting rotating body in the vehicle has a desired rotational direction during vehicle travel in response to an operator demand. Rotation of the body is determined by a speed sensor which provides a signal to a control system. The control system determines the direction of rotation from consecutive speed signals and a known input torque. The control then issues the appropriate commands to ensure the direction of rotation of the body is in accordance with the operator demand.