Provided is motor-driven drum brake system including: a motor-driven drum brake including a brake shoe inside a drum and allowing the brake shoe to be pressed on an inner surface of the drum by hydraulic pressure of a wheel cylinder or an operation of a motor to perform braking; and a controller configured to control the motor to engage the motor-driven drum brake, wherein the controller is configured to, upon a total count of parking apply operations of the motor-driven drum brake being greater than a preset count when performing a parking apply operation, correct a target clamping force of the motor-driven drum brake and perform the parking apply operation according to the corrected target clamping force.

Brake systems, vehicles having such brake systems, and methods of operating and installing the brake systems on vehicles. Such a brake system operates one or more brakes to reduce the speed of the vehicle through the operation of a brake pedal. The system includes a hydraulic circuit functionally coupled to the one or more brakes and configured to apply a braking force with the brake(s) that is in relation to a change in pressure of hydraulic fluid within the hydraulic circuit, and an air circuit functionally coupling the brake pedal to the hydraulic circuit. The air circuit is configured to convert manual actuation of the brake pedal to a change in the pressure of the hydraulic fluid within the hydraulic circuit and thereby apply a braking force in relation to a degree of actuation of the brake pedal.

An S-cam brake including a brake chamber to which compressed air is supplied; a slack adjuster rotatably connecting to the brake chamber; an S-cam unit having an S-cam connecting to and rotating around the slack adjuster; and a drum having a lining generating braking force with widening according to rotation of the S-cam is provided, wherein the brake chamber includes an upper housing having an air supply port through which compressed air is introduced; a lower housing coupled to the upper housing to form an internal space; a diaphragm having edges fixed to the upper housing and the lower housing and deformed by compressed air; a piston disposed to contact the diaphragm and move linearly; a piston push rod extending from the piston and having one end connected to the slack adjuster; and a spring having one end supported by the piston and the other end supported by the lower housing, wherein a thickness of the upper housing is greater than a thickness of the lower housing.

An S-cam brake including a brake chamber to which compressed air is supplied; a slack adjuster rotatably connecting to the brake chamber; an S-cam unit having an S-cam connecting to and rotating around the slack adjuster; and a drum having a lining generating braking force with widening according to rotation of the S-cam is provided, wherein the brake chamber includes an upper housing having an air supply port through which compressed air is introduced; a lower housing coupled to the upper housing to form an internal space; a diaphragm having edges fixed to the upper housing and the lower housing and deformed by compressed air; a piston disposed to contact the diaphragm and move linearly; a piston push rod extending from the piston and having one end connected to the slack adjuster; and a spring having one end supported by the piston and the other end supported by the lower housing, wherein a thickness of the upper housing is greater than a thickness of the lower housing.

Disclosed herein an electric parking brake. The electric parking brake according to an embodiment of the disclosure includes a power transmission unit that receives a rotational force from an actuator that generates a driving force for implementing a parking braking force and converts the rotational force into a linear motion to press or release a pair of brake shoes disposed on both sides of an inside of a drum, respectively, wherein the power transmission unit includes a pressing piston configured to press the pair of brake shoes, a driving cylinder configured to guide the pressing piston, and a dust cover installed between the pressing piston and the driving cylinder, the dust cove formed to be deformable according to an operation of the pressing piston, wherein the dust cover is configured to maintain internal airtightness of the power transmission unit and prevent foreign substances from entering.

An electronic parking brake device including: a plate part having a brake shoe rotatably mounted thereon; a housing part mounted on the plate part and configured to guide hydraulic pressure; a motor part mounted on the housing part, and driven when power is applied thereto; a piston part mounted on the housing part, and moved by hydraulic pressure so as to operate the brake shoe; and an operation part embedded in the housing part, disposed between the piston parts, and driven by the motor part so as to push the piston parts.

An electronic parking brake device including: a plate part having a brake shoe rotatably mounted thereon; a housing part mounted on the plate part and configured to guide hydraulic pressure; a motor part mounted on the housing part, and driven when power is applied thereto; a piston part mounted on the housing part, and moved by hydraulic pressure so as to operate the brake shoe; and an operation part embedded in the housing part, disposed between the piston parts, and driven by the motor part so as to push the piston parts.

An electronic parking brake device may include: a plate part having a brake shoe rotatably mounted thereon; a housing part mounted on the plate part and configured to guide hydraulic pressure; a motor part mounted on the housing part, and driven when power is applied thereto; a piston part mounted on the housing part, and moved by hydraulic pressure so as to operate the brake shoe; and an operating part embedded in the housing part, and driven by the motor part so as to move the piston part.

An electronic parking brake device may include: a plate part having a brake shoe rotatably mounted thereon; a housing part mounted on the plate part and configured to guide hydraulic pressure; a motor part mounted on the housing part, and driven when power is applied thereto; a piston part mounted on the housing part, and moved by hydraulic pressure so as to operate the brake shoe; and an operating part embedded in the housing part, and driven by the motor part so as to move the piston part.

A drum brake assembly that includes a brake drum, first and second brake shoes, a cam shaft, a first tappet, a second tappet, and a wear adjuster mechanism. The wear adjuster mechanism has a cross shaft and a sensor. The sensor is configured to detect rotation of the cross shaft about a longitudinal axis to monitor wear of the first and second brake shoes and a braking surface of the brake drum.