| 摘要 |
PURPOSE:To reduce dispersion of individual speed change characteristic of each transmission in this kind of automatic transmission by changing accumulator back pressure to its high side when the time is longer than usual in response to speed change time and oil temperature, and to its low side when the time is shorter than usual in linearly inverse proportion to the oil temperature. CONSTITUTION:A speed change time detecting means 130 clocks the time TT from the mechanical connection change-over starting point to the terminating point at the speed change time of an automatic transmission. According to the speed change time TT, an accumulator pressure control means 130 updates the current value (electrification duty) applied to a pressure control valve SL6 in the shortening direction when the time TT is long, that is, in the direction of heightening accumulator back pressure, and in the lengthening direction when the time TT is short, that is, in the direction of lowering back pressure. Furthermore, in linearly inverse proportion to the transmission oil temperature detected by an oil temperature sensor 136, the accumulator back pressure is automatically and linearly regulated to make the speed change time TT substantially the fixed value. Speed change shock and engine blow-up caused by dispersion and oil temperature change are therefore practically prevented from occurring. |
