Patent attributes
A hydraulic pressurizer system comprises a drive source, which drives a hybrid vehicle, a mechanical oil pump, which is driven by the drive source, an electrical motor, which is activated by a 12V battery, an electrical oil pump, which is driven by the electrical motor, and a control unit, which activates the electrical motor. The pressurizer further comprises a ratio-change mechanism, which is activated by hydraulic oil supplied by the mechanical oil pump and by the electrical oil pump to establish a speed change ratio, at which the rotational driving force of the drive source is transmitted to wheels with a rotational speed change. The control unit memorizes a characteristic value, which is specified from the temperature of the hydraulic oil and from the rotational speed of the electrical motor, and a threshold value for the rotational speed of the electrical motor, which threshold value corresponds to the characteristic value.
