Electric motor with gearbox: features, device and principle of operation

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

An electric motor with a gearbox, or, as it is also called, a geared motor, can be described as a separate unit. The joint work of the electric motor and the gearbox led to the fact that this device began to be used in a large number of different areas.

General information

From the main advantages of the electric motor with a gearbox, several of the following can be distinguished:

• This machine is quite compact yet does a huge amount of work.
• The light physical weight of this device also increases its portability.
• The electric motor has a fairly high efficiency.
• Installation and maintenance of this electromechanical assembly is quite simple.

The general principle of operation of the motor-reducer electric motor is that its first part converts any energy into mechanical energy, and the second element is already intended to transfer the available mechanical energy to the output shaft to change its speed.

Types of electric motors

Currently, there are several types of gear motors that are considered the most common:

• worm gears;
• cylindrical type;
• conical type;
• planetary gearboxes;
• wave and combined type.

It is logical that the belonging of an electric motor with a gearbox to one of the above types will depend on the type of gearbox itself. It is also important to note that it is this element that will affect exactly how the output shaft speed will change, as well as the method of transferring mechanical energy to the working body of the device.

Assume that the principle of operation of the worm-type gearbox assumes that the dimensions of the part will be quite small, and the operation of the engine is characterized by the absence of noise. To date, this type of gearbox can be considered the second most common.

What is a reducer

During the operation of the electric motor, mechanical energy is created, which must be transferred to the working body of a machine. It is for this purpose that the reducer is used. Another very important point. When operating a 220v electric motor with a gearbox, it turns out that the torque of the input shaft is very high. After some type of energy is converted into mechanical energy and then transferred to the output shaft, the gearbox lowers the number of revolutions, but maintains a fairly hightorque.

The application of this feature in practice can be clearly seen during the operation of manual machines. In such types of devices, a planetary, chain or gear type of transmission is often used. However, today there are units in which the electric motor with the gearbox is configured to issue a non-rotary movement. A striking example of a secondary type of work of this device can be jackhammers (hammers).

Part properties

An electric motor with a gearbox at 220V has its own characteristics. It’s worth starting with what concerns almost everyone in the first place - this is the service life and reliability of the equipment. These two properties will directly depend on what parts this element is made of. If we talk about household units, then the gears can be made of plastic. Professional gearboxes are always made entirely of metallic materials.

A positive factor is also the fact that the gearbox housing is made of metal, other materials are considered unsuitable. The advantage of a metal case specifically for the gearbox will be that in this case it will be much easier to endure all loads and possible shocks.

Another important property of a gear motor is that the presence of such a part allows you to change the speed of the output shaft in a stepwise manner.

Motor control principle

ForIn order to supply power to the electrical parts of the motor, various circuits are used, including microprocessor-based electric drives. Another indispensable element in any system that uses an electric motor with a gearbox has become a rectifier. It is used as a converter, the task of which is to convert the alternating current flowing through the network into the direct current required for the operation of the unit. It is worth noting that there are cordless tools that receive their power from this element. In this case, the use of a rectifier is not required.

The system also has an output shaft speed controller. The simplest version of the converter of these frequencies is several connected control relays, the number of revolutions on which is set manually by a person. In addition, some models can be equipped with a magnetic starter, pressing which will change the direction of rotation of the output shaft. The principle of operation of such engines is the most common, and the function itself is called reverse.

Slow-speed gear motor

The use of such models, which are also called low-speed, is common where it is necessary to maintain a small number of revolutions. A striking example of the use of such devices was the electric drives of hoisting and transport machines. Most often, the mining and metallurgical industry becomes the scope of application, but this model is quite suitable for general industrial applications.

Electric motor coupling withreducer

The purpose of this part is to transmit torque between shafts, or to transmit torque between a shaft and parts that can be mounted on it.

This element is also a connecting element and performs such functions as connecting the motor shaft and the drive shaft of the gearbox, as well as the driven shaft of the gearbox with the driven device. In addition, there are specialized units in which the clutch can also be used in order to connect and shift gears directly in the element itself. In addition, this small part can be used to reduce the dynamic loads that affect the gearbox, as well as limit the transmitted torque.

There are several varieties of couplings. One of the types is called a blind coupling. It is used when it is necessary to connect the shaft axes that coincide, and during operation any shaft displacements are completely excluded.

Comparison of two types

Today, the most common electric motors are those whose gearbox type is worm or cylindrical. These two main types can be compared with each other using their main characteristics. The advantages of the cylindrical type over the worm type will be given.

The efficiency of this type of gearbox reaches 98% if the gear ratio is not taken into account. This indicator provides excellent energy savings. One of the most important advantages ishigh load capacity. In other words, a cylindrical type of gearbox is capable of transmitting much more force than a worm gear, provided that both of these elements have the same dimensions. In addition, this type of unit has a fairly high kinematic accuracy.