An electrically actuated parking brake has a single electric motor producing a torque, a first torque limiting device with a first spring force, and a second torque limiting device with a second spring force. The first torque limiting device fully transmits a first portion of the torque to a first spindle until a first clamp force overcomes the first spring force and the second torque limiting device fully transmits a second portion of the torque to a second spindle until a second clamp force overcomes the second spring force. When the first clamp force overcomes the first spring force and the second spring force overcomes the second clamp force, the first portion of the torque that exceeds the first spring force is transmitted to the second spindle by the second torque limiting device.

A disc brake including a piston driving mechanism. The piston driving mechanism includes an input member extended in a cylinder in a protruding direction of a piston, including a threaded portion formed on a circumferential surface of the input member, and configured to be rotated with transmission of torque from an electric motor; a tubular rotation linear motion member including an engaging threaded portion that is engaged with the threaded portion of the input member, and configured to move in an axial direction of the cylinder by rotation of the input member to transmit a torque of the electric motor to the piston; a tubular support member supported on a caliper main body to be not rotatable and placed on an outer side in a radial direction with respect to the rotation linear motion member; and a rolling element placed between the support member and the rotation linear motion member.

A disc brake including a piston driving mechanism. The piston driving mechanism includes an input member extended in a cylinder in a protruding direction of a piston, including a threaded portion formed on a circumferential surface of the input member, and configured to be rotated with transmission of torque from an electric motor; a tubular rotation linear motion member including an engaging threaded portion that is engaged with the threaded portion of the input member, and configured to move in an axial direction of the cylinder by rotation of the input member to transmit a torque of the electric motor to the piston; a tubular support member supported on a caliper main body to be not rotatable and placed on an outer side in a radial direction with respect to the rotation linear motion member; and a rolling element placed between the support member and the rotation linear motion member.

A slack adjuster for use with a railway braking system which has an increased let-out length that enables the use of brake shoes having an increased thickness. The slack adjuster includes at least one of a dual spring and canister assembly, an external yoke trigger, or a combination of both a dual spring and canister assembly and an external yoke trigger. A method of retrofitting a truck mounted brake system is provided, in which the slack adjuster is positioned within the brake system in order to increase the let-out length while maintaining a predetermined spatial envelope within the brake system. The slack adjuster has an increased let-out length enabling the use of thicker brake shoes without requiring modification of the interacting components of the truck mounted brake system since the overall size of the slack adjuster remains the same.

A slack adjuster for use with a railway braking system which has an increased let-out length that enables the use of brake shoes having an increased thickness. The slack adjuster includes at least one of a dual spring and canister assembly, an external yoke trigger, or a combination of both a dual spring and canister assembly and an external yoke trigger. A method of retrofitting a truck mounted brake system is provided, in which the slack adjuster is positioned within the brake system in order to increase the let-out length while maintaining a predetermined spatial envelope within the brake system. The slack adjuster has an increased let-out length enabling the use of thicker brake shoes without requiring modification of the interacting components of the truck mounted brake system since the overall size of the slack adjuster remains the same.

A caliper body (12) of a disc brake apparatus (10) includes an accommodating portion (14a) which accommodates a piston (20) for pressing a brake pad (66), a cam lever (42) for generating a pressing force through rotation, and a pressing force transmission mechanism (24) which is interposed between the piston (20) and the cam lever (42) to transmit a pressing force to the piston (20). The accommodating portion (14a) has an opening portion through which the piston (20), the cam lever (42) and the pressing force transmission mechanism (24) can be assembled into the caliper body (12) from a thick back side thereof, and both the accommodating portion (14a) and the opening portion are opened to a rotor disposition side area in the caliper body (12).

A method for operating a parking brake which has an actuator with an actuating element and an electric motor, the electric motor is operatively connected to the actuating element in order to displace the latter, the electric motor is actuated in order to displace the actuating element by a predefined movement travel, and an actual movement travel of the actuating element is monitored in order to actuate the electric motor. The method includes determining the actual movement travel of the actuating element in a manner which is dependent on a motor current and/or a motor voltage of the electric motor.

A method for operating a parking brake which has an actuator with an actuating element and an electric motor, the electric motor is operatively connected to the actuating element in order to displace the latter, the electric motor is actuated in order to displace the actuating element by a predefined movement travel, and an actual movement travel of the actuating element is monitored in order to actuate the electric motor. The method includes determining the actual movement travel of the actuating element in a manner which is dependent on a motor current and/or a motor voltage of the electric motor.

A disc brake including a brake actuation mechanism and an adjustment mechanism, which is configured to provide, in addition to a reduction of the clearance between a brake pad and a brake disc during brake application, a further increase of the clearance during brake release motion with a value, which may be smaller, equal or larger than the previous clearance reduction. The brake actuation mechanism for that purpose could provide a different regulator unit. Moreover, the invention suggests a method for adjusting the clearance between a brake pad and a brake disc providing a clearance increase during brake release motion, accordingly.

A disc brake including a brake actuation mechanism and an adjustment mechanism, which is configured to provide, in addition to a reduction of the clearance between a brake pad and a brake disc during brake application, a further increase of the clearance during brake release motion with a value, which may be smaller, equal or larger than the previous clearance reduction. The brake actuation mechanism for that purpose could provide a different regulator unit. Moreover, the invention suggests a method for adjusting the clearance between a brake pad and a brake disc providing a clearance increase during brake release motion, accordingly.