Abstract: The disc brake apparatus includes a disc brake having a parking brake mechanism operated by an electric motor as a drive source to mechanically hold a piston, which has been moved forward by a hydraulic pressure supplied from a hydraulic control unit into a caliper, in a braking position even after the hydraulic pressure is released; and a controller for supplying a predetermined amount of hydraulic pressure from the hydraulic control unit to the caliper, based on a parking-brake indicating signal from a parking brake switch and for operating the parking brake mechanism, wherein, in a case in which a brake pedal is being operated when a parking-brake indicating signal is input, the parking brake mechanism is operated in a state in which a hydraulic pressure in the caliper is at a predetermined pressure, after the operation of the brake pedal is finished, so as to reduce a hydraulic pressure required for a release of a brake pedal.

Abstract: A disk brake with a parking brake mechanism capable of exerting a large piston thrust required for operating a parking brake, without adversely affecting operation of a service brake. A parking brake mechanism 32, which is driven by an electric motor provided outside a housing 30, is incorporated in a caliper 14 in which a piston 26 is slidably disposed in a cylinder 24. The parking brake mechanism 32 is slidably fitted via a seal member 36 into the piston 26 and provided with a nut member 37 that is prevented from rotating relative to the piston 26 by engagement of a pin 48 and a pin hole 49; and a shaft 35 that is screwed into the nut member 37. During a service brake operation, the piston 26 alone is moved by a hydraulic pressure under a small piston thrust.

Abstract: There is provided a pneumatic booster having an ejector, which achieves space-saving and enables easy piping. An ejector 4 is provided within a constant-pressure chamber 3 formed in an outer shell 2. A connecting pipe 19 communicated with an outlet of a diffuser and a connecting pipe communicated with an inlet of a nozzle extend outward of the shell, and a suction port is open to the inside of the constant-pressure chamber 3 through a check valve. The connecting pipe 19 is communicated with the constant-pressure chamber 3 through a check valve 10, and is connected to a suction pipe of an engine (a source of a negative pressure). The connecting pipe on the inlet side of the nozzle is connected to an air cleaner (the atmosphere). A negative pressure is directly supplied from the connecting pipe 19 to the constant-pressure chamber 3 through the check valve 10. The ejector 4 is operated to supply a high degree of vacuum to the constant-pressure chamber 3 through the suction port.

Abstract: There is provided a pneumatic booster having an ejector, which achieves space-saving and enables easy piping.

Abstract: The present invention provides a brake booster that, although simple in construction, capable of adjusting the braking force derived by operation of a solenoid mechanism without worsening the braking response. In the brake booster according to the present invention, when a movable member (34) is shifted toward the rear side by electromagnetic force of a solenoid (31), the shifting movement is transmitted to a valve seat member (21) through pins (50) to open an atmospheric valve (27) through which air is introduced into a variable pressure chamber (9,10), whereby a pressure difference is created between the variable pressure chamber and a constant pressure chamber and generates booster output (thrust output force).

Abstract: The present invention provides a control booster which is capable of appropriately detecting a pedal-operated brake operation during an automatic brake operation. For moving a stop key from a position on a side of a rear-side abutment surface (where a reaction force of a switch acting on a switch operating rod and a spring force of a switch spring are balanced) toward an intermediate position, when the stop key is located on a side of the rear-side abutment surface, only a return force of the spring acts on a contact operating element of the switch. On the other hand, when the stop key moves toward the intermediate position, an abutment portion is separated from the contact operating element (that is, the switch operating rod moves in a direction for separation relative to the switch), so that no load is applied to the contact operating element.

Abstract: The present invention provides a booster in which magnitude of output can be adjusted also by an operation of a solenoid mechanism. An armature (13) is shifted to the right (in FIG. 1) in opposition to a returning spring by applying electricity to a solenoid (39), with the result that a space (80) on one end of the armature is communicated with a constant pressure chamber (5) through a passage (T3). When an electromagnetic force acting on the armature (13) exceeds a predetermined value, a distal end of a valve member (28) is shifted to the right (in FIG. 1) via a cylindrical member (31) to open an atmospheric valve (34), thereby introducing the atmosphere into a variable pressure chamber (6). The pressure in the variable pressure chamber is applied to the other end of the armature and the difference in the pressure tends to move the armature toward its home position.

Abstract: The present invention provides a control booster which is capable of appropriately detecting a pedal-operated brake operation during an automatic brake operation. For moving a stop key from a position on a side of a rear-side abutment surface (where a reaction force of a switch acting on a switch operating rod and a spring force of a switch spring are balanced) toward an intermediate position, when the stop key is located on a side of the rear-side abutment surface, only a return force of the spring acts on a contact operating element of the switch. On the other hand, when the stop key moves toward the intermediate position, an abutment portion is separated from the contact operating element (that is, the switch operating rod moves in a direction for separation relative to the switch), so that no load is applied to the contact operating element.

Abstract: The present invention provides a brake booster that, although simple in construction, capable of adjusting the braking force derived by operation of a solenoid mechanism without worsening the braking response. In the brake booster according to the present invention, when a movable member (34) is shifted toward the rear side by electromagnetic force of a solenoid (31), the shifting movement is transmitted to a valve seat member (21) through pins (50) to open an atmospheric valve (27) through which air is introduced into a variable pressure chamber (9,10), whereby a pressure difference is created between the variable pressure chamber and a constant pressure chamber and generates booster output (thrust output force).