Drum brakes are one of the important parts in the vehicle braking system. Appearing since 1900, until now, thanks to the advantages of low production costs, easy maintenance, and good braking power, this type of brake is still commonly used on many different vehicle models.
What are drum brakes?
Brakes are a part of the car's safety system, which manufacturers are constantly investing in and developing. In a car there will be many different types of brakes to ensure safety when traveling, one of which is drum brakes. Brakes help the driver control the speed of travel and stop the vehicle promptly in necessary cases.

This braking system is mainly located on the rear axle of the wheel. They are designed in the form of a closed box, with a structure and operating principle that is not too complicated. nuoc lam mat o to mau xanh mau hong Compared to many popular types of brakes today, this type of brake produces good braking force and lower production costs. For that reason, this type of brake is widely used on all types of vehicles, especially commercial vehicles such as passenger cars, tourist cars and even motorbikes.

Drum brakes help control the vehicle's moving speed

Drum brakes help control the vehicle's moving speed (Source: Collected)

Structure of automobile drum brakes
This brake system is composed of main components, including: brake drum, brake cylinder, brake shoe, return spring, piston, cuppen. The roles of each department are as follows:

The brake drum is a hollow outer box, attached to the wheel axle and rotating with the wheel. This part creates a friction surface to slow or stop the wheel when the brake pads are pressed against it.
Brake cylinders create space to hold components such as pistons, cups, and oil. Cylinder operation is also quite important. If this part is faulty or damaged, it can affect the overall operation of the entire drum brake system.
Brake pistons work thanks to oil pressure. When there is oil pressure, the piston will be pushed out, the brake shoe will be pressed against the brake drum. That process helps the vehicle slow down or stop completely.
The brake shoe is placed directly on the surface of the brake drum. This is the part that creates friction with the brake drum.
The return spring is responsible for returning the piston to its original position when oil pressure decreases.
Cuppen helps keep the cylinder sealed, avoiding oil and air leakage.
In addition to the above parts, in drum brakes there are a number of other components that are responsible for supporting or transmitting force such as: pads, struts, cables,...

Principle of drum brake operation
The way this type of brake works is also quite simple. Essentially, drum brakes create force that causes the wheel to slow or stop turning.

Specifically, when the user presses on the brake, the impact force will be amplified by the brake booster. The cylinder unit will convert this force into hydraulic pressure (also known as oil pressure). Oil pressure acts on the piston and helps this part create pressure on the brake shoes. The brake shoe will create surface friction with the inside of the brake drum. Because the brake drum rotates with the wheel, it will slow down and stop the wheel.

Advantages and disadvantages of car drum brakes
Drum brakes are a part that ensures vehicle safety. So what are the advantages and disadvantages of this braking system?

Advantages of drum brakes
Compared to disc brakes of equivalent diameter, drum brakes create more braking force. nuoc lam mat dong co In addition, the brakes do not cause dangerous slipping or dragging for the vehicle driver, a phenomenon commonly encountered with disc brakes when braking suddenly.
The monolithic box design helps protect the internal components from environmental impacts such as mud, water, dust, etc.
The thickness of the brake shoe is thicker than the thickness of the disc brake pad, so users will have less maintenance costs.
Production costs are low and reproducible.
Disadvantages of drum brakes
Due to the closed box design, the heat dissipation mechanism is poor, the brake temperature increases rapidly, which can affect the operation of the components inside the drum.
Due to the slow deceleration time, in case the user brakes suddenly or goes downhill, this type of brake works worse than disc brakes.
Brake weight is heavier than disc brakes, which can affect vehicle load.

Types of drum brakes
Brakes are classified based on their purpose and the characteristics that the leading and trailing shoes create. Below are four commonly used types of drum brakes.

Brakes with two guide shoes
This type of brake will have two guide shoes and two wheel cylinders. With such a structure, the brake creates strong and outstanding braking force. Therefore, two-lead brake pads are often equipped on small to medium sized trucks.

Drive and drag drum brake type
This type of brake has a fixed cylinder and anchor design, creating stable braking force even when the vehicle is moving forward or backward. nuoc lau kinh o to cua nhat Guide and traction brakes are often used on passenger cars.

Single servo brake type
The structure of this type of brake includes a servo, adjusting cylinder and fixed wheel cylinder.

Two-servo brake type
This type of brake has the same structure as a servo brake but includes two servo brakes. Dual servo brakes create very large braking force, so they are often used as central truck brakes, forklift brakes, and handbrakes for passenger cars.

Compare drum brakes and disc brakes, which type is better?
Besides drum brakes, disc brakes are also one of the commonly used types of brakes on cars. So between these two types of brakes, which one is better? Let's find out through the following comparison table of two types of brakes.