Hydraulic control system of an automatic transmission

Abstract

Abstract A HYDRAULIC SERVO MECHANISM FOR THE FIRST TWO SPEEDS OF A THREE SPEED TRANSMISSION. PRESSURE ON THE CLUTCHES AND BRAKES FOR THE FIRST TWO SPEEDS IS SELECTIVELY APPLIED ACCORDING TO THE VALVE SPOOL POSITION OF A ONE-TWO SHIFT VALVE WHICH HAS GOVERNOR PRESSURE LINE CONNECTED TO ONE END AND PRESSURE MEANS CONNECTED TO THE OTHER END. THESE PRESSURE MEANS SUPPLY EITHER LINE PRESSURE OR THROTTLE PRESSURE DEPENDING ON A CHECK VALVE REGULATING SAID PRESSURE MEANS. ACCORDING TO THE PRESENT INVENTION, THIS PRESSURE MEANS HAS A PRESSURE REDUCING VALVE HAVING AN OUTPUT LINE WHICH COUPLES THE CHECK VALVE TO THE PRESSURE INPUT LINE WHICH COUPLES THE CHECK VALVE TO THE PRESSURE REDUCING VALVE. THE INTERCONNECTION OF THESE OUTPUT AND INPUT LINES WITHIN SAID PRESSURE REDUCING VALVE IS REGULATED BY SPRING BIASED VALVE SPOOL MEANS. COUPLED TO THE PRESSURE REDUCING VALVE IS AN ADJUSTABLE PILOT VALVE WHICH CONTROLS THE PRESSURE IN THE PRESSURE REDUCING VALVE. THUS, THE PRESSURE REDUCING VALVE PERMITS ONLY A PREDETERMINED OUTPUT TO BE FED TO SAID ONE-TWO SPEED VALVE AND THE ONE-TWO SPEED VALVE IS PREVENTED FROM HAVING FED TO IT AN INPUT GREATER THAN THE PREDETERMINED INPUT.

Inventors

• 👤 Keiji Kogaki

Bibliographic Details