Traction machine: It is the main driving machinery of the elevator, driving the elevator car and counterweight device to move up and down.
Traction machine consists of: motor, brake, reducer (box), traction sheave, etc.
Traction machine classification:
1. Geared traction machine: The power of the dragging device is transmitted to the traction machine on the traction wheel through the intermediate reducer, in which The reduction box usually adopts worm gear transmission (helical gear transmission is also used). The motors used in this kind of traction machine include AC and DC. They are generally used in low-speed elevators and high-speed elevators. The drag ratio is usually 35:2.
2. Gearless traction machine: The power of the dragging device is directly transmitted to the traction machine on the traction wheel without using an intermediate reducer. In the past, most of these traction machines were powered by DC motors. Now, domestic AC permanent magnet synchronous gearless traction machines with independent intellectual property rights have been developed in China, such as the Xuchang Boma traction machine. The traction ratio is 2:1
Motors are devices that convert electrical energy into mechanical energy and are distributed at various users. Motors are divided into DC motors and AC motors according to the power source used. Most motors are AC motors, which can be synchronous motors or asynchronous motors (the stator magnetic field speed of the motor does not maintain the same speed as the rotor rotation speed).
It is a machine that converts electrical energy into mechanical energy. Usually the power part of the motor performs rotational motion, and this kind of motor is called a rotor motor; some also perform linear motion, which is called a linear motor. Electric motors can provide a wide range of power, from milliwatts to tens of thousands of kilowatts. The motor is very convenient to use and control. It has the capabilities of self-starting, accelerating, braking, reversing, and holding, etc., and can meet various operating requirements; the motor has high working efficiency, no smoke, odor, environmental pollution, and noise. Also smaller. Due to its series of advantages, it is widely used in various aspects such as industrial and agricultural production, transportation, national defense, commercial and household appliances, and medical electrical equipment.
The most widely used among various motors is the AC asynchronous motor (also known as induction motor). It is easy to use, reliable in operation, low in price, and has a solid structure, but the power factor is low and speed regulation is difficult. Synchronous motors are commonly used for large-capacity and low-speed power machines (see synchronous motor). Not only does the synchronous motor have a high power factor, but its speed has nothing to do with the load and is only determined by the grid frequency. The job is relatively stable. DC motors are often used where a wide range of speed regulation is required. However, it has a commutator, has a complex structure, is expensive, is difficult to maintain, and is not suitable for harsh environments. After the 1970s, with the development of power electronics technology, the speed regulation technology of AC motors has gradually matured, the equipment prices have become increasingly lower, and it has begun to be applied. The maximum output mechanical power that the motor can bear under the specified working mode (continuous, short-time operation, intermittent periodic operation) without causing overheating of the motor is called its rated power. When using it, pay attention to the regulations on the nameplate. . When the motor is running, care must be taken to match the characteristics of the load with the characteristics of the motor to avoid overrunning or stalling. There are many ways to adjust the speed of electric motors, which can adapt to the speed changes of different production machinery. Generally, when the motor speed is adjusted, its output power will change with the rotation speed. From the perspective of energy consumption, speed regulation can be roughly divided into two types: ① Keep the input power unchanged. By changing the energy consumption of the speed regulating device, the output power is adjusted to adjust the speed of the motor. ②Control the motor input power to adjust the motor speed.