Patent ID: 8517877

Claim:
A hydraulic control apparatus for an automatic transmission, including an oil pressure generation source, a line pressure adjustment valve that adjusts an oil pressure of the oil pressure generation source to a line pressure, a modulator pressure adjustment valve that adjusts the line pressure to a modulator pressure that is constant and lower than the line pressure, a plurality of working pressure adjustment valves that adjust the line pressure to respective working pressures and that directly supply the working pressures to respective hydraulic servos for a plurality of friction engagement elements, and a maximum pressure feed valve that feeds to the line pressure adjustment valve a maximum working pressure among the working pressures adjusted by the plurality of working pressure adjustment valves, the line pressure adjustment valve using the working pressure from the maximum pressure feed valve as a control pressure to adjust the line pressure on the basis of the control pressure, the hydraulic control apparatus comprising: a gain switching section that switches a gain of the line pressure adjustment valve between 1 or more and less than 1; and a source pressure switching valve that switches a source pressure for the working pressure adjustment valve that outputs the control pressure for the line pressure adjustment valve between the line pressure and the modulator pressure, wherein the source pressure switching valve switches the source pressure for the working pressure adjustment valve to the line pressure when the gain switching section switches the gain of the line pressure adjustment valve to less than 1, and the source pressure switching valve switches the source pressure for the working pressure adjustment valve to the modulator pressure when the gain switching section switches the gain of the line pressure adjustment valve to 1 or more.