Abstract: A brake cylinder for pneumatic vehicle brakes, especially for commercial vehicles, includes in addition to a pneumatic locking mechanism, a manual release mechanism for manually releasing the spring brake section, and a device designed to visually recognize the manual release condition of the spring brake section outside of the housing.

Abstract: A brake cylinder for pneumatically actuated vehicle brakes, especially for commercial vehicles, includes a housing. The housing is divided into two chambers by a piston, one of the chambers being used as a pressure chamber for actuating an operating brake section, and a cylinder spring of a spring-loaded brake section being arranged in the other chamber on the opposite side of the piston. The cylinder spring acts on another spring-loaded piston in the chamber, which can be blocked in relation to the first piston by a pneumatically actuated locking mechanism. The other spring-loaded piston is released from the first piston by a releasing action of the blocking mechanism, and is connected to a piston rod for actuating the vehicle brake. Following release of the blocking mechanism, the cylinder spring acts between the two pistons and moves them in relation to each other during a parking braking operation.

Abstract: The present invention relates to a blocking mechanism for a parking lock of a shaft in a motor vehicle. The blocking mechanism includes a pawl pivotable about a pivot axis and which, in a blocked position, engages into at least one latch cut-out of a ratchet wheel connected to the shaft. The blocking mechanism includes an actuating mechanism having an actuating device for moving an actuation slider. The pawl is pivotable by a movement of the actuation slider. The actuation slider includes a first U-shaped component and a second U-shaped component which each have two side sections and a transverse section connecting the side sections. The first component and the second component are plugged into one another in opposite directions such that the transverse section of the one component at least partly closes the open end of the U shape of the component and vice versa.

Abstract: A resistance mechanism used in motor vehicle accelerator pedals for generating an opposing mechanical force. The resistance mechanism includes a piston adapted for movement in a housing between a first detent or stop position and a second compressed position. The piston includes an exterior surface defining at least one recess. A spring, located in the housing, biases the piston in the first position. A pin in the housing is seated in the recess of the piston in the first position of the piston. A retainer is adapted to retain the pin in the piston recess in the first position of the piston. The piston is adapted for movement between the first position and a second compressed position in which the pin is forced out of the recess and into the housing.

Abstract: A housing has upper and lower faces, front and rear faces and side faces. A vertical bore extends through the housing between the upper and lower faces. A horizontal bore extends into the housing from the front face. The horizontal bore further extends to the vertical bore. A ball valve is positioned within the vertical bore laterally spaced from the horizontal bore. The ball valve is rotatable between open and closed orientations. A lock cylinder is located within the vertical bore. The lock cylinder has an exposed end with a keyway. The lock cylinder has an unexposed end with a connector clip. The connector clip couples the lock cylinder and the ball.

Abstract: A brake cylinder is provided for vehicle brakes, in particular for commercial vehicles brakes, that is equipped with a brake cylinder housing, in which a spring-loaded piston, a service brake piston, a spring-loaded spring and a piston return spring are arranged. The brake cylinder is simple to construct and extremely compact. The spring-loaded piston is in a primary chamber of the brake cylinder and is arranged between the service brake piston and a front side of the brake cylinder housing having the compressed air connections.

Abstract: An object of the present invention is to provide a disk brake having excellent responsiveness. A rotation preventing mechanism 34A prevents a rotation of a carrier 41 (one output member) in a direction causing a piston 12 to return. An internal gear 46 (the other output member) rotates by a predetermined degree to act on the rotation preventing mechanism 34A. When the motor 38 causes a sun gear (input member) to rotate such that the piston 12 moves in a return direction, a rotation of the internal gear 46 according to the rotation of the sun gear 44 releases rotation prevention of the rotation preventing mechanism 34A to the carrier 41. It is possible to release the parking brake without use of a worm gear which is used in the conventional arts for holding a thrust force (self-holding). As a result, it is possible to quickly release the parking brake, and therefore a driver can start to run without delay after parking brake release, whereby the responsiveness is improved.

Abstract: The present invention includes a hydraulic brake device 4, 5 that generates a braking force corresponding to an operation of a brake pedal 1 performed while the vehicle is traveling, a brake lock means 6 for applying a hydraulic lock on the hydraulic brake device 4, 5 and releasing the hydraulic lock, a brake pedal operation detection means 22 for detecting an operation of the brake pedal 1, and a control means 10 for controlling the brake lock means 6 so as to apply the hydraulic lock on the hydraulic brake device 4, 5 upon detecting via the brake pedal operation detection means 22 a predetermined depressing operation of the brake pedal 1.

Abstract: When a brake force is generated by a service brake in accordance with the depression of a brake pedal by a driver, a brake force generated by an electric parking brake is reduced when lock control is performed, taking the brake force generated by the service brake into consideration. More specifically, a target motor current value increase amount is corrected such that as the brake force generated by the service brake becomes larger, the target motor current value increase amount becomes smaller. Thus, when brake force is generated by the electric parking brake and the service brake compensates for the brake force, it is possible to inhibit generation of a brake force larger than necessary.

Abstract: A device (20) has an electrically-operated brake (37) and a manually-operated auxiliary brake (27). The electrically-operated brake includes a coil (70), a core (68), an armature (69), and an alternating series of friction pads (74) and brake disks (75), that are arranged to be compressed between the housing and the armature. The shaft brake (27) includes a collar (22) mounted on the housing for combined axial and rotative movement relative thereto, a first interlock portion (106, 110) mounted on the shaft (24), an annular member (84) surrounding the shaft and having a second interlock portion (85) and a spring (124) urging the member to move toward the shaft. The collar (22) is adapted to be selectively moved relative to the housing between a first portion at which the first (106, 110) and second (85) interlock portions are physically engaged with one another, and a second position at which the first (106, 110) and second (85) interlock portions are physically separated from one another.

Abstract: A motor current detecting device is provided in a parking brake control system for detecting electric current flowing through an electric motor. And current supply to the electric motor is stopped in case of carrying out a parking brake releasing operation, when a time period in which a differentiated value of the electric current flowing through the electric motor is smaller than a predetermined threshold value exceeds a predetermined time. As a result, a partial braking condition, in which parking brake force partly remains even after the parking brake releasing operation, and which is caused by, for example, the elongation of the brake cable is prevented.

Abstract: A railway brake cylinder includes a body (11?); a piston (13?) mobile relative to the body (11?) to act on a brake linkage and delimiting with the body (11?) a pressure chamber (10?) adapted to be supplied by a pneumatic pressure agent source; an auxiliary actuating member (26?) mobile relative to the body (11?) and the piston (13?), mechanically connected to manual operating elements to cause it to occupy either a rest position in which it is away from the piston (13?) or a pushing position in which it is in contact with the piston (13?); two orifices (73?, 51?) in fluid communication with the chamber (10?) and the atmosphere, respectively; and selective connecting elements (28?) between the two orifices (73?, 51?), the elements (28?) being mechanically connected to the auxiliary actuating member.

Abstract: A parking brake assembly for a railway car includes a ratchet mounted for rotation on a threaded piston rod of a brake actuator and a holding pawl engageable with the ratchet for maintaining a push rod of the parking brake assembly to apply braking force when the air pressure is lost in the brake pipe and releasing the push rod to accordingly release the braking force when the supply of air pressure in the brake pipe is restored. An operating lever and a cylinder connected thereto are provided for selectively rotating the holding pawl. Valve is provided for supplying air pressure to and evacuating it from the cylinder. Release mechanism is provided for manually releasing the braking force. The parking brake assembly is employed with either truck-mounted or carbody-mounted braking system.

Abstract: The present invention relates to an actuation system for a parking brake of a motor vehicle, comprising a foot or a hand-actuated manual actuation means (10) for tightening of the parking brake, wherein the parking brake is purely mechanically tightened via the actuation means, a locking mechanism (20) for tightening and releasing of the parking brake, wherein the actuation means (10) and the locking mechanism (20) are arranged at different positions of the motor vehicle, respectively.

Abstract: An electronic parking brake apparatus may include a driving member coupled to and actuating a parking cable, a case in which the driving member is housed, a cable ferrule disposed outside the case and coupled to a portion of the parking cable therethrough, wherein the cable ferrule is biased toward the case by the parking cable when the driving member actuates the parking cable, and a sensing member interposed between the case and the cable ferrule and measuring tension of the parking cable.

Abstract: A cargo carrying vehicle has a towing unit and a storage unit defining a cargo space. The towing unit is operable to: a) advance the storage unit; and b) generate electrical power for operating at least one component on the vehicle. An input is provided for external power to be supplied to at least one of: a) charge; and b) operate the at least one component. A safety system has first and second states. With the safety system in the first state, with no external power supplied to the external power input, the towing unit can be operated to advance the storage unit. With the safety system in the second state, with external power supplied to the eternal power input, the towing unit cannot be operated to advance the storage unit.

Abstract: Disclosed is an electric parking brake. The electric parking brake includes a motor which forms torque through an electric device, multi-stage gears coupled with the motor, a gear wheel which is mechanically linked with the multi-stage gears, a screw nut which has a hollow structure, and is integrally formed with an inner circumferential surface of the gear wheel, a spindle geared with an inner circumferential surface of the screw nut to move in a shaft direction according to rotation of the gear wheel, a parking cable linked with the spindle at an outlet side of the spindle remote from the gear wheel, a stopper member fixed to an outer circumferential surface of a second end opposite to a first end of the spindle linked with the parking cable to prevent the spindle from excessively rotating when breaking is released. In the electric parking brake, the stopper member is fixed on the outer circumferential surface of an end opposite to one end of the spindle linked with the parking cable.

Abstract: In a pull arrangement including a housing with a guide structure movably supporting a carrier element which has a park position at one end of the guide structure and a rest position at the other end and a reversing structure is provided at the other end of the guide structure and a tension spring extending around the reversing structure is connected with one end to the carrier element and the opposite end to the housing for moving the carrier element to the end position, the tension spring comprises an area of high spring stiffness where it extends around the reversing structure and an area of low spring stiffness where the spring is connected to the housing away from the reversing structure.

Abstract: The disc brake device comprises a piston (5) designed to press a pad (8) against a disc (2) when said piston is subjected to a first force along a first axis (z?z) in a direction directed from the piston toward the pad. A first plate (12, 13) is inserted between a first surface (52) of the piston (5) and the pad (8) and designed to generate a second force along the first axis (z?z) in a direction directed from the pad toward the piston when the pad (8) is caused to move as a result of rotation of the disc (2.

Abstract: A brake cylinder for pneumatic vehicle brakes, especially for utility vehicles includes a spring brake section for carrying out parking brake actions by way of a brake spring, and a service brake section for carrying out pneumatic service brake actions. The spring brake section and the service brake section are combined in one housing as a structural unit. The housing is subdivided by a piston into two compartments, one compartment of the two being used as the pressure compartment for actuating the service brake section, and the brake spring of the spring section being arranged in the other compartment on the opposite end of the piston. The brake spring acts upon an additional spring piston in the compartment, which can be locked relative to the piston by a pneumatic locking mechanism and can be released therefrom by releasing the locking mechanism. The spring piston is connected to a piston rod directly or via additional elements to actuate the vehicle brake.

Abstract: While driving one motor, an electronic wedge brake (EWB) system according to an embodiment of the present invention implements a main braking function by self-energizing caused by a wedge operation. Since only one motor is used, it is possible to reduce the number of parts and to simplify the structure. Further, the electronic wedge brake system implements various functions, such as a function for maintaining a set clearance of a pad, a wheel lock prevention function, and an EPB function by using a solenoid interlocked with a NSL (Non-Self Locking) type screw that is moved in an axial direction and supports an axial reaction force transmitted from a pad. Furthermore, a NSL (Non-Self Locking) type push rod shaft, which supports the axial reaction force, is constrained using power of the motor during park braking, and accordingly, even when the solenoid is turned off, it is possible to stably and reliably park a vehicle.

Abstract: A disk brake for a vehicle, includes: an electric motor which has a motor shaft provided with an armature and which is attached to a caliper body so as to exhibit a power for urging a friction pad toward a disk rotor; and a Hall IC for detecting a rotational angle of the electric motor. The Hall IC is disposed within the electric motor so as to be located on an outer side of a pulser mounted on the motor shaft, and is retained by a motor case of the electric motor and a sensor cover made of a synthetic resin and detachably attached to the motor case. Thus, it is possible to reduce the number of parts by eliminating a special sealing measure.

Abstract: The invention relates to a selective freewheeling mechanism for developing an electromechanical vehicle brake (service brake) into a parking brake. The freewheeling mechanism according to the invention has an outer ring and a locking element cage which are configured as an electric motor with a rotor and a stator. The rotor and stator can be swiveled in relation to each other when a coil is supplied with current. Due to a symmetric design, the freewheeling mechanism is advantageously insensitive to acceleration forces.

Abstract: The invention relates to a brake disk lock having an actuable housing shell, a support section, an engagement hoop and a securing section, with the support section and the engagement hoop bounding a receiving gap for the receiving of a brake disk, with the housing shell being arranged on the same side as the support section with respect to the receiving gap and being movably supported at the support section and with the housing shell, the support section and the securing section cooperating with one another such that the housing shell is movable from a release position into a securing position by a movement of the housing shell relative to the support section in the direction of the receiving gap in order to close the receiving gap by means of the securing section.

Abstract: The invention relates to a brake disk lock having a receiving gap for the receiving of a brake disk, comprising: a securing section for the closing of the receiving gap, an alarm device for the output of an alarm signal, a movable brake disk recognition device, a pressure switch having a contact element which is movable against the spring force of a first spring means by the brake disk recognition device to activate the alarm device, and an actuation section which is movable out of a release position into a securing position to close the receiving gap by means of the securing section.

Abstract: The invention is a electromechanical locking device for a brake piston of a hydraulically actuated wheel brake. The locking device is disposed at least in some portions in the interior of a hollow-cylindrical brake piston. This interior of the brake piston is filled with hydraulic pressure fluid and in the event of brake actuation is subjected to pressure. The invention includes a filler piece and a coupling element, which reduce the pressure-fluid-filled volume of the brake piston, prevent blocking of the locking device in its terminal positions, and make it possible for the two terminal positions of the locking device to be detected and evaluated by an electronic control unit.

Abstract: A driving device for a parking brake system includes a casing shift member, a brake cable and a driving member. The casing shift member includes a cable casing. The brake cable is mounted through the cable casing. The driving member has a driving unit connected to and driving the casing shift member to perform a longitudinal motion. Thus the cable casing applies a force on the brake cable so as to perform a brake work. Because the brake cable is tightened with the force provided by the cable casing, the brake cable is only bent slightly. Thus the curvature of the brake cable is small. That prevents the brake cable from being damaged and prolongs a life span of the brake cable. Moreover, a mechanical efficiency of the driving device is improved because the brake cable is tightened with the force provided by the cable casing.

Abstract: A locking device for an adjustment fitting of a vehicle seat includes a locking cam rotatable about a first rotational axis and a locking pawl rotatable about a second rotational axis. The locking device is settable into a locking position and a release position. The locking cam comprises one piece having a first locking region and a first safety region. The locking pawl has a second locking region and a second safety region. The first and second locking regions contact one another in the locking position of the device, and the first and second safety regions lie opposite one another or contact one another in the locking position.

Abstract: A brake disk lock having a lock body which has a first housing section and a second housing section which bound a receiving gap for the reception of a brake disk in a typically U-shaped arrangement. A locking bolt is provided at the first housing section and is movable along a closing direction from a release position into a closed position. In the closed position, the locking bolt engages into an engagement opening of the second housing section and closes the receiving gap. The closing direction of the locking bolt is aligned obliquely to the receiving gap of the lock body at an angle different from 90°.

Abstract: A fixing device for an anti-slip cable locker is disclosed. The fixing device provides a connection such that after the cable is engaged, and a single screw action, the cable can be locked after engagement, and therefore, article hooked to the locker will be securedly locked. The fixing device allows a quick installation, rapid engagement with the cable locker and provides anti-slip from the cable locker.

Abstract: In a vehicle parking system, when a selected shift position is changed between Park and a shift position other than Park, if both an electric motor of an electric parking lock mechanism and an electric motor of an electric parking brake mechanism are operated, these electric motors are started in such a manner that the times at which striking currents supplied to these electric motors reach their peaks are staggered.

Abstract: The invention relates to an electromechanical disk brake which has a switchable freewheel in order to be configured as a parking brake. The switchable freewheel includes a clamping roller freewheel having rollers for locking a motor shaft of an electric motor of the brake. A locating bearing of the motor shaft of an electric motor, and the freewheel are accommodated on a cover of a housing of the electric motor, and all the electric connections of the disc brake are routed via the cover. The number of components used can be reduced considerably by the integrated design. Moreover, the positional tolerances of the freewheel in relation to the motor shaft can be reduced with the aid of the invention.

Abstract: The invention relates to a combination cylinder including a service brake cylinder as an active service brake with at least one pressure-medium-actuated service brake piston which actuates a brake mechanism via a service brake piston rod, and a spring store brake cylinder as a passive parking brake with a spring store brake piston which is actuated by pressure medium counter to the action of at least one store spring, with the spring store brake piston transmitting the force of the at least one store spring to the service brake piston rod by a force-transmitting gearing in the parking braking situation. The invention provides for the gearing to be designed such that the movements of the spring store brake piston and of the service brake piston rod are coaxial and the force transmission ratio becomes greater with progressive stroke of the spring store brake piston.

Abstract: A power drive assembly for a rear lift gate assembly of a vehicle includes a screw drive having a screw member and a clutch supported by the screw member.

Abstract: The present invention relates to parking brake lever system 1 for manually tightening and releasing of at least one brake cable 90, wherein the parking brake lever system 1 comprises at least one rotation arm 10, 12 pivotably supported at a fixed support 50, wherein the rotation arm 10, 12 is connected to the brake cable 90, and at least one actuation lever 20, 22, which at a first end thereof is pivotably connected to the rotation arm 10, 12 and which at a second end thereof is rigidly connected to a hand grip 40, wherein the actuation lever 20, 22 is slidingly supported at the fixed support 50, such that the hand grip 40 defines a curved path during actuation of the parking brake lever system 1.

Abstract: There is provided an electromechanical actuator for a parking brake system of a vehicle, including an electric motor, reduction gear train associated with the motor for transmitting motion from the motor to a single power transmission chain sprocket, one power transmission chain section drivable by the sprocket partly encircling one sheave, rotatably mounted on a free longitudinally movable pulley block, an end of the power transmission chain being attached to a first stationary anchor point, and a connector connecting the pulley block to the vehicle's parking brake system.

Abstract: An all terrain vehicle parking brake for after market installation on an ATV, UTV, RUV or MUV that relies on placing the vehicle shift lever in a park position to hold the vehicle on a hill. The parking brake includes a brake handle that is mounted to the vehicle dash board to pivot between brake engaged and disengaged positions, extending and retracting a linkage that connects and disconnects through a straight sleeve, with the linkage connecting to a rod end bearing that connected to a brake pedal arm, depressing the brake pedal when an operator activates the parking brake.

Abstract: A clamp device inserted between two parts can prevent a relative movement between a brake disc and a brake caliper of a vehicle brake. The device includes two plates, with adjustable separation by way of at least two rollers running against each other and rolling on roller surfaces on facing inner sides of the plates. When the rollers are located in the region of a first section of the roller surfaces, the separation of the plates for bringing about clamping in an extended state is greater than the separation adopted by the plates to generate clamping in a withdrawn state when the rollers are located in the region of a second section of the roller surfaces. The position of the rollers relative to the roller surfaces may be altered by an actuator.

Abstract: A slack adjustment system for a disk brake includes a biasing member to adjust slack in a brake system. The biasing member operates independently of pressure applied to a brake actuator. A locking member prevents adjustment when adjustment is not necessary. Release of the locking member allows the biasing member to adjust a resting position of brake pads independent of driver applied brake pressure.

Abstract: A parking brake having an electromechanical and hydraulic device for gripping a pack of movable sectors connected mechanically to the wheels to exert the desired braking force on the wheels. The parking brake is characterized by having an oil flow regulating valve assembly, in turn having a first control solenoid valve and a second safety solenoid valve in series with each other.

Abstract: An automatic parking brake system is provided in which a parking piston that enables a parking brake state to be obtained by forward movement in response to a parking control fluid pressure acting on a rear face of the parking piston is slidably fitted into a casing, and a lock mechanism is provided within the casing in back of the parking piston to automatically lock in response to forward movement of the parking piston in order to mechanically lock the parking piston at a forward position and unlock in response to a parking release control fluid pressure acting on the lock mechanism, the parking control fluid pressure and the parking release control fluid pressure being obtained by a fluid pressure control mechanism for controlling a fluid pressure generated by a fluid pressure source. This enables an automatic parking brake state to be obtained by a simple structure without consuming power.

Abstract: The present invention provides an electric parking brake system with one cable that has only one cable between an actuator, serving as a power generator, and parking cables and high flexibility in laying-out for mounting to a vehicle. According to an electric parking brake system with one cable of the invention, an actuator that converts torque of a motor into axial moving force to operate parking cables is manufactured into a single module, a housing that defines the whole external shape of the actuator is formed into an integral unit by injection molding, in which vibration caused by rotation in the operation of the actuator is absorbed by elastic members, so that a small-sized actuator having improved workability in mounting can be obtained and desired performance, such as reduction of operational noise caused by absorption of vibration, can be achieved.

Abstract: A cart having a frame for conveying cargo. The cart includes at least one brake assembly mounted within the frame of the cart. The brake assembly is configured to provide braking by engaging and disengaging a rear wheel axle. The cart further includes a control mechanism configured to selectively engage and disengage the brake assembly by rotation of a cart handle. In addition, the cart includes a brake release device configured to disengage the brake assembly when carts are nested.

Abstract: A disk brake kit including a pair of brake pads disposed on opposite sides of a brake disc and carried from calipers suspended from a kit frame indexed to predetermined land marks on the wheel housing.

Abstract: A parking brake system is provided in which a parking brake state of a wheel brake is obtained by forward movement of a parking piston slidably fitted into a casing with the rear side of the parking piston facing a parking control fluid pressure chamber, a lock piston forming part of a lock mechanism for mechanically locking the forwardly moved state of the parking piston is slidably fitted into the casing to the rear of the parking piston and urged forwardly by a spring, an opening provide in a portion of the casing that the rear side of the lock piston faces is closed by a detachable lid member, a tool connection part enables a tool inserted through the opening to be detachably connected to the tool connection part. This enables an automatic parking brake state to be obtained by a simple structure without consuming power, and the parking brake state to be released by a manual operation for maintenance or inspection.

Abstract: A cart braking device includes a swivel unit, a shaft unit and a braking unit which has a central shaft, an orientation member, a braking member and a base. The central shaft is coupled with the orientation member and has an elastic piece for moving the central shaft upward. A bottom of the orientation member has an orientation gear and a top of the braking member has a fixation gear corresponding to the orientation gear. The braking member is disposed in the base and includes two braking pads. An elastic member is disposed between the base and the braking member, and can move the braking member away from the base. When the braking pads are pressed against the wheel, the cart braking device stops the rotation of the wheel. When the orientation gear is engaged with the fixation gear, the cart braking device prevents the wheel from changing direction.

Abstract: The present invention is an anti theft device for bicycles or motorcycles, which comprise of a brake lever, mounted on the handlebar. The brake lever lock provides a strong friction on the wheel rim or brake-disk which makes the wheel un-rotational, because tensions of the brake cable always pull on the brake caliper in brake lever locks state and the brake will work normally in unlock state.

Abstract: A power strut assembly for a vehicle includes a first strut member having joined outer walls that define an interior cavity. The first strut member extends from a first end to a second end. The first end includes a base wall joined to the outer walls. A second strut member also having joined outer walls defining an inner cavity extends from a first end to a second end. The second strut member is telescopically disposed within the interior cavity of the first strut member. A lead screw extends from a first end to a second end and is rotatively retained at the first end of the first strut member. The lead screw extends into the interior cavities of the first and second strut members. A clutch is retained by the second strut member and the lead screw is positioned to interact with the clutch.

Abstract: A lock piston operates to automatically lock a parking brake piston which achieves a parking brake applied state in response to hydraulic pressure in a parking brake application control hydraulic chamber and operates to release a locked state in response to hydraulic pressure in a parking brake release control hydraulic chamber, and a manual change-over unit holding the hydraulic pressure in the parking brake release control hydraulic chamber to a hydraulic pressure on a lock release side, is provided among the wheel brake side hydraulic path, the parking brake application control hydraulic chamber and the parking brake release control hydraulic chamber by bypassing a hydraulic pressure control unit which changes over the application or release of hydraulic pressure to the parking brake application control hydraulic chamber and the parking brake release control hydraulic chamber.

Abstract: A parking brake system is provided in which a parking brake state is obtained by forward movement of a parking piston in response to the action of a parking control fluid pressure, and a forward operating state of the parking piston is mechanically locked by a lock mechanism. Moreover, an input member of a brake mechanism and the parking piston are connected by a coupling linkage. A lock piston of the lock mechanism moves toward one side in the axial direction when the parking piston moves forward, and a locking part provided at one end of the lock piston engages from the rear with a retaining part provided on a middle section of the coupling linkage while straddling the middle section of the coupling. This enables an automatic parking brake state to be obtained by a simple structure without consuming power.