Abstract: A hydraulic control circuit includes a first pressure regulating valve for regulating a pump discharge pressure, a second pressure regulating valve for adjusting a pilot pressure to a torque converter pressure, and a first oil passage that connects an output port of the first pressure regulating valve and a torque-converter input-side oil passage, the second pressure regulating valve having an input port connected to the first oil passage through a second oil passage, a drive port connected to the first oil passage through a third oil passage, a spool axially displaced according to a drive pressure inputted into the drive port for regulating the torque converter pressure, and an output port. A throttle is provided between the connection section of the first and third oil passages and the connection section of the first and second oil passages, for adjusting the torque converter pressure to an appropriate pressure.

Abstract: A hydraulic control circuit includes a first pressure regulating valve for regulating a pump discharge pressure, a second pressure regulating valve for adjusting a pilot pressure to a torque converter pressure, and a first oil passage that connects an output port of the first pressure regulating valve and a torque-converter input-side oil passage, the second pressure regulating valve having an input port connected to the first oil passage through a second oil passage, a drive port connected to the first oil passage through a third oil passage, a spool axially displaced according to a drive pressure inputted into the drive port for regulating the torque converter pressure, and an output port. A throttle is provided between the connection section of the first and third oil passages and the connection section of the first and second oil passages, for adjusting the torque converter pressure to an appropriate pressure.