How many kinds of brakes are there?
The brake can be divided into mechanical brake, pneumatic brake, hydraulic brake, electric brake and manual brake according to the driving components (categories). The common brake is divided into friction type and non friction type.
The brake can be divided into mechanical brake, pneumatic brake, hydraulic brake, electric brake and manual brake according to the driving components (categories). The common brake is divided into friction type and non friction type. The friction type brake is divided into external holding block brake, internal expanding shoe brake, belt brake and disc brake; Non friction brake is divided into magnetic powder brake, magnetic eddy current brake and water eddy current brake.
(1) The belt brake has simple structure, large wrap angle, large braking torque, large bending force on the brake wheel axle, and uneven specific pressure and wear of the brake belt. The braking torque of simple and differential belt brakes is related to the rotation direction, which limits the application range. Poor heat dissipation, suitable for braking of large machines and compact requirements, such as machine tools, mobile cranes, hoists, etc.
(2) The block brake has simple and reliable structure, general heat dissipation, sufficient and uniform backing of pads, and easy adjustment. For the straight brake arm structure, the brake torque has nothing to do with the steering of the brake shaft. The brake shaft is not subject to bending stress, but the wrap angle and brake torque are small. The manufacturing is more complex than the belt brake, the lever system is complex, and the overall dimension is large. Block brake is the most widely used, mainly used for machinery with frequent work and large installation space, such as hoisting and transportation, metallurgical machinery.
(3) The internal expansion shoe brake is composed of two built-in brake shoes that extrude the brake drum radially outward to generate braking torque. Compact structure, good heat dissipation and easy sealing. Most of them are normally open, and they are often used in situations where the installation space is limited. They are widely used in the braking of wheeled cranes and various vehicles (such as automobiles, tractors, etc.).
(4) The disc brake uses axial pressure to compress the disc or conical friction surface to achieve braking. When the whole disc type or point disc type is symmetrically arranged, the brake shaft is not subject to bending force. Compact structure, uniform wear of pads, and the brake torque is independent of the rotation direction. When used for dust and moisture prevention, it can be made into a sealed type. Point disc type has good heat dissipation, while full disc type has poor heat dissipation. It is especially suitable for occasions with high compactness requirements, such as electric hoists on wheels of vehicles.
(5) The magnetic particle brake uses the internal force generated during magnetic particle magnetization. Small size, light weight, small excitation power, and braking torque is independent of the rotational speed of the rotating parts. Magnetic particles will cause wear of parts. It is mainly used for braking (adjustable braking torque), precise positioning, test loading, tension control, etc.
(6) The magnetic eddy current brake is durable, easy to maintain, and has a wide adjustment range. However, the efficiency is low at low speed and the temperature rises, so heat dissipation measures must be taken. It is often used in machinery with vertical load (such as the lifting mechanism of hoisting machinery) to absorb the function before parking to reduce the load of parking brake.