Abstract: A powertrain includes a first pump and a second pump. A conduit defines a passageway for providing hydraulic pressure from the first pump or the second pump to a transmission. A valve assembly is configured to selectively supply hydraulic pressure to the passageway solely from the first pump, solely from the second pump, and from both the first and second pumps. The valve assembly thus enables the first and second pump to augment one another, thereby enabling the size of at least one of the pumps to be smaller than would otherwise be possible without the valve assembly.

Abstract: A torque-transmitting regulating system employs a valve mechanism, which distributes fluid pressure from a pressure source to a torque-transmitting mechanism by control for the engagement and disengagement thereof. The valve mechanism has associated therewith a pressure sensor mechanism, which distributes a control signal to the electronic control module (ECM) to inform the ECM of the condition of operation of the torque-transmitting mechanism. A valve mechanism supplies a first pressure signal during disengagement of the torque-transmitting mechanism, a second pressure signal during the filling period of the torque-transmitting mechanism, and a third signal during the fully engaged condition of the torque-transmitting mechanism.

Abstract: A hydraulic control system for a continuously variable transmission includes a source of fluid pressure provided by a pump and regulator valve. The fluid pressure of the pump is directed to a primary regulator valve, which issues a control pressure signal for a variable sheave control and a ratio enable valve, which directs the pressurized primary regulator valve to the variable pulley. The ratio enable valve is operable upon discontinuance of the primary regulator valve issuing a pressure signal and/or in response to a discontinuance of electronic control signal to establish a control pressure at the variable ratio pulley through a feed and bleed orifice system.

Abstract: A regulator valve for controlling the pressure of fluid engaging a torque-transmitting mechanism in a transmission includes a valve body forming a valve bore of a plurality of passages. A spool valve slides within the valve body. A check valve selectively opens and closes one of the passages. A spring is disposed in the valve bore and biases the spool valve in one direction. The spool valve, check valve, spring, valve bore and passages are configured to control the pressure fluid provided to the torque-transmitting mechanism and a linearly increasing pressure until a first predetermined pressure is achieved and then at a second constant predetermined pressure greater than the first predetermined pressure, thus combining gradual clutch engagement during shifting with valve boost necessary for static capacity requirements. A method of controlling engagement of the torque-transmitting mechanism is also provided.

Abstract: A method for adaptively learning clutch volumes and fill level to compensate for build tolerances and clutch wear includes increasing a fill level of a clutch during an oncoming fill phase of a clutch to clutch transmission. A state of a regulator valve of the clutch to clutch transmission is monitored during the oncoming fill phase. Fill level of the clutch is adjusted before a next shift based on whether the regulator valve switches from a regulating state to a full feed state before elapse of a valid shift time.