초록 ▼

A system for controlling oil pressure of an automatic vehicle transmission having a plurality of fictional engaging elements (K1 ,K2,K3,B 1 ,B2) installed in the transmission for establishing a gear, a plurality of solenoid valves (SA and SE) at least one (SA) of which opens to supply the pressurize

A system for controlling oil pressure of an automatic vehicle transmission having a plurality of fictional engaging elements (K1 ,K2,K3,B 1 ,B2) installed in the transmission for establishing a gear, a plurality of solenoid valves (SA and SE) at least one (SA) of which opens to supply the pressurized oil to at least one (K1) of the frictional engaging elements. The system also as a manual valve (20) whose spool moves in response to the selection of the selector lever for supplying the pressurized oil to the frictional engaging element bypassing the solenoid valve when the shift lever selects another gear range (1) in case of solenoid valve failure, and an underdrive engage control valve (30, 96) placed between the frictional engaging element and the switching valve for regulating pressure of the pressurized oil to be supplied to the frictional engaging. element in response to the pressurized oil outputted from the solenoid valve. In the system the underdrive engage control valve regulates the pressure of the pressurized oil to be supplied to the frictional engaging element in response to the pressurized oil supplied from the switching valve.

대표청구항 ▼

[ What is claimed is:] [1.] A system for controlling oil pressure of an automatic transmission mounted on a vehicle, including:a selector lever for selecting one among a plurality of gear ranges in the transmission;a plurality of frictional engaging elements installed in the transmission for establi

[ What is claimed is:] [1.] A system for controlling oil pressure of an automatic transmission mounted on a vehicle, including:a selector lever for selecting one among a plurality of gear ranges in the transmission;a plurality of frictional engaging elements installed in the transmission for establishing a gear in a gear train in the selected gear range;an oil pump for pumping oil from an oil reservoir to generate pressurized oil;a plurality of solenoid valves at least one of which opens to supply the pressurized oil to at least one of the frictional engaging elements;a switching valve whose spool moves in response to the selection of the selector lever for supplying the pressurized oil to the frictional engaging element outputted from the solenoid valve when the shift lever selects one gear range, while supplying the pressurized oil to the frictional engaging element bypassing the solenoid valve when the selector lever selects another gear range; anda regulating valve placed between the frictional engaging element and the switching valve for regulating pressure of the pressurized oil to be supplied to the frictional engaging element in response to the pressurized oil outputted from the solenoid valve;wherein the improvement comprises:the regulating valve regulates the pressure of the pressurized oil to be supplied to the frictional engaging element in response to the pressurized oil supplied from the switching valve.