Honda Giken Kogyo Kabushiki Kaisha

Honda Giken Kabushiki Kaisha

Kenichi Haraguchi

Hideki Wakamatsu

Takafumi Sakai

Masaaki Takamatsu

A control apparatus for a hydraulically operated vehicular transmission having a plurality of hydraulic engaging elements has an accumulator which is connected in parallel with a hydraulic engaging element for a low-speed transmission train and a back pressure generating source which generates a hydraulic oil pressure to be supplied to a back pressure chamber of the accumulator. The control apparatus includes a changeover valve which can be changed over between a first position in which the back pressure chamber of the accumulator and the back pressure generating source are brought into communication with each other and a second position in which the communication is cut off to lower a pressure in the back pressure chamber. The changeover valve is arranged to be changed over from the second position to the first position when a hydraulic oil pressure in the hydraulic engaging element for the low-speed transmission train has exceeded a predetermined pressure.

Hydraulic bypass to back pressure chamber of a clutch accumulator

A control apparatus for a hydraulically operated vehicular transmission has a plurality of hydraulic engaging elements including a first hydraulic engaging element which is kept engaged in a plurality of transmission trains. The control apparatus has an accumulator which is connected, via a branched oil passage, to a working oil passage which is communicated with the first hydraulic engaging element. It also has a control valve which is disposed in the branched oil passage and which can be moved between a first position in which an upstream portion of the branched oil passage on a side of the first hydraulic engaging element and a downstream portion of the branched oil passage on a side of the accumulator are brought into communication with each other and a second position in which the communication is shut off. It further has an oil discharge passage which is connected to a second hydraulic engaging element when the second hydraulic engaging element is disengaged. This oil discharge passage is arranged to be connected to the downstream portion of the branched oil passage in the second position of the control valve.

Growing community of inventors

Wako, Japan

Kenichi Haraguchi