| 摘要 |
PURPOSE:To simplify an energization control system for an electromagnet which is an electromagnetic means used as a booster device, to reduce the cost thereof, by providing such an arrangement that a hydraulic pressure corresponding to the depressing force of a foot pedal is compared with the braking pressure, and the energization control system of the electromagnet is carried out in accordance with the result of the comparation. CONSTITUTION:When a pedal 1 is depressed, a hydraulic pressure corresponding to the depressing force is effected in a chamber 9 in a hydraulic converter device 8. By this hydraulic pressure a piston 14a is raised so that a pressure is effected in a chamber 12b, and this pressure is detected by a hydraulic pressure sensor 18 which issues a signal A to a controller 21. The controller 21 energizes an electromagnet 6 in accordance with the level of the signal A to drive an electromagnetic drive device 5 for operating a master cylinder 2. The output hydraulic pressure of the master cylinder 2 is introduced into a chamber 13a in the hydraulic converter device 8 to depress the piston 14b downward. Therefore, the pressure in the chamber 12b becomes zero so that the signal from the sensor 18 disappears to stop the electromagnetic device 8. Thereafter the operation of the electromagnetic device 8 is repeated by means of the hydraulic pressure acting upon the pistons 14a, 14b, thereby the braking pressure may be obtained in accordance with the depressing force of the foot pedal. |
