Abstract: A control apparatus of an automatic transmission, which includes a mechanical engaging mechanism functioning as a brake, includes a determination unit determining, when a selected gear is a lowest forward speed gear, and the mechanism is in a second state, whether to switch the mechanism to the first state, and a switching processing unit switching the mechanism to the first state based on a determination result. In the first state, only rotation of a predetermined rotational element provided in planetary gear mechanisms in a first direction is restricted. In the second state, rotation of the predetermined rotational element in both the first and second direction is restricted. The determination unit determines to switch the mechanism to the first state at least on condition that a driving force is larger than a predetermined driving force.

Abstract: A control apparatus of an automatic transmission, which includes a mechanical engaging mechanism functioning as a brake, includes a determination unit determining, when a selected gear is a lowest forward speed gear, and the mechanism is in a second state, whether to switch the mechanism to the first state, and a switching processing unit switching the mechanism to the first state based on a determination result. In the first state, only rotation of a predetermined rotational element provided in planetary gear mechanisms in a first direction is restricted. In the second state, rotation of the predetermined rotational element in both the first and second direction is restricted. The determination unit determines to switch the mechanism to the first state at least on condition that a driving force is larger than a predetermined driving force.

Abstract: A hydraulic control device for an automatic transmission is provided. The hydraulic control device can sets up any gear from a plurality of gears by causing any one of a plurality of frictional engagement elements to selectively carry out an engagement operation. The hydraulic control device includes: a regulator valve that regulates base oil pressure of hydraulic oil supplied from an oil pressure source; a relief valve provided in a lubricating oil passage connected from the regulator valve; and a line pressure switching section that sets up line pressure to low pressure to reduce the amount of lubricating oil in a region in which engagement hydraulic oil pressure does not require high engagement hydraulic oil pressure depending upon an operation state of a vehicle, and sets up the line pressure to high pressure when a target value of the engagement hydraulic oil pressure exceeds predetermined pressure.

Abstract: Lubricating oil passages extending toward a power transmission mechanism from a regulator valve to lubricate the power transmission mechanism include a first lubricating oil passage for supplying lubricating oil to a low clutch used to set up a low gear speed and a second lubricating oil passage for supplying lubricating oil with line pressure to the low clutch. A check valve for preventing the lubricating oil from flowing out from frictional engagement elements other than the low clutch when the second lubricating oil passage is selected, is provided on the first lubricating oil passage. An outflow preventing section for preventing the lubricating oil, supplied to the low clutch via the first lubricating oil passage, from flowing out from any open port of hydraulic control valves when the second lubricating oil passage is not selected, is provided on the second lubricating oil passage.

Abstract: A hydraulic control device for an automatic transmission is provided. The hydraulic control device can sets up any gear from a plurality of gears by causing any one of a plurality of frictional engagement elements to selectively carry out an engagement operation. The hydraulic control device includes: a regulator valve that regulates base oil pressure of hydraulic oil supplied from an oil pressure source; a relief valve provided in a lubricating oil passage connected from the regulator valve; and a line pressure switching section that sets up line pressure to low pressure to reduce the amount of lubricating oil in a region in which engagement hydraulic oil pressure does not require high engagement hydraulic oil pressure depending upon an operation state of a vehicle, and sets up the line pressure to high pressure when a target value of the engagement hydraulic oil pressure exceeds predetermined pressure.

Abstract: A control apparatus for a hydraulically operated vehicular transmission includes a orifice, a bypass path bypassing the orifice and a switching valve provided in the bypass path. The orifice and bypass path are provided in an hydraulic oil supplying path to a hydraulic pressure coupling element provided in said hydraulically operated vehicular transmission. The switching valve shuts off said bypass path in association with the throttle of an engine at a low opening time when a throttle opening degree is equal to or lower than a first predetermined value and at a high opening time when the throttle opening degree is equal to or higher than a second predetermined value which is higher than the first predetermined value.

Abstract: A control apparatus for a hydraulically operated vehicular transmission having a plurality of speed change steps includes a shift valve unit controlling the supplying of hydraulic oil to and discharging of hydraulic oil from hydraulic pressure coupling elements for the respective speed change steps, a throttle hydraulic pressure signal outputting device which outputs a throttle hydraulic pressure signal which is applied to switch the shift valve unit, according to a throttle opening degree of an engine and an accumulator connected to an input oil path through which the throttle hydraulic pressure signal is applied to the shift valve unit.

Abstract: There are respectively provided control valves 15, 16 in hydraulic oil paths L11, L12 for inputting governor pressure PV into shift valves 11.sub.1, 11.sub.2, 11.sub.3. In the control valves 15, 16, there are provided first pressure chambers 15g, 16g pushing the spools 15a, 16a of the control valves 15, 16 onto the closing position side. At position "D.sub.3 " or "2", hydraulic pressure is inputted into the first pressure chambers 15g, 16g, so that the spools 15a, 16a can be changed over to the closing position, and the input of governor pressure PV into the shift valves 11.sub.1, 11.sub.2, 11.sub.3 is stopped so that the shift valves can be changed over to the low speed position. In the control valves 15, 16, there are provided second pressure chambers 15h, 16h pushing the spools 15a, 16a onto the opening position side, and governor pressure PV is inputted into the second pressure chambers 15h, 16h.