Abstract: A double piping type hydraulic pressure control device in which hydraulic pressure control of a hydraulic pressure channel A is transmitted to another channel B in such a manner that the hydraulic pressure to be exerted on a balance piston for hydraulic pressure control is obtained solely from the hydraulic pressures of the two output chambers while two input hydraulic pressures are arranged to have nothing to do with the control action.

Abstract: In a pin-slide type disc brake, the caliper of the disc brake is prevented from dropping or turning on a slide pin due to its own weight during replacement of the friction pads of the disc brake by providing a fitting hole in a part of a support straddling the disc in the radial direction of the disc and in the vicinity of a caliper guide mechanism located on the upper side of the support. A rigid rod is fitted into the hole and arranged to have, for example, the inner wall of the disc straddling portion of the caliper come to engage it to thus prevent the caliper from dropping when it is turned about the slide pin.