Control device for automatic transmission

Abstract

Abstract PURPOSE: To increase the speed of fail detection for an automatic transmission, and also prevent a shock and the lowering of durability by fails. CONSTITUTION: A control device for automatic transmission is provided with a selector valve 6 which applies a signal pressure for setting pressure setting level selectively to a pressure control valve 3 and the other control, valves 5. Also it is provided with an error detecting means 7 which, when the transmission is speed changed to a stage set by a frictional engagement device 1 to be engaged by the supply of controlled hydraulic pressure, detects both an controlled hydraulic pressure error of engagement pressure of the frictional engagement device 1 and an erroneous operation based on the supply of signal pressure to the control valve 5. In addition, it is provided with a speed change stage prohibiting means 8 which prohibits a speed change stage when this error detecting means 1 detects at least either of the controlled pressure error and erroneous operation.

Inventors

• 👤 Atsushi Tabata
• 👤 淳 田端
• 👤 Yasuo Hojo
• 👤 康夫 北條
• 👤 Hideki Miyata
• 👤 英樹 宮田
• 👤 Akira Fukatsu
• 👤 彰 深津

Bibliographic Details