Aisin Seiki Kabushiki Kaisha

Shiro Sonoda

Kazuaki Watanabe

Teruo Akashi

Isamu Minemoto

Yoshinobu Iwase

Koichi Yamashito

A fluid pressure control device having a timing valve with a spool which is adopted in an automatic transmission so as to operate in such a manner that a fluid pressure from a friction portion at a low speed side to the timing valve is drained rapidly therefrom due to axial movement of the spool according to a signal indicating an engine output upon a power-off up-shifting is comprised of a first pressure source from which a pressure indicating the engine output is set to be applied to one end of the spool, a second pressure source from which a pressure is set to be applied to the other end of the spool so as to be balanced with the pressure from the first pressure source across the spool other than the power-off up-shifting, and a device for increasing the pressure applied to one end of the spool from the first pressure source on the basis of a condition relating to an accelerator upon power-off up-shifting.

Fluid pressure control device for automatic transmission

A hydraulic control apparatus for an automatic transmission having a mechanical parking mechanism includes a manual valve disposed in the hydraulic control apparatus and having a parking (P) position, reverse (R) position, neutral (N) position and at least one forward speed position. The manual valve is provided with a drain port for releasing, in the parking position, the hydraulic pressure of a hydraulic circuit which establishes the reverse range, and the drain port is provided with an orifice which limits the discharge rate of hydraulic pressure.

Hydraulic control apparatus for automatic transmissions

A governor valve for an automatic transmission comprising a valve body and a body support secured together and for rotation with an output shaft of the transmission. A line pressure passage connected to pressured fluid in the transmission and a governor pressure passage for operating the governor are formed in the body support, and passage means in the governor body connects the line pressure passage to the governor pressure passage. A normally closed valve is disposed in the passage means and normally blocks communication between the line pressure passage and the governor pressure passage, and the valve is operable to open in response to centrifugal force imparted thereto during rotation of the shaft to communicate the line pressure passage with the governor pressure passage and to actuate the governor. The passage means includes a bore in the governor valve body which is inclined relative to the axis of rotation of the shaft, and a strainer is disposed in the bore to prevent foreign matter from entering the valve.

Growing community of inventors

Aichi, Japan

Shiro Sonoda