Abnormal condition detecting apparatus and safety apparatus for hydraulic brake boosting system

An abnormal condition detecting apparatus for a hydraulic brake boosting system arranged such that hydraulic pressure in an accumulator accumulated by a pump is used to boost the operation of a brake operating member so as to generate braking force, said apparatus comprising:

• pressure-gradient calculating means for calculating a gradient of the pressure depression which is changed in the depression of hydraulic pressure in an accumulator in a predetermined time after the operation of the pump has been interrupted;
• and alarm-signal generating means for transmitting, to an alarm unit, an alarm signal when the gradient of the pressure depression is larger than a predetermined set value, wherein when the gradient of the pressure depression of the pressure discharged from the pump is larger than the set value after the operation of the pump has been interrupted, a determination is made that an abnormal condition has been encountered and wherein said determination of an abnormal condition is inhibited during a braking operation.

An abnormal condition detecting apparatus for a hydraulic brake boosting system arranged such that hydraulic pressure in an accumulator accumulated by a pump is used to boost the operation of a brake operating member so as to generate braking force, said apparatus comprising:

• pressure-gradient calculating means for calculating a gradient of the pressure rise which is changed in the rise in pressure discharged from a pump or hydraulic pressure in an accumulator in a predetermined time during the operation of the pump;
• and alarm-signal generating means for transmitting, to an alarm unit, an alarm signal when the gradient of the pressure rise is smaller than a predetermined first set value or when the gradient of the pressure depression is larger than a predetermined second set value during the operation of the pump, wherein when the gradient of the pressure rise of the pressure discharged from the pump or the hydraulic pressure in the accumulator is smaller than the first set value during the operation of the pump or when the gradient of the pressure depression of the hydraulic pressure in the accumulator after the operation of the pump has been interrupted is larger than the second set value, a determination is made that an abnormal condition has been encountered, and wherein said determination of an abnormal condition is inhibited during a braking operation.

An abnormal condition detecting apparatus for a hydraulic brake boosting system arranged such that hydraulic pressure in an accumulator accumulated by a pump is used to boost the operation of a brake operating member so as to generate braking force, said apparatus comprising:

• pressure-gradient calculating means for calculating a gradient of the pressure rise which is changed in the rise in pressure discharged from a pump or hydraulic pressure in an accumulator in a predetermined time during the operation of the pump;
• and alarm-signal generating means for transmitting, to an alarm unit, an alarm signal when the gradient of the pressure rise is larger than a predetermined set value, wherein when the gradient of the pressure rise in the pressure discharged from the pump is larger than the set value during the operation of the pump, a determination is made that an abnormal condition has been encountered, and wherein said determination of an abnormal condition is inhibited during a braking operation.