Hydraulic controller of automatic transmission gear

Abstract

Abstract PURPOSE: To prevent a shift timing valve from causing underlap and engine blow- up when oil temperature drops, by setting a thermal controller for controlling the spring force of the valve in accordance with the oil temperature. CONSTITUTION: A shift valve 4 is fed with line pressure from a port 13. This line pressure is fed to a high clutch 2 from a port 14 through a shift timing valve 7, when the valve 4 is positioned at 4A, and from a port 15 to a low clutch 1, when the valve 4 is positioned at 4B. Accumulators 18, 19 are connected with oil passages to the clutches 1, 2 and an oil temperature compensating valve 38 is set in an oil passage 38 which introduces a preset level of control oil pressure Pc to the valve 7. The compensating valve 38 is equipped with a bimetal valve 46 for releasing a valve port 44 when oil temeperature drops below a preset level and cuts the control oil pressure off to the valve 7, its attitude being altered to 38A. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Yoshio Shindo
• 👤 Hiroshi Ito

Bibliographic Details