Oil pressure control device of automatic speed change gear

Abstract

Abstract PURPOSE:To increase durability of a clutch by providing a rotation frequency detector for detecting synchronism of an input shaft and a gear train carrier and oil pressure supply switching valve for a friction clutch so that after a front clutch is completely engaged, the friction clutch is engaged so as to change speed smoothly. CONSTITUTION:A speed change gear train 100 is provided with rotational frequency detectors 332, 333 for detecting the synchronous rotational frequency of an input shaft 10 and a gear train carrier 23, and an oil pressure control device 340 is provided with a friction clutch control valve (switching valve) 230 for starting the supply of oil pressure to front, rear and friction (4th speed) clutches 11-13. During speed change from the second speed to the third speed, oil pressure supplied to the described one pair of clutches is controlled to be low by the oil pressure control device 340, and the supplied oil pressure is raised by detecting synchronism by detecting signals from the rotational frequency detectors 332, 333. Subsequently, the friction clutch switching valve 230 is switched by such rise in oil pressure to start the supply of oil pressure to the friction clutch 13. Thus, the front clutch 11 and the friction clutch 13 are not engaged at the same time so as to prevent generation of a shock by a speed change.

Inventors

• 👤 Takeo Hiramatsu
• 👤 平松　健男

Bibliographic Details