Patent ID: 7306543
Filing Date: 2007-12-11
Classification: F16D,F16H,Y10T

Abstract:
1. An automatic transmission controller that controls an automatic transmission of a vehicle by supplying a pressure of a fluid to a friction element of the automatic transmission to engage the friction element, the automatic transmission controller comprising: an electronic control circuit that generates a control current; an electromagnetic valve that regulates a command pressure in accordance with the control current; and a pressure control valve that has a spool and is formed with a spool hole, the spool reciprocating in the spool hole in accordance with the command pressure to regulate the pressure supplied to the friction element, wherein in a standby state, when the friction element is in a disengaged state, the electronic control circuit generates an oscillating current as the control current so that the electromagnetic valve generates a standby command pressure as the command pressure to make the spool reciprocate in a range in which no pressure is supplied from the pressure control valve to the friction element.