Hydraulic control apparatus of automatic transmission, and vehicle

1 . A hydraulic control apparatus of an automatic transmission that performs shifting of a vehicle by engaging and opening a hydraulic clutch, the hydraulic control apparatus comprising:

an electromagnetic proportional valve that is disposed in a hydraulic circuit and performs pressure regulation of operating oil supplied to the hydraulic clutch;

a pressure sensor that detects an oil pressure of the operating oil supplied to the hydraulic clutch; and

a control apparatus that executes filling of the hydraulic clutch with the operating oil and causes the hydraulic clutch to transition from an opened state to an engaged state by outputting, according to a control map stored in advance, a pulsed control current having a predetermined current value and a predetermined application time to the electromagnetic proportional valve, wherein

the control apparatus performs correction processing of correcting the predetermined current value and the predetermined application time at a predetermined timing such that the oil pressure of the operating oil supplied to the hydraulic clutch is within a predetermined target pressure range when the control apparatus outputs the pulsed control current to the electromagnetic proportional valve, the predetermined current value and the predetermined application time being stored in the control map.

2 . The hydraulic control apparatus according to claim 1 , wherein

the predetermined target pressure range is set using, as a reference, a pressure against a biasing force of a return spring of the hydraulic clutch.

3 . The hydraulic control apparatus according to claim 1 , wherein

the correction processing includes:

first processing of increasing the predetermined current value stored in the control map such that the oil pressure of the operating oil detected by the pressure sensor becomes higher than a lower limit value of the predetermined target pressure range when the pulsed control current is output to the electromagnetic proportional valve; and

second processing of decreasing the predetermined application time stored in the control map such that the oil pressure of the operating oil detected by the pressure sensor becomes lower than an upper limit value of the predetermined target pressure range when the pulsed control current is output to the electromagnetic proportional valve, and

the control apparatus executes, in the correction processing, the second processing after executing the first processing.

4 . The hydraulic control apparatus according to claim 1 , further comprising an oil temperature sensor that detects a temperature of the operating oil supplied to the hydraulic clutch, wherein:

the predetermined current value and the predetermined application time of the pulsed control current are stored in association with the temperature of the operating oil in the control map, and

the control apparatus acquires, in the correction processing, the temperature of the operating oil detected by the oil temperature sensor, and corrects, on the control map, the predetermined current value and the predetermined application time which correspond to the temperature.

5 . The hydraulic control apparatus according to claim 1 , wherein:

the control apparatus determines, based on an acceleration fluctuation of the vehicle or a rotation fluctuation of a vehicle axle of the vehicle, whether a shifting operation of the automatic transmission is in an abnormal state, the acceleration fluctuation or the rotation fluctuation being detected during the shifting operation of the automatic transmission, and

the control apparatus performs the correction processing in a case where the shifting operation of the automatic transmission is in the abnormal state.

6 . The hydraulic control apparatus according to claim 1 , wherein

when the control apparatus changes the hydraulic clutch from the opened state to the engaged state, the control apparatus is configured to sequentially execute:

a filling step of filling the hydraulic clutch with the operating oil by outputting the pulsed control current to the electromagnetic proportional valve,

a pressure-decreasing step of decreasing the oil pressure of the operating oil by decreasing a current value of a control current output to the electromagnetic proportional valve such that the current value in the pressure-decreasing step becomes smaller than the predetermined current value in the in the filling step, and

a pressure-increasing step of increasing the oil pressure of the operating oil such that the oil pressure becomes higher than the oil pressure in the filling step, by increasing a current value of a control current output to the electromagnetic proportional valve such that the current value in the pressure-increasing step becomes larger than the current value in the pressure-decreasing step, and by applying a stepped or ramped control current, to complete the engaged state of the hydraulic clutch.

7 . A vehicle, comprising the hydraulic control apparatus according to claim 1 .