Negative pressure booster for speed change

Abstract

Abstract PURPOSE:To give a favorable shift feeling to a driver by actuating a pressure difference in accordance with thrust of a booster piston on a first or a second reaction force pistons as a reaction force during the shift of a transmission. CONSTITUTION:When an input member 11 is, for example, shifted to the left by a gear shift lever 12, a poppet valve 221 is opened and then a contact ring 371 opens a flat valve 311. Consequently, a reaction force chamber 141 is blocked from an air chamber 131 and communicated through to a negative pressure chamber 33, so that negative pressure of a negative pressure source S is supplied to the chamber 14 and an actuation chamber 31. Accordingly, as a large pressure difference is generated between the actuation chambers 31, 32, a booster piston 2 power-actuates to the side of the chamber 31 of low pressure and follows movement of the member 11 by this pressure difference, and the booster piston 2 gives a shift motion to a shift arm 39 through an output member 38. During the above shift of the piston 2, a pressure difference is also generated between the air chamber 131 and the chamber 141, and accordingly, this pressure difference works on a piston 71 as a reaction force to the right and is transmitted to the member 11, and accordingly, a driver can obtain a favorable shift feeling.

Inventors

• 👤 Kiyotaka Kobayashi
• 👤 清孝 小林
• 👤 Takayoshi Shinohara
• 👤 孝義 篠原

Bibliographic Details